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Find video protocols related to scientific articles indexed in Pubmed.
Cytological observation and DNA methylation analysis of two new cytoplasmic male sterile lines of maize during microsporogenesis.
Yi Chuan
PUBLISHED: 11-20-2014
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Cytoplasmic male sterility (CMS) is a widespread phenomenon in higher plants and has been applied in the commercial production of hybrid seeds. Two CMS lines A1 and A2 of maize were obtained previously by a transgenic experiment. In this study, we conducted cytological observation of developmental microspores with CMS line A1, A2 and their maintainer line (18 red) using paraffin section technology. We also analyzed DNA methylation levels at different developmental stages using high performance liquid chromatography (HPLC). Our results showed that the pollen abortion of A1 and A2 mainly happened from the tetrad stage to the middle of mononuclear stage. Another abortive phenomenon found in CMS line A2 occurred at the pollen mother cell stage. The DNA methylation level of leaf increased rapidly from the seedling stage to the shooting stage in 18 red, while it remained constant in A1 and A2. For the tassel, the DNA methylation levels in 18 red increased gradually during the anther development, while a peak of DNA methylation level occurred in A1 and A2 at the tetrad stage, corresponding to the abortion period of microspore. This result suggested that the level of DNA methylation in the tassels is associated with the pollen abortion characteristics in CMS lines. In summary, our results implied a connection between pollen abortion and epigenetic regulation in maize CMS.
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[Analysis of the Factors Associated with Abnormal Coagulation and Prognosis?in Patients with Non-small Cell Lung Cancer].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 11-19-2014
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The activation of coagulation and fibrinolysis is frequently encountered among cancer patients. Such tumors are associated with high risk of invasion, metastases, and negative final outcomes. Non-small cell lung cancer (NSCLC) accounts for approximately 80% to 85% of all lung malignancies. This study aims to investigate the prognostic value of blood coagulation tests for NSCLC and provide a reference to patients on the prevention and treatment of thrombophilia.
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[Insulin requirement profiles and related factors of type 2 diabetics with insulin pump therapy].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 11-18-2014
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To explore the insulin requirement profiles and analyze the related factors of type 2 diabetics on insulin pump therapy.
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The evolutionary history and spatiotemporal dynamics of the fever, thrombocytopenia and leukocytopenia syndrome virus (FTLSV) in China.
PLoS Negl Trop Dis
PUBLISHED: 10-01-2014
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In 2007, a novel bunyavirus was found in Henan Province, China and named fever, thrombocytopenia and leukocytopenia syndrome virus (FTLSV); since then, FTLSV has been found in ticks and animals in many Chinese provinces. Human-to-human transmission has been documented, indicating that FTLSV should be considered a potential public health threat. Determining the historical spread of FTLSV could help curtail its spread and prevent future movement of this virus.
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A scatter correction method for dual-energy digital mammography: Monte Carlo simulation.
J Xray Sci Technol
PUBLISHED: 10-01-2014
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To develop a novel scatter correction method without additional patient dose for dual-energy digital mammography (DEDM) to reduce scatter's impacts and enhance microcalcification detectability in dual-energy X-ray subtraction image.
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Systematic Review and Meta-Analysis of benefits and risks between normothermia and hypothermia during cardiopulmonary bypass in pediatric cardiac surgery.
Paediatr Anaesth
PUBLISHED: 09-26-2014
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The controversy over the benefits between normothermic and hypothermic cardiopulmonary bypass (CPB) for children is still uncertain. The purpose of this systematic review and meta-analysis is to investigate the benefits and risks of normothermia comparing with hypothermia in pediatric cardiac surgery by randomized controlled trials.
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Selenium/interconnected porous hollow carbon bubbles composites as the cathodes of Li-Se batteries with high performance.
Nanoscale
PUBLISHED: 09-19-2014
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A kind of Se/C nanocomposite is fabricated by dispersing selenium in interconnected porous hollow carbon bubbles (PHCBs) via a melt-diffusion method. Such PHCBs are composed of porous hollow carbon spheres with a size of ?70 nm and shells of ?12 nm thickness interconnected to each other. Instrumental analysis shows that the porous shell of the PHCBs could effectively disperse and sequester most of the selenium, while the inner cavity remains hollow. When evaluated as cathode materials in a carbonate-based electrolyte for Li-Se batteries, the Se/PHCBs composites exhibit significantly excellent cycling performance and a high rate capability. Especially, the Se/PHCBs composite with an optimal content of ?50 wt% selenium (Se50/PHCBs) displays a reversible discharge capacity of 606.3 mA h g(-1) after 120 cycles at 0.1 C charge-discharge rate. As the current density increased from 0.1 to 1 C (678 mA g(-1)), the reversible capacity of the Se50/PHCBs composite can still reach 64% of the theoretical capacity (431.9 mA h g(-1)). These outstanding electrochemical features should be attributed to effective sequestration of Se in the PHCBs, as well as to the ability to accommodate volume variation and enhance the electronic transport by making Se have close contact with the carbon framework.
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Viral infection of implanted meningeal tumors induces antitumor memory T-cells to travel to the brain and eliminate established tumors.
Neuro-oncology
PUBLISHED: 09-17-2014
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Leptomeningeal metastases occur in 2%-5% of patients with breast cancer and have an exceptionally poor prognosis. The blood-brain and blood-meningeal barriers severely inhibit successful chemotherapy. We have developed a straightforward method to induce antitumor memory T-cells using a Her2/neu targeted vesicular stomatitis virus. We sought to determine whether viral infection of meningeal tumor could attract antitumor memory T-cells to eradicate the tumors.
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Effects of dry method esterification of starch on the degradation characteristics of starch/polylactic acid composites.
Int. J. Biol. Macromol.
PUBLISHED: 09-03-2014
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Maleic anhydride esterified corn starch was prepared by dry method. Esterified starch/polylactic acid (PLA) biodegradable composite was produced via melt extrusion method with blending maleic anhydride esterified corn starch and PLA. The influence of the dry method esterification of starch on the degradation characteristics of starch/PLA composites was investigated by the natural aging degradation which was soil burial method. Test results of mass loss rate showed that the first 30 days of degradation was mainly starch degradation, and the degradation rate of esterified starch/PLA (ES/PLA) was slower than that of native starch/PLA (NS/PLA). Therefore, the damage degree of ES/PLA on the surface and inside was smaller than that of NS/PLA, and the infrared absorption peak intensities of CO, CO and CH were stronger than that of NS/PLA. With the increasing time of soil burial degradation, the damage degree of NS/PLA and ES/PLA on the exterior and interior were gradually increased, whereas the infrared absorption peak intensities of CO, CO and CH were gradually decreased. The XRD diffraction peak intensity of PLA in composites showed an increased trend at first which was then followed by a decreased one along with the increasing time of soil burial degradation, indicating that the degradation of amorphous regions of PLA was earlier than its crystalline regions. When the soil burial time was the same, the diffraction peak intensity of PLA in ES/PLA was stronger than that of NS/PLA. If the degradation time was the same, T0, Ti and residual rate of thermal decomposition of NS/PLA were larger than those of ES/PLA. The tensile strength and bending strength of composites were decreased gradually with soil burial time increasing. Both the tensile strength and bending strength of ES/PLA were stronger than those of NS/PLA.
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[A cohort study on the impacts of pre-pregnancy maternal body mass index, gestational weight gain on neonate birth status and perinatal outcomes in Fujian province].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 09-02-2014
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To study the impacts of pre-pregnancy maternal BMI and gestational weight gain(GWG) on pregnancy outcomes.
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miR-210 over-expression enhances mesenchymal stem cell survival in an oxidative stress environment through antioxidation and c-Met pathway activation.
Sci China Life Sci
PUBLISHED: 08-29-2014
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microRNA-210 (miR-210) has generally been reported to be associated with cell survival under hypoxia. However, there are few data regarding the role of miR-210 in the survival of mesenchymal stem cells (MSCs) under oxidative stress conditions. Thus, we sought to investigate whether miR-210 over-expression could protect MSCs against oxidative stress injury and what the primary mechanisms involved are. The results showed that over-expression of miR-210 significantly reduced the apoptosis of MSCs under oxidative stress, accompanied by obvious increases in cell viability and superoxide dismutase activity and remarkable decreases in malonaldehyde content and reactive oxygen species production, resulting in a noticeable reduction of apoptotic indices when compared with the control. Moreover, the above beneficial effects of miR-210 could be significantly reduced by c-Met pathway repression. Collectively, these results showed that miR-210 over-expression improved MSC survival under oxidative stress through antioxidation and c-Met pathway activation, indicating the potential development of a novel approach to enhance the efficacy of MSC-based therapy for injured myocardium.
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A novel molecule Me6TREN promotes angiogenesis via enhancing endothelial progenitor cell mobilization and recruitment.
