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Find video protocols related to scientific articles indexed in Pubmed.
A stationary computed tomography system with cylindrically distributed sources and detectors.
J Xray Sci Technol
PUBLISHED: 11-20-2014
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The temporal resolution of current computed tomography (CT) systems is limited by the rotation speed of their gantries.OBJECTIVE: A helical interlaced source detector array (HISDA) CT, which is a stationary CT system with distributed X-ray sources and detectors, is presented in this paper to overcome the aforementioned limitation and achieve high temporal resolution.METHODS: Projection data can be obtained from different angles in a short time and do not require source, detector, or object motion. Axial coverage speed is increased further by employing a parallel scan scheme. Interpolation is employed to approximate the missing data in the gaps, and then a Katsevich-type reconstruction algorithm is applied to enable an approximate reconstruction.RESULTS: The proposed algorithm suppressed the cone beam and gap-induced artifacts in HISDA CT. The results also suggest that gap-induced artifacts can be reduced by employing a large helical pitch for a fixed gap height.CONCLUSIONS: HISDA CT is a promising 3D dynamic imaging architecture given its good temporal resolution and stationary advantage.
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New Microbleeds After Thrombolysis: Contiguous Thin-Slice 3T MRI.
Medicine (Baltimore)
PUBLISHED: 11-04-2014
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We aimed to determine the frequency of new microbleeds after intravenous thrombolysis using contiguous thin-slice 3T magnetic resonance imaging. We retrospectively examined clinical and imaging data from 121 consecutive acute ischemic stroke patients who underwent magnetic resonance imaging before and 24 hours after intravenous thrombolysis. Of the included patients, 44 (36.4%) were women, with a median age of 69 years (range, 35-94 years). A total of 363 baseline microbleeds were observed in 57 patients and 8 new microbleeds in 6 patients. Multiple regression analysis indicated that baseline infarct volume (odds ratio, 1.556/10?mL; 95% CI, 1.017-2.379; P?=?0.04) and systolic blood pressure (odds ratio, 1.956/10?mm Hg; 95% CI, 1.056-3.622; P?=?0.03), but not the presence of baseline microbleeds, were independently associated with new microbleeds. The frequency of neither symptomatic intracranial hemorrhage nor remote hemorrhage or any hemorrhagic transformation was different between patients with and without new microbleeds (0.0% vs 1.7%, P?>?0.99; 0.0% vs 1.7%, P?>?0.99; 50.0% vs 28.7%, P?=0.36). New microbleeds developed rapidly 24 hours after intravenous thrombolysis. The significance of these new microbleeds and their effect on cognitive and functional outcome merits further investigation.
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Discovery and Preclinical Profiling of 3-[4-(Morpholin-4-yl)-7H-pyrrolo[2,3-d]pyrimidin-5-yl]benzonitrile (PF-06447475), a Highly Potent, Selective, Brain Penetrant, and in Vivo Active LRRK2 Kinase Inhibitor.
J. Med. Chem.
PUBLISHED: 10-30-2014
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Leucine rich repeat kinase 2 (LRRK2) has been genetically linked to Parkinson's disease (PD) by genome-wide association studies (GWAS). The most common LRRK2 mutation, G2019S, which is relatively rare in the total population, gives rise to increased kinase activity. As such, LRRK2 kinase inhibitors are potentially useful in the treatment of PD. We herein disclose the discovery and optimization of a novel series of potent LRRK2 inhibitors, focusing on improving kinome selectivity using a surrogate crystallography approach. This resulted in the identification of 14 (PF-06447475), a highly potent, brain penetrant and selective LRRK2 inhibitor which has been further profiled in in vivo safety and pharmacodynamic studies.
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Draft Genome Sequence of the Novel Exopolysaccharide-Producing Bacterium Altibacter lentus Strain JLT2010T, Isolated from Deep Seawater of the South China Sea.
Genome Announc
PUBLISHED: 10-25-2014
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Altibacter lentus strain JLT2010(T) is the type strain of the recently identified novel genus and species of the family Flavobacteriaceae and was first isolated from deep seawater of the South China Sea. It can produce exopolysaccharide. Here we report the first draft genome of JLT2010(T) (3,160,033 bp, with GC content of 42.12%) and major findings from its annotation. It is the first reported genome in the genus Altibacter.
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The Maize DWARF1 Encodes a Gibberellin 3-Oxidase and Is Dual-Localized to the Nucleus and Cytosol.
Plant Physiol.
PUBLISHED: 10-25-2014
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The maize GA deficient mutant dwarf1 (d1) displays dwarfism and andromonoecy (i.e. forming anthers in the female flower). Previous characterization indicated that the d1 mutation blocked three steps in the GA biosynthesis; however, the locus has not been isolated and characterized. Here we report that D1 encodes a GA 3-oxidase catalyzing the final step of bioactive GA synthesis. Recombinant DWARF1 (D1) is capable to convert GA20 to GA1, GA20 to GA3, GA5 to GA3 and GA9 to GA4 in vitro. These reactions are widely believed to take place in the cytosol. However, both in vivo GFP fusion analysis and western blotting of organelle fractions using a D1 specific antibody revealed that the D1 protein is dual-localized in the nucleus and the cytosol. Furthermore, the up-stream ZmGA20ox1 protein was found dual-localized in the nucleus and the cytosol as well. These results indicate that bioactive GA can be synthesized in the cytosol and the nucleus, two compartments where GA receptor GID1 exists. Furthermore, the D1 protein was found to be specifically expressed in the stamen primordia in the female floret, suggesting that the suppression of stamen development is mediated by locally synthesized GAs.
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[Pro731Ser mutation in the ?-myosin heavy chain and hypertrophic cardiomyopathy in a Chinese pedigree].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 10-21-2014
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To identify the casual mutation of a Chinese pedigree with hypertrophic cardiomyopathy (HCM), and to analyze the genotype-phenotype relationship.
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Suitable Depth of Epidural Puncture in Nulliparous Pregnant Woman.
Cell Biochem. Biophys.
PUBLISHED: 10-11-2014
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We study the suitable depth for epidural puncture in primiparas so as to decrease epidural complications and provide anesthesiologists with an appropriate insertion guide. A prospective study of 87 primipara patients receiving labor analgesia who had epidural punctures in the course of vaginal delivery were randomly divided into 3 groups: the L 3,4 group (N = 27), the L 2,3 group (N = 29), and the L 1,2 group (N = 26). Predictive statistical models were used for the formulation of the ideal epidural puncture needle depth. Eighty two patients who had non-traumatic epidural punctures were studied. There were no significant changes in age, weight, height, weight/height ratio, gestational weeks, fetus weight, pregnancy weight, weight difference, and fetus weight (P > 0.05). Compared with L 3,4 intervertebral space, the puncture depth in L 1,2 and L 2,3 was significantly shorter (P < 0.05) and (P < 0.001), respectively; Regression equation: PD (cm) = 0.351 [LHZ] + 0.147 [BMI] + 0.017. The correlation coefficient for LHZ was 0.351 (95 % CI 0.278-0.424; P < 0.001), the correlation coefficient for BMI was 0.147 (95 % CI 0.123-0.171; P < 0.001). This formula is accurate and practical with less complex calculations. However, further validation through a prospective study will be required. It is an accurate way to localize the puncture site in parturients and improve the efficiency of puncture in parturients for analgesia labor.Epidural puncture depth prediction in L 1,2, L 2,3, and L 3,4 can supply with a related reference.
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A TAK1 Signaling Pathway Critically Regulates Myocardial Survival and Remodeling.
Circulation
PUBLISHED: 10-04-2014
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-Programmed necrosis (necroptosis) plays an important role in development, tissue homeostasis, and disease pathogenesis. The molecular mechanisms that regulate necroptosis in the heart and its physiological relevance in myocardial remodeling and heart failure remain largely unknown.
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Targeting RNA transcription and translation in ovarian cancer cells with pharmacological inhibitor CDKI-73.
Oncotarget
PUBLISHED: 10-04-2014
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Dysregulation of cellular transcription and translation is a fundamental hallmark of cancer. As CDK9 and Mnks play pivotal roles in the regulation of RNA transcription and protein synthesis, respectively, they are important targets for drug development. We herein report the cellular mechanism of a novel CDK9 inhibitor CDKI-73 in an ovarian cancer cell line (A2780). We also used shRNA-mediated CDK9 knockdown to investigate the importance of CDK9 in the maintenance of A2780 cells. This study revealed that CDKI-73 rapidly inhibited cellular CDK9 kinase activity and down-regulated the RNAPII phosphorylation. This subsequently caused a decrease in the eIF4E phosphorylation by blocking Mnk1 kinase activity. Consistently, CDK9 shRNA was also found to down-regulate the Mnk1 expression. Both CDKI-73 and CDK9 shRNA decreased anti-apoptotic proteins Mcl-1 and Bcl-2 and induced apoptosis. The study confirmed that CDK9 is required for cell survival and that ovarian cancer may be susceptible to CDK9 inhibition strategy. The data also implied a role of CDK9 in eIF4E-mediated translational control, suggesting that CDK9 may have important implication in the Mnk-eIF4E axis, the key determinants of PI3K/Akt/mTOR- and Ras/Raf/MAPK-mediated tumorigenic activity. As such, CDK9 inhibitor drug candidate CDKI-73 should have a major impact on these pathways in human cancers.
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Characteristics of hip fracture patients with and without muscle atrophy/weakness: Predictors of negative economic outcomes.
