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Find video protocols related to scientific articles indexed in Pubmed.
Lasers: distributed feedback imprinted electrospun fiber lasers (adv. Mater. 38/2014).
Adv. Mater. Weinheim
PUBLISHED: 10-11-2014
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Laser architectures based on nanowires and nanofibers have attracted a continuously increasing interest in the last years. On page 6542, L. Persano, A. Camposeo, S. D'Agostino, D. Pisignano, and co-workers demonstrate imprinted nanopatterned lasers that are realized on the surface of single, electrospun, light-emitting polymer nanofibers. This method leads to individual fiber lasers that exhibit a lasing threshold that is reduced with respect to those from traditional thin-film architectures. Imprinting arbitrary photonic crystal geometries on electrospun lasing nanofibers will open new perspectives in optical circuits and nanophotonics.
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Influences on adherence to diet and physical activity recommendations in women and children: insights from six European studies.
Ann. Nutr. Metab.
PUBLISHED: 10-02-2014
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Across Europe, poor health behaviours are associated with increased risks of non-communicable diseases. There is particular concern about young women, children and families, not least as health behaviours operating before and during pregnancy and in early postnatal life may have profound long-term consequences for children's health. Using findings drawn from 7 European countries, we aimed to identify barriers to the implementation and uptake of dietary and physical activity recommendations, and to consider how best to achieve changes in mothers' behaviours and thereby improve the adoption of health recommendations. Six studies across the 7 countries were used for this narrative synthesis of findings. Key Messages: A woman's education has a strong influence on her own and her children's health behaviours. Women's diets vary across ethnic groups and according to number of children, but psychological factors, such as self-efficacy and sense of control, which may be amenable to modification, are powerful, too, particularly in women with lower educational attainment. Maternal influences on children's behaviours are strong. Differences exist in infant feeding across countries, and there are apparent urban/rural differences in children's diets and physical activity.
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Thrombospondin-1 is part of a Slug-independent motility and metastatic program in cutaneous melanoma, in association with VEGFR-1 and FGF-2.
Pigment Cell Melanoma Res
PUBLISHED: 09-18-2014
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Differently from most transformed cells, cutaneous melanoma expresses the pleiotropic factor thrombospondin-1 (TSP-1). Herein, we show that TSP-1 (RNA and protein), undetectable in four cultures of melanocytes and a RGP melanoma, was variously present in 13 cell lines from advanced melanomas or metastases. Moreover, microarray analysis of 55 human lesions showed higher TSP-1 expression in primary melanomas and metastases than in common and dysplastic nevi. In a functional enrichment analysis, the expression of TSP-1 correlated with motility-related genes. Accordingly, TSP-1 production was associated with melanoma cell motility in vitro and lung colonization potential in vivo. VEGF/VEGFR-1 and FGF-2, involved in melanoma progression, regulated TSP-1 production. These factors were coexpressed with TSP-1 and correlated negatively with Slug (SNAI2), a cell migration master gene implicated in melanoma metastasis. We conclude that TSP-1 cooperates with FGF-2 and VEGF/VEGFR-1 in determining melanoma invasion and metastasis, as part of a Slug-independent motility program.
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Influence of electrotaxis on cell behaviour.
Integr Biol (Camb)
PUBLISHED: 07-25-2014
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Understanding the mechanism of cell migration and interaction with the microenvironment is not only of critical significance to the function and biology of cells, but also has extreme relevance and impact on physiological processes and diseases such as morphogenesis, wound healing, neuron guidance, and cancer metastasis. External guidance factors such as topography and physical cues of the microenvironment promote directional migration and can target specific changes in cell motility and signalling mechanisms. Recent studies have shown that cells can directionally respond to applied electric fields (EFs), in both in vitro and in vivo settings, a phenomenon called electrotaxis. However, the exact cellular mechanisms for sensing electrical signals are still not fully well understood, and it is thus far unknown how cells recognize and respond to electric fields, although some studies have suggested that electro-migration of some cell surface receptors and ion channels in cells could be involved. Applied electric fields may have a potential clinical role in guiding cell migration and present a more precise manageability to change the magnitude and direction of the electric field than most other guidance cues such as chemical cues. Here we present a review of recent studies used for studying electrotaxis to point out similarities, identify points of disagreement, and stimulate new directions for investigation. Insights into the mechanisms by which applied EFs direct cell migration, morphological change and development will enable current and future therapeutic applications to be optimized.
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0068?Occupational exposure to hand-transmitted vibration and risk of Dupuytren's contracture.
Occup Environ Med
PUBLISHED: 07-15-2014
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To assess the relation between Dupuytren's contracture and occupational exposure to hand-transmitted vibration (HTV).
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0066?Problems of vision, hearing and balance and risks of workplace injury.
Occup Environ Med
PUBLISHED: 07-15-2014
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To assess the role of sensory impairments and disorders of balance in occupational injury.
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High expression of the mismatch repair protein MSH6 is associated with poor patient survival in melanoma.
Am. J. Clin. Pathol.
PUBLISHED: 06-14-2014
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The outcome of patients with primary melanoma (PM) cannot be completely explained based on currently adopted clinical-histopathologic criteria. In this study, we evaluated the potential prognostic value of mismatch repair protein expression in PMs.
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Cross-category adaptation: exposure to faces produces gender aftereffects in body perception.
Psychol Res
PUBLISHED: 05-03-2014
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Prolonged exposure to a stimulus results in a subsequent perceptual bias. This perceptual adaptation aftereffect occurs not only for simple stimulus features but also for high-level stimulus properties (e.g., faces' gender, identity and emotional expressions). Recent studies on aftereffects demonstrate that adaptation to human bodies can modulate face perception because these stimuli share common properties. Those findings suggest that the aftereffect is not related to the physical property of the stimulus but to the great number of semantic attributes shared by the adapter and the test. Here, we report a novel cross-category adaptation paradigm with both silhouette face profiles (Experiment 1.1) and frontal view faces (Experiment 2) as adapters, testing the aftereffects when viewing an androgynous test body. The results indicate that adaptation to both silhouette face profiles and frontal view faces produces gender aftereffects (e.g., after visual exposure to a female face, the androgynous body appears as more male and vice versa). These findings confirm that high-level perceptual aftereffects can occur between cross-categorical stimuli that share common properties.
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Distributed feedback imprinted electrospun fiber lasers.
Adv. Mater. Weinheim
PUBLISHED: 04-30-2014
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Imprinted, distributed feedback lasers are demonstrated on individual, active electrospun polymer nanofibers. In addition to advantages related to miniaturization, optical confinement and grating nanopatterning lead to a significant threshold reduction compared to conventional thin-film lasers. The possibility of imprinting arbitrary photonic crystal geometries on electrospun lasing nanofibers opens new opportunities for realizing optical circuits and chips.
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Cilengitide down-modulates invasiveness and vasculogenic mimicry of neuropilin-1 expressing melanoma cells through the inhibition of ?v?5 integrin.
Int. J. Cancer
PUBLISHED: 03-21-2014
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During melanoma progression, tumour cells show increased adhesiveness to the vascular wall, invade the extracellular matrix (ECM) and frequently form functional channels similar to vascular vessels (vasculogenic mimicry). These properties are mainly mediated by the interaction of integrins with ECM components. Since we had previously identified neuropilin-1 (NRP-1), a co-receptor of vascular endothelial growth factor A (VEGF-A), as an important determinant of melanoma aggressiveness, aims of this study were to identify the specific integrins involved in the highly invasive phenotype of NRP-1 expressing cells and to investigate their role as targets to counteract melanoma progression. Melanoma aggressiveness was evaluated in vitro as cell ability to migrate through an ECM layer and to form tubule-like structures using transfected cells. Integrins relevant to these processes were identified using specific blocking antibodies. The ?v?5 integrin was found to be responsible for about 80% of the capability of NRP-1 expressing cells to adhere on vitronectin. In these cells ?v?5 expression level was twice higher than in low-invasive control cells and contributed to the ability of melanoma cells to form tubule-like structures on matrigel. Cilengitide, a potent inhibitor of ?? integrins activation, reduced ECM invasion, vasculogenic mimicry and VEGF-A and metalloproteinase-9 (MMP-9) secretion by melanoma cells. In conclusion, we demonstrated that ???5 integrin is involved in the highly aggressive phenotype of melanoma cells expressing NRP-1. Moreover, we identified a novel mechanism that contributes to the anti-melanoma activity of the ?v integrin inhibitor cilengitide based on the inhibition of vasculogenic mimicry. © 2014 Wiley Periodicals, Inc.
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The role of mental health problems and common psychotropic drug treatments in accidental injury at work: a case-control study.
