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Find video protocols related to scientific articles indexed in Pubmed.
Use of diffusion tensor imaging in assessing superficial myometrial invasion by endometrial carcinoma: a preliminary study.
Acta Radiol
PUBLISHED: 10-22-2014
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Magnetic resonance imaging (MRI) remains the standard modality for local staging of gynecological malignancies, but it has several limitations, especially when differentiating a cancer limited to the endometrium from a cancer invading the superficial myometrium.
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Global and local persistence of influenza A(H5N1) virus.
Emerging Infect. Dis.
PUBLISHED: 07-26-2014
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An understanding of the global migration dynamics of highly pathogenic avian influenza A(H5N1) virus is helpful for surveillance and disease prevention. To characterize the migration network of this virus, we used genetic analysis, which supported a global persistence model in which each of 9 regions acts to some extent as a source. Siberia is the major hub for the dispersal of the virus. Southeast Asia and Africa are major sources of genetically and antigenically novel strains. We found evidence of local persistence of the virus in Southeast Asia and Africa, which is rare for human influenza A viruses. The differences in migration dynamics between avian and human influenza viruses might help with the design of region-specific surveillance efforts and the selection of vaccine candidates.
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TRAF4 participates in Wnt/?-catenin signaling in breast cancer by upregulating ?-catenin and mediating its translocation to the nucleus.
Mol. Cell. Biochem.
PUBLISHED: 06-17-2014
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Tumor necrosis factor receptor-associated factor 4 (TRAF4) is upregulated in various subtypes of breast cancers and cell lines; however, the precise functions of TRAF4 are poorly understood. Our objective was to investigate its relationship with ?-catenin. TRAF4 participates in several signaling pathways, such as NF-?B and JNK signaling pathways. In this study, we identified ?-catenin as a TRAF4-binding protein, have shown that TRAF4 enhanced expression of ?-catenin, and found that TRAF4 mediated the translocation of ?-catenin from the cytoplasm to the nucleus, thereby facilitating activation of the Wnt signaling pathway in breast cancer.
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Application of response surface methodology to optimise supercritical carbon dioxide extraction of volatile compounds from Crocus sativus.
J. Sci. Food Agric.
PUBLISHED: 05-17-2014
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Crocus sativus has been used as a traditional Chinese medicine for a long time. The volatile compounds of C. sativus appear biologically active and may act as antioxidants as well as anticonvulsants, antidepressants and antitumour agents. In order to obtain the highest possible yield of essential oils from C. sativus, response surface methodology was employed to optimise the conditions of supercritical fluid carbon dioxide extraction of the volatile compounds from C. sativus. Four factorswere investigated: temperature, pressure, extraction time and carbon dioxide flow rate. Furthermore, the chemical compositions of the volatile compounds extracted by supercritical fluid extraction were compared with those obtained by hydro-distillation and Soxhlet extraction.
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Transcription Factor STAT3 as a Novel Molecular Target for Cancer Prevention.
Cancers (Basel)
PUBLISHED: 03-11-2014
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Signal Transducers and Activators of Transcription (STATs) are a family of transcription factors that regulate cell proliferation, differentiation, apoptosis, immune and inflammatory responses, and angiogenesis. Cumulative evidence has established that STAT3 has a critical role in the development of multiple cancer types. Because it is constitutively activated during disease progression and metastasis in a variety of cancers, STAT3 has promise as a drug target for cancer therapeutics. Recently, STAT3 was found to have an important role in maintaining cancer stem cells in vitro and in mouse tumor models, suggesting STAT3 is integrally involved in tumor initiation, progression and maintenance. STAT3 has been traditionally considered as nontargetable or undruggable, and the lag in developing effective STAT3 inhibitors contributes to the current lack of FDA-approved STAT3 inhibitors. Recent advances in cancer biology and drug discovery efforts have shed light on targeting STAT3 globally and/or specifically for cancer therapy. In this review, we summarize current literature and discuss the potential importance of STAT3 as a novel target for cancer prevention and of STAT3 inhibitors as effective chemopreventive agents.
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Discovery of potent anticancer agent HJC0416, an orally bioavailable small molecule inhibitor of signal transducer and activator of transcription 3 (STAT3).
Eur J Med Chem
PUBLISHED: 03-10-2014
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In a continuing effort to develop orally bioavailable small-molecule STAT3 inhibitors as potential therapeutic agents for human cancer, a series of novel diversified analogues based on our identified lead compound HJC0149 (1) (5-chloro-N-(1,1-dioxo-1H-1?(6)-benzo[b]thiophen-6-yl)-2-hydroxybenzamide, Eur. J. Med. Chem. 2013, 62, 498-507) have been rationally designed, synthesized, and pharmacologically evaluated. Molecular docking studies and biological characterization supported our earlier findings that the O-alkylamino-tethered side chain on the hydroxyl group is an effective and essential structural determinant for improving biological activities and druglike properties of these molecules. Compounds with such modifications exhibited potent antiproliferative effects against breast and pancreatic cancer cell lines with IC50 values from low micromolar to nanomolar range. Among them, the newly discovered STAT3 inhibitor 12 (HJC0416) displayed an intriguing anticancer profile both in vitro and in vivo (i.p. & p.o.). More importantly, HJC0416 is an orally bioavailable anticancer agent as a promising candidate for further development.
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Analysis of volatile components extracted from the peels of four different Chinese pomelos using TDS-GC-MS.
J. Sci. Food Agric.
PUBLISHED: 03-10-2014
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The rational utilization of the resources of Chinese pomelo peels requires reliable fast evaluation methods for their quality. However, how to improve the accuracy of prediction of the volatile organic compounds in the peels is not well addressed. In this study dynamic headspace collection combined with thermal desorption system/cold trap injection and gas chromatography-mass spectrometry (TDS-GC-MS) was employed to examine the volatile organic compounds in the peels of four different types of Chinese pomelos.
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A novel role for interferon regulatory factor 1 (IRF1) in regulation of bone metabolism.
J. Cell. Mol. Med.
PUBLISHED: 02-18-2014
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Increased risk of bone fractures is observed in patients with chronic inflammatory conditions, such as inflammatory bowel disease and rheumatoid arthritis. Members of the Interferon Response Factor family of transcriptional regulators, IRF1 and IRF8, have been identified as genetic risk factors for several chronic inflammatory and autoimmune diseases. We have investigated a potential role for the Irf1 gene in bone metabolism. Here, we report that Irf1(-/-) mutant mice show altered bone morphology in association with altered trabecular bone architecture and increased cortical thickness and cellularity. Ex vivo studies on cells derived from bone marrow stimulated with Rank ligand revealed an increase in size and resorptive activity of tartrate-resistant acid-positive cells from Irf1(-/-) mutant mice compared with wild-type control mice. Irf1 deficiency was also associated with decreased proliferation of bone marrow-derived osteoblast precursors ex vivo, concomitant with increased mineralization activity compared with control cells. We show that Irf1 plays a role in bone metabolism and suggest that Irf1 regulates the maturation and activity of osteoclasts and osteoblasts. The altered bone phenotype of Irf1(-/-) mutants is strikingly similar to that of Stat1(-/-) mice, suggesting that the two interacting proteins play a critical enabling role in the common regulation of these two cell lineages.
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Antitumor and immunomodulatory effects of low-dose 5-FU on hepatoma 22 tumor-bearing mice.
