JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Synthesis of Semiconducting Polymer Microparticles as Solid Ionophore with Abundant Complexing Sites for Long-life Pb(II) Sensors.
ACS Appl Mater Interfaces
PUBLISHED: 11-19-2014
Show Abstract
Hide Abstract
Intrinsically electrically semiconducting microparticles of semi-ladder poly(m-phenylenediamine-co-2-hydroxy-5-sulfonic aniline) structure containing abundant functional groups like -NH-, -N=, -NH2, -OH, -SO3H as complexation sites, were efficiently synthesized by chemical oxidative copolymerization of m-phenylenediamine and 2-hydroxy-5-sulfonic aniline. The obtained copolymers were found to be non-porous spherical microparticles that were able to achieve greater ?-conjugated structure, smaller particle aggregate size, and stronger interaction with Pb(II) ions than poly(m-phenylenediamine) containing only -NH-, -N=, and -NH2. A potentiometric Pb(II) sensor was fabricated based on the copolymer microparticles as a crucial solid ionophore component within plasticized PVC. The sensor exhibited a Nernstian response to Pb(II) ions over a wide concentration range, together with a fast response, a wide pH range capability, a long lifetime of up to 5 months, and good selectivity over a wide variety of other ions and redox species. The process for synthesizing the microparticles and fabricating the Pb(II)-sensor can be facilely scaled-up for use in the straightforward long-term on-line monitoring of Pb(II) ions in heavily polluted wastewaters. This study develops an understanding of the facile synthesis of conducting microparticles bearing many functional groups and their structures governing the potentiometric susceptibility towards interaction between Pb(II) ions and the microparticles for fabricating robust long-lived Pb(II)-sensor, signifying the potential suitability of such novel materials for inexpensive sensitive detection of Pb(II) ions.
Related JoVE Video
Differential effects of tumor necrosis factor-? on matrix metalloproteinase-2 expression in human myometrial and uterine leiomyoma smooth muscle cells.
Hum. Reprod.
PUBLISHED: 11-16-2014
Show Abstract
Hide Abstract
Does tumor necrosis factor-? (TNF-?) differentially regulate matrix metalloproteinase-2 (MMP-2) expression in leiomyomas compared with normal myometrium?
Related JoVE Video
Uptake of Epoxydiol Isomers Accounts for Half of the Particle-Phase Material Produced from Isoprene Photooxidation via the HO2 pathway.
Environ. Sci. Technol.
PUBLISHED: 11-07-2014
Show Abstract
Hide Abstract
The oxidation of isoprene is a globally significant source of secondary organic material (SOM). The relative importance of different parallel pathways, however, remains inadequately understood and quantified. SOM production from isoprene photooxidation was studied under hydroperoxyl-dominant conditions for <5% relative humidity and at 20 °C in the presence of highly acidic to completely neutralized sulfate particles. Isoprene photooxidation was separated from SOM production by using two continuously mixed flow reactors connected in series and operated at steady state. Two on-line mass spectrometers separately sampled the gas and particle phases in the reactor outflow. The loss of specific gas-phase species as contributors to the production of SOM was thereby quantified. The produced SOM mass concentration was directly proportional to the loss of isoprene epoxydiol (IEPOX) isomers from the gas phase. IEPOX isomers lost from the gas phase accounted for (46 ± 11)% of the produced SOM mass concentration. The IEPOX isomers comprised (59 ± 21)% (molecular count) of the loss of monitored gas-phase species. The implication is that for the investigated reaction conditions the SOM production pathways tied to IEPOX isomers accounted for half of the SOM mass concentration.
Related JoVE Video
Acclimation to very-low CO2: Contribution of LCIB and LCIA to inorganic carbon uptake in Chlamydomonas reinhardtii.
Plant Physiol.
PUBLISHED: 10-23-2014
Show Abstract
Hide Abstract
The limiting-CO2 inducible CO2 concentrating mechanism (CCM) of microalgae represents an effective strategy to capture CO2 when its availability is limited. At least two limiting-CO2 acclimation states, termed low CO2 and very-low CO2, have been demonstrated in the model microalga Chlamydomonas reinhardtii, and many questions still remain unanswered regarding both the regulation of these acclimation states and the molecular mechanism underlying operation of the CCM in these two states. This study examines the role of two proteins, LCIA (also named NAR1.2) and LCIB, in the CCM of C. reinhardtii. The identification of an LCIA-LCIB double mutant based on its inability to survive in very-low CO2 suggests that both LCIA and LCIB are critical for survival in very-low CO2. The contrasting impacts of individual mutations in LCIB and LCIA in comparison with the impacts of LCIB-LCIA double mutations on growth and Ci-dependent photosynthetic O2 evolution reveal distinct roles of LCIA and LCIB in the CCM. While both LCIA and LCIB are essential for very-low CO2 acclimation, LCIB appears to function in a CO2 uptake system, while LCIA appears to be associated with a HCO3- transport system. The contrasting and complementary roles of LCIA and LCIB in acclimation to low CO2 and very-low CO2 suggest a possible mechanism of differential regulation of the CCM based on the inhibition of HCO3- transporters by moderate to high levels of CO2.
Related JoVE Video
Directing the fate of human and mouse mesenchymal stem cells by hydroxyl-methyl mixed self-assembled monolayers with varying wettability.
J Mater Chem B Mater Biol Med
PUBLISHED: 10-21-2014
Show Abstract
Hide Abstract
Self-assembled monolayers (SAMs) of alkanethiols on gold have been employed as model substrates to investigate the effects of surface chemistry on cell behavior. However, few studies were dedicated to the substrates with a controlled wettability in studying stem cell fate. Here, mixed hydroxyl (-OH) and methyl (-CH3) terminated SAMs were prepared to form substrates with varying wettability, which were used to study the effects of wettability on the adhesion, spreading, proliferation and osteogenic differentiation of mesenchymal stem cells (MSCs) from human and mouse origins. The numbers of adhered human fetal MSCs (hMSCs) and mouse bone marrow MSCs (mMSCs) were maximized on -OH/-CH3 mixed SAMs with a water contact angle of 40~70° and 70~90°, respectively. Hydrophilic mixed SAMs with a water contact angle of 20~70° also promoted the spreading of both hMSCs and mMSCs. Both hMSCs and mMSCs proliferation was most favored on hydrophilic SAMs with a water contact angle around 70°. In addition, a moderate hydrophilic surface (with a contact angle of 40~90° for hMSCs and 70° for mMSCs) promoted osteogenic differentiation in the presence of biological stimuli. Hydrophilic mixed SAMs with a moderate wettability tended to promote the expression of ?v?1 integrin of MSCs, indicating that the tunable wettability of the mixed SAMs may guide osteogenesis through mediating the ?v?1 integrin signaling pathway. Our work can direct the design of biomaterials with controllable wettability to promote the adhesion, proliferation and differentiation of MSCs from different sources.
Related JoVE Video
Negative association of donor age with CD34(+) cell dose in mixture allografts of G-CSF-primed bone marrow and G-CSF-mobilized peripheral blood harvests.
Chin. Med. J.
PUBLISHED: 10-16-2014
Show Abstract
Hide Abstract
The effects of donor characteristics on CD34(+) cell dose remain controversial. Recently, we developed a novel haploidentical transplant protocol, in which mixture allografts of granulocyte colony-stimulating factor (G-CSF)-primed bone marrow (G-BM) and G-CSF-mobilized peripheral blood (G-PB) were used. The aim of this study was to investigate the effects of donor characteristics on CD34(+) cell dose in mixture allografts of G-BM and G-PB.
Related JoVE Video
Fabrication and characterization of chitosan-collagen crosslinked membranes for corneal tissue engineering.
J Biomater Sci Polym Ed
PUBLISHED: 10-09-2014
Show Abstract
Hide Abstract
This article describes a chitosan-collagen composite membrane as corneal tissue-engineering biomaterials. The membrane was prepared by dissolving the chitosan into collagen with the weight ratio of 0, 15, 30, 45, 60, and 100%, followed by crosslinked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. Mechanical properties, contact angles, and optical transmittance were determined and compared between chitosan membrane and crosslinking composite membrane. As a result, the optical transparency and mechanical strength of the chitosan-collagen membranes were significantly better than that of the sample of chitosan. In addition, in vitro cell culture studies revealed that the collagen has no negative effect on the cell morphology, viability, and proliferation and possess good biocompatibility. Overall, the dendrimer crosslinked chitosan-collagen composite membranes showed promising properties that suggest that these might be suitable biomaterials for corneal tissue-engineering applications.
Related JoVE Video
Surface structures of poly(methyl methacrylate) films influenced by chain entanglement in the corresponding film-formation solution.
Soft Matter
PUBLISHED: 10-09-2014
Show Abstract
Hide Abstract
The effects of the properties of casting solution on the surface structure of poly(methyl methacrylate) (PMMA) films were systematically investigated. It was observed that the hydrophobicity of PMMA films increased with increasing viscosity of the corresponding polymer solution regardless of the film-formation techniques that were utilized. The ratio of the C-H symmetric stretching vibrations of methylene groups (hydrophobic components, with a peak at 2910 cm(-1)) to those of the ester methyl groups (relative hydrophilic components, with a peak at 2955 cm(-1)) from sum frequency generation (SFG) vibrational spectra, A2910/A2955, was used as a parameter to evaluate the structure on the film surface, which was related to the surface wettability of the films. The results showed that A2910/A2955 of cast PMMA films increased linearly with ?sp(0.3) (?sp, the specific viscosity of the casting solution), whereas that of the corresponding spin-coated films showed a linear relationship defined as ?sp(0.3)E(0.26), where E is the average number of entanglement points per molecule (E = Mw/Me). These results indicate that a relative equilibrium conformation on the PMMA film surface, adopted from the perspective of thermodynamics, was easily achieved during film formation, when the conformation of the polymer chains in the corresponding casting solution was close to that in the bulk. For the spin-coated films, the chain entanglement structure in the casting solution was a more important factor for the resulting film to reach a relative equilibrium state, since this structure was in favor of maintaining the pristine conformation in casting solution under centrifugal force during spin-coating. This work may help to enhance the fundamental understanding of the formation of the film surface structure from polymer solution to the resulting solid film, which will affect not only the corresponding surface properties, but also the dynamics of the resulting thin films.
