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Find video protocols related to scientific articles indexed in Pubmed.
A Unique 1,2-Acyl Migration for the Construction of Quaternary Carbon by Visible Light Irradiation of Platinum(II) Polypyridyl Complex and Molecular Oxygen.
Org. Lett.
PUBLISHED: 11-03-2014
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A unique 1,2-acyl migration for the construction of quaternary carbon in a one-pot reaction under visible light is described. By irradiating a platinum(II) polypyridyl complex with visible light, enamine 1 is able to react with alcohol 2 to yield compound 3 featuring a quaternary carbon via 1,2-acyl migration and concurrent esterification. Studies on the mechanism reveal that the platinum(II) complex is able to generate singlet oxygen ((1)O2) that is responsible for this unprecedented intramolecular 1,2-acyl migration transformation.
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Cisplatin and paclitaxel target significant long noncoding RNAs in laryngeal squamous cell carcinoma.
Med. Oncol.
PUBLISHED: 09-01-2014
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The objectives of this study were to identify specific long noncoding RNAs (lncRNAs) in laryngeal squamous cell carcinoma (LSCC) and to clarify the function of cisplatin and paclitaxel on the confirmed laryngeal cancer lncRNAs. Fifty-four pairs of laryngeal tumor and adjacent normal tissue were collected. Candidate lncRNAs were searched in authorized databases. The significant lncRNAs were identified and confirmed through high-output real-time PCR. Chemotherapy assay evaluated the influences of cisplatin and paclitaxel on the significant lncRNAs. Thirty-seven cancer-related candidate lncRNAs were selected. Three up-expressed and two down-expressed significant lncRNAs were identified and confirmed. The expressions of lncRNA CDKN2B-AS1, HOTAIR and MALAT1 were dramatically reduced with the increasing concentration of cisplatin and paclitaxel and also lengthening of the treatment duration. Cisplatin and paclitaxel have target function on significant lncRNAs in LSCC, which presents novel molecular targets to cure LSCC patients and also leads an orientation for developing new drugs.
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[Study on transition metals in airborne particulate matter in Shanghai city's subway].
Huan Jing Ke Xue
PUBLISHED: 08-28-2014
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PM10 and PM2.5 aerosol particle samples were collected at a subway station in Shanghai and their morphology, chemical composition and transition metal species were studied. The mass concentrations of PM10 and PM2.5 inside the subway station were significantly higher than those measured in aboveground ambient air. The PM levels inside subway were much higher than the state control limit. The aerosol composition in the metro station was quite different from that of the aboveground urban particles. Concentrations of Fe, Mn and Cr were higher than the averages of aboveground urban air particles by factors of 8, 2, and 2, respectively, showing a substantial enrichment in subway. Scanning electron microscope (SEM) analysis showed that the subway particles had flat surfaces in combination with parallel scratches and sharp edges and looked like metal sheets or flakes. Furthermore, analysis of the atomic composition of typical subway particles by energy dispersive X-Ray (EDX) spectroscopy showed that oxygen and iron dominated the mass of the particles. The X-ray absorption near-edge structure (XANES) spectroscopy results showed that a fraction (> 26%) of the total iron in the PM10 was in the form of pure Fe, while in the street particles Fe(III) was shown to be a significant fraction of the total iron. The work demonstrated that the underground subway stations in Shanghai were an important microenvironment for exposure to transition metal aerosol for the people taking subway train for commuting every day and those who work in the subway stations, and the metal particle exposure for people in the subway station should not be ignored.
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Effect of activator on the structure and desulphurization efficiency of sludge-activated carbon.
Environ Technol
PUBLISHED: 08-23-2014
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Sludge-activated carbons (SACs) prepared with excess of activated sludge are used to solve the problems of sludge disposal and odour pollution in a sewage treatment plant. For the preparation, ZnCl2, KOH and H2SO4 are used as activators, respectively. The structure of the SACs are characterized by scanning electron microscope, X-ray photoelectron spectrometer, specific surface area and pore structure technologies, and the adsorption performance of H2S is investigated. Results indicate that the desulphurization activity of SACs, whose activators are ZnCl2 and KOH (SACZ and SACK), is better than that of carbon with H2SO4 as the activator (SACH). The breakthrough time of SACZ and SACK is up to 86 min, the sulphur capacity is 7.7 mg/cm3, and the maximal iodine value is 409.95 mg/g. While the breakthrough time of SACH is only 26 min with the sulphur capacity of 2.3 mg/cm3. A large percentage of pore volume with a diameter of 2-5 nm in the total pore volume is conductive to the desulphurization reaction. The large amount of surface acid functional groups is also helpful to the adsorption of H2S. The desulphurization activity of SACZ and SACK is superior over that of commercial-activated carbon.
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Expression, purification, and characterization of recombinant mouse nerve growth factor in Chinese hamster ovary cells.
Protein Expr. Purif.
PUBLISHED: 08-21-2014
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Mouse NGF (mNGF) extracted from mouse submaxillary gland has been approved on the market in China for treating nerve damage caused by N-hexane poisoning for over a decade, and many researches showed the clinical effectiveness of mNGF for the treatment of other nerve system diseases. The extracted mNGF have risks of potential viral contamination due to the animal origin. Here, we report the successful expression, purification, and characterization of recombinant mNGF (rmNGF). An expression plasmid of mouse nerve growth factor (mNGF) was constructed and transfected into CHO-S cells. Stable transfectants were obtained using a two-phase selection scheme with the addition of different concentrations of methotrexate and puromycin. Recombinant mNGF (rmNGF) was purified from cell culture medium by a two-step procedure: cation exchange followed by size-exclusion chromatography. The purity of rmNGF was 98.6% determined by size exclusion high performance liquid chromatography (SEC-HPLC). The molecular weight, isoelectric point and N-terminal sequence of rmNGF were identical to the theoretical values entirely. In TF-1/MTS, the specific activity of the protein was approximately 1.7×10(6)U/mg against rhNGF (the reference standard). In DRGs, the specific activity was approximately 7.3×10(5)AU/mg against mNGF (the reference standard). Our results showed that a high quality of rmNGF with marked biological activity comparable with mNGF was produced, and laid the basis for further research and development of rmNGF.
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Gastroesophageal reflux and carcinoma of larynx or pharynx: a meta-analysis.
Acta Otolaryngol.
PUBLISHED: 08-18-2014
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The meta-analysis supported the proposition that the prevalence of gastroesophageal reflux disease (GERD) was associated with laryngeal cancer, particularly in the hospital-based control group and diagnosed by esophagogastroduodenoscopy (EGD) or esophageal pH monitoring. However, no significant association was found between GERD and pharyngeal carcinoma.
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Temperature-programmed technique accompanied with high-throughput methodology for rapidly searching the optimal operating temperature of MOX gas sensors.
ACS Comb Sci
PUBLISHED: 08-12-2014
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A combinatorial high-throughput temperature-programmed method to obtain the optimal operating temperature (OOT) of gas sensor materials is demonstrated here for the first time. A material library consisting of SnO2, ZnO, WO3, and In2O3 sensor films was fabricated by screen printing. Temperature-dependent conductivity curves were obtained by scanning this gas sensor library from 300 to 700 K in different atmospheres (dry air, formaldehyde, carbon monoxide, nitrogen dioxide, toluene and ammonia), giving the OOT of each sensor formulation as a function of the carrier and analyte gases. A comparative study of the temperature-programmed method and a conventional method showed good agreement in measured OOT.
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Comparison of two anterior fusion methods in two-level cervical spondylosis myelopathy: a meta-analysis.
BMJ Open
PUBLISHED: 07-18-2014
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The aim of this study was to evaluate the efficacy and safety of anterior cervical corpectomy and fusion (ACCF) and anterior cervical discectomy and fusion (ACDF) for treating two-adjacent-level cervical spondylosis myelopathy (CSM).
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Hapten synthesis and development of a competitive indirect enzyme-linked immunosorbent assay for acrylamide in food samples.
J. Agric. Food Chem.
PUBLISHED: 07-10-2014
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The high level of acrylamide in widely consumed processed foods poses a potentially significant risk to human health, which has led to an increasing demand for rapid, simple, and selective analytical methods. In the present work, several haptens for acrylamide were designed in an attempt to prepare antibodies with acrylamide affinity, but they failed their purpose. However, a polyclonal antibody was produced against 4-mercaptophenylacetic acid (4-MPA)-derivatized acrylamide, which showed high binding affinity to the derivative. As acrylamide easily reacted with 4-MPA at high derivation yield, a competitive indirect enzyme-linked immunosorbent assay (ciELISA) for acrylamide via a preanalysis derivatization was developed. The derivatization and ELISA conditions were fully optimized to produce a method for acrylamide assay that exhibited an IC50 of 2.86 ?g/kg, limit of detection at 0.036 ?g/kg, and linear range of 0.25-24.15 ?g/kg. The results of preanalysis recovery tests of acrylamide-spiked food samples and screening of blind food samples by both ciELISA and HPLC-MS/MS indicated the proposed ciELISA's good accuracy and reliability. This method was thus deemed suitable for routine acrylamide screening in food samples at low cost.
