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Find video protocols related to scientific articles indexed in Pubmed.
Rewards and unique challenges faced by African-American custodial grandmothers: the importance of future planning.
Aging Ment Health
PUBLISHED: 10-28-2014
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Objectives: This exploratory study examined the context and consequences of custodial grandparenting, along with attitudes and preferences regarding future planning among 22 African-American custodial grandmothers. Method: A mixed-method research design was employed. Based on our integration of two theories regarding future planning and health behavior change, caregiving, emotional distress, religiosity and spirituality, and future planning were assessed using questionnaires along with semi-structured interviews. Results: African-American custodial grandmothers (mean age M = 53.64, SD = 9.58) perceived their caregiving role as rewarding (72%) yet challenging (86%). More than 40% reported significant emotional distress (CES-D ? 16) that warrants clinical attention. Findings showed that while 64% of study participants had future plans regarding who will substitute in their caregiving role if they become incapacitated, only 9% had completed a living will. Three major themes emerged regarding custodial grandmothers' caregiving role which includes: (1) rewards; (2) challenges including feeling overwhelmed and health concerns; and (3) caregiving decisions including conflicts between 'My plan was…/put self on-hold' for grandchildren and difficulty with future planning. These themes highlighted the dynamics of caregiving across time, including current context and the ongoing process of decision-making. Conclusion: Findings suggest that while African-American custodial grandmothers find caregiving rewarding, they face unique challenges in contemplating and developing future plans. Custodial grandmothers think about substitute caregivers for their grandchildren but need assistance communicating a plan focused on their own needs for future care. Culturally sensitive interventions designed to facilitate effective utilization of future plans within this caregiver population are needed.
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Targeting Nucleus DNA with a Cyclometalated Dipyridophenazineruthenium(II) Complex.
J. Med. Chem.
PUBLISHED: 10-23-2014
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Recently, coordinatively saturated and substitutionally inert Ru(II) complexes have been investigated as anticancer agents. Herein a cyclometalated Ru(II) complex, [Ru(bpy)(phpy)(dppz)](+), was found to be rapidly taken up by cancer cells, and nearly 90% of the complex accumulated in the nuclei of cancer cells after a 2 h incubation. The anticancer activity of this complex was screened against a panel of cancer cell lines. Remarkably, it exhibited IC50 values that were an order of magnitude lower than those of cisplatin. This complex also displayed potencies superior to those of cisplatin against 3D tumor spheroids. Further studies revealed that the high DNA binding affinity of [Ru(bpy)(phpy)(dppz)](+) resulted in effective disruption of the binding of transcription factor NF-?B to DNA sequences, thereby inhibiting cellular transcription and leading to irreversible cancer cell apoptosis. Our work provides new insights into understanding the biological interactions and anticancer molecular mechanisms of DNA-specific Ru(II) polypyridyl complexes.
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Compact LED projector design with high uniformity and efficiency.
Appl Opt
PUBLISHED: 10-17-2014
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The aim of this study is to design a compact LED projector that is divided into two systems: an illumination system and an imaging optical system. The illumination system consists of an RGB LED light source with a collimator lens group and a mirror with a color filter and a lens array integrator instead of an integrated rod so as to improve the uniformity of the light intensity. By using a new total internal reflection prism and projection lens, the whole optical engine is smaller in size and has a higher contrast ratio for image quality. The imaging optical system consists of a total of eight lenses (six spherical lenses and two aspherical lenses), for a total length of 52 mm; a tolerance analysis is conducted. Optical simulation software is used for the system analysis in order to determine the efficiency and uniformity of the light intensity. In this design, the uniformity of the screen reaches more than 82%, and the efficiency increases by more than 44%.
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Dual inhibition of topoisomerases I and II? by ruthenium(ii) complexes containing asymmetric tridentate ligands.
Dalton Trans
PUBLISHED: 10-16-2014
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Five novel ruthenium(ii) complexes, [Ru(dtzp)(dppt)](2+) (), [Ru(dtzp)(pti)](2+) (), [Ru(dtzp)(ptn)](2+) (), [Ru(dtzp)(pta)](2+) () and [Ru(dtzp)(ptp)](2+) () (where dtzp = 2,6-di(thiazol-2-yl)pyridine, dppt = 3-(1,10-phenanthroline-2-yl)-5,6-diphenyl-as-triazine), pti = 3-(1,10-phenanthroline-2-yl)-as-triazino-[5,6-f]isatin, ptn = 3-(1,10-phenanthroline-2-yl)-as-triazino[5,6-f]naphthalene, pta = 3-(1,10-phenanthroline-2-yl)-as-triazino[5,6-f]acenaphthylene, and ptp = 3-(1,10-phenanthroline-2-yl)-as-triazino[5,6-f]-phenanthrene), were synthesised and characterised. The structures of complexes were determined by X-ray diffraction. The DNA binding behaviours of the complexes were studied by spectroscopic and viscosity measurements. The results suggested that the Ru(ii) complexes, except for complex , bind to DNA in an intercalative mode. Topoisomerase inhibition and DNA strand passage assay confirmed that Ru(ii) complexes , , and acted as efficient dual inhibitors of topoisomerases I and II?. In vitro cytotoxicity assays indicated that these complexes exhibited anticancer activity against various cancer cell lines. Ruthenium(ii) complexes were confirmed to preferentially accumulate in the nucleus of cancer cells and induced DNA damage. Flow cytometric analysis and AO/EB staining assays indicated that these complexes induced cell apoptosis. With the loss of the mitochondrial membrane potential, the Ru(ii) complexes induce apoptosis via the mitochondrial pathway.
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Growth and Raman spectra of single-crystal trilayer graphene with different stacking orientations.
ACS Nano
PUBLISHED: 10-08-2014
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Understanding the growth mechanism of graphene layers in chemical vapor deposition (CVD) and their corresponding Raman properties is technologically relevant and of importance for the application of graphene in electronic and optoelectronic devices. Here, we report CVD growth of single-crystal trilayer graphene (TLG) grains on Cu and show that lattice defects at the center of each grain persist throughout the growth, indicating that the adlayers share the same nucleation site with the upper layers and these central defects could also act as a carbon pathway for the growth of a new layer. Statistics shows that ABA, 30-30, 30-AB, and AB-30 make up the major stacking orientations in the CVD-grown TLG, with distinctive Raman 2D characteristics. Surprisingly, a high level of lattice defects results whenever a layer with a twist angle of ? = 30° is found in the multiple stacks of graphene layers.
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Layer-dependent optical conductivity in atomic thin WS? by reflection contrast spectroscopy.
ACS Appl Mater Interfaces
PUBLISHED: 09-05-2014
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Optical conductivity, which originates from the interband transition due to electron-phonon interaction, is one of the powerful tools used for studying the electronic states in layered transition metal dichalcogenides (TMDCs). Here, we report for the first time the optical conductivity of WS2, one of the emerging classes of TMDCs, prepared directly on SiO2/Si substrate using reflection contrast spectroscopy. The measured optical conductivity at direct excitonic transition point K of the Brillouin zone for monolayer WS2 shows a value of 0.37 e(2)/?? in the visible range of the energy spectrum. Our results reveal that the optical conductivity of WS2 layers is frequency-dependent and show additional features in the conductivity spectra for bilayer to bulk counterparts, signifying a transition from direct band gap to indirect band gap with the evolution of layer numbers as predicted by our calculations.
