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Find video protocols related to scientific articles indexed in Pubmed.
Establishment of a proteome profile and identification of molecular markers for mouse spermatogonial stem cells.
J. Cell. Mol. Med.
PUBLISHED: 12-24-2014
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Spermatogonial stem cells (SSCs) are undifferentiated cells that are required to maintain spermatogenesis throughout the reproductive life of mammals. Although SSC transplantation and culture provide a powerful tool to identify the mechanisms regulating SSC function, the precise signalling mechanisms governing SSC self-renewal and specific surface markers for purifying SSCs remain to be clearly determined. In the present study, we established a steady SSC culture according to the method described by Shinohara's lab. Fertile progeny was produced after transplantation of cultured SSCs into infertile mouse testis, and the red fluorescence exhibited by the culture cell membranes was stably and continuously transmitted to the offspring. Next, via advanced mass spectrometry and an optimized proteomics platform, we constructed the proteome profile, with 682 proteins expressed in SSCs. Furthermore bioinformatics analysis showed that the list contained several known molecules that are regulated in SSCs. Several nucleoproteins and membrane proteins were chosen for further exploration using immunofluorescence and RT-PCR. The results showed that SALL1, EZH2, and RCOR2 are possibly involved in the self-renewal mechanism of SSCs. Furthermore, the results of tissue-specific expression analysis showed that Gpat2 and Pld6 were uniquely and highly expressed in mouse testes and cultured SSCs. The cellular localization of PLD6 was further explored and the results showed it was primarily expressed in the spermatogonial membrane of mouse testes and cultured SSCs. The proteins identified in this study form the basis for further exploring the molecular mechanism of self-renewal in SSCs and for identifying specific surface markers of SSCs.
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Synthesis, in Vitro Covalent Binding Evaluation, and Metabolism of (14)C-Labeled Inhibitors of 11?-HSD1.
ACS Med Chem Lett
PUBLISHED: 11-13-2014
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In this letter, we reported the design and synthesis of three potent, selective, and orally bioavailable 11?-HSD1 inhibitors labeled with (14)C: AMG 456 (1), AM-6949 (2), and AM-7715 (3). We evaluated the covalent protein binding of the labeled inhibitors in human liver microsomes in vitro and assessed their potential bioactivation risk in humans. We then studied the in vitro mechanism of 2 in human hepatocytes and the formation of reactive intermediates. Our study results suggest that 1 and 3 have low potential for metabolic bioactivation in humans, while 2 has relatively high risk.
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[Clinical characteristics of whooping cough in neonates and antimicrobial resistance of the pathogenic bacteria].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 10-26-2014
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To study the clinical characteristics of whooping cough in neonates and the antimicrobial resistance of the bacterial isolates.
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Teriflunomide, an immunomodulatory drug, exerts anticancer activity in triple negative breast cancer cells.
Exp. Biol. Med. (Maywood)
PUBLISHED: 10-12-2014
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Triple-negative breast cancer (TNBC) is defined as a group of primary breast cancers lacking expression of estrogen, progesterone, and human epidermal growth factor receptor-2 (HER-2) receptors, characterized by higher relapse rate and lower survival compared with other subtypes. Due to lack of identified targets and molecular heterogeneity, conventional chemotherapy is the only available option for treatment of TNBC, but non-discordant positive therapeutic efficacy could not be achieved. Here, we demonstrated that these TNBC cells were sensitive to teriflunomide, which was a well-known immunomodulatory drug for treatment of relapsing multiple sclerosis (MS). Potent anti-cancer effects in TNBC in vitro, including proliferation inhibition, cell cycle delay, cell apoptosis, and suppression of cell motility and invasiveness, could be achieved with this agent. Of note, we showed that multiple signals involved in TNBC proliferation, survival, migratory, and invasive potential were under regulation by teriflunomide. Among them, we identified down-regulation of growth factor receptors to abolish growth maintenance, suppression of c-Myc, and cyclin D1 to contribute to its anti-proliferative effect, modulation of components of cell cycle to induce S-phase arrest, degradation of Bcl-xL, and up-regulation of BAX via activation of MAPK pathway to induce apoptosis, and inhibition of epithelial-mesenchymal transition (EMT) process, matrix metalloproteinase-9 (MMP9) expression, and inactivation of Src/FAK to reduce TNBC migration and invasion. The results identified teriflunomide may be of therapeutic benefit for the more aggressive and difficult-to-treat breast cancer subtype, indicating the use of teriflunomide for clinical trials for treatment of TNBC patients.
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[Distribution of polycyclic aromatic hydrocarbons in water and sediment from Zhoushan coastal area, China].
Huan Jing Ke Xue
PUBLISHED: 09-24-2014
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The spatial and temporal distribution of 16 polycyclic aromatic hydrocarbons (PAHs) has been investigated in water and sediments of Zhoushan coastal area every two months in 2012. The concentrations of total PAHs ranged from 382.3 to 816.9 ng x L(-1), with the mean value of 552.5 ng x L(-1) in water; whereas it ranged from 1017.9 to 3047.1 ng x g(-1), with the mean value of 2 022.4 ng x g(-1) in sediment. Spatial distribution showed that Yangshan and Yanwoshan offshore area had the maximum and minimum of total PAHs contents in water, while the maximum and minimum occurred at Yangshan and Zhujiajian Nansha offshore area in sediment. Temporal distribution revealed that total PAHs contents in water reached the maximum and minimum values in October and June, however in sediments these values were found in August and June, respectively. The PAHs pollution was affected by oil emission, charcoal and coal combustion. Using the biological threshold and exceeded coefficient method to assess the ecological risk of PAHs in Zhoushan coastal area, the result showed that sigma PAHs had a lower probability of potential risk, while there was a higher probability of potential risk for acenaphthylene monomer, and there might be ecological risk for acenaphthene and fluorene. Distribution of PAHs between sediment and water showed that Zhoushan coastal sediment enriched a lot of PAHs, meanwhile the enrichment coefficient (K(d) value) of sediment in Daishan island was larger than that in Zhoushan main island.
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[Efficacy observation on fire needling therapy for moderate to severe acne vulgaris].
Zhongguo Zhen Jiu
PUBLISHED: 09-20-2014
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To compare the efficacy differences between fire needling therapy and oxycycline tablets for the treatment of moderate to severe acne vulgaris.
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LGR5, a relevant marker of cancer stem cells, indicates a poor prognosis in colorectal cancer patients: A meta-analysis.
Clin Res Hepatol Gastroenterol
PUBLISHED: 09-02-2014
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Leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5) has been identified as a putative intestinal stem cell marker. However, the clinical prognosis of Lgr5 is still controversial in colorectal cancer (CRC). To systematically summarize the clinical prognostic function of Lgr5 in colorectal cancer, we performed this meta-analysis.
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[Etiological and molecular characteristics of diarrhea caused Proteus mirabilis].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 09-02-2014
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To analyze the etiological characteristics, virulence genes and plasmids that carrying diarrhea-causing Proteus mirabilis and to assess their relationship with drug resistance and pathogenicity.
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Effects of sediment geochemical properties on heavy metal bioavailability.
Environ Int
PUBLISHED: 08-29-2014
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As the largest container and resource of metals, sediment has a special role in the fate of metals. Factors influencing bioavailability of heavy metals in sediment have never been comprehensively considered and the sediment properties still fail to understand and even controversial. In this review, the mechanisms of sediment properties such as acid-volatile sulfides (AVS), organic matter, texture (clay, silt or sand) and geology, organism behaviors as well as those influencing the bioavailability of metals were analyzed. Under anoxic condition, AVS mainly reduce the solubility and toxicity of metals, while organic matters, Fe-Mn oxides, clay or silt can stabilize heavy metals in elevated oxidative-reductive potential (ORP). Other factors including the variation of pH, redox potential, aging as well as nutrition and the behavior of benthic organism in sediment also largely alter metals mobility and distribution. These factors are often inter-related, and various toxicity assessment methods used to evaluate the bioavailability of trace metals have been also discussed. Additionally, we expect that some novel synthetic materials like polysulfides, nano-materials, provide the substantial amendments for metals pollution in sediment.
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Methylglyoxal induces systemic symptoms of irritable bowel syndrome.
PLoS ONE
PUBLISHED: 08-26-2014
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Patients with irritable bowel syndrome (IBS) show a wide range of symptoms including diarrhea, abdominal pain, changes in bowel habits, nausea, vomiting, headache, anxiety, depression and cognitive impairment. Methylglyoxal has been proved to be a potential toxic metabolite produced by intestinal bacteria. The present study was aimed at investigating the correlation between methylglyoxal and irritable bowel syndrome. Rats were treated with an enema infusion of methylglyoxal. Fecal water content, visceral sensitivity, behavioral tests and serum 5-hydroxytryptamine (5-HT) were assessed after methylglyoxal exposure. Our data showed that fecal water content was significantly higher than controls after methylglyoxal exposure except that of 30 mM group. Threshold volumes on balloon distension decreased in the treatment groups. All exposed rats showed obvious head scratching and grooming behavior and a decrease in sucrose preference. The serum 5-HT values were increased in 30, 60, 90 mM groups and decreased in 150 mM group. Our findings suggested that methylglyoxal could induce diarrhea, visceral hypersensitivity, headache as well as depression-like behaviors in rats, and might be the key role in triggering systemic symptoms of IBS.
