Difficulties in diagnosing atypical primary HIV-1 infection

Several cases of primary HIV-1 infection are not identified, either because the diagnosis is not suspected or because they test negative for HIV-1 antibody. This work presents an uncommon case of primary HIV-1 infection in an young parenteral drug abuser man, who presented symptoms of acute hepatitis. During the initial acute phase the serum sample of the patient tested negative for the presence of antibodies against several viruses, including HIV-1. Nevertheless, the diagnosis of primary HIV-1 infection was suspected by using an alternative method for"in vitro" induced antibody production (IVIAP), and confirmed by p24 antigen serum positivity and seroconversion in serial plasma samples of the patient. The authors suggest the use of the IVIAP and others complementary assays to help the diagnosis of acute HIV-1 infection in persons at high risk conditions.

Altera����es da subst��ncia branca cerebral relacionadas com o envelhecimento

INTRODU����O: Estudos pr��vios, com t��cnicas de imagem, documentam de forma consistente a exist��ncia de altera����es da subst��ncia branca cerebral relacionadas com o envelhecimento (ASBRE). Tais altera����es poder��o ter um papel importante no decl��nio funcional do idoso, reflectindo���se sobretudo no desempenho motor e cognitivo, com repercuss��o evidente na pr��tica cl��nica. Apesar disso, a caracteriza����o em definitivo dos fen��tipos cl��nicos e da evolu����o das ASBRE continua por esclarecer, possivelmente pelas dificuldades metodol��gicas de que se reveste o seu estudo, incluindo: a adequa����o das baterias neuropsicol��gicas, a utiliza����o de amostras de doentes com diferentes graus de severidade e de envolvimento regional, as limita����es das diferentes escalas e a sensibilidade dos diferentes m��todos de imagem. A Resson��ncia Magn��tica (RM) de difus��o tem revelado grande sensibilidade para as altera����es isqu��micas, admitindo���se que poder�� permitir uma melhor caracteriza����o das ASBRE e deste modo possibilitar uma correla����o mais precisa com as vari��veis cognitivas e motoras, permitindo avaliar ainda a subst��ncia branca aparentemente normal (SBAN). OBJECTIVOS: Descrever a evolu����o imagiol��gica das ASBRE no intervalo de um ano e analisar a sua express��o cl��nica e impacto funcional; identificar factores preditivos de progress��o das ASBRE e de decl��nio funcional associado. Descrever a express��o cl��nica e perfil evolutivo dos doentes com ASBRE com envolvimento preferencial da regi��o parieto���occipital; comparar este grupo de doentes com os doentes com ASBRE, sem envolvimento preferencial desta regi��o. Medir os coeficientes de difus��o aparente (CDA), utilizando regi��es de interesse (RDI), em diferentes localiza����es da subst��ncia branca, incluindo subst��ncia branca lesada e SBAN, descrever sua evolu����o temporal no intervalo de um ano e determinar suas correla����es cl��nicas e imagiol��gicas. M��TODOS: Utilizando uma amostra de conveni��ncia, foram estudados 30 doentes, com mais de 65 anos, sem incapacidade funcional ou com incapacidade m��nima, avaliada pela escala de actividades instrumentais da vida di��ria (IADL), apresentando ASBRE em TC. Foi utilizado um protocolo exaustivo de avalia����o cl��nica (com particular destaque para as fun����es motoras e cognitivas) e imagiol��gica, em dois momentos de avalia����o separados por um ano de intervalo (t0 e t1). As ASBRE foram avaliadas com escalas visuais, escala ARWMC e escala de Fazekas, e os doentes foram estudados em fun����o do grau de severidade (ligeiro versus moderado a grave na escala de Fazekas) e de um envolvimento preferencial posterior (definido como 2 ou mais pontos na escala ARWMC na regi��o parieto���occipital por compara����o com a regi��o frontal). Os CDA foram avaliados mediante estudo de RDI, na subst��ncia branca frontal lesada (SBFL) e SBAN frontal, parieto���occipital e dos ped��nculos cerebelosos. Para verificar diferen��as na ordem de distribui����o das vari��veis foi usado o teste de Mann���Whitney e para compara����o de propor����es, o teste exacto de Fisher. Na compara����o entre a avalia����o em t0 e t1 foi usado o teste Wilcoxon Signed Ranks na compara����o da distribui����o da ordem das vari��veis e o teste McNemar na an��lise de frequ��ncias. Na