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[Construction of Saccharomyces cerevisiae haploid mutant deficient in lanosterol synthase gene].
Yao Xue Xue Bao
PUBLISHED: 08-26-2014
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Lanosterol synthase is encoded by the erg7 gene and catalyzes the cyclization of 2, 3-oxidosqualene, which is a rate-limiting step of the inherent mevalonate (MVA)/ergosterol metabolic pathway in Saccharomyces cerevisiae. The intermediate 2, 3-oxidosqualene is also the precursor of triterpenoids. Therefore, the cyclization of 2, 3-oxidosqualene is the key branch point of ergosterol and triterpenoids biosynthesis. Down-regulation of 2, 3-oxidosqualene metabolic flux to ergosterol in S. cerevisiae may redirect the metabolic flux toward the triterpenoid synthetic pathway reconstructed by the synthetic biology approach. To construct erg7 knockout cassette harboring the loxP-Marker-loxP element, long primers were designed, which were homologous to the sequences of both erg7 ORF and plasmid pUG66. The cassette was transformed into diploid wild strain INVSc1 by LiAc/SS Carrier DNA/PEG method and then erg7 gene haploid deficient mutant was obtained by homologous recombination. The results of semiquantitative PCR and real-time quantitative PCR revealed that erg7 expression level in erg7 gene haploid deficient mutant is one time lower than that in wild strain. The results of TLC and HPLC showed that the ergosterol content in deficient mutant decreased to 42% of that in wild strain.
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Downregulation of microRNA-100 enhances the ICMT-Rac1 signaling and promotes metastasis of hepatocellular carcinoma cells.
Oncotarget
PUBLISHED: 08-20-2014
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Metastasis is responsible for rapid recurrence of hepatocellular carcinoma (HCC) and poor survival of HCC patients. Here we showed that miR-100 downregulation in HCC tissues was significantly associated with venous invasion, advanced TNM stage, tumor nodule without complete capsule, poorer cell differentiation, and shorter recurrence-free survival. Both gain- and loss-of-function studies showed that miR-100 dramatically suppressed the ability of HCC cells to migrate and to invade through Matrigel in vitro. Analyses using mouse orthotopic xenograft model further revealed that xenografts of miR-100-stable-expressing HCC cells displayed a significant reduction in pulmonary metastasis, compared with control group. Subsequent investigations revealed that miR-100 directly inhibited the expression of isoprenylcysteine carboxyl methyltransferase (ICMT) and ras-related C3 botulinum toxin substrate 1 (Rac1) by binding to their 3'-UTRs, and in turn suppressed lamellipodia formation and matrix metallopeptidase 2 (MMP2) activation. Furthermore, knockdown of ICMT and Rac1 phenocopied the anti-metastasis effect of miR-100, whereas overexpression of the constitutively active Rac1 (Q61L) antagonized the function of miR-100. Taken together, miR-100 represses metastasis of HCC cells by abrogating the ICMT-Rac1 signaling. Downregulation of miR-100 contributes to HCC metastasis and the restoration of miR-100 is a potential strategy for cancer therapy.
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Comparison Between Polypyridyl and Cyclometalated Ruthenium(II) Complexes: Anticancer Activities Against 2D and 3D Cancer Models.
Chemistry
PUBLISHED: 08-19-2014
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The aim of this study was to illustrate the dramatically different anticancer activities between coordinatively saturated polypyridyl (1?a-4?a) and cyclometalated (1?b-4?b) ruthenium(II) complexes. The cyclometalated complexes 1?b-4?b function as DNA transcription inhibitors, exhibiting switch-on cytotoxicity against a 2D cancer cell monolayer, whereas the polypyridyl complexes 1?a-4?a are relatively inactive. Moreover, complexes 1?b-4?b exhibit excellent cytotoxicity against 3D multicellular tumor spheroids (MCTSs), which serve as an intermediate model between in vitro 2D cell monolayers and in vivo 3D solid tumors. The hydrophobicity, efficient cell uptake, and nucleus targeting ability, as well as the high DNA binding affinity of complexes 1?b-4?b, likely contribute to their enhanced anticancer activity. We surmise that cyclometalation could be a universal approach to significantly enhance the anticancer activity of substituted polypyridyl Ru(II) complexes. We also suggest that 3D MCTSs may be a more practical platform for anticancer drug screening than 2D cancer monolayer approaches.
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Synthesis, DNA interaction and anticancer activity of copper(II) complexes with 4'-phenyl-2,2':6',2?-terpyridine derivatives.
J. Inorg. Biochem.
PUBLISHED: 08-19-2014
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Three novel copper(II) complexes CuL(1)Cl2 (1) (L(1)=4'-(3-methoxyphenyl)-2,2':6'- 2?-terpyridine), CuL(2)Cl2 (2) (L(2)=4'-(4-methoxyphenyl)-2,2':6'-2?-terpyridine) and CuL(3)Cl2 (3) (L(3)=4'-(3,5-dimethoxyphenyl)-2,2':6'-2?-terpyridine) have been synthesized and characterized. Absorption spectral titration experiments, ethidium bromide displacement assays, and cyclic voltammetric experiments were carried out and the results suggested that these complexes bound to DNA through an intercalative mode. Moreover, these complexes were found to cleave pBR322 DNA efficiently in the presence of glutathione (GSH), and exhibited good anticancer activity against HeLa, Hep-G2 and BEL-7402 cell lines. Nuclear chromatin cleavage was also observed by acridine orange/ethidium bromide (AO/EB) staining assays and comet assays. These results demonstrated that these three Cu(II) complexes caused DNA damage and induced the apoptosis of HeLa cells. Mechanistic investigations revealed the participation of reactive oxygen species which can be trapped by reactive oxygen species (ROS) radical scavengers and ROS sensors.
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Over-expression of testis-specific expressed gene 1 attenuates the proliferation and induces apoptosis of GC-1spg cells.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 08-19-2014
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The effects of over-expression of testis-specific expressed gene 1 (TSEG-1) on the viability and apoptosis of cultured spermatogonial GC-1spg cells were investigated, and the immortal spermatogonial cell line GC-1spg (CRL-2053™) was obtained as the cell model in order to explore the function of TSEG-1. We transfected the eukaryotic vector of TSEG-1, named as pEGFP-TSEG-1 into cultured spermatogonial GC-1spg cells. Over-expression of TSEG-1 inhibited the proliferation of GC-1spg cells, and arrested cell cycle slightly at G0/G1 phase. Transfection of TSEG-1 attenuated the transcript levels of Ki-67, PCNA and cyclin D1. In addition, over-expression of TSEG-1 induced early and late apoptosis, and reduced the mitochondrial membrane potential of GC-1spg cells. Moreover, transfection of TSEG-1 significantly enhanced the ratio of Bax/Bcl-2 and transcript levels of caspase 9, and decreased the expression of Fas and caspase 8 in GC-1spg cells. These results indicated over-expression of TSEG-1 suppresses the proliferation and induces the apoptosis of GC-1spg cells, which establishes a basis for further study on the function of TSEG-1.
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RuNH2@AuNPs as two-photon luminescent probes for thiols in living cells and tissues.
