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Find video protocols related to scientific articles indexed in Pubmed.
Endovascular embolization for managing anastomotic bleeding after stapled digestive tract anastomosis.
Acta Radiol
PUBLISHED: 11-20-2014
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Anastomotic bleeding is an infrequent but life-threatening complication after stapled digestive tract anastomosis. Endovascular embolization is one of the available treatments, but precise clinical outcomes are yet to be evaluated.
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Fistula Output Microorganism-Susceptible Antimicrobial Prophylaxis Is Associated with a Lower Risk of Surgical Site Infection in Gastrointestinal Fistula Patients Undergoing One-Stage Definitive Surgery.
Surg Infect (Larchmt)
PUBLISHED: 11-18-2014
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Abstract Background: Empiric broad-spectrum antimicrobial prophylaxis (AMP) may not be sufficient to minimize the risk of surgical site infections (SSIs) after definitive surgical treatment of gastrointestinal (GI) fistula. This study investigates whether AMP targeted toward fistula microbiology is associated with a lower risk of SSIs in GI fistula patients undergoing one-stage definitive surgery. Methods: Fistula output was sampled from the abdominal fistula opening for microbial growth and drug sensitivity prior to surgery. The primary outcome measure was the overall incidence rate of SSIs. Results: A total of 191 patients were examined. Pre-operative microbial culture identified microbial growth in 149 patients (76.0%). Post-operative SSIs occurred in 51 patients (26.7%). Risk index category, abdominal incision length, and time of peritoneal drain removal had significantly negative impacts on SSIs frequency. Sensitive AMP agents were associated with a significantly lower risk of SSIs, compared with insensitive AMP agents, but with a similar risk to indefinite AMP agents (23.2% vs. 45.2% vs. 23.1%; odds ratio [95% confidence interval]: 2.724 [1.063, 6.979], p=0.034; 1.008 [0.467-2.177], p=0.984). Conclusions: Antimicrobial prophylaxis targeted toward fistula output AMP may minimize the occurrence of SSIs after one-stage definitive surgical treatment of GI fistula.
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MiCroKiTS 4.0: a database of midbody, centrosome, kinetochore, telomere and spindle.
Nucleic Acids Res.
PUBLISHED: 11-14-2014
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We reported an updated database of MiCroKiTS 4.0 (http://microkit.biocuckoo.org) for proteins temporally and spatially localized in distinct subcellular positions including midbody, centrosome, kinetochore, telomere and mitotic spindle during cell division/mitosis. The database was updated from our previously developed database of MiCroKit 3.0, which contained 1489 proteins mostly forming super-complexes at midbody, centrosome and kinetochore from seven eukaryotes. Since the telomere and spindle apparatus are critical for cell division, the proteins localized at the two positions were also integrated. From the scientific literature, we curated 1872 experimentally identified proteins which at least locate in one of the five positions from eight species. Then the ortholog detection was performed to identify potential MiCroKiTS proteins from 144 eukaryotic organisms, which contains 66, 45 and 33 species of animals, fungi and plants, respectively. In total, 87 983 unique proteins with corresponding localization information were integrated into the database. The primary references of experimentally identified localizations were provided and the fluorescence microscope figures for the localizations of human proteins were shown. The orthologous relations between predicted and experimental localizations were also present. Taken together, we anticipate the database can serve as a useful resource for further analyzing the molecular mechanisms during cell division.
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Self-assembled two-dimensional thermoresponsive microgel arrays for cell growth/detachment control.
Biomacromolecules
PUBLISHED: 10-31-2014
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Monodisperse poly(N-isopropylacrylamide-styrene) (PNIPAAmSt) microgels with different St/NIPAAm ratios have been synthesized via a one-step surfactant-free emulsion polymerization process. The resulting microgel dispersions were used to fabricate 2D arrays on the surface of silicon wafers/glass coverslips through dip coating. The thermal responsiveness of the PNIPAAmSt microgel arrays was examined by spectroscopic ellipsometry and the results unraveled that the thermoresponsive behavior of the arrays was highly consistent with the microgels dispersed in the bulk, showing high dependence on the content of styrene. The structure of the films varied from nonclose-packed 2D arrays to close-packed 2D arrays, depending on both properties of the microgels and array fabrication conditions. When the weight ratio of styrene was below 40%, the microgel arrays demonstrated effective control for cell growth and detachment across their volume phase transition temperatures (around 28 °C). The extent of swelling of the microgels was the key factor to determine whether the cells could detach from the film easily. For the rather close-packed 2D arrays prepared by the same kind of PNIPAAmSt microgels, the gaps between microgel particles showed no obvious effect on the rate of cell detachment.
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A flexible zwitterion ligand based lanthanide metal-organic framework for luminescence sensing of metal ions and small molecules.
Dalton Trans
PUBLISHED: 10-11-2014
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A new lanthanide metal-organic framework was constructed using a tripodal flexible zwitterion ligand (H3LBr3) which takes a chair-shaped configuration. The luminescence of the compound displays highly selective sensing of the Fe(3+) ion and nitrobenzene.
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Down-regulation of connexin43 and connexin32 in keratocystic odontogenic tumours: potential association with clinical features.
Histopathology
PUBLISHED: 10-02-2014
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The objective of this study was to explore the potential involvement of connexin43 (Cx43) and connexin32 (Cx32), two vital members of the connexin families, in the pathogenesis of keratocystic odontogenic tumours (KCOT).
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[Protective effect of formula of removing both phlegm and blood stasis on myocardial tissues of Chinese mini-swine with coronary heart disease of phlegm-stasis cementation syndrome].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 09-11-2014
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To study the protective effect of formula of removing both phlegm and blood stasis (TYTZ) on myocardial tissues of Chinese mini-swine with coronary heart disease of phlegm-stasis cementation syndrome.
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Effects of treatment with hydrogen sulfide on methionine-choline deficient diet-induced non-alcoholic steatohepatitis in rats.
J. Gastroenterol. Hepatol.
PUBLISHED: 09-11-2014
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Oxidative stress and inflammation play important roles in the progression from simple fatty liver to non-alcoholic steatohepatitis (NASH). The aim of this work was to investigate whether treatment with hydrogen sulfide (H2 S) prevented NASH in rats through abating oxidative stress and suppressing inflammation.
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The structure and activation of substrate water molecules in Sr(2+)-substituted photosystem II.
Phys Chem Chem Phys
PUBLISHED: 08-28-2014
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The mechanism of solar water oxidation by photosystem II (PSII) is of fundamental interest and it is the object of extensive studies both in the past and present. The solar water oxidation reaction of PSII occurs in the oxygen-evolving complex (OEC). The OEC consists of a tetranuclear manganese calcium-oxo (Mn4Ca-oxo) cluster that is surrounded by amino acid residues and inorganic cofactors. The role of the Ca(2+) ion in the water oxidation reaction is one of the most interesting questions that is yet to be answered. In this study, we probe the structural and functional differences induced by metal ion substitution in the Mn4Ca-oxo cluster by substituting the Ca(2+) ion in the OEC by a Sr(2+) ion. We apply two-dimensional (2D) hyperfine sublevel correlation (HYSCORE) spectroscopy to detect weak magnetic interactions between the paramagnetic Mn4Sr-oxo cluster and the surrounding protons in the S2 state of the OEC of Sr(2+)-substituted PSII. We identify three groups of protons that are magnetically interacting with the Mn4Sr-oxo cluster. Using the recently reported 1.9 Å resolution X-ray structure of the OEC in the S1 state [Umena et al.] and the high-resolution 2D HYSCORE spectroscopy studies of the S2 state of the OEC of Ca(2+)-containing PSII [Milikisiyants et al., Energy Environ. Sci., 2012, 5, 7747], we discuss the assignments of the three groups of protons that are magnetically coupled to the Mn4Sr-oxo cluster. Since hyperfine interactions are highly sensitive to small perturbations in the electronic and geometric structure of paramagnetic centers, a comparison of the 2D HYSCORE spectra of Sr(2+)-substituted and Ca(2+)-containing PSII allows us to draw important conclusions with respect to the structure of the substrate water molecules in the OEC and the role of the Ca(2+) ion in the water oxidation reaction. In addition, for the first time, we determine the experimental value of the spin projection factor for the Mn(III) ion of the Mn4Ca-oxo cluster as ?1 = ±1.7 from the assignment of the hyperfine interaction of the paramagnetic cluster with the protons of the D1-His332 residue of PSII.
