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Find video protocols related to scientific articles indexed in Pubmed.
Screening and Identification of Multi-Components in Re Du Ning Injections Using LC/TOF-MS Coupled with UV-Irradiation.
J Chromatogr Sci
PUBLISHED: 10-01-2014
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A high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry-UV-irradiation (HPLC-QTOF-MS-UV) method was established for rapid separation and structural identification of the constituents in Re Du Ning Injections (RDNI). A total of 20 potentially bioactive compounds including 10 caffeoylquinic acids and 10 iridoid glycosides were identified or tentatively characterized in RDNI by comparing their retention times and MS spectra with those of authentic standards or literature data. In particular, UV-irradiation was employed in the identification of the cis/trans isomers of caffeoylquinic acids. Furthermore, each compound was assigned to the individual raw materials (Artemisia annua L., Lonicera japonica Thunb. or Gardenia jasminoides Ellis) present in RDNI. This is the first time that an HPLC-QTOF-MS-UV analytical method has been used for the identification of caffeoylquinic acids in RDNI.
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Leptomeningeal metastases from a primary central nervous system melanoma: a case report and literature review.
World J Surg Oncol
PUBLISHED: 08-20-2014
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Primary central nervous system (CNS) melanoma is a type of rare and aggressive tumor that can easily spread to the leptomeninges, and in fact, leptomeningeal metastasis is one of the most serious complications in patients with this carcinoma. Prognosis is extremely poor if a CNS melanoma has metastasized, and there are no effective treatments. Here, we present a case of a 37-year-old woman who presented with horizontal diplopia and progressive headache. Magnetic resonance imaging findings were consistent with the diagnosis of melanoma. The results of cytological examination of cerebrospinal fluid (CSF) showed malignant cells characteristic of melanoma. No extracranial lesions were observed. All of the available evidence confirmed a diagnosis of leptomeningeal metastases from a primary CNS melanoma. The patient received aggressive treatment, which consisted of concurrent radiotherapy and weekly intra-CSF methotrexate (MTX) followed by adjuvant monthly intra-CSF MTX. Her survival time was 13 months after diagnosis. This case report suggests that the modality of concurrent radiotherapy and weekly intra-CSF MTX followed by adjuvant monthly intra-CSF MTX may be used as the mainstay of treatment for such patients.
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Leptomeningeal metastasis from hepatocellular carcinoma with other unusual metastases: a case report.
BMC Cancer
PUBLISHED: 01-26-2014
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Leptomeningeal metastasis, which results from metastasis of tumors to the arachnoid and pia mater, can lead to the dissemination of tumor cells throughout the subarachnoid space via the cerebral spinal fluid, and frequently with a poor prognosis. The primary tumor in adults is most often breast cancer, lung cancer, or melanoma. Although leptomeningeal metastasis due to cholangiocarcinoma has been reported, to the best of our knowledge there is no cytologically confirmed report of leptomeningeal metastasis from hepatocellular carcinoma.
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FoxO3a contributes to the reprogramming process and the differentiation of induced pluripotent stem cells.
Stem Cells Dev.
PUBLISHED: 08-09-2013
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Induced pluripotent stem (iPS) cells, which are morphologically and functionally similar with embryonic stem (ES) cells, have been successfully generated from somatic cells through defined reprogramming transcription factors. Forkhead class O3a (FoxO3a) has been recently reported to play an important role in the homeostasis and maintenance of certain types of stem cells; however, the role of FoxO3a in the reprogramming process and differentiation of iPS cells remains unclear. In this study, we investigate the function of FoxO3a during the reprogramming process and characterize the properties of iPS cells from FoxO3a-wild type and -null mouse embryonic fibroblasts (MEFs). Our results show that the FoxO3a-null iPS cells are similar to the wild-type iPS cells in the levels of ES cell markers, alkaline phosphatase activity, and formation of teratoma in vivo. The reprogramming process is delayed in the FoxO3a-null MEFs compared to the wild-type MEFs; whereas the overexpression of FoxO3a partially recovers the impaired reprogramming efficiency in the null group. More importantly, FoxO3a deficiency impairs the neuronal lineage differentiation potential of iPS cells in vitro. These results suggest that FoxO3a affects the reprogramming kinetics and the neuronal lineage differentiation potential of the resulting iPS cells. Therefore, this study demonstrates a novel function of FoxO3a in cell reprogramming, which will help the development of alternative strategies for generating iPS cells.
