PCR colorimetric dot-blot assay and clinical pretest probability for diagnosis of Pulmonary Tuberculosis in Smear-Negative patients

<p>Abstract</p> <p>Background</p> <p>Smear-negative pulmonary tuberculosis (SNPTB) accounts for 30% of Pulmonary Tuberculosis (PTB) cases reported annually in developing nations. Polymerase chain reaction (PCR) may provide an alternative for the rapid detection of <it>Mycobacterium tuberculosis </it>(MTB); however little data are available regarding the clinical utility of PCR in SNPTB, in a setting with a high burden of TB/HIV co-infection.</p> <p>Methods</p> <p>To evaluate the performance of the PCR dot-blot in parallel with pretest probability (Clinical Suspicion) in patients suspected of having SNPTB, a prospective study of 213 individuals with clinical and radiological suspicion of SNPTB was carried out from May 2003 to May 2004, in a TB/HIV reference hospital. Respiratory specialists estimated the pretest probability of active disease into high, intermediate, low categories. Expectorated sputum was examined by direct microscopy (Ziehl-Neelsen staining), culture (Lowenstein Jensen) and PCR dot-blot. Gold standard was based on culture positivity combined with the clinical definition of PTB.</p> <p>Results</p> <p>In smear-negative and HIV subjects, active PTB was diagnosed in 28.4% (43/151) and 42.2% (19/45), respectively. In the high, intermediate and low pretest probability categories active PTB was diagnosed in 67.4% (31/46), 24% (6/25), 7.5% (6/80), respectively. PCR had sensitivity of 65% (CI 95%: 50%–78%) and specificity of 83% (CI 95%: 75%–89%). There was no difference in the sensitivity of PCR in relation to HIV status. PCR sensitivity and specificity among non-previously TB treated and those treated in the past were, respectively: 69%, 43%, 85% and 80%. The high pretest probability, when used as a diagnostic test, had sensitivity of 72% (CI 95%:57%–84%) and specificity of 86% (CI 95%:78%–92%). Using the PCR dot-blot in parallel with high pretest probability as a diagnostic test, sensitivity, specificity, positive and negative predictive values were: 90%, 71%, 75%, and 88%, respectively. Among non-previously TB treated and HIV subjects, this approach had sensitivity, specificity, positive and negative predictive values of 91%, 79%, 81%, 90%, and 90%, 65%, 72%, 88%, respectively.</p> <p>Conclusion</p> <p>PCR dot-blot associated with a high clinical suspicion may provide an important contribution to the diagnosis of SNPTB mainly in patients that have not been previously treated attended at a TB/HIV reference hospital.</p

NKX2.5 is expressed in papillary thyroid carcinomas and regulates differentiation in thyroid cells

Abstract Background NKX2.5 is a transcription factor transiently expressed during thyroid organogenesis. Recently, several works have pointed out the oncogenic role of NKX2.5 in a variety of tumors. We therefore hypothesized that NKX2.5 could also play a role in thyroid cancer. Methods The validation of NKX2.5 expression was assessed by immunohistochemistry analysis in a Brazilian case series of 10 papillary thyroid carcinoma (PTC) patients. Then, the long-term prognostic value of NKX2.5 and its correlation with clinicopathologic features of 51 PTC patients was evaluated in a cohort with 10-years follow-up (1990–1999). Besides, the effect of NKX2.5 overexpression on thyroid differentiation markers and function was also investigated in a non-tumor thyroid cell line (PCCL3). Results NKX2.5 was shown to be expressed in most PTC samples (8/10, case series; 27/51, cohort). Patients who had tumors expressing NKX2.5 showed lower rates of persistence/recurrence (p = 0.013). Overexpression of NKX2.5 in PCCL3 cells led to: 1) downregulation of thyroid differentiation markers (thyrotropin receptor, thyroperoxidase and sodium-iodide symporter); 2) reduced iodide uptake; 3) increased extracellular H2O2 generation, dual oxidase 1 mRNA levels and activity of DuOx1 promoter. Conclusions In summary, NKX2.5 is expressed in most PTC samples analyzed and its presence correlates to better prognosis of PTC. In vitro, NKX2.5 overexpression reduces the expression of thyroid differentiation markers and increases ROS production. Thus, our data suggests that NKX2.5 could play a role in thyroid carcinogenesis

