HB - Patologia Clínica
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- Candida clinical species identification: molecular and biochemical methodsPublication . Costa, AR; Silva, F; Henriques, M; Azeredo, J; Oliveira, R; Faustino, AIn the last decade, the number and diversity of nosocomial Candida infections has increased significantly, resulting in an emergent need for rapid and accurate methods for Candida identification. Therefore, the aim of this study was to evaluate the performance of three biochemical systems (Auxacolor, ID32C, and Vitek 2 YST) for the identification of Candida species, comparing them with molecular identification (polymerase chain reaction and gel agarose electrophoresis). These methods were used to assess Candida spp. (229 clinical isolates) prevalence and distribution among clinical specimens. The biochemical methods with higher percentages of correct identification were Vitek 2 YST (79.6%) and Auxacolor (78.6%). However, overall the biochemical methods assayed differed from the molecular identification. Thus, due to their rapid and precise identification, molecular methods are promising techniques for Candida species identification in clinical laboratories. Candida albicans and Non Candida albicans Candida species had a similar prevalence (50.4 and 49.6%, respectively), corroborating the epidemiological shift observed for these pathogens in the recent years.
- Determinantes da colonização materna e da infecção neonatal por Streptococcus do grupo BPublication . Areal, A; Moreira, M; Nunes, S; Faustino, MA; Cardoso, L; Sá, CAim and Objective: During the past three decades, group B Streptococcus (GBS) neonatal infection has been the subject of little research. The aim of this study was to evaluate the association between maternal risk factors, as established by the Center for Disease Control and Prevention (CDC), and maternal colonization. We also analysed the association between risk factors present in newborns and early-onset GBS disease. Study design: Cross-sectional study. Population: All pregnant women admitted for delivery in our institution and their newborns, between 1st February and 31st July 2005. Methods: Maternal and neonatal characteristics were collected from hospital clinical data, including information on risk factors established by the CDC. Descriptive statistics was used to characterize the study sample. Qui-square and Mantel-haenszel tests were applied to compare proportions and to measure the strength of associations, respectively, setting significance at p < 0,05. Results: In this sample only 47% of women were screened for GBS colonization in suitable time and 34,9% of these women were colonized. The incidence of early neonatal infection by SGB was 9/1000 neonates. Significant associations between GBS maternal colonization ant the following parameters were observed: maternal age [p=0,012; OR=1,659 (IC a 95%, 1,218-2,260)], gestational age at labour [p=0,001; OR= 2,621 (IC a 95%, 1,641- 4,188)], and urinary GBS infection during pregnancy (p<0,001). Maternal colonization occurred in women without CDC defined risk factors. Early neonatal infection by SGB was strongly associated with unscreened women (p=0,014). Conclusion: In this study, maternal GBS colonization occurred in the absence of CDC defined risk factors and varied according to maternal age and gestational week. Neonatal GBS infection was more frequent in unscreened women.
- Draft genome sequences of two Pseudomonas aeruginosa clinical isolates with different antibiotic susceptibilitiesPublication . Soares-Castro, P; Marques, D; Demyanchuck, S; Faustino, A; Santos, PMPseudomonas aeruginosa is a primary cause of opportunistic infections. We have sequenced and annotated the genomes of two P. aeruginosa clinical isolates evidencing different antibiotic susceptibilities. Registered differences in the composition of their accessory genomes may provide clues on P. aeruginosa strategies to thrive in different environments like infection loci.
- Efficacy of a broad host range lytic bacteriophage against E. coli adhered to urotheliumPublication . Sillankorva, S; Oliveira, D; Moura, A; Henriques, M; Faustino, A; Nicolau, A; Azeredo, JPersistent urinary tract infections (UTI) are often caused by E. coli adhered to urothelium. This type of cells is generally recognized as very tolerant to antibiotics which renders difficult the treatment of chronic UTI. This study investigates the use of lytic bacteriophages as alternative antimicrobial agents, particularly the interaction of phages with E. coli adhered to urothelium and specifically determines their efficiency against this type of cells. The bacterial adhesion to urothelium was performed varying the bacterial cell concentrations and the period and conditions (static, shaken) of adhesion. Three collection bacteriophages (T1, T4, and phiX174 like phages) were tested against clinical E. coli isolates and only one was selected for further infection experiments. Based on the lytic spectrum against clinical isolates and its ability to infect the highest number of antibiotic resistant strains, the T1-like bacteriophage was selected. This bacteriophage caused nearly a 45% reduction of the bacterial population after 2 h of treatment. This study provides evidence that bacteriophages are effective in controlling suspended and adhered cells and therefore can be a viable alternative to antibiotics to control urothelium- adhered bacteria.
