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Severe Conditions (severe + condition)
Selected AbstractsAbsence Epilepsy with Onset before Age Three Years: A Heterogeneous and Often Severe ConditionEPILEPSIA, Issue 7 2003Yves Chaix Summary: Purpose: The classification of epilepsies and epileptic syndromes recognizes three syndromes with typical absences [TA, i.e., childhood and juvenile absence epilepsies (CAE and JAE), and epilepsy with myoclonic absences (EMA), none of which is characterized by onset in early childhood]. Although several other forms of absence epilepsies have been described recently, none concerns infants and very young children, and little is known about the nosology and prognosis of early-onset absences. Methods: We retrospectively selected all cases with onset of absences as the only or major seizure type before age 3 years and ,2 years of follow-up among cases newly referred between 1986 and 2002. Neurospychological assessments (generally IQ measure), behavior patterns, and schooling situations were reviewed for each child. Results: We found 10 patients (7 F, 3 M). No child had sensory or motor deficits: neuroimaging was performed in nine and was normal in eight, with aspecfic findings in one. Only two could be characterized as CAE and EMA, respectively, both with seizure control and a good cognitive outcome. Among the remaining eight cases, four had a fairly homogeneous presentation with predominantly brief absences and clearly asymmetric interictal EEGs. All eight had neuropsychological and/or behavioral difficulties. Three had full seizure control, and five, persisting absences, with a follow-up ranging beetween 2 years 8 months to 9 years 4 months; only one child was older than 12 years. Conclusions: Great heterogeneity exists among absence epilepsies of early onset, which are rare conditions. Only a few patients can be categorized into well-known syndromes. The overall prognosis is poor. Early onset of absences is uncommon, and multicenter studies should help clarify the nosology and prognosis. [source] Fournier's gangrene: Report of thirty-three cases and a review of the literatureINTERNATIONAL JOURNAL OF UROLOGY, Issue 7 2006LUTFI TAHMAZ Background:, Fournier's gangrene (FG) is an extensive fulminant infection of the genitals, perineum or the abdominal wall. The aim of this study is to share our experience with the management of this difficult infectious disease. Methods:, Thirty-three male patients were admitted to our clinic with the diagnosis of FG between February 1988 and December 2003. The patient's age, etiology and predisposing factors, microbiological findings, duration of hospital stay, treatment, and outcome were analyzed. The patients were divided into two groups. The first 21 patients (Group I) were treated with broad-spectrum triple antimicrobial therapy, broad debridement, exhaustive cleaning, and then they underwent split-thickness skin grafts or delayed closure as needed. The other 12 patients (Group II) were treated with unprocessed honey (20,50 mL daily) and broad-spectrum triple antimicrobial therapy without debridement. Their wounds were cleaned with saline and then dressed with topical unprocessed honey. The wounds were inspected daily and the honey was reapplied after cleaning with normal saline. Then, the patients' scrotum and penis were covered with their own new scrotal skin. Results:, The mean age of the patients was 53.9 ± 9.56 years (range = 23,71). The source of the gangrene was urinary in 23 patients, cutaneous in seven patients, and perirectal in three patients. The predisposing factors included diabetes mellitus for 11 patients, alcoholism for 10 patients, malnutrition for nine patients, and medical immunosuppression (chemotherapy, steroids, malignancy) for three patients. The mean duration of hospital stay was 41 ± 10.459 (range = 14,54) days. Two patients in Group I died from severe sepsis. The clinical and cosmetic results were better in Group II than Group I. Conclusions:, Necrotizing fasciitis of the perineum and genitalia is a severe condition with a high morbidity and mortality. Traditionally, good management is based on aggressive debridement, broad-spectrum antibiotics, and intensive supportive care but unprocessed honey might revolutionize the treatment of this dreadful disease by reducing its cost, morbidity, and mortality. [source] DE-loop mutations affect ,2 microglobulin stability, oligomerization, and the low-pH unfolded formPROTEIN SCIENCE, Issue 7 2010Carlo Santambrogio Abstract ,2 microglobulin (,2m) is the light chain of class-I major histocompatibility complex (MHC-I). Its accumulation in the blood of patients affected by kidney failure leads to amyloid deposition around skeletal joints and bones, a severe condition known as Dialysis Related Amyloidosis (DRA). In an effort