Step size control for efficient discrete element simulation

The step size determines the accuracy of a discrete element simulation. The position and velocity updating calculation uses a pre-calculated table and hence the control of step size can not use the integration formulas for step size control. A step size control scheme for use with the table driven velocity and position calculation uses the difference between the calculation result from one big step and that from two small steps. This variable time step size method chooses the suitable time step size for each particle at each step automatically according to the conditions. Simulation using fixed time step method is compared with that of using variable time step method. The difference in computation time for the same accuracy using a variable step size (compared to the fixed step) depends on the particular problem. For a simple test case the times are roughly similar. However, the variable step size gives the required accuracy on the first run. A fixed step size may require several runs to check the simulation accuracy or a conservative step size that results in longer run times. (C) 2001 Elsevier Science Ltd. All rights reserved.

Adrenocorticotropin stimulation tests in patients with hypothalamic-pituitary disease: low dose, standard high dose and 8-h infusion tests

Objectives Low doses of ACTH [1-24] (0.1, 0.5 and 1.0 mug per 1.73 m(2)) may provide a more physiological level of adrenal stimulation than the standard 250 mug test, but not all studies have concluded that the 1.0 fig is a more sensitive screening test for central hypoadrenalism. Eight-hour infusions of high dose ACTH [1-24] have also been suggested as a means of assessing the adrenals' capacity for sustained cortisol secretion. In this study, we compared the diagnostic accuracy of three low dose ACTH tests (LDTs) and the 8-h infusion with the standard 250 jig test (HDT) and the insulin hypoglycaemia test (IHT) in patients with hypothalamic-pituitary disease. Subjects and design Three groups of subjects were studied. A healthy control group (group 1, n=9) and 33 patients with known hypothalamic or pituitary disease who were divided into group 2 (n=12, underwent IHT) and group 3 (n=21, IHT contraindicated). Six different tests were performed: a standard IHT (0.15 U/kg soluble insulin); a 60-minute 250 mug HDT; three different LDTs using 0.1 mug, 0.5 mug and 1.0 mug (all per 1.73 m(2)); and an 8-h infusion test (250 mug ACTH [1-24] at a constant rate over 8 h). Results Nine out of the 12 patients in group 2 failed the IHT. Three out of 12 patients from group 2 who clearly passed the IHT, also passed all the ACTH [1-24] stimulation tests. Seven of the 9 patients who failed the lHT, failed by a clear margin (peak cortisol

Explicit evidence-based prescribing criteria - an important step in achieving quality therapeutics in nursing homes

Reaction between 5-(4-amino-2-thiabutyl)-5-methyl-3,7-dithianonane-1, 9-diamine (N3S3) and 5- methyl-2,2-bipyridine-5-carbaldehyde and subsequent reduction of the resulting imine with sodium borohydride results in a potentially ditopic ligand (L). Treatment of L with one equivalent of an iron( II) salt led to the monoprotonated complex [Fe(HL)](3+), isolated as the hexafluorophosphate salt. The presence of characteristic bands for the tris( bipyridyl) iron( II) chromophore in the UV/vis spectrum indicated that the iron( II) atom is coordinated octahedrally by the three bipyridyl (bipy) groups. The [Fe( bipy) 3] moiety encloses a cavity composed of the N3S3 portion of the ditopic ligand. The mononuclear and monomeric nature of the complex [Fe(HL)](3+) has been established also by accurate mass analysis. [Fe(HL)](3+) displays reduced stability to base compared with the complex [Fe(bipy)(3)](2+). In aqueous solution [Fe(HL)](3+) exhibits irreversible electrochemical behaviour with an oxidation wave ca. 60 mV to more positive potential than [Fe(bipy)(3)](2+). Investigations of the interaction of [Fe(L)](2+) with copper( II), iron( II), and mercury( II) using mass spectroscopic and potentiometric methods suggested that where complexation occurred, fewer than six of the N3S3 cavity donors were involved. The high affinity of the complex [Fe(L)](2+) for protons is one reason suggested to contribute to the reluctance to coordinate a second metal ion.

Novel molecular sieve silica (MSS) membranes: characterisation and permeation of single-step and two-step sol-gel membranes

High quality MSS membranes were synthesised by a single-step and two-step catalysed hydrolyses employing tetraethylorthosilicate (TEOS), absolute ethanol (EtOH), I M nitric acid (HNO3) and distilled water (H2O). The Si-29 NMR results showed that the two-step xerogels consistently had more contribution of silanol groups (Q(3) and Q(2)) than the single-step xerogel. According to the fractal theory, high contribution of Q(2) and Q(3) species are responsible for the formation of weakly branched systems leading to low pore volume of microporous dimension. The transport of diffusing gases in these membranes is shown to be activated as the permeance increased with temperature. Albeit the permeance of He for both single-step and two-step membranes are very similar, the two-step membranes permselectivity (ideal separation factor) for He/CO2 (69-319) and He/CH4 (585-958) are one to two orders of magnitude higher than the single-step membranes results of 2-7 and 69, respectively. The two-step membranes have high activation energy for He and H-2 permeance, in excess of 16 kJ mol(-1). The mobility energy for He permeance is three to six-fold higher for the two-step than the single-step membranes. As the mobility energy is higher for small pores than large pores and coupled with the permselectivity results, the two-step catalysed hydrolysis sol-gel process resulted in the formation of pore sizes in the region of 3 Angstrom while the single-step process tended to produce slightly larger pores. (C) 2002 Elsevier Science B.V. All rights reserved.