Oncol Lett
PUBLISHED: 02-06-2014
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Low-dose 5-fluorouracil (5-FU), a widely used chemotherapeutic, has been reported to have immunomodulatory effects. This study aimed to evaluate the optimal dose of 5-FU that produces antitumor and immunomodulatory effects. In a hepatoma 22 tumor-bearing mouse model, 0, 10, 20 and 40 mg/kg 5-FU (i.p.) was administered for 10 days. Tumor weight and volume were measured, thymus index (TI) and spleen index (SI) were calculated, and the number of white blood cells (WBCs) and lymphocytes (LYs) were counted following treatment. The percentages of CD3(+), CD4(+), CD8(+) and natural killer (NK) cells were measured by flow cytometry. In addition, the body weights of the mice were measured and the average diet consumption was calculated. Administration of 5-FU produced a potent antitumor effect in a dose-dependent manner (P<0.01). At 20 and 40 mg/kg, a significant reduction of body weight and food consumption was observed. TI and SI decreased in the 20- and 40-mg/kg groups (P<0.01) for 10 days. The number of WBCs significantly decreased in each group (P<0.01); however, the number of LYs only decreased in the 40-mg/kg group (P<0.01). Percentages of CD3(+) and CD4(+) cells were increased in the 10- and 20-mg/kg groups (P<0.01). Thus, 5-FU at 10 mg/kg inhibits tumor growth while maintaining the immune function of the mice. 5-FU may exert its antitumor effect at a low dose with low toxicity and stimulate the host immune system. Future clinical trials taking into account the immunostimulatory capacity of chemotherapeutic agents are desirable for certain patients.
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Differentiation of osteolytic metastases and Schmorl's nodes in cancer patients using dual-energy CT: advantage of spectral CT imaging.
Eur J Radiol
PUBLISHED: 02-03-2014
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To assess the reliability of dual-energy CT (DECT) spectral imaging for the differentiation of bone metastases (BMs) from Schmorl's nodes (SNs) in the vertebrae of cancer patients.
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The hepatocyte phase of Gd-EOB-DTPA-enhanced MRI in the evaluation of hepatic fibrosis and early liver cirrhosis in a rat model: an experimental study.
Life Sci.
PUBLISHED: 02-01-2014
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To evaluate the hepatocyte phase of Gd-EOB-DTPA-enhanced MRI in the early diagnosis of hepatic fibrosis and cirrhosis and assessment of liver function in a rat model.
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Nanopore film based enrichment and quantification of low abundance hepcidin from human bodily fluids.
Nanomedicine
PUBLISHED: 01-29-2014
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Endogenous peptides that represent biological and pathological information of disease have attracted interest for diagnosis. However, the extraction of those low abundance peptides is still a challenge because of the complexity of human bodily fluids (HBF). Hepcidin, a peptide hormone, has been recognized as a biomarker for iron-related diseases. There is no rapid and reliable way to enrich them from HBF. Here we describe a peptide extraction approach based on nanoporous silica thin films to successfully detect hepcidin from HBF. Cooperative functions of nanopore to biomolecule, including capillary adsorption, size-exclusion and electrostatic interaction, were systematically investigated to immobilize the target peptide. To promote this new approach to clinical practices, we further applied it to successfully assay the hepcidin levels in HBF provided by healthy volunteers and patients suffering from inflammation. Our finding provides a high-throughput, rapid, label-free and cost-effective detection method for capturing and quantifying low abundance peptides from HBF.
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The joint effects of room temperature ionic liquids and ordered media on fluorescence characteristics of estrogens in water and methanol.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 01-23-2014
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This study investigated the steady-state and time-resolved fluorescence properties of 17?-ethinylestradiol (EE2) and 17?-estradiol (E2) in the presence of ordered media (?-cyclodextrins (?-CD) and cetyltrimethylammonium bromide (CTAB)). In addition, we analyzed the effects of four room temperature ionic liquids (RTILs) on the fluorescence intensities (FIs) of EE2/?-CD and E2/?-CD inclusion complexes in methanol. Both ?-CD and CTAB enhanced the fluorescence of EE2 and E2. The FIs of EE2 and E2 with ?-CD or CTAB in methanol were greater than those in water, possibly resulting from decreased oxygen-quenching in H2O molecules. ?-CD and CTAB may form inclusion complexes with estrogen in both water and methanol. The inclusion ratio of the complex was 1:1 and the inclusion constant (K) values in water were greater than those in methanol. The fluorescence lifetimes were 2.50 and 4.13 ns for EE2 and 2.58 and 4.03 ns for E2 in aqueous solution and methanol, respectively. The changing trend of fluorescence lifetimes for EE2 and E2 in ?-CD or CTAB was similar to the steady-state FIs. The four RTILs had a significant quenching effect on the FIs of EE2/?-CD and E2/?-CD, and the quenching process for EE2/?-CD and E2/?-CD by RTILs was demonstrated to be a dynamic quenching mechanism. Fluorescent data obtained from these complex systems provide a theoretical foundation for understanding the interaction mechanisms between ordered media and RTILs in the analysis of estrogens.
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Utility of R2* obtained from T2*-weighted imaging in differentiating hepatocellular carcinomas from cavernous hemangiomas of the liver.
PLoS ONE
PUBLISHED: 01-01-2014
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To evaluate the feasibility of applying R2* values to differentiate hepatocellular carcinomas (HCC) from cavernous hemangiomas of the liver (CHL).
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The detection and elimination of flavin-containing monooxygenase 3 gene T329S mutation in the Beijing You chicken.
Poult. Sci.
PUBLISHED: 11-16-2013
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In this study, using a newly developed TaqMan-based real-time PCR method for the T329S mutation in the flavin-containing monooxygenase 3 (FMO3) gene, a marker-assisted selective breeding program against the unfavorable T allele was implemented in the Beijing You chicken breeding stock from 2010 to 2012. A total of 2,359 breeder candidate chickens were detected. After 1-generation culling in both males and females and 2-generation culling only in males, genotyping results in 2013 showed that there still remained a low unfavorable allele frequency of 0.022 in this population. The results indicated that to ensure a complete eradication of the defective tainting mutation in FMO3 out of the Beijing You population, more strict breeding and management schemes should be carried out in the future.
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Adenylyl Cyclase 6 Activation Negatively Regulates TLR4 Signaling through Lipid Raft-Mediated Endocytosis.
J. Immunol.
PUBLISHED: 11-11-2013
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Proper intracellular localization of TLRs is essential for their signaling and biological function. Endocytosis constitutes a key step in protein turnover, as well as maintenance of TLR localization in plasma membrane and intracellular compartments, and thus provides important regulating points to their signaling. In this study, we demonstrate that adenylyl cyclase (AC) activation attenuates TLR4 signaling in a murine macrophage cell line (RAW 264.7) and bone marrow-derived macrophages when stimulated with LPS. We further show that the AC6 isoform plays a key role in negative regulation of TLR4 signaling by promoting protein degradation. TLR4 is normally endocytosed through the clathrin-mediated pathway, but concomitant AC6 activation shifts it to lipid raft-mediated endocytosis, which accelerates degradation of TLR4 and suppresses downstream signaling. Our studies unveil a new mechanism of negative regulation of TLR4 signaling through AC6-mediated endocytosis, which might provide a novel therapeutic approach for limiting inflammatory and autoimmune diseases.
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Oridonin ring a-based diverse constructions of enone functionality: identification of novel dienone analogues effective for highly aggressive breast cancer by inducing apoptosis.
J. Med. Chem.
PUBLISHED: 10-31-2013
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Oridonin (1) has attracted considerable attention in recent years because of its unique and safe anticancer pharmacological profile. Nevertheless, it exhibits moderate to poor effects against highly aggressive cancers including triple-negative and drug-resistant breast cancer cells. Herein, we report the rational design and synthesis of novel dienone derivatives with an additional ?,?-unsaturated ketone system diversely installed in the A-ring based on this class of natural scaffold that features dense functionalities and stereochemistry-rich frameworks. Efficient and regioselective enone construction strategies have been established. Meanwhile, a unique 3,7-rearrangement reaction was identified to furnish an unprecedented dienone scaffold. Intriguingly, these new analogues have been demonstrated to significantly induce apoptosis and inhibit colony formation with superior antitumor effects against aggressive and drug-resistant breast cancer cells in vitro and in vivo while also exhibiting comparable or lower toxicity to normal human mammary epithelial cells in comparison with 1.
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MoO2-ordered mesoporous carbon hybrids as anode materials with highly improved rate capability and reversible capacity for lithium-ion battery.