Occup Environ Med
PUBLISHED: 03-13-2014
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Mental illness and psychotropic drugs have been linked with workplace injury, but few studies have measured exposures and outcomes independently or established their relative timings. To address this shortcoming, we conducted a case-control study nested within a database prospectively recording injury consultations, diagnoses and drug prescriptions.
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Dupuytren's contracture and occupational exposure to hand-transmitted vibration.
Occup Environ Med
PUBLISHED: 01-21-2014
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The relation between Dupuytren's contracture and occupational exposure to hand-transmitted vibration (HTV) has frequently been debated. We explored associations in a representative national sample of workers with well-characterised exposure to HTV.
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Scrutinizing visual images: the role of gaze in mental imagery and memory.
Cognition
PUBLISHED: 01-13-2014
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Gaze was monitored by use of an infrared remote eye-tracker during perception and imagery of geometric forms and figures of animals. Based on the idea that gaze prioritizes locations where features with high information content are visible, we hypothesized that eye fixations should focus on regions that contain one or more local features that are relevant for object recognition. Most importantly, we predicted that when observers looked at an empty screen and at the same time generated a detailed visual image of what they had previously seen, their gaze would probabilistically dwell within regions corresponding to the original positions of salient features or parts. Correlation analyses showed positive relations between gaze's dwell time within locations visited during perception and those in which gaze dwelled during the imagery generation task. Moreover, the more faithful an observer's gaze enactment, the more accurate was the observer's memory, in a separate test, of the dimension or size in which the forms had been perceived. In another experiment, observers saw a series of pictures of animals and were requested to memorize them. They were then asked later, in a recall phase, to answer a question about a property of one of the encoded forms; it was found that, when retrieving from long-term memory a previously seen picture, gaze returned to the location of the part probed by the question. In another experimental condition, the observers were asked to maintain fixation away from the original location of the shape while thinking about the answer, so as to interfere with the gaze enactment process; such a manipulation resulted in measurable costs in the quality of memory. We conclude that the generation of mental images relies upon a process of enactment of gaze that can be beneficial to visual memory.
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Imagining sex and adapting to it: different aftereffects after perceiving versus imagining faces.
Vision Res.
PUBLISHED: 01-03-2014
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A prolonged exposure (i.e., perceptual adaptation) to a male or a female face can produce changes (i.e., aftereffects) in the subsequent gender attribution of a neutral or average face, so that it appears respectively more female or more male. Studies using imagery adaptation and its aftereffects have yielded conflicting results. In the present study we used an adaptation paradigm with both imagined and perceived faces as adaptors, and assessed the aftereffects in judged masculinity/femininity when viewing an androgynous test face. We monitored eye movements and pupillary responses as a way to confirm whether participants did actively engage in visual imagery. The results indicated that both perceptual and imagery adaptation produce aftereffects, but that they run in opposite directions: a contrast effect with perception (e.g., after visual exposure to a female face, the androgynous appears as more male) and an assimilation effect with imagery (e.g., after imaginative exposure to a female face, the androgynous face appears as more female). The pupillary responses revealed dilations consistent with increased cognitive effort during the imagery phase, suggesting that the assimilation aftereffect occurred in the presence of an active and effortful mental imagery process, as also witnessed by the pattern of eye movements recorded during the imagery adaptation phase.
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Hydroxytyrosol prevents increase of osteoarthritis markers in human chondrocytes treated with hydrogen peroxide or growth-related oncogene ?.
PLoS ONE
PUBLISHED: 01-01-2014
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Hydroxytyrosol (HT), a phenolic compound mainly derived from olives, has been proposed as a nutraceutical useful in prevention or treatment of degenerative diseases. In the present study we have evaluated the ability of HT to counteract the appearance of osteoarthritis (OA) features in human chondrocytes. Pre-treatment of monolayer cultures of chondrocytes with HT was effective in preventing accumulation of reactive oxidant species (ROS), DNA damage and cell death induced by H2O2 exposure, as well as the increase in the mRNA level of pro-inflammatory, matrix-degrading and hypertrophy marker genes, such as iNOS, COX-2, MMP-13, RUNX-2 and VEGF. HT alone slightly enhanced ROS production, but did not enhance cell damage and death or the expression of OA-related genes. Moreover HT was tested in an in vitro model of OA, i.e. three-dimensional micromass cultures of chondrocytes stimulated with growth-related oncogene ? (GRO?), a chemokine involved in OA pathogenesis and known to promote hypertrophy and terminal differentiation of chondrocytes. In micromass constructs, HT pre-treatment inhibited the increases in caspase activity and the level of the messengers for iNOS, COX-2, MMP-13, RUNX-2 and VEGF elicited by GRO?. In addition, HT significantly increased the level of SIRT-1 mRNA in the presence of GRO?. In conclusion, the present study shows that HT reduces oxidative stress and damage, exerts pro-survival and anti-apoptotic actions and favourably influences the expression of critical OA-related genes in human chondrocytes treated with stressors promoting OA-like features.
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Effects of immigrant status on emergency room (ER) utilisation by children under age one: a population-based study in the province of Reggio Emilia (Italy).
BMC Health Serv Res
PUBLISHED: 10-28-2013
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The primary aim of this study was to assess the effect of immigrant status on Emergency Room (ER) utilisation by children under age one, considering all, non-urgent, very urgent, and followed by hospitalisation visits. The second aim was to investigate the role played by mothers educational level in the relationship between citizenship and ER utilisation.
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Pediatrician-led motivational interviewing to treat overweight children: an RCT.
Pediatrics
PUBLISHED: 10-21-2013
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The aim of this study was to evaluate the effect of family pediatrician-led motivational interviews (MIs) on BMI of overweight (85th ? BMI percentile ? 95 th) children aged 4 to 7 years.
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Notch3 inhibition enhances sorafenib cytotoxic efficacy by promoting GSK3b phosphorylation and p21 down-regulation in hepatocellular carcinoma.
Oncotarget
PUBLISHED: 10-12-2013
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Sorafenib (Nexavar), a multiple kinase inhibitor, is the only clinically approved drug for patients with advanced HCC. However, its therapeutic success is limited by the emergence of drug resistance. Here we found that p21 and pGSK3?Ser9 are major players in the resistance to sorafenib. We recently reported that aberrant Notch3 expression in HCC contributes to doxorubicin resistance in vitro and, therefore, we focused on the mechanisms that associate Notch3 to acquired drug resistance. In this study we first found that Notch3 inhibition significantly increased the apoptosis inducing effect of sorafenib in HCC cells via specific down-regulation of p21 and up-regulation of pGSK3?Ser9. Using a mouse xenograft model we further found that Notch3 depletion combined with 21 days of sorafenib treatment exerts a substantial antitumor effect in vivo. Interestingly, we showed that, upon exposure to sorafenib treatment, Notch3 depleted xenografts maintain lower levels of p21 and higher levels of pGSK3?Ser9 than control xenografts. Thus, this study demonstrated that inhibition of Notch3 signaling prevents HCC-mediate drug resistance and sensitizes HCC cells to sorafenib. Finally, we validated our in vitro and in vivo results in primary human HCCs showing that Notch3 protein expression positively correlated with p21 protein expression and negatively correlated with pGSK3?Ser9 expression. In conclusion, the results presented in this study demonstrated that Notch3 silencing enhances the effect of sorafenib by overcoming drug resistance. Notch3 inhibition in combination with sorafenib can be a promising strategy for treatment of HCC.
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Conscious and unconscious processing of facial expressions: Evidence from two split-brain patients.
J Neuropsychol
PUBLISHED: 07-30-2013
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We investigated how the brains hemispheres process explicit and implicit facial expressions in two split-brain patients (one with a complete and one with a partial anterior resection). Photographs of faces expressing positive, negative or neutral emotions were shown either centrally or bilaterally. The task consisted in judging the friendliness of each person in the photographs. Half of the photograph stimuli were hybrid faces, that is an amalgamation of filtered images which contained emotional information only in the low range of spatial frequency, blended to a neutral expression of the same individual in the rest of the spatial frequencies. The other half of the images contained unfiltered faces. With the hybrid faces the patients and a matched control group were more influenced in their social judgements by the emotional expression of the face shown in the left visual field (LVF). When the expressions were shown explicitly, that is without filtering, the control group and the partially callosotomized patient based their judgement on the face shown in the LVF, whereas the complete split-brain patient based his ratings mainly on the face presented in the right visual field. We conclude that the processing of implicit emotions does not require the integrity of callosal fibres and can take place within subcortical routes lateralized in the right hemisphere.
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Metallic-like stoichiometric copper sulfide nanocrystals: phase- and shape-selective synthesis, near-infrared surface plasmon resonance properties, and their modeling.