Extensive multiple test centre evaluation of the VecTest malaria antigen panel assay

To determine which species and populations of Anopheles transmit malaria in any given situation, immunological assays for malaria sporozoite antigen can replace traditional microscopical examination of freshly dissected Anopheles. We developed a wicking assay for use with mosquitoes that identifies the presence or absence of specific peptide epitopes of circumsporozoite (CS) protein of Plasmodium falciparum and two strains of Plasmodium vivax (variants 210 and 247). The resulting assay (VecTest(TM) Malaria) is a rapid, one-step procedure using a 'dipstick' test strip capable of detecting and distinguishing between P. falciparum and P. vivax infections in mosquitoes. The objective of the present study was to test the efficacy, sensitivity, stability and field-user acceptability of this wicking dipstick assay. In collaboration with 16 test centres world-wide, we evaluated more than 40 000 units of this assay, comparing it to the standard CS ELISA. The 'VecTest(TM) Malaria' was found to show 92% sensitivity and 98.1% specificity, with 97.8% accuracy overall. In accelerated storage tests, the dipsticks remained stable for >15 weeks in dry conditions up to 45degreesC and in humid conditions up to 37degreesC. Evidently, this quick and easy dipstick test performs at an acceptable level of reliability and offers practical advantages for field workers needing to make rapid surveys of malaria vectors.

Heat transfer and flow behind a step in high enthalpy superorbital flow

Heat transfer levels have been investigated behind a rearward-facing step in a superorbital expansion tube. The heat transfer was measured along a flat plate and behind 2 and 3mm steps with the same length to step height ratio. Results were obtained with air as the test gas at speeds of 6.76kms(-1) and 9-60kms(-1) corresponding to stagnation enthalpies of 26MJ/kg and 48MJ/kg respectively. A laminar boundary layer was established on the flat plate and measured heat transfer levels were consistent with classical empirical correlations. In the case of flow behind a step, the measurements showed a gradual rise in heat transfer from the rear of the step to a plateau several step heights downstream for both flow conditions. Reattachment distance was estimated to be approximately 1.6 step heights downstream of the 2mm step at the low enthalpy condition through the use of flow visualisation.

Single step polymerase chain reaction (PCR) for the diagnosis of the Leishmania (Viannia) subgenus

In Brazil, the main etiologic agent of Leishmaniasis that frequently presents with mucosal involvement belongs to the Viannia subgenus. The therapeutic conduct in this disease depends on the parasitological diagnosis, and classical methods are restricted in identifying the agent. In this paper we describe a polymerase chain reaction (PCR), which uses primers designed from mini-exons repetitive sequences. The PCR amplifies a 177bp fragment that can distinguish (Viannia) from (Leishmania) subgenus. This test could be a useful diagnostic tool.

Experimental characterization of the out-of-plane performance of regular stone masonry walls, including test setups and axial load influence

Stone masonry is one of the oldest and most worldwide used building techniques. Nevertheless, the structural response of masonry structures is complex and the effective knowledge about their mechanical behaviour is still limited. This fact is particularly notorious when dealing with the description of their out-of-plane behaviour under horizontal loadings, as is the case of the earthquake action. In this context, this paper describes an experimental program, conducted in laboratory environment, aiming at characterizing the out-of-plane behaviour of traditional unreinforced stone masonry walls. In the scope of this campaign, six full-scale sacco stone masonry specimens were fully characterised regarding their most important mechanic, geometric and dynamic features and were tested resorting to two different loading techniques under three distinct vertical pre-compression states; three of the specimens were subjected to an out-of-plane surface load by means of a system of airbags and the remaining were subjected to an out-of-plane horizontal line-load at the top. From the experiments it was possible to observe that both test setups were able to globally mobilize the out-of-plane response of the walls, which presented substantial displacement capacity, with ratios of ultimate displacement to the wall thickness ranging between 26 and 45 %, as well as good energy dissipation capacity. Finally, very interesting results were also obtained from a simple analytical model used herein to compute a set of experimental-based ratios, namely between the maximum stability displacement and the wall thickness for which a mean value of about 60 % was found.

Evaluation of Helicobacter pylory colonization by serologic test (IgG) and dyspepsia in volunteers from the countryside of Monte Negro, in the Brazilian western Amazon region

The present study intended to analyze the seroprevalence of Helicobacter pylori, IgG, and its relation to dyspepsia in a population from the western Amazon region. During the "Projeto Bandeira Científica", a University of São Paulo Medical School program, in Monte Negro's rural areas, state of Rondônia, 266 blood samples were collected from volunteers. The material was tested for IgG antibodies anti-Helicobacter pylori by ELISA method and the participants were also interviewed on dyspepsia, hygiene and social aspects. Participants aged between five and 81 years old (34 years on average), 149 (56%) were female and 117 (44%) male. We found 210 (78.9%) positive, 50 (18.8%) negative and six (2.3%) undetermined samples. Dyspeptic complaints were found in 226 cases (85.2%). There was no statistical association between dyspepsia and positive serology for H. pylori. We concluded that the seroprevalence in all age categories is similar to results found in other studies conducted in developing countries, including those from Brazil. On the other hand, the seroprevalence found in Monte Negro was higher than that reported in developed countries. As expected, there was a progressive increase in the positivity for H. pylori in older age groups.

Psicopatologia obsessivo-compulsiva na distonia focal primária : aspectos neuropsiquiátricos de uma doença do movimento