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MicroRNA-17/20a inhibits glucocorticoid-induced osteoclast differentiation and function through targeting RANKL expression in osteoblast cells.
Bone
PUBLISHED: 08-17-2014
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Glucocorticoids act on the osteoblasts to up-regulate the expression of RANKL, which is very important in the etiology of glucocorticoid-induced osteoclast differentiation and bone resorption. The mechanisms of this process are still not completely understood. Recent studies have shown that glucocorticoids mediate osteoblast function by decreasing the expression of microRNA-17-92a cluster. Coincidentally, we found that the microRNA-17/20a (microRNA-17, microRNA-20a) seed sequences were also complementary to a sequence conserved in the 3'- untranslated region of RANKL mRNA. Therefore, we hypothesized that glucocorticoids might promote osteoblast-derived RANKL expression by down-regulating microRNA-17/20a, which favors differentiation and function of the osteoclasts. In the present study, Western blot analysis showed that microRNA-17/20a markedly lowered the levels of RANKL protein and attenuated dexamethasone-induced RANKL expression in the osteoblasts. The post-transcriptional repression of RANKL by microRNA-17/20a was further confirmed by the luciferase reporter assay. Furthermore, we found that dexamethasone-induced osteoclast differentiation and function were significantly attenuated in co-culture with osteoblast over-expressed microRNA-17/20a and osteoclast progenitors. These results showed that microRNA-17/20a may play a significant role in glucocorticoid-induced osteoclast differentiation and function by targeting the RANKL expression in osteoblast cells.
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The Tribolium castaneum cell line TcA: a new tool kit for cell biology.
Sci Rep
PUBLISHED: 08-08-2014
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The red flour beetle, Tribolium castaneum, is an agriculturally important insect pest that has been widely used as a model organism. Recently, an adherent cell line (BCIRL-TcA-CLG1 or TcA) was developed from late pupae of the red flour beetle. Next generation transcriptome sequencing of TcA cells demonstrated expression of a wide variety of genes associated with specialized functions in chitin metabolism, immune responses and cellular and systemic RNAi pathways. Accordingly, we evaluated the sensitivity of TcA cells to dsRNA to initiate an RNAi response. TcA cells were highly sensitive to minute amounts of dsRNA, with a minimum effective dose of 100?pg/mL resulting in significant suppression of gene expression. We have also developed a plasmid containing two TcA-specific promoters, the promoter from the 40S ribosomal protein subunit (TC006550) and a bi-directional heat shock promoter (TcHS70) from the intergenic space between heat shock proteins 68a and b. These promoters have been employed to provide high levels of either constitutive (TC006550) or inducible (TcHS70) gene expression of the reporter proteins. Our results show that the TcA cell line, with its sensitivity to RNAi and functional TcA-specific promoters, is an invaluable resource for studying basic molecular and physiological questions.
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Knockdown of glucose-regulated protein 78 enhances poly(ADP-ribose) polymerase cleavage in human pancreatic cancer cells exposed to endoplasmic reticulum stress.
Oncol. Rep.
PUBLISHED: 08-07-2014
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The present study examined the expression of glucose?regulated protein 78 (GRP78/Bip) in human pancreatic cancer cell lines and the effect of knockdown of GRP78 on the cleavage of poly(ADP-ribose) polymerase (PARP). Human pancreatic cancer cell lines (KP-2, MIAPaCa-2, Panc-1 and SUIT-2), constitutively expressed GRP78. We also demonstrated that ER stress induced by thapsigargin upregulated protein levels of GRP78. In the presence of thapsigargin, knockdown of GRP78 enhanced the PARP cleavage in the human pancreatic cancer cells. These results provide evidence that GRP78 is a potential therapeutic target for 'difficult-to-treat' pancreatic cancer, in which ER stress signaling in part falls into disorder.
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3-Deazaneplanocin?A and Neplanocin?A Analogues and Their Effects on Apoptotic Cell Death.
ChemMedChem
PUBLISHED: 07-26-2014
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3-Deazaneplanocin?A (DzNep) is a potential epigenetic drug for the treatment of various cancers. DzNep has been reported to deplete histone methylations, including oncogenic EZH2 complex, giving rise to epigenetic modifications that reactivate many silenced tumor suppressors in cancer cells. Despite its promise as an anticancer drug, little is known about the structure-activity relationships of DzNep in the context of epigenetic modifications and apoptosis induction. In this study, a number of analogues of DzNep were examined for DzNep-like ability to induce synergistic apoptosis in cancer cells in combination with trichostatin?A, a known histone deacetylase (HDAC) inhibitor. The structure-activity relationship data thus obtained provide valuable information on the structural requirements for biological activity. The studies identified three compounds that show similar activities to DzNep. Two of these compounds show good pharmacokinetics and safety profiles. Attempts to correlate the observed synergistic apoptotic activities with measured S-adenosylhomocysteine hydrolase (SAHH) inhibitory activities suggest that the apoptotic activity of DzNep might not be directly due to its inhibition of SAHH.
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Copper-catalyzed intramolecular carbotrifluoromethylation of alkynes for the construction of trifluoromethylated heterocycles.
Chemistry
PUBLISHED: 07-13-2014
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A mild and efficient copper-catalyzed intramolecular carbotrifluoromethylation of alkynes has been achieved in the presence of Togni reagent as trifluoromethylating reagent. The reaction tolerates a range of substrates to give a group of trifluoromethylated heterocycles with high selectivities. A plausible mechanism was proposed on the basis of experimental results.
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Formula Optimization of the Jiashitang Scar Removal Ointment and Antiinflammatory Compounds Screening by NF-?B Bioactivity-guided Dual-luciferase Reporter Assay System.
Phytother Res
PUBLISHED: 07-09-2014
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Inflammation plays a role in scar formation; therefore, decreasing inflammation benefits scar removal. Jiashitang scar removal ointment (JST) is a commercially available traditional Chinese medicinal formulation. It is composed of extracts from Carthamus tinctorius L. (Car), Rheum officinale Baill. (Rhe), Salvia miltiorrhiza Beg. (Sal), and Panax notoginseng (Burk.) F.?H. Chen (Pan), which are all herbs with potent antiinflammatory activities. Our aims are to optimize the formula of JST and to elucidate its antiinflammatory active components. Response surface methodology was applied to optimize proportions of the four herb extracts. The antiinflammatory effects were evaluated using in vitro and in vivo models. To screen for active components in this formula, a bioactivity-based ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry analysis was performed. After optimization, the antiinflammatory effects of the new formula were significantly superior to the original one. Screening identified 13 active ingredients: a series of saffiomin, emodin, salvianolic acid, tanshinone, and triterpenoid saponin derivatives. These active ingredients were predicted to exert nuclear factor-?B inhibiting effects through MAPK, PI3K/AKT, and NIK-IKK pathways. In conclusion, the original formula was successfully optimized with more potent antiinflammatory activity. These methods can be applied to researches of other formulas. Copyright © 2014 John Wiley & Sons, Ltd.
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Dairy foods intake and risk of Parkinson's disease: a dose-response meta-analysis of prospective cohort studies.
Eur. J. Epidemiol.
PUBLISHED: 05-22-2014
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Dairy foods have been linked to Parkinson's disease (PD), and a meta-analysis of prospective cohort studies on dairy foods intake and PD risk was conducted. Eligible studies were identified in a literature search of EMBASE and PubMed up to April 2014. Seven results from prospective studies were included, including 1,083 PD cases among 304,193 subjects. The combined risk of PD for highest vs. lowest level of dairy foods intake was 1.40 (1.20-1.63) overall, 1.66 (1.29-2.14) for men and 1.15 (0.85-1.56) for women. For highest vs. lowest level, the PD risk was 1.45 (1.23-1.73) for milk, 1.26 (0.99-1.60) for cheese, 0.95 (0.76-1.20) for yogurt and 0.76 (0.51-1.13) for butter. The linear dose-response relationship showed that PD risk increased by 17% [1.17 (1.06-1.30)] for every 200 g/day increment in milk intake (Pfor non-linearity = 0.22), and 13% [1.13 (0.91-1.40)] for every 10 g/day increment in cheese intake (Pfor non-linearity = 0.39). The absolute risk differences were estimated to be 2-4 PD cases per 100,000 person-years for every 200 g/day increment in milk intake, and 1-3 PD cases per 100,000 person-years for every 10 g/day increment in cheese intake. Dairy foods (milk, cheese) might be positively associated with increased risk of PD, especially for men.
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MicroRNA-26a-5p and microRNA-23b-3p up-regulate peroxiredoxin III in acute myeloid leukemia.
Leuk. Lymphoma
PUBLISHED: 05-16-2014
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MicroRNAs (miRNAs) are small RNAs that regulate target gene expression. Using microarray-based miRNA expression profiling, we compared the miRNA expression in granulocytes from four patients with acute myeloid leukemia and four healthy controls. Thirty-four miRNAs were found to be differentially expressed, including 20 miRNAs that were up-regulated and 14 miRNAs that were down-regulated. The expression of selected miRNAs (miR-26a-5p and miR-23b-3p) was independently validated in 20 patients and 12 healthy controls. Notably, we demonstrated that peroxiredoxin III (PrxIII) is a common direct target of both miR-26a-5p and miR-23b-3p. Furthermore, these results indicate that the two decreased miRNAs could scavenge cellular reactive oxygen species (ROS) by targeting the PrxIII gene. These findings are discussed with regard to the known function of PrxIII as a ROS scavenger and the high endogenous ROS levels required for hematopoietic stem cell differentiation. These findings may potentially offer insights into the pathological relationships between miR-26a-5p, miR-23b-3p and leukemogenesis.