Phys Chem Chem Phys
PUBLISHED: 07-09-2013
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A novel hybrid of MoO2-ordered mesoporous carbon (MoO2-OMC) was prepared through a two-step solvothermal chemical reaction route. The electrochemical performances of the mesoporous MoO2-OMC hybrids were examined using galvanostatical charge-discharge, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS) techniques. The MoO2-OMC hybrid exhibits significantly improved electrochemical performance of high reversible capacity, high-rate capability, and excellent cycling performance as an anode electrode material for Li ion batteries. It is revealed that the MoO2-OMC hybrid could deliver the first discharge capacity of 1641.8 mA h g(-1) with an initial Coulombic efficiency of 63.6%, and a reversible capacity as high as 1049.1 mA h g(-1) even after 50 cycles at a current density of 100 mA g(-1), much higher than the theoretical capacity of MoO2 (838 mA h g(-1)) and OMC materials. The MoO2-OMC hybrid demonstrates an excellent high rate capability with capacity of ?600 mA h g(-1) even at a charge current density of 1600 mA g(-1) after 50 cycles, which is approximately 11.1 times higher than that of the OMC (54 mA h g(-1)) materials. The improved rate capability and reversible capacity of the MoO2-OMC hybrid are attributed to a synergistic reaction between the MoO2 nanoparticles and mesoporous OMC matrices. It is noted that the electrochemical performance of the MoO2-OMC hybrid is evidently much better than the previous MoO2-based hybrids.
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[Direct secretory expression of active microbial transglutaminase in Pichia pastoris].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 05-24-2013
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Direct secretory expression of active microbial transglutaminase (MTG) using heterologous hosts is a promising strategy, although its production level still needs to be improved for industrial production. Pichia pastoris is one of the most efficient expression systems developed in recent years. In this study, secretory expression of active MTG was successfully achieved by co-expressing the pro sequence and mature MTG genes in P. pastoris. Furthermore, we optimized the copy number of pro/MTG expression cassettes and the fermentation conditions. MTG production level reached 7.3 U/mL in 1-liter fermentor through high density fermentation, providing the feasiblity for industrial scale preparation of MTG.
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[Function of nitric oxide in initiating production of lignin degrading peroxidases by Phanerochaete chrysosporium].
Wei Sheng Wu Xue Bao
PUBLISHED: 05-18-2013
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By analyzing the function and mechanism of nitric oxide in initiating producing lignin peroxidases by phanerochaete chrysosporium, we studied the regulation mechanism triggering the secondary metabolism of white-rot fungi.
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[Effect of Staphylococcus aureus on the expressions of TLR2, IL-1?, TNF-? and NF-?B in Bcap-37 cells].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 05-07-2013
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To observe the effects of Staphylococcus aureus (S.aureus) on the expressions of Toll-like receptor 2 (TLR2), proinflammatory cytokines (IL-1?, TNF-?) and nuclear factor ?B(NF-?B) in human breast cancer Bcap-37 cells in vitro.
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Functional analysis and expressional characterization of rice ankyrin repeat-containing protein, OsPIANK1, in basal defense against Magnaporthe oryzae attack.
PLoS ONE
PUBLISHED: 02-17-2013
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The ankyrin repeat-containing protein gene OsPIANK1 (AK068021) in rice (Oryza sativa L.) was previously shown to be upregulated following infection with the rice leaf blight pathogen Xanthomonas oryzae pv oryzae (Xoo). In this study, we further characterized the role of OsPIANK1 in basal defense against Magnaporthe oryzae (M.oryzae) by 5 deletion analysis of its promoter and overexpression of the gene. The promoter of OsPIANK1 with 1,985 bps in length was sufficient to induce the OsPIANK1 response to inoculation with M.oryzae and to exogenous application of methyl jasmonate (MeJA) or salicylic acid (SA), but not to exogenous application of abscisic acid (ABA). A TCA-element present in the region between -563 bp and -249 bp may be responsible for the OsPIANK1 response to both M.oryzae infection and exogenous SA application. The JERE box, CGTCA-box, and two MYB binding sites locating in the region between -1985 bp and -907 bp may be responsible for the response of OsPIANK1 to exogenous MeJA. OsPIANK1 expression was upregulated after inoculation with M.oryzae and after treatment with exogenous SA and MeJA. Overexpression of OsPIANK1 enhanced resistance of rice to M.oryzae, although it did not confer complete resistance. The enhanced resistance to M.oryzae was accompanied by enhanced transcriptional expression of SA- and JA-dependent genes such as NH1, WKRY13, PAL, AOS2, PR1b, and PR5. This evidence suggests that OsPIANK1 acted as a positive regulator in rice basal defense mediated by SA- and JA-signaling pathways.
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Toxicity evaluation of ?-diketone antibiotics on the development of embryo-larval zebrafish (danio rerio).
Environ. Toxicol.
PUBLISHED: 01-30-2013
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This study evaluated the effects of ?-diketone antibiotics (DKAs) on the development of embryo-larval zebrafish (Danio rerio). When exposure to DKAs, developmental malformations, such as hatching delay, curved body axis, pericardial edema, uninflated swim bladder and yolk sac edema, were observed at 120 h postfertilization (hpf). The estimated 120 hpf nominal concentrations of no observed effect concentration and lowest observed effect concentration for DKAs were 18.75 and 37.50 mg/L, respectively, suggesting that DKAs have much lower toxicity than other persistent pollutants. Following DKA exposure, embryonic heart rates were significantly reduced as compared to the controls at 48 and 60 hpf. The peak bending motion frequency appeared 1 h earlier than in control embryos. The 2.34 and 9.38-mg/L treatment groups had a higher basal swim rate than control groups at 120 hpf in both light and light-to-dark photoperiod experiments. The occurrence of high speed swim rates was enhanced approximately threefold to sevenfold in the 2.34 and 9.38 mg/L treatments compared to the control. Glutathione (GSH) concentrations in the 2.34 and 9.38-mg/L treatments were significantly higher than the control at 72 hpf, suggesting that GSH production was induced at the end of the hatching period. When exposed to DKAs, zebrafish superoxide dismutase enzyme (SOD) activities were significantly inhibited in the early embryonic period, demonstrating that the clearing ability in zebrafish was lower than the generation rate of free radicals. In summary, the combined DKAs were developmentally toxic to zebrafish in their early life stages and had the ability to impair individual behaviors that are of great importance in the assessment of their ecological fitness. © 2013 Wiley Periodicals, Inc. Environ Toxicol, 2013.
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Risk factors for and prevalence of knee osteoarthritis in the rural areas of Shanxi Province, North China: a COPCORD study.
Rheumatol. Int.
PUBLISHED: 01-29-2013
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The purpose of this study is to investigate the prevalence of knee osteoarthritis (OA) in the rural areas of Shanxi Province, North China. A total of 7,126 permanent residents aged from 16 to 90 years were surveyed using Community Oriented Program for the Control of Rheumatic Diseases methodology. Diagnosis of knee OA was reached according to the examination results by 3 rheumatologists. Possible risk factors for knee OA were analyzed. Among the 7,126 participants, 983 cases were diagnosed with knee OA. Of the 983 cases, 446 were male (12.4%) and 537 were female (15.3%). The overall prevalence of knee OA was 13.8%. The prevalence rate of knee pain was significantly higher in women than in men. There was a tendency of increased knee OA prevalence with age, especially after 40 years old. Participants with higher body mass index (BMI) showed a higher prevalence rate of knee OA than those with lower BMI. Multivariable analysis indicates age, gender, dietary bias, underground work history, BMI, waist-to-hip ratio (WHR), and concomitant cardiovascular diseases (CSDs) are risk factors for knee OA in rural Shanxi. The prevalence of knee OA in the rural areas of Shanxi Province is high. Age, gender, dietary bias, underground work history, BMI, WHR, and CSDs are risk factors for knee OA. Primary and secondary prevention programs aimed at improving ventilation condition, reducing obesity, and treating concomitant cardiovascular diseases are required.
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Humic acid removal and easy-cleanability using temperature-responsive ZrO2 tubular membranes grafted with poly(N-isopropylacrylamide) brush chains.
Water Res.