RESUMO: pela contracção involuntária de grupos musculares de extensão variável, originando movimentos involuntários e posturas anómalas, por vezes dolorosas. O tratamento convencional consiste em injecções localizadas de toxina botulínica, podendo, em casos refractários, estar indicado o tratamento por estimulação cerebral profunda. A neurobiologia da distonia focal primária permanece incompletamente compreendida. Os estudos de neuro-imagem estrutural e funcional revelam alterações subtis da anatomia e funcionamento do estriado e das vias cortico-basais, com destaque para o aumento do volume, da actividade metabólica e da neuroplasticidade do putamen e de áreas corticais motoras, pré-motoras e sensitivas. O conjunto destas alterações aponta para uma disrupção da regulação inibitória de programas motores automáticos sustentados pelo estriado e pelas vias ortico-subcorticais. Nos últimos anos tem crescido o interesse pelas manifestações psiquiátricas e cognitivas da distonia (estas últimas muito pouco estudadas). Tem despertado particular interesse a possível associação entre distonia focal primária e perturbação obsessivo-compulsiva (POC), cuja neurobiologia parece notavelmente sobreponível à da distonia primária. Com efeito, os estudos de neuro-imagem estrutural e funcional na POC revelam consistentemente aumento do volume e actividade do estriado e do córtex órbito-frontal, apontando mais uma vez para uma disfunção do controlo inibitório, no estriado, de programas comportamentais e cognitivos automáticos. Objectivos: 1. Explorar a prevalência e intensidade de psicopatologia em geral, e de psicopatologia obsessivo-compulsiva em particular, numa amostra de indivíduos com distonia focal primária; 2. Explorar a ocorrência, natureza e intensidade de alterações do funcionamento cognitivo numa amostra de indivíduos com distonia focal primária; 3. Investigar a associação entre a gravidade da distonia focal, a intensidade da psicopatologia, e a intensidade das alterações cognitivas. Metodologia: Estudo de tipo transversal, caso-controlo, observacional e descritivo, com objectivos puramente exploratórios. Casos: 45 indivíduos com distonia focal primária (15 casos de blefaroespasmo, 15 de cãibra do escrivão, 15 de distonia cervical espasmódica), recrutados através da Associação Portuguesa de Distonia. Critérios de inclusão: idade = 18; distonia focal primária pura (excluindo casos de distonia psicogénica possível ou provável de acordo com os critérios de Fahn e Williams); Metabolismo do cobre e Ressonância Magnética Nuclear sem alterações. Controlos doentes: 46 casos consecutivos recrutados a partir da consulta externa do Hospital Egas Moniz: 15 doentes com espasmo hemifacial, 14 com espondilartropatia cervical, 17 com síndrome do canal cárpico. Controlos saudáveis: 30 voluntários. Critérios de exclusão para todos os grupos: Mini-Mental State Examination patológico, tratamento actual com anti-colinérgicos, antipsicóticos, inibidores selectivos da recaptação da serotonina, antidepressivos tri- ou tetracíclicos. Avaliação: Avaliação neurológica: história e exame médico e neurológico completos. Cotação da gravidade da distonia com a Unified Dystonia Rating Scale. Avaliação psicopatológica: Symptom Check-List-90-Revised; entrevista psiquiátrica de 60 minutos incluindo a Mini-International Neuropsychiatric Interview (MINI), versão 4.4 (validada em Português), complementada com os módulos da MINI Plus versão 5.0.0 para depressão ao longo da vida e dependência/ abuso do álcool e outras substâncias ao longo da vida; Yale-Brown Obsessive-Compulsive Symptom Checklist e a Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). Avaliação neuropsicológica: Wisconsin Card Sorting Test (WCST; flexibilidade cognitiva); Teste de Stroop (inibição de resposta); Block Assembly Test (capacidade visuo-construtiva); Teste de Retenção Visual de Benton (memória de trabalho visuo-espacial). Análise estatística:os dados foram analisados com a aplicação informática SPSS for Windows, versão 13. Para a comparação de proporções utilizaram-se o teste do Chi-quadrado e o teste de Fisher. Para a comparação de variáveis quantitativas entre dois grupos utilizou-se o teste t de Student ou o teste U de Mann-Whitney (teste de Wilcoxon no caso de amostras emparelhadas). Para comparações de médias entre três grupos recorreu-se à Análise de Variância a um factor (variáveis de intervalo e de rácio), ou ao teste de Kruskal-Wallis (variáveis ordinais). Para o estudo da associação entre variáveis foram utilizados os coeficientes de correlação de Pearson ou de Spearman, a análise de correlações canónicas, a análise de trajectórias e a regressão logística. Adoptou-se um Alpha de 0.05. Resultados: Os doentes com distonia focal primária apresentaram uma pontuação média na Y- -BOCS significativamente superior à dos dois grupos de controlo. Em 24.4% dos doentes com distonia a pontuação na Y-BOCS foi superior a 16. Estes doentes eram predominantemente mulheres, tinham uma maior duração média da doença e referiam predominantemente sintomas obsessivo-compulsivos (SOC) de contaminação e lavagem. Os dois grupos com doença crónica apresentaram pontuações médias superiores às dos indivíduos saudáveis nas escalas de ansiedade, somatização e psicopatologia geral. Os doentes com distonia tratados com toxina botulínica apresentaram pontuações inferiores às dos doentes não tratados nas escalas de ansiedade generalizada, fobia, somatização e depressão, mas não na Y-BOCS. Sessenta por cento dos doentes com distonia apresentavam pelo menos um diagnóstico psiquiátrico actual ou pregresso. O risco de apresentar um diagnóstico psiquiátrico actual era menor nos doentes tratados com toxina botulínica, aumentando com a gravidade da doença. A prevalência de POC foi 8,3% e a de depressão major 37,7%. No WCST e na Prova de Benton, os doentes com distonia focal primária demonstraram um desempenho inferior ao de ambos os grupos de controlo, cometendo sobretudo erros perseverativos. Os doentes com distonia e pontuação na Y-BOCS > 16 cometeram mais erros e respostas perseverativas no WCST do que os restantes doentes com distonia. As análises de correlações e de trajectórias revelaram que nos doentes com distonia a gravidade da distonia foi, juntamente com a idade e a escolaridade, o factor que mais interagiu com o desempenho cognitivo. Discussão: o nosso estudo é o primeiro a descrever, nos mesmos doentes com distonia focal primária, SOC significativos e alterações cognitivas. Os nossos resultados confirmam a hipótese de uma associação clínica específica entre distonia focal primária e psicopatologia obsessivo-compulsiva. Confirmam igualmente que a distonia focal primária está associada a um maior risco de desenvolver morbilidade psiquiátrica ansiosa e depressiva. O tratamento com toxina botulínica reduz este risco, mas não influencia os SOC. Entre os doentes com distonia, os que têm SOC significativos poderão diconstituir um grupo particular com maior duração da doença (mas não uma maior gravidade), predomínio do sexo feminino e predomínio de SOC de contaminação e limpeza. Em termos cognitivos, os indivíduos com distonia focal primária apresentam défices significativos de flexibilidade cognitiva (particularmente acentuados nos doentes com SOC significativos) e de memória de trabalho visuo-espacial. Estes últimos devem-se essencialmente a um défice executivo e não a uma incapacidade visuo-construtiva ou visuo-perceptiva. A disfunção cognitiva não é explicável pela psicopatologia depressiva nem pela incapacidade motora, já que os controlos com doença periférica crónica tiveram um desempenho superior ao dos doentes com distonia. No seu conjunto os nossos resultados sugerem que os SOC que ocorrem na distonia focal primária constituem uma das manifestações clínicas da neurobiologia desta doença do movimento. O predomínio de sintomas relacionados com higiene e o perfil disexecutivo de alterações cognitivas–perseveração e dificuldades executivas de memória de trabalho visuo-espacial – apontam para a via cortico-basal dorso-lateral e para as áreas corticais que lhe estão associadas como estando implicadas na tripla associação entre sintomas motores, obsessivo-compulsivos e cognitivos. Conclusões: A distonia focal primária é um síndrome neuropsiquiátrico complexo com importantes manifestações não motoras, nomeadamente compromisso cognitivo do tipo disexecutivo e sintomas obsessivo-compulsivos. Clinicamente estas manifestações representam necessidades de tratamento que vão muito para além da simples incapacidade motora, devendo ser activamente exploradas e tratadas.