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Apoptosis of Human Pancreatic Carcinoma PC-2 Cells by an Antisense Oligonucleotide Specific to Point Mutated K-ras.
Pathol. Oncol. Res.
PUBLISHED: 06-03-2013
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The prognosis of pancreatic carcinoma is poor due to the difficulty in early diagnosis, insensitivity to routine therapies and limited understanding of its pathological mechanisms. Gene therapy is now becoming an important strategy for the treatment of pancreatic carcinoma, which includes antisense gene therapy. In this study, we investigated the effect of an antisense oligonucleotide specific to point mutated K-ras on the apoptosis of human pancreatic carcinoma cells in vitro. Human pancreatic carcinoma PC-2 cells were transfected with an antisense oligonucleotide specific to a K-ras point mutation by liposomes. The effect of the antisense oligonucleotide on the apoptosis of PC-2 cells was studied using flow cytometry, TUNEL, and phase contrast microscopy. An apoptotic peak was observed in the experimental group, and most cells were arrested at the G1 phase with few cells at the S phase. The numbers of apoptotic cells in the experimental group increased as indicated by TUNEL and phase contrast microscopy. An antisense oligonucleotide specific to a K-ras point mutation promotes apoptosis in PC-2 cells in vitro perhaps by inhibition of ras gene expression.
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Effects of Nogo-A receptor antagonist on the regulation of the Wnt signaling pathway and neural cell proliferation in newborn rats with hypoxic ischemic encephalopathy.
Mol Med Rep
PUBLISHED: 02-16-2013
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Hypoxic ischemic encephalopathy is a serious condition due to inadequate oxygen supply to the brain. Regeneration of neural cells is a critical process for repairing the damaged brain. Nogo has been identified as an inhibitor of neurite outgrowth that is specific to the brain. In the present study, the Nogo-A receptor (NgR) antagonist NEP1-40 was used to study the effects of inhibition of NgR on the regeneration of neural cells and the related Wnt signaling pathway in newborn rats. The investigation focused on the transcription factors regulated in the Wnt signaling pathway during the repair process, together with the proliferation of neural cells. The results indicated that c-Jun and c-Myc were the main transcription factors involved in the Wnt signaling pathway, while neural cell proliferation in the subventricular zone was increased during this process.
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Characterization of induced neural progenitors from skin fibroblasts by a novel combination of defined factors.
Sci Rep
PUBLISHED: 02-12-2013
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Recent reports have demonstrated that somatic cells can be directly converted to other differentiated cell types through ectopic expression of sets of transcription factors, directly avoiding the transition through a pluripotent state. Our previous experiments generated induced neural progenitor-like cells (iNPCs) by a novel combination of five transcription factors (Sox2, Brn2, TLX, Bmi1 and c-Myc). Here we demonstrated that the iNPCs not only possess NPC-specific marker genes, but also have qualities of primary brain-derived NPCs (WT-NPCs), including tripotent differentiation potential, mature neuron differentiation capability and synapse formation. Importantly, the mature neurons derived from iNPCs exhibit significant physiological properties, such as potassium channel activity and generation of action potential-like spikes. These results suggest that directly reprogrammed iNPCs closely resemble WT-NPCs, which may suggest an alternative strategy to overcome the restricted proliferative and lineage potential of induced neurons (iNCs) and broaden applications of cell therapy in the treatment of neurodegenerative disorders.