to dissect the structural determinants of ,2m aggregation, several ,2m mutants have been previously studied. Among these, three single-residue mutations in the loop connecting strands D and E (W60G, W60V, D59P) have been shown to affect ,2m amyloidogenic properties, and are here considered. To investigate the biochemical and biophysical properties of wild-type (w.t.) ,2m and the three mutants, we explored thermal unfolding by Trp fluorescence and circular dichroism (CD). The W60G mutant reveals a pronounced increase in conformational stability. Protein oligomerization and reduction kinetics were investigated by electrospray-ionization mass spectrometry (ESI-MS). All the mutations analyzed here reduce the protein propensity to form soluble oligomers, suggesting a role for the DE-loop in intermolecular interactions. A partially folded intermediate, which may be involved in protein aggregation induced by acids, accumulates for all the tested proteins at pH 2.5 under oxidizing conditions. Moreover, the kinetics of disulfide reduction reveals specific differences among the tested mutants. Thus, ,2m DE-loop mutations display long-range effects, affecting stability and structural properties of the native protein and its low-pH intermediate. The evidence presented here hints to a crucial role played by the DE-loop in determining the overall properties of native and partially folded ,2m. [source] Operation of an industrial steam reformer under severe condition: A simulation studyTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2008J. Shayegan Abstract A rigorous two-dimensional model is developed for simulating the operation of a less-investigated type steam reformer having a considerably lower operating Reynolds number, higher tube diameter, and non-availability of extra steam in the feed compared with conventional steam reformers. Simulation results show that reasonable predictions can only be achieved when certain correlations for wall to fluid heat transfer equations are applied. In all cases, strong radial temperature gradients inside the reformer tubes have been found. Furthermore, the results show how a certain catalyst loading profile will affect the operation of the reformer. Un modèle bidimensionnel rigoureux est mis au point pour simuler le fonctionnement d'un reformeur à vapeur d'un type qui a été moins étudié, ayant un nombre de Reynolds de fonctionnement bas, un diamètre de tube élevé et une non disponibilité de vapeur excédentaire dans l'alimentation comparativement aux reformeurs de vapeur classiques. Les résultats de simulation montrent que des prédictions raisonnables peuvent être obtenues seulement lorsque certaines corrélations pour les équations de transfert de chaleur de la paroi vers le fluide sont appliquées. Dans tous les cas, de forts gradients de température radiaux dans les tubes de reformeur ont été trouvés. En outre, les résultats montrent comment un certain profil de chargement de catalyseur influe le fonctionnement du reformeur. [source] MECP2 mutations in Serbian Rett syndrome patientsACTA NEUROLOGICA SCANDINAVICA, Issue 6 2007A. Djarmati Background,,, Rett syndrome is a severe neurodevelopmental X-linked dominant disorder affecting 1/15,000 girls worldwide. Eight years ago, the MECP2 gene was associated with the devastating clinical features observed in Rett syndrome patients. Objectives,,, To investigate the spectrum and the frequency of MECP2 mutations in Serbian Rett syndrome patients. Patients and methods,,, We screened the MECP2 coding region by conventional mutational screening (single-strand conformation polymorphism/sequencing) in 24 patients of Serbian origin and in their 41 unaffected family members. In search for gene dosage alterations in seemingly mutation-negative girls, we developed a new, specific quantitative PCR method. Results,,, Nineteen patients (79%) carried MECP2 mutations, five of which were novel (one nonsense mutation, one duplication and three deletions). Fourteen previously described disease-causing sequence changes and one polymorphism were also detected. Detailed case reports are given for the carriers of the novel mutations. Large MECP2 rearrangements cause Rett syndrome in a significant number of girls without ,classic' mutations in this gene. Therefore, we developed a specific quantitative PCR method, covering MECP2 exons 3 and 4, which previously has not been used for screening. No dosage alterations of the two exons were found in the four tested mutation-negative girls. Conclusions,,, This is the first genetic study of Rett syndrome in Serbian patients describing the MECP2 mutational and phenotypic spectrum in this population. Detailed clinical descriptions of this ethnically homogeneous patient population add to our knowledge of genotype/phenotype correlations in this severe condition. [source] The