J Med Econ
PUBLISHED: 10-02-2014
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Abstract Objective: Hip fractures have negative humanistic and economic consequences. Predictors and sub-groups of negative post-fracture outcomes (high costs and extensive healthcare utilization) were identified in patients with and without muscle atrophy/weakness (MAW). Methods: Truven Health MarketScan data identified patients ?50 years old with inpatient hospitalizations for hip fracture. Patients had ?12 months of continuous healthcare insurance prior to and following index hospitalization and no hip fracture diagnoses between 7 days and 1 year prior to admission. Predictors and sub-groups of negative outcomes were identified via multiple logistic regression analyses and classification and regression tree (CART) analyses, respectively. Results: Post-fracture 1-year all-cause healthcare costs (USD$31,430) were higher than costs for the prior year ($18,091; p?
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Giant Plasmene Nanosheets, Nanoribbons, and Origami.
ACS Nano
PUBLISHED: 10-02-2014
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We introduce Plasmene- in analogy to graphene-as free-standing, one-particle-thick, superlattice sheets of nanoparticles ("meta-atoms") from the "plasmonic periodic table", which has implications in many important research disciplines. Here, we report on a general bottom-up self-assembly approach to fabricate giant plasmene nanosheets (i.e., plasmene with nanoscale thickness but with macroscopic lateral dimensions) as thin as ?40 nm and as wide as ?3 mm, corresponding to an aspect ratio of ?75?000. In conjunction with top-down lithography, such robust giant nanosheets could be milled into one-dimensional nanoribbons and folded into three-dimensional origami. Both experimental and theoretical studies reveal that our giant plasmene nanosheets are analogues of graphene from the plasmonic nanoparticle family, simultaneously possessing unique structural features and plasmon propagation functionalities.
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[Effects of maternal age on pregnancy: a retrospective cohort study].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 09-26-2014
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To determine the pregnancy outcomes related with maternal age in China.
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[Development of new magnetic bead separation and purification instrument].
Zhongguo Yi Liao Qi Xie Za Zhi
PUBLISHED: 09-23-2014
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The article describes the development of new magnetic bead separation and purification instrument. The main application of the instrument is to capture tubercle bacillus from sputum. It is a pretreatment instrument and provides a new platform to help doctors to diagnose bacillary phthisis. Not only could it be used for tubercle bacillus capturing, but also for gene, protein and cell separating and purification. Because the controller of the instrument is 16-bit single chip microcomputer, the cost could be greatly reduced and it will be widely used in China.
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Novel Oligo(ethylene glycol)-Based Molecularly Imprinted Magnetic Nanoparticles for Thermally Modulated Capture and Release of Lysozyme.
ACS Appl Mater Interfaces
PUBLISHED: 09-22-2014
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In this study, oligo(ethylene glycol) (OEG)-based thermoresponsive molecularly imprinted polymers (MIPs) for lysozyme on the surface of magnetic nanoparticles were synthesized. Thermoresponsive monomer 2-(2-methoxyethoxy)ethyl methacrylate, chelate monomer N-(4-vinyl)-benzyl iminodiacetic acid, and acidic monomer methacrylic acid were selected as the ingredients for preparing the MIP layer. The thermoresponsive behavior of the novel imprinted magnetic nanoparticles was evaluated by dynamic light scattering and swelling ratios measurements. Interestingly, in analysis of lysozyme, the capture/release process could be modulated by changing the temperature, avoiding tedious washing steps. Meanwhile, high adsorption capacity (204.1 mg/g) and good selectivity for capturing lysozyme were achieved. Additionally, surface imprinting with magnetic nanoparticles as substrate allowed for short adsorption time (2 h) and rapid magnetic separation. Furthermore, the proposed imprinted magnetic nanoparticles were used to selectively extract lysozyme in human urine with recoveries ranging from 89.2% to 97.3%. The results indicated that the OEG-based monomers are promising for responsive MIP preparation, and the proposed imprinted material is efficient for thermally modulated capture and release of target protein.
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Preoperative risk score predicting 90-day mortality after liver resection in a population-based study.
Medicine (Baltimore)
PUBLISHED: 09-12-2014
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The impact of important preexisting comorbidities, such as liver and renal disease, on the outcome of liver resection remains unclear. Identification of patients at risk of mortality will aid in improving preoperative preparations. The purpose of this study is to develop and validate a population-based score based on available preoperative and predictable parameters predicting 90-day mortality after liver resection using data from a hepatitis endemic country.We identified 13,159 patients who underwent liver resection between 2002 and 2006 in the Taiwan National Health Insurance Research Database. In a randomly selected half of the total patients, multivariate logistic regression analysis was used to develop a prediction score for estimating the risk of 90-day mortality by patient demographics, preoperative liver disease and comorbidities, indication for surgery, and procedure type. The score was validated with the remaining half of the patients.Overall 90-day mortality was 3.9%. Predictive characteristics included in the model were age, preexisting cirrhosis-related complications, ischemic heart disease, heart failure, cerebrovascular disease, renal disease, malignancy, and procedure type. Four risk groups were stratified by mortality scores of 1.1%, 2.2%, 7.7%, and 15%. Preexisting renal disease and cirrhosis-related complications were the strongest predictors. The score discriminated well in both the derivation and validation sets with c-statistics of 0.75 and 0.75, respectively.This population-based score could identify patients at risk of 90-day mortality before liver resection. Preexisting renal disease and cirrhosis-related complications had the strongest influence on mortality. This score enables preoperative risk stratification, decision-making, quality assessment, and counseling for individual patients.
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Parkinson's disease patients with pain suffer from more severe non-motor symptoms.
Neurol. Sci.
PUBLISHED: 09-06-2014
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Non-motor symptoms, including pain, depression, sleep disorder, and olfactory dysfunction, occur frequently in patients with Parkinson's disease (PD), even before the onset of motor symptoms. Although studies have examined the correlation between pain and depression or sleep disorder in PD, few studies have investigated the correlation between pain and a range of other non-motor symptoms of PD. PD patients (n = 142) with or without pain were included in the study. PD severity was evaluated with the Unified Parkinson's Disease Rating Scale (UPDRS) and the Hoehn and Yahr (H/Y) staging scale. Pain severity was analyzed with the Visual Analog Scale. The Hamilton Rating Scale for Depression (HRSD; 24 items), Montreal Cognitive Assessment Beijing Version (MoCA), and non-motor questionnaire (NMSQT) measured symptoms of depression, cognitive function, and non-motor symptoms. The incidence of pain was 47.9 % in patients with PD, most of whom had moderate pain levels. Patients with pain showed higher HRSD, UPDRS, H/Y, and NMSQT scores and lower MoCA scores compared to those of patients without pain. HRSD and NMSQT scores were closely related with pain (P < 0.001). Non-motor symptoms were more prominent in patients with pain compared to that of controls and PD patients without pain.
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Redox Regulation of Inflammation: Old Elements, a New Story.
Med Res Rev
PUBLISHED: 08-29-2014
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Inflammation is an essential immune response characterized by pain, swelling, redness, heat, and impaired function. A controlled acute inflammatory response is necessary to fight off infection and overcome injury. However, if the inflammatory process persists and enters into the chronic state, it can lead to local and systemic deleterious effects counterproductive to healing and instead constitutes a new pathology. Typically, inflamed tissues are associated with an elevated level of reactive species (reactive oxygen species (ROS)/reactive nitrogen species (RNS)). These ROS/RNS are generated during the respiratory burst of immune cells and are important factors in defense against invading pathogens. Additionally, reactive species are now known to trigger oxidative/nitrosative modifications of biomolecules. While most of these modifications lead to irreparable damage, some are subtle and fully reversible. The reversible modifications can initiate signaling cascades known as "redox signaling." This redox signaling tightly modulates the inflammatory response. Thus, understanding the complex role of ROS/RNS-induced redox signaling in inflammation will assist in the design of relevant therapeutic intervention strategies for inflammation-associated diseases. This review will highlight the impact of oxidative stress and redox signaling on inflammation and inflammation-associated diseases, with a focus on redox modifications of inflammation-related proteins.
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Conditional knockout of the androgen receptor in gonadotropes reveals crucial roles for androgen in gonadotropin synthesis and surge in female mice.
Mol. Endocrinol.
PUBLISHED: 08-26-2014
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Polycystic ovary syndrome is the major cause of infertility in reproductive aged women. Polycystic ovary syndrome is associated with high circulating levels of androgens and impaired metabolic function. The goal of this study was to understand how androgen signaling via the androgen receptor (AR) affects reproductive function. We knocked out the AR gene specifically in pituitary gonadotropes (PitARKO) to explore the role of androgen on the development of reproductive function in female mice. There was no difference in the age of puberty between control and PitARKO littermates, which was assessed by the ages of vaginal opening and first estrus. Cyclicity and fertility were also studied, and there was no significant difference between control and PitARKO mice. We observed a significant decrease in basal FSH serum and mRNA levels with no corresponding change in LH serum and mRNA levels. Although the numbers of litters born to control and PitARKO females were the same, the litter size was significantly smaller for PitARKO mice. The LH and FSH responses to ovariectomy was altered with reduced LH/FSH hormone and mRNA levels in PitARKO females. This reduction may be due to reduced expression of activin A/B and gnrhr. The preovulatory surge levels of LH and FSH were dramatically lower in PitARKO mice. The number of corpora lutea was decreased whereas the number of antral follicles was similar between control and PitARKO mice. Overall the pituitary AR contributes to the elaboration of the LH surge and normal reproductive function by regulating LH/FSH expression and secretion.
