431 research outputs found

    Presence of HIF-1 and related genes in normal mucosa, adenomas and carcinomas of the colorectum

    Get PDF
    Expression of the transcription factor hypoxia-inducible factor 1 (HIF-1), which plays a key role in cellular adaptation to hypoxia, was investigated in normal colorectal mucosa (ten), adenomas (61), and carcinomas (23). Tissue samples were analyzed for HIF-1α, its upstream regulators, von Hippel–Lindau factor, AKT, and mammalian target of rapamycin (mTOR) and its downstream targets glucose transporter 1 (GLUT1), carbonic anhydrase IX, stromal-cell-derived factor 1 (SDF-1) by immunohistochemistry. In normal colorectal mucosa, HIF-1α was observed in almost all nuclei of surface epithelial cells, probably secondary to a gradient of oxygenation, as indicated by pimonidazole staining. The same staining pattern was present in 87% of adenomas. In carcinomas, HIF-1α was present predominantly around areas of necrosis (78%). Active AKT and mTOR, were present in all adenomas, carcinomas, and in normal colorectal mucosa. GLUT1 and SDF-1 were present in the normal surface epithelium of all adenoma cases, whereas in the carcinoma GLUT1 was located around necrotic regions and SDF-1 was present in all epithelial cells. In conclusion, HIF-1α appears to be physiologically expressed in the upper part of the colorectal mucosa. The present observations support that upregulation of HIF-1α and its downstream targets GLUT1 and SDF-1 in colorectal adenomas and carcinomas may be due to hypoxia, in close interaction with an active phosphatidylinositol 3-kinases–AKT–mTOR pathway

    Detection of codon 12 K- ras mutations in non-neoplastic mucosa from bronchial carina in patients with lung adenocarcinomas

    Get PDF
    K- ras activation by point mutation in codon 12 has been reported in lung adenocarcinomas in various models of experimental lung tumours induced by chemical carcinogens. The hypothesis of the presence of cells containing K- ras mutation in non neoplastic bronchial carina, the main site of impaction of airborne contaminants, was investigated by evaluating concurrent lung tumour and non-neoplastic proximal bronchial carinae from 19 patients with lung adenocarcinomas. The restriction fragment length polymorphism enriched PCR method used can detect one mutant allele among 103normal alleles. A mutation was detected in 42% of lung adenocarcinoma samples. No mutation was detected in either tumour or bronchial carinae in nine patients (47%). K- ras mutation was detected in the lung tumour but not in bronchial carinae in four patients (21%), in both the lung tumour and bronchial carinae in four other patients (21%). In two patients (11%), K- ras mutation was detected in at least one bronchial carina, but not in the lung tumour. Mutations of codon 12, confirmed by sequencing analysis of ten samples, were G to T transversion, mostly TGT and GTT in bronchial carinae and lung tumours. Our data show that activated K- ras by point mutation can be present in non-neoplastic bronchial carina mucosa even when no mutation is detected in tumour samples. © 2000 Cancer Research Campaig

    Clinically Translatable Cell Tracking and Quantification by MRI in Cartilage Repair Using Superparamagnetic Iron Oxides

    Get PDF
    Background: Articular cartilage has very limited intrinsic regenerative capacity, making cell-based therapy a tempting approach for cartilage repair. Cell tracking can be a major step towards unraveling and improving the repair process of these therapies. We studied superparamagnetic iron oxides (SPIO) for labeling human bone marrow-derived mesenchymal stem cells (hBMSCs) regarding effectivity, cell viability, long term metabolic cell activity, chondrogenic differentiation and hBMSC secretion profile. We additionally examined the capacity of synovial cells to endocytose SPIO from dead, labeled cells, together with the use of magnetic resonance imaging (MRI) for intra-articular visualization and quantification of SPIO labeled cells. Methodology/Prinicipal Findings: Efficacy and various safety aspects of SPIO cell labeling were determined using appropriate assays. Synovial SPIO re-uptake was investigated in vitro by co-labeling cells with SPIO and green fluorescent protein (GFP). MRI experiments were performed on a clinical 3.0T MRI scanner. Two cell-based cartilage repair techniques were mimicked for evaluating MRI traceability of labeled cells: intra-articular cell injection and cell implantation in cartilage defects. Cells were applied ex vivo or in vitro in an intra-articular environment and immediately scanned. SPIO labeling was effective and did not impair any of the studied safety aspects, including hBMSC secretion profile. SPIO from dead, labeled cells could be taken up by synovial cells. Both injected and implanted SPIO-labeled cells could accurately be visualized by MRI in a clinically relevant sized joint model using clinically applied cell doses. Finally, we quantified the amount of labeled cells seeded in cartilage defects using MR-based relaxometry. Conclusions: SPIO labeling appears to be safe without influencing cell behavior. SPIO labeled cells can be visualized in an intra-articular environment and quantified when seeded in cartilage defects.Biomechanical EngineeringMechanical, Maritime and Materials Engineerin

    Dutch home-based pre-reading intervention with children at familial risk of dyslexia

