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.
Analysis of all-optical temporal integrator employing phased-shifted DFB-SOA.
Opt Express
PUBLISHED: 11-18-2014
Show Abstract
Hide Abstract
All-optical temporal integrator using phase-shifted distributed-feedback semiconductor optical amplifier (DFB-SOA) is investigated. The influences of system parameters on its energy transmittance and integration error are explored in detail. The numerical analysis shows that, enhanced energy transmittance and integration time window can be simultaneously achieved by increased injected current in the vicinity of lasing threshold. We find that the range of input pulse-width with lower integration error is highly sensitive to the injected optical power, due to gain saturation and induced detuning deviation mechanism. The initial frequency detuning should also be carefully chosen to suppress the integration deviation with ideal waveform output.
Related JoVE Video
Validation of a Next-Generation-Sequencing Cancer Panel for Use in the Clinical Laboratory.
Arch. Pathol. Lab. Med.
PUBLISHED: 10-31-2014
Show Abstract
Hide Abstract
Context .- Next-generation sequencing allows for high-throughput processing and sensitive variant detection in multiple genes from small samples. For many diseases, including cancer, a comprehensive mutational profile of a targeted list of genes can be used to simultaneously inform patient care, establish eligibility for ongoing clinical trials, and further research. Objective .- To validate a pan-cancer, next-generation-sequencing assay for use in the clinical laboratory. Design .- DNA was extracted from 68 clinical specimens (formalin-fixed, paraffin-embedded; fine-needle aspirates; peripheral blood; or bone marrow) and 5 normal controls. Sixty-four DNA samples (94%; 64 of 68) were successfully processed with the TruSeq Amplicon Cancer Panel (Illumina Inc, San Diego, California) and sequenced in 4 sequencing runs. The data were analyzed at 4 different filter settings for sequencing coverage and variant frequency cutoff. Results .- Libraries created from 40 specimens could be successfully sequenced in a single run and still yield sufficient coverage for robust data analysis of individual samples. Sensitivity for mutation detection down to 5% was demonstrated using dilutions of clinical specimens and control samples. The test was highly repeatable and reproducible and showed 100% concordance with clinically validated Sanger sequencing results. Comparison to an alternate next-generation sequencing technology was performed by also processing 9 of the specimens with the AmpliSeq Cancer Hotspot Panel (version 2; Life Technologies, Grand Island, New York). Thirty of the 31 (97%) TruSeqdetected variants covered by the designs of both panels were confirmed. Conclusion .- A sensitive, high-throughput, pan-cancer mutation panel for sequencing of cancer hot-spot mutations in 42 genes was validated for routine use in clinical testing.
Related JoVE Video
Prognostic Significance of the Mucin Component in Stage III Rectal Carcinoma Patients.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-24-2014
Show Abstract
Hide Abstract
Although mucinous adenocarcinoma has been recognized for a long time, whether it is associated with a poorer prognosis in colorectal cancer patients is still controversial. Many studies put emphasis on mucinous adenocarcinoma containing mucin component ?50%. Only a few studies have analyzed cases with a mucin component <50%.
Related JoVE Video
The Pin1 gene polymorphism and the susceptibility of oral squamous cell carcinoma in East China.
Cancer Biomark
PUBLISHED: 10-23-2014
Show Abstract
Hide Abstract
Pin1 is a peptidylprolyl isomerase that specifically recognizes phosphorylated Pro-directed Ser/Thr (pSer/Thr-Pro) peptide sequences. Genetic variants in the Pin1 gene may alter protein function and cancer risk. In this study, we genotyped the two common promoter polymorphisms -842G/C (rs2233678) and -667T/C (rs2233679) in two independent hospital-based case-control studies conducted in Eastern Chinese populations, including 209 patients with oral squamous cell carcinoma and 444 cancer-free controls. We found -667TT heterozygotes had a significantly increased risk of oral squamous cell carcinoma (P=0.028, OR=1.66, 95%CI=1.02-2.69). However, there was no risk significant associated with the -842G/C polymorphism. Further large population-based studies are needed to confirm these results.
Related JoVE Video
Changing reaction pathways of the dimerization of 2-formylcinnamates by N-heterocyclic carbene/lewis Acid cooperative catalysis: an unusual cleavage of the carbon-carbon bond.
Org. Lett.
PUBLISHED: 10-20-2014
Show Abstract
Hide Abstract
Catalyzed by a triazole carbene, the dimerization of 2-formylcinnamates underwent benzoin condensation followed by intramolecular oxa-Michael addition to afford isochromeno[4,3-c]isochromene products. Under the catalysis of a combination of triazole carbene and Ti(OPr-i)4 catalysts, the dimerization reaction of 2-formylcinnamates proceeded through a completely different route to furnish the formation of isochromenone derivatives with the elimination of an acetate moiety.
Related JoVE Video
Protective Effects of Akebia Saponin D Against Rotenone-Induced Hepatic Mitochondria Dysfunction.
J. Pharmacol. Sci.
PUBLISHED: 10-15-2014
Show Abstract
Hide Abstract
Akebia saponin D (ASD) is a typical bioactive triterpenoid saponin obtained from the rhizome of Dipsacus asper Wall. Previous studies have found that ASD has a hepatoprotective effect in a mouse model. The purpose of this paper was to explore the molecular mechanism of the hepatoprotective effects of ASD on BRL cells and isolated rat liver mitochondria. We investigated the effects of ASD on rotenone-induced toxicity in BRL cells. The results showed that ASD inhibited the accumulation of reactive oxidant species, ATP deficiency, and mitochondrial membrane potential dissipation; ameliorates mitochondrial respiratory dysfunction, and improved the activity of complex I in a concentration-dependent manner, indicating that ASD likely improved mitochondrial function. ASD suppressed rotenone-induced BRL cell apoptosis and increased Bcl-2/Bax ratio. These results suggest that ASD may exert hepatoprotective effects against rotenone-induced toxicity through mitochondria. This study supports our previous research that ASD possesses hepatoprotective activity in vivo and it is worthy of further study.
Related JoVE Video
Effects of surround suppression on response adaptation of V1 neurons to visual stimuli.
Zool. Res.
PUBLISHED: 10-10-2014
Show Abstract
Hide Abstract
The influence of intracortical inhibition on the response adaptation of visual cortical neurons remains in debate. To clarify this issue, in the present study the influence of surround suppression evoked through the local inhibitory interneurons on the adaptation effects of neurons in the primary visual cortex (V1) were observed. Moreover, the adaptations of V1 neurons to both the high-contrast visual stimuli presented in the classical receptive field (CRF) and to the costimulation presented in the CRF and the surrounding nonclassical receptive field (nCRF) were compared. The intensities of surround suppression were modulated with different sized grating stimuli. The results showed that the response adaptation of V1 neurons decreased significantly with the increase of surround suppression and this adaptation decrease was due to the reduction of the initial response of V1 neurons to visual stimuli. However, the plateau response during adaptation showed no significant changes. These findings indicate that the adaptation effects of V1 neurons may not be directly affected by surround suppression, but may be dynamically regulated by a negative feedback network and be finely adjusted by its initial spiking response to stimulus. This adaptive regulation is not only energy efficient for the central nervous system, but also beneficially acts to maintain the homeostasis of neuronal response to long-presenting visual signals.
Related JoVE Video
Interleukin-18 Synergism with Interleukin-2 in Cytotoxicity and NKG2D Expression of Human Natural Killer Cells.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-09-2014
Show Abstract
Hide Abstract
Natural killer (NK) cells play an important role in anti-tumor immunity. Interleukin (IL)-18 is an immunoregulatory cytokine that induces potent NK cell-dependent anti-tumor responses when administrated with other cytokines. In this study, we explored the effects of combining IL-18 and IL-2 on NK cytotoxicity as well as expression levels of the NK cell receptor NKG2D in vitro. Freshly isolated PBMCs were incubated for 48 h with IL-18 and IL-2, then CD107a expression on CD3-CD56+ NK cells was determined by three-colour flow cytometry to evaluate the cytotoxicity of NK cells against human erythroleukemia K562 cells and human colon carcinoma HT29 cells. Flow cytometric analysis was also employed to determine NKG2D expression on NK cells. The combined use of IL-18 and IL-2 significantly increased CD107a expression on NK cells compared with using IL-18 or IL-2 alone, suggesting that the combination of these two cytokines exerted synergistic enhancement of NK cytotoxicity. IL-18 also enhanced NKG2D expression on NK cells when administered with IL-2. In addition, blockade of NKG2D signaling with NKG2D-blocking antibody attenuated the up-regulatory effect of combining IL-18 and IL-2 on NK cytolysis. Our data revealed that IL-18 synergized with IL-2 to dramatically enhance the cytolytic activity of human NK cells in a NKG2D-dependent manner. The results appear encouraging for the use of combined IL-18 and IL-2 in tumor immunotherapy.
