JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
CDKL2 promotes epithelial-mesenchymal transition and breast cancer progression.
Oncotarget
PUBLISHED: 10-22-2014
Show Abstract
Hide Abstract
The epithelial-mesenchymal transition (EMT) confers mesenchymal properties on epithelial cells and has been closely associated with the acquisition of aggressive traits by epithelial cancer cells. To identify novel regulators of EMT, we carried out cDNA screens that covered 500 human kinases. Subsequent characterization of candidate kinases led us to uncover cyclin-dependent kinase-like 2 (CDKL2) as a novel potent promoter for EMT and breast cancer progression. CDKL2-expressing human mammary gland epithelial cells displayed enhanced mesenchymal traits and stem cell-like phenotypes, which was acquired through activating a ZEB1/E-cadherin/?-catenin positive feedback loop and regulating CD44 mRNA alternative splicing to promote conversion of CD24high cells to CD44high cells. Furthermore, CDKL2 enhanced primary tumor formation and metastasis in a breast cancer xenograft model. Notably, CDKL2 is expressed significantly higher in mesenchymal human breast cancer cell lines than in epithelial lines, and its over-expression/amplification in human breast cancers is associated with shorter disease-free survival. Taken together, our study uncovered a major role for CDKL2 in promoting EMT and breast cancer progression.
Related JoVE Video
Adipocyte Lipolysis-stimulated Interleukin-6 Production Requires Sphingosine Kinase 1 Activity.
J. Biol. Chem.
PUBLISHED: 09-24-2014
Show Abstract
Hide Abstract
Adipocyte lipolysis can increase the production of inflammatory cytokines such as interleukin-6 (IL-6) that promote insulin resistance. However, the mechanisms that link lipolysis with inflammation remain elusive. Acute activation of ?3-adrenergic receptors (ADRB3) triggers lipolysis and up-regulates production of IL-6 in adipocytes, and both of these effects are blocked by pharmacological inhibition of hormone-sensitive lipase. We report that stimulation of ADRB3 induces expression of sphingosine kinase 1 (SphK1) and increases sphingosine 1-phosphate production in adipocytes in a manner that also depends on hormone-sensitive lipase activity. Mechanistically, we found that adipose lipolysis-induced SphK1 up-regulation is mediated by the c-Jun N-terminal kinase (JNK)/activating protein-1 signaling pathway. Inhibition of SphK1 by sphingosine kinase inhibitor 2 diminished the ADRB3-induced IL-6 production both in vitro and in vivo. Induction of IL-6 by ADRB3 activation was suppressed by siRNA knockdown of Sphk1 in cultured adipocytes and was severely attenuated in Sphk1 null mice. Conversely, ectopic expression of SphK1 increased IL-6 expression in adipocytes. Collectively, these data demonstrate that SphK1 is a critical mediator in lipolysis-triggered inflammation in adipocytes.
Related JoVE Video
ORCA-010, a novel potency-enhanced oncolytic adenovirus, exerts strong antitumor activity in preclinical models.
Hum. Gene Ther.
PUBLISHED: 09-17-2014
Show Abstract
Hide Abstract
Improving the antitumor potency of current oncolytic adenoviruses represents one of the major challenges in development of these viruses for clinical use. We have generated an oncolytic adenovirus carrying the safety-enhancing E1A?24 deletion, the potency-enhancing T1 mutation, and the infectivity-enhancing fiber RGD modification. The results of in vitro cytotoxicity assays on 15 human cancer cell lines derived from different tumor types demonstrated that ORCA-010 is more potent than Ad5-?24RGD or ONYX-015. As ORCA-010 will initially be developed for the treatment of prostate cancer, selectivity experiments were performed using primary human prostate cells. ORCA-010 killed cancer cells more effectively than these primary human cells. In both primary prostate fibroblasts and epithelial cells, ORCA-010 was as safe as Ad5-?24RGD. Evaluation of ORCA-010 in in vivo xenograft tumor models in nude mice showed that ORCA-010 significantly inhibited growth of prostate, lung, and ovarian tumors and conferred prolonged survival of tumor-bearing animals. Furthermore, we observed a substantial increase in infectious viral particles in tumors injected with ORCA-010. The number of infectious viral particles increased after treatment and infectious particles remained present up to at least 4 weeks posttreatment. Intratumoral virus replication was associated with substantial necrosis and fibrosis. In conclusion, ORCA-010 is more potent than earlier generation oncolytic adenoviruses, without demonstrating increased toxicity. ORCA-010 exerted strong in vivo antitumor activity and is therefore a suitable candidate for clinical evaluation.
Related JoVE Video
Size-dependent patterned recognition and extraction of metal ions by a macrocyclic aromatic pyridone pentamer.
Chem. Commun. (Camb.)
PUBLISHED: 09-10-2014
Show Abstract
Hide Abstract
A macrocyclic aromatic pyridine pentamer was found to exhibit patterned recognition of metal ions and efficiently extract larger ions, such as Cs(+), Ba(2+), Tl(+), Au(+), K(+) and Rb(+) preferentially over the other 18 smaller metal ions from the aqueous phase into the chloroform layer.
Related JoVE Video
Co-molten solvothermal method for synthesizing chalcopyrite CuFe(1-x)Cr(x)S? (x ? 0.4): high photocatalytic activity for the reduction of nitrate ions.
Dalton Trans
PUBLISHED: 09-05-2014
Show Abstract
Hide Abstract
In literature, it is very difficult to obtain sulfides with Cr(3+) in tetrahedral coordination. Here, a thiourea-oxalic acid co-molten solvothermal method was applied to synthesize chalcopyrite CuFe(1-x)Cr(x)S2 (x ? 0.4) solid solutions. We propose that oxalic acid plays an important role in the crystallization of CuFe(1-x)Cr(x)S2 and can considerably restrain the formation of other undesirable impurities. The successful incorporation of Cr(3+) was confirmed by powder XRD, SEM and EDX mapping (2D elemental distribution). The UV-Vis reflectance spectra of CuFe(1-x)Cr(x)S2 suggest that the bandgap energies decrease from 0.80 to 0.61 eV along with an increase in the Cr(3+) concentration. All the CuFe(1-x)Cr(x)S2 (0 ? x ? 0.4) samples show considerably higher photocatalytic activities than P25 toward the reduction of nitrate ions in aqueous solution. We speculate that the thiourea-oxalic acid co-molten method may not only be effective to synthesize Fe(3+)-Cr(3+) sulfides, but can also be helpful to incorporate Cr(3+) to other sulfide systems with MS4 tetrahedra.
Related JoVE Video
Microstructural modifications induced by accelerated aging and lipid absorption in remelted and annealed UHMWPEs for total hip arthroplasty.
J Biomater Appl
PUBLISHED: 08-31-2014
Show Abstract
Hide Abstract
Three types of commercially available ultra-high molecular weight polyethylene (UHMWPE) acetabular cups currently used in total hip arthroplasty have been studied by means of Raman micro-spectroscopy to unfold the microstructural modification induced by the oxidative degradation after accelerated aging with and without lipid absorption. The three investigated materials were produced by three different manufacturing procedures, as follows: irradiation followed by remelting, one-step irradiation followed by annealing, 3-step irradiation and annealing. Clear microstructural differences were observed in terms of phase contents (i.e. amorphous, crystalline and intermediate phase fraction). The three-step annealed material showed the highest crystallinity fraction in the bulk, while the remelted polyethylene is clearly characterized by the lowest content of crystalline phase and the highest content of amorphous phase. After accelerated aging either with or without lipids, the amount of amorphous phase decreased in all the samples as a consequence of the oxidation-induced recrystallization. The most remarkable variations of phase contents were detected in the remelted and in the single-step annealed materials. The presence of lipids triggered oxidative degradation especially in the remelted polyethylene. Such experimental evidence might be explained by the highest amount of amorphous phase in which lipids can be absorbed prior to accelerated aging. The results of these spectroscopic characterizations help to rationalize the complex effect of different irradiation and post-irradiation treatments on the UHMWPE microstructure and gives useful information on how significantly any single step of the manufacturing procedures might affect the oxidative degradation of the polymer.
Related JoVE Video
Tumor suppressor microRNA-27a in colorectal carcinogenesis and progression by targeting SGPP1 and Smad2.
PLoS ONE
PUBLISHED: 08-28-2014
Show Abstract
Hide Abstract
The aberrant expression of microRNAs (miRNAs) is associated with colorectal carcinogenesis, but the underlying mechanisms are not clear. This study showed that the miRNA-27a (miR-27a) was significantly reduced in colorectal cancer tissues and colorectal cancer cell lines, and that the reduced miR-27a was associated with distant metastasis and colorectal cancer clinical pathological stages-miR-27a was lower at stages III/IV than that at stage II. Bioinformatic and systemic biological analysis predicted several targets of miR-27a, among them SGPP1 and Smad2 were significantly affected. SGPP1 and Smad2 at mRNA and protein levels were negatively correlated with miR-27a in human colorectal cancer tissues and cancer cell lines. Increased miR-27a significantly repressed SGPP1 and Smad2 at transcriptional and translational levels. Functional studies showed that increasing miR-27a inhibited colon cancer cell proliferation, promoted apoptosis and attenuated cell migration, which were also linked to downregulation of p-STAT3 and upregulation of cleaved caspase 3. In vivo, miR-27a inhibited colon cancer cell growth in tumor-bearing mice. Taken together, this study has revealed miR-27a as a tumor suppressor and has identified SGPP1 and Smad2 as novel targets of miR-27a, linking to STAT3 for regulating cancer cell proliferation, apoptosis and migration in colorectal cancer. Therefore, miR-27a could be a useful biomarker for monitoring colorectal cancer development and progression, and also could have a therapeutic potential by targeting SGPP1, Smad2 and STAT3 for colorectal cancer therapy.
Related JoVE Video
Electric tuning of the surface and quantum well states in Bi2Se3 films: a first-principles study.
J Phys Condens Matter
PUBLISHED: 08-28-2014
Show Abstract
Hide Abstract
Based on first-principles calculations in the framework of van der Waals density functional theory, we find that giant, Rashba-like spin splittings can be induced in both the surface states and quantum well states of thin Bi2Se3 films by application of an external electric field. The charge is redistributed so that the Dirac cones of the upper and lower surfaces become nondegenerate and completely gapless. Interestingly, a momentum-dependent spin texture is developed on the two surfaces of the films. Some of the quantum well states, which reside in the middle of the Bi2Se3 film under zero field, are driven to the surface by the electric field. The Rashba splitting energy has a highly non-linear dependence on the momentum and the electric field due to the large contribution of the high-order Rashba terms, which suggests complex spin dynamics in the thin films of Bi2Se3 under an electric field.