    Get PDF
    Children (5 and 6 years old, n = 30) at familial risk of dyslexia received a home-based intervention that focused on phoneme awareness and letter knowledge in the year prior to formal reading instruction. The children were compared to a no-training at-risk control group (n = 27), which was selected a year earlier. After training, we found a small effect on a composite score of phoneme awareness (d = 0.29) and a large effect on receptive letter knowledge (d = 0.88). In first grade, however, this did not result in beneficial effects for the experimental group in word reading and spelling. Results are compared to three former intervention studies in The Netherlands and comparable studies from Denmark and Australia

    Locomotion disorders and skin and claw lesions in gestating sows housed in dynamic versus static groups

    Get PDF
    Lameness and lesions to the skin and claws of sows in group housing are commonly occurring indicators of reduced welfare. Typically, these problems are more common in group housing than in individual housing systems. Group management type (dynamic versus static) and stage of gestation influence the behavior of the animals, which in turn influences the occurrence of these problems. The present study compared prevalence, incidence and mean scores of lameness and skin and claw lesions in static versus dynamic group housed sows at different stages of gestation during three consecutive reproductive cycles. A total of 10 Belgian sow herds were monitored; 5 in which dynamic groups and 5 in which static groups were utilized. All sows were visually assessed for lameness and skin lesions three times per cycle and the claws of the hind limbs were assessed once per cycle. Lameness and claw lesions were assessed using visual analogue scales. Static groups, in comparison with dynamic groups, demonstrated lower lameness scores (P<0.05) and decreased skin lesion prevalence (24.9 vs. 47.3%, P<0.05) at the end of gestation. There was no difference between treatment group regarding claw lesion prevalence with 75.5% of sows demonstrating claw lesions regardless of group management. Prevalences of lameness (22.4 vs. 8.9%, P<0.05) and skin lesions (46.6 vs. 4.4%, P<0.05) were highest during the group-housed phase compared to the individually housed phases. Although the prevalence of lameness and skin lesions did not differ three days after grouping versus at the end of the group-housing phase, their incidence peaked during the first three days after moving from the insemination stalls to the group. In conclusion, the first three days after grouping was the most risky period for lameness incidence, but there was no significant difference between static or dynamic group management

    Interactional justice at work is related to sickness absence: a study using repeated measures in the Swedish working population

    Get PDF
    Background: Research has shown that perceived unfairness contributes to higher rates of sickness absence. While shorter, but more frequent periods of sickness absence might be a possibility for the individual to get relief from high strain, long-term sickness absence might be a sign of more serious health problems. The Uncertainty Management Model suggests that justice is particularly important in times of uncertainty, e.g. perceived job insecurity. The present study investigated the association between interpersonal and informational justice at work with long and frequent sickness absence respectively, under conditions of job insecurity. Methods: Data were derived from the 2010, 2012, and 2014 biennial waves of the Swedish Longitudinal Occupational Survey of Health (SLOSH). The final analytic sample consisted of 19,493 individuals. We applied repeated measures regression analyses through generalized estimating equations (GEE), a method for longitudinal data that simultaneously analyses variables at different time points. We calculated risk of long and frequent sickness absence, respectively in relation to interpersonal and informational justice taking perceptions of job insecurity into account. Results: We found informational and interpersonal justice to be associated with risk of long and frequent sickness absence independently of job insecurity and demographic variables. Results from autoregressive GEE provided some support for a causal relationship between justice perceptions and sickness absence. Contrary to expectations, we found no interaction between justice and job insecurity. Conclusions: Our results underline the need for fair and just treatment of employees irrespective of perceived job insecurity in order to keep the workforce healthy and to minimize lost work days due to sickness absence

    Public Acceptability in the UK and USA of Nudging to Reduce Obesity: The Example of Reducing Sugar-Sweetened Beverages Consumption.

    Get PDF
    BACKGROUND: "Nudging"-modifying environments to change people's behavior, often without their conscious awareness-can improve health, but public acceptability of nudging is largely unknown. METHODS: We compared acceptability, in the United Kingdom (UK) and the United States of America (USA), of government interventions to reduce consumption of sugar-sweetened beverages. Three nudge interventions were assessed: i. reducing portion Size, ii. changing the Shape of the drink containers, iii. changing their shelf Location; alongside two traditional interventions: iv. Taxation and v. Education. We also tested the hypothesis that describing interventions as working through non-conscious processes decreases their acceptability. Predictors of acceptability, including perceived intervention effectiveness, were also assessed. Participants (n = 1093 UK and n = 1082 USA) received a description of each of the five interventions which varied, by randomisation, in how the interventions were said to affect behaviour: (a) via conscious processes; (b) via non-conscious processes; or (c) no process stated. Acceptability was derived from responses to three items. RESULTS: Levels of acceptability for four of the five interventions did not differ significantly between the UK and US samples; reducing portion size was less accepted by the US sample. Within each country, Education was rated as most acceptable and Taxation the least, with the three nudge-type interventions rated between these. There was no evidence to support the study hypothesis: i.e. stating that interventions worked via non-conscious processes did not decrease their acceptability in either the UK or US samples. Perceived effectiveness was the strongest predictor of acceptability for all interventions across the two samples. CONCLUSION: In conclusion, nudge interventions to reduce consumption of sugar-sweetened beverages seem similarly acceptable in the UK and USA, being more acceptable than taxation, but less acceptable than education. Contrary to prediction, we found no evidence that highlighting the non-conscious processes by which nudge interventions may work decreases their acceptability. However, highlighting the effectiveness of all interventions has the potential to increase their acceptability.The study was funded by the UK Department of Health Policy Research Programme (Policy Research Unit in Behaviour and Health) (Grant ID: PRUN-0409-10109)This is the final version of the article. It first appeared from the Public Library of Science via http://dx.doi.org/10.1371/journal.pone.015599