Related JoVE Video
[The subtle anatomical structures of normal nasal bone in MSCT image and forensic identification].
Fa Yi Xue Za Zhi
PUBLISHED: 10-03-2014
Show Abstract
Hide Abstract
To summarize the subtle anatomical structures of the normal nasal bone in multi-slice spiral CT (MSCT) image through the observation of the three-dimensional images.
Related JoVE Video
[Simulation of atmospheric temperature and moisture profiles retrieval from CrIS observations].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 10-02-2014
Show Abstract
Hide Abstract
In order to get higher vertical resolution atmosphere profile information, the present paper retrieves atmospheric temperature and moisture profiles from the Cross-track Infrared Sounder (CrIS) on the newly-launched Suomi National Polar-orbiting Partnership (Suomi NPP) and future Joint Polar Satellite System (JPSS) with a nonlinear Newton iteration method by using the profiles retrieved via statical regression method as the first guess, and the issue of channel selection is discussed. The retrieved profiles are compared with radiosonde observations, and National Centers for Environmental Prediction (NCEP) Global Data Assimilation System (GDAS) analyses show that the physical retrievals of temperature and moisture are in good agreement with the distributions from GDAS analysis fields and radiosonde observations, and have a notable improvements of the atmospheric profile retrieval accuracy as compared with the eigenvector regression algorithm. For pressures between 200 and 700 hPa the accuracy is of the order of 1 K for the temperature profile, and 20% for the relative humidity profile is consistent with the jacobian peaks of the selected channels.
Related JoVE Video
Comparison in efficacy between pure NOTES peritoneoscopy with small or large endoscope and laparoscopy.
J Dig Dis
PUBLISHED: 09-23-2014
Show Abstract
Hide Abstract
To evaluate the efficacy and systematic impact of different sized endoscopes for pure transgastric natural orifice transluminal endoscopic surgery (NOTES) peritoneoscopy relative to laparoscopy.
Related JoVE Video
Tumor suppressor role of protein 4.1B/DAL-1.
Cell. Mol. Life Sci.
PUBLISHED: 09-03-2014
Show Abstract
Hide Abstract
Protein 4.1B/DAL-1 is a membrane skeletal protein that belongs to the protein 4.1 family. Protein 4.1B/DAL-1 is localized to sites of cell-cell contact and functions as an adapter protein, linking the plasma membrane to the cytoskeleton or associated cytoplasmic signaling effectors and facilitating their activities in various pathways. Protein 4.1B/DAL-1 is involved in various cytoskeleton-associated processes, such as cell motility and adhesion. Moreover, protein 4.1B/DAL-1 also plays a regulatory role in cell growth, differentiation, and the establishment of epithelial-like cell structures. Protein 4.1B/DAL-1 is normally expressed in multiple human tissues, but loss of its expression or prominent down-regulation of its expression is frequently observed in corresponding tumor tissues and tumor cell lines, suggesting that protein 4.1B/DAL-1 is involved in the molecular pathogenesis of these tumors and acts as a potential tumor suppressor. This review will focus on the structure of protein 4.1B/DAL-1, 4.1B/DAL-1-interacting molecules, 4.1B/DAL-1 inactivation and tumor progression, and anti-tumor activity of the 4.1B/DAL-1.
Related JoVE Video
Identification and characterization of novel serum microRNA candidates from deep sequencing in cervical cancer patients.
Sci Rep
PUBLISHED: 09-03-2014
Show Abstract
Hide Abstract
Small non-coding microRNAs (miRNAs) are involved in cancer development and progression, and serum profiles of cervical cancer patients may be useful for identifying novel miRNAs. We performed deep sequencing on serum pools of cervical cancer patients and healthy controls with 3 replicates and constructed a small RNA library. We used MIREAP to predict novel miRNAs and identified 2 putative novel miRNAs between serum pools of cervical cancer patients and healthy controls after filtering out pseudo-pre-miRNAs using Triplet-SVM analysis. The 2 putative novel miRNAs were validated by real time PCR and were significantly decreased in cervical cancer patients compared with healthy controls. One novel miRNA had an area under curve (AUC) of 0.921 (95% CI: 0.883, 0.959) with a sensitivity of 85.7% and a specificity of 88.2% when discriminating between cervical cancer patients and healthy controls. Our results suggest that characterizing serum profiles of cervical cancers by Solexa sequencing may be a good method for identifying novel miRNAs and that the validated novel miRNAs described here may be cervical cancer-associated biomarkers.
Related JoVE Video
Multimodal nonlinear optical microscopic imaging provides new insights into acetowhitening mechanisms in live mammalian cells without labeling.
Biomed Opt Express
PUBLISHED: 09-01-2014
Show Abstract
Hide Abstract
We developed a multimodal nonlinear optical microscopy imaging (e.g., third-harmonic generation (THG) and two-photon excited fluorescence (TPEF)) platform based on a femtosecond laser pumped photonic crystal fiber to investigate the acetowhitening phenomenon induced by acetic acid in live mammalian cells without labeling. After treated by acetic acid with concentrations of higher than 0.2%, THG images show that light scattering is remarkably increased inside the nucleus and cytoplasm in cells. Co-localized TPEF and THG imaging on tryptophan and NADH in cells indicates that the change of scattering property is largely originating from the morphological change of metabolic proteins induced by acetic acids. Further TPEF imaging on NADH and FAD in cells confirms that this change is irreversible when acetic acid concentration is higher than 1.2%. These subcellular-level THG/TPEF imaging results reveal that the acetowhitening phenomenon is highly related with proteins involved in metabolic pathways in the nucleus and cytoplasm in live cells.
Related JoVE Video
[Effects of iron on the algae growth and microcystin synthesis: a review].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 08-19-2014
Show Abstract
Hide Abstract
Iron, as one of the essential mineral elements for algae growth, plays an extremely important role in the physiological processes such as plant photosynthesis, respiration, nitrogen fixation, protein and nucleic acid synthesis. In view of the fact that iron in different forms could be absorbed and utilized by algae, the existing forms and circulation approaches in the aquatic environment, the absorption mechanism by algae, and the effects on algae growth and microcystin synthesis were reviewed in this paper. The relevant microcystin synthesis genes and their expression under iron restricted conditions were summarized, and the research directions for harmful algal blooms regulation and control by ferritin genes were suggested. It was hoped to provide the reference for eutrophication remediation technology.
Related JoVE Video
Angiotensin-converting enzyme insertion/deletion polymorphism and gastric cancer: A systematic review and meta-analysis.
Clin Res Hepatol Gastroenterol
PUBLISHED: 08-18-2014
Show Abstract
Hide Abstract
Several studies were launched to investigate the potential function of ACE I/D polymorphism in gastric cancer development and prognosis, but no conclusive results have been obtained. We conducted a systematic review and meta-analysis to evaluate the association between ACE I/D polymorphism and gastric cancer.
Related JoVE Video
Comparison of Chromogenic In Situ Hybridization and Fluorescence In Situ Hybridization for the Evaluation of MDM2 Amplification in Adipocytic Tumors.
J. Clin. Lab. Anal.
PUBLISHED: 08-17-2014
Show Abstract
Hide Abstract
Atypical lipomatous tumor/well-differentiated liposarcoma (ALT-WDLPS) and dedifferentiated liposarcoma (DDLPS) are characterized cytogenetically by a 12q13-15 amplification involving the mouse double minute 2 (MDM2) oncogene. Fluorescence in situ hybridization (FISH) is used frequently to detect this amplification and aid with the diagnosis of these entities, which is difficult by morphology alone. Recently, bright-field in situ hybridization techniques such as chromogenic in situ hybridization (CISH) have been introduced for the determination of MDM2 amplification status.
Related JoVE Video
[94 km Brillouin distributed optical fiber sensors based on ultra-long fiber ring laser pumping].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 08-07-2014
Show Abstract
Hide Abstract
A novel optical amplification configuration based on ultra-long fiber laser with a ring cavity was proposed and applied to Brillouin optical time-domain analysis (BOTDA) sensing system, in order to extend the measurement distance significantly. The parameters used in the experiment were optimized, considering the main limitations of the setup, such as depletion, self-phase modulation (SPM) and pump-signal relative intensity noise (RIN) transfer. Through analyzing Brillouin gain spectrum, we demonstrated distributed sensing over 94 km of standard single-mode fiber with 3 meter spatial resolution and strain/temperature accuracy of 28 /1. 4 degree C.