Related JoVE Video
No-go theorems for unitary and interacting partially massless spin-two fields.
Phys. Rev. Lett.
PUBLISHED: 08-27-2014
Show Abstract
Hide Abstract
We examine the generic theory of a paratially massless (PM) spin-two field interacting with gravity in four dimensions from a bottom-up perspective. By analyzing the most general form of the Lagrangian, we first show that if such a theory exists, its de Sitter background must admit either so(1,5) or so(2,4) global symmetry depending on the relative sign of the kinetic terms: the former for a positive sign the latter for a negative sign. Further analysis reveals that the coupling constant of the PM cubic self-interaction must be fixed with a purely imaginary number in the case of a positive sign. We conclude that there cannot exist a unitary theory of a PM spin-two field coupled to Einstein gravity with a perturbatively local Lagrangian. In the case of a negative sign we recover conformal gravity. As a special case of our analysis, it is shown that the PM limit of massive gravity also lacks the PM gauge symmetry.
Related JoVE Video
Arsenic trioxide and resveratrol show synergistic anti-leukemia activity and neutralized cardiotoxicity.
PLoS ONE
PUBLISHED: 08-21-2014
Show Abstract
Hide Abstract
Cardiotoxicity is an aggravating side effect of many clinical antineoplastic agents such as arsenic trioxide (As2O3), which is the first-line treatment for acute promyelocytic leukemia (APL). Clinically, drug combination strategies are widely applied for complex disease management. Here, an optimized, cardiac-friendly therapeutic strategy for APL was investigated using a combination of As2O3 and genistein or resveratrol. Potential combinations were explored with respect to their effects on mitochondrial membrane potential, reactive oxygen species, superoxide dismutase activity, autophagy, and apoptosis in both NB4 cells and neonatal rat left ventricular myocytes. All experiments consistently suggested that 5 µM resveratrol remarkably alleviates As2O3-induced cardiotoxicity. To achieve an equivalent effect, a 10-fold dosage of genistein was required, thus highlighting the dose advantage of resveratrol, as poor bioavailability is a common concern for its clinical application. Co-administration of resveratrol substantially amplified the anticancer effect of As2O3 in NB4 cells. Furthermore, resveratrol exacerbated oxidative stress, mitochondrial damage, and apoptosis, thereby reflecting its full range of synergism with As2O3. Addition of 5 µM resveratrol to the single drug formula of As2O3 also further increased the expression of LC3, a marker of cellular autophagy activity, indicating an involvement of autophagy-mediated tumor cell death in the synergistic action. Our results suggest a possible application of an As2O3 and resveratrol combination to treat APL in order to achieve superior therapeutics effects and prevent cardiotoxicity.
Related JoVE Video
Astragaloside IV inhibits platelet-derived growth factor-BB-stimulated proliferation and migration of vascular smooth muscle cells via the inhibition of p38 MAPK signaling.
Exp Ther Med
PUBLISHED: 08-14-2014
Show Abstract
Hide Abstract
Astragaloside IV (AS-IV), the major active component extracted from Astragalus membranaceus, has been demonstrated to exhibit protective effects on the cardiovascular, immune, digestive and nervous systems; thus, has been widely used in traditional Chinese medicine. Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) is closely associated with the initiation and progression of cardiovascular diseases, including atherosclerosis and restenosis. However, the effects of AS-IV on VSMCs remain unknown. For the first time, the present study demonstrated that AS-IV markedly suppressed platelet-derived growth factor (PDGF)-BB-stimulated cellular proliferation and migration of HDMEC-a human dermal VSMCs (HDVSMCs). Further investigation into the underlying molecular mechanisms demonstrated that the administration of AS-IV attenuated the PDGF-BB-stimulated switch of HDVSMCs into a proliferative phenotype. Furthermore, AS-IV inhibited the PDGF-BB-induced expression of cell cycle-associated proteins, as well as the upregulation of matrix metalloproteinase (MMP)2, but not MMP9. In addition, AS-IV was shown to downregulate the activation of p38 mitogen-activated protein kinase (MAPK) signaling induced by PDGF-BB in HDVSMCs. Therefore, the observations of the present study indicate that AS-IV inhibits PDGF-BB-stimulated VSMC proliferation and migration, possibly by inhibiting the activation of the p38 MAPK signaling pathway. Thus, AS-IV may be useful for the treatment of vascular diseases.
Related JoVE Video
[Experimental study on novel hybrid artificial trachea transplantation].
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi
PUBLISHED: 07-22-2014
Show Abstract
Hide Abstract
We developed and designed a new type of artificial trachea. The basic structure of the artificial trachea was polytetrafluoroethylene vascular prosthesis linked with titanium rings on both sides. Dualmesh was sutured on titanium rings. This experimentation follows the replacement of trachea in dogs with a combined artificial trachea to investigate the feasibility of this type of prosthesis. Sixteen dogs were implanted with the combined artificial trachea after resection of 5 cm of cervical trachea. The 5 cm-long trachea of dogs on the necks were resected and the reconstruction of the defect of the trachea was performed with trachea prosthesis. According to the method of trachea reconstruction, the models were divided into 2 groups, artificial trachea implantation group (the control group, n = 8) and group of artificial trachea implantation with growth factor (the experimental group, n = 8). Then computer tomography scan (CT), bronchoscope and pathologic examination were conducted periodically to observe the healing state of the hybrid artificial trachea. None of the dogs died during operation of cervical segmental trachea construction. But four dogs in the control group died of apnea in succession because artificial trachea was displaced and the lumen was obstructed, while 2 dogs died in the experimental group. In the first month there was granulation around anastomosis with slight stenosis. The rest of dogs were well alive until they were sacrificed 14 months later. The mean survival time of the experimental group was longer than that of the control group. The rate of infection, anastomotic dehiscence, severe stenosis and accidental death in the experimental group were lower than the control group (P < 0.05). Artificial trachea was encapsulated by fibrous tissue and no mucous membrane was seen in the lumen of the artificial trachea. The artificial trachea can be used to reconstruction of the defect of the trachea with long-term survival of the animals. The unique design of artificial trachea reduces stenosis around anastomosis effectively but infections and split or displacement of the artificial trachea are still major problems affecting long-term survival of the animals. Application of growth factors to a certain extent promotes tissue healing by changing the local environment.
Related JoVE Video
VEGF-mediated suppression of cell proliferation and invasion by miR-410 in osteosarcoma.
Mol. Cell. Biochem.
PUBLISHED: 07-16-2014
Show Abstract
Hide Abstract
MicroRNAs (miRNAs) are small non-coding RNAs that post-transcriptionally regulate gene expression. The aberrant expression of miRNA has become a major focus in cancer research. This study aimed to investigate the importance of miR-410 in the diagnosis and therapy of osteosarcoma (OS). Western blot analysis showed that the expression of VEGF was higher in Saos-2 and MG-63 cells than that in three other OS cell lines. We also found that miR-410 was lowly expressed and inversely correlated with VEGF expression in OS specimens. Over-expression of miR-410 had a greater repression on VEGF expression than other candidate VEGF-targeting miRNAs. Luciferase reporter assay demonstrated that miR-410 directly decreased VEGF expression by targeting its 3'-untranslated region. Further investigation demonstrated the regulation of miR-410 in OS cells via VEGF. In vitro MTT assay, Transwell, and flow cytometry showed that transfection of the miR-410 expression plasmid inhibited cell proliferation and contributed to apoptosis in OS cells. Moreover, restoration of VEGF reversed the effect of miR-410 on OS cells, and upregulated the expression of phosphorylated AKT. Finally, overexpression of miR-410 also showed a negative effect on tumor growth in vivo. Our findings suggest a cooperative relationship between miR-410 and VEGF in OS cell regulation. This information may help researchers to better understand miRNA regulation in cancer and provide a rationale for developing miRNA-based strategies for OS treatment.
Related JoVE Video
Feasibility of constant dose rate VMAT in the treatment of nasopharyngeal cancer patients.
Radiat Oncol
PUBLISHED: 07-16-2014
Show Abstract
Hide Abstract
PurposeTo investigate the feasibility of constant dose rate volumetric modulated arc therapy (CDR-VMAT) in the treatment of nasopharyngeal cancer (NPC) patients and to introduce rotational arc radiotherapy for linacs incapable of dose rate variation.Materials and methodsTwelve NPC patients with various stages treated previously using variable dose rate (VDR) VMAT were enrolled in this study. CDR-VMAT, VDR-VMAT and mutlicriteria optimization (MCO) VMAT plans were generated for each patient on RayStation treatment planning system with identical objective functions and the dosimetric differences among these three planning schemes were evaluated and compared. Non dosimetric parameters of optimization time, delivery time and delivery accuracy were also evaluated.ResultsThe planning target volume of clinical target volume (PTV-CTV) coverage of CDR-VMAT was a bit inferior to those of VDR- and MCO-VMAT. The V93 (p¿=¿0.01) and V95 (percent volume covered by isodose line) (p¿=¿0.04) for CDR-VMAT, VDR-VMAT and MCO-VMAT were 98.74%¿±¿0.31%, 99.76%¿±¿0.16%, 99.38%¿±¿0.43%, and 98.40%¿±¿0.48%, 99.53%¿±¿0.28%, 99.07%¿±¿0.52%, respectively.. However, the CDR-VMAT showed a better dose homogeneity index (HI) (p¿=¿0.01) in PTV-CTV. No significant difference in other target coverage parameters was observed. There was no significant difference in OAR sparing among these three planning schemes except for a higher maximum dose (Dmax) on the brainstem for CDR-VMAT. The brainstem Dmax of CDR-VMAT, VDR-VMAT and MCO-VMAT were 54.26¿±¿3.21 Gy, 52.19¿±¿1.65 Gy, and 52.79¿±¿4.77 Gy, respectively. The average delivery time (p¿<¿0.01) and the average percent ¿ passing rates (p¿=¿0.02) of CDR-VMAT, VDR-VMAT and MCO-VMAT were 7.01¿±¿0.43 min, 4.75¿±¿0.07 min, 4.01¿±¿0.28 min, and 95.75%¿±¿2.57%, 97.65%¿±¿1.45%, 97.36%¿±¿2.45%, respectively.ConclusionCDR-VMAT offers an additional option of rotational arc radiotherapy for linacs incapable of dose rate variation with a lower initial cost. Its plan quality was acceptable but should be thoroughly checked compared with VDR-VMAT and MCO-VMAT in the treatment of NPC.