Related JoVE Video
A Novel Pseudomonas aeruginosa Strain with an oprD Mutation in Relation to a Nosocomial Respiratory Infection Outbreak in an Intensive Care Unit.
J. Clin. Microbiol.
PUBLISHED: 10-08-2014
Show Abstract
Hide Abstract
Seven imipenem-resistant Pseudomonas aeruginosa isolates were recovered from the sputum samples of pneumonia patients in southwestern China. They had identical antibiotic resistance patterns and indistinguishable pulsed-field gel electrophoresis profiles. Nucleotide sequence analysis revealed a 4-bp (AGTC) insertion in the oprD gene, resulting in a frameshift in the cognate open reading frame. These isolates became imipenem susceptible when the chromosomal oprD lesion was complemented, indicating that the 4-bp insertion in the oprD gene resulted in imipenem resistance.
Related JoVE Video
Rationale for co-targeting IGF-1R and ALK in ALK fusion-positive lung cancer.
Nat. Med.
PUBLISHED: 08-31-2014
Show Abstract
Hide Abstract
Crizotinib, a selective tyrosine kinase inhibitor (TKI), shows marked activity in patients whose lung cancers harbor fusions in the gene encoding anaplastic lymphoma receptor tyrosine kinase (ALK), but its efficacy is limited by variable primary responses and acquired resistance. In work arising from the clinical observation of a patient with ALK fusion-positive lung cancer who had an exceptional response to an insulin-like growth factor 1 receptor (IGF-1R)-specific antibody, we define a therapeutic synergism between ALK and IGF-1R inhibitors. Similar to IGF-1R, ALK fusion proteins bind to the adaptor insulin receptor substrate 1 (IRS-1), and IRS-1 knockdown enhances the antitumor effects of ALK inhibitors. In models of ALK TKI resistance, the IGF-1R pathway is activated, and combined ALK and IGF-1R inhibition improves therapeutic efficacy. Consistent with this finding, the levels of IGF-1R and IRS-1 are increased in biopsy samples from patients progressing on crizotinib monotherapy. Collectively these data support a role for the IGF-1R-IRS-1 pathway in both ALK TKI-sensitive and ALK TKI-resistant states and provide a biological rationale for further clinical development of dual ALK and IGF-1R inhibitors.
Related JoVE Video
Alcohol drinking and the risk of colorectal cancer death: a meta-analysis.
Eur. J. Cancer Prev.
PUBLISHED: 08-30-2014
Show Abstract
Hide Abstract
A causal link between alcohol consumption and colorectal cancer (CRC) was established only recently by the International Agency for Research on Cancer. However, the quantitative association between alcohol drinking and CRC mortality is still an open question. We performed a systemic review and meta-analysis on epidemiological studies to quantify the risk for CRC mortality at different levels of alcohol consumption. A literature search was carried out in PubMed and Web of Science to identify all relevant studies published from January 1966 to June 2013. The pooled relative risk (RR) and the corresponding 95% confidence interval (CI) were estimated by categorical meta-analysis. A dose-risk relation was also analyzed. Nine cohort studies exploring the association between CRC mortality and alcohol drinking were identified. Compared with non/occasional drinkers, the pooled RR was 1.03 (95% CI, 0.93-1.15) for any, 0.97 (95% CI, 0.86-1.10) for light (?12.5?g/day of ethanol), 1.04 (95% CI, 0.94-1.16) for moderate (12.6-49.9?g/day of ethanol), and 1.21 (1.01-1.46) for heavy drinkers (?50?g/day of ethanol). For heavy drinkers, the pooled estimate was apparently higher for men (RR=1.28; 95% CI, 1.13-1.46) than for women (RR=0.79; 95% CI, 0.40-1.54; P(heterogeneity)=0.007). The dose-response analysis showed a J-shaped relationship between alcohol consumption and CRC mortality. The present meta-analysis provides the evidence for an association between heavy alcohol drinking (?50?g/day of ethanol) and CRC mortality.
Related JoVE Video
Late-stage diversification of peptides by metal-free C-H arylation.
Chemistry
PUBLISHED: 08-28-2014
Show Abstract
Hide Abstract
The bioorthogonal late-stage diversification of functionalized oligopeptides was accomplished through a metal-free, site-selective C-H arylation of engineered indole derivatives under mild reaction conditions.
Related JoVE Video
Identification and quantification of shipping emissions in Bohai Rim, China.
Sci. Total Environ.
PUBLISHED: 08-25-2014
Show Abstract
Hide Abstract
Rapid development of port and shipbuilding industry in China has badly affected the ambient air quality of coastal zone due to shipping emissions. A total of 60 ambient air samples were collected from background site of Tuoji Island in Bohai Sea strait. The air samples were analyzed for PM2.5, organic carbon (OC), element carbon (EC), inorganic elements, and water-soluble ions. The maximum concentration of PM2.5 was observed during spring (73.6 ?g·m(-3)) compared to winter (39.0 ?g·m(-3)) with mean of 54.6 ?g·m(-3). Back trajectory air mass analysis together with temporal distribution of vanadium (V) showed that V could be the typical tracer of shipping emissions at Tuoji Island. Furthermore, the ratios of vanadium to nickel (V/Ni), vanadium to lead (V/Pb) and vanadium to zinc (V/Zn) also suggest shipping emissions at Tuoji Island. The annual average primary PM2.5 estimate of shipping emissions was 0.65 ?g·m(-3) at Tuoji Island, accounting for 2.94% of the total primary PM2.5, with a maximum of 3.16% in summer and a minimum of 2.39% in autumn.
Related JoVE Video
Effects of lead exposure on d-serine metabolism in the hippocampus of mice at the early developmental stages.
Toxicology
PUBLISHED: 08-12-2014
Show Abstract
Hide Abstract
The aim of this study was to explore the mechanisms of lead neurotoxicity by focusing on the alteration of d-serine metabolism in the hippocampus of mice at the early life. Mother mice and their offspring were exposed to 0, 0.5, 1.0 and 2.0g/L lead in lead acetate via drinking water from the first day of gestation until the postnatal day (PND) 40. Morris water maze was used to measure the spatial learning and memory ability of PND 40 mice. Expressions of serine racemase (SR), d-amino acid oxidase (DAAO), alanine-serine- cysteine transporter-1 (asc-1) and subunits of N-methyl-d-aspartate receptor (NMDAR) in the hippocampus of PND 10, 20 and 40 mice were examined by western blot and real time RT-PCR. Findings from this study disclosed that the spatial learning ability of mice tested by place trial could be significantly impaired by 0.5g/L lead exposure, and the spatial memory ability tested by probe trail could be impaired by 1.0g/L lead exposure. Exposure to 2.0g/L lead in the water could significantly inhibit the protein and mRNA expression of SR; conversely enhance the expression of DAAO protein and mRNA in the hippocampus during the early developmental stages. However, the protein expressions of DAAO and asc-1 in the hippocampus were significantly enhanced by 0.5g/L lead exposure at different developmental stages. On the other hand, the protein and mRNA expressions of both NR1 and NR2A were inhibited significantly by 1.0g/L lead exposure since PND 10, and by 0.5g/L lead exposure since PND 20. Noteworthy, the protein expression of NR2B was inhibited significantly by 0.5g/L lead exposure in PND 10 mice, and by 1.0g/L lead exposure in PND 20 mice, but there was no significant group difference in PND 40 mice. Meanwhile, expressions of asc-1 and NR2B mRNA were not affected obviously by lead exposure. In conclusion, chronic lead exposure during brain development might affect d-serine metabolism by enhancing its degradation, which might be related to the inhibited expression of NMDAR subunits, and furthermore contribute to deficits in learning and memory ability in mice.
Related JoVE Video
Synthesis and biological evaluation of novel thiadiazole amides as potent Cdc25B and PTP1B inhibitors.
Bioorg. Med. Chem. Lett.
PUBLISHED: 07-30-2014
Show Abstract
Hide Abstract
A series of novel thiadiazole amide derivatives have been synthesized and evaluated for inhibitory activities against Cdc25B and PTP1B. Most of them showed inhibitory activities against Cdc25B (IC50=1.18-8.01 ?g/mL) and PTP1B (IC50=0.85-8.75 ?g/mL), respectively. Moreover, compounds 5b and 4l were most potent with IC50 values of 1.18 and 0.85 ?g/mL for Cdc25B and PTP1B, respectively, compared with reference drugs Na3VO4 (IC50=0.93 ?g/mL) and oleanolic acid (IC50=0.85 ?g/mL). The results of selectivity experiments showed that the target compounds were selective inhibitors against PTP1B and Cdc25B. Enzyme kinetic experiments demonstrated that compound 5k was a specific inhibitor with the typical characteristics of a mixed inhibitor.
Related JoVE Video
Impact of preoperative anemia on relapse and survival in breast cancer patients.
BMC Cancer
PUBLISHED: 07-09-2014
Show Abstract
Hide Abstract
Previous studies have shown that preoperative anemia is correlated with the prognoses of various solid tumors. This study was performed to determine the effect of preoperative anemia on relapse and survival in patients with breast cancer.
