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Find video protocols related to scientific articles indexed in Pubmed.
Fractional extreme value adaptive training method: fractional steepest descent approach.
IEEE Trans Neural Netw Learn Syst
PUBLISHED: 03-21-2015
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The application of fractional calculus to signal processing and adaptive learning is an emerging area of research. A novel fractional adaptive learning approach that utilizes fractional calculus is presented in this paper. In particular, a fractional steepest descent approach is proposed. A fractional quadratic energy norm is studied, and the stability and convergence of our proposed method are analyzed in detail. The fractional steepest descent approach is implemented numerically and its stability is analyzed experimentally.
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Surgical treatment and clinical outcome of nonfunctional pancreatic neuroendocrine tumors: a 14-year experience from one single center.
Medicine (Baltimore)
PUBLISHED: 11-15-2014
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Our primary aim of the present study was to analyze the clinical characteristics and surgical outcome of nonfunctional pancreatic neuroendocrine tumors (non-F-P-NETs), with an emphasis on evaluating the prognostic value of the newly updated 2010 grading classification of the World Health Organization (WHO).Data of 55 consecutive patients who were surgically treated and pathologically diagnosed as non-F-P-NETs in our single institution from January 2000 to December 2013 were retrospectively collected.This entirety comprised of 55 patients (31 males and 24 females), with a mean age of 51.24?±?12.95 years. Manifestations of non-F-P-NETs were nonspecific. Distal pancreatectomy, pancreaticoduodenectomy, and local resection of pancreatic tumor were the most frequent surgical procedures, while pancreatic fistula was the most common but acceptable complication (30.3%). The overall 5-year survival rate of this entire cohort was 41.0%, with a median survival time of 60.4 months. Patients who underwent R0 resections obtained a better survival than those who did not (P?
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A droplet microfluidic approach to single-stream nucleic acid isolation and mutation detection.
Microfluid Nanofluidics
PUBLISHED: 11-12-2014
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In this work, a droplet microfluidic platform for genetic mutation detection from crude biosample is described. Single-stream integration of nucleic acid isolation and amplification is realized on a simple fluidic cartridge. Subsequent DNA melting curve is employed with signal normalizing algorithm to differentiate heterozygous K-ras codon 12 c.25G>A mutant from the wildtype. This technique showcases an alternative to modular bench-top approaches for genetic mutation screening, which is of interest to decentralized diagnostic platforms.
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Ischemic stroke associated with immune thrombocytopenia.
J. Thromb. Thrombolysis
PUBLISHED: 11-09-2014
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The objective of this study was to review all cases in literature in which the clinical manifestations of ischemic stroke and immune thrombocytopenia (ITP) were presented in the same patient including a new case of our own and discuss the possible mechanism and management of this syndrome. We reviewed 12 reports in which 18 cases were diagnosed as ischemic stroke and ITP. The clinical manifestations and ischemic lesion patterns of the 18 cases and our new case were analyzed in detail to elucidate the characteristics and management of this kind of syndrome. Of all the cases, 8 females and 10 males, 10 of them were Koreans; 3 were Americans; 3 were Japanese; 1 was British and 1 was Australian. The age of eight patients was no more than 50 years old. Most of them had a low platelet count. CT and/or MRI of brain were seen in all tested cases. Prognosis of ischemic stroke was good in 18 of the 19 patients. Although extremely rare, ischemic stroke and ITP may present in the same patient with variant characteristics. This paradoxical mechanism and management of ischemic stroke associated with ITP requires further investigation.
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Increased Pain Sensitivity in Chronic Pain Subjects on Opioid Therapy: A Cross-Sectional Study Using Quantitative Sensory Testing.
Pain Med
PUBLISHED: 11-08-2014
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The aim of this study was to compare the sensitivity to experimental pain of chronic pain patients on opioid therapy vs chronic pain patients on non-opioid therapy and healthy subjects by quantitative sensory testing (QST).
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The immunologic and hematopoietic profiles of mesenchymal stem cells derived from different sections of human umbilical cord.
Acta Biochim. Biophys. Sin. (Shanghai)
PUBLISHED: 11-05-2014
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Mesenchymal stem cells (MSCs) have been widely used in allogeneic stem cell transplantation. We compared immunologic and hematopoietic characteristics of MSCs derived from whole human umbilical cord (UC), as well as from different sections of UCs, including the amniotic membrane (AM), Wharton's jelly (WJ), and umbilical vessel (UV). Cell phenotypes were examined by flow cytometry. Lymphocyte transformation test and mixed lymphocyte reaction were performed to evaluate the immuno-modulatory activity of MSCs derived from UCs. The mRNA expression of cytokines was detected by real-time polymerase chain reaction. Hematopoietic function was studied by co-culturing MSCs with CD34(+) cells isolated from cord blood. Our results showed that MSCs separated from these four different sections including UC, WJ, UV, and AM had similar biological characteristics. All of the MSCs had multi-lineage differentiation ability and were able to differentiate into osteoblasts, adipocytes, and chondrocytes. The MSCs also inhibited the proliferation of allogeneic T cells in a dose-dependent manner. The relative mRNA expression of cytokines was examined, and the results showed that UCMSCs had higher interleukin-6 (IL6), IL11, stem cell factor, and FLT3 expression than MSCs derived from specific sections of UCs. CD34(+) cells had high propagation efficiencies when co-cultured with MSCs derived from different sections of UCs, among which UCMSCs are the most efficient feeding layer. Our study demonstrated that MSCs could be isolated from whole UC or specific sections of UC with similar immunomodulation and hematopoiesis supporting characteristics.
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Energy metabolism targeted drugs synergize with photodynamic therapy to potentiate breast cancer cell death.
Photochem. Photobiol. Sci.
PUBLISHED: 11-03-2014
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Malignant cells are highly dependent on aerobic glycolysis, which differs significantly from normal cells (the Warburg effect). Interference of this metabolic process has been considered as an innovative method for developing selective cancer therapy. A recent study demonstrated that the glycolysis inhibitor 2-deoxyglucose (2-DG) can potentiate PDT efficacy, whereas the possible mechanisms have not been carefully investigated. This study firstly proved the general potentiation of PDT efficacy by 2-DG and 3-bromopyruvate (3-BP) in human breast cancer MDA-MB-231 cells, and carefully elucidated the underlying mechanism in the process. Our results showed that both 2-DG and 3-BP could significantly promote a PDT-induced cell cytotoxic effect when compared with either monotherapy. Synergistic potentiation of mitochondria- and caspase-dependent cell apoptosis was observed, including a mitochondrial membrane potential (MMP) drop, Bax translocation, and caspase-3 activation. Besides, ROS generation and the expression of oxidative stress related proteins such as P38 MAPK phosphorylation and JNK phosphorylation were notably increased after the combined treatments. Moreover, when pretreated with the ROS scavenger N-acetylcysteine (NAC), the ROS generation, the MMP drop, cell apoptosis and cytotoxicity were differently inhibited, suggesting that ROS was vertical in the pro-apoptotic process induced by 2-DG/3-BP combined with PDT treatment. These results indicate that the combination of glycolytic antagonists and PDT may be a promising therapeutic strategy to effectively kill cancer cells.
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Lack of Effect of Risperidone on Core Autistic Symptoms: Data from a Longitudinal Study.
J Child Adolesc Psychopharmacol
PUBLISHED: 10-31-2014
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Abstract Objective: The purpose of this study was to investigate the course of autistic symptoms, using a quantitative measure of core autistic traits, among risperidone-treated children who participated in a 10 year life course longitudinal study. Methods: Parents completed surveys of intervention history, as well as serial symptom severity measurements using the Social Responsiveness Scale (SRS), on their autism spectrum disorder (ASD)-affected children. Fifty participants (out of a total of 184 with full intervention histories) were reported to have been treated with risperidone during the course of the study. Serial SRS scores during risperidone treatment were available for a majority of children whose parents reported a positive effect from risperidone. Results: Two thirds of risperidone-treated children (n=33) were reported by parents to have improved by taking the medication, with the principal effects described being that children were calmer, better focused, and less aggressive. SRS scores of children reported to have responded positively to risperidone did not improve over time. Conclusions: Risperidone's beneficial effect on aggression and other elements of adaptive functioning were not necessarily accompanied by reduction in core ASD symptoms, as serially assessed by the same caregivers who reported improvement in their children. These results reflect the distinction between reduction in core symptom burden and improvement in adaptive functioning. Given the cumulative risks of atypical neuroleptics, the findings underscore the importance of periodic re-evaluation of medication benefit for children with ASD receiving neuroleptic treatment.
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Sensitive impedimetric biosensor based on duplex-like DNA scaffolds and ordered mesoporous carbon nitride for silver(i) ion detection.
Analyst
PUBLISHED: 10-28-2014
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This study demonstrates a new, unlabeled immobilized DNA-based biosensor with ordered mesoporous carbon nitride material (MCN) for the detection of Ag(+) by electrochemical impedance spectroscopy (EIS) with [Fe(CN)6](4-/3-) as the redox couple. The unlabeled immobilized DNA initially formed the hairpin-like structure through hybridization with the probe, and then changed to duplex-like structure upon interaction with Ag(+) in solution to form a C-Ag(+)-C complex at electrode surface. As a result, the interfacial charge-transfer resistance of the electrode towards the [Fe(CN)6](4-/3-) redox couple was changed. Thus, a declined charge transfer resistance (Rct) was obtained, corresponding to Ag(+) concentration. MCN provide an excellent platform for DNA immobilization and faster electron transfer. Impedance data were analyzed with the help of Randles equivalent circuit. The lower detection limit of the biosensor for Ag(+) is 5 × 10(-11) M with good specificity. All results showed that this novel approach provides a reliable method for Ag(+) detection with sensitivity and specificity, potentially useful for practical applications. Moreover, other DNA detection methods for more heavy metals may be obtained from this idea and applied in the environmental field.