Related JoVE Video
Is the contribution of cis and trans protonated 5-methylcytosine-SO3(-) isomers equal in the conversion to thymine-SO3(-) under bisulfite conditions? A theoretical perspective.
Phys Chem Chem Phys
PUBLISHED: 07-01-2014
Show Abstract
Hide Abstract
Cytosine (Cyt) can be converted to 5-methylcytosine (5-MeCyt) in CpG sequences of DNA. Conventional bisulfite sequencing can discriminate Cyt from 5-MeCyt, however inappropriate conversion of 5-MeCyt to thymine and a failure to convert Cyt to uracil always occur when Cyt and 5-MeCyt are treated with bisulfite, which would lead to erroneous estimates of DNA methylation densities. Here, the direct hydrolytic deamination of cis (paths A-C) and trans (paths A'-C') 5-MeCytN3(+)-SO3(-) isomers with bisulfite have been explored at the MP2/6-311++G(3df,3pd)//B3LYP/6-311++G(d,p) level. The activation free energies (?G(s-a?)) of the cis and trans 5-MeCytN3(+)-SO3(-) isomers' paths exhibit no obvious differences, implying both isomers may make an equal contribution to the hydrolytic deamination of 5-MeCyt under bisulfite conditions. It is greatly expected that these results could aid experimental scientists to explore new methods to avoid the formation of the deaminated reactants (5-MeCytN3(+)-SO3(-)). Meanwhile, the HSO3(-)-induced direct hydrolytic deamination of cis and trans 5-MeCytN3(+)-SO3(-) isomers is represented by paths A and A', respectively, and has been further explored in the presence of two water molecules. It was found that the contribution of two water molecules renders the HSO3(-)-induced direct hydrolytic deamination of cis and trans 5-MeCytN3(+)-SO3(-) isomers by paths A and A' favourable. In addition, the ?G(s-a?) values (85.74-85.34 kJ mol(-1)) of the rate-limiting steps of the two water-mediated paths A and A' are very close to that of the theoretical value for CytN3(+)-SO3(-) (88.18 kJ mol(-1)), implying that the free barrier gap between Cyt and 5-MeCyt is very small under bisulfite conditions. This further suggests that bisulfite sequencing technology may be easily influenced by the external environment.
Related JoVE Video
A novel parainfluenza virus type 3 (PIV3) identified from goat herds with respiratory diseases in eastern China.
Vet. Microbiol.
PUBLISHED: 06-24-2014
Show Abstract
Hide Abstract
Parainfluenza virus type 3 (PIV3) is one of the most important viral respiratory pathogens for humans and for many animals, but goat infection has been rarely reported. Starting in Aug 2013, goats in the Jiangsu and Anhui provinces of eastern China suffered severe respiratory diseases. In order to identify the causative agent, numerous related pathogens were tested with RT-PCR or PCR. A unique PIV3 strain was detected in most of the clinical nasal swabs or serum samples. The virus was isolated on MDBK cells and characterized by RT-PCR, nucleotide sequence analysis and hemagglutination test. The entire M and F gene coding regions, HN, 5'-UTR-N and L gene fragments were amplified using pairs of degenerate primers. Nucleotide, amino acid sequence alignments and phylogenetic analyses based on these genes indicated that the goat-derived PIV3 strain was distinct from previously reported BPIV3 genotypes and HPIV3 strains. The novel isolate, named JS2013, might be a potentially new member of the respirovirus genus. Goats were experimentally infected with JS2013 culture. The virus-inoculated goats displayed coughing and nasal discharges that were related to respiratory diseases. Viremia and virus shedding were detected during 4-10 days post-inoculation (dpi). Virus-specific HI antibodies became positive from 14dpi. This is the first report of the detection of PIV3 from Chinese goat herds and genetic and pathogenetic characterization of the novel goat-derived PIV3.
Related JoVE Video
Relaxant effect of flavonoid naringenin on contractile activity of rat colonic smooth muscle.
J Ethnopharmacol
PUBLISHED: 06-19-2014
Show Abstract
Hide Abstract
Disturbed gastrointestinal (GI) motility can be associated with smooth muscle abnormalities and dysfunction. Exploring innovative approaches that can modulate the disturbed colonic motility are of great importance for clinical therapeutics. Naringenin, a flavonoid presented in many traditional Chinese herbal medicines, has been shown to have a relaxant effect on different smooth muscles. The aim of the present study was to investigate the effect of naringenin on regulation of GI motility.
Related JoVE Video
The complete mitochondrial genome of Aythya ferina (Anatidae: Aythya).
Mitochondrial DNA
PUBLISHED: 06-19-2014
Show Abstract
Hide Abstract
Abstract The mitochondrial genome of Aythya ferina (Anatidae: Aythya) is a circular molecule of 16,616?bp in length, containing 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and one control region (D-loop). Overall base composition of the complete mitochondrial DNA was 29.42% A, 22.19% T, 32.83% C and 15.56% G. All the genes in A. ferina were distributed on the H-strand, except for the ND6 subunit gene and eight tRNA genes which were encoded on the L-strand.
Related JoVE Video
The sheep genome illuminates biology of the rumen and lipid metabolism.
Science
PUBLISHED: 06-07-2014
Show Abstract
Hide Abstract
Sheep (Ovis aries) are a major source of meat, milk, and fiber in the form of wool and represent a distinct class of animals that have a specialized digestive organ, the rumen, that carries out the initial digestion of plant material. We have developed and analyzed a high-quality reference sheep genome and transcriptomes from 40 different tissues. We identified highly expressed genes encoding keratin cross-linking proteins associated with rumen evolution. We also identified genes involved in lipid metabolism that had been amplified and/or had altered tissue expression patterns. This may be in response to changes in the barrier lipids of the skin, an interaction between lipid metabolism and wool synthesis, and an increased role of volatile fatty acids in ruminants compared with nonruminant animals.
Related JoVE Video
Effector CD4 T-cell transition to memory requires late cognate interactions that induce autocrine IL-2.
Nat Commun
PUBLISHED: 06-03-2014
Show Abstract
Hide Abstract
It is unclear how CD4 T-cell memory formation is regulated following pathogen challenge, and when critical mechanisms act to determine effector T-cell fate. Here, we report that following influenza infection most effectors require signals from major histocompatibility complex class II molecules and CD70 during a late window well after initial priming to become memory. During this timeframe, effector cells must produce IL-2 or be exposed to high levels of paracrine or exogenously added IL-2 to survive an otherwise rapid default contraction phase. Late IL-2 promotes survival through acute downregulation of apoptotic pathways in effector T cells and by permanently upregulating their IL-7 receptor expression, enabling IL-7 to sustain them as memory T cells. This new paradigm defines a late checkpoint during the effector phase at which cognate interactions direct CD4 T-cell memory generation.
Related JoVE Video
A macrophage-stimulating compound from a screen of microbial natural products.
J. Antibiot.
PUBLISHED: 05-20-2014
Show Abstract
Hide Abstract
Rising rates of antibiotic resistance in bacterial pathogens is a medical crisis of global concern that necessitates the development of new treatment strategies. We have isolated a natural product with macrophage-stimulating activity from a screen of microbially produced bioactive molecules. Streptazolin increased bacterial killing and elaboration of immunostimulatory cytokines by macrophages in vitro. Furthermore, we show that streptazolin stimulates the macrophage nuclear factor ?B (NF-?B) pathway via phosphatidylinositide 3-kinase (PI3K) signaling, and that the conjugated diene moiety is essential for stimulatory activity. Immunostimulatory molecules like streptazolin represent entries into new treatment paradigms to address the challenge of antibiotic resistance.The Journal of Antibiotics advance online publication, 2 July 2014; doi:10.1038/ja.2014.83.
Related JoVE Video
Systematic study of Cr3+ substitution into octahedra-based microporous aluminoborates.
Inorg Chem
PUBLISHED: 05-20-2014
Show Abstract
Hide Abstract
Single crystals of pure aluminoborate PKU-1 (Al3B6O11(OH)5·nH2O) were obtained, and the structure was redetermined by X-ray diffraction. There are three independent Al atoms in the R3 structure model, and Al3 locates in a quite distorted octahedral environment, which was evidenced by (27)Al NMR results. This distortion of Al3O6 octahedra release the strong static stress of the main framework and leads to a symmetry lowering from the previously reported R3 to the presently reported R3. We applied a pretreatment to prepare Al(3+)/Cr(3+) aqueous solutions; as a consecquence, a very high Cr(3+)-to-Al(3+) substitution content (?50 atom %) in PKU-1 can be achieved, which is far more than enough for catalytic purposes. Additionally, the preference for Cr(3+) substitution at the Al1 and Al2 sites was observed in the Rietveld refinements of the powder X-ray data of PKU-1:0.32Cr(3+). We also systematically investigated the thermal behaviors of PKU-1:xCr(3+) (0 ? x ? 0.50) by thermogravimetric-differential scanning calorimetry, in situ high-temperature XRD in vacuum, and postannealing experiments in furnace. The main framework of Cr(3+)-substituted PKU-1 could be partially retained at 1100 °C in vacuum. When 0.04 ? x ? 0.20, PKU-1:xCr(3+) transferred to the PKU-5:xCr(3+) (Al4B6O15:xCr(3+)) structure at ?750 °C by a 5 h annealing in air. Further elevating the temperature led to a decomposition into the mullite phase, Al4B2O9:xCr(3+). For x > 0.20 in PKU-1:xCr(3+), the heat treatment led to a composite of Cr(3+)-substituted PKU-5 and Cr2O3, so the doping upper limit of Cr(3+) in PKU-5 structure is around 20 atom %.
Related JoVE Video
Girdin, an actin-binding protein, is critical for migration, adhesion, and invasion of human glioblastoma cells.
