Risk caused by safety-critical I&C systems considerably affects overall plant risk. Software failures in digitalized I&C systems must be considered as the cause of risk. As digitalization of safety-critical systems progresses, the need for software failure probability quantification increases. For the software of safety-critical systems, very high reliability is required. This article aims at providing an overview of promising software failure probability quantification models for this kind of safety-critical system: The software reliability growth model (SRGM), the input-domain-based test model (IDBT), and the validation/verification quality model (VVQM). In order to accommodate the characteristics of safety-critical systems, a more effective framework of practical risk assessment applications is necessary. In this article, we propose the combined use of SRGM&VVQM for a more systematic and traceable method of the failure probability quantification of safety-critical software.
{"title":"Software failure probability quantification for system risk assessment","authors":"Hyun Gook Kang, H. Eom, H. Son","doi":"10.3814/2009/163456","DOIUrl":"https://doi.org/10.3814/2009/163456","url":null,"abstract":"Risk caused by safety-critical I&C systems considerably affects overall plant risk. Software failures in digitalized I&C systems must be considered as the cause of risk. As digitalization of safety-critical systems progresses, the need for software failure probability quantification increases. For the software of safety-critical systems, very high reliability is required. This article aims at providing an overview of promising software failure probability quantification models for this kind of safety-critical system: The software reliability growth model (SRGM), the input-domain-based test model (IDBT), and the validation/verification quality model (VVQM). In order to accommodate the characteristics of safety-critical systems, a more effective framework of practical risk assessment applications is necessary. In this article, we propose the combined use of SRGM&VVQM for a more systematic and traceable method of the failure probability quantification of safety-critical software.","PeriodicalId":169134,"journal":{"name":"Scholarly Research Exchange","volume":"872 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125745501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A wide-beam area X-ray source has been envisioned as capable of delivering X-ray radiation similar to a synchrotron source in terms of the magnitude of photon flux, energy range, and collimation for clinical Diffraction Enhanced Imaging (DEI) applications. Since most of the electron beam energy used to generate the X-rays is deposited in the target material as heat, a cooling system which ensures adequate thermal management is critical to the design. Previous work has shown the feasibility of a prototype scale target with heat fluxes equivalent to those envisioned for an industrial scale system. In this study, a cooling system for an industrial scale target is proposed which is capable of handling a maximum uniform heat flux of 11.693 × 10 6 W/ m 2 for a total thermal loading of 180 kW (3 Amp beam current at 60 kV accelerating voltage). The target behavior was simulated using the CFD code, ANSYS CFX. The simulation results show that target integrity can be maintained for highly non uniform heat fluxes with moderate coolant velocities and pumping powers.
{"title":"Thermal Management of Wide-Beam Area X-Ray Sources","authors":"N. A. Bobolea, J. Doster, M. Bourham","doi":"10.3814/2009/608735","DOIUrl":"https://doi.org/10.3814/2009/608735","url":null,"abstract":"A wide-beam area X-ray source has been envisioned as capable of delivering X-ray radiation similar to a synchrotron source in terms of the magnitude of photon flux, energy range, and collimation for clinical Diffraction Enhanced Imaging (DEI) applications. Since most of the electron beam energy used to generate the X-rays is deposited in the target material as heat, a cooling system which ensures adequate thermal management is critical to the design. Previous work has shown the feasibility of a prototype scale target with heat fluxes equivalent to those envisioned for an industrial scale system. In this study, a cooling system for an industrial scale target is proposed which is capable of handling a maximum uniform heat flux of 11.693 × 10 6 W/ m 2 for a total thermal loading of 180 kW (3 Amp beam current at 60 kV accelerating voltage). The target behavior was simulated using the CFD code, ANSYS CFX. The simulation results show that target integrity can be maintained for highly non uniform heat fluxes with moderate coolant velocities and pumping powers.","PeriodicalId":169134,"journal":{"name":"Scholarly Research Exchange","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116855954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The procedure of many hypotheses logarithmically asymptotically optimal (LAO) testing for a model consisting of three or more independent objects is analyzed. It is supposed that M probability distributions are known and each object follows one of them independently of others. The matrix of asymptotic interdependencies (reliability-reliability functions) of all possible pairs of the error probability exponents (reliabilities) in optimal testing for this model is studied. This problem was introduced (and solved for the case of two objects and two given probability distributions) by Ahlswede and Haroutunian; it is a generalization of two hypotheses LAO testing problem for one object investigated by Hoeffding, Csiszar and Longo, Tusnady, Longo and Sgarro, Birge, and others.