stratum corneum: structure and function in health and diseaseDERMATOLOGIC THERAPY, Issue 2004Clive R. Harding ABSTRACT:, Our understanding of the formation, structure, composition, and maturation of the stratum corneum (SC) has progressed enormously over the past 30 years. Today, there is a growing realization that this structure, while faithfully providing a truly magnificent barrier to water loss, is a unique, intricate biosensor that responds to environmental challenges and surface trauma by initiating a series of biologic processes which rapidly seek to repair the damage and restore barrier homeostasis. The detailed ultrastructural, biochemical, and molecular dissection of the classic "bricks and mortar" model of the SC has provided insights into the basis of dry, scaly skin disorders that range from the cosmetic problems of winter xerosis to severe conditions such as psoriasis. With this knowledge comes the promise of increasingly functional topical therapies. [source] Cognitive outcome of status epilepticus in adultsEPILEPSIA, Issue 2007Christoph Helmstaedter Summary There is no doubt that structural morphological brain lesions and malformations in epilepsy represent major etiological factors for the cognitive impairments seen in this disease. The role of epileptic activity and seizures for cognition and cognitive development, however, is less easily determined. Epileptic dysfunction ranges from interictal and periictal activity over self-terminating seizures to non-convulsive and convulsive status epilepticus, which appear the most severe conditions along this continuum. The decisive question in this regard is as to whether cognitive impairments observed in the acute epileptic condition are reversible or not. Impairments from interictal or postictal epileptic dysfunction are reversible and may interfere at most with brain maturation and cognitive development in the young patient. Seizures and ictal dysfunction in contrast, even when reversible, can leave a permanent trace which extends the phase of postictal recovery. As for status epilepticus and subsequent cognitive decline it often remains open whether the epileptic condition itself or the underlying clinical condition is causative for the aftermath. While there is evidence for both possibilities, group data from neuropsychological cross sectional and longitudinal studies indicate that more severe mental impairments, which in turn indicate more severe clinical conditions, appear to be a risk factor for sustaining status epilepticus, rather than that status epilepticus causes the cognitive decline. Reviewing the literature the cognitive condition in patients with status epilepticus varies with the type of epilepsy, the etiology of epilepsy, severity of the status, and the age of the patient. [source] Analyzing dynamic performance of stressed power systems in vicinity of instability by modal series methodEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 8 2009Ali H. Naghshbandy Abstract Highly stressed power systems exhibit complex dynamic behaviors such as inter-area oscillations when subjected to large disturbances. In such conditions, nonlinear effects have dominant role in determining dynamic response of the systems. In this paper by using modal series method, dynamic behaviors of the stressed power systems in severe conditions and near instability have been studied. Also two measures, mode dominance measure (MDM) and most perturbed machine factor (MPF) have been introduced. They determine the most dominant modes and identify the most perturbed generators when the system is subjected to a given fault. Contribution factors have been used to show the links between identified modes and machines from the analysis. Time domain simulation has been helped for validation of the results. By using similarity transformation, state variables have been represented in modal space and utilized to check the results. The studies are carried out on the IEEE 50-generator test system which demonstrates a wide range of dynamic characteristics at different loading levels and fault scenarios. Copyright © 2008 John Wiley & Sons, Ltd. [source] New data for sandwich panels on the correlation between the SBI test method and the room corner reference scenarioFIRE AND MATERIALS, Issue 1 2005Jesper Axelsson Abstract Assessment of the fire behaviour of sandwich panels is continuously under discussion. The fire behaviour of these panels is a combination of material characteristics such as the core material and mechanical behaviour of the panels such as joints, dilations etc. The use of small or intermediate scale tests can be questioned for such types of products. Within the proposed European product standard for sandwich panels (prEN 14509) the intermediate scale test method SBI (EN 13823) has been suggested as