Home About us Contact
|
Home About us Contact | ||
|
|
||
DS
Terms modified by DS Selected AbstractsAge-related changes in human meniscal glycosaminoglycansINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2004Gareth Blackburn Introduction With an increased human lifespan, a major challenge is now to ensure a concomitant increase in healthspan. Meniscal damage and degradation are common and are strongly correlated with subsequent osteoarthritis. Indeed, meniscal damage has been identified in about 60% of people over 60. Markers of pathology will facilitate intervention but first require normal age-related changes to be established. Methods Undamaged vascular and avascular regions of medial and lateral human menisci were comminuted and the tissue extracted into 4- m GuHCl and subject to associative CsCl density gradient centrifugation. Aggrecan and the small leucine rich PGs (SLRPs) were isolated and their GAG profiles examined by HPAEC fingerprinting, following enzyme depolymerization, and by an NMR spectroscopy. Results and discussion Analysis of aggrecan and the SLRPs show that there is a complex and dynamic pattern of KS, CS and DS abundance and distribution within human menisci, which changes with age. The abundance of SLRPs is higher in the avascular than vascular tissues, however, this is not reflected in the abundance of aggrecan which is present at similar levels in both tissue regions. The data show no other significant differences between medial and lateral and between vascular and avascular tissue regions. Analysis of the sulfation pattern of CS following digestion by ACII lyase, shows that in both aggrecan and SLRPs the 4-sulfation level falls with age from 20 to 35% in young tissues to 10,20% in older. Subsequent analyses following ABC lyase depolymerization, to include DS, shows very significant change with age from CS + DS 4-sulfation levels of ca. 40,55% in young tissue to ca. 15,30% in older. The difference between these datasets represents the contribution made by 4-sulfated DS. Thus, analysis of the difference suggests that DS makes a decreasing contribution to the CS/DS profile with age. Indeed, this is confirmed by an NMR analysis of these samples. Analysis of the resonances in the region 1.95,2.2 p.p.m. (ref to TSP) allows the estimation of the contribution made by DS, CS and KS. These data show that, in aggrecan, the contribution made by DS chains falls from ca. 10% in younger tissues to ca. 2,4% in older tissues. NMR analysis also shows that KS levels fall with age from ca. 15,20% in younger tissues to 5,10% in older tissues. Analysis of the structure of the KS chains shows chains with a structure similar to that of in articular cartilage but that at all ages there are very low levels of fucosylation (ca. 1,5%). Previous studies of age-related changes in CS/DS and KS structures have shown significant changes in the first 17 years of life, with only modest nonpathological changes after that time. These data from meniscal tissues do not show such a dramatic halting of normal age-related changes. Indeed, the data show gradual age-related changes in DS, CS and KS abundance and structure throughout life. These baseline age-related changes data will now allow the analysis of pathology-related changes. [source] Refractory Progression of Coronary Aneurysms, a Case of Delayed Onset Kawasaki Disease as Depicted by Cardiac Computed Tomography AngiographyCONGENITAL HEART DISEASE, Issue 3 2010FACP, Shah Azmoon MD ABSTRACT Background., Kawasaki disease (KD) is an immune-mediated vasculitis of unknown etiology with self-limited clinical course that was first described in 1967 by Dr. Tomisaku Kawasaki. It is a disease of early childhood and rare past late adulthood but one that can have detrimental consequences when there is a delay in diagnosis and treatment. Cardiovascular complications causing increased morbidity and mortality may include coronary artery aneurysms, myocardial infarction, heart failure, arrhythmias, and peripheral artery occlusion. Case Presentation., Here, we present an atypical case of delayed onset KD in a young teenager. DS had visited three different emergency departments during the course of 2 weeks for unrelenting fevers. Despite multiple treatment protocols including immunoglobulin, steroids, and tumor necrosis factor-alpha antagonists, he continued to have progression of cardiovascular complications. While echocardiographic findings were suspicious for cardiac complications, a cardiac computed tomography (CT) angiography was able to clearly distinguish giant coronary aneurysms. Conclusion., Without prompt therapy, fever and manifestations of acute inflammation can last for several weeks to months with increased risk toward complications. The incidence of coronary artery aneurysms has been noted to be 25% in untreated patients with a mortality rate of up to 2%. Using low-dose protocols along with high spatial and temporal resolution of cardiac CT angiography may provide a useful and complimentary imaging modality in accurate diagnosis and follow-up of patients with KD. [source] Epidemiology of Down syndromeDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 3 2007Stephanie L. Sherman Abstract Down syndrome (DS) is the most commonly identified genetic form of mental retardation and the leading cause of specific birth defects and medical conditions. Traditional epidemiological studies to determine the prevalence, cause, and clinical significance of the syndrome have been conducted over the last 100 years. DS has been estimated to occur in ,1 in 732 infants in the United States, although there is some evidence that variability in prevalence of estimates exist among racial/ethnic groups. Progress has been made in characterizing the specific types of chromosome errors that lead to DS and in identifying associated factors that increase the risk of chromosome 21 malsegregation, i.e., advanced maternal age and recombination. Studies to examine the variability of the presence of specific DS-associated birth defects and medical conditions provide evidence for genetic and environmental modifiers. Here, we provide a brief survey of studies that address the current state of the field and suggest gaps in research that can soon be filled with new multidisciplinary approaches and technological advances. © 2007 Wiley-Liss, Inc. MRDD Research Reviews 2007;13:221,227. [source] Exploring effects of different treadmill interventions on walking onset and gait patterns in infants with Down syndromeDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 11 2007Jianhua Wu PhD Two cohorts of participants were included to investigate the effects of different treadmill interventions on walking onset and gait patterns in infants with Down syndrome (DS). The first cohort included 30 infants with DS (17 males, 13 females; mean age 10mo [SD 1.9mo]) who were randomly assigned to either a lower-intensity-generalized (LG) training group, or a higher-intensity-individualized (HI) training group. A control (C) group from another