Related JoVE Video
Calibration of optical tweezers based on an autoregressive model.
Opt Express
PUBLISHED: 08-05-2014
Show Abstract
Hide Abstract
The power spectrum density (PSD) has long been explored for calibrating optical tweezers stiffness. Fast Fourier Transform (FFT) based spectral estimator is typically used. This approach requires a relatively longer data acquisition time to achieve adequate spectral resolution. In this paper, an autoregressive (AR) model is proposed to obtain the Spectrum Density using a limited number of samples. According to our method, the arithmetic model has been established with burg arithmetic, and the final prediction error criterion has been used to select the most appropriate order of the AR model, the power spectrum density has been estimated based the AR model. Then, the optical tweezers stiffness has been determined with the simple calculation from the power spectrum. Since only a small number of samples are used, the data acquisition time is significantly reduced and real-time stiffness calibration becomes feasible. To test this calibration method, we study the variation of the trap stiffness as a function of the parameters of the data length and the trapping depth. Both of the simulation and experiment results have showed that the presented method returns precise results and outperforms the conventional FFT method when using a limited number of samples.
Related JoVE Video
Heme oxygenase-1 gene promoter polymorphism is associated with the development of necrotizing acute pancreatitis.
Pancreas
PUBLISHED: 07-19-2014
Show Abstract
Hide Abstract
Acute pancreatitis is a severe and frequently life-threatening disease, which can lead to pancreatic necrosis, acute lung injury, systemic inflammatory response syndrome, and other complications. In this study, we hypothesized that the expression of heme oxygenase-1 determined by the number of guanidinium thiocyanate (GT) repeats can influence the occurrence of acute pancreatitis.
Related JoVE Video
[Down-regulation of Notch1 by small interfering RNA enhances chemosensitivity to gemcitabine in pancreatic cancer cells through activating apoptosis activity].
Zhejiang Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 07-08-2014
Show Abstract
Hide Abstract
To investigate the effect of down-regulation of Notch1 by Notch1 small interfering RNA ?siRNA? on chemosensitivity to gemcitabine in pancreatic cancer cells and its mechanism.
Related JoVE Video
[DC-derived exosomes induce osteogenic differentiation of mesenchymal stem cells].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 07-04-2014
Show Abstract
Hide Abstract
This study was aimed to investigate the effect of dendritic cell-derived exosome (DCex) on in vitro osteoblast differentiation of human bone marrow mesenchymal stem cells (hBM-MSC). DCex were harvested from the DC culture supernatants by ultracentrifugation. The morphology of DCex was observed by using transmission electron microscopy and the surface marker expression was detected by flow cytometry. MSCs at passage 3 were used in this study. DCex incorporation into MSCs was observed under a confocal microscope. MSCs were either exposed to DCex (10 µg/ml) or the standard osteogeneic induction condition. The cells cultured in complete medium were served as the control. The expression levels of Runt related transcription factor 2 (Runx2) were detected by real-time and standard PCR. The cellular alkaline phosphatase (ALP) activity was also detected. The results showed that the DCex were spherical or oval membrane vesicles with diameters of about 40-100 nm under transmission electron microscope. The DCex expressed surface molecules specific for DCs, including CD83, CD86, CD80, and HLA-DR. After cultured for 7 days, the MSCs treated with DCex highly expressed Runx2 as compared with the control group (P < 0.05). After cultured for 14 days, ALP activity of the DCex-treated MSCs was markedly higher than the control group (P < 0.01), though it was lower than that of MSCs treated with standard inductive agents. It is concluded that DCex can induce MSCs to differentiate into osteoblasts. The detailed investigations are needed to clarify the underlying mechanisms.
Related JoVE Video
Microwave assisted tandem Heck-Sonogashira reactions of N,N-di-Boc-protected 6-amino-5-iodo-2-methyl pyrimidin-4-ol in an efficient approach to functionalized pyrido[2,3-d]pyrimidines.
Org. Lett.
PUBLISHED: 06-23-2014
Show Abstract
Hide Abstract
A microwave assisted tandem Heck-Sonogashira cross-coupling reaction between 6-N,N-di-Boc-amino-5-iodo-2-methyl pyrimidin-4-ol and various aryl alkynyl substrates has been developed. This process generates novel 5-enynyl substituted pyrimidines, which can be transformed to novel functionalized pyrido[2,3-d]pyrimidines by way of a silver catalyzed cyclization reaction.
Related JoVE Video
[Effect of Zhifei mixture combined western drugs on symptoms and signs of children with mycoplasma pneumonia].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 06-20-2014
Show Abstract
Hide Abstract
To observe the effect of three Chinese medical formulae (Zhifei Mixture I , Zhfei Mixture II, and Zhifei Mixture II) on main and secondary symptoms and signs of children with Totally 70 mycoplasma pneumonia in treating three types of children mycoplasma pneumonia.
Related JoVE Video
Ultra-long high-sensitivity ?-OTDR for high spatial resolution intrusion detection of pipelines.
Opt Express
PUBLISHED: 06-13-2014
Show Abstract
Hide Abstract
An ultra-long phase-sensitive optical time domain reflectometry (?-OTDR) that can achieve high-sensitivity intrusion detection over 131.5km fiber with high spatial resolution of 8m is presented, which is the longest ?-OTDR reported to date, to the best of our knowledge. It is found that the combination of distributed Raman amplification with heterodyne detection can extend the sensing distance and enhances the sensitivity substantially, leading to the realization of ultra-long ?-OTDR with high sensitivity and spatial resolution. Furthermore, the feasibility of applying such an ultra-long ?-OTDR to pipeline security monitoring is demonstrated and the features of intrusion signal can be extracted with improved SNR by using the wavelet detrending/denoising method proposed.
Related JoVE Video
Network-guided regression for detecting associations between DNA methylation and gene expression.
Bioinformatics
PUBLISHED: 06-11-2014
Show Abstract
Hide Abstract
High-throughput profiling in biological research has resulted in the availability of a wealth of data cataloguing the genetic, epigenetic and transcriptional states of cells. These data could yield discoveries that may lead to breakthroughs in the diagnosis and treatment of human disease, but require statistical methods designed to find the most relevant patterns from millions of potential interactions. Aberrant DNA methylation is often a feature of cancer, and has been proposed as a therapeutic target. However, the relationship between DNA methylation and gene expression remains poorly understood.
Related JoVE Video
Effects of let-7b and TLX on the proliferation and differentiation of retinal progenitor cells in vitro.
Sci Rep
PUBLISHED: 06-06-2014
Show Abstract
Hide Abstract
MicroRNAs manifest significant functions in brain neural stem cell (NSC) self-renewal and differentiation through the post-transcriptional regulation of neurogenesis genes. Let-7b is expressed in the mammalian brain and regulates NSC proliferation and differentiation by targeting the nuclear receptor TLX, which is an essential regulator of NSC self-renewal. Whether let-7b and TLX act as important regulators in retinal progenitor cell (RPC) proliferation and differentiation remains unknown. Here, our data show that let-7b and TLX play important roles in controlling RPC fate determination in vitro. Let-7b suppresses TLX expression to negatively regulate RPC proliferation and accelerate the neuronal and glial differentiation of RPCs. The overexpression of let-7b downregulates TLX levels in RPCs, leading to reduced RPC proliferation and increased neuronal and glial differentiation, whereas antisense knockdown of let-7b produces robust TLX expression,enhanced RPC proliferation and decreased differentiation. Moreover, the inhibition of endogenous TLX by small interfering RNA suppresses RPC proliferation and promotes RPC differentiation. Furthermore, overexpression of TLX rescues let-7b-induced proliferation deficiency and weakens the RPC differentiation enhancement caused by let-7b alone. These results suggest that let-7b, by forming a negative feedback loop with TLX, provides a novel model to regulate the proliferation and differentiation of retinal progenitors in vitro.
Related JoVE Video
Dosimetric comparison of intensity modulated and volumetric arc radiation therapy for gastric cancer.