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Design of a dual-signaling sensing system for fluorescent ratiometric detection of Al3+ ion based on the inner-filter effect.
Analyst
PUBLISHED: 09-30-2011
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A dual-signal sensing system based on the inner-filter effect (IFE) was demonstrated, in which the combination of two signaling mechanisms allows metal binding to turn on two fluorescence emission bands, independently. A proof-of-concept fluorescent ratiometric assay for Al(3+) in pure aqueous solution is presented. The proposed assay is based on the Al(3+)-induced color and fluorescence changes of Alizarin red S (ARS) and IFE between ARS and meso-tetra(N-methyl-4-pyridyl)porphine tetratosylate salt (TMPyP). In the absence of Al(3+), the absorption spectrum of the ARS in 0.2 M HAc-NaAc buffer (pH 5.5) has a strong peak at 420 nm, significantly overlapping with the excitation of TMPyP. ARS is expected to be capable of functioning as a powerful absorber to tune the emission of TMPyP on account of the spectral overlap. Binding of Al(3+) with ARS forms a fluorometric ARS/Al(3+) complex and shifts the maximum absorbance from 420 nm to 480 nm, which overlaps negligibly with the excitation of TMPyP and turns on the proper emission spectrum for TMPyP. Under the optimum conditions, The fluorescence intensity ratio, F(585)/F(651), responds to Al(3+) over a dynamic range of 0.1-1.5 ?M, with a limit of detection of 40 nM, where F(585) and F(651) are the fluorescence intensity at 585 nm and 651 nm in the absence or presence of Al(3+), respectively. Further application in Al(3+)-spiked water samples suggested a recovery between 95 and 108%. The fluorescence response is highly selective for Al(3+) over other metal ions with the addition of thiourea as the masking agent.
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Oligonucleotide-based label-free Hg2+ assay with a monomer-excimer fluorescence switch.
Analyst
PUBLISHED: 08-31-2011
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A novel fluorescent Hg(2+) sensor was developed based on the T-Hg(2+)-T structure and a thioflavine T monomer-excimer fluorescent switch. Under optimum conditions, the selectivity is remarkably high, and Hg(2+) can be quantified over the dynamic range of 0.1 to 1.2 ?M, with a limit of detection (LOD) of ~20 nM and a linear correlation coefficient of 0.995.
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Nucleic acid-modulated silver nanoparticles: a new electrochemical platform for sensing chloride ion.
Analyst
PUBLISHED: 07-26-2011
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Inorganic nanomaterials have generated considerable interest in connection to the design of biosensors. Here we exploit the DNA-induced generation of silver nanoparticles for developing an electrical biosensing protocol for chloride ions. Conjugated with thiol modified oligonucleotide, silver nanoparticles were template-synthesized and immobilized on gold electrode. During cyclic voltammogram (CV) scans, the silver nanoparticles were oxidized at high potential to form a layer of Ag/AgCl complex in the presence of Cl(-), giving off sharp solid state redox signals. Under the optimum condition, the electrode responded to Cl(-) over a dynamic range of 2.0 × 10(-5)-0.01 M, with a detection limit of 5.0 × 10(-6) M. Moreover, the specific solubility product constant-based anion recognition made the electrode applicable at a wide pH range and in complex biological systems. To demonstrate the analytical applications of this sensor in real samples, the Cl(-) concentrations in human urine were measured without any sample pretreatment. Urinary Cl(-) detected by the proposed sensor ranged from 110 to 200 mM, which was comparable to the results obtained by standard silver titration.
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[Study on best preparation procedure of Lumbricus for anticoagulated blood region in vitro].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 07-19-2011
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Applying for the activity of enzyme in vitro,the research optimized the best preparation procedure for the anticoagulated blood region from Lumbricus.
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[Depyrogenation in key manufacturing processes of Reduning injection].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 06-30-2011
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To investigate the effect of removing bacterial endotoxin in the key processes of Reduning injection.
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Generation of protective immune responses against coxsackievirus B3 challenge by DNA prime-protein boost vaccination.