study, who did not receive treadmill training, served as the control (eight males, seven females; mean age 10.4mo [SD 2.2mo]). Mean age at walking onset was 19.2, 21.4, and 23.9 months for the HI, LG, and C groups respectively. At walking onset the HI group was significantly younger than the C group (p=0.011). At the gait follow-up that was conducted between 1 and 3 months after walking onset, three groups significantly different in overall gait patterns (p=0.037) were examined by six basic gait parameters including average velocity, stride length, step width, stride time, stance time, and dynamic base. Post-hoc analyses demonstrated that stride length was the gait parameter largely contributing to this overall group difference (p=0.033), and the HI group produced a significantly longer stride length than the C group (p=0.030). In conclusion, the HI treadmill intervention significantly promoted earlier walking onset and elicited more advanced gait patterns (particularly in stride length) in infants with DS. [source] Regional analysis of bedrock stream long profiles: evaluation of Hack's SL form, and formulation and assessment of an alternative (the DS form)EARTH SURFACE PROCESSES AND LANDFORMS, Issue 5 2007Geoff Goldrick Abstract The equilibrium form of the fluvial long profile has been used to elucidate a wide range of aspects of landscape history including tectonic activity in tectonic collision zones, and in continental margin and other intraplate settings, as well as other base-level changes such as due to sealevel fluctuations. The Hack SL form of the long profile, which describes a straight line on a log,normal plot of elevation (normal) versus distance (logarithmic), is the equilibrium long profile form that has been most widely used in such studies; slope,area analysis has also been used in recent years. We show that the SL form is a special case of a more general form of the equilibrium long profile (here called the DS form) that can be derived from the power relationship between stream discharge and downstream distance, and the dependence of stream incision on stream power. The DS form provides a better fit than the SL form to river long profiles in an intraplate setting in southeastern Australia experiencing low rates of denudation and mild surface uplift. We conclude that, if an a priori form of the long profile is to be used for investigations of regional landscape history, the DS form is preferable. In particular, the DS form in principle enables equilibrium steepening due to an increase in channel substrate lithological resistance (parallel shift in the DS plot) to be distinguished from disequilibrium steepening due to long profile rejuvenation (disordered outliers on the DS plot). Slope,area analysis and the slope,distance (DS) approach outlined here are complementary approaches, reflecting the close relationship between downstream distance and downstream catchment area. Copyright © 2006 John Wiley & Sons, Ltd. [source] Evaluation of CE methods for global metabolic profiling of urineELECTROPHORESIS, Issue 14 2010Rawi Ramautar Abstract In this study, the usefulness of noncovalently coated capillaries with layers of charged polymers is investigated to obtain global electrophoretic profiles of urinary metabolites covering a broad range of different compound classes in a highly repeatable way. Capillaries were coated with a bilayer of polybrene (PB) and poly(vinyl sulfonate) (PVS), or with a triple layer of PB, dextran sulfate (DS) and PB. The bilayer and triple layer coatings were evaluated at acidic (pH 2.0) and alkaline (pH 9.0) separation conditions, thereby providing separation conditions for basic and acidic compounds. A representative metabolite mixture and spiked urine samples were used for the evaluation of the four CE methods. Migration time repeatability (RSD<2%) and plate numbers (N, 100,000,400,000) were similar for the test compounds in all CE methods, except for some multivalent ions that may exhibit adsorption to oppositely charged coatings. The analysis of cationic compounds with the PB-DS-PB CE method at low pH (i.e. after the EOF time) provided a larger separation window and number of separated peaks in urine compared to the analysis with the PB-PVS CE method at low pH (i.e. before the EOF time). Approximately, 600 molecular features were detected in rat urine by the PB-DS-PB CE-MS method whereas about 300 features were found with the PB-PVS CE-MS method. This difference can be attributed to reduced comigration of compounds with the PB-DS-PB CE-MS method and a related decrease of ion suppression. With regard to the analysis of anionic compounds by CE-MS, in general analyte responses were significantly lower than that for cationic compounds, most probably due to less efficient ionization and to ion suppression effects caused by the background electrolyte. Hence, further optimization is required for the sensitive CE-MS analysis of anionic compounds in body fluids. It is concluded that the selection of a CE method for profiling of cationic metabolites in urine depends on the purpose of the study. For high-throughput analyses, the PB-PVS CE-MS method is favored whereas the PB-DS-PB CE-MS method provides a more information-rich metabolic profile, but at the cost of prolonged analysis time. [source] Enantioseparation in capillary electrophoresis using 2- O -(2-hydroxybutyl)-,-CD as a chiral selectorELECTROPHORESIS, Issue 20 2005Xiuli Lin Abstract The resolving ability of 2- O -(2-hydroxybutyl)-,-CD (HB-,-CD) with different degrees of substitution (DS,=,2.9 and 4.0) as a chiral selector in CZE is reported in this work. Fourteen chiral drugs belonging to different classes of compounds of pharmaceutical interest such as ,-agonists, antifungal agents, ageneric agents, etc., were resolved. The effects of the DS of HB-,-CD on separations were also investigated. The chiral resolution (Rs) was strongly influenced by the concentrations of the CD derivative, the BGE, and the pH of the BGE. Under the conditions of 50,mmol/L Tris-phosphate buffer at pH,2.5 containing 5,mmol/L HB-,-CD, all 14 analytes were separated. The very low concentration necessary to obtain separation was particularly impressive. The DS had a significant effect on the resolution of the chiral drugs and the ionic strength of the separation media; hence, the use of a well-characterized CD derivative is crucial. [source] Chiral ion-exchange capillary electrochromatography of arylglycine amides with dextran sulfate as a pseudostationary phaseELECTROPHORESIS, Issue 4-5 2005Yi Chen Abstract A low-cost tunable chiral ion-exchange capillary electrochromatographic method has been developed for the separation of arylglycine amide racemic mixtures with dextran sulfate (DS) as an anionic and chiral pseudostationary phase and Tris-tartrate as a buffer system. The concentrations of DS and Tris had opposite influences on retention and resolution and could serve as ideal factors to finely tune the running speed and chiral resolution. Tartrate and pH largely impact the