an��lise correlacional foram utilizados os testes de T para vari��veis emparelhadas e as correla����es entre estas foram efectuadas com o coeficiente de correla����o de Spearman ou de Pearson. O trabalho foi aprovado pela Comiss��o de ��tica do hospital onde foi realizado e todos os doentes inclu��dos assinaram um consentimento informado. RESULTADOS: A idade m��dia da popula����o estudada foi 72,5 anos (17 doentes eram do sexo masculino). No final de um ano, 1 doente tinha falecido e 3 doentes n��o completaram a avalia����o imagiol��gica. Registou���se uma progress��o significativa das ASBRE segundo a escala ARWMC (t0: 8,37 / t1: 9,65 ; p<0,001). Na an��lise funcional, motora e cognitiva, n��o houve um agravamento significativo. Avaliando os doentes em t0 e t1 segundo o grau de severidade das ASBRE, o grupo com atingimento moderado a grave (ASBRE2) comparado com o grupo com atingimento ligeiro (ASBRE1) apresentava: maior extens��o de les��o da subst��ncia branca (ARWMC t0: 11,9 / 4,8 ; p<0.001 ; t1: 14,0 / 5,9 ; p<0,001); tend��ncia a pior desempenho funcional (IADL t0: 90,7 / 99,2 ; p=0,023; t1: 86,4 / 96,7 ; p=n.s.) e motor (SPPB t0: 9,8 / 10,3 ; p=n.s. ; t1: 9,5 / 10,5 ; p=0,058); tend��ncia a maior compromisso do humor (Escala Cornell t0: 6,7 / 3,5 ; p=0,037; t1: 6,2 / 4,5 ; p=n.s.). Analisando a evolu����o, de t0 para t1, de cada um dos grupos (ASBRE2 e ASBRE1) registou���se: aumento da extens��o da les��o da subst��ncia branca em ambos (ASBRE2: 12,0 / 14,0;z=���2,687 ; p=0,007; ASBR1: 4,8 / 5,9 ; z=���2,724 ; p=0,006); varia����o n��o significativa funcional e motora; tend��ncia ao agravamento em ambos na prova de Cancelamento de d��gitos (ASBRE2: 17,5 / 17,4 ; p=n.s. ; ASBRE1: 19,9 / 16,9 ; z=���2,096 ; p=0,036);tend��ncia �� melhoria em ambos no MMS (ASBRE2: 25,7 / 27,5 ; z=���2,155 ; p=0,031; ASBRE1: 27,5 / 28,2 ; p=n.s). Avaliando os doentes em t0 e t1 em fun����o do padr��o de distribui����o das ASBRE, os doentes com um envolvimento preferencial posterior (ASBREP) comparados com os restantes (ASBREnP), apresentavam: maior extens��o da les��o (ARWMC t0: 10,8 / 6,9 ; p=0,025; t1: 12,9 / 7,6 ; p=0,011); diferen��as n��o significativas no desempenho motor; tend��ncia a melhor desempenho na prova dos Labirintos (t0: 8,1 / 11,8 ; p=0,06; t1: 8,7 / 9,5 ; p=n.s.) e Cancelamento de d��gitos (t0: 20,9 / 17,4 ; p=0,045; t1: 18,5 / 16,3 ; p=n.s.); tend��ncia a maior compromisso depressivo na GDS (t0: 5,0 / 3,68 ; p=n.s. ; t1: 5,7 / 3,3 p=0,033). Analisando o perfil evolutivo de t0 para t1, registou���se: aumento da extens��o da les��o nos dois grupos (ASBREP: 10,8 / 12,9 ; z=���2,555 ; P=0,011; ASBREnP: 6,4 / 7,6 ; z=���2,877 ; p=0,04); varia����o em sentidos diferentes com melhoria funcional no grupo ASBREP (91,0 / 95,5 ; z=���0,926 ; p=0,036) e agravamento no grupo ASBREnP (96,7 / 89,8 ; z=���2,032 ; p=0,042); varia����o sem sentidos diferentes, com agravamento significativo no grupo ASBREnP no item esta����o de p�� do SPPB (ASBREP 3,8/3,9 p=n.s.; ASBREnP 3,9/3,6; z=���2,236 ; p=0,025); tend��ncia �� melhoria nos dois grupos no MMS (ASBREP: 27,2 / 28,2 ; p=n.s.; ASBREnP: 26,3 / 27,7 ; z=���2,413 ; p=0,016) e tend��ncia em sentidos diferentes no Trail Making, com eventual melhoria no grupo ASBREP (113,9 / 91,6 ; p=n.s.) e agravamento no grupo ASBREnP (113,7 / 152,0 ; z=���2,155 ; p=0,031). Na an��lise da imagem, utilizando a escala ARWMC e o estudo dos CDA, na avalia����o transversal na inclus��o, a compara����o entre as pontua����es m��dias da escala ARWML nas diferentes regi��es mostrava diferen��as significativas (F=39,54 , p<0,0001). A an��lise comparativa post���hoc de Bonferroni mostrou valores significativamente mais altos para as regi��es frontais e parieto���occipitais (p<0,0001). Os valores m��dios dos CDA eram significativamente diferentes entre regi��es (F=44,56; p<0,0001), sendo mais altos na SBFL (p<0,0001). N��o existia diferen��a significativa entre os valores registados na SBAN nas regi��es frontais e parieto���occipitais. As pontua����es regionais da escala ARWMC e os valores m��dios dos CDA correlacionavam���se todos de forma positiva. A pontua����o da escala ARWMC na regi��o frontal correlacionava���se significativamente com os valores do CDA da SBFL (r=0,467 ; p=0,012). Existia tend��ncia para uma correla����o positiva entre