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Measurement of scattering rate and minimum conductivity in graphene. PHYSICAL REVIEW LETTERS 2007; 99:246803. [PMID: 18233473 DOI: 10.1103/physrevlett.99.246803] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Indexed: 05/22/2023]
Abstract
The conductivity of graphene samples with various levels of disorder is investigated for a set of specimens with mobility in the range of 1-20x10(3) cm2/V sec. Comparing the experimental data with the theoretical transport calculations based on charged impurity scattering, we estimate that the impurity concentration in the samples varies from 2-15x10(11) cm(-2). In the low carrier density limit, the conductivity exhibits values in the range of 2-12e2/h, which can be related to the residual density induced by the inhomogeneous charge distribution in the samples. The shape of the conductivity curves indicates that high mobility samples contain some short-range disorder whereas low mobility samples are dominated by long-range scatterers.
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Abstract
The aim of this study was to evaluate the discriminant validity of the RI-48 test, a shorter French version of the Category Cued Recall portion of the Double Memory Test developed initially by Buschke and colleagues (1997), in the diagnosis of mild and very mild Alzheimer disease (AD). The distinctive feature of the RI-48 task is that encoding specificity was increased by adding an immediate cued recall stage at the encoding phase. The results show that the RI-48 task seems to be well adapted to the clinical context and to have good psychometric properties, in particular a lack of a ceiling effect. Moreover, this task appears to be especially well suited for the diagnosis of both mild and very mild AD (sensitivity of 93% and 83.8%). From a more theoretical point of view, this study confirms the importance of optimizing the encoding specificity for the diagnosis of very mild AD, since the more encoding specificity is accentuated, the more discriminating power is increased for the diagnosis of very mild AD.
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Syndrome de Gleich: à propos d'une observation. Rev Med Interne 2007. [DOI: 10.1016/j.revmed.2007.03.298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Une septicémie à Peptostreptococcus micros révélant une thrombose portale inexpliquée. Rev Med Interne 2007. [DOI: 10.1016/j.revmed.2007.03.181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Comparative study on differentiation characteristics of CD34-negative and CD34-positive human adipose tissue-derived stem cell subpopulations. J Stem Cells Regen Med 2007; 2:151. [PMID: 24692965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
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Carrier transport in two-dimensional graphene layers. PHYSICAL REVIEW LETTERS 2007; 98:186806. [PMID: 17501596 DOI: 10.1103/physrevlett.98.186806] [Citation(s) in RCA: 335] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2006] [Indexed: 05/15/2023]
Abstract
Carrier transport in gated 2D graphene monolayers is considered in the presence of scattering by random charged impurity centers with density n(i). Excellent quantitative agreement is obtained (for carrier density n>10(12) cm(-2)) with existing experimental data. The conductivity scales linearly with n/n(i) in the theory. We explain the experimentally observed asymmetry between electron and hole conductivities, and the high-density saturation of conductivity for the highest mobility samples. We argue that the experimentally observed saturation of conductivity at low density arises from the charged impurity induced inhomogeneity in the graphene carrier density which becomes severe for n less, similarn(i) approximately 10(12) cm(-2).
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Évaluer la simulation des troubles cognitifs. Rev Neurol (Paris) 2007. [DOI: 10.1016/s0035-3787(07)90901-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Abstract
Little is known about the possible link between the cognitive disorders associated with hypothyroidism and those encountered in depression. This study examines attentional and executive functions as well as the intensity of anxiety and depressive symptoms in hypothyroidism and major depression and the possible link between these symptoms and cognitive disturbances. This study confirms the existence of psychomotor slowing associated with attentional and executive disturbance in major depression as well as in hypothyroidism. However, while depressed subjects manifested a conscious bias with material of negative emotional valence, no such bias was found in the hypothyroid subjects. While the hypothyroid state is accompanied by anxiety/depressive symptoms, it seems that the latter are too discrete for an attentional bias to be observed with material with a negative emotional valence.