Biomaterials
PUBLISHED: 08-04-2014
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Two-photon luminescent sensors have emerged as promising molecular tools for imaging biomolecules in living systems. Here, we present hybrid gold nanocomposites RuNH2@AuNPs as luminescence off-on probes in response to thiols, which can replace the Ru(II) complexes on the surfaces of the AuNPs to release the luminophore RuNH2. The liberated Ru(II) complexes exhibit strong two-photon luminescence and a large two-photon absorption cross section by using the two-photon excitation wavelength at 800 nm. Furthermore, the probe responses toward thiols with high selectivity and insensitivity to pH over the biologically relevant pH range. This two-photon probe can visualize biological thiols levels in live cells as well as in living mouse tissues at depths of 80-170 ?m by two-photon microscopy.
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Gigahertz flexible graphene transistors for microwave integrated circuits.
ACS Nano
PUBLISHED: 07-29-2014
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Flexible integrated circuits with complex functionalities are the missing link for the active development of wearable electronic devices. Here, we report a scalable approach to fabricate self-aligned graphene microwave transistors for the implementation of flexible low-noise amplifiers and frequency mixers, two fundamental building blocks of a wireless communication receiver. A devised AlOx T-gate structure is used to achieve an appreciable increase of device transconductance and a commensurate reduction of the associated parasitic resistance, thus yielding a remarkable extrinsic cutoff frequency of 32 GHz and a maximum oscillation frequency of 20 GHz; in both cases the operation frequency is an order of magnitude higher than previously reported. The two frequencies work at 22 and 13 GHz even when subjected to a strain of 2.5%. The gigahertz microwave integrated circuits demonstrated here pave the way for applications which require high flexibility and radio frequency operations.
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Gating electron-hole asymmetry in twisted bilayer graphene.
ACS Nano
PUBLISHED: 07-10-2014
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Electron-hole symmetry is one of the unique properties of graphene that is generally absent in most semiconductors because of the different conduction and valence band structures. Here we report on the manipulation of electron-hole symmetry in the low-energy band structure of twisted bilayer graphene, where symmetric saddle points form in the conduction and valence bands as a result of interlayer coupling. By applying a gate voltage to a twisted bilayer with a critical rotation angle, enhanced electron resonance between the two saddle points can be turned on or off, depending on the electron-hole symmetry near the saddle points. The appearance of a 2D(+) peak, a gate-tunable Raman feature found near the critical angle, indicates a reduction of Fermi velocity in the vicinity of the saddle point to/from which electrons are inelastically scattered by phonons in the round trip of the double-resonance process.
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[Role of orphan G protein-coupled receptor 55 in diabetic gastroparesis in mice].
Sheng Li Xue Bao
PUBLISHED: 06-27-2014
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The aim of the present study was to explore the role of orphan G protein-coupled receptor 55 (GPR55) in diabetic gastroparesis (DG). Streptozotocin (STZ) was used to mimic the DG model, and the body weight and blood glucose concentration were tested 4 weeks after STZ injection (i.p.). Electrogastrogram and phenolsulfonphthalein test were used for detecting gastric emptying. Motilin (MTL), gastrin (GAS), vasoactive intestinal peptide (VIP), and somatostatin (SS) levels in plasma were determined using radioimmunology. Real-time PCR and Western blot were applied to identify the expression of GPR55 in gastric tissue, and immunohistochemistry was used to detect the distribution. The effect of lysophosphatidylinositol (LPI), an agonist of GPR55, was observed. STZ mice showed increased blood glucose concentration, lower body weight, decreased amplitude of slow wave, and delayed gastric emptying. LPI antagonized these effects of STZ. Compared to the control group, STZ caused significant decreases of MTL and GAS levels (P < 0.01), as well as increases of SS and VIP levels (P < 0.01). The changes of these hormones induced by STZ were counteracted when using LPI. GPR55 located in mice stomach, and it was up-regulated in DG. Although LPI showed no effects on the distribution and expression of GPR55 in normal mice, it could inhibit STZ-induced GPR55 up-regulation. These results suggest GPR55 is involved in the regulation of gastric movement of DG, and may serve as a new target of DG treatment. LPI, an agonist of GPR55, can protect against STZ-induced DG, and the mechanism may involve the change of GPR55 expression and modification of gastrointestinal movement regulating hormones.
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A novel method for rapid determination of total solid content in viscous liquids by multiple headspace extraction gas chromatography.
J Chromatogr A
PUBLISHED: 06-03-2014
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This work demonstrates a novel method for rapid determination of total solid content in viscous liquid (polymer-enriched) samples. The method is based multiple headspace extraction gas chromatography (MHE-GC) on a headspace vial at a temperature above boiling point of water. Thus, the trend of water loss from the tested liquid due to evaporation can be followed. With the limited MHE-GC testing (e.g., 5 extractions) and a one-point calibration procedure (i.e., recording the weight difference before and after analysis), the total amount of water in the sample can be determined, from which the total solid contents in the liquid can be calculated. A number of black liquors were analyzed by the new method which yielded results that closely matched those of the reference method; i.e., the results of these two methods differed by no more than 2.3%. Compared with the reference method, the MHE-GC method is much simpler and more practical. Therefore, it is suitable for the rapid determination of the solid content in many polymer-containing liquid samples.
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Measuring gene expression in single bacterial cells: recent advances in methods and micro-devices.
Crit. Rev. Biotechnol.
PUBLISHED: 04-09-2014
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Abstract Populations of bacterial cells that grow under the same conditions and/or environments are often considered to be uniform and thus can be described by ensemble average values of their physiologic, phenotypic, genotypic or other parameters. However, recent evidence suggests that cell-to-cell differences at the gene expression level could be an order of magnitude greater than previously thought even for isogenic bacterial populations. Such gene expression or transcriptional-level heterogeneity determines not only the fate of individual bacterial cells in a population but could also affect the ultimate fate of the population itself. Although techniques for single-cell gene expression measurement in eukaryotic cells have been successfully implemented for a decade or so, they have only recently become available for single bacterial cells. This is due to the difficulty of efficient lysis of most bacterial cells, as well as short half-life time (low stability) of bacterial mRNA. In this article, we review the recent progress and challenges associated with analyzing gene expression levels in single bacterial cells using various semi-quantitative and quantitative methods. In addition, a review of the recent progress in applying microfluidic devices to isolate single bacterial cells for gene expression analysis is also included.
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Novel ruthenium(II) polypyridyl complexes as G-quadruplex stabilisers and telomerase inhibitors.
Dalton Trans
PUBLISHED: 04-04-2014
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Two novel ruthenium polypyridyl complexes, Ru[(bpy)2(pedppz)](2+) (1) and Ru[(bpy)2(pemitatp)](2+) (2) (bpy = 2'2-bipyridine, pdeppz = 10-(2-(piperidin-1-yl)ethoxy)dipyrido[3,2-a:2',3'-c]phenazine, pemitatp = 5-methoxy-1-(2-(piperidin-1-yl)ethyl)-isatino[1,2-b]-1,4,8,9-tetraazatriphenylene), bearing large planar ?-delocalized aromatic systems with flexible chains have been synthesised and characterised. As expected, these complexes show inhibition towards telomerase by inducing and stabilising the G-quadruplex structure.
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Characterization of lymph node metastasis and its clinical significance in the surgical treatment of gastric cancer.