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The Adaptor Protein p62 Is Involved in RANKL-induced Autophagy and Osteoclastogenesis.
J. Histochem. Cytochem.
PUBLISHED: 08-27-2014
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Previous studies have implicated autophagy in osteoclast differentiation. The aim of this study was to investigate the potential role of p62, a characterized adaptor protein for autophagy, in RANKL-induced osteoclastogenesis. Real-time quantitative PCR and western blot analyses were used to evaluate the expression levels of autophagy-related markers during RANKL-induced osteoclastogenesis in mouse macrophage-like RAW264.7 cells. Meanwhile, the potential relationship between p62/LC3 localization and F-actin ring formation was tested using double-labeling immunofluorescence. Then, the expression of p62 in RAW264.7 cells was knocked down using small-interfering RNA (siRNA), followed by detecting its influence on RANKL-induced autophagy activation, osteoclast differentiation, and F-actin ring formation. The data showed that several key autophagy-related markers including p62 were significantly altered during RANKL-induced osteoclast differentiation. In addition, the expression and localization of p62 showed negative correlation with LC3 accumulation and F-actin ring formation, as demonstrated by western blot and immunofluorescence analyses, respectively. Importantly, the knockdown of p62 obviously attenuated RANKL-induced expression of autophagy- and osteoclastogenesis-related genes, formation of TRAP-positive multinuclear cells, accumulation of LC3, as well as formation of F-actin ring. Our study indicates that p62 may play essential roles in RANKL-induced autophagy and osteoclastogenesis, which may help to develop a novel therapeutic strategy against osteoclastogenesis-related diseases.
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[Clinical analysis of syndrome-relative biological indices in acute lacuna encephalon infarction patients of upper hyperactivity of Gan Yang syndrome].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 08-21-2014
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To analyze and summarize changes of syndrome-related biological indices in acute lacuna encephalon infarction patients of upper hyperactivity of Gan yang syndrome (UHGYS), thus providing objective evidence for syndrome typing and disease identification.
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Evaluation of asymmetric polydimethylsiloxane-polyvinylidene fluoride composite membrane and incorporated with acetone-butanol-ethanol fermentation for butanol recovery.
J. Biotechnol.
PUBLISHED: 08-18-2014
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The polydimethylsiloxane-polyvinylidene fluoride (PDMS-PVDF) composite membrane was studied for its pervaporation performance to removal of butanol from butanol/ABE solution, fermentation broth as well as incorporated with acetone-butanol-ethanol (ABE) fermentation. The total flux and butanol titer in permeate through the PDMS-PVDF membrane were up to 769.6g/m(2)h and 323.5g/L at 80°C, respectively. The butanol flux and total flux increased with increasing the feed temperature as well as the feed butanol titer. The butanol separation factor and butanol titer in permeate decreased slightly in the presence of acetone and ethanol in the feed due to their preferential dissolution and competitive permeation through the membrane. In fed-batch fermentation incorporated with pervaporation, butanol titer and flux in permeate maintained at a steady level with the range of 139.9-154.0g/L and 13.3-16.3g/m(2)h, respectively, which was attributed to the stable butanol titer in fermentation broth as well as the excellent hydrophobic nature of the PDMS-PVDF matrix. Therefore, the PDMS-PVDF composite membrane had a great potential in the in situ product recovery with ABE fermentation, enabling the economic production of biobutanol.
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Extraction of heavy metals from contaminated soil by Cinnamomum camphora.
Ecotoxicology
PUBLISHED: 08-09-2014
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83 acres of rice paddy fields in Taoyuan county, Taiwan, were polluted by cadmium (Cd), chromium (Cr) and copper (Cu) through a nearby irrigation channel, and rice plantation was ceased in 1987. Camphor trees (Cinnamomum camphora) have been planted in 2 acre of the above fields since 1991. Heavy metal accumulation of roots, leaves, branches and heartwood of camphor trees were analyzed during 20-year afforestation. Averaged Cd contents of the roots were found larger than the ones of the branches, leaves, sapwood and heartwood of camphor trees growing in three polluted plots. Averaged diameters at breast height (DBH) of the planted camphor trees were 13-15 cm. Cd pollution did not significantly impact the growth of camphor trees, as similar DBH's were found from both polluted and control sites. Annual growths of DBH were from 0.63 to 0.77 cm year(-1). Planting camphor trees sequestered 68.8 ton biomass per acre. During 20-year period, 0.69-1.98 ton C year(-1) ha(-1) were sequestered on three polluted plots. The above numbers exceeded IPCC LULUCF reference values 0.31-0.53 ton C year(-1) ha(-1) for activities at forest lands.
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ALDOB acts as a novel HBsAg-binding protein and its coexistence inhibits cisplatin-induced HepG2 cell apoptosis.
Crit. Rev. Eukaryot. Gene Expr.
PUBLISHED: 07-30-2014
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Chronic infection with hepatitis B virus is a cause of end-stage liver disease and hepatocellular carcinoma (HCC). We previously screened fructose-bisphosphate aldolase B (ALDOB) as a candidate binding protein of hepatitis B surface antigen (HBsAg) using a yeast 2-hybrid assay. In this study we aimed to confirm ALDOB as a binding protein of the S region of the HbsAg (HBs) and to investigate the function and involved mechanism between its interactions during HCC development. Our results demonstrated that both of exogenous and endogenous ALDOB proteins bind to HBs and colocalize in the cytoplasm in vitro. The coexistence of HBs and ALDOB inhibit apoptosis of cisplatin-induced HepG2 cells. Furthermore, western blot analysis showed the coexistence of HBs and ALDOB enhance the phosphorylations of AKT and its downstream of GSK-3? (phosphorylation); decreased expression of the pro-apoptotic proteins Bax, Bid, Bim, and Puma; and increased expression of the prosurvival proteins Bcl-2, Bcl-xl, and Mcl-1 in HepG2 cells. These findings suggest that interaction between HBs and ALDOB might be applied as a potential therapeutic target during the treatment of HBV-related hepatitis or HCC.
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[Effect of formula of removing both phlegm and blood stasis in improving cardiac function of Chinese mini-swine with coronary heart disease of phlegm-stasis cementation syndrome].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 06-21-2014
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To evaluate that the effect of formula of removing both phlegm and blood stasis in improving cardiac function of Chinese mini-swine with coronary heart disease of phlegm-stasis cementation syndrome.
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Hydrogen-rich saline inhibits NLRP3 inflammasome activation and attenuates experimental acute pancreatitis in mice.
Mediators Inflamm.
PUBLISHED: 06-06-2014
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Increasing evidence has demonstrated that reactive oxygen species (ROS) induces oxidative stress and plays a crucial role in the pathogenesis of acute pancreatitis (AP). Hydrogen-rich saline (HRS), a well-known ROS scavenger, has been shown to possess therapeutic benefit on AP in many animal experiments. Recent findings have indicated that the NOD-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome, an intracellular multiprotein complex required for the maturation of interleukin- (IL-) 1?, may probably be a potential target of HRS in the treatment of AP. Therefore, in this study, we evaluated the activation of NLRP3 inflammasome and meanwhile assessed the degree of oxidative stress and inflammatory cascades, as well as the histological alterations in mice suffering from cerulein-induced AP after the treatment of HRS. The results showed that the activation of NLRP3 inflammasome in AP mice was substantially inhibited following the administration of HRS, which was paralleled with the decreased NF-?B activity and cytokines production, attenuated oxidative stress and the amelioration of pancreatic tissue damage. In conclusion, our study has, for the first time, revealed that inhibition of the activation of NLRP3 inflammasome probably contributed to the therapeutic potential of HRS in AP.
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GPS-SUMO: a tool for the prediction of sumoylation sites and SUMO-interaction motifs.
Nucleic Acids Res.
PUBLISHED: 05-31-2014
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Small ubiquitin-like modifiers (SUMOs) regulate a variety of cellular processes through two distinct mechanisms, including covalent sumoylation and non-covalent SUMO interaction. The complexity of SUMO regulations has greatly hampered the large-scale identification of SUMO substrates or interaction partners on a proteome-wide level. In this work, we developed a new tool called GPS-SUMO for the prediction of both sumoylation sites and SUMO-interaction motifs (SIMs) in proteins. To obtain an accurate performance, a new generation group-based prediction system (GPS) algorithm integrated with Particle Swarm Optimization approach was applied. By critical evaluation and comparison, GPS-SUMO was demonstrated to be substantially superior against other existing tools and methods. With the help of GPS-SUMO, it is now possible to further investigate the relationship between sumoylation and SUMO interaction processes. A web service of GPS-SUMO was implemented in PHP+JavaScript and freely available at http://sumosp.biocuckoo.org.