J. Neurochem.
PUBLISHED: 05-19-2014
Show Abstract
Hide Abstract
Girdin, an actin-binding protein, possesses versatile functions in a multitude of cellular processes. Although several studies have shown that Girdin is involved in the cell DNA synthesis, actin cytoskeleton rearrangement, and cell motility, the molecular mechanisms of Girdin in tumor development and progression remain elusive. In this study, through over-expression and siRNA experiments, we found that Girdin increased migration of LN229 human glioblastoma cells. On the other hand, reducing Girdin impaired F-actin polymerization, which is essential for cell morphogenesis and motility. Matrix metalloproteinase 2, critical in human glioma migration and invasion, was down-regulated upon Girdin reduction and led to decreased invasion in vitro and in vivo. In addition, silencing Girdin expression impaired the phosphorylation of two important adhesion molecules, integrin ?1 and focal adhesion kinase, resulting in cell adhesion defects. Our immunohistochemical study on human gliomas tissue sections indicated that Girdin expression was positively related with glioma malignancy, supporting the in vitro and in vivo results from cell lines. Collectively, our findings suggest a critical role for Girdin in glioma infiltration. We show that reduction of Girdin, an actin-binding protein, leads to impaired F-actin polymerization and down-regulated expression of matrix metallopeptidase protein 2 (MMP-2), phosphorylated integrin ?1, and phosphorylated focal adhesion kinase (FAK), which resulted in decreased migration, adhesion, and invasion of glioblastoma cells. Girdin was positively correlated with glioma malignancy and negatively associated with clinical prognosis, suggesting Girdin as a critical regulator in glioma infiltration.
Related JoVE Video
Improved linearity in down-converted analog photonic link by polarization manipulation.
Opt Lett
PUBLISHED: 05-03-2014
Show Abstract
Hide Abstract
A method to improve the linearity of the down-converted analog photonic link is proposed and experimentally demonstrated, consisting of two phase modulators, a polarizer, and an optical filter. Down-conversion of a 10-GHz microwave signal to 100-MHz intermediate frequency is successfully achieved. By carefully optimizing the angles between the transverse-electric and transverse-magnetic modes, the third-order inter-modulation distortion (IMD3) is suppressed. The linearization method leads to a suppression of the IMD3 by more than 14 and 13 dB improvement of spurious-free dynamic range.
Related JoVE Video
[Expression change and significance of homebox gene-A10 in rat cryptorchidism].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 04-24-2014
Show Abstract
Hide Abstract
To explore the effects of HOXA10 gene expression in undescended and descended testis.
Related JoVE Video
Polyphenols from blueberries modulate inflammation cytokines in LPS-induced RAW264.7 macrophages.
Int. J. Biol. Macromol.
PUBLISHED: 04-04-2014
Show Abstract
Hide Abstract
Polyphenols including 3-glucoside/arabinoside/galactoside-based polymers of delphinidins, petunidins, peonidins, malvidins and cyanidins are one type of biological macromolecules, which are extraordinarily rich in blueberries. Anti-inflammatory activity of blueberry polyphenols (BPPs) was investigated by using lipopolysaccharide (LPS) induced RAW264.7 macrophages. The results showed that BPPs suppressed the gene expression of IL-1? (interleukin-1?), IL-6 and IL-12p35. The inhibition effect on IL-1? and IL-6 mRNA was most obvious at the concentration of 10-200?g/mL BPPs. But the inhibition effect on IL-12p35 mRNA was increased with the increasing concentration of BPPs. When fixed at 100?g/mL BPPs, the most significant inhibition on IL-1?, IL-6 and IL-12p35 mRNA expression was detected at 12-48h. In conclusion, BPPs exhibit anti-inflammation activity by mediating and modulating the balances in pro-inflammatory cytokines of IL-1?, IL-6, and IL-12.
Related JoVE Video
Accurate determination of the rotational constants of ultracold molecules using double photoassociation spectroscopy.
Opt Express
PUBLISHED: 03-26-2014
Show Abstract
Hide Abstract
We report on an accurate determination of the rotational constants of the ultracold long-range Cesium molecules in near dissociation domain. The scheme relies on a precise reference of the frequency difference in a double photoassociation spectroscopy induced by two laser beams based on an acoustic-optical modulator. The rotational constants are obtained by fitting a non-rigid rotor model into the frequency intervals of the neighboring rotational levels deduced from the reference.
Related JoVE Video
p-n junction CuO/BiVO? heterogeneous nanostructures: synthesis and highly efficient visible-light photocatalytic performance.
Dalton Trans
PUBLISHED: 03-20-2014
Show Abstract
Hide Abstract
A new strategy via coupling a polyol route with an oxidation process has been developed to successfully synthesize p-n junction CuO/BiVO4 heterogeneous nanostructures. The experimental results reveal that the as-prepared p-n junction CuO/BiVO4 heterogeneous nanostructures exhibit much higher visible-light-driven photocatalytic activity for the degradation of model dye rhodamine B (RhB) than the pure BiVO4 nanocrystals. The photocatalytic degradation rate (C/C0) of the RhB for p-n junction CuO/BiVO4 heterogeneous nanostructures is about two times higher than that of pure BiVO4 nanocrystals. The enhanced photocatalytic efficiency is attributed to a large number of p-n junctions in CuO/BiVO4 heterogeneous nanostructures, which effectively reduces the recombination of electrons and holes by charge transfer from n-type BiVO4 to the attached p-type CuO nanoparticles. This work not only provides an efficient route to enhance the visible-light-driven photocatalytic activity of BiVO4, but also offers a new strategy for fabricating p-n junction heterogeneous nanostructure photocatalysts, which are expected to show considerable potential application in solar-driven wastewater treatment and water splitting.
Related JoVE Video
Raman spectroscopic study of remelting and annealing-induced effects on microstructure and compressive deformation behavior of highly crosslinked UHMWPE for total hip arthroplasty.
J. Biomed. Mater. Res. Part B Appl. Biomater.
PUBLISHED: 03-19-2014
Show Abstract
Hide Abstract
Three-dimensional crystallographic morphologies were studied by means of confocal/polarized Raman spectroscopy as developed upon manufacturing in three different types of first and second generation highly crosslinked UHMWPE (HXLPE) acetabular liners. The impact of such microstructural characteristics on the deformation behavior of the liners was also evaluated and discussed from the viewpoint of molecular chain mobility. All the investigated liners showed similar microstructural transitions within the first 35 ?m below their surfaces in terms of crystallinity, molecular orientation, and crystalline anisotropy. Interestingly, different postirradiation heat treatments (remelting or annealing in single step or in sequential steps) led to clear differences in the subsurface microstructure among the three liners. Remelted liner possessed both lower bulk crystallinity and degree of molecular orientation as compared to the annealed liners. Sequentially, irradiated/annealed liner showed the highest degree of crystallinity and orientation among the studied liners. The peculiar microstructure of this latter liner exhibited the highest restoring (shape-recovery) force against the applied uniaxial strain. Accordingly, the present study suggests that the sequential irradiation and annealing offers an efficient way to obtain microstructure quite suitable for attaining high creep resistance. However, all the investigated liners exhibited the significantly low values of surface anisotropy, which could be equally efficient in minimizing strain-softening-assisted wear phenomena.
Related JoVE Video
Cell surface vimentin is an attachment receptor for enterovirus 71.
J. Virol.
PUBLISHED: 03-12-2014
Show Abstract
Hide Abstract
Enterovirus 71 (EV71) is a highly transmissible pathogenic agent that causes severe central nervous system diseases in infected infants and young children. Here, we reported that EV71 VP1 protein could bind to vimentin intermediate filaments expressed on the host cell surface. Soluble vimentin or an antibody against vimentin could inhibit the binding of EV71 to host cells. Accompanied with the reduction of vimentin expression on the cell surface, the binding of EV71 to cells was remarkably decreased. Further evidence showed that the N terminus of vimentin is responsible for the interaction between EV71 and vimentin. These results indicated that vimentin on the host cell surface may serve as an attachment site that mediated the initial binding and subsequently increased the infectivity of EV71.
Related JoVE Video
Prospective identification and culture of rat enteric neural stem cells (ENSCs).
Cytotechnology
PUBLISHED: 03-11-2014
Show Abstract
Hide Abstract
Hirschprung's disease (HD), a very common congenital abnormality in children, occurs mainly due to the congenital developmental defect of the enteric nervous system. The absence of enteric ganglia from the distal gut due to deletion in gut colonization by neural crest progenitor cells may lead to HD. The capacity to identify and isolate the enteric neuronal precursor cells from developing and mature tissues would enable the development of cell replacement therapies for HD. However, a mature method to culture these cells is a challenge. The present study aimed to propose a method to culture enteric neural stem cells (ENSCs) from the DsRed transgenic fetal rat gut. The culture medium used contained 15 % chicken embryo extract, basic fibroblast growth factor, and epidermal growth factor. ENSCs were cultured from embryonic day 18 in DsRed transgenic rat. Under inverted microscope and fluorescence staining, ENSCs proliferated to form small cell clusters on the second day of culture. The neurospheres-like structure were suspended in the medium, and there were some filaments between the adherent cells from day 3 to day 6 of the culture. The neurospheres were formed by ENSCs on day 8 of the culture. Network-like connections were formed between the adherent cells and differentiated cells after adding 10 % FBS. The differentiated cells were positive for neurofilament and glial fibrillary acidic protein antibodies. The present study established a method to isolate and culture ENSCs from E18 DsRed transgenic rats in the terminal stage of embryonic development. This study would offer a way to obtain plenty of cells for the future research on the transplantation of HD.
Related JoVE Video
Characterization of metabolites of sweroside in rat urine using ultra-high-performance liquid chromatography combined with electrospray ionization quadrupole time-of-flight tandem mass spectrometry and NMR spectroscopy.
J Mass Spectrom
PUBLISHED: 03-01-2014
Show Abstract
Hide Abstract
Sweroside, a major active iridoid in Swertia pseudochinensis Hara, is recognized as an effective agent in the treatment of liver injury. Based on previous reports, the relatively short half-life (64?min) and poor bioavailability (approximately 0.31%) in rats suggested that not only sweroside itself but also its metabolites could be responsible for the observed hepato-protective effect. However, few studies have been carried out on the metabolism of sweroside. Therefore, the present study aimed at identifying the metabolites of sweroside in rat urine after a single oral dose (100?mg/kg). With ultra-high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UHPLC/Q-TOF-MS), the metabolic profile revealed 11 metabolites in rat urine, including phase I, phase II and aglycone-related products. The chemical structures of metabolites were proposed based on accurate mass measurements of protonated or deprotonated molecules and their fragmentation patterns. Our findings showed that the aglycone of sweroside (M05) and its glucuronide conjugate (M06) were principal circulating metabolites in rats. While several other metabolic transformations, occurring via reduction, N-heterocyclization and N-acetylation after deglycosylation, were also observed. Two metabolites (M05 and M06) were isolated from the rat urine for structural elucidation and identifcation of reaction sites. Both M05 and M06 were characterized by (1) H, (13) C and two-dimensional nuclear magnetic resonance (NMR) spectroscopy. UHPLC/Q-TOF-MS analysis has provided an important analytical platform to gather metabolic profile of sweroside. Copyright © 2014 John Wiley & Sons, Ltd.