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The complete mitochondrial genome of Diqing wild boar (Sus verrucosus breed Diqing wild boar).
Mitochondrial DNA
PUBLISHED: 06-28-2014
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Abstract In the present study, the complete mitochondrial genome sequence of the diqing wild boar (Sus verrucosus breed diqing wild boar) was reported for the first time. The total length of the mitogenome was 16,506?bp. It contained the typical structure, including two ribosomal RNA genes, 13 protein-coding genes, 22 transfer RNA genes and one non-coding control region (D-loop region) as that of most other wild boars. The overall composition of the mitogenome was estimated to be 34.9% for A, 26.1% for T, 26.0% for C and 13.0% for G showing an A-T (61.0%)-rich feature. The mitochondrial genome analyzed here will provide new genetic resource to uncover wild boars' genetic diversity.
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Anterior longitudinal decompression in the management of severe ossification of the posterior longitudinal ligament in the cervical spine.
Orthopedics
PUBLISHED: 05-10-2014
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The advantages of anterior surgery for severe ossification of the posterior longitudinal ligament in the cervical spine have been reported. However, it is more technically demanding and associated with a high risk of surgery-related complications. The purpose of this study was to evaluate the feasibility of longitudinal decompression techniques in anterior surgery for severe ossification of the posterior longitudinal ligament in the cervical spine. Between June 2008 and December 2011, twenty-two patients (16 men and 6 women; average age, 58 years [range, 45-72 years]) who underwent anterior corpectomy and fusion for severe ossification of the posterior longitudinal ligament were studied retrospectively. The clinical efficacy, canal narrowing ratio, fused segment height, and complications were investigated. After a mean 25.4-month follow-up, mean Japanese Orthopaedic Association score increased from 8.8±1.4 preoperatively to 14.0±1.2 at final follow-up (P<.05), an improvement rate of 63.5%±12.5%. Mean canal narrowing ratio decreased from 62.0%±6.0% preoperatively to 8.2%±4.9% postoperatively (P<.05). Mean fused segment height increased 2.3±0.5 mm from pre- to postoperatively and decreased 2.8±0.4 mm from postoperatively to final follow-up (P>.05). Five patients developed cerebrospinal fluid leakage, and 1 patient experienced hematoma. No instrument failure was observed, and all patients had successful fusion. Anterior longitudinal decompression is a relatively effective procedure in the management of severe ossification of the posterior longitudinal ligament in the cervical spine. It can be applied to treat closed-base ossification of the posterior longitudinal ligament (defined as no space between the lateral margin of the ossified base and the spinal canal lateral wall), but it is associated with a high risk of cerebrospinal fluid leakage.
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Evidence for Preoperative Aspirin Improving Major Outcomes in Patients With Chronic Kidney Disease Undergoing Cardiac Surgery: A Cohort Study.
Ann. Surg.
PUBLISHED: 04-19-2014
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Effects of aspirin on patients with chronic kidney disease (CKD) remains unclear. This study aimed to examine the effect of preoperative aspirin use on postoperative renal function and 30-day mortality in patients with CKD undergoing cardiac surgery.
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The effect of Lfcin-B on non-small cell lung cancer H460 cells is mediated by inhibiting VEGF expression and inducing apoptosis.
Arch. Pharm. Res.
PUBLISHED: 03-15-2014
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Lfcin-B, an antimicrobial peptide found in various exocrine secretions of mammals, showed antitumor effects. However, the effect and relative mechanism of Lfcin-B on non-small cell lung cancer is unclear. In this study, assay of cell viability, quantitative real-time PCR, Western blot, annexin V/propidium iodide assay, flow cytometry and tumor-xenograft model were applied to elucidate the mechanism of Lfcin-B on non-small cell lung cancer NCI-H460 (H460) cells. Lfcin-B significantly suppressed the proliferation of H460 cells in vitro. Additionally, the transcription and translation of the VEGF gene in H460 cells were restrained after exposure to Lfcin-B. Moreover, the apoptosis of H460 cells was induced by Lfcin-B through stimulating caspase-3, caspase-9 and preventing survivin expression on both the transcription and translation level. Meanwhile, Lfcin-B increased the production of reactive oxygen species and suppressed the RNA of antioxidant enzymes (GPX1, GPX2, SOD3 and catalase) in H460 cells. Finally, Lfcin-B significantly prevented the tumor growth in the H460-bearing mice model. These results indicated that Lfcin-B could be a potential candidate for the treatment of lung cancer.
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Cross-coupling hydrogen evolution reaction in homogeneous solution without noble metals.
Org. Lett.
PUBLISHED: 03-14-2014
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A highly efficient noble-metal-free homogeneous system for a cross-coupling hydrogen evolution (CCHE) reaction is developed. With cheap, earth-abundant eosin Y and molecular catalyst Co(dmgH)2Cl2, good to excellent yields for coupling reactions with a variety of isoquinolines and indole substrates and H2 have been achieved without any sacrificial oxidants. Mechanistic insights provide rich information on the effective, clean, and economic CCHE reaction.
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On-road ammonia emissions characterized by mobile, open-path measurements.
Environ. Sci. Technol.
PUBLISHED: 03-10-2014
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Ammonia (NH3) is a key precursor species to atmospheric fine particulate matter with strong implications for regional air quality and global climate change. NH3 from vehicles accounts for a significant fraction of total emissions of NH3 in urban areas. A mobile platform is developed to measure NH3, CO, and CO2 from the top of a passenger car. The mobile platform conducted 87 h of on-road measurements, covering 4500 km in New Jersey and California. The average on-road emission factor (EF) in CA is 0.49 ± 0.06 g NH3 per kg fuel and agrees with previous studies in CA (0.3-0.8 g/kg). The mean on-road NH3:CO emission ratio is 0.029 ± 0.005, and there is no systematic difference between NJ and CA. On-road NH3 EFs increase with road gradient by an enhancement of 53 mg/kg fuel per percentage of gradient. On-road NH3 EFs show higher values in both stop-and-go driving conditions and freeway speeds with a minimum near 70 km/h. Consistent with prior studies, the on-road emission ratios suggest a highly skewed distribution of NH3 emitters. Comparisons with existing NJ and CA on-road emission inventories indicate that there may be an underestimation of on-road NH3 emissions in both NJ and CA. We demonstrate that mobile, open-path measurements provide a unique tool to help quantitatively understand the on-road NH3 emissions in urban and suburban settings.
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The upstream conserved regions (UCRs) mediate homo- and hetero-oligomerization of type 4 cyclic nucleotide phosphodiesterases (PDE4s).
Biochem. J.
PUBLISHED: 02-22-2014
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PDE4s (type 4 cyclic nucleotide phosphodiesterases) are divided into long and short forms by the presence or absence of conserved N-terminal domains termed UCRs (upstream conserved regions). We have shown previously that PDE4D2, a short variant, is a monomer, whereas PDE4D3, a long variant, is a dimer. In the present study, we have determined the apparent molecular masses of various long and short PDE4 variants by size-exclusion chromatography and sucrose density-gradient centrifugation. Our results indicate that dimerization is a conserved property of all long PDE4 forms, whereas short forms are monomers. Dimerization is mediated by the UCR domains. Given their high sequence conservation, the UCR domains mediate not only homo-oligomerization, but also hetero-oligomerization of distinct PDE4 long forms as detected by co-immunoprecipitation assays and FRET microscopy. Endogenous PDE4 hetero-oligomers are, however, low in abundance compared with homo-dimers, revealing the presence of mechanisms that predispose PDE4s towards homo-oligomerization. Oligomerization is a prerequisite for the regulatory properties of the PDE4 long forms, such as their PKA (protein kinase A)-dependent activation, but is not necessary for PDE4 protein-protein interactions. As a result, individual PDE4 protomers may independently mediate protein-protein interactions, providing a mechanism whereby PDE4s contribute to the assembly of macromolecular signalling complexes.
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Trends in Specific Immunotherapy for Allergic Rhinitis: A Survey of Chinese ENT Specialists.
Allergy Asthma Immunol Res
PUBLISHED: 02-13-2014
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Specific immunotherapy (SIT) is a suitable but uncommon treatment option for allergic rhinitis (AR) in China. The current understanding and attitude of Chinese ENT (ear, nose, and throat) specialists in regards to SIT is unclear. This study investigates current trends in the awareness and application status of SIT among Chinese ENT specialists.
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Association of interleukin-10 promoter polymorphisms and corresponding plasma levels with susceptibility to laryngeal squamous cell carcinoma.