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[Evaluation on implementation effect of Malaria Elimination Project supported by Global Fund in Shaanxi Province].
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi
PUBLISHED: 10-28-2014
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To evaluate the implementation effect of Malaria Elimination Project supported by the Global Fund in Shaanxi Province so as to provide the evidence for the scientific implementation of Malaria Elimination Action Plan and the examination and evaluation work.
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Multiplexed microfluidic blotting of proteins and nucleic acids by parallel, serpentine microchannels.
Lab Chip
PUBLISHED: 10-25-2014
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This work develops a high-throughput, high-efficiency and straightforward microfluidic blotting method for analyzing proteins and nucleic acids. Sample solutions containing antibodies (for protein detection) or hybridization probes (for nucleic acid detection) are introduced into the parallel, serpentine microchannels to specifically recognize the immobilized targets on the substrate, achieving the identification of multiple targets in multiple samples simultaneously. The loading control, molecular weight markers, and antigen/antibody titration are designed and integrated into the microfluidic chip, thus allowing for the quantification of proteins and nucleic acids. Importantly, we could easily distinguish the adjacent blotting bands inside parallel microchannels, which may be difficult to achieve in conventional blotting. The small dimensions of microfluidic channels also help to reduce the amount of probing molecules and to accelerate the biochemical reaction. Our microfluidic blotting could bypass the steps of blocking and washing, further reducing the operation time and complexity.
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Study on the effect of vacuum sealing drainage on the repair process of rabbit sciatic nerve injury.
Int. J. Neurosci.
PUBLISHED: 10-24-2014
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Purpose: To investigate the influence of vacuum sealing drainage on sciatic nerve repair after injury in rabbits. Materials and Methods: Twenty four New Zealand white rabbits were randomly divided into experimental group and control group. About 1 cm sciatic nerve was transected and sutured back in situ. The experimental group had vacuum sealing drainage assisted wound closure whereas the control group had normal wound closure. The nerve repair rate was compared based on nerve conduction velocity, lower leg triceps wet weight recovery rate, histology, immunohistochemical of brain-derived neurotrophic factor, and ultrastructure observation of regenerated nerve by electron microscopy at the 4th and 8th week after surgery. Results: At the 1st-2nd weeks after surgery, irritation and ulcers were observed on the surgical side in both the experimental group and the control group. At the 4th and 8th week after surgery, electrical nerve conduction velocity in the experimental group was faster than in the control group (p < 0.05) and triceps muscle calf wet weight recovery rate in the experimental group was higher than that in the control group (p < 0.05). Brain-derived neurotrophic factor immunohistochemical staining intensity in the experimental group was higher than that in the control group (p < 0.05) and toluidine blue staining and electron microscopic observation showed that the nerve regeneration and repair were more pronounced in the experimental group as compared to the control group. Myelinated nerve fibers in the experimental group were more than that in the control group at the 4th week and 8th week after surgery. Conclusion: Vacuum sealing drainage facilitates repair of peripheral nerve injury.
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[Construction of Mouse VCAM-1 Expression Vector and Establishment of Stably Transfected MSC Line C3H10T1/2].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 10-24-2014
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This study was aimed to construct the mouse VCAM-1 expression vector, to establish the stably transfected MSC line and to investigate the effect of VCAM-1-modified mesenchymal stem cells (MSC) on the immunological characteristics of MSC. The cDNA of murine VCAM-1 gene was amplified by RT-PCR from the total RNA isolated from the mouse spleen; then the cDNA was inserted into the retrovirus vector PMSCVmigr-1; the recombinant plasmid was confirmed by restriction endonuclease experiments and sequencing, then designated as PMSCVmigr-1-mVCAM-1; the recombinant plasmid PMSCVmigr-1-mVCAM-1 was transfected into 293 cells by lipofecamin and the supernatant was collected to transfect MSC cell line (C3H10T1/2). Moreover, VCAM-1 expression on MSC was evaluated by FACS. Furthermore, the inhibitory effect of VCAM-1-MSC on lymphocytic transformation was tested by (3)H-TdR incorporation assay. The results indicated that the successful construction of recombinant retroviral expression plasmid of mouse VCAM-1 was confirmed by digesting and sequancing. After transfection of MSC with retroviral supernaptant, the high expression of VCAM-1 on MSC could be detected by flow cytometry. The MSC high expressing VCAM-1 could significantly inhibit the proliferation of Con A-inducing lymphocytes in dose-depentent marrer. It is concluded that recombinant retroviral encoding VCAM-1 (PMSCVmigr-1-mVCAM-1) has been successfully constructed and mouse VCAM-1 has been stably expressed in C3H10T1/2. MSC over-expressing VCAM-1 show more potent immunosuppressive effect on cellular immune reaction in vitro. Our data laid a foundation for the subsequent studying the effect of VCAM-1 transfecting into MSC on immune related disease study.
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[Influence of donor mouse age on the establishment of murine acute graft versus host disease model after allogenic hematopoietic stem cell transplantation].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 10-24-2014
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This study was purposed to elucidate the influence of donor mouse age on the establishment of murine acute graft versus host disease (aGVHD) model after allogenic hematopoietic stem cell transplantation. The male mice with 2-week-old, 10-week-old and 18-week-old mice (BALB/cH-2Kb) were taken as donors. The 8-week-old mice (BALB/c, H-2Kd) were selected as recipients. Each group animals were irradiated with 7.5 Gy (60)Co for total body, the recipient mice were injected intravenously with 1×10(7) bone marrow cells and 1×10(7) spleenoctyes from various donors in 4-5 hours after irradiation. Mouse transplant characteristics and survival were observed every day. The white blood cell number in peripheral blood of each group were counted at day 5, 10, 15, 20, 25 and 30 after transplantation. Furthermore, the pathological damage in the liver, spleen, lung and intestines were evaluated by sectioning and in situ hematoxylin-eosin (HE) staining. The results showed that compared with the 2-week-old and 10-week-old donor groups, mice received bone marrow (BM) cells and splenocytes from 18-week-old mice showed higher incidence of aGVHD, lower clinical GVHD scores and suffered from diarrhea, ruffled hair, a hunched posture, and diminished body weight. In contrast, mice received BM cells and splenocytes from 2-week-old donor mice indicated attenuated GVHD symptoms and survived longer. The histo-pathological analysis in 18-week-old donor group demonstrated the most serious pathological damage in the liver, spleen, lung and intestines. It is concluded that the donor age has been confired to have an obvious influence on the establishment of murine aGVHD model. This study lay an important foundation for establishing animal models and may be helpful for further study.
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Proteomic Investigation of Signatures for Geniposide-Induced Hepatotoxicity.
J. Proteome Res.
PUBLISHED: 10-23-2014
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Evaluating the safety of traditional medicinal herbs and their major active constituents is critical for their widespread usage. Geniposide, a major active constituent with a defined structure from the traditional medicinal herb Gardenia jasminoides ELLIS fruit, exhibits remarkable anti-inflammatory, antiapoptotic, and antifibrotic properties and has been used in a variety of medical fields, mainly for the treatment of liver diseases. However, geniposide-induced hepatotoxicity and methods for the early detection of hepatotoxicity have yet to be reported. In this study, geniposide-induced hepatotoxicity was investigated. In addition, candidate biomarkers for the earlier detection of geniposide-induced hepatotoxicity were identified using a label-free quantitative proteomics approach on a geniposide overdose-induced liver injury in a rat model. Using an accurate intensity-based, absolute quantification (iBAQ)-based, one-step discovery and verification approach, a candidate biomarker panel was easily obtained from individual samples in response to different conditions. To determine the biomarkers' early detection abilities, five candidate biomarkers were selected and tested using enzyme-linked immunosorbent assays (ELISAs). Two biomarkers, glycine N-methyltransferase (GNMT) and glycogen phosphorylase (PYGL), were found to indicate hepatic injuries significantly earlier than the current gold standard liver biomarker. This study provides a first insight into geniposide-induced hepatotoxicity in a rat model and describes a method for the earlier detection of this hepatotoxicity, facilitating the efficient monitoring of drug-induced hepatotoxicity.
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[Population characteristics and ecological suitability of Saussureae hieracioides].
Zhong Yao Cai
PUBLISHED: 10-23-2014
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To analyze the population characteristics and the appropriate producing area of Saussureae hieracioides in China.
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Enhanced photoproduction of hydrogen peroxide by humic substances in the presence of phenol electron donors.
Environ. Sci. Technol.