ACS Nano
PUBLISHED: 07-23-2013
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In the realm of semiconductor nanomaterials, a crystal lattice heavily doped with cation/anion vacancies or ionized atomic impurities is considered to be a general prerequisite to accommodating excess free carriers that can support localized surface plasmon resonance (LSPR). Here, we demonstrate a surfactant-assisted nonaqueous route to anisotropic copper sulfide nanocrystals, selectively trapped in the covellite phase, which can exhibit intense, size-tunable LSPR at near-infrared wavelengths despite their stoichiometric, undoped structure. Experimental extinction spectra are satisfactorily reproduced by theoretical calculations performed by the discrete dipole approximation method within the framework of the Drude-Sommerfeld model. The LSPR response of the nanocrystals and its geometry dependence are interpreted as arising from the inherent metallic-like character of covellite, allowed by a significant density of lattice-constitutional valence-band free holes. As a consequence of the unique electronic properties of the nanocrystals and of their monodispersity, coherent excitation of symmetric radial breathing modes is observed for the first time in transient absorption experiments at LSPR wavelengths.
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Non-activated protein C rescue treatment in Wilms tumour associated hepatic sinusoidal obstructive syndrome.
Pediatr Blood Cancer
PUBLISHED: 06-18-2013
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Hepatic sinusoidal obstructive syndrome (HSOS) is a frequent complication in patients undergoing haematopoietic stem cell transplant (HSCT), and more rarely, in paediatric patients receiving conventional chemotherapy for solid tumours. Its diagnosis relies on a combination of clinical signs and symptoms such as hepatomegaly, jaundice, weight gain and fluid retention. HSOS treatment is primarily based on supportive care and anti-fibrinolytic agents. Here we report two patients affected by Wilms tumour who developed life-threatening HSOS that failed to respond to conventional treatment. Both patients recovered after receiving aggressive supportive treatment that included administration of non-activated protein C (Ceprotin®-Baxter). Pediatr Blood Cancer © 2013 Wiley Periodicals, Inc.
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Polyamine delivery as a tool to modulate stem cell differentiation in skeletal tissue engineering.
Amino Acids
PUBLISHED: 05-04-2013
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The first step in skeleton development is the condensation of mesenchymal precursors followed by any of two different types of ossification, depending on the type of bone segment: in intramembranous ossification, the bone is deposed directly in the mesenchymal anlagen, whereas in endochondral ossification, the bone is deposed onto a template of cartilage that is subsequently substituted by bone. Polyamines and polyamine-related enzymes have been implicated in bone development as global regulators of the transcriptional and translational activity of stem cells and pivotal transcription factors. Therefore, it is tempting to investigate their use as a tool to improve regenerative medicine strategies in orthopedics. Growing evidence in vitro suggests a role for polyamines in enhancing differentiation in both adult stem cells and differentiated chondrocytes. Adipose-derived stem cells have recently proved to be a convenient alternative to bone marrow stromal cells, due to their easy accessibility and the high frequency of stem cell precursors per volume unit. State-of-the-art "prolotherapy" approaches for skeleton regeneration include the use of adipose-derived stem cells and platelet concentrates, such as platelet-rich plasma (PRP). Besides several growth factors, PRP also contains polyamines in the micromolar range, which may also exert an anti-apoptotic effect, thus helping to explain the efficacy of PRP in enhancing osteogenesis in vitro and in vivo. On the other hand, spermidine and spermine are both able to enhance hypertrophy and terminal differentiation of chondrocytes and therefore appear to be inducers of endochondral ossification. Finally, the peculiar activity of spermidine as an inducer of autophagy suggests the possibility of exploiting its use to enhance this cytoprotective mechanism to counteract the degenerative changes underlying either the aging or degenerative diseases that affect bone or cartilage.
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Accumulation of altered aspartyl residues in erythrocyte membrane proteins from patients with sporadic amyotrophic lateral sclerosis.
Neurochem. Int.
PUBLISHED: 04-23-2013
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Spontaneous protein deamidation of labile asparagines (Asn), generating abnormal l-isoaspartyl residues (IsoAsp), is associated with cell aging and enhanced by an oxidative microenvironment. The presence of isopeptide bonds impairs protein structure/function. To minimize the damage, IsoAsp can be "repaired" by the protein l-isoaspartyl/d-aspartyl O-methyltransferase (PIMT) and S-adenosylmethionine (AdoMet) is the methyl donor of this reaction. PIMT is a repair enzyme that initiates the conversion of l-isoAsp (or d-Asp) residues to l-Asp residues. Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease principally affecting motor neurons. The condition of oxidative stress reported in familial and sporadic forms of ALS prompted us to investigate Asn deamidation in ALS tissue. Erythrocytes (RBCs) were selected as a model system since they are unable to replace damaged proteins and protein methylesterification is virtually the only AdoMet-consuming reaction operating in these cells. Our data show that, in vitro assay, abnormal IsoAsp residues were significantly higher in ALS patients erythrocyte membrane proteins with an increased methyl accepting capability relative to controls (p<0.05). Moreover, we observed a reduction in AdoMet levels, while AdoHcy concentration was comparable to that detected in the control, resulting in a lower [AdoMet]/[AdoHcy] ratio. Then, the accumulation of altered aspartyl residues in ALS patients is probably related to a reduced efficiency of the S-adenosylmethionine (AdoMet)-dependent repair system causing increased protein instability at Asn sites. The increase of abnormal residues represents a new protein alteration that may be present not only in red blood cells but also in other cell types of patients suffering from ALS.
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XPF protein levels determine sensitivity of malignant melanoma cells to oxaliplatin chemotherapy: Suitability as a biomarker for patient selection.
Int. J. Cancer
PUBLISHED: 03-25-2013
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As the options for systemic treatment of malignant melanoma (MM) increase, the need to develop biomarkers to identify patients who might benefit from cytotoxic chemotherapy becomes more apparent. In preclinical models, oxaliplatin has activity in cisplatin-resistant cells. In this study, we have shown that oxaliplatin forms interstrand crosslinks (ICLs) in cellular DNA and that loss of the heterodimeric structure-specific endonuclease XPF-ERCC1 causes hypersensitivity to oxaliplatin in mammalian cells. XPF deficiency resulted in late S-phase arrest and persistence of double-strand breaks following oxaliplatin treatment. In a panel of 12 MM cell lines, oxaliplatin sensitivity correlated with XPF and ERCC1 protein levels. The knockdown of ERCC1 and XPF protein levels by RNA interference increased sensitivity of cancer cells to oxaliplatin; overexpression of exogenous ERCC1 significantly decreased drug sensitivity. Following immunohistochemical optimization, XPF protein levels were quantified in MM tissue samples from 183 patients, showing variation in expression and no correlation with prognosis. In 57 patients with MM treated with cisplatin or carboplatin, XPF protein levels did not predict the likelihood of clinical response. We propose that oxaliplatin should not be discarded as a potential treatment for MM on the basis of the limited activity of cisplatin in unselected patients. Moreover, we show that XPF-ERCC1 protein levels are a key determinant of the sensitivity of melanoma cells to oxaliplatin in vitro. Immunohistochemical detection of XPF appears suitable for development as a tissue biomarker for potentially selecting patients for oxaliplatin treatment in a prospective clinical trial.
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Platelet-derived growth factor C and calpain-3 are modulators of human melanoma cell invasiveness.
Oncol. Rep.
PUBLISHED: 02-11-2013
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The molecular mechanisms responsible for the elevated metastatic potential of malignant melanoma are still not fully understood. In order to shed light on the molecules involved in the acquisition by melanoma of a highly aggressive phenotype, we compared the gene expression profiles of two cell clones derived from the human cutaneous metastatic melanoma cell line M14: a highly invasive clone (M14C2/MK18) and a clone (M14C2/C4) with low ability to invade the extracellular matrix (ECM). The highly invasive phenotype of M14C2/MK18 cells was correlated with overexpression of neuropilin-1, activation of a vascular endothelial growth factor (VEGF)-A/VEGFR-2 autocrine loop and secretion of matrix metalloprotease-2. Moreover, in an in vivo murine model, M14C2/MK18 cells displayed a higher growth rate as compared with M14C2/C4 cells, even though in vitro both clones possessed comparable proliferative potential. Microarray analysis in M14C2/MK18 cells showed a strong upregulation of platelet-derived growth factor (PDGF)-C, a cytokine that contributes to angiogenesis, and downregulation of calpain-3, a calcium-dependent thiol-protease that regulates specific signalling cascade components. Inhibition of PDGF-C with a specific antibody resulted in a significant decrease in ECM invasion by M14C2/MK18 cells, confirming the involvement of PDGF-C in melanoma cell invasiveness. Moreover, the PDGF-C transcript was found to be upregulated in a high percentage of human melanoma cell lines (17/20), whereas only low PDGF-C levels were detected in a few melanocytic cultures (2/6). By contrast, inhibition of calpain-3 activity in M14C2/C4 control cells, using a specific chemical inhibitor, markedly increased ECM invasion, strongly suggesting that downregulation of calpain-3 plays a role in the acquisition of a highly invasive phenotype. The results indicate that PDGF-C upregulation and calpain-3 downregulation are involved in the aggressiveness of malignant melanoma and suggest that modulators of these proteins or their downstream effectors may synergise with VEGF?A therapies in combating tumour-associated angiogenesis and melanoma spread.