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PEDF and PEDF-derived peptide 44mer protect cardiomyocytes against hypoxia-induced apoptosis and necroptosis via anti-oxidative effect.
Sci Rep
PUBLISHED: 05-12-2014
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Pigment epithelium-derived factor (PEDF) has many biological activities. But it's not known whether PEDF and its functional peptides could protect against hypoxia-induced cell death and the mechanisms are still unclear. We used cultured H9c2 cells and primary cardiomyocytes to show that apoptosis and necroptosis were significantly increased after hypoxia. Both PEDF and its fuctional peptides 44mer reduced apoptosis and necroptosis rates and inhibited the expression of cleaved caspase 3 and receptor-interacting protein 3 (RIP3). Furthermore, PEDF and 44mer could up-regulate super oxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) levels, promote clearing of reactive oxygen species (ROS) and malondialdehyde (MDA). While, 34mer, another functional peptides had no effect on cell apoptosis and necroptosis. Hereby this is the first evidence that PEDF and its functional peptide 44mer protect cultured H9c2 cells and primary cardiomyocytes against apoptosis and necroptosis under hypoxic condition via the anti-oxidative mechanism.
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SDF-1/CXCR7 axis enhances ovarian cancer cell invasion by MMP-9 expression through p38 MAPK pathway.
DNA Cell Biol.
PUBLISHED: 05-12-2014
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Ovarian cancer is an aggressive gynecological malignancy with high metastatic potential. Recently, the CXC receptor (CXCR7) has been identified as a new receptor for stromal-derived factor-1 (SDF-1), and exerts important roles in cancer development. However, its effect on ovarian cancer and the underlying mechanism remain unknown. In this study, we detected abundant CXCR7 expression in ovarian cancer tissues and cells. Moreover, SDF-1 induced dramatically upregulation of CXCR7 mRNA and protein levels, indicating that the SDF-1/CXCR7 axis existed in ovarian cancer. Further analysis confirmed that SDF-1 enhanced cell adhesion and subsequent invasion, which were significantly attenuated when pretreated with CXCR7 small interference RNA (siRNA), indicating the critical function of SDF-1/CXCR7 in cell invasion. Further mechanistic analysis indicated that SDF-1/CXCR7 enhanced cell invasion by matrix metalloproteinase (MMP)-9, as pretreatment with MMP-9 siRNA significantly abrogated a number of invading cells. Additionally, SDF-1/CXCR7 induced phosphorylation of the p38 MAPK pathway, which was accounted for MMP-9 expression as preconditioning with the p38 MAPK inhibitor SB203580 obviously decreased MMP-9 expression. Together, our data implied that SDF-1/CXCR7 enhanced ovarian cancer cell invasion by MMP-9 expression through the p38 MAPK pathway. Thus, these findings confirmed the critical role of SDF-1/CXCR7 during the pathological processes of ovarian cancer and supported its potential targets for further development of antiovarian cancer therapy.
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Damage of hippocampal neurons in rats with chronic alcoholism.
Neural Regen Res
PUBLISHED: 05-10-2014
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Chronic alcoholism can damage the cytoskeleton and aggravate neurological deficits. However, the effect of chronic alcoholism on hippocampal neurons remains unclear. In this study, a model of chronic alcoholism was established in rats that were fed with 6% alcohol for 42 days. Endogenous hydrogen sulfide content and cystathionine-beta-synthase activity in the hippocampus of rats with chronic alcoholism were significantly increased, while F-actin expression was decreased. Hippocampal neurons in rats with chronic alcoholism appeared to have a fuzzy nuclear membrane, mitochondrial edema, and ruptured mitochondrial crista. These findings suggest that chronic alcoholism can cause learning and memory decline in rats, which may be associated with the hydrogen sulfide/cystathionine-beta-synthase system, mitochondrial damage and reduced expression of F-actin.
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Anti-CarP antibodies in two large cohorts of patients with rheumatoid arthritis and their relationship to genetic risk factors, cigarette smoking and other autoantibodies.
Ann. Rheum. Dis.
PUBLISHED: 05-08-2014
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In rheumatoid arthritis (RA), several genetic risk factors and smoking are strongly associated with the presence of anticitrullinated protein antibodies (ACPA), while much less is known about risk factors for ACPA-negative RA. Antibodies against carbamylated proteins (anti-CarP) have been described in both ACPA-positive and ACPA-negative RA patients. In this study, we have analysed the relationships among anti-CarP antibodies, ACPA, genetic risk factors (HLA-DRB1 alleles and PTPN22) and smoking in RA.
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Ablation of plasma membrane Ca(2+)-ATPase isoform 4 prevents development of hypertrophy in a model of hypertrophic cardiomyopathy.
J. Mol. Cell. Cardiol.
PUBLISHED: 04-29-2014
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The mechanisms linking the expression of sarcomeric mutant proteins to the development of pathological hypertrophy in hypertrophic cardiomyopathy (HCM) remain poorly understood. We investigated the role of the plasma membrane Ca(2+)-ATPase PMCA4 in the HCM phenotype using a transgenic model that expresses mutant (Glu180Gly) ?-tropomyosin (Tm180) in the heart. Immunoblot analysis revealed that cardiac PMCA4 expression was upregulated early in Tm180 disease pathogenesis. This was accompanied by an increase in levels of the L-type Ca(2+)-channel, which is implicated in pathological hypertrophy. When Tm180 mice were crossed with a PMCA4-null line, loss of PMCA4 caused the abrogation of hypertrophy in Tm180/PMCA4-null double mutant mice. RT-PCR analysis of Tm180/PMCA4-null hearts revealed blunting of the fetal program and reversion of pro-fibrotic Col1a1 and Col3a1 gene expression to wild-type levels. This was accompanied by evidence of reduced L-type Ca(2+)-channel expression, and diminished calcineurin activity. Expression of the metabolic substrate transporters glucose transporter 4 and carnitine palmitoyltransferase 1b was preserved and Tm180-related changes in mRNA levels of various contractile stress-related proteins including the cardiac ankyrin protein CARP and the N2B isoform of titin were reversed in Tm180/PMCA4-null hearts. cGMP levels were increased and phosphorylation of vasodilator-stimulated phosphoprotein was elevated in Tm180/PMCA4-null hearts. These changes were associated with a sharp reduction in left ventricular end-diastolic pressure in Tm180/PMCA4-null hearts, which occurred despite persistence of Tm180-related impairment of relaxation dynamics. These results reveal a novel and specific role for PMCA4 in the Tm180 hypertrophic phenotype, with the "protective" effects of PMCA4 deficiency encompassing multiple determinants of HCM-related hypertrophy.
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Functional phylogenetics reveals contributions of pleiotropic Peptide action to ligand-receptor coevolution.
Sci Rep
PUBLISHED: 04-22-2014
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The evolution of peptidergic signaling has been accompanied by a significant degree of ligand-receptor coevolution. Closely related clusters of peptide signaling molecules are observed to activate related groups of receptors, implying that genes encoding these ligands may orchestrate an array of functions, a phenomenon known as pleiotropy. Here we examine whether pleiotropic actions of peptide genes might influence ligand-receptor coevolution. Four test groups of neuropeptides characterized by conserved C-terminal amino acid sequence motifs and their cognate receptors were examined in the red flour beetle (Tribolium castaneum): 1) cardioacceleratory peptide 2b (CAPA); CAPAr, 2) pyrokinin/diapause hormone (PK1/DH); PKr-A, -B, 3) pyrokinin/pheromone biosynthesis activating hormone (PK2/PBAN); PKr-C, and 4) ecdysis triggering hormone (ETH); ETHr-b. Ligand-receptor specificities were established through heterologous expression of receptors in cell-based assays for 9 endogenous ligands. Based on ligand-receptor specificity analysis, we found positive pleiotropism exhibited by ETH on ETHR-b and CAPAr, whereas PK1/DH and CAPA are more highly selective for their respective authentic receptors than would be predicted by phylogenetic analysis. Disparities between evolutionary trees deduced from receptor sequences vs. functional ligand-receptor specificities lead to the conclusion that pleiotropy exhibited by peptide genes influences ligand-receptor coevolution.
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Contractions reverse stress softening in rat esophagus.
Ann Biomed Eng
PUBLISHED: 04-15-2014
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Strain/stress induced tissue softening is usually referred to irreversible softening. The aim of this study was to investigate whether stress softening in rat esophagus is reversible after potassium chloride (KCl) induced contraction. Three series of inflation-deflation loadings were carried out on esophageal specimens obtained from 20 Wistar rats. All specimens were subjected to the first two series in Ca(2+)-free Krebs solution(Krebs(-)) and then incubated in Ca(2+)-containing Krebs solution (Krebs(+)) for 1 h. Ten specimens were distended to pressure 1.0 kPa and activated with KCl for 3 min. The other ten specimens, however, were distended to 1.0 kPa without KCl activation. Subsequently, after incubation in Krebs(-) for 1 h, all 20 specimens were subjected to the third series testing. The stored energy in the esophageal tissues (hysteresis loop area) and the esophageal wall stiffness were compared between two groups within the three series loadings. Results indicated that incubation in Krebs(+) cannot recover the stress softening induced energy and stiffness loss, but in contrast, these loss were recovered markedly (p < 0.05) after KCl activation. In conclusion, stress softening in rat esophagus is reversible after the activation of KCl-induced contractions. This mechanism could be related to regeneration of tissue properties in rat esophagus.