- Esophagocoloplasty in Esophageal Cancer Associated with Synchronous GastricPublication . Leão, P; Carneiro, T; Luís, D; Campelos, S; Gomes, A
- Etiology of bronchiolitis in a hospitalized pediatric population: prospective multicenter studyPublication . Antunes, H; Rodrigues, H; Silva, N; Ferreira, C; Carvalho, F; Ramalho, H; Gonçalves, A; Branca, FBACKGROUND: In 2006, bronchiolitis due to adenovirus nosocomial infections resulted in the closure of a pediatric department in northern Portugal. OBJECTIVES: To determine the etiology of bronchiolitis in northern Portugal. STUDY DESIGN: It was a prospective multicenter study on the etiology of bronchiolitis during the respiratory syncytial virus (RSV) season (November-April). Children < or = 24 months of age admitted for a first wheezing episode were included. Nasopharyngeal specimens were analyzed by an indirect immunofluorescent-antibody assay (IFA) for RSV, adenovirus (HAdV), parainfluenza (PIV) 1-3 and influenza (IV) A and B and by polymerase chain reaction (PCR) or reverse transcription-PCR for the same viruses and for human metapneumovirus (hMPV), bocavirus (HBoV), rhinovirus (HRV), coronaviruses (229/E; NL63; OC43; HKU1) and enterovirus. RESULTS: During this period, 253 children were included, 249 IFA analyses and 207 PCRs were performed. IFA detected RSV in 58.1%; PCR increased it to 66.7%. IFA detected HAdV in 3.2%, PCR 10.0%. PCR detected IV A in 5; IV B in 2; PIV 1 in 6, PIV 2 in 4 and PIV 3 in 11 cases. HBoV, as single agent in 2 cases, and HRV were positive in 8 samples and hMPV in 11. With this virus panel, 19.7% remained without etiology. CONCLUSIONS: The most frequent agent was RSV, followed by HAdV. PCR can be cost-effective and more accurate than IFA, which is crucial for HAdV that may be associated with significant mortality (IFA alone did not detect 2/3 of the cases).
- G2P[4] the most prevalent rotavirus genotype in 2007 winter season in an European non-vaccinated populationPublication . Antunes, H; Afonso, A; Iturriza, M; Martinho, I; Ribeiro, C; Rocha, S; Magalhães, C; Carvalho, L; Branca, F; Gray, JBACKGROUND: Recently, a high prevalence of G2P[4] rotavirus (RV) infection was reported from Brazil, and linked with the universal RV vaccination programme that used the G1P[8] live oral RV vaccine. OBJECTIVE: To determine the genotypes of RV co-circulating in a non-vaccinated population, in northern Portugal in the winter season of 2007. STUDY DESIGN: Prospective multicenter study of the genotypes circulating in the northwest region of Portugal during January to March 2007. Children with acute gastroenteritis, who attended the Pediatric Emergency Services of five Hospitals, were included in the study. The parents of the children completed a clinical and epidemiological data questionnaire and stool samples were collected. Stool samples positive in a RV enzyme immunoassay (EIA) were genotyped by reverse transcriptase-polymerase chain reaction. RESULTS: Stool samples were collected from 424 children. Two hundred and thirty-four (55.2%) stool samples were RV-positive. G2P[4] was the predominant RV type (68.6%), followed by G9P[8] (14.0%). CONCLUSIONS: Because our population was naïve for RV vaccine, the G2P[4] predominance cannot be explained by vaccination. Rather, this high prevalence of G2P[4] may be within the normal fluctuation of RV genotypes. RV strain surveillance programmes are important for informing RV vaccination programmes.