{"title":"Multiple Hypotheses LAO Testing for Many Independent Objects","authors":"E. Haroutunian, Parandzem M. Hakobyan","doi":"10.3814/2009/921574","DOIUrl":"https://doi.org/10.3814/2009/921574","url":null,"abstract":"The procedure of many hypotheses logarithmically asymptotically optimal (LAO) \u0000testing for a model consisting of three or more independent objects is analyzed. It is supposed that M probability distributions are known and each object follows one of them independently of others. The matrix of asymptotic interdependencies (reliability-reliability functions) of all possible pairs of the error probability exponents \u0000(reliabilities) in optimal testing for this model is studied. This problem was introduced (and solved for the case of two objects and two given probability distributions) by Ahlswede and Haroutunian; it is a generalization of two \u0000hypotheses LAO testing problem for one object investigated by Hoeffding, Csiszar \u0000and Longo, Tusnady, Longo and Sgarro, Birge, and others.","PeriodicalId":169134,"journal":{"name":"Scholarly Research Exchange","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132097283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. R. Jinu, P. Sathiya, G. Ravichandran, A. Rathinam
Super heater tubes are subjected to alternate heating and cooling in power plants causes crack and eventually fail. This phenomenon is termed as thermal fatigue. In this paper, a laboratory simulation for reproducing thermal fatigue phenomenon is developed to determine the number of cycles of failure occurs in super heater tubes. Thermal fatigue tests are conducted in Non-Destructive Tested T23 base and SMAW welded tubes separately. The tubes are subjected to thermal cycles from 800∘C (accelerated temperature) to room temperature (28∘C). In this work 800∘C is selected in order to achieve the crack much earlier. The selected temperature is just below the Ac 1 temperature. The tubes are subjected to heat by Oxy-acetylene flame and subsequently quenched with water. The tests are carried out until open cracks are identified. Surface cracks are identified in the base and weld tubes after 120 and 80 cycles respectively. The tubes are then sectioned and subjected to optical microscopy. The causes of failures are thoroughly investigated using Scanning Electron Microscope (SEM). This study reveals that localised heating and cooling causes thermal fatigue which initiates cracks in the tubes.
{"title":"An Experimental Study of Thermal Fatigue on ASTM A 213 Grade T-23 Steel Tube","authors":"G. R. Jinu, P. Sathiya, G. Ravichandran, A. Rathinam","doi":"10.3814/2009/309529","DOIUrl":"https://doi.org/10.3814/2009/309529","url":null,"abstract":"Super heater tubes are subjected to alternate heating and cooling \u0000in power plants causes crack and eventually fail. This phenomenon \u0000is termed as thermal fatigue. In this paper, a laboratory \u0000simulation for reproducing thermal fatigue phenomenon is developed \u0000to determine the number of cycles of failure occurs in super \u0000heater tubes. Thermal fatigue tests are conducted in \u0000Non-Destructive Tested T23 base and SMAW welded tubes separately. \u0000The tubes are subjected to thermal cycles from 800∘C (accelerated temperature) to room temperature \u0000(28∘C). In this work 800∘C is selected in order to achieve the crack much \u0000earlier. The selected temperature is just below the Ac 1 temperature. The tubes are subjected to heat by \u0000Oxy-acetylene flame and subsequently quenched with water. The \u0000tests are carried out until open cracks are identified. Surface \u0000cracks are identified in the base and weld tubes after 120 and 80 \u0000cycles respectively. The tubes are then sectioned and subjected to \u0000optical microscopy. The causes of failures are thoroughly \u0000investigated using Scanning Electron Microscope (SEM). This study \u0000reveals that localised heating and cooling causes thermal fatigue \u0000which initiates cracks in the tubes.","PeriodicalId":169134,"journal":{"name":"Scholarly Research Exchange","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128266634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Objectives. Fluconazole is an antifungal agent which has become the mainstay treatment of opportunistic fungal infections in immuno-compromized patients. Fluoxetine is a selective serotonine reuptake inhibitor used in the treatment of psychiatric