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[Effects of bladder neck preservation and reconstruction of rhabdosphincter on urinary continence recovery after laparoscopic radical prostatectomy].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 05-24-2014
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To retrospectively analyze the effects of bladder neck preservation (BNP) and reconstruction of rhabdosphincter (RS) on urinary continence recovery for patients after laparoscopic radical prostatectomy (LRP).
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Elevated autocrine EDIL3 protects hepatocellular carcinoma from anoikis through RGD-mediated integrin activation.
Mol. Cancer
PUBLISHED: 05-10-2014
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A remolded microenvironment in hepatocellular carcinoma (HCC) caused by abnormally expressed matricellular proteins could promote HCC progression. The cell-matrix interactions mediated by integrins play an important role in tumor microenvironment. Epidermal Growth Factor-like repeats and Discoidin I-Like Domains 3 (EDIL3), an extracellular matrix (ECM) protein with angiogenic and anti-inflammatory effects, is abnormally highly expressed in HCC. Here we aim to analyze its expression in liver and HCC tissues, investigate the underlined mechanisms accounted for HCC progression.
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Iodine mediated deprotection of N-tert-butanesulfinyl amines: a functional group compatible method.
Chem. Commun. (Camb.)
PUBLISHED: 05-01-2014
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In the presence of iodine, a functional group compatible method for the deprotection of tert-butanesulfinyl and p-toluenesulfinyl units was developed.
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[Effect of formula of removing both phlegm and blood stasis in improving hemorheology and blood fat of mini-swine with coronary heart disease of phlegm-stasis cementation syndrome].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 04-26-2014
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To observe effect of formula of removing both phlegm and blood stasis (TYTZ) in improving hemorheology and blood fat of mini-swine with coronary heart disease of phlegm-stasis cementation syndrome.
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[Effect of formula of removing both phlegm and blood stasis on inflammatory reaction in Chinese mini-swine with coronary atherosclerosis].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 04-26-2014
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To observe the effect of formula of removing both phlegm and blood stasis (TYTZ) in inhibiting the inflammatory reaction in Chinese mini-swine with coronary atherosclerosis.
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A carbon nanotube filled polydimethylsiloxane hybrid membrane for enhanced butanol recovery.
Sci Rep
PUBLISHED: 04-08-2014
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The carbon nanotubes (CNTs) filled polydimethylsiloxane (PDMS) hybrid membrane was fabricated to evaluate its potential for butanol recovery from acetone-butanol-ethanol (ABE) fermentation broth. Compared with the homogeneous PDMS membrane, the CNTs filled into the PDMS membrane were beneficial for the improvement of butanol recovery in butanol flux and separation factor. The CNTs acting as sorption-active sites with super hydrophobicity could give an alternative route for mass transport through the inner tubes or along the smooth surface. The maximum total flux and butanol separation factor reached up to 244.3 g/m(2)·h and 32.9, respectively, when the PDMS membrane filled with 10 wt% CNTs was used to separate butanol from the butanol/water solution at 80°C. In addition, the butanol flux and separation factor increased dramatically as temperature increased from 30°C to 80°C in feed solution since the higher temperature produced more free volumes in polymer chains to facilitate butanol permeation. A similar increase was also observed when butanol titer in solution increased from 10 g/L to 25 g/L. Overall, the CNTs/PDMS hybrid membrane with higher butanol flux and selectivity should have good potential for pervaporation separation of butanol from ABE fermentation broth.
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Hydration of the oxygen-evolving complex of photosystem II probed in the dark-stable S1 state using proton NMR dispersion profiles.
Phys Chem Chem Phys
PUBLISHED: 04-04-2014
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The hydration of the oxygen-evolving complex (OEC) was characterized in the dark stable S1 state of photosystem II using water R1(?) NMR dispersion (NMRD) profiles. The R1(?) NMRD profiles were recorded over a frequency range from 0.01 MHz to 40 MHz for both intact and Mn-depleted photosystem II core complexes from Thermosynechococcus vulcanus (T. vulcanus). The intact-minus-(Mn)-depleted difference NMRD profiles show a characteristic dispersion from approximately 0.03 MHz to 1 MHz, which is interpreted on the basis of the Solomon-Bloembergen-Morgan (SBM) and the slow motion theories as being due to a paramagnetic enhanced relaxation (PRE) of water protons. Both theories are qualitatively consistent with the ST = 1, g = 4.9 paramagnetic state previously described for the S1 state of the OEC; however, an alternative explanation involving the loss of a separate class of long-lived internal waters due to the Mn-depletion procedure can presently not be ruled out. Using a point-dipole approximation the PRE-NMRD effect can be described as being caused by 1-2 water molecules that are located about 10 Å away from the spin center of the Mn4CaO5 cluster in the OEC. The application of the SBM theory to the dispersion observed for PSII in the S1 state is questionable, because the parameters extracted do not fulfil the presupposed perturbation criterion. In contrast, the slow motion theory gives a consistent picture indicating that the water molecules are in fast chemical exchange with the bulk (?w < 1 ?s). The modulation of the zero-field splitting (ZFS) interaction suggests a (restricted) reorientation/structural equilibrium of the Mn4CaO5 cluster with a characteristic time constant of ?ZFS = 0.6-0.9 ?s.
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Water oxidation chemistry of a synthetic dinuclear ruthenium complex containing redox-active quinone ligands.
Inorg Chem
PUBLISHED: 04-02-2014
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We investigated theoretically the catalytic mechanism of electrochemical water oxidation in aqueous solution by a dinuclear ruthenium complex containing redox-active quinone ligands, [Ru2(X)(Y)(3,6-tBu2Q)2(btpyan)](m+) [X, Y = H2O, OH, O, O2; 3,6-tBu2Q = 3,6-di-tert-butyl-1,2-benzoquinone; btpyan =1,8-bis(2,2':6',2?-terpyrid-4'-yl)anthracene] (m = 2, 3, 4) (1). The reaction involves a series of electron and proton transfers to achieve redox leveling, with intervening chemical transformations in a mesh scheme, and the entire molecular structure and motion of the catalyst 1 work together to drive the catalytic cycle for water oxidation. Two substrate water molecules can bind to 1 with simultaneous loss of one or two proton(s), which allows pH-dependent variability in the proportion of substrate-bound structures and following pathways for oxidative activation of the aqua/hydroxo ligands at low thermodynamic and kinetic costs. The resulting bis-oxo intermediates then undergo endothermic O-O radical coupling between two Ru(III)-O(•) units in an anti-coplanar conformation leading to bridged ?-peroxo or ?-superoxo intermediates. The ?-superoxo species can liberate oxygen with the necessity for the preceding binding of a water molecule, which is possible only after four-electron oxidation is completed. The magnitude of catalytic current would be limited by the inherent sluggishness of the hinge-like bending motion of the bridged ?-superoxo complex that opens up the compact, hydrophobic active site of the catalyst and thereby allows water entry under dynamic conditions. On the basis of a newly proposed mechanism, we rationalize the experimentally observed behavior of electrode kinetics with respect to potential and discuss what causes a high overpotential for water oxidation by 1.
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Determination of damage-free crystal structure of an X-ray-sensitive protein using an XFEL.
Nat. Methods
PUBLISHED: 03-25-2014
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We report a method of femtosecond crystallography for solving radiation damage-free crystal structures of large proteins at sub-angstrom spatial resolution, using a large single crystal and the femtosecond pulses of an X-ray free-electron laser (XFEL). We demonstrated the performance of the method by determining a 1.9-Å radiation damage-free structure of bovine cytochrome c oxidase, a large (420-kDa), highly radiation-sensitive membrane protein.
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Disorganized vascular structures in sporadic venous malformations: a possible correlation with balancing effect between Tie2 and TGF-?.