the fire test method to certify panels. The standard does, however, use quite an artificial mounting procedure, which does not fully reflect the end-use conditions of the panels. In a previous research project conducted by Nordtest it was shown that the correlation between the SBI test method and both the ISO 9705 and ISO 13784 part 1 was insufficient. The test data produced for the SBI test method, however, did not use the above mentioned mounting technique. In this article new data for a number of products are added to the database using the mounting procedure of the product standard. The data are compared with the previous data and show that the mounting method of the product standard results in slightly more severe conditions but that there are still discrepancies with the full-scale test results. The data also show an unacceptable level of repeatability due to the fact that small dilations result in a wide variation of classification result. The new data together with the old data show once more that it is dangerous to make a fire safety assessment of a sandwich panel based on small or intermediate scale tests. Copyright © 2004 John Wiley & Sons, Ltd. [source] Cola-induced hypokalaemia: pathophysiological mechanisms and clinical implicationsINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 6 2009V. Tsimihodimos Summary Background/Aims: The consumption of soft drinks has increased considerably during the last decades. Among them, the cola-based preparations are possibly the refreshments with the largest sales worldwide. In addition to the possible detrimental effects of moderate, chronic cola consumption, it has been proposed that the consumption of large amounts of cola-based soft drinks may result in severe hypokalaemia. Methods: In this review, we discuss the clinical significance of these disturbances and summarise the pathophysiological mechanism that may underlie the development of this rare, but potentially severe, side effect. Results/Conclusion: Several lines of evidence suggest that the chronic consumption of large amounts of cola soft drinks may adversely affect potassium homeostasis and result in potentially severe conditions such as hypokalaemic myopathy. [source] The effect of drying conditions on the development of the hard-to-cook defect in steam-treated cowpeasINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2006Nicole S. Affrifah Summary A three-factor,three-level Box,Behnken design was used to evaluate the effect of drying time, temperature and humidity on textural and physicochemical characteristics during storage of steamed cowpeas. The treatment significantly improved cooked texture and prevented hardening during storage under severe conditions (42 °C/80% relative humidity, RH). Before storage, the cooked texture of treated samples was between 535,628 and 602 N for the untreated control, and between 516,649 and 1394 N after storage at 42 °C/80% RH. The peak force of stored cowpeas significantly decreased as the drying temperature increased. Steaming and drying reduced phytase activity to 59,64% of the original activity and decreased phytate content from 0.133% to 0.074,0.105%. Drying time had a significant effect on phytase activity whereas all drying parameters significantly affected phytate concentration and water absorption. The drying conditions applied after steaming significantly influences seed characteristics; therefore, selection of optimum drying conditions may be used to control seed quality, especially texture. [source] Presence of furosine in honeysJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2001Mar Villamiel Abstract Nineteen commercial samples (with a shelf-life of 2 years) and two artisanal samples (freshly collected and stored for 1 year respectively) of Spanish honeys were analysed for pH, protein content and furosine content. Most of the samples had pH values and protein contents within the limits reported in the literature. The presence of furosine was confirmed by comparison of its retention time with that of a furosine standard and by HPLC,MS. The level of furosine in the samples studied ranged from 4.32 to 13.62,g,kg,1 protein. The lowest furosine value was observed in the freshly collected artisanal sample. Heat treatment under severe conditions (90,°C for up to 135,min) increased the furosine content from 4.43 to 14.38,g,kg,1 protein. The results show that furosine seems to be a promising indicator to detect overheating during honey manufacture. © 2001 Society of Chemical Industry [source] New tribometer designed for the characterisation of the friction properties at the tool/chip/workpiece interfaces in machiningLUBRICATION SCIENCE, Issue 1 2008F. Zemzemi Abstract This work deals with the development of a new tribometer designed for the characterisation of the frictional properties at