-------------- ABSTRACT: Introduction: primary focal dystonia is an idiopathic movement disorder that manifests as involuntary, sustained contraction of muscular groups, leading to abnormal and often painful postures of the affected body part. Treatment is symptomatic, usually with local intramuscular injections of botulinum toxin. The neurobiology of primary focal dystonia remains unclear. Structural and functional neuroimaging studies have revealed subtle changes in striatal and cortical-basal pathway anatomy and function. The most consistent findings involve increased volume and metabolic activity of the putamen and of motor, pre-motor and somato-sensitive cortical areas. As a whole, these changes have been interpreted as reflecting a failure of striatal inhibitory control over automatic motor programs sustained by cortical-basal pathways. The last years have witnessed an increasing interest for the possible non-motor – mainly psychiatric and cognitive – manifestations of primary focal dystonia. The possible association of primary focal dystonia with obsessive-compulsive disorder (OCD) has raised particular interest. The neurobiology of the two disorders has indeed remarkable similarities: structural and functional neuroimaging studies in OCD have revealed increased volume and metabolic activity of the striatum and orbital-frontal cortex, again pointing to a disruption of inhibitory control of automatic cognitive and behavioural programs by the striatum. Objectives: 1. To explore the prevalence and severity of psychopathology – with a special emphasis on obsessive-compulsive symptoms (OCS) – in a sample of patients with primary focal dystonia;2. To explore the nature and severity of possible cognitive dysfunction in a sample of patients with primary focal dystonia; 3. To explore the possible association between dystonia severity, psychiatric symptom severity, and cognitive performance, in a sample of patients with primary focal dystonia. Methods: cross-sectional, case-control, descriptive study. Cases: forty-five consecutive, primary pure focal dystonia patients recruited from the Portuguese Dystonia Association case register (fifteen patients with blepharospasm, 15 with cervical dystonia and 15 with writer’s cramp). Inclusion criteria were: age = 18; primary pure focal, late-onset dystonia (excluding possible or probable psychogenic dystonia according to the Fahn & Williams criteria); normal copper metabolism and Magnetic Resonance Imaging. Diseased controls: forty-six consecutive subjects from our hospital case register (15 patients with hemi-facial spasm; 14 with cervical spondilarthropathy and cervical spinal root compression; 17 with carpal tunnel syndrome). Healthy controls were 30 volunteers.Exclusion criteria for all groups: Mini-Mental State Examination score below the validated cut-off for the Portuguese population (<23 for education between 1 and 11 years; <28 for education >11 years); use of anti-cholinergics, neuroleptics, selective serotonin reuptake inhibitors, triciclic or tetraciclic antidepressants. Assessment: neurological assessment: complete medical and neurological history and physical examination; dystonia severity scoring with the Unified Dystonia Rating Scale. Psychiatric assessment:Symptom Check-List-90-Revised; 60 minute-long psychiatric interview, including Mini-International Neuropsychiatric Interview (MINI), version 4.4 (validated Portuguese version), extended with the sections for life-time major depressive disorder and life-time alcohol and substance abuse disorder from MINI-Plus version 5.0.0; Yale-Brown Obsessive-Compulsive Symptom Checklist and Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). Cognitive assessment: Wisconsin Card Sorting Test (WCST; cognitive set-shifting ability); Stroop Test (response inhibition); Block Assembly Test(visual-constructive ability); Benton’s Visual Retention Test (visual-spatial working memory). Statistic analysis: Data were analyzed with SPSS for Windows version 13. Proportions were compared using Chi-Square test, or Fisher’s exact test when appropriate. Student’s t-test or Mann-Whitney’s U test (or Wilcoxon’s teste in the case of matched samples) were used for two-group comparisons. P-values were corrected for multiple comparisons. One-way ANOVA with Bonferroni post-hoc analysis (interval data), or the Kruskal-Wallis Test (ordinal data), were used for three-group comparisons. Associations were analysed with Pearson’s or Spearman’s correlation coefficients, canonical correlations, path analysis and logistic regression analysis. Alpha was set at 0.05. Results: Dystonia patients had higher Yale-Brown Obsessive-Compulsive Symptom scores than both control groups. 24.4% of primary dystonia patients had a Y-BOCS score > 16. These patients were predominantly women; they had longer disease duration, and showed a predominance of hygiene-related OCS. The two groups with chronic disease had higher anxiety, somatization and global psychopathology scores than healthy subjects. Primary dystonia patients undergoing treatment with botulinum toxin had lower anxiety, phobia, somatization and depression scores than their untreated counterparts, but similar Y-BOCS scores. Sixty percent of primary dystonia patients had at least one lifetime psychiatric diagnosis. The odds of having a currently active psychiatric diagnosis were lower in botulinum toxin treated patients, and increased with dystonia severity. The prevalence of OCD was 6.7%, and the lifetime prevalence of major depression was 37.7%. Primary dystonia patients had a lower performance than the two control groups in both the WCST and Benton’s Visual Retention Test, mainly due to an excess of perseveration errors. Primary dystonia patients with Y-BOCS score > 16 had much higher perseveration error and perseveration response scores than dystonia patients with Y-BOCS = 16. Correlation and path analysis showed that, in the primary dystonia group, dystonia severity, along with age and education, was the main factor influencing cognitive performance. Discussion: our study is the first description ever of concomitant significant OCS and cognitive impairment in primary dystonia patients. Our results confirm that primary dystonia is specifically associated with obsessive-compulsive psychopathology. They also confirm that primary focal dystonia patients are at a higher risk of developing anxious and depressive psychiatric morbidity. Treatment with botulinum toxin decreases this risk, but does not influence OCS. Primary focal dystonia patients with significant OCS may constitute a particular subgroup. They are predominantly women, with higher disease duration (but not severity) and a predominance of hygiene related OCS.In terms of cognitive performance, primary focal dystonia patients have significant deficits involving set-shifting ability and visual-spatial working memory. The latter result from an essentially executive deficit, rather than from a primary visual-constructive apraxia or perceptual deficit. Furthermore, cognitive flexibility difficulties were more prominent in the subset of primary dystonia patients with significant OCS. The cognitive dysfunction found in dystonia patients is not attributable to depressive psychopathology or motor disability, as their performance was significantly lower than that of similarly impaired diseased controls. Our results suggest that OCS in primary focal dystonia are a direct, primary manifestation of the motor disorder’s neurobiology. The predominance of hygiene-related symptoms and the disexecutive pattern of cognitive impairment – set-shifting and visual-spatial working memory deficits – suggest that the dorsal-lateral cortical-basal pathway may play a decisive role in the triple association of motor dysfunction, OCS and cognitive impairment. Conclusions: primary focal dystonia is a complex neuropsychiatric syndrome with significant non- -motor manifestations, namely cognitive executive deficits and obsessive-compulsive symptoms.Clinically, our results show that PFD patients may have needs for care that extend far beyond a merely motor disability and must be actively searched for and treated.