Oncol Lett
PUBLISHED: 02-07-2014
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Interleukin (IL)-10 is critically involved in tumorigenesis. In the present study, the association between the IL-10 -1082/-819/-592 promoter polymorphisms, the plasma IL-10 levels and the risk of laryngeal squamous cell carcinoma (LSCC) was investigated in a prospective, case-control study. In total, 146 patients with LSCC, 61 with vocal leukoplakia and 119 healthy controls were genotyped for the IL-10 gene (IL-10 -1082 A/G, -819 T/C and -592 A/C) using pyrosequencing, and their plasma IL-10 levels were analyzed by ELISA. The patients with LSCC had a significantly higher frequency of AC at position -592 and -819 (OR, 1.82 and P=0.024) compared with the control, and a higher frequency of AG at position -1082 (OR, 2.20 and P=0.037). The patients with advanced LSCC had a significantly higher frequency of AG+GG at position -1082 compared with those with early-stage LSCC (OR, 3.13 and P=0.008 vs. OR, 2.06 and P=0.068). The patients with lymph node metastasis had a significantly higher frequency of AG+GG at position -1082 compared with the patients with no lymph node metastasis (OR, 2.97 and P=0.048 vs. OR, 2.23 and P=0.035). In addition, the patients with high frequencies of each genotype polymorphism had high plasma IL-10 concentrations. The present study indicates that the IL-10 -1082/-819/-592 promoter polymorphisms and corresponding high plasma IL-10 concentrations are associated with LSCC, and that variations in genotype distribution and plasma IL-10 concentrations may be associated with the stage and the lymph node metastasis status of LSCC.
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Effect of mouse oocyte vitrification on mitochondrial membrane potential and distribution.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 02-06-2014
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The effects of mouse oocyte vitrification on mitochondrial membrane potential and distribution were explored in this study. The collected mouse oocytes were randomly divided into vitrification and control groups. Ethylene glycol (EG) and dimethylsulphoxide (DMSO) were used as cryoprotectants in the vitrification group. The mitochondrial function and distribution in the oocytes were examined by using the fluorescent probes, JC-1 and Mito Tracker green. The results showed that the ratio of red to green fluorescence in mouse oocytes was significantly decreased after thawing in the vitrification group as compared with the control group (1.28 vs. 1.70, P<0.05). The percentage of polarized distribution of the mitochondria in oocytes was conspicuously reduced in the vitrification group when compared with the control group (31% vs. 63%, P<0.05). It was suggested that vitrification significantly affects the mitochondrial function and distribution in oocytes and reduces the potential of oocyte fertilization and embryo development.
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Low concentrations of trichosanthin induce apoptosis and cell cycle arrest via c?Jun N?terminal protein kinase/mitogen?activated protein kinase activation.
Mol Med Rep
PUBLISHED: 02-03-2014
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Trichosanthin (TCS) is a type I ribosome?-inactivating protein, which inhibits cell viability in human epithelial type 2 (HEp?2) and AMC?HN?8 human laryngeal epidermoid carcinoma cells. Although TCS is a potential chemotherapeutic agent, its mechanism of action remains to be elucidated. In the present study, HEp?2 and AMC?HN?8 cells were treated with different concentrations of TCS combined with or without cisplatin. After 5 days of successive treatment, different experimental groups were detected using a cell counting kit?8 and the collected supernatants were analyzed using a lactate dehydrogenase kit. Flow cytometric assays were performed to detect apoptosis and cell cycle arrest in the HEp?2 and AMC?HN?8 cells, reverse transcription quantitative polymerase chain reaction was performed to detect the levels of p27, p21WAF and western blot analysis was performed to detect changes in c?Jun N?terminal protein kinase (JNK)/phosphorylated (phospho)?JNK, p38/phospho?p38, extracellular signal?regulated kinase (ERK)/phospho?ERK, caspase?3 and caspase?9 in the HEp?2 and AMC?HN?8 cancer cells. TCS significantly inhibited the cell viability of the HEp?2 and AMC?HN?8 cells, independently of necrosis. TCS induced apoptosis and increased the percentage of HEp?2 and AMC?HN?8 cells in the S?phase of the cell cycle. In addition, the JNK/mitogen?activated protein kinase (MAPK) pathway was activated by TCS in the HEp?2 and AMC?HN?8 cells. Low concentrations of TCS also induced apoptosis and S?phase cell cycle arrest in the HEp?2 and AMC?HN?8 cells. The antitumor effects of TCS may be associated with JNK/MAPK activation.
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Hypoxia promotes stem-like properties of laryngeal cancer cell lines by increasing the CD133+ stem cell fraction.
Int. J. Oncol.
PUBLISHED: 01-30-2014
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Evidence indicates that a hypoxic micro-environment plays an essential role in the regulation of cancer stem cells (CSCs). However, whether hypoxia is able to regulate the stem-like biological properties of laryngeal cancer cells remains unknown. In this study, we investigated the influence of hypoxia on the stemness of two laryngeal cancer cell lines, Hep-2 and AMC-HN-8. We cultured the two cell lines under hypoxia and normoxia and examined the influence of hypoxia on the expression of hypoxia-inducible factors (HIFs) and the cancer stem-like properties of these cells, including cell cycle distribution, expression of stem cell genes (OCT4, SOX2 and NANOG) and laryngeal CSC surface marker (CD133), proliferation, invasion, colony formation and sphere formation capacity. We determined that both of these cell lines, when maintained under hypoxic conditions, showed expanded cells in the G0/G1 phase, exhibited preferential expression of stem cell genes and CD133, and manifested upregulation of HIFs. When treated with hypoxia followed by normoxia exposure, the two cell lines exhibited enhanced capacities for proliferation, invasion, and sphere and colony formation compared with cells maintained consistently under normoxia. Our findings indicate that a hypoxic microenvironment may upgrade the stem-like biological properties of laryngeal cancer cell lines by the expansion of the CD133(+) stem cell fraction.
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Polysaccharides from Angelica sinensis alleviate neuronal cell injury caused by oxidative stress.
Neural Regen Res
PUBLISHED: 01-20-2014
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Angelica sinensis has antioxidative and neuroprotective effects. In the present study, we aimed to determine the neuroprotective effect of polysaccharides isolated from Angelica sinensis. In a preliminary experiment, Angelica sinensis polysaccharides not only protected PC12 neuronal cells from H2O2-induced cytotoxicity, but also reduced apoptosis and intracellular reactive oxygen species levels, and increased the mitochondrial membrane potential induced by H2O2 treatment. In a rat model of local cerebral ischemia, we further demonstrated that Angelica sinensis polysaccharides enhanced the antioxidant activity in cerebral cortical neurons, increased the number of microvessels, and improved blood flow after ischemia. Our findings highlight the protective role of polysaccharides isolated from Angelica sinensis against nerve cell injury and impairment caused by oxidative stress.
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Association between the g.14461A>G genetic polymorphism of the TLR4 gene and type 2 diabetes mellitus risk in a Chinese population.
Genet Test Mol Biomarkers
PUBLISHED: 01-20-2014
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Toll-like receptor 4 (TLR4) is an important candidate gene for mediating the susceptibility to type 2 diabetes mellitus (T2DM). The purpose of this study was to investigate the association between the TLR4 gene polymorphisms and T2DM susceptibility.
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Thermo and pH dual-responsive materials for controllable oil/water separation.
ACS Appl Mater Interfaces
PUBLISHED: 01-16-2014
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Thermo and pH dual-controllable oil/water separation materials are successfully fabricated by photo initiated free radical polymerization of dimethylamino ethyl methacrylate (DMAEMA). The PDMAEMA hydrogel coated mesh shows superhydrophilicity and underwater superoleophobicity at certain temperature and pH. Due to the double responsiveness of PDMAEMA hydrogel, the as-prepared mesh can selectively separate water from oil/water mixtures and make water and oil permeate through the mesh orderly and be collected separately by adjusting the temperature or pH. Water can pass through the as-prepared mesh under 55 °C (pH 7) and pH less than 13 (T = 25 °C) while oil is kept on the mesh. When the temperature is above 55 °C or pH is larger than 13, the water retention capacity of PDMAEMA hydrogel is significantly reduced and the swelling volume is decreased. Therefore, oil can permeate through the mesh and be collected in situ. Additionally, this material has excellent potential to be used in practical applications and has created a new field for water/oil separation in which the process can be diversified and more intelligent.
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Injury to the endothelial surface layer induces glomerular hyperfiltration rats with early-stage diabetes.