PUBLISHED: 10-22-2014
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Addition of a series of phenol electron donors to solutions of humic substances (HS) enhanced substantially the initial rates of hydrogen peroxide (H2O2) photoproduction (RH2O2), with enhancement factors (EF) ranging from a low of ?3 for 2,4,6-trimethylphenol (TMP) to a high of ?15 for 3,4-dimethoxyphenol (DMOP). The substantial inhibition of the enhanced RH2O2 following borohydride reduction of the HS, as well as the dependence of RH2O2 on phenol and dioxygen concentrations are consistent with a mechanism in which the phenols react with the triplet excited states of (aromatic) ketones within the HS to form initially a phenoxy and ketyl radical. The ketyl radical then reacts rapidly with dioxygen to regenerate the ketone and form superoxide (O2(-)), which subsequently dismutates to H2O2. However, as was previously noted for the photosensitized loss of TMP, the incomplete inhibition of the enhanced RH2O2 following borohydride reduction suggests that there may remain another pool of oxidizing triplets. The results demonstrate that H2O2 can be generated through an additional pathway in the presence of sufficiently high concentrations of appropriate electron donors through reaction with the excited triplet states of aromatic ketones and possibly of other species such as quinones. However, in some cases, the much lower ratio of H2O2 produced to phenol consumed suggests that secondary reactions could alter this ratio significantly.
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[(99m)Tc]cFLFLF for Early Diagnosis and Therapeutic Evaluation in a Rat Model of Acute Osteomyelitis.
Mol Imaging Biol
PUBLISHED: 10-18-2014
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Early diagnosis and therapeutic monitoring of acute osteomyelitis (AO) is challenging. Here, we use a polyethylene glycol (PEG)ylated chemotactic peptide cinnamoyl-F-(D)L-F-(D)L-F (cFLFLF) conjugated with hydrazinonicotinamide (HYNIC) and labeled with Tc-99m ([(99m)Tc]cFLFLF) to image AO in a rat model and to validate its efficacy in early diagnosis and therapeutic evaluation of AO.
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Integrated analysis reveals that STAT3 is central to the crosstalk between HER/ErbB receptor signaling pathways in human mammary epithelial cells.
Mol Biosyst
PUBLISHED: 10-16-2014
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Human epidermal growth factor receptors (HER, also known as ErbB) drive cellular proliferation, pro-survival and stress responses by activating several downstream kinases, in particular ERK, p38 MAPK, JNK (SAPK), the PI3K/AKT, as well as various transcriptional regulators such as STAT3. When co-expressed, the first three members of HER family (HER1-3) can form homo- and hetero-dimers, and there is considerable evidence suggesting that the receptor dimers differentially activate intracellular signaling pathways. To better understand the interactions in this system, we pursued multi-factorial experiments where HER dimerization patterns and signaling pathways were rationally perturbed. We measured the activation of HER1-3 receptors and of the sentinel signaling proteins ERK, AKT, p38 MAPK, JNK, STAT3 as a function of time in a panel of human mammary epithelial (HME) cells expressing different levels of HER1-3 stimulated with various ligand combinations. We hypothesized that the HER dimerization pattern is a better predictor of downstream signaling than the total receptor activation levels. We validated this hypothesis using a combination of model-based analysis to quantify the HER dimerization patterns, and by clustering the activation data in multiple ways to confirm that the HER receptor dimer is a better predictor of the signaling through p38 MAPK, ERK and AKT pathways than the total HER receptor expression and activation levels. We then pursued combinatorial inhibition studies to identify the causal regulatory interactions between sentinel signaling proteins. Quantitative analysis of the collected data using the modular response analysis (MRA) and its Bayesian Variable Selection Algorithm (BVSA) version allowed us to obtain a consensus regulatory interaction model, which revealed that STAT3 occupies a central role in the crosstalk between the studied pathways in HME cells. Results of the BVSA/MRA and cluster analysis were in agreement with each other.
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A novel MEMS compatible lab-on-a-tube technology.
Lab Chip
PUBLISHED: 10-15-2014
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We present a novel lab-on-a-tube technology, which is a combination of three-dimensional (3D) cylindrical photolithography and nanoimprint processes, for fabricating microfunctional structures on a tiny tube substrate directly. As an example, electrochemical electrodes, which consisted of Pt work and Ag/AgCl reference electrodes, were successfully fabricated on a 330-?m-diameter polyimide capillary. Using thermal nanoimprint technology, a microdome array with a diameter of 2 ?m to about 600 nm was prepared in the work and reference electrodes. The nanoimprinted domes greatly enhanced the electrochemical activity and there were much higher oxidation and reduction current peaks observed in cyclic voltammetry curves of the nanoimprinted electrode than those of the blank electrode without the nanoimprint modification. The nanoimprinted patterns exhibited complicated effects, e.g. the 600-nm-diameter dome sample has higher electrochemical activity than the 2-?m-diameter dome, while the latter has a larger surface. By using the new lab-on-a-tube technology, new bio- and nanomaterials could be integrated directly into electronic devices on tiny tube substrates so that many interesting applications could be expected in medical and life technologies.
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The Noninvasive Detection of RAR?2 Promoter Methylation for the Diagnosis of Prostate Cancer.
Cell Biochem. Biophys.
PUBLISHED: 10-14-2014
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Prostate cancer is a kind of commonly diagnosed male malignancy. With the aging population in China, both incidence and mortality of prostate cancer are expected to keep increasing in the future. The methylation of RAR?2 gene promoter is a common molecular event in prostate cancer. Thus, we aimed at establishing a high-performance noninvasive DNA methylation assay based on pyrosequencing for screening of prostate cancer in this article. The assay is designed to detect aberrant promoter methylation of RAR?2 gene in ejaculate samples. The negative and positive control plasmids were constructed with different treatments by direct bisulfite conversion or conversion after Sss I Methylase methylation to establish quality control standard. The ejaculate and tissue samples were collected from patients with histologically confirmed adenocarcinoma of prostate (n = 43) and benign prostatic hyperplasia (n = 40). Significant correlation was observed between prostate cancer and methylation level of RAR?2 gene promoter. In addition, the results of pyrosequencing in ejaculate samples were compared with that of DNA sequencing in tissue samples from the same patients. There is no significant difference in the detection of RAR?2 promotor methylation between these two methods (p < 0.05). In conclusion, we have developed a high-performance noninvasive DNA methylation assay based on pyrosequencing which is more suitable for high-throughput detection of aberrant promoter methylation in ejaculate samples. Moreover, the acceptive degree of this noninvasive method makes it potentially promising for future screening of prostate cancer.
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Temperature-Triggered Reversible Dielectric and Nonlinear Optical Switch Based on the One-Dimensional Organic-Inorganic Hybrid Phase Transition Compound [C6H11NH3]2CdCl4.
Inorg Chem
PUBLISHED: 10-03-2014
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The one-dimensional organic-inorganic hybrid compound bis(cyclohexylammonium) tetrachlorocadmate(II) (1), in which the adjacent infinite [CdCl4]n(-) chains are connected to each other though Cd···Cl weak interactions to form perovskite-type layers of corner-sharing CdCl6 octahedra separated by cyclohexylammonium cation bilayers, was synthesized. It undergoes two successive structural phase transitions, at 215 and 367 K, which were confirmed by systematic characterizations including differential scanning calorimetry (DSC) measurements, variable-temperature structural analyses, and dielectric and second harmonic generation (SHG) measurements. A precise structural analysis discloses that the phase transition at 215 K is induced by the disorder-order transition of cyclohexylammonium cations, while the phase transition at 367 K derives from changes in the relative location of Cd atoms. Emphatically, both the dielectric constant and SHG intensity of 1 show a striking change between low and high states at around 367 K, which reveals that 1 might be considered as a potential dielectric and nonlinear optical (NLO) switch with high-temperature response characterization, excellent reversibility, and obvious change of states.
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Integrated Microcapillary for Sample-to-Answer Nucleic Acid Pretreatment, Amplification, and Detection.
Anal. Chem.
PUBLISHED: 10-02-2014
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This work develops an integrated microcapillary-based loop-mediated isothermal amplification (icLAMP) containing preloaded reagents and DNA extraction card, allowing for sample-to-answer screening of single nucleotide polymorphisms (SNPs) typing of the CYP2C19 gene from untreated blood samples with minimal user operation. With all reagents and the DNA extraction card preloaded inside the capillary, this icLAMP system can achieve on-site pretreatment, extraction, amplification, and detection of nucleic acids within 150 min, without the requirement for advanced instruments. As icLAMP technology carries many advantages such as disposability, easy operation, low cost, and reduced cross contamination and biohazard risks, we expect this system to have a great impact on point-of-care (POC) nucleic acid detection.
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Inactivation of dinoflagellate Scripsiella trochoidea in synthetic ballast water by advanced oxidation processes.
Environ Technol
PUBLISHED: 09-30-2014
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Ship-borne ballast water contributes significantly to the transfer of non-indigenous species across aquatic environments. To reduce the risk of bio-invasion, ballast water should be treated before discharge. In this study, the efficiencies of several conventional and advanced oxidation processes were investigated for potential ballast water treatment, using a marine dinoflagellate species, Scripsiella trochoidea, as the indicator organism. A stable and consistent culture was obtained and treated by ultraviolet (UV) light, ozone (O3), hydrogen peroxide (H2O2), and their various combinations. UV apparently inactivated the cells after only 10?s of irradiation, but subsequently photo-reactivation of the cells was observed for all methods involving UV. O3 exhibited 100% inactivation efficiency after 5?min treatment, while H2O2 only achieved maximum 80% inactivation in the same duration. Combined methods, e.g. UV/O3 and UV/H2O2, were found to inhibit photo-reactivation and improve treatment efficiency to some degree, indicating the effectiveness of using combined treatment processes. The total residual oxidant (TRO) levels of the methods were determined, and the results indicated that UV and O3 generated the lowest and highest TRO, respectively. The synergic effect of combined processes on TRO generation was found to be insignificant, and thus UV/O3 was recommended as a potentially suitable treatment process for ballast water.