disorders. In the current study we investigated the effect of chronic administration of fluoxetine on the steady state pharmacokinetics parameters of fluconazole. Methods. The pharmacokinetics of Fluconazole, following 10 mg/kg single and multiple oral dosing for 10 days, was determined in dogs. Subsequently, the effect of 2 mg/kg fluoxetine given for 10 days, on the pharmacokinetics of Fluconazole was investigated. Results. The co-administration resulted in significant reduction of 40.1% and 35.6% in AUC 0- ∞ , and C max , respectively compared to fluconazole alone. A significant alteration of V ss / F was also seen as it increased from 0.242 ± 0.04 to 0.654 ± 0.17 l/kg ( P .01 ). Accordingly, a significant reduction in K el from 0.048 ± 0.01 hr-1 to 0.031 ± 0.01 was detected ( P .01 ). Conclusion. fluoxetine reduced plasma concentration of fluconazole. The mechanism of the interaction is probably the inhibition of OATP or other transporters in the intestinal wall. This interaction may have significant clinical importance because reduction in fluconazole may lead to treatment failure of fungal infection.
{"title":"Co-administration of Fluoxetine Alters the Steady State Pharmacokinetics of Fluconazole after Multiple Oral Administration in Dogs","authors":"I. Zaghloul, Y. A. Asiri, L. Alnaim, B. Al-Hadiya","doi":"10.3814/2009/834879","DOIUrl":"https://doi.org/10.3814/2009/834879","url":null,"abstract":"Objectives. Fluconazole is an antifungal agent which has become the mainstay treatment of opportunistic fungal infections in immuno-compromized patients. Fluoxetine is a selective serotonine reuptake inhibitor used in the treatment of psychiatric disorders. In the current study we investigated the effect of chronic administration of fluoxetine on the steady state pharmacokinetics parameters of fluconazole. Methods. The pharmacokinetics of Fluconazole, following 10 mg/kg single and multiple oral dosing for 10 days, was determined in dogs. Subsequently, the effect of 2 mg/kg fluoxetine given for 10 days, on the pharmacokinetics of Fluconazole was investigated. Results. The co-administration resulted in significant reduction of 40.1% and 35.6% in AUC 0- ∞ , and C max , respectively compared to fluconazole alone. \u0000 A significant \u0000alteration of V ss / F was also seen as it increased from 0.242 ± 0.04 to 0.654 ± 0.17 l/kg ( P .01 ). Accordingly, a significant reduction \u0000in K el from 0.048 ± 0.01 hr-1 to 0.031 ± 0.01 was detected ( P .01 ). \u0000Conclusion. fluoxetine reduced plasma concentration of fluconazole. The mechanism of the interaction is probably the inhibition of OATP or other transporters in the intestinal wall. This interaction may have significant clinical importance because reduction in fluconazole may lead to treatment failure of fungal infection.","PeriodicalId":169134,"journal":{"name":"Scholarly Research Exchange","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129513803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Temperature analysis of GTA welding of Duplex Stainless Steel material (2205) is simulated using ANSYS software by finite element technique taking in account the characteristics and advantage of GTAW than other sources. A travel heat source combined with body loads was designed by analyzing thermal physical parameters, latent heat of fusion of material. Modeling was carried out by using solid modeling and direct generation technique. A residual control method was taken for precise node selection, Simulation was done by varying the parameter of GTA, welding speed. The quasisteady state temperature field of GTA welding was simulated with the FEA software—ANSYS as well as tests. The objective of this work is to compare the experimentally obtained weld bead geometry of DSS material with simulated results from ANSYS software for various weld parameters. The higher the value of joining efficiency is, the less heat energy is spent on unnecessary heating-that is generating a heat affecting zone (HAZ) or distortion. Joining of two metals or alloys is important in every aspect of engineering which leads to welding in an effective manner and carrying out the analysis. The experimental analysis shows that the model is showing good agreement with the experimental results. Comparison of the experimental and simulated results shows the maximum deviation of 1.27% and 10% for calculating bead width and depth of penetration, respectively.