J Diabetes Res
PUBLISHED: 01-14-2014
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Glomerular endothelial surface layer (ESL) may play a role in the mechanisms of albuminuria in diabetic nephropathy, which lack evidence in vivo. The effects of high glucose on the passage of albumin across the glomerular ESL were analysed in streptozotocin-induced diabetic Sprague-Dawley rats for 4 weeks. Albuminuria and glomerular mesangial matrix were significantly increased in diabetic rats. The passage of albumin across the ESL, as measured by albumin-colloid gold particle density in the glomerular basement membrane (GBM), was increased significantly in diabetic rats. The thickness of the glomerular ESL, examined indirectly by infusing Intralipid into vessels using an electron microscope, was significantly decreased and the GBM exhibited little change in diabetic rats. In summary, the glomerular ESL may play a role in the pathogenesis of albuminuria in rats with early-stage diabetes.
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Rapid immunochromatographic assay for ofloxacin in animal original foodstuffs using native antisera labeled by colloidal gold.
Talanta
PUBLISHED: 01-10-2014
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An immunochromatographic assay was developed to detect fluoroquinolone antibiotic ofloxacin based on the competitive binding of ofloxacin and the membrane-immobilized ofloxacin-protein conjugate to colloidal gold-labeled antibodies in the course of the labeled antibodies, and to test sample flow through the membrane. The specific feature of labeling by colloidal gold is that native antiserum is used instead of purified immunoglobulins or specific antibodies. This makes the synthetic procedure easier, with no sacrifice in the detection limit. The proposed test makes it possible to detect down to 30 ng mL(-1) of ofloxacin, which corresponds to the demands of food safety assessment. The assay time is 10 min. The assay provides reliable information on the ofloxacin content in milk without the sample preparation and in chicken and pork meat with the minimum sample preparation (the separation of the insoluble fraction of the homogenate by centrifugation). The high degree of detection of ofloxacin in foodstuffs by the proposed assay (70-112%) was shown by a comparison with the data obtained with the use of a commercial immunoenzymatic kit.
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LL-202, a newly synthesized flavonoid, inhibits tumor growth via inducing G(2)/M phase arrest and cell apoptosis in MCF-7 human breast cancer cells in vitro and in vivo.
Toxicol. Lett.
PUBLISHED: 01-07-2014
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We recently established that LL-202, a newly synthesized flavonoid, exhibited obvious anticancer effects against human breast cells in vivo and in vitro. The underlying mechanism of its anticancer activity remains to be elucidated. In this study, we demonstrated that LL-202 inhibited the growth and proliferation of human breast cancer MCF-7 cells in a concentration and time-dependent manner. We reported that LL-202 induced both mitochondrial- and death-receptor-mediated apoptosis, which were characterized by the dissipation of mitochondrial membrane potential (??m), cytochrome c (Cyt c) release from mitochondria to cytosol, the activation of several caspases and induction of poly (ADP-ribose) polymerase (PARP) and Bid cleavage. N-acetylcysteine (NAC), a general ROS scavenger, partly blocked the LL-202-induced ROS levels and apoptosis. In addition, LL-202 induced arrest in cell cycle progression at G2/M phase in MCF-7 cells. After the treatment with LL-202, the expression of cell cycle-related proteins, such as cyclin B1, cyclin A, and p-CDK1 (Thr161) were down-regulated, whereas the expression of p21(WAF1/Cip1) and p-CDK1 (Thr14/Tyr15) were up-regulated. Finally, in vivo studies, LL-202 significantly suppressed the growth of MCF-7 breast cancer xenograft tumors in a dose-dependent manner with low systemic toxicity. In conclusion, the results showed that LL-202 had significant anticancer effects against human breast cells via the induction of apoptosis and G2/M phase arrest and it may be a novel anticancer agent for treatment of breast cancer.
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Expression of monocyte chemotactic protein-1/CCL2 in gastric cancer and its relationship with tumor hypoxia.
World J. Gastroenterol.
PUBLISHED: 01-04-2014
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To investigate the expression and prognostic value of CCL2 in gastric cancer, as well as its relationship with tumor hypoxia.
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A Nuclear Factor of High Mobility Group Box Protein in Toxoplasma gondii.
PLoS ONE
PUBLISHED: 01-01-2014
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High mobility group box 1 (HMGB1) is a nuclear factor that usually binds DNA and modulates gene expression in multicellular organisms. Three HMGB1 orthologs were predicted in the genome of Toxoplasma gondii, an obligate intracellular protozoan pathogen, termed TgHMGB1a, b and c. Phylogenetic and bioinformatic analyses indicated that these proteins all contain a single HMG box and which shared in three genotypes. We cloned TgHMGB1a, a 33.9 kDa protein that can stimulates macrophages to release TNF-?, and, we demonstrated that the TgHMGB1a binds distorted DNA structures such as cruciform DNA in electrophoretic mobility shift assays (EMSA). Immunofluorescence assay indicated TgHMGB1a concentrated in the nucleus of intracellular tachyzoites but translocated into the cytoplasm while the parasites release to extracellular. There were no significant phenotypic changes when the TgHMGB1a B box was deleted, while transgenic parasites that overexpressed TgHMGB1a showed slower intracellular growth and caused delayed death in mouse, further quantitative RT-PCR analyses showed that the expression levels of many important genes, including virulence factors, increased when TgHMGB1a was overexpressed, but no significant changes were observed in TgHMGB1a B box-deficient parasites. Our findings demonstrated that TgHMGB1a is indeed a nuclear protein that maintains HMG box architectural functions and is a potential proinflammatory factor during the T.gondii infection. Further studies that clarify the functions of TgHMGB1s will increase our knowledge of transcriptional regulation and parasite virulence, and might provide new insight into host-parasite interactions for T. gondii infection.
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Protective effects of bifidobacterial adhesin on intestinal mucosa of stressed male rats via modulation of inflammation.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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This study aimed to assess BA impact on inflammation markers and repair of intestinal mucosa. Forty-eight rats were randomly divided into stress (n = 24) and BA (n = 24) groups. Stress was induced by fettering in all animals, fed enterally with 125.4 kJ/kg/d and 0.2 g/kg/d nitrogen. Then, rats were treated for 8 days with 5 mg/kg/d BA (BA group) or 5 mg/kg/d saline (Stress group). Levels of NF-?B, IL-10, TNF-?, and IFN-? were measured at different time points, in plasma and intestinal mucosa samples. Changes in intestinal mucosa morphology were observed by electron microscopy. Plasma and/or mucosal levels of NF-?B, TNF-?, and IFN-? were significantly higher in both groups after stress induction (P < 0.05). These high levels persisted in control animals throughout the experiment, and were significantly reduced in the BA group, 3 and 8 days after stress induction (P < 0.05). Interestingly, IL-10 levels were increased after BA treatment (P < 0.05). At day 8, ileal mucosal villi and crypt structure were significantly restored in the BA group. Bifidobacterial adhesin plays a role in repairing intestinal mucosa injury after stress by regulating the release of inflammatory mediators in the intestinal mucosa.
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ROP18 is a key factor responsible for virulence difference between Toxoplasma gondii and Neospora caninum.
PLoS ONE
PUBLISHED: 01-01-2014
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Toxoplasma gondii (T. gondii) and Neospora caninum (N. caninum) are both obligate intracellular protozoan parasites and share many common morphological and biological features. Despite these similarities the two parasites differ dramatically in virulence in mice, but the factors involved in virulence differences between the two parasites remain unknown. A secreted serine-threonine kinase called rhoptry protein 18 (ROP18) was identified to play a crucial role on virulence differences among different T. gondii clonal lineages. Intriguingly, we found that ROP18 in Nc1 strain of N. caninum (NcROP18) is a pseudogene due to several interrupting stop codons in the sequence in our previous studies. We assume that the difference of ROP18 leads to virulence difference between T. gondii and N. caninum. We constructed a transgenic N. caninum Nc1 stain by transfecting the TgROP18 from the T. gondii RH strain. Phenotype and virulence assays showed that the expression of TgROP18 in N. caninum did not affect the motility and cell invasion, but resulted in a significant increase in intracellular parasite proliferation and virulence in mice. Immunity-Related GTPase (IRG) phosphorylation assay showed that the transgenic parasite Nc1-TgROP18 was able to phosphorylate IRGs as T. gondii did. The present study indicated that the ROP18 plays a crucial role in virulence of the closely related parasites T. gondii and N. caninum and it is indeed a key factor responsible for the virulence difference between T. gondii and N. caninum.
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Vitrification of in vitro matured oocytes: effects on meiotic spindle configuration and mitochondrial function.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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In the assisted reproductive technique, cryopreserving in vitro-matured oocytes is a new strategy to extend the pool of total oocytes. However, oocyte cryopreservation technique is still unsatisfied. So the assessment of cyro-damage on meiotic spindle and mitochondrial function is necessary to evaluate and refine the current protocols.
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Changed trends of major causes of visual impairment in Sichuan, China from 1987 to 2006.
Int J Ophthalmol
PUBLISHED: 01-01-2014
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To study the trends of major causes of visual impairment (VI) in adults in Sichuan, China and evaluate the effect of aging on the trends.