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Wound Documentation by Using 3G Mobile as Acquisition Terminal: An Appropriate Proposal for Community Wound Care.
Int J Low Extrem Wounds
PUBLISHED: 09-27-2014
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The increasing numbers of cases of wound disease are now posing a big challenge in China. For more convenience of wound patients, wound management in community health care centers under the supervision of a specialist at general hospitals is an ideal solution. To ensure an accurate diagnosis in community health clinics, it is important that "the same language" for wound description, which may be composed of unified format description, including wound image, must be achieved. We developed a wound information management system that was built up by acquisition terminal, wound description, data bank, and related software. In this system, a 3G mobile phone was applied as acquisition terminal, which could be used to access to the data bank. This documentation system was thought to be an appropriate proposal for community wound care because of its objectivity, uniformity, and facilitation. It also provides possibility for epidemiological study in the future.
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[The influence of the single different radiation dose and time on the microscopic structure and ultrastructure of Balb/c mice].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 09-25-2014
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To observe the influence of the single different radiation dose and time on the microscopic structure and ultrastructure of Balb/c Mice.
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Resistance to cetuximab in EGFR-overexpressing esophageal squamous cell carcinoma xenografts due to FGFR2 amplification and overexpression.
J. Pharmacol. Sci.
PUBLISHED: 09-23-2014
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Esophageal carcinoma is one of the most virulent malignant diseases and a major cause of cancer-related deaths worldwide. Despite improvements in surgical techniques and perioperative management and surgery combined with chemotherapy and/or radiotherapy, the prognosis of esophageal squamous cell carcinoma (ESCC) at an advanced stage remains poor. ESCC shows a relatively high incidence of EGFR (50% - 70%), and the humanized monoclonal antibody (mAb) cetuximab against EGFR has been undergoing clinical development. However, all responding patients eventually developed acquired resistance to cetuximab. In the current study, we described a cetuximab-sensitive ESCC xeongraft model that developed resistance to cetuximab as a result of FGFR2 gene amplification and overexpression. Inhibition of FGFR2 signaling in this xenograft model restored its sensitivity to cetuximab. The antitumor effect may be induced by inhibition of AKT phosphorylation. These findings suggest that combination therapyincluding cetuximab and FGFR2 inhibition may be a promising strategy to treat ESCC.
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CKIP-1 suppresses the adipogenesis of mesenchymal stem cells by enhancing HDAC1-associated repression of C/EBP?.
J Mol Cell Biol
PUBLISHED: 09-19-2014
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Mesenchymal stem cells (MSCs) are considered as the developmental origin of multiple lineage cells including osteocytes, adipocytes, and muscle cells. Previous studies demonstrated that the PH domain-containing protein CKIP-1 plays an important role in the development of osteoblasts and cardiomyocytes. However, whether CKIP-1 is involved in the generation of adipocytes as well as the MSC differentiation remains unknown. Here we show that CKIP-1 is a novel regulator of MSCs differentiating into adipocytes. MSCs derived from CKIP-1-deficient mice display enhanced adipogenesis upon induction. Further analysis showed that CKIP-1 interacts with the histone deacetylase HDAC1 in the nucleus and inhibits the transcription of CCAAT/enhancer-binding protein ? (C/EBP?), which is a crucial adipogenic transcription factor. Ectopic expression of CKIP-1 in a MSC-like cell line C3H/10T1/2 reduced the generation of adipocytes due to suppression of adipogenic factors, including C/EBP?. Moreover, CKIP-1-deficient mice showed an increase in body weight and white adipose tissue gains when fed on a high-fat diet. Collectively, these results suggest that CKIP-1 is a novel inhibitor of MSC-originated adipogenesis by enhancing HDAC1-associated repression of C/EBP?.
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Correlation of fractional anisotropy and metabolite concentrations measured using 1H-MRS of cerebral white matter in healthy adults.
Biomed Mater Eng
PUBLISHED: 09-18-2014
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Fractional anisotropy (FA) is currently an ideal index capable of reflecting the white matter structure. 1H magnetic resonance spectroscopy (1H-MRS) is often used as a noninvasive concentration measurement of important neurochemicals in vivo. This study was conducted to investigate the relationship between FA and metabolite concentrations by comparing 1H-MRS of bilateral medium corona radiata in healthy adults. The data of diffusion tensor imaging (DTI) and 1H-MRS were acquired from 31 healthy adults using a 3.0 T MR system. All subjects were divided into three groups: the total group (mean age=42 years), the junior group (mean age=29 years) and the senior group (mean age=56 years). There was a negative correlation between FA and age in three groups (r=-0.146, r=-0.204, r=-0.162, p<0.05). The positive correlation of FA with corresponding concentrations of N-acetylaspartate (NAA) was significant in three groups (r=0.339, r=0.213, r=0.430, respectively, p<0.05). The positive correlation of FA with the corresponding NAA/Cr was only significant difference between the total 353 samples and the junior group (r=0.166, r=0.305, respectively, p<0.05). Combining 1H-MRS with DTI reveals the relationship between structure and metabolic characteristics of white matter.
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The research of laryngeal joints to reconstruction and modeling.
Biomed Mater Eng
PUBLISHED: 09-18-2014
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Larynx has a complex structure with joints and multiple functions. In order to study the artificial larynx and artificial auricle scaffold, a three-dimensional digital model of laryngeal joint is established in this paper using MIMICS with its biomechanical properties analyzed and calculated by using the finite element method. This model is based on the CT scanned images of 281 layers with an interlamellar spacing of 1.25 mm. The obtained data are denoised, segmented and smoothed before being loaded into MIMICS. By further optimizations, an accurate and complete 3D model can be obtained. Subsequently, a 3D FEM of the normal larynx joint is performed which allows observations from any dimensions and angles. Compared with natural laryngeal joint, this model has good geometric similarity and mechanically similar throat voicing functions.
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[Identification of three common sandfies in southern Xinjiang with multiplex PCR].
Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi
PUBLISHED: 09-17-2014
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Based on the variable part of mtDNA CO I gene sequence, a multiplex PCR method was developed for the identification of the three common sandflies (Phlebotomus longiductus, Ph. wui, and Ph. alexandri) in southern Xinjiang. The results demonstrated that this multiplex PCR method was reliable, and could be used to identify the three Phlebotomus species. The PCR product of CO I gene from Ph. longiductus, Ph. wui and Ph. alexandri was 248, 632, and 395 bp, respectively.
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Role of Tet proteins in enhancer activity and telomere elongation.
Genes Dev.
PUBLISHED: 09-15-2014
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DNA methylation at the C-5 position of cytosine (5mC) is one of the best-studied epigenetic modifications and plays important roles in diverse biological processes. Iterative oxidation of 5mC by the ten-eleven translocation (Tet) family of proteins generates 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC). 5fC and 5caC are selectively recognized and excised by thymine DNA glycosylase (TDG), leading to DNA demethylation. Functional characterization of Tet proteins has been complicated by the redundancy between the three family members. Using CRISPR/Cas9 technology, we generated mouse embryonic stem cells (ESCs) deficient for all three Tet proteins (Tet triple knockout [TKO]). Whole-genome bisulfite sequencing (WGBS) analysis revealed that Tet-mediated DNA demethylation mainly occurs at distally located enhancers and fine-tunes the transcription of genes associated with these regions. Functional characterization of Tet TKO ESCs revealed a role for Tet proteins in regulating the two-cell embryo (2C)-like state under ESC culture conditions. In addition, Tet TKO ESCs exhibited increased telomere-sister chromatid exchange and elongated telomeres. Collectively, our study reveals a role for Tet proteins in not only DNA demethylation at enhancers but also regulating the 2C-like state and telomere homeostasis.
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Predicting subsequent relapse by drug-related cue-induced brain activation in heroin addiction: an event-related functional magnetic resonance imaging study.
Addict Biol
PUBLISHED: 09-13-2014
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Abnormal salience attribution is implicated in heroin addiction. Previously, combining functional magnetic resonance imaging (fMRI) and a drug cue-reactivity task, we demonstrated abnormal patterns of subjective response and brain reactivity in heroin-dependent individuals. However, whether the changes in cue-induced brain response were related to relapse was unknown. In a prospective study, we recruited 49 heroin-dependent patients under methadone maintenance treatment, a gold standard treatment (average daily dose 41.8?±?16.0?mg), and 20 healthy subjects to perform the heroin cue-reactivity task during fMRI. The patients' subjective craving was evaluated. They participated in a follow-up assessment for 3 months, during which heroin use was assessed and relapse was confirmed by self-reported relapse or urine toxicology. Differences between relapsers and non-relapsers were analyzed with respect to the results from heroin-cue responses. Compared with healthy subjects, relapsers and non-relapsers commonly demonstrated significantly increased brain responses during the processing of heroin cues in the mesolimbic system, prefrontal regions and visuospatial-attention regions. However, compared with non-relapsers, relapsers demonstrated significantly greater cue-induced craving and the brain response mainly in the bilateral nucleus accumbens/subcallosal cortex and cerebellum. Although the cue-induced heroin craving was low in absolute measures, the change in craving positively correlated with the activation of the nucleus accumbens/subcallosal cortex among the patients. These findings suggest that in treatment-seeking heroin-dependent individuals, greater cue-induced craving and greater specific regional activations might be related to reward/craving and memory retrieval processes. These responses may predict relapse and represent important targets for the development of new treatment for heroin addiction.