{"title":"Simulation of Weld Bead Geometry in GTA Welded Duplex Stainless Steel (DSS)","authors":"P. Sathiya, G. R. Jinu, N. Singh","doi":"10.3814/2009/324572","DOIUrl":"https://doi.org/10.3814/2009/324572","url":null,"abstract":"Temperature analysis of GTA welding of Duplex Stainless Steel material (2205) is simulated using ANSYS software by finite element technique taking in account the characteristics and advantage of GTAW than other sources. A travel heat source combined with body loads was designed by analyzing thermal physical parameters, latent heat of fusion of material. Modeling was carried out by using solid modeling and direct generation technique. A residual control method was taken for precise node selection, Simulation was done by varying the parameter of GTA, welding speed. The quasisteady state temperature field of GTA welding was simulated with the FEA software—ANSYS as well as tests. The objective of this work is to compare the experimentally obtained weld bead geometry of DSS material with simulated results from ANSYS software for various weld parameters. The higher the value of joining efficiency is, the less heat energy is spent on unnecessary heating-that is generating a heat affecting zone (HAZ) or distortion. Joining of two metals or alloys is important in every aspect of engineering which leads to welding in an effective manner and carrying out the analysis. The experimental analysis shows that the model is showing good agreement with the experimental results. Comparison of the experimental and simulated results shows the maximum deviation of 1.27% and 10% for calculating bead width and depth of penetration, respectively.","PeriodicalId":169134,"journal":{"name":"Scholarly Research Exchange","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132825430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Soto, L. Ram, M. Pineda, Victor M. Gonz, P. Entringer, I. Nascimento, A. P. Souza, L. Corvo, C. Alonso, P. Bonay, C. Brodskyn, A. Barral, M. Barral-Netto, S. Iborra
Leishmaniases are a wide spectrum of parasitic diseases caused by the infection of different species of the genus Leishmania. Currently, these diseases are one of the most neglected diseases threatening 350 million people in different countries around the world. Thus, these diseases require better screening, diagnostics and treatment. An effective vaccine, that is not currently available, would be the best way to confront leishmaniases. In the past 20 years the molecular characterization of Leishmania genes encoding parasite antigens has been carried out. In this review we summarize the most common strategies employed for the isolation and characterization of genes encoding Leishmania antigens. To provide a collective view, we also discuss the results related with diagnosis and protection based on different recombinant DNA-derived Leishmania products.
{"title":"Searching genes encoding Leishmania antigens for diagnosis and protection","authors":"M. Soto, L. Ram, M. Pineda, Victor M. Gonz, P. Entringer, I. Nascimento, A. P. Souza, L. Corvo, C. Alonso, P. Bonay, C. Brodskyn, A. Barral, M. Barral-Netto, S. Iborra","doi":"10.3814/2009/173039","DOIUrl":"https://doi.org/10.3814/2009/173039","url":null,"abstract":"Leishmaniases are a wide spectrum of parasitic diseases caused by the infection of different species of the genus Leishmania. Currently, these diseases are one of the most neglected diseases threatening 350 million people in different countries around the world. Thus, these diseases require better screening, diagnostics and treatment. An effective vaccine, that is not currently available, would be the best way to confront leishmaniases. In the past 20 years the molecular characterization of Leishmania genes encoding parasite antigens has been carried out. In this review we summarize the most common strategies employed for the isolation and characterization of genes encoding Leishmania antigens. To provide a collective view, we also discuss the results related with diagnosis and protection based on different recombinant DNA-derived Leishmania products.","PeriodicalId":169134,"journal":{"name":"Scholarly Research Exchange","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132019069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Rungruangsak-Torrissen, L. Stien, Britt S. Daae, T. Vågseth, Grethe Thorsheim, D. Tobin, O. Ritola
Normal Protein (NP) and High Protein (HP) diets were provided to rainbow trout families from juvenile to maturity. Muscle protein concentration increased during growth and the protein to lipid (P/L) ratio was doubled at late stage with respect to the dietary P/L ratio. The HP-diet fish showed higher protein deposition in body and white muscle, and had lower condition factor due to protein deposition associated more with body length than body weight. Fish growth rates were decreased at maturation, and the HP-diet fish showed lower growth rate including the activity ratio of trypsin to chymotrypsin (T/C ratio) and feed efficiency. Trypsin and chymotrypsin specific activities were related to dietary protein levels, and the T/C ratio was related to intestinal weight and growth rate independent of the enzymes specific activity levels. The families with high growth capacity could double increase white muscle P/L ratio levels, compared to low and medium growth families, if they were fed on HP-diet. The digestive enzyme extracts from high growth families resulted in higher in vitro protein digestibility for all diets. The effect of dietary P/L ratio on digestion, skeletal growth (length) and the white muscle P/L ratio in fish with different growth capacities is illustrated.