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[Effect of compound qingqin liquid on the expression levels of ang II and COX-2 mRNA transcription and protein expression in the renal tissue of uric acid nephropathy rats: an experimental study].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 08-21-2014
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To investigate the effect of Compound Qingqin Liquid (CQL) on the expression level of angiotensin II (Ang II) and COX-2 mRNA transcription and protein expression in the renal tissue of rats with uric acid nephropathy.
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Persistent beneficial impact of H-reflex conditioning in spinal cord-injured rats.
J. Neurophysiol.
PUBLISHED: 08-20-2014
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Operant conditioning of a spinal cord reflex can improve locomotion in rats and humans with incomplete spinal cord injury. This study examined the persistence of its beneficial effects. In rats in which a right lateral column contusion injury had produced asymmetric locomotion, up-conditioning of the right soleus H-reflex eliminated the asymmetry while down-conditioning had no effect. After the 50-day conditioning period ended, the H-reflex was monitored for 100 [±9 (SD)] (range 79-108) more days and locomotion was then reevaluated. After conditioning ended in up-conditioned rats, the H-reflex continued to increase, and locomotion continued to improve. In down-conditioned rats, the H-reflex decrease gradually disappeared after conditioning ended, and locomotion at the end of data collection remained as impaired as it had been before and immediately after down-conditioning. The persistence (and further progression) of H-reflex increase but not H-reflex decrease in these spinal cord-injured rats is consistent with the fact that up-conditioning improved their locomotion while down-conditioning did not. That is, even after up-conditioning ended, the up-conditioned H-reflex pathway remained adaptive because it improved locomotion. The persistence and further enhancement of the locomotor improvement indicates that spinal reflex conditioning protocols might supplement current therapies and enhance neurorehabilitation. They may be especially useful when significant spinal cord regeneration becomes possible and precise methods for retraining the regenerated spinal cord are needed.
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Cronobacter: an emergent pathogen causing meningitis to neonates through their feeds.
Sci Prog
PUBLISHED: 08-12-2014
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The recognition of Cronobacter as a public health concern was raised when powdered infant formula (PIF) was linked to several neonatal meningitis outbreaks. It is an opportunistic pathogen that causes necrotising enterocolitis, infantile septicaemia, and meningitis which carries a high mortality rate among neonates. It has been also linked with cases of infection in adults and elderly. Over the past decade, much focus has been made on developing sensitive and specific characterisation, detection, and isolation methods to ascertain the quality of foods, notably contamination of PIF with Cronobacter and to understand its ability to cause disease. Whole genome sequencing has unveiled several putative virulence factors, yet the full capacity of the pathogenesis of Cronobacter has not yet been elucidated.
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Risk factors of depression after prolonged low-dose rate environmental radiation exposure.
Int. J. Radiat. Biol.
PUBLISHED: 08-11-2014
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More than 10,000 Taiwanese people were exposed to excessive protracted low-dose rate radiation from contaminated reinforcement bars, which were installed in buildings before 1992. This study was conducted to assess the prevalence of depression amongst the exposed and identify related determinants now that more than two decades have passed since this population was informed of their exposure to radiation.
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Sleep Apnea and the Risk of Chronic Kidney Disease: A Nationwide Population-Based Cohort Study.
Sleep
PUBLISHED: 08-06-2014
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Sleep apnea (SA) is characterized by apnea during sleep and is associated with cardiovascular diseases and an increase in all-cause mortality. Chronic kidney disease (CKD) is a global health problem that has placed a substantial burden on healthcare resources. However, the relationship between SA and the incidence of CKD is not clear. This study aimed to determine whether SA is an independent risk factor for the development of CKD.
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Construction of doxycycline-mediated BMP-2 transgene combining with APA microcapsules for bone repair.
Artif Cells Nanomed Biotechnol
PUBLISHED: 08-06-2014
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Objectives: The repairing of large segmental bone defects is difficult for clinical orthopedists at present. Gene therapy is regarded as a promising method for bone defects repair. The present study aimed to construct an effective and controllable Tet-On expression system for transferring hBMP-2 gene into bone marrow mesenchymal progenitor cells (BMSCs). Meanwhile, with combination of alginate-poly-L-lysine-alginate (APA) microencapsulation technology, we attempted to reduce the influence of immunologic rejection and examine the effect of the Tet-On expression system on osteogenesis of BMSCs. Methods: The adenovirus encoding hBMP-2 (ADV-hBMP2) was constructed using the means of molecular cloning. The ADV-hBMP2 and Adeno-X Tet-On virus was respectively transfected to the HEK293 for amplification and afterward BMSCs were co-infected with the virus of ADV-hBMP2 and the Adeno-X Tet-On. The expression of hBMP-2 was measured with induction by doxycycline (DOX) at different concentration by means of RT-PCR and ELISA. Combining Tet-On expression system and APA microcapsules with the use of the pulsed high-voltage electrostatic microcapsule instrument, we examined the expression level of hBMP-2 in APA microcapsules by ELISA as well as the osteogenesis by alizarin red S staining. Key findings: An effective Tet-On expression system for transferring hBMP-2 gene into BMSCs was constructed successfully. Also, the expression of hBMP-2 could be regulated by concentration of DOX. The data exhibited that BMSCs in APA microcapsules maintained the capability of proliferation and differentiation. The combination of Tet-On expression system and APA microcapsules could promote the osteogenesis of BMSCs. Conclusions: According to the results, microencapsulated Tet-On expression system showed the effective characteristics of secreting hBMP-2 and enhancing osteogenesis, which would provide a promising way for bone repair.
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Preterm birth and neonatal mortality in China in 2011.
Int J Gynaecol Obstet
PUBLISHED: 08-02-2014
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To determine the incidence of preterm birth, its regional distribution, and associated neonatal mortality in mainland China.
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Kinase domain inhibition of leucine rich repeat kinase 2 (LRRK2) using a [1,2,4]triazolo[4,3-b]pyridazine scaffold.
Bioorg. Med. Chem. Lett.
PUBLISHED: 07-30-2014
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Leucine rich repeat kinase 2 (LRRK2) has been genetically linked to Parkinson's disease (PD). The most common mutant, G2019S, increases kinase activity, thus LRRK2 kinase inhibitors are potentially useful in the treatment of PD. We herein disclose the structure, potential ligand-protein binding interactions, and pharmacological profiling of potent and highly selective kinase inhibitors based on a triazolopyridazine chemical scaffold.
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A digitally assisted, signal folding neural recording amplifier.
IEEE Trans Biomed Circuits Syst
PUBLISHED: 07-30-2014
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A novel signal folding and reconstruction scheme for neural recording applications that exploits the 1/f(n) characteristics of neural signals is described in this paper. The amplified output is 'folded' into a predefined range of voltages by using comparison and reset circuits along with the core amplifier. After this output signal is digitized and transmitted, a reconstruction algorithm can be applied in the digital domain to recover the amplified signal from the folded waveform. This scheme enables the use of an analog-to-digital convertor with less number of bits for the same effective dynamic range. It also reduces the transmission data rate of the recording chip. Both of these features allow power and area savings at the system level. Other advantages of the proposed topology are increased reliability due to the removal of pseudo-resistors, lower harmonic distortion and low-voltage operation. An analysis of the reconstruction error introduced by this scheme is presented along with a behavioral model to provide a quick estimate of the post reconstruction dynamic range. Measurement results from two different core amplifier designs in 65 nm and 180 nm CMOS processes are presented to prove the generality of the proposed scheme in the neural recording applications. Operating from a 1 V power supply, the amplifier in 180 nm CMOS has a gain of 54.2 dB, bandwidth of 5.7 kHz, input referred noise of 3.8 ?Vrms and power dissipation of 2.52 ?W leading to a NEF of 3.1 in spike band. It exhibits a dynamic range of 66 dB and maximum SNDR of 43 dB in LFP band. It also reduces system level power (by reducing the number of bits in the ADC by 2) as well as data rate to 80% of a conventional design. In vivo measurements validate the ability of this amplifier to simultaneously record spike and LFP signals.
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[Recent advancement of photonic-crystal-based analytical chemistry].
Se Pu
PUBLISHED: 07-30-2014
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Photonic crystals are a type of novel materials with ordered structure, nanopores/channels and optical band gap. They have hence important applications in physics, chemistry, biological science and engineering fields. This review summarizes the recent advancement of photonic crystals in analytical chemistry applications, with focus on sensing and separating fields happening in the nearest 5 years.
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Preparation of a novel polymer monolith with functional polymer brushes by two-step atom-transfer radical polymerization for trypsin immobilization.
J Sep Sci
PUBLISHED: 07-23-2014
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Novel porous polymer monoliths grafted with poly{oligo[(ethylene glycol) methacrylate]-co-glycidyl methacrylate} brushes were fabricated via two-step atom-transfer radical polymerization and used as a trypsin-based reactor in a continuous flow system. This is the first time that atom-transfer radical polymerization technique was utilized to design and construct polymer monolith bioreactor. The prepared monoliths possessed excellent permeability, providing fast mass transfer for enzymatic reaction. More importantly, surface properties, which were modulated via surface-initiated atom-transfer radical polymerization, were found to have a great effect on bioreactor activities based on Michaelis-Menten studies. Furthermore, three model proteins were digested by the monolith bioreactor to a larger degree within dramatically reduced time (50 s), about 900 times faster than that by free trypsin (12 h). The proposed method provided a platform to prepare porous monoliths with desired surface properties for immobilizing various enzymes.
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United Iterative Reconstruction for Spectral Computed Tomography.