the tool/chip/workpiece interfaces in cutting processes. Based on a plane,sphere contact configuration, the experimental set-up enables a continuous regeneration of the pin,workmaterial contact. The average contact pressure can be selected up to 3,GPa under sliding velocities reaching 16,m/s. Under such severe conditions, which are not reachable with conventional tribometers, the apparent friction coefficient is quantified in parallel to the heat flux transmitted to the pin. This new system has been applied to the characterisation of the frictional properties during the dry machining of a 27MnCr5 annealed steel with a carbide cutting tool. The influence of the sliding velocity and of an additional TiN layer deposited by PVD on the carbide pins has been investigated in dry conditions. It has been shown that the sliding velocity is the more influential parameter, followed by the coating. Copyright © 2007 John Wiley & Sons, Ltd. [source] A new focus on the Walther equation for lubricant viscosity determinationLUBRICATION SCIENCE, Issue 2 2006M. Sánchez-Rubio Abstract Lubricants are widely used in industrial machinery in order to separate solid tribological surfaces and support high loads under severe conditions. In tribological contacts, viscosity plays an important role in the film-forming abilities of the lubricant, but this property is strongly dependent on temperature. Consequently, small variations in temperature cause appreciable variations in the viscosity of lubricating oils. For this reason it is of practical value to be able to predict viscosity changes with temperature. This paper presents a new focus on the Walther equation to determine the viscosity of commercial lubricants at different temperatures. This new approach provides very good correlation with experimental measurements. Copyright © 2006 John Wiley & Sons, Ltd. [source] Palaeoclimate signals as inferred from stable-isotope composition of ground ice in the Verkhoyansk foreland, Central YakutiaPERMAFROST AND PERIGLACIAL PROCESSES, Issue 2 2006Steffen Popp Abstract Ice-rich permafrost deposits and their isotopic composition were studied at four sites in the western foreland of the Verkhoyansk Mountains, Central Yakutia. The isotopic composition of ice wedges formed in alluvial and loess-like sediments generally reflects the palaeoclimate of winter conditions. The middle Weichselian Ice Complex developed around 41,ka,14C BP during a period with colder winters than today. Similarly severe conditions are reflected in the late Weichselian Ice Complex from around 20,ka to 13,ka,14C BP. The transition to the Holocene is characterised by increases of 5, and 35, in ,18O and ,D, respectively. This warming is documented in wedge ice, which grew between 8.5 and 4.5,ka BP. Towards the late Holocene and sub-recent times, a climatic deterioration is recorded, reflected by lighter isotopic composition of ice wedges, which developed between 1.2,ka and 0.7,ka,14C BP. Copyright © 2006 John Wiley & Sons, Ltd. [source] Knockout of major leaf ferredoxin reveals new redox-regulatory adaptations in Arabidopsis thalianaPHYSIOLOGIA PLANTARUM, Issue 3 2008Ingo Voss Ferredoxins are the major distributors for electrons to the various acceptor systems in plastids. In green tissues, ferredoxins are reduced by photosynthetic electron flow in the light, while in heterotrophic tissues, nicotinamide adenine dinucleotide (reduced) (NADPH) generated in the oxidative pentose-phosphate pathway (OPP) is the reductant. We have used a Ds -T-DNA insertion line of Arabidopsis thaliana for the gene encoding the major leaf ferredoxin (Fd2, At1g60950) to create a situation of high electron pressure in the thylakoids. Although these plants (Fd2-KO) possess only the minor fraction of leaf Fd1 (At1g10960), they grow photoautotrophically on soil, but with a lower growth rate and less chlorophyll. The more oxidized conditions in the stroma due to the formation of reactive oxygen species are causing a re-adjustment of the redox state in these plants that helps them to survive even under high light. Redox homeostasis is achieved by regulation at both, the post-translational and the transcriptional level. Over-reduction of the electron transport chain leads to increased transcription of the malate-valve enzyme NADP-malate dehydrogenase (MDH), and the oxidized stroma leads to an increased transcription of the OPP enzyme glucose-6-P dehydrogenase. In isolated spinach chloroplasts, oxidized conditions give rise to a decreased activation state of NADP-MDH and an activation of glucose-6-P dehydrogenase even in the light. In Fd2-KO plants, NADPH-requiring antioxidant systems are upregulated. These adjustments must be caused by plastid signals, and they prevent oxidative damage under rather severe conditions. [source] Deflagration and detonation of