as pontua����es da escala ARWMC na regi��o frontal e os valores m��dios dos CDA na SBAN frontal (r=0,276 ; p=0,155). As pontua����es da escala ARWMC e os CDA correlacionavam���se de forma positiva com a idade e com a tens��o arterial (TA). Foram encontradas correla����es significativas entre: idade e SBAN frontal (r=0,440 ; p=0,019); TA diast��lica e SBFL (r=0,386 ; p=0,034); TA sist��lica e SBAN Parieto���occipital (r=0,407 ; P=0,032). Na avalia����o motora e cognitiva, dado elevado n��mero de vari��veis, foi efectuada uma an��lise de factor principal. Registou���se uma tend��ncia global negativa na correla����o entre as pontua����es da escala visual na regi��o frontal, os valores dos CDA, e o desempenho motor e cognitivo. Na an��lise evolutiva, (n=19), registou���se varia����o significativa dos CDA, com aumento na SBFL (Direita: z=���2,875 ; p=0,004 ; Esquerda: z=���2,113 ; p=0,035) e diminui����o na SBAN dos ped��nculos cerebelosos (Direita: z=���2,094 ; p=0,036 ; Esquerda: z=���1,989 ; p=0,047). Foi observada uma correla����o negativa entre a varia����o do CDA na SBAN dos ped��nculos cerebelosos e na SBFL contralateral (SBAN ped��nculo cerebeloso Esquerdo / SBFL Direita: r=���0,133 ; p=n.s.; SBAN ped��nculo cerebeloso Direito / SBFL Esquerda: r=���0,561 ; p=0,012). Os valores dos CDA �� direita correlacionavam���se de forma positiva com a velocidade da marcha (r=0,562 ; p=0,012). CONCLUS��ES: A progress��o das ASBRE pode ser observada com uma escala visual detalhada no intervalo de um ano. Contudo, o eventual agravamento da incapacidade funcional, motora e cognitiva, n��o parece ser apreci��vel em igual intervalo de tempo. A maior severidade das ASBRE associa���se a uma tend��ncia para um maior compromisso funcional, motor e possivelmente do humor. A quest��o da progress��o em escalas simplificadas, de um est��dio ligeiro para um est��dio moderado a grave, n��o �� elucidada pelos resultados do presente trabalho. Os doentes com um envolvimento preferencial da regi��o parieto���occipital poder��o constituir um subgrupo distinto que, apesar de ter maior extens��o de les��o, parece ter um melhor desempenho motor e cognitivo. O perfil evolutivo destes doentes parece igualmente ser distinto, n��o se observando a tend��ncia ao agravamento funcional, motor e cognitivo (sobretudo em provas de fun����o executiva) que se encontra nos restantes doentes. A an��lise transversal na inclus��o, utilizando uma escala visual e o estudo dos CDA, sugere que a severidade das ASBRE se correlaciona com o compromisso motor e cognitivo, bem como com a idade e com a TA. Uma maior vulnerabilidade da subst��ncia branca frontal �� les��o vascular parece ter um papel importante no compromisso motor e na disfun����o executiva, (essencialmente �� custa do compromisso da aten����o), possivelmente associada �� desconex��o dos circuitos fronto���subcorticais. A an��lise dos CDA sugere que isso �� v��lido igualmente para a SBAN e sublinha que, as imagens de RM convencional poder��o n��o traduzir a verdadeira extens��o da les��o e consequentemente do compromisso motor e cognitivo. A rela����o entre a progress��o da doen��a vascular em les��es frontais constitu��das e a redu����o do CDA no ped��nculo cerebeloso contralateral poder�� estar associada a um pior desempenho motor. A disrup����o dos circuitos fronto���cerebelosos, determinando hipometabolismo e diminui����o da perfus��o no cerebelo, poder�� ser respons��vel pela diminui����o do CDA no cerebelo. ABSTRACT INTRODUCTION: Previous studies, with new imaging techniques, have consistently documented the presence of age���related white matter lesions (ARWML), emphasizing their role in agerelated functional decline, mainly related to motor and cognitive impairment, and inherent consequences in clinical practice. However clinical significance of ARWML remains to be elucidated, probably on account of methodological difficulties such as: specific neuropsychological batteries, utilization of samples with different degrees of severity and regional involvement, utilization of different imaging scales and different sensitivity of imaging techniques. Recently, Diffusion Weighted Magnetic Ressonance imaging (DWI) has shown a higher sensitivity to ischemic lesions, suggesting it might be superior for characterization of ARWML, allowing more