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Significance of MDM2-309 Polymorphisms and Induced Corresponding Plasma MDM2 Levels in Susceptibility to Laryngeal Squamous Cell Carcinoma.
DNA Cell Biol.
PUBLISHED: 12-10-2013
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The tumor suppressor p53 plays a crucial role in maintaining genomic stability and tumor prevention. Murine double-minute 2 (MDM2) oncoprotein plays a pivotal role in regulating p53, and the single-nucleotide polymorphism (SNP) 309T/G SNP in the promoter region of Mdm2 has been shown to be associated with increased risk of cancer. We investigated the association between Mdm2-309 promoter polymorphism, plasma MDM2 levels, and risk of laryngeal squamous cell carcinoma (LSCC). In this case-control study, 146 patients with LSCC, 61 patients with vocal leukoplakia, and 212 healthy controls were genotyped for the Mdm2-309 T/G gene using pyrosequencing. Plasma MDM2 levels were also analyzed by enzyme-linked immunosorbent assay (ELISA). Patients with LSCC had a significantly lower frequency of GT at Mdm2-309 (odds ratio [OR]=0.50, p=0.02) than controls. The proportion of GT heterozygotes in advanced stage cases were less than that in the initial stage patients (OR: 0.36 vs. 0.63; p=0.007 and 0.16). The same result was found between cases with and without lymph node metastases (OR: 0.45 vs. 0.52; p=0.075 and 0.04). Moreover, the plasma Mdm2 concentrations of LSCC patients (343.36±14.8?pg/mL) were significantly higher than those in controls (255.76±8.2?pg/mL; p<0.01) and vocal leukoplakia patients (301.42±8.6?pg/mL; p<0.05). Patients in advanced stages and with lymph node metastasis had higher plasma MDM2 levels, while the GT genotypes (308.06±18.9?pg/mL; p=0.037) had lower MDM2 plasma levels than the TT genotypes (369.00±25.2?pg/mL). The Mdm2 SNP309 G allele is implicated as an important LSCC and a vocal leukoplakia protective factor in the Chinese Han Population, and the proportion of GT genotype was lower in advanced LSCC patients and lymph node metastasis patients. Moreover, Mdm2-309 GT genotype patients had a lower plasma MDM2 level than the TT genotypes.
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Bio-Inspired Anti-Oil-Fouling Chitosan-Coated Mesh for Oil/Water Separation Suitable for Broad pH Range and Hyper-Saline Environments.
ACS Appl Mater Interfaces
PUBLISHED: 11-11-2013
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Here, we report a bio-inspired chitosan (CS)-based mesh with high separation efficiency, oil-fouling repellency, and stability in a complex liquid environment. The surface of the CS coating maintains underwater superoleophobicity and low oil adhesion (<1 ?N) in pure water and hyper-saline solutions, and it can keep stable special wettability in broad pH range environments after the CS mesh is fully cross-linked with glutaraldehyde and then reduced by sodium borohydride to form a stable carbon-nitrogen single bond. The separation process is solely gravity-driven, and the mesh can separate a range of different oil/water mixtures with >99% separation efficiency in hyper-saline and broad pH range conditions. We envision that such a separation method will be useful in oil spill cleanup and industrial oily wastewater treatment in extreme environments.
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A cascade cross-coupling hydrogen evolution reaction by visible light catalysis.
J. Am. Chem. Soc.
PUBLISHED: 10-31-2013
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Cross-dehydrogenative-coupling reaction has long been recognized as a powerful tool to form a C-C bond directly from two different C-H bonds. Most current processes are performed by making use of stoichiometric amounts of oxidizing agents. We describe here a new type of reaction, namely cross-coupling hydrogen evolution (CCHE), with no use of any sacrificial oxidants, and only hydrogen (H2) is generated as a side product. By combining eosin Y and a graphene-supported RuO2 nanocomposite (G-RuO2) as a photosensitizer and a catalyst, the desired cross-coupling products and H2 are achieved in quantitative yields under visible light irradiation at room temperature.
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3-Aroylmethylene-2,3,6,7-tetrahydro-1H-pyrazino[2,1-a]isoquinolin-4(11bH)-ones as Potent Nrf2/ARE Inducers in Human Cancer Cells and AOM-DSS Treated Mice.
J. Med. Chem.
PUBLISHED: 10-09-2013
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Nrf2-mediated activation of ARE regulates expression of cytoprotective enzymes against oxidative stress, inflammation, and carcinogenesis. We have discovered a novel structure (1) as an ARE inducer via luciferase reporter assay to screen the in-house database of our laboratory. The potency of 1 was evaluated by the expression of NQO-1, HO-1, and nuclear translocation of Nrf2 in HCT116 cells. In vivo potency of 1 was studied using AOM-DSS models, showing that the development of colorectal adenomas was significantly inhibited. Administration with 1 lowered the expression of IL-6, IL-1?, and promoted Nrf2 nuclear translocation. These results indicated that 1 is a potent Nrf2/ARE activator, both in vitro and in vivo. Forty-one derivatives were synthesized for SAR study, and a more potent compound 17 was identified. To our knowledge, this is a potent ARE activator. Besides, its novel structure makes it promising for further optimization.
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Size tunable fluorescent nano-graphite oxides: preparation and cell imaging applications.
Phys Chem Chem Phys
PUBLISHED: 10-08-2013
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Fluorescent nano-graphite oxides (NGO) with different size distribution were prepared via a one-pot hydrothermal route using ultrasmall graphite powder as starting material and subsequently separated using dialysis tubes with different molecular weight cutoff. The biomedical applications of these NGO for cell imaging were further investigated. Fourier transform infrared spectra demonstrated that many functional groups including the hydroxyl group, carboxyl group and epoxy group were present on NGO, which endowed them with good water solubility. These NGO showed size-dependent photoluminescence and excellent biocompatibility with A549 cells. As evidenced by laser scanning confocal microscopy images, NGO could be internalized by A549 cells and located in the cytoplasm. Given their good water solubility, size tunable photoluminescence and excellent biocompatibility, these NGO should be promising for bioimaging and various biomedical applications.
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[Characterization of the primary structure of TNK-tissue plasminogen activator using LC-MS].
Yao Xue Xue Bao
PUBLISHED: 08-30-2013
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The primary structure of TNK-tissue plasminogen activator (TNK-tPA) was characterized using liquid chromatography-mass spectrometry (LC-MS). Firstly, the molecular mass of deglycosylated protein was measured. Then peptide mass mapping and MS/MS of the reduced, alkylated and trypsin-digested sample were tested and analyzed so as to verify its amino acid sequence and identify post-translational modifications. Results show that the amino acid sequence was consistent with designed structure; about 5% of M207 was oxidized; T61 was fucosylated with -80% occupancy; N103, N448 and N184 (-15% occupancy) were glycosylated with complex-type oligosaccharides. LC-MS coupled with proper sample pretreatment is approved to be a rapid and powerful approach to characterize the primary structure of TNK-tPA.
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[Thrichosanthin enhances cisplatin-induced laryngocarcinoma apoptosis through inhibiting transcription factor nuclear factor ?B].
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 07-27-2013
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To investigate the combined effect of thrichosanthin (TCS) and cisplatin on Hep-2 and AMC-HN-8 cell proliferation.
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Level set segmentation of medical images based on local region statistics and maximum a posteriori probability.
Comput Math Methods Med
PUBLISHED: 07-18-2013
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This paper presents a variational level set method for simultaneous segmentation and bias field estimation of medical images with intensity inhomogeneity. In our model, the statistics of image intensities belonging to each different tissue in local regions are characterized by Gaussian distributions with different means and variances. According to maximum a posteriori probability (MAP) and Bayes rule, we first derive a local objective function for image intensities in a neighborhood around each pixel. Then this local objective function is integrated with respect to the neighborhood center over the entire image domain to give a global criterion. In level set framework, this global criterion defines an energy in terms of the level set functions that represent a partition of the image domain and a bias field that accounts for the intensity inhomogeneity of the image. Therefore, image segmentation and bias field estimation are simultaneously achieved via a level set evolution process. Experimental results for synthetic and real images show desirable performances of our method.
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Improved detection of variants in recombinant human interferon alpha-2a products by reverse-phase high-performance liquid chromatography on a core-shell stationary phase.
J Pharm Biomed Anal
PUBLISHED: 06-18-2013
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The detection of variants is one of the important aspects in quality control of recombinant DNA drugs. In this study, a gradient reverse-phase high-performance liquid chromatography (RP-HPLC) method with fluorescence detection is described for the separation of interferon alpha-2a (rhIFN ?-2a) from several product related variants. The methodology employed a core-shell C18 column with a linear gradient elution of 0.2% (v/v) trifluoroacetic acid (TFA)-acetonitrile (ACN) at 1.0mL/min, and the temperature of the column was maintained at 60°C. The method was validated in terms of linearity, sensitivity, intra- and inter-day variations. Compared to the European Pharmacopeia RP-HPLC method of rhIFN ?-2a analysis, this new method can separate N-methionylated variant in both drug substance and finished product, and analyze the variants in untreated, oxidized sample and slightly degraded samples more efficiently. In conclusion the method has an improved capability to detect variants in rhIFN ?-2a products.