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The Role of Environmental and Electronic Surveillance in the Control of Invasive Aspergillosis among Ambulatory Hematologic Transplant Patients. Am J Infect Control 2006. [DOI: 10.1016/j.ajic.2006.05.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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O3-2 L’importance d’une optimisation de la spécificité d’encodage pour le diagnostic très précoce de la maladie d’Alzheimer : l’épreuve de rappel indicé à 48 items (RI-48). Rev Neurol (Paris) 2005. [DOI: 10.1016/s0035-3787(05)85304-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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O3-1 Exploration des processus inhibiteurs dans le vieillissement normal et la maladie d’Alzheimer. Rev Neurol (Paris) 2005. [DOI: 10.1016/s0035-3787(05)85303-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Anxiety and depression, attention, and executive functions in hypothyroidism. J Int Neuropsychol Soc 2005; 11:535-44. [PMID: 16212680 DOI: 10.1017/s1355617705050642] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2004] [Revised: 04/07/2005] [Accepted: 04/11/2005] [Indexed: 11/06/2022]
Abstract
BACKGROUND Divergences in cognitive disturbances in hypothyroidism reported in the literature are a result of a methodological bias. METHODS By using a precise methodology, we examined attention and executive functions in hypothyroidism, verified the presence of anxiety and depressive symptoms in hypothyroidism, and examined the possible link between these symptoms and the cognitive disturbances (searching for attentional bias for words with a negative emotional valence). We administered a battery of cognitive tests to 23 participants who had undergone thyroidectomy for thyroid carcinoma: for the first time in an euthyroid state, then 3 weeks later (still in the euthyroid state) to assess the test/retest effect, and finally 4 weeks later in an hypothyroid state. We compared their performance with that of a group of 26 control participants who were also administered the same cognitive tests, also 3 times. RESULTS In hypothyroidism, the thyroid participants were more anxious and depressed than the controls and presented attentional and executive disturbances that reflected general slowing and difficulties in using their capacities of inhibition. However, they did not exhibit an attentional bias for words with a negative emotional valence. CONCLUSIONS Contrary to what was expected, symptoms of anxiety and not symptoms of depression interfered with the cognitive performance of participants in hypothyroidism.
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The effect of nanocrystal surface structure on the luminescence properties: Photoemission study of HF-etched InP nanocrystals. J Chem Phys 2005; 123:084706. [PMID: 16164320 DOI: 10.1063/1.2004901] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
InP nanocrystals with narrow size distribution and mean particle diameter tunable from approximately 2 up to approximately 7 nm were synthesized via the dehalosilylation reaction between InCl3 and tris(trimethylsilyl)phosphine. Specific capping of the nanocrystal surface with a shell of organic ligands protects the nanocrystals from oxidation and provides solubility of the particles in various organic solvents. InP nanocrystals with enhanced photoluminescence (PL) efficiency were obtained from the initial nanocrystals by photoassisted etching of the nanocrystal surface with HF. The resulting PL quantum efficiency of InP nanocrystals dispersed in n-butanol is about three orders of magnitude higher when compared to the nonetched InP samples and approaches approximately 40% at room temperature. High-resolution photoelectron spectroscopy with the use of synchrotron radiation was applied to reveal the changes of the nanocrystal surface responsible for the dramatic improvement of the PL efficiency. The analysis of high-resolution P 2p core-level spectra confirmed significant changes of the nanocrystal surface structure induced by the postpreparative treatments and allowed us to propose the description of the etching mechanism. In the nonetched InP nanocrystals, some surface P atoms generate energy states located inside the band gap which provide nonradiative recombination pathways. Photoassisted treatment of InP nanocrystals with HF results in selective removal of these phosphorous atoms from the nanocrystal surface. The reconstructed surface of the etched InP nanocrystals is terminated mainly with In atoms and is efficiently passivated with tri-n-octylphosphine oxide ligands.
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Platform session. Surg Radiol Anat 2005. [DOI: 10.1007/bf03371475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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The value of medical student hepatitis B immunisation as part of clinical skills training in the Clinical Skills Unit of the University of the Free State. S Afr Fam Pract (2004) 2005. [DOI: 10.1080/20786204.2005.10873219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Abstract
UNLABELLED The concept of psychopathy has received many definitions for the first days of psychiatry. Recently, the Hare's Psychopathy Check List Revised has been created. This scale has the advantage to investigate the classically characteristic traits of the syndrome (need of stimulation, lack of culpability, superficial activity, lack of empathy, impassivity) and to point out the early development of behavior disturbances. In the American classification (DSM IV), oppositional and aggressive behavior in child and adolescent is grouped under the Conduct Disorder diagnostic criteria. This trouble appears to be a strong predictive factor of psychopathy in adult. Identifying the high risk factors of evolution to psychopathic personality would allow an earlier intervention and prevention by multisystemic interventions for example. The present study aims to evaluate in what measure characteristic traits of psychopathy in adults are present in severe juvenile offenders and to point out, in a second time, the differences between adolescents meeting the DSM IV criteria for Conduct Disorder and a control population by a dimensional personality inventory. METHOD The sample consists in 47 severe juvenile offenders referred for at least 3 months by a Youth Court to a Public Institution for Youth Protection (Belgium, Wauthier-Braine, 1999-2001), who have given an oral contentment and completely fulfilled the Temperament and Character Inventory-TCI. We have collected data about: schooling year by year, number of fails, changes of school; antecedents of oppositional defiant disorder with provocation (ODD, DSM IV criteria); antecedent of Conduct Disorder (CD, DSM IV criteria); penal antecedents (Youth Judge, works of general interest, placements); medico-psychological antecedents (consultation to a psychologist or a psychiatrist, hospitalization, illness, surgical intervention); psychoactive drug use or abuse. We used the TCI--Temperament and Character Inventory. This is a dimensional personality inventory. Based on biological, genetic and clinical hypothesis, it describes 2 types of variables defining personality: Variables of temperament (genetically transmitted and biologically controlled), and Variables of character (learned part of the personality reflecting the degree of adaptation and maturity, varying with environment through development). We have chosen this tool because of its dimensional aspect. Adolescence being a time of psychological and personality changes, such a tool is more useful than a categorical one. We also used this tool to verify the existence of the specific triad described by Cloninger and Svrakic. According to these authors, psychopathic personality in adult is characterized by a specific triad in which novelty seeking is high while harm avoidance and reward dependence are low. These observations are highly correlated to Hare's definition of psychopathy. We give the principal scores for the 7 personality dimensions expressed in global scores (total of the items for each dimension) and pondered ones (global scores divided by the number of items of the dimension x 100). RESULTS Statistical analysis was performed with the Stateview 5.0 t-test program for data analysis. Statistical results show the absence of a statistically significant difference between the 2 groups for TCI 1, 4.5 and 7 but a statistically significant difference for TCI 2, 3 and 6 (p <.0001). DISCUSSION The first limitation of our study is linked to the sample composed of young adolescents placed in an Institution for Youth Protection who doesn't reflect the whole population of offenders. A second limitation is correlated to the randomization system: randomization for age but not for sex, ethnical and cultural origin and socioeconomic status. Our results with adolescent offenders don't completely meet the Cloninger's psychopathy triad in adults. Moreover, in literature data, aggressive behavior is correlated to high novelty seeking and associated with low harm avoidance, reward dependence and persistence in children, these items are predictive of antisocial behavior in teenage and young adulthood. In our sample where antisocial behaviors are severe, we should be expecting a high novelty seeking but that is not the case. Our results should be explained by the fact that adolescence in itself is a more powerful factor of high novelty seeking than psychopathic trait. Harm avoidance and reward dependence seem to be a real problem in offending population and reflect aggressive behaviors in adolescents (lack of harm perception, sensitivity and empathy). Another interesting element is the cooperation factor that is significantly lower in the study group. This seems to comfort the hypothesis of a lower social maturity in institutionalized adolescents. CONCLUSION Regarding to a control group subjects from 15 to 25 years old, adolescent offenders observed in an Institution for Youth Protection show a significantly different profile in the TCI for Harm Avoidance, Reward Dependence and Cooperation. Regarding to adult psychopaths, adolescent offenders partially meet the classical diagnostic triad of psychopathy, what should be indicating that such adolescents already show emotional perturbations: lower harm avoidance, reward dependence and cooperation than control population. This third factor is not characteristic of psychopathy but reflects relational difficulties, which are important in adolescent offenders. So, our study point out the complex psychopathology of adolescent offenders and the coexistence in such adolescents of attachment disorder and the difficulty to treat them because of their multiple lacks (cognitive, psychopathological, familial and scholar). We think important to discuss the necessity of approaches based on the development of personal creative abilities and involving all the professionals concerned in the young's universe. Future researches should compare adolescent offenders and controls randomized for age, sex, socioeconomic, ethnical and cultural status. They also should test specifically the diagnostic triad of psychopathology developed by Cloninger, especially the novelty seeking dimension. Moreover, it would be interesting to integrate these results in a wider protocol and to compare them with clinical, forensic and neurocognitive data, individually and within the familial context.
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Cerebral metabolic correlates of four dementia scales in Alzheimer's disease. J Neurol 2005; 252:283-90. [PMID: 16189724 DOI: 10.1007/s00415-005-0551-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2003] [Revised: 03/09/2004] [Accepted: 05/10/2004] [Indexed: 10/25/2022]
Abstract
Different scales can be used to evaluate dementia severity in Alzheimer's disease (AD). They do assess different cognitive or functional abilities, but their global scores are frequently in mutual correlation. Functional imaging provides an objective method for the staging of dementia severity. Positron emission tomography was used to assess the relationship between brain metabolism and four dementia scales that reflect a patient's global cognitive abilities (mini mental state), caregiver's evaluation of cognitive impairment (newly designed scale), daily living functioning (instrumental activities of daily living) and global dementia (clinical dementia rating). We wondered whether different clinical dementia scales would be related to severity of metabolic impairment in the same brain regions, and might reflect impairment of common cognitive processes. 225 patients with probable AD were recruited in a prospective multicentre European study. All clinical scales were related to brain metabolism in associative temporal, parietal or frontal areas. A factorial analysis demonstrated that all scales could be classified in a single factor. That factor was highly correlated to decrease of cerebral activity in bilateral parietal and temporal cortices, precuneus, and left middle frontal gyrus. This finding suggests that global scores for all scales provided similar information on the neural substrate of dementia severity. Capitalizing on the neuroimaging literature, dementia severity reflected by reduced metabolism in posterior and frontal associative areas in AD might be related to a decrease of controlled processes.