separation but pH should be confined within 3.0,5.5, only suitable for coarse tuning, while tartrate was preserved as the key buffering reagent, normally maintained at 40 mmol/L. With a working system composed of 0.1,1.0% DS, 20,60 mmol/L Tris, and 40 mmol/L tartrate at pH 3.50,4.50, the enantioresolution of arylglycine amides was shown to be dependent on their chemical structure: The chiral resolution increased when the hydrogen at the ,-amino group or at the p -position of phenyl ring was replaced by other larger group(s) but the resolution decreased when the group at the o- or m- site on the phenyl ring was enlarged. Further, the electronegative substitute of -Cl had larger resolution increment than methyl or methoxy at the position p- of phenyl ring but much lower increment at position m- . It is possible to well explain the resolution variation phenomenon by considering the group resistance and the variation of hydrogen-bonds formed inside the amino amides and between the solutes and DS. The amido group was shown irreplaceable to have chiral resolution with DS alone as an ionic and chiral pseudostationary phase. [source] Ultrasonic treatment of waste activated sludgeENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 2 2006Raf Dewil Abstract Activated sludge processes are key technologies to treat wastewater. These biological processes produce huge amounts of waste activated sludge (WAS), now commonly called biosolids. Mechanical, thermal, and/or chemical WAS conditioning techniques have been proposed to reduce the sludge burden. The ultrasonic treatment of WAS is quite novel. The present paper reports on extensive investigations using an ultrasonic treatment of WAS, to study its potential to meet one or all of four objectives: (1) reduce WAS quantities; (2) achieve a better dewaterability; (3) provoke a release of soluble chemical oxygen demand (COD) from the biosolids, preferably transformed into biodegradable organics; and (4) possibly destroy the filamentous microorganisms responsible for sludge bulking. Although meeting these objectives would help to solve the problems cited, the energy consumption could be a considerable drawback: the paper will thus assess whether all or some objectives are met, and at what operational cost. A literature survey defines the occurring phenomena (cavitation) and the important operation parameters [such as frequency, duration, specific energy input (SE)]. The experiments are carried out in a batch reactor of volume up to 2.3 L. The ultrasonic equipment consisted of a generator, a converter, and a sonotrode, supplied by Alpha Ultrasonics under the brand name of Telsonic. Three different kinds of sludge were tested, with different concentrations of dry solids (DS) between approximately 3.5 and 14 g DS/L WAS. Ultrasonic energy was introduced in a continuous manner (against possible pulsed operation). The major operational parameters studied include duration of the ultrasonic treatment and specific energy input. The applied frequency was set at 20 kHz. The release of COD from the WAS phase into the filtrate phase is a function of the specific energy input with yields of nearly 30% achievable at SE values of 30,000 kJ/kg DS. A major fraction of the COD is transformed into biodegradable organics (BOD). The reduction in DS fraction of the sludge is proportional to the COD release rates. Although the DS content is reduced, the dewaterability of the sludge is not improved. This reflects itself in increased filtration times during vacuum filtration and in increased values of the capillary suction time (CST). This more difficult dewaterability is the result of considerably reduced floc sizes, offering an extended surface area: more surface water is bound (CST increases) and the filterability decreases as a result of clogging of the cake. To reach the same dryness as for the untreated cake, the required dosage of polyelectrolyte is nearly doubled when the SE of the ultrasound treatment is increased from 7500 to 20,000 kJ/kg DS. The ultrasonic reduction of filamentous WAS organisms is not conclusive and very little effect is seen at low intensities and short treatment durations. Microscopic analysis of the WAS identified the dominant presence of Actynomyces. The release of soluble COD and BOD certainly merit further research. © 2006 American Institute of Chemical Engineers Environ Prog, 2006 [source] Sodium channel SCN1A and epilepsy: Mutations and mechanismsEPILEPSIA, Issue 9 2010Andrew Escayg Summary Mutations in a number of genes encoding voltage-gated sodium channels cause a variety of epilepsy syndromes in humans, including genetic (generalized) epilepsy with febrile seizures plus (GEFS+) and Dravet syndrome (DS, severe myoclonic epilepsy of infancy). Most of these mutations are in the SCN1A gene, and all are dominantly inherited. Most of the mutations that cause DS result in loss of function, whereas all of the known mutations that cause GEFS+ are missense, presumably altering channel activity. Family members with the same GEFS+ mutation often display a wide range of seizure types and severities, and at least part of this variability likely results from variation in other genes. Many different biophysical effects of SCN1A -GEFS+ mutations have been observed in heterologous expression systems, consistent with both gain and loss of channel activity. However, results from mouse models suggest that the primary effect of both GEFS+ and DS mutations is to decrease the activity of GABAergic inhibitory neurons. Decreased activity of the inhibitory circuitry is thus likely to be a major factor contributing to seizure generation in patients with GEFS+ and DS, and may be a general consequence of SCN1A mutations. [source] Symptomatic Epilepsies Imitating Idiopathic Generalized EpilepsiesEPILEPSIA, Issue 2005Hirokazu Oguni Summary:, The diagnosis of idiopathic generalized epilepsies (IGEs) is not generally difficult if one follows the clinical and electroencephalogram (EEG) definitions of each subsyndrome that constitutes IGEs. In contrast, symptomatic epilepsies develop based on organic brain lesions and are easily diagnosed by the presence of developmental delay, neurologic abnormalities, and a characteristic seizure and EEG pattern. However, in clinical practice, it is sometimes difficult to differentiate IGEs from symptomatic epilepsies, especially when the clinical course from the onset of epilepsy is too short to exhibit typical clinical and EEG findings of either epilepsy type, or when patients with symptomatic epilepsies have atypical features that imitate the clinical characteristics of IGEs. The neurodegenerative or metabolic disorders at times start during the clinical course with epileptic seizures and later show typical neurologic abnormalities. The newly recognized metabolic disorder of glucose transporter type 1 deficiency syndrome (Glut-1 DS) may start with myoclonic seizures at an age of less than 1 year and imitate benign myoclonic epilepsy in infancy early in the clinical course. Progressive myoclonus