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Synthesis, structures and luminescent properties of a series of novel Sr(II)-Ln(III) (Ln = Eu, Gd, Tb) coordination polymers.
Dalton Trans
PUBLISHED: 06-10-2013
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Eight novel Sr(II)-Ln(III) heteronuclear coordination polymers based on pyridine-2,6-dicarboxylic acid (H2pda) and imidazole (im) ligands, namely, [LnSr(pda)3(H2O)5]·Him·H2O (Ln = Eu (1), Gd (2), Tb (3)), [Ln2Sr(pda)6(H2O)5]·4Him·C2H5OH·nH2O (Ln = Eu (4), n = 5; Gd (5), n = 4), [LnSr(pda)3(H2O)4]·Him·3H2O (Ln = Gd (6), Tb (7)), and [GdSr(pda)3(H2O)5]·Him·C2H5OH·3H2O (8), have been prepared by employing different amounts of imidazole. X-ray crystal structure analysis reveals that these compounds exhibit a rich structural chemistry. Complexes 1-3 possess 2-D frameworks. Complexes 4-5, 6-7, and 8 exhibit three types of 1-D chain structure. The structures of the complexes could be rationally tuned via adding different amounts of imidazole. The luminescent properties of these complexes have been investigated. The results show that Eu(III) and Tb(III) complexes exhibit intense red and green luminescence emission which are characteristics of Tb(III) and Eu(III), respectively. Solid-state quantum yield and the lifetime of these complexes are also reported.
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An oxygen enrichment device for lowlanders ascending to high altitude.
Biomed Eng Online
PUBLISHED: 06-05-2013
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When ascending to the high altitude, people living in low altitude areas will suffer from acute mountain sickness. The aim of this study is to test the hypothesis that whether an oxygen concentration membrane can be made and used to construct a new portable oxygen enrichment device for individuals in acute exposure to the high altitude.
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Large scale preparation of graphene quantum dots from graphite with tunable fluorescence properties.
Phys Chem Chem Phys
PUBLISHED: 05-16-2013
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We report an improved Hummers method for synthesizing graphene quantum dots (GQDs) by directly oxidizing and etching graphite powders. The yield of GQDs is as high as 63 ± 7% (by weight, wt%), suggesting this technique is suitable for producing GQDs on a large scale. The GQDs are nanocrystals with lateral dimensions in the range of 2-4 nm and an average thickness of around 1.3 nm. The emission peaks of as-prepared GQDs can be tuned in the range of 440 to 510 nm by varying the reaction conditions. Their fluorescence quantum yields were tested to be around 1%, which could be further increased to about 3% by hydrothermal treatment. These GQDs have low cytotoxicity and excellent biocompatibility, indicating that they are promising for biological applications.
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Mussel-inspired chemistry and Michael addition reaction for efficient oil/water separation.
ACS Appl Mater Interfaces
PUBLISHED: 05-06-2013
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An oil/water separation mesh with high separation efficiency and intrusion pressure of water has been successfully developed by combining mussel-inspired chemistry and Michael addition reaction. The substrate of the stainless steel mesh was first coated with the adhesive polydopamine (PDA) film by simple immersion in an aqueous solution of dopamine at pH of 8.5. Then n-dodecyl mercaptan (NDM) was conjugated with PDA film through Michael addition reaction at ambient temperature. The as-prepared mesh showed highly hydrophobicity with the water contact angle of 144° and superoleophilicity with the oil contact angle of 0°. It can be used to separate a series of oil/water mixtures like gasoline, diesel, etc. The separation efficiency remains high after 30 times use (99.95% for hexane/water mixture). More importantly, the relatively high intrusion pressure (2.2 kPa) gives the opportunity to separation of large amount of oil and water mixtures. This study provides a new prospect to simply introduce multiple molecules on the adhesive PDA-based mesh to achieve various functional oil/water separation materials.
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Nonionic polymer cross-linked chitosan hydrogel: preparation and bioevaluation.
J Biomater Sci Polym Ed
PUBLISHED: 04-08-2013
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A straightforward method to prepare nonionic polymer (polyacrylamide, PAM) cross-linked chitosan hydrogel has been developed. The chitosan-polyacrylamide (CS-PAM) hydrogel could be quickly obtained by simply mixing of chitosan and polyacrylamide solutions under very benign condition (room temperature, <30?s). The cytotoxicity and hemocompatibility of the CS-PAM hydrogel were subsequently investigated. Cells retained normal morphology even when the concentration of CS-PAM hydrogel in culture system was as high as 640??g?mL(-1), indicating the CS-PAM hydrogel has minimal cytotoxicity to A549 and HeLa cells. Meanwhile, no hemolysis was observed after incubating the CS-PAM hydrogel with red blood cells for 6?h, further suggesting excellent biocompatibility of the hydrogel. Scanning electron microscopy images illustrated that the CS-PAM hydrogel can absorb red blood cells through the interaction between the protonated amine groups on chitosan and the negative charged residues on red blood cell membranes. Given its low cost, simple preparation, and excellent biocompatibility, this CS-PAM hydrogel might be a potential biomaterial for future healthcare and biomedical applications.
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Synthesis and bioevaluation of a series of ?-pyrone derivatives as potent activators of Nrf2/ARE pathway (part I).
Eur J Med Chem
PUBLISHED: 04-03-2013
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When exposed to electrophiles, human colorectal cancer cells (HCT116) counteract oxidative stress through activating NF-E2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway. To identify new activators, luciferase reporter gene assay was used to screen in-house database of our laboratory, leading to a novel ?-pyrone compound 1 as a hit. 2 with 2-fluoro phenyl group exhibited the strongest ARE inductive activity in the first round structure-activity relationship (SAR) study. Biological studies showed the compound induced nuclear translocation of Nrf2 preceded by phosphorylation of ERK1/2. The data encouraged us to use 2 as lead and 20 derivatives were synthesized to discuss a more detailed SAR, leading to a more potent compound 9, which can be the starting compound for further modification.
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HQS-3, a newly synthesized flavonoid, possesses potent anti-tumor effect in vivo and in vitro.
Eur J Pharm Sci
PUBLISHED: 03-22-2013
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HQS-3 is a newly baicalein derivative with a benzene substitution. We investigated the anticancer effect of HQS-3 in vivo and in vitro. HQS-3 significantly decreased tumor growth in mice inoculated with Heps and HepG2 cells; and had little influence on the state and weight of animals. After treatment with 20 mg/kg HQS-3, the inhibitory rate of tumor weight in mice inoculated with Heps and HepG2 cells were 63.62% and 68.03%, respectively. Meanwhile, HQS-3 inhibited the viability of various kinds of tumor cells with IC50 values in the range of 22.98-54.32 ?M after 48 h treatment measured by MTT-assay. HQS-3 remarkably inhibited viability of hepatoma cells in a concentration- and time-dependent manner and induced apoptosis in HepG2 cells by DAPI staining and Annexin V/PI double staining. The apoptosis-induction effect of HQS-3 was attributed to its ability to modulate the activity of caspase-9, caspase-3 and PARP. Moreover, the expression of bax protein was increased while the bcl-2 protein was decreased, leading to an increase in Bax/Bcl-2 ratio. The accumulation of ROS induced by HQS-3 in HepG2 cells was also observed. The further results suggested that HQS-3 induced mitochondrial-mediated apoptosis by increasing ROS level and inhibiting the expression of anti-oxidative protein SOD2. HQS-3 exerted anti-tumor activity both in vitro and in vivo via inducing tumor cells apoptosis, and these results suggested that it deserves further investigation as a novel chemotherapy for human tumors.
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LC-ESI-MS method for the determination of dexamethasone acetate in skin of nude mouse.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 03-18-2013
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A high-performance liquid chromatography-positive electrospray ionization single quadrupole mass spectrometric (LC-ESI-MS) method for the determination of dexamethasone acetate in skin of nude mouse using triamcinolone acetonide acetate as the internal standard (I.S.) was developed and fully validated. Both compounds were precipitated from skin homogenate with methanol and were separated by HPLC on a Shimadzu Shim-pack VP-ODS C18 column (150mm×2.0mm, 5?m) with a mobile phase of methanol-water (80:20, v/v) at a flow rate of 0.2mL/min. Calibration curves were linear over the range of 0.05-5?g/mL. The intra-run relative standard deviations were less than 9.59%. The inter-run relative standard deviations were less than 7.82%. The mean recovery was in the ranges of 89.95-95.97%, respectively. The method was successfully applied to determinate the concentration of dexamethasone acetate in skin and study the percutaneous absorption process in skin of nude mouse.