    The synergistic action of imidacloprid and flumethrin and their release kinetics from collars applied for ectoparasite control in dogs and cats

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The control of tick and flea burdens in dogs and cats has become essential to the control of important and emerging vector borne diseases, some of which are zoonoses. Flea worry and flea bite hypersensitivity are additionally a significant disease entity in dogs and cats. Owner compliance in maintaining the pressure of control measures has been shown to be poor. For these reasons efforts are continuously being made to develop ectoparasiticides and application methods that are safe, effective and easy to apply for pet owners. A new polymer matrix collar has recently been developed which is registered for 8 months use in cats and dogs. The basic properties of this collar have been investigated in several <it>in vitro </it>and <it>in vivo </it>studies.</p> <p>Methods</p> <p>The effects of imidacloprid, flumethrin and the combination were evaluated in vitro by means of whole cell voltage clamp measurement experiments conducted on isolated neuron cells from <it>Spodoptera frugiperda</it>. The in vitro efficacy of the two compounds and the combination against three species of ticks and their life stages and fleas were evaluated in a dry surface glass vial assay. The kinetics of the compounds over time in the collar were evaluated by the change in mass of the collar and measurement of the surface concentrations and concentrations of the actives in the collar matrix by HPLC. Hair clipped from collar treated dogs and cats, collected at various time points, was used to assess the acaricidal efficacy of the actives ex vivo.</p> <p>Results</p> <p>An <it>in vitro </it>isolated insect nerve model demonstrated the synergistic neurotoxic effects of the pyrethroid flumethrin and the neonicotinoid imidacloprid. An <it>in vitro </it>glass vial efficacy and mortality study against various life stages of the ticks <it>Ixodes ricinus, Rhipicephalus sanguineus </it>and <it>Dermacentor reticulatus </it>and against the flea (<it>Ctenocephalides felis</it>) demonstrated that the combination of these products was highly effective against these parasites. The release kinetics of these actives from a neck collar (compounded with 10% imidacloprid and 4.5% flumethrin) was extensively studied in dogs and cats under laboratory and field conditions. Acaricidal concentrations of the actives were found to be consistently released from the collar matrix for 8 months. None of the collar studies in dogs or cats were associated with any significant collar related adverse event.</p> <p>Conclusion</p> <p>Here we demonstrated the synergism between the pyrethroid flumethrin and the neonicotinoid imidacloprid, both provided in therapeutically relevant doses by a slow release collar matrix system over 8 months. This collar is therefore a convenient and safe tool for a long-term protection against ectoparasites.</p

    Clinicopathologic significance of HIF-1α, p53, and VEGF expression and preoperative serum VEGF level in gastric cancer

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Hypoxia influences tumor growth by inducing angiogenesis and genetic alterations. Hypoxia-inducible factor 1α (HIF-1α), p53, and vascular endothelial growth factor (VEGF) are all important factors in the mechanisms inherent to tumor progression. In this work, we have investigated the clinicopathologic significance of HIF-1α, p53, and VEGF expression and preoperative serum VEGF (sVEGF) level in gastric cancer.</p> <p>We immunohistochemically assessed the HIF-1α, p53, and VEGF expression patterns in 114 specimens of gastric cancer. Additionally, we determined the levels of preoperative serum VEGF (sVEGF).</p> <p>Results</p> <p>The positive rates of p53 and HIF-1α (diffuse, deep, intravascular pattern) were 38.6% and 15.8%, respectively. The VEGF overexpression rate was 57.9%. p53 and HIF-1α were correlated positively with the depth of invasion (<it>P </it>= 0.015, <it>P </it>= 0.001, respectively). Preoperative sVEGF and p53 levels were correlated significantly with lymph node involvement (<it>P </it>= 0.010, <it>P </it>= 0.040, respectively). VEGF overexpression was more frequently observed in the old age group (≥ 60 years old) and the intestinal type (<it>P </it>= 0.013, <it>P </it>= 0.014, respectively). However, correlations between preoperative sVEGF level and tissue HIF-1α, VEGF, and p53 were not observed. The median follow-up duration after operation was 24.5 months. HIF-1α was observed to be a poor prognostic factor of disease recurrence or progression (<it>P </it>= 0.002).</p> <p>Conclusion</p> <p>p53, HIF-1α and preoperative sVEGF might be markers of depth of invasion or lymph node involvement. HIF-1α expression was a poor prognostic factor of disease recurrence or progression in patients with gastric cancers.</p
    corecore