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Neuropilin-1 expression promotes invasiveness of melanoma cells through vascular endothelial growth factor receptor-2-dependent and -independent mechanisms.
Int. J. Oncol.
PUBLISHED: 01-28-2013
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The majority of human melanoma cell lines secretes vascular endothelial growth factor-A (VEGF-A) and expresses its receptors VEGFR-1, VEGFR-2 and neuropilin-1 (NRP?1), a co-receptor for VEGF-A that amplifies the signalling through VEGFR-2. Since it is known that the VEGF-A/VEGFR-2 autocrine loop promotes melanoma cell invasiveness, the aim of the present study was to investigate the involvement of NPR-1 in melanoma progression. Syngeneic human melanoma cell lines expressing either VEGFR-2 or NRP-1, both or none of them, were analyzed for their in vitro ability to migrate, invade the extracellular matrix (ECM) and secrete active metalloproteinase-2 (MMP-2). The results indicate that NRP-1 cooperates with VEGFR-2 in melanoma cell migration induced by VEGF-A. Moreover, NRP-1 expression is sufficient to promote MMP-2 secretion and melanoma cell invasiveness, as demonstrated by the ability of cells expressing solely NRP-1 to spontaneously invade the ECM. This ability is specifically downregulated by anti-NRP-1 antibodies or by interfering with NRP-1 expression using an shRNA construct. Investigation of the signal transduction pathways triggered by NRP-1 in melanoma cells, indicated that NRP-1-dependent promotion of cell invasiveness involves Akt activation through its phosphorylation on T308. Overall, the results demonstrate that NRP-1 is involved in melanoma progression through VEGFR-2-dependent and -independent mechanisms and suggest NRP-1 as a target for the treatment of the metastatic disease.
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Focusing Narrowly or Broadly Attention When Judging Categorical and Coordinate Spatial Relations: A MEG Study.
PLoS ONE
PUBLISHED: 01-01-2013
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We measured activity in the dorsal system of the human cortex with magnetoencephalography (MEG) during a matching-to-sample plus cueing paradigm, where participants judged the occurrence of changes in either categorical or coordinate spatial relations (e.g., exchanges of left versus right positions or changes in the relative distances) between images of pairs of animals. The attention window was primed in each trial to be either small or large by using cues that immediately preceded the matching image. In this manner, we could assess the modulatory effects of the scope of attention on the activity of the dorsal system of the human cortex during spatial relations processing. The MEG measurements revealed that large spatial cues yielded greater activations and longer peak latencies in the right inferior parietal lobe for coordinate trials, whereas small cues yielded greater activations and longer peak latencies in the left inferior parietal lobe for categorical trials. The activity in the superior parietal lobe, middle frontal gyrus, and visual cortex, was also modulated by the size of the spatial cues and by the type of spatial relation change. The present results support the theory that the lateralization of each kind of spatial processing hinges on differences in the sizes of regions of space attended to by the two hemispheres. In addition, the present findings are inconsistent with the idea of a right-hemispheric dominance for all kinds of challenging spatial tasks, since response times and accuracy rates showed that the categorical spatial relation task was more difficult than the coordinate task and the cortical activations were overall greater in the left hemisphere than in the right hemisphere.
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[Emergency room services utilization in the province of Reggio Emilia: a comparison between immigrants and Italians].
Epidemiol Prev
PUBLISHED: 12-15-2011
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The aim of the study is to compare Italian and immigrant accesses to Emergency Room (ER) Services in the province of Reggio Emilia, with particular attention to time differences and to potentially inappropriate accesses. Setting and participants: the database of ER accesses in the province of Reggio Emilia was analyzed for the years 2007- 2010. In the analysis of the resident population all autochthonous citizens and all immigrants from Developed Countries were considered Italians, while citizens from Developing Countries were Immigrants. Temporary Immigrants were those immigrants with residence and citizenship in a Developing Country.
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Cell self-patterning on uniform PDMS-surfaces with controlled mechanical cues.
Integr Biol (Camb)
PUBLISHED: 12-07-2011
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The exploitation of cell-instructive scaffolds with uniform physical/chemical surfaces and controlled stiffness will be greatly useful in tissue engineering applications to resemble the extracellular matrix (ECM) or topographical appearance of native tissues. We herein describe a versatile and straightforward method to assemble a polydimethylsiloxane (PDMS)-composite structure in which a uniformly laminin-coated membrane is placed on top of a micropatterned substrate that applies a stiffness gradient. This double-sheet structure provides soft or stiff microdomains that guide the self-patterning of different cell types [e.g. chronic myeloid leukemia (KU812), cervix carcinoma (HeLa), NIH 3T3 and BJ], thereby stimulating their cytoskeletal remodeling. More interestingly, we used these uniform PDMS surfaces with patterned rigidity for obtaining co-cultures of tumor blood cells (KU812) and adherent fibroblasts (NIH 3T3) with spatially-controlled distribution. Thus, beyond single-cell stiffening and mechanosensing, these surfaces should also be used as simple and feasible co-culture systems for mimicking and dissecting the bidirectional interactions between blood cells and specific stromal elements of their in vivo microenvironment.
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Placenta growth factor induces melanoma resistance to temozolomide through a mechanism that involves the activation of the transcription factor NF-?B.
Int. J. Oncol.
PUBLISHED: 05-25-2011
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Placenta growth factor (PlGF) and its receptor vascular endothelial growth factor receptor-1 (VEGFR-1) are co-expressed in a large number of human melanoma cell lines. Moreover, a correlation between in vivo PlGF production and melanoma progression has been suggested. To investigate whether PlGF might have a role in protecting melanoma cells from the cytotoxic effects of the anticancer agent temozolomide (TMZ), which is used for the treatment of this malignancy, we stably transfected a doxycycline-inducible PlGF antisense mRNA into a human melanoma cell clone that secretes VEGF-A and PlGF and expresses receptors for both growth factors. Induction of PlGF antisense mRNA in the transfected cells (13443/ASP3 subclone) halved TMZ IC(50), and exogenous addition of PlGF to the culture medium 24 h before TMZ treatment, partially restored IC(50) values to that of control cells. The increased sensitivity of 13443/ASP3 cells upon PlGF antisense mRNA expression was not due to down-regulation of O6-methylguanine-DNA methyltransferase, a DNA repair protein that represents the main mechanism of resistance to TMZ. Since the activity of the transcription factor nuclear factor-?B (NF-?B) has been correlated to melanoma chemoresistance, we investigated whether NF-?B was involved in PlGF-induced melanoma cell resistance to TMZ. Induction of PlGF antisense mRNA in 13443/ASP3 cells halved the levels of active NF-?B and the specific inhibition of this transcription factor increased sensitivity of 13443/ASP3 cells to TMZ. In conclusion, our data strongly suggest that PlGF plays a role in melanoma cell resistance to TMZ through a pathway that involves NF-?B activation.
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MicroRNA-155 targets the SKI gene in human melanoma cell lines.
Pigment Cell Melanoma Res
PUBLISHED: 05-05-2011
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The SKI protein is a transcriptional coregulator over-expressed in melanoma. Experimentally induced down-regulation of SKI inhibits melanoma cell growth in vitro and in vivo. MicroRNAs (miRNAs) negatively modulate gene expression and have been implicated in oncogenesis. We previously showed that microRNA-155 (miR-155) is down-regulated in melanoma cells as compared with normal melanocytes and that its ectopic expression impairs proliferation and induces apoptosis. Here, we investigated whether miR-155 could mediate melanoma growth inhibition via SKI gene silencing. Luciferase reporter assays demonstrated that miR-155 interacted with SKI 3UTR and impaired gene expression. Transfection of melanoma cells with miR-155 reduced SKI levels, while inhibition of endogenous miR-155 up-regulated SKI expression. Specifically designed small interfering RNAs reduced SKI expression and inhibited proliferation. However, melanoma cells over-expressing a 3UTR-deleted SKI were still susceptible to the antiproliferative effect of miR-155. Our data demonstrate for the first time that SKI is a target of miR-155 in melanoma. However, impairment of SKI expression is not the leading mechanism involved in the growth-suppressive effect of miR-155 found in this malignancy.
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Cell Uptake and Validation of Novel PECs for Biomedical Applications.