Mol Clin Oncol
PUBLISHED: 04-02-2014
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This study aimed to characterize lymph node metastasis and determine its clinical significance in the surgical treatment of gastric cancer. The medical charts of 920 gastric cancer patients who underwent radical surgical resection between March, 2010 and March, 2013, were retrospectively reviewed and statistically analyzed. Lymphatic metastasis was observed in 69.6% of the patients (640/920). The frequency of lymph node metastasis in patients with early-stage gastric cancer was 21.4% (18/84). Lymph node metastasis was observed in all the patients with stage IIIC-IV gastric cancer. The incidence of lymph node metastasis was higher among patients with tumors >7 cm in size. The most frequently affected lymph nodes in patients with proximal, central and distal gastric cancer were station no. 1 (34.2%), no. 3 (33.8%) and no. 6 (34.3%) lymph nodes, respectively. The frequency of lymph node metastasis in patients with Borrmann type IV cancer was significantly higher compared to that in patients with other Borrmann type cancers. Our study further demonstrated that lymphatic metastasis is closely correlated with TNM stage, location, depth of invasion and size of gastric tumors. Therefore, we recommend that a sufficient number of lymph nodes be examined from each patient to determine the extent of lymph node dissection based on Borrmann type, location, size, depth of invasion and histology of the cancer.
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Comparision of modified and conventional delta-shaped gastroduodenostomy in totally laparoscopic surgery.
World J. Gastroenterol.
PUBLISHED: 03-26-2014
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To evaluate the safety and feasibility of a modified delta-shaped gastroduodenostomy (DSG) in totally laparoscopic distal gastrectomy (TLDG).
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Betatrophin provides a new insight into diabetes treatment and lipid metabolism (Review).
Biomed Rep
PUBLISHED: 03-21-2014
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Replenishing the insulin-producing ?-cell mass is considered to be a potential cure for diabetes. A recent study identified a secreted protein, known as betatrophin, which potently induces pancreatic ?-cell proliferation. Notably, a number of studies reportedly identified betatrophin, which is also known as lipasin, atypical angiopoietin-like 8 and refeeding-induced fat and liver protein, and considered to be a novel regulator in lipid metabolism according to the studies. The identification of betatrophin was considered to create novel opportunities for potential diabetes therapy. In the present study, the current knowledge of betatrophin is reviewed, with regards to its character and function in lipid homeostasis and pancreatic ?-cell proliferation.
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Direct growth of self-crystallized graphene and graphite nanoballs with Ni vapor-assisted growth: from controllable growth to material characterization.
Sci Rep
PUBLISHED: 03-17-2014
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A directly self-crystallized graphene layer with transfer-free process on arbitrary insulator by Ni vapor-assisted growth at growth temperatures between 950 to 1100 °C via conventional chemical vapor deposition (CVD) system was developed and demonstrated. Domain sizes of graphene were confirmed by Raman spectra from ~12 nm at growth temperature of 1000 °C to ~32 nm at growth temperature of 1100 °C, respectively. Furthermore, the thickness of the graphene is controllable, depending on deposition time and growth temperature. By increasing growth pressure, the growth of graphite nano-balls was preferred rather than graphene growth. The detailed formation mechanisms of graphene and graphite nanoballs were proposed and investigated in detail. Optical and electrical properties of graphene layer were measured. The direct growth of the carbon-based materials with free of the transfer process provides a promising application at nanoelectronics.
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Is national socioeconomic status related to prevalence of irritable bowel syndrome?
J. Gastroenterol. Hepatol.
PUBLISHED: 03-09-2014
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There are a multitude of cross-sectional surveys that provide the prevalence of irritable bowel syndrome (IBS) in the community. However, the data regarding the influence of socioeconomic status on prevalence of IBS were sparse. This study is to investigate the possible relation between human development and prevalence of IBS, at national level.
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Laparoscopic spleen-preserving no. 10 lymph node dissection for advanced proximal gastric cancer using a left approach.
Ann. Surg. Oncol.
PUBLISHED: 03-04-2014
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We developed a novel procedure for spleen-preserving No. 10 lymph node (LN) dissection, which is difficult and advocates for patients with advanced proximal gastric cancer, except those with direct tumor extension to the spleen or definite LN metastasis at the splenic hilum.
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Role of endoplasmic reticulum stress in the pathogenesis of nonalcoholic fatty liver disease.
World J. Gastroenterol.
PUBLISHED: 03-04-2014
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Nonalcoholic fatty liver disease (NAFLD) has emerged as a common public health problem in recent decades. However, the underlying mechanisms leading to the development of NAFLD are not fully understood. The endoplasmic reticulum (ER) stress response has recently been proposed to play a crucial role in both the development of steatosis and progression to nonalcoholic steatohepatitis. ER stress is activated to regulate protein synthesis and restore homeostatic equilibrium when the cell is stressed due to the accumulation of unfolded or misfolded proteins. However, delayed or insufficient responses to ER stress may turn physiological mechanisms into pathological consequences, including fat accumulation, insulin resistance, inflammation, and apoptosis, all of which play important roles in the pathogenesis of NAFLD. Therefore, understanding the role of ER stress in the pathogenesis of NAFLD has become a topic of intense investigation. This review highlights the recent findings linking ER stress signaling pathways to the pathogenesis of NAFLD.
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National HIV/AIDS mortality, prevalence, and incidence rates are associated with the Human Development Index.
Am J Infect Control
PUBLISHED: 03-01-2014
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HIV/AIDS is a worldwide threat to human health with mortality, prevalence, and incidence rates varying widely. We evaluated the association between the global HIV/AIDS epidemic and national socioeconomic development.
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Effects of pentoxifylline on nonalcoholic fatty liver disease: a meta-analysis.
World J. Gastroenterol.
PUBLISHED: 02-28-2014
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To evaluate the effects of pentoxifylline therapy in patients with nonalcoholic fatty liver disease (NAFLD).
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Roles of heat shock factor 1 in neuronal response to fetal environmental risks and its relevance to brain disorders.
Neuron
PUBLISHED: 02-20-2014
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Prenatal exposure of the developing brain to various environmental challenges increases susceptibility to late onset of neuropsychiatric dysfunction; still, the underlying mechanisms remain obscure. Here we show that exposure of embryos to a variety of environmental factors such as alcohol, methylmercury, and maternal seizure activates HSF1 in cerebral cortical cells. Furthermore, Hsf1 deficiency in the mouse cortex exposed in utero to subthreshold levels of these challenges causes structural abnormalities and increases seizure susceptibility after birth. In addition, we found that human neural progenitor cells differentiated from induced pluripotent stem cells derived from schizophrenia patients show higher variability in the levels of HSF1 activation induced by environmental challenges compared to controls. We propose that HSF1 plays a crucial role in the response of brain cells to prenatal environmental insults and may be a key component in the pathogenesis of late-onset neuropsychiatric disorders.
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Huang's three-step maneuver for laparoscopic spleen-preserving No. 10 lymph node dissection for advanced proximal gastric cancer.
Chin. J. Cancer Res.
PUBLISHED: 02-17-2014
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Due to the complexity of the splenic hilar vessels, their anatomical variation and the narrow and deep space, as well as the bleeding-prone splenic parenchyma and the difficulty to manage splenic or vascular bleeding at the splenic hilum,the procedure remains challenging and technically demanding procedure for the performance of laparoscopic pancreas- and spleen-preserving splenic hilar lymph nodes dissection. Based on our experiences, we gradually explored a set of procedural operation steps called "Huang's three-step maneuver". In this paper, we not only provide the concrete operation steps for the surgeon, but we also provide our recommended technique of pulling and exposure for assistants. This new maneuver simplifies the complicated procedure and improves the efficiency of laparoscopic spleen-preserving splenic hilar lymphadenectomy, making it easier to master and allowing for its widespread adoption.