IEEE Trans Med Imaging
PUBLISHED: 07-23-2014
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Spectral computed tomography (CT) has attracted considerable attention because of its energy-resolving capability in identifying and discriminating materials. The use of a narrow energy bin can improve energy resolution. However, a narrow energy bin has high noise ratio, which degrades the imaging quality of spectral CT. To address this problem, this study exploits the structure correlations of images in the energy domain and proposed two types of united iterative reconstruction (UIR) algorithms. One type uses the well-reconstructed broad-spectrum image, with all available photons, as a constraint, whereas the other type uses a pseudo narrow-energy image, which is estimated with the use of our proposed structure-coupling (SC) method, as a constraint. The SC method utilizes local structures to connect images that are reconstructed with broad-spectrum and narrow-energy CT datasets. Given a broad-spectrum image, the SC method can accurately estimate its corresponding narrow-energy image. Results show that UIR algorithms significantly outperform conventional iterative reconstruction algorithms for narrow-energy image reconstruction in spectral CT. Among the UIR algorithms, SC-UIR yields the best results.
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[Effect of compound qingqin liquid on the expression of toll-like receptor in the renal tissue of rats with urate nephropathy].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 07-23-2014
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To investigate the effect of compound qingqin liquid (CQL) on Toll-like receptor 2 (TLR2) and toll-like receptor 4 (TLR4) in rats with urate nephropathy, and to explore its renal protection mechanism.
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[Effect of yiqi huaju recipe combined with routine therapy in treating hypertension patients with metabolic syndrome: a clinical study].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 07-23-2014
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To investigate the therapeutic effect of Yiqi Huaju Recipe (YHR) combined with routine therapy on the blood pressure, the blood pressure variability and other cardiovascular risk factors in hypertension patients complicated with metabolic syndrome (MetS).
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Combined hydrolysis acidification and bio-contact oxidation system with air-lift tubes and activated carbon bioreactor for oilfield wastewater treatment.
Bioresour. Technol.
PUBLISHED: 07-21-2014
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This paper investigated the enhancement of the COD reduction of an oilfield wastewater treatment process by installing air-lift tubes and adding an activated carbon bioreactor (ACB) to form a combined hydrolysis acidification and bio-contact oxidation system with air-lift tubes (HA/air-lift BCO) and an ACB. Three heat-resistant bacterial strains were cultivated and subsequently applied in above pilot plant test. Installing air-lift tubes in aerobic tanks reduced the necessary air to water ratio from 20 to 5. Continuous operation of the HA/air-lift BCO system for 2 months with a hydraulic retention time of 36 h, a volumetric load of 0.14 kg COD/(m(3)d) (hydrolysis-acidification or anaerobic tank), and 0.06 kg COD/(m(3)d) (aerobic tanks) achieved an average reduction of COD by 60%, oil and grease by 62%, total suspended solids by 75%, and sulfides by 77%. With a COD load of 0.56 kg/(m(3)d), the average COD in the ACB effluent was 58 mg/L.
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Controlled Synthesis of Multilayered Gold Nanoshells for Enhanced Photothermal Therapy and SERS Detection.
Small
PUBLISHED: 07-20-2014
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It can be streamlined: A facile and controllable approach for the fabrication of core/shell-structured multilayer gold nanoshells with uniform nanosize, monodispersity, and tunable plasmonic properties has been successfully developed by utilizing an organosilica layer as the dielectric spacer layer.
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Simultaneous determination of electrophoretic and dielectrophoretic mobilities of human red blood cells.
Electrophoresis
PUBLISHED: 07-17-2014
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Electrophoresis and dielectrophoresis of cells can reveal many distinct cellular properties but are often conducted separately. Herein a simultaneous strategy was proposed, and a simple method was established by making cells migrate through a cross channel under a micro video for real-time observation. The experiment can be performed within 0.044-1s. In combination with digital calculation based on electromagnetic theory, the method was validated to be applicable to the determination of electrophoretic and dielectrophoretic mobilities, ?EP and ?DEP , of human blood erythrocytes, giving ?EP = - (0.87±0.16)×10(-4) cm(2) · V(-1) · s(-1) and ?DEP = - (4.5±1.3)×10(-8) cm(4) · V(-2) · s(-1) by vector decomposition, or ?EP = - (0.89±0.14)×10(-4) cm(2) · V(-1) · s(-1) and ?DEP = - (4.6±1.2)×10(-8) cm(4) · V(-2) · s(-1) by least squares fitting, all agreeing with published data. Hydrodynamic and electroosmotic flows were eliminated for better measurement. It was found that the location of cells had a serious impact on the measurement precision, and the upstream of the cross channel along the electric field was chosen for precise measurement. The method is also extendable to the study of other cells and particles. This article is protected by copyright. All rights reserved.
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Gliomatosis cerebri mimicking acute viral encephalitis and with malignant transformation of partial lesions: A case report.
Exp Ther Med
PUBLISHED: 06-24-2014
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Gliomatosis cerebri (GC) is a rare glial neoplasm, characterized by extensive diffuse brain infiltration and relative preservation of the underlying architecture. In the present case report, a patient with type 2 GC, which mimicked the clinicoradiological course of acute viral encephalitis, is presented. A 56-year-old male presented with fever, dizziness, headache and numbness in the right extremities three days prior to admission to hospital. The cerebrospinal fluid (CSF) showed mild pleocytosis. Brain magnetic resonance imaging (MRI) revealed hyperintensity on fluid-attenuated inversion recovery images in the left frontal, temporal, insular lobes and in the left thalamus. No signal enhancement was observed following gadolinium administration. The patient was diagnosed with acute viral encephalitis of unknown cause and received a 10-day course of acyclovir, intravenously. At the follow-up three months later, the patient had personality changes and memory deterioration. The results from the follow-up MRI revealed no remarkable changes. At the follow-up six months after presentation, the patient had expressive aphasia and severe headaches. Subsequently, the patient had two tonic-clonic seizure onsets. The results from the MRI showed an increase in lesion size, more edema around the lesion and irregular enhancement in the left frontal lobe. However, the lesions in the left temporal and insular lobes and in the left thalamus were nearly unchanged. Magnetic resonance spectroscopy (MRS) showed elevated choline (Cho)/creatine (Cr) and Cho/N-acetylaspartate (NAA) ratios, as well as decreased NAA/Cr ratios. Surgery was performed and the neuropathological diagnosis of WHO grade III astrocytoma was confirmed. Thus, it is important to pay attention to the differential diagnoses of GC and acute viral encephalitis in patients who have widespread MRI lesions. A brain biopsy is recommended for a diagnosis in this case.
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Effects of parathyroid hormone on calcium ions in rat bone marrow mesenchymal stem cells.
Biomed Res Int
PUBLISHED: 06-18-2014
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The present study was conducted in order to explore the mechanisms whereby parathyroid hormone (PTH) maintains in vitro proliferation of bone marrow mesenchymal stem cells (BMSCs). Bone marrow was isolated from Sprague Dawley (SD) rat femurs, cultured in vitro, and passaged using a cell adherent culture method. The BMSC proliferation was evaluated by the methyl thiazolyl tetrazolium (MTT) assay and the fluorescence intensity of calcium ions in BMSCs was analyzed by laser scanning confocal microscopy (LSCM). Our results show that BMSC proliferation in the experimental group treated with PTH was more significant than controls. The calcium ion fluorescence intensity in BMSCs was significantly higher for the experimental group as compared to the control group. For each group, there was significant difference in the fluorescence intensity of calcium ions in BMSCs between 7?d and 14?d. In conclusion, parathyroid hormone increased the fluorescence intensity of calcium ions in BMSCs, which might represent a key mechanism whereby BMSC proliferation is maintained.
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Development of a universal metabolome-standard method for long-term LC-MS metabolome profiling and its application for bladder cancer urine-metabolite-biomarker discovery.
Anal. Chem.
PUBLISHED: 06-10-2014
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Large-scale metabolomics study requires a quantitative method to generate metabolome data over an extended period with high technical reproducibility. We report a universal metabolome-standard (UMS) method, in conjunction with chemical isotope labeling liquid chromatography-mass spectrometry (LC-MS), to provide long-term analytical reproducibility and facilitate metabolome comparison among different data sets. In this method, UMS of a specific type of sample labeled by an isotope reagent is prepared a priori. The UMS is spiked into any individual samples labeled by another form of the isotope reagent in a metabolomics study. The resultant mixture is analyzed by LC-MS to provide relative quantification of the individual sample metabolome to UMS. UMS is independent of a study undertaking as well as the time of analysis and useful for profiling the same type of samples in multiple studies. In this work, the UMS method was developed and applied for a urine metabolomics study of bladder cancer. UMS of human urine was prepared by (13)C2-dansyl labeling of a pooled sample from 20 healthy individuals. This method was first used to profile the discovery samples to generate a list of putative biomarkers potentially useful for bladder cancer detection and then used to analyze the verification samples about one year later. Within the discovery sample set, three-month technical reproducibility was examined using a quality control sample and found a mean CV of 13.9% and median CV of 9.4% for all the quantified metabolites. Statistical analysis of the urine metabolome data showed a clear separation between the bladder cancer group and the control group from the discovery samples, which was confirmed by the verification samples. Receiver operating characteristic (ROC) test showed that the area under the curve (AUC) was 0.956 in the discovery data set and 0.935 in the verification data set. These results demonstrated the utility of the UMS method for long-term metabolomics and discovering potential metabolite biomarkers for diagnosis of bladder cancer.
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Changes in coagulation and fibrinolytic indices in women with polycystic ovarian syndrome undergoing controlled ovarian hyperstimulation.