Sci Rep
PUBLISHED: 08-28-2014
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Critical limb ischaemia is the most severe clinical manifestation of peripheral arterial disease. The circulating endothelial progenitor cells (EPCs) play important roles in angiogenesis and ischemic tissue repair. The increase of circulating EPC numbers by using mobilization agents is critical for obtaining a better therapeutic outcome in patients with ischemic disease. Here, we firstly report a novel small molecule, Me6TREN (Me6), can efficiently mobilize EPCs into the blood circulation. Single injection of Me6 induced a long-lasting increase in circulating Flk-1(+) Sca-1(+) EPC numbers. In a mouse hind limb ischemia (HLI) model, local intramuscular transplantation of these Me6-mobilized cells accelerated the blood flow restoration in the ischemic muscles. More importantly, systemic administration of Me6 notably increased the capillary density, arteriole density and regenerative muscle weight in the ischemic tissue of HLI. Mechanistically, we found Me6 reduced stromal cell-derived factor-1? level in bone marrow by up-regulation of matrix metallopeptidase-9 expression, which allowed the dissemination of EPCs into peripheral blood. These data indicate that Me6 may represent a potentially useful therapy for ischemic disease via enhancing autologous EPC recruitment and promote angiogenesis.
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[Analysis on GJB2 gene mutations with nonsyndromic hearing impairment in Kazak patients of Xinjiang].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 08-19-2014
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To study mutations in the GJB2 gene in Kazak patients with nonsyndromic hearing impairment from Xinjiang.
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Birth weight reference percentiles for Chinese.
PLoS ONE
PUBLISHED: 08-15-2014
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To develop a reference of population-based gestational age-specific birth weight percentiles for contemporary Chinese.
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Oligomer procyanidins (F2) isolated from grape seeds inhibits tumor angiogenesis and cell invasion by targeting HIF-1? in vitro.
Int. J. Oncol.
PUBLISHED: 08-06-2014
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Overexpression of hypoxia-inducible factor-1 (HIF-1) ?, a transcription factor which immortalizes tumors by inducing expression of the genes involved in cell survival, migration and angiogenesis, is closely associated with poor prognosis, increased risk of metastasis and increased mortality. Oligomer procyanidins (F2), a natural fraction from grape seeds, has been demonstrated to have antioxidant and antitumor activities, however the antitumor effect of F2 targeting HIF-1? remains unknown. The present study showed that F2 markedly decreased HIF-1? and the expression of its target genes in cancer cells through inactivating the EGFR-PI3K-AKT-mTOR and MAPK-ERK1/2 pathways. Moreover, F2 suppressed vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMP)-2 expressions, followed by the inhibition of tumor angiogenesis and cell invasion in a HIF-1?-dependent manner. Collectively, these findings indicate that the antitumor effect of F2 is, at least in part, mediated by suppressing HIF-1?-dependent pathway, and suggest that F2 may be a potentially useful agent for treatment of human cancer.
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The relationships between type 2 diabetic retinopathy and VEGF-634G/C and VEGF-460C/T polymorphisms in Han Chinese subjects.
J. Diabetes Complicat.
PUBLISHED: 07-27-2014
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To investigate how VEGF-634G/C and VEGF-460C/T SNPs are related to diabetic retinopathy (DR) in Han Chinese subjects from the Shijiazhuang region of China.
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miRNA-130b is required for the ERK/FOXM1 pathway activation-mediated protective effects of isosorbide dinitrate against mesenchymal stem cell senescence induced by high glucose.
Int. J. Mol. Med.
PUBLISHED: 07-15-2014
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The present study was carried out to investigate the hypothesis that organic nitrates can attenuate the senescence of mesenchymal stem cells (MSCs), a superior cell source involved in the regeneration and repair of damaged tissue. MSCs were treated with high glucose (HG) in order to induce senescence, which was markedly attenuated by pre-treatment with isosorbide dinitrate (ISDN), a commonly used nitrate, as indicated by senescence-associated galactosidase (SA-?-gal) activity, p21 expression, as well as by the mRNA levels of DNA methyltransferase 1 (DNMT1) and differentiated embryo chondrocyte expressed gene 1 (DEC1), which are senescence-related biomarkers. It was also found that the senescent MSCs (induced by HG glucose) exhibited a marked downregulation in ERK activity and forkhead box M1 (FOXM1) expression, which was reversed by ISDN preconditioning. Of note, the inhibition of ERK phosphorylation or the downregulation of FOXM1 statistically abolished the favourable effects of ISDN. In addition, the investigation of the senescence-associated miR-130 family suggested that miR-130b mediates the beneficial effects of ISDN; it was found that the protective effects of ISDN against the senescence of MSCs were prominently reversed by the knockdown of miR-130b. Furthermore, the downregulation of ERK phosphorylation or FOXM1 expression decreased the miR-130b expression level; however, the suppression of miR-130b demonstrated no significant impact on ERK phosphorylation or FOXM1 expression. Taken together, to the best of our knowledge, the present study is the first to demonstrate the favourable effects of ISDN against HG-induced MSC senescence, which are mediated through the activation of the ERK/FOXM1 pathway and the upregulation of miR-130b.
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Predictive value of early amplitude-integrated electroencephalography for later diagnosed cerebral white matter damage in preterm infants.
Neuropediatrics
PUBLISHED: 07-08-2014
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?The aim of the article is to assess the predictive value of amplitude-integrated electroencephalogram (aEEG) for cerebral white matter damage (WMD) in preterm infants. Patients and
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[Expression and activity determination of recombinant capsid protein VP2 gene of enterovirus type 71].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 06-28-2014
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To clone and express the recombinant capsid protein VP2 of enterovirus type 71 (EV71) and to identify the immune activity of expressed protein in order to build a basis for the investigation work of vaccine and diagnostic antigen.
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NK cells in the tumor microenvironment.
Crit Rev Oncog
PUBLISHED: 06-19-2014
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The presence of natural killer (NK) cells in the tumor microenvironment correlates with outcome in a variety of cancers. However, the role of intratumoral NK cells is unclear. Preclinical studies have shown that, while NK cells efficiently kill circulating tumor cells of almost any origin, they seem to have very little effect against the same type of tumor cells when these have extravasated. The ability to kill extravasated tumor cells is, however, is dependent of the level of activation of the NK cells, as more recent published and unpublished studies, discussed below, have demonstrated that interleukin-2-activated NK cells are able to attack well-established solid tumors.
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Cancer survival in China, 2003-2005: A population-based study.
Int. J. Cancer
PUBLISHED: 06-09-2014
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Limited population-based cancer registry data available in China until now has hampered efforts to inform cancer control policy. Following extensive efforts to improve the systematic cancer surveillance in this country, we report on the largest pooled analysis of cancer survival data in China to date. Of 21 population-based cancer registries, data from 17 registries (n?=?138,852 cancer records) were included in the final analysis. Cases were diagnosed in 2003-2005 and followed until the end of 2010. Age-standardized relative survival was calculated using region-specific life tables for all cancers combined and 26 individual cancers. Estimates were further stratified by sex and geographical area. The age-standardized 5-year relative survival for all cancers was 30.9% (95% confidence intervals: 30.6%-31.2%). Female breast cancer had high survival (73.0%) followed by cancers of the colorectum (47.2%), stomach (27.4%), esophagus (20.9%), with lung and liver cancer having poor survival (16.1% and 10.1%), respectively. Survival for women was generally higher than for men. Survival for rural patients was about half that of their urban counterparts for all cancers combined (21.8% vs. 39.5%); the pattern was similar for individual major cancers except esophageal cancer. The poor population survival rates in China emphasize the urgent need for government policy changes and investment to improve health services. While the causes for the striking urban-rural disparities observed are not fully understood, increasing access of health service in rural areas and providing basic health-care to the disadvantaged populations will be essential for reducing this disparity in the future.
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Phase-coexistence and thermal hysteresis in samples comprising adventitiously doped MnAs nanocrystals: programming of aggregate properties in magnetostructural nanomaterials.
ACS Nano
PUBLISHED: 06-06-2014
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Small changes in the synthesis of MnAs nanoparticles lead to materials with distinct behavior. Samples prepared by slow heating to 523 K (type-A) exhibit the characteristic magnetostructural transition from the ferromagnetic hexagonal (?) to the paramagnetic orthorhombic (?) phase of bulk MnAs at Tp = 312 K, whereas those prepared by rapid nucleation at 603 K (type-B) adopt the ? structure at room temperature and exhibit anomalous magnetic properties. The behavior of type-B nanoparticles is due to P-incorporation (up to 3%), attributed to reaction of the solvent (trioctylphosphine oxide). P-incorporation results in a decrease in the unit cell volume (?1%) and shifts Tp below room temperature. Temperature-dependent X-ray diffraction reveals a large region of phase-coexistence, up to 90 K, which may reflect small differences in Tp from particle-to-particle within the nearly monodisperse sample. The large coexistence range coupled to the thermal hysteresis results in process-dependent phase mixtures. As-prepared type-B samples exhibiting the ? structure at room temperature convert to a mixture of ? and ? after the sample has been cooled to 77 K and rewarmed to room temperature. This change is reflected in the magnetic response, which shows an increased moment and a shift in the temperature hysteresis loop after cooling. The proportion of ? present at room temperature can also be augmented by application of an external magnetic field. Both doped (type-B) and undoped (type-A) MnAs nanoparticles show significant thermal hysteresis narrowing relative to their bulk phases, suggesting that formation of nanoparticles may be an effective method to reduce thermal losses in magnetic refrigeration applications.