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Increasing the sensitivity of headspace analysis of low volatility solutes through water removal by hydrate formation.
J Chromatogr A
PUBLISHED: 02-07-2014
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This paper reports on the development of a new headspace analytical technique that is based on water removal by hydrate formation (WRHF). By adding anhydrous salt, the liquid water in an aqueous sample will be removed leaving behind volatile analytes that are fully vaporized at temperatures well below their boiling points. With WRHF, the amount of sample in the headspace can be significantly increased, thereby dramatically improving the detection sensitivity. The technique reduces the risk of possible column damage in gas chromatography (GC) systems. The technique was applied to the determination of phenol at different stages of a coking wastewater treatment plant. The results showed that up to mL-levels of sample solution can be used in WRHF HS-GC analysis when 5g of CaCl2 were used as the anhydrous salt. The detection sensitivity for phenol content was 500 times greater than that in earlier HS-GC work that did not incorporate hydrate formation. The proposed WRHF headspace analysis technique is simple and practical, making it a useful tool for quantifying low concentrations of volatile analytes in aqueous samples.
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Transforaminal percutaneous endoscopic surgery for far lateral lumbar intervertebral disk herniation.
Orthopedics
PUBLISHED: 01-30-2014
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Far lateral lumbar intervertebral disk herniation (FLLIDH) most commonly occurs far lateral to the intervertebral facet at L3-L4 and L4-L5 and accounts for 3.8% of all lumbar disk herniations. Traditional surgery for FLLIDH involves massive surgical trauma, damage to the spinal structure, and instability of the lumbar spine. The goals of this study were to perform a systematic review of the literature and investigate the clinical outcomes of transforaminal percutaneous endoscopic surgery in the treatment of FLLIDH. Between October 2010 and May 2012, fifteen patients diagnosed with FLLIDH underwent transforaminal percutaneous endoscopic surgery at the authors' institution to remove the herniated disk and release the nerve root. Pain was measured pre- and postoperatively with a visual analog pain scale (VAS), and postoperative outcomes were evaluated using MacNab's criteria. A PubMed database search was conducted for the systematic review. Median operative time was 100 minutes (range, 80-140 minutes). Median volume of intraoperative blood loss was 20 mL (range, 10-50 mL). Patients were followed postoperatively for a median of 6 months (range, 1-12 months). MacNab's criteria rated 12 (80.0%) surgical outcomes as excellent, 2 (13.3%) as good, and 1 (6.7%) as fair. The systematic review included 14 studies. Transforaminal percutaneous endoscopic surgery appears to be a safe and effective minimally invasive procedure for treating FLLIDH. However, as demand for this type of surgery increases, the possibility of intraoperative aggravated leg pain and compression injury of the ganglion must be considered.
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Prognostic analysis of gastric gastrointestinal stromal tumor with synchronous gastric cancer.
World J Surg Oncol
PUBLISHED: 01-18-2014
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Many patients with gastric gastrointestinal stromal tumor (GIST) and synchronous gastric cancer have been described, most in single case studies. We retrospectively investigated the clinicopathologic features and prognostic effects of gastric GIST in patients with synchronous gastric cancer.
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Survival and surgical outcomes of cardiac cancer of the remnant stomach in comparison with primary cardiac cancer.
World J Surg Oncol
PUBLISHED: 01-18-2014
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Although cardiac cancer of the remnant stomach and primary cardiac cancer both occur in the same position, their clinical characteristics and outcomes have not been compared previously. The objective of this study was designed to evaluate the prognosis of cardiac cancer of the remnant stomach in comparison with primary cardiac cancer.
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Association between serum alpha-fetoprotein levels and fatty liver disease: a cross-sectional study.
World J. Gastroenterol.
PUBLISHED: 01-14-2014
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To investigate the association between serum alpha-fetoprotein (AFP) levels and fatty liver disease (FLD) in a Chinese population.
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Determination of maximal amount of minor gases adsorbed in a shale sample by headspace gas chromatography.
J Chromatogr A
PUBLISHED: 01-14-2014
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In this paper, we present a novel method for determining the maximal amount of ethane, a minor gas species, adsorbed in a shale sample. The method is based on the time-dependent release of ethane from shale samples measured by headspace gas chromatography (HS-GC). The study includes a mathematical model for fitting the experimental data, calculating the maximal amount gas adsorbed, and predicting results at other temperatures. The method is a more efficient alternative to the isothermal adsorption method that is in widespread use today.
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Association of caveolin-3 and cholecystokinin A receptor with cholesterol gallstone disease in mice.
World J. Gastroenterol.
PUBLISHED: 01-13-2014
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To investigate the role of caveolin-3 (CAV3) and cholecystokinin A receptor (CCKAR) in cholesterol gallstone disease (CGD).
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In situ observation of step-edge in-plane growth of graphene in a STEM.
Nat Commun
PUBLISHED: 01-13-2014
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It is extremely difficult to control the growth orientation of the graphene layer in comparison to Si or III-V semiconductors. Here we report a direct observation of graphene growth and domain boundary formation in a scanning transmission electron microscope, with residual hydrocarbon in the microscope chamber being used as the carbon source for in-plane graphene growth at the step-edge of bilayer graphene substrate. We show that the orientation of the growth is strongly influenced by the step-edge structure and areas grown from a reconstructed 5-7 edge are rotated by 30° with respect to the mother layer. Furthermore, single heteroatoms like Si may act as catalytic active sites for the step-edge growth. The findings provide an insight into the mechanism of graphene growth and defect reconstruction that can be used to tailor carbon nanostructures with desired properties.
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Dinuclear ruthenium(II) polypyridyl complexes as single and two-photon luminescence cellular imaging probes.
Chem. Commun. (Camb.)
PUBLISHED: 01-13-2014
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A new series of dinuclear ruthenium(II) polypyridyl complexes, which possess larger ?-conjugated systems, good water solubility and pH resistance, and high photostability, were developed to act as single and two-photon luminescence cellular imaging probes.
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Laparoscopic spleen-preserving splenic hilar lymphadenectomy in 108 consecutive patients with upper gastric cancer.
World J. Gastroenterol.
PUBLISHED: 01-08-2014
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To evaluate the feasibility and short-term efficacy of laparoscopic spleen-preserving splenic hilar (No. 10) lymphadenectomy to treat advanced upper gastric cancer (AUGC).
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Role of 3DCT in laparoscopic total gastrectomy with spleen-preserving splenic lymph node dissection.
World J. Gastroenterol.
PUBLISHED: 01-08-2014
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To investigate whether computed tomography with 3D imaging (3DCT) can reduce the risks associated with laparoscopic surgery.
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Is tumor size a predictor of preoperative N staging in T2-T4a stage advanced gastric cancer?
Surg Oncol
PUBLISHED: 01-07-2014
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The aim of this study was to assess the relationship between tumor size and preoperative N staging in patients with T2-T4a stage advanced gastric cancer.
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Traditional Chinese medicine for idiopathic precocious puberty: A hospital-based retrospective observational study.
Complement Ther Med
PUBLISHED: 01-06-2014
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To characterize the application of traditional Chinese medicine (TCM) among children with idiopathic precocious puberty (IPP).
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Mesohepatectomy for the treatment of patients with centrally located hepatocellular carcinoma.