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Localized FCM Clustering with Spatial Information for Medical Image Segmentation and Bias Field Estimation.
Int J Biomed Imaging
PUBLISHED: 03-16-2013
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This paper presents a novel fuzzy energy minimization method for simultaneous segmentation and bias field estimation of medical images. We first define an objective function based on a localized fuzzy c-means (FCM) clustering for the image intensities in a neighborhood around each point. Then, this objective function is integrated with respect to the neighborhood center over the entire image domain to formulate a global fuzzy energy, which depends on membership functions, a bias field that accounts for the intensity inhomogeneity, and the constants that approximate the true intensities of the corresponding tissues. Therefore, segmentation and bias field estimation are simultaneously achieved by minimizing the global fuzzy energy. Besides, to reduce the impact of noise, the proposed algorithm incorporates spatial information into the membership function using the spatial function which is the summation of the membership functions in the neighborhood of each pixel under consideration. Experimental results on synthetic and real images are given to demonstrate the desirable performance of the proposed algorithm.
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High CCR6/CCR7 expression and Foxp3+ Treg cell number are positively related to the progression of laryngeal squamous cell carcinoma.
Oncol. Rep.
PUBLISHED: 03-12-2013
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Chemokine receptors CCR6 and CCR7 have been reported to play important roles in T cell migration and organ-specific metastasis of various tumors. In the present study, we evaluated the expression and clinical significance of CCR6, CCR7, their ligands and CD4+CD25+Foxp3+ regulatory T cells in laryngeal squamous cell carcinoma (LSCC) and metastatic lymph nodes (LNs). The expression of CCR6, CCR7 and their ligands mRNA (CCL20, CCL19/CCL21) as well as the CCR6 and CCR7 proteins were detected by real-time RT-PCR and immunohistochemistry (IHC), respectively. Flow cytometry was used to investigate the percentage of CD4+CD25+Foxp3+ regulatory T cells (Tregs) in peripheral blood mononuclear cells (PBMCs). Furthermore, a number of cytokines, including interleukin (IL)-2, IL-4, IL-10, IL-12p70, interferon (IFN)-? and transforming growth factor (TGF)-?1 were detected by ELISA. The results showed that CCR6 and CCR7 were expressed in tumors in situ, metastatic LNs and CD4+CD25+Foxp3+ Tregs. It was hypothesized that the expression profile of CCR6, CCR7 and the proliferation of CD4+CD25+Foxp3+ Tregs affected the process of LN metastasis in LSCC patients. Therefore, the increased percentage of the Foxp3+ Tregs and the upregulation of Foxp3 expression on CCR6+ Tregs in LSCC patients may have accounted for the downregulation of antitumor immunity in these patients, which could be valuable for assessment of prognosis in LSCC treatment.
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The effect of microdosimetric 12C6+ heavy ion irradiation and Mg2+ on canthaxanthin production in a novel strain of Dietzia natronolimnaea.
BMC Microbiol.
PUBLISHED: 03-10-2013
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Dietzia natronolimnaea is one of the most important bacterial bioresources for high efficiency canthaxanthin production. It produces the robust and stable pigment canthaxanthin, which is of special interest for the development of integrated biorefineries. Mutagenesis employing 12C6+ irradiation is a novel technique commonly used to improve microorganism productivity. This study presents a promising route to obtaining the highest feasible levels of biomass dry weight (BDW), and total canthaxanthin by using a microdosimetric model of 12C6+ irradiation mutation in combination with the optimization of nutrient medium components.
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Facile incorporation of aggregation-induced emission materials into mesoporous silica nanoparticles for intracellular imaging and cancer therapy.
ACS Appl Mater Interfaces
PUBLISHED: 03-05-2013
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Aggregation-induced emission (AIE) materials were facilely incorporated into mesoporous silica nanoparticles (MSNs) via one-pot surfactant templated method. Cell imaging and cancer therapy applications of such fluorescent MSNs were further explored. We demonstrated that AIE-MSN nanocomposites showed strong fluorescence and uniform morphology, making them promising for both cell imaging and cancer therapy.
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Oxidative stress is not involved in motion sickness in mice.
CNS Neurosci Ther
PUBLISHED: 02-27-2013
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Some indirect evidences indicate a possible correlation between oxidative stress and motion sickness. The aim of this research was to investigate whether oxidative stress contributing to motion sickness in mice or not.
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Degradation of p-nitrophenol in a BES-Fenton system based on limonite.
J. Hazard. Mater.
PUBLISHED: 02-21-2013
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This study confirmed the feasibility of natural limonite working as the iron catalyst for the PNP wastewater treatment in the BES-Fenton system. After the start-up period of the BES-Fenton systems, air and limonite powder were injected into the cathode chamber as the original materials for manufacturing Fenton reagents of H?O? and Fe(II) respectively. The experiment parameters like pH, external resistance, limonite dosage and initial PNP concentration were investigated in this research. The removal efficiency of PNP (0.25 mM) could achieve 96% in 6h under the optimal experimental conditions. A limonite dosage of 112 mg per 50 ml of PNP solution at 0.25 mM concentration each time could sustain 7 cycles of the BES-Fenton system operation with PNP removal efficiency >94%. This study suggests an efficiency and cost-effective approach for the PNP removal by using the natural limonite as the iron catalyst of the BES-Fenton system.
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Monoclonal antibody-based fluorescence polarization immunoassay for high throughput screening of furaltadone and its metabolite AMOZ in animal feeds and tissues.
Comb. Chem. High Throughput Screen.
PUBLISHED: 02-18-2013
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A simple and fast homogeneous fluorescent polarization immunoassay (FPIA) was developed for the determination of furaltadone and its metabolite 3-amino-5-methylmorpholino-2-oxazolidinone (AMOZ). Monoclonal antibody with high cross-reactivity to furaltadone and the nitrophenyl derivative of AMOZ (NPAMOZ) were produced against a novel immunogen and the effects of several synthesized tracers on FPIA sensitivity studied. The proposed FPIA, using an optimum antibody and tracer pair, had an IC?? of 4.3 µg L?¹ and limit of detection at 0.6 µg L?¹ for furaltadone, and 2.7 µgL?¹ and 0.3 µg L?¹ for NPAMOZ. Recoveries of furaltadone from animal feeds by FPIA ranged from 79.6 to 87.7%, while recoveries of AMOZ from animal tissues ranged from 72.9 to 83.1%. Good correlation (R>0.99) between the results of this FPIA and a standard analytical method was obtained. The FPIA does not require separation or washing steps and the total time required for equilibrium of the antibody-tracer interaction is only 10 min. These results indicated that the proposed FPIA offers great potential and utility for the high throughput screening of furaltadone residues in animal feed and its metabolite AMOZ residues in animal tissues.
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Synthesis of biotinylated aldehyde polymers for biomolecule conjugation.
Macromol Rapid Commun
PUBLISHED: 02-16-2013
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Biotinylated polymers with side-chain aldehydes were prepared for use as multifunctional scaffolds. Two different biotin-containing chain transfer agents (CTAs) and an aldehyde-containing monomer, 6-oxohexyl acrylate (6OHA), are synthesized. Poly(ethylene glycol) methyl ether acrylate (PEGA) and 6OHA are copolymerized by reversible addition-fragmentation chain transfer (RAFT) polymerization in the presence of the biotinylated CTAs. The resulting polymers are analyzed by GPC and(1) H NMR spectroscopy. The polymer end groups contained a disulfide bond, which could be readily reduced in solution to remove the biotin. Reactivity of the aldehyde side chains is demonstrated by oxime and hydrazone formation at the polymer side chains, and conjugate formation of fluorescently labeled polymers with streptavidin is investigated by gel electrophoresis.
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Carbon-dots derived from nanodiamond: photoluminescence tunable nanoparticles for cell imaging.
J Colloid Interface Sci
PUBLISHED: 01-29-2013
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Water dispersible carbon-dots (CDs) with tunable photoluminescence were synthesized via one-pot hydrothermal oxidation of nanodiamond and subsequently utilized for cell imaging applications. The CDs were characterized by the following techniques including transmission electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, UV-Visible spectroscopy, and fluorescent spectroscopy. Results showed that the size of CDs is mainly distributed at 3-7 nm. Many functional groups were introduced on the surface of CDs during hydrothermal oxidation procedure. Cell morphology observation and cell viability measurement demonstrated the good biocompatibility of CDs, suggesting their potential bioimaging applications.
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Synthesis and evaluation of gambogic acid derivatives as antitumor agents. Part III.
Chem. Biodivers.