Expressão e purificação da proteína E3 do vírus chikungunya (CHIKV)

RESUMO: O vírus chikungunya (CHIKV) é um vírus de RNA, com invólucro, da família Togaviridae, transmitido por mosquitos Aedes spp. Distribuído por largas regiões de África e Ásia, causa grandes epidemias de artrite grave. A semelhança de sintomas com outras doenças como a dengue e a malária e a persistência de IgM específicas, dificultam o diagnóstico da infeção por CHIKV. A deteção no sangue de E3, uma glicoproteína viral secretada, a incluir num ensaio imunoenzimático poderá melhorar o diagnóstico nos países onde as técnicas de biologia molecular são de difícil acesso. Para testar a utilidade de E3 num ensaio de diagnóstico, esta deverá ser expressa em quantidade, purificada e usada para produção de anticorpos específicos. Para expressar E3 numa forma solúvel, suscetível de ser purificada num único passo cromatográfico sem proteases, recorreu-se à estratégia da fusão com o domínio de ligação à quitina (CBD)-inteína (IMPACT™ System, NEB). A sequência codificadora de E3 foi amplificada a partir de RNA viral, clonada em pTYB21 e expressa em E. coli como uma proteína de fusão insolúvel de 64 kDa. A expressão a 12ºC induzida por IPTG 0,1 mM aumentou a solubilidade de CBD-inteína-E3. A aplicação de lisados celulares em colunas de quitina originou a retenção de CBD-inteína-E3 na matriz. Porém, a autoclivagem da inteína na coluna, induzida com reagentes tiol, foi pouco eficiente e mesmo a proteína E3 separada não eluiu da coluna. E3 foi ainda expressa em E. coli com uma cauda de seis histidinas (E3[His]6) por clonagem no vetor pET28b(+). Lisados celulares aplicados em colunas de níquel permitiram a eluição de uma proteína de 9 kDa, compatível com a massa molecular estimada para E3[His]6, ainda que com outros contaminantes proteicos. A identidade da proteína de 9 kDa será confirmada pela indução de anticorpos com esta preparação e reatividade daqueles com células infetadas com CHIKV.----------------ABSTRACT: Chikungunya virus (CHIKV) is an enveloped, positive strand RNA virus belonging to the family Togaviridae. Transmitted by Aedes spp mosquitoes, CHIKV causes large epidemics of severe arthritogenic disease in Africa and Asia and represents a serious threat in countries where vectors are present. Symptoms similarity with other diseases, e.g. dengue and malaria, along with CHIKV IgM persistence turns accurate CHIKV diagnosis a difficult task in low-income countries. Detection of E3, a small secreted viral glycoprotein, to be included in an immunoenzymatic test was envisaged as a possible improvement in CHIKV diagnosis. To test the diagnostic value of E3, recombinant E3 should be expressed and purified to generate antibodies. In order to express CHIKV E3 in a soluble form amenable to purification by a single step affinity chromatography, the chitin binding domain (CBD)-intein fusion strategy without proteases (IMPACT™ System, NEB) was employed. The E3 coding sequence was amplified from viral RNA, cloned in pTYB21 and expressed in E. coli ER2566 as an insoluble 64 kDa CBD-intein-E3 fusion protein. Solubility was partially achieved by lowering the expression temperature to 12ºC and the inducer (IPTG) concentration to 0.1 mM. Clarified cell lysate loaded onto a chitin column allowed ligation of the fusion protein but the intein-mediated cleavage efficiency was low and E3 failed to elute from the column as demonstrated by SDS-PAGE. E3 was further expressed with a six histidine tag, E3[His]6, employing the pET System (Novagen). E3[His]6 was expressed in E. coli Rosetta (30ºC, 0.4 mM IPTG) as a 9 kDa protein. Soluble cell extracts in 20-40 mM imidazole, applied onto a nickel column and eluted with 500 mM imidazole yielded a protein preparation enriched in the 9kDa protein. The 9 kDa will be used as antigen to generate antibodies that upon reaction with CHIKV infected cells will confirm its identity.

