506 research outputs found

    Photocatalytic lithography with atomic layer deposited TiO2 films to tailor biointerface properties

    Get PDF
    In this article, the use of thin, photocatalytically active TiO2 films deposited using atomic layer deposition (ALD) and a conventional lithography mask are explored for the fabrication of a patterned biointerface. Hereto, a pattern of self-assembled monolayers (SAMs) with different functional groups is created using ALD TiO2 films, anatase-rich as-deposited, with a thickness of 20 nm and a short UV exposure time of 5 min. More specifically, azido-containing SAMs are locally removed upon UV exposure ( = 308 nm) and the created gaps are filled with a polyethylene glycol (PEG) SAM, hereby creating a surface with areas for the selective coupling of biomolecules via the azide groups and antifouling areas due to the presence of the PEG. To demonstrate the effectiveness of this approach, fluorescent-labeled antibodies are immobilized on the well-defined patterns with a resolution in the mu m range

    ATP Augments von Willebrand Factor-dependent Shear-induced Platelet Aggregation through Ca2+-Calmodulin and Myosin Light Chain Kinase Activation

    Full text link
    peer reviewedShear stress triggers von Willebrand factor (VWF) binding to platelet glycoprotein Ibalpha and subsequent integrin alpha(IIb)beta(3)-dependent platelet aggregation. Concomitantly, nucleotides are released from plateletdense granules, and ADP is known to contribute to shear-induced platelet aggregation (SIPA). This study shows that ATP also contributes to SIPA. The ATP-gated P2X(1) ion channel induces MLC-mediated cytoskeletal rearrangements that increases platelet degranulation during VWF-triggered platelet activation

    Effect of high-dose N-acetylcysteine on airway geometry, inflammation, and oxidative stress in COPD patients

    Get PDF
    Background: Previous studies have demonstrated the potential beneficial effect of N-acetylcysteine (NAC) in chronic obstructive pulmonary disease (COPD). However, the required dose and responder phenotype remain unclear. The current study investigated the effect of high-dose NAC on airway geometry, inflammation, and oxidative stress in COPD patients. Novel functional respiratory imaging methods combining multislice computed tomography images and computer-based flow simulations were used with high sensitivity for detecting changes induced by the therapy. Methods: Twelve patients with Global Initiative for Chronic Obstructive Lung Disease stage II COPD were randomized to receive NAC 1800 mg or placebo daily for 3 months and were then crossed over to the alternative treatment for a further 3 months. Results: Significant correlations were found between image-based resistance values and glutathione levels after treatment with NAC (P = 0.011) and glutathione peroxidase at baseline (P = 0.036). Image-based resistance values appeared to be a good predictor for glutathione peroxidase levels after NAC (P = 0.02), changes in glutathione peroxidase levels (P = 0.035), and reduction in lobar functional residual capacity levels (P = 0.00084). In the limited set of responders to NAC therapy, the changes in airway resistance were in the same order as changes induced by budesonide/formoterol. Conclusion: A combination of glutathione, glutathione peroxidase, and imaging parameters could potentially be used to phenotype COPD patients who would benefit from addition of NAC to their current therapy. The findings of this small pilot study need to be confirmed in a larger pivotal trial

    Sequestration of human cytomegalovirus by human renal and mammary epithelial cells

    Get PDF
    AbstractUrine and breast milk represent the main routes of human cytomegalovirus (HCMV) transmission but the contribution of renal and mammary epithelial cells to viral excretion remains unclear. We observed that kidney and mammary epithelial cells were permissive to HCMV infection and expressed immediate early, early and late antigens within 72h of infection. During the first 24h after infection, high titers of infectious virus were measured associated to the cells and in culture supernatants, independently of de novo synthesis of virus progeny. This phenomenon was not observed in HCMV-infected fibroblasts and suggested the sequestration and the release of HCMV by epithelial cells. This hypothesis was supported by confocal and electron microscopy analyses. The sequestration and progressive release of HCMV by kidney and mammary epithelial cells may play an important role in the excretion of the virus in urine and breast milk and may thereby contribute to HCMV transmission

    Granulomatous skin lesions complicating Varicella infection in a patient with Rothmund-Thomson syndrome and immune deficiency: case report

    Get PDF
    Rothmund-Thomson syndrome (RTS)(OMIM 268400) is a rare autosomal recessive genodermatosis characterized by poikiloderma, small stature, skeletal and dental abnormalities, cataract and an increased risk of cancer. It is caused by mutations in RECQL4 at 8q24. Immune deficiency is not described as a classical feature of the disease. Here we report the appearance of granulomatous skin lesions complicating primary Varicella Zoster Virus infection in a toddler with Rothmund Thomson syndrome and immune deficiency. Although granulomatous disorders are sometimes seen after Herpes zoster, they are even more rare after Varicella primary infection. Granulomas have hitherto not been described in Rothmund-Thomson syndrome. With this report we aim to stress the importance of screening for immune deficiency in patients with Rothmund-Thomson syndrome