Related JoVE Video
Reconstruction of cervical scar contracture using axial thoracic flap based on the thoracic branch of the supraclavicular artery.
Ann Plast Surg
PUBLISHED: 07-09-2014
Show Abstract
Hide Abstract
Cervical scar contracture causes both physical and psychological distress for burn patients. Many pedicle flaps or skin grafting have been suggested for reconstruction of cervical scar contracture with variable results in the literature. The authors present the axial thoracic flap based on the thoracic branch of the supraclavicular artery (TBSA) for reconstruction of cervical scar contracture.
Related JoVE Video
Integrin ?v?3 mediates the synergetic regulation of core-binding factor ?1 transcriptional activity by gravity and insulin-like growth factor-1 through phosphoinositide 3-kinase signaling.
Bone
PUBLISHED: 07-04-2014
Show Abstract
Hide Abstract
Mechanical stimulation and biological factors coordinately regulate bone development and regeneration; however, the underlying mechanisms are poorly understood. Microgravity induces bone loss, which may be partly related to the development of resistance to local cytokines, including insulin-like growth factor 1 (IGF-1). Here, we report the involvement of integrin ?v?3 in microgravity-associated bone loss. An established OSE-3T3 cell model was stably transfected with a 6OSE2 (Osteoblast-Specific Element 2)-luciferase reporter and cultured under simulated microgravity (SMG) and hypergravity (HG) conditions in the presence or absence of IGF-1, the disintegrin echistatin, the phosphoinositide 3-kinase (PI3K) inhibitor LY294002, or combinations of these agents. Activity of core-binding factor ?1 (Cbfa1), an essential transcription factor for osteoblastic differentiation and osteogenesis, was reflected by luciferase activity. Different gravity conditions affected the induction of IGF-1 and subsequent effects on Cbfa1 transcription activity. SMG and HG influenced the expression and activity of integrin ?v?3 and phosphorylation level of p85. LY294002 inhibited the effects of HG or IGF-1 on Cbfa1 activity, indicating that HG and IGF-1 could increase Cbfa1 activity via PI3K signaling. Inhibition of integrin ?v?3 by echistatin attenuated the induction of IGF-1 and thus its effect on Cbfa1 activity under normal and HG conditions. Co-immunoprecipitation demonstrated that integrin ?3 interacted with insulin receptor substrate 1, and that this interaction was decreased under SMG and increased under HG conditions. These results suggest that integrin ?v?3 mediates the synergetic regulation of Cbfa1 transcription activity by gravity and IGF-1 via PI3K signaling.
Related JoVE Video
Neuroprotective agents target molecular mechanisms of disease in ALS.
Drug Discov. Today
PUBLISHED: 06-09-2014
Show Abstract
Hide Abstract
Amyotrophic lateral sclerosis (ALS) is a debilitating disease characterized by progressive loss of voluntary motor neurons leading to muscle atrophy, weight loss and respiratory failure. Evidence suggests that inflammation, oxidative stress, mitochondrial dysfunction, apoptosis, glutamate excitotoxicity and proteasomal dysfunction are all responsible for ALS pathogenesis. We review neuroprotective agents with the ability to reduce ALS-related bodyweight loss, summarize the various therapies tested on animal models targeting the proposed molecular mechanisms, compare their effects on bodyweight loss, muscle damage, disease onset, duration and survival, and analyze their structure-activity relationships, with the overall goal of creating a screening strategy for further clinical application.
Related JoVE Video
Subcellular distribution of Cd and Zn and MT mRNA expression in the hepatopancreas of Sinopotamon henanense after single and co-exposure to Cd and Zn.
Comp. Biochem. Physiol. C Toxicol. Pharmacol.
PUBLISHED: 05-26-2014
Show Abstract
Hide Abstract
The freshwater crab Sinopotamon henanense was exposed to Cd (50, 100 and 500?gl(-1)) and Zn (100 and 1000?gl(-1)) either on their own or in combination. At 14 and 28days the hepatopancreas were taken and total metal and metallothionein (MT) in transcript abundance were assessed. In addition, following homogenization of the hepatopancreas differential centrifugation, NaOH digestion and heat denaturation steps were carried out to identify subcellular compartmentalization, defined as metal-sensitive fraction [MSF-organelles and heat-denaturable proteins (HDP)] and biologically detoxified metals [BDM-heat-stable proteins (HSP) and metal-rich granules (MRG)]. The results showed that concentration of the non-essential metal Cd was more responsive to waterborne metal exposures than the concentration of essential metal Zn; the latter metal was better regulated and exhibited only 2-3 fold increases relative to the control. Of the six fractions, the HSP fraction was the predominant metal-binding compartment for Cd. The proportion and accumulation of Cd in this fraction increased with the single Cd exposures, which suggest that metallothionein-like proteins play a key role in metal detoxification in the hepatopancreas of S. henanense. It was surprising that more Zn was in the HSP fraction than Cd, but its contribution did not increase progressively with the single Zn exposures. Despite the increases in Cd in the HSP fraction during single Cd exposures, some accumulation of Cd was observed in putative MSF (e.g., mitochondria), which showed that metal detoxification was incomplete. The results demonstrated that the Cd content decreased in metal mixture groups especially when mixed with higher Zn, while the Cd accumulation in MSF was also reduced when Zn was added, which suggested that Zn might alleviate the toxic effects of Cd through changing the subcellular distribution of Cd. MT mRNA expression was also determined in our report, the results showed that both Cd and Zn had the ability of inducing MT mRNA expression. Additionally, the MT mRNA transcription level was enhanced when Cd was mixed with Zn. We suggest, therefore, that MT synthesis following increased MT mRNA expression is one of the mechanisms in which Zn reduced the bioaccumulation of Cd.
Related JoVE Video
Childhood experiences of parental rearing patterns reported by Chinese patients with borderline personality disorder.
Int J Psychol
PUBLISHED: 05-10-2014
Show Abstract
Hide Abstract
The primary purposes of this study were to (1) compare the characteristics of childhood experiences of parental rearing patterns in China reported by patients with borderline personality disorder (BPD), patients with other personality disorders and patients without personality disorders; (2) identify the reported parental rearing patterns associated with BPD in China; and (3) determine whether these patterns differ for males and females. One hundred and fifty-two patients with BPD, 79 patients with other personality disorders and 55 patients without Axis II diagnoses were administered the Chinese version of the McLean Screening Instrument for BPD and completed the Egna Minnen av Barndoms Uppfostran (EMBU), a self-report measure of childhood parental rearing patterns. Parental rearing patterns reported by the BPD group were characterized by less emotional warmth, and greater punishment, rejection and control than patterns reported by the other two groups. Within the BPD group, males were more likely than females to report parental punishment, rejection and control. Paternal punishment, low maternal emotional warmth and female gender predicted BPD diagnosis. Negative parental rearing patterns appear to contribute to the development of BPD in China and vary with the gender of the child. Maternal emotional warmth may be a protective factor against BPD.
Related JoVE Video
Nanomechanical properties of poly(l-lactide) nanofibers after deformation.
Colloids Surf B Biointerfaces
PUBLISHED: 05-09-2014
Show Abstract
Hide Abstract
Atomic force microscopy (AFM) technique was used to investigate the nanomechanical properties of poly(l-lactide) (PLLA) nanofibers produced by the thermally induced phase separation (TIPS) method. Firstly, AFM-based nanolithography was employed to produce localized deformations on the surface of single PLLA nanofiber, in which the AFM tip served as a nanoscale burin to draw a scratch longitudinally along the nanofiber. Secondly, the morphology and physical properties of the nanofiber before and immediately after the deformation were characterized with AFM and force spectroscopy measurement. During the initial stage of TIPS process, the crystallization of PLLA resulted in a regular arrangement of crystalline domains along the thinner fibrils which then assembled laterally into larger nanofibers. The deformation due to the nanoindentation and plowing with the probe induced structural variation of PLLA nanofibers and led to a functional consequence in their nanomechanical properties. The region after deformation had a higher adhesion force and elastic modulus, probably because the polymer chains became more compact and ordered under both compression and shear stresses.
Related JoVE Video
"Click" immobilization of a VEGF-mimetic peptide on decellularized endothelial extracellular matrix to enhance angiogenesis.
ACS Appl Mater Interfaces
PUBLISHED: 05-01-2014
Show Abstract
Hide Abstract
We show that coating of decellularized extracellular matrix (DC-ECM) on substrate surfaces is an efficient way to generate a platform mimicking the native ECM environment. Moreover, the DC-ECM can be modified with a peptide (QK) mimicking vascular endothelial growth factor without apparently compromising its integrity. The modification was achieved through metabolic incorporation of a "clickable" handle to DC-ECM followed by rapid attachment of the QK peptide with an azido tag using copper-catalyzed click reaction. The attachment of the QK peptide on to DC-ECM in this way further enhanced the angiogenic responses (formation of branched tubular networks) of endothelial cells.
Related JoVE Video
[Proximal gastrectomy versus total gastrectomy for adenocarcinoma of esophagogastric junction: a meta-analysis].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 04-25-2014
Show Abstract
Hide Abstract
To compare the efficacy of proximal gastrectomy(PG) and total gastrectomy(TG) for adenocarcinoma of esophagogastric junction.
Related JoVE Video
[An alternative model of composite tissue transplantation in rat: the femur osteomyocutaneous flap].
Zhonghua Zheng Xing Wai Ke Za Zhi
PUBLISHED: 04-24-2014
Show Abstract
Hide Abstract
To reconstruct a simpler and reliable composite tissue transplantation model-the femur osteomyocutaneous flap for the replacement of hindlimb transplantation.