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Anwendung der dekompressiven Kraniektomie als Behandlungsalternative bei erhöhtem intrakraniellen Druck:. Anasthesiol Intensivmed Notfallmed Schmerzther 2004. [DOI: 10.1055/s-1999-10836-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Vergleich der Biokompatibilität verschiedener Filtermembranen anhand des Thrombin-Antithrombin (TAT)-Komplexes*. Anasthesiol Intensivmed Notfallmed Schmerzther 2004. [DOI: 10.1055/s-2000-10846-19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Trouble spécifique à une catégorie : le rôle de la sémantique de l’action. Rev Neurol (Paris) 2004. [DOI: 10.1016/s0035-3787(04)70977-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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126
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Development of the embryonal and foetal liver: morphology and morphometry from ductal plate to interlobular bile duct. Pathol Res Pract 2004. [DOI: 10.1016/s0344-0338(04)80795-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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High resolution photoemission study of CdSe and CdSe/ZnS core-shell nanocrystals. J Chem Phys 2003. [DOI: 10.1063/1.1580096] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Abstract
BACKGROUND AND AIMS Nutritional assessment enhances quality of nutritional care, however, its practice bemuses professionals. This prospective study aimed to identify a feasible/informative nutritional parameter in intensive care. METHODS 44 patients (APACHE II: 23.8+/-10.1), age 58.4+/-18.6 years, were evaluated at admission: clinical data, height, weight, body mass index (BMI), tricep skinfold thickness, mid-arm circumference (MAC), mid-arm muscle circumference (MAMC), albumin, total protein and lymphocyte count. Anthropometric parameters' performance was evaluated isolated or assembled according to Blackburn and McWhirter criteria. RESULTS Oedema increased %IW and BMI (P<0.01); muscle depletion was frequent and agreed with MAC or MAMC ranked by both criteria, P=0.02. %IW and BMI overestimated well-nourished/overweight patients, whilst arm anthropometry, mostly MAC/MAMC, shifted towards +/-50% malnutrition. Patients were not equally ranked by both criteria; McWhirter's by using percentiles clarified the distribution and showed agreement between MAC and MAMC, P=0.007, unlike Blackburn's. Mortality was higher in patients with MAC<5th percentile, P=0.003; MAC;<15th percentile was able to predict mortality and major complications. In invasive ventilated patients, severe muscle depletion was associated with mortality, P=0.05. CONCLUSION In intensive care most nutritional assessment methods are useless; MAC is simple, feasible and if classified by percentiles may prove functional with prognostic value.
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Diastereoselective alkylation of 2,3,4,6-Di-O-isopropylidene-2-keto-L-gulonic amides. Application to the asymmetric synthesis of 1-substituted-1,2,3,4-tetrahydroisoquinolines and 1-substituted-1,2,3,4,-tetrahydro-beta-carbolines. J Org Chem 2001; 66:8744-50. [PMID: 11749602 DOI: 10.1021/jo0155658] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The diastereoselective alkylation of amides 3a,b and 7a,b derived from gulonic acid is described. Substituted compounds are obtained in good yield and high diastereoselectivity. A mechanistic investigation establishes that the diastereoselectivity did not arise from an initial asymmetric deprotonation. The stereochemistry is then determined during the alkylation step.
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Mapping a method for systematically reviewing the medical literature: a helpful checklist postmortem protocol of human immunodeficiency virus (HIV)-related pathology in childhood. Pathologica 2001; 93:201-7. [PMID: 11433613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
INTRODUCTION Since the first description of two children affected with human immunodeficiency virus (HIV), various diagnostic procedures have been established. However, the morphologic study of biopsy and autopsy material from children with acquired immunodeficiency syndrome (AIDS) is still of fundamental importance. The morphology has contributed remarkably to the progress in understanding the pathogenesis of the primary tissue lesions and of the sequelae directly or indirectly associated with HIV infection. The aim of this study was to evaluate the HIV pathology in pediatric AIDS (PAIDS) through a systematic review of the English-language literature and to draw up a practical checklist protocol for the postmortem. MATERIALS AND METHODS Information on HIV pathology in childhood was retrieved from a MEDLINE search (January 1994-January 2001) of the original reports and bibliographic article reviews published in English. Citations from papers retrieved were screened and retrieved papers were evaluated. RESULTS Based on the screened data, we propose a practical, organ-oriented checklist protocol for the postmortem according to the HIV pathogenesis. CONCLUSIONS Evidence-based medicine is a paradigm now exerting increasing influence in related fields such as surgery, general practice, psychiatry, and pathology. This article is a summary of the literature on PAIDS pathology. The protocol that we propose is particularly useful for pediatric pathology programs and for electronic data processing.