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A comparative analysis of methods for predicting clinical outcomes using high-dimensional genomic datasets.
J Am Med Inform Assoc
PUBLISHED: 04-15-2014
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The objective of this investigation is to evaluate binary prediction methods for predicting disease status using high-dimensional genomic data. The central hypothesis is that the Bayesian network (BN)-based method called efficient Bayesian multivariate classifier (EBMC) will do well at this task because EBMC builds on BN-based methods that have performed well at learning epistatic interactions.
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Dairy product consumption and gastric cancer risk: A meta-analysis.
World J. Gastroenterol.
PUBLISHED: 04-02-2014
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To investigate whether dairy product consumption is a risk factor for gastric cancer.
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Improved performance of epidemiologic and genetic risk models for rheumatoid arthritis serologic phenotypes using family history.
Ann. Rheum. Dis.
PUBLISHED: 03-31-2014
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To develop and validate rheumatoid arthritis (RA) risk models based on family history, epidemiologic factors and known genetic risk factors.
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Smokeless tobacco (moist snuff) use and the risk of developing rheumatoid arthritis: results from a case-control study.
Arthritis Care Res (Hoboken)
PUBLISHED: 03-13-2014
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To investigate the association between snuff use (smokeless tobacco containing nicotine) and the risk of anti–citrullinated protein/peptide antibody (ACPA)–positive and ACPA-negative rheumatoid arthritis (RA).
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Co-expression of phosphoenolpyruvate carboxykinase and nicotinic acid phosphoribosyltransferase for succinate production in engineered Escherichia coli.
Enzyme Microb. Technol.
PUBLISHED: 02-26-2014
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Succinate is not the dominant fermentation product from xylose in wild-type Escherichia coli K12. E. coli BA 203 is a lactate dehydrogenase (ldhA), pyruvate formate lyase (pflB), and phosphoenolpyruvate (PEP)-carboxylase (ppc) deletion strain. To increase succinate accumulation and reduce byproduct formation, engineered E. coli BA204, in which ATP-forming PEP-carboxykinase (PEPCK) is overexpressed in BA203, was constructed and produced 2.17-fold higher succinate yield. To further improve the biomass and the consumption rate of xylose, nicotinic acid phosphoribosyltransferase (NAPRTase), a rate limiting enzyme in the synthesis of NAD(H), was also overexpressed. Thus, co-expression of PEPCK and NAPRTase in recombinant E. coli BA209 was investigated. In BA209, the pck gene and the pncB gene each have a trc promoter, hence, both genes are well expressed. During a 72-h anaerobic fermentation in sealed bottles, the total concentration of NAD(H) in BA209 was 1.25-fold higher than that in BA204, and the NADH/NAD+ ratio decreased from 0.28 to 0.11. During the exclusively anaerobic fermentation in a 3-L bioreactor, BA209 consumed 17.1 g L?¹ xylose and produced 15.5 g L?¹ succinate. Furthermore, anaerobic fermentation of corn stalk hydrolysate contained 30.1 g L?¹ xylose, 2.1 g L?¹ glucose and 1.5 g L?¹ arabinose, it produced a final succinate concentration of 17.2 g L?¹ with a yield of 0.94 g g?¹ total sugars.
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Association between serum level of magnesium and postmenopausal osteoporosis: a meta-analysis.
Biol Trace Elem Res
PUBLISHED: 02-24-2014
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There are conflicting reports as to the association between serum level of magnesium (Mg) and postmenopausal osteoporosis (OP). The purpose of the present study is to clarify the association between serum level of Mg and postmenopausal OP using a meta-analysis approach. We searched articles indexed in Pubmed and the Chinese Journal Full-text Database (CJFD) published as of October 2013 that met our predefined criteria. Seven eligible studies involving 1,349 postmenopausal women from 12 case-control study arms were identified. Overall, pooled analysis indicated that postmenopausal osteoporotic women had a lower serum level of Mg than the healthy controls (standardized mean difference [SMD]=-0.55, 95 % confidence interval [CI]=-0.83 to -0.26). Further subgroup analysis found a similar pattern in Turkey (SMD=-0.66, 95% CI=-0.99 to -0.32) and Belgium (SMD=-0.98, 95% CI=-1.91 to -0.05), but not in China (SMD=0.02, 95% CI=-0.21 to 0.26). And the difference of serum level of Mg between postmenopausal osteoporotic women and healthy controls below the age of 60 years (SMD=-0.61, 95% CI=-1.09 to -0.13) was similar to that among the population over 60 years (SMD=-0.49, 95% CI=-0.80 to -0.18).In conclusion, this meta-analysis suggests that the low serum level of Mg seems to be a risk factor for OP among the postmenopausal women. However, the subgroup analysis found that there was contradiction regarding races and geography, like China and Turkey. Thus, this finding needs further confirmation by trans-regional multicenter study to obtain better understanding of causal relationships between serum Mg and postmenopausal OP.
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Concentration dependence of optical clearing on the enhancement of laser-scanning optical-resolution photoacoustic microscopy imaging.
J Biomed Opt
PUBLISHED: 02-18-2014
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Quantitative analysis of optical clearing effects (OCE) induced by hyperosmotic agents is very important to optical tissue clearing applications in biomedical diagnostic imaging and therapeutics. This study aims at investigating the effect of glycerol concentration on the laser-scanning optical-resolution photoacoustic microscopy (LSOR-PAM) imaging contrast and light penetration depth. The photoacoustic (PA) signal amplitude changes are evaluated as a function of the concentration of glycerol. The results reveal that the PA signal amplitudes are enhanced with the glycerol concentration increasing, and also show that higher concentration of glycerol produces better light penetration and OCE on a phantom. The PA signal amplitude increases only 8.1% for 20% glycerol, but for higher concentrations, the increases are 76% and 165% for 40% and 60% glycerol, respectively. This preliminary study demonstrates that application of glycerol as an optical contrast agent reduces the tissue scattering and is beneficial to PAM imaging and optical diagnosis in clinical dermatology.
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Stable cell line of human SH-SY5Y uniformly expressing TWIK-related acid-sensitive potassium channel and eGFP fusion.
Appl. Biochem. Biotechnol.
PUBLISHED: 01-29-2014
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TWIK-related acid-sensitive potassium channels (TASK3) are pharmacological targets of CNS inflammation induced by acidification. They function as molecular switches between survival and death of neurons. In this report, TASK3 cloned from human brain cDNA was tagged with enhanced green fluorescent protein (eGFP), and the fusion gene was transiently expressed in human neuroblastoma SH-SY5Y cells. A cell line stably expressing TASK-eGFP fusion proteins was generated from transient expression cells by using fluorescence-activated cell sorting followed by antibiotic selection. The uniform expression of TASK3 fusion proteins was further confirmed by flow cytometry. Moreover, the localization of TASK3 tagged with eGFP was checked by confocal microcopy. TASK3-eGFP fusion proteins are observed on the SH-SY5Y cell membrane. The strategies using eGFP as a fusion tag facilitate the monitoring of the TASK3 expression and enable the successful employment of FACS for screening and construction of cell lines stably expressing TASK3. The TASK3 overexpression cell line will lay a fundamental for the in vitro evaluation of TASK3 function during hypoxic/ischemic injury.
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A two-enzyme immobilization approach using carbon nanotubes/silica as support.
Biotechnol. Prog.
PUBLISHED: 01-28-2014
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Multiple enzyme mixtures are attractive for the production of many compounds at an industrial level. We report a practical and novel approach for coimmobilization of two enzymes. The system consists of a silica microsphere core coated with two layers of individually immobilized enzymes. The model enzymes ?-amylase (AA) and glucoamylase (GluA) were individually immobilized on carbon nanotubes (CNTs). A CNT-GluA layer was formed by adsorbing CNT-GluA onto silica microsphere. A sol-gel layer with entrapped CNT-AA was then formed outside the CNT-GluA/silica microsphere conjugate. The coimmobilized ?-amylase and glucoamylase exhibited 95.1% of the activity of the mixture of free ?-amylase and glucoamylase. The consecutive use exhibited a good stability of the coimmobilized enzymes. The developed approach demonstrates advantages, including controlling the ratio of coimmobilized enzymes in an easy way, facilitating diffusion of small molecules in and out of the matrix, and preventing the leaching of enzymes. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 2014.
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The central role of EED in the orchestration of polycomb group complexes.
Nat Commun
PUBLISHED: 01-25-2014
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Polycomb repressive complexes 1 and 2 (PRC1 and 2) play a critical role in the epigenetic regulation of transcription during cellular differentiation, stem cell pluripotency and neoplastic progression. Here we show that the polycomb group protein EED, a core component of PRC2, physically interacts with and functions as part of PRC1. Components of PRC1 and PRC2 compete for EED binding. EED functions to recruit PRC1 to H3K27me3 loci and enhances PRC1-mediated H2A ubiquitin E3 ligase activity. Taken together, we suggest an integral role for EED as an epigenetic exchange factor coordinating the activities of PRC1 and 2.