Sci Rep
PUBLISHED: 03-18-2014
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Venous malformations (VMs) are among the most common slow-flow vascular malformations characterized by irregular venous channels, luminal thrombi, and phleboliths. To systematically manifest the disorganized vascular structures in sporadic VMs, we initially evaluated histopathological characteristics, perivascular cell coverage, adhesion molecules expression and vascular ultrastructures. Then, the expression of Tie2 and TGF-? in VMs was detected. Meanwhile, the in vitro studies were performed for mechanism investigation. Our data showed that the perivascular ?-SMA(+) cell coverage and expression of adhesion molecules in VMs were significantly decreased compared with those in the normal skin tissues. We also found that the expression and phosphorylation levels of Tie2 were upregulated, whereas TGF-? was downregulated in VMs, and they were negatively correlated. Moreover, the in vitro results also revealed a possible balancing effect between Tie2 and TGF-?, as demonstrated by the findings that Ang-1 (agonist of Tie2) treatment significantly downregulated TGF-? expression, and treatment with recombinant TGF-? could also suppress Tie2 expression and phosphorylation. This study provided strong evidence supporting the disorganized vascular structures and dysregulation of related molecules in sporadic VMs, and demonstrated a possible balancing effect between Tie2 and TGF-?, which might help to develop novel therapeutics for vascular disorganization-related disorders.
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Water exchange in manganese-based water-oxidizing catalysts in photosynthetic systems: from the water-oxidizing complex in photosystem II to nano-sized manganese oxides.
Biochim. Biophys. Acta
PUBLISHED: 03-15-2014
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The water-oxidizing complex (WOC), also known as the oxygen-evolving complex (OEC), of photosystem II in oxygenic photosynthetic organisms efficiently catalyzes water oxidation. It is, therefore, responsible for the presence of oxygen in the Earth's atmosphere. The WOC is a manganese-calcium (Mn?CaO?(H?O)?) cluster housed in a protein complex. In this review, we focus on water exchange chemistry of metal hydrates and discuss the mechanisms and factors affecting this chemical process. Further, water exchange rates for both the biological cofactor and synthetic manganese water splitting are discussed. The importance of fully unveiling the water exchange mechanism to understand the chemistry of water oxidation is also emphasized here. This article is part of a special issue entitled: photosynthesis research for sustainability: keys to produce clean energy.
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Pharmacological blockade of the MaxiK channel attenuates experimental acute pancreatitis and associated lung injury in rats.
Int. Immunopharmacol.
PUBLISHED: 03-13-2014
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Increasing evidence has recently demonstrated that soluble heparan sulfate (HS), a degradation product of extracellular matrix produced by elastase, plays a key role in the aggravation of acute pancreatitis (AP) and associated lung injury. However little is known about the detailed mechanism underlying HS-induced inflammatory cascade. Our previous work has provided a valuable clue that a large-conductance K(+) channel (MaxiK) was involved in the HS-stimulated activation of murine macrophages. Here we attempted to ask whether pharmacological inhibition of the MaxiK channel will exert beneficial effects on the treatment of AP and secondary lung injury. The protective effects of paxilline, a specific blocker of MaxiK, on rats against sodium taurocholate induced AP were evaluated. Our data showed that paxilline substantially attenuated AP and resultant lung injury, mainly by limiting the burst of inflammatory responses, as proven by decreased plasma concentrations of tumor necrosis factor-? and macrophage inflammatory protein-2, together with unimpaired pancreatic enzyme activities in rats suffering from AP. Compared with the therapeutic administration, pre-treatment of paxilline showed superior potential to slow down the progress of AP. Furthermore, AP rats received paxilline exhibited improved histopathologic alterations both in the pancreas and the lungs, and even lower lung MPO activity. Taken together, our study provides evidence that MaxiK is involved in the spread of inflammatory responses and the following lung injury during the attack of AP, indicating that this ion channel is a promising candidate as a therapeutic target for AP.
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Tissue accumulation and toxicity of isothiazolinone in Ctenopharyngodon idellus (grass carp): association with P-glycoprotein expression and location within tissues.
Environ. Toxicol. Pharmacol.
PUBLISHED: 02-25-2014
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Isothiazolinone is widely used as a broad-spectrum fungicide in various industries, such as oil, paper, pesticide, dyes, tanning and cosmetics. There is an increasing concern over protection of the aquatic environment due to its large-scale use. The acute toxicity (LC50) of isothiazolinone in Ctenopharyngodon idellus was investigated. The residual time and accumulation in tissues, P-glycoprotein mRNA level and localization of P-glycoprotein in the liver and kidney were also analyzed. The LC50 (48 h) values of isothiazolinone to C. idellus were 0.53±0.17 mg/L and 0.41±0.08 mg/L at 15 °C and 25 °C, respectively. The LC50 values decreased as the temperature increased. The accumulation of isothiazolinone in livers and kidneys in the high temperature group (25 °C) was significantly greater than that of the low temperature group (15 °C). Prolonged tissue residual time of isothiazolinone was seen in all the groups. There were significant differences in P-glycoprotein mRNA expression between isothiazolinone-treated groups and control samples (P<0.05-0.01). Temperature affected accumulation and toxicity of isothiazolinone.
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Monoamine oxidase A suppresses hepatocellular carcinoma metastasis by inhibiting the adrenergic system and its transactivation of EGFR signaling.
J. Hepatol.
PUBLISHED: 02-17-2014
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Monoamine oxidase A (MAOA), a catecholamine neurotransmitter degrading enzyme, is closely associated with neurological and psychiatric disorders. However, its role in cancer progression remains unknown.
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Systematic characterization of small RNAome during zebrafish early developmental stages.
BMC Genomics
PUBLISHED: 02-07-2014
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During early vertebrate development, various small non-coding RNAs (sRNAs) such as MicroRNAs (miRNAs) and Piwi-interacting RNAs (piRNAs) are dynamically expressed for orchestrating the maternal-to-zygotic transition (MZT). Systematic analysis of expression profiles of zebrafish small RNAome will be greatly helpful for understanding the sRNA regulation during embryonic development.
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Isolation and characterization of a PSI-LHCI super-complex and its sub-complexes from a siphonaceous marine green alga, Bryopsis Corticulans.
Photosyn. Res.
PUBLISHED: 01-26-2014
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A novel super-complex of photosystem I (PSI)-light-harvesting complex I (LHCI) was isolated from a siphonaceous marine green alga, Bryopsis corticulans. The super-complex contained 9-10 Lhca antennas as external LHCI bound to the core complex. The super-complex was further disintegrated into PSI core and LHCI sub-complexes, and analysis of the pigment compositions by high-performance liquid chromatography revealed unique characteristics of the B. corticulans PSI in that one PSI core contained around 14 ?-carotenes and 1-2 ?-carotenes. This is in sharp contrast to the PSI core from higher plants and most cyanobacteria where only ?-carotenes were present, and is the first report for an ?-carotene-type PSI core complex among photosynthetic eukaryotes, suggesting a structural flexibility of the PSI core. Lhca antennas from B. corticulans contained seven kinds of carotenoids (siphonaxanthin, all-trans neoxanthin, 9'-cis neoxanthin, violaxanthin, siphonein, ?-carotene, and ?-carotene) and showed a high carotenoid:chlorophyll ratio of around 7.5:13. PSI-LHCI super-complex and PSI core showed fluorescence emission peaks at 716 and 718 nm at 77 K, respectively; whereas two Lhca oligomers had fluorescence peaks at 681 and 684 nm, respectively. By comparison with spinach PSI preparations, it was found that B. corticulans PSI had less red chlorophylls, most of them are present in the core complex but not in the outer light-harvesting systems. These characteristics may contribute to the fine tuning of the energy transfer network, and to acclimate to the ever-changing light conditions under which the unique green alga inhabits.
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A nano-sized manganese oxide in a protein matrix as a natural water-oxidizing site.
Plant Physiol. Biochem.
PUBLISHED: 01-26-2014
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The purpose of this review is to present recent advances in the structural and functional studies of water-oxidizing center of Photosystem II and its surrounding protein matrix in order to synthesize artificial catalysts for production of clean and efficient hydrogen fuel.
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Polymorphism of heat shock protein 70-2 and enterocutaneous fistula in Chinese population.
World J. Gastroenterol.
PUBLISHED: 01-20-2014
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To investigate whether the heat shock protein 70-2 (HSP70-2) polymorphism is associated with enterocutaneous fistulas in a Chinese population.
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Acid-sensing ion channels activation and hypoxia upregulate Homer1a expression.
CNS Neurosci Ther
PUBLISHED: 01-17-2014
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Recent studies have indicated that dynamic alterations in the structure of postsynaptic density (PSD) are involved in the pathogenesis of many central nervous system disorders, including ischemic stroke. Homer is the newly identified scaffolding protein located at PSD and regulates synaptic function. Homer1a, an immediate early gene, has been shown to be induced by several stimulations, such as glutamate, brain-derived neurotrophic factor, and trauma. However, whether acidosis mediated by acid-sensing ion channels (ASICs) and hypoxia during cerebral ischemia can change Homer1a expression remains to be determined.