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Study of the malformation of ductal plate of the liver in Meckel syndrome and review of other syndromes presenting with this anomaly. Pediatr Dev Pathol 2000; 3:568-83. [PMID: 11000335 DOI: 10.1007/s100240010104] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Meckel syndrome (MIM 249.000) is an autosomal recessive disorder with a variable spectrum of anomalies. Since the first reports of this syndrome, very broad diagnostic criteria have been proposed, but the process of defining them continues. It is probable that at least two of three manifestations, including cystic kidney dysplasia, occipital encephalocele or other anomaly of the central nervous system, and postaxial polydactyly occur in most cases. Arrest of the development of intrahepatic bile ducts at the stage of the bilaminar plate formation or ductal plate malformation is considered of high diagnostic value in Meckel syndrome, but there is no complete agreement in the literature about its occurrence. The aims of this investigation were to study the prevalence and morphologic patterns of ductal plate malformation of the liver in Meckel syndrome by evaluating the dilatation of primitive biliary structures and the increase in connective tissue of the portal tract. Archival data files from four German centers (Berlin, Freiburg, Heidelberg, Mainz) were reviewed. Liver sections of 30 well-studied fetuses with Meckel syndrome were immunostained with antibodies against cytokeratins (intermediate filaments of the cytoskeleton) and factor VIII (an endothelial cell marker) and were evaluated both qualitatively and quantitatively. Cystic kidney dysplasia, occipital encephalocele, and postaxial polydactyly were found in 100%, 90%, and 83.3% of the fetuses, respectively. Ductal plate malformation of the liver was a constant anomaly in Meckel syndrome, seen as frequently as renal lesions. We observed essentially two kinds of hepatic lesions: 23 cases showed mainly a cystic dilatation of primitive biliary structures with little portal fibrosis, while 7 cases showed mainly rings of interrupted curved lumina around a central fibrovascular axis and pronounced portal fibrosis. In these seven cases an abnormal pattern of the portal vein, with many small and closely spaced branches of the portal vein (the so-called pollard willow pattern), was also seen. With respect to other fetal developmental anomalies, no difference between the two types of lesions was found. We also provide a potentially useful comprehensive review of other genetic syndromes in which ductal plate malformations may occur.
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Abstract
This paper reviews the benefits that a structured format such as a protocol can bring to the delivery of nutritional support. The four main areas of influence are: (1) patient selection, in which indications for feeding and evaluation of the risk/benefit ratio are discussed; (2) timing of nutritional support, in which guidelines for initiating feeding are proposed; (3) delivery of nutrition, in which protocols to limit complications and optimize delivery are reviewed; and (4) feed content, in which guidelines for appropriate nutrients and formulation for special considerations are identified. The importance of an evidence base is stressed and some of the evidence supporting specific recommendations is reviewed.
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Moderate intervention with carotenoid-rich vegetable products reduces lipid peroxidation in men. J Nutr 2000; 130:2200-6. [PMID: 10958813 DOI: 10.1093/jn/130.9.2200] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Because of their antioxidant properties, carotenoids may have beneficial effects in preventing cancer and cardiovascular disease. However, in humans consuming carotenoid-rich vegetables, data concerning the antioxidant effects of carotenoids are rather scarce. A human intervention trial was conducted, therefore, to determine whether a moderately increased consumption of carotenoid-rich vegetables would influence the antioxidant status in 23 healthy men. This short-term feeding study lasted 8 wk during which the men consumed a low carotenoid diet. A 2-wk low carotenoid period was followed by daily consumption of 330 mL tomato juice, then by 330 mL carrot juice and then by 10 g of spinach powder, each for 2 wk. Antioxidant status [water-soluble antioxidants in serum, ferric reducing ability of plasma (FRAP) and antioxidant enzyme activities] and lipid peroxidation (plasma malondialdehyde and ex vivo oxidation of LDL) were determined. In a subgroup of 10 men, lipoprotein carotenoids were measured. The consumption of carotenoid-rich vegetables significantly increased selected carotenoids in lipoproteins but had only minor effects on their relative distribution pattern. Tomato juice consumption reduced plasma thiobarbituric acid reactive substances (TBARS) by 12% (P: < 0.05) and lipoprotein oxidizability in terms of an increased lag time (18%, P: < 0.05). Carrot juice and spinach powder had no effect on lipid peroxidation. Water-soluble antioxidants, FRAP, glutathione peroxidase and reductase activities did not change during any study period. In evaluating the low carotenoid diet, we conclude that the additional consumption of carotenoid-rich vegetable products enhanced lipoprotein carotenoid concentrations, but only tomato juice reduced LDL oxidation in healthy men.