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RLIP76 Blockade by siRNA Inhibits Proliferation, Enhances Apoptosis, and Suppresses Invasion in HT29 Colon Cancer Cells.
Cell Biochem. Biophys.
PUBLISHED: 09-13-2014
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RLIP76, a multidomain protein which is a downstream effector of the small GTP ases RalA and RalB, is known to play a role in biological activities in a variety of malignant cancer cells. However, little study has been done on the role of RLIP76 in CRC. In this study, a RLIP76-targeted siRNA-containing vector was used to investigate the effect of RLIP76 knockdown on cellular functions in human CRC cell line HT29. Quantitative RT-PCR and Western blot analysis revealed that the expression levels of RLIP76 mRNA and protein in HT29 cells were significantly suppressed after transfection. Our results indicated that RLIP76 downregulation in HT29 CRC cells suppressed cell growth, enhanced cell apoptosis, induced cell cycle arrest, and inhibited cell invasion by decreasing MMP2 expression. Although the mechanisms through which RLIP76 regulates the cellular functions needs further investigation, our results indicate that RLIP76 may represent as a potential target of gene therapy for CRC treatment.
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[Analysis on medication regularity of Chinese patent medicines containing Scutellaria baicalensis].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 09-11-2014
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To analyze the composition regularity of prescriptions containing Scutellaria baicalensis in Drug Standard of Ministry of Public Health of the Peoples Republic of China--Chinese Patent Medicines and Preparations on the basis of the traditional Chinese medicine inheritance support system (TCMISS), in order to provide reference for new drug R&D. the platform's software V2.0 was applied to establish a database of prescriptions containing S. baicalensis. The software's statistical statement module, association rules and improved mutual information method and other data mining technologies were adopted to analyze commonly used drugs, combination rules and core combination of S. baicalensis prescriptions. Having analyzed 477 prescriptions containing S. baicalensis, the researchers summarized 45 most commonly used drug combinations, whose ingredients mostly had functions of heat-clearing and damp-drying, purging fire for removing toxin and hemostasis. Drugs adopted in core combinations were relatively concentrated and selected according to definite composition methods. There were 23 diseases that S. baicalensis were most frequently applied in the treatment. Having compared three highly frequent diseases--cold, cough and dizziness, the researchers concluded that S. baicalensis could show different therapeutic effects through different combination ratios. Therefore, TCMISS (V2.0) is an important tool in analyzing the composition regularity of traditional Chinese medicines. The longitudinal and parallel comparison method is an effective method for studying the clinical composition regularity of S. baicalensis, while providing reference for new drug R&D.
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Downregulation of Msi1 suppresses the growth of human colon cancer by targeting p21cip1.
Int. J. Oncol.
PUBLISHED: 09-07-2014
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Musashi1 (Msi1), a member of the RNA-binding protein (RBP) family, is highly expressed in neural progenitor or stem cells for the maintenance of stemness as well as in various cancers. Emerging studies have demonstrated that it regulates cell processes by translational activation or suppresses specifically bound mRNA. In the present study, we initially reported remarkably increased expression of Msi1 in colon cancer tissues compared with adjacent non-tumor tissues. Knockdown of Msi1 significantly suppressed the proliferation, colony formation, tumorsphere formation and the progression of implanted colon cancers, and induced cell cycle attest at G0/G1 phase, along with the upregulated expression of p21cip1. Reporter assays using a chimeric mRNA that combined luciferase and the 3'-UTR of p21cip1 revealed that Msi1 decreased the reporter activity through the specific motif. Thus, the current results suggested that downregulation of Msi1 could inhibit the growth of colon cancers and Msi1 may be a promising therapeutic target molecule for human colon cancers.
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Regulation of Lipogenic Gene Expression by Lysine-specific Histone Demethylase-1 (LSD1).
J. Biol. Chem.
PUBLISHED: 09-04-2014
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Dysregulation of lipid homeostasis is a common feature of several major human diseases, including type 2 diabetes and cardiovascular disease. However, because of the complex nature of lipid metabolism, the regulatory mechanisms remain poorly defined at the molecular level. As the key transcriptional activators of lipogenic genes, such as fatty acid synthase (FAS), sterol regulatory element-binding proteins (SREBPs) play a pivotal role in stimulating lipid biosynthesis. Several studies have shown that SREBPs are regulated by the NAD(+)-dependent histone deacetylase SIRT1, which forms a complex with the lysine-specific histone demethylase LSD1. Here, we show that LSD1 plays a role in regulating SREBP1-mediated gene expression. Multiple lines of evidence suggest that LSD1 is required for SREBP1-dependent activation of the FAS promoter in mammalian cells. LSD1 knockdown decreases SREBP-1a at the transcription level. Although LSD1 affects nuclear SREBP-1 abundance indirectly through SIRT1, it is also required for SREBP1 binding to the FAS promoter. As a result, LSD1 knockdown decreases triglyceride levels in hepatocytes. Taken together, these results show that LSD1 plays a role in regulating lipogenic gene expression, suggesting LSD1 as a potential target for treating dysregulation of lipid metabolism.
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Current concepts in the pathogenesis of traumatic temporomandibular joint ankylosis.
Head Face Med
PUBLISHED: 09-04-2014
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Traumatic temporomandibular joint (TMJ) ankylosis can be classified into fibrous, fibro-osseous and bony ankylosis. It is still a huge challenge for oral and maxillofacial surgeons due to the technical difficulty and high incidence of recurrence. The poor outcome of disease may be partially attributed to the limited understanding of its pathogenesis. The purpose of this article was to comprehensively review the literature and summarise results from both human and animal studies related to the genesis of TMJ ankylosis.
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Systematic review of traditional chinese medicine for depression in Parkinson's disease.
Am. J. Chin. Med.
PUBLISHED: 09-03-2014
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Depression is the most common non-motor symptom of Parkinson's disease (PD). Recent clinical trials have evaluated the effectiveness of traditional Chinese medicine (TCM) in the treatment of depression in PD (dPD). However, the results are conflicting rather than conclusive. To investigate the effectiveness of TCM for the treatment of dPD, a systematic review was conducted. Literature searches and collections were performed to identify studies addressing the treatment of TCM for dPD. The methodological quality and risk of bias in all studies included were evaluated. Weighted mean difference (WMD) with 95% confidence interval (CI) was used as the effect measure. Finally, a total of 10 studies involving 582 patients were identified. The pooled results revealed that TCM combined with conventional drugs significantly improved the total scores of the unified Parkinson's disease rating scale (WMD = -7.35, 95% CI: -11.24 to -3.47) and the score of the Hamilton rating scale for depression (HAM-D) (WMD = -4.19, 95% CI: -5.14 to -3.24) compared with conventional drug, respectively. Conclusively, there is evidence that TCM may be beneficial to the treatment of dPD in spite of the methodological weakness of the included studies.
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Sedentary behaviour and the risk of depression: a meta-analysis.
Br J Sports Med
PUBLISHED: 09-02-2014
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Sedentary behaviour is associated with risk of depression. We review and quantitatively summarise the evidence from observational studies in a meta-analysis.
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New maltol glycosides from Flos Sophorae.
J Nat Med
PUBLISHED: 09-01-2014
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Three new maltol glycosides, designated soyamalosides A (1), B (2), and C (3), together with eight known compounds (4-11), were obtained from a 70 % EtOH extract of Flos Sophorae. Their structures were elucidated by chemical and spectroscopic methods. Of the known compounds, this is the first report of 4-6, 9, and 11 in the Sophora genus. Compounds 2, 3, and 10 showed significant protective effects against antimycin A-induced L6 cell injury.
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The effect of chronic lymphocytic thyroiditis on patients with thyroid cancer.
World J Surg Oncol
PUBLISHED: 09-01-2014
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The purpose of this study was to investigate the association between chronic lymphocytic thyroiditis (CLT) and malignant tumors of the thyroid.
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Phenotypic and functional characterization of cytokine-induced killer cells derived from preterm and term infant cord blood.
Oncol. Rep.
PUBLISHED: 09-01-2014
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Cord blood has gradually become an important source for hematopoietic stem cell transplantation (HSCT) in the human, particularly in pediatric patients. Adoptive cellular immunotherapy of patients with hematologic malignancies after umbilical cord blood transplant is crucial. Cytokine?induced killer (CIK) cells derived from cord blood are a new type of antitumor immune effector cells in tumor prevention and treatment and have increasingly attracted the attention of researchers. On the other hand, it has been suggested that preterm infant cord blood retains an early differentiation phenotype suitable for immunotherapy. Therefore, we determined the phenotypic and functional characterization of CIK cells derived from preterm infant cord blood (PCB-CIK) compared with CIK cells from term infant cord blood (TCB-CIK). Twenty cord blood samples were collected and classified into two groups based on gestational age. Cord blood mononuclear cells (CBMCs) were isolated, cultured and induced to CIK cells in vitro. We used flow cytometry to detect cell surface markers, FlowJo software to analyze the proliferation profile and intracellular staining to test the secretion of cytokines. Finally, we evaluated the antitumor activity of CIK cells against K562 in vitro. Compared with TCB-CIK, PCB-CIK cells demonstrated faster proliferation and higher expression of activated cell surface markers. The secretion of IL-10 was lower in PCB-CIK cells while the expression of perforin and CD107a had no significant difference between the two cell groups. PCB-CIK cells exhibited a high proliferation rate while the cytotoxic activity had no difference between the PCB-CIK and TCB-CIK cells. Hence preterm infant cord blood may be a potential source for immunotherapy.