{"title":"Different Dietary Levels of Protein to Lipid Ratio Affected Digestive Efficiency, Skeletal Growth, and Muscle Protein in Rainbow Trout Families","authors":"K. Rungruangsak-Torrissen, L. Stien, Britt S. Daae, T. Vågseth, Grethe Thorsheim, D. Tobin, O. Ritola","doi":"10.3814/2009/709529","DOIUrl":"https://doi.org/10.3814/2009/709529","url":null,"abstract":"Normal Protein (NP) and High Protein (HP) diets were provided to rainbow trout families from juvenile to maturity. Muscle protein concentration increased during growth and the protein to lipid (P/L) ratio was doubled at late stage with respect to the dietary P/L ratio. The HP-diet fish showed higher protein deposition in body and white muscle, and had lower condition factor due to protein deposition associated more with body length than body weight. Fish growth rates were decreased at maturation, and the HP-diet fish showed lower growth rate including the activity ratio of trypsin to chymotrypsin (T/C ratio) and feed efficiency. Trypsin and chymotrypsin specific activities were related to dietary protein levels, and the T/C ratio was related to intestinal weight and growth rate independent of the enzymes specific activity levels. The families with high growth capacity could double increase white muscle P/L ratio levels, compared to low and medium growth families, if they were fed on HP-diet. The digestive enzyme extracts from high growth families resulted in higher in vitro protein digestibility for all diets. The effect of dietary P/L ratio on digestion, skeletal growth (length) and the white muscle P/L ratio in fish with different growth capacities is illustrated.","PeriodicalId":169134,"journal":{"name":"Scholarly Research Exchange","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122804282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Mansilla, P. Lamy, T. Ørntoft, K. Birkenkamp-Demtröder
Microarray gene expression profiling comprising 168 colorectal adenocarcinomas and 10 normal mucosas showed that over 79% of the genes involved in human ribosome biogenesis are significantly upregulated ( log 2 > 0.5 , p 10 − 3 ) when compared to normal mucosa. Overexpression was independent of microsatellite status. The promoters of the genes studied showed a significant enrichment for several transcription factor binding sites. There was a significant correlation between the number of binding site targets for these transcription factors and the observed gene transcript upregulation. The upregulation of rRNA processing genes points towards a coordinated process enabling the overproduction of matured ribosomal structures.