The usefulness of Umelosa hepatitis C vírus qualitative kit as supplemental test for confirmation of hepatitis C virus infection

Forty voluntary blood donors from two different blood banks in Havana, Cuba, who were repeatedly reactive on the routine screening of antibodies to hepatitis C virus, by Umelisa HCV test, were analyzed for the presence of HCV RNA using a nested PCR assay of the HCV 5' untranslated region, Umelosa HCV qualitative. Sera from 45 patients of a specialized gastroenterology consultation, positive to Umelisa HCV, were also assayed with the Umelosa HCV qualitative, to establish their condition related to the presence of HCV RNA previously to the indication of a treatment or after three, six or twelve months of antiviral therapy. Serum HCV-RNA was detected in 21/40 (52.5%) donors who had repeatedly positive ELISA results, confirming the HCV infection for them. In specialized consultation HCV-RNA was detected by PCR analysis in 30/45 (66%) analyzed sera.

Perfil imunológico de grávidas atópicas versus grávidas saudáveis

RESUMO: A prevalência das doenças atópicas tem vindo a aumentar, em especial ao nível dos países ocidentalizados. Vários fatores têm sido apontados para justificar este aumento de prevalência,destacando-se o reduzido tamanho das famílias, o elevado uso de antibióticos, a melhoria das condições sanitárias, bem como a diminuição quer das infeções de helmintas, quer da contaminação orofecal. Alguns estudos têm também avaliado a influência do ambiente pré-natal no desenvolvimento de atopia e asma. Da análise da literatura, parece inegável a importância deste período para o desenvolvimento do sistema imunitário. Neste âmbito, a transmissão de atopia à descendência em mulheres atópicas, e concretamente com asma alérgica, poderá ser moldada desde este período. A possibilidade de identificar marcadores de risco precoces para o desenvolvimento de atopia poderá ser o primeiro passo para o desenvolvimento de estratégias de prevenção para os indivíduos em risco. Este trabalho pretendeu abordar o sistema imunitário materno de forma a enriquecer a sua caraterização desde o terceiro trimestre da gravidez até ao fim do puerpério. Para além da exploração de perfis celulares e citocínicos maternos (nos quais se incluiu sobretudo a avaliação de diferentes populações de células T e B, com funções efetoras e reguladoras), foi também considerada a sua eventual relação com o desenvolvimento de atopia nas crianças. Foram recrutadas 135 mulheres com critérios para serem incluídas num dos 4 grupos do estudo: grávidas atópicas – GA (n=24), não grávidas atópicas – NGA (n=32), grávidas saudáveis – GS (n=44) e não grávidas saudáveis – NGS (n=35). Foram caraterizadas por Citometria de Fluxo populações de leucócitos e linfócitos, com particular interesse nos perfis maturativos de linfócitos T e B, bem como nas subpopulações de células T e B reguladoras. Foi ainda efetuada uma análise funcional, para avaliar a capacidade de produção de citocinas pelos linfócitos T e B. Foram igualmente avaliadas as concentrações de citocinas séricas por ensaios imunoenzimáticos. Estes parâmetros imunológicos maternos foram acompanhados desde o terceiro trimestre de gestação, até depois do puerpério (primeiras 6 semanas pós parto), e aos seis meses de idade, foi efetuada uma avaliação clínica das crianças. As mulheres não grávidas atópicas apresentaram contagens celulares mais elevadas para a generalidade das populações leucocitárias e linfocitárias (em relação a mulheres não grávidas saudáveis). Destaca-se ainda uma maior presença de eosinófilos nas mulheres NGA (p=0,0009; teste de Mann-Whitney U), que tinham igualmente os seus compartimentos linfocitários T e B mais ricos em células de memória, em relação às mulheres NGS. Para os perfis de regulação, verificou-se que as células T reguladoras se encontravam percentualmente aumentadas (p≤0,003; teste de Mann-Whitney U), tal omo as células T produtoras de IL10 após estimulação (p≤0,03; teste de Mann-Whitney U) em mulheres NGA. Também se observou uma maior expressão de Foxp3 (p=0,0002; teste de Mann-Whitney U), e ainda a diminuição dos níveis séricos de IFN-γ nas mulheres NGA (p=0,0019; teste de Mann-Whitney U), em relação a mulheres NGS. De um modo geral, as alterações verificadas nos parâmetros imunológicos de mulheres grávidas atópicas no terceiro trimestre da gravidez foram semelhantes às observadas em mulheres grávidas saudáveis. Comparadas com mulheres NGA, nas mulheres grávidas atópicas ocorreu uma alteração substancial da fórmula leucocitária, com um importante incremento de neutrófilos (p<0,0001; teste de Mann-Whitney U) e diminuição dos valores das restantes populações leucocitárias. A diminuição nas contagens de linfócitos totais estendeu-se a grande parte das subpopulações linfocitárias caraterizadas. Nos compartimentos linfocitários T e B foi possível observar uma diminuição das subpopulações de células de memória. Verificou-se igualmente na gravidez uma menor expressão de Foxp3 em mulheres GA (p<0,0001; teste de Mann-Whitney U) e ainda menos células B CD24HiCD38Hi circulantes (p=0,0012; teste de Mann-Whitney U). Ocrreu ainda uma diminuição relativa das células T CD4 produtoras de IFN-γ em mulheres GA (p≤0,024; teste de Mann-Whitney U), e uma maior presença de células T CD8 produtoras de IL17 (p=0,0172; teste de Mann-Whitney U), em relação ao observado em mulheres NGA. Depois do puerpério, no compartimento T de mulheres do grupo GA, verificou-se um aumento das populações de células de memória. Em comparação com a gravidez, após o puerpério o compartimento B, apresentou nas mulheres GA um aumento significativo da subpopulação de células B de transição (p<0,0001; teste de Wilcoxon). Verificou-se, igualmente em mulheres GA após o puerpério, uma maior expressão de Foxp3 nas células T reguladoras (p<0,0001; teste de Wilcoxon) e o aumento das populações de células T circulantes produtoras de IFN-γ (p≤0,0234; teste de Wilcoxon). As modulações das populações T e B desde a gravidez até depois do puerpério ocorreram de forma semelhante nas mulheres dos grupos GA e GS. Apesar de as mulheres GA manterem um perfil imunológico próximo do das mulheres GS depois do puerpério, aconteceu também neste período um processo de reaproximação ao perfil observado nas mulheres NGA. As mulheres GA com manifestações de risco para atopia na descendência (comparadas com mulheres GA sem manifestações de risco para atopia na descendência até aos 6 meses de vida) apresentaram uma maior proporção de células T e menor proporção de células B, percentagens mais elevadas de células T CD8 de memória efetoras, de células B de transição e de células B CD24HiCD38Hi, e contagens mais baixas de células B de memória. Na avaliação destes parâmetros como marcadores de risco para o desenvolvimento de atopia verificou-se que o parâmetro com melhor desempenho foi a percentagem de células B de transição, com uma Odds-Ratio de 54,0 [IC 95%: 4,2-692,9; (p=0,0005)], sensibilidade de 90,0% [IC 95%: 55,5 – 99,8] e especificidade de 85,7% [IC 95%: 57,2 – 98,2]. Este estudo foi pioneiro em Portugal, e no mundo, no que se refere ao acompanhamento do compartimento linfocitário B circulante, abordando o seu perfil de maturação, e em particular as células B com funções reguladoras, desde a gravidez até ao fim do puerpério, em mulheres atópicas e não atópicas. A este nível, encontram-se estudos na literatura a documentar a alteração do compartimento B durante a gravidez. O presente trabalho reporta agora que alterações, como a diminuição do número de células B em circulação, são impostas também na mulher atópica. Em suma, demonstrou-se a existência de um perfil imunológico caraterístico em mulheres atópicas, que sofre alterações significativas durante a gravidez, tendendo os parâmetros imunológicos a normalizar após o puerpério. O compartimento T, para o qual a literatura é mais rica em estudos e abordagens, demonstrou também neste trabalho oscilações caraterísticas entre o período pré e pós-natal. Verificaram-se sobretudo variações nos compartimentos de células T de memória, sem grandes alterações ao nível das células Treg no que se refere à sua presença em circulação. Apenas a registar a menor expressão de Foxp3 nas células Treg durante a gestação observada em mulheres atópicas, tal como em mulheres saudáveis (como também já foi relatado em estudos anteriores). Apesar de muitos dos dados se encontrarem em concordância com a literatura, quer no que se refere às subpopulações de células de memória, quer no que se refere às células Treg, também se encontram resultados discordantes, por exemplo documentando variações numéricas nas células Treg em circulação em mulheres atópicas e mulheres atópicas grávidas. A importância de harmonizar protocolos e fenótipos, parece crucial na abordagem de estudos futuros. Ao nível do risco para a atopia na descendência de mulheres atópicas, acrescentou-se ainda a possibilidade de definir marcadores não invasivos para a criança, em particular as células B de transição. Estas células, cuja maior presença em circulação no recém-nascido foi recentemente associada com manifestações alérgicas subsequentes, são agora apontadas já na mulher atópica, grávida do terceiro trimestre, como um elemento de risco para o desenvolvimento de atopia. Os marcadores de risco descritos, para além de facilmente poderem vir a ser englobados no âmbito dos normais rastreios maternos durante a gravidez, apresentam ainda a vantagem da precocidade do diagnóstico, permitindo não só a possibilidade de prevenção pós-natal, mas estendendo esta possibilidade ao período gestacional.