PUBLISHED: 01-24-2013
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Gambogic acid (GA) has been reported as a potent apoptosis inducer. Previously, we have reported chemical modification at C(34) and C(39) of GA, leading to some agents with improved activity. To investigate the further structure-activity relationship (SAR) and preliminary mechanism of GA activity, a series of derivatives with modified prenyl side chains of GA were synthesized and evaluated. Most of the derivatives showed potent inhibitory activities against the proliferation of HepG2 and A549 cell lines. Compound 4 was selected for further mechanistic studies due to its outstanding activity. It was established that 4 induces the apoptosis of HepG2 cells by using Annexin-V/PI double staining and Western blot assay, thus, compound 4 can serve as a promising lead compound for the development of novel apoptosis in anticancer treatment.
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Removal of heavy metals from fly ash leachate using combined bioelectrochemical systems and electrolysis.
J. Hazard. Mater.
PUBLISHED: 01-20-2013
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Based on environmental and energetic analysis, a novel combined approach using bioelectrochemical systems (BES) followed by electrolysis reactors (ER) was tested for heavy metals removal from fly ash leachate, which contained high detectable levels of Zn, Pb and Cu according to X-ray diffraction analysis. Acetic acid was used as the fly ash leaching agent and tested under various leaching conditions. A favorable condition for the leaching process was identified to be liquid/solid ratio of 14:1 (w/w) and leaching duration 10h at initial pH 1.0. It was confirmed that the removal of heavy metals from fly ash leachate with the combination of BESs and ER is feasible. The metal removal efficiency was achieved at 98.5%, 95.4% and 98.1% for Cu(II), Zn(II), and Pb(II), respectively. Results of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) indicated that Cu(II) was reduced and recovered mainly as metal Cu on cathodes related to power production, while Zn(II) and Pb(II) were not spontaneously reduced in BESs without applied voltage and basically electrolyzed in the electrolysis reactors.
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The Composition of Microbiome in Larynx and the Throat Biodiversity between Laryngeal Squamous Cell Carcinoma Patients and Control Population.
PLoS ONE
PUBLISHED: 01-01-2013
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The throat is an ecological assemblage involved human cells and microbiota, and the colonizing bacteria are important factors in balancing this environment. However, this bacterial community profile has thus been poorly investigated. The purpose of this study was to investigate the microbial biology of the larynx and to analyze the throat biodiversity in laryngeal carcinoma patients compared to a control population in a case-control study. Barcoded pyrosequencing analysis of the 16S rRNA gene was used. We collected tissue samples from 29 patients with laryngeal carcinoma and 31 control patients with vocal cord polyps. The findings of high-quality sequence datasets revealed 218 genera from 13 phyla in the laryngeal mucosa. The predominant communities of phyla in the larynx were Firmicutes (54%), Fusobacteria (17%), Bacteroidetes (15%), Proteobacteria (11%), and Actinobacteria (3%). The leading genera were Streptococcus (36%), Fusobacterium (15%), Prevotella (12%), Neisseria (6%), and Gemella (4%). The throat bacterial compositions were highly different between laryngeal carcinoma subjects and control population (p?=?0.006). The abundance of the 26 genera was significantly different between the laryngeal cancer and control groups by metastats analysis (p<0.05). Fifteen genera may be associated with laryngeal carcinoma by partial least squares discriminant analysis (p<0.001). In summary, this study revealed the microbiota profiles in laryngeal mucosa from tissue specimens. The compositions of bacteria community in throat were different between laryngeal cancer patients and controls, and probably were related with this carcinoma. The disruption of this bio-ecological niche might be a risk factor for laryngeal carcinoma.
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Therapeutic effects of 15 Hz pulsed electromagnetic field on diabetic peripheral neuropathy in streptozotocin-treated rats.
PLoS ONE
PUBLISHED: 01-01-2013
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Although numerous clinical studies have reported that pulsed electromagnetic fields (PEMF) have a neuroprotective role in patients with diabetic peripheral neuropathy (DPN), the application of PEMF for clinic is still controversial. The present study was designed to investigate whether PEMF has therapeutic potential in relieving peripheral neuropathic symptoms in streptozotocin (STZ)-induced diabetic rats. Adult male Sprague-Dawley rats were randomly divided into three weight-matched groups (eight in each group): the non-diabetic control group (Control), diabetes mellitus with 15 Hz PEMF exposure group (DM+PEMF) which were subjected to daily 8-h PEMF exposure for 7 weeks and diabetes mellitus with sham PEMF exposure group (DM). Signs and symptoms of DPN in STZ-treated rats were investigated by using behavioral assays. Meanwhile, ultrastructural examination and immunohistochemical study for vascular endothelial growth factor (VEGF) of sciatic nerve were also performed. During a 7-week experimental observation, we found that PEMF stimulation did not alter hyperglycemia and weight loss in STZ-treated rats with DPN. However, PEMF stimulation attenuated the development of the abnormalities observed in STZ-treated rats with DPN, which were demonstrated by increased hind paw withdrawal threshold to mechanical and thermal stimuli, slighter demyelination and axon enlargement and less VEGF immunostaining of sciatic nerve compared to those of the DM group. The current study demonstrates that treatment with PEMF might prevent the development of abnormalities observed in animal models for DPN. It is suggested that PEMF might have direct corrective effects on injured nerves and would be a potentially promising non-invasive therapeutic tool for the treatment of DPN.
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[Isolation and in vitro characterization of CD133(+) side population cells from laryngeal cancer cell line].
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 12-20-2011
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To investigate an approach enriching cancer stem cells (CSCs) more effectively from laryngeal cancer cell line.
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Brønsted acid-catalyzed enantioselective Friedländer condensations: achiral amine promoter plays crucial role in the stereocontrol.
Chem. Commun. (Camb.)
PUBLISHED: 09-26-2011
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A highly enantioselective Friedländer condensation has been established by using chiral Brønsted acids in combination with achiral amines to give quinolines in high yields (up to 99%) and with excellent enantioselectivities (up to 95%).
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Monoclonal antibody-based broad-specificity immunoassay for monitoring organophosphorus pesticides in environmental water samples.
J Environ Monit
PUBLISHED: 09-14-2011
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The development of easy-to-use and rapid-monitoring immunoassay methods for organic environmental pollutants in a class-selective manner is a topic of considerable environmental interest. In this work, a heterologous competitive indirect enzyme-linked immunosorbent assay (ciELISA) based on a monoclonal antibody (MAb) with broad-specificity for organophosphorus pesticides (OPs) was applied to the detection of O,O-diethyl and O,O-dimethyl OPs in water samples. The ciELISA conditions were carefully optimized to obtain a three to five-fold improvement of sensitivity for most OPs, and thirteen OPs were determined at concentrations ranging from 0.017 to 30 ng mL(-1). The determination of spiked environmental water samples showed average recoveries from 81.5% to 115.1%, with the coefficient of variation (CV) ranging from 6.1% to 20.9%, which showed satisfactory reproducibility of the developed ciELISA. To overcome the negative aspect of broad-specificity immunoassays not providing qualitative and quantitative analysis of individual OPs in blind samples, we used "percent inhibition rate" to make the developed ciELISA a semi-quantitative method, which allows the monitoring of positive samples from hundreds of negative samples. The determination of OPs in blind water samples by the developed ELISA with confirmation by HPLC-MS/MS analysis demonstrated that the assay is ideally suited as a screening method for OP residues prior to chromatographic analysis.
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[Metastatic tumors in nasal cavity and pharynx: a clinicopathological analysis of 11 cases].
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 09-03-2011
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To investigate the clinicopathological characteristics, diagnosis and differential diagnosis of metastatic tumors in nasal cavity and pharynx.
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[Clinical efficacy of subcutaneous and sublingual immunotherapy in mite-sensitized patients with allergic rhinitis].
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 09-03-2011
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To investigate the clinical efficacy of subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) with standardized house dust mite (HDM) extract for persistent allergic rhinitis (PER).
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A simple, rapid and high-throughput fluorescence polarization immunoassay for simultaneous detection of organophosphorus pesticides in vegetable and environmental water samples.
Anal. Chim. Acta
PUBLISHED: 08-12-2011
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A simple, rapid and high-throughput fluorescent polarization immunoassay (FPIA) for simultaneous determination of organophosphorus pesticides (OPs) using a broad-specificity monoclonal antibody was developed. The effects of tracer structure, tracer concentration, antibody dilution, methanol content and matrix effect on FPIA performance were studied. The FPIA can detect 5 OPs simultaneously with a limit of detection below 10 ng mL(-1). The time required for the equilibrium of antibody-antigen interaction was less than 10 min. The recovery from spiked vegetable and environmental samples ranged from 71.3% to 126.8%, with the coefficient of variations ranging from 3.5% to 14.5%. The developed FPIA was applied to samples, followed by confirmation with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis. The developed FPIA demonstrated good accuracy and reproducibility, and is suitable for rapid and high-throughput screening for OP contamination with high-efficiency and low cost.
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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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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.