J Drug Deliv
PUBLISHED: 04-08-2011
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This pilot study provides the proof of principle for biomedical application of novel polyelectrolyte complexes (PECs) obtained via electrostatic interactions between dextran sulphate (DXS) and poly(allylamine hydrochloride) (PAH). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed that DXS/PAH polyelectrolyte complexes were Monodispersed with regular rounded-shape features and average diameters of 250?nm at 2?:?1 weight ratios of DXS/PAH. Fluorescently labelled DXS and fluorescein-isothiocyanate- (FITC-)conjugate DXS were used to follow cell uptake efficiency of PECs and biodegradability of their enzymatically degradable DXS-layers by using confocal laser scanning microscopy (CLSM). Moreover, quantitative MTT and Trypan Blue assays were employed to validate PECs as feasible and safe nanoscaled carriers at single-cell level without adverse effects on metabolism and viability.
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Polymorphisms of GSTM1 and GSTT1, sun exposure and the risk of melanoma: a case-control study.
Acta Derm. Venereol.
PUBLISHED: 04-05-2011
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Glutathione S-transferases (GSTs) are a family of enzymes that are known to play an important role in cellular protection against oxidative stress, including the oxidative stress caused by ultraviolet radiation. This study focused on the possible involvement of GSTM1 and GSTT1 polymorphisms in risk modulation of cutaneous melanoma. Within a case-control study, the presence of the null polymorphism at GSTM1 and GSTT1 was investigated in 188 cases of cutaneous melanoma and 152 controls. Information on socio-demographic characteristics, medical history, sun exposure and pigmentary characteristics were collected for all subjects. Logistic regression was used to estimate odds ratio (OR) and 95% confidence intervals (CI). An interaction was suggested between the GSTM1 and GSTT1 "null" genotype and episodes of sunburn in childhood OR of interaction (1.65, 95% CI (95% CI) 0.27-9.94). The risk of melanoma among the subset of participants who reported sunburns in childhood and who had both null variants, was nine (OR 9.16; 95% CI 1.18-70.9). The results suggest that subjects carrying both GSTM1 and GSTT1 null polymorphisms and experiencing sunburns in childhood have an extremely high risk of melanoma.
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Exogenous control of the expression of Group I CD1 molecules competent for presentation of microbial nonpeptide antigens to human T lymphocytes.
Clin. Dev. Immunol.
PUBLISHED: 01-12-2011
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Group I CD1 (CD1a, CD1b, and CD1c) glycoproteins expressed on immature and mature dendritic cells present nonpeptide antigens (i.e., lipid or glycolipid molecules mainly of microbial origin) to T cells. Cytotoxic CD1-restricted T lymphocytes recognizing mycobacterial lipid antigens were found in tuberculosis patients. However, thanks to a complex interplay between mycobacteria and CD1 system, M. tuberculosis possesses a successful tactic based, at least in part, on CD1 downregulation to evade CD1-dependent immunity. On the ground of these findings, it is reasonable to hypothesize that modulation of CD1 protein expression by chemical, biological, or infectious agents could influence hosts immune reactivity against M. tuberculosis-associated lipids, possibly affecting antitubercular resistance. This scenario prompted us to perform a detailed analysis of the literature concerning the effect of external agents on Group I CD1 expression in order to obtain valuable information on the possible strategies to be adopted for driving properly CD1-dependent immune functions in human pathology and in particular, in human tuberculosis.
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Acetyl-l-Carnitine in the treatment of anhedonia, melancholic and negative symptoms in alcohol dependent subjects.
Prog. Neuropsychopharmacol. Biol. Psychiatry
PUBLISHED: 01-12-2011
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Aim of this randomized, double-blind, placebo-controlled study was to evaluate the efficacy of Acetyl-l-Carnitine (ALC), at different dosages, on specific anhedonic symptoms in detoxified alcohol dependent subjects. Secondary endpoints were the effect of ALC on melancholic and negative symptoms.
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Detection of circulating tumor cells is improved by drug-induced antigen up-regulation: preclinical and clinical studies.
Anticancer Res.
PUBLISHED: 12-01-2010
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(51)Cr-prelabelled colon cancer cells (simulating circulating tumor cells, CTCs) were added to human peripheral blood and exposed to staurosporine (ST) to increase carcinoembryonic antigen (CEA) expression. CTCs were captured with immunomagnetic beads coated with Ber-EP4 monoclonal antibody, recognizing the common epithelial antigen present in the majority of cancer cells of epithelial origin, with capture efficiency of more than 80%. Moreover, ST treatment increased CEA expression without compromising Ber-EP4 capture efficiency. In a pilot clinical study on 37 patients, CTCs were captured using Ber-EP4 beads, and recognized by RT-PCR set for CEA or cytokeratin-19 (CK) mRNA detection. The results showed that: (a) the percentage of CEA-positive CTCs (CTC(CEA), 54.1%) was lower than that of CK-positive CTCs (CTC(CK), 70.3%); (b) in vitro ST treatment converted a significant number of CTC(CEA)-negative into CTC(CEA)-positive cases. Therefore, immunomagnetic capture combined with exposure to ST provides a feasible and sensitive technique for the detection of functionally-active CTCs responsive to ST-mediated CEA up-regulation.
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Lysogenic transfer of mef(A) and tet(O) genes carried by Phim46.1 among group A streptococci.
Antimicrob. Agents Chemother.
PUBLISHED: 07-19-2010
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We report the ex vivo lysogenic transfer of erythromycin and tetracycline resistance genes among group A streptococci (GAS). Of 42 susceptible strains, 69% acquired erythromycin/tetracycline resistance when infected with purified supernatants from strain m46 culture containing the phage ?m46.1. A significant emm-type-dependent barrier to lysogenic transfer was not observed. The emm12 strains were the only strains susceptible to the lytic action of the bacteriophage preparation.
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Acetyl-L-carnitine for alcohol craving and relapse prevention in anhedonic alcoholics: a randomized, double-blind, placebo-controlled pilot trial.
Alcohol Alcohol.
PUBLISHED: 06-30-2010
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The study aimed to evaluate the efficacy of acetyl-l-carnitine (ALC), at different doses, in relapse prevention and craving in anhedonic detoxified alcohol-dependent subjects.
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Active role of oxide layers on the polarization of plasmonic nanostructures.
ACS Nano
PUBLISHED: 06-12-2010
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In this paper a theoretical study of polarization properties of a silver nanosphere touching a homogeneous silver substrate and covered by oxide layers of increasing thickness, is reported. Oxide layers are often deposited on metallic nanostructures in metal-enhanced fluorescence (MEF) or surface-enhanced raman scattering experiments to avoid nonradiative energy transfer from emitters to the metal, and to increase the nanoparticles stability against thermal processes and laser exposure. Not much has been said on the effect of the oxide on the field enhancement of such kind of plasmonic systems. This work aims at filling this gap by shedding light on the effects of the oxide coverage on the near and far field behavior: numerical simulations performed in the framework of the discrete dipole approximation show the presence of new resonances in the absorption spectra and, of major importance for MEF applications, a strong enhancement of the near field around the nanosphere.
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Alexithymia in personality disorders: correlations with symptoms and interpersonal functioning.
Psychiatry Res
PUBLISHED: 05-31-2010
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Impairment in the ability to recognize and make sense of emotions has been hypothesized to be present in a sub-sample of people suffering from personality disorder (PD). In particular it is possible that difficulty recognizing and expressing feelings, or alexithymia, is related to many of the symptoms and problems in making sense of social interactions which are hallmarks of PD. In this study we measured levels of alexithymia with the Toronto Alexithymia Scale-20 and explored its correlations with the overall presence of PD and different PD diagnoses, symptoms, and interpersonal difficulties. Results were largely consistent with the hypothesis. Higher levels of alexithymia were related to high levels of global psychopathology and with dysfunctional representation of interpersonal relations. A sub-sample of patients, mostly suffering from avoidant, dependent, passive-aggressive and depressive PD, had alexithymic features and, in particular reported difficulties describing their feelings to others. A patient with cluster B PD featured no alexithymia. Implications of this study for future research and treatment are discussed.
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Pure white hybrid light-emitting device with color rendering index higher than 90.
Opt Lett
PUBLISHED: 03-03-2010
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The realization of white-light sources with a combination of high color rendering index (CRI), which is the average of the first eight rendering indices, and the deep-red color rendering R9 is an important challenge in the field of solid-state lighting. Herein, we report on a pure white hybrid light-emitting device combining a deep-blue emission from a polymer with blue, green, and red emissions from ternary CdSe/ZnS quantum dots. By carefully designing the device structure and tuning the ratio of QDs with different sizes, high CRI of 94 and R9 of 92 at 525 cd/m(2) were achieved.
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Incidence of malaria and risk factors in Italian travelers to malaria endemic countries.