- Group B streptococcal colonisation in pregnant women: turnaround time of three culture methodsPublication . Areal, A; Faustino, MA
- A infecção peri-natal por Streptococcus agalactiae pode ser evitada: prevalência da colonização em parturientes no Hospital de S. Marcos, factores de risco e sua relação com a infecção peri-natalPublication . Areal, A; Nunes, S; Moreira, M; Faustino, MA; Cardoso, L; Sá, Cntrodução: O Streptococcus agalactiae (SGB) é o agente mais frequente de infecção neonatal precoce, sendo possível a sua prevenção. Em Portugal é desconhecida a prevalência de mulheres colonizadas por SGB. O estudo da Unidade de Vigilância Pediátrica refere uma prevalência nacional de infecção neonatal por SGB de 0,5:1000 nados-vivos. Objectivo: Determinar a prevalência da colonização materna e da infecção perinatal por SGB no Hospital de S. Marcos, Braga (HSM), de modo a avaliar a importância da implementação do rastreio universal e o uso de medidas profiláticas. Método: De 1 de fevereiro a 31 de julho de 2005 foi realizado um estudo transversal com análise de coortes anichada, avaliando todas as grávidas assistidas para trabalho de parto no HSM e respectivos recém-nascidos. Os dados foram submetidos a análise estatística bi-variada pelo teste do qui-quadrado, com um nível de significância de 5% (p<0,05). Resultados: A prevalência da colonização nas grávidas rastreadas na região de Braga foi de 34,9 % [intervalo de confiança a 95% (IC95%), 31,5-38,3%]. No HSM o diagnóstico de infecção neonatal precoce por SGB ocorreu em 9:1000 recém-nascidos. O risco relativo de ocorrência de infecção perinatal entre os recém-nascidos dos grupos de mães rastreadas e não rastreadas foi de 0,3 [IC95% 0,2,7-0,32]. Conclusão: O rastreio bacteriológico positivo para colonização materna por SGB associado à adequada profilaxia intra-parto reduziu significativamente a infecção neonatal precoce, em relação ao grupo de gestantes não rastreadas (p=0,014). Consideramos que é recomendável a instituição do rastreio universal das grávidas e a profilaxia adequada quando indicada.
- mTOR pathway overactivation in BRAF mutated papillary thyroid carcinomaPublication . Faustino, A; Couto, JP; Pópulo, H; Rocha, AS; Pardal, F; Cameselle-Teijeiro, JM; Lopes, JM; Sobrinho-Simões, M; Soares, PCONTEXT: There are several genetic and molecular evidences suggesting dysregulation of the mammalian target of rapamycin (mTOR) pathway in thyroid neoplasia. Activation of the phosphatidylinositol-3-kinase/AKT pathway by RET/PTC and mutant RAS has already been demonstrated, but no data have been reported for the BRAF(V600E) mutation. OBJECTIVE: The aim of this study was to evaluate the activation pattern of the mTOR pathway in malignant thyroid lesions and whether it may be correlated with known genetic alterations, as well as to explore the mechanisms underlying mTOR pathway activation in these neoplasias. RESULTS: We observed, by immunohistochemical evaluation, an up-regulation/activation of the mTOR pathway proteins in thyroid cancer, particularly in conventional papillary thyroid carcinoma (cPTC). Overactivation of the mTOR signaling was particularly evident in cPTC samples harboring the BRAF(V600E) mutation. Transfection assays with BRAF expression vectors as well as BRAF knockdown by small interfering RNA revealed a positive association between BRAF expression and mTOR pathway activation, which appears to be mediated by pLKB1 Ser428, and emerged as a possible mechanism contributing to the association between BRAF mutation and mTOR pathway up-regulation. When we evaluated the rapamycin in the growth of thyroid cancer cell lines, we detected that cell lines with activating mutations in the MAPK pathway show a higher sensitivity to this drug. CONCLUSIONS: We determined that the AKT/mTOR pathway is particularly overactivated in human cPTC harboring the BRAF(V600E) mutation. Moreover, our results suggest that the mTOR pathway could be a good target to enhance therapy effects in certain types of thyroid carcinoma, namely in those harboring the BRAF(V600E) mutation.