Vaccine
PUBLISHED: 01-22-2011
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Coxsackievirus B3 (CVB3) causes viral myocarditis and can ultimately result in dilated cardiomyopathy. However, there is no vaccine available for clinical use. In this study, we assessed the protection provided by three immunization strategies against CVB3 infection. Vaccination was performed with a DNA vaccine expressing the cloned capsid gene VP1 or a vaccine developed from purified VP1 protein. Third, a strategy of vaccination was attempted with the DNA vaccine followed by two boosts with the recombinant protein vaccine (DNA prime-protein boost vaccine). Followed immunization, mice were challenged with CVB3 infection. Improved induction of CVB3-specific antibodies and neutralizing antibodies were found in mice immunized by the DNA prime-protein boost regimen. Furthermore, virus-specific cytotoxic activity of spleen cells derived from DNA prime-protein boost vaccinated mice was elicited. In addition, the DNA prime-protein boost vaccine resulted in protection of 75% of mice from lethal CVB3 challenge and a significant reduction of viral load in sera of immunized mice after acute CVB3 infection. There was a significant reduction in myonecrosis and infiltrating myocardial immune cells indicating reduced severity of myocarditis in surviving mice. These findings demonstrated that a DNA prime-protein boost immunization strategy, but not a DNA vaccine or protein vaccine alone, was effective in eliciting both humoral and cell-mediated immune responses against CVB3 infection in mice and might be a promising vaccine candidate.
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Reprogrammed mouse astrocytes retain a "memory" of tissue origin and possess more tendencies for neuronal differentiation than reprogrammed mouse embryonic fibroblasts.
Protein Cell
PUBLISHED: 01-15-2011
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Direct reprogramming of a variety of somatic cells with the transcription factors Oct4 (also called Pou5f1), Sox2 with either Klf4 and Myc or Lin28 and Nanog generates the induced pluripotent stem cells (iPSCs) with marker similarity to embryonic stem cells. However, the difference between iPSCs derived from different origins is unclear. In this study, we hypothesized that reprogrammed cells retain a "memory" of their origins and possess additional potential of related tissue differentiation. We reprogrammed primary mouse astrocytes via ectopic retroviral expression of OCT3/4, Sox2, Klf4 and Myc and found the iPSCs from mouse astrocytes expressed stem cell markers and formed teratomas in SCID mice containing derivatives of all three germ layers similar to mouse embryonic stem cells besides semblable morphologies. To test our hypothesis, we compared embryonic bodies (EBs) formation and neuronal differentiation between iPSCs from mouse embryonic fibroblasts (MEFsiPSCs) and iPSCs from mouse astrocytes (mAsiPSCs). We found that mAsiPSCs grew slower and possessed more potential for neuronal differentiation compared to MEFsiPSCs. Our results suggest that mAsiPSCs retain a "memory" of the central nervous system, which confers additional potential upon neuronal differentiation.
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The unique expression profile of human TIPE2 suggests new functions beyond its role in immune regulation.
Mol. Immunol.
PUBLISHED: 01-08-2011
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TIPE2 (tumor necrosis factor-?-induced protein 8-like 2, or TNFAIP8L2) is a newly identified negative regulator of innate and adaptive immunity. TIPE2 deficiency in mice leads to systemic inflammation and TIPE2 down-regulation in humans is associated with autoimmunity. However, the nature of human TIPE2-expressing cells in various tissues has not been characterized due to the lack of suitable antibodies. In the present study, we generated specific rabbit antibodies against human TIPE2 and examined human TIPE2 expression in various tissues by Western blot, flow cytometry, and immunohistochemistry. We found that unlike murine TIPE2 that is preferentially expressed by hematopoietic cells, human TIPE2 was also expressed in a wide variety of non-hematopoietic cell types, including hepatocytes, neurons in brain and brainstem, squamous epithelial cells in esophagus and cervix, transitional epithelial cells in bladder and ureter, and glandular epithelial cells in stomach, colon and appendix. For squamous epithelium, the level of TIPE2 expression increased dramatically in terminally differentiated cells with the proliferating precursor cells completely devoid of TIPE2. The unique expressional profile of human TIPE2 suggests new functions beyond controlling innate and adaptive immunity.