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[Short-term curative effect of ribavirin combination therapy with pegylated interferon alfa-2a vs.interferon alfa-2a in patients with chronic hepatitis C].
Zhonghua Gan Zang Bing Za Zhi
PUBLISHED: 09-01-2014
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To perform a retrospective cohort study in order to determine the differences in short-term curative effect of ribavirin in combination with interferon alfa (IFNa)-2a vs.pegylated (Peg)-IFNa-2a in patients with chronic hepatitis C (CHC).
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Giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor.
Nat Mater
PUBLISHED: 08-31-2014
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Two-dimensional (2D) transition metal dichalcogenides (TMDs) are emerging as a new platform for exploring 2D semiconductor physics. Reduced screening in two dimensions results in markedly enhanced electron-electron interactions, which have been predicted to generate giant bandgap renormalization and excitonic effects. Here we present a rigorous experimental observation of extraordinarily large exciton binding energy in a 2D semiconducting TMD. We determine the single-particle electronic bandgap of single-layer MoSe2 by means of scanning tunnelling spectroscopy (STS), as well as the two-particle exciton transition energy using photoluminescence (PL) spectroscopy. These yield an exciton binding energy of 0.55 eV for monolayer MoSe2 on graphene-orders of magnitude larger than what is seen in conventional 3D semiconductors and significantly higher than what we see for MoSe2 monolayers in more highly screening environments. This finding is corroborated by our ab initio GW and Bethe-Salpeter equation calculations which include electron correlation effects. The renormalized bandgap and large exciton binding observed here will have a profound impact on electronic and optoelectronic device technologies based on single-layer semiconducting TMDs.
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Surgical treatment of bronchiectasis: A retrospective observational study of 260 patients.
Int J Surg
PUBLISHED: 08-30-2014
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This study aims to demonstrate our surgical experience for bronchiectasis and analyze the risk factors related with the surgery outcome.
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Channelrhodopsin-2-expressed dorsal root ganglion neurons activates calcium channel currents and increases action potential in spinal cord.
Spine
PUBLISHED: 08-30-2014
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We used optogenetic techniques in spinal cord and dorsal root ganglion (DRG) neuron studies.
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Minimizing lipid signal bleed in brain (1) H chemical shift imaging by post-acquisition grid shifting.
Magn Reson Med
PUBLISHED: 08-28-2014
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Low spatial resolution in conventional (1) H brain chemical shifting imaging (CSI) studies causes partial volume error (PVE) or signal "bleed" that is especially deleterious to voxels near the scalp. The standard spatial apodization approach adversely affects spatial resolution. Here, a novel automated post-processing strategy of partial volume correction employing grid shifting ("PANGS") is presented, which minimizes residual PVE without compromising spatial resolution.
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Decoding the role of chromatin architecture in development: coming closer to the end of the tunnel.
Front Plant Sci
PUBLISHED: 08-21-2014
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Form and function in biology are intimately related aspects that are often difficult to untangle. While the structural aspects of chromatin organization were apparent from early cytological observations long before the molecular details of chromatin functions were deciphered, the extent to which genome architecture may impact its output remains unclear. A major roadblock to resolve this issue is the divergent scales, both temporal and spatial, of the experimental approaches for examining these facets of chromatin biology. Recent advances in high-throughput sequencing and informatics to model and monitor genome-wide chromatin contact sites provide the much-needed platform to close this gap. This mini-review will focus on discussing recent efforts applying new technologies to elucidate the roles of genome architecture in coordinating global gene expression output. Our discussion will emphasize the potential roles of differential genome 3-D structure as a driver for cell fate specification of multicellular organisms. An integrated approach that combines multiple new methodologies may finally have the necessary temporal and spatial resolution to provide clarity on the roles of chromatin architecture during development.
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Children's mental time travel during mind wandering.
Front Psychol
PUBLISHED: 08-21-2014
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The prospective bias is a salient feature of mind wandering in healthy adults, yet little is known about the temporal focus of children's mind wandering. In the present study, (I) we developed the temporal focus of mind wandering questionnaire for school-age children (TFMWQ-C), a 12-item scale with good test-retest reliability and construct validity. (II) The criterion validity was tested by thought sampling in both choice reaction time task and working memory task. A positive correlation was found between the temporal focus measured by the questionnaire and the one adopted during task-unrelated thoughts (TUTs) by thought sampling probes, especially in the trait level of future-oriented mind wandering. At the same time, children who experienced more TUTs tended to show worse behavioral performance during tasks. (III) The children in both tasks experienced more future-oriented TUTs than past-oriented ones, which was congruent with the results observed in adults; however, in contrast with previous research on adults, the prospective bias was not influenced by task demands. Together these results indicate that the prospective bias of mind wandering has emerged since the school-age (9?13 years old), and that the relationship between mental time travel (MTT) during mind wandering and the use of cognitive resources differs between children and adults. Our study provides new insights into how this interesting feature of mind wandering may adaptively contribute to the development of children's MTT.
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Epigenetic regulation of CD271, a potential cancer stem cell marker associated with chemoresistance and metastatic capacity.
Oncol. Rep.
PUBLISHED: 08-19-2014
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Cancer stem cells (CSCs) are considered to be the cause of tumor initiation, metastasis and recurrence. Additionally, CSCs are responsible for the failure of chemotherapy and radiotherapy. The isolation and identification of CSCs is crucial for facilitating the monitoring, therapy or prevention of cancer. We aimed to identify esophageal squamous cell carcinoma (ESCC) stem-like cells, the epigenetic mechanism and identify novel biomarkers for targeting ESCC CSCs. Sixty-three paired ESCC tissues and adjacent non-cancerous tissues were included in this study. CD271, which was identified as the CSC marker for melanoma, was assessed using quantitative PCR (qPCR). Using flow cytometry, we isolated CD271+ cells comprising 7.5% of cancer cells from the KYSE70 cell line. Sphere formation and anchorage-independent growth were analyzed in CD271+ and CD271- cancer cells, respectively. qPCR was used to detect stem-related genes and CCK-8 was performed to analyze the sensitivity to chemotherapy in the two groups. Bisul?te genomic sequencing was used to analyze the methylation status. CD271 expression was significantly higher in ESCC tissues than in adjacent non-cancerous tissues. Compared with CD271- cancer cells, CD271+ cancer cells showed a higher ability of sphere and colony formation, a high level expression of stem-related gene, and resistance to chemotherapy. The expression of CD271 was induced by a demethylation agent. In conclusion, CD271+ ESCC cells possess stem-like properties. CD271 can potentially act as a prognostic marker for ESCC, whose expression is regulated epigenetically.
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An integrative review of ethnic and cultural variation in socialization and children's self-regulation.
J Adv Nurs
PUBLISHED: 08-16-2014
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To examine the evidence for cross-cultural variation in socialization and children's normative self-regulation, based on a contextual-developmental perspective.
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Genetic variant in NDUFS1 gene is associated with schizophrenia and negative symptoms in Han Chinese.
J. Hum. Genet.
PUBLISHED: 08-15-2014
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Abnormalities in mitochondrial complex I, which is responsible for controlling mitochondrial function, have been implicated in a variety of diseases associated with mitochondrial dysfunction, potentially including schizophrenia. The NADH dehydrogenase Fe-S protein 1 (NDUFS1) is the largest subunit of complex I. To explore whether the encoding NDUFS1 gene confers susceptibility to schizophrenia or is associated with the severity of typical symptoms of schizophrenia, we recruited 519 stable schizophrenia patients receiving clozapine treatment and 594 healthy controls for genotyping to investigate the association of four selected tagging single-nucleotide polymorphisms (SNPs) of NDUFS1 and both schizophrenia risk and symptom severity. The severity of psychotic symptoms was evaluated using the Positive and Negative Syndrome Scale and then tested for association with the four SNPs. The SNP rs1044120 showed significant association with schizophrenia (adjusted P=0.032). The frequency of the G allele of rs1044120 was significantly higher in patients than among the healthy controls (adjusted P=0.008). Stratification by sex revealed a significant association between the rs1044120 polymorphism and schizophrenia among males (adjusted P=0.036 and 0.008 in genotypic and allelic comparisons, respectively). We also observed a significant difference in the negative symptom scores among the three genotypes among these males (adjusted P=0.036). Post hoc comparisons showed that rs1044120 G/G carriers had higher negative symptom scores than those with G/T and T/T carriers (raw P=0.035 and 0.005, respectively). Our findings suggest that NDUFS1 may confer susceptibility to schizophrenia in male subjects, acting as a causative factor for the severity of negative symptoms in schizophrenia.Journal of Human Genetics advance online publication, 30 October 2014; doi:10.1038/jhg.2014.94.
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Mechanisms for U2AF to define 3' splice sites and regulate alternative splicing in the human genome.