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Transactivation of programmed ribosomal frameshifting by a viral protein.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 05-13-2014
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Programmed -1 ribosomal frameshifting (-1 PRF) is a widely used translational mechanism facilitating the expression of two polypeptides from a single mRNA. Commonly, the ribosome interacts with an mRNA secondary structure that promotes -1 frameshifting on a homopolymeric slippery sequence. Recently, we described an unusual -2 frameshifting (-2 PRF) signal directing efficient expression of a transframe protein [nonstructural protein 2TF (nsp2TF)] of porcine reproductive and respiratory syndrome virus (PRRSV) from an alternative reading frame overlapping the viral replicase gene. Unusually, this arterivirus PRF signal lacks an obvious stimulatory RNA secondary structure, but as confirmed here, can also direct the occurrence of -1 PRF, yielding a third, truncated nsp2 variant named "nsp2N." Remarkably, we now show that both -2 and -1 PRF are transactivated by a protein factor, specifically a PRRSV replicase subunit (nsp1?). Embedded in nsp1?'s papain-like autoproteinase domain, we identified a highly conserved, putative RNA-binding motif that is critical for PRF transactivation. The minimal RNA sequence required for PRF was mapped within a 34-nt region that includes the slippery sequence and a downstream conserved CCCANCUCC motif. Interaction of nsp1? with the PRF signal was demonstrated in pull-down assays. These studies demonstrate for the first time, to our knowledge, that a protein can function as a transactivator of ribosomal frameshifting. The newly identified frameshifting determinants provide potential antiviral targets for arterivirus disease control and prevention. Moreover, protein-induced transactivation of frameshifting may be a widely used mechanism, potentially including previously undiscovered viral strategies to regulate viral gene expression and/or modulate host cell translation upon infection.
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A Sub-Element in PRE enhances nuclear export of intronless mRNAs by recruiting the TREX complex via ZC3H18.
Nucleic Acids Res.
PUBLISHED: 04-29-2014
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Viral RNA elements that facilitate mRNA export are useful tools for identifying cellular RNA export factors. Here we show that hepatitis B virus post-transcriptional element (PRE) is one such element, and using PRE several new cellular mRNA export factors were identified. We found that PRE drastically enhances the cytoplasmic accumulation of cDNA transcripts independent of any viral protein. Systematic deletion analysis revealed the existence of a 116 nt functional Sub-Element of PRE (SEP1). The RNP that forms on the SEP1 RNA was affinity purified, in which TREX components as well as several other proteins were identified. TREX components and the SEP1-associating protein ZC3H18 are required for SEP1-mediated mRNA export. Significantly, ZC3H18 directly binds to the SEP1 RNA, interacts with TREX and is required for stable association of TREX with the SEP1-containing mRNA. Requirements for SEP1-mediated mRNA export are similar to those for splicing-dependent mRNA export. Consistent with these similarities, several SEP1-interacting proteins, including ZC3H18, ARS2, Acinus and Brr2, are required for efficient nuclear export of polyA RNAs. Together, our data indicate that SEP1 enhances mRNA export by recruiting TREX via ZC3H18. The new mRNA export factors that we identified might be involved in cap- and splicing-dependent TREX recruitment to cellular mRNAs.
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Expression pattern of porcine antimicrobial peptide PR-39 and its induction by enterotoxigenic Escherichia coli (ETEC) F4ac.
Vet. Immunol. Immunopathol.
PUBLISHED: 04-27-2014
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PR-39 is a gene-encoded, proline-arginine-rich porcine antimicrobial peptide with multiple biological functions. In the current study, the tissue-specific mRNA expression of PR-39 was investigated in Chinese Jinhua pigs, and the effect of enterotoxigenic Escherichia coli (ETEC) expressing F4ac (K88ac) fimbriae challenge on the mRNA expression of PR-39 in various tissues was compared between Jinhua and Landrace pigs. The three most stable expressed housekeeping genes were validated before evaluating PR-39 expression. PR-39 mRNA was predominantly expressed in the bone marrow compared with the spleen, thymus, MLN, liver and ileum. The ETEC F4ac challenge could up-regulate PR-39 mRNA expression in both Jinhua and Landrace pigs, but the changes were different between the two breeds. Jinhua pigs responded more strongly to ETEC F4ac challenge than did Landrace pigs, because the interaction between the breed and challenge significantly impact PR-39 mRNA in the thymus, liver and ileum. The PR-39 mRNA expression levels of challenged Jinhua pigs were significantly higher in the spleen, thymus, liver, ileum and MLN compared with challenged Landrace pigs. These differences in the mRNA expression of PR-39 could be a result of genetic differences in the resistance to ETEC F4ac infection between the two breeds, but this speculation requires further investigation.
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Mutational Screening of EFNA5 in Chinese Age-Related Cataract Patients.
Ophthalmic Res.
PUBLISHED: 04-18-2014
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In the past few years, Ephrin-A5 (EFNA5) had been identified to be associated with lens development, but so far no sequence variation in EFNA5 has been reported in humans. Therefore, we conduct this study to investigate the EFNA5 genetic variations in Chinese age-related cataract (ARC) patients.
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Cyclic dipeptides produced by fungus Eupenicillium brefeldianum HMP-F96 induced extracellular alkalinization and H2O 2 production in tobacco cell suspensions.
World J. Microbiol. Biotechnol.
PUBLISHED: 04-17-2014
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Extracellular alkalinization and H2O2 production are important early events during induced systemic resistance (ISR) establishment in plants. In a screen for metabolites as potential ISR activators from 98 fungal isolates associated with marine sponge Hymeniacidon perleve, the crude metabolites of fungus Eupenicillium brefeldianum HMP-F96 induced significant extracellular alkalinization coupled with H2O2 production in tobacco cell suspensions. A combined bioactivity and (1)H NMR-guided fractionation approach was used to disclose the chemical determinants responsible for the activities. Eight cyclic dipeptides were purified from the fermentation broth of the strain and were structurally characterized by NMR and MS experiments. This study represents the first report of the occurrence of cyclic dipeptides in E. brefeldianum and of their activities of inducing extracellular alkalinization and H2O2 production in tobacco cell suspensions.
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[Effects of lipoic acid on cytokines and chemokines in astrocytes stimulated with lipopolysaccharide].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 04-12-2014
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To investigate the effects of lipoic acid (LA) on the release of TNF-?, IL-1?, IL-6, IL-10 and the expressions of chemokines in astrocytes stimulated with lipopolysaccharide (LPS).
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Congenital cataracts due to a novel 2?bp deletion in CRYBA1/A3.
Mol Med Rep
PUBLISHED: 04-11-2014
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Congenital cataracts, which are a clinically and genetically heterogeneous group of eye disorders, lead to visual impairment and are a significant cause of blindness in childhood. A major proportion of the causative mutations for congenital cataracts are found in crystallin genes. In the present study, a novel deletion mutation (c.590?591delAG) in exon 6 of CRYBA1/A3 was identified in a large family with autosomal dominant congenital cataracts. An increase in local hydrophobicity was predicted around the mutation site; however, further studies are required to determine the exact effect of the mutation on ?A1/A3?crystallin structure and function. To the best of our knowledge, this is the first report of an association between a frameshift mutation in exon 6 of CRYBA1/A3 and congenital cataracts.
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Equine arteritis virus does not induce interferon production in equine endothelial cells: identification of nonstructural protein 1 as a main interferon antagonist.
Biomed Res Int
PUBLISHED: 04-07-2014
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The objective of this study was to investigate the effect of equine arteritis virus (EAV) on type I interferon (IFN) production. Equine endothelial cells (EECs) were infected with the virulent Bucyrus strain (VBS) of EAV and expression of IFN-? was measured at mRNA and protein levels by quantitative real-time RT-PCR and IFN bioassay using vesicular stomatitis virus expressing the green fluorescence protein (VSV-GFP), respectively. Quantitative RT-PCR results showed that IFN-? mRNA levels in EECs infected with EAV VBS were not increased compared to those in mock-infected cells. Consistent with quantitative RT-PCR, Sendai virus- (SeV-) induced type I IFN production was inhibited by EAV infection. Using an IFN-? promoter-luciferase reporter assay, we subsequently demonstrated that EAV nsps 1, 2, and 11 had the capability to inhibit type I IFN activation. Of these three nsps, nsp1 exhibited the strongest inhibitory effect. Taken together, these data demonstrate that EAV has the ability to suppress the type I IFN production in EECs and nsp1 may play a critical role to subvert the equine innate immune response.
