430 research outputs found

    Penerapan Teknologi General Packet Radio Service Pada Sistem Monitoring Sepeda Motor

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    General Packet Radio Service (GPRS) merupakan sistem transmisi berbasis paket untuk Global System for Mobile (GSM). Pengembangan sistem keamanan menggunakan GPRS merupakan salah satu bidang yang terus mengalami pembaharuan terutama di negara Indonesia dimana keamanan masih menjadi salah satu fokus dalam perbaikan. Tingkat keamanan kendaraan terutama sepeda motor di Indonesia masih sangat kurang terjamin, hal ini menjadi latar belakang tugas akhir ini dirancang. Alat ini dirancang untuk dapat memberikan informasi tentang keberadaan sepeda motor baik dalam informasi kehilangan maupun informasi posisi kendaraan. Data mengenai informasi kehilangan akan dikirimkan langsung ke Handphone pengguna dengan transmisi GSM dan data mengenai informasi posisi berupa data lintang dan bujur akan dikirimkan menuju database yang dibuat dengan menggunakan MySQl melalui GPRS serta dapat diakses menggunakan website dengan halaman utama menggunakan HyperText Markup Language (HTML) dan koneksi dengan Google Maps API. Peta dasar yang dinamis membuat akurasi yang lebih baik antara data pelacakan dengan penandaan posisi pada peta. Data mengenai posisi akan didapat melalui Global Positioning System (GPS) yang kemudian data tersebut akan diolah menjadi data yang siap dikonversikan pada peta dan dalam bentuk sebuah marker

    Preparation of 4 '-spirocyclobutyl nucleoside analogues as novel and versatile adenosine scaffolds

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    Despite the large variety of modified nucleosides that have been reported, the preparation of constrained 4 '-spirocyclic adenosine analogues has received very little attention. We discovered that the [2+2]-cycloaddition of dichloroketene on readily available 4 '-exo-methylene furanose sugars efficiently results in the diastereoselective formation of novel 4 '-spirocyclobutanones. The reaction mechanism was investigated via density functional theory (DFT) and found to proceed either via a non-synchronous or stepwise reaction sequence, controlled by the stereochemistry at the 3 '-position of the sugar substrate. The obtained dichlorocyclobutanones were converted into nucleoside analogues, providing access to a novel class of chiral 4 '-spirocyclobutyl adenosine mimetics in eight steps from commercially available sugars. Assessment of the biological activity of designed 4 '-spirocyclic adenosine analogues identified potent inhibitors for protein methyltransferase target PRMT5

    Chronic exposure to simulated space conditions predominantly affects cytoskeleton remodeling and oxidative stress response in mouse fetal fibroblasts

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    Microgravity and cosmic rays as found in space are difficult to recreate on earth. However, ground-based models exist to simulate space flight experiments. In the present study, an experimental model was utilized to monitor gene expression changes in fetal skin fibroblasts of murine origin. Cells were continuously subjected for 65 h to a low dose. (55 mSv) of ionizing radiation (IR), comprising a mixture of high-linear energy transfer (LET) neutrons and low-LET gamma-rays, and/or simulated microgravity using the random positioning machine (RPM), after which microarrays were performed. The data were analyzed both by gene set enrichment analysis (GSEA) and single gene analysis (SGA). Simulated microgravity affected fetal murine fibroblasts by inducing oxidative stress responsive genes. Three of these genes are targets of the nuclear factor-erythroid 2 p45-related factor 2 (Nrf2), which may play a role in the cell response to simulated microgravity. In addition, simulated gravity decreased the expression of genes involved in cytoskeleton remodeling, which may have been caused by the downregulation of the serum response factor (SRF), possibly through the Rho signaling pathway. Similarly, chronic exposure to low-dose IR caused the downregulation of genes involved in cytoskeleton remodeling, as well as in cell cycle regulation and DNA damage response pathways. Many of the genes or gene sets that were altered in the individual treatments (RPM or IR) were not altered in the combined treatment (RPM and IR), indicating a complex interaction between RPM and IR