Mol Clin Oncol
PUBLISHED: 01-04-2014
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Mesohepatectomy is considered a feasible option for patients with centrally located hepatocellular carcinoma (HCC). However, mesohepatectomy is a technically demanding and less frequently used procedure. In this study, we summarized the surgical experience and evaluated the clinical outcomes of mesohepatectomy in 24 patients with centrally located HCC. Of these patients, 9 were treated with hepatectomy of Couinaud's segments IV, V and VIII with concurrent cholecystectomy; 8 underwent resection of segments IVb, V and VIII, including 7 patients who also received a cholecystectomy; 4 underwent hepatectomy of segments IVa, V and VIII; and 3 patients were treated with hepatectomy of segments I, IV, V and VIII, with concurrent cholecystectomy. The Pringle maneuver was used on 17 patients during hepatectomy. Total hepatic vascular exclusion (HVE) was performed on 3 patients and HVE was not used on 4 patients. The average mesohepatectomy operative time was 238 min and the average intraoperative blood loss was 480 ml (200-2,200 ml). There was no intraoperative mortality and the postoperative morbidity rate was 25% (6/24). The 1- and 3-year overall survival rates were 76 and 46%, respectively. Therefore, mesohepatectomy is a safe and effective surgical procedure for the treatment of centrally located HCC and HVE during mesohepatectomy for centrally located HCC is crucial to the success of the operation and postoperative patient recovery.
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Scalable graphite/copper bishell composite for high-performance interconnects.
ACS Nano
PUBLISHED: 01-02-2014
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We present the fabrication and characterizations of novel electrical interconnect test lines made of a Cu/graphite bishell composite with the graphite cap layer grown by electron cyclotron resonance chemical vapor deposition. Through this technique, conformal multilayer graphene can be formed on the predeposited Cu interconnects under CMOS-friendly conditions. The low-temperature (400 °C) deposition also renders the process unlimitedly scalable. The graphite layer can boost the current-carrying capacity of the composite structure to 10(8) A/cm(2), more than an order of magnitude higher than that of bare metal lines, and reduces resistivity of fine test lines by ?10%. Raman measurements reveal that physical breakdown occurs at ?680-720 °C. Modeling the current vs voltage curves up to breakdown shows that the maximum current density of the composites is limited by self-heating of the graphite, suggesting the strong roles of phonon scattering at high fields and highlighting the significance of a metal counterpart for enhanced thermal dissipation.
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Strong light coupling effect for a glancing-deposited silver nanorod array in the Kretschmann configuration.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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In this work, three slanted silver nanorod arrays (NRAs) with different thicknesses are fabricated using the glancing angle deposition method. Each silver NRA in the Kretschmann configuration is arranged to form a prism/NRA/air system. Attenuated total reflection occurs over the visible wavelengths and wide incident angles of both s- and p-polarization states. The extinctance is inversely proportional to the thickness of the Ag NRA. The thinnest NRA, with a thickness of 169 nm, exhibits strong extinctance of more than 80% over the visible wavelengths. The associated forward scatterings from the three NRAs are measured and compared under illumination with a laser beam with a wavelength of 632.8 nm.
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miR-183 inhibits invasion of gastric cancer by targeting Ezrin.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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miR-183, a member of an evolutionarily conserved miRNA cluster (miR-96, miR-182, and miR-183), has been demonstrated to act as both a tumor suppressor and oncogene in various type of human cancer. However, the biological role of miR-183 in gastric cancer (GC) still remains unclear. In the present study, miR-183 expression was significantly decreased in gastric cancer tissues compared with its' adjacent normal tissues, and down-regulation of miR-183 was significantly associated with lymph node metastasis and pathological TNM stage. Furthermore, Erzin, which was reported to be up-regulated in gastric cancer, was identified as an efficient target of miR-183. Overexpression of miR-183 markedly suppressed cells invasion by downregulation of Ezrin expression. However, miR-183 expression didn't affect cells proliferation and cell cycle distribution of GC. In conclusion, our study demonstrated that miR-183 acts as a tumor suppressor in GC, partially at least via regulation of Ezrin. Therefore, miR-183 may be a potential target for the treatment of gastric cancer.
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A 346 case analysis for laparoscopic spleen-preserving no.10 lymph node dissection for proximal gastric cancer: a single center study.
PLoS ONE
PUBLISHED: 01-01-2014
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This study was designed to formulate a model that efficiently predicts splenic hilar lymph node metastasis (SHLNM) in patients with proximal gastric cancer and to assess indications for laparoscopic spleen-preserving no.10 lymph node dissection (LSPNo.10LND) based on this model.
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Does tumor size improve the accuracy of prognostic predictions in node-negative gastric cancer (pT1-4aN0M0 stage)?
PLoS ONE
PUBLISHED: 01-01-2014
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The prognostic importance of tumor size in gastric cancer is unclear. This study investigated whether the inclusion of tumor size could improve prognostic accuracy in node-negative gastric cancer.
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Lipotoxic effect of p21 on free fatty acid-induced steatosis in L02 cells.
PLoS ONE
PUBLISHED: 01-01-2014
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Nonalcoholic fatty liver disease (NAFLD) is increasingly regarded as a hepatic manifestation of metabolic syndrome. Though with high prevalence, the mechanism is poorly understood. This study aimed to investigate the effects of p21 on free fatty acid (FFA)-induced steatosis in L02 cells. We therefore analyzed the L02 cells with MG132 and siRNA treatment for different expression of p21 related to lipid accumulation and lipotoxicity. Cellular total lipid was stained by Oil Red O, while triglyceride content, cytotoxicity assays, lipid peroxidation markers and anti-oxidation levels were measured by enzymatic kits. Treatment with 1 mM FFA for 48 hr induced magnificent intracellular lipid accumulation and increased oxidative stress in p21 overload L02 cells compared to that in p21 knockdown L02 cells. By increasing oxidative stress and peroxidation, p21 accelerates FFA-induced lipotoxic effect in L02 cells and might provide information about potentially new targets for drug development and treatments of NAFLD.
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Laparoscopic spleen-preserving splenic hilar lymphadenectomy performed by following the perigastric fascias and the intrafascial space for advanced upper-third gastric cancer.
PLoS ONE
PUBLISHED: 01-01-2014
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Laparoscopic spleen-preserving Splenic hilar lymphadenectomy (LSPL) is required in laparoscopy-assisted total gastrectomy for advanced proximal gastric cancer. However, it is considerably difficult and risk in clinical practice. Thus, we explore the application of LSPL performed by following the perigastric fascias and the intrafascial space in D2 radical gastrectomy for advanced upper-third gastric cancer.
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[A triple-wavelength visible spectroscopic method for determination of iron content in lignocellulosic materials].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 12-28-2013
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The present paper described a triple-wavelength visible spectroscopic method for the determination of iron content in lignocellulosic materials. After the sample was pretreated with acidic hydrolysis method under selected conditions, the color agent, 1, 10-phenanthroline monohydrate, was added in the filtrate and then measured by a triple-wavelength spectroscopic method at wavelengths of 416, 510 and 700 nm, from which the iron contents of the sample can be calculated. The results showed that this method can efficiently deduct the influences of acidic soluble lignin and furfural compounds generated during the sample pretreatment and baseline drift caused by the tiny particles in the filtrates. It not only has a good measurement precision but also is accurate, in which the relative differences of the results obtained by the present method and ICP-OES method is less than 5%. The method is simple and practical, and suitable for industrial applications.