Oral Streptococci Biofilm Formation on Different Implant Surface Topographies

The establishment of the subgingival microbiota is dependent on successive colonization of the implant surface by bacterial species. Different implant surface topographies could influence the bacterial adsorption and therefore jeopardize the implant survival. This study evaluated the biofilm formation capacity of five oral streptococci species on two titanium surface topographies. In vitro biofilm formation was induced on 30 titanium discs divided in two groups: sandblasted acid-etched (SAE- n=15) and as-machined (M- n=15) surface. The specimens were immersed in sterilized whole human unstimulated saliva and then in fresh bacterial culture with five oral streptococci species: Streptococcus sanguinis, Streptococcus salivarius, Streptococcus mutans, Streptococcus sobrinus, and Streptococcus cricetus. The specimens were fixed and stained and the adsorbed dye was measured. Surface characterization was performed by atomic force and scanning electron microscopy. Surface and microbiologic data were analyzed by Student’s t-test and two-way ANOVA, respectively (P<0.05). S. cricetus, S. mutans, and S. sobrinus exhibited higher biofilm formation and no differences were observed between surfaces analyzed within each species (P>0.05). S. sanguinis exhibited similar behavior to form biofilm on both implant surface topographies, while S. salivarius showed the lowest ability to form biofilm. It was concluded that biofilm formation on titanium surfaces depends on surface topography and species involved

Setor e emprego informal no Brasil: análise dos resultados da nova série do sistema de contas nacionais - 2000/07 The informal sector and informal employment in Brazil: an analysis of the results of the new series from the national account system (2000/07)

O objetivo central deste texto é retratar o setor informal brasileiro à luz das novas possibilidades de análise que se constituíram a partir da revisão da série do Sistema de Contas Nacionais (SCN), realizada em 2007. São apresentados os resultados referentes à geração de valor adicionado e ao número de ocupações por setor produtivo e tipo de emprego para o Brasil no período recente, considerando a metodologia revista do novo manual internacional de contas nacionais. A base de dados utilizada foi a nova série do SCN, cujo ano de referência é 2000 e os dados disponíveis compreendem os anos 2000 a 2007. Em 2007, o setor informal, que empregava 27,7% dos postos de trabalho do país, teve uma contribuição de 9,9% na geração do valor adicionado. O emprego informal como um todo, por sua vez, alcançou 56,4% das ocupações totais.<br>The central objective of this paper is to present the informal sector in Brazil in face of new possibilities resulting from the revision of the Brazilian SNA series in 2007. The results concerning the generation of value added and the number of occupations by sector of production and type of employment for Brazil in a recent period, are presented in the study. The SNA new series database was used, where the reference year is 2000 and the available data cover the years 2000 to 2007. In the last year of the series, the informal sector, which accounts for 27.2% of jobs in the country, displayed a contribution of 9.9% in the generation of value added. In turn, informal employment as a whole reached 56.4% of total employment

Tempo de latência e características da nomeação de figuras de crianças com transtorno da leitura Latency time and characteristics of picture labelling by children with reading disorders

O objetivo deste estudo foi investigar o tempo de latência e as características da nomeação de figuras em crianças com Transtorno da Leitura e com desenvolvimento típico de leitura, de mesma escolaridade. As amostras foram constituídas por 20 crianças com Transtorno da Leitura (m=8,3 a) e 25 criançassem dificuldades na leitura (m=8,6 a), de ambos os gêneros. O teste de nomeação de figuras foi constituído por 96 figuras, com balanceamento equivalente às palavras escritas: freqüência de ocorrência, extensão e complexidade para o português falado no Brasil. As figuras foram apresentadas na tela de um computador e as crianças foram instruídas a dizer o nome das figuras. O tempo de latência e as respostas foram registradas em um programa criado especialmente para esta pesquisa. As respostas foram analisadas de acordo com os critérios da literatura específica. Não foram observadas diferenças entre crianças com Transtorno da Leitura e seus controles para o tempo de latência. Todavia os resultados apontaram mais respostas corretas para o grupo de leitores e mais erros fonológicos para as crianças com Transtorno da Leitura. Conclui-se que o tempo gasto para a recuperação dos nomes das figuras é semelhante entre as amostras, porém as crianças com Transtorno da Leitura podem exibir déficits na nomeação de figuras, principalmente para selecionar as formas fonológicas dos nomes, resultando em nomeações incorretas.<br>The aim of this study was to verify latency time and the properties for the picture labelling in children with reading disorders and children with typical reading development. The sample was composed of 20 children with reading disorders (age mean=8,3 y) and 25 children without reading disorders (age mean=8,6 y), from both genders. The picture labelling test was made up of 96 pictures, divided into stimuli groups, with equivalent balance to written words: frequency of occurrence of the written word, word extension and complexity for Portuguese spoken in Brazil. The pictures were presented on a computer screen and children were asked to name the pictures. The latency time and the responses were registered in a program designed specially for this study. The responses were analyzed according to criteria of specific literature. No statistical differences were observed between readers and non-readers related to the processing time, however, results pointed to more correct answers in the reader group. Non-readers have more phonological errors than readers. In conclusion, the latency time is similar between the subjects. However non-readers can show difficulties in picture naming, especially as to selection of phonological properties of the picture naming, which result in errors in labelling