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Analysis of the spectrum of malformations in human fetuses of the second and third trimester of pregnancy with human triploidy. Pathologica 2000; 92:257-63. [PMID: 11029886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Triploidy is constituted by an extra haploid set of chromosomes for a total of 69 chromosomes in humans. A "parent-of-origin" effect has been demonstrated by analysis of cytogenetic polymorphisms of triploidy pregnancies. Two distinct phenotypes of human triploid fetuses have been recognized according to the parental origin of the extra haploid set. The first one or triploidy of diandric type occurs when the extra haploid set of chromosomes arises from the father, the second one or triploidy of digynic type occurs when the extra haploid set of chromosomes arises from the mother. Diandric fetuses appear relatively well grown with a large placenta, while digynic fetuses show intrauterine growth retardation with a small placenta. Autopsy archive data files (1982-1998) of the Institute of Pathology, University of Heidelberg (Germany) were examined for fetuses with triploidy. We found 12 well-studied triploid fetuses (gestational age: 20 to 32 weeks). Eleven fetuses corresponded to the digynic type of triploidy and one fetus corresponded to the diandric type of triploidy. The spectrum of external malformations included a dysmorphic face (broad root of the nose, exophthalmos, low-set ears, micro-/retrognathia, microgenia, median cleft lip and/or palate, gnathoschisis, macroglossia), encephalocele, spina bifida, syndactyly, club or rocker-bottom feet, pes equino-valgus. More common internal malformations included ventricular septum defect of the heart, abnormal lobation of the lungs, and renal disease (agenesis, cysts).
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Simultaneous detection of ubiquinol-10, ubiquinone-10, and tocopherols in human plasma microsamples and macrosamples as a marker of oxidative damage in neonates and infants. Anal Biochem 2000; 282:209-17. [PMID: 10873275 DOI: 10.1006/abio.2000.4579] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A HPLC-method was developed for the simultaneous detection of the lipophilic antioxidants ubiquinol-10, ubiquinone-10, alpha-tocopherol, and gamma-tocopherol in plasma macrosamples (100 microl) as well as microsamples (10 microl) using electrochemical detection with internal standardization (gamma-tocotrienol, ubiquinol-9, ubiquinone-9). The use of a mobile phase containing ammonium formate instead of lithium perchlorate as conductivity salt and the use of a PEEK column instead of a steel column improved the reproducibility of the method. The components were separated on a RP C18 column. The detection limits for all components were between 1 and 28 fmol. The within-day precision varied between 3 and 13% for all measured substances. The analytical recovery was between 93 and 109%. The plasma levels from 10 healthy donors were determined in microsamples and macrosamples taken by micropuncture or venous puncture, respectively. A good correlation of the antioxidant levels for both methods strengthened the reliability and the transferability of the results. The present method can be used to assess the role of these antioxidants in diseases associated with oxidative damage in childhood.
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138
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[Acardius or "twin-reversed arterial prefusion" sequence. Report of four cases and review of current therapeutic possibilities]. DER PATHOLOGE 2000; 21:308-14. [PMID: 11006931 DOI: 10.1007/s002920000372] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We describe four cases of acardius (one of hemiacardius, two of holoacardius acephalus, and one of the holacardius amorphus) and present the current range of therapeutic possibilities: control of amniotic fluid by repeated amniocentesis or indomethacin therapy, administration of digoxin to the mother, selective preterm delivery of the acardiac twin by hysterotomy, interruption of the anastomoses by injection of thrombogenic coils, sclerosing agents, umbilical cord ligation, fetoscopic laser coagulation, and thermocoagulation.
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139
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Abstract
From 12 weeks of gestation on, a progressive remodeling of the human primitive biliary structure or ductal plate occurs. A few parts of the primitive biliary structure (peripheral tubular or ductular structures) dilate, migrate toward the center of the portal tract, and transform into mature bile ducts, while most of them gradually disappear. To the best of our knowledge, quantitative studies have been performed only to evaluate the ratio between the number of remodeled bile ducts and portal tracts during human fetal development. We studied the remodeling of the intrahepatic fetal biliary structures as well as the bile duct to portal tract ratio in the developing human liver by immunohistochemistry with monoclonal antibodies anti-bile duct type cytokeratins and using a computer-based image-analysis system. We found that the surface and the perimeter of the portal tracts, the longest axis of the migrating peripheral tubular structures, and the maturation of bile ducts follow a process continuous and active up to term, but they slow between the 20th and the 32nd week of gestation, when intraportal granulopoiesis of the liver is active.