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Upregulation of caveolin-1 and SR-B1 in mice with non-alcoholic fatty liver disease.
HBPD INT
PUBLISHED: 12-11-2013
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Non-alcoholic fatty liver disease (NAFLD) is one of the most frequent causes of liver diseases, with markedly increased prevalence. However, its mechanisms are not clear. The present study was undertaken to illustrate the role of caveolin-1 (cav1) and the scavenger receptor class B type 1 (SR-B1) in NAFLD.
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[Expression tumor stem cell surface marker CD44 in gastric cancer and its significance].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 11-27-2013
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To investigate the expression of tumor stem cell surface marker CD44 in gastric cancer and its clinical value.
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Mitochondria-specific phosphorescent imaging and tracking in living cells with an AIPE-active iridium(III) complex.
Chem. Commun. (Camb.)
PUBLISHED: 10-22-2013
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An AIPE-active iridium(III) complex was found to possess high specificity for mitochondria, superior photostability, low cytotoxicity, and high resistance to the loss of mitochondrial membrane potential. Thus, this complex can be used for mitochondrial imaging and tracking in living cells.
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A fast method for spine localization in x-ray images.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 10-11-2013
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Detection of spines in medical images are important tasks in medical applications. These tasks are relatively easy for CT/MR images because the bones are easily distinguishable from other tissues. However, they are difficult for x-ray images due to bone and soft tissue overlapping. This paper illustrates a method for detecting the medial axis of spine in x-ray images. Given an initial point on the spine in the x-ray image manually or automatically, the method iteratively searches for good feature points on the spine to locate the medial axis. As a result, the effort of determining the relevant medical information, such as Cobbs angle, can be minimized. The proposed method is fast and efficient. In average it took less than 1 second for localizing the spine on a 3000×1000 gray scale x-ray image.
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An analysis-synthesis approach for neurosphere modelisation under phase-contrast microscopy.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 10-11-2013
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The study of stem cells is one of the most important biomedical research. Understanding their development could allow multiple applications in regenerative medicine. For this purpose, automated solutions for the observation of stem cell development process are needed. This study introduces an on-line analysis method for the modelling of neurosphere evolution during the early time of their development under phase contrast microscopy. From the corresponding phase contrast time-lapse sequences, we extract information from the neurosphere using a combination of phase contrast physics deconvolution and curve detection for locate the cells inside the neurosphere. Then, based on prior biological knowledge, we generate possible and optimal 3-dimensional configuration using 2D to 3D registration methods and evolutionary optimisation algorithm.
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A fluorescent colorimetric pH sensor and the influences of matrices on sensing performances.
Sens Actuators B Chem
PUBLISHED: 10-01-2013
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A fluorescent colorimetric pH sensor was developed by a polymerization of a monomeric fluorescein based green emitter (SM1) with a monomeric 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran derived red emitter (SM2) in poly(2-hydroxyethyl methacrylate)-co-polyacrylamide (PHEMA-co-PAM) matrices. Polymerized SM1 (PSM1) in the polymer matrices showed bright emissions at basic conditions and weak emissions at acidic conditions. Polymerized SM2 (PSM2) in the polymer matrices exhibited a vastly different response when compared to PSM1. The emissions of PSM2 are stronger under acidic conditions than those under basic conditions. When SM1 and SM2 were polymerized in the same polymer matrix, a dual emission sensor acting as a ratiometric pH sensor (PSM1,2) was successfully developed. Because the PSM1 and PSM2 exhibited different pH responses and separated emission windows, the changes in the emission colors were clearly observed in their dual color sensor of PSM1,2, which changed emission colors dramatically from green at pH 7 to red at pH 4, which was detected visually and/or by using a color camera under an excitation of 488 nm. In addition to the development of the dual color ratiometric pH sensor, we also studied the effects of different matrix compositions, crosslinkers, and charges on the reporting capabilities of the sensors (sensitivity and pK a).
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A new headspace gas chromatographic method for the determination of methanol content in paper materials used for food and drink packaging.
J. Agric. Food Chem.
PUBLISHED: 09-19-2013
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This study reports on a method for determination of methanol in paper products by headspace gas chromatography (HS-GC). The method is based on the hydrolysis of the pulp or paper matrix, using a phosphoric acid solution (42.5%) as the medium at 120 °C in 5 h (excluding air contact) in order to release matrix-entrapped methanol, which is then determined by HS-GC. Data show that, under the given conditions of hydrolysis, no methanol was formed from the methoxyl groups in the material. Reproducibility tests of the method generated a relative standard deviation of <3.5%, with recovery in the range of 93.4-102%. The present method is reliable, accurate, and suitable for use in batch testing of the methanol content in paper-related materials. The method can play an important role in addressing food safety concerns that may be raised regarding the use of paper materials in food and beverage packaging.
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Mitochondria are the primary target in the induction of apoptosis by chiral ruthenium(II) polypyridyl complexes in cancer cells.
J. Biol. Inorg. Chem.
PUBLISHED: 09-11-2013
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A series of novel chiral ruthenium(II) polypyridyl complexes (?-Ru1, ?-Ru1, ?-Ru2, ?-Ru2, ?-Ru3, ?-Ru3) were synthesized and evaluated to determine their antiproliferative activities. Colocalization, inductively coupled plasma mass spectrometry, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay studies showed that these ruthenium(II) complexes accumulated preferentially in the mitochondria and exhibited cytotoxicity against various cancer cells in vitro. The complex ?-Ru1 is of particular interest because it was found to have half-maximal inhibitory concentrations comparable to those of cisplatin and better activity than cisplatin against a cisplatin-resistant cell line, A549-CP/R. ?-Ru1 induced alterations in the mitochondrial membrane potential and triggered intrinsic mitochondria-mediated apoptosis in HeLa cells, which involved the regulation of Bcl-2 family members and the activation of caspases. Taken together, these data suggest that ?-Ru1 may be a novel mitochondria-targeting anticancer agent.
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A novel method for the determination of black liquor viscosity by multiple headspace extraction gas chromatography.
J Chromatogr A
PUBLISHED: 09-10-2013
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This work demonstrates a novel method for the determination of viscosity in the concentrated black liquors from pulp mill recovery process. The method is based on the kinetic release of methanol (a vapor tracer) to the headspace in a sample closed vial by a multiple headspace extraction gas chromatographic technique. Both theoretical and empirical models were proposed for establishing the correlation with the reference method. The results showed that the correlation using either of the models is excellent for the tested black liquor samples (at 110°C). The presented method is simple and practical and can be a valuable tool for black liquor viscosity related research and applications.
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Comparison of intratympanic steroid injection, hyperbaric oxygen and combination therapy in refractory sudden sensorineural hearing loss.
Otol. Neurotol.
PUBLISHED: 09-06-2013
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The objective of this study was to compare the efficacy of intratympanic steroid injection (ITS), hyperbaric oxygen (HBO), and combination therapy as salvage treatment in patients with sudden sensorineural hearing loss (SSNHL) after failure of systemic therapy.
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Role of endogenous cannabinoid system in the gut.