Related JoVE Video
The association of phosphatase and tensin homolog deleted on chromosome 10 polymorphisms and lifestyle habits with colorectal cancer risk in a Chinese population.
Tumour Biol.
PUBLISHED: 04-22-2014
Show Abstract
Hide Abstract
The PI3K signaling pathway plays an important role in the development of colorectal cancer (CRC) and other neoplasm. Somatic phosphatase and tensin homolog deleted on chromosome 10 (PTEN) mutations and deletions or epigenetic silencing have been observed in multiple tumor types including CRC. To assess the association of PTEN polymorphisms and lifestyle habits with CRC risk in Chinese population, we carried out a case-control study which included 545 cases and 522 controls. In the present study, we genotyped eight single-nucleotide polymorphisms (SNPs) in PTEN and found that rs11202607 was associated with increased CRC risk (odds ratio (OR)?=?1.40, 95 % confidence interval (CI)?=?1.04-1.90). Stratification analysis by lifestyle habits showed a stronger association between rs11202607 and CRC risk among never tea drinkers than that among tea-drinkers (OR?=?2.04, 95 % CI 1.29-3.22), and significant additive interaction between rs10490920 and tea drinking status was observed. Our study provided the evidence of an association between PTEN polymorphisms and the risk of CRC and significant additive interaction between PTEN polymorphism and tea drinking. Studies with larger sample size and further investigations into the mechanism are warranted to clarify the role of PTEN in colorectal carcinogenesis and the association between PTEN genetic variations, environment exposure, and CRC risk.
Related JoVE Video
Biological protein-resistance layer construction of recombinant hirudin on polymethyl methacrylate IOL surface.
J Biomed Mater Res A
PUBLISHED: 04-11-2014
Show Abstract
Hide Abstract
In this article, the surface of intraocular len material PMMA was first aminated for activation on which some polar groups generated such as C?N, COO(-) , ?OH, NH3 (+) , etc. Then the anticoagulant drugs recombinant hirudin (rH) was grafted with amido bonds to look forward to resist the adsorption of nonspecific protein or cells in tear, even the cataract. The detailed analysis and discussion about the grafting quantity, molography, wettability, electric charges, chemical structure, and the dynamic adsorption of protein Fn on the material surface were carried on by the technology of ultraviolet photometric, contact angle, solid Zeta potential, X-ray photoelectron spectroscopy, and quartz crystal microbalance. The surface with a certain amount of rH modification existed more hydrophilic due to the amphiphilic structure than before, on which the protein adsorption was the most unstable. The results indicated that the rH modification improved the resistance of PMMA to nonspecific adsorption of protein Fn to achieve the expectative effect. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2014.
Related JoVE Video
Hiwi downregulation, mediated by shRNA, reduces the proliferation and migration of human hepatocellular carcinoma cells.
Mol Med Rep
PUBLISHED: 04-01-2014
Show Abstract
Hide Abstract
The Piwi subfamily is one of two Argonaute family proteins, which are characterized by the presence of Piwi and Piwi?Argonaute?Zwille domains, and are well known for their role in RNA silencing. Hiwi, a human member of the Piwi subfamily, is restricted to the germ line, where it binds Piwi?interacting RNAs and functions in stem cell self?renewal and gametogenesis. Previous reports have indicated that abnormal Hiwi expression may be associated with a poor prognosis of numerous types of human cancer, including hepatocellular carcinoma (HCC). However, little is currently known about the oncogenic role of Hiwi in HCC. In the present study, it was confirmed that Hiwi is overexpressed at both the mRNA and protein level, in HCC specimens, as well as in MHCC97L and MHCC97H HCC cell lines. A lentivirus?mediated small hairpin rna (shRNA) targeting Hiwi was constructed and used to infect MHCC97L and MHCC97H cells. Relative Hiwi mRNA and protein expression levels were determined by quantitative polymerase chain reaction and western blot analysis, respectively. Cell proliferation, migration and invasion were determined using cell count, scratch and Transwell assays, respectively. Hiwi mRNA and protein expression was significantly downregulated in HCC cells in response to transduction with the lentivirus?mediated shRNA. Furthermore, the proliferative, migrative and invasive properties of the shRNA?transduced cells were significantly decreased. Therefore, Hiwi downregulation mediated by shRNA, may reduce the proliferation and migration of HCC cells. These results indicate that Hiwi may have an important role in the progression of HCC and may be a target for anticancer therapy.
Related JoVE Video
Improving the mechanical properties of collagen-based membranes using silk fibroin for corneal tissue engineering.
J Biomed Mater Res A
PUBLISHED: 04-01-2014
Show Abstract
Hide Abstract
Although collagen with outstanding biocompatibility has promising application in corneal tissue engineering, the mechanical properties of collagen-based scaffolds, especially suture retention strength, must be further improved to satisfy the requirements of clinical applications. This article describes a toughness reinforced collagen-based membrane using silk fibroin. The collagen-silk fibroin membranes based on collagen [silk fibroin (w/w) ratios of 100:5, 100:10, and 100:20] were prepared by using silk fibroin and cross-linking by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. These membranes were analyzed by scanning electron microscopy and their optical property, and NaCl and tryptophan diffusivity had been tested. The water content was found to be dependent on the content of silk fibroin, and CS10 membrane (loading 10 wt % of silk fibroin) performed the optimal mechanical properties. Also the suture experiments have proved CS10 has high suture retention strength, which can be sutured in rabbit eyes integrally. Moreover, the composite membrane proved good biocompatibility for the proliferation of human corneal epithelial cells in vitro. Lamellar keratoplasty shows that CS10 membrane promoted complete epithelialization in 35 ± 5 days, and their transparency is restored quickly in the first month. Corneal rejection reaction, neovascularization, and keratoconus are not observed. The composite films show potential for use in the field of corneal tissue engineering. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2014.
Related JoVE Video
Association of a genetic variant in microRNA-146a with risk of colorectal cancer: a population-based case-control study.
Tumour Biol.
PUBLISHED: 04-01-2014
Show Abstract
Hide Abstract
MicroRNAs (miRNAs) are small non-coding RNAs that negatively regulate target gene expression at the posttranscriptional level. Although recent studies have indicated that miR-146a is involved in the tumorigenesis of various types of malignancies, few studies have investigated its role in colorectal cancer. In the current study, we examined the expression of miR-146a in colorectal cancer tissue and adjacent normal controls using publicly available expression profiling data. We then conducted a population-based case-control study which included 554 colorectal cancer cases and 566 matched healthy controls to assess the association of a genetic variant (rs2910164) in miR-146a with colorectal cancer susceptibility. We observed decreased expression of miR-146a in rectal cancer tissue compared with adjacent normal controls (P < 0.001). Association between miR-146a rs2910164 polymorphism and risk of colorectal cancer was detected with effect modification by alcohol drinking status (P for interaction = 0.010). Among non-alcohol drinkers, individuals with CC/CG genotype had an increased risk of developing colorectal cancer compared with those carrying GG genotype (odds ratio (OR) = 1.63, 95 % confidence interval (CI): 1.07 ? 2.47). Our findings indicate an association between miR-146a dysregulation and colorectal cancer, and suggest that miR-146a may play a role in colorectal carcinogenesis. Further large population-based prospective studies as well as mechanistic investigations are warranted to validate our findings.
Related JoVE Video
Minocycline alleviates behavioral deficits and inhibits microglial activation in the offspring of pregnant mice after administration of polyriboinosinic-polyribocytidilic acid.
Psychiatry Res
PUBLISHED: 03-20-2014
Show Abstract
Hide Abstract
Epidemiological studies have indicated that maternal infection during pregnancy may lead to a higher incidence of schizophrenia in the offspring. Activation of microglia is a key event in the reaction of the cerebral immune system to pathological changes. It can be hypothesized that microglia contribute to the neuropathology of schizophrenia. In this study, at embryonic day (ED) 9 pregnant mice were treated with intraperitoneal injection of polyriboinosinic-polyribocytidilic acid (Poly I:C) at a single dose of 20 mg/kg. At postnatal day 42, descendants were treated with minocycline (40 mg/kg) or saline for consecutive 14 days. Behavioral changes (locomotor activity, social interaction, and prepulse inhibition) were examined and the number of microglia was assessed after the treatment. The adult offspring exposed to Poly I:C at ED 9 showed behavioral changes (hyperlocomotion, deficits in social interaction and prepulse inhibition) and significant microglial activation in these brain areas (hippocampus, thalamus, and cerebral cortex) compared to those in saline-injected group. Moreover, minocycline attenuated the behavioral deficits and inhibited the activated microglia. These findings suggest that maternal infection may contribute to microglial activation in the offspring. In addition, the effect of minocycline in this immune model may be related to the inhibition of microglial activation.
Related JoVE Video
Sludge reduction and performance analysis of a modified sludge reduction process.
Water Sci. Technol.
PUBLISHED: 03-14-2014
Show Abstract
Hide Abstract
A modified sludge process reduction activated sludge (SPRAS) technology was developed by inserting a sludge process reduction (SPR) module, composed of an aeration tank and a settler, before the activated sludge system was proposed in this study. Compared with the anaerobic/anoxic/aerobic (AAO) process, the SPRAS resulted in a remarkable decrease in sludge production by 76.6%; sludge decay owing to lengthy solids retention time (about 121.5 d) could be the major cause. During the 217-day operation, the oxidation-reduction potential (ORP) (from 54 to -198 mV) and pH (from 7.8 to 5.0) at the bottom of the SPR settler gradually decreased, and low ORP and pH were in favor of sludge reduction in the SPRAS system. The insertion of the SPR module improved the removal efficiencies of suspended solids, chemical oxygen demand and ammonium nitrogen, and total nitrogen concentration in the effluent was reduced from 23.89 ± 4.82 to 14.16 ± 3.98 mg/L by 50% influent bypassing the SPR module. These results indicated that the SPRAS process could produce much less excess sludge and guarantee better effluent quality than the AAO process.