precise correlation with motor and cognitive variables, and evaluating also normal appearing white matter (NAWM). OBJECTIVES: To describe imagiologic evolution of ARWML within one year interval and to analyse its clinical and functional significance. To identify predictors of ARWML progression and associated functional impairment. To describe clinical characteristics and evolution profile of patients with predominantly posterior lesions; to compare this group of patients with patients without predominantly posterior lesions. To study average Apparent Diffusion Coeficcients (ADC) in different white matter regions using regions of interest (ROI); to analyse their evolution profile and to determine their clinical and imagiologic correlations. METHODS: A sample of 30 patients older than 65 years, without functional impairment or with minimal impairment, according to the Instrumental Activities of Daily Lliving scale, with ARWML on CT scan, were studied in a cross���sectional design. An extensive clinical(with detailed motor and cognitive evaluation) and imagiologic protocol was applied in two one���year interval separate moments (t0 and t1). ARWML were studied using visual scales, ARWMC and Fazekas���s scale, and patients were studied according to degree of severity (Fazekas scale mild versus moderate / severe) and preferential involvement of the posterior region (defined as 2 or more points in the ARWMC scale in the parietooccipital region compared with frontal region). Evaluation of ADC was performed using ROI in frontal lesioned white matter (FLWM) and NAWM (frontal, parieto���occipital and cerebellar regions). To study differences in the distribution of variables the Mann���Whitney test was used and to compare proportions the exact Fisher Test was used. To compare temporal evolution profile between t0 and t1, the Wilcoxon Signed ranks Test was used to analyse the distribution of variables and the Mc Nemar Test to analyse frequencies. Correlation analysis was performed using Spearman or Pearson tests. The study was approved by the local Ethics Committee and all patients signed an informed consent. RESULTS: Mean age was 72.5 years (17 patients were male). By the end of the study, one patient was dead and 3 patients did not undergo brain imaging. There was a higher extent of ARWML evaluated with the ARWMC scale (t0: 8.37 / t1: 9.65 ; p<0.001). Functional, motor and cognitive performance did not progress significantly. Evaluating patients in t0 and t1 according to the degree of severity (Fazekas scale), the moderate / severe group of patients (WML2), compared with the mild group (WML1), showed: higher extent of lesion (ARWMC scale t0: 11.9 / 4.8 ; p<0.001 ; t1: 14.0 / 5.9 ; p<0.001); tendency to worse functional (IADL t0: 90.7 / 99.2 ; p=0.023; t1: 86.4 / 96.7 ; p=n.s.) and motor (SPPB t0: 9.8 / 10.3 ; p=n.s. ; t1: 9.5 / 10.5 ; p=0.058) performance; tendency to higher depressive scores (Cornell Scale t0: 6.7 / 3.5 ; p=0.037; t1: 6.2 / 4.5; p=n.s.). Analysing the evolution profile from t0 to t1 of each group (WML2 and WML1), there was a higher extent of lesion (ARWMC scale) in both (WML2: 12.0 / 14.0; z=���2.687 ; p=0.007; WML1: 4.8 / 5.9 ; z=���2.724 ; p=0.006); non���significant variation in functional and motor performances; tendency to worse performance on the Digit Cancelling (WML2: 17.5 / 17.4 ; p=n.s. ; WML1: 19.9 / 16.9 ; z=���2.096 ; p=0,036) and to better performance on the MMS (WML2: 25.7 / 27.5 ; z=���2.155 ; p=0.031; WML1: 27.5/ 28.2 ; p=n.s). Evaluating patients in t0 and t1 according to the regional distribution of ARWML, patients with predominantly posterior lesions (WMLP) compared with the rest of the group (WMLnP), showed: higher extent of lesion (ARWMC scale t0: 10.8 / 6.9 ; p=0.025; t1:12.9 / 7.6 ; p=0.011); non significant differences on motor evaluation; tendency to a better performance on Maze (t0: 8.1 / 11.8 ; p=0.06; t1: 8.7 / 9.5 ; p=n.s.) and Digit cancelling (t0: 20.9 / 17.4 ; p=0.045; t1: 18.5 / 16.3 ; p=n.s.) tests;tendency to higher scores on GDS (t0: 5.0 / 3.68 ; p=n.s. ; t1: 5.7 / 3.3 p=0.033). Analysing the evolution profile from t0 to t1 of each group (WMLP and WMLnP), there was: higher extent of lesion (ARWMC scale) in both groups (WMLP: 10.8 / 12.9 ;z=���2,555 ; P=0,011; WMLnP: 6.4 / 7.6 ; z=���2.877; p=0.04); variation