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[Compatible stability of reduning injection with solvents].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 09-27-2010
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To investigate the compatible stability of Reduning injection in different dosages with 5% glucose injection and 0.9% sodium chloride injection.
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Combination of DNA ligase reaction and gold nanoparticle-quenched fluorescent oligonucleotides: a simple and efficient approach for fluorescent assaying of single-nucleotide polymorphisms.
Anal. Chem.
PUBLISHED: 08-24-2010
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A new fluorescent sensing approach for detection of single-nucleotide polymorphisms (SNPs) is proposed based on the ligase reaction and gold nanoparticle (AuNPs)-quenched fluorescent oligonucleotides. The design exploits the strong fluorescence quenching of AuNPs for organic dyes and the difference in noncovalent interactions of the nanoparticles with single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA), where ssDNA can be adsorbed onto the surface of AuNPs while dsDNA cannot be. In the assay, two half primer DNA probes, one being labeled with a dye and the other being phosphorylated, were first incubated with a target DNA template. In the presence of DNA ligase, the two captured ssDNAs are linked for the perfectly matched DNA target to form a stable duplex, but the duplex could not be formed by the single-base mismatched DNA template. After addition of AuNPs, the fluorescence of dye-tagged DNA probe will be efficiently quenched unless the perfectly matched DNA target is present. To demonstrate the feasibility of this design, the performance of SNP detection using two different DNA ligases, T4 DNA ligase and Escherichia coli DNA ligase, were investigated. In the case of T4 DNA ligase, the signal enhancement of the dye-tagged DNA for perfectly matched DNA target is 4.6-fold higher than that for the single-base mismatched DNA. While in the presence of E. coli DNA ligase, the value raises to be 30.2, suggesting excellent capability for SNP discrimination.
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Totally thoracoscopic surgical resection of cardiac myxoma in 12 patients.
Ann. Thorac. Surg.
PUBLISHED: 07-30-2010
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Myxomas are the most common type of primary cardiac tumors. We report our use of totally thoracoscopic surgery in resecting cardiac myxomas in 12 cases with 10 in the left atria and 2 in the right atria. Totally thoracoscopic surgical resection of myxoma was successfully performed in all cases through three minimal incisions, with the largest incision less than 3 cm. The cardiopulmonary bypass time was 96 to 126 minutes, and the aortic cross-clamp time was 46 to 63 minutes. Postoperative ventilation assistance was 3 to 11 hours. We show that the method is safe and achieves complete tumor resection.
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Totally thoracoscopic surgical correction of total anomalous pulmonary venous connection.
Ann. Thorac. Surg.
PUBLISHED: 07-09-2010
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We report a case of total anomalous pulmonary venous connection in a 6-year-old boy who was successfully treated by thoracoscopic surgery. We believe this is the first report of the use of totally thoracoscopic surgery for the correction of a total anomalous pulmonary venous connection.
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Silver ions-mediated conformational switch: facile design of structure-controllable nucleic acid probes.
Anal. Chem.