Oncol Lett
PUBLISHED: 05-07-2014
Show Abstract
Hide Abstract
The aim of the present study was to compare radiotherapy treatment plans for gastric cancer using intensity-modulated radiotherapy (IMRT) and single/double-arc volumetric modulated arc therapy (SA/DA-VMAT) delivery techniques. A total of 29 postoperative gastric cancer patients were enrolled in this study and each patient was scheduled 5-field IMRT (5F-IMRT), 7-field IMRT (7F-IMRT), SA-VMAT and DA-VMAT techniques. Dose-volume histogram statistics, conformal index (CI), homogeneity index (HI) and monitor units (MUs) were analyzed to compare treatment plans. The DA-VMAT plans exceeded the other three methods in terms of planning tumor volume dose and organs at risk in the kidneys, but not in the liver. DA-VMAT exhibited a better mean CI (0.87±0.03) and HI (0.10±0.01) than the other techniques. In addition, for the kidneys the dose sparing (V13, V18 and mean kidney dose) was improved by DA-VMAT plans. Similar results were observed for MUs. However, 5F-IMRT showed a marginal advantage in V30 and mean dose in normal liver when compared with DA-VMAT. The results of this study suggest that DA-VMAT provides improved tumor coverage when compared with 5F-IMRT, 7F-IMRT and SA-VMAT; however, DA-VMAT exhibits no advantage in liver protection when compared with 5F-IMRT. Further studies are required to establish differences in treatment outcomes among the four technologies.
Related JoVE Video
Axonal Transport Defects in Alzheimer's Disease.
Mol. Neurobiol.
PUBLISHED: 05-04-2014
Show Abstract
Hide Abstract
A large body of evidences indicates that axonal transport (AT) defects play an important role in the pathogenesis of Alzheimer' disease (AD). AT, a critical cellular process for the maintenance and function of a neuron, requires components of the cytoskeletons as "tracks", motor proteins and ATP as "driving force", adaptor proteins to ensure the specific connection of the transported cargoes and motor proteins as well as active regulation. In AD pathology, AD-linked pathologic factors respectively perturb the four basic components of AT through different signaling pathways to cause AT defects. Mitochondrial transport, which is different from other transport cargoes, is also impaired via special pathways in AD. In this paper, we review the inhibitory effects of those factors on AT and their possible pathways, indicating these factors act in overlapping, synergistic, and circulating ways. Given the contributions of AT defects to AD, recent therapeutic studies focus on microtubule-stabilizing (MT-stabilizing) agents and alteration in phosphotransferase activities, and we propose more therapeutic strategies targeting AT defects.
Related JoVE Video
Rapid screening and identification of target constituents using full scan-parent ions list-dynamic exclusion acquisition coupled to diagnostic product ions analysis on a hybrid LTQ-Orbitrap mass spectrometer.
Talanta
PUBLISHED: 04-29-2014
Show Abstract
Hide Abstract
A highly sensitive and effective strategy for rapid screening and identification of target constituents has been developed using full scan-parent ions list-dynamic exclusion (FS-PIL-DE) acquisition coupled to diagnostic product ions (DPIs) analysis on a hybrid LTQ-Orbitrap mass spectrometer. The FS-PIL-DE was adopted as a survey scan to trigger the MS/MS acquisition of all the predictable constituents contained in traditional Chinese medicines. Additionally, DPIs analysis can provide a criterion to judge the target constituents detected into certain chemical families. Results from analyzing polymethoxylated flavonoids (PMFs) in the leaves of Citrus reticulata Blanco demonstrated that FS-PIL-DE was capable of targeting a greater number of constituents than FS, FS-PIL and FS-DE, thereby increasing the coverage of constituent screening. As a result, 135 PMFs including 81 polymethoxyflavones, 54 polymethoxyflavanones or polymethoxychalcones were identified preliminarily. And this was the first time to systematically report the presence of PMFs in the leaves of Citrus reticulata Blanco, especially for polymethoxylated flavanones and chalcones, most of which were new compounds. The results indicated that the developed FS-PIL-DE coupled to DPIs analysis methodology could be employed as a rapid, effective technique to screen and identify target constituents from TCMs extracts and other organic matter mixtures whose compounds contained can also be classified into families based on the common carbon skeletons.
Related JoVE Video
Intestinal microbiota pathogenesis and fecal microbiota transplantation for inflammatory bowel disease.
World J. Gastroenterol.
PUBLISHED: 04-26-2014
Show Abstract
Hide Abstract
The intestinal microbiota plays an important role in inflammatory bowel disease (IBD). The pathogenesis of IBD involves inappropriate ongoing activation of the mucosal immune system driven by abnormal intestinal microbiota in genetically predisposed individuals. However, there are still no definitive microbial pathogens linked to the onset of IBD. The composition and function of the intestinal microbiota and their metabolites are indeed disturbed in IBD patients. The special alterations of gut microbiota associated with IBD remain to be evaluated. The microbial interactions and host-microbe immune interactions are still not clarified. Limitations of present probiotic products in IBD are mainly due to modest clinical efficacy, few available strains and no standardized administration. Fecal microbiota transplantation (FMT) may restore intestinal microbial homeostasis, and preliminary data have shown the clinical efficacy of FMT on refractory IBD or IBD combined with Clostridium difficile infection. Additionally, synthetic microbiota transplantation with the defined composition of fecal microbiota is also a promising therapeutic approach for IBD. However, FMT-related barriers, including the mechanism of restoring gut microbiota, standardized donor screening, fecal material preparation and administration, and long-term safety should be resolved. The role of intestinal microbiota and FMT in IBD should be further investigated by metagenomic and metatranscriptomic analyses combined with germ-free/human flora-associated animals and chemostat gut models.
Related JoVE Video
[Promoting effect of thrombin on proliferation of bone marrow-derived mesenchymal stem cells and its mechanisms].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 04-26-2014
Show Abstract
Hide Abstract
This study was aimed to investigate the growth-promoting activity of thrombin on mesenchymal stem cells (MSC) and its mechanisms. Human bone marrow MSC were cultured in serum-free medium supplemented with graded concentrations of thrombin, and the proliferation status of MSC was detected by MTT test. The expression levels of protease-activated receptors (PAR) and c-MYC gene were detected by PCR. Activated Akt signaling pathway was revealed by Western blot, and specific inhibitors of the signaling pathways were used to confirm the effects. The results showed that thrombin stimulated MSC proliferation in a dose-dependent manner; the minimal concentration of thrombin for stimulating MSC growth was 0.5 U/ml, and the promoting effect reached its maximum when thrombin at a dose of 8 U/ml was employed. PCR results showed that MSC expressed the two types of PAR1 and PAR2. After PAR1 was blocked with a specific inhibitor SCH79797, the growth-promoting effect of thrombin was inhibited, while this phenomenon was not observed when MSC were exposed to FSLLRY-NH2, a specific inhibitor for PAR2. Further experiments showed that after exposure to thrombin, the AKT signaling pathway in MSC was promptly activated, and c-MYC expression was greatly up-regulated. Meanwhile, when LY294002, a specific AKT inhibitor, was added into the culture medium, the up-regulation of c-MYC expression was reduced, accompanied by the low rate of MSC growth. It is concluded that thrombin can stimulate MSC proliferation by eliciting PAR1-mediated AKT activation and subsequent up-regulation of c-MYC expression.
Related JoVE Video
?-N-methylation of damaged DNA-binding protein 2 (DDB2) and its function in nucleotide excision repair.
J. Biol. Chem.
PUBLISHED: 04-21-2014
Show Abstract
Hide Abstract
DDB2 exhibits a high affinity toward UV-damaged DNA, and it is involved in the initial steps of global genome nucleotide excision repair. Mutations in the DDB2 gene cause the genetic complementation group E of xeroderma pigmentosum, an autosomal recessive disease manifested clinically by hypersensitivity to sunlight exposure and an increased predisposition to skin cancer. Here we found that, in human cells, the initiating methionine residue in DDB2 was removed and that the N-terminal alanine could be methylated on its ?-amino group in human cells, with trimethylation being the major form. We also demonstrated that the ?-N-methylation of DDB2 is catalyzed by the N-terminal RCC1 methyltransferase. In addition, a methylation-defective mutant of DDB2 displayed diminished nuclear localization and was recruited at a reduced efficiency to UV-induced cyclobutane pyrimidine dimer foci. Moreover, loss of this methylation conferred compromised ATM (ataxia telangiectasia mutated) activation, decreased efficiency in cyclobutane pyrimidine dimer repair, and elevated sensitivity of cells toward UV light exposure. Our study provides new knowledge about the posttranslational regulation of DDB2 and expands the biological functions of protein ?-N-methylation to DNA repair.
Related JoVE Video
Alternate heteroepitaxial growth of highly oriented organic multilayer films.