in different directions with better functional performance in the group WMLP (91.0 / 95.5 ;z=���0.926 ; p=0.036) and worse in WMLnP (96.7 / 89.8 ; z=���2.032 ; p=0.042); variation in different directions with worse motor performance in one SPPB item (total stands) in the group WMLnP (WMLP 3.8/3.9 p=n.s.; ASBREnP 3.9/3.6; z=���2.236 ; p=0.025);tendency to improvement in both groups in MMS (WMLP: 27.2 / 28.2 ; p=n.s.; WMLnP:26.3 / 27.7 ; z=���2.413 ; p=0.016); tendency to a variation in different directions in the Trail Making Test, with possible improvement in the group WMLP (113.9 / 91.6 ;p=n.s.) and worsening in the group WMLnP (113.7 / 152.0 ; z=���2.155 ; p=0.031). Imaging analysis in the inclusion, using the ARWMC scale and ADC evaluation, showed significant differences in different regions (F=39.54, p<0.0001). Comparative post���hoc Bonferroni analysis showed significantly higher scores in the frontal and parieto���occipital regions (p<0.0001. ADC values were significantly different between regions (F=44.56; p<0.0001), being higher in FLWM (p<0���0001). There was no significant difference between ADC in NAWM in frontal and parieto���occipital regions. ARWMC scores and ADC values correlated positively. Significant correlations were found between frontal ARWMC score and FLWM ADC values (r=0.467 ; p=0.012). ARWMC scores and ADC values correlated positively with age and blood pressure. Significant correlations were: age and frontal NAWM (r=0.440 ; p=0.019); Diastolic blood pressure and FLWM (r=0.386 ; p=0.034); sistolic blood pressure and parietooccipital NAWM (r=0.407 ; P=0.032). Due to the higher number of motor and cognitive variables a preliminary study was done, using principal component analysis. A global tendency to a negative correlation was found between ARWMC scores, ADC values and motor and cognitive performances. Evolutive analysis of ADC (n=19), showed a significant variation, with higher values in t1 in FLWM (Right: z=���2.875 ; p=0.004 ; Left: z=���2.113 ; p=0.035) and lower values in t1 in cerebellar NAWM (Right: z=���2.094 ; p=0.036 ; Left: z=���1.989 ; p=0.047). A negative correlation was found between ADC variation in cerebellar NAWM and contralateral FLWM (Left cerebellar NAWM / Right FLWM: r=���0.133 ; p=n.s.; Right cerebellar NAWM/ Left FLWM: r=���0.561 ; p=0.012). ADC values on the right correlated positively with walking speed (r=0,562 ; p=0,012). CONCLUSIONS: Progression of ARWML can be documented with a detailed visual scale in a one year interval. However, functional, motor and cognitive impairment, do not seem to progress significantly within the same period. A higher severity of ARWML is associated with a tendency to a worse functional and motor performance (and possibly to higher scores in depression scales). The issue of progression in a simplified visual scale from a mild to a moderate / severe degree of ARWML is not further elucidated. Patients with predominantly posterior lesions may be a subset of ARWML patients, with a different profile, that despite higher extent of lesion, seem to fair better than the rest of the group, namely with better performance on motor and cognitive tests. Evolution profile of this subset of patients also seems to be different, without a clearcut tendency to worsening functional, motor and cognitive (particularly for executive function tests) performance that is observed in the rest of the group. Imaging analysis, with a visual scale and ADC evaluation, suggests that severity of ARWML correlates negatively with cognitive and motor performance and positively with age and blood pressure. A higher vulnerability of frontal white matter to vascular disease seems to play an important role in motor and cognitive dysfunction, mainly determined by impairment of attention skills associated with frontal���subcortical disconnection. DWI results, suggest that this may also be true for NAWM, underlining that conventional MR images may not represent the true extent of cognitive decline. The relation between vascular disease progression inside frontal lesions and ADC reduction in contralateral cerebellar peduncles, may be associated with a worse motor performance. Disruption of fronto���cerebellar cicuits, with associated regional hypometabolism, may be responsible for the reduction of cerebellar ADC.