Int J Endocrinol
PUBLISHED: 05-26-2014
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Background. Polycystic ovarian syndrome (PCOS) women undergoing in vitro fertilization and embryo transfer (IVF-ET) treatment always attain a low cumulative pregnancy rate disaccording with the satisfactory number of oocytes. Objective. We aim to evaluate the status of coagulation and fibrinolytic system in PCOS patients undergoing controlled ovarian hyperstimulation (COH) process. Method. Of the 97 women, 30 patients with PCOS composed the study group; 67 women of child-bearing age with normal endocrine function composed the control group. All participants underwent GnRH agonist standard long protocol, and plasma HCY, FVIII, FX, and D-dimer levels as well as hormone parameters were measured at day of full downregulation, hCG priming, and embryos transfer. Results. On day of full downregulation, FX levels were significantly higher in PCOS group (P < 0.01). On hCG priming day, FX and estrogen levels in PCOS group were higher than in the control group and FVIII levels were significantly lower on day of embryos transfer whereas FX and E2 levels were significantly higher in PCOS group. Conclusion. Hypercoagulable state during peri-implantation phase would probably lead to poor microcirculation of endometrium and be one of the most important disadvantages of successful implantation and subsequent clinical pregnancy.
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Lineage Tracing Reveals Distinctive Fates for Mesothelial Cells and Submesothelial Fibroblasts during Peritoneal Injury.
J. Am. Soc. Nephrol.
PUBLISHED: 05-24-2014
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Fibrosis of the peritoneal cavity remains a serious, life-threatening problem in the treatment of kidney failure with peritoneal dialysis. The mechanism of fibrosis remains unclear partly because the fibrogenic cells have not been identified with certainty. Recent studies have proposed mesothelial cells to be an important source of myofibroblasts through the epithelial-mesenchymal transition; however, confirmatory studies in vivo are lacking. Here, we show by inducible genetic fate mapping that type I collagen-producing submesothelial fibroblasts are specific progenitors of ?-smooth muscle actin-positive myofibroblasts that accumulate progressively in models of peritoneal fibrosis induced by sodium hypochlorite, hyperglycemic dialysis solutions, or TGF-?1. Similar genetic mapping of Wilms' tumor-1-positive mesothelial cells indicated that peritoneal membrane disruption is repaired and replaced by surviving mesothelial cells in peritoneal injury, and not by submesothelial fibroblasts. Although primary cultures of mesothelial cells or submesothelial fibroblasts each expressed ?-smooth muscle actin under the influence of TGF-?1, only submesothelial fibroblasts expressed ?-smooth muscle actin after induction of peritoneal fibrosis in mice. Furthermore, pharmacologic inhibition of the PDGF receptor, which is expressed by submesothelial fibroblasts but not mesothelial cells, attenuated the peritoneal fibrosis but not the remesothelialization induced by hypochlorite. Thus, our data identify distinctive fates for injured mesothelial cells and submesothelial fibroblasts during peritoneal injury and fibrosis.
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Overexpression of microRNA-124 promotes the neuronal differentiation of bone marrow-derived mesenchymal stem cells.
Neural Regen Res
PUBLISHED: 05-23-2014
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microRNAs (miRNAs) play an important regulatory role in the self-renewal and differentiation of stem cells. In this study, we examined the effects of miRNA-124 (miR-124) overexpression in bone marrow-derived mesenchymal stem cells. In particular, we focused on the effect of overexpression on the differentiation of bone marrow-derived mesenchymal stem cells into neurons. First, we used GeneChip technology to analyze the expression of miRNAs in bone marrow-derived mesenchymal stem cells, neural stem cells and neurons. miR-124 expression was substantially reduced in bone marrow-derived mesenchymal stem cells compared with the other cell types. We constructed a lentiviral vector overexpressing miR-124 and transfected it into bone marrow-derived mesenchymal stem cells. Intracellular expression levels of the neuronal early markers ?-III tubulin and microtubule-associated protein-2 were significantly increased, and apoptosis induced by oxygen and glucose deprivation was reduced in transfected cells. After miR-124-transfected bone marrow-derived mesenchymal stem cells were transplanted into the injured rat spinal cord, a large number of cells positive for the neuronal marker neurofilament-200 were observed in the transplanted region. The Basso-Beattie-Bresnahan locomotion scores showed that the motor function of the hind limb of rats with spinal cord injury was substantially improved. These results suggest that miR-124 plays an important role in the differentiation of bone marrow-derived mesenchymal stem cells into neurons. Our findings should facilitate the development of novel strategies for enhancing the therapeutic efficacy of bone marrow-derived mesenchymal stem cell transplantation for spinal cord injury.
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Targeted proteomics pipeline reveals potential biomarkers for the diagnosis of metastatic lung cancer in pleural effusion.
J. Proteome Res.
PUBLISHED: 05-14-2014
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The ability to discriminate lung cancer malignant pleural effusion (LC-MPE) from benign pleural effusion has profound implications for the therapy and prognosis of lung cancer. Here, we established a pipeline to verify potential biomarkers for this purpose. In the discovery phase, label-free quantification was performed for the proteome profiling of exudative pleural effusion in order to select 34 candidate biomarkers with significantly elevated levels in LC-MPE. In the verification phase, signature peptides for 34 candidates were first confirmed by accurate inclusion mass screening (AIMS). To quantify the candidates in PEs, multiple reaction monitoring mass spectrometry (MRM-MS) with stable isotope-labeled standards (SIS) peptides was performed for the 34 candidate biomarkers using the QconCAT approach for the generation of the SIS peptides. The results of the MRM assay were used to prioritize candidates based on their discriminatory power in 82 exudative PE samples. The five potential biomarkers (ALCAM, CDH1, MUC1, SPINT1, and THBS4; AUC > 0.7) and one three-marker panel (SPINT1/SVEP1/THBS4; AUC = 0.95) were able to effectively differentiate LC-MPE from benign PE. Collectively, these results demonstrate that our pipeline is a feasible platform for verifying potential biomarkers for human diseases.
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Pectin from Abelmoschus esculentus: optimization of extraction and rheological properties.
Int. J. Biol. Macromol.
PUBLISHED: 05-13-2014
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Response surface methodology (RSM) was applied to optimize the parameters of pectin extraction from okra pods. The extracted okra pectin was then investigated by steady-shear and oscillatory rheological measurements. Statistical analysis showed that the linear term of the liquid-solid ratio, the quadratic term of the pH, and the linear term of the extraction time showed highly significant effects on pectin yield. The optimal extraction conditions that maximized the pectin yield within the experimental range of the variables researched were a pH of 3.9, an extraction time of 64 min, an extraction temperature of 60°C, and a liquid-solid ratio of 42:1. Under these conditions, the pectin yield was predicted to be 2.71%. At a liquid-solid ratio less than 2.5% w/w in aqueous solution, the pectin extracted from okra presented non-Newtonian shear-thinning behavior and could be well described by the Cross model. The okra pectin showed predominantly viscous responses (G'
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Cross sectional study in China: fetal gender has adverse perinatal outcomes in mainland China.
BMC Pregnancy Childbirth
PUBLISHED: 05-12-2014
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BackgroundThe association between fetal gender and pregnancy outcomes has been thoroughly demonstrated in western populations. However, this association has not been thoroughly documented in China. The primary objective of the present study is to determine whether the association of adverse pregnancy and labour outcomes with male fetuses applies to the Chinese population.MethodsThis cross-sectional hospital-based retrospective survey collected data from thirty-nine hospitals in 2011 in mainland China. A total of 109,722 women with singleton pregnancy who delivered after 28 weeks of gestation were included.ResultsOf these pregnancies, the male-to-female sex ratio was 1.2. The rates of preterm birth (7.3% for males, 6.5% for females) and fetal macrosomia (8.3% for males, 5.1% for females) were higher for male newborns, whereas fetal growth restriction (8.0% for females, 5.4% for males) and malpresentation (4.3% for females, 3.6% for males) were more frequent among female-bearing mothers. A male fetus was associated with an increased incidence of operative vaginal delivery (1.3% for males, 1.1% for females), caesarean delivery (55.0% for males, 52.9% for females), and cephalopelvic disproportion/failure to progress (10.0% for males, 9.2% for female). Male gender was also significantly associated with lower Apgar scores (<7 at 5 min, adjusted odds ratio 1.3, 95% CI 1.0-1.6), as well as a neonatal intensive care unit admission and neonatal death, even after adjustments for confounders (adjusted odds ratio 1.3, 95% CI 1.1-1.5, adjusted odds ratio 1.4, 95% CI 1.1-1.8).ConclusionWe confirm the existence of obvious neonatal gender bias and adverse outcomes for male fetuses during pregnancy and labour in our population. Further research is required to understand the mechanisms and clinical implications of this phenomenon.
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Dynamic variability of the heading-flowering stages of single rice in China based on field observations and NDVI estimations.