epilepsies (PMEs) that develop at 1,4 years of age at times imitate epilepsy with myoclonic-astatic seizures with respect to the presence of astatic seizures and an epileptic encephalopathic EEG pattern. In addition, young children with focal cortical dysplasia may also have similar clinical and EEG patterns, although the latter may become localized after treatment. Approximately 15% of patients with juvenile myoclonic epilepsy (JME) are resistant to antiepileptic drugs (AEDs) and may require extensive study to make a differential diagnosis from symptomatic epilepsies. PMEs that develop during adolescence may imitate JME early in the clinical course; however, a detailed history and the differentiation between myoclonic seizures and myoclonus would help to distinguish both conditions. The diagnosis of IGEs is very demanding for patients with atypical features with regard to seizure type, EEG findings, and response to appropriate AEDs. [source] Glutathione, vitamin E and oxidative stress in coronary artery disease: relevance of age and genderEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 4 2009V. Cavalca Abstract Background, Observational studies suggest that low levels of antioxidants are associated with high risk for coronary artery disease (CAD). We investigated whether the biomarkers of oxidative balance undergo the same modifications in all CAD patient groups, regardless of gender and age. Materials and methods, One hundred sixty-eight CAD patients and 107 healthy controls were assayed for plasma levels of reduced glutathione (GSH), ,- and ,-tocopherol (,- and ,-T) as endogenous antioxidants. A damage score (DS), representative of oxidative stress status, was calculated. ancova models were used to test the association between antioxidants, DS and CAD and its modulation by age and gender. Results, The DS was higher in CAD than in controls. GSH levels, were lower in CAD patients (mean ± SEM: 57·61 ± 1·87 ,mol 10 g,1 haemoglobin vs. 68·55 ± 2·23 in controls, P < 0·0006) in males and in older subjects. Levels of other antioxidants exhibited a complex pattern. Overall, no difference was found in ,- and ,-T contents between CAD and controls, but lower ,-T values were observed in CAD females. A significant interaction between CAD status and gender was observed (P = 0·003). Conclusions, Our study shows that the involvement of antioxidants in CAD is related to patients' characteristics. These findings may be relevant in planning antioxidant therapies. [source] A comparison of changes in dental students' and medical students' approaches to learning during professional trainingEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 4 2001Robert Lindemann The purposes of this study were 1) to compare the learning approaches of dental students (DS) and medical students (MS) for the Class of 1998 at a single institution at admission and graduation and 2) to determine if their learning approaches changed over the course of their studies. An Approaches to Studying Inventory (ASI) was administered to DS and MS at two times: their first month in school and their last month in school. Means and standard deviations were calculated for three ASI orientations to studying: ,Meaning', ,Reproducing', and ,Achieving'. An additional domain referred to as ,Styles and Pathologies' identified learning problems. In comparison, DS and MS demonstrated a different pattern of learning approaches at matriculation; however, at graduation these differences were less apparent. Over time, DS reported a decreased use, and MS reported an increased use of the Reproducing orientation bringing them closer together. MS also demonstrated an increased use of the Achieving orientation. The Meaning orientation, which indicates a deep approach to learning, was equivalently used by both groups at entry and remained unaltered. [source] Prevalence of disabling spasticity 1 year after first-ever strokeEUROPEAN JOURNAL OF NEUROLOGY, Issue 6 2008E. Lundström Objective:, To estimate the prevalence of disabling spasticity (DS) 1 year after first-ever stroke. Design:, Cross-sectional survey 1 year after first-ever stroke. Methods:, Patients above 18 years from one county with first-ever stroke were identified by use of the national stroke registry. A representative sample of 163 patients was created and 140 of these were followed up. Assessments of motor function and ability with the modified Ashworth Scale, the modified Rankin Scale (mRS), the Barthel Index (BI) and clinical evaluation were performed in order to identify patients with spasticity-related disability. Results:, The observed prevalence of any spasticity was 17% and of DS 4%. Patients with DS scored significantly worse than those with no DS on the mRS (P = 0.009) and the BI (P = 0.005). DS was more frequent in the upper extremity, correlated positively with other indices of motor impairment and inversely with age. There was an independent effect of severe upper extremity paresis (OR 22, CI 3.9,125) and age below 65 years (OR 9.5, CI 1.5,60). Conclusions:, The prevalence of DS after first-ever stroke is low but corresponds to a large number of patients and deserves further attention with regards to prevention and treatment. [source] The spatio-temporal and subcellular expression of the candidate Down syndrome gene Mnb/Dyrk1A in the developing mouse brain suggests distinct sequential roles in neuronal developmentEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2008Barbara Hämmerle Abstract It is widely accepted that the neurological alterations in Down syndrome (DS) are principally due to modifications in developmental processes. Accordingly, a large part of the research on DS in recent years has focused on chromosome 21 genes that influence brain development. MNB/DYRK1A is one of the genes on human chromosome 21 that has raised most interest, due to its relationship with the brain functions that are altered in DS. Although a number of interesting experimental mouse models for DS are being developed, we still know little about the expression of Mnb/Dyrk1A during mouse brain development. Here, we report that Mnb/Dyrk1A displays a rather dynamic spatio-temporal expression pattern during mouse central nervous system development. Our data indicate that Mnb/Dyrk1A is specifically expressed in four sequential developmental phases: transient expression in preneurogenic progenitors, cell cycle-regulated expression in neurogenic progenitors, transient expression in recently born neurones, and persistent expression in late differentiating neurones. Our results also suggest that the subcellular localization of MNB/DYRK1A, including its translocation to the nucleus, is finely regulated. Thus, the MNB/DYRK1A protein kinase could be a key element in the molecular machinery that couples sequential events in neuronal development. This rich repertoire of potential functions in the developing central nervous system is suitable to be linked to the neurological alterations in DS through the use of mouse experimental models. [source] A