Travel Med Infect Dis
PUBLISHED: 02-01-2010
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Imported malaria has been an increasing problem in Italy in the last three decades of the 1900s, representing the main risk for travelers visiting tropical and sub-tropical countries where malaria is endemic. Even though the total number of imported cases has been declining since 2000, malaria still represents the most frequent notifiable imported disease in Italy. The present study analyzes all the malaria cases reported in Italy in 2000-2006 in order to assess the trend of incidence over the time and reviewing the risk factors for travelers visiting malaria endemic countries.
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Protective effect of polyphenols from Glycyrrhiza glabra against oxidative stress in Caco-2 cells.
J Med Food
PUBLISHED: 12-23-2009
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In the present article, we have investigated the antioxidant properties of methanolic liquorice polyphenol extracts (LPE(s)). Polyphenol extraction was performed with 60% and 100% methanol. Analysis of LPE(s) by thin-layer chromatography revealed that a higher amount of polyphenols was recovered by extraction with 60% methanol. Antioxidant activity measurement of the reducing power, scavenging effect on 2,2-diphenyl-1-picrylhydrazyl free radical, and hydrogen peroxide scavenging capability have been taken as the parameters for assessment of antioxidant potential of LPE(s). Results have been compared with both natural and synthetic antioxidants. All experimental data have indicated that LPE(s) possess strong antioxidant power proportional to their o-diphenolic and total polyphenolic content, independently from the assay used. Therefore, the LPE(s) antioxidant property was examined against the cytotoxic effects of reactive oxygen species in human colon carcinoma cells. Pretreatment of Caco-2 cells with liquorice polyphenolic extracts provided a remarkable protection against oxidative damage induced by H(2)O(2). The highest oxidative stress protection (72% of cell vitality) was measured in cells pretreated with 0.54 mM polyphenols. This effect seems to be associated to the antioxidant activity of liquorice polyphenolic compounds. Our data suggest that polyphenols from Glycyrrhiza glabra could exert a beneficial action in the prevention of intestinal pathologies related to production of reactive oxygen species.
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The cyclin-dependent kinase inhibitor PHA-848125 suppresses the in vitro growth of human melanomas sensitive or resistant to temozolomide, and shows synergistic effects in combination with this triazene compound.
Pharmacol. Res.
PUBLISHED: 09-03-2009
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PHA-848125 is a novel cyclin-dependent kinase inhibitor under Phase I/II clinical investigation. In this study, we describe, for the first time, the effect of PHA-848125 on human melanoma cells in vitro. Seven melanoma cell lines with different sensitivity to temozolomide (TMZ) were exposed to PHA-848125 for 5 days and then assayed for cell growth. In all cases, including TMZ-resistant cells, PHA-848125 IC(50) values were significantly below the maximum plasma concentrations achievable in the clinic. In the most PHA-848125-sensitive cell line, the drug caused a concentration-dependent G(1) arrest. PHA-848125 also impaired phosphorylation of the retinoblastoma protein at CDK2 and CDK4 specific sites, decreased retinoblastoma protein and cyclin A levels, and increased p21(Cip1), p27(Kip1) and p53 expression. Combined treatment with fixed ratios of TMZ plus PHA-848125 was studied in three melanoma cell lines. PHA-848125 was added to the cells 48 h after TMZ and cell growth was evaluated after 3 additional days of culture. Parallel experiments were performed in the presence of O(6)-benzylguanine (BG), to prevent repair of methyl adducts at O(6)-guanine induced by TMZ. Drug combination of TMZ plus BG and PHA-848125 produced additive or synergistic effects on cell growth, depending on the cell line. In the absence of BG, the combination was still more active than the single agents in the cell line moderately sensitive to TMZ, but comparable to PHA-848125 alone in the two TMZ-resistant cell lines. When TMZ plus BG were used in combination with PHA-848125 against cultured normal melanocytes, neither synergistic nor additive antiproliferative effects were observed. Our results indicate that PHA-848125 can have a therapeutic potential in melanoma patients, alone or combined with TMZ. Moreover this agent appears to be particularly attractive on the bases of its effectiveness against TMZ-resistant melanoma cells.
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Enhanced fluorescence by metal nanospheres on metal substrates.
Opt Lett
PUBLISHED: 08-04-2009
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We investigate the metal enhanced fluorescence by silver nanospheres on a thin silver substrate. Experimental measurements for core/shell colloidal nanocrystals embedded in a polymer matrix show a fluorescence enhancement factor of about 9. We apply the discrete dipole approximation method to describe the local-field enhancement factor (LFEF). We find that the observed fluorescence enhancement is related to the broad LFEF profile induced by the substrate.
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Altered expression of selected microRNAs in melanoma: antiproliferative and proapoptotic activity of miRNA-155.
Int. J. Oncol.
PUBLISHED: 07-07-2009
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Altered expression of microRNAs (miRNAs) has been detected in cancer, suggesting that these small non-coding RNAs can act as oncogenes or tumor suppressor genes. In the present study, we investigated the expression of miRNA-17-5p, miRNA-18a, miRNA-20a, miRNA-92a, miRNA-146a, miRNA-146b and miRNA-155 by real-time quantitative RT-PCR in a panel of melanocyte cultures and melanoma cell lines and explored the possible role of miRNA-155 in melanoma cell proliferation and survival. The analyzed miRNAs were selected on the basis of previous studies strongly supporting their involvement in cancer development and/or progression. We found that miRNA-17-5p, miRNA-18a, miRNA-20a, and miRNA-92a were overexpressed, whereas miRNA-146a, miRNA-146b and miRNA-155 were down-regulated in the majority of melanoma cell lines with respect to melanocytes. Ectopic expression of miRNA-155 significantly inhibited proliferation in 12 of 13 melanoma cell lines with reduced levels of this miRNA and induced apoptosis in 4 out of 4 cell lines analyzed. In conclusion, our data further support the finding of altered miRNA expression in melanoma cells and establish for the first time that miRNA-155 is a negative regulator of melanoma cell proliferation and survival.
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The risk of malaria in travelers to India.
J Travel Med
PUBLISHED: 06-23-2009
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Several countries have reported a decline in malaria cases imported by travelers returning from India.
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Engineering transfer of micro- and nanometer-scale features by surface energy modification.
Langmuir
PUBLISHED: 05-02-2009
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Micropatterning of surfaces is gaining importance in various applications ranging from biosensors to microfluidic and lab-on-a-chip devices, where the control of the surface chemistry is of great importance for the application. In this paper, we introduce a patterning technique of topographical features, which is applicable on different substrates by modifying their surface energy. The textured surface is obtained via polydimethylsiloxane (PDMS) transfer, and the topographical parameters can be systematically tailored by selective treatment with oxygen plasma of either the PDMS stamp, the substrate, or both. Our approach is an alternative technique to create micro- and nanopatterns of various height and shape over a large area on different substrates. The possibility to control cell behavior on different surfaces tailored with this microtransfer patterning approach was also evaluated. The cell culture on patterned surfaces showed the possibility of modulating cell adhesion. Our method is based on simple transfer of silicone elastomeric patterns to the surface, and therefore, it is very simple and fast compared to other complex techniques. These observations could have implications for tissue-scaffold engineering science in areas such as microfluidic devices and control of cell adhesion.
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In the rat maximal dentate activation model of partial complex epilepsy, the anticonvulsant activity of levetiracetam is modulated by nitric oxide-active drugs.
J Neural Transm
PUBLISHED: 04-21-2009
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The effects of nitric oxide-active drugs on the anticonvulsant action of the antiepileptic drug levetiracetam in an experimental model of partial complex seizures named maximal dentate gyrus activation were studied in rats. Levetiracetam was given alone or in combination with 7-nitroindazole, a preferential inhibitor of neuronal nitric oxide synthase, or with L: -arginine, the precursor of nitric oxide synthesis. The maximal dentate activation parameters were the time of latency and the durations of maximal dentate activation and afterdischarge responses. The administration of levetiracetam showed an anticonvulsant effect that was increased when given in combination with 7-nitroindazole. The co-administration of levetiracetam and L: -arginine, which is pro-convulsant, did not significantly modify all the parameters. The present results indicate that the acute administration of levetiracetam, at the lower effective dose, exerts an efficacious inhibitory effect on the severity of maximal dentate activation seizures. Levetiracetam-induced antiepileptic effect is significantly increased by the simultaneous inhibition of neuronal nitric oxide synthase.
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Nitric oxide- and cGMP-active compounds affect the discharge of substantia nigra pars reticulata neurons: in vivo evidences in the rat.