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Zuo Jin Wan reverses P-gp-mediated drug-resistance by inhibiting activation of the PI3K/Akt/NF-?B pathway.
BMC Complement Altern Med
PUBLISHED: 01-11-2014
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Zuo-Jin-Wan (ZJW), a traditional Chinese medicine formula, has been identified to be effective against drug resistance in cancer. In the present study, we investigated the effect of ZJW on acquired oxaliplatin-resistant and the PI3K/Akt/NF-?B pathway in vitro.
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An integrated overview of spatiotemporal organization and regulation in mitosis in terms of the proteins in the functional supercomplexes.
Front Microbiol
PUBLISHED: 01-01-2014
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Eukaryotic cells may divide via the critical cellular process of cell division/mitosis, resulting in two daughter cells with the same genetic information. A large number of dedicated proteins are involved in this process and spatiotemporally assembled into three distinct super-complex structures/organelles, including the centrosome/spindle pole body, kinetochore/centromere and cleavage furrow/midbody/bud neck, so as to precisely modulate the cell division/mitosis events of chromosome alignment, chromosome segregation and cytokinesis in an orderly fashion. In recent years, many efforts have been made to identify the protein components and architecture of these subcellular organelles, aiming to uncover the organelle assembly pathways, determine the molecular mechanisms underlying the organelle functions, and thereby provide new therapeutic strategies for a variety of diseases. However, the organelles are highly dynamic structures, making it difficult to identify the entire components. Here, we review the current knowledge of the identified protein components governing the organization and functioning of organelles, especially in human and yeast cells, and discuss the multi-localized protein components mediating the communication between organelles during cell division.
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Comparative physiological and proteomic analyses of poplar (Populus yunnanensis) plantlets exposed to high temperature and drought.
PLoS ONE
PUBLISHED: 01-01-2014
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Plantlets of Populus yunnanensis Dode were examined in a greenhouse for 48 h to analyze their physiological and proteomic responses to sustained heat, drought, and combined heat and drought. Compared with the application of a single stress, simultaneous treatment with both stresses damaged the plantlets more heavily. The plantlets experienced two apparent response stages under sustained heat and drought. During the first stage, malondialdehyde and reactive oxygen species (ROS) contents were induced by heat, but many protective substances, including antioxidant enzymes, proline, abscisic acid (ABA), dehydrin, and small heat shock proteins (sHSPs), were also stimulated. The plants thus actively defended themselves against stress and exhibited few pathological morphological features, most likely because a new cellular homeostasis was established through the collaborative operation of physiological and proteomic responses. During the second stage, ROS homeostasis was overwhelmed by substantial ROS production and a sharp decline in antioxidant enzyme activities, while the synthesis of some protective elements, such as proline and ABA, was suppressed. As a result, photosynthetic levels in P. yunnanensis decreased sharply and buds began to die, despite continued accumulation of sHSPs and dehydrin. This study supplies important information about the effects of extreme abiotic environments on woody plants.
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Serum TFF3 may be a pharamcodynamic marker of responses to chemotherapy in gastrointestinal cancers.
BMC Clin Pathol
PUBLISHED: 01-01-2014
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As a secreted protein, serum trefoil factor 3 (TFF3) has been reported to be a biomarker of several malignancies. We further investigated whether TFF3 can be applied as a biomarker for and predictor of responses to chemotherapy in gastrointestinal cancer.
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Endovascular Treatment of an Unusual Primary Arterioportal Fistula Complicated by Cavernous Transformation of the Portal Vein Caused by Portal Thrombosis.
Ann Vasc Surg
PUBLISHED: 12-22-2013
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We describe an elderly woman who presented with an unusual primary arterioportal fistula and cavernous transformation of the portal vein caused by portal thrombosis, which were subsequently managed with endovascular coil embolization and transjugular intrahepatic portosystemic shunt using 2 stents after balloon remodeling. This case shows a rarely seen condition in the elderly and a novel management strategy that should be considered in the management of this complex disease.
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[Clinical value of iodine [131I] metuximab infusion combined with TACE for treatment of patients with post-intervention relapse of mid or advanced stage hepatocellular carcinoma].
Zhonghua Gan Zang Bing Za Zhi
PUBLISHED: 12-17-2013
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To evaluate the clinical value of iodine[131I] metuximab infusion combined with transcatheter arterial chemoembolization (TACE) for treating cases of post-intervention relapse of mid or advanced stage hepatocellular carcinoma (HCC).
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Evidence for an Unprecedented Histidine Hydroxyl Modification on D2-His336 in Photosystem II of Thermosynechoccocus vulcanus and Thermosynechoccocus elongatus.
Biochemistry
PUBLISHED: 12-17-2013
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The electron density map of the 3D crystal of Photosystem II from Thermosynechococcus vulcanus with a 1.9 Å resolution (PDB: 3ARC ) exhibits, in the two monomers in the asymmetric unit cell, an, until now, unidentified and uninterpreted strong difference in electron density centered at a distance of around 1.5 Å from the nitrogen N? of the imidazole ring of D2-His336. By MALDI-TOF/MS upon tryptic digestion, it is shown that ?20-30% of the fragments containing the D2-His336 residue of Photosystem II from both Thermosynechococcus vulcanus and Thermosynechococcus elongatus bear an extra mass of +16 Da. Such an extra mass likely corresponds to an unprecedented post-translational or chemical hydroxyl modification of histidine.
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Assessment of 64-row computed tomographic angiography for diagnosis and pretreatment planning in pulmonary sequestration.
Radiol Med
PUBLISHED: 11-15-2013
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This study was done to evaluate the clinical implications and results of a prospective protocol using 64-row computed tomographic angiography (CTA) for diagnosis and pre-treatment planning in pulmonary sequestration (PS).
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CPLM: a database of protein lysine modifications.
Nucleic Acids Res.
PUBLISHED: 11-08-2013
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We reported an integrated database of Compendium of Protein Lysine Modifications (CPLM; http://cplm.biocuckoo.org) for protein lysine modifications (PLMs), which occur at active ?-amino groups of specific lysine residues in proteins and are critical for orchestrating various biological processes. The CPLM database was updated from our previously developed database of Compendium of Protein Lysine Acetylation (CPLA), which contained 7151 lysine acetylation sites in 3311 proteins. Here, we manually collected experimentally identified substrates and sites for 12 types of PLMs, including acetylation, ubiquitination, sumoylation, methylation, butyrylation, crotonylation, glycation, malonylation, phosphoglycerylation, propionylation, succinylation and pupylation. In total, the CPLM database contained 203 972 modification events on 189 919 modified lysines in 45 748 proteins for 122 species. With the dataset, we totally identified 76 types of co-occurrences of various PLMs on the same lysine residues, and the most abundant PLM crosstalk is between acetylation and ubiquitination. Up to 53.5% of acetylation and 33.1% of ubiquitination events co-occur at 10 746 lysine sites. Thus, the various PLM crosstalks suggested that a considerable proportion of lysines were competitively and dynamically regulated in a complicated manner. Taken together, the CPLM database can serve as a useful resource for further research of PLMs.
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[Retroperitoneal laparoscopic decortication and adrenalectomy for the therapy of adrenal cysts].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 10-31-2013
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To summarize the clinical characteristics of adrenal cysts and compare the therapeutic results of two different laparoscopic surgical techniques.
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Unexpected development of tongue squamous cell carcinoma after sclerotherapy for the venous malformation: a unique case report and literature review.
Diagn Pathol
PUBLISHED: 09-21-2013
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Sclerotherapy is a common and effective treatment for venous diseases, including venous malformations (VMs), which are common vascular anomalies in the oral and maxillofacial regions. However, the safety of sclerotherapy has not been fully elucidated. Occasionally, patients who underwent sclerotherapy may present diverse but minor side effects such as erythema, swelling, pain, tenderness, hyperpigmentation, skin ulceration and necrosis.
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Thermoresponsive microgel films for harvesting cells and cell sheets.