Int J Biometeorol
PUBLISHED: 05-08-2014
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Although many studies have indicated the consistent impact of warming on the natural ecosystem (e.g., an early flowering and prolonged growing period), our knowledge of the impacts on agricultural systems is still poorly understood. In this study, spatiotemporal variability of the heading-flowering stages of single rice was detected and compared at three different scales using field-based methods (FBMs) and satellite-based methods (SBMs). The heading-flowering stages from 2000 to 2009 with a spatial resolution of 1 km were extracted from the SPOT/VGT NDVI time series data using the Savizky-Golay filtering method in the areas in China dominated by single rice of Northeast China (NE), the middle-lower Yangtze River Valley (YZ), the Sichuan Basin (SC), and the Yunnan-Guizhou Plateau (YG). We found that approximately 52.6 and 76.3 % of the estimated heading-flowering stages by a SBM were within ±5 and ±10 days estimation error (a root mean square error (RMSE) of 8.76 days) when compared with those determined by a FBM. Both the FBM data and the SBM data had indicated a similar spatial pattern, with the earliest annual average heading-flowering stages in SC, followed by YG, NE, and YZ, which were inconsistent with the patterns reported in natural ecosystems. Moreover, diverse temporal trends were also detected in the four regions due to different climate conditions and agronomic factors such as cultivar shifts. Nevertheless, there were no significant differences (p?>?0.05) between the FBM and the SBM in both the regional average value of the phenological stages and the trends, implying the consistency and rationality of the SBM at three scales.
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Regulation and actions of activin A and follistatin in myocardial ischaemia-reperfusion injury.
Cytokine
PUBLISHED: 04-13-2014
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Activin A, a member of the transforming growth factor-? superfamily, is stimulated early in inflammation via the Toll-like receptor (TLR) 4 signalling pathway, which is also activated in myocardial ischaemia-reperfusion. Neutralising activin A by treatment with the activin-binding protein, follistatin, reduces inflammation and mortality in several disease models. This study assesses the regulation of activin A and follistatin in a murine myocardial ischaemia-reperfusion model and determines whether exogenous follistatin treatment is protective against injury. Myocardial activin A and follistatin protein levels were elevated following 30 min of ischaemia and 2h of reperfusion in wild-type mice. Activin A, but not follistatin, gene expression was also up-regulated. Serum activin A did not change significantly, but serum follistatin decreased. These responses to ischaemia-reperfusion were absent in TLR4(-/-) mice. Pre-treatment with follistatin significantly reduced ischaemia-reperfusion induced myocardial infarction. In mouse neonatal cardiomyocyte cultures, activin A exacerbated, while follistatin reduced, cellular injury after 3h of hypoxia and 2h of re-oxygenation. Neither activin A nor follistatin affected hypoxia-reoxygenation induced reactive oxygen species production by these cells. However, activin A reduced cardiomyocyte mitochondrial membrane potential, and follistatin treatment ameliorated the effect of hypoxia-reoxygenation on cardiomyocyte mitochondrial membrane potential. Taken together, these data indicate that myocardial ischaemia-reperfusion, through activation of TLR4 signalling, stimulates local production of activin A, which damages cardiomyocytes independently of increased reactive oxygen species. Blocking activin action by exogenous follistatin reduces this damage.
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Hierarchical structure and mechanical properties of remineralized dentin.
J Mech Behav Biomed Mater
PUBLISHED: 04-10-2014
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It is widely accepted that the mechanical properties of dentin are significantly determined by its hierarchical structure. The current correlation between the mechanical properties and the hierarchical structure was mainly established by studying altered forms of dentin, which limits the potential outcome of the research. In this study, dentins with three different hierarchical structures were obtained via two different remineralization procedures and at different remineralization stages: (1) a dentin structure with amorphous minerals incorporated into the collagen fibrils, (2) a dentin with crystallized nanominerals incorporated into the collagen fibrils, and (3) a dentin with an out-of-order mineral layer filling the collagen fibrils matrix. Nanoindentation tests were performed to investigate the mechanical behavior of the remineralized dentin slides. The results showed that the incorporation of the crystallized nanominerals into the acid-etched demineralized organic fibrils resulted in a remarkable improvement of the mechanical properties of the dentin. In contrast, for the other two structures, i.e. the amorphous minerals inside the collagen fibrils and the out-of-order mineral layer within the collagen fibrils matrix, the excellent mechanical properties of dentin could not be restored.
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Xuebijing attenuates hypotension through the upregulation of angiotensin II type 1 receptor?associated protein 1 in rats suffering from heat stroke.
Int. J. Mol. Med.
PUBLISHED: 04-05-2014
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In our previous study, we demonstrated that Xuebijing (XBJ), a traditional Chinese medicine, attenuates hypotension in rats suffering from heatstroke (HS). However, the underlying mechanisms have not yet been fully elucidated. Thus, the current study was carried out to investigate the mechanisms underlying the effects of XBJ on hypotension n rats suffering from HS. For this purpose, 72 anesthetized rats were randomized into 3 groups and intravenously injected twice daily for 3 days with XBJ (4 ml/kg body weight, XBJ group) or phosphate?buffered saline (PBS) (HS and sham-operated groups). Models of HS were established in the HS and XBJ groups by placing the rats in a simulated climate chamber with a temperature of 40?C and a humidity of 60%. Rectal temperature, arterial pressure and heart rate were monitored and recorded. Angiotensin ? (Ang ?) levels were increased during HS (shown by ELISA), and XBJ had no apparent effect on Ang ? levels. The levels of Ang ? type 1 (AT1) receptor surface expression and AT1 receptor?associated protein 1 (Arap1) were decreased during HS; however, these effects were attenuated by pre-treatment with XBJ (shown by RT-qPCR and western blot analysis). For in vitro experiments, rat macrophages pre-treated with XBJ were stimulated with lipopolysaccharide (LPS). Pre-treatment with XBJ induced a marked inhibitory effect on the release of pro-inflammatory cytokines in the LPS?stimulated macrophages. Furthermore, XBJ inhibited the activation of nuclear factor ?B (NF??B) induced by LPS in the macrophages. Taken together, our data demonstrate that XBJ promotes Arap1 expression by inhibiting the activation of the NF??B signaling pathway and the release of pro-inflammatory cytokines, which may be the molecular mechanisms through which XBJ alleviates blood pressure reduction in rats suffering from HS.
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Cystatin C as a Predictor for Outcomes in Patients with Negligible Renal Function.
Blood Purif.
PUBLISHED: 04-03-2014
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Background: High serum cystatin C (CysC) has been associated with clinical risks independently of the glomerular filtration rate (GFR). This study aims to investigate the predictive power of CysC in patients with a negligible GFR. Methods: Patients on chronic hemodialysis or peritoneal dialysis were enrolled for measurement of CysC levels and were followed up for one year. A daily urine amount <100 ml was considered negligible residual renal function (RRF). Results: CysC results were available in 183 dialysis patients. Of these, 131 patients had a negligible RRF. The multivariate Cox proportional hazards model showed that CysC was an independent predictor of fatal and nonfatal cardiovascular and infection events in all dialysis patients and in dialysis patients with a negligible RRF. Conclusion: CysC maintained its predictive power for adverse outcomes in patients with no meaningful GFR, indicating that the prognostic value of CysC is independent of the GFR. © 2014 S. Karger AG, Basel.
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Monoamine oxidase A mediates prostate tumorigenesis and cancer metastasis.
J. Clin. Invest.
PUBLISHED: 04-03-2014
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Tumors from patients with high-grade aggressive prostate cancer (PCa) exhibit increased expression of monoamine oxidase A (MAOA), a mitochondrial enzyme that degrades monoamine neurotransmitters and dietary amines. Despite the association between MAOA and aggressive PCa, it is unclear how MAOA promotes PCa progression. Here, we found that MAOA functions to induce epithelial-to-mesenchymal transition (EMT) and stabilize the transcription factor HIF1?, which mediates hypoxia through an elevation of ROS, thus enhancing growth, invasiveness, and metastasis of PCa cells. Knockdown and overexpression of MAOA in human PCa cell lines indicated that MAOA induces EMT through activation of VEGF and its coreceptor neuropilin-1. MAOA-dependent activation of neuropilin-1 promoted AKT/FOXO1/TWIST1 signaling, allowing FOXO1 binding at the TWIST1 promoter. Importantly, the MAOA-dependent HIF1?/VEGF-A/FOXO1/TWIST1 pathway was activated in high-grade PCa specimens, and knockdown of MAOA reduced or even eliminated prostate tumor growth and metastasis in PCa xenograft mouse models. Pharmacological inhibition of MAOA activity also reduced PCa xenograft growth in mice. Moreover, high MAOA expression in PCa tissues correlated with worse clinical outcomes in PCa patients. These findings collectively characterize the contribution of MAOA in PCa pathogenesis and suggest that MAOA has potential as a therapeutic target in PCa.
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G226, a novel epipolythiodioxopiperazine derivative, induces autophagy and caspase-dependent apoptosis in human breast cancer cells in vitro.
Acta Pharmacol. Sin.
PUBLISHED: 03-21-2014
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To investigate the effects of G226, a novel epipolythiodioxopiperazine derivative, on human breast cancer cells in vitro, and to explore its anticancer mechanisms.
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Near-infrared fluorescence imaging of cancer mediated by tumor hypoxia and HIF1?/OATPs signaling axis.
Biomaterials
PUBLISHED: 03-17-2014
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Near-infrared fluorescence (NIRF) imaging agents are promising tools for noninvasive cancer imaging. Here, we explored the mechanistic properties of a specific group of NIR heptamethine carbocyanines including MHI-148 dye we identified and synthesized, and demonstrated these dyes to achieve cancer-specific imaging and targeting via a hypoxia-mediated mechanism. We found that cancer cells and tumor xenografts exhibited hypoxia-dependent MHI-148 dye uptake in vitro and in vivo, which was directly mediated by hypoxia-inducible factor 1? (HIF1?). Microarray analysis and dye uptake assay further revealed a group of hypoxia-inducible organic anion-transporting polypeptides (OATPs) responsible for dye uptake, and the correlation between OATPs and HIF1? was manifested in progressive clinical cancer specimens. Finally, we demonstrated increased uptake of MHI-148 dye in situ in perfused clinical tumor samples with activated HIF1?/OATPs signaling. Our results establish these NIRF dyes as potential tumor hypoxia-dependent cancer-targeting agents and provide a mechanistic rationale for continued development of NIRF imaging agents for improved cancer detection, prognosis and therapy.