critical path method for the estimation of service restoration time in power distribution systemsEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 4 2008C. Lakshminarayana Abstract Distribution systems (DSs) are invariably subjected to various types of faults, causing power blackouts to occur. Distribution Engineers have the main responsibility to minimizing the duration of these power blackouts. This minimization can be achieved by the detailed study of pre-fault load condition of the DS, isolating the faulted section, and restoring the supply to healthy sections of the DS. Hence the estimation of service restoration time (SRT) is very important in electrical distribution systems (EDS). The estimation of SRT requires detailed knowledge of the commencement time of the emergency diesel generator (EDG) in EDS and also the operating time of the various relays in EDS. This paper introduces a new concept of optimistic time (OT), pessimistic time (PT), and most likely time (MT) of starting of the EDGs in addition to the OT, PT, and MT of the operation of the relays. The proposed concept is tested on 14-bus, 17-bus, and 29-bus distribution networks. The results reveal that it is highly suitable technique for the estimation of SRT under abnormal conditions. Hence this technique can easily be improved in distribution automation/service restoration algorithms. Copyright © 2007 John Wiley & Sons, Ltd. [source] Contact-Killing Polyelectrolyte Microcapsules Based on Chitosan DerivativesADVANCED FUNCTIONAL MATERIALS, Issue 19 2010Di Cui Abstract Polyelectrolyte-multilayer microcapsules are made by layer-by-layer (LbL) assembly of oppositely charged polyelectrolytes onto sacrificial colloidal particles, followed by core removal. In this paper, contact-killing polyelectrolyte microcapsules are prepared based solely on polysaccharides. To this end, water-soluble quaternized chitosan (QCHI) with varying degrees of substitution (DS) and hyaluronic acid (HA) are assembled into thin films. The quaternary ammonium groups are selectively grafted on the primary amine group of chitosan by exploiting its reaction with glycidyltrimethylammonium chloride (GTMAC) under homogeneous aqueous acidic conditions. The morphology of the capsules is closely dependent on the DS of the quaternized chitosan derivatives, which suggests differences in their complexation with HA. The DS is also a key parameter to control the antibacterial activity of QCHI against Escherichia Coli (E. coli). Thus, capsules containing the QCHI derivative with the highest DS are shown to be the most efficient to kill E. coli while retaining their biocompatibility toward myoblast cells, which suggests their potential as drug carriers able to combat bacterial infections. [source] Cluster headache: the challenge of clinical trials.HEADACHE, Issue 3 2003K Moore Curr Pain Headache. Rep 2002 Feb;6(1):52-56 The design and execution of clinical trials poses special problems for cluster headache. Although there is less inter-individual and intra-individual variability of attacks than seen with migraine, the brevity of attacks, spontaneous remissions unrelated to treatment, and the relative rarity of cluster headaches challenge investigators. The International Headache Society has developed guidelines that represent a compromise between scientific rigor and practicality. Only injectable sumatriptan for acute attacks and verapamil for prophylaxis have demonstrated a robust therapeutic effect in controlled clinical trials. Comment: Kenneth Moore raises important methodological considerations. It is possible to undertake crossover trials comparing different active treatments? He is correct in his assertion that few agents show robust efficacy. A major issue relates to the proportion of patients with episodic versus chronic cluster headache where efficacy of active treatments can vary. For example, oral zolmitriptan was effective against placebo only in those patients with episodic disease (Bahra A, Gawel MJ, Hardebo JE, Millson DS, Breen SA, Goadsby PJ. Oral zolmitriptan is effective in the acute treatment of cluster headache. Neurology. 2000;54:1832-1839). And a set of small studies on melatonin and cluster demonstrate the problems Dr. Moore describes. In one study (Leone M, D'Amico D, Moschiano F, Fraschini F, Busonne G. Metalonin versus placebo in the prophylaxis of cluster headache: a double-blind pilot study with parallel groups. Cephalalgia. 1996;16:494-496), the melatonin worked only in episodic, not chronic cluster patients. In the second study (Prinsheim T, Magnoux E, Dobson CF, Hamel E, Aube M. Melatonin as adjuctive therapy in the prophylaxis of cluster headache: a pilot study. Headache. 2002;42:787-792), melatonin did not work better than placebo in either episodic or chronic cluster patients. Furthermore, the paper abstracted above by Torelli and Manzoni suggests that episodic cluster may progress to chronic cluster as a result of extrinsic factors such as smoking. Finally, there are ethical issues in placebo-controlled cluster studies, given the severity of the pain and the availability of effective acute and chronic treatments. As noted above, Dr. Peter Goadsby points out the need to persevere with these studies to find nonvasoactive treatments for patients with cluster headache. DSM and SJT [source] Interaction between a chromosome 10 RET enhancer and chromosome 21 in the Down syndrome,Hirschsprung disease association,HUMAN MUTATION, Issue 5 2009Stacey Arnold Abstract Individuals with Down syndrome (DS) display a 40-fold greater risk of Hirschsprung disease (HSCR) than the general population of newborns implicating chromosome 21 in HSCR etiology. Here we demonstrate that the RET enhancer polymorphism RET+9.7 (rs2435357:C>T) at chromosome 10q11.2 is associated with HSCR in DS individuals both by transmission disequilibrium (P=0.0015) and case,control (P=0.0115) analysis of matched cases. Interestingly, the RET+9.7 T allele frequency is significantly different between individuals with DS alone (0.26±0.04), HSCR alone (0.61±0.04), and those with HSCR and DS (0.41±0.04), demonstrating an association and interaction between RET and chromosome 21 gene dosage. This is the first report of a genetic interaction between a common functional variant (rs2435357) and a not infrequent copy number error (chromosome 21 dosage) in two human developmental disorders. Hum Mutat 30:1,5, 2009. © 2009 Wiley-Liss, Inc. [source] Erratum: Detection of C1 inhibitor (SERPING1/C1NH) mutations in exon 8 in patients with hereditary angioedema: evidence for 10 novel mutations,,HUMAN MUTATION, Issue 1 2003Alvaro Blanch The original article to which this Erratum refers was published in Human Mutation 20:405,406 Human Mutation (2002) 20(5) 405,406 The authors regret that there was an error in Table 2 on Page 4 of the original article. In patient DS, the nucleotide change 16838C>T is not correct. It should be 16838G>A, since this was the mutation at the antisense change. [source] The effects of early relational antecedents and