对168例结直肠腺癌和10例正常粘膜的基因表达谱分析显示，与正常粘膜相比，超过79%参与人类核糖体生物发生的基因显著上调(log 2 > 0.5, p 10−3)。过表达与微卫星状态无关。所研究基因的启动子显示出几个转录因子结合位点的显著富集。这些转录因子结合位点靶点的数量与观察到的基因转录上调之间存在显著相关性。rRNA加工基因的上调指向一个协调的过程，使成熟核糖体结构的过量生产成为可能。
{"title":"Genes Involved in Human Ribosome Biogenesis are Transcriptionally Upregulated in Colorectal Cancer","authors":"F. Mansilla, P. Lamy, T. Ørntoft, K. Birkenkamp-Demtröder","doi":"10.3814/2009/657042","DOIUrl":"https://doi.org/10.3814/2009/657042","url":null,"abstract":"Microarray gene expression profiling comprising 168 colorectal adenocarcinomas and 10 normal mucosas showed that over 79% of the genes involved in human ribosome biogenesis are significantly upregulated ( log 2 > 0.5 , p 10 − 3 ) when compared to normal mucosa. Overexpression was independent of microsatellite status. The promoters of the genes studied showed a significant enrichment for several transcription factor binding sites. There was a significant correlation between the number of binding site targets for these transcription factors and the observed gene transcript upregulation. The upregulation of rRNA processing genes points towards a coordinated process enabling the overproduction of matured ribosomal structures.","PeriodicalId":169134,"journal":{"name":"Scholarly Research Exchange","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132782986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Morelli, G. Cafforio, S. Gallerini, M. Puglioli, A. Chiti, F. Baldacci, G. Orlandi, L. Murri, D. Guidetti
Hyperperfusion encephalopathy (HPE) is a condition due to increased perfusion of the brain which is clinically characterized by headache, seizures, and other neurologic signs associated with increased (or not) systemic blood pressures and edema in the subcortical white matter (predominantly in the occipital lobe). Patients with critical carotid stenosis treated with endarterectomy or carotid artery stenting may develop a HPE syndrome of the ipsilateral hemisphere which closely resembles the unilateral HPE and that usually involves the vascular area subjected ipsilaterally to the carotid stenosis. We present here a case of a 62-year-old woman who developed atypical hyperperfusion syndrome after a carotid stenting for high-grade carotid artery stenosis. In our patient, the HPE involved bilaterally both hemispheres, even though the treatment of the carotid stenosis was unilaterally. Some authors have hypothesized that a high dose of contrast, in combination with an unidentified personal vulnerability, may result in the rupture of the blood-brain barrier, carrying the CA into the cerebral parenchyma (both hemispheres), leading to the encephalopathy. The course and prognosis of HPE in post-carotid stenting are excellent with conservative treatment and full recovery usually occurs within 24 to 48 hours.
{"title":"Atypical Hyperperfusion Encephalopathy in Post-Carotid Stenting","authors":"N. Morelli, G. Cafforio, S. Gallerini, M. Puglioli, A. Chiti, F. Baldacci, G. Orlandi, L. Murri, D. Guidetti","doi":"10.3814/2009/108498","DOIUrl":"https://doi.org/10.3814/2009/108498","url":null,"abstract":"Hyperperfusion encephalopathy (HPE) is a condition due to \u0000increased perfusion of the brain which is clinically characterized \u0000by headache, seizures, and other neurologic signs associated with \u0000increased (or not) systemic blood pressures and edema in the \u0000subcortical white matter (predominantly in the occipital lobe). \u0000Patients with critical carotid stenosis treated with \u0000endarterectomy or carotid artery stenting may develop a HPE \u0000syndrome of the ipsilateral hemisphere which closely resembles the \u0000unilateral HPE and that usually involves the vascular area \u0000subjected ipsilaterally to the carotid stenosis. We present here a \u0000case of a 62-year-old woman who developed atypical hyperperfusion \u0000syndrome after a carotid stenting for high-grade carotid artery \u0000stenosis. In our patient, the HPE involved bilaterally both \u0000hemispheres, even though the treatment of the carotid stenosis was \u0000unilaterally. Some authors have hypothesized that a high dose of \u0000contrast, in combination with an unidentified personal \u0000vulnerability, may result in the rupture of the blood-brain \u0000barrier, carrying the CA into the cerebral parenchyma (both \u0000hemispheres), leading to the encephalopathy. The course and \u0000prognosis of HPE in post-carotid stenting are excellent with \u0000conservative treatment and full recovery usually occurs within 24 \u0000to 48 hours.","PeriodicalId":169134,"journal":{"name":"Scholarly Research Exchange","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130811637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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