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A highly selective and instantaneous nanoprobe for detection and imaging of ascorbic acid in living cells and in vivo.
Anal. Chem.
PUBLISHED: 04-01-2014
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The development of a specific reaction of nanomaterials and reactive species is of fundamental importance for the determination of biomolecules. Here we report a novel nanoprobe for detection and imaging of ascorbic acid (AA) in living cells and in vivo based on the specific reaction of cobalt oxyhydroxide (CoOOH) and AA. Persistent luminescence nanoparticles (PLNPs) were used as the luminescence unit, and CoOOH nanoflakes served as the quencher. When CoOOH was modified on the surface of the PLNPs, the luminescence of the PLNPs was efficiently quenched by the CoOOH. In the presence of AA, CoOOH was reduced to Co(2+) and the luminescence of PLNPs was restored. The nanoprobe showed high selectivity and an instantaneous response. The luminescence property permits detection and imaging without external excitation, which could effectively avoid background noise and scattering of light from biological matrixes produced by in situ excitation. The current strategy provides an effective platform for monitoring and imaging reactive species in living cells and in vivo.
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[Study on the induction and differentiation of megakaryocyte progenitor cell derived from umbilical cord blood].
Zhonghua Xue Ye Xue Za Zhi
PUBLISHED: 03-27-2014
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To build a protocol of separation and induction of megakaryocytes derived from cord blood mononuclear cells.
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Contrast-enhanced sonography of thyroid nodules.
J Clin Ultrasound
PUBLISHED: 03-21-2014
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To investigate the value of contrast-enhanced ultrasound (CEUS) in the differentiation of benign and malignant nodules.
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[Investigation of occupational noise exposure and hearing loss in large automobile manufacturing enterprise during 2006-2010 in Guangzhou, China].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 03-18-2014
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To analyze the relationship between occupational noise exposure and hearing loss among workers in large automobile manufacturing enterprise during 2006-2010 in Guangzhou, China.
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MADS-box transcription factor SsMADS is involved in regulating growth and virulence in Sclerotinia sclerotiorum.
Int J Mol Sci
PUBLISHED: 03-17-2014
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MADS-box proteins, a well-conserved family of transcription factors in eukaryotic organisms, specifically regulate a wide range of cellular functions, including primary metabolism, cell cycle, and cell identity. However, little is known about roles of the MADS-box protein family in the fungal pathogen Sclerotinia sclerotiorum. In this research, the S. sclerotiorum MADS-box gene SsMADS was cloned; it encodes a protein that is highly similar to Mcm1 orthologs from Saccharomyces cerevisiae and other fungi, and includes a highly conserved DNA-binding domain. MADS is a member of the MADS box protein SRF (serum response factor) lineage. SsMADS function was investigated using RNA interference. Silenced strains were obtained using genetic transformation of the RNA interference vectors pS1-SsMADS and pSD-SsMADS. SsMADS expression levels in silenced strains were analyzed using RT-PCR. The results showed that SsMADS mRNA expression in these silenced strains was reduced to different degrees, and growth rate in these silenced strains was significantly decreased. Infecting tomato leaflets with silenced strains indicated that SsMADS was required for leaf pathogenesis in a susceptible host. Our results suggest that the MADS-box transcription factor SsMADS is involved in S. sclerotiorum growth and virulence.
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Pwp1 Is Required for the Differentiation Potential of Mouse Embryonic Stem Cells through Regulating Stat3 Signaling.
Stem Cells
PUBLISHED: 03-13-2014
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LIF/Stat3 signaling is critical for maintaining the self-renewal and differentiation potential of mouse embryonic stem cells (mES cells). However, the upstream effectors of this pathway have not been clearly defined. Here, we show that periodic tryptophan protein 1 (Pwp1), a WD-40 repeat-containing protein associated with histone H4 modification, is required for the exit of mES cells from the pluripotent state into all lineages. Knockdown of Pwp1 does not affect mES cell proliferation, self-renewal or apoptosis. However, knockdown of Pwp1 impairs the differentiation potential of mES cells both in vitro and in vivo. PWP1 ChIP-seq results revealed that the PWP1-occupied regions were marked with significant levels of H4K20me3. Moreover, Pwp1 binds to sites in the upstream region of Stat3. Knockdown of Pwp1 decreases the level of H4K20me3 in the upstream region of Stat3 gene and upregulates the expression of Stat3. Furthermore, Pwp1 knockdown (KD) mES cells recover their differentiation potential through suppressing the expression of Stat3 or inhibiting the tyrosine phosphorylation of STAT3. Together, our results suggest that Pwp1 plays important roles in the differentiation potential of mES cells. Stem Cells 2014.
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HucMSC-exosome mediated -Wnt4 signaling is required for cutaneous wound healing.
Stem Cells
PUBLISHED: 03-10-2014
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Mesenchymal stem cell-derived exosomes (MSC-Ex) play important roles in tissue injury repair, however, the roles of MSC-Ex in skin damage repair and its mechanisms are largely unknown. Herein, we examined the benefit of human umbilical cord mesenchymal stem cell derived exosome (hucMSC-Ex) in cutaneous wound healing using a rat skin burn model. We found that hucMSC-Ex-treated wounds exhibited significantly accelerated re-epithelialization, with increased expression of CK19, PCNA, collagen I (compared to collagen III) in vivo. HucMSC-Ex promoted proliferation and inhibited apoptosis of skin cells after heat-stress in vitro. We also discovered that Wnt4 was contained in hucMSC-Ex, and hucMSC-Ex derived Wnt4 promoted ?-catenin nuclear translocation and activity to enhance proliferation and migration of skin cells, which could be reversed by ?-catenin inhibitor ICG001. In vivo studies confirmed that the activation of Wnt/?-catenin by hucMSC-Ex played a key role in wound re-epithelialization and cell proliferation. Furthermore, knockdown of Wnt4 in hucMSC-Ex abrogated ?-catenin activation and skin cell proliferation and migration in vitro. The in vivo therapeutic effects were also inhibited when the expression of Wnt4 in hucMSC-Ex was interfered. In addition, the activation of AKT pathway by hucMSC-Ex was associated with the reduction of heat stress-induced apoptosis in rat skin burn model. Collectively, our findings indicate that exosome-delivered Wnt4 provides new aspects for the therapeutic strategy of MSCs in cutaneous wound healing. Stem Cells 2014.
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Infant mortality and life expectancy in China.
Med. Sci. Monit.
PUBLISHED: 03-08-2014
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It is reported that the infant mortality (IM) rate decreased rapidly in China and the life expectancy (LE) also had a high increase. Our objective was to determine the health status of the Chinese population by investigating IM and LE and their inter-relationship.
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From stem cells to red blood cells: how far away from the clinical application?
Sci China Life Sci
PUBLISHED: 02-15-2014
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The generation of red blood cells (RBCs) from stem cells provides a solution for deficiencies in blood transfusion. Currently, primary hematopoietic stem cells, embryonic stem cells and induced pluripotent stem cells have shown the potential to produce fully mature RBCs. Here, we discuss the advantages, induction protocols, progress and possible clinical applications of stem cells in RBC production.
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Quantitative determination of 26 steroids in eggs from various species using liquid chromatography-triple quadrupole-mass spectrometry.
J Chromatogr A
PUBLISHED: 02-11-2014
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A method for analyzing 26 types of steroids in egg matrix was developed. The method used liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) in electrospray ionization mode (ESI). The procedure involved extraction with acetonitrile and removal of phospholipids by zinc chloride (ZnCl?) followed by SPE cleanup with a Plexa cartridge. The effect of ZnCl? on phospholipid removal was directly observed using the post column infusion procedure. The SPE washing and elution conditions were optimized using a shallow gradient procedure. The free and conjugated steroids forms were determined using enzyme hydrolysis. The developed method resulted in satisfactory precision (RSD?15%), and the limits of quantification were between 0.05 and 25 ng/g depending on the steroid types. The recoveries ranged from 63.2% to 121.5%. Finally, the developed method was successfully applied to compare the steroids in eggs from different species (i.e., hen, duck, quail and pigeon eggs) or different raising system (i.e., normal vs. organic eggs). The steroids can be clearly clustered according to species and raising system. The hierarchical clustering analysis indicated similarity of the steroids among the species. The developed method is sensitive and useful for detection and quantification of steroids in eggs and can be used for residue control programs. In addition, the observed steroid content will provide a fundamental reference for food risk assessment analysis.
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Identification and characterization of the biosynthetic gene cluster of polyoxypeptin A, a potent apoptosis inducer.
BMC Microbiol.
PUBLISHED: 02-04-2014
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Polyoxypeptin A was isolated from a culture broth of Streptomyces sp. MK498-98 F14, which has a potent apoptosis-inducing activity towards human pancreatic carcinoma AsPC-1 cells. Structurally, polyoxypeptin A is composed of a C?? acyl side chain and a nineteen-membered cyclodepsipeptide core that consists of six unusual nonproteinogenic amino acid residues (N-hydroxyvaline, 3-hydroxy-3-methylproline, 5-hydroxypiperazic acid, N-hydroxyalanine, piperazic acid, and 3-hydroxyleucine) at high oxidation states.