Biomacromolecules
PUBLISHED: 09-13-2013
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This work reports the formation of thermoresponsive poly(N-isopropylacrylamide-co-styrene) (PNIPAAmSt) microgel films and their use for cell growth and detachment via temperature stimuli. Thermoresponsive surface films can be conveniently produced by spin-coating or drop-coating of PNIPAAmSt microgel dispersions onto substrates such as glass coverslips, cell culture plates, and flasks, making this technique widely accessible. The thickness, stability, and reversibility of the PNIPAAmSt films coated on silicon wafers with respect to temperature switching were examined by spectroscopic ellipsometry (SE) and atomic force microscopy (AFM). The results unraveled the direct link between thermoreversibility and changes in film thickness and surface morphology, showing reversible hydration and dehydration. Under different coating conditions, well-packed microgel monolayers could be utilized for effective cell recovery and harvesting. Furthermore, cell adhesion and detachment processes were reversible and there was no sign of loss of cell viability during repeated surface attachment, growth, and detachment, showing a mild interaction between cells and thermoresponsive surface. More importantly, there was little deterioration of the packing of the thermoresponsive films or any major loss of microgel particles during reuse, indicating their robustness. These PNIPAAmSt microgel films thus open up a convenient interfacial platform for cell and cell sheet harvesting while avoiding the damage of enzymatic cleavage.
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Crystal structure of Psb31, a novel extrinsic protein of photosystem II from a marine centric diatom and implications for its binding and function.
Biochemistry
PUBLISHED: 09-11-2013
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Psb31 is a fifth extrinsic protein found in photosystem II (PSII) of a centric diatom, Chaetoceros gracilis . The protein has been shown to bind directly to PSII in the absence of other extrinsic proteins and serves in part as a substitute for PsbO in supporting oxygen evolution. We report here the crystal structure of Psb31 at a resolution of 1.55 Å. The structure of Psb31 was composed of two domains, one major, N-terminal four helical domain and one minor, flexible C-terminal domain. The four helices in the N-terminal domain were arranged in an up-down-up-down fold, which appeared unexpectedly to be similar to the structure of spinach PsbQ, in spite of their low sequence homology. This suggests that the centric diatom PSII contains another PsbQ-type extrinsic protein in addition to the original PsbQ protein found in the organism. On the other hand, the C-terminal domain of Psb31 has a unique structure composed of one loop and one short helix. Based on these structural analysis and chemical cross-linking experiments, residues responsible for the binding of Psb31 to PSII intrinsic proteins were suggested. The results are discussed in relation to the copy number of extrinsic proteins in higher plant PSII.
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MUC1 activates JNK1 and inhibits apoptosis under genotoxic stress.
Biochem. Biophys. Res. Commun.
PUBLISHED: 09-04-2013
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The MUC1 transmembrane glycoprotein is aberrantly overexpressed in diverse human carcinomas and has been shown to inhibit apoptosis induced by genotoxic agents. In the present work, we report that MUC1 binds to and activates JNK1, an important member of the mitogen-activated protein kinases (MAPK) superfamily. The physical interaction between MUC1 cytoplasmic domain (MUC1-CD) and JNK1 was established by GST-pull-down assay in vitro and co-immunoprecipitation assay in vivo. We show that MUC1 activates JNK1 and inhibits cisplatin-induced apoptosis in human colon cancer HCT116 cells. Pharmacological inhibition of JNK or knockdown of JNK significantly reduces the ability of MUC1 to inhibit cisplatin-induced apoptosis. Together, our data indicate that MUC1 can inhibit apoptosis via activating JNK1 pathway in response to genotoxic anticancer agents.
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Application of peptide gemini surfactants as novel solubilization surfactants for photosystems I and II of cyanobacteria.
Langmuir
PUBLISHED: 09-04-2013
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We designed novel peptide gemini surfactants (PG-surfactants), DKDKC12K and DKDKC12D, which can solubilize Photosystem I (PSI) of Thermosynecoccus elongatus and Photosystem II (PSII) of Thermosynecoccus vulcanus in an aqueous buffer solution. To assess the detailed effects of PG-surfactants on the original supramolecular membrane protein complexes and functions of PSI and PSII, we applied the surfactant exchange method to the isolated PSI and PSII. Spectroscopic properties, light-induced electron transfer activity, and dynamic light scattering measurements showed that PSI and PSII could be solubilized not only with retention of the original supramolecular protein complexes and functions but also without forming aggregates. Furthermore, measurement of the lifetime of light-induced charge-separation state in PSI revealed that both surfactants, especially DKDKC12D, displayed slight improvement against thermal denaturation below 60 °C compared with that using ?-DDM. This degree of improvement in thermal resistance still seems low, implying that the peptide moieties did not interact directly with membrane protein surfaces. By conjugating an electron mediator such as methyl viologen (MV(2+)) to DKDKC12K (denoted MV-DKDKC12K), we obtained derivatives that can trap the generated reductive electrons from the light-irradiated PSI. After immobilization onto an indium tin oxide electrode, a cathodic photocurrent from the electrode to the PSI/MV-DKDKC12K conjugate was observed in response to the interval of light irradiation. These findings indicate that the PG-surfactants DKDKC12K and DKDKC12D provide not only a new class of solubilization surfactants but also insights into designing other derivatives that confer new functions on PSI and PSII.
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M2-polarised macrophages in infantile haemangiomas: correlation with promoted angiogenesis.
J. Clin. Pathol.
PUBLISHED: 08-28-2013
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The pathogenesis of infantile haemangiomas (IHs) is still far from clear despite the fact that they are common vascular tumours distinctive for their perinatal presentation, rapid growth during the first year of life and subsequent slow involution.
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Effect of different drying methods on chemical composition and bioactivity of tea polysaccharides.
Int. J. Biol. Macromol.
PUBLISHED: 07-23-2013
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Four polysaccharides (TPS-F, TPS-V, TPS-S and TPS-M) were obtained from tea (Camellia sinensis) leaves by freeze-drying, vacuum-drying, spray-drying and microwave-vacuum drying, respectively. Their chemical composition and biological properties were comparatively studied. The results showed these TPS were similar in IR, UV absorption and distribution of molecular weight. However, they showed significant differences (P<0.05) in yields of crude polysaccharides and contents of protein and total polyphenols. Furthermore, morphological analysis showed their surface differed from each other in size and shape when viewed by SEM, from which surface of TPS-F was rough and porous, surface of TPS-S was evenly particles, and surfaces of the other two were similar to anomalistic bricks. In addition, the bioactivity of them was also evaluated. It was found TPS-F exhibited relatively better ability on metal chelating and superoxide radicals scavenging assays than others, and TPS-V exhibited higher ability on ?-glycosidase and ?-amylase inhibition assays than others with inhibitory percentages of 82.75% and 92.8%.
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Limitations in the application of the Gibbs equation to anionic surfactants at the air/water surface: sodium dodecylsulfate and sodium dodecylmonooxyethylenesulfate above and below the CMC.
Langmuir
PUBLISHED: 07-16-2013
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This is a second paper responding to recent papers by Menger et al. and the ensuing discussion about the application of the Gibbs equation to surface tension (ST) data. Using new neutron reflection (NR) measurements on sodium dodecylsulfate (SDS) and sodium dodecylmonooxyethylene sulfate (SLES) above and below their CMCs and with and without added NaCl, in conjunction with the previous ST measurements on SDS by Elworthy and Mysels (EM), we conclude that (i) ST measurements are often seriously compromised by traces of divalent ions, (ii) adsorption does not generally reach saturation at the CMC, making it difficult to obtain the limiting Gibbs slope, and (iii) the significant width of micellization may make it impossible to apply the Gibbs equation in a significant range of concentration below the CMC. Menger et al. proposed ii as a reason for the difficulty of applying the Gibbs equation to ST data. Conclusions i and iii now further emphasize the failings of the ST-Gibbs analysis for determining the limiting coverage at the CMC, especially for SDS. For SDS, adsorption increases above the CMC to a value of 10 × CMC, which is about 25% greater than at the CMC and about the same as at the CMC in the presence of 0.1 M NaCl. In contrast, the adsorption of SLES reaches a limit at the CMC with no further increase up to 10 × CMC, but the addition of 0.1 M NaCl increases the surface excess by 20-25%. The results for SDS are combined with earlier NR results to generate an adsorption isotherm from 2 to 100 mM. The NR results for SDS are compared to the definitive surface tension (ST) measurements of EM, and the surface excesses agree over the range where they can safely be compared, from 2 to 6 mM. This confirms that the anomalous decrease in the slope of EMs ? - ln c curve between 6 mM and the CMC at 8.2 mM results from changes in activity associated with a significant width of micellization. This anomaly shows that it is impossible to apply the Gibbs equation usefully from 6 to 8.2 mM (i.e., the lack of knowledge of the activity in this range is the same as above the CMC (8.2 mM)). It was found that a mislabeling of the original data in EM may have prevented the use of this excellent ST data as a standard by other authors. Although NR and ST results for SDS in the absence of added electrolyte show that the discrepancies can be rationalized, ST is generally shown to be less accurate and more vulnerable to impurities, especially divalent ions, than NR. The radiotracer technique is shown to be less accurate than ST-Gibbs in that the four radiotracer measurements of the surface excess are consistent neither with each other nor with ST and NR. It is also shown that radiotracer results on aerosol-OT are likely to be incorrect. Application of the mass action (MA) model of micellization to the ST curves of SDS and SLES through and above the CMC shows that they can be explained by this model and that they depend on the degree of dissociation of the micelle, which leads to a larger change in the mean activity, and hence the adsorption, for the more highly dissociated SDS micelles than for SLES. Previous measurements of the activity of SDS above the CMC were found to be semiquantitatively consistent with the change in mean activity predicted by the MA model but inconsistent with the combined ST, NR, and Gibbs equation results.