other factors on the parental sensitivity of mothers and fathersINFANT AND CHILD DEVELOPMENT, Issue 1 2003Diane Pelchat Abstract This study examines the effect of early relational antecedents (ERA, i.e. the quality of parenting parents recalled receiving as children), parenting stress, marital stress, socio-economic factors and children's characteristics (gender and disability condition) on the parental sensitivity of mothers and fathers. The sample consisted of 116 mothers and 84 fathers of 117 eighteen month old children drawn from a larger longitudinal study on the adaptation of parents to a child with a disability. Thirty-four children were diagnosed with Down syndrome (DS), 51 with a cleft lip and/or palate (CLP), and 32 were non-disabled children. Multiple regression analyses reveal that mothers' sensitivity is best predicted by her level of education and family income, whereas fathers' sensitivity is best predicted by their ERA, marital stress, family income and the child's disability condition. Mothers with more education and a greater family income displayed a greater sensitivity to their children, as did fathers who perceive less marital stress, those with a greater family income and those who perceived their parents as less controlling. Also, fathers of children with DS displayed less sensitivity for their children than fathers of children with CLP or fathers of non-disabled children. These results concord with many studies about the importance of socio-economic factors, ERA, marital stress, parent's gender and children's factors in the understanding of parental sensitivity. Copyright © 2003 John Wiley & Sons, Ltd. [source] Play and emotional availability in young children with Down syndromeINFANT MENTAL HEALTH JOURNAL, Issue 2 2008Paola Venuti This study investigates mother,child interaction and its associations with play in children with Down syndrome (DS). There is consensus that mother,child interaction during play represents an important determinant of typical children's play development. Concerning children with DS, few studies have investigated mother,child interaction in terms of the overall emotional quality of dyadic interaction and its effect on child play. A sample of 28 children with DS (M age = 3 years) took part in this study. In particular, we studied whether the presence of the mother in an interactional context affects the exploratory and symbolic play of children with DS and the interrelation between children's level of play and dyadic emotional availability. Children showed significantly more exploratory play during collaborative play with mothers than during solitary play. However, the maternal effect on child symbolic play was higher in children of highly sensitive mothers relative to children whose mothers showed lower sensitivity, the former displaying more symbolic play than the latter in collaborative play. Results offer some evidence that dyadic emotional availability and child play level are associated in children with DS, consistent with the hypothesis that dyadic interactions based on a healthy level of emotional involvement may lead to enhanced cognitive functioning. [source] Ex vivo evaluation of the accuracy and coefficient of repeatability of three electronic apex locators using a simple mounting model: a preliminary reportINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2010F. L. C. D'Assunção D'Assunção FLC, Albuquerque DS, Salazar-Silva JR, Dos Santos VC, Sousa JCN.Ex vivo evaluation of the accuracy and coefficient of repeatability of three electronic apex locators using a simple mounting model: a preliminary report. International Endodontic Journal, 43, 269,274, 2010. Abstract Aim, To compare ex vivo the accuracy and coefficient of repeatability of three electronic apex locators in locating the apical constriction. Methodology, Thirty-one single-rooted teeth were used. The teeth were sectioned at the cement,-enamel junction. A mounting model was used for the measurement of electronic length (EL). The Root ZX-II, the Mini Apex Locator and the Novapex were used for electronic measurements. Each electronic measurement was obtained and repeated. After the last measurement, the file was cemented in place, and the apical 4 mm of each root canal was exposed. The distance from the tip of the file to the apical constriction was determined by three investigators and compared with the corresponding ELs. Results, The coefficient of repeatability of all devices was acceptable: Root ZX-II, 0.04 mm; Mini Apex Locator, 0.10 mm; and Novapex, 0.08 mm. There was little variation in inter-examiner agreement; the ,C (Lin) correlation coefficient was 0.83 for examiners 1 and 2, 0.88 for examiners 1 and 3 and 0.99 for examiners 2 and 3. Using the Root ZX-II, 13 of 31 electronic measurements were located at the apical constriction (42%). Otherwise, the tip of the file was not located at the apical constriction in any of the electronic measurements with the other two devices. The Wilcoxon signed rank test did not reveal any statistical difference between the Root ZX-II measurements and the actual length (P = 0.628), but there was a statistical difference between the Mini Apex Locator and Novapex measurements and the actual length position (P < 0.05). Conclusions, The devices tested in this study had a high coefficient of repeatability. The Root ZX-II was accurate, but the Mini Apex Locator and Novapex were not accurate in locating the apical constriction. [source] Rheology of Dead Sea shampoo containing the antidandruff climbazoleINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 6 2004B. Abu-Jdayil Synopsis In this study, the effect of the antidandruff climbazole on the rheology of hair shampoo containing Dead Sea (DS) salt was investigated. The presence of either DS salt or the climbazole led to increase in the shampoo viscosity. An optimum concentration was found where the viscosity of shampoo was maximum. In the absence of DS salt, the viscosity of hair shampoo increased with increasing the climbazole concentration to reach a maximum value at 1.0 wt%. Further addition of climbazole decreased the viscosity of shampoo. Adjusting the pH of the shampoo at 5.5 and 5.0 shifted the optimum climbazole concentration (corresponds to maximum viscosity) to 0.8 wt% and led to increase in the viscosity of shampoo. On the other hand, the addition of climbazole to the shampoo containing DS salt resulted in a decrease in shampoo viscosity. This decrease of shampoo viscosity became more pronounced with increasing the climbazole and/or DS salt concentrations. By controlling the pH of shampoo, an optimum formula of shampoo comprising both climbazole and DS salt and having maximum viscosity was obtained. Résumé L'effet de l'agent antipelliculaire Climbazole sur rhéologie d'un shampooing contenant du Sel de la Mer Morte (DS) a étéétudié. La presence de DS ou de Climbazole conduit à une augmentation de la viscosité du shampooing. Une concentration optimum correspondent à la viscosité maximum du shampooing peut-être déterminée. En