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A priori prediction of tumor payload concentrations: preclinical case study with an auristatin-based anti-5T4 antibody-drug conjugate.
AAPS J
PUBLISHED: 01-23-2014
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The objectives of this investigation were as follows: (a) to validate a mechanism-based pharmacokinetic (PK) model of ADC for its ability to a priori predict tumor concentrations of ADC and released payload, using anti-5T4 ADC A1mcMMAF, and (b) to analyze the PK model to find out main pathways and parameters model outputs are most sensitive to. Experiential data containing biomeasures, and plasma and tumor concentrations of ADC and payload, following A1mcMMAF administration in two different xenografts, were used to build and validate the model. The model performed reasonably well in terms of a priori predicting tumor exposure of total antibody, ADC, and released payload, and the exposure of released payload in plasma. Model predictions were within two fold of the observed exposures. Pathway analysis and local sensitivity analysis were conducted to investigate main pathways and set of parameters the model outputs are most sensitive to. It was discovered that payload dissociation from ADC and tumor size were important determinants of plasma and tumor payload exposure. It was also found that the sensitivity of the model output to certain parameters is dose-dependent, suggesting caution before generalizing the results from the sensitivity analysis. Model analysis also revealed the importance of understanding and quantifying the processes responsible for ADC and payload disposition within tumor cell, as tumor concentrations were sensitive to these parameters. Proposed ADC PK model provides a useful tool for a priori predicting tumor payload concentrations of novel ADCs preclinically, and possibly translating them to the clinic.
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CAPE promotes the expansion of human umbilical cord blood-derived hematopoietic stem and progenitor cells in vitro.
Sci China Life Sci
PUBLISHED: 01-22-2014
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Due to the low number of collectable stem cells from single umbilical cord blood (UCB) unit, their initial uses were limited to pediatric therapies. Clinical applications of UCB hematopoietic stem and progenitor cells (HSPCs) would become feasible if there were a culture method that can effectively expand HSPCs while maintaining their self-renewal capacity. In recent years, numerous attempts have been made to expand human UCB HSPCs in vitro. In this study, we report that caffeic acid phenethyl ester (CAPE), a small molecule from honeybee extract, can promote in vitro expansion of HSPCs. Treatment with CAPE increased the percentage of HSPCs in cultured mononuclear cells. Importantly, culture of CD34(+) HSPCs with CAPE resulted in a significant increase in total colony-forming units and high proliferative potential colony-forming units. Burst-forming unit-erythroid was the mostly affected colony type, which increased more than 3.7-fold in 1 ?g mL(-1) CAPE treatment group when compared to the controls. CAPE appears to induce HSPC expansion by upregulating the expression of SCF and HIF1-?. Our data suggest that CAPE may become a potent medium supplement for in vitro HSPC expansion.
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Cytotoxic polyphenols from a sponge-associated fungus Aspergillus versicolor Hmp-48.
Chem. Biodivers.
PUBLISHED: 01-21-2014
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A new dibenzo[1,4]dioxin 1, and two new prenylated diphenyl ethers, 2 and 3, together with six known compounds, 4-9, were isolated from a sponge-associated fungus Aspergillus versicolor Hmp-F48 by bioactivity-guided fractionation. Their structures were elucidated by 1D- and 2D-NMR, and MS analyses. The compounds showed potent cell growth inhibitory activities against HL-60 cell line.
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[Inhibition of Fasudil on lipopolysaccharide-induced TNF-? and IL-1? expressions through TLR4 pathway in murine BV-2 cells in vitro].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 01-11-2014
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To evaluate the effects of Fasudil on the production of proinflammatory cytokines in lipopolysaccharide (LPS)-stimulated BV-2 microglia cells.
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Crystal structures and kinetic properties of enoyl-acyl carrier protein reductase I from Candidatus Liberibacter asiaticus.
Protein Sci.
PUBLISHED: 01-06-2014
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Huanglongbing (HLB) is a destructive citrus disease. The leading cause of HLB is Candidatus Liberibacter asiaticus. Fatty acid biosynthesis is essential for bacterial viability and has been validated as a target for the discovery of novel antibacterial agents. Enoyl-acyl carrier protein reductase (also called ENR or FabI and a product of the fabI gene) is an enzyme required in a critical step of bacterial fatty acid biosynthesis and has attracted attention as a target of novel antimicrobial agents. We determined the crystal structures of FabI from Ca. L. asiaticus in its apoform as well as in complex with b-nicotinamide adenine dinucleotide (NAD) at 1.7 and 2.7 Å resolution, respectively, to facilitate the design and screening of small molecule inhibitors of FabI. The monomeric ClFabI is highly similar to other known FabI structures as expected; however, unlike the typical tetramer, ClFabI exists as a hexamer in crystal, whereas as dimer in solution, on the other hand, the substrate binding loop which always disordered in apoform FabI structures is ordered in apo-ClFabI. Interestingly, the structure of ClFabI undergoes remarkable conformational change in the substrate-binding loop in the presence of NAD. We conclude that the signature sequence motif of FabI can be considered as Gly-(Xaa)5-Ser-(Xaa)n-Val-Tyr-(Xaa)6-Lys-(Xaa)n-Thr instead of Tyr-(Xaa)6-Lys. We have further identified isoniazid as a competitive inhibitor with NADH.
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Pterostilbene attenuates lipopolysaccharide-induced learning and memory impairment possibly via inhibiting microglia activation and protecting neuronal injury in mice.
Prog. Neuropsychopharmacol. Biol. Psychiatry
PUBLISHED: 01-03-2014
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The present study aims to evaluate the effects of pterostilbene on lipopolysaccharide (LPS)-induced learning and memory impairment as well as the possible changes of microglia and neurons. Firstly, learning and memory function was investigated by behavioral tests. Pterostilbene attenuated LPS-induced learning and memory impairment tested by Y-maze and Morris water maze. Secondly, immunohistochemical method was used to study the changes of microglia and neurons. The results showed that pterostilbene produced a significant decrease in the number of Iba-1 and Doublecortin (DCX) positive cells and a significant increase in neuronal nuclear antigen (NeuN)-stained area of neurons in mouse hippocampal compared to the LPS group. Finally, an in vitro study was performed to further confirm the inhibitory effect on microglia activation and protective effect on neurons exerted by pterostilbene. The results demonstrated that pterostilbene significantly inhibited microglia activation, showing the obvious decrease of LPS-induced production of NO, TNF-? and IL-6 in N9 microglial cells. In addition, the viability of SH-SY5Y cells decreased by conditioned media of LPS-activated N9 microglial cells was remarkably recovered by pterostilbene. In summary, the present study demonstrated for the first time that pterostilbene attenuated LPS-induced learning and memory impairment, which may be associated with its inhibitory effect on microglia activation and protective effect on neuronal injury.
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Listeria infection in Chinese pregnant women and neonates from Shandong.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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This study aims to investigate the characters of pregnant women and neonates with listeria monocytogenes infections (L. monocytogenes) in Shandong of China.
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Compositions and Anti-Tumor Activity of Pyropolyporus fomentarius Petroleum Ether Fraction In Vitro and In Vivo.
PLoS ONE
PUBLISHED: 01-01-2014
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The chemical compositions and anti-tumor activities of the petroleum ether fraction (PE), from mushroom Pyropolyporus fomentarius, were studied. Upon gas chromatography-mass spectrometry (GC-MS) analysis, nine major constituents were identified in the fraction. In vitro, the PE showed cytotoxic activity against murine sarcoma S180 (S180) cells in a dose- and time-dependent manner, and the cytotoxic effects were associated with apoptosis. The mitochondrial membrane potential loss and the intracellular ROS generation were greatly increased in the Pyropolyporus fomentarius PE treated group, suggesting cell apoptosis, induced by the PE in S180 cells, might be mitochondria dependent and ROS mediated. Consistent with in vitro findings, the in vivo study showed that the Pyropolyporus fomentarius PE was also effective in inhibiting the tumor growth induced by S180 cells and had lower immune organ toxicity. We found that the Pyropolyporus fomentarius PE has significant anti-tumor activity and great potential in screening anti-tumor drugs.
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Observation of linear and quadratic magnetic field-dependence of magneto-photocurrents in InAs/GaSb superlattice.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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We experimentally studied the magneto-photocurrents generated by direct interband transition in InAs/GaSb type II superlattice. By varying the magnetic field direction, we observed that an in-plane magnetic field induces a photocurrent linearly proportional to the magnetic field; however, a magnetic field tilted to the sample plane induces a photocurrent presenting quadratic magnetic field dependence. The magneto-photocurrents in both conditions are insensitive to the polarization state of the incident light. Theoretical models involving excitation, relaxation and Hall effect are utilized to explain the experimental results.