ethylene oxide vapor in pipelinesPROCESS SAFETY PROGRESS, Issue 3 2000Paul Thibault Pure ethylene oxide (EO) vapor may propagate decomposition flames through pipe above certain minimum conditions of temperature, pressure and pipe diameter. Flame propagation was studied in both closed and vented 5 cm (2-inch) pipe and closed 30 cm (12-inch) pipe. Flame progression in closed pipe was irregular and proceeded in pulsed stages. A possible mechanism involves preferential flame propagation at the pipe roof accompanied by periodic autodecomposition of EO accumulated in hot products behind the flame front, such accumulation probably being augmented by liquid EO condensed on the pipe walls ahead of the expanding flame system. Flames propagated 15 m (50 ft) through horizontal 5 cm pipe at 70°C and initial pressures , 4.3 bar (62 psia). In a series of 30 cm pipe tests employing low-energy ignition and otherwise increasingly severe conditions, a deflagration-to-detonation transition (DDT) occurred, partially destroying the test equipment. A new test facility was set up to confirm the ability of EO to propagate detonations in 30 cm pipe and to further investigate the phenomenon. Two EO detonations at 2.9 bar and one at 3.5 bar were directly initiated via the strong shocks from hydrogen-oxygen detonations. Based on a spectrum analysis of the pressure histories, the two detonations at 2.9 bar were probably marginal and propagated in a single spin detonation mode. At 3.5 bar, the pressure history suggests that the detonation propagated in a two-head detonation mode near the end of the 24 m test section. [source] Seasonal and reproductive variation in body condition in captive female Japanese macaques (Macaca fuscata)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2010Cécile Garcia Abstract The geographic distribution of Japanese macaques includes populations with the most northern range of any primate species. Not surprisingly, females of this species are characterized by physiological adaptations and unique fat deposition mechanisms that facilitate their survival through the sometimes-harsh seasonal conditions of temperate climates, as well as sustaining the metabolic costs of mating, pregnancy, and lactation. Here, we explore the relationship between nutritional status, seasonality, and reproductive status using anthropometric and leptin measures from 14 captive female Japanese macaques. No seasonal patterns were found in the levels of leptin, but there were differences between seasons in anthropometric measures, specifically between the beginning and the end of the mating season. Females gained weight and accumulated energy reserves in fall to prepare for mating activity, and to survive the severe conditions of winter, which is also the period of gestation if pregnancy occurs. Lactating females had larger total skinfolds relative to nonlactating individuals, and females with older babies at the beginning of the mating season had larger abdominal skinfolds than did those with younger babies. There was a relationship between the likelihood of conception and nutritional status, with females that conceived during one mating season being in better condition at the end of their previous mating season. Together, these results suggest that, even in captive settings, seasonal breeding has a cost on the energetic demands of mating, and that higher condition (i.e. fatter) females could afford the demands of lactation and reproduced more rapidly. Am. J. Primatol. 72:277,286, 2010. © 2009 Wiley-Liss, Inc. [source] The Optimisation of Drying Schedules for Pinus radiata Sapwood BoardsASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 3-4 2004T.A.G. Langrish Optimal drying schedules have been predicted for the drying of Pinus radiata sapwood from an initial moisture content of 140% over a drying time of twenty-four hours for 50mm-thick boards. Initially, a single pair of dry and wet-bulb temperatures (108d,C. 60d,C) over the full time period is estimated to keep the total tangential strain under 50% of the predicted limiting failure value. However, after twelve hours drying, more severe conditions may be used, with the final moisture content predicted to be reduced from 8.2% for a constant set of conditions throughout the schedule (108d,C, 60d,C) to 2.4% when the dry-bulb temperature is raised from 108d,C to 122d,C after twelve hours. It is also possible to use a linearly increasing dry-bulb temperature after twelve hours, rising from 108d,C to 155d,C at the end of drying with a predicted final moisture content of 0.2%. However, to reduce the moisture content to only 10%, there is little difference between the ramped and two-step schedules, both yielding a total drying time of eighteen hours. The two-step schedule would be the easier to in practice. [source] | |||||||||||||||||||