    Modulation of gene expression in endothelial cells in response to high LET nickel ion irradiation

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    Ionizing radiation can elicit harmful effects on the cardiovascular system at high doses. Endothelial cells are critical targets in radiation-induced cardiovascular damage. Astronauts performing a long-term deep space mission are exposed to consistently higher fluences of ionizing radiation that may accumulate to reach high effective doses. In addition, cosmic radiation contains high linear energy transfer (LET) radiation that is known to produce high values of relative biological effectiveness (RBE). The aim of this study was to broaden the understanding of the molecular response to high LET radiation by investigating the changes in gene expression in endothelial cells. For this purpose, a human endothelial cell line (EA.hy926) was irradiated with accelerated nickel ions (Ni) (LET, 183 keV/mu m) at doses of 0.5, 2 and 5 Gy. DNA damage was measured 2 and 24 h following irradiation by gamma-H2AX foci detection by fluorescence microscopy and gene expression changes were measured by microarrays at 8 and 24 h following irradiation. We found that exposure to accelerated nickel particles induced a persistent DNA damage response up to 24 h after treatment. This was accompanied by a downregulation in the expression of a multitude of genes involved in the regulation of the cell cycle and an upregulation in the expression of genes involved in cell cycle checkpoints. In addition, genes involved in DNA damage response, oxidative stress, apoptosis and cell-cell signaling (cytokines) were found to be upregulated. An in silico analysis of the involved genes suggested that the transcription factors, E2F and nuclear factor (NF)-kappa B, may be involved in these cellular responses

    Errors and discrepancies in the administration of intravenous infusions: a mixed methods multihospital observational study

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    Introduction Intravenous medication administration has traditionally been regarded as error prone, with high potential for harm. A recent US multisite study revealed few potentially harmful errors despite a high overall error rate. However, there is limited evidence about infusion practices in England and how they relate to prevalence and types of error. Objectives To determine the prevalence, types and severity of errors and discrepancies in infusion administration in English hospitals, and to explore sources of variation, including the contribution of smart pumps. Methods We conducted an observational point prevalence study of intravenous infusions in 16 National Health Service hospital trusts. Observers compared each infusion against the medication order and local policy. Deviations were classified as errors or discrepancies based on their potential for patient harm. Contextual issues and reasons for deviations were explored qualitatively during observer debriefs. Results Data were collected from 1326 patients and 2008 infusions. Errors were observed in 231 infusions (11.5%, 95% CI 10.2% to 13.0%). Discrepancies were observed in 1065 infusions (53.0%, 95% CI 50.8% to 55.2%). Twenty-three errors (1.1% of all infusions) were considered potentially harmful; none were judged likely to prolong hospital stay or result in long-term harm. Types and prevalence of errors and discrepancies varied widely among trusts, as did local policies. Deviations from medication orders and local policies were sometimes made for efficiency or patient need. Smart pumps, as currently implemented, had little effect, with similar error rates observed in infusions delivered with and without a smart pump (10.3% vs 10.8%, p=0.8). Conclusion Errors and discrepancies are relatively common in everyday infusion administrations but most have low potential for patient harm. Better understanding of performance variability to strategically manage risk may be a more helpful tactic than striving to eliminate all deviations

    Yeast as a Model System to Study Tau Biology

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    Hyperphosphorylated and aggregated human protein tau constitutes a hallmark of a multitude of neurodegenerative diseases called tauopathies, exemplified by Alzheimer's disease. In spite of an enormous amount of research performed on tau biology, several crucial questions concerning the mechanisms of tau toxicity remain unanswered. In this paper we will highlight some of the processes involved in tau biology and pathology, focusing on tau phosphorylation and the interplay with oxidative stress. In addition, we will introduce the development of a human tau-expressing yeast model, and discuss some crucial results obtained in this model, highlighting its potential in the elucidation of cellular processes leading to tau toxicity

