Transcriptional profiling reveals the expression of novel genes in response to various stimuli in the human dermatophyte Trichophyton rubrum

<p>Abstract</p> <p>Background</p> <p>Cutaneous mycoses are common human infections among healthy and immunocompromised hosts, and the anthropophilic fungus <it>Trichophyton rubrum </it>is the most prevalent microorganism isolated from such clinical cases worldwide. The aim of this study was to determine the transcriptional profile of <it>T. rubrum </it>exposed to various stimuli in order to obtain insights into the responses of this pathogen to different environmental challenges. Therefore, we generated an expressed sequence tag (EST) collection by constructing one cDNA library and nine suppression subtractive hybridization libraries.</p> <p>Results</p> <p>The 1388 unigenes identified in this study were functionally classified based on the Munich Information Center for Protein Sequences (MIPS) categories. The identified proteins were involved in transcriptional regulation, cellular defense and stress, protein degradation, signaling, transport, and secretion, among other functions. Analysis of these unigenes revealed 575 <it>T. rubrum </it>sequences that had not been previously deposited in public databases.</p> <p>Conclusion</p> <p>In this study, we identified novel <it>T. rubrum </it>genes that will be useful for ORF prediction in genome sequencing and facilitating functional genome analysis. Annotation of these expressed genes revealed metabolic adaptations of <it>T. rubrum </it>to carbon sources, ambient pH shifts, and various antifungal drugs used in medical practice. Furthermore, challenging <it>T. rubrum </it>with cytotoxic drugs and ambient pH shifts extended our understanding of the molecular events possibly involved in the infectious process and resistance to antifungal drugs.</p

Effect of chloroquine on gene expression of Plasmodium yoelii nigeriensis during its sporogonic development in the mosquito vector

<p>Abstract</p> <p>Background</p> <p>The anti-malarial chloroquine can modulate the outcome of infection during the <it>Plasmodium </it>sporogonic development, interfering with <it>Plasmodium </it>gene expression and subsequently, with transmission. The present study sets to identify <it>Plasmodium </it>genes that might be regulated by chloroquine in the mosquito vector.</p> <p>Methods</p> <p>Differential display RT-PCR (DDRT-PCR) was used to identify genes expressed during the sporogonic cycle that are regulated by exposure to chloroquine. <it>Anopheles stephensi </it>mosquitoes were fed on <it>Plasmodium yoelii nigeriensis</it>-infected mice. Three days post-infection, mosquitoes were fed a non-infectious blood meal from mice treated orally with 50 mg/kg chloroquine. Two differentially expressed <it>Plasmodium </it>transcripts (Pyn_chl091 and Pyn_chl055) were further characterized by DNA sequencing and real-time PCR analysis.</p> <p>Results</p> <p>Both transcripts were represented in <it>Plasmodium </it>EST databases, but displayed no homology with any known genes. Pyn_chl091 was upregulated by day 18 post infection when the mosquito had a second blood meal. However, when the effect of chloroquine on that transcript was investigated during the erythrocytic cycle, no significant differences were observed. Although slightly upregulated by chloroquine exposure the expression of Pyn_chl055 was more affected by development, increasing towards the end of the sporogonic cycle. Transcript abundance of Pyn_chl055 was reduced when erythrocytic stages were treated with chloroquine.</p> <p>Conclusion</p> <p>Chloroquine increased parasite load in mosquito salivary glands and interferes with the expression of at least two <it>Plasmodium </it>genes. The transcripts identified contain putative signal peptides and transmembrane domains suggesting that these proteins, due to their location, are targets of chloroquine (not as an antimalarial) probably through cell trafficking and recycling.</p

MicroRNA expression as risk biomarker of breast cancer metastasis : a pilot retrospective case-cohort study

Background: MicroRNAs (miRNAs) are small, non-coding RNA molecules involved in post-transcriptional gene regulation and have recently been shown to play a role in cancer metastasis. In solid tumors, especially breast cancer, alterations in miRNA expression contribute to cancer pathogenesis, including metastasis. Considering the emerging role of miRNAs in metastasis, the identification of predictive markers is necessary to further the understanding of stage-specific breast cancer development. This is a retrospective analysis that aimed to identify molecular biomarkers related to distant breast cancer metastasis development. Methods: A retrospective case cohort study was performed in 64 breast cancer patients treated during the period from 1998-2001. The case group (n = 29) consisted of patients with a poor prognosis who presented with breast cancer recurrence or metastasis during follow up. The control group (n = 35) consisted of patients with a good prognosis who did not develop breast cancer recurrence or metastasis. These patient groups were stratified according to TNM clinical stage (CS) I, II and III, and the main clinical features of the patients were homogeneous. MicroRNA profiling was performed and biomarkers related to metastatic were identified independent of clinical stage. Finally, a hazard risk analysis of these biomarkers was performed to evaluate their relation to metastatic potential. Results: MiRNA expression profiling identified several miRNAs that were both specific and shared across all clinical stages (p <= 0.05). Among these, we identified miRNAs previously associated with cell motility (let-7 family) and distant metastasis (hsa-miR-21). In addition, hsa-miR-494 and hsa-miR-21 were deregulated in metastatic cases of CSI and CSII. Furthermore, metastatic miRNAs shared across all clinical stages did not present high sensitivity and specificity when compared to specific-CS miRNAs. Between them, hsa-miR-183 was the most significative of CSII, which miRNAs combination for CSII (hsa-miR-494, hsa-miR-183 and hsa-miR-21) was significant and were a more effective risk marker compared to the single miRNAs. Conclusions: Women with metastatic breast cancer, especially CSII, presented up-regulated levels of miR-183, miR-494 and miR-21, which were associated with a poor prognosis. These miRNAs therefore represent new risk biomarkers of breast cancer metastasis and may be useful for future targeted therapies.We thank the Researcher Support Center of Barretos Cancer Hospital, especially the statistician Zanardo C. for assisting in the statistical analysis.This study received financial support from Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (Fapesp, Proc: 10/ 16796-0, Sao Paulo, Brazil)

Uma história de conceitos na saúde pública: integralidade, coordenação, descentralização, regionalização e universalidade A history of public health concepts: integrity, coordination, decentralization, regionalization, and universality

O Sistema Único de Saúde conferiu visibilidade a uma série de conceitos próprios da organização de sistemas de saúde. Entre eles a integralidade, que delimita fronteiras comuns com quase todos os demais princípios do Sistema, tem sido objeto de ampla literatura no Brasil. Com base em extensa revisão de fontes primárias e secundárias, este artigo apresenta uma recuperação histórica dos conceitos de integralidade, descentralização, regionalização e universalidade - ideias e conceitos que em grande parte se conformam e se interligam no ideário da organização dos serviços sanitários pelo modelo dos Centros de Saúde distritais.<br>Brazil's Unified Health System (Sistema Único de Saúde) has highlighted a series of concepts specific to the organization of healthcare systems. Among these, integrity - which shares boundaries with almost all other System principles - has been the object of much academic production in Brazil. Based on an extensive review of primary and secondary sources, the article offers a historical recovery of the concepts of integrity, decentralization, regionalization, and universality - ideas and concepts that in good measure are shaped by and interlinked with the set of ideals of the organization of sanitary services according to the district health centers model