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The incidence and distribution of surgical site infection in mainland china: a meta-analysis of 84 prospective observational studies.
Sci Rep
PUBLISHED: 01-22-2014
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Surgical site infection (SSI) is one of the most common surgical complications in the world, particularly in developing countries. This study aimed to estimate the incidence and distribution of SSI in mainland China. Eighty-four prospective observational studies (82 surveillance studies, 1 nested case control study, and 1 cohort study) were selected for inclusion in this meta-analysis. The average incidence of SSI in mainland China was 4.5% (95% CI: 3.1-5.8) from 2001 to 2012 and has decreased significantly in recent years. The remote western regions had a higher incidence of 4.6% (95% CI: 4.0-5.3). The most common surgical procedure was abdominal surgery (8.3%, 95% CI: 6.5-10.0). SSI occurred frequently in the elderly (5.1%, 95% CI: 2.2-8.0), patients confined to hospital for over 2 weeks (5.7%, 95% CI: 0.9-10.0), superficial incision wounds (5.6%, 95% CI: 4.4-6.8), dirty wounds (8.7%, 95% CI: 6.9-10.6), operations lasting for over 2?hours (7.3%, 95% CI: 4.9-9.7), general anaesthesia operations (4.7%, 95% CI: 2.7-6.6), emergency surgeries (5.9%, 95% CI: 4.2-7.7), and non-intra-medication operations (7.4%, 95% CI: 1.0-13.7).
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Succinic acid production from hemicellulose hydrolysate by an Escherichia coli mutant obtained by atmospheric and room temperature plasma and adaptive evolution.
Enzyme Microb. Technol.
PUBLISHED: 01-20-2014
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Atmospheric and room temperature plasma and adaptive evolution were combined to generate Escherichia coli mutants, which can simultaneously and efficiently utilize glucose and xylose to produce succinic acid in chemically defined medium under exclusively anaerobic condition. Compared to the parent strain BA305, a pflB, ldhA, ppc, and ptsG deletion strain overexpressing ATP-forming phosphoenolpyruvate (PEP) carboxykinase (PEPCK), the sugar consumption rate and succinic acid productivity of mutant BA408 were significantly improved with a marked increase in the key enzyme activities. Subsequent anaerobic fermentation of BA408 with corn stalk hydrolysate produced a final succinic acid concentration of 23.1 g L(-1) with a yield of 0.85 g g(-1) sugar mixture. The observed synthesis of succinic acid from the corn stalk hydrolysate showed a great potential usage of renewable biomass as a feedstock for an economical succinic acid production using E. coli.
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Androgen receptor signaling in hepatocellular carcinoma and pancreatic cancers.
World J. Gastroenterol.
PUBLISHED: 01-17-2014
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Hepatocellular carcinoma (HCC) and pancreatic cancer remain difficult to treat, and despite the ongoing development of new treatments, the overall survival rate has only modestly improved over the past decade. Liver and pancreatic progenitors commonly develop from endoderm cells in the embryonic foregut. A previous study showed that HCC and pancreatic cancer cell lines variably express androgen receptor (AR), and these cancers and the surrounding tissues also express AR. AR is a ligand-dependent transcription factor that belongs to the nuclear receptor superfamily. Androgen response element is present in regulatory elements on the AR-responsive target genes, such as transforming growth factor beta-1 (TGF beta-1) and vascular endothelial growth factor (VEGF). It is well known that the activation of AR is associated with human carcinogenesis in prostate cancer as well as HCC and pancreatic cancer and that GRP78, TGF beta, and VEGF all play important roles in carcinogenesis and cancer development in these cancers. HCC is a male-dominant cancer irrespective of its etiology. Previous work has reported that vertebrae forkhead box A 1/2 are involved in estrogen receptors and/or AR signaling pathways, which may contribute to the gender differences observed with HCC. Our recent work also showed that AR has a critical role in pancreatic cancer development, despite pancreatic cancer not being a male dominant cancer. Aryl hydrocarbon (or dioxin) receptor is also involved in both HCC and pancreatic cancer through the formation of complex with AR. It is possible that AR might be involved in their carcinogenesis through major histocompatibility complex class?I?chain-related gene A/B. This review article describes AR and its role in HCC and pancreatic cancer and suggests that more specific AR signaling-inhibitors may be useful in the treatment of these "difficult to treat" cancers.
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Prognostic value of p16 promoter hypermethylation in colorectal cancer: a meta-analysis.
Cancer Invest.
PUBLISHED: 01-10-2014
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Whether or not p16 promoter hypermethylation has any prognostic value on the survival of patients with colorectal cancer (CRC) is uncertain. A meta-analysis was therefore conducted on the overall survival involving 16 studies with 3968 patients and disease-free survival involving six studies with 1091 cases, respectively. The promoter hypermethylation was found to be significantly associated with shorter survival compared to controls, which was not only stable according to influence analysis and cumulative meta-analysis but also conclusive according to trial sequential meta-analysis. The meta-analysis supports the hypermethylation as an independent adverse prognostic factor for CRC.
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Involvement of androgen receptor and glucose-regulated protein 78 kDa in human hepatocarcinogenesis.
Exp. Cell Res.
PUBLISHED: 01-09-2014
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Previous studies demonstrated that androgen receptor (AR) is expressed in human hepatocellular carcinoma (HCC), one of the male-dominant diseases. Glucose-regulated protein 78 kDa (GRP78/Bip), which has a role in cancer development, is one of the androgen response genes in prostate cell lines. The aim of this study was to investigate the impact of AR on endoplasmic reticulum (ER)-stress signaling in human hepatoma. AR and GRP78 expressions were examined in human liver tissue panels. Human hepatoma cells stably expressing short hairpin RNA targeting AR and cells over-expressing AR were generated. The expressions of ER-stress molecules and AR were measured by real-time RT-PCR and Western blotting. The effect of AR on ER-stress responsive gene expression was examined by reporter assay. Strong positive correlation between AR mRNA and GRP78 mRNA was observed in stage I/II-HCCs. AR enhanced ER-stress responsive element activities and GRP78 expression, and regulated ER-stress response in hepatocytes. Sorafenib strongly induced significant apoptosis in HepG2 cells by the inhibition of AR and inhibition of the downstream GRP78. AR seems a co-regulator of GRP78 especially in earlier-stage HCC. AR plays a critical role in controlling ER-stress, providing new therapeutic options against HCC.
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Succinic acid production from sucrose by Actinobacillus succinogenes NJ113.
Bioresour. Technol.
PUBLISHED: 01-08-2014
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In this study, sucrose, a reproducible disaccharide extracted from plants, was used as the carbon source for the production of succinic acid by Actinobacillus succinogenes NJ113. During serum bottle fermentation, the succinic acid concentration reached 57.1g/L with a yield of 71.5%. Further analysis of the sucrose utilization pathways revealed that sucrose was transported and utilized via a sucrose phosphotransferase system, sucrose-6-phosphate hydrolase, and a fructose PTS. Compared to glucose utilization in single pathway, more pathways of A. succinogenes NJ113 are dependent on sucrose utilization. By changing the control strategy in a fed-batch culture to alleviate sucrose inhibition, 60.5g/L of succinic acid was accumulated with a yield of 82.9%, and the productivity increased by 35.2%, reaching 2.16g/L/h. Thus utilization of sucrose has considerable potential economics and environmental meaning.
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Downregulation of microRNA-431 by human interferon-? inhibits viability of medulloblastoma and glioblastoma cells via upregulation of SOCS6.
Int. J. Oncol.
PUBLISHED: 01-07-2014
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miRNAs are small non-coding RNAs that inhibit gene expression by cleaving or hindering the translation of target mRNAs. In this study, we focused on miR-431, which mediated inhibition of cell viability by human interferon-? (HuIFN-?). We aimed to demonstrate an antineoplastic effect of HuIFN-? via miR-431 expression against medulloblastoma and glioblastoma, because HuIFN-? is frequently used in adjuvant therapy of these tumors. Addition of HuIFN-? to medulloblastoma and glioblastoma cells reduced viability, significantly decreased miR-431 expression, upregulated expression of SOCS6 (putative miR-431 target genes) and inhibited Janus kinase (JAK) 1 and signal transducer and activator of transcription (STAT) 2. The mitogen-activated protein kinase (MAPK) pathway, but not the phosphoinositide 3-kinase (PI3K)-Akt pathway, was downregulated in medulloblastoma cells, whereas the PI3K-Akt pathway, but not the MAPK pathway, was downregulated in glioblastoma cells. Addition of HuIFN-? and transient transfection with miR-431 to medulloblastoma and glioblastoma cells did not reduce viability, downregulated expression of SOCS6, and concomitantly activated the JAK1 and STAT2. We propose that, in medulloblastoma and glioblastoma cells, HuIFN-? decreases miR-431 expression and upregulates SOCS6 expression, and consequently inhibit cell proliferation by suppressing the JAK-STAT signaling pathway.
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Regulation of microRNA by hepatitis B virus infection and their possible association with control of innate immunity.
World J. Gastroenterol.