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Determination of the PS I content of PS II core preparations using selective emission: A new emission of PS II at 780nm.
Biochim. Biophys. Acta
PUBLISHED: 07-12-2013
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Routinely prepared PS II core samples are often contaminated by a significant (~1-5%) fraction of PS I, as well as related proteins. This contamination is of little importance in many experiments, but masks the optical behaviour of the deep red state in PS II, which absorbs in the same spectral range (700-730nm) as PS I (Hughes et al. 2006). When contamination levels are less than ~1%, it becomes difficult to quantify the PS I related components by gel-based, chromatographic, circular dichroism or EPR techniques. We have developed a fluorescence-based technique, taking advantage of the distinctively different low-temperature emission characteristics of PS II and PS I when excited near 700nm. The approach has the advantage of providing the relative concentration of the two photosystems in a single spectral measurement. A sensitivity limit of 0.01% PS I (or better) can be achieved. The procedure is applied to PS II core preparations from spinach and Thermosynechococcus vulcanus. Measurements made of T. vulcanus PS II preparations prepared by re-dissolving crystallised material indicate a low but measurable PS I related content. The analysis provides strong evidence for a previously unreported fluorescence of PS II cores peaking near 780nm. The excitation dependence of this emission as well as its appearance in both low PS I cyanobacterial and plant based PS II core preparations suggests its association with the deep red state of PS II.
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Crystal structure at 1.5Å resolution of the PsbV2 cytochrome from the cyanobacterium Thermosynechococcus elongatus.
FEBS Lett.
PUBLISHED: 07-11-2013
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PsbV2 is a c-type cytochrome present in a very low abundance in the thermophilic cyanobacterium Thermosynechococcus elongatus. We purified this cytochrome and solved its crystal structure at a resolution of 1.5Å. The protein existed as a dimer in the crystal, and has an overall structure similar to other c-type cytochromes like Cytc6 and Cytc550, for example. However, the 5th and 6th heme iron axial ligands were found to be His51 and Cys101, respectively, in contrast to the more common bis-His or His/Met ligands found in most cytochromes. Although a few other c-type cytochromes were suggested to have this axial coordination, this is the first crystal structure reported for a c-type heme with this unusual His/Cys axial coordination. Previous spectroscopic characterizations of PsbV2 are discussed in relation to its structural properties.
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Application of the Gibbs equation to the adsorption of nonionic surfactants and polymers at the air-water interface: comparison with surface excesses determined directly using neutron reflectivity.
Langmuir
PUBLISHED: 06-25-2013
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Four recent papers by Menger et al. have questioned methods of analysis of surface tension (ST) data that use the Gibbs equation to obtain the surface excess (?) of a surfactant at the air-water interface. There have been two responses which challenge the assertions of Menger et al. and a response from Menger et al. We use directly determined values of ? from a range of neutron reflectometry (NR) data to examine some of the issues that are relevant to these seven papers. We show that there is excellent agreement between NR measurements and careful ST analyses for a wide range of nonionic adsorbents, including surfactants and polymers. The reason it is possible to obtain good agreement near the critical micelle concentration (CMC) is that nonionic surfactants generally seem to saturate the surface before the CMC is reached and this makes it relatively easy to determine the limiting slope (and hence ?) of the ST-log(concentration) plot at the CMC. Furthermore, there is also generally good agreement between ST and NR over the whole range of concentrations below the CMC until depletion effects become important. Depletion effects are shown to become important at higher concentrations than expected, which brings them into the range of many experiments, including techniques other than ST and NR. This is illustrated with new measurements on the biosurfactant surfactin. The agreement between ST and NR outside the depletion range can be regarded as a mutual validation of the two methods, especially as it is demonstrated independently of any model adsorption isotherms. In the normal experimental situation NR is less vulnerable to depletion than ST and we show how NR and a single ST measurement can be used to determine the hitherto undetermined CMC of the nonionic surfactant C18E12, which is found to be 1.3 × 10(-6) M.
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Towards a better understanding of the novel avian-origin H7N9 influenza A virus in China.
Sci Rep
PUBLISHED: 05-14-2013
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Recently, a highly dangerous bird flu has infected over 130 patients in China, and the outbreak was attributed to a novel avian-origin H7N9 virus. Here, we performed a systematic analysis of the virus. We clarified the controversial viewpoint on neuraminidase (NA) origin and confirmed it was reassorted from Korean wild birds with higher confidence, whereas common ancestors of pathogenic H7N9 genes existed only one or two years ago. Further analysis of NA sequences suggested that most variations are not drug resistant and current drugs are still effective for the therapy. We also identified a potentially optimal 9-mer epitope, which can be helpful for vaccine development. The interaction of hemagglutinin (HA) and human receptor analog was confirmed by structural modeling, while NA might influence cellular processes through a PDZ-binding motif. A simplified virus infection model was proposed. Taken together, our studies provide a better understanding of the newly reassorted H7N9 viruses.
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Bleomycin induces endothelial mesenchymal transition through activation of mTOR pathway: a possible mechanism contributing to the sclerotherapy of venous malformations.
Br. J. Pharmacol.
PUBLISHED: 05-05-2013
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Bleomycin, one of the most common sclerosants, is often employed in the treatment of venous malformations (VMs). The present study is designed to investigate whether endothelial mesenchymal transition (EndoMT) contributes to the therapeutic effects of bleomycin.
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[Theoretical and clinical application of insomnia caused by "stomach disorder could lead to excess of yang-qiao meridian"].
Zhongguo Zhen Jiu
PUBLISHED: 04-30-2013
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To explore the mechanism of insomnia caused by "stomach disorder could lead to excess of yang-qiao meridian" and clinical application of treating insomnia with acupoints in qiao meridian as the main points. From meridian theory, intersection between stomach meridian of Foot-Yangming and yang-qiao meridian is through Chengqi (ST 1). Qiao meridian for sleep is mainly because it is connected with eyes through the Bladder Meridian of Foot-Taiyang. For Stomach Meridian of Foot-Yangming is intersected with the Bladder Meridian of Foot-Taiyang in Jingming (BL 1), and intersected with yin and yang qiao meridian beside the mouth and under the eye, once functional disorder of the stomach, it can affect qi movements of the whole body and give rise to various pathological changes that cause insomnia. Meanwhile examples are given to explain the clinical application of treating subborn insomnia with corresponding acupoint of stomach and yang-qiao meridian.
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Exome Sequencing Revealed Novel Germline Mutations in Chinese Peutz-Jeghers Syndrome Patients.
Dig. Dis. Sci.
PUBLISHED: 04-26-2013
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Peutz-Jeghers Syndrome (PJS) is an autosomal dominant disorder which predisposes to the development of various cancers. Germline mutation in the serine/threonine kinase 11 gene (STK11) is known as one of the major causes of PJS. However, a notable proportion of PJS samples do not carry any mutation in STK11, suggesting possible genetic heterogeneity in the disease and the existence of other causative variants.
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[Pathogenesis, diagnosis and treatment of anemia in inflammatory bowel disease].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 04-24-2013
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Anemia is a common and severe complication in inflammatory bowel disease. Anemia can induce impaired cardiovascular and renal functions, and lead to a significantly decreased quality of life. This review is dedicated to explain the underlying mechanism, diagnosis and management of anemia in inflammatory bowel disease.
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Photosystem II does not possess a simple excitation energy funnel: time-resolved fluorescence spectroscopy meets theory.