Related JoVE Video
Genome-wide comparison of genes involved in the biosynthesis, metabolism, and signaling of juvenile hormone between silkworm and other insects.
Genet. Mol. Biol.
PUBLISHED: 02-27-2014
Show Abstract
Hide Abstract
Juvenile hormone (JH) contributes to the regulation of larval molting and metamorphosis in insects. Herein, we comprehensively identified 55 genes involved in JH biosynthesis, metabolism and signaling in the silkworm (Bombyx mori) as well as 35 in Drosophila melanogaster, 35 in Anopheles gambiae, 36 in Apis mellifera, 47 in Tribolium castaneum, and 44 in Danaus plexippus. Comparative analysis showed that each gene involved in the early steps of the mevalonate (MVA) pathway, in the neuropeptide regulation of JH biosynthesis, or in JH signaling is a single copy in B. mori and other surveyed insects, indicating that these JH-related pathways or steps are likely conserved in all surveyed insects. However, each gene participating in the isoprenoid branch of JH biosynthesis and JH metabolism, together with the FPPS genes for catalyzing the final step of the MVA pathway of JH biosynthesis, exhibited an obvious duplication in Lepidoptera, including B. mori and D. plexippus. Microarray and real-time RT-PCR analysis revealed that different copies of several JH-related genes presented expression changes that correlated with the dynamics of JH titer during larval growth and metamorphosis. Taken together, the findings suggest that duplication-derived copy variation of JH-related genes might be evolutionarily associated with the variation of JH types between Lepidoptera and other insect orders. In conclusion, our results provide useful clues for further functional analysis of JH-related genes in B. mori and other insects.
Related JoVE Video
Aspergillomarasmine A overcomes metallo-?-lactamase antibiotic resistance.
Nature
PUBLISHED: 02-26-2014
Show Abstract
Hide Abstract
The emergence and spread of carbapenem-resistant Gram-negative pathogens is a global public health problem. The acquisition of metallo-?-lactamases (MBLs) such as NDM-1 is a principle contributor to the emergence of carbapenem-resistant Gram-negative pathogens that threatens the use of penicillin, cephalosporin and carbapenem antibiotics to treat infections. To date, a clinical inhibitor of MBLs that could reverse resistance and re-sensitize resistant Gram-negative pathogens to carbapenems has not been found. Here we have identified a fungal natural product, aspergillomarasmine A (AMA), that is a rapid and potent inhibitor of the NDM-1 enzyme and another clinically relevant MBL, VIM-2. AMA also fully restored the activity of meropenem against Enterobacteriaceae, Acinetobacter spp. and Pseudomonas spp. possessing either VIM or NDM-type alleles. In mice infected with NDM-1-expressing Klebsiella pneumoniae, AMA efficiently restored meropenem activity, demonstrating that a combination of AMA and a carbapenem antibiotic has therapeutic potential to address the clinical challenge of MBL-positive carbapenem-resistant Gram-negative pathogens.
Related JoVE Video
Modeling the selectivity of indoor pollution gases over N2 on covalent organic frameworks.
J Mol Model
PUBLISHED: 02-24-2014
Show Abstract
Hide Abstract
The selectivity of indoor pollution gases (including formaldehyde, benzene, and toluene) over N2 on a set of 37 covalent organic frameworks (COFs) was modeled by combining classical grand canonical Monte Carlo (GCMC) methods and periodic density functional theory with dispersion correction (DFT-D2). The pore volume, pore size, and the isosteric heat (Q st) of gases on COFs were investigated to explore the origin of the high selectivity of pollution gases over N2. We found that the size match between the pore of the COFs and the corresponding pollution gases is the key factor for high selectivity. Additionally, the Q st for the investigated four gases follows the order of toluene?>?benzene?>?formaldehyde?>?N2, which is consistent with the order of selectivity. Furthermore, the favorite sites and interaction energies of pollution gases on COFs were calculated by the periodic DFT-D2 method. Our simulation procedure offers an alternative approach with which to evaluate or design the best candidate porous materials in capture pollution gases.
Related JoVE Video
Characterization and expression patterns of small RNAs in synthesized Brassica hexaploids.
Plant Mol. Biol.
PUBLISHED: 02-24-2014
Show Abstract
Hide Abstract
Polyploidy has played an important role in promoting plant evolution through genomic merging and doubling. We used high-throughput sequencing to compare miRNA expression profiles between Brassica hexaploid and its parents. A total of 613, 784 and 742 known miRNAs were identified in Brassica rapa, Brassica carinata, and Brassica hexaploid, respectively. We detected 618 miRNAs were differentially expressed (log(2)Ratio ? 1, P ? 0.05) between Brassica hexaploid and its parents, and 425 miRNAs were non-additively expressed in Brassica hexaploid, which suggest a trend of non-additive miRNA regulation following hybridization and polyploidization. Remarkably, majority of the non-additively expressed miRNAs in the Brassica hexaploid are repressed, and there was a bias toward repression of B. rapa miRNAs, which is consistent with the progenitor-biased gene repression in the synthetic allopolyploids. In addition, we identified 653 novel mature miRNAs in Brassica hexaploid and its parents. Finally, we found that almost all the non-additive accumulation of siRNA clusters exhibited a low-parent pattern in Brassica hexaploid. Non-additive small RNA regulation is involved in a range of biological pathways, probably providing a driving force for variation and adaptation in allopolyploids.
Related JoVE Video
Open-framework gallium borate with boric and metaboric acid molecules inside structural channels showing photocatalysis to water splitting.
Inorg Chem
PUBLISHED: 02-10-2014
Show Abstract
Hide Abstract
An open-framework gallium borate with intrinsic photocatalytic activities to water splitting has been discovered. Small inorganic molecules, H3BO3 and H3B3O6, are confined inside structural channels by multiple hydrogen bonds. It is the first example to experimentally show the structural template effect of boric acid in flux synthesis.
Related JoVE Video
Microarray Analysis of the Juvenile Hormone Response in Larval Integument of the Silkworm, Bombyx mori.
Int J Genomics
PUBLISHED: 01-29-2014
Show Abstract
Hide Abstract
Juvenile hormone (JH) coordinates with 20-hydroxyecdysone (20E) to regulate larval growth and molting in insects. However, little is known about how this cooperative control is achieved during larval stages. Here, we induced silkworm superlarvae by applying the JH analogue (JHA) methoprene and used a microarray approach to survey the mRNA expression changes in response to JHA in the silkworm integument. We found that JHA application significantly increased the expression levels of most genes involved in basic metabolic processes and protein processing and decreased the expression of genes associated with oxidative phosphorylation in the integument. Several key genes involved in the pathways of insulin/insulin-like growth factor signaling (IIS) and 20E signaling were also upregulated after JHA application. Taken together, we suggest that JH may mediate the nutrient-dependent IIS pathway by regulating various metabolic pathways and further modulate 20E signaling.
Related JoVE Video
Identification and Expression Profiling of the BTB Domain-Containing Protein Gene Family in the Silkworm, Bombyx mori.
Int J Genomics
PUBLISHED: 01-24-2014
Show Abstract
Hide Abstract
The BTB domain is a conserved protein-protein interaction motif. In this study, we identified 56 BTB domain-containing protein genes in the silkworm, in addition to 46 in the honey bee, 55 in the red flour beetle, and 53 in the monarch butterfly. Silkworm BTB protein genes were classified into nine subfamilies according to their domain architecture, and most of them could be mapped on the different chromosomes. Phylogenetic analysis suggests that silkworm BTB protein genes may have undergone a duplication event in three subfamilies: BTB-BACK-Kelch, BTB-BACK-PHR, and BTB-FLYWCH. Comparative analysis demonstrated that the orthologs of each of 13 BTB protein genes present a rigorous orthologous relationship in the silkworm and other surveyed insects, indicating conserved functions of these genes during insect evolution. Furthermore, several silkworm BTB protein genes exhibited sex-specific expression in larval tissues or at different stages during metamorphosis. These findings not only contribute to a better understanding of the evolution of insect BTB protein gene families but also provide a basis for further investigation of the functions of BTB protein genes in the silkworm.
Related JoVE Video
Theoretical investigation on the crystal structures and electron transport properties of several nitrogen-rich pentacene derivatives.
J Mol Model
PUBLISHED: 01-24-2014
Show Abstract
Hide Abstract
Exploring and synthesizing new simple n-channel organic semiconductor materials with large electron mobility and high air stability have remained a major challenge and hot issue in the field of organic electronics. In the current work, the electron transport properties of four novel nitrogen-rich pentacene derivatives (PBD1, PBD2, PBD3, and PBD4) with two cyano groups as potential n-channel OFET materials have been investigated at the molecular and crystal levels by means of density functional theory (DFT) calculations coupled with the prediction of crystal structures and the incoherent charge-hopping model. Calculations reveal that the studied compounds, which possess low-lying frontier molecular energy levels, large ionization potentials and electron affinities, are very stable exposed to air. Based on predicted crystal structures, the average electron mobility at room temperature (T?=?300 K) for PBD1, PBD2, PBD3, and PBD4 is predicted to be as high as 0.950, 0.558, 0.518, and 1.052 cm²·V?¹·s?¹, which indicate that these four compounds are more than likely to be promising candidates as n-type OFET materials under favorable device conditions. However, this claim needs experimental verification. In addition, the angular-dependent simulation for electron mobility shows that the electron transport is remarkably anisotropic in these molecular crystals and the maximum ?(e) appears along the crystal axis direction since molecules along this direction exhibit the close face-to-face stacking arrangement with short interplanar distances (~3.6-4.0 Å), which induces large electronic couplings.
Related JoVE Video
From molecules to materials: computational design of N-containing porous aromatic frameworks for CO2 capture.