PUBLISHED: 01-27-2013
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New poly(N-isopropylacrylamide) brushes grafted with ZrO2 (PNIPAAm-g-ZrO2) composite membranes, which had been prepared in our laboratory, were used for humic acid (HA) removal. We found that the fluxes associated with such membranes, when compared to those obtained from unmodified ZrO2 membranes, declined slightly at both 25 °C and 35 °C. The PNIPAAm-g-ZrO2 membrane achieved a high rejection, of 98.0%, at a suitable steady flux of 111.9 L m(-2) h(-1) at 25 °C. This membrane exhibited good anti-fouling properties as well as improved membrane performance during filtration of HA. The important role of pH and Ca(2+) concentration in HA removal was also investigated. Lower adsorption fouling and a higher rejection were obtained at higher pH levels. The Ca(2+) ions reduced the electrostatic exclusion and played a cross-linking role between HA and the PNIPAAm-g-ZrO2 membrane surface. Fouling was severe in the presence of Ca(2+). These tests led to the development of an environment-friendly membrane cleaning method, by means of temperature-change water elution around LCST of PNIPAAm-brushes. After the alternate temperature-change (25 °C/35 °C) cleaning, a flux recovery of 98.2% was obtained for the PNIPAAm-g-ZrO2 membrane. Moreover, after four repeated experiments, the anti-fouling and easy-cleaning properties were still maintained. It is implied that PNIPAAm-brushes were firmly "stuck" to the membrane surface, and could not easily be removed by water cleaning or HA filtration. The PNIPAAm-g-ZrO2 membranes exhibited good stability and great potential for HA removal.
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Identification of a lead small-molecule inhibitor of anthrax lethal toxin by using fluorescence-based high-throughput screening.
BMB Rep
PUBLISHED: 12-23-2011
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Inhalational anthrax is caused by B. anthracis, a virulent sporeforming bacterium which secretes anthrax toxins consisting of protective antigen (PA), lethal factor (LF) and edema factor (EF). LF is a Zn-dependent metalloprotease and is the main determinant in the pathogenesis of anthrax. Here we report the identification of a lead small-molecule inhibitor of anthrax lethal factor by screening an available synthetic small-molecule inhibitor library using fluorescence-based high-throughput screening (HTS) approach. Seven small molecules were found to have inhibitory effect against LF activity, among which SM157 had the highest inhibitory activity. All theses small molecule inhibitors inhibited LF in a noncompetitive inhibition mode. SM157 and SM167 are from the same family, both having an identical group complex, which is predicted to insert into S1 pocket of LF. More potent small-molecule inhibitors could be developed by modifying SM157 based on this identical group complex.
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[Variation of monosacchride composition of polysacchrides in Dendrobium officinale by pre-column derivatization HPLC method].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 10-01-2011
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The monosacchride composition of polysacchrides in Dendrobium officinal of different germplasms, physiological ages and closely related species were determined by pre-column derivatization HPLC. The results showed that the absolute and relative volumes of all monosacchrides were significantly different between D. officinale and its closely related species, different germplasms and physiological ages of D. officinale. Absolute peak areas of mannose ranged from 0.854 x 10(7) to 10.340 x 10(7) in closely related species of D. officinale, ranged from 1.467 x 10(7) to 8.475 x 10(7) in different germplasms of D. officinale and were 4.411 x 10(7) (2.577 x 10(7)-6.516 x 10(7)), 5.528 x 10(7) (3.179 x 10(7)-8.475 x 10(7)) and 3.601 x 10(7) (1.467 x 10(7)-5.888 x 10(7)), respectively, in one to three physiological ages of D. officinale. The ratio of mannose to glucose peak areas (relative peak area) ranged from 0.976 to 16.599 in closely related species of D. officinale and from 2.679 to 7.831 in different germplasms of D. officinale. Only the relative peak areas of D. pendulum and D. primulinum were in the range of different germplasms of D. officinale in all tested samples. The results revealed the variation of monosacchride composition of polysacchrides in D. officinale. Monosacchride composition of D. officinale could be altered by breeding new varieties and controlling harvesting season. Most adulterants of D. officinale could be ruled out according to the relative peak areas of D. officinale, providing a basis for quality control and resources training of D. officinale.
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A chemical genomics screen to discover genes that modulate neural stem cell differentiation.
J Biomol Screen
PUBLISHED: 09-23-2011
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The authors designed a chemical genomics screen with the aim of understanding genes and pathways that modulate neural stem/precursor cell differentiation. Multipotent mouse neural precursor cells isolated from cortices of embryonic day 12 (E12) embryos were subjected to spontaneous differentiation triggered by growth factor withdrawal. A quantitative whole-well immunofluorescence assay was set up to screen tool compound sets to identify small molecules with potent, dose-dependent, and reproducible effects on increasing neural stem cell differentiation toward neuronal lineage. Among the pro-neuronal compounds, kinase inhibitors were shown to exert pro-neuronal effect via a signaling pathway associated with the kinase. The global effect of hit compounds on modulating neuronal differentiation was confirmed by an in vivo mouse study and human neural stem cells culture. This study demonstrates that a phenotypic assay using cell type-specific antibody markers can be used for a large-scale compound screen to discover targets and pathways with impacts on differentiation of lineage-restricted precursor cells toward specific lineages.
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[Study on basic amino acid contents in Dendrobium officinale].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 06-28-2011
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To investigate the contents of 16 basic amino acid and find out the variation of them in Dendrobium officinale with different germplasms and physiological ages, and then provide scientific basis for the quality evaluation and the breeding of D. officinale.
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[Breeding and characterization of laccase-producing Phanerochaete chrysosporium mutant resistant to nutritional repression].
Wei Sheng Wu Xue Bao
PUBLISHED: 05-25-2011
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To screen Phanerochaete chrysosporium mutants resisting nutritional repression and to characterize laccase produced by the mutants.
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[Study on 11 metal [correction of mental] element contents in Dendrobium officinale].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 05-19-2011
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To find out the variation of 11 mental element contents in Dendrobium officinale with different germplasms and harvesting ages, the results can provide scientific basis for the quality evaluation and the breeding of D. officinale.
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High levels of adenosine deaminase on dendritic cells promote autoreactive T cell activation and diabetes in nonobese diabetic mice.
J. Immunol.
PUBLISHED: 05-18-2011
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Adenosine has been established as an important regulator of immune activation. It signals through P1 adenosine receptors to suppress activation of T cells and professional APCs. Adenosine deaminase (ADA) counters this effect by catabolizing adenosine. This regulatory mechanism has not been tested in a disease model in vivo. Questions also remain as to which cell types are most sensitive to this regulation and whether its dysregulation contributes to any autoimmune conditions. We approached this issue using the NOD model. We report that ADA is upregulated in NOD dendritic cells, which results in their exuberant and spontaneous activation. This, in turn, triggers autoimmune T cell activation. NOD DCs deficient in ADA expression have a greatly reduced capacity to trigger type I diabetes. We also provide evidence that although many cell types, particularly T cells, have been implicated as the suppression targets by adenosine in an in vitro setting, DCs also seem to be affected by this regulatory mechanism. Therefore, this report illustrates a role of ADA in autoimmunity and suggests a potential target for therapeutic intervention.
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Effective NH2-grafting on attapulgite surfaces for adsorption of reactive dyes.
J. Hazard. Mater.
PUBLISHED: 03-03-2011
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The amine moiety has an important function in many applications, including, adsorption, catalysis, electrochemistry, chromatography, and nanocomposite materials. We developed an effective adsorbent for aqueous reactive dye removal by modifying attapulgite with an amino-terminated organosilicon (3-aminopropyltriethoxysilane, APTES). Surface properties of the APTES-modified attapulgite were characterized by the Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption-desorption. We evaluated the impact of solvent, APTES concentration, water volume, reaction time, and temperature on the surface modification. NH(2)-attapulgite was used to remove reactive dyes in aqueous solution and showed very high adsorption rates of 99.32%, 99.67%, and 96.42% for Reactive Red 3BS, Reactive Blue KE-R and Reactive Black GR, respectively. These powerful dye removal effects were attributed to strong electrostatic interactions between reactive dyes and the grafted NH(2) groups.
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Intranasal co-administration with the mouse zona pellucida 3 expressing construct and its coding protein induces contraception in mice.