J. Am. Chem. Soc.
PUBLISHED: 04-24-2013
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The experimentally obtained time-resolved fluorescence spectra of photosystem II (PS II) core complexes, purified from a thermophilic cyanobacterium Thermosynechococcus vulcanus, at 5-180 K are compared with simulations. Dynamic localization effects of excitons are treated implicitly by introducing exciton domains of strongly coupled pigments. Exciton relaxations within a domain and exciton transfers between domains are treated on the basis of Redfield theory and generalized Förster theory, respectively. The excitonic couplings between the pigments are calculated by a quantum chemical/electrostatic method (Poisson-TrEsp). Starting with previously published values, a refined set of site energies of the pigments is obtained through optimization cycles of the fits of stationary optical spectra of PS II. Satisfactorily agreement between the experimental and simulated spectra is obtained for the absorption spectrum including its temperature dependence and the linear dichroism spectrum of PS II core complexes (PS II-CC). Furthermore, the refined site energies well reproduce the temperature dependence of the time-resolved fluorescence spectrum of PS II-CC, which is characterized by the emergence of a 695 nm fluorescence peak upon cooling down to 77 K and the decrease of its relative intensity upon further cooling below 77 K. The blue shift of the fluorescence band upon cooling below 77 K is explained by the existence of two red-shifted chlorophyll pools emitting at around 685 and 695 nm. The former pool is assigned to Chl45 or Chl43 in CP43 (Chl numbering according to the nomenclature of Loll et al. Nature2005, 438, 1040) while the latter is assigned to Chl29 in CP47. The 695 nm emitting chlorophyll is suggested to attract excitations from the peripheral light-harvesting complexes and might also be involved in photoprotection.
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Progressive balloon dilatation following hepaticojejunostomy improves outcome of bile duct stricture after iatrogenic biliary injury.
BMC Gastroenterol
PUBLISHED: 04-17-2013
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Iatrogenic biliary stricture (IBS) is a disastrous complication of cholecystectomy. Although the endoscopic treatments are well accepted as initial attempts for IBS, surgical hepaticojejunostomy (HJ) is often necessary for a considerable proportion of patients. However, the anastomotic stricture after HJ also occurs.
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Shenfu injection () suppresses inflammation by targeting haptoglobin and pentraxin 3 in rats with chronic ischemic heart failure.
Chin J Integr Med
PUBLISHED: 03-15-2013
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OBJECTIVE: To investigate the regulatory effects of Shenfu Injection (SFI, ) on hemodynamic parameters and serum proteins in rats with post-infarction chronic heart failure (CHF). METHODS: Forty-five healthy Wistar rats were randomized into three groups: sham, heart failure (model) and SFI group. The CHF was induced by left coronary artery ligation. Seven days after the surgical operation, animals in the sham group and the model group received saline (6.2 mL/kg/d), while animals in the SFI group received SFI (6.2 mL/kg d) intraperitoneally. Four weeks later, cardiac hemodynamic parameters were measured via the carotid route. The expression of serum proteins was analyzed by two-dimensional electrophoresis and matrixassisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS). RESULTS: Recording of hemodynamic parameters showed that left ventricular systolic pressure (LVSP), maximum rate of left ventricular pressure (+dp/dtmax) rise, and maximum rate of left ventricular pressure (-dp/dtmax) decrease, while the left ventricular end diastolic pressure (LVEDP) rose in the model group compared to those in the sham group (P<0.05). The results of the MALDI-TOF MS indicated that haptoglobin (HP), pentraxin 3 (PTX3) and alpha-1-antitrypsin were up-regulated, while serum albumin and 40S ribosomal protein were down-regulated in the model group (P<0.05). Compared with the model group, LVSP, +dp/dtmax and -dp/dtmax were higher, while LVEDP was lower in the SFI group (P<0.05). Expression levels of HP and PTX3 were lower than in the model group (P<0.05). CONCLUSION: SFI could improve hemodynamic function and decrease inflammatory reactions in the pathophysiology of CHF. The serum proteins HP and PTX3 could be potential biomarkers for chronic ischemic heart failure, and they could also be the serum protein targets of SFI.
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Gold or silver deposited on layered manganese oxide: a functional model for the water-oxidizing complex in photosystem II.
Photosyn. Res.
PUBLISHED: 03-11-2013
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In this report, gold or silver deposited on layered manganese oxide has been synthesized by a simple method and characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction spectrometry, atomic absorption spectroscopy, and energy-dispersive X-ray mapping. The gold deposited on layered manganese oxide showed efficient catalytic activity toward water oxidation in the presence of cerium(IV) ammonium nitrate. The properties associated with this compound suggest it is a functional model for the water-oxidizing complex in photosystem II.
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Spectral and functional studies on siphonaxanthin-type light-harvesting complex of photosystem II from Bryopsis corticulans.
Photosyn. Res.
PUBLISHED: 03-02-2013
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Carotenoids with conjugated carbonyl groups possess special photophysical properties which have been studied in some water-soluble light-harvesting proteins (Polívka and Sundström, Chem Rev 104:2021-2071, 2004). However, siphonaxanthin-type light-harvesting complexes of photosystem II (LHCII) in siphonous green alga have received fewer studies. In the present study, we determined sequences of genes for several Bryopsis corticulans Lhcbm proteins, which showed that they belong to the group of major LHCII and diverged early from green algae and higher plants. Analysis of pigment composition indicated that this siphonaxanthin-type LHCII contained in total 3 siphonaxanthin and siphonein but no lutein and violaxanthin. In addition, 2 chlorophylls a in higher plant LHCII were replaced by chlorophyll b. These changes led to an increased absorption in green and blue-green light region compared with higher plant LHCII. The binding sites for chlorophylls, siphonaxanthin, and siphonein were suggested based on the structural comparison with that of higher plant LHCII. All of the ligands for the chlorophylls were completely conserved, suggesting that the two chlorophylls b were replaced by chlorophyll a without changing their binding sites in higher plant LHCII. Comparisons of the absorption spectra of isolated siphonaxanthin and siphonein in different organic solutions and the effect of heat treatment suggested that these pigments existed in a low hydrophobic protein environment, leading to an enhancement of light harvesting in the green light region. This low hydrophobic protein environment was maintained by the presence of more serine and threonine residues in B. corticulans LHCII. Finally, esterization of siphonein may also contribute to the enhanced harvesting of green light.
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Structure of Sr-substituted photosystem II at 2.1 A resolution and its implications in the mechanism of water oxidation.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 02-20-2013
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Oxygen-evolving complex of photosystem II (PSII) is a tetra-manganese calcium penta-oxygenic cluster (Mn4CaO5) catalyzing light-induced water oxidation through several intermediate states (S-states) by a mechanism that is not fully understood. To elucidate the roles of Ca(2+) in this cluster and the possible location of water substrates in this process, we crystallized Sr(2+)-substituted PSII from Thermosynechococcus vulcanus, analyzed its crystal structure at a resolution of 2.1 Å, and compared it with the 1.9 Å structure of native PSII. Our analysis showed that the position of Sr was moved toward the outside of the cubane structure of the Mn4CaO5-cluster relative to that of Ca(2+), resulting in a general elongation of the bond distances between Sr and its surrounding atoms compared with the corresponding distances in the Ca-containing cluster. In particular, we identified an apparent elongation in the bond distance between Sr and one of the two terminal water ligands of Ca(2+), W3, whereas that of the Sr-W4 distance was not much changed. This result may contribute to the decrease of oxygen evolution upon Sr(2+)-substitution, and suggests a weak binding and rather mobile nature of this particular water molecule (W3), which in turn implies the possible involvement of this water molecule as a substrate in the O-O bond formation. In addition, the PsbY subunit, which was absent in the 1.9 Å structure of native PSII, was found in the Sr-PSII structure.
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Index-based dietary patterns and risk of esophageal and gastric cancer in a large cohort study.
Clin. Gastroenterol. Hepatol.
PUBLISHED: 02-15-2013
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Diet could affect risk for esophageal and gastric cancers, but associations have been inconsistent. The diet is complex, so studies of dietary patterns, rather than studies of individual foods, might be more likely to identify cancer risk factors. There is limited research on index-based dietary patterns and esophageal and gastric cancers. We prospectively evaluated associations between the Healthy Eating Index-2005 (HEI-2005) and alternate Mediterranean Diet (aMED) scores and risk of esophageal and gastric cancers.
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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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