J Neural Transm
PUBLISHED: 03-17-2009
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The nitric oxide (NO)-active drugs influence on the bioelectric activity of neurons of the pars reticulata of the substantia nigra was studied in urethane-anesthetized rats. A first group of animals was treated with 7-nitro-indazole (7-NI), a preferential inhibitor of neuronal NO synthase. In a second group of rats, electrophysiological recordings were coupled with microiontophoretic administration of Nomega-nitro-L-arginine methyl ester (L-NAME, a NO synthase inhibitor), 3-morpholino-sydnonimin-hydrocloride (SIN-1, a NO donor) and 8-Br-cGMP (a cell-permeable analogue of cGMP, the main second-messenger of NO neurotransmission). 7-NI and L-NAME caused a statistically significant decrease in the firing rate of most of the responsive cells, while application of SIN-1 and 8-Br-CGMP induced statistically significant excitatory effects. The results suggest a NO mediated excitatory modulation of the SNr neurons activity with a possible involvement of the cGMP pathway.
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Distribution of phage-associated virulence genes in pharyngeal group a streptococcal strains isolated in Italy.
J. Clin. Microbiol.
PUBLISHED: 03-11-2009
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The presence and assortment of 16 known virulence/resistance genetic determinants carried by prophages or prophage-like elements were tested in 212 clinical group A Streptococcus (GAS) strains and related to available data from SmaI macrorestriction/pulsed-field gel electrophoresis analysis and emm typing. A strong correlation existed among the three analyses. This finding supports the substantial contribution to the evolution and diversification of the GAS genome attributed to phages.
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Intensity of GABA-evoked responses is modified by nitric oxide-active compounds in the subthalamic nucleus of the rat: a microiontophoretic study.
J. Neurosci. Res.
PUBLISHED: 03-10-2009
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We have previously described modulatory effects of nitric oxide (NO)-active drugs on subthalamic nucleus (STN) neurons. In this study, the effects of microiontophoretically applied NO-active compounds on GABA-evoked responses were investigated in subthalamic neurons extracellularly recorded from anesthetized rats: 45 of 62 cells were excited by S-nitroso-glutathione (SNOG), an NO donor, whereas 28 of 43 neurons were inhibited by Nomega-nitro-L-arginine methyl ester (L-NAME), a NOS inhibitor. Nearly all neurons responding to SNOG and/or L-NAME showed significant inhibitory responses to the administration of iontophoretic GABA. In these cells, the changes induced by NO-active drugs in the magnitude of GABA-evoked responses were used as indicators of NO modulation. In fact, when an NO-active drug was co-iontophoresed with GABA, significant changes in GABA-induced responses were observed: generally, decreased magnitudes of GABA-evoked responses were observed during continuous SNOG ejection, whereas the administration of L-NAME enhanced GABA responses. In contrast, glutamate-evoked responses were enhanced by SNOG and dampened by L-NAME co-iontophoresis. Furthermore, the iontophoretic administration of bicuculline (a GABA(A) receptor antagonist) completely abolished the GABA-evoked inhibitory responses and reduced the magnitude of both the SNOG- and L-NAME-induced effects. The results suggest that the NO-mediated modulation of subthalamic neurons could also be a result of an interaction between NO and GABA(A) neurotransmission. Increased NOS activity has been shown in the hyperactive STN neurons of parkinsonian patients; on the basis of our observations about the influence of NO-active drugs on the baseline and GABA-evoked activity of subthalamic cells, such hyperactivity suggests the involvement of increased NO levels and reduced sensitivity to GABA.
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Imported malaria in children in industrialized countries, 1992-2002.
Emerging Infect. Dis.
PUBLISHED: 02-06-2009
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Children account for an appreciable proportion of total imported malaria cases, yet few studies have quantified these cases, identified trends, or suggested evidence-based prevention strategies for this group of travelers. We therefore sought to identify numbers of cases and deaths, Plasmodium species, place of malaria acquisition, preventive measures used, and national origin of malaria in children. We analyzed retrospective data from Australia, Denmark, France, Germany, Italy, Japan, the Netherlands, Sweden, Switzerland, the United Kingdom, and the United States and data provided by the United Nations World Tourism Organization. During 1992-2002, >17,000 cases of imported malaria in children were reported in 11 countries where malaria is not endemic; most (>70%) had been acquired in Africa. Returning to country of origin to visit friends and relatives was a risk factor. Malaria prevention for children should be a responsibility of healthcare providers and should be subsidized for low-income travelers to high-risk areas.
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Influence of variable substrate geometry on wettability and cellular responses.
J Colloid Interface Sci
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In this report, we evaluate the impact of a systematic change to the extracellular environment on cell morphology and functionality by combining the inherent properties of biocompatible polymers such as polydimethylsiloxane and polycaprolactone with a specific surface response. By microstructuring pillars and pits on the substrates, varying spacing and height of the structures, we investigate the role of topography in fibroblast cell adhesion and viability. The change of wetting behaviour was tailored and evaluated in terms of contact angle measurements. It was shown that the range of micro-scale physical cues at the interface between the cells and the surrounding environment affects cell shape and migrations, indicating a tendency to respond differently to higher features of the micro-scale. We found that surface topography seems dominant over material wettability, fibroblasts responded to variations in topography by altering morphology and migrating along the direction of spacing among the features biased by the height of structures and not by the material. It is therefore possible to selectively influence either cell adhesion or morphology by choosing adequate topography of the surface. This work can impact in the design of biomaterials and can be applied to implanted biomedical devices, tissue engineering scaffolds and lab on chip devices.
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NF-?B is activated in response to temozolomide in an AKT-dependent manner and confers protection against the growth suppressive effect of the drug.
J Transl Med
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Most DNA-damaging chemotherapeutic agents activate the transcription factor nuclear factor ?B (NF-?B). However, NF-?B activation can either protect from or contribute to the growth suppressive effects of the agent. We previously showed that the DNA-methylating drug temozolomide (TMZ) activates AKT, a positive modulator of NF-?B, in a mismatch repair (MMR) system-dependent manner. Here we investigated whether NF-?B is activated by TMZ and whether AKT is involved in this molecular event. We also evaluated the functional consequence of inhibiting NF-?B on tumor cell response to TMZ.
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Acetyl-L-carnitine improves behavior and dendritic morphology in a mouse model of Rett syndrome.
PLoS ONE
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Rett syndrome (RTT) is a devastating neurodevelopmental disorder affecting 1 in 10,000 girls. Approximately 90% of cases are caused by spontaneous mutations in the X-linked gene encoding methyl-CpG-binding protein 2 (MeCP2). Girls with RTT suffer from severe motor, respiratory, cognitive and social abnormalities attributed to early deficits in synaptic connectivity which manifest in the adult as a myriad of physiological and anatomical abnormalities including, but not limited to, dimished dendritic complexity. Supplementation with acetyl-L-carnitine (ALC), an acetyl group donor, ameliorates motor and cognitive deficits in other disease models through a variety of mechanisms including altering patterns of histone acetylation resulting in changes in gene expression, and stimulating biosynthetic pathways such as acetylcholine. We hypothesized ALC treatment during critical periods in cortical development would promote normal synaptic maturation, and continuing treatment would improve behavioral deficits in the Mecp2(1lox) mouse model of RTT. In this study, wildtype and Mecp2(1lox) mutant mice received daily injections of ALC from birth until death (postnatal day 47). General health, motor, respiratory, and cognitive functions were assessed at several time points during symptom progression. ALC improved weight gain, grip strength, activity levels, prevented metabolic abnormalities and modestly improved cognitive function in Mecp2 null mice early in the course of treatment, but did not significantly improve motor or cognitive functions assessed later in life. ALC treatment from birth was associated with an almost complete rescue of hippocampal dendritic morphology abnormalities with no discernable side effects in the mutant mice. Therefore, ALC appears to be a promising therapeutic approach to treating early RTT symptoms and may be useful in combination with other therapies.
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Differences between axes depend on where you set the bar: associations among symptoms, interpersonal relationship and alexithymia with number of personality disorder criteria.
J. Pers. Disord.
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Personality disorders are better understood as entities that vary according to severity along specific domains rather than a phenomenon separate from and unrelated to Axis I disorders. This study explores whether patients who were rated as having greater numbers of personality disorder traits reported greater levels of interpersonal problems, psychiatric symptoms, and alexithymia. The sample was composed of 506 consecutive patients assessed in a private outpatient center who were administered the SCID-II Symptom-Checklist (SCL-90-R), Inventory of Interpersonal Problems (IIP-47), and Toronto Alexithymia-Scale (TAS-.20). Based upon the number of personality disorder traits identified in the SCID, participants were classified into five groups: 0-4, 5-9, 10-14, 15-19, and 20 or more personality disorder traits met. Comparisons between groups revealed that symptom severity and levels of interpersonal problems increased between groups as the number of personality disorder traits increased. After covarying for symptom severity, there were no significant between-groups differences for levels of alexithymia. Findings are consistent with the claims that the simple Axis I-Axis II distinction is not an optimal strategy to understand personality pathology. It instead may be more fruitful to consider group differences in terms of numbers of personality disorder traits met.
