Loss of the PTCH1 tumor suppressor defines a new subset of plexiform fibromyxoma.

BackgroundPlexiform fibromyxoma (PF) is a rare gastric tumor often confused with gastrointestinal stromal tumor. These so-called "benign" tumors often present with upper GI bleeding and gastric outlet obstruction. It was recently demonstrated that approximately one-third of PF have activation of the GLI1 oncogene, a transcription factor in the hedgehog (Hh) pathway, via a MALAT1-GLI1 fusion protein or GLI1 up-regulation. Despite this discovery, the biology of most PFs remains unknown.MethodsNext generation sequencing (NGS) was performed on formalin-fixed paraffin-embedded (FFPE) samples of PF specimens collected from three institutions (UCSD, NCI and OHSU). Fresh frozen tissue from one tumor was utilized for in vitro assays, including quantitative RT-PCR and cell viability assays following drug treatment.ResultsEight patients with PF were identified and 5 patients' tumors were analyzed by NGS. An index case had a mono-allelic PTCH1 deletion of exons 15-24 and a second case, identified in a validation cohort, also had a PTCH1 gene loss associated with a suspected long-range chromosome 9 deletion. Building on the role of Hh signaling in PF, PTCH1, a tumor suppressor protein, functions upstream of GLI1. Loss of PTCH1 induces GLI1 activation and downstream gene transcription. Utilizing fresh tissue from the index PF case, RT-qPCR analysis demonstrated expression of Hh pathway components, SMO and GLI1, as well as GLI1 transcriptional targets, CCND1 and HHIP. In turn, short-term in vitro treatment with a Hh pathway inhibitor, sonidegib, resulted in dose-dependent cell killing.ConclusionsFor the first time, we report a novel association between PTCH1 inactivation and the development of plexiform fibromyxoma. Hh pathway inhibition with SMO antagonists may represent a target to study for treating a subset of plexiform fibromyxomas

Alginate foam-based three-dimensional culture to investigate drug sensitivity in primary leukaemia cells

The development of assays for evaluating the sensitivity of leukaemia cells to anti-cancer agents is becoming an important aspect of personalized medicine. Conventional cell cultures lack the three-dimensional (3D) structure of the bone marrow (BM), the extracellular matrix and stromal components which are crucial for the growth and survival of leukaemia stem cells. To accurately predict the sensitivity of the leukaemia cells in an in vitro assay a culturing system containing the essential components of BM is required. In this study, we developed a porous calcium alginate foam-based scaffold to be used for 3D culture. The new 3D culture was shown to be cell compatible as it supported the proliferation of both normal haematopoietic and leukaemia cells. Our cell differential assay for myeloid markers showed that the porous foam-based 3D culture enhanced myeloid differentiation in both leukaemia and normal haematopoietic cells compared to two-dimensional culture. The foam-based scaffold reduced the sensitivity of the leukaemia cells to the tested antileukaemia agents in K562 and HL60 leukaemia cell line model and also primary myeloid leukaemia cells. This observation supports the application of calcium alginate foams as scaffold components of the 3D cultures for investigation of sensitivity to antileukaemia agents in primary myeloid cells

Alterações na transmitância UV-Visível induzidas pelo uso de lentes de contacto de silicone-hidrogel

Fundação para a Ciência e a Tecnologia (FCT) through Centro de Física da U

Comparative study of silicone-hydrogel contact lenses surfaces before and after wear using atomic force microscopy

Purpose: The aim of this study was to analyze surface changes of three silicone-hydrogel contact lenses after daily wear. The lenses used in this study were balafilcon A, lotrafilcon B (both surface-treated), and galyfilcon A (non surface-treated). Methods: To understand how and where proteins, lipids, and other contaminants change contact lenses, surface roughness was assessed through Atomic Force Microscopy Tapping ModeTM. Roughness parameters were Mean Surface roughness (Ra), Mean-square-roughness (Rq), and Maximum roughness (Rmax). The surface topography of unworn and worn lenses was also mapped in great detail. Results: Contact lenses roughness parameters exhibited different values before and after wear and the surface appearance also changed. After wear, balafilcon A and galyfilcon A showed a significant increase on surface roughness parameters, being this increase more accentuated to galyfilcon A. In lotrafilcon B materials no significant changes were observed with wear. Conclusions: The present study suggests that surface treatment of silicone-hydrogel contact lenses can play a role in the prevention of a significant increase in roughness, and contribute to the better clinical tolerance of these lenses.University of PortoIBM