Vaccine
PUBLISHED: 01-22-2011
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The zona pellucida 3 (ZP3), an autoantigen, once used to develop contraceptive vaccine has been faced a safety issue. Avoiding its pathogenic T cell activation, we intranasally co-delivered the mZP3 DNA- and protein-based vaccines in mice and observed that a higher level of sIgA and IgG antibodies in vaginal washes, bronchoalveolar lavages and serum and yielded a lower level of fertility and mean litter size. Importantly, histological analysis showed that normal follicular developments of the infertile mice were not disrupted in the co-delivered group. Thus, the intranasal co-delivery may present a safe strategy for the development of contraceptive vaccine.
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Leukemia inhibitory factor inhibits T helper 17 cell differentiation and confers treatment effects of neural progenitor cell therapy in autoimmune disease.
Immunity
PUBLISHED: 01-10-2011
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Neural progenitor cell (NPC) therapy is considered a promising treatment modality for multiple sclerosis (MS), potentially acting through neural repair. Here, we showed that intravenous administration of NPCs ameliorated experimental autoimmune encephalomyelitis (EAE) by selectively inhibiting pathogenic T helper 17 (Th17) cell differentiation. Leukemia inhibitory factor (LIF) produced by NPCs was responsible for the observed EAE suppression. Through the inducible LIF receptor expression, LIF inhibited the differentiation of Th17 cells in EAE mice and that from MS subjects. At the molecular level, LIF exerted an opposing effect on interleukin 6 (IL-6)-induced signal transducer and activator of transcription 3 (STAT3) phosphorylation required for Th17 cell differentiation by triggering a signaling cascade that activated extracellular signal-regulated MAP kinase (ERK) and upregulated suppressor of cytokine signaling 3 (SOCS3) expression. This study reveals a critical role for LIF in regulating Th17 cell differentiation and provides insights into the mechanisms of action of NPC therapy in MS.
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[Quantitative variation of total alkaloids contents in Dendrobium officinale].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 12-15-2010
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To investigate the total alkaloid content and find out the variation of total alkaloids content in Dendrobium officinale with different germplasms and harvesting ages with the aim of providing scientific basis for the authenticity identification and the breeding of D. officinale.
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Characterization of a novel beta-xylosidase, XylC, from Thermoanaerobacterium saccharolyticum JW/SL-YS485.
Appl. Environ. Microbiol.
PUBLISHED: 12-03-2010
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The 1,914-bp open reading frame of xylC from Thermoanaerobacterium saccharolyticum JW/SL-YS485 encodes a calculated 73-kDa ?-xylosidase, XylC, different from any glycosyl hydrolase in the database and representing a novel glycohydrolase family. Hydrolysis occurred under retention of the anomeric configuration, and transglycosylation occurred in the presence of alcohols as acceptors. With the use of vector pHsh, expression of XylC, the third ?-xylosidase in this bacterium, increased approximately 4-fold when a loop within the translational initiation region in the mRNA was removed by site-directed mutagenesis. The increased expression of xylC(m) is due to removal of a stem-loop structure without a change of the amino acid sequence of the heterologously expressed enzyme (XylC(rec)). When gel filtration was applied, purified XylC had molecular masses of 210 kDa and 265 kDa using native gradient gel electrophoresis. The protein consisted of 78-kDa subunits based on SDS gel electrophoresis and contained 6% carbohydrates. XylC and XylC(rec) exhibited maximum activity at 65°C and pH(65°C) 6.0, a 1-h half-life at 67°C, a K(m) for p-nitrophenyl-?-D-xyloside of 28 mM, and a V(max) of 276 U/mg and retained 70% activity in the presence of 200 mM xylose, suggesting potential for industrial applications.
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Virulence factor cytotoxin-associated gene A in Helicobacter pylori is downregulated by interferon-? in vitro.
FEMS Immunol. Med. Microbiol.
PUBLISHED: 11-10-2010
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Helicobacter pylori-infected gastric mucosa is characterized by high levels of interferon-? (IFN-?), but whether the high level of IFN-? regulates the virulence of H. pylori is unclear. Here, we characterized the response of H. pylori to IFN-? and found by indirect immunofluorescence that IFN-? can bind to H. pylori. The binding resulted in the altered expression of 14 proteins, including the virulence factor, cytotoxin-associated gene A (CagA), whose expression was downregulated. The transcription and translation of CagA downregulated by IFN-? was further confirmed by reverse transcriptase-PCR and Western blot analysis. We co-cultured the human gastric cancer cell line AGS with H. pylori exposed to IFN-?; both phosphorylated CagA and nonphosphorylated CagA in AGS cells were downregulated by IFN-?, and the proportion of cells with the hummingbird phenotype was also decreased. Thus, IFN-? can help control H. pylori infection indirectly through the virulence factor CagA.
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?-TEA induces apoptosis of human breast cancer cells via activation of TRAIL/DR5 death receptor pathway.
Mol. Carcinog.
PUBLISHED: 10-02-2010
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Vitamin E derivative RRR-?-tocopherol ether-linked acetic acid analog (?-TEA) induces apoptosis in MCF-7 and HCC-1954 human breast cancer cells in a dose- and time-dependent manner. ?-TEA induces increased levels of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and death receptor-5 (DR5) and decreased levels of antiapoptotic factor, cellular FLICE-like inhibitory protein (c-FLIP L). DR5/TRAIL induced apoptosis involves downregulation of c-FLIP (L), caspase-8 activation, activated proapoptotic mediators tBid and Bax, mitochondrial permeability transition, and activation of caspase-9. siRNA knockdown of either DR5 or TRAIL blocks the ability of ?-TEA to enhance DR5 protein levels, downregulate c-FLIP(L) protein levels and induce apoptosis. Combination of ?-TEA?+?TRAIL acts cooperatively to induce apoptosis, and increase DR5 and decrease c-FLIP (L) protein levels. siRNA knockdown of c-FLIP produces a low level of spontaneous apoptosis and enhances ?-TEA- and TRAIL-induced apoptosis. Taken together, these studies show that ?-TEA induces TRAIL/DR5 mitochondria-dependent apoptosis in human breast cancer cells, and that TRAIL/DR5-dependent increases in DR5 and decreases in c-FLIP expression are triggered by TRAIL or ?-TEA treatments.
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Fibroblast immuno-diagnosis of cytochrome oxidase (COX) deficiency in mitochondrial disease.
Mitochondrion
PUBLISHED: 08-27-2010
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We studied cytochrome c oxidase (COX) expression patterns in nuclear and mtDNA gene defects. Using quantitative immunocytochemical assay for COX, heteroplasmic staining was seen in MELAS patients with mtDNA mutations but similar staining variability was seen in control cell lines and nuclear gene defects. All fibroblast lines showed a wide variability in cell-to-cell COX I staining intensity. All 8 patient fibroblast lines had reduced COX staining on immunocytochemistry. In 6 lines reduced protein amount was seen on Western blotting and 7 had low COX activity. This study demonstrates that nuclear gene defects can produce a heteroplasmic appearance on immunocytochemistry.
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?-TEA-induced death receptor dependent apoptosis involves activation of acid sphingomyelinase and elevated ceramide-enriched cell surface membranes.
Cancer Cell Int.
PUBLISHED: 05-26-2010
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Alpha-tocopherol ether-linked acetic acid (?-TEA), an analog of vitamin E (RRR-alpha-tocopherol), is a potent and selective apoptosis-inducing agent for human cancer cells in vivo and in vitro. ?-TEA induces apoptosis via activation of extrinsic death receptors Fas (CD95) and DR5, JNK/p73/Noxa pathways, and suppression of anti-apoptotic mediators Akt, ERK, c-FLIP and survivin in breast, ovarian and prostate cancer cells.
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[Quantitive variation of polysaccharides content in cultivated Dendrobium candidum].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 05-11-2010
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To reveal the variation content of polysaccharides in cultivated Dendrobium candidum and the relationship between germplasms, harvesting and polysaccharides content for the breeding of quality of D. candidium.
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Reduced hydraulic permeability of three-dimensional collagen scaffolds attenuates gel contraction and promotes the growth and differentiation of mesenchymal stem cells.