J Phys Chem B
PUBLISHED: 04-09-2014
Show Abstract
Hide Abstract
The heterostructure, a basic active unit applied in the device level, plays an important role in traditional inorganic optoelectronics. In the organic field, although the requirement for the heterostructure is crucial, achievement and understanding on the growth and functionality of organic heterostructure are still finite, especially for ordered crystalline organic multilayers with smooth interfaces. Here a series of highly ordered crystalline heterostructures with molecule-level smoothness were obtained from single layer to alternate multilayer with a phthalocyanine molecule and a perylene derivative. Well-defined epitaxy relationship and crystal alignment were evidenced from the atomic force microscopy (AFM), X-ray diffraction (XRD), and transmission electron microscope (TEM) results. The evolution of the films reveals that, for organic-organic alternate multilayer growth, along with the intrinsic properties of organic molecules such as the packing and preferred growth direction, the soft matter properties of organic films contribute to well-defined heteroepitaxy despite that the lattice mismatch between the two materials' bulk phases is large. Thin film phases of the first few layers benefit the grain coalescence and thus the formation of smooth films. Potential application is implied from the heterojunctions' good transport ability.
Related JoVE Video
Association between co-stimulatory molecule gene polymorphism and acute rejection of allograft.
Transpl. Immunol.
PUBLISHED: 03-31-2014
Show Abstract
Hide Abstract
Co-stimulatory molecules play important roles in T cell-mediated immune response and transplantation. Numerous epidemiological studies have evaluated the association between CD28, CTLA-4 gene variant and allograft rejection. However, the results of these studies on the association remain conflicting. The main purpose of this study was to integrate previous results and explore whether the CD28 IVS3 +17T/C variant, CTLA-4, CD86 and PDCD1 gene polymorphisms were associated with allograft rejection susceptibility. PubMed and Embase (before 2014-3-25), were searched for studies on the relationship of CD28, CTLA-4, CD86 and PDCD1 gene polymorphisms and the incidence of allograft rejection susceptibility. Eligible articles were included for data extraction. The main outcome was the frequency of co-stimulate molecule gene polymorphisms between rejection and non-rejection populations. Comparison of the distribution of SNP was mainly performed using Review Manager 5.0. The odds ratio (OR) and its 95% confidence interval (95% CI) were used to assess the strength of association. Significant associations of the CD28 IVS3 +17T/C variant with acute allograft rejection susceptibility were found (CC +CT/TT OR, 1.45; 95% CI, 1.08-1.94; P=0.01). Also we found an association of the CD28 IVS3 +17T/C variant with kidney allograft rejection cases (CC +CT/TT OR, 1.72; 95% CI, 1.19-2.49; P=0.004) and (C allele OR, 1.74; 95% CI, 1.11-2.75; P=0.02), but not established for liver allograft rejection cases (CC +CT/TT OR, 1.19; 95% CI, 0.47-2.98; P=0.72) and (C allele OR, 0.96; 95% CI, 0.67-1.39; P=0.84). And we found an association of the CD86 +1057G/A variant with non-allograft rejection cases (AA +AG/GG OR, 0.35; 95% CI, 0.14-0.85; P=0.02). This meta-analysis demonstrates that the CD28 IVS3 +17T/C variant might increase acute allograft rejection risk in kidney transplant but not in liver transplant, and there was an association between CD86 +1057G/A variant and reduced acute rejection risk. Further studies will be needed to confirm our findings.
Related JoVE Video
Clinical value of serum tumor markers CA19-9, CA125 and CA72-4 in the diagnosis of pancreatic carcinoma.
Mol Clin Oncol
PUBLISHED: 03-21-2014
Show Abstract
Hide Abstract
CA125 and CA72-4 are members of a family of high-molecular weight glycosylated proteins and are commonly considered as biomarkers in the diagnosis of ovarian and gastric cancer, respectively. However, recent studies have revealed that these two markers may be of clinical value in the diagnosis of pancreatic cancer. As the availability of data regarding CA72-4 and CA125 in the diagnosis of pancreatic cancer is limited, the aim of this study was to investigate the clinical value of serum tumor markers CA19-9, CA125 and CA72-4 in the diagnosis of pancreatic carcinoma according to logistic regression analysis and receiver operating characteristic (ROC) curves and to investigate the correlation of these markers with tumor TNM stage and location. An immunoradiometric assay was used to measure pre-operative serum CA19-9, CA125 and CA72-4 levels in 75 patients with pancreatic carcinoma and 70 patients with benign pancreatic diseases. The concentrations of serum CA19-9, CA125 and CA72-4 in patients with pancreatic carcinoma were found to be significantly higher (P<0.05) compared with those with benign pancreatic diseases. The combined detection of two serum markers (CA19-9 + CA72-4) yielded a ROC value of 0.895 that was significantly higher compared to others (P<0.05) in distinguishing pancreatic cancer from benign pancreatic diseases. At optimal cut-off, the sensitivity and specificity of combined detection (CA19-9 + CA72-4) were 70.6 and 92.8%, respectively. The concentrations of CA125 and CA19-9 in patients with pancreatic adenocarcinoma were found to be significantly higher (P<0.05) compared with those of pancreatic neuroendocrine carcinoma. In conclusion, the combined detection of CA19-9 and CA72-4) may significantly improve the diagnostic specificity and the serum concentrations of CA125 and CA19-9 are correlated with tumor histological type.
Related JoVE Video
The correlation of magnetoencephalography to intracranial EEG in localizing the epileptogenic zone: A study of the surgical resection outcome.
Epilepsy Res.
PUBLISHED: 03-17-2014
Show Abstract
Hide Abstract
To evaluate the agreement between magnetoencephalography (MEG) and intracranial electroencephalography (ICEEG) results, to determine the characteristics that lead to concordance, and to assess how these factors relate to favorable epilepsy surgery outcome.
Related JoVE Video
IKK? restoration via EZH2 suppression induces nasopharyngeal carcinoma differentiation.
Nat Commun
PUBLISHED: 03-14-2014
Show Abstract
Hide Abstract
Lack of cellular differentiation is a key feature of nasopharyngeal carcinoma (NPC), but it also presents as a unique opportunity for intervention by differentiation therapy. Here using RNA-seq profiling analysis and functional assays, we demonstrate that reduced IKK? expression is responsible for the undifferentiated phenotype of NPC. Conversely, overexpression of IKK? induces differentiation and reduces tumorigenicity of NPC cells without activating NF-?B signalling. Importantly, we describe a mechanism whereby EZH2 directs IKK? transcriptional repression via H3K27 histone methylation on the IKK? promoter. The differentiation agent, retinoic acid, increases IKK? expression by suppressing EZH2-mediated H3K27 histone methylation, resulting in enhanced differentiation of NPC cells. In agreement, an inverse correlation between IKK? (low) and EZH2 (high) expression is associated with a lack of differentiation in NPC patient samples. Collectively, these findings demonstrate a role for IKK? in NPC differentiation and reveal an epigenetic mechanism for IKK? regulation, unveiling a new avenue for differentiation therapy.
Related JoVE Video
Thrombin promotes fibronectin secretion by bone marrow mesenchymal stem cells via the protease-activated receptor mediated signalling pathways.
Stem Cell Res Ther
PUBLISHED: 03-12-2014
Show Abstract
Hide Abstract
Fibronectin (FN) is commonly used in the development of serum-free media for the expansion of mesenchymal stem cells (MSCs). This study was aimed to observe if thrombin could stimulate FN secretion by human bone marrow MSCs and investigate the potential underlying mechanisms.
Related JoVE Video
Natural course and predictors of spontaneous seizure remission in idiopathic generalized epilepsy: 7-27 years of follow-up.
Epilepsy Res.
PUBLISHED: 03-05-2014
Show Abstract
Hide Abstract
The spontaneous course of idiopathic generalized epilepsy (IGE) is still controversial. The aim of this study was both to investigate the long-term spontaneous course and to identify factors that are predictive for epilepsy remission in a small cohort of 15 IGE patients (9 women) who refused antiepileptic drug (AED) treatment and therefore never have been treated with AED. All of them were reevaluated with a review of their medical records and direct face-to-face interview; the mean duration of follow-up was 15.3 years. Five (33.3%) of them had absence epilepsy (absence seizures, ABS), 5 had IGE with generalized tonic-clonic seizures (GTCS), and another 5 had both seizure types (IGE with ABS/GTCS). Rate of epilepsy remission was 53.3% with a mean time of seizure freedom of 13.1 years; rate of remission was highest among absence epilepsy patients (80%), followed by IGE with GTCS (60%) and IGE with ABS/GTCS (20%). The frequency of spontaneous generalized interictal epileptiform discharges in electroencephalography is not associated with the long-term seizure outcome (p=0.201) and per se does not require AED treatment. Furthermore, the occurrence of photoparoxysmal responses (p=0.020) as well as the occurrence of more than 3 GTCS during the course (p=0.029) were identified as significant predictors for a poor long-term seizure outcome which makes AED treatment indispensable in these patients. This study underlines the heterogenity of the group of IGE. AED treatment has no impact on the spontaneous course of IGE with ABS and/or GTCS. Several predictors for the long-term seizure outcome in patients with IGE were identified in this study.