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Prevalence patterns of avian Plasmodium and Haemoproteus parasites and the influence of host relative abundance in southern China.
PLoS ONE
PUBLISHED: 01-01-2014
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Infectious diseases threaten the health and survival of wildlife populations. Consequently, relationships between host diversity, host abundance, and parasite infection are important aspects of disease ecology and conservation research. Here, we report on the prevalence patterns of avian Plasmodium and Haemoproteus infections and host relative abundance influence based on sampling 728 wild-caught birds representing 124 species at seven geographically widespread sites in southern China. The overall prevalence of two haemoprotozoan parasites, Plasmodium and Haemoproteus, was 29.5%, with 22.0% attributable to Haemoproteus and 7.8% to Plasmodium. Haemoproteus prevalence differed significantly among different avian host families, with the highest prevalence in Nectariniidae, Pycnonotidae and Muscicapidae, whereas Plasmodium prevalence varied significantly among host species. Seventy-nine mitochondrial lineages including 25 from Plasmodium and 54 from Haemoproteus were identified, 80% of which were described here for the first time. The phylogenetic relationships among these parasites indicated stronger host-species specificity for Haemoproteus than Plasmodium. Well-supported host-family (Timaliidae) specific clades were found in both Plasmodium and Haemoproteus. The Haemoproteus tree shows regional subclades, whereas the Plasmodium clades are "scattered" among different geographical regions. Interestingly, there were statistically significant variations in the prevalence of Plasmodium and Haemoproteus among the geographical regions. Furthermore, the prevalence of Plasmodium and Haemoproteus were not significantly correlated with host relative abundance. Further efforts will focus on exploring the relationships between parasite prevalence and sex, age, and immune defense of the host.
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Genome wide association study identifies 20 novel promising genes associated with milk fatty acid traits in Chinese Holstein.
PLoS ONE
PUBLISHED: 01-01-2014
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Detecting genes associated with milk fat composition could provide valuable insights into the complex genetic networks of genes underling variation in fatty acids synthesis and point towards opportunities for changing milk fat composition via selective breeding. In this study, we conducted a genome-wide association study (GWAS) for 22 milk fatty acids in 784 Chinese Holstein cows with the PLINK software. Genotypes were obtained with the Illumina BovineSNP50 Bead chip and a total of 40,604 informative, high-quality single nucleotide polymorphisms (SNPs) were used. Totally, 83 genome-wide significant SNPs and 314 suggestive significant SNPs associated with 18 milk fatty acid traits were detected. Chromosome regions that affect milk fatty acid traits were mainly observed on BTA1, 2, 5, 6, 7, 9, 13, 14, 18, 19, 20, 21, 23, 26 and 27. Of these, 146 SNPs were associated with more than one milk fatty acid trait; most of studied fatty acid traits were significant associated with multiple SNPs, especially C18:0 (105 SNPs), C18 index (93 SNPs), and C14 index (84 SNPs); Several SNPs are close to or within the DGAT1, SCD1 and FASN genes which are well-known to affect milk composition traits of dairy cattle. Combined with the previously reported QTL regions and the biological functions of the genes, 20 novel promising candidates for C10:0, C12:0, C14:0, C14:1, C14 index, C18:0, C18:1n9c, C18 index, SFA, UFA and SFA/UFA were found, which composed of HTR1B, CPM, PRKG1, MINPP1, LIPJ, LIPK, EHHADH, MOGAT1, ECHS1, STAT1, SORBS1, NFKB2, AGPAT3, CHUK, OSBPL8, PRLR, IGF1R, ACSL3, GHR and OXCT1. Our findings provide a groundwork for unraveling the key genes and causal mutations affecting milk fatty acid traits in dairy cattle.
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Enhancement of the HIF-1?/15-LO/15-HETE axis promotes hypoxia-induced endothelial proliferation in preeclamptic pregnancy.
PLoS ONE
PUBLISHED: 01-01-2014
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Preeclampsia (PE) is an extremely serious condition in pregnant women and the leading cause of maternal and fetal morbidity and mortality. Despite active research, the etiological factors of this disorder remain elusive. The increased release of 15-hydroxyeicosatetraenoic acid (15-HETE) in the placenta of preeclamptic patients has been studied, but its exact role in PE pathogenesis remains unknown. Mounting evidence shows that PE is associated with placental hypoxia, impaired placental angiogenesis, and endothelial dysfunction. In this study, we confirmed the upregulated expression of hypoxia-inducible factor 1? (HIF-1?) and 15-lipoxygenase-1/2 (15-LO-1/2) in patients with PE. Production of the arachidonic acid metabolite, 15-HETE, also increased in the preeclamptic placenta, which suggests enhanced activation of the HIF-1?-15-LO-15-HETE axis. Furthermore, this study is the first to show that the umbilical cord of preeclamptic women contains significantly higher serum concentrations of 15-HETE than that of healthy pregnant women. The results also show that expression of 15-LO-1/2 is upregulated in both human umbilical vein endothelial cells (HUVECs) collected from preeclamptic women and in those cultured under hypoxic conditions. Exogenous 15-HETE promotes the migration of HUVECs and in vitro tube formation and promotes cell cycle progression from the G0/G1 phase to the G2/M + S phase, whereas the 15-LO inhibitor, NDGA, suppresses these effects. The HIF-1?/15-LO/15-HETE pathway is therefore significantly associated within the pathology of PE.
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Tree-ring based may-july temperature reconstruction since AD 1630 on the Western Loess Plateau, China.
PLoS ONE
PUBLISHED: 01-01-2014
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Tree-ring samples from Chinese Pine (Pinus tabulaeformis Carr.) collected at Mt. Shimen on the western Loess Plateau, China, were used to reconstruct the mean May-July temperature during AD 1630-2011. The regression model explained 48% of the adjusted variance in the instrumentally observed mean May-July temperature. The reconstruction revealed significant temperature variations at interannual to decadal scales. Cool periods observed in the reconstruction coincided with reduced solar activities. The reconstructed temperature matched well with two other tree-ring based temperature reconstructions conducted on the northern slope of the Qinling Mountains (on the southern margin of the Loess Plateau of China) for both annual and decadal scales. In addition, this study agreed well with several series derived from different proxies. This reconstruction improves upon the sparse network of high-resolution paleoclimatic records for the western Loess Plateau, China.
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Epidemiological and etiological characteristics of fever, thrombocytopenia and leukopenia syndrome in Henan Province, China, 2011-2012.
PLoS ONE
PUBLISHED: 01-01-2014
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The Fever, Thrombocytopenia and Leukopenia Syndrome (FTLS) is caused by a bunyavirus known as the FTLS virus (FTLSV), which was recently discovered in China. We examined the epidemiological and etiological features of 637 laboratory-confirmed cases of FTLS with onset from January 2011 to December 2012 in Henan Province, China. The highest incidence of FTLS occurred between May and August: 76.5% of all laboratory-confirmed cases occurred during those four months. Of the laboratory-confirmed cases, 60.9% were in the 46-69 years old age groups; 96.1% (612/637) occurred in farmers; 98.1% (625/637) were reported from Xinyang Prefecture. During the same time period, 2047 cases were reported in China. The nucleotide and amino acid sequences of FTLSV strains identified during 2011-2012 in Henan Province were ? 96% identical. This findings provides insight for developing public-health interventions for the control and prevention of FTLS in epidemic area.
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[Advances on Mechanisms of Coagulation with Non-small Cell Lung Cancer].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 12-19-2013
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Recently, researchers have been increasingly finding coagulation disorders are commonly the first sign of malignancy. It has now been established that cancer development leads to an increased risk of thrombosis, and conversely, excessive activation of blood coagulation profoundly influences cancer progression. In patients with lung cancer, a sustained stimulation of blood coagulation takes place. Cancer cells trigger coagulation through expression of tissue factor, and affect coagulation through expression of thrombin, release of microparticles that augment coagulation and so on. Coagulation also facilitates tumour progression through release of platelet granule contents, inhibition of natural killer cells and recruitment of macrophages. Non-small cell lung cancer (NSCLC) accounts for about 80%-85% of all lung malignancies. In the present review, we summarized the newly updated data about the physiopathological mechanisms of various components of the clotting system in different stages of carcinogenesis in NSCLC.
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Inhibition of ?-Catenin Signaling Involved in the Biological Activities of a Lignan E2S Isolated from Carya cathayensis Fruits.
Planta Med.