Acta Biomater
PUBLISHED: 02-12-2010
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Optimal scaffold characteristics are essential for the therapeutic application of engineered tissues. Hydraulic permeability (k) affects many properties of collagen gels, such as mechanical properties, cell-scaffold interactions within three dimensions (3D), oxygen flow and nutrient diffusion. However, the cellular response to 3D gel scaffolds of defined k values has not been investigated. In this study, unconfined plastic compression under increasing load was used to produce collagen gels with increasing solid volume fractions. The Happel model was used to calculate the resulting permeability values in order to study the interaction of k with gel mechanical properties and mesenchymal stem cell (MSC)-induced gel contraction, metabolism and differentiation in both non-osteogenic (basal medium) and osteogenic medium for up to 3 weeks. Collagen gels of fibrillar densities ranging from 0.3 to >4.1 wt.% gave corresponding k values that ranged from 1.00 to 0.03 microm(2). Mechanical testing under compression showed that the collagen scaffold modulus increased with collagen fibrillar density and a decrease in k value. MSC-induced gel contraction decreased as a direct function of decreasing k value. Relative to osteogenic conditions, non-osteogenic MSC cultures exhibited a more than 2-fold increase in gel contraction. MSC metabolic activity increased similarly under both osteogenic and non-osteogenic culture conditions for all levels of plastic compression. Under osteogenic conditions MSC differentiation and mineralization, as indicated by alkaline phosphatase activity and von Kossa staining, respectively, increased in response to an elevation in collagen fibrillar density and decreased gel permeability. In this study, gel scaffolds with higher collagen fibrillar densities and corresponding lower k values provided a greater potential for MSC differentiation and appear most promising for bone grafting purposes. Thus, cell-scaffold interactions can be optimized by defining the 3D properties of collagen scaffolds through k adjustment.
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Extensive infiltration of neutrophils in the acute phase of experimental autoimmune encephalomyelitis in C57BL/6 mice.
Histochem. Cell Biol.
PUBLISHED: 01-10-2010
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To determine the possible involvement of neutrophils in the pathogenesis of experimental autoimmune encephalomyelitis (EAE), we examined their infiltration pattern during the course of MOG35-55-induced EAE in the C57BL/6 mice. Using immunohistochemistry and flow cytometry, we found that the number of neutrophils was significantly increased during onset of disease, remained high at the peak stage and dramatically declined thereafter. Moreover, dual labeling provided anatomical evidence of a prominent accumulation of neutrophils in the center and vicinity of lesion areas of demyelination, axonal loss or axonal degeneration at early stages of EAE. These observations provide evidence that neutrophils are one of the major sources of inflammatory cells to initiate EAE, which suggest that neutrophils may contribute to demyelination and axonal degeneration in the acute phase of EAE and play a greater role than previously thought in the pathogenesis of EAE.
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Crucial role of interleukin-7 in T helper type 17 survival and expansion in autoimmune disease.
Nat. Med.
PUBLISHED: 01-10-2010
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Interleukin-7 receptor (IL-7R) is genetically associated with susceptibility to multiple sclerosis. Here we describe that IL-7 is essential for survival and expansion of pathogenic T helper type 17 (T(H)17) cells in experimental autoimmune encephalomyelitis (EAE). IL-7 directly expanded effector T(H)17 cells in EAE and human T(H)17 cells from subjects with multiple sclerosis, whereas it was not required for T(H)17 differentiation. IL-7R antagonism rendered differentiated T(H)17 cells susceptible to apoptosis through the inhibition of Janus kinase-signal transducer and activator of transcription-5 (JAK-STAT5) pathway and altered expression of the prosurvival protein Bcl-2 and the proapoptotic protein Bax, leading to decreased severity of EAE. In contrast, T(H)1 and regulatory T (T(reg)) cells were less susceptible to or not affected by IL-7R antagonism in vivo. The selectivity was attributable to minimal expression of IL-7Ralpha in T(reg) cells and correlated with a high level of Socs1 (encoding suppressor of cytokine signaling-1) expression in T(H)1 cells. The study reveals a unique, previously undescribed role of IL-7-IL-7R in T(H)17 cell survival and expansion and has implications in the treatment of autoimmune disease.
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Thymic regulation of autoimmune disease by accelerated differentiation of Foxp3+ regulatory T cells through IL-7 signaling pathway.
J. Immunol.
PUBLISHED: 10-19-2009
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The exact role of adult thymus in autoimmune disease state is poorly understood. We show here that thymus regulated experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis, as evidenced by loss of spontaneous recovery in thymectomized EAE mice. There was progressive enrichment for CD4 single-positive Foxp3(+) regulatory T cells in thymocytes during the course of EAE and they suppressed the disease when adoptively transferred. Thymus was shown to undergo an active process characterized by accelerated differentiation and proliferation of regulatory T (Treg) cells through a mechanism involving increased expression of IL-7 in stromal cells and dynamic expression of IL-7 receptor in thymic Treg cells. This process preceded EAE recovery and selectively affected Treg over non-Treg cells in the thymus, leading to increased output of thymic Treg cells and self-regulation of EAE. The study reveals a novel role of thymus in self-regulation of autoimmune condition.
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One-pot synthesis of fluorescent carbon nanoribbons, nanoparticles, and graphene by the exfoliation of graphite in ionic liquids.
ACS Nano
PUBLISHED: 08-26-2009
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In this work we demonstrate a facile means to generate fluorescent carbon nanoribbons, nanoparticles, and graphene from graphite electrode using ionic liquid-assisted electrochemical exfoliation. A time-dependence study of products exfoliated from the graphite anode allows the reconstruction of the exfoliation mechanism based on the interplay of anodic oxidation and anion intercalation. We have developed strategies to control the distribution of the exfoliated products. In addition, the fluorescence of these carbon nanomaterials can be tuned from the visible to ultraviolet region by controlling the water content in the ionic liquid electrolyte.
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Structural basis for the multiple interactions of the MyD88 TIR domain in TLR4 signaling.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 06-08-2009
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Myeloid differentiating factor 88 (MyD88) and MyD88 adaptor-like (Mal) are adaptor molecules critically involved in the Toll-like receptor (TLR) 4 signaling pathway. While Mal has been proposed to serve as a membrane-sorting adaptor, MyD88 mediates signal transduction from activated TLR4 to downstream components. The Toll/Interleukin-1 receptor (TIR) domain of MyD88 is responsible for sorting and signaling via direct or indirect TIR-TIR interactions between Mal and TLR4. However, the molecular mechanisms involved in multiple interactions of the TIR domain remain unclear. The present study describes the solution structure of the MyD88 TIR domain. Reporter gene assays revealed that 3 discrete surface sites in the TIR domain of MyD88 are important for TLR4 signaling. Two of these sites were shown to mediate direct binding to the TIR domain of Mal. Interestingly, Mal-TIR, but not MyD88-TIR, directly binds to the cytosolic TIR domain of TLR4. These observations suggested that the heteromeric assembly of TIR domains of the receptor and adaptors constitutes the initial step of TLR4 intracellular signal transduction.
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Adsorption of Hg2+ from aqueous solution onto polyacrylamide/attapulgite.
J. Hazard. Mater.
PUBLISHED: 05-30-2009
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Polyacrylamide/attapulgite (PAM/ATP) was prepared by the solution polymerization of acrylamide (AM) onto gamma-methacryloxypropyl trimethoxy silane (KH-570)-modified attapulgite (ATP). PAM/ATP was characterized using Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). The effects of contact time, adsorbent dosage, and pH of the initial solution on the adsorption capacities for Hg(2+) were investigated. The adsorption process was rapid; 88% of adsorption occurred within 5 min and equilibrium was achieved at around 40 min. The equilibrium data fitted the Langmuir sorption isotherms well, and the maximum adsorption capacity of Hg(2+) onto PAM/ATP was found to be 192.5 mg g(-1). The adsorption kinetics of PAM/ATP fitted a pseudo-second-order kinetic model. Our results suggest that chemisorption processes could be the rate-limiting steps in the process of Hg(2+) adsorption. Hg(2+) adsorbed onto PAM/ATP could be effectively desorbed in hot acetic acid solution, and the adsorption capacity of the regenerated adsorbents could still be maintained at 95% by the sixth cycle.