Related JoVE Video
Depiction of transplant renal vascular anatomy and complications: unenhanced MR angiography by using spatial labeling with multiple inversion pulses.
Radiology
PUBLISHED: 03-03-2014
Show Abstract
Hide Abstract
To evaluate the ability to depict anatomy and complications of renal vascular transplant with unenhanced magnetic resonance (MR) angiography with spatial labeling with multiple inversion pulses (SLEEK) and to compare the results with color Doppler (CD) ultrasonography (US), digital subtraction angiography (DSA), and intraoperative findings.
Related JoVE Video
MiRNA-125a-5p: a regulator and predictor of gefitinib's effect on nasopharyngeal carcinoma.
Cancer Cell Int.
PUBLISHED: 03-01-2014
Show Abstract
Hide Abstract
Nasopharyngeal carcinoma (NPC) is a common malignancy in China and Southeast Asia. Radiotherapy is the major treatment modality for patients with NPC, but does not always achieve fully satisfactory outcomes. Studies have shown that epidermal growth factor receptor (EGFR) is highly expressed in NPC, and EGFR-targeted treatment is expected to be a new strategy for NPC. Recently, clinical trials have shown that NPC patients have different responses to gefitinib. Thus, the identification of indicators that can regulate and predict the sensitivity of NPC to gefitinib is very valuable. MiRNAs (MicroRNAs) are closely related to cancer development. We studied miRNAs in NPC cell lines to identify those that can regulate and predict the effectiveness of gefitinib on NPC.
Related JoVE Video
Aberrant expression of the autocrine motility factor receptor correlates with poor prognosis and promotes metastasis in gastric carcinoma.
Asian Pac. J. Cancer Prev.
PUBLISHED: 02-27-2014
Show Abstract
Hide Abstract
AMFR, autocrine motility factor receptor, also called gp78, is a cell surface cytokine receptor which has a dual role as an E3 ubiquitin ligase in endoplasmic reticulum-associated degradation. AMFR expression is associated with tumor malignancy. We here investigated the clinical significance of AMFR and its role in metastasis and prognosis in gastric cancer. Expression of AMFR, E-cadherin and N-cadherin in cancer tissues and matched adjacent normal tissues from 122 gastric cancer (GC) patients undergoing surgical resection was assessed by immunohistochemistry. Levels of these molecules in 17 cases selected randomly were also analysed by Western blotting. AMFR expression was significantly increased in gastric cancer tissues, and associated with invasion depth and lymph node metastasis. Kaplan-Meier analysis showed AMFR expression correlated with poor overall survival and an increased risk of recurrence in the GC cases. Cox regression analysis suggested AMFR to be an independent predictor for overall and recurrence-free survival. E-cadherin expression was decreased in gastric cancer tissues; conversely, N-cadherin was increased. Expression of AMFR negatively correlated with E-cadherin expression, whereas N-cadherin expression showed a significant positive correlation with AMFR expression. AMFR might be involved in the regulation of epithelial-mesenchymal transition, with aberrant expression correlating with a poor prognosis and promoting invasion and metastasis in GCs.
Related JoVE Video
Design and synthesis of copper-cobalt catalysts for the selective conversion of synthesis gas to ethanol and higher alcohols.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 02-21-2014
Show Abstract
Hide Abstract
Combining quantum-mechanical simulations and synthesis tools allows the design of highly efficient CuCo/MoO(x) catalysts for the selective conversion of synthesis gas (CO+H2) into ethanol and higher alcohols, which are of eminent interest for the production of platform chemicals from non-petroleum feedstocks. Density functional theory calculations coupled to microkinetic models identify mixed Cu-Co alloy sites, at Co-enriched surfaces, as ideal for the selective production of long-chain alcohols. Accordingly, a versatile synthesis route is developed based on metal nanoparticle exsolution from a molybdate precursor compound whose crystalline structure isomorphically accommodates Cu(2+) and Co(2+) cations in a wide range of compositions. As revealed by energy-dispersive X-ray nanospectroscopy and temperature-resolved X-ray diffraction, superior mixing of Cu and Co species promotes formation of CuCo alloy nanocrystals after activation, leading to two orders of magnitude higher yield to high alcohols than a benchmark CuCoCr catalyst. Substantiating simulations, the yield to high alcohols is maximized in parallel to the CuCo alloy contribution, for Co-rich surface compositions, for which Cu phase segregation is prevented.
Related JoVE Video
Transthoracic vs transhiatal surgery for cancer of the esophagogastric junction: a meta-analysis.
World J. Gastroenterol.
PUBLISHED: 02-13-2014
Show Abstract
Hide Abstract
To compare the efficacy and safety of the transthoracic and transhiatal approaches for cancer of the esophagogastric junction.
Related JoVE Video
An organic quantum well based on high-quality crystalline heteroepitaxy films.
Adv. Mater. Weinheim
PUBLISHED: 02-13-2014
Show Abstract
Hide Abstract
A meaningful organic quantum well based on crystalline heteroepitaxy films is constructed. The quantum confinement effect is demonstrated by its reflections on optics and electrics: the blueshift of the optical characteristic peaks and the negative differential resistance at room temperature. The realization of an organic quantum well indicates the highly delocalized transport mechanism in well-defined organic crystalline systems and promises novel organic "quantum" optoelectronic devices.
Related JoVE Video
Effects of miR-31 on the osteogenesis of human mesenchymal stem cells.
Biochem. Biophys. Res. Commun.
PUBLISHED: 02-09-2014
Show Abstract
Hide Abstract
Exploring the molecular mechanisms that regulate the osteogenesis of human mesenchymal stem cells (hMSCs) will bring us more efficient methods for improving the treatment of bone-related diseases. In this study, we analyzed the effects of miR-31 on the osteogenesis of hMSCs. The overexpression of miR-31 repressed the osteogenesis of hMSCs, whereas the downregulation enhanced this process. SATB2 was testified to be a direct target of miR-31, and its effects on the osteogenesis were also described. Most importantly, the knockdown of SATB2 attenuated miR-31's osteogenic effects. Taken together, our findings suggest that miR-31 regulates the osteogenesis of hMSCs by targeting SATB2.
Related JoVE Video
Rapid and sensitive detection of human astrovirus in water samples by loop-mediated isothermal amplification with hydroxynaphthol blue dye.
BMC Microbiol.
PUBLISHED: 02-06-2014
Show Abstract
Hide Abstract
The aim of this paper was to develop a reverse transcription loop-mediated isothermal amplification (RT-LAMP) method for rapid, sensitive and inexpensive detection of astrovirus.
Related JoVE Video
Clostridium difficile colonization and disease in patients undergoing hematopoietic stem cell transplantation.
Biol. Blood Marrow Transplant.
PUBLISHED: 02-05-2014
Show Abstract
Hide Abstract
There was an increase in the Clostridium difficile infection (CDI) rate in our bone marrow transplantation unit. To evaluate the role of unit-based transmission, C. difficile screening was performed on adult patients admitted for hematopoietic stem cell transplantation (HSCT) over a 2-year period, and C. difficile isolates were typed. C. difficile testing was performed using a 2-step C. difficile glutamate dehydrogenase antigen plus toxin A/B enzyme immunoassay (EIA) and cytotoxin assay (or molecular toxin assay). Multilocus sequence typing (MLST) was performed on toxin-positive whole stool samples. A retrospective chart review was performed on all patients with a positive toxin assay. Sixteen of 150 patients (10.7%) had toxigenic C. difficile colonization (CDC) on admission. The overall incidence of CDI within 100 days after HSCT was 24.7% (37 of 150). The median time to diagnosis of CDI was 3.5 days after HSCT. In an adjusted logistic regression model, CDC on admission was a significant risk factor for CDI (odds ratio, 68.5; 95% confidence interval, 11.4 to 416.2). MLST on 22 unit patient toxin-positive stool specimens revealed 15 distinct strain types. Further analysis identified at least 1 potential cross-transmission event; some events may have been missed because of incomplete typing from other specimens. Despite aggressive infection control interventions, there was no decline in the number of CDI cases during the study period. These data suggest that prior CDC plays a major role in CDI rates in this high-risk patient population. It remains unclear if CDI was cross-transmitted in the unit.
