The role of D-raf in the terminal class signal transduction pathway in Drosophila melanogaster

This dissertation describes the characterization of D-raf-mediated signal transduction in the establishment and elaboration of pattern in Drosophila melanogaster. D- raf is the Drosophila homologue of the human Raf-1 proto-oncogene. As a member of the Drosophila Torso (Tor) signal transduction cascade, D-raf acts to define cellular fates at the embryonic poles. Here we show that the serine/threonine kinase activity of D-raf is required for propagation of the Tor signal and that human Raf-1 can substitute for D-raf in this pathway. We identified two serine phosphorylation sites (S388 and S743) and found that serine or its phosphorylation at site 743 is essential for D-raf function. Serine-to-alanine substitution at residue 388, amino-terminal truncation, or membrane-targeted D-raf resulted in constitutive, Tor-independent signal transduction at the embryonic poles. Membrane targeted D-raf, but not amino-terminal truncated or serine substituted D-raf (S388A), could induce the development of terminal structures in the center of embryos. Thus, localization of D-raf to the membrane appears to be an essential step in promoting Tor signal transduction in the embryonic center;We also found that maternal D-raf activation takes place between nuclear cycle 4 and 12 and zygotic expression of the D-raf gene occurs at nuclear cycle 13, 14, and blastoderm stages. Western blot analysis revealed that the accumulation of D-raf protein in embryos at 0-2 and 2-4 hours after egg laying was observed in wild-type embryos, and those derived from D-raf[superscript]400B8, D-raf[superscript] C2Z2, D-raf[superscript] DF903, D-raf[superscript] raf2, D-raf[superscript] PB26 and D-raf[superscript] DC817 but is absent from D-raf[superscript]11-29, D-raf[superscript] EA75, D-raf[superscript]107, and D-raf[superscript] raf1 mutant germlines. We also show that maternal D-raf[superscript] 400B8 and D-raf[superscript] C2Z2 proteins exhibit dominant negative effects and these effects can be surpressed by a membrane targeted D-raf. This suggests that D-raf requires interaction with its substrate(s) at a membrane associated site

Estimation of object location probability for object detection using brightness feature only

Most existing object detection methods use features such as color, shape, and contour. If there are no consistent features can be used, we need a new object detection method. Therefore, in this paper, we propose a new method for estimating the probability that an object can be located for object detection and generating an object location probability map using only brightness in a gray image. To evaluate the performance of the proposed method, we applied it to gallbladder detection. Experimental results showed 98.02% success rate for gallbladder detection in ultrasonogram. Therefore, the proposed method accurately estimates the object location probability and effectively detected gallbladder

Dumbots: Unexpected Botnets through Networked Embedded Devices

Currently, work on botnets focuses primarily on PCs. However, as lightweight computing devices with embedded operating systems become more ubiquitous, they present a new and very disturbing target for botnet developers. In this paper, we present both an empirical demonstration on a widely deployed multimedia box, as well as an evaluation of the deeper potential of these dumbots

Antibacterial Mode of Action of the Essential Oil Obtained from Chamaecyparis obtusa Sawdust on the Membrane Integrity of Selected Foodborne Pathogens

U ovom je radu ispitan mehanizam antibakterijskog učinka esencijalnog ulja dobivenog iz piljevine pačempresa (Chamaecyparis obtusa) na patogene bakterije u hrani. Esencijalno je ulje dobiveno mikrovalnom ekstrakcijom i hidrodestilacijom piljevine pačempresa. Vrijednosti su minimalne inhibitorne koncentracije esencijalnog ulja što su sprečavale rast bakterija u hrani, poput Bacillus cereus ATCC 13061, Listeria monocytogenes ATCC 7644, Staphylococcus aureus ATCC 12600, Salmonella Typhimurium ATCC 43174 i Escherichia coli ATCC 43889, bile u rasponu od 62,5 do 500 μg/mL, a vrijednosti minimalne baktericidne koncentracije u rasponu od 125 do 1000 μg/mL. Potvrđeno je da je esencijalno ulje u minimalnoj inhibitornoj koncentraciji sprečavalo rast stanica ispitanih bakerija. Osim toga, pretražnom su elektronskom mikroskopijom pronađene bitne morfološke promjene ili puknuća stanične membrane bakterija B. cereus ATCC 13061 i E. coli ATCC 43889, čime je potvrđen inhibicijski utjecaj esencijalnog ulja iz piljevine pačempresa. Oslobađanje velikih količina izvanstaničnog adenozin 5’-trifosfata (ATP) i materijala koji se apsorbira na valnoj duljini od 260 nm, te gubitak iona kalija iz stanice negativno djeluju na Gram-pozitivnu bakteriju B. cereus ATCC 13061 i Gram-negativnu bakteriju E. coli ATCC 43889, što potvrđuje učinak esencijalnog ulja na staničnu membranu. Iz dobivenih se rezultata može zaključiti da esencijalno ulje dobiveno iz piljevine pačempresa ima antibakterijsku aktivnost širokog spektra, te da djeluje na integritet stanične membrane i morfološka svojstva bakterija izoliranih iz hrane.The present study examines the possible antibacterial mechanism of action of the essential oil obtained from Chamaecyparis obtusa (COEO) sawdust against foodborne pathogenic bacteria. The COEO was obtained by microwave-assisted hydrodistillation of C. obtusa sawdust. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of COEO against the tested foodborne pathogens including Bacillus cereus ATCC 13061, Listeria monocytogenes ATCC 7644, Staphylococcus aureus ATCC 12600, Salmonella Typhimurium ATCC 43174 and Escherichia coli ATCC 43889 were found in the range from 62.5 to 500 μg/mL and from 125 to 1000 μg/mL, respectively. At the MIC concentrations, the COEO had potential inhibitory effect on the cell viability of the tested bacteria. In addition, the scanning electron microscopic analysis confirmed the inhibitory effect of COEO by revealing significant morphological alterations or rupture of the cell membranes of B. cereus ATCC 13061 and E. coli ATCC 43889. Moreover, the mode of action of COEO on the cell membrane of both Gram-positive B. cereus ATCC 13061 and Gram-negative E. coli ATCC 43889 bacteria was confirmed by marked release of extracellular adenosine 5’-triphosphate (ATP) and cellular material that absorbs at 260 nm, and by efflux of potassium ions. These findings suggest that COEO holds a broad-spectrum antibacterial efficacy, confirming its influence on the membrane integrity and morphological characteristics of tested foodborne pathogens