PUBLISHED: 01-03-2014
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Hepatitis B virus (HBV) chronically infects more than 350 million people worldwide. HBV causes acute and chronic hepatitis, and is one of the major causes of cirrhosis and hepatocellular carcinoma. There exist complex interactions between HBV and the immune system including adaptive and innate immunity. Toll-like receptors (TLRs) and TLR-signaling pathways are important parts of the innate immune response in HBV infections. It is well known that TLR-ligands could suppress HBV replication and that TLRs play important roles in anti-viral defense. Previous immunological studies demonstrated that HBV e antigen (HBeAg) is more efficient at eliciting T-cell tolerance, including production of specific cytokines IL-2 and interferon gamma, than HBV core antigen. HBeAg downregulates cytokine production in hepatocytes by the inhibition of MAPK or NF-?B activation through the interaction with receptor-interacting serine/threonine protein kinase. MicroRNAs (miRNAs) are also able to regulate various biological processes such as the innate immune response. When the expressions of approximately 1000 miRNAs were compared between human hepatoma cells HepG2 and HepG2.2.15, which could produce HBV virion that infects chimpanzees, using real-time RT-PCR, we observed several different expression levels in miRNAs related to TLRs. Although we and others have shown that HBV modulates the host immune response, several of the miRNAs seem to be involved in the TLR signaling pathways. The possibility that alteration of these miRNAs during HBV infection might play a critical role in innate immunity against HBV infection should be considered. This article is intended to comprehensively review the association between HBV and innate immunity, and to discuss the role of miRNAs in the innate immune response to HBV infection.
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Emissions of ammonia and greenhouse gases during combined pre-composting and vermicomposting of duck manure.
Waste Manag
PUBLISHED: 01-03-2014
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Combined pre-composting and vermicomposting has shown potential for reclamation of solid wastes, which is a significant source of ammonia (NH3), and greenhouse gases (GHG), including nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2). Earthworms and amendments may both affect physico-chemical characteristics that control gas-producing processes, and thus affect NH3 and GHG emissions. Here, we used two-way ANOVA to test the effects of addition of reed straw and combined addition of reed straw and zeolite on NH3 and GHG emissions during pre-composting of duck manure, either with or without a follow-up phase of vermicomposting. Results showed that cumulative N2O, CH4, and CO2 emissions during pre-composting and vermicomposting ranged from 92.8, 5.8, and 260.6 mg kg(-)(1) DM to 274.2, 30.4, and 314.0 mg kg(-1) DM, respectively. Earthworms and amendments significantly decreased N2O and CH4 emissions. Emission of CO2 was not affected by earthworms, but increased in responses to addition of reed straw. Cumulative NH3 emission ranged from 3.0 to 8.1 g kg(-1) DM, and was significantly decreased by reed straw and zeolite addition. In conclusion, combined pre-composting and vermicomposting with reed straw and zeolite addition would be strongly recommended in mitigating emissions of N2O, CH4, and NH3 from duck manure. Moreover, this method also provides nutrient-rich products that can be used as a fertilizer.
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Human RAD6 Promotes G1-S Transition and Cell Proliferation through Upregulation of Cyclin D1 Expression.
PLoS ONE
PUBLISHED: 01-01-2014
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Protein ubiquitinylation regulates protein stability and activity. RAD6, an E2 ubiquitin-conjugating enzyme, which that has been substantially biochemically characterized, functions in a number of biologically relevant pathways, including cell cycle progression. In this study, we show that RAD6 promotes the G1-S transition and cell proliferation by regulating the expression of cyclin D1 (CCND1) in human cells. Furthermore, our data indicate that RAD6 influences the transcription of CCND1 by increasing monoubiquitinylation of histone H2B and trimethylation of H3K4 in the CCND1 promoter region. Our study presents, for the first time, an evidence for the function of RAD6 in cell cycle progression and cell proliferation in human cells, raising the possibility that RAD6 could be a new target for molecular diagnosis and prognosis in cancer therapeutics.
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Hepatitis C Virus Nonstructural Protein 5A Inhibits Thapsigargin-Induced Apoptosis.
PLoS ONE
PUBLISHED: 01-01-2014
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We previously reported that the hepatitis C virus (HCV) nonstructural protein 5A (NS5A) down-regulates TLR4 signaling and lipopolysaccharide-induced apoptosis of hepatocytes. There have been several reports regarding the association between HCV infection and endoplasmic reticulum (ER) stress. Here, we examined the regulation of HCV NS5A on the apoptosis of hepatocytes induced by thapsigargin, an inducer of ER stress.
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Evaluation of Outbreak Detection Performance Using Multi-Stream Syndromic Surveillance for Influenza-Like Illness in Rural Hubei Province, China: A Temporal Simulation Model Based on Healthcare-Seeking Behaviors.
PLoS ONE
PUBLISHED: 01-01-2014
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Syndromic surveillance promotes the early detection of diseases outbreaks. Although syndromic surveillance has increased in developing countries, performance on outbreak detection, particularly in cases of multi-stream surveillance, has scarcely been evaluated in rural areas.
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Searching for synergistic bronchodilators and novel therapeutic regimens for chronic lung diseases from a traditional chinese medicine, qingfei xiaoyan wan.
PLoS ONE
PUBLISHED: 01-01-2014
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Classical Chinese pharmacopeias describe numerous excellent herbal formulations, and each prescription is an outstanding pool of effective compounds for drug discovery. Clarifying the bioactivity of the combined mechanisms of the ingredients in complex traditional Chinese medicine formulas is challenging. A classical formula known as Qingfei Xiaoyan Wan, used clinically as a treatment for prevalent chronic lung disease, was investigated in this work. A mutually enhanced bioactivity-guided ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) characterization system was proposed, coupled with a dual-luciferase reporter assay for ?2AR-agonist cofactor screening. Arctiin, arctigenin, descurainoside and descurainolide B, four lignin compounds that showed synergistic bronchodilation effects with ephedrine, were revealed. The synergistic mechanism of arctigenin with the ?2ARagonist involved with the reduction of free Ca2+ was clarified by a dual-luciferase reporter assay for intracellular calcium and the Ca2+ indicator fluo-4/AM to monitor changes in the fluorescence. The relaxant and contractile responses of airway smooth muscle are regulated by crosstalk between the intracellular cAMP and calcium signaling pathways. Our data indicated the non-selective ?AR agonist ephedrine as the principal bronchodilator of the formula, whereas the lignin ingredients served as adjuvant ingredients. A greater understanding of the mechanisms governing the control of these pathways, based on conventional wisdom, could lead to the identification of novel therapeutic targets or new agents for the treatment of asthma and COPD.
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Modeling signal transduction from protein phosphorylation to gene expression.
Cancer Inform
PUBLISHED: 01-01-2014
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Signaling networks are of great importance for us to understand the cell's regulatory mechanism. The rise of large-scale genomic and proteomic data, and prior biological knowledge has paved the way for the reconstruction and discovery of novel signaling pathways in a data-driven manner. In this study, we investigate computational methods that integrate proteomics and transcriptomic data to identify signaling pathways transmitting signals in response to specific stimuli. Such methods can be applied to cancer genomic data to infer perturbed signaling pathways.
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Inferring Aberrant Signal Transduction Pathways in Ovarian Cancer from TCGA Data.
Cancer Inform
PUBLISHED: 01-01-2014
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This paper concerns a new method for identifying aberrant signal transduction pathways (STPs) in cancer using case/control gene expression-level datasets, and applying that method and an existing method to an ovarian carcinoma dataset. Both methods identify STPs that are plausibly linked to all cancers based on current knowledge. Thus, the paper is most appropriate for the cancer informatics community. Our hypothesis is that STPs that are altered in tumorous tissue can be identified by applying a new Bayesian network (BN)-based method (causal analysis of STP aberration (CASA)) and an existing method (signaling pathway impact analysis (SPIA)) to the cancer genome atlas (TCGA) gene expression-level datasets. To test this hypothesis, we analyzed 20 cancer-related STPs and 6 randomly chosen STPs using the 591 cases in the TCGA ovarian carcinoma dataset, and the 102 controls in all 5 TCGA cancer datasets. We identified all the genes related to each of the 26 pathways, and developed separate gene expression datasets for each pathway. The results of the two methods were highly correlated. Furthermore, many of the STPs that ranked highest according to both methods are plausibly linked to all cancers based on current knowledge. Finally, CASA ranked the cancer-related STPs over the randomly selected STPs at a significance level below 0.05 (P = 0.047), but SPIA did not (P = 0.083).
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Development of a surface plasmon resonance biosensing approach for the rapid detection of porcine circovirus type2 in sample solutions.
PLoS ONE
PUBLISHED: 01-01-2014
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A sensitive and label-free analytical approach for the detection of porcine circovirus type 2 (PCV2) instead of PCV2 antibody in serum sample was systematically investigated in this research based on surface plasmon resonance (SPR) with an establishment of special molecular identification membrane. The experimental device for constructing the biosensing analyzer is composed of an integrated biosensor, a home-made microfluidic module, and an electrical control circuit incorporated with a photoelectric converter. In order to detect the PCV2 using the surface plasmon resonance immunoassay, the mercaptopropionic acid has been used to bind the Au film in advance through the known form of the strong S-Au covalent bonds formed by the chemical radical of the mercaptopropionic acid and the Au film. PCV2 antibodies were bonded with the mercaptopropionic acid by covalent -CO-NH- amide bonding. For the purpose of evaluating the performance of this approach, the known concentrations of PCV2 Cap protein of 10 µg/mL, 7.5 µg/mL, 5 µg/mL, 2.5 µg/mL, 1 µg/mL, and 0.5 µg/mL were prepared by diluting with PBS successively and then the delta response units (?RUs) were measured individually. Using the data collected from the linear CCD array, the ?RUs gave a linear response over a wide concentration range of standard known concentrations of PCV2 Cap protein with the R-Squared value of 0.99625. The theoretical limit of detection was calculated to be 0.04 µg/mL for the surface plasmon resonance biosensing approach. Correspondingly, the recovery rate ranged from 81.0% to 89.3% was obtained. In contrast to the PCV2 detection kits, this surface plasmon resonance biosensing system was validated through linearity, precision and recovery, which demonstrated that the surface plasmon resonance immunoassay is reliable and robust. It was concluded that the detection method which is associated with biomembrane properties is expected to contribute much to determine the PCV2 in sample solutions instead of PCV2 antibody in serum samples quantitatively.