Nat. Struct. Mol. Biol.
PUBLISHED: 08-14-2014
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The U2AF heterodimer has been well studied for its role in defining functional 3' splice sites in pre-mRNA splicing, but many fundamental questions still remain unaddressed regarding the function of U2AF in mammalian genomes. Through genome-wide analysis of U2AF-RNA interactions, we report that U2AF has the capacity to directly define ~88% of functional 3' splice sites in the human genome, but numerous U2AF binding events also occur in intronic locations. Mechanistic dissection reveals that upstream intronic binding events interfere with the immediate downstream 3' splice site associated either with the alternative exon, to cause exon skipping, or with the competing constitutive exon, to induce exon inclusion. We further demonstrate partial functional impairment with leukemia-associated mutations in U2AF35, but not U2AF65, in regulated splicing. These findings reveal the genomic function and regulatory mechanism of U2AF in both normal and disease states.
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Combination of SNX-2112 with 5-FU exhibits antagonistic effect in esophageal cancer cells.
Int. J. Oncol.
PUBLISHED: 08-13-2014
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The low efficacy of single-drug chemotherapy forms the basis for combination therapy in esophageal squamous cell carcinoma. SNX-2112, a selective heat shock protein 90 (Hsp90) inhibitor, was recently reported as being effective in combination with cisplatin and paclitaxel. In this study, we investigated the effect of SNX-2112 in combination with 5-fluorouracil (5-FU), another first-line anticancer drug, in esophageal cancer. Unexpectedly, tetrazolium assay revealed that the combination of SNX-2112 with 5-FU exhibited antagonistic effect. Flow cytometry revealed that the SNX-2112 and 5-FU combination greatly decreased the number of G2/M cells compared to SNX-2112-only treatment in Eca?109 cells. This effect might be related to the altered mRNA level of cyclin-related genes including cyclin D1, Chk2 and Cdk4. Further, 5-FU attenuated SNX-2112-induced apoptosis by decreasing poly(ADP-ribose) polymerase (PARP) cleavage and inactivating caspase-3, -8 and -9. Additionally, 5-FU suppressed the SNX-2112-induced decrease of mitochondrial membrane potential. Moreover, 5-FU partly recovered Hsp90 client proteins, including Akt, p-Akt, inhibitor of ?B kinase (IKK)?, extracellular signal-regulated kinase (ERK)1/2, and glycogen synthase kinase (GSK)-3?, which SNX-2112 had downregulated. Taken together, this is the first report that the combination of SNX-2112 with 5-FU exhibited antagonistic effect in esophageal cancer cells by affecting growth inhibition, cell cycle, apoptosis, and Hsp90 client proteins, suggesting that care is required in the clinical application of combined SNX-2112 and 5-FU.
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Tet3 and DNA replication mediate demethylation of both the maternal and paternal genomes in mouse zygotes.
Cell Stem Cell
PUBLISHED: 08-11-2014
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With the exception of imprinted genes and certain repeats, DNA methylation is globally erased during preimplantation development. Recent studies have suggested that Tet3-mediated oxidation of 5-methylcytosine (5mC) and DNA replication-dependent dilution both contribute to global paternal DNA demethylation, but demethylation of the maternal genome occurs via replication. Here we present genome-scale DNA methylation maps for both the paternal and maternal genomes of Tet3-depleted and/or DNA replication-inhibited zygotes. In both genomes, we found that inhibition of DNA replication blocks DNA demethylation independently from Tet3 function and that Tet3 facilitates DNA demethylation largely by coupling with DNA replication. For both genomes, our data indicate that replication-dependent dilution is the major contributor to demethylation, but Tet3 plays an important role, particularly at certain loci. Our study thus defines the respective functions of Tet3 and DNA replication in paternal DNA demethylation and reveals an unexpected contribution of Tet3 to demethylation of the maternal genome.
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Supraomohyoid neck dissection and modified radical neck dissection for clinically node-negative oral squamous cell carcinoma: A prospective study of prognosis, complications and quality of life.
J Craniomaxillofac Surg
PUBLISHED: 08-06-2014
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To assess the prognosis and morbidity between supraomohyoid neck dissection (SOND) and modified radical neck dissection (MRND) for oral squamous cell carcinoma (OSCC) in patients with a clinically node-negative neck (cN0).
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RNA interference-mediated knockdown of RhoGDI2 induces the migration and invasion of human lung cancer A549 cells via activating the PI3K/Akt pathway.
Tumour Biol.
PUBLISHED: 08-04-2014
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Rho GDP dissociation inhibitor 2 (RhoGDI2) has been identified as a tumor suppressor gene for cellular migration and invasion. However, the underlying mechanism and effector targets of RhoGDI2 in lung cancer are still not fully understood. In this study, a vector-expressed small hairpin RNA (shRNA) of RhoGDI2 was transfected into the human lung cancer cell line A549. After the successful transfection, the down-regulation of RhoGDI2 promoted the proliferation, migration, and invasion of lung cancer cells in vitro through the increasing expression and activities of the matrix metallopeptidase 9 (MMP-9) and PI3K/Akt pathways. Transiently transfecting the small interfering RNA (siRNA) of MMP-9 into the RhoGDI2 shRNA cells reduced the MMP-9 expression. Both transfecting the siRNA and adding the MMP-9 antibody into the RhoGDI2 shRNA cells led to a decrease in the invasion and migration of the lung cancer cells. The blockade of the PI3K/Akt pathway by LY294002 resulted in abolishment of the effects of RhoGDI2 shRNA in Akt phosphorylation and MMP-9 expression. This result suggests that the down-regulated RhoGDI2 contributed to the migration and invasion of the lung cancer cell line via activating the PI3K/Akt pathway and the ensuing increase in the expression and activity of MMP-9. In conclusion, we report that the shRNA-mediated knockdown of RhoGDI2 induces the invasion and migration of lung cancer due to cross-talk with the PI3K/Akt pathway and MMP-9. Verifying the role and molecular mechanism of the participation of RhoGDI2 in the migration and invasion of lung cancer may provide a target for better treatment.
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An equivalent circuit model for onset and offset exercise response.
Biomed Eng Online
PUBLISHED: 08-01-2014
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The switching exercise (e.g., Interval Training) has been a commonly used exercise protocol nowadays for the enhancement of exerciser's cardiovascular fitness. The current difficulty for simulating human onset and offset exercise responses regarding the switching exercise is to ensure the continuity of the outputs during onset-offset switching, as well as to accommodate the exercise intensities at both onset and offset of exercise.
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Wogonin Reverses Multi-Drug Resistance of Human myelogenous leukemia K562/A02 cells via Downregulation of MRP1 Expression by Inhibiting Nrf2/ARE Signaling Pathway.
Biochem. Pharmacol.
PUBLISHED: 07-28-2014
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Constitutive NF-E2-related factor 2(Nrf2) activation has been recently reported to play a pivotal role in enhancing cell survival and resistance to anticancer drugs in many tumors. Previously, much effort has been devoted to the investigation of blocking Nrf2 function in cultured cells and cancer tissues, but few research has been undertaken to evaluate the precise mechanism of flavonoids-induced sensitivity by inhibiting Nrf2. In this study, we investaged the reversal effect of Wogonin, a flavonoid isolated from the root of Scutellaria baicalensis Georgi, in resistant human myelogenous leukemia. Data indicated that Wogonin had strong reversal potency by inhibiting functional activity and expression of MRP1 at both protein and mRNA in adriamycin(ADR)-induced resistant human myelogenous leukemia K562/A02 cells. Consequently, the inhibition of MRP1 by Wogonin was dependent on Nrf2 through the decreased binding ability of Nrf2 to antioxidant response element(ARE). Further research revealed Wogonin modulated Nrf2 through the reduction of Nrf2mRNA at transcriptional processes rather than RNA degradation, which is regulated by the PI3K/Akt pathway. Moreover, DNA-PKcs was found to be involved in the Wogonin-induced downregulation of Nrf2 mRNA at transcriptional levels. In summary, these results clearly demonstrated the effectiveness of using Wogonin via inhibiting Nrf2 to combat chemoresistance and suggested that Wogonin can be developed into an efficient natural sensitizer for resistant human myelogenous leukemia.
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New terpenoid glycosides obtained from Rosmarinus officinalis L. aerial parts.
Fitoterapia
PUBLISHED: 07-26-2014
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Five new terpenoid glycosides, named as officinoterpenosides A1 (1), A2 (2), B (3), C (4), and D (5), together with 11 known ones, (1S,4S,5S)-5-exo-hydrocamphor 5-O-?-d-glucopyranoside (6), isorosmanol (7), rosmanol (8), 7-methoxyrosmanol (9), epirosmanol (10), ursolic acid (11), micromeric acid (12), oleanolic acid (13), niga-ichigoside F1 (14), glucosyl tormentate (15), and asteryunnanoside B (16), were obtained from the aerial parts of Rosmarinus officinalis L. Their structures were elucidated by chemical and spectroscopic methods (UV, IR, HRESI-TOF-MS, 1D and 2D NMR). Among the new ones, 1 and 2, 3 and 4 are diterpenoid and triterpenoid glycosides, respectively; and 5 is a normonoterpenoid. For the known ones, 6 was isolated from the Rosmarinus genus first, and 15, 16 were obtained from this species for the first time.
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Waltonitone induces apoptosis through mir-663-induced Bcl-2 downregulation in non-small cell lung cancer.