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Human RIF1 encodes an anti-apoptotic factor required for DNA repair.
Carcinogenesis
PUBLISHED: 05-29-2009
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Human Rap1-interacting protein 1 (RIF1) contributes to the ataxia telangiectasia, mutated-mediated DNA damage response against the dexterous effect of DNA lesions and plays a critical role in the S-phase checkpoint. However, the molecular mechanisms by which human RIF1 conquers DNA aberrations remain largely unknown. We here showed that inhibition of RIF1 expression by small interfering RNA led to defective homologous recombination-mediated DNA double-strand break repair and sensitized cancer cells to camptothecin or staurosporine treatment. RIF1 underwent caspase-dependent cleavage upon apoptosis. We further found that RIF1 was highly expressed in human breast tumors, and its expression status was positively correlated with differentiation degrees of invasive ductal carcinoma of the breast. Our results suggest that RIF1 encodes an anti-apoptotic factor required for DNA repair and is a potential target for cancer treatment.
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Age-related bone loss in the LOU/c rat model of healthy ageing.
Exp. Gerontol.
PUBLISHED: 04-10-2009
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Inbred albino Louvain (LOU) rats are considered a model of healthy aging due to their increased longevity in the absence of obesity and with a low incidence of common age-related diseases. In this study, we characterized the bone phenotype of male and female LOU rats at 4, 20 and 27 months of age using quantitative micro computed tomographic (mCT) imaging, histology and biochemical analysis of circulating bone biomarkers. Bone quality and morphometry of the distal femora, assessed by mCT, was similar in male and female rats at 4 months of age and deteriorated over time. Histochemical staining of undecalcified bone showed a significant reduction in cortical and trabecular bone by 20 months of age. The reduction in mineralized tissue was accompanied by reduced numbers of osteoblasts and osteoclasts and a significant increase in marrow adiposity. Biochemical markers of bone turnover, C-telopeptide and osteocalcin, correlated with the age-related bone loss whereas the calciotropic hormones PTH and vitamin D remained unchanged over time. In summary, aged LOU rats exhibit low-turnover bone loss and marrow fat infiltration, which are the hallmarks of senile osteoporosis, and thus represent a novel model in which to study the molecular mechanisms leading to this disorder.
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A two-site, population-based study of barriers to cataract surgery in rural china.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 03-24-2009
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China has among the lowest cataract surgical rates in Asia. This study was conducted to identify barriers to cataract surgery in rural China.
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A population-based study of visual impairment among pre-school children in Beijing: the Beijing study of visual impairment in children.
Am. J. Ophthalmol.
PUBLISHED: 02-10-2009
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To evaluate the prevalence and causes of visual impairment among Chinese children aged 3 to 6 years in Beijing.
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Degenerate primers based RT-PCR for rapid detection and differentiation of airborne chicken Newcastle disease virus in chicken houses.
J. Virol. Methods
PUBLISHED: 01-13-2009
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Airborne Newcastle disease (ND) viruses in the air of five chicken houses were detected and differentiated by reverse transcriptase polymerase chain reaction (RT-PCR) using degenerate primers. Fifteen air samples were collected with All Glass Impinger-30 (AGI-30) air samplers in each house. Airborne ND viruses were also isolated and virulence identified by in vivo tests. Avirulent viruses were detected both in air samples and swab samples in four houses by degenerate primers based RT-PCR. Virulent viruses were detected only in the air samples by degenerate primers based RT-PCR in two houses. Seven strains viruses were isolated from the RT-PCR positive air samples. Of the seven strains, three strains were virulent viruses and four strains were avirulent viruses identified by in vivo tests. The results showed that it was feasible to detect and differentiate NDV in the air samples using degenerate primers based RT-PCR. This technique could decrease the time it required identify NDV infected flocks while distinguishing between virulent and avirulent viruses. It will help effectively to control Newcastle disease.
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Fluorescence quenching of 4-tert-octylphenol by room temperature ionic liquids and its application.
J Fluoresc
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The interactions between room temperature ionic liquids (RTILs) and weak fluorescent chemicals still remain unclear, which hinders the complete and efficient utilization of these "green" solvents in fluorescent analyses of organic chemicals. Herein, we reported the effects of four RTILs, [C8MIM]BF4, [C14MIM]BF4, [C8MIM]PF6 and [C14MIM]PF6, on fluorescence behavior of 4-tert-octylphenol (4-t-OP). In the fortified concentration range of 0.2-1.0 mM, the quenching effects were increased with increasing concentrations of RTILs. However, no obvious variation of peak shape of 4-t-OP was observed in the quenching process, suggesting no formation of ground-state complex between fluorophores in 4-t-OP and quencher (ionic liquids). As for anion effect, the fluorescence quenching efficiency of 4-t-OP by BF4(-) was greater than PF6(-), but the carbon chain length on the imidazolium ring had no significant relationship with fluorescence intensity of 4-t-OP. Both Ksv values (>1.0?×?10(3)?L/mol.s) and the different temperature effects demonstrated that the quenching of 4-t-OP by four RTILs was the presence of dynamic and static quenching mechanism. The FI of dansyl chloride within [C8MIM]BF4 increased nearly 5-fold as compared to the control, showing a sensitizing effect on the strong fluorescent chemicals, while a quenching effect on 4-t-OP belonging to weak fluorescent chemicals. The fluorescence-enhanced amplitude of dansyl chloride in [C8MIM]PF6 was greater than [C8MIM]BF4. The fluorescence quenching of 4-t-OP by [C8MIM]PF6 did not belong to FRET phenomenon because of no overlap of emission spectrum of 4-t-OP and absorption spectrum of [C8MIM]PF6. When 0.6 mM [C8MIM]PF6 in acetonitrile was used as the solvent, the detection limit of 4-t-OP was 3.7 ?g/L, and the linearity range was 0.01-0.8 mg/L (R(2)?=?0.9990). In summary, these results provide a theoretical foundation for the application of RTILs in weak fluorescent chemicals.
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Overexpression of a Chinese cabbage BrERF11 transcription factor enhances disease resistance to Ralstonia solanacearum in tobacco.
Plant Physiol. Biochem.
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Ethylene-responsive factors (ERFs) play diverse roles in plant growth, developmental processes and stress responses. However, the roles and underlying mechanism of ERFs remain poorly understood, especially in non-model plants. In this study, a full length cDNA of ERF gene was isolated from the cDNA library of Chinese cabbage. According to sequence alignment, we found a highly conservative AP2/ERF domain, two nuclear localization signals, and an ERF-associated Amphiphilic Repression (EAR) motif in its C-terminal region. It belonged to VIIIa group ERFs sharing the highest sequence identity with AtERF11 in all of the ERFs in Arabidopsis and designated BrERF11. BrERF11-green fluorescence protein (GFP) transient expressed in onion epidermis cells localized to the nucleus. The transcript levels of BrERF11 were induced by exogenous salicylic acid (SA), methyl jasmonate (MeJA), ethephon (ETH), and hydrogen peroxide (H(2)O(2)). Constitutive expression of BrERF11 enhanced tolerance to Ralstonia solanacearum infection in transgenic tobacco plants, which was coupled with hypersensitive response (HR), burst of H(2)O(2) and upregulation of defense-related genes including HR marker genes, SA-, JA-dependent pathogen-related genes and ET biosynthesis associated genes and downregulation of CAT1, suggesting BrERF11 may participate in pathogen-associated molecular pattern (PAMP)- and effector-triggered immunity (PTI and ETI) mediated by SA-, JA- and ET-dependent signaling mechanisms.
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Synthesis and screening of novel vitamin E derivatives for anticancer functions.
Eur J Med Chem
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?-TEA, RRR-?-tocopherol ether linked acetic acid, exhibits potent anticancer actions in vitro and in vivo; whereas, the parent molecule has no anticancer activity. In this study, we incorporated fluorine at the chroman head and/or ether linkage between the chroman head and phytyl tail of ?-TEA as well as RRR-?-tocopherol to synthesize 6 vitamin E derivatives, and evaluated the anticancer actions in vitro for ability to induce cell death by apoptosis of human MCF-7 and MDA-MB-231 breast cancer cell lines and mouse mammary cancer cell line 66cl-4GFP. All derivatives, with the exception of compound 12, exhibited anticancer properties. The modified ?-TEA ether-type phytyl group exhibited the highest pro-apoptotic activity in comparison with ?-TEA as well as other vitamin E derivatives.