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Mucosal Healing Did Not Predict Sustained Clinical Remission in Patients with IBD after Discontinuation of One-Year Infliximab Therapy.
PLoS ONE
PUBLISHED: 01-01-2014
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To assess the endoscopic activity and Clinical activity after a one-year period of infliximab therapy and to evaluate the association between mucosal healing and need for retreatment after stopping infliximab in patients with Inflammatory bowel disease (IBD).
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Estimating the effectiveness of early control measures through school absenteeism surveillance in observed outbreaks at rural schools in Hubei, China.
PLoS ONE
PUBLISHED: 01-01-2014
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School absenteeism is a common data source in syndromic surveillance, which allows for the detection of outbreaks at an early stage. Previous studies focused on its correlation with other data sources. In this study, we evaluated the effectiveness of control measures based on early warning signals from school absenteeism surveillance in rural Chinese schools.
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Suppression of La antigen exerts potential antiviral effects against hepatitis A virus.
PLoS ONE
PUBLISHED: 01-01-2014
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Despite the development and availability of hepatitis A virus (HAV) vaccine, HAV infection is still a major cause of acute hepatitis that occasionally leads to fatal liver disease. HAV internal ribosomal entry-site (IRES) is one of the attractive targets of antiviral agents against HAV. The aim of the present study is to evaluate the impact of La, one of the cellular proteins, on HAV IRES-mediated translation and HAV replication.
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Modeling the altered expression levels of genes on signaling pathways in tumors as causal bayesian networks.
Cancer Inform
PUBLISHED: 01-01-2014
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This paper concerns a study indicating that the expression levels of genes in signaling pathways can be modeled using a causal Bayesian network (BN) that is altered in tumorous tissue. These results open up promising areas of future research that can help identify driver genes and therapeutic targets. So, it is most appropriate for the cancer informatics community. Our central hypothesis is that the expression levels of genes that code for proteins on a signal transduction network (STP) are causally related and that this causal structure is altered when the STP is involved in cancer. To test this hypothesis, we analyzed 5 STPs associated with breast cancer, 7 STPs associated with other cancers, and 10 randomly chosen pathways, using a breast cancer gene expression level dataset containing 529 cases and 61 controls. We identified all the genes related to each of the 22 pathways and developed separate gene expression datasets for each pathway. We obtained significant results indicating that the causal structure of the expression levels of genes coding for proteins on STPs, which are believed to be implicated in both breast cancer and in all cancers, is more altered in the cases relative to the controls than the causal structure of the randomly chosen pathways.
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Occurrence and Recurrence of Hepatocellular Carcinoma Were Not Rare Events during Phlebotomy in Older Hepatitis C Virus-Infected Patients.
Case Rep Oncol
PUBLISHED: 01-01-2014
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The use of phlebotomy is relatively common for 'difficult-to-treat by antiviral therapies' hepatitis C virus (HCV)-infected patients and for certain patients having chronic liver diseases with an iron overload of the liver. In the present study, we retrospectively analyzed patients treated with phlebotomy and their adverse events. We observed the occurrence and recurrence of hepatocellular carcinoma, and the appearance of ascites in some patients infected with HCV as well as the reduction of serum ferritin and alanine aminotransferase levels. Severe adverse events necessitating a cessation of phlebotomy occurred independently of ?-fetoprotein (>10 ng/ml) in patients infected with HCV according to multivariate logistic regression analysis. These findings may serve as a basis for phlebotomy especially in older patients with chronic hepatitis C.
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Application of a new hybrid model with seasonal auto-regressive integrated moving average (ARIMA) and nonlinear auto-regressive neural network (NARNN) in forecasting incidence cases of HFMD in Shenzhen, China.
PLoS ONE
PUBLISHED: 01-01-2014
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Outbreaks of hand-foot-mouth disease (HFMD) have been reported for many times in Asia during the last decades. This emerging disease has drawn worldwide attention and vigilance. Nowadays, the prevention and control of HFMD has become an imperative issue in China. Early detection and response will be helpful before it happening, using modern information technology during the epidemic.
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A new method for predicting patient survivorship using efficient bayesian network learning.
Cancer Inform
PUBLISHED: 01-01-2014
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The purpose of this investigation is to develop and evaluate a new Bayesian network (BN)-based patient survivorship prediction method. The central hypothesis is that the method predicts patient survivorship well, while having the capability to handle high-dimensional data and be incorporated into a clinical decision support system (CDSS). We have developed EBMC_Survivorship (EBMC_S), which predicts survivorship for each year individually. EBMC_S is based on the EBMC BN algorithm, which has been shown to handle high-dimensional data. BNs have excellent architecture for decision support systems. In this study, we evaluate EBMC_S using the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) dataset, which concerns breast tumors. A 5-fold cross-validation study indicates that EMBC_S performs better than the Cox proportional hazard model and is comparable to the random survival forest method. We show that EBMC_S provides additional information such as sensitivity analyses, which covariates predict each year, and yearly areas under the ROC curve (AUROCs). We conclude that our investigation supports the central hypothesis.
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Ultra-deep sequencing analysis of the hepatitis A virus 5'-untranslated region among cases of the same outbreak from a single source.
Int J Med Sci
PUBLISHED: 01-01-2014
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Hepatitis A virus (HAV) is a causative agent of acute viral hepatitis for which an effective vaccine has been developed. Here we describe ultra-deep pyrosequences (UDPSs) of HAV 5'-untranslated region (5'UTR) among cases of the same outbreak, which arose from a single source, associated with a revolving sushi bar. We determined the reference sequence from HAV-derived clone from an attendant by the Sanger method. Sixteen UDPSs from this outbreak and one from another sporadic case were compared with this reference. Nucleotide errors yielded a UDPS error rate of < 1%. This study confirmed that nucleotide substitutions of this region are transition mutations in outbreak cases, that insertion was observed only in non-severe cases, and that these nucleotide substitutions were different from those of the sporadic case. Analysis of UDPSs detected low-prevalence HAV variations in 5'UTR, but no specific mutations associated with severity in these outbreak cases. To our surprise, HAV strains in this outbreak conserved HAV IRES sequence even if we performed analysis of UDPSs. UDPS analysis of HAV 5'UTR gave us no association between the disease severity of hepatitis A and HAV 5'UTR substitutions. It might be more interesting to perform ultra-deep sequencing of full length HAV genome in order to reveal possible unknown genomic determinants associated with disease severity. Further studies will be needed.
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An integrated strategy of ultra-high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry and virtual screening for the identification of ?-glucosidase inhibitors in acarviostatin-containing complex.
J Chromatogr A
PUBLISHED: 12-31-2013
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We propose a strategy that integrates ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC/Q-TOF-MS) and virtual docking to identify inhibitors of multiple human -glucosidases. UPLC yielded AIB656, an acarviostatin-containing complex, which was analyzed by Q-TOF-MS to acquire structural information and was tested for inhibition of N-terminal (MGAM-N), C-terminal (MGAM-C) catalytic domain of maltase-glucoamylase, and human pancreatic -amylase (HPA).A systematic computational study was performed to evaluate the inhibition activity for 51 identified acarviostatins with various sizes, including trace or difficult-to-prepare ingredients. We evaluated the selectivities of three -glucosidases to acarviostatins and revealed the strong inhibition of MGAM-Nby acarviostatin I0-1. The high accuracy of the dual-screening was validated using enzyme inhibition assays, and docking was suggested as a possible mechanism for the strong inhibition of MGAM-N by acarviostatin I0-1 and of MGAM-C by acarbose (acarviostatin I01). No compound in AIB656 was suitable for inhibiting all three -glucosidases. Compared with conventional chromatographic separation and inhibitory activity detection, integrating UPLC/Q-TOF-MS identification and virtual validation was more convenient and more reliable. This strategy clearly demonstrates that MS data-based fingerprinting is a meaningful tool not only in identifying constituents in complex matrix but also in directly screening for powerful trace ingredients in natural products.
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Genetic risk scores and number of autoantibodies in patients with rheumatoid arthritis.
Ann. Rheum. Dis.
PUBLISHED: 12-17-2013
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Certain HLA-DRB1 alleles and single-nucleotide polymorphisms (SNPs) are associated with rheumatoid arthritis (RA). Our objective was to examine the combined effect of these associated variants, calculated as a cumulative genetic risk score (GRS) on RA predisposition, as well as the number of autoantibodies (none, one or two present).
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[Heavy metal speciation and stability in the sediment of Lihu Lake].