Tumour Biol.
PUBLISHED: 07-24-2014
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Our previous study reported that waltonitone treatment inhibited proliferation and induced apoptosis of lung cancer cells. However, the mechanism of waltonitone-induced toxicity remains unclear. In the present study, we treated H460 and H3255 lung cancer cells using different concentration of waltonitone (0, 10, 20, 30 ?mol/L). We observed that waltonitone inhibited cell viability and induced apoptosis in a concentration dependent manner, with upregulation of caspase-3 cleavage. We also observed upregulation of miR-663, a potential tumor suppressor, after waltonitone treatment. Suppression of miR-663 function using miR-663 inhibitor partly alleviated cell toxicity induced by waltonitone. In addition, both waltonitone treatment and transfection of miR-663 mimic upregulated Bcl-2 mRNA and protein expression. Bcl-2 transfection alleviated waltonitone-induced toxicity. Furthermore, transfection of miR-663 inhibitor upregulated Bcl-2 levels in both cell lines. In summary, the present study demonstrated that waltonitone induced apoptosis of lung cancer cells through, at least partly, miR-663-induced Bcl-2 downregulation.
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A Review of Recent Research Progress on the Astragalus Genus.
Molecules
PUBLISHED: 07-22-2014
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Astragalus L., is one of the largest genuses of flowering plants in the Leguminosae family. Roots of A. membranaceus Bge. var. mongholicus (Bge.) Hsiao, A. membranaceus (Fisch.) Bge. and its processed products are listed in the China Pharmacopeia for "qi deficiency" syndrome treatment. However, more and more researches on other species of Astragalus have been conducted recently. We summarize the recent researches of Astragalus species in phytochemistry and pharmacology. More than 200 constituents, including saponins and flavonoids, obtained from 46 species of Astragalus genus were collected for this article. In pharmacological studies, crude extracts of Astragalus, as well as isolated constituents showed anti-inflammatory, immunostimulant, antioxidative, anti-cancer, antidiabetic, cardioprotective, hepatoprotective, and antiviral activities. The goal of this article is to provide an overview of chemical and pharmacological studies on the Astragalus species over the last 10 years, which could be of value to new drug or food supplement research and development.
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Cucurbitacin B inhibits proliferation and induces apoptosis via STAT3 pathway inhibition in A549 lung cancer cells.
Mol Med Rep
PUBLISHED: 07-21-2014
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Natural products are a great source of cancer chemotherapeutic agents. The present study was conducted to investigate whether cucurbitacin B (CuB), one of the most potent and widely used cucurbitacins, inhibits proliferation and induces apoptosis in the A549 lung cancer cell line. Furthermore, CuB induced apoptosis of A549 cells in a -concentration-dependent manner, as determined by fluorescence microscopy, flow cytometry and transmission electron microscopy. The present study also demonstrated that CuB dose-dependently inhibited lung cancer cell proliferation, with cell cycle inhibition and cyclin B1 downregulation. Apoptosis induced by CuB was shown to be associated with cytochrome c release, B-cell lymphoma 2 downregulation and signal transducer and activator of transcription 3 pathway inhibition. CuB may prove to be a useful approach for the chemotherapy of lung cancer.
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Heptamethine carbocyanine dye-mediated near-infrared imaging of canine and human cancers through the HIF-1?/OATPs signaling axis.
Oncotarget
PUBLISHED: 07-13-2014
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Near-infrared (NIR) fluorescence imaging agents are promising tools for noninvasive cancer imaging. This study explored the specific uptake and retention of a NIR heptamethine carbocyanine MHI-148 dye by canine cancer cells and tissues and human prostate cancer (PCa) specimens and also the dye uptake mechanisms. The accumulation of MHI-148 was detected specifically in canine cancer cells and tissues and freshly harvested human PCa tissues xenografted in mice by NIR fluorescence microscopy and whole-body NIR optical imaging. Specific dye uptake in canine spontaneous tumors was further confirmed by PET imaging. Higher hypoxia-inducible factor-1? (HIF-1?) and organic anion-transporting polypeptide (OATP) protein and mRNA expression was demonstrated by multiplex quantum dots labeling and qPCR in tumors over that of normal tissues. Treating cancer cells with HIF-1? stabilizers activated HIF-1? downstream target genes, induced OATP superfamily gene expression and enhanced cellular uptake and retention of NIR dyes. Moreover, silencing HIF-1? by siRNA significantly decreased OATP mRNA expression and blocked NIR dye uptake in cancer cells. Together, these results demonstrated the preferential uptake of NIR dyes by canine and human cancer cells and tissues via the HIF-1?/OATPs signaling axis, which provides insights into future application of these dyes for cancer detection and treatment.
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Central hemodynamics in risk assessment strategies: Additive value over and above brachial blood pressure.
Curr. Pharm. Des.
PUBLISHED: 07-09-2014
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Although the clinical relevance of brachial blood pressure (BP) measurement for cardiovascular (CV) risk stratification is nowadays widely accepted, this approach can nevertheless present several limitations. Pulse pressure (PP) amplification accounts for the notable increase in PP from central to peripheral arterial sites. Target organs are more greatly exposed to central hemodynamic changes than peripheral organs. The pathophysiological significance of local BP pulsatility, which has a role in the pathogenesis of target organ damage in both the macro- and the microcirculation, may therefore not be accurately captured by brachial BP as traditionally evaluated with cuff measurements. The predictive value of central systolic BP and PP over brachial BP for major clinical outcomes has been demonstrated in the general population, in elderly adults and in patients at high CV risk, irrespective of the invasive or non-invasive methods used to assess central BP. Aortic stiffness, timing and intensity of wave reflections, and cardiac performance appear as major factors influencing central PP. Great emphasis has been placed on the role of aortic stiffness, disturbed arterial wave reflections and their intercorrelation in the pathophysiological mechanisms of CV diseases as well as on their capacity to predict target organ damage and clinical events. Comorbidities and age-related changes, together with gender-related specificities of arterial and cardiac parameters, are known to affect the predictive ability of central hemodynamics on individual CV risk.
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An Above-Room-Temperature Ferroelectric Organo-Metal Halide Perovskite: (3-Pyrrolinium)(CdCl3 ).
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 07-02-2014
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Hybrid organo-metal halide perovskite materials, such as CH3 NH3 PbI3 , have been shown to be some of the most competitive candidates for absorber materials in photovoltaic (PV) applications. However, their potential has not been completely developed, because a photovoltaic effect with an anomalously large voltage can be achieved only in a ferroelectric phase, while these materials are probably ferroelectric only at temperatures below 180?K. A new hexagonal stacking perovskite-type complex (3-pyrrolinium)(CdCl3 ) exhibits above-room-temperature ferroelectricity with a Curie temperature Tc =316?K and a spontaneous polarization Ps =5.1??C?cm(-2) . The material also exhibits antiparallel 180°?domains which are related to the anomalous photovoltaic effect. The open-circuit photovoltage for a 1?mm-thick bulky crystal reaches 32?V. This finding could provide a new approach to develop solar cells based on organo-metal halide perovskites in photovoltaic research.
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Bio-electrospraying is a safe technology for delivering human adipose-derived stem cells.
Biotechnol. Lett.
PUBLISHED: 06-29-2014
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Bio-electrospraying (BES) is a technique for directly jetting living cells that has significant implications for tissue engineering and regenerative medicine. However, the effect of BES on human adipose-derived stem cells (hASCs) remains unknown. Here, we show that an hASC suspension was successfully electrosprayed via a continuous, stable and linearly directed electrospray at 10 kV and at 3 ml/h. Morphological observations and Trypan Blue and CCK-8 assays revealed that the cells remained viable and proliferated at a rate similar to that of the controls (0 kV). However, at 20 kV, BES became unstable and cell viability was reduced. Moreover, hASCs electrosprayed at 10 kV retained their multilineage potential, successfully differentiating into chondrogenic, osteogenic and neurogenic lineages. Thus, BES does not significantly affect cell morphology, viability or multipotency.
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Sensitive analysis of amino acids and vitamin B3 in functional drinks via field-amplified stacking with reversed-field stacking in microchip electrophoresis.
Talanta
PUBLISHED: 06-27-2014
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An on-line preconcentration strategy combining field-amplified stacking and reversed-field stacking was developed for efficient and sensitive analysis of amino acids and vitamin B3 including lysine (Lys), taurine (Tau), and niacinamide (NA) by microchip electrophoresis with LIF detection. In this technique, the addition of a reversed-polarity step termed reversed-field stacking could enhance the preconcentration effect of field-amplified stacking and push most of the sample matrix out of the separation channel, thus greatly improving the sensitivity enhancement by 1-2 orders of magnitude over the classical MCE-LIF methods. The related mechanism as well as important parameters governing preconcentration and separation have been investigated in order to obtain strongest sensitivity amplification and maximum resolution. Under optimal conditions, all analytes were successfully focused and completely separated within 4 min. The limits of detection for Lys, Tau, and NA were 0.25, 0.50, and 0.20 nM (S/N=3), respectively, and enhancement factors of 165-, 285-, and 236-fold were obtained for Lys, Tau, and NA as compared to using the no concentration step. Other validation parameters such as linearity and precision were considered as satisfactory. The proposed method also gave accurate and reliable results in the analysis of these functional ingredients in eight functional drink samples.
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