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Physiological and agonistic behavioural response of Procambarus clarkii to an acoustic stimulus.
J. Exp. Biol.
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This study examined the effects of an acoustic stimulus on the haemolymph and agonistic behaviour of the red swamp crayfish, Procambarus clarkii. The experiment was conducted in a tank equipped with a video recording system using six groups (three control and three test groups) of five adult crayfish (30 specimens in total). After 1 h of habituation, the behaviour of the crayfish was monitored for 2 h. During the second hour, the animals in the test groups were exposed to a linear sweep (frequency range 0.1-25 kHz; peak amplitude 148 dB(rms) re. 1 ?Pa at 12 kHz) acoustic stimulus for 30 min. Exposure to the noise produced significant variations in haemato-immunological parameters as well as a reduction in agonistic behaviour.
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The underwater acoustic activities of the red swamp crayfish Procambarus clarkii.
J. Acoust. Soc. Am.
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This study describes the underwater acoustic behavior of the red swamp crayfish Procambarus clarkii. The study was conducted both in a tank and in the natural environment. The tank was equipped with video and acoustic recording systems. Observations were conducted to identify the underwater acoustic signals produced and their association with behavioral events and the movement status of the animals. In a lake in a natural reserve, a remote acoustic recording station was used to study the circadian underwater acoustic activity of the crayfish and to assess the acoustic features of the signals. The red swamp crayfish produces irregular trains of wide-band pulses (duration 0.4 ms, SPL(PK) 128 dB re 1 ?Pa, peak frequency 28 kHz, bandwidth(RMS) 20 kHz). The production of signals is positively related to intraspecific interactions (encounter/approach, fighting and successive Tail Flips). In the natural environment, acoustic activity is almost absent during the day, increases abruptly at sunset and continues until dawn. This study reveals the previously unknown underwater acoustic signals of Procambarus clarkii and the potential of passive acoustic methods to monitor the presence, the abundance and the behavioral activities of this invasive species.
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The development of the Metacognition Assessment interview: instrument description, factor structure and reliability in a non-clinical sample.
Psychiatry Res
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Metacognition is a multi-facet psychological construct; deficits in metacognitive abilities are associated to low social functioning, low quality of life, psychopathology, and symptoms. The aim of this study was to describe and develop a valid and reliable interview for assessing metacognition.
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Effect of Annurca apple polyphenols on human HaCaT keratinocytes proliferation.
J Med Food
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Polyphenols have been demonstrated to have clear antioxidant activities in vitro. However, in complex biological systems, they exhibit additional properties, which are yet poorly understood. The apple is among the most consumed fruits worldwide, and several studies suggest that apple polyphenols could play a role in the prevention of degenerative diseases. The present study aimed at evaluating the Annurca apple polyphenol extract (APE) effects both proliferation and apoptosis on HaCaT cells. The data indicate that apple polyphenolic compounds had significant antiproliferative action on HaCaT cells. The fluorescence-activated cell-sorting analysis showed that APE induced cell apoptosis in a dose-dependent manner. Moreover, apple polyphenols induced apoptosis in epithelial cells by triggering a death receptor-associated extrinsic pathway p53-independent. APE was also capable of inducing morphological changes as evidenced by nuclear condensation. The cellular, morphological, and molecular data unequivocally demonstrated that induction of cellular apoptosis was mainly responsible for the previously observed antiproliferation-induced APE on HaCaT keratinocytes. Our experimental results suggest that apple polyphenols are a promising source from which a natural-based topical agent could be developed for skin diseases treatment.
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Micropatterned polyelectrolyte nanofilms promote alignment and myogenic differentiation of C2C12 cells in standard growth media.
Biotechnol. Bioeng.
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Alignment of skeletal myoblasts is considered a critical step during myotube formation. The C2C12 cell line is frequently used as a model of skeletal muscle differentiation that can be induced by lowering the serum concentration in standard culture flasks. In order to mimic the striated architectures of skeletal muscles in vitro, micro-patterning techniques and surface engineering have been proven as useful approaches for promoting elongation and alignment of C2C12 myoblasts, thereby enhancing the outgrowth of multi-nucleated myotubes upon switching from growth media (GM) to differentiative media (DM). Herein, a layer-by-layer (LbL) polyelectrolyte multilayer deposition was combined with a micro-molding in capillaries (MIMIC) method to simultaneously provide biochemical and geometrical instructive cues that induced the formation of tightly apposed and parallel arrays of differentiating myotubes from C2C12 cells maintained in GM media for 15 days. This study focuses on two different types of patterned/self-assembled nanofilms based on alternated layers of poly (allylamine hydrochloride) (PAH)/poly(sodium 4-styrene-sulfonate) (PSS) as biocompatible but not biodegradable polymeric structures, or poly-L-arginine sulfate salt (pARG)/dextran sulfate sodium salt (DXS) as both biocompatible and biodegradable surfaces. The influence of these microstructures as well as of the nanofilm composition on C2C12 skeletal muscle cells differentiation and viability was evaluated and quantified, pointing to give a reference for skeletal muscle regenerative potential in culture conditions that do not promote it. At this regard, our results validate PEM microstructured devices, to a greater extent for (PAH/PSS)?-coated microgrooves, as biocompatible and innovative tools for tissue engineering applications and molecular dissection of events controlling C2C12 skeletal muscle regeneration without switching to their optimal differentiative culture media in vitro.
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Down-regulation of the PTTG1 proto-oncogene contributes to the melanoma suppressive effects of the cyclin-dependent kinase inhibitor PHA-848125.
Biochem. Pharmacol.
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We previously demonstrated that PHA-848125, a cyclin-dependent kinase inhibitor presently under Phase II clinical investigation, impairs melanoma cell growth. In this study, gene expression profiling showed that PHA-848125 significantly modulated the expression of 128 genes, predominantly involved in cell cycle control, in the highly drug-sensitive GL-Mel (p53 wild-type) melanoma cells. Up-regulation of 4 selected genes (PDCD4, SESN2, DDIT4, DEPDC6), and down-regulation of 6 selected genes (PTTG1, CDC25A, AURKA, AURKB, PLK1, BIRC5) was confirmed at protein levels. The same protein analysis performed in PHA-848125-treated M10 melanoma cells - p53 mutated and less sensitive to the drug than GL-Mel cells - revealed no DEPDC6 expression and no changes of PTTG1, PDCD4 and BIRC5 levels. Upon PHA-848125 treatment, a marked PTTG1 down-modulation was also observed in A375 cells (p53 wild-type) but not in CN-Mel cells (p53 mutated). PTTG1 silencing significantly inhibited melanoma cell proliferation and induced senescence, with effects less pronounced in p53 mutated cells. PTTG1 silencing increased PHA-848125 sensitivity of p53 mutated cells but not that of A375 or GL-Mel cells. Accordingly, in M10 but not in A375 cells a higher level of senescence was detected in PHA-848125-treated/PTTG1-silenced cells with respect to PHA-848125-treated controls. In A375 and GL-Mel cells, TP53 silencing attenuated PHA-848125-induced down-modulation of PTTG1 and decreased cell sensitivity to the drug. These findings indicate that PHA-848125-induced down-regulation of PTTG1 depends, at least in part, on p53 function and contributes to the antiproliferative activity of the drug. Our study provides further molecular insight into the antitumor mechanism of PHA-848125.
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Abnormal isoaspartyl residues in erythrocyte membranes from psoriatic patients.
Arch. Dermatol. Res.
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Spontaneous protein deamidation of labile asparagines (Asn), generating abnormal isoaspartyl residues (IsoAsp), is associated with cell aging and enhanced by an oxidative microenvironment. The presence of isopeptide bonds impairs protein structure/function and can trigger autoimmune responses. To minimize the damage, IsoAsp can be "repaired" by a specific L-isoaspartate-(D-aspartate)-protein-O-methyltransferase. The condition of chronic oxidative stress reported in psoriatic patients, and the potential etiological role of unknown self-antigens, prompted us to investigate Asn deamidation in psoriatic tissues. Erythrocytes (RBC) were selected as the model system since, lacking protein synthesis apparatus, they are unable to replace damaged proteins. Blood samples were obtained from 36 patients and 34 controls. L-isoAsp content was highly increased in RBC membrane proteins from psoriatic patients. Deamidated species included ankyrin, band 4.1, band 4.2 and the integral membrane protein band 3. A functional analysis demonstrated that this result was unrelated to a reduced efficiency of the S-adenosylmethionine-dependent repair system suggesting an increased protein instability at Asn sites, responsible for IsoAsp accumulation in psoriatic patients.
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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.

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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.