Vision-based Crack Identification on the Concrete Slab Surface using Fuzzy Reasoning Rules and Self-Organizing

Identifying cracks on the surface of concrete slab structure is important for structure stability maintenance. In order to avoid subjective visual inspection, it is necessary to develop an automated identification and measuring system by vision based method. Although there have been some intelligent computerized inspection methods, they are sensitive to noise due to the brightness contrast and objects such as forms and joints of certain size often falsely classified as cracks. In this paper, we propose a new fuzzy logic based image processing method that extracts cracks from concrete slab structure including small cracks that were often neglected as noise. We extract candidate crack areas by applying fuzzy method with three color channel values of concrete slab structure. Then further refinement processes are performed with Self Organizing Map algorithm and density based noise removal process to obtain basic crack characteristic attributes for further analysis. Experimental result verifies that the proposed method is sufficiently identified cracks with various sizes with high accuracy (97.3%) among 1319 ground truth cracks from 30 images

Quantitative real-time PCR method to detect changes in specific transcript and total RNA amounts

Quantitative real-time PCR (qRT-PCR), used in conjunction with reverse transcriptase, has been applied to the determination of the number of copies of a transcript per unit mass of RNA, but did not indicate any change in the amount of total RNA per mass of tissue. In the present work, we described a simple method to use qRT-PCR to estimate the change in the amount of total RNA per unit mass of wheat (Triticum aestivum L.) tissue in response to cold temperature. Three qRT-PCR templates, i.e. control, cold-exposed, and one of RNA extracted from a sample consisting of equal masses of control and cold-exposed tissue, were analyzed. The number of copies of target transcript per unit mass of RNA was estimated from the three samples using standard qRT-PCR techniques. Equations describing the number of copies of the target sequence in each of the tissue samples were solved simultaneously to describe the relative proportion of the target sequence that originated from each tissue sample in the mixture, thereby providing an estimate of relative amounts of total RNA in the two tissues

Quantitative real-time PCR method to detect changes in specific transcript and total RNA amounts

Quantitative real-time PCR (qRT-PCR), used in conjunction with reverse transcriptase, has been applied to the determination of the number of copies of a transcript per unit mass of RNA, but did not indicate any change in the amount of total RNA per mass of tissue. In the present work, we described a simple method to use qRT-PCR to estimate the change in the amount of total RNA per unit mass of wheat ( Triticum aestivum L.) tissue in response to cold temperature. Three qRT-PCR templates, i.e. control, cold-exposed, and one of RNA extracted from a sample consisting of equal masses of control and cold-exposed tissue, were analyzed. The number of copies of target transcript per unit mass of RNA was estimated from the three samples using standard qRT-PCR techniques. Equations describing the number of copies of the target sequence in each of the tissue samples were solved simultaneously to describe the relative proportion of the target sequence that originated from each tissue sample in the mixture, thereby providing an estimate of relative amounts of total RNA in the two tissues

The promoter -1031(T/C) polymorphism in tumor necrosis factor-alpha associated with polycystic ovary syndrome

<p>Abstract</p> <p>Background</p> <p>A <it>tumor necrosis factor-alpha </it>is a multifunctional pro-inflammation cytokine, which has been considered as one of pathogenic factors for various diseases. The promoter -1031(T/C) polymorphism in the <it>tumor necrosis factor-alpha </it>gene was reported that it plays a part in reproduction-related diseases. Among these, polycystic ovary syndrome (PCOS) is known to be a common gynecological disease of women in reproductive age women. Here, we performed a comparative study of -1031(T/C) polymorphism of <it>TNF-alpha </it>gene with PCOS in a Korean population.</p> <p>Methods</p> <p>The -1031(T/C) polymorphism of <it>TNF-alpha </it>gene was analyzed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) in a total of 217 PCOS patients and 144 matched female controls of healthy women. And statistical analysis was performed using HapAnalyzer. <it>X</it>²test and logistic regression were utilized analyze the association between two groups. A <it>p</it>-value under 0.05 was considered statistically significant.</p> <p>Results</p> <p>The genotype and allelic frequencies were in Hardy-Weinberg equilibrium (HWE). There was strong association between the -1031(T/C) polymorphism in the promoter region of <it>TNF-alpha </it>gene and PCOS (<it>p</it>-value = 0.0003, odd ratio (OR) = 2.53). In addition, the frequency of C allele was significantly higher in PCOS patients compared with controls. Sequence analyses also showed the -1031(T/C) polymorphism of <it>TNF-alpha </it>gene.</p> <p>Conclusion</p> <p>This is the first study on the -1031(T/C) polymorphism of <it>TNF-alpha </it>gene in PCOS. We concluded that the -1031(T/C) polymorphism of <it>TNF-alpha </it>gene is associated with PCOS in a Korean population. Therefore, it is possible that it may be considered as a clinical biomarker to diagnose for PCOS, and is helpful in understanding the etiology for the pathogenesis of PCOS.</p