    Radiation-induced alternative transcription and splicing events and their applicability to practical biodosimetry

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    Accurate assessment of the individual exposure dose based on easily accessible samples (e.g. blood) immediately following a radiological accident is crucial. We aimed at developing a robust transcription-based signature for biodosimetry from human peripheral blood mononuclear cells irradiated with different doses of X-rays (0.1 and 1.0 Gy) at a dose rate of 0.26 Gy/min. Genome-wide radiation-induced changes in mRNA expression were evaluated at both gene and exon level. Using exon-specific qRT-PCR, we confirmed that several biomarker genes are alternatively spliced or transcribed after irradiation and that different exons of these genes exhibit significantly different levels of induction. Moreover, a significant number of radiation-responsive genes were found to be genomic neighbors. Using three different classification models we found that gene and exon signatures performed equally well on dose prediction, as long as more than 10 features are included. Together, our results highlight the necessity of evaluating gene expression at the level of single exons for radiation biodosimetry in particular and transcriptional biomarker research in general. This approach is especially advisable for practical gene expression-based biodosimetry, for which primer-or probe-based techniques would be the method of choice

    Neurogranin and BACE1 in CSF as Potential Biomarkers Differentiating Depression with Cognitive Deficits from Early Alzheimer’s Disease: A Pilot Study

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    Background/Aims: Major depressive disorder (MDD) can cooccur with early Alzheimer’s disease (AD) or may cause memory problems independently of AD. Previous studies have suggested that the AD-related cerebrospinal fluid (CSF) biomarkers tau and Aβ(1–42) could help discriminate between early AD and depression unrelated to AD. Moreover, the postsynaptic protein neurogranin and presynaptic BACE1 have increasingly gained attention as potential new AD biomarkers, but they have not yet been investigated concerning depression. Methods: Using ELISAs, we studied CSF neurogranin and BACE1 levels in patients with mild (n = 21) and moderate (n = 19) AD, as well as in MDD patients with (n = 20) and without (n = 20) cognitive deficits. The clinical examinations included analyses of t-tau, Aβ(1–42), and Aβ(1–40), besides neuropsychological tests and cranial magnetic resonance imaging. Depressive symptom severity was assessed using the Geriatric Depression Scale (GDS). Results: Along with classic AD biomarkers, neurogranin and BACE1 CSF levels differed between moderate AD and MDD (p ≤ 0.01). MDD associated with cognitive deficits was distinguished from mild AD through the CSF neurogranin/BACE1 ratio (p < 0.05), which was strongly correlated with GDS scores (ρ = –0.656; p < 0.01). Conclusion: The neurogranin/BACE1 ratio in CSF can distinguish between depression and AD among patients with similar cognitive deficits, along with the classic AD biomarkers. Further longitudinal studies are ongoing to identify which biomarkers have prognostic value

    Myxoid hepatocellular adenoma, a rare variant of hepatocellular adenoma with distinct imaging features : a case report with immunohistochemical and molecular analysis and literature review

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    Preoperative imaging and histopathology, immunohistochemistry and molecular analysis after resection of 2 hepatocellular adenomas (HCAs) (20 and 2cm) in a 53-year-old female patient were performed. On imaging, the large lesion resembled a myxoid HCA, while the small lesion resembled a more conventional HCA with a small myxoid/fluid area. On microscopy, the large lesion showed cords and nests of hepatocytes embedded in abundant myxoid matrix, while the small lesion resembled a conventional HCA with small foci of myxoid change and serosities; both consistent with a myxoid HCA. Immunophenotyping and molecular subtyping excluded inflammatory HCA, CTNNB1 mutated HCA and sonic hedgehog HCA, and was consistent with HNF1A mutated HCA. The myxoid change as well as the serosities may allow imaging diagnosis of myxoid HCA. As fluid vacuoles can also be present in ASS1+HCA, sonic hedgehog HCA has to be considered in the differential diagnosis. (C) 2020 Les Auteurs. Publie par Elsevier Masson SAS
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