Related JoVE Video
Investigation on the synthesis of 25-hydroxycholesterol.
Steroids
PUBLISHED: 01-22-2014
Show Abstract
Hide Abstract
A very efficient and environmentally benign method has been developed for the synthesis of 25-hydroxycholesterol. The reaction was performed in THF-water (4:1, v/v) using NBS as the brominating agent, followed by the easy reduction of C-Br with lithium aluminum hydride in THF, to yield the final product corresponding to a Markovnikov's rule. Excellent yields and regioselectivity have been obtained.
Related JoVE Video
Diorganotin(IV) derivatives of substituted N-hydroxybenzamides with selective cytotoxicity in vitro and potent antitumor activity in vivo.
J. Inorg. Biochem.
PUBLISHED: 01-14-2014
Show Abstract
Hide Abstract
Four diorganotin(IV) derivatives, dibutylbis[4-chloro-N-(hydroxy-O)benzamidato-O]tin(IV) (DBDCT), dibutylbis[2,6-difluoro-N-(hydroxy-O)benzamidato-O]tin(IV) (DBDFT), bis[2,4-difluoro-N-(hydroxy-O)benzamidato-O]diphenyltin(IV) (DPDFT), and bis[2,4-dichloro-N-(hydroxy-O)benzamidato-O]diphenyltin(IV) (DPDCT), were compared for their antitumor activity in vitro and in vivo along with their cytotoxic selectivity against human normal cells and cancer cells. The in vitro cytotoxic activities against seven human cancer cell lines including Hep G2, SHSY5Y, HEC-1-B, EC, T24, HeLa and A549 along with human liver HL-7702, a human normal hepatocytes cell, were observed by the MTT assay. The cytotoxic selectivity of the four compounds was compared by using HL-7702 and Hep G2. The in vivo antitumor tests towards the sarcoma carcinoma S180 and hepatocellular carcinoma H22 on mice were carried out via injection intraperitoneally with cisplatin as the positive contrast drug. The results showed that, among the four compounds, DBDCT displayed the strongest cytotoxicity against the seven cancer cell lines. DPDCT had the highest antitumor activity in vivo. However, both of them had no cytotoxic selectivity against the human hepatocellular carcinoma HepG2 cells and normal liver HL-7702 cells. DPDFT had the most significant cytotoxic selectivity against HepG2 and displayed significantly antitumor activity in vitro and in vivo. In conclusion, DPDFT could act as a promising lead compound for the further structure optimization owing to its relatively low toxicity to human normal cell and potent antitumor activity against cancer cells.
Related JoVE Video
Bone marrow mesenchymal stem cell-derived microvesicles protect rat pheochromocytoma PC12 cells from glutamate-induced injury via a PI3K/Akt dependent pathway.
Neurochem. Res.
PUBLISHED: 01-12-2014
Show Abstract
Hide Abstract
Studies have suggested that mesenchymal stem cells (MSCs) can protect neuronal cells from excitotoxicity, but the underlying mechanisms are still remaining elusive. In the study, we show that microvesicles released by rat bone marrow-derived MSCs (rBMSC-MVs) protect rat pheochromocytoma PC12 cells from glutamate-induced excitotoxicity. BMSC-MVs upregulate Akt phosphorylation and Bcl-2 expression, downregulate Bax expression, and reduce the cleavage of caspase-3 in glutamate-treated PC12 cells. Such protective effects are partially abrogated by inhibiting PI3K, indicating that rBMSC-MVs act via the PI3K/Akt pathway. Transplantation of rBMSC-MVs may, therefore, be a promising strategy to treat cerebral injury or some other neuronal diseases involving excitotoxicity.
Related JoVE Video
Hepatocyte growth factor modification enhances the anti-arrhythmic properties of human bone marrow-derived mesenchymal stem cells.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Chronic myocardial infarction (MI) results in the formation of arrhythmogenic substrates, causing lethal ventricular arrhythmia (VA). We aimed to determine whether mesenchymal stem cells (MSCs) carrying a hepatocyte growth factor (HGF) gene modification (HGF-MSCs) decrease the levels of arrhythmogenic substrates and reduce the susceptibility to developing VA compared with unmodified MSCs and PBS in a swine infarction model.
Related JoVE Video
Malignant perivascular epithelioid cell tumor (PEComa) of cervix with TFE3 gene rearrangement: a case report.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
In this study, we reported the first PEComa arising within the cervix with TFE3 gene rearrangement and aggressive biological behavior. Morphologically, the tumor showed infiltrative growth into the surrounding parenchyma. The majority of tumor cells were arrayed in sheets, alveolar structures, or nests separated by delicate fibrovascular septa. There was marked intratumoral hemorrhage, necrosis, and stromal calcifications. The tumor cells had abundant clear cytoplasm, focally containing finely granular dark brown pigment, morphologically considered to be melanin. Immunohistochemically, the tumor cells demonstrated moderately (2+) or strongly (3+) positive staining for TFE3, HMB45, and Melan A but negative for CKpan, SMA, S100, PAX8, and PAX2. The presence of Ki-67 protein demonstrated a moderate proliferation rate, with a few Ki-67-positive nuclei. Using a recently developed TFE3 split FISH assay, the presence of TFE3 rearrangement was demonstrated. All these clinicopathologic features are suggestive of TFE3-rearranged PEComas of the cervix. Our results both expand the known characteristics of primary cervix PEComas and add to the data regarding TFE3 rearrangement-associated PEComas.
Related JoVE Video
Increased expression of IL-37 in patients with Graves' disease and its contribution to suppression of proinflammatory cytokines production in peripheral blood mononuclear cells.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Interleukin-37 (IL-37), a member of IL-1 family, is primarily an anti-inflammatory cytokine, which reduces systemic and local inflammation. However, the expression and role of IL-37 in Graves' disease (GD) remains unknown. This study aims to measure the levels of serum and peripheral blood mononuclear cells (PBMCs) IL-37 in patients with Graves' disease and to examine its association with disease activity. Furthermore, we investigate the effect of IL-37 on proinflammatory cytokines involved in the pathogenesis of GD.
Related JoVE Video
Optical trapping of red blood cells in living animals with a water immersion objective.
Opt Lett
PUBLISHED: 11-28-2013
Show Abstract
Hide Abstract
We demonstrate optical trapping of red blood cells (RBCs) in living animals by using a water immersion objective. First, the cells within biological tissue are mimicked by the particles immersed in aqueous solutions of glycerol. The optical forces depending on trapping depth are investigated when a parallel laser beam enters the water immersion objective. The results show that the optical forces vary with trapping depth, and the optimal trapping depth in aqueous solutions of glycerol (n=1.39) is 50 ?m. Second, the optimal trapping depth in aqueous solutions of glycerol can be changed by altering the actual tube length of the water immersion objective. Finally, we achieved optical trapping and manipulation of RBCs in living mice.
Related JoVE Video
Hybrid distributed Raman amplification combining random fiber laser based 2nd-order and low-noise LD based 1st-order pumping.
Opt Express
PUBLISHED: 10-24-2013
Show Abstract
Hide Abstract
A configuration of hybrid distributed Raman amplification (H-DRA), that is formed by incorporating a random fiber laser (RFL) based 2nd-order pump and a low-noise laser-diode (LD) based 1st-order pump, is proposed in this paper. In comparison to conventional bi-directional 1st-order DRA, the effective noise figure (ENF) is found to be lower by amount of 0 to 4 dB due to the RFL-based 2nd-order pump, depending on the on-off gain, while the low-noise 1st-order Raman pump is used for compensating the worsened signal-to-noise ratio (SNR) in the vicinity towards the far end of the fiber and avoiding the potential nonlinear impact induced by excess injection of pump power and suppressing the pump-signal relative intensity noise (RIN) transfer. As a result, the gain distribution can be optimized along ultra-long fiber link, due to combination of the 2nd-order RFL and low-noise 1st-order pumping, making the transmission distance be extended significantly. We utilized such a configuration to achieve ultra-long-distance distributed sensing based on Brillouin optical time-domain analysis (BOTDA). A repeater-less sensing distance record of up to 154.4 km with 5 m spatial resolution and ~ ± 1.4 °C temperature uncertainty is successfully demonstrated.
Related JoVE Video
[Histological observations of Medaka(Oryzias latipes)gonad sexual differentiation and development].
Zool. Res.