Related JoVE Video
Phase II trial of bortezomib plus doxorubicin in hepatocellular carcinoma (E6202): a trial of the Eastern Cooperative Oncology Group.
Invest New Drugs
PUBLISHED: 03-05-2014
Show Abstract
Hide Abstract
To evaluate the efficacy and tolerability of bortezomib in combination with doxorubicin in patients with advanced hepatocellular carcinoma, and to correlate pharmacodynamic markers of proteasome inhibition with response and survival.
Related JoVE Video
Evaluation of insulin medium or chondrogenic medium on proliferation and chondrogenesis of ATDC5 cells.
Biomed Res Int
PUBLISHED: 03-04-2014
Show Abstract
Hide Abstract
The ATDC5 cell line is regarded as an excellent cell model for chondrogenesis. In most studies with ATDC5 cells, insulin medium (IM) was used to induce chondrogenesis while chondrogenic medium (CM), which was usually applied in chondrogenesis of mesenchymal stem cells (MSCs), was rarely used for ATDC5 cells. This study was mainly designed to investigate the effect of IM, CM, and growth medium (GM) on chondrogenesis of ATDC5 cells.
Related JoVE Video
In situ synthesis of robust conductive cellulose/polypyrrole composite aerogels and their potential application in nerve regeneration.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 02-24-2014
Show Abstract
Hide Abstract
Nanostructured conductive polymers can offer analogous environments for extracellular matrix and induce cellular responses by electric stimulation, however, such materials often lack mechanical strength and tend to collapse under small stresses. We prepared electrically conductive nanoporous materials by coating nanoporous cellulose gels (NCG) with polypyrrole (PPy) nanoparticles, which were synthesized in?situ from pyrrole monomers supplied as vapor. The resulting NCG/PPy composite hydrogels were converted to aerogels by drying with supercritical CO2, giving a density of 0.41-0.53?g?cm(-3), nitrogen adsorption surface areas of 264-303?m(2) g(-1), and high mechanical strength. The NCG/PPy composite hydrogels exhibited an electrical conductivity of up to 0.08?S?cm(-1). In?vitro studies showed that the incorporation of PPy into an NCG enhances the adhesion and proliferation of PC12 cells. Electrical stimulation demonstrated that PC12 cells attached and extended longer neurites when cultured on NCG/PPy composite gels with DBSA dopant. These materials are promising candidates for applications in nerve regeneration, carbon capture, catalyst supports, and many others.
Related JoVE Video
Shuganjieyu capsule increases neurotrophic factor expression in a rat model of depression.
Neural Regen Res
PUBLISHED: 02-22-2014
Show Abstract
Hide Abstract
Shuganjieyu capsule has been approved for clinical treatment by the State Food and Drug Ad-ministration of China since 2008. In the clinic, Shuganjieyu capsule is often used to treat mild to moderate depression. In the rat model of depression established in this study, Shuganjieyu capsule was administered intragastrically daily before stress. Behavioral results confirmed that depressive symptoms lessened after treatment with high-dose (150 mg/kg) Shuganjieyu capsule. Immunohistochemistry results showed that high-dose Shuganjieyu capsule significantly increased phosphorylation levels of phosphorylation cyclic adenosine monophosphate response element binding protein and brain-derived neurotrophic factor expression in the medial prefrontal cortex and hippocampal CA3 area. Overall, our results suggest that in rats, Shuganjieyu capsule effec-tively reverses depressive-like behaviors by increasing expression levels of neurotrophic factors in the brain.
Related JoVE Video
A label-free amperometric immunosensor for detection of zearalenone based on trimetallic Au-core/AgPt-shell nanorattles and mesoporous carbon.
Anal. Chim. Acta
PUBLISHED: 02-19-2014
Show Abstract
Hide Abstract
A novel label-free amperometric immunosensor is proposed for the ultrasensitive detection of zearalenone (ZEN) based on mesoporous carbon (MC) and trimetallic nanorattles (core/shell particles with movable cores encapsulated in the shells). The nanorattles are composed of special Au-core and imperfect AgPt-shell structure (Au@AgPt). The Au@AgPt nanorattles are loaded onto the MC by physical adsorption. The structure of the Au@AgPt nanorattles was characterized by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Energy dispersive X-ray spectroscopy (EDS) confirmed the composition of the synthesized nanorattles. Compared with monometallic and bimetallic nanoparticles (NPs), Au@AgPt nanorattles show a higher electron transfer rate due to the synergistic effect of the Au, Ag and Pt NPs. MC further improves the sensitivity of the immunosensor because of its extraordinarily large specific surface area, suitable pore arrangement and outstanding conductivity. The large specific surface area of MC and MC@Au@AgPt were characterized by the BET method. ZEN antibodies are immobilized onto the nanorattles via Ag-NH2 bonds and Pt-NH2 bonds. Cyclic voltammetry and square wave voltammetry were used to characterize the recognizability of ZEN. Under optimum experimental conditions, the proposed immunosensor exhibited a low detection limit (1.7 pg mL(-1)), a wide linear range (from 0.005 to 15 ng mL(-1)) as well as good stability, reproducibility and selectivity. The sensor can be used in clinical analysis.
Related JoVE Video
The value of Apolipoprotein B/Apolipoprotein A1 ratio for metabolic syndrome diagnosis in a Chinese population: a cross-sectional study.
Lipids Health Dis
PUBLISHED: 02-18-2014
Show Abstract
Hide Abstract
The apoB/apoA1 ratio has been reported to be associated with the metabolic syndrome (MetS), and it may be a more convenient biomarker in MetS predicting. However, whether apoB/apoA1 ratio is a better indicator of metabolic syndrome than other biomarkers and what is the optimal cut-off value of apoB/apoA1 ratio as an indicator of metabolic syndrome in Chinese population remain unknown. Thus, we carried out the current study to assess the predictive value of apoB/apoA1 ratio and determine the optimal cut-off value of apoB/apoA1 ratio for diagnosing MetS in a Chinese population.
Related JoVE Video
[Cytogenetic and molecular study of a patient with severe oligozoospermia and asthenozoospermia].
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
PUBLISHED: 02-11-2014
Show Abstract
Hide Abstract
To explore genetic etiologies of a patient with severe oligozoospermia and asthenozoospermia.
Related JoVE Video
Analysis of chemotherapy dosage and dosage intensity and survival outcomes of high-grade osteosarcoma patients younger than 40 years.
Clin Ther
PUBLISHED: 01-27-2014
Show Abstract
Hide Abstract
Chemotherapy is essential for long-term survival of osteosarcoma patients. However, the impact of dosage and dosage intensity (DI) of chemotherapeutic agents on patients with high-grade osteosarcoma is largely unknown.
Related JoVE Video
PHBV/PAM scaffolds with local oriented structure through UV polymerization for tissue engineering.
Biomed Res Int
PUBLISHED: 01-22-2014
Show Abstract
Hide Abstract
Locally oriented tissue engineering scaffolds can provoke cellular orientation and direct cell spread and migration, offering an exciting potential way for the regeneration of the complex tissue. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) scaffolds with locally oriented hydrophilic polyacrylamide (PAM) inside the macropores of the scaffolds were achieved through UV graft polymerization. The interpenetrating PAM chains enabled good interconnectivity of PHBV/PAM scaffolds that presented a lower porosity and minor diameter of pores than PHBV scaffolds. The pores with diameter below 100? ?m increased to 82.15% of PHBV/PAM scaffolds compared with 31.5% of PHBV scaffolds. PHBV/PAM scaffold showed a much higher compressive elastic modulus than PHBV scaffold due to PAM stuffing. At 5 days of culturing, sheep chondrocytes spread along the similar direction in the macropores of PHBV/PAM scaffolds. The locally oriented PAM chains might guide the attachment and spreading of chondrocytes and direct the formation of microfilaments via contact guidance.
Related JoVE Video
Polar-coordinate lattice Boltzmann modeling of compressible flows.
Phys Rev E Stat Nonlin Soft Matter Phys
PUBLISHED: 01-21-2014
Show Abstract
Hide Abstract
We present a polar coordinate lattice Boltzmann kinetic model for compressible flows. A method to recover the continuum distribution function from the discrete distribution function is indicated. Within the model, a hybrid scheme being similar to, but different from, the operator splitting is proposed. The temporal evolution is calculated analytically, and the convection term is solved via a modified Warming-Beam (MWB) scheme. Within the MWB scheme a suitable switch function is introduced. The current model works not only for subsonic flows but also for supersonic flows. It is validated and verified via the following well-known benchmark tests: (i) the rotational flow, (ii) the stable shock tube problem, (iii) the Richtmyer-Meshkov (RM) instability, and (iv) the Kelvin-Helmholtz instability. As an original application, we studied the nonequilibrium characteristics of the system around three kinds of interfaces, the shock wave, the rarefaction wave, and the material interface, for two specific cases. In one of the two cases, the material interface is initially perturbed, and consequently the RM instability occurs. It is found that the macroscopic effects due to deviating from thermodynamic equilibrium around the material interface differ significantly from those around the mechanical interfaces. The initial perturbation at the material interface enhances the coupling of molecular motions in different degrees of freedom. The amplitude of deviation from thermodynamic equilibrium around the shock wave is much higher than those around the rarefaction wave and material interface. By comparing each component of the high-order moments and its value in equilibrium, we can draw qualitatively the main behavior of the actual distribution function. These results deepen our understanding of the mechanical and material interfaces from a more fundamental level, which is indicative for constructing macroscopic models and other kinds of kinetic models.