Huan Jing Ke Xue
PUBLISHED: 12-03-2013
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The spatial occurrence characteristics of the speciation of Cr, Ni, Cu, Zn, As, Cd, Hg and Pb in sediments of the lake body and river mouths of Lihu Lake were studied. Meanwhile, combined with the spatial distribution of metals in interstitial water, the stability and bio-availability of various forms of studied metals were discussed. The results showed that metals in interstitial water and extractable metals in surface sediments both had obvious spatial heterogeneity, and the metal contents in retreated fishery district were lower. High value areas of Cr, Cu and Zn distributed in belt along Baojie Bridge and Lihu Lake Bridge, and the high value areas of Ni, As, Cd, Hg distributed in sector extending from river mouths to the lake body. Most metals mainly existed in residue state except for Cd, Cu and Ni, the extractable content of which respectively accounted for 71.02%, 54.79% and 50.62% of the total content. The stability of eight studied metals was in the order of Cr > Pb > Hg > As > Cu > Ni > Zn > Cd. Cd and Zn were unstable in most studied sites, so there was higher risk of quick desorption and release. Toxicity assessment of interstitial water showed that the tested metals would not pose acute toxicity for aquatic ecosystem, but Hg and Pb in some districts, especially in the river mouths, might pose chronic toxicity for the benthonic organisms.
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Controlled synthesis of novel Au@MIL-100(Fe) core-shell nanoparticles with enhanced catalytic performance.
Chem. Commun. (Camb.)
PUBLISHED: 10-25-2013
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A novel porous Au@MIL-100(Fe) core-shell nanocatalyst with controllable MIL-100(Fe) shell thickness has been fabricated by using a versatile step-by-step fashion. Catalytic studies show that the Au@MIL-100(Fe) nanocatalyst exhibits much higher catalytic activity than the pure Au nanoparticles, suggesting that the MIL-100(Fe) shell enhances the catalytic activity via a synergistic effect.
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Activation of sirtuin 1 attenuates cerebral ventricular streptozotocin-induced tau hyperphosphorylation and cognitive injuries in rat hippocampi.
Age (Dordr)
PUBLISHED: 10-07-2013
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Patients with diabetes in the aging population are at high risk of Alzheimers disease (AD), and reduction of sirtuin 1 (SIRT1) activity occurs simultaneously with the accumulation of hyperphosphorylated tau in the AD-affected brain. It is not clear, however, whether SIRT1 is a suitable molecular target for the treatment of AD. Here, we employed a rat model of brain insulin resistance with intracerebroventricular injection of streptozotocin (ICV-STZ; 3 mg/kg, twice with an interval of 48 h). The ICV-STZ-treated rats were administrated with resveratrol (RSV; SIRT1-specific activator) or a vehicle via intraperitoneal injection for 8 weeks (30 mg/kg, once per day). In ICV-STZ-treated rats, the levels of phosphorylated tau and phosphorylated extracellular signal-regulated kinases 1 and 2 (ERK1/2) at the hippocampi were increased significantly, whereas SIRT1 activity was decreased without change of its expression level. The capacity of spatial memory was also significantly lower in ICV-STZ-treated rats compared with age-matched control. RSV, a specific activator of SIRT1, which reversed the ICV-STZ-induced decrease in SIRT1 activity, increases in ERK1/2 phosphorylation, tau phosphorylation, and impairment of cognitive capability in rats. In conclusion, SIRT1 protects hippocampus neurons from tau hyperphosphorylation and prevents cognitive impairment induced by ICV-STZ brain insulin resistance with decreased hippocampus ERK1/2 activity.
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Molecular cloning and functional characterization of the diapause hormone receptor in the corn earworm Helicoverpa zea.
Peptides
PUBLISHED: 10-04-2013
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The diapause hormone (DH) in the heliothine moth has shown its activity in termination of pupal diapause, while the orthology in the silkworm is known to induce embryonic diapause. In the current study, we cloned the diapause hormone receptor from the corn earworm Helicoverpa zea (HzDHr) and tested its ligand specificities in a heterologous reporter system. HzDHr was expressed in Chinese Hamster Ovary (CHO) cells, which were co-transfected with the aequorin reporter, and was used to measure the ligand activities. A total of 68 chemicals, including natural DH analogs and structurally similar peptide mimetics, were tested for agonistic and antagonistic activities. Several peptide mimetics with a 2-amino-7-bromofluorene-succinoyl (2Abf-Suc) N-terminal modification showed strong agonistic activities; these mimetics included 2Abf-Suc-F[dA]PRLamide, 2Abf-Suc-F[dR]PRLamide, 2Abf-Suc-FKPRLamide and 2Abf-Suc-FGPRLamide. Antagonistic activity was found in the ecdysis triggering hormone in Drosophila melanogaster (FFLKITKNVPRLamide). Interestingly, HzDHr does not discriminate between DH (WFGPRLamide C-terminal motif) and another closely related endogenous peptide, pyrokinin 1 (FXPRXamide; a C-terminal motif that is separate from WFGPRLamide). We provide large-scale in vitro data that serve as a reference for the development of agonists and antagonists to disrupt the DH signaling pathway.
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IL-28B polymorphisms and treatment response in hepatitis C virus patients with persistently normal alanine aminotransferase.
World J Hepatol
PUBLISHED: 09-01-2013
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To examine the association between the interleukin 28B (IL-28B) genotype and treatment response in hepatitis C virus (HCV)-infected patients with persistently normal alanine aminotransferase (PNALT).
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Natalisin, a tachykinin-like signaling system, regulates sexual activity and fecundity in insects.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 08-26-2013
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An arthropod-specific peptidergic system, the neuropeptide designated here as natalisin and its receptor, was identified and investigated in three holometabolous insect species: Drosophila melanogaster, Tribolium castaneum, and Bombyx mori. In all three species, natalisin expression was observed in 3-4 pairs of the brain neurons: the anterior dorso-lateral interneurons, inferior contralateral interneurons, and small pars intercerebralis neurons. In B. mori, natalisin also was expressed in two additional pairs of contralateral interneurons in the subesophageal ganglion. Natalisin-RNAi and the activation or silencing of the neural activities in the natalisin-specific cells in D. melanogaster induced significant defects in the mating behaviors of both males and females. Knockdown of natalisin expression in T. castaneum resulted in significant reduction in the fecundity. The similarity of the natalisin C-terminal motifs to those of vertebrate tachykinins and of tachykinin-related peptides in arthropods led us to identify the natalisin receptor. A G protein-coupled receptor, previously known as tachykinin receptor 86C (also known as the neurokinin K receptor of D. melanogaster), now has been recognized as a bona fide natalisin receptor. Taken together, the taxonomic distribution pattern of the natalisin gene and the phylogeny of the receptor suggest that natalisin is an ancestral sibling of tachykinin that evolved only in the arthropod lineage.
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[Temporal-spatial distribution of algal cells during drought period in Daning River of Three Gorges].
Huan Jing Ke Xue
PUBLISHED: 08-17-2013
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In order to provide basic data for algal bloom warning system, the study on temporal-spatial distribution of algal cells was carried out in Daning River of Three Gorges form April to September, 2011. The results of temporal distribution were as follows: the dominant algal species were blue algal, green algal and diatom. During the test, the density proportion of blue algae increased continuously, the density proportion of diatom decreased, while the density proportion of green algae did not change significantly. The results of spatial distribution were as follows: algal density was extremely significantly correlated with water temperature and chlorophyll a (Chl a), the correlation coefficient were 0.97 and 0.95, respectively; algal density was significantly correlated with light intensity (LI), dissolved oxygen (DO), pH and dissoluble total phosphorus (DTP), the correlation coefficient were 0.87, 0.83, 082 and 0.82, respectively; the algal density in 0 m of Caziba was higher than those in other water depths, and in Baishuihe the highest algal density occurred at 2.0 m water depth in June and July, in Shuanglong most algal cells were found in 0 m and 2.0 m in July, August and September, in Dachang algal density in different water depth did not change significantly during the test; the proportion of different algal species in vertical direction was different in the test, probably because different algal species fitted different environments.
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A novel artificial neural network method for biomedical prediction based on matrix pseudo-inversion.
J Biomed Inform
PUBLISHED: 08-09-2013
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Biomedical prediction based on clinical and genome-wide data has become increasingly important in disease diagnosis and classification. To solve the prediction problem in an effective manner for the improvement of clinical care, we develop a novel Artificial Neural Network (ANN) method based on Matrix Pseudo-Inversion (MPI) for use in biomedical applications. The MPI-ANN is constructed as a three-layer (i.e., input, hidden, and output layers) feed-forward neural network, and the weights connecting the hidden and output layers are directly determined based on MPI without a lengthy learning iteration. The LASSO (Least Absolute Shrinkage and Selection Operator) method is also presented for comparative purposes. Single Nucleotide Polymorphism (SNP) simulated data and real breast cancer data are employed to validate the performance of the MPI-ANN method via 5-fold cross validation. Experimental results demonstrate the efficacy of the developed MPI-ANN for disease classification and prediction, in view of the significantly superior accuracy (i.e., the rate of correct predictions), as compared with LASSO. The results based on the real breast cancer data also show that the MPI-ANN has better performance than other machine learning methods (including support vector machine (SVM), logistic regression (LR), and an iterative ANN). In addition, experiments demonstrate that our MPI-ANN could be used for bio-marker selection as well.
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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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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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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.