Chemphyschem
PUBLISHED: 01-22-2014
Show Abstract
Hide Abstract
Porous aromatic frameworks (PAFs) are novel materials with diamond topology. With the aim of enhancing their CO(2) capture and storage capacity and investigating the effect of nitrogen and/or -COOH decorations on CO(2) adsorption in PAFs, a series of N-containing PAFs were designed based on ab initio results. The interaction energies (E(int)) between CO(2) and each six-membered ring were calculated at the B2PLYP-D2/def2-TZVPP level, then the six-membered rings with high CO(2) -binding affinity were selected and used in the PAFs. To explore the performance of the designed PAFs, the CO(2) uptake, selectivity of CO(2) over CH(4), H(2), and N(2), and the E(int) value of CO(2) in PAFs were investigated by using grand canonical Monte Carlo (GCMC) simulations and ab initio calculations. This work shows that pyridine with one nitrogen atom can provide a strong physisorption site for CO(2), whereas more nitrogen atoms in heterocycles will reduce the interaction, especially at relatively low pressure. PAFs with -COOH groups show high CO(2) capacity. Our work provides an efficient way to understand the adsorption mechanism and a supplemental approach to experimental work.
Related JoVE Video
Mitochondrial genome of the Anas crecca (Anatidae: Anas).
Mitochondrial DNA
PUBLISHED: 01-21-2014
Show Abstract
Hide Abstract
Abstract Mitochondrial DNA plays an important role in living organisms, and has been used as a powerful molecular marker in various evolutionary studies. In this study, we determined the complete mitochondrial genome of Anas crecca (16,601?bp in length). Similar to the typical mtDNA of vertebrates, it contained 37 genes (13 protein-coding genes, 2 rRNA genes and 22 tRNA genes) and a non-coding region (D-loop). Overall base composition of the complete mitochondrial DNA was 29.05% A, 22.35% T, 32.64% C and 15.96% G.
Related JoVE Video
Dietary nicotinic acid supplementation ameliorates chronic alcohol-induced fatty liver in rats.
Alcohol. Clin. Exp. Res.
PUBLISHED: 01-18-2014
Show Abstract
Hide Abstract
Alcohol abuse frequently causes niacin deficiency in association with the development of alcoholic liver disease. The objective of the present study was to determine whether dietary nicotinic acid (NA) deficiency exaggerates and whether dietary NA supplementation alleviates alcohol-induced fatty liver.
Related JoVE Video
A new insight into the 5-carboxycytosine and 5-formylcytosine under typical bisulfite conditions: a deamination mechanism study.
Phys Chem Chem Phys
PUBLISHED: 01-14-2014
Show Abstract
Hide Abstract
5-Methylcytosine (5-MeCyt) can be converted to 5-hydroxymethylcytosine (5-hmCyt) in mammalian DNA by the ten-eleven translocation enzymes. The conventional bisulfite sequencing cannot discriminate 5-hmCyt from 5-MeCyt, whereas the oxidation products of 5-hmCyt, 5-carboxycytosine (5-caCyt) and 5-formylcytosine (5-fCyt) enable them to be identified in bisulfite sequencing. This mechanism likely involves the decarboxylation of 5-caCyt and deformylation of 5-fCyt to cytosine (Cyt) before deamination. Another possibility could be a direct bisulfite-induced deamination reaction followed by decarboxylation and deformylation. Here the HSO3(-)-induced direct hydrolytic deamination of 5-caCytN3(+)-SO3(-) (paths A and B) and 5-O(+)fCytN3(+)-SO3(-) (paths C and D) has been explored at the MP2/6-311++G(3df,3pd)//B3LYP/6-311++G(d,p) level. The activation free energy (?G(s?) = 54.16 kJ mol(-1)) of the direct hydrolytic deamination of 5-caCytN3(+)-SO3(-) path A is much lower than the ?G(s?) of CytN3(+)-SO3(-) (100.91 kJ mol(-1)) under bisulfite conditions, implying that 5-caCyt may firstly involve a process of deamination. Meanwhile, the ?G(s?) (103.84 kJ mol(-1)) of the HSO3(-)-induced direct hydrolytic deamination of 5-O(+)fCytN3(+)-SO3(-) path C is in close proximity to our previous theoretical data for CytN3(+)-SO3(-), indicating that the deamination of 5-fCyt is also likely to occur in the presence of bisulfite. Meanwhile, the HSO3(-)-induced direct hydrolytic deamination of 5-caCytN3(+)-SO3(-) path A and 5-O(+)fCytN3(+)-SO3(-) path C is represented and has been further explored in the presence of one and two water molecules. The results show that both in the gas and aqueous phases, the participation of one and two water molecules makes the HSO3(-)-induced direct hydrolytic deamination of 5-caCytN3(+)-SO3(-) path A unfavorable, whereas the contribution of one and two water molecules facilitates the HSO3(-)-induced direct hydrolytic deamination of 5-O(+)fCytN3(+)-SO3(-) path C.
Related JoVE Video
GRK3 is essential for metastatic cells and promotes prostate tumor progression.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 01-13-2014
Show Abstract
Hide Abstract
The biochemical mechanisms that regulate the process of cancer metastasis are still poorly understood. Because kinases, and the signaling pathways they comprise, play key roles in regulation of many cellular processes, we used an unbiased RNAi in vitro screen and a focused cDNA in vivo screen against human kinases to identify those with previously undocumented roles in metastasis. We discovered that G-protein-coupled receptor kinase 3 (GRK3; or ?-adrenergic receptor kinase 2) was not only necessary for survival and proliferation of metastatic cells, but also sufficient to promote primary prostate tumor growth and metastasis upon exogenous expression in poorly metastatic cells in mouse xenograft models. Mechanistically, we found that GRK3 stimulated angiogenesis, at least in part through down-regulation of thrombospondin-1 and plasminogen activator inhibitor type 2. Furthermore, GRK3 was found to be overexpressed in human prostate cancers, especially in metastatic tumors. Taken together, these data suggest that GRK3 plays an important role in prostate cancer progression and metastasis.
Related JoVE Video
CD4 T cell defects in the aged: causes, consequences and strategies to circumvent.
Exp. Gerontol.
PUBLISHED: 01-02-2014
Show Abstract
Hide Abstract
Aging leads to reduced immunity, especially adaptive responses. A key deficiency is the poor ability to mount robust antibody response. Although intrinsic alterations in B cells with age are in part responsible, impaired CD4 T cell help makes a major contribution to the poor antibody response. Other CD4 effector responses and memory generation are also impaired. We find delayed and reduced development of CD4 T follicular help (Tfh) cells in aged mice in response to influenza infection with reduction of long-lived plasma cells. When we examine CD4 subsets we also find a shift towards Th1 and cytotoxic CD4 (ThCTL) responses. We summarize strategies to circumvent the CD4 T cell defect in aged, including adjuvants and proinflammatory cytokines. We find that we can strongly enhance responses of aged naïve CD4 T cells by using Toll-like receptor (TLR) activated dendritic cells (DC) as APC in vivo and that this leads to improved germinal center B cells and IgG antibody responses. The enhanced response of aged naïve CD4 T cells is dependent on IL-6 produced by the DC.
Related JoVE Video
Neural Network Cascade Optimizes MicroRNA Biomarker Selection for Nasopharyngeal Cancer Prognosis.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
MicroRNAs (miRNAs) have been shown to be promising biomarkers in predicting cancer prognosis. However, inappropriate or poorly optimized processing and modeling of miRNA expression data can negatively affect prediction performance. Here, we propose a holistic solution for miRNA biomarker selection and prediction model building. This work introduces the use of a neural network cascade, a cascaded constitution of small artificial neural network units, for evaluating miRNA expression and patient outcome. A miRNA microarray dataset of nasopharyngeal carcinoma was retrieved from Gene Expression Omnibus to illustrate the methodology. Results indicated a nonlinear relationship between miRNA expression and patient death risk, implying that direct comparison of expression values is inappropriate. However, this method performs transformation of miRNA expression values into a miRNA score, which linearly measures death risk. Spearman correlation was calculated between miRNA scores and survival status for each miRNA. Finally, a nine-miRNA signature was optimized to predict death risk after nasopharyngeal carcinoma by establishing a neural network cascade consisting of 13 artificial neural network units. Area under the ROC was 0.951 for the internal validation set and had a prediction accuracy of 83% for the external validation set. In particular, the established neural network cascade was found to have strong immunity against noise interference that disturbs miRNA expression values. This study provides an efficient and easy-to-use method that aims to maximize clinical application of miRNAs in prognostic risk assessment of patients with cancer.
Related JoVE Video
Nuclear import of transcription factor BR-C is mediated by its interaction with RACK1.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
The transcription factor Broad Complex (BR-C) is an early ecdysone response gene in insects and contains two types of domains: two zinc finger domains for the activation of gene transcription and a Bric-a-brac/Tramtrack/Broad complex (BTB) domain for protein-protein interaction. Although the mechanism of zinc finger-mediated gene transcription is well studied, the partners interacting with the BTB domain of BR-C has not been elucidated until now. Here, we performed a yeast two-hybrid screen using the BTB domain of silkworm BR-C as bait and identified the receptor for activated C-kinase 1 (RACK1), a scaffolding/anchoring protein, as the novel partner capable of interacting with BR-C. The interaction between BR-C and RACK1 was further confirmed by far-western blotting and pull-down assays. Importantly, the disruption of this interaction, via RNAi against the endogenous RACK1 gene or deletion of the BTB domain, abolished the nuclear import of BR-C in BmN4 cells. In addition, RNAi against the endogenous PKC gene as well as phosphorylation-deficient mutation of the predicted PKC phosphorylation sites at either Ser373 or Thr406 in BR-C phenocopied RACK1 RNAi and altered the nuclear localization of BR-C. However, when BTB domain was deleted, phosphorylation mimics of either Ser373 or Thr406 had no effect on the nuclear import of BR-C. Moreover, mutating the PKC phosphorylation sites at Ser373 and Thr406 or deleting the BTB domain significantly decreased the transcriptional activation of a BR-C target gene. Given that RACK1 is necessary for recruiting PKC to close and phosphorylate target proteins, we suggest that the PKC-mediated phosphorylation and nuclear import of BR-C is determined by its interaction with RACK1. This novel finding will be helpful for further deciphering the mechanism underlying the role of BR-C proteins during insect development.
Related JoVE Video
Flos Puerariae extract prevents myocardial apoptosis via attenuation oxidative stress in streptozotocin-induced diabetic mice.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Diabetic cardiomyopathy (DCM) suggests a direct cellular insult to myocardium. Apoptosis is considered as one of the hallmarks of DCM. Oxidative stress plays a key role in the pathogenesis of DCM. In this study, we explored the prevention of myocardial apoptosis by crude extract from Flos Puerariae (FPE) in experimental diabetic mice.