Phytoplankton analysis of portuguese reservoirs: a cluster analysis with R

In this work, cluster analysis is applied to a real dataset of biological features of several Portuguese reservoirs. All the statistical analysis is done using R statistical software. Several metrics and methods were explored, as well as the combination of Euclidean metric and the hierarchical Ward method. Although it did not present the best combination in terms of internal and stability validation, it was still a good solution and presented good results in terms of interpretation of the problem at hand.

Processos Colaborativos e de Comunica����o

Esta tese descreve um projeto desenvolvido na sua maioria durante o segundo semestre do ano letivo 2013/2014 nas instala����es da Bosch Security Systems ST em Ovar, uma empresa do Grupo Bosch. Este projeto resultou de uma coopera����o existente entre a Avans University of Applied Sciences (AUAS) e o Instituto Superior de Engenharia do Porto (ISEP), bem como entre a f��brica Bosch ST Ovar e o Centro de Desenvolvimento Bosch situado em Eindhoven, Holanda. O objetivo �� o estudo dos processos colaborativos de comunica����o que se realizam entre a R&D (Research and Development/Centro de Desenvolvimento) e a MP (Manufacturing Plant/F��brica). O sucesso das organiza����es empresariais s�� �� poss��vel se se alcan��ar a satisfa����o das expectativas do mercado. Assim, para o sucesso de uma empresa, temos de ter em conta a sua efici��ncia para conseguir obter o m��ximo rendimento da sua miss��o, que s�� �� poss��vel atrav��s de comunica����es e de processos produtivos/servi��os que acrescentem valor ao bem que disponibilizam. Tendo sempre em vista este princ��pio, o Grupo Bosch tem vindo a adotar metodologias com o intuito de eliminar os desperd��cios existentes nos seus neg��cios aumentando o m��ximo poss��vel os seus rendimentos. O desafio foi encontrar problemas ou dificuldades que levam com que a comunica����o n��o seja realizada eficazmente, o que origina, na maioria dos casos, atrasos nos projetos realizados nesta parceria. Com a orienta����o do diretor t��cnico da f��brica e observando o trabalho realizado por 2 MBI���s (Manufacturing Business Interface), iniciou-se a compreens��o do meio e os m��todos de trabalho da empresa, a forma como �� que �� feita a parceria com os centros de desenvolvimento, como tamb��m as responsabilidades e fun����es de cada um. O estudo desenvolvido teve como base a metodologia Soft Systems Methodology com envolvimento de um question��rio submetido aos colaboradores Bosch, realizando-se no final as sugest��es de melhoria. Este relat��rio apresenta assim o estudo dos processos colaborativos e de comunica����o entre a f��brica e o centro de desenvolvimento.

A influ��ncia do modelo pedag��gico em vari��veis psicol��gicas de estudantes do 1�� ano da ESTSP-IPP

Introdu����o ��� A adapta����o ao ensino superior reveste-se de experi��ncias acad��micas que podem constituir fonte de stress para os estudantes. A implementa����o de novos modelos pedag��gicos, no ��mbito do processo de Bolonha, introduz novas vari��veis cujo impacto, designadamente em termos de sa��de, importa conhecer. Este estudo tem como objetivo analisar as associa����es entre modelo pedag��gico (Problem Based Learning ��� PBL vs. modelos pr��ximos do tradicional) e vari��veis psicol��gicas (coping, desregula����o emocional, sintomas psicossom��ticos, perce����o de stress e afeto). Metodologia ��� O estudo tem um design transversal. Foram usados os seguintes question��rios online: Brief-COPE, Escala de Dificuldades de Regula����o Emocional, Question��rio de Manifesta����es F��sicas de Mal-Estar, Escala de Stress Percebido e Escala de Afeto Positivo e Negativo. A amostra �� constitu��da por 183 estudantes do primeiro ano (84% do g��nero feminino) de cursos da Escola Superior de Tecnologia da Sa��de do Porto ��� Instituto Polit��cnico do Porto (ESTSP-IPP). Resultados ��� Foram encontradas correla����es significativas entre as vari��veis demogr��ficas e psicol��gicas. Considerando diferentes modelos pedag��gicos, foram encontradas diferen��as significativas nas vari��veis psicol��gicas. Os principais preditores de stress na amostra foram: ser mulher, frequentar uma licenciatura no modelo PBL, ter maiores ��ndices de desregula����o emocional, apresentar mais sintomas psicossom��ticos, menos afeto positivo e mais afeto negativo. Conclus��o ��� As diferen��as encontradas entre modelos pedag��gicos s��o discutidas, possibilitando a reflex��o sobre as implica����es pr��ticas e sugest��es para futuras investiga����es.

Calculating rabies virus neutralizing antibodies titres by flow cytometry

The determination of the rabies neutralizing antibody (VNA) response after immunization against rabies is an acceptable index of the efficacy of a vaccine and a successful treatment. Several tests have been developed in attempt to improve the assessment of VNA, from mice inoculation to cell-culture fluorescence inhibition tests. All of them, however, present special difficulties in terms of reading or accuracy. The present study describes a neutralization test performed in cell-culture appraised by flow cytometry (FC). Serial dilutions of the serum samples were mixed in vitro with rabies virus before the addition of BHK-21 cells. After 24h-incubation, cells were released by trypsin treatment, fixed and permeabilized with a p-formaldehyde solution and stained with a rabies virus nucleocapsid protein-specific antibody conjugate. The percentage of virus infection inhibition caused by specific antibodies present in the serum were evaluated in a Beckton &amp; Dickinson FACSCalibur�� flow cytometer. A correlation curve between the IU/ml content and the percentage of infective inhibition was built with a reference serum and the VNA titers of serum samples were obtained by extrapolation. Titers obtained by FC and standard test showed an effective pairing results (p < 0.01), with a correlation coefficient (r) = 0.7. These results permit to envisage the FC as a suitable technique to evaluate VNA in sera from immunized animals and likely in human serum samples. Nevertheless, new studies comparing FC to gold-standard techniques are required for determining the FC values of Sensibility and Specificity .