Related JoVE Video
A microfluidic-enabled mechanical microcompressor for the immobilization of live single- and multi-cellular specimens.
Microsc. Microanal.
PUBLISHED: 01-21-2014
Show Abstract
Hide Abstract
A microcompressor is a precision mechanical device that flattens and immobilizes living cells and small organisms for optical microscopy, allowing enhanced visualization of sub-cellular structures and organelles. We have developed an easily fabricated device, which can be equipped with microfluidics, permitting the addition of media or chemicals during observation. This device can be used on both upright and inverted microscopes. The apparatus permits micrometer precision flattening for nondestructive immobilization of specimens as small as a bacterium, while also accommodating larger specimens, such as Caenorhabditis elegans, for long-term observations. The compressor mount is removable and allows easy specimen addition and recovery for later observation. Several customized specimen beds can be incorporated into the base. To demonstrate the capabilities of the device, we have imaged numerous cellular events in several protozoan species, in yeast cells, and in Drosophila melanogaster embryos. We have been able to document previously unreported events, and also perform photobleaching experiments, in conjugating Tetrahymena thermophila.
Related JoVE Video
Neonatal intrahippocampal injection of lipopolysaccharide induces deficits in social behavior and prepulse inhibition and microglial activation in rats: Implication for a new schizophrenia animal model.
Brain Behav. Immun.
PUBLISHED: 01-18-2014
Show Abstract
Hide Abstract
Several lines of evidence have suggested that the dysregulation of immune system is involved in the pathogenesis of schizophrenia. Microglia are the resident macrophage of the brain and the major player in innate immunity in the brain. We hypothesized that microglia activation may be closely associated with the neuropathology of schizophrenia. Neonatal intrahippocampal injection of lipopolysaccharide (LPS), an activator of microglia, was performed in rats at postnatal day 7 (PD7), and they were separately treated with saline or minocycline for consecutive 3days. Behavioral changes (locomotor activity, social interaction and prepulse inhibition) were examined in adulthood, and the number of microglia was assessed using immunohistochemistry at PD9, PD21 and PD67. The adult rats in LPS-injected group showed obvious behavioral alterations (deficits in social behavior and prepulse inhibition) and a persistently dramatic increase of number of activated microglial cells in the hippocampus, cerebral cortex and thalamus compared to those in saline-injected group. Interestingly, pretreatment with minocycline could significantly rescue the behavioral deficits and prevent microglia activation. Our results suggest that neonatal intrahippocampal LPS injection may serve as a potential schizophrenia animal model, and inhibition of microglia activation may be a potential treatment strategy for schizophrenia.
Related JoVE Video
Differential expression of caveolin-1 in human myometrial and uterine leiomyoma smooth muscle.
Am. J. Obstet. Gynecol.
PUBLISHED: 01-09-2014
Show Abstract
Hide Abstract
Uterine leiomyomas, the most common neoplasms of the female genital tract, are benign tumors of the uterus arising from the smooth muscle cells (SMCs) of the myometrium with an involvement of estrogen. Caveolin-1 (Cav-1), a major protein component in caveolae membrane lipid rafts, is down-regulated in several estrogen-related cancer cells, and overexpression of Cav-1 inhibits proliferation of cancer cells and vascular SMCs as well. Therefore, we hypothesize that Cav-1 is down-regulated in human uterine leiomyoma.
Related JoVE Video
Minocycline supplementation for treatment of negative symptoms in early-phase schizophrenia: a double blind, randomized, controlled trial.
Schizophr. Res.
PUBLISHED: 01-07-2014
Show Abstract
Hide Abstract
It is difficult to improve negative symptoms and cognitive impairments in schizophrenia. A previous pilot study has shown that minocycline, a semi-synthetic second-generation tetracycline, is effective in treating for negative and/or cognitive symptoms in schizophrenia.
Related JoVE Video
Alcohol drinking and upper aerodigestive tract cancer mortality: a systematic review and meta-analysis.
Oral Oncol.
PUBLISHED: 01-07-2014
Show Abstract
Hide Abstract
Upper aerodigestive tract (UADT) cancer is among the most frequent cancer and the most common death causes of cancer in the world. Epidemiological studies have reported an inconsistent relationship between alcohol drinking and UADT cancer mortality. However, no systematic review or meta-analysis has been reported up to now. To quantify the association between alcohol drinking and UADT cancer mortality, we performed this meta-analysis.
Related JoVE Video
When Cri du chat syndrome meets Edwards syndrome.
Mol Med Rep
PUBLISHED: 01-06-2014
Show Abstract
Hide Abstract
It has been well established that the 5p deletion causes Cri du chat syndrome, typically characterized by a cat?like cry, and that duplication of 18q causes Edwards syndrome; the two are rare genetic abnormalities that separately lead to physical and mental impairments. However, the severity of the clinicopathological characteristics that arise when these two aberrations occur in one patient is unknown. Here, the first case in our knowledge of a single patient (a two?year?old female) with 5p partial monosomy and 18q partial trisomy is described. In the present study, chromosome microarray analysis was performed, which identified the imbalance of chromosomes 5 and 18 in the patient. The chromosome aberrations were further confirmed by fluorescence in situ hybridization. By comparing the phenotypes of combined case with those of the individual syndromes, severe clinical phenotypes of the 5p (5p15.33?p13.3) deletion were confirmed, however, the net effect of the duplication of 18q22.3?q23 was not determined, as this duplication only appeared to have a weak effect on the patient's phenotypes. The correlation between these chromosomal aberrations and their clinical features has implications for the identification of critical regions of 5p and 18q, particularly for the functional mapping of chromosome 18.
Related JoVE Video
High-throughput fluorescence-activated cell sorting for lipid hyperaccumulating Chlamydomonas reinhardtii mutants.
Plant Biotechnol. J.
PUBLISHED: 01-03-2014
Show Abstract
Hide Abstract
The genetically tractable microalga Chlamydomonas reinhardtii has many advantages as a model for renewable bioproducts and/or biofuels production. However, one limitation of C. reinhardtii is its relatively low-lipid content compared with some other algal species. To overcome this limitation, we combined ethane methyl sulfonate mutagenesis with fluorescence-activated cell sorting (FACS) of cells stained with the lipophilic stain Nile Red to isolate lipid hyperaccumulating mutants of C. reinhardtii. By manipulating the FACS gates, we sorted mutagenized cells with extremely high Nile Red fluorescence signals that were rarely detected in nonmutagenized populations. This strategy successfully isolated several putative lipid hyperaccumulating mutants exhibiting 23% to 58% (dry weight basis) higher fatty acid contents than their progenitor strains. Significantly, for most mutants, nitrogen starvation was not required to attain high-lipid content nor was there a requirement for a deficiency in starch accumulation. Microscopy of Nile Red stained cells revealed that some mutants exhibit an increase in the number of lipid bodies, which correlated with TLC analysis of triacyglycerol content. Increased lipid content could also arise through increased biomass production. Collectively, our findings highlight the ability to enhance intracellular lipid accumulation in algae using random mutagenesis in conjunction with a robust FACS and lipid yield verification regime. Our lipid hyperaccumulating mutants could serve as a genetic resource for stacking additional desirable traits to further increase lipid production and for identifying genes contributing to lipid hyperaccumulation, without lengthy lipid-induction periods.
Related JoVE Video
Cloning of seed dormancy genes (TaSdr) associated with tolerance to pre-harvest sprouting in common wheat and development of a functional marker.
Theor. Appl. Genet.
PUBLISHED: 01-03-2014
Show Abstract
Hide Abstract
After cloning and mapping of wheat TaSdr genes, both the functional markers for TaSdr - B1 and TaVp - 1B were validated, and the distribution of allelic variations at TaSdr - B1 locus in the wheat cultivars from 19 countries was characterized. Seed dormancy is a major factor associated with pre-harvest sprouting (PHS) in common wheat (Triticum aestivum L.). Wheat TaSdr genes, orthologs of OsSdr4 conferring seed dormancy in rice, were cloned by a comparative genomics approach. They were located on homoeologous group 2 chromosomes, and designated as TaSdr-A1, TaSdr-B1 and TaSdr-D1, respectively. Sequence analysis of TaSdr-B1 revealed a SNP at the position -11 upstream of the initiation codon, with bases A and G in cultivars with low and high germination indices (GI), respectively. A cleaved amplified polymorphism sequence marker Sdr2B was developed based on the SNP, and subsequently functional analysis of TaSdr-B1 was conducted by association and linkage mapping. A QTL for GI co-segregating with Sdr2B explained 6.4, 7.8 and 8.7 % of the phenotypic variances in a RIL population derived from Yangxiaomai/Zhongyou 9507 grown in Shijiazhuang, Beijing and the averaged data from those environments, respectively. Two sets of Chinese wheat cultivars were used for association mapping, and results indicated that TaSdr-B1 was significantly associated with GI. Analysis of the allelic distribution at the TaSdr-B1 locus showed that the frequencies of TaSdr-B1a associated with a lower GI were high in cultivars from Japan, Australia, Argentina, and the Middle and Lower Yangtze Valley Winter Wheat Region and Southwest Winter Wheat Region in China. This study provides not only a reliable functional marker for molecular-assisted selection of PHS in wheat breeding programs, but also gives novel information for a comprehensive understanding of seed dormancy.