PUBLISHED: 10-12-2013
Show Abstract
Hide Abstract
Over the past few decades, Medaka (Oryzias latipes) has become a model animal in teleost species research due both to its short reproductive cycle and efficient proliferate capacity. Unfortunately, however, systematic data of its sexual differentiation and development have yet to be obtained. In the present study, we observed Medaka gonad development from the earliest recognizable stages through differentiation to maturation under a light microscope, after paraffin sectioning and hematoxylin-eosin staining. The results showed that among juveniles aged 5 to 10 days, the gonad located on the right side of the dorsal abdominal cavity and the germ cells was significantly larger than the surrounding somatic cells. Ten days after hatching, sexual differences between females and males became obvious, and germline cysts derived from oogonium division were present in the gonad. At 50 days after hatching, ovarian cavities and mature sperm were observed. Moreover, during the study we also observed the coexistence of two sexual characteristics during a males development. Together, these observations fill current gaps in developmental and genetic biology that will allow a more efficient use of Medaka as an experimental model.
Related JoVE Video
Distributed Raman amplification using ultra-long fiber laser with a ring cavity: characteristics and sensing application.
Opt Express
PUBLISHED: 10-10-2013
Show Abstract
Hide Abstract
Distributed Raman amplification (DRA) based on ultra-long fiber laser (UL-FL) pumping with a ring cavity is promising for repeaterless transmission and sensing. In this work, the characteristics (including gain, nonlinear impairment and noise figure) for forward and backward pumping of the ring-cavity based DRA scheme are fully investigated. Furthermore, as a typical application of the proposed configuration, ultra-long-distance distributed sensing with Brillouin optical time-domain analysis (BOTDA) over 142.2 km fiber with 5m spatial resolution and ± 1.5 °C temperature uncertainty is achieved, without any repeater. The key point for the significant performance improvement is the system could offer both of uniform gain distribution and considerably suppressed pump-probe relative intensity noise (RIN) transfer, by optimized design of system structure and parameters.
Related JoVE Video
Organocatalyzed asymmetric synthesis of dihydrodibenzofurans based on a dienamine process.
Org. Lett.
PUBLISHED: 09-16-2013
Show Abstract
Hide Abstract
The first organocatalyzed asymmetric method for the synthesis of dihydrodibenzofurans based on a dienamine process has been developed. This two-step protocol works with a broad range of substrates and delivers only the cis-diastereomer in good yield with up to 91% ee. The enantioenriched products have been transformed to highly functionalized and partially hydrogenated dibenzofurans in excellent diastereoselectivities.
Related JoVE Video
Identification of novel ?-n-methylation of CENP-B that regulates its binding to the centromeric DNA.
J. Proteome Res.
PUBLISHED: 08-26-2013
Show Abstract
Hide Abstract
The eukaryotic centromere is an essential chromatin region required for accurate segregation of sister chromatids during cell division. Centromere protein B (CENP-B) is a highly conserved protein which can bind to the 17-bp CENP-B box on the centromeric DNA. In this study, we found that CENP-B could be ?-N-methylated in human cells. We also showed that the level of the ?-N-methylation was stimulated in cells in response to a variety of extracellular stimuli, including increased cell density, heat shock, and arsenite treatment, although the methylation level was not altered upon metaphase arrest. We identified N-terminal RCC1 methyltransferase (NRMT) as a major enzyme required for the CENP-B methylation. Additionally, we found that chromatin-bound CENP-B was primarily trimethylated and ?-N-trimethylation could enhance CENP-Bs binding to CENP-B box in cells. Our study also expands the function of protein ?-N-methylation that has been known for decades and whose function remains largely unexplored.
Related JoVE Video
Neuroimaging characteristics of MRI-negative orbitofrontal epilepsy with focus on voxel-based morphometric MRI postprocessing.
Epilepsia
PUBLISHED: 08-20-2013
Show Abstract
Hide Abstract
The orbitofrontal (OF) region is one of the least explored regions of the cerebral cortex. There are few studies on patients with electrophysiologically and surgically confirmed OF epilepsy and a negative magnetic resonance imaging (MRI) study. We aimed to examine the neuroimaging characteristics of MRI-negative OF epilepsy with the focus on a voxel-based morphometric MRI postprocessing technique.
Related JoVE Video
[A retrospective analysis of 97 drunk driving cases].
Fa Yi Xue Za Zhi
PUBLISHED: 08-13-2013
Show Abstract
Hide Abstract
Based on a retrospective analysis of the drunk driving cases, to explore the drunk drivers personnel composition, occurrence time and psychology.
Related JoVE Video
Growth regulation, imprinting, and epigenetic transcription-related gene expression differs in lung of deceased transgenic cloned and normal goats.
Theriogenology
PUBLISHED: 08-05-2013
Show Abstract
Hide Abstract
Somatic cell nuclear transfer (SCNT) is a promising technique to produce mammalian transgenic clones. Only a small proportion of manipulated embryos, however, can develop into viable offspring. The abnormal growth and development of cloned animals, furthermore, are accompanied by aberrant lung development. Our objective was to investigate molecular background of lung developmental problems in transgenic (random insertion of exogenous DNA) cloned goats. We examined expression of 15 genes involved in growth regulation, imprinting, and epigenetic transcription in lung tissue of deceased transgenic cloned and normal goats of various ages. Compared with normal goats of the same age from conventional reproduction, expression of 13 genes (BMP4, FGF10, GHR, HGFR, PDGFR, RABP, VEGF, H19, CDKNIC, PCAF, MeCP2, HDAC1, and Dnmt3b) decreased in transgenic cloned goats that died at or shortly after birth; Expression of eight genes (FGF10, PDGFR, RABP, VEGF, PCAF, HDAC1, MeCP2, and Dnmt3b) decreased in fetal death of transgenic cloned goats. Expression of two epigenetic transcription genes (PCAF and Dnmt3b) decreased in disease death of transgenic cloned goats (1-4 months old). Disruptions in gene expression might be associated with the high neonatal mortality in transgenic cloned animals. These findings have implications in understanding the low efficiency of transgenic cloning.
Related JoVE Video
Tetrandrine, an antihypertensive alkaloid, improves the sleep state of spontaneously hypertensive rats (SHRs).
J Ethnopharmacol
PUBLISHED: 07-15-2013
Show Abstract
Hide Abstract
Radix of Stephania tetrandrae S. Moore has been used since antiquity in China as an antirheumatic, antihypertension, analgesic and antipyretic agent. Tetrandrine is the major component of Stephania tetrandrae. This study aims to evaluate the antihypertensive and hypnotic effect of tetrandrine on spontaneously hypertensive rats (SHR) and the possible mechanisms.
Related JoVE Video
Is Dor fundoplication optimum after laparoscopic Heller myotomy for achalasia? A meta-analysis.
World J. Gastroenterol.
PUBLISHED: 07-14-2013
Show Abstract
Hide Abstract
To compare the outcome of acid reflux prevention by Dor fundoplication after laparoscopic Heller myotomy (LHM) for achalasia.
Related JoVE Video
Generation of nondiffracting Bessel beam using digital micromirror device.
Appl Opt
PUBLISHED: 07-12-2013
Show Abstract
Hide Abstract
We experimentally demonstrated Bessel-like beams utilizing digital micromirror device (DMD). DMD with images imitating the equivalent axicon can shape the collimated Gaussian beam into Bessel beam. We reconstructed the 3D spatial field of the generated beam through a stack of measured cross-sectional images. The output beams have the profile of Bessel function after intensity modulation, and the beams extend at least 50 mm while the lateral dimension of the spot remains nearly invariant. Furthermore, the self-healing property has also been investigated, and all the experimental results agree well with simulated results numerically calculated through beam propagation method. Our observations demonstrate that the DMD offers a simple and efficient method to generate Bessel beams with distinct nondiffracting and self-reconstruction behaviors. The generated Bessel beams will potentially expand the applications to the optical manipulation and high-resolution fluorescence imaging owing to the unique nondiffracting property.
Related JoVE Video
[Treatment of diabetic foot by clearing heat, detoxification, activating blood, and dredging collaterals method].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 07-12-2013
Show Abstract
Hide Abstract
To study the mechanism of treating diabetic foot by clearing heat, detoxification, activating blood, and dredging collaterals method.
Related JoVE Video
Is prophylactic somatostatin effective to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis or hyperamylasemia? A randomized, placebo-controlled pilot trial.
Chin. Med. J.
PUBLISHED: 07-05-2013
Show Abstract
Hide Abstract
Effects of prophylactic somatostatin on post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) and hyperamylasemia remain inconclusive. This study aimed to examine whether high-dose, long-term continuous infusion of somatostatin can reduce the incidence of PEP and post-ERCP hyperamylasemia.
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.