The role of ribonuclease R in bacterial adaptation to cold shock

RESUMO:Os microrganismos reagem �� s��bita descida de temperatura atrav��s de uma resposta adaptativa espec��fica que assegura a sua sobreviv��ncia em condi����es desfavor��veis. Esta adapta����o inclui altera����es na composi����o da membrana, na maquinaria de tradu����o e transcri����o. A resposta ao choque t��rmico pelo frio induz uma repress��o da transcri����o. No entanto, a descida de temperatura induz a produ����o de um grupo de prote��nas espec��ficas que ajudam a ajustar/re-ajustar o metabolismo celular ��s novas condi����es ambientais. Em E. coli o processo de adapta����o demora apenas quatro horas, no qual um grupo de prote��nas espec��ficas s��o induzidas. Depois desde per��odo recome��a lentamente a produ����o de prote��nas.A ribonuclease R, uma das prote��nas induzidas durante o choque t��rmico pelo frio, �� uma das principais ribonucleases em E. coli envolvidas na degrada����o do RNA. �� uma exoribonuclease que degrada RNA de cadeia dupla, possui fun����es importantes na matura����o e ���turnover��� do RNA, liberta����o de ribossomas e controlo de qualidade de prote��nas e RNAs. O n��vel celular desta enzima aumenta at�� dez vezes ap��s exposi����o ao frio e estabiliza em c��lulas na fase estacion��ria. A capacidade de degradar RNA de dupla cadeia �� importante a baixas temperaturas quando as estruturas de RNA est��o mais est��veis. No entanto, este mecanismo �� desconhecido. Embora a resposta espec��fica ao ���cold shock��� tenha sido descoberta h�� mais de duas d��cadas e o n��mero de prote��nas envolvidas sugerirem que esta adapta����o �� r��pida e simples, continuamos longe de compreender este processo. No nosso trabalho pretendemos descobrir prote��nas que interactuem com a RNase R em condi����es ambientais diferentes atrav��s do m��todo ���TAP-tag��� e espectrometria de massa. A informa����o obtida pode ser utilizada para deduzir algumas das novas fun����es da RNase R durante a adapta����o bacteriana ao frio e durante a fase estacion��ria. Mais importante ainda, RNase R poder�� ser recrutada para um complexo de prote��nas de elevado peso molecular durante o ���cold-shock���.------------ABSTRACT:Microorganisms react to the rapid temperature downshift with a specific adaptative response that ensures their survival in unfavorable conditions. Adaptation includes changes in membrane composition, in translation and transcription machinery. Cold shock response leads to overall repression of translation. However, temperature downshift induces production of a set of specific proteins that help to tune cell metabolism and readjust it to the new environmental conditions. For Escherichia coli the adaptation process takes only about four hours with a relatively small set of specifically induced proteins involved. After this time, protein production resumes, although at a slower rate. One of the cold inducible proteins is RNase R, one of the main E. coli ribonucleases involved in RNA degradation. RNase R is an exoribonuclease that digest double stranded RNA, serves important functions in RNA maturation and turnover, release of stalled ribosomes by trans-translation, and RNA and protein quality control. The level of this enzyme increases about ten-fold after cold induction, and it is also stabilised in cells growing in stationary phase. The RNase R ability to digest structured RNA is important at low temperatures where RNA structures are stabilized but the exact role of this mechanism remains unclear. Although specific bacterial cold shock response was discovered over two decades ago and the number of proteins involved suggests that this adaptation is fast and simple, we are still far from understanding this process. In our work we aimed to discover the proteins interacting with RNase R in different environmental conditions using TAP tag method and mass spectrometry analysis. The information obtained can be used to deduce some of the new functions of RNase R during adaptation of bacteria to cold and in stationary growth phase. Most importantly RNase R can be recruited into a high molecular mass complex of protein in cold shock.

Fluxus: do texto �� ac����o. A cartografia de uma a(r)titude

Trabalho de Projecto em Ci��ncias da Comunica����o, variante Cultura Contempor��nea e Novas Tecnologias

Atividade tradutol��gica: a (r)evolu����o dos ��ltimos 20 anos

Trabalho de natureza profissional para a atribui����o do T��tulo de Especialista do Instituto Polit��cnico do Porto, na ��rea de L��nguas e Cuturas - L��nguas e Literaturas Estrangeiras, defendido a 11-11-2015.