l'absence de DS, la viscosité du shampooing augmente avec l'augmentation en concentration du Climbazole et attaint un maximum à 1% en poids. Au delà de cette concentration, la viscosité du shampooing diminue. L'adjustement du pH du shampooing entre 5.5 et 5 induit le glissement de la concentration optimale en Climbazole (correspondent au maximum de viscosité) qui attaint alors la concentration de 0.8% enpoids et accroit encore la viscosité du shampooing. Par ailleurs, l'addition de Climbazole à un shampooing contenant du DS, provoque une diminution de la viscosité. Cette diminution s'amplifie lorsque l'on augmente la concentration en Climbazole et/ou en DS. L'adjustement du pH du Shampooing permet d'obentir une formule optimum présentant une viscosité maximum et contentant du Climbazole de du DS. [source] Rheological characterization of hair shampoo in the presence of dead sea saltINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2004B. Abu-Jdayil Synopsis In Jordan, a growing industry has been established to produce different types of Dead Sea (DS) cosmetics that have DS salt (contains mainly NaCl, KCl, and MgCl2) in their formulas. In this work, the effect of DS salt on the rheology of hair shampoo containing the sodium lauryl ether sulfate as a main active matter was studied. The effects of DS salt and active matter concentration, and the temperature and time of salt mixing, on the rheological properties of hair shampoo were investigated. The salt-free shampoo showed a Newtonian behavior at ,low active matter' (LAM) and shear thinning at ,high active matter' (HAM). The presence of DS salt changed the rheological behavior of LAM shampoo from Newtonian (for the salt-free shampoo) to shear thinning. On the other hand, the behavior of HAM shampoo switched from shear thinning to Newtonian behavior in the presence of high concentration of DS salt. The addition of DS salt increased the apparent viscosity of shampoo to reach a maximum value that corresponded to a salt concentration of 1.5 wt.%. Further addition of DS salt led to a decrease in the shampoo viscosity to reach a value less than that of the salt-free sample at high salt concentration. Changing the mixing temperature (25,45 °C) and mixing time (15,120 min) of DS salt with shampoo has no significant influence on the rheological behavior. However, the mixing process increased the apparent viscosity of salt-free shampoo. The power law model fitted well the flow curves of hair shampoo with and without DS salt. Résumé En Jordanie, une industrie croissante a été mise en place afin de produire différents types de cosmétiques à base de sels de la Mer morte (DS) contenant ces sels (pour la plupart,principalement NaCl, KCl, MgCl2) dans leurs formules. Dans ce présent travail, l'effet de ces DS sur la rhéologie d'un shampooing à base de lauryl ether sulfate de sodium comme actif principal, a étéétudié. Les effets de ce sel de DS et de la concentration en matière active ainsi que la température et le temps de mélange du sel sur les propriétés rhéologiques du shampooing ont été appréhendés. Le shampooing exempt de sel montrait un comportement Newtonien à basse concentration d'actif (LAM) et une rhéo-fluidification à haute teneur en actif (HAM). La présence de sel de DS a changé le comportement rhéologique du shampooing LAM, du Newtonien (pour le shampooing sans sel) vers la rhèo-fluidification. Par ailleurs, le comportement du shampooing HAM est passé de la rhèo-fluidification au Newtonien en présence de fortes concentrations de sels de DS. L'addition de sels de DS a accru la viscosité apparente jusqu'à une valeur maximale correspondant à 1.5% (w/w). Des additions ultérieures de sel ont conduit à une chute de la viscosité jusqu'à une valeurs inférieure à celle du shampooing sans sel. Le changement de la température de mélange du sel (25 °C à 45 °C) et du temps de mélange (15 à 120 min) du sel avec le shampooing n'a aucune influence significative sur le comportement rhéologique. Cependant, le procédé de mélange a augmenté la viscosité apparente du shampooing sans sel. La modélization par puissance a correctement ajusté les courbes d'écoulement du shampooing avec et sans sel de DS. [source] Age-related changes in human meniscal glycosaminoglycansINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2004Gareth Blackburn Introduction With an increased human lifespan, a major challenge is now to ensure a concomitant increase in healthspan. Meniscal damage and degradation are common and are strongly correlated with subsequent osteoarthritis. Indeed, meniscal damage has been identified in about 60% of people over 60. Markers of pathology will facilitate intervention but first require normal age-related changes to be established. Methods Undamaged vascular and avascular regions of medial and lateral human menisci were comminuted and the tissue extracted into 4- m GuHCl and subject to associative CsCl density gradient centrifugation. Aggrecan and the small leucine rich PGs (SLRPs) were isolated and their GAG profiles examined by HPAEC fingerprinting, following enzyme depolymerization, and by an NMR spectroscopy. Results and discussion Analysis of aggrecan and the SLRPs show that there is a complex and dynamic pattern of KS, CS and DS abundance and distribution within human menisci, which changes with age. The abundance of SLRPs is higher in the avascular than vascular tissues, however, this is not reflected in the abundance of aggrecan which is present at similar levels in both tissue regions. The data show no other significant differences between medial and lateral and between vascular and avascular tissue regions. Analysis of the sulfation pattern of CS following digestion by ACII lyase, shows that in both aggrecan and SLRPs the 4-sulfation level falls with age from 20 to 35% in young tissues to 10,20% in older. Subsequent analyses following ABC lyase depolymerization, to include DS, shows very significant change with age from CS + DS 4-sulfation levels of ca. 40,55% in young tissue to ca. 15,30% in older. The difference between these datasets represents the contribution made by 4-sulfated DS. Thus, analysis of the difference suggests that DS makes a decreasing contribution to the CS/DS profile with age. Indeed, this is confirmed by an NMR analysis of these samples. Analysis of the resonances in the region 1.95,2.2 p.p.m. (ref to TSP) allows the estimation of the contribution made by DS, CS and KS. These data show that, in aggrecan, the contribution made by DS chains falls from ca. 10% in younger tissues to ca. 2,4% in older tissues. NMR analysis also shows that KS levels fall with age from ca. 15,20% in younger tissues to 5,10% in older tissues. Analysis of the structure of the KS chains shows chains with a structure similar to that of in articular cartilage but that at all ages there are very low levels of fucosylation (ca. 1,5%). Previous studies of age-related changes in CS/DS and KS structures have shown significant changes in the first 17 years of life, with only modest nonpathological