Related JoVE Video
HMGB1 enhances embryonic neural stem cell proliferation by activating the MAPK signaling pathway.
Biotechnol. Lett.
PUBLISHED: 01-02-2014
Show Abstract
Hide Abstract
Neural stem cells (NSCs) are involved in neural tube formation. As the high-mobility group box 1 (HMGB1) protein is involved in neurulation and is present at elevated levels in neural tube defects (NTDs) induced by hyperthermia, we have now investigated the effects of HMGB1 on proliferation, differentiation, and MAPK signaling pathways of NSCs in vitro. We constructed a lentivirus vector with HMGB1 siRNA and used it to infect NSCs. Down-regulation of HMGB1 expression was confirmed. Proliferation of NSCs was determined by MTS and nestin/BrdU double-labeling. Differentiation of NSCs was assessed using ?-tubulinIII and GFAP. Knockdown of HMGB1 significantly suppressed NSC proliferation but hardly affected differentiation, which was regulated by decreased expression of MAPK signaling pathways. Thus, HMGB1 has beneficial effects on neurulation and may serve as a new target for the prevention of NTDs.
Related JoVE Video
Synthesis of 2-trifluoromethylpyrazolo[5,1-a]isoquinolines via silver triflate-catalyzed or electrophile-mediated one-pot tandem reaction.
Beilstein J Org Chem
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
An efficient one-pot tandem cyclization/[3 + 2] cycloaddition reaction of N'-(2-alkynylbenzylidene)hydrazides with ethyl 4,4,4-trifluorobut-2-ynoate under silver triflate-catalyzed or electrophile-mediated conditions is described. Various trifluoromethylated pyrazolo[5,1-a]isoquinolines were afforded in moderate to excellent yield by this developed method.
Related JoVE Video
Identification of glyceraldehyde 3-phosphate dehydrogenase sequence and expression profiles in tree shrew (Tupaia belangeri).
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
The tree shrews (Tupaia belangeri) diverged from the primate order (Primates) and are classified as Scandentia, a separate taxonomic group of mammals. The tree shrew has been suggested to use an animal model to study human disease but the genomic sequences of tree shrew is largely unidentified. Here we identified the full-length cDNA sequence of a housekeeping gene, Glyceraldehyde 3-phosphate Dehydrogenase (GAPDH), in tree shrew. We further constructed a phylogenetic family tree base on GAPDH molecules of various organisms and compared GAPDH sequences with human and other small experimental animals. These study revealed that tree shrew was closer to human than mouse, rat, rabbit and guinea pig. The Quantitative Reverse Transcription PCR and western blot analysis further demonstrated that GAPDH expressed in various tissues in tree shrew as a general conservative housekeeping proteins as in human. Our findings provide the novel genetic knowledge of the tree shrew and strong evidences that tree shrew can be an experimental model system to study human disorders.
Related JoVE Video
Minocycline and risperidone prevent microglia activation and rescue behavioral deficits induced by neonatal intrahippocampal injection of lipopolysaccharide in rats.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Various signs of activation of microglia have been reported in schizophrenia, and it is hypothesized that microglia activation is closely associated with the neuropathology of schizophrenia.
Related JoVE Video
Prognostic role of pre-treatment serum AFP-L3% in hepatocellular carcinoma: systematic review and meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Serum lens culinaris agglutinin-reactive fraction of ?-fetoprotein (AFP-L3%) has been widely used for HCC diagnosis and follow-up surveillance as tumor serologic marker. However, the prognostic value of high pre-treatment serum AFP-L3% in patients with hepatocellular carcinoma (HCC) remains controversial. We therefore conduct a meta-analysis to assess the relationship between high pre-treatment serum AFP-L3% and clinical outcome of HCC.
Related JoVE Video
Enhancement of fat graft survival by bone marrow-derived mesenchymal stem cell therapy.
Plast. Reconstr. Surg.
PUBLISHED: 10-30-2013
Show Abstract
Hide Abstract
Adipose-derived stem cells can improve fat graft survival, but there is no literature reporting whether bone marrow-derived mesenchymal stem cells enhance fat graft survival. The authors explored the feasibility of enhancing fat graft survival using bone marrow-derived mesenchymal stem cells.
Related JoVE Video
Morphological Features of Cell Death and Tissue Remolding of Fat Grafts.
Ann Plast Surg
PUBLISHED: 10-24-2013
Show Abstract
Hide Abstract
Fat tissue graft has been commonly used for soft tissue augmentation. However, the mechanisms underlying the maintenance of graft volume and weight are still unclear. As morphological features provide direct evidences for cell death and survival, we aimed to investigate the fate of grafted adipocytes and the dynamic changes in the remodeling of adipose tissues by transmission electron microscopy technique.
Related JoVE Video
ATDC5: an excellent in vitro model cell line for skeletal development.
J. Cell. Biochem.
PUBLISHED: 10-18-2013
Show Abstract
Hide Abstract
The ATDC5 cell line is derived from mouse teratocarcinoma cells and characterized as a chondrogenic cell line which goes through a sequential process analogy to chondrocyte differentiation. Thus, it is regarded as a promising in vitro model to study the factors that influence cell behaviors during chondrogenesis. It also provides insights in exploring signaling pathways related to skeletal development as well as interactions with innovative materials. To date, over 200 studies have utilized ATDC5 to obtain lots of significant findings. In this review, we summarized the literature of ATDC5 related studies and emphasized the application of ATDC5 in chondrogenesis. In addition, the general introduction of ATDC5 including its derivation and characterization is covered in this article.
Related JoVE Video
Expression of metallothionein of freshwater crab (Sinopotamon henanense) in Escherichia coli enhances tolerance and accumulation of zinc, copper and cadmium.
Ecotoxicology
PUBLISHED: 10-14-2013
Show Abstract
Hide Abstract
Metallothioneins (MTs) are ubiquitous metal-binding, cysteine-rich, small proteins and play a major role in metal homeostasis and/or detoxification in all organisms. In a previous study, a novel full length MT gene was isolated from the freshwater crab (Sinopotamon henanense), a species widely distributed in Shanxi and Henan Provinces, China. In this report, the gene for the crab MT was inserted into a PET-28a-6His-SUMO vector and recombinant soluble MT was over-expressed as fusions with SUMO in Escherichia coli. The recombinant fusion protein was purified by affinity chromatography and its biochemical properties were analyzed. In addition, on the basis of constructing SUMO-MT, two mutants, namely SUMO-MTt1 and SUMO-MTt2, were constructed to change the primary structure of SUMO-MT using site-directed mutagenesis techniques with the amino acid substitutions D3C and S37C in order to increase metal-binding capacity of MT. E. coli cells expressing SUMO-MT and these single-mutant proteins exhibited enhanced metal tolerance and higher accumulation of metal ions than control cells. The results showed that the bioaccumulation and tolerance of Zn(2+), Cu(2+) and Cd(2+) in these strains followed the decreasing order of SUMO-MTt1 > SUMO-MTt2 > SUMO-MT. E. coli cells have low tolerance and high accumulation towards cadmium compared to zinc and copper. These results show that the MT of S. henanense could enhance tolerance and accumulation of metal ions. Moreover, we were able to create a novel protein based on the crab MT to bind metal ions at high density and with high affinity. Therefore, SUMO-MT and its mutants can provide potential candidates for heavy metal bioremediation. This study could help further elucidate the mechanism of how the crab detoxifies heavy metals and provide a scientific basis for environment bioremediation of heavy metal pollution using the over-expression of the crab MT and mutant proteins.
Related JoVE Video
Biochemical, histological and ultrastructural alterations of the alimentary system in the freshwater crab Sinopotamon henanense subchronically exposed to cadmium.
Ecotoxicology
PUBLISHED: 10-10-2013
Show Abstract
Hide Abstract
Cadmium (Cd) is one of the toxic metals in the aquatic environment. We investigated the effects of Cd on the digestive enzymes, antioxidant enzymes, malondialdehyde (MDA) content and morphology of the hepatopancreas and intestine in the freshwater crab Sinopotamon henanense. Crabs were exposed to sublethal Cd concentrations of 0, 0.725, 1.450 and 2.900 mg/L for 21 days. After Cd exposure, the activities of maltase, amylase and trypsin of two tissues were lower than the control. The activities of superoxide dismutase, catalase and glutathione peroxidase in the hepatopancreas and intestine were decreased, and the MDA concentration increased in all of the treated groups, over the experimental period. The results of light and transmission electron microscopy showed that 2.900 mg/L of Cd exposure caused profound morphological damages in the hepatopancreas and midgut. After exposure, histological abnormalities of two tissues were discovered, including cellular swelling and necrosis. Additionally, alterations in microvilli, nucleus, mitochondria, rough endoplasmic reticulum as well as Golgi complex in epithelial cells of two tissues were observed. This may be due to antioxidant enzymes activities that were reduced by Cd in the alimentary system of the crabs, and led to membrane lipid peroxidation. The membrane structure was destroyed, and caused further tissue damage, which likely made the alimentary system unable to secrete digestive enzymes, leading to further reduction of digestive enzymes.
Related JoVE Video
The Sulfolobus initiator element is an important contributor to promoter strength.