Difficulties in the diagnosis of HTLV-2 infection in HIV/AIDS patients from Brazil: comparative performances of serologic and molecular assays, and detection of HTLV-2b subtype

The current diagnosis of human T-lymphotropic virus type-2 (HTLV-2) infection is based on the search of specific antibodies; nevertheless, several studies conducted in Brazil pointed deficiencies of the commercially available kits in detecting HTLV-2, mostly in HIV/AIDS patients. This study searched for the presence of HTLV-1 and -2 in 758 HIV/AIDS patients from Londrina, Paran��, Brazil. Serum samples were screened for HTLV-1/2 antibodies using two EIA kits (Vironostika and Murex), and confirmed by WB (HTLV Blot 2.4, Genelabs). The results obtained by EIA disclosed 49 (6.5%) reactive sera: 43 positive by both EIA kits, and six with discordant results. WB confirmed HTLV-1 infection in seven samples (0.9%) and HTLV-2 in 21 sera (2.8%). Negative and indeterminate results were detected in four (0.5%) and 16 (2.1%) sera, respectively. Blood from 47 out of 49 HTLV seroreactive patients were collected and analyzed for the presence of env, LTR and tax genomic segments of HTLVs by PCR. PCR confirmed six cases of HTLV-1 and 37 cases of HTLV-2 infection (14 out of 16 that were found to be WB indeterminate). Restriction analysis of the env PCR products of HTLV-2 disclosed 36 isolates of HTLV-2a/c subtype, and one of HTLV-2b subtype. These results emphasize the need of improving serologic tests for detecting truly HTLV-2 infected patients from Brazil, and confirm the presence of HTLV-2b subtype in the South of this country.

Stochasticity favoring the effects of the R&D strategies of the firms

We present stochastic dynamics on the production costs of Cournot competitions, based on perfect Nash equilibria of nonlinear R&D investment strategies to reduce the production costs of the firms at every period of the game. We analyse the effects that the R&D investment strategies can have in the profits of the firms along the time. We observe that, in certain cases, the uncertainty can improve the effects of the R&D strategies in the profits of the firms due to the non-linearity of the profit functions and also of the R&D parameters.

Cournot duopoly with competition in the R&D expenditures

We present a new R&D investment in a Cournot Duopoly model and we analyze the different possible types of Nash R&D investments. We observe that the new production costs region can be decomposed in three economical regions, depending on the Nash R&D investment, showing the relevance of the use of patents in new technologies.

Toxicity of saponin isolated from Gymnema sylvestre R. Br. (Asclepiadaceae) against Culex tritaeniorhynchus Giles (Diptera: Culicidae) Japanese encephalitis vector mosquito in India

To determine the larvicidal activity of various extracts of Gymnema sylvestre against the Japanese Encephalitis vector, Culex tritaeniorynchus in Tamilnadu, India. To identify the active principle present in the promising fraction obtained in Chlorofom:Methanol extract of Fraction 2. The G. sylvestre leaf extracts were tested, employing WHO procedure against fourth instar larvae of C. tritaeniorhynchus and the larval mortalities were recorded at various concentrations (6.25, 12.5, 25.0, 50 and 100 ��g/mL); the 24h LC50 values of the G. Sylvestre leaf extracts were determined following Probit analysis. It was noteworthy that treatment level 100 ��g/mL exhibited highest mortality rates for the three different crude extracts and was significantly different from the mean mortalities recorded for the other concentrations. The LC50 values of 34.756 ��g/mL (24.475-51.41), 31.351 ��g/mL (20.634-47.043) and 28.577 ��g/mL (25.159-32.308) were calculated for acetone, chloroform and methanol extract with the chi-square values of 10.301, 31.351 and 4.093 respectively. The present investigation proved that G. Sylvestre could be possibly utilized as an important component in the Vector Control Program.

Rickettsia typhi IN RODENTS AND R. felis IN FLEAS IN YUCAT&#193;N AS A POSSIBLE CAUSAL AGENT OF UNDEFINED FEBRILE CASES

Rickettsia typhi is the causal agent of murine typhus; a worldwide zoonotic and vector-borne infectious disease, commonly associated with the presence of domestic and wild rodents. Human cases of murine typhus in the state of Yucat&#225;n are frequent. However, there is no evidence of the presence of Rickettsia typhi in mammals or vectors in Yucat&#225;n. The presence of Rickettsia in rodents and their ectoparasites was evaluated in a small municipality of Yucat&#225;n using the conventional polymerase chain reaction technique and sequencing. The study only identified the presence of Rickettsia typhi in blood samples obtained from Rattus rattus and it reported, for the first time, the presence of R. felis in the flea Polygenis odiosus collected from Ototylomys phyllotis rodent. Additionally, Rickettsia felis was detected in the ectoparasite Ctenocephalides felis fleas parasitizing the wild rodent Peromyscus yucatanicus. This study&#8217;s results contributed to a better knowledge of Rickettsia epidemiology in Yucat&#225;n.

Studies on BolA and ribonuclease R: two important factors in the control of bacterial gene expression

Dissertation presented to obtain the Ph.D degree in Biology