----------------------------ABSTRACT: The prevalence of atopic diseases has been increasing, especially in Westernized countries. Several factors have been suggested to justify this increase in prevalence, as the small size of families, the high use of antibiotics, the improvement in sanitation conditions, as well as the reduction of both helminth infections, and orofecal contamination. A few studies have adressed the influence of prenatal environment on the development of atopy and asthma. From literature, it seems undeniable the importance of the prenatal period for the development of the immune system. In this context, the transmission of atopy to the progeny in atopic women, and specifically in women with allergic asthma, can be modulated from this period on. The ability to detect early risk markers for the development of atopic diseases may be the first step in the development of prevention strategies for individuals at risk. This study aimed to approach the maternal immune system in order to enrich its characterization from the third trimester of pregnancy until the end of the puerperium period. In addition to the evaluation of the maternal cellular profiles (in which, mostly, diferente populations of T and B cells with effector and regulatory functions were included) and citokines, the relation between these profiles and the development of atopy in the progeny was also assessed. 135 women were recruited for this study, and fullfiled the inclusion criteria necessary to be included in one of the four groups preset: atopic pregnant women - GA (n = 24), atopic nonpregnant women - NGA (n = 32), healthy pregnant women - GS (n = 44) and healthy nonpregnant women - NGS (n = 35). Populations of leukocytes and lymphocytes, and particularty maturation profiles of T and B lymphocytes, as well as subpopulations of T and B cells with regulatory functions, were characterized by flow cytometry. Functional assays were also performed, to assess the ability of cytokine production by T and B lymphocytes. Serum cytokine concentrations were assessed as well by enzymatic immunoassays. These maternal imune parameters were monitored since the third trimester of pregnancy until the end of the puerperium period (first six weeks after delivery). A clinical evaluation of all the newborn children was performed at the age of six months. Non-atopic pregnant women presented higher cell counts for most leukocyte and lymphocyte populations (compared to healthy non-pregnant women). We should also highlight the increased presence of eosinophils in NGA women (p = 0,0009; Mann-Whitney U test). Again compared to NGS women, NGA women showed increased memory cells within the circulating T and B lymphocyte compartments. Considering the regulatory profiles, NGA women presented higher percentages of regulatory T cells (p≤0,003; Mann-Whitney U test) and IL10 producing T cells after stimulation (p≤0,03; Mann Whitney U), as well as increased expression of Foxp3 (p = 0,0002; Mann-Whitney U test), and also decreased serum levels of IFN-γ (p = 0,0019; test Mann-Whitney U test) compared to NGS women. In general, the changes observed in immune parameters of atopic pregnant women in the third trimester of gestation were similar to those observed in healthy pregnant women. Comparing pregnant and non-pregnant atopic women, an important change in leukocyte subsets was observed, with a significant increase of neutrophils (p <0,0001; Mann-Whitney U test) and the consequent diminution of the remaining leukocyte populations in the GA group. The decrease in total lymphocyte counts was extended to most of the lymphocyte subsets characterized. It was possible to detect a decrease in memory cell subsets within the T and B lymphocyte compartments, also. During pregnancy, a lower expression of Foxp3 was reported in GA women (p <0,0001; Mann-Whitney U test) and, besides, lesser CD24HiCD38Hi B cells were present in circulation in these women, compared to NGA women (p = 0,0012; Mann-Whitney U test). There was still a decrease in the percentages of IFN-γ-producing CD4 T cells in GA women (p≤0,024; Mann-Whitney U test) and a greater presence of IL17-producing CD8 T cells (p = 0,0172; Mann-Whitney U test), compared to the levels observed in NGA women. At the end of the puerperium, there was an increase in memory cell subpopulations within the T cell compartment of GA women. Compared with the pregnancy evaluation, after puerperium, the B cell compartment showed a significant increase in the transitional subpopulation (p<0,0001; Wilcoxon test), in GA women. Moreover, after puerperium, GA women exhibited a greater expression of Foxp3 in Treg cells (p <0,0001; Wilcoxon test) and there was an increase in circulating IFN-γ-producing T cells (p≤0,0234; Test Wilcoxon). The modulations of T and B cell subpopulations from pregnancy until the end of puerperium were similar in women of GA and GS groups. Although at the end of puerperium, GA women still kept an immune profile close the one observed in GS women, at this time point, there were also signs of rapprochement between the immune profiles observed in women of GA and NGA groups. GA women with atopic manifestations in the offspring (compared to GA women without atopic manifestations in the offspring at the age of 6 months) presented higher proportions of T cells and lower proportions of B cells, higher percentages of effector memory CD8 T cells, transitional B cells and CD24HiCD38Hi B cells, and, finally, lower absolute counts of memory B cells. In the evaluation of these parameters as risk markers for the development of atopy, the parameter which presented the best performance was the percentage of transitional B cells, with an Oddsratio of 54,0 [95% CI: 4,2 to 692,9; (p = 0,0005)], sensitivity of 90,0% [95% CI: 55,5 to 99,8] and a specificity of 85,7% [95% CI: 57,2 to 98,2]. This study was a pioneer in Portugal, and in the world, in what concerns the monitoring of the circulating B cell compartment, addressing not only the maturation profile, but, in particular, B cells with regulatory functions, from pregnancy untill after puerperium, in atopic and non-atopic women. Literature presents evidence of a typical change in circulating B cells during pregnancy. This study now reports that changes, such as the decrease in the number of circulating B cells,/ are also imposed by pregnancy in atopic woman. In brief, it demonstrated the existence of a characteristic immune profile in atopic women, which undergoes significant alterations during pregnancy, tending to normalize after the puerperium. As for the T cell compartment, for which the literature is richer in studies and approaches, this study also showed characteristic fluctuations between the pre- and postnatal periods. There were variations mostly in the memory subsets within the T cell compartment, without major changes in regulatory T cells regarding their presence in circulation. Only the expression of Foxp3 in Treg cells presented lower levels during pregnancy, in both atopic and healthy women (as previously reported in other studies). Although much of the data now reported are in agreement with literature, regarding either memory cell subsets or regulatory T cells, there are also conflicting results, for example documenting changes in the numbers of regulatory T cells circulating in atopic pregnant and atopic non-pregnant women. The importance of harmonizing protocols and phenotypes seems crucial for the establishement of future studies. Considering the risk for atopy in the offspring of atopic women, this study added the possibility to define non-invasive markers for the child, in particular transitional B cells. These cells, whose greater presence in circulation in newborns has recently been associated with subsequent allergy development, are here identified in atopic pregnant women in the third trimester of gestation as a risk factor in the development of atopy in their progeny. The risk factors described, besides having the capacity to easily become integrated within the normal maternal screening protocols during pregnancy, also have the advantage of an early diagnosis, allowing not only the possibility of postnatal prevention but extending this possibility to the prenatal period.