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140
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Etiology, pathophysiology, treatment choices, and voice results for unilateral adductor vocal fold paralysis: a 3-year retrospective. J Voice 1999; 13:592-601. [PMID: 10622524 DOI: 10.1016/s0892-1997(99)80013-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Unilateral vocal fold paralysis is now considered a common disorder seen in the practice of otolaryngology and voice pathology. Concern first is for the accurate diagnosis of the associated etiology in an efficient and thorough fashion. When etiology has been determined the focus of treatment becomes the management of the presenting symptoms, which typically include dysphonia and dysphagia. A retrospective study was conducted reviewing the records of 117 patients with unilateral adductor vocal fold paralysis who presented to a large otolaryngology practice and clinical voice lab from 1995 to 1998. Demographic data reveal most patients to range in age from 16 to 91 with a dominant clustering for ages 50 to 70. Gender distribution reveals males slightly exceed females in this sample. Data regarding etiology type are collected in great detail, revealing that disease and surgery involving the chest contribute the greatest to the overall number in this study and that anterior approach to cervical spine surgery contributes as much as thyroid surgery. General outcomes of the patients are reviewed. A small group (n = 25) of patients who had pretreatment and posttreatment data available revealed statistically significant differences between voice outcomes for patients who were treated with medialization and for those treated with therapy. Patients receiving therapy had less severe symptoms pretreatment, while greater gains pretreatment to posttreatment were shown for those who had surgical medialization.
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141
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Abstract
Bone morphogenetic proteins (BMPs) are multifunctional cytokines. BMP-6 is involved in early steps of keratinogenesis. Esophageal squamous-cell carcinoma often shows abnormal keratinization. The aim of this study was to examine the expression and regulation of BMP-6 in esophageal carcinoma and to determine the relationship of its expression with tumor characteristics and survival. Avidin-biotin-peroxidase staining was performed using paraffin-wax-embedded tumor specimens collected from 172 patients with esophageal squamous-cell carcinoma, who underwent potentially curative surgery. Expression of BMP-6 and EGF-receptor in the esophageal-squamous-cell-carcinoma cell line COLO-680N and the hypopharyngeal-squamous-cell-carcinoma cell line FaDu was assayed with specific RT-PCR. In standard cell-cultivation conditions, COLO-680N and FaDu cells showed distinct expression of BMP-6, whereas in serum-free conditions BMP-6 expression was hardly detectable. The addition of EGF or EGF-related growth factors could elevate BMP-6 mRNA content. Immunohistochemically, all 172 tumors exhibited cytoplasmic immunoreactivity for BMP-6. The content of BMP-6 protein was inversely correlated with tumor differentiation (p < 0.01). Univariate survival analysis revealed that 74 patients with tumors of low immunoreactivity had higher 2-year and 5-year survival rates (50.0%/27.7%) than 75 patients with tumors of high immunoreactive scores (33.3%/21.6%). (p < 0.05). We conclude that BMP-6 is expressed in esophageal squamous-cell carcinoma. EGF-receptor activation is crucial for regulation of BMP-6 expression. BMP-6 protein content is correlated with the grade of tumor-cell differentiation and may add to indications of poor prognosis.
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143
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Abstract
The aggregating proteoglycans (aggrecan, versican, neurocan, and brevican) are important components of many extracellular matrices. Their N-terminal globular domain binds to hyaluronan, but the function of their C-terminal region containing a C-type lectin domain is less clear. We now report that a 90-kDa protein copurifies with recombinant lectin domains from aggrecan and versican, but not from the brain-specific neurocan and brevican. Amino acid sequencing of tryptic peptides from this protein identified it as fibulin-1. This extracellular matrix glycoprotein is strongly expressed in tissues where versican is expressed (blood vessels, skin, and developing heart), and also expressed in developing cartilage and bone. It is thus likely to interact with these proteoglycans in vivo. Surface plasmon resonance measurements confirmed that aggrecan and versican lectin domains bind fibulin-1, whereas brevican and neurocan do not. As expected for a C-type lectin, the interactions with fibulin-1 are Ca2+-dependent, with KD values in the low nanomolar range. Using various deletion mutants, the binding site for aggrecan and versican lectin domains was mapped to the epidermal growth factor-like repeats in domain II of fibulin-1. No difference in affinity was found for deglycosylated fibulin-1, indicating that the proteoglycan C-type lectin domains bind to the protein part of fibulin-1.
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144
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[Demystifying the desire for control]. THE CANADIAN NURSE 1999; 95:41-6. [PMID: 10624220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Demystifying the desire for control. Humans are constantly striving for various forms of control: to master a role or new responsibility, or to control their weight. The desire for control, therefore, is fundamental to the nursing profession because nurses are responsible for helping individuals maintain, regain or attain optimal health. Analysis of much of the literature reveals the lack of consensus on the terminology and definition of the desire for control. To remedy this shortcoming and clarify this key concept in nursing, the authors analysed this concept with the method described by Wilson, often used in nursing. The authors describe the background, characteristics and consequences of this concept. Identifying these factors should give nurses an opportunity to observe this concept in practice and to understand certain behaviors. Our view of reality shapes how we deliver care. Demystifying this concept will also open the field to research.