PUBLISHED: 11-11-2013
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Carya cathayensis is a fruit-bearing plant that belongs to the Juglandaceae family and is widely distributed throughout the world. It possesses various important biological activities. We have previously isolated an antitumor compound from the shell of C. cathayensis fruits and named it E2S ((E)-3-[(2S,3R)-2,3-dihydro-2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-7-methoxy-1-benzo[b]furan-5-yl]-2-propenal). In this study, we investigated the antitumor activity of E2S against various human colorectal cancer cell lines (HCT116, HT29, SW480, LoVo). The results showed that E2S could significantly inhibit the growth of cancer cells in a dose-dependent manner, as well as disrupt the progression of the cell cycle. Mechanistic study revealed that E2S could decrease the protein levels of ?-catenin and its downstream targets (such as c-myc, a key transcriptional target of ?-catenin) in the cells. In addition, it also significantly suppressed ?-catenin/TCF transcriptional activity. Taken together, the results suggested that E2S might partially exert an antiproliferative effect on human colorectal cancer cells by targeting ?-catenin signaling, a finding that might potentially translate into a chemotherapeutic strategy for the treatment of cancer. It might also have implications for cancer prevention strategies.
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The small molecule Me6TREN mobilizes hematopoietic stem/progenitor cells by activating MMP-9 expression and disrupting SDF-1/CXCR4 axis.
Blood
PUBLISHED: 11-06-2013
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Mobilization of hematopoietic stem and progenitor cells (HSPCs) from bone marrow into the blood circulation has been widely used for hematopoietic transplantation. However, the current methods of cytokine- or small-molecule-stimulated HSPC mobilization are far from satisfactory. New mobilizing agents are needed to increase the number of stem cells in peripheral blood for effective reconstitution of hematopoiesis. Here, we report that the molecule Me6TREN (Me6) can induce rapid mobilization of hematopoietic progenitor cells, and that Me6 exhibits more significant effects than G-CSF or AMD3100. Me6 also mobilizes long-term repopulating cells, which successfully engraft and expand in a multilineage fashion in primary and secondary transplant recipients. Mechanistically, Me6 inhibits both the SDF-1?-induced migration and VLA-4-mediated adhesion of mouse and human hematopoietic cells. Me6 appears to mobilize HSPCs by activating MMP-9 expression and disrupting the SDF-1?/CXCR4 axis. Therefore, Me6 may become a new, potent and efficacious mobilizing agent of HSPCs.
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Preparation and characterization of dry method esterified starch/polylactic acid composite materials.
Int. J. Biol. Macromol.
PUBLISHED: 09-30-2013
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Corn starch and maleic anhydride were synthesized from a maleic anhydride esterified starch by dry method. Fourier transform infrared spectroscopy (FTIR) was used for the qualitative analysis of the esterified starches. The reaction efficiency of dry method esterified starch reached 92.34%. The dry method esterified starch was blended with polylactic acid (PLA), and the mixture was melted and extruded to produce the esterified starch/polylactic acid (ES/PLA) composites. The degree of crystallinity of the ES/PLA was lower than that of the NS/PLA, indicating that the relative dependence between these two components of starch and polylactic acid was enhanced. Scanning electron microscopy (SEM) indicated that the dry method esterified starch increased the two-phase interface compatibility of the composites, thereby improving the tensile strength, bending strength, and elongation at break of the ES/PLA composite. The introduction of a hydrophobic ester bond and increase in interface compatibility led to an increase in ES/PLA water resistance. Melt index determination results showed that starch esterification modification had improved the melt flow properties of starch/PLA composite material. Strain scanning also showed that the compatibility of ES/PLA was increased. While frequency scanning showed that the storage modulus and complex viscosity of ES/PLA was less than that of NS/PLA.
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Nrf2 deletion causes "benign" simple steatosis to develop into nonalcoholic steatohepatitis in mice fed a high-fat diet.
Lipids Health Dis
PUBLISHED: 09-29-2013
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Nonalcoholic fatty liver disease begins with the aberrant accumulation of triglyceride in the liver. Its spectrum includes the earliest stage of hepatic simple steatosis (SS), nonalcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular carcinoma. Generally, hepatic SS is often self-limited; however 10%-30% of patients with hepatic SS progress to NASH. The cause(s) of the transition from SS to NASH are unclear. We aimed to test the contribution of nuclear erythroid 2-related factor 2 (Nrf2) on the progression of "benign" SS to NASH in mice fed a high fat diet. In doing so, we discovered the influence of fatty acid in that progression.
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Effects of polymorphic DNA on the fluorescent properties of silver nanoclusters.
Photochem. Photobiol. Sci.
PUBLISHED: 08-16-2013
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Silver nanoclusters (Ag NCs) with emission wavelengths from 538 nm to 706 nm were synthesized using a series of G-/C-rich polymorphic DNA templates. Thermodynamic studies on the interactions of Ag(+) with polymorphic DNA indicate that the binding affinities greatly depend on the secondary structures of DNA templates, with a decreasing order: the coiled C-rich strand > the i-motif > the duplex > the G-quadruplex. Fluorescent Ag NCs prepared using these polymorphic DNA templates show that fluorescence stabilities are associated with the binding affinities between DNA templates and Ag(+), e.g., the coiled C-rich strand C4A4C3 with the highest binding constant (40.2 × 10(5) M(-1)) stabilizes Ag NCs for over 300 h, while the G-quadruplex G4T4G4 with the lowest binding constant (0.64 × 10(5) M(-1)) generates Ag NCs with the shortest shelf-life (55 h). The cluster sizes of Ag NCs are associated with the sequence lengths of DNA templates. In addition, the red emitting [C4A4C3]-Ag and the NIR emitting [G4T4G4-C4A4C4]-Ag are successfully used for HeLa cell transfection and exhibit good intracellular emission. These results provide a promising pathway to prepare silver nanomaterials with desirable physicochemical properties through designing suitable DNA templates.
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Quantification of shape and cell polarity reveals a novel mechanism underlying malformations resulting from related FGF mutations during facial morphogenesis.
Hum. Mol. Genet.
PUBLISHED: 08-01-2013
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Fibroblast growth factor (FGF) signaling mutations are a frequent contributor to craniofacial malformations including midfacial anomalies and craniosynostosis. FGF signaling has been shown to control cellular mechanisms that contribute to facial morphogenesis and growth such as proliferation, survival, migration and differentiation. We hypothesized that FGF signaling not only controls the magnitude of growth during facial morphogenesis but also regulates the direction of growth via cell polarity. To test this idea, we infected migrating neural crest cells of chicken embryos with  replication-competent avian sarcoma virus expressing either FgfR2(C278F), a receptor mutation found in Crouzon syndrome or the ligand Fgf8. Treated embryos exhibited craniofacial malformations resembling facial dysmorphologies in craniosynostosis syndrome. Consistent with our hypothesis, ectopic activation of FGF signaling resulted in decreased cell proliferation, increased expression of the Sprouty class of FGF signaling inhibitors, and repressed phosphorylation of ERK/MAPK. Furthermore, quantification of cell polarity in facial mesenchymal cells showed that while orientation of the Golgi body matches the direction of facial prominence outgrowth in normal cells, in FGF-treated embryos this direction is randomized, consistent with aberrant growth that we observed. Together, these data demonstrate that FGF signaling regulates cell proliferation and cell polarity and that these cell processes contribute to facial morphogenesis.
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Enrichment and purification of total flavonoids from Flos Populi extracts with macroporous resins and evaluation of antioxidant activities in vitro.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 07-30-2013
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Enrichment and purification of total flavonoids from Flos Populi extracts were studied using five macroporous resins. The static tests indicated that NKA-9 resin was appropriate and its adsorption data were well fitted to the Langmuir and Freundlich isotherms. To optimize the separation process, dynamic adsorption and desorption tests were carried out. The optimal adsorption parameters were initial concentrations in sample solution of 7.64mg/mL, pH of 5.0, sample loading amount of 2.3BV, flow rate of 2BV/h, temperature of 25°C. The optimal desorption parameters were deionized water and 20% ethanol each 5BV, then 60% ethanol of 10 BV, flow rate of 2BV/h. After one run treatment with NKA-9 resin, the content of total flavonoids in the product increased from 11.38% to 53.41%, and the recovery yield was 82.24%. The results showed that NKA-9 resin revealed a good ability to enrichment total flavonoids from Flos Populi, and the method can be referenced for the enrichment of total flavonoids from other materials. The antioxidant activities of the purified flavonoids were further evaluated in vitro. It showed that the DPPH radical scavenging increased from 59.46% to 82.63% at different concentrations (0.06-0.14mg/mL). At different concentrations (0.6-1.4mg/mL), the hydroxyl radical scavenging increased from 35.39% to 74.12%. Moreover, the reducing ability and total oxidant capacity appeared to be dose-dependent of flavonoids. It indicated that the purified flavonoids can be used as a source of potential antioxidant.
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Modeling of Friedreich ataxia-related iron overloading cardiomyopathy using patient-specific-induced pluripotent stem cells.
Pflugers Arch.