Desenvolvimento de microcápsulas ativadas por radiação solar para aplicação em painéis cerâmicos exteriores

Dissertação de mestrado integrado em Engenharia de Materiais

Physical Stress Echocardiography: Prediction of Mortality and Cardiac Events in Patients with Exercise Test showing Ischemia

Background: Studies have demonstrated the diagnostic accuracy and prognostic value of physical stress echocardiography in coronary artery disease. However, the prediction of mortality and major cardiac events in patients with exercise test positive for myocardial ischemia is limited. Objective: To evaluate the effectiveness of physical stress echocardiography in the prediction of mortality and major cardiac events in patients with exercise test positive for myocardial ischemia. Methods: This is a retrospective cohort in which 866 consecutive patients with exercise test positive for myocardial ischemia, and who underwent physical stress echocardiography were studied. Patients were divided into two groups: with physical stress echocardiography negative (G1) or positive (G2) for myocardial ischemia. The endpoints analyzed were all-cause mortality and major cardiac events, defined as cardiac death and non-fatal acute myocardial infarction. Results: G2 comprised 205 patients (23.7%). During the mean 85.6 ± 15.0-month follow-up, there were 26 deaths, of which six were cardiac deaths, and 25 non-fatal myocardial infarction cases. The independent predictors of mortality were: age, diabetes mellitus, and positive physical stress echocardiography (hazard ratio: 2.69; 95% confidence interval: 1.20 - 6.01; p = 0.016). The independent predictors of major cardiac events were: age, previous coronary artery disease, positive physical stress echocardiography (hazard ratio: 2.75; 95% confidence interval: 1.15 - 6.53; p = 0.022) and absence of a 10% increase in ejection fraction. All-cause mortality and the incidence of major cardiac events were significantly higher in G2 (p < 0. 001 and p = 0.001, respectively). Conclusion: Physical stress echocardiography provides additional prognostic information in patients with exercise test positive for myocardial ischemia.