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National HIV/AIDS mortality, prevalence, and incidence rates are associated with the Human Development Index.
Am J Infect Control
PUBLISHED: 03-01-2014
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HIV/AIDS is a worldwide threat to human health with mortality, prevalence, and incidence rates varying widely. We evaluated the association between the global HIV/AIDS epidemic and national socioeconomic development.
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Shorter daily dwelling time in peritoneal dialysis attenuates the epithelial-to-mesenchymal transition of mesothelial cells.
BMC Nephrol
PUBLISHED: 02-14-2014
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Peritoneal dialysis (PD) therapy is known to induce morphological and functional changes in the peritoneal membrane. Long-term exposure to conventional bio-incompatible dialysate and peritonitis is the main etiology of inflammation. Consequently, the peritoneal membrane undergoes structural changes, including angiogenesis, fibrosis, and hyalinizing vasculopathy, which ultimately results in technique failure. The epithelial-to-mesenchymal transition (EMT) of mesothelial cells (MCs) plays an important role during the above process; however, the clinical parameters associated with the EMT process of MCs remain to be explored.
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Red emissive cross-linked chitosan and their nanoparticles for imaging the nucleoli of living cells.
Carbohydr Polym
PUBLISHED: 02-11-2014
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Biocompatible glutaraldehyde-cross-linked chitosan with new red fluorescence were prepared for the first time and were shaped into nanoparticles via inverse-microemulsion method. They could luminesce at ca. 670 nm either as powders and nanoparticles or in real and gelling solutions or suspensions, having a lifetime of 1.353 ns and a quantum yield of 0.08 in solution or 0.01 in solid state. The new-formed pyridinium structures and the intramolecular charge transfer effect are considered to be responsible for the new red emission, which have been proved by FTIR, (13)C NMR, and some calculation using Gaussian 09, respectively. Strikingly, they are quite inert and anti-photobleaching, with only <3% loss of fluorescent intensity per minute in average under a continuous laser illumination at 633 nm and 50 ?W. Especially, their nanoparticles (5.6 nm) could enter into the negative nucleoli of living HeLa cells with low cytotoxicity for high contrast imaging inspections.
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Angiopoietin-2-induced arterial stiffness in CKD.
J. Am. Soc. Nephrol.
PUBLISHED: 02-07-2014
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The mechanism of vascular calcification in CKD is not understood fully, but may involve collagen deposition in the arterial wall upon osteo/chondrocytic transformation of vascular smooth muscle cells (VSMCs). Increased levels of circulating angiopoietin-2 correlate with markers of CKD progression and angiopoietin-2 regulate inflammatory responses, including intercellular and vascular adhesion and recruitment of VSMCs. Here, we investigate the potential role of angiopoietin-2 in the pathogenesis of arterial stiffness associated with CKD. In a cohort of 416 patients with CKD, the plasma level of angiopoietin-2 correlated independently with the severity of arterial stiffness assessed by pulse wave velocity. In mice subjected to 5/6 subtotal nephrectomy or unilateral ureteral obstruction, plasma levels of angiopoietin-2 also increased. Angiopoietin-2 expression markedly increased in tubular epithelial cells of fibrotic kidneys but decreased in other tissues, including aorta and lung, after 5/6 subtotal nephrectomy. Expression of collagen and profibrotic genes in aortic VSMCs increased in mice after 5/6 subtotal nephrectomy and in mice producing human angiopoietin-2. Angiopoietin-2 stimulated endothelial expression of chemokines and adhesion molecules for monocytes, increased Ly6C(low) macrophages in aorta, and increased the expression of the profibrotic cytokine TGF-?1 in aortic endothelial cells and Ly6C(low) macrophages. Angiopoietin-2 blockade attenuated expression of monocyte chemokines, profibrotic cytokines, and collagen in aorta of mice after 5/6 subtotal nephrectomy. This study identifies angiopoietin-2 as a link between kidney fibrosis and arterial stiffness. Targeting angiopoietin-2 to attenuate inflammation and collagen expression may provide a novel therapy for cardiovascular disease in CKD.
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Risk factors of sensitization to human leukocyte antigen in end-stage renal disease patients.
Hum. Immunol.
PUBLISHED: 02-04-2014
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Pre-sensitization to human leukocyte antigen (HLA) is closely related to the prognosis of renal transplantation. Concerning the risk factors for HLA sensitization, most studies focused only on selected transplant candidates.
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Fatostatin displays high antitumor activity in prostate cancer by blocking SREBP-regulated metabolic pathways and androgen receptor signaling.
Mol. Cancer Ther.
PUBLISHED: 02-03-2014
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Current research links aberrant lipogenesis and cholesterogenesis with prostate cancer development and progression. Sterol regulatory element-binding proteins (SREBP; SREBP-1 and SREBP-2) are key transcription factors controlling lipogenesis and cholesterogenesis via the regulation of genes related to fatty acid and cholesterol biosynthesis. Overexpression of SREBPs has been reported to be significantly associated with aggressive pathologic features in human prostate cancer. Our previous results showed that SREBP-1 promoted prostate cancer growth and castration resistance through induction of lipogenesis and androgen receptor (AR) activity. In the present study, we evaluated the anti-prostate tumor activity of a novel SREBP inhibitor, fatostatin. We found that fatostatin suppressed cell proliferation and anchorage-independent colony formation in both androgen-responsive LNCaP and androgen-insensitive C4-2B prostate cancer cells. Fatostatin also reduced in vitro invasion and migration in both the cell lines. Further, fatostatin caused G2-M cell-cycle arrest and induced apoptosis by increasing caspase-3/7 activity and the cleavages of caspase-3 and PARP. The in vivo animal results demonstrated that fatostatin significantly inhibited subcutaneous C4-2B tumor growth and markedly decreased serum prostate-specific antigen (PSA) level compared with the control group. The in vitro and in vivo effects of fatostatin treatment were due to blockade of SREBP-regulated metabolic pathways and the AR signaling network. Our findings identify SREBP inhibition as a potential new therapeutic approach for the treatment of prostate cancer.
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Removal processes of disinfection byproducts in subsurface-flow constructed wetlands treating secondary effluent.
Water Res.
PUBLISHED: 01-21-2014
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The removal efficiencies and the kinetics of disinfection byproducts (DBPs) were studied in six greenhouse laboratory-scale SSF CWs. Cattail (Typha latifolia) and its litter (collected from the aboveground samples of cattail in autumn) were used as a potential phytoremediation technology and as a primary substrate, respectively, for DBP removal. Results showed that most of the 11 DBPs (except chloroform and 1, 1-dichloropropanone) were efficiently removed (>90%) in six SSF CWs with hydraulic retention time of 5 d and there were no significant differences among the systems. Under the batch mode, the removal of DBPs in SSF CWs followed first-order kinetics with half-lives of 1.0-770.2 h. As a primary DBP in wastewater effluent, removal efficiencies for chloroform were higher in planted systems than in unplanted ones and plant uptake accounted for more than 23.8% of the removal. Plant litter greatly enhanced the removal of trihalomethanes (THMs) by supplying primary substrates and reducing conditions, and the formation of dichloromethane supported the anaerobic biodegradation of THMs via reductive dechlorination in SSF CWs. Trichloroacetonitrile was completely removed within 10 h in each system and hydrolysis was considered to be the dominant process as there was a rapid formation of the hydrolysis byproduct, trichloroacetamide.
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Ultrafast coating procedure for graphene on solid-phase microextraction fibers.
Talanta
PUBLISHED: 01-10-2014
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Graphene's unsurpassed specific surface area (up to 2630 m(2)/g) makes it be an ideal absorbent. To promote its use as a sorption coating in solid phase microextraction, an ultrafast method was established, able to coat a stable layer of graphene on a metal fiber in only 23s, with adjustable coating thickness between 10 and 40 µm by using sleeve barrels. The core idea includes: (1) use of semi-polymerized dimethylsiloxane as a sticky pre-liner to glue graphene and (2) rapid conversion from pre-liner to elastic polydimethylsiloxane (PDMS) to fix the glued graphene. Ultrafast conversion of the pre-liner to PDMS was achieved by direct heating of the metallic fibers. The method produced very stable and durable fibers, capable of being used for at least 120 extractions-desorption cycles and stored at room temperature for at least 20 months. Interestingly, the new method could always coat a layer of mossy graphene on the fibers to largely increase their extraction capacity. Their limit of detection reached 2 pg/L PAHs, being about 3 orders of magnitude better than that of the reported graphene-based fibers. They were applicable to the direct extraction of trace PAHs in beverages, with a linear regression range from 10 to 1000 pg/L, and recoveries of 88.9-105.3%. The relative standard deviations of peak area were 2.9-8.9% for the same fiber and 3.0-10.0% for different fibers. The method is also suitable for re-coating a used fiber and extendable to fast coating other solid sorbents on heat-resistant supports.
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Haemolytic uremic syndrome following fire ant bites.
BMC Nephrol
PUBLISHED: 01-06-2014
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Haemolytic-uremic syndrome (HUS) is a severe, life-threatening disease with symptoms such as haemolytic anaemia, renal failure, and a low platelet count. Possible aetiology includes bacterial infections, medication, post-hematopoietic cell transplantation, pregnancy, autoimmune disease, and acquired immunodeficiency syndrome.