Related JoVE Video
The use of functional chemical-protein associations to identify multi-pathway renoprotectants.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Typically, most nephropathies can be categorized as complex human diseases in which the cumulative effect of multiple minor genes, combined with environmental and lifestyle factors, determines the disease phenotype. Thus, multi-target drugs would be more likely to facilitate comprehensive renoprotection than single-target agents. In this study, functional chemical-protein association analysis was performed to retrieve multi-target drugs of high pathway wideness from the STITCH 3.1 database. Pathway wideness of a drug evaluated the efficiency of regulation of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways in quantity. We identified nine experimentally validated renoprotectants that exerted remarkable impact on KEGG pathways by targeting a limited number of proteins. We selected curcumin as an illustrative compound to display the advantage of multi-pathway drugs on renoprotection. We compared curcumin with hemin, an agonist of heme oxygenase-1 (HO-1), which significantly affects only one KEGG pathway, porphyrin and chlorophyll metabolism (adjusted p?=?1.5×10-5). At the same concentration (10 µM), both curcumin and hemin equivalently mitigated oxidative stress in H2O2-treated glomerular mesangial cells. The benefit of using hemin was derived from its agonistic effect on HO-1, providing relief from oxidative stress. Selective inhibition of HO-1 completely blocked the action of hemin but not that of curcumin, suggesting simultaneous multi-pathway intervention by curcumin. Curcumin also increased cellular autophagy levels, enhancing its protective effect; however, hemin had no effects. Based on the fact that the dysregulation of multiple pathways is implicated in the etiology of complex diseases, we proposed a feasible method for identifying multi-pathway drugs from compounds with validated targets. Our efforts will help identify multi-pathway agents capable of providing comprehensive protection against renal injuries.
Related JoVE Video
Identification and characterization of MT-1X as a novel FHL3-binding partner.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Four and a half LIM domain protein 3 (FHL3) is a member of the FHL protein family that plays roles in the regulation of cell survival, cell adhesion and signal transduction. However, the mechanism of action for FHL3 is not yet clear. The aim of present study was to identify novel binding partner of FHL3 and to explore the underlying mechanism. With the use of yeast two-hybrid screening system, FHL3 was used as the bait to screen human fetal hepatic cDNA library for interacting proteins. Methionine-1X was identified as a novel FHL3 binding partner. The interaction between FHL3 and the full length MT-1X was further confirmed by yeast two-hybrid assay, co-immunoprecipitation and GST pull-down assays. Furthermore,the result demonstrated that MT-1X knockdown promoted the FHL3-induced inhibitory effect on HepG2 cells by regulating FHL3-mediated Smad signaling and involving in the modulation the expression of G2/M phase-related proteins through interaction with FHL3. These findings suggest that functional interactions between FHL3 and MT-1X may provide some clues to the mechanisms of FHL3-regulated cell proliferation.
Related JoVE Video
Group 3 metal stilbene complexes: synthesis, reactivity, and electronic structure studies.
Chem. Commun. (Camb.)
PUBLISHED: 12-17-2013
Show Abstract
Hide Abstract
Group 3 metal (E)-stilbene complexes supported by a ferrocene diamide ligand were synthesized and characterized. Reactivity studies showed that they behave similar to analogous naphthalene complexes. Experimental and computational results indicated that the double bond was reduced and not a phenyl ring, in contrast to a previously reported uranium (E)-stilbene complex.
Related JoVE Video
Effects of Rosuvastatin vs. Simvastatin/ezetimibe on Arterial Wall Stiffness in Patients with Coronary Artery Disease.
Intern. Med.
PUBLISHED: 12-17-2013
Show Abstract
Hide Abstract
Objective Statins prevent cardiovascular events in patients with coronary artery disease (CAD). However, there is little information regarding the vascular effects of statins on arterial wall stiffness in CAD patients. Methods A total of 36 patients were randomly assigned to receive rosuvastatin (10 mg per day) or simvastatin/ezetimibe (10/10 mg per day) for eight weeks. The aim of the present study was to determine the effects of rosuvastatin or simvastatin/ezetimibe on arterial wall stiffness measured according to the brachial and ankle pulse wave velocity (baPWV) in CAD patients. Results Both treatments significantly improved the levels of total cholesterol (TC), triglycerides (TGs), low-density lipoprotein cholesterol (LDL-C) and high-sensitivity C-reactive protein (hs-CRP) (p<0.05). The ROCK activity and baPWV were significantly improved in the rosuvastatin group compared with that observed in the simvastatin/ezetimibe group (p<0.05). The changes in baPWV were significantly correlated with the changes in the ROCK activity (r=0.488, p<0.01), but not with the changes in the lipid profile or the hs-CRP level. Conclusion Compared with simvastatin/ezetimibe (10/10 mg), rosuvastatin (10 mg) appears to more effectively improve arterial wall stiffness that may be mediated by modulation of the ROCK activity.
Related JoVE Video
Genome Sequence of Border Disease Virus Strain JSLS12-01, Isolated from Sheep in China.
Genome Announc
PUBLISHED: 11-09-2013
Show Abstract
Hide Abstract
Border disease virus (BDV) is a recognized virus in the genus Pestivirus and causes border disease (BD) in sheep and goats. Here, a novel BDV strain, JSLS12-01, was identified from sheep in Jiangsu Province, China. The complete coding sequence (CDS) was finished, which provides a better understanding of the molecular evolution of BDV isolates.
Related JoVE Video
Anterior versus posterior approach for four-level cervical spondylotic myelopathy.
Orthopedics
PUBLISHED: 11-09-2013
Show Abstract
Hide Abstract
The purpose of this study was to compare the results of 2 surgical strategies for 4-level cervical spondylotic myelopathy: a hybrid procedure using anterior cervical diskectomy and fusion (ACDF) combined with segmental corpectomy versus posterior laminectomy and fixation. Between 2002 and 2010, fifty-one patients with consecutive 4-level cervical spondylotic myelopathy were treated surgically, with 27 patients undergoing the hybrid procedure and 24 undergoing posterior laminectomy and fixation. Radiologic data were compared between the 2 groups, including cervical curvature and cervical range of motion (ROM) in the sagittal plane. Pre- and postoperative neurological status was evaluated using the Japanese Orthopaedic Association (JOA) scoring system and the Nurick grading system. Mean ROM at last follow-up was not significantly different between the 2 groups (P>.05). In the hybrid group, mean JOA score and Nurick grade improved from 9.6±1.4 and 2.74±0.45 respectively, preoperatively, to 13.9±1.3 and 0.86±0.38 respectively, postoperatively. In the fixation group, mean JOA score and Nurick grade improved from 9.4±1.2 and 2.81±0.42 respectively, preoperatively, to 13.1±1.5 and 1.32±0.36 respectively, postoperatively. The JOA scores and Nurick grades at last follow-up were significantly different between the 2 groups (P<.05). In patients with preoperative cervical kyphosis, preoperative JOA score and Nurick grade were not significantly different between the 2 groups (P>.05); however, JOA scores and Nurick grades at last follow-up showed better improvement in the hybrid group than in the fixation group (P<.01). In patients with preoperative cervical lordosis, the preoperative and last follow-up JOA score and Nurick grade were not significantly different between the 2 groups (P>.05).
Related JoVE Video
Effect of Chinese traditional herb Epimedium grandiflorum C. Morren and its extract Icariin on osteoarthritis via suppressing NF-kappaB pathway.
Indian J. Exp. Biol.
PUBLISHED: 11-08-2013
Show Abstract
Hide Abstract
Osteoarthritis (OA), which is also called degenerative arthritis, is the leading cause of disabilities in the old people. The Chinese traditional herb Epimedium grandiflorum had long been found to attenuate osteoarthritis process, but the detailed mechanism was not clear. To study the mechanisms of E. grandiflorum in the treatment of osteoarthritis, rabbit osteoarthritis model combined with D-galactose was used. After different treatments for 10 weeks, cartilage sections were analyzed by immunohistochemistry for uPA, uPAR and PAI expression level. E. grandiflorum could significantly attenuate OA condition and decrease uPA, uPAR and PAI expression. The extract of E. grandiflorum, icariin also had a similar effect when compared with E. grandiflorum treatment alone. Rabbit chondrocytes were further isolated to be stimulated by TNFalpha combined with different reagents treatment. Here, icariin treatment significantly reduced nuclear factor kappa B NF-kappaB (P65) activity, decreased uPA expression level and increased Ikappabetaalpha protein level. The results indicated that E. grandiflorum and its extract icariin could attenuate OA condition, reduce the expression of uPA and uPAR and increase PAI in experimental rabbit model and this effect may be conducted by suppressing NF-kappaB activity by increasing IkappaBalpha level.
Related JoVE Video
New phenanthrene glycosides from Dioscorea opposita.
J Asian Nat Prod Res
PUBLISHED: 10-29-2013
Show Abstract
Hide Abstract
Two new phenanthrene glycosides, dioscopposide A and dioscopposide B (1 and 2), were isolated from the rhizomes of Dioscorea opposita. Their structures were determined primarily on the basis of 1D and 2D NMR techniques, MS studies, and chemical methods. All the isolates were evaluated for their inhibitory effects on the lipopolysaccharide-induced nitric oxide production using murine macrophage RAW 264.7 cells. The IC50 values of dioscopposide A and dioscopposide B were 5.8 and 7.2 ?M, respectively.
Related JoVE Video
Bioinertness and fracture toughness evaluation of the monoclinic zirconia surface film of Oxinium™ femoral head by Raman and cathodoluminescence spectroscopy.
J Mech Behav Biomed Mater
PUBLISHED: 10-11-2013
Show Abstract
Hide Abstract
Raman and cathodoluminescence spectroscopic methods were employed for clarifying important stoichiometric and mechanical properties so far missing in the specification of the physical origin of the structural behavior of Oxinium™ femoral head components. Spectroscopy proved helpful in rationalizing the actual physical and chemical reasons behind the mechanical integrity of the ceramic-film/metal-substrate interface, which is responsible for both the good adherence and the surface durability reported in prosthetic applications of Oxinium™ components. Raman spectroscopy coupled with the crack opening displacement (COD) method was used to evaluate the intrinsic fracture toughness of the surface oxide film. In addition, cathodoluminescence spectroscopy provided new evidences on both the oxygen vacancy gradient developed during the metal-oxidation manufacturing process and the bioinertness of Oxinium™ femoral components.