Sheng Li Xue Bao
PUBLISHED: 08-22-2013
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The plant Cannabis has been used in clinic for centuries, and has been known to be beneficial in a variety of gastrointestinal diseases, such as emesis, diarrhea, inflammatory bowel disease and intestinal pain. In this text, well review the components of the endogenous cannabinoid system as well as its role in the regulation of gastrointestinal activities, thus providing relative information for further study. Moreover, modulation of the endogenous cannabinoid system in gastrointestinal tract may provide a useful therapeutic target for gastrointestinal disorders.
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A safe anastomotic technique of using the transorally inserted anvil (OrVil™) in Roux-en-Y reconstruction after laparoscopy-assisted total gastrectomy for proximal malignant tumors of the stomach.
World J Surg Oncol
PUBLISHED: 08-14-2013
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To explore the safety and feasibility of the transorally inserted anvil (OrVil™) in laparoscopy-assisted total gastrectomy for gastric cancer.
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Learning curve of laparoscopy spleen-preserving splenic hilar lymph node dissection for advanced upper gastric cancer.
Hepatogastroenterology
PUBLISHED: 08-09-2013
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To investigate the learning curve of laparoscopy spleen-preserving splenic hilar lymph node dissection for advanced upper gastric cancer (AUGC).
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Phosphorescent iridium(III) complexes as multicolor probes for specific mitochondrial imaging and tracking.
Biomaterials
PUBLISHED: 08-08-2013
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In the present study, four phosphorescent iridium(III) complexes [Ir(C-N)2(PhenSe)](+) (Ir1-Ir4, in which C-N = 2-(2,4-difluorophenyl)pyridine (dfppy), dibenzo[f,h]quinoxaline (dbq), 2-phenylquinoline (2-pq) and 2-phenylpyridine (ppy), PhenSe = 1,10-phenanthrolineselenazole) with tunable emission colors were developed to image mitochondria and track the dynamics of the mitochondrial morphology. In comparison with commercially available mitochondrial trackers, Ir1-Ir4 possess high specificity to mitochondria in live and fixed cells without requiring prior membrane permeabilization or the replacement of the culture medium. Due to the high resistance of Ir1-Ir4 to the loss of mitochondrial membrane potential as well as the appreciable tolerance to environmental changes, these complexes are applicable for the imaging and tracking of the mitochondrial morphological changes over long periods of time. In addition, Ir2-Ir4 exhibited superior photostability compared to the commercially available mitochondrial trackers. These colorful iridium(III) complexes may contribute to the future development of staining agents for organelle-selective imaging in living cells.
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Detection of receiver location and migration after cochlear implantation using 3D rendering of computed tomography.
Otol. Neurotol.
PUBLISHED: 08-08-2013
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The purpose of this study was to objectively evaluate the position and migration of the cochlear implant receiver and ball electrode using 3-dimensional (3D) rendering of computed tomography.
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Activation of C-H bonds in nitrones leads to iridium hydrides with antitumor activity.
J. Med. Chem.
PUBLISHED: 08-07-2013
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We report the design and synthesis of a series of new cyclometalated iridium hydrides derived from the C-H bond activation of aromatic nitrones and the biological evaluation of these iridium hydrides as antitumor agents. The nitrone ligands are based on the structure of a popular antioxidant, ?-phenyl-N-tert-butylnitrone (PBN). Compared to cisplatin, the iridium hydrides exhibit excellent antitumor activity on HepG2 cells. The metal-coordinated compound with the most potent anticancer activity, 2f, was selected for further analysis because of its ability to induce apoptosis and interact with DNA. During in vitro studies and in vivo efficacy analysis with tumor xenograft models in Institute of Cancer Research (ICR) mice, complex 2f exhibited antitumor activity that was markedly superior to that of cisplatin. Our results suggest, for the first time, that metal hydrides could be a new type of metal-based antitumor agent.
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A Dinuclear Ruthenium(II) Complex as a One- and Two-Photon Luminescent Probe for Biological Cu(2+) Detection.
Chemistry
PUBLISHED: 07-24-2013
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A new dinuclear Ru(II) polypyridyl complex, [(bpy)2 Ru(H2 bpip)Ru(bpy)2 ](4+) (RuH2 bpip, bpy=2,2-bipyridine, H2 bpip=2,6-pyridyl(imidazo[4,5-f][1,10]phenanthroline), was developed to act as a one- and two-photon luminescent probe for biological Cu(2+) detection. This Ru(II) complex shows a significant two-photon absorption cross section (400?GM) and displays a remarkable one- and two-photon luminescence switch in the presence of Cu(2+) ions. Importantly, RuH2 bpip can selectively recognise Cu(2+) in aqueous media in the presence of other abundant cellular cations (such as Na(+) , K(+) , Mg(2+) , and Ca(2+) ), trace metal ions in organisms (such as Zn(2+) , Ag(+) , Fe(3+) , Fe(2+) , Ni(2+) , Mn(2+) , and Co(2+) ), prevalent toxic metal ions in the environment (such as Cd(2+) , Hg(2+) , and Cr(3+) ), and amino acids, with high sensitivity (detection limit?3.33×10(-8) ?M) and a rapid response time (?15?s). The biological applications of RuH2 bpip were also evaluated and it was found to exhibit low cytotoxicity, good water solubility, and membrane permeability; RuH2 bpip was, therefore, employed as a sensing probe for the detection of Cu(2+) in living cells and zebrafish.
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Self-activating nuclease and anticancer activities of copper(II) complexes with aryl-modified 2,6-di(thiazol-2-yl)pyridine.
Dalton Trans
PUBLISHED: 07-10-2013
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Three mononuclear copper complexes [Cu(PDTP)Cl2] (PDTP = 4-phenyl-2,6-di(thiazole-2-yl)pyridine, CuPDTP), [Cu(ADTP)Cl2] (ADTP = 4-(anthracen-9-yl)-2,6-di(thiazole-2-yl)pyridine, CuADTP) and [Cu(BFDTP)Cl2] (BFDTP = 4-(benzofuran-2-yl)-2,6-di(thiazole-2-yl)pyridine, CuBFDTP) were synthesized and characterized. The X-ray single crystallography results indicated that the Cu(II) ions showed slightly distorted square pyramid coordination environments, and the ligands deviated from ideal planarity in all three compounds. Based on the DNA binding studies, it was demonstrated that these three complexes exhibited weak DNA binding strengths, which were most likely groove binding modes. CuPDTP, CuADTP and CuBFDTP induced efficient DNA cleavage in the dark without the addition of external catalysts (oxidant or reductant). In contrast, in the presence of reducing or oxidizing agents, the nuclease activities increased more than 10-fold. Mechanistic investigations revealed the participation of reactive oxygen species, which can be trapped by ROS radical scavengers and ROS sensors. In the same experimental conditions, the free ligands and CuCl2 did not display any DNA cleaving activity. This result indicates that the complexes, rather than their components, play a significant role in the nuclease reaction process and that DNA cleavage may be initiated in an oxidative pattern. The proposed mechanism was attributed to the in situ activation of molecular oxygen by the oxidation of the copper complexes. In the MTT cytotoxicity studies, the three Cu(II) complexes exhibited an antitumor activity against the HeLa, BEL-7402 and HepG2 tumor cell lines. The HeLa cells treated with Cu(II) complexes demonstrated marked changes in their nuclear morphology, which were detected by Hoechst 33258 nuclear staining and acridine orange/ethidium bromide (AO/EB) staining assays. Nuclear chromatin cleavage also was observed from alkaline single-cell gel electrophoresis (comet assay).
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What is Visualize?

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

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

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