    The effects of extrafine beclometasone/formoterol (BDP/F) on lung function, dyspnea, hyperinflation, and airway geometry in COPD patients: novel insight using functional respiratory imaging

    Get PDF
    Background: The efficacy of inhaled corticosteroids (ICS) in moderately severe COPD patients remains unclear. At the same time, the use of extrafine particles in COPD patients is a topic of ongoing research. Objectives: This study assessed the effect of ICS in steroid-naive mild COPD patients and the effect of reducing the ICS dose in more severe COPD patients previously using ICS when switching to an extrafine particle BDP/F formulation (Foster using Modulite technology, Chiesi Pharmaceutici, Parma, Italy). Methods: Novel functional respiratory imaging (FRI) methods, consisting of multi-slice CT scans and Computational Fluid Dynamics, were used in combination with conventional pulmonary function tests and patient reported outcomes. Results: The study showed that the administration of extrafine BDP/F after 4-6 h led to a significant improvement in lung function parameters and hyperinflation as determined by spirometry, body plethysmography, and functional respiratory imaging. After 6 months of treatment, it was observed that, compared to baseline, the hyperinflation on lobar level at total lung capacity was significantly reduced (-1.19 +/- 7.19 %p, p=0.009). In addition, a significant improvement in SGRQ symptom score was noted in the entire patient population. Patients who improved in terms of hyperinflation also improved their MMRC dyspnea score. CFD indicated a difference in regional deposition between extrafine and non-extrafine formulations with -11% extrathoracic deposition and up to +4% lobe deposition for the extrafine formulation. Conclusions: The study showed that the administration of extrafine BDP/F improved lung function parameters and hyperinflation. Patients previously treated with ICS remained stable despite the lower dose, while ICS naive patients improved in terms of lobar hyperinflation. FRI seems to be a sensitive biomarker to detect clinically relevant changes that are not detected by spirometry. The next step is to confirm these findings in a controlled trial

    Generation of hepatocyte- and endocrine pancreatic-like cells from human induced endodermal progenitor cells

    Get PDF
    Multipotent Adult Progenitor Cells (MAPCs) are one potential stem cell source to generate functional hepatocytes or β-cells. However, human MAPCs have less plasticity than pluripotent stem cells (PSCs), as their ability to generate endodermal cells is not robust. Here we studied the role of 14 transcription factors (TFs) in reprogramming MAPCs to induced endodermal progenitor cells (iENDO cells), defined as cells that can be long-term expanded and differentiated to both hepatocyte- and endocrine pancreatic-like cells. We demonstrated that 14 TF-iENDO cells can be expanded for at least 20 passages, differentiate spontaneously to hepatocyte-, endocrine pancreatic-, gut tube-like cells as well as endodermal tumor formation when grafted in immunodeficient mice. Furthermore, iENDO cells can be differentiated in vitro into hepatocyte- and endocrine pancreatic-like cells. However, the pluripotency TF OCT4, which is not silenced in iENDO cells, may contribute to the incomplete differentiation to mature cells in vitro and to endodermal tumor formation in vivo. Nevertheless, the studies presented here provide evidence that reprogramming of adult stem cells to an endodermal intermediate progenitor, which can be expanded and differentiate to multiple endodermal cell types, might be a valid alternative for the use of PSCs for creation of endodermal cell types

    Bir ailenin devr-i hayatı

    Get PDF
    Melikzade Fuat'ın Ahenk'te tefrika edilen Bir Ailenin Devr-i Hayatı adlı romanıTefrikanın devamına rastlanmamış, tefrika yarım kalmıştır

    Fetal Rat Hearts Do Not Display Acute Cardiotoxicity in Response to Maternal Doxorubicin Treatment s

    Get PDF
    ABSTRACT Anthracyclines are used to treat cancers during the second and third trimester of pregnancy. The chemotherapeutic effect of anthracyclines is associated with a dose-and time-dependent cardiotoxicity that is well described for infants and adults. However, data regarding fetal anthracycline-related cardiotoxicity after administration of chemotherapeutics during pregnancy are limited. In this study, we analyzed the acute effect of doxorubicin, an anthracycline derivative, on fetal and maternal rat myocardium. We injected 10 or 20 mg/kg i.v. doxorubicin to pregnant Wistar rats at day 18 of pregnancy; age-matched pregnant rats injected with physiologic saline served as controls. Maternal echocardiography and fetal Doppler scanning were performed before the injection and before sacrifice. Cesarean operation was performed at day 19 or 20, and maternal and fetal blood samples and heart biopsies were collected to measure apoptosis, the impact on cell proliferation, and structural cardiac damage. Acute maternal cardiotoxicity is associated with loss of body weight, moderately deteriorated left ventricular function, induction of apoptosis, and a decrease in cell turnover. Despite a 30% lower fetal body weight and elevated plasma B-type natriuretic peptide concentrations after doxorubicin administration, the fetal hearts had intact microstructure, an unaltered number of apoptotic cells, and preserved cell proliferation compared with controls. Our study suggests that acute treatment using anthracyclines during pregnancy impairs maternal cardiac function, whereas fetal hearts are protected
    corecore