PUBLISHED: 07-06-2010
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Conformationally constraint nucleic acid probes were usually designed by forming an intramolecular duplex based on Watson-Crick hydrogen bonds. The disadvantages of these approaches are the inflexibility and instability in complex environment of the Watson-Crick-based duplex. We report that this hydrogen bonding pattern can be replaced by metal-ligation between specific metal ions and the natural bases. To demonstrate the feasibility of this principle, two linear oligonucleotides and silver ions were examined as models for DNA hybridization assay and adenosine triphosphate detection. The both nucleic acids contain target binding sequences in the middle and cytosine (C)-rich sequences at the lateral portions. The strong interaction between Ag(+) ions and cytosines forms stable C-Ag(+)-C structures, which promises the oligonucleotides to form conformationally constraint formations. In the presence of its target, interaction between the loop sequences and the target unfolds the C-Ag(+)-C structures, and the corresponding probes unfolding can be detected by a change in their fluorescence emission. We discuss the thermodynamic and kinetic opportunities that are provided by using Ag(+) ion complexes instead of traditional Watson-Crick-based duplex. In particular, the intrinsic feature of the metal-ligation motif facilitates the design of functional nucleic acids probes by independently varying the concentration of Ag(+) ions in the medium.
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Strategy for molecular beacon binding readout: separating molecular recognition element and signal reporter.
Anal. Chem.
PUBLISHED: 11-11-2009
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A new strategy for molecular beacon binding readout is proposed by using separation of the molecular recognition element and signal reporter. The signal transduction of the target binding event is based on displacing interaction between the target DNA and a competitor, the signal transducer. The target-free capture DNA is first interacted with the competitor, forming an assembled complex. In the presence of a target DNA that the affinity is stronger than that of the competitor, hybridization between capture DNA and the target disassembles the assembled complex and releases the free competitor to change the readout of the signal reporter. To demonstrate the feasibility of the design, a thymine-rich oligonucleotide was examined as a model system. Hg2+ was selected as the competitor, and mercaptoacetic acid-coated CdTe/ZnS quantum dots served as the fluorescent reporter. Selective binding of Hg2+ between the two thymine bases of the capture DNA forms a hairpin-structure. Hybridization between the capture DNA and target DNA destroys the hairpin-structure, releasing Hg2+ ions to quench the quantum dots fluorescence. Under the optimal conditions, fluorescence intensity of the quantum dots against the concentration of perfect cDNA was linear over the concentration range of 0.1-1.6 microM, with a limit of detection of 25 nM. This new assay method is simple in design, avoiding any oligonucleotide labeling. Furthermore, this strategy is generalizable since any target binding can in principle release the signal transducer and be detected with separated signal reporter.
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Reversible molecular switching of molecular beacon: controlling DNA hybridization kinetics and thermodynamics using mercury(ii) ions.
Chem. Commun. (Camb.)
PUBLISHED: 01-21-2009
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We report that the hydrogen-bonding pattern in a molecular beacon can be replaced by metal-dependent pairs of Hg(2+) and DNA thymine (T) bases. A molecular beacon based on T-Hg(2+)-T exhibits a lower background signal and higher thermostability than regular molecular beacons.
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Synthesis and biological evaluation of a novel series of 1,5-benzothiazepine derivatives as potential antimicrobial agents.
Eur J Med Chem
PUBLISHED: 01-16-2009
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Two series of novel 1,5-benzothiazepine derivatives (23 compounds) were efficiently synthesized and evaluated for antibacterial and antifungal activities. The results indicated that the compounds possessed a broad spectrum of activity against the tested microorganisms and showed higher activity against fungi than bacteria. Compound 2e exhibited the greatest antimicrobial activity. Preliminary study of the structure-activity relationship revealed that substituents in phenyl rings had a great effect on the antimicrobial activity of these compounds.
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Fluorescent assay of DNA hybridization with label-free molecular switch: reducing background-signal and improving specificity by using carbon nanotubes.
Chem. Commun. (Camb.)
PUBLISHED: 01-07-2009
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Using classic DNA-intercalating dye and carbon nanotubes, a simple, but efficient, method for fluorescent detection of DNA hybridization has been developed.
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TNF-? affects human cortical neural progenitor cell differentiation through the autocrine secretion of leukemia inhibitory factor.