The influence of lens material and lens wear on the removal and viability of staphylococcus epidermidis

Purpose: The aim of this study was to evaluate the influence of lens material and lens wear on the removal capability of Staphylococcus epidermidis. Assessment of viability of remaining adhered bacteria was another goal of this work. Four silicone hydrogel materials (galyfilcon A, balafilcon A, lotrafilcon A, lotrafilcon B) and one conventional hydrogel material (etafilcon A) were assayed. Methods: Detachment studies on S. epidermidis were carried out in a parallel plate flow chamber. Contact lenses (CLs) were fitted to the bottom of the flow chamber and a bacterial suspension was perfused into the system, promoting bacterial adhesion. Afterwards, detachment was stimulated using a multipurpose solution (MPS, ReNu Multiplus®) and the percentage of removed bacteria estimated through microscopic observation and enumeration. Remaining adhered bacteria were stained with propidium iodide (PI) and enumerated in order to assess their viability. Additionally, the worn lenses were observed by confocal laser scanning microscopy (CLSM) to visualize bacterial distribution along the lens surfaces. Results: Bacterial removal was significant ( p < 0.05) for both unworn and worn galyfilcon A and etafilcon A. Galyfilcon A exhibited a detachment percentage of 59.1 and 63.5 while etafilcon A of 62.6 and 69.3, both for unworn and worn lenses, respectively. As far as bacterial viability is concerned, it was found that worn lenses exhibit a superior amount of non-viable bacteria than unworn CLs. Images obtained by CLSM revealed an irregular bacterial distribution for all lens materials. Conclusions: It appears that surface and/or bulk structure of the lens material affects removal of S. epidermidis while CL wear influences their viability.Fundação para a Ciência e a Tecnologia (FCT

The effect of silicone-hydrogel and conventional hydrogel contact lenses wear on the tear film: a comparison between de lenses

Purpose: The aim of this study was to evaluate the effect of one conventional hydrogel and four silicone-hydrogel contact lenses of 6-months daily wear on the quantity and stability of the tear film. The tests were performed with a group of patients with no previous contact lenses experience before and after wear on 96 eyes. Methods: The contact lenses tested were: 19 Galyfilcon A (Acuvue® Advance™), 15 Balafilcon A (PureVision™), 20 Lotrafilcon A (Focus® Night & Day™), 14 Lotrafilcon B (O2Optix™) and 28 Etalfilcon A (Acuvue®). Each silicone-hydrogel contact lens was used for 1 month and the conventional hydrogel for 15 days. Every patient used a different lens in each eye. Tear film stability was monitored by tear Break-up-time (BUT) and Non Invasive Break Up Time (NiBUT) and tear volume was measured by the Total Tear Meniscus Height and the Red Phenol Test. Results: The following tables summarize the difference between the measurements obtained in the first and in the last day of wear of each contact lens brand and the results were analyzed comparing the conventional hydrogel and the siliconehydrogel contact lenses (Table 1, 2, and 3), the lenses belonging to the first generation of silicone-hydrogel contact lenses (table 4) and the lenses belonging to the second generation of silicone-hydrogel (Table 5). The significance (p value) of 0.05 is considered statistically significant. Conclusions: Although there are some differences between the lenses, there are no statistically significant differences between the lenses and measurements obtained before and after contact lenses wear on the tear film tests.Objectivo: Avaliar o efeito de 6 meses de uso diário de uma lente de contacto de hidrogel convencional e quatro lentes de contacto de silicone-hidrogel na qualidade e estabilidade do filme lacrimal. Os testes foram realizados num grupo de pacientes (96 olhos) sem experiência prévia de uso de lentes de contacto, antes e depois do período de uso das lentes. Material e Métodos: As lentes de contacto estudadas foram: 19 Galyfilcon A (Acuvue® Advance™), 15 Balafilcon A (PureVision™), 20 Lotrafilcon A (Focus® Night & Day™), 14 Lotrafilcon B (O2Optix™) e 28 Etalfilcon A (Acuvue®). Cada lente de silicone-hidrogel foi usada durante 1 mês e a lente de hidrogel convencional durante 15 dias. Todos os pacientes usaram uma lente diferente em cada olho. A estabilidade do filme lacrimal foi avaliada pelo teste de ruptura lacrimal (BUT) e pelo teste de ruptura lacrimal não invasivo (NIBUT). O volume lacrimal foi medido pala altura total do menisco lacrimal e pelo teste vermelho fenol (Red Phenol Test) Resultados: Nas tabelas seguintes apresenta-se a diferença entre as medidas obtidas no 1º e último dia de uso para cada marca de lente de contacto e os resultados foram analisados comparando a lente de contacto hidrogel convencional com as lentes de silicone-hidrogel (Tabela 1, 2 e 3), as lentes pertencentes à 1ª geração de lentes de silicone-hidrogel (Tabela 4) e as lentes que pertencem à 2ª geração das lentes de silicone-hidrogel (Tabela 5). O valor da significância (p) é considerada estatisticamente significativa quando ≤0.05. Conclusões: Embora existam algumas diferenças entre as lentes de contacto estudadas, não há diferenças estatisticamente significativas entre os valores obtidos nos testes de avaliação do filme lacrimal antes e depois do uso das lentes de contacto