J. Bacteriol.
PUBLISHED: 09-13-2013
Show Abstract
Hide Abstract
Basal elements in archaeal promoters, except for putative initiator elements encompassing transcription start sites, are well characterized. Here, we employed the Sulfolobus araS promoter as a model to study the function of the initiator element (Inr) in archaea. We have provided evidence for the presence of a third core promoter element, the Sulfolobus Inr, whose action depends on a TATA box and the TFB recognition element (BRE). Substitution mutations in the araS Inr did not alter the location of the transcription start site. Using systematic mutagenesis, the most functional araS Inr was defined as +1 GAGAMK +6 (where M is A/C and K is G/T). Furthermore, WebLogo analysis of a subset of promoters with coding sequences for 5 untranslated regions (UTRs) larger than 4 nucleotides (nt) in Sulfolobus solfataricus P2 identified an Inr consensus that exactly matches the functional araS Inr sequence. Moreover, mutagenesis of 3 randomly selected promoters confirmed the Inr sequences to be important for basal promoter strength in the subgroup. Importantly, the result of the araS Inr being added to the Inr-less promoters indicates that the araS Inr, the core promoter element, is able to enhance the strength of Inr-less promoters. We infer that transcription factor B (TFB) and subunits of RNA polymerase bind the Inr to enhance promoter strength. Taken together, our data suggest that the presence or absence of an Inr on basal promoters is important for global gene regulation in Sulfolobus.
Related JoVE Video
LCIB in the Chlamydomonas CO2-concentrating mechanism.
Photosyn. Res.
PUBLISHED: 09-01-2013
Show Abstract
Hide Abstract
The CO2-concentrating mechanism confers microalgae a versatile and efficient strategy for adapting to a wide range of environmental CO2 concentrations. LCIB, which has been demonstrated as a key player in the eukaryotic algal CO2-concentrating mechanism (CCM), is a novel protein in Chlamydomonas lacking any recognizable domain or motif, and its exact function in the CCM has not been clearly defined. The unique air-dier growth phenotype and photosynthetic characteristics in the LCIB mutants, and re-localization of LCIB between different subcellular locations in response to different levels of CO2, have indicated that the function of LCIB is closely associated with a distinct low CO2 acclimation state. Here, we review physiological and molecular evidence linking LCIB with inorganic carbon accumulation in the CCM and discuss the proposed function of LCIB in several inorganic carbon uptake/accumulation pathways. Several new molecular characteristics of LCIB also are presented.
Related JoVE Video
Impact of self-assembled monolayer films with specific chemical group on bFGF adsorption and endothelial cell growth on gold surface.
J Biomed Mater Res A
PUBLISHED: 08-22-2013
Show Abstract
Hide Abstract
In this study, thiols ended with methyl, carboxyl, hydroxy, and amino groups are self-assembled on gold surfaces. The X-ray photoelectron spectroscopy test results show that chemical components on the self-assembled surface are similar to those in the theoretical calculations. The atomic force microscope test results show that the molecule assembled on the surface causes no significant variation in the surface roughness before and after the molecule assembly. The water surface contact angle increases with the increasing hydrophilicity of the end groups of the self-assembled monolayer. The surface zeta potential reveals that ?COOH surface has the most electronegativity. The resulting substrates are then made to adsorb base fibroblast growth factor (bFGF). The quartz crystal microbalance test results show that the amounts of bFGF adsorbed onto different self-assembled surfaces are ?COOH??OH>?CH3 >?NH2 . According to cell culture experiments, endothelial cells have different morphologies after adhering to different surfaces. Furthermore, endothelial cells achieve the quickest proliferation on the ?COOH self-assembled surface and the slowest proliferation on the ?CH3 self-assembled surface. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Related JoVE Video
Preclinical characterization of GLS4, an inhibitor of hepatitis B virus core particle assembly.
Antimicrob. Agents Chemother.
PUBLISHED: 08-19-2013
Show Abstract
Hide Abstract
Hepatitis B virus (HBV)-associated chronic liver diseases are treated with nucleoside analogs that target the virus polymerase. While these analogs are potent, drugs are needed to target other virus-encoded gene products to better block the virus replication cycle and chronic liver disease. This work further characterized GLS4 and compared it to the related BAY 41-4109, both of which trigger aberrant HBV core particle assembly, where the virus replication cycle occurs. This was done in HepAD38 cells, which replicate HBV to high levels. In vitro, GLS4 was significantly less toxic for primary human hepatocytes (P < 0.01 up to 100 ?M), inhibited virus accumulation in the supernantant of HepAD38 cells (P < 0.02 up to 100 nM), inhibited HBV replicative forms in the liver with a significantly lower 50% effective concentration (EC50) (P < 0.02), and more strongly inhibited core gene expression (P < 0.001 at 100 to 200 nM) compared to BAY 41-4109. In vivo characterization was performed in nude mice inoculated with HepAD38 cells, which grew out as tumors, resulting in viremia. Treatment of mice with GLS4 and BAY 41-4109 showed strong and sustained suppression of virus DNA to about the same extents both during and after treatment. Both drugs reduced the levels of intracellular core antigen in the tumors. Alanine aminotransferase levels were normal. Tumor and total body weights were not affected by treatment. Thus, GLS4 was as potent as the prototype, BAY 41-4109, and was superior to lamivudine, in that there was little virus relapse after the end of treatment and no indication of toxicity.
Related JoVE Video
HSV-1 activates NF-kappaB in mouse astrocytes and increases TNF-alpha and IL-6 expression via Toll-like receptor 3.
Neurol. Res.
PUBLISHED: 08-17-2013
Show Abstract
Hide Abstract
To investigate the effect of HSV-1 infection via TLR3 on the transcriptional activity of NF-kappaB and the expression of cytokines TNF-alpha and IL-6 in astrocytes.
Related JoVE Video
Sublethal Cd-induced cellular damage and metabolic changes in the freshwater crab Sinopotamon henanense.
Environ Sci Pollut Res Int
PUBLISHED: 08-12-2013
Show Abstract
Hide Abstract
To explore whether sublethal cadmium (Cd) exposure causes branchial cellular damages and affects the metabolic activity in brachyuran crustaceans, the freshwater crab Sinopotamon henanense was exposed to 0.71, 1.43, and 2.86 mg/L Cd(2+) for 3 weeks. Gill morphology, metabolic activity (activities of isocitrate dehydrogenase (IDH), cytochrome c oxidase (CCO) and lactate dehydrogenase (LDH), mRNA expression of CCO active subunit 1 (cco-1) and ldh, as well as ATP levels) in crab muscle were investigated. The results showed that sublethal Cd exposure caused profound morphological damages in the gills. The branchial epithelial cells were disorganized and vacuolized. Ultrastructurally, a decrease in number of apical microvilli, vacuolized mitochondria, and condensed chromatin were observed in gill epithelial cells. Correspondingly, the Cd exposure also induced downregulations of cco-1 and ldh mRNA expression and reduced activities of IDH, CCO, and LDH, in accordance with the lower ATP level in crab muscle. These results led to the conclusion that gill damage caused by sublethal Cd exposure could lead to an impairment of oxygen uptake of S. henanense, and the inhibition of metabolic activity decreases the oxygen demand of the crab and assists them to survive under the condition of lower oxygen availability. These effects add to our understanding on toxic effects of Cd and survival management of S. henanense subchronically exposed to sublethal Cd.
Related JoVE Video
A scoring system to predict the risk of anastomotic leakage after anterior resection for rectal cancer.
J Surg Oncol
PUBLISHED: 08-01-2013
Show Abstract
Hide Abstract
Various risk factors for anastomotic leakage after anterior resection for rectal cancer have been documented in previous studies. However, there have been no quantized studies to more accurately predict the risk of anastomotic leakage.
Related JoVE Video
In vitro investigation on the biodegradability and biocompatibility of genipin cross-linked porcine acellular dermal matrix with intrinsic fluorescence.
ACS Appl Mater Interfaces
PUBLISHED: 07-24-2013
Show Abstract
Hide Abstract
As a biocompatible and bioactive natural tissue engineering scaffold, porcine acellular dermal matrix (PADM) has limitations for the application in tissue regeneration due to its low strength and rapid biodegradation. Here, purified PADM was modified by a nontoxic cross-linker (genipin) to enhance its mechanical properties and improve its resistance to enzymatic degradation. In vitro testing results demonstrated that the stiffness of the genipin cross-linked PADM was improved and biodegradation rate was decreased. Results of cell proliferation assays showed that the cross-linking reaction by genipin did not undermine the cytocompatibility of PADM. Furthermore, genipin cross-linking imparted an observable fluorescence allowing visualization of the scaffolds three-dimensional (3D) porous structure and cell distribution by confocal laser scanning microscopy (CLSM). Immunostaining of the cell nuclei and cytoskeleton indicated that MC3T3-E1 preosteoblasts were tightly adhered to and uniformly distributed onto the cross-linked PADM scaffold. Results of this study suggest that the 3D porous genipin cross-linked PADM with intrinsic fluorescence may have broader applications for tissue engineering scaffolds where higher mechanical stiffness is needed.
Related JoVE Video
Automated tracking of mitotic spindle pole positions shows that LGN is required for spindle rotation but not orientation maintenance.
Cell Cycle
PUBLISHED: 07-16-2013
Show Abstract
Hide Abstract
Spindle orientation defines the plane of cell division and, thereby, the spatial position of all daughter cells. Here, we develop a live cell microscopy-based methodology to extract spindle movements in human epithelial cell lines and study how spindles are brought to a pre-defined orientation. We show that spindles undergo two distinct regimes of movements. Spindles are first actively rotated toward the cells long-axis and then maintained along this pre-defined axis. By quantifying spindle movements in cells depleted of LGN, we show that the first regime of rotational movements requires LGN that recruits cortical dynein. In contrast, the second regime of movements that maintains spindle orientation does not require LGN, but is sensitive to 2ME2 that suppresses microtubule dynamics. Our study sheds first insight into spatially defined spindle movement regimes in human cells, and supports the presence of LGN and dynein independent cortical anchors for astral microtubules.
Related JoVE Video

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

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

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

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