PLoS ONE
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Proinflammatory cytokine tumor necrosis factor-alpha (TNF-?) is a crucial effector of immune responses in the brain that participates in the pathogenesis of several acute and chronic neurodegenerative disorders. Accumulating evidence has suggested that TNF-? negatively regulates embryonic and adult neurogenesis. However, the effect of TNF-? on cell fate decision in human neural progenitor cells (NPCs) has rarely been studied. Our previous studies have shown that recombinant TNF-? enhances astrogliogenesis and inhibits neurogenesis of human NPCs through the STAT3 (signal transducer and activator of transcription 3) pathway. In the current study, we further elucidated the specific mechanism involved in TNF-?-induced astrogliogenesis. We found that TNF-? activated STAT3 at delayed time points (6 h and 24 h), whereas conditioned medium collected from TNF-?-treated NPCs induced an immediate STAT3 activation. These data suggest TNF-? plays an indirect role on STAT3 activation and the subsequent NPC differentiation. Further, we showed that TNF-? induced abundant amounts of the IL-6 family cytokines, including Leukemia inhibitory factor (LIF) and Interleukin 6 (IL-6), in human NPCs. TNF-?-induced STAT3 phosphorylation and astrogliogenesis were abrogated by the addition of neutralizing antibody for LIF, but not for IL-6, revealing a critical role of autocrine secretion of LIF in TNF-?-induced STAT3 activation and astrogliogenesis. This study generates important data elucidating the role of TNF-? in neurogenesis and may provide insight into new therapeutic strategies for brain inflammation.
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A novel, facile approach to frondosin B and 5-epi-liphagal via a new [4 + 3]-cycloaddition.
Org. Lett.
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A new [4 + 3]-cycloaddition between benzofuran allylic alcohols and dienes, promoted by camphorsulfonic acid, has been identified. A novel strategy which used this cycloaddition as a key step has been developed for the synthesis of 6,7,5-tricyclic skeleta, and syntheses toward frondosin B (1) and 5-epi-liphagal (2) have been achieved via short routes in good yields.
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Novel PNPLA2 gene mutations in Chinese Han patients causing neutral lipid storage disease with myopathy.
J. Hum. Genet.
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Neutral lipid storage disease with myopathy (NLSDM) referred to those neutral lipid storage disease (NLSD) patients with myopathy but without ichthyosis. Recently, NLSDM has been attributed to mutations in the PNPLA2 gene. Until now, 19 patients with PNPLA2 mutations have been reported. In the present study, we describe the clinical and genetic findings in three Chinese patients with NLSDM. Sequence analysis of PNPLA2 gene was performed. In our patients we identified four novel mutations in the PNPLA2 gene including two splicing mutations. The identification and study of mutations found in PNPLA2 is also particularly important to define the clinical spectrum and genotype-phenotype correlations of the PNPLA2 gene.
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Effect of polyethylene glycols on the alkaline-induced molten globule intermediate of bovine serum albumin.
Int. J. Biol. Macromol.
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In the present study, the formation of one molten globule-like unfolding intermediate of bovine serum albumin (BSA) at pH 11.2 has been established with the help of circular dichroism (CD) spectra, fluorescence spectroscopy and phase diagram approach. Additionally, we have shown the conformational changes occurring in the pH 11.2 intermediate of BSA when it was exposed to different molecular weight polyethylene glycols (PEGs) at varying concentrations. When the pH 11.2 intermediate of BSA was treated by PEG 400 there was induction of secondary and non-native tertiary contacts. In case of PEG 8000 and PEG 20,000, the loss in secondary as well as tertiary structure was observed. PEG 8000 and 20,000 altered the conformation of the pH 11.2 intermediate and resulted in its transition to another intermediate state in which the hydrophobic patches were inaccessible.
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Quantitative proteomic analysis of mouse embryonic fibroblasts and induced pluripotent stem cells using 16O/18O labeling.