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CaWRKY58, encoding a group I WRKY transcription factor of Capsicum annuum, negatively regulates resistance to Ralstonia solanacearum infection.
Mol. Plant Pathol.
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WRKY transcription factors are encoded by large gene families across the plant kingdom. So far, their biological and molecular functions in nonmodel plants, including pepper (Capsicum annuum) and other Solanaceae, remain poorly understood. Here, we report on the functional characterization of a new group I WRKY protein from pepper, termed CaWRKY58. Our data indicate that CaWRKY58 can be localized to the nucleus and can activate the transcription of the reporter ?-glucuronidase (GUS) gene driven by the 35S core promoter with two copies of the W-box in its proximal upstream region. In pepper plants infected with the bacterial pathogen Ralstonia solanacearum, CaWRKY58 transcript levels showed a biphasic response, manifested in an early/transient down-regulation and late up-regulation. CaWRKY58 transcripts were suppressed by treatment with methyl jasmonate and abscisic acid. Tobacco plants overexpressing CaWRKY58 did not show any obvious morphological phenotypes, but exhibited disease symptoms of greater severity than did wild-type plants. The enhanced susceptibility of CaWRKY58-overexpressing tobacco plants correlated with the decreased expression of hypersensitive response marker genes, as well as various defence-associated genes. Consistently, CaWRKY58 pepper plants silenced by virus-induced gene silencing (VIGS) displayed enhanced resistance to the highly virulent R.?solanacearum strain FJC100301, and this was correlated with enhanced transcripts of defence-related pepper genes. Our results suggest that CaWRKY58 acts as a transcriptional activator of negative regulators in the resistance of pepper to R.?solanacearum infection.
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Effects of ionic liquids on fluorescence characteristics of 17?- and 17?-estradiol.
J Fluoresc
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Herein, we report the effects of six different room temperature ionic liquids (RTILs) on fluorescence spectra of 17?-estradiol (EE1) and 17?-estradiol (E2). The selected RTILs belonged to the compound classes of 1-alkyl-3-methylimidazolium tetrafluoroborate ([C(n)MIM]BF(4)) and 1-alkyl-3-methyl imidazolium hexafluorophosphate ([C(n)MIM]PF(6)). RTILs had a gradual quenching effect on fluorescence intensity (FI) of EE1 and E2, and the quenching process followed the well-known Stern-Volmer theory. The quenching mechanism of EE1 and E2 by RTILs was demonstrated to be dynamic quenching. Additionally, the overall quenching efficiency by [C(n)MIM]BF(4) was higher than [C(n)MIM]PF(6). The increased carbon chain length of RTILs did not lead to obvious differences in FI for EE1 and E2. The quenching efficiency showed irregular trend at three different temperatures (25, 35 and 45 °C). RTILs such as [C(4)MIM]PF(6) had the different fluorescent effects on organic chemicals with different fluorophores. The enhancing effects of [C(4)MIM]PF(6) were observed on strong fluorescence chemicals (dansyl chloride, rhrodamine B, 1,10-phenanthroline, norfloxacin), while quenching effect on weak fluorescence chemicals (EE1 and E2). In theory, these results provide a theoretical foundation for deep insight into their interaction mechanism between RTILs and estradiol.
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Evaluation of fetal skeletal malformations in deoxynivalenol-treated mice using microarray analysis.
Arch. Environ. Contam. Toxicol.
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Deoxynivalenol (DON [vomitoxin]), one of trichothecene mycotoxins produced by the fungus Fusarium, is commonly detected in cereal foods across the world. DON induces diverse toxic effects in humans and animals, including emesis and diarrhea, anorexia, and immunotoxicity, and impaired maternal reproduction and fetal development. Recently, the teratogenic potential of DON has been shown and has received much attention. DON can cause various skeletal deformities in fetuses, but the underlying mechanisms have not yet been fully examined. In this study, fetal skeletal malformations in DON-treated maternal mice were thoroughly investigated using microarray assay. The results showed that DON administration caused various skeletal defects in fetuses, including misaligned or fused sternebrae and vertebrae, divided or fused ribs and polydactyly, hemivertebrae, short toes, and tail anomalies. Microarray analysis showed that 282 genes, including 148 downregulated and 134 upregulated genes, were abnormally expressed in fetal vertebral bones after maternal DON exposure. These identified genes can be classified into several categories: skeletal development, carcinogenesis, nervous disorders, sperm development and embryogenesis, and inflammation. Of these, 6 genes, mostly related to bone development, were intentionally selected for further validation using real-time reverse transcription-Polymerase Chain Reaction (RT-PCR). It was confirmed that the mRNA expression of 4 genes, i.e., fibrillin-1, Col9A2, 3-phosphoadenosine 5-phosphosulfate synthase 2, and Pax1, was upregulated significantly by DON administration, whereas that of 2 other genes, Runx2 and parathyroid hormone-like hormone, was downregulated significantly. Taken together, the results of our study suggest that altered expression of these 6 genes plays a critical role in fetal skeletal deformities induced by DON and thus they are worthy of further investigation.
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[Carbon-nitrogen regulation of a laccase-producing mutant of Phanerochaete chrysosporium resisting carbon and nitrogen nutritional repression].
Wei Sheng Wu Xue Bao
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Comparing the effects of different carbon-nitrogen nutrition and their consumption on laccase production, we studied the ecophysiological characteristics of Phanerochaete chrysosporium resisting nutritional repression, and the carbon-nitrogen physiological regulation mechanism of the white-rot fungi.
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Distinct roles of different forms of vitamin E in DHA-induced apoptosis in triple-negative breast cancer cells.
Mol Nutr Food Res
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Docosahexaenoic acid (DHA) has been shown to exhibit anticancer actions in vitro and in vivo in a variety of cancers. Here, we investigated the role for DHA in inducing apoptosis in triple-negative breast cancer (TNBC) and studied the mechanisms of action.
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Intracellular expression and purification of the Canstatin-N protein in Pichia pastoris.
Gene
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Canstatin-N DNA fragment amplified from human genome was inserted into the MCS of pGAP9K*, an intracellular expression vector of Pichia pastoris, to generate pGAP9K*-can-N which was then transformed into P. pastoris GS115 by electroporation. A transformant was chosen as an engineering strain from the plate containing G418 (700 ?g/ml). D-sorbitol was selected as the only carbon source. The fermentation was carried out in a 50 L bioreactor at a 20 L working volume. After 48 h fermentation with continuous feeding of 25% (w/v) D-sorbitol and 0.8% PTM4, the cell grew to A(600)=178 and intracellularly expressed Canstatin-N reached 780 mg/L. Snail enzyme was combined with water to crack P. pastoris and to release intracellular proteins. The purified recombinant Canstatin-N inhibited CAM angiogenesis and induced significant apoptosis of the human umbilical vein endothelial cell (EVC340).
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Mesenchymal stem cell transplantation to promote bone healing.
J. Orthop. Res.
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An overall decline in the availability of osteogenic precursor cells and growth factors in the bone marrow microenvironment have been associated with impaired bone formation and osteopenia in humans. The objective of the current study was to determine if transplantation of mesenchymal stromal cells (MSC) from a healthy, young donor mouse into an osteopenic recipient mouse could enhance osseointegration of a femoral implant. MSC harvested from normal young adult mice differentiated into bone forming osteoblasts when cultured on implant grade titanium surfaces ex vivo and promoted bone formation around titanium-coated rods implanted in the femoral canal of osteopenic recipient mice. Micro computed tomographic imaging and histological analyses showed more, better quality, bone in the femur that received the MSC transplant compared with the contra-lateral control femur that received carrier alone. These results provide pre-clinical evidence that MSC transplantation promotes peri-implant bone regeneration and suggest the approach could be used in a clinical setting to enhance bone regeneration and healing in patients with poor quality bone.
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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.

How does it work?

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

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

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