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Abstract
Calcification of the stylohyoid ligament is a well recognised radiographic finding in dental practice. Fortunately, affected individuals seldom develop symptoms. We report a case of a patient whose main complaint was a loud click following jaw movement. This unusual presentation has not been described before and should be considered in the differential diagnosis of 'clicking jaw'.
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146
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Abstract
Age-related changes in functional subsets of lymphocytes may influence the potential to build up immune responses. In particular, the capacity of tonsillar lymphocytes to counter infections may be altered during ageing. In order to address this question we investigated the proportional distribution of several subsets of tonsillar T and B cells with regard to ageing. Tonsils were derived from 119 patients between 2 and 65 years of age. Lymphocyte subsets were monitored by three-colour fluorescence of relevant CD markers in flow cytometry. As a general tendency the percentage of CD3+ T cells steadily increased whereas that of CD19+ B cells decreased at the same time. No significant differences were observed between lymphocytes of patients with and without inflammatory history of the tonsils. The percentage of CD8+ T cells declined whereas that of CD4+ T cells increased during the same time span. CD45RA+ T cells increased during the first two decades of life and gradually decreased thereafter. In contrast, CD45RO+ T cells showed an opposite trend. No differences were seen in the population of CD3-/CD56+ natural killer (NK) cells. The mature B cell marker CD40 showed no significant changes during ageing. However, CD38+ B cells, representing B cells of late maturation stages, dramatically declined up to the age of 65. In a similar manner the CD5+ subpopulation of B cells decreased during ageing. Substantial changes in major tonsillar T and B cell populations as shown in this study may have an impact on the ageing process of the immune system.
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147
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[Evaluation of VISY-1 in an in vivo test: sampling and glucose determination]. BIOMED ENG-BIOMED TE 1998; 43 Suppl:562-3. [PMID: 9859492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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148
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[Resting cartilage and the growth plate in dystrophic dysplasia: case report and clinicopathologic characteristics as compared to pseudodystrophic dysplasia and type II atelosteogenesis]. DER PATHOLOGE 1998; 19:379-83. [PMID: 9816594 DOI: 10.1007/s002920050301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The authors describe the histopathology of the resting cartilage and the growth plate in a case of diastrophic dysplasia and review the differential diagnosis with pseudo-diastrophic dysplasia and atelosteogenesis type II.
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149
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Abstract
We developed a new system to monitor glucose continuously in vivo. The miniaturised system is very easy to handle and was optimised to a resource-saving working modus. Sampling was performed by means of a biocompatible microdialysis needle probe inserted into the subcutaneous tissue. During glucose tolerance tests the results of our monitoring system were correlated with the glucose level of the venous blood stream. A comparison according to the procedure known as 'error grid analysis' provided an excellent correlation between the two completely independent analyses systems with the reference determination results. All values obtained with our systems were clinically correct or at least clinically acceptable.
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150
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The putative cofactor TIF1alpha is a protein kinase that is hyperphosphorylated upon interaction with liganded nuclear receptors. J Biol Chem 1998; 273:16199-204. [PMID: 9632676 DOI: 10.1074/jbc.273.26.16199] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ligand-induced gene activation by nuclear receptors (NRs) is a complex process requiring dissociation of corepressors and recruitment of coactivators. The putative transcriptional intermediary factor TIF1alpha has been previously characterized as a nuclear protein that interacts directly with the AF-2 ligand-dependent activating domain present in the ligand-binding domain of numerous steroid and nonsteroid receptors, including the estrogen (ERalpha) and retinoid X (RXRalpha) receptors. We report here that TIF1alpha is both a phosphoprotein and a protein kinase. TIF1alpha coexpressed in COS-1 cells with RXRalpha or ERalpha is phosphorylated and becomes hyperphosphorylated upon ligand treatment. This hyperphosphorylation requires the binding of TIF1alpha to transcriptionally active NRs since it is prevented by mutations either in the core (alpha-helix 12 of the ligand-binding domain) of the AF-2 activating domains of RXRalpha and ERalpha or in the NR box of TIF1alpha that are known to prevent TIF1alpha-NR interactions. Thus, TIF1alpha is a phosphoprotein that undergoes ligand-dependent hyperphosphorylation as a consequence of nuclear receptor binding. We further show that purified recombinant TIF1alpha possesses intrinsic kinase activity and that, in addition to autophosphorylation, TIF1alpha selectively phosphorylates the transcription factors TFIIEalpha, TAFII28, and TAFII55 in vitro. These latter results raise the possibility that TIF1alpha may act, at least in part, by phosphorylating and modifying the activity of components of the transcriptional machinery.
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