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MDM4 Overexpressed in Acute Myeloid Leukemia Patients with Complex Karyotype and Wild-Type TP53.
PLoS ONE
PUBLISHED: 01-01-2014
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Acute myeloid leukemia patients with complex karyotype (CK-AML) account for approximately 10-15% of adult AML cases, and are often associated with a poor prognosis. Except for about 70% of CK-AML patients with biallelic inactivation of TP53, the leukemogenic mechanism in the nearly 30% of CK-AML patients with wild-type TP53 has remained elusive. In this study, 15 cases with complex karyotype and wild-type TP53 were screened out of 140 de novo AML patients and the expression levels of MDM4, a main negative regulator of p53-signaling pathway, were detected. We ruled out mutations in genes associated with a poor prognosis of CK-AML, including RUNX1 or FLT3-ITD. The mRNA expression levels of the full-length of MDM4 (MDM4FL) and short isoform MDM4 (MDM4S) were elevated in CK-AML relative to normal karyotype AML (NK-AML) patients. We also explored the impact of MDM4 overexpression on the cell cycle, cell proliferation and the spindle checkpoint of HepG2 cells, which is a human cancer cell line with normal MDM4 and TP53 expression. The mitotic index and the expression of p21, BubR1 and Securin were all reduced following Nocodazole treatment. Moreover, karyotype analysis showed that MDM4 overexpression might lead to aneuploidy or polyploidy. These results suggest that MDM4 overexpression is related to CK-AML with wild-type TP53 and might play a pathogenic role by inhibiting p53-signal pathway.
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The Endogenous Nitric Oxide Mediates Selenium-Induced Phytotoxicity by Promoting ROS Generation in Brassica rapa.
PLoS ONE
PUBLISHED: 01-01-2014
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Selenium (Se) is suggested as an emerging pollutant in agricultural environment because of the increasing anthropogenic release of Se, which in turn results in phytotoxicity. The most common consequence of Se-induced toxicity in plants is oxidative injury, but how Se induces reactive oxygen species (ROS) burst remains unclear. In this work, histofluorescent staining was applied to monitor the dynamics of ROS and nitric oxide (NO) in the root of Brassica rapa under Se(IV) stress. Se(IV)-induced faster accumulation of NO than ROS. Both NO and ROS accumulation were positively correlated with Se(IV)-induced inhibition of root growth. The NO accumulation was nitrate reductase (NR)- and nitric oxide synthase (NOS)-dependent while ROS accumulation was NADPH oxidase-dependent. The removal of NO by NR inhibitor, NOS inhibitor, and NO scavenger could alleviate Se(IV)-induced expression of Br_Rbohs coding for NADPH oxidase and the following ROS accumulation in roots, which further resulted in the amelioration of Se(IV)-induced oxidative injury and growth inhibition. Thus, we proposed that the endogenous NO played a toxic role in B. rapa under Se(IV) stress by triggering ROS burst. Such findings can be used to evaluate the toxic effects of Se contamination on crop plants.
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Selenium Inhibits Root Elongation by Repressing the Generation of Endogenous Hydrogen Sulfide in Brassica rapa.
PLoS ONE
PUBLISHED: 01-01-2014
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Selenium (Se) has been becoming an emerging pollutant causing severe phytotoxicity, which the biochemical mechanism is rarely known. Although hydrogen sulfide (H2S) has been suggested as an important exogenous regulator modulating plant physiological adaptions in response to heavy metal stress, whether and how the endogenous H2S regulates Se-induce phytotoxicity remains unclear. In this work, a self-developed specific fluorescent probe (WSP-1) was applied to track endogenous H2S in situ in the roots of Brassica rapa under Se(IV) stress. Se(IV)-induced root growth stunt was closely correlated with the inhibition of endogenous H2S generation in root tips. Se(IV) stress dampened the expression of most LCD and DCD homologues in the roots of B. rapa. By using various specific fluorescent probes for bio-imaging root tips in situ, we found that the increase in endogenous H2S by the application of H2S donor NaHS could significantly alleviate Se(IV)-induced reactive oxygen species (ROS) over-accumulation, oxidative impairment, and cell death in root tips, which further resulted in the recovery of root growth under Se(IV) stress. However, dampening the endogenous H2S could block the alleviated effect of NaHS on Se(IV)-induced phytotoxicity. Finally, the increase in endogenous H2S resulted in the enhancement of glutathione (GSH) in Se(IV)-treated roots, which may share the similar molecular mechanism for the dominant role of H2S in removing ROS by activating GSH biosynthesis in mammals. Altogether, these data provide the first direct evidences confirming the pivotal role of endogenous H2S in modulating Se(IV)-induced phytotoxicity in roots.
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An evaluation of alternative methods for constructing phylogenies from whole genome sequence data: a case study with Salmonella.
PeerJ
PUBLISHED: 01-01-2014
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Comparative genomics based on whole genome sequencing (WGS) is increasingly being applied to investigate questions within evolutionary and molecular biology, as well as questions concerning public health (e.g., pathogen outbreaks). Given the impact that conclusions derived from such analyses may have, we have evaluated the robustness of clustering individuals based on WGS data to three key factors: (1) next-generation sequencing (NGS) platform (HiSeq, MiSeq, IonTorrent, 454, and SOLiD), (2) algorithms used to construct a SNP (single nucleotide polymorphism) matrix (reference-based and reference-free), and (3) phylogenetic inference method (FastTreeMP, GARLI, and RAxML). We carried out these analyses on 194 whole genome sequences representing 107 unique Salmonella enterica subsp. enterica ser. Montevideo strains. Reference-based approaches for identifying SNPs produced trees that were significantly more similar to one another than those produced under the reference-free approach. Topologies inferred using a core matrix (i.e., no missing data) were significantly more discordant than those inferred using a non-core matrix that allows for some missing data. However, allowing for too much missing data likely results in a high false discovery rate of SNPs. When analyzing the same SNP matrix, we observed that the more thorough inference methods implemented in GARLI and RAxML produced more similar topologies than FastTreeMP. Our results also confirm that reproducibility varies among NGS platforms where the MiSeq had the lowest number of pairwise differences among replicate runs. Our investigation into the robustness of clustering patterns illustrates the importance of carefully considering how data from different platforms are combined and analyzed. We found clear differences in the topologies inferred, and certain methods performed significantly better than others for discriminating between the highly clonal organisms investigated here. The methods supported by our results represent a preliminary set of guidelines and a step towards developing validated standards for clustering based on whole genome sequence data.
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Tacrolimus-based versus cyclosporine-based immunosuppression in hepatitis C virus-infected patients after liver transplantation: a meta-analysis and systematic review.
PLoS ONE
PUBLISHED: 01-01-2014
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Most liver transplant recipients receive calcineurin inhibitors (CNIs), especially tacrolimus and cyclosporine, as immunosuppressant agents to prevent rejection. A controversy exists as to whether the outcomes of hepatitis C virus (HCV)-infected liver transplant patients differ based on the CNIs used. This meta-analysis compares the clinical outcomes of tacrolimus-based and cyclosporine-based immunosuppression, especially cases of HCV recurrence in liver transplant patients with end-stage liver disease caused by HCV infection.
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Glycemic control and radiographic manifestations of tuberculosis in diabetic patients.
PLoS ONE
PUBLISHED: 01-01-2014
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Radiographic manifestations of pulmonary tuberculosis (TB) in patients with diabetes mellitus (DM) have previously been reported, with inconsistent results. We conducted a study to investigate whether glycemic control has an impact on radiographic manifestations of pulmonary TB.
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[Effects of biochar application on greenhouse gas emission from paddy soil and its physical and chemical properties].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 12-31-2013
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A field experiment was conducted to investigate the effects of rice straw returning and rice straw biochar and life rubbish biochar application on the greenhouse gas (CH4, CO2 and N2O) emission from paddy soil, its physical and chemical properties, and rice grain yield. Compared with rice straw returning, applying rice straw biochar decreased the cumulative CH4 and N2O emissions from paddy soil significantly by 64.2% - 78.5% and 16.3% - 18.4%, respectively. Whether planting rice or not, the cumulative N2O emission from paddy soil under the applications of rice straw biochar and life rubbish biochar was decreased significantly, compared with that without biochar amendment. Under the condition of no rice planting, applying life rubbish biochar reduced the cumulative CO2 emission significantly by 25.3%. Rice straw biochar was superior to life rubbish biochar in improving soil pH and available potassium content. Both rice straw biochar and life rubbish biochar could increase the soil organic carbon content significantly, but had less effects on the soil bulk density, total nitrogen and available phosphorus contents, cation exchange capacity (CEC), and grain yield. It was suggested that compared with rice straw returning, straw biochar was more effective in improving rice grain yield.
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[Rhodamine-triazine fluorescence probe recognition for Al3+ and Cr3+].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 12-28-2013
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A symmetrical rhodamine-triazine derivative was synthesized through step-by-step substitution of rhodamine B ethylenediamine with two chlorines on cyanuric chloride. It showed an extreme selectivity for Al3+ and Cr3+ over other common metal ions and strong fluorescence emission and UV-Visible absorption in the ethanol solution of pH 4. Due to the difference in complexing ability, the recognition of the derivative for Al3+ and Cr3+ was not interfered by other coexisting ions. Under certain conditions, the derivative can be used as high selectivity and high sensitivity Al3+ or Cr3+ fluorescence and colorimetric enhanced probe.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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