44 research outputs found

    Simulations of vesicular disentanglement

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    As part of the European Horizon 2020 project ACDC, a chemical compiler is being developed that allows the self-assembly of artificial, three-dimensional, vesicular structures to be first simulated and then translated into reality. This work reports on simulations that shed light on an important aspect: How to disentangle inter-vesicular connections

    ATF2 knockdown reinforces oxidative stress-induced apoptosis in TE7 cancer cells

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    Abstract Cancer cells showing low apoptotic effects following oxidative stress-induced DNA damage are mainly affected by growth arrest. Thus, recent studies focus on improving anti-cancer therapies by increasing apoptosis sensitivity. We aimed at identifying a universal molecule as potential target to enhance oxidative stress-based anti-cancer therapy through a switch from cell cycle arrest to apoptosis. A cDNA microarray was performed with hydrogen peroxide-treated oesophageal squamous epithelial cancer cells TE7. This cell line showed checkpoint activation via p21 WAF1 , but low apoptotic response following DNA damage. The potential target molecule was chosen depended on the following demands: it should regulate DNA damage response, cell cycle and apoptosis. As the transcription factor ATF2 is implicated in all these processes, we focused on this protein. We investigated checkpoint activation via ATF2. Indeed, ATF2 knockdown revealed ATF2-triggered p21 WAF1 protein expression, suggesting p21 WAF1 transactivation through ATF2. Using chromatin immunoprecipitation (ChIP), we identified a hitherto unknown ATF2-binding sequence in the p21 WAF1 promoter. p-ATF2 was found to interact with p-c-Jun, creating the AP-1 complex. Moreover, ATF2 knockdown led to c-Jun downregulation. This suggests ATF2-driven induction of c-Jun expression, thereby enhancing ATF2 transcriptional activity via c-Jun-ATF2 heterodimerization. Notably, downregulation of ATF2 caused a switch from cell cycle arrest to reinforced apoptosis, presumably via p21 WAF1 downregulation, confirming the importance of ATF2 in the establishment of cell cycle arrest. 1-Chloro-2,4-dinitrobenzene also led to ATF2-dependent G2/M arrest, suggesting that this is a general feature induced by oxidative stress. As ATF2 knockdown also increased apoptosis, we propose ATF2 as a target for combined oxidative stress-based anti-cancer therapies. Keywords: oxidative stress-induced DNA damage cell cycle arrest ATF2 knockdown increase in apoptosis sensitivities combined treatment p21 WAF

    The Role of Bile in the Regulation of Exocrine Pancreatic Secretion

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    As early as 1926 Mellanby (1) was able to show that introduction of bile into the duodenum of anesthetized cats produces a copious flow of pancreatic juice. In conscious dogs, Ivy & Lueth (2) reported, bile is only a weak stimulant of pancreatic secretion. Diversion of bile from the duodenum, however, did not influence pancreatic volume secretion stimulated by a meal (3,4). Moreover, Thomas & Crider (5) observed that bile not only failed to stimulate the secretion of pancreatic juice but also abolished the pancreatic response to intraduodenally administered peptone or soap

    Determination of nutrient salts by automatic methods both in seawater and brackish water: the phosphate blank

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    9 páginas, 2 tablas, 2 figurasThe main inconvenience in determining nutrients in seawater by automatic methods is simply solved: the preparation of a suitable blank which corrects the effect of the refractive index change on the recorded signal. Two procedures are proposed, one physical (a simple equation to estimate the effect) and the other chemical (removal of the dissolved phosphorus with ferric hydroxide).Support for this work came from CICYT (MAR88-0245 project) and Conselleria de Pesca de la Xunta de GaliciaPeer reviewe

    The Impact of a Repealed Motorcycle Helmet Law in Miami-Dade County

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    OBJECTIVE: To study the impact of helmet nonuse in motorcycle crashes after the repeal of a mandatory helmet law in the state of Florida. METHODS: We prospectively studied all patients evaluated at the University of Miami/Jackson Memorial Medical Center from July 1, 2000, through December 31, 2000, involved in motorcycle crashes, and compared them with those seen during the same time period the year before the helmet law change. RESULTS: In 1999, before the repeal of the helmet law, there were 52 cases evaluated at our center compared with 94 after the law change. Helmet usage decreased from 1999 (83%) to 2000 (56%). The number of brain injuries (Abbreviated Injury Scale score \u3e or = 2) during this same time period increased from 18 to 35, and the number of fatalities from 2 to 8. CONCLUSION: The repeal of a motorcycle helmet law significantly increased the number and severity of brain injuries admitted to our trauma center

    The Impact of a Repealed Motorcycle Helmet Law in Miami-Dade County

    No full text
    OBJECTIVE: To study the impact of helmet nonuse in motorcycle crashes after the repeal of a mandatory helmet law in the state of Florida. METHODS: We prospectively studied all patients evaluated at the University of Miami/Jackson Memorial Medical Center from July 1, 2000, through December 31, 2000, involved in motorcycle crashes, and compared them with those seen during the same time period the year before the helmet law change. RESULTS: In 1999, before the repeal of the helmet law, there were 52 cases evaluated at our center compared with 94 after the law change. Helmet usage decreased from 1999 (83%) to 2000 (56%). The number of brain injuries (Abbreviated Injury Scale score \u3e or = 2) during this same time period increased from 18 to 35, and the number of fatalities from 2 to 8. CONCLUSION: The repeal of a motorcycle helmet law significantly increased the number and severity of brain injuries admitted to our trauma center

    Automatic atlas-based segmentation of brain white matter in neonates at risk for neurodevelopmental disorders

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    Very preterm infants, < 32 weeks gestation, are at high risk for brain injury. Cognitive deficits are often diagnosed at a later stage, since there are no available predictive biomarkers in the neonatal period. The maturation of specific white matter (WM) brain structures is considered a promising early-stage biomarker. With Diffusion Tensor Imaging (DTI) tractography, an in vivo and non-invasive evaluation of these anatomical structures is possible. We developed an automatic tractography segmentation pipeline, which allows for maturation assessment of the different segmented WM structures. Our segmentation pipeline is atlas-based, specifically designed for premature neonates at term equivalent age. In order to better make use of global information from tractography, all processing is done in the fiber domain. Segmented fiber bundles are further automatically quantified with respect to volume and anisotropy. Of the 24 automatically segmented neonatal tractographies, only three contained more than 30% mislabeled fibers. Results show no dependency to WM pathology. By automatically segmenting WM, we reduced the user-dependency and bias characteristic of manual methods. This study assesses the structure of the neonatal brain based on an automatic WM segmentation in the fiber domain method using DTI tractography data
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