J. Proteome Res.
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Induced pluripotent stem cells (iPSC) hold great promise for regenerative medicine as well as for investigations into the pathogenesis and treatment of various diseases. Understanding of key intracellular signaling pathways and protein targets that control development of iPSC from somatic cells is essential for designing new approaches to improve reprogramming efficiency. Here, we report the development and application of an integrated quantitative proteomics platform for investigating differences in protein expressions between mouse embryonic fibroblasts (MEF) and MEF-derived iPSC. This platform consists of 16O/18O labeling, multidimensional peptide separation coupled with tandem mass spectrometry, and data analysis with UNiquant software. With this platform, a total of 2481 proteins were identified and quantified from the 16O/18O-labeled MEF-iPSC proteome mixtures with a false discovery rate of 0.01. Among them, 218 proteins were significantly upregulated, while 247 proteins were significantly downregulated in iPSC compared to MEF. Many nuclear proteins, including Hdac1, Dnmt1, Pcna, Ccnd1, Smarcc1, and subunits in DNA replication and RNA polymerase II complex, were found to be enhanced in iPSC. Protein network analysis revealed that Pcna functions as a hub orchestrating complicated mechanisms including DNA replication, epigenetic inheritance (Dnmt1), and chromatin remodeling (Smarcc1) to reprogram MEF and maintain stemness of iPSC.
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BDNF and NT-3 expression by using glucocorticoid-induced bicistronic expression vector pGC-BDNF-IRES-NT3 protects apoptotic cells in a cellular injury model.
Brain Res.
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Spinal cord injury (SCI) is a severe traumatic disease in the central nervous system with high incidence and high morbidity. Recent study demonstrated that cell transplantation therapy may improve local microenvironment of the injury site and promote nerve regeneration to restore spinal cord functions. In this study, we constructed a glucocorticoid-induced bicistronic eukaryotic expression vector pGC-BDNF-IRES-NT3 by using molecular cloning techniques and examined the protective effect of neurotrophin-3 (NT-3) and brain-derived neurotrophic factor (BDNF) expressed by this vector in a rat spinal cord injury (SCI) model. We first connected glucocorticoid response element (GRE) to cytomegalovirus (CMV) promoter and then the GRE-CMV gene was inserted into pEGFP-1 vector to construct the eukaryotic expression vector pGC-EGFP. Western blot analysis was used to confirm the expression of EGFP by transfecting this vector in RN-DSC cells. The IRES was used to connect BDNF gene and NT-3 gene and replaced the EGFP gene in pGC-EGFP plasmid to form the bicistronic expression vector-pGC-BDNF-IRES-NT3. After RN-DSC cells were transfected with the plasmid and treated with glucocorticoid, BDNF and NT-3 expression in the culture medium were measured by ELISA method. Finally, we found that combination therapy with the transfection of this vector and glucocorticoid had an anti-apoptotic effect in a cellular SCI model of RN-DSC cells. Therefore, the co-expression of BDNF and NT-3 by using this vector rescued the injured cells. This provided useful information for the gene-modification cell transplantation combined with glucocorticoid for the treatment of SCI.
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A label-free oligonucleotide based thioflavin-T fluorescent switch for Ag+ detection with low background emission.
J Fluoresc
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A novel fluorescent Ag(+) sensor was developed based on the label-free silver (I) specific oligonucleotide (SSO) and Thioflavine T (ThT) monomer-excimer switch. C-rich SSO which contain C-C mismatched base pairs can selectively bind to Ag(+) ions and the formed duplexes which constructed by C-Ag(+)-C structure are thermally stabilized without largely altering the double helical structure. ThT give very weak fluorescent in bulk solution and/or in the presence of SSO. However ThT shows high fluorescence in the presence of SSO and Ag(+) at the same time mainly because ThT excimer, which has the high quantum yield, formed and stabilized in the minor or major groove. Based on the discovery, we developed the novel Ag(+) sensor. Under the optimum condition, the selectivity of this system for Ag(+) over other metal ions in aqueous solution is remarkably high, and Ag(+) can be quantified over the dynamic range of 30-450 nM, with a limit of detection of ~16 nM and a linear correlation coefficient of 0.995.
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What is Visualize?

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

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

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.