Related JoVE Video
Coordination environment evolution of Eu3+ during the dehydration and re-crystallization processes of Sm(1-x)Eu(x)[B9O13(OH)4]·H2O by photoluminescent characteristics.
Dalton Trans
PUBLISHED: 09-25-2013
Show Abstract
Hide Abstract
There are limited photoluminescence (PL) studies for rare earth borates with crystalline water molecules, which are usually supposed to have low PL efficiency because the vibrations of H2O or -OH may lead to emission quenching. We investigated the PL properties of Sm(1-x)Eu(x)[B9O13(OH)4]·H2O (x = 0-1.00) and their dehydrated products ?-Sm(1-x)Eu(x)B5O9. There is no quenching effect in those studied polyborates because the large borate ionic groups isolate the Eu(3+) activators very well. Sm(3+) and Eu(3+) are basically separated luminescent activators. Comparatively, Sm(3+) shows a very small emission intensity, which can be almost ignored, therefore our interest is focused on the Eu(3+) luminescence. By TG-DSC and powder XRD experiments, we defined three weight-loss steps for Eu[B9O13(OH)4]·H2O and a re-crystallization process to ?-EuB5O9, during which luminescent spectra of Eu(3+) are recorded. It shows an interesting variety and therefore is a good medium to understand the coordination environment evolution of Eu(3+), even for the intermediate amorphous phase. In fact, the coordination symmetry of Eu(3+) in the amorphous state is the lowest. The high efficiency of the f-f transitions and large R/O value (3.8) imply this amorphous phase is potentially a good red-emitting UV-LED phosphor. Anhydrous ?-EuB5O9 shows the highest luminescent efficiency excited by Eu(3+) CT transition. In addition, ?-Sm(1-x)Eu(x)B5O9 was synthesized by a sol-gel method directly for the first time, and ?-EuB5O9 shows superior PL properties due to its better crystallinity. A lot of hydrated polyborates with crystalline water molecules remain unexplored and our study shows their potential as good phosphors.
Related JoVE Video
ETS-1-mediated transcriptional up-regulation of CD44 is required for sphingosine-1-phosphate receptor subtype 3-stimulated chemotaxis.
J. Biol. Chem.
PUBLISHED: 09-24-2013
Show Abstract
Hide Abstract
Sphingosine-1-phosphate (S1P)-regulated chemotaxis plays critical roles in various physiological and pathophysiological conditions. S1P-regulated chemotaxis is mediated by the S1P family of G-protein-coupled receptors. However, molecular details of the S1P-regulated chemotaxis are incompletely understood. Cultured human lung adenocarcinoma cell lines abundantly express S1P receptor subtype 3 (S1P3), thus providing a tractable in vitro system to characterize molecular mechanism(s) underlying the S1P3 receptor-regulated chemotactic response. S1P treatment enhances CD44 expression and induces membrane localization of CD44 polypeptides via the S1P3/Rho kinase (ROCK) signaling pathway. Knockdown of CD44 completely diminishes the S1P-stimulated chemotaxis. Promoter analysis suggests that the CD44 promoter contains binding sites of the ETS-1 (v-ets erythroblastosis virus E26 oncogene homolog 1) transcriptional factor. ChIP assay confirms that S1P treatment stimulates the binding of ETS-1 to the CD44 promoter region. Moreover, S1P induces the expression and nuclear translocation of ETS-1. Knockdown of S1P3 or inhibition of ROCK abrogates the S1P-induced ETS-1 expression. Furthermore, knockdown of ETS-1 inhibits the S1P-induced CD44 expression and cell migration. In addition, we showed that S1P3/ROCK signaling up-regulates ETS-1 via the activity of JNK. Collectively, we characterized a novel signaling axis, i.e., ROCK-JNK-ETS-1-CD44 pathway, which plays an essential role in the S1P3-regulated chemotactic response.
Related JoVE Video
Mitochondrial genome of the Anas acuta (Anatidae: Anas).
Mitochondrial DNA
PUBLISHED: 09-20-2013
Show Abstract
Hide Abstract
Abstract The Northern Pintail (Anas acuta) is a common large duck with widely geographic distribution. In this study, the complete mitochondrial genome of A. acuta (16,599?bp in length) was been analyzed for building the database. Similar to the typical mtDNA of vertebrates, it contained 37 genes (13 protein-coding genes, 2 rRNA genes and 22 tRNA genes) and a non-coding region (D-loop). All the genes in A. acuta were distributed on the H-strand, except for the ND6 subunit gene and 10 tRNA genes which were encoded on the L-strand.
Related JoVE Video
Nondestructive inspection of phase transformation in zirconia-containing hip joints by confocal Raman spectroscopy.
J Biomed Opt
PUBLISHED: 09-17-2013
Show Abstract
Hide Abstract
ABSTRACT. Environmental metastability of zirconia (ZrO2) ceramic in the human body [represented by a tetragonal-to-monoclinic (t?m) phase transformation] takes place on the surface of the artificial joint and proceeds with time toward its interior. Its quantitative characterization is mandatory for the safety of joint implants and consists of the assessment of the in-depth monoclinic profile fraction as compared to that of the initially untransformed material. We attempt to fully establish a characterization protocol and present two different nondestructive approaches for resolving highly graded phase-transformation profiles along the hip-joint subsurface by confocal Raman microprobe technique. A series of partially transformed tetragonal zirconia polycrystal and zirconia-toughened alumina ceramics are used as screening samples. Probe biases could be eliminated and the real transformation profiles retrieved through a deconvolution procedure of Raman experimental data collected as a function of pinhole aperture and focal depth, respectively. Confirmation of the confocal assessments was made by a destructive cross-sectional inspection by both laser optical microscope and Raman spectral line scans. This study unveils for the first time the real quantitative amount of surface phase-transformation fractions and the related subsurface profiles in zirconia-based retrieved medical samples.
Related JoVE Video
The complete mitochondrial genome of Anas poecilorhyncha (Anatidae: Anas).
Mitochondrial DNA
PUBLISHED: 09-12-2013
Show Abstract
Hide Abstract
Abstract The mitochondrial genome of Anas poecilorhyncha (Anatidae: Anas) is a circular molecule of 16,608?bp in length, containing 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 control region (D-loop). Overall base composition of the complete mitochondrial DNA was 29.17% A, 22.21% T, 32.81% C and 15.81% G.
Related JoVE Video
SIRT5: a safeguard against oxidative stress-induced apoptosis in cardiomyocytes.
Cell. Physiol. Biochem.
PUBLISHED: 09-03-2013
Show Abstract
Hide Abstract
SIRT5 is located in the mitochondria, and plays a crucial role in the regulation of metabolic process and cellular apoptosis. Cardiomyocytes are abundant in mitochondria. However, the role of SIRT5 in oxidative stress-induced apoptosis is still unknown in cardiomyocytes.
Related JoVE Video
[Non-thoracoscopic and thoracoscopic modified Nuss procedure for correction of pectus excavatum].
Zhong Nan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 08-29-2013
Show Abstract
Hide Abstract
To summarize the curative effect, safety and experience of non-thoracoscopic modified Nuss procedure for correction of pectus excavatum (PE).
Related JoVE Video
Multiscale simulation of pollution gases adsorption in porous organic cage CC3.
J Comput Chem
PUBLISHED: 08-24-2013
Show Abstract
Hide Abstract
A general multiscale simulation procedure is proposed to accurately predict the uptakes of pollution gases such as CO2 , SO2 , H2 S, and CO in one of the most investigated porous organic cages CC3 by using a sophisticated force field vdW3 fitted by double hybrid functional (B2PLYP) with a dispersion correction (D3) separately for gas-gas and CC3-gas interactions. The fitted vdW3 was used in grand canonical Monte Carlo simulations. Good comparison with the coupled cluster single and double excitation and the perturbative triples (CCSD(T))/complete basis set (CBS) limit interaction energies make the B2PLYP-D3 results reliable for our purpose. The good agreement of simulated CO2 loading with experimental one and the low deviation in the fitting procedure for H2 S and CO make our approach available in predicting gases in novel porous materials. © 2013 Wiley Periodicals, Inc.
Related JoVE Video
Results of a bone splint technique for the treatment of lower limb deformities in children with type I osteogenesis imperfecta.
Indian J Orthop
PUBLISHED: 08-21-2013
Show Abstract
Hide Abstract
Children with osteogenesis imperfecta (OI) can suffer from frequent fractures and limb deformities, resulting in impaired ambulation. Osteopenia and thin cortices complicate orthopedic treatment in this group. This study evaluates the clinical results of a bone splint technique for the treatment of lower limb deformities in children with type I OI. The technique consists of internal plating combined with cortical strut allograft fixation.
Related JoVE Video
SIRT4 prevents hypoxia-induced apoptosis in H9c2 cardiomyoblast cells.
Cell. Physiol. Biochem.
PUBLISHED: 08-18-2013
Show Abstract
Hide Abstract
Apoptosis plays a critical role in cardiomyocyte loss during ischaemic heart injury. A detailed understanding of the mechanism involved has a substantial impact on the optimization and development of treatment strategies. Here, we report that the expression of SIRT4, a mitochondrial sirtuin, is markedly down-regulated in hypoxia-induced apoptosis of H9c2 cardiomyoblast cells.
Related JoVE Video
Metal-Induced Isomerization Yields an Intracellular Chelator that Disrupts Bacterial Iron Homeostasis.
Chem. Biol.
PUBLISHED: 08-15-2013
Show Abstract
Hide Abstract
The dwindling supply of antibiotics that remain effective against drug-resistant bacterial pathogens has precipitated efforts to identify new compounds that inhibit bacterial growth using untapped mechanisms of action. Here, we report both (1) a high-throughput screening methodology designed to discover chemical perturbants of the essential, yet unexploited, process of bacterial iron homeostasis, and (2) our findings from a small-molecule screen of more than 30,000 diverse small molecules that led to the identification and characterization of two spiro-indoline-thiadiazoles that disrupt iron homeostasis in bacteria. We show that these compounds are intracellular chelators with the capacity to exist in two isomeric states. Notably, these spiroheterocyles undergo a transition to an open merocyanine chelating form with antibacterial activity that is specifically induced in the presence of its transition-metal target.
Related JoVE Video

What is Visualize?

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

How does it work?

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

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

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