changes after that time. These data from meniscal tissues do not show such a dramatic halting of normal age-related changes. Indeed, the data show gradual age-related changes in DS, CS and KS abundance and structure throughout life. These baseline age-related changes data will now allow the analysis of pathology-related changes. [source] Purification and characterization of endocan (endothelial cell-specific molecule-1), a circulating proteoglycan involved in tumour progression and inflammatory diseasesINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2004Stéphane Sarrazin Introduction By virtue of the multiplicity of their protein-binding partners (e.g. growth factors, cytokines/chemokines), proteoglycans have been shown to be involved in the regulation of a large number of pathophysiological processes including cancer and inflammatory diseases. We have studied and characterized endocan, also called endothelial cell-specific molecule-1 (ESM-1), which represents a new group of circulating proteoglycans. Endocan is mainly expressed by endothelial cells but also by epithelial cells from lung, gut and kidney. Structurally, endocan is constituted of a mature polypeptide of 165 amino acids with a single glycosaminoglycan chain covalently linked to the serine at position 137 (Béchard et al. 2001). Methods and results We showed that human umbilical vein endothelial cells expressed endocan specifically with a single chain of dermatan sulfate (DS) as glycosaminoglycan moiety. As shown by surface plasmon resonance, the DS chain directly interacts with cytokines and growth factors including hepatocyte growth factor/scatter factor and could be responsible for endocan's biological activities. Human embryonic kidney 293 cells, which have been genetically engineered to overexpress endocan, induce tumour growth when injected subcutaneously in SCID mice. Moreover, inflammatory cytokines such as TNF-a and IL-1 have been shown to increase the synthesis and the secretion of endocan from human umbilical vein endothelial cells. Conclusion These results suggest that circulating levels of endocan may represent a novel marker for cancer and inflammatory diseases. Further studies on its GAG structure could help us to better understand the biological activities of endocan and to design future glycomic-based therapies. [source] Summarization of news video and its description for content-based accessINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 5 2003Jae-Gon Kim Abstract A video summary abstracts the entirety with the gist without losing the essential content of the original video and also facilitates efficient content-based access to the desired content. In this article, we propose a novel method for summarizing a news video based on multimodal analysis of the content. The proposed method exploits the closed caption (CC) data to locate semantically meaningful highlights in a news video and speech signals in an audio stream to align the CC data with the video in a time-line. Then, the extracted highlights are described in a multilevel structure using the MPEG-7 Summarization Description Scheme (DS). Specifically, we use the HierarchicalSummary DS that allows efficient accessing of the content through such functionalities as multilevel abstracts and navigation guidance in a hierarchical fashion. Intensive experiments with our prototypical systems are presented to demonstrate the validity and reliability of the proposed method in real applications. © 2004 Wiley Periodicals, Inc. Int J Imaging Syst Technol 13, 267,274, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10067 [source] Analysis of peripheral blood T-cell subsets, natural killer cells and serum levels of cytokines in children with Down syndromeINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 4 2010S. Cetiner Summary The objective of this study was to evaluate the relationship between humoral and cell-mediated immune response parameters and impairment of immune functions in children with Down syndrome (DS). The patient group was consisted of cytogenetically documented 32 children with DS. Lymphocyte subsets and natural killer cells were counted by flow-cytometry system. Levels of interleukin (IL)-1,, IL-2, IL-4, IL-6, IL-8, IL-10 and tumour necrosis factor-alpha (TNF-,) were detected by enzyme-linked immunosorbent assay method. Serum IgG, IgM, IgA levels were measured by turbidimetric methods. The percentage of CD8+ lymphocytes and CD56+ cells of patients with DS were significantly higher, whereas CD20+ lymphocytes were lower than that of controls (P < 0.05). The percentage of CD2 and CD4 levels and CD4/CD8 ratio of patients with DS and normal controls were similar (P > 0.05). Levels of IL-4 and IL-10 were significantly increased, but IL-6 and TNF-, levels were decreased in children with DS (P < 0.05). Levels of other studied cytokines between patients with DS and controls were not statistically different (P > 0.05, for all). Serum IgG, IgM and IgA levels were found to be similar between the groups (P > 0.05). It has been known that IL-4 and IL-10 are anti-inflammatory molecules which inhibit the synthesis of proinflammatory cytokines such as IL-6 and TNF-,. In this study, levels of IL-4 and IL-10 were significantly increased, but IL-6 and TNF-, levels were decreased in children with DS. These results may suggest that continuing anti-inflammatory state in DS and this process may explain the cause of recurrent infection of the disease. On the other hand, in contrast to the low percentage of CD20+ cells, high percentage of CD8+ and CD56+ cells were found. Our findings may demonstrate that the cell-mediated and humoral immune system parameters in children with DS were altered according to healthy children. [source] Evaluation of Common Bean for Drought Tolerance in Juana Diaz, Puerto RicoJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 5 2009T. G. Porch Abstract Drought tolerance is an increasingly important trait in common bean (Phaseolus vulgaris L.) due to the reduction in water resources, a shift in production areas and increasing input costs. The objective of this study was to evaluate 29 genotypes for drought tolerance under drought stress (DS) and reduced stress treatments in Juana Diaz, Puerto Rico. The use of DS and reduced stress treatments facilitated the identification of drought tolerant germplasm that also had good yield potential under more optimal conditions. Based on the results of seed yield under DS and reduced stress conditions, and DS indices, including the geometric mean (GM), stress tolerance index (STI) and percent yield reduction (YR), genotypes were identified with greater yield potential under the tested environment. Based on average GM over the 2 years, the superior common bean genotypes identified were SEA 5, G 21212, A 686, SEN 21 and SER 21. These genotypes performed well in both years and under both treatment conditions and thus may serve as parents for DS improvement and genetic analysis. [source] | ||||||||||||||||||||||||||||||||||||||||||||||