Attachment of a clinical strain of Staphylococcus epidermidis to worn and unworn silicone hydrogel contact lenses

Silicone hydrogel contact lenses (CL) are the newest kind of disposable lens commercially available. The copolymerization of silicone elastomers with hydrogels improves the oxygen transmissibility of silicon hydrogel CL when comparing to the conventional hydrogel CL, contributing to a better oxygen supply to the corneal tissues. However, despite this great advantage, this type of CL is usually more hydrophobic and thus is expected to be more prone to microbial colonization. The aim of this work was to study the attachment of a clinical strain of S. epidermidis (9142) to worn and unworn silicone-hydrogel CL through dynamic adhesion assays. The silicone hydrogel CL used in this study were Balafilcon A (Purevision™, Baush&Lomb), Galyfilcon A (Acuvue®Advance™ with Hydraclear, Jonhson&Jonhson Vision Care), Lotrafilcon A (Focus® Night & Day™, Ciba Vision) and Lotrafilcon B (O2Optix™, CibaVision). A conventional hydrogel Etafilcon A (Acuvue®, Jonhson&Jonhson) was also assayed. The worn CL were obtained from a group of human volunteers that used the silicone hydrogels during 1 month and the conventional hydrogel for a period of 15 days, in a daily wear schedule. The attachment assays were performed in a parallel plate flow chamber at laminar flow. The attachment experiments revealed that unworn silicone hydrogels are more prone to bacterial colonization than worn CL. Contact angle measurements, performed with Millipore water, demonstrated that after wear silicone-hydrogel CL become less hydrophobic, which may explain the decrease in the extent of bacterial adhesion to worn CL. In addition the reduction on contact angles formed on this type of lenses may be due to the adsorption of amphiphilic molecules present in the lachrymal tear film such as proteins and lipids. The conventional hydrogel Etafilcon A showed a different behaviour compared with the silicone hydrogels, concerning both hydrophobicity and bacterial attachment. This CL becomes hydrophobic after wear and exhibit an increase in bacterial colonization. This result may be due to a greater loss of the free water content enhancing the interactions between the lens surface and the bacteria

Diseño e implementación de los sistemas de control de un receptor solar volumétrico y de la etapa de potencia de una central eléctrica termosolar

XXIV JORNADAS DE AUTOMÁTICA (24) (24.2003.LEÓN, ESPAÑA)En este trabajo se muestran someramente los esquemas de control desarrollados e implementados para poder operar de forma automática una planta solar de receptor central, caracterizada porque la energía incidente no puede ser manipulada. El trabajo pretende mejorar los esquemas de control existentes hasta el momento y que se han utilizado para la operación de la planta TSA, aprovechando además la instalación de un nuevo receptor volumétrico en la planta. El trabajo se centra en la descripción los sistemas de control del flujo de aire a través de receptor y en los sistemas de control de la etapa de potencia al no disponer de resultados de operación en la actualidad porque el nuevo receptor volumétrico está en fase de instalación.Ministerio de Ciencia y Tecnología DPI2001-2380-C02Ministerio de Ciencia y Tecnología DPI2002-04375-C0