PUBLISHED: 07-18-2013
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Friedreich ataxia (FRDA), a recessive neurodegenerative disorder commonly associated with hypertrophic cardiomyopathy, is due to GAA repeat expansions within the first intron of the frataxin (FXN) gene encoding the mitochondrial protein involved in iron-sulfur cluster biosynthesis. The triplet codon repeats lead to heterochromatin-mediated gene silencing and loss of frataxin. Nevertheless, inadequacy of existing FRDA-cardiac cellular models limited cardiomyopathy studies. We tested the hypothesis that iron homeostasis deregulation accelerates reduction in energy synthesis dynamics which contributes to impaired cardiac calcium homeostasis and contractile force. Silencing of FXN expressions occurred both in somatic FRDA-skin fibroblasts and two of the induced pluripotent stem cells (iPSC) clones; a sign of stress condition was shown in FRDA-iPSC cardiomyocytes with disorganized mitochondrial network and mitochondrial DNA (mtDNA) depletion; hypertrophic cardiac stress responses were observed by an increase in ?-actinin-positive cell sizes revealed by FACS analysis as well as elevation in brain natriuretic peptide (BNP) gene expression; the intracellular iron accumulated in FRDA cardiomyocytes might be due to attenuated negative feedback response of transferring receptor (TSFR) expression and positive feedback response of ferritin (FTH1); energy synthesis dynamics, in terms of ATP production rate, was impaired in FRDA-iPSC cardiomyocytes, which were prone to iron overload condition. Energetic insufficiency determined slower Ca(2+) transients by retarding calcium reuptake to sarcoplasmic reticulum (SR) and impaired the positive inotropic and chronotropic responses to adrenergic stimulation. Our data showed for the first time that FRDA-iPSCs cardiac derivatives represent promising models to study cardiac stress response due to impaired iron homeostasis condition and mitochondrial damages. The cardiomyopathy phenotype was accelerated in an iron-overloaded condition early in calcium homeostasis aspect.
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Dual-targeted nanocarrier based on cell surface receptor and intracellular mRNA: an effective strategy for cancer cell imaging and therapy.
Anal. Chem.
PUBLISHED: 07-02-2013
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Developing efficient methods for targeting cancer cells and encapsulating drugs coupled with activated release holds enormous potential for cancer cell imaging and therapy. Herein, a novel dual-targeted nanocarrier was developed on the basis of gold nanoparticles modified with a dense shell of synthetic oligonucleotides. The folic acid functionalized single-stranded DNA was designed to target the folate receptor on the cancer cell surface, and the molecular beacon was employed as drug carrier for activated release associated with intracellular tumor mRNA. Intracellular experiments indicated that the dual-targeted nanocarrier could be preferentially internalized into cancer cells due to the folate receptor targeting and release Doxorubicin (Dox) selectively in cancer cells because of the activated release with intracellular mRNA. The nanocarrier could reduce the dosage and greatly improve the therapeutic effect of drugs in cancer cells. Moreover, the nanocarrier can identify the changes of the express level of tumor mRNA and release Dox in a controlled manner in cancer cells, which would be beneficial for cancer therapy.
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Synthesis and characterization of maleic anhydride esterified corn starch by the dry method.
Int. J. Biol. Macromol.
PUBLISHED: 06-29-2013
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Maleic anhydride esterified starch was synthesized by a dry method using corn starch as the material and maleic anhydride as the esterifying agent. The esterified starch (ES) was analyzed by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), which confirmed that there was a successful esterification reaction between the maleic anhydride and corn starch. The effects of reaction temperature and time on the degree of substitution of esterified starch were studied, where the results showed that 80°C of reaction temperature and 3h of reaction time were optimal conditions. The result of XPS testing demonstrated that the esterification reaction led to increase of ester bonds in starch. The scanning electron microscopy (SEM) and laser particle size analyzer results showed that esterification led to roughness on the surface of the starch particle, and the particle size and distribution rate of esterification starch became larger. X-ray diffraction (XRD) analysis demonstrated that esterification reaction did not change the crystalline type of native starch. The differential scanning calorimeter (DSC) and thermo gravimetric analysis (TGA) confirmed that destruction of the crystal structure resulted in improved thermoplasticity of the starch, decreased the gelatinization temperature and increased the thermogravimetric rate of esterification starch.
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Forsythiaside attenuates lipopolysaccharide-induced inflammatory responses in the bursa of Fabricius of chickens by downregulating the NF-?B signaling pathway.
Exp Ther Med
PUBLISHED: 06-23-2013
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Forsythiaside, a phenylethanoside product isolated from air-dried fruits of Forsythia suspensa, has been demonstrated to exhibit antioxidant, antibacterial and anti-inflammatory activities in vitro. However, its mechanism and the effects of lipopolysaccharide (LPS)-induced injury on the bursa of Fabricius (BF) of chickens are poorly understood. The present study aimed to investigate the anti-inflammatory effects of forsythiaside on LPS-induced acute inflammation. In addition, the potential molecular mechanisms of forsythiaside were analyzed in the BF, a special immune organ in chickens. Forty 15-day-old chickens were randomly divided into control, LPS and LPS plus forsythiaside (30 or 60 mg/kg) groups (n=10 for each group). In the LPS plus forsythiaside (30 or 60 mg/kg) groups, the chickens were orally administered with forsythiaside at doses of 30 and 60 mg/kg for seven days. At 21 days old, the chickens were intravenously injected with 200 ?g/kg body weight LPS. Chickens in the control and LPS groups were only administered with vehicle or LPS, respectively, at day 21. At 3 h post-injection, the body temperature and nitric oxide (NO) levels were analyzed. In addition, the levels and mRNA expression of pro-inflammatory cytokines, including tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6) and IL-1?, and the mRNA expression of nuclear factor-?B (NF-?B), cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS), were examined in the BFs isolated from the chickens. The results revealed that forsythiaside was able to attenuate the LPS-induced inflammatory responses in the BFs of the chickens. The mechanisms by which forsythiaside exerted its anti-inflammatory effect were found to correlate with the inhibition of IL-6, IL-1?, TNF-? and COX-2 production, via the inactivation of NF-?B, indicating that the NF-?B-iNOS-NO signaling pathway may be important in this process.
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Anti-tumor activity of three novel derivatives of ginsenoside on colorectal cancer cells.
Steroids
PUBLISHED: 06-19-2013
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25-Hydroxyprotopanaxadiol (25-OH-PPD) is a natural compound isolated from Panax ginseng, and its anti-tumor activity has been studied in previous publication. In the current study, we investigated the anti-tumor activity of three novel derivatives synthesized from 25-OH-PPD, namely (20R)-12?-O-(l-chloracetyl)-dammarane-3?, 20, 25-triol (xl), (20R)-3?-O-(l-alanyl)-dammarane-12?, 20, 25-triol (1c), and (20R)-3?-O-(Boc-l-arginyl)-dammarane-12?, 20, 25-triol (8b). All three compounds significantly inhibited the growths of human colorectal cancer cells, while having lesser effect on the growth of normal primary muscle cells and spleno-lymphocytes. Further mechanistic study demonstrated that these compounds could induce apoptosis by activating the components of caspase-signaling pathways in HCT116 cells, but not in spleno-lymphocytes. Taken together, the results suggested that 25-OH-PPD derivatives exerted promising anti-tumor activity that is specific to human colorectal cancer cells, and may therefore represent a potential chemotherapeutic strategy for the treatment of colorectal cancer.
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Targeted mutations in a highly conserved motif of the nsp1? protein impair the interferon antagonizing activity of porcine reproductive and respiratory syndrome virus.
J. Gen. Virol.
PUBLISHED: 06-12-2013
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Non-structural protein 1? (nsp1?) of porcine reproductive and respiratory syndrome virus (PRRSV) contains a papain-like cysteine protease (PLP?) domain and has been identified as the main viral protein antagonizing the host innate immune response. In this study, nsp1? was determined to suppress the expression of reporter genes as well as to suppress self-expression in transfected cells, and this activity appeared to be associated with its interferon (IFN) antagonist function. To knock down the effect of nsp1? on IFN activity, a panel of site-specific mutations in nsp1? was analysed. Double mutations K130A/R134A (type 1 PRRSV) or K124A/R128A (type 2 PRRSV) targeting a highly conserved motif of nsp1?, GKYLQRRLQ (in bold), impaired the ability of nsp1? to suppress IFN-? and reporter gene expression, as well as to suppress self-expression in vitro. Subsequently, viable recombinant viruses vSD01-08-K130A/R134A and vSD95-21-K124A/R128A, containing double mutations in the GKYLQRRLQ motif were generated using reverse genetics. In comparison with WT viruses, these nsp1? mutants showed impaired growth ability in infected cells, but the PLP? cleavage function was not directly affected. The expression of selected innate immune genes was determined in vSD95-21-K124A/R128A mutant-infected cells. The results consistently showed that gene expression levels of IFN-?, IFN-? and IFN-stimulated gene 15 were upregulated in cells that were infected with the vSD95-21-K124A/R128A compared with that of WT virus. These data suggest that PRRSV nsp1? may selectively suppress cellular gene expression, including expression of genes involved in the host innate immune function. Modifying the key residues in the highly conserved GKYLQRRLQ motif could attenuate virus growth and improve the cellular innate immune responses.
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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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