Candida clinical species identification : molecular and biochemical methods

In 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

Variação intra e interpessoal como fatores determinantes para o cálculo do número de observações para estimar a ingestão dietética habitual de adolescentes

This cross-sectional study describes the variation in the dietary intake of energy and macronutrients based on estimated coefficients of within- and between-person variation and intends to calculate the number of days required to evaluate the dietary intake of adolescents in Piracicaba, Brazil. The sample was made up by ninety-two adolescents aged between eleven and sixteen years. Interviews were performed to assess demographic, anthropometric and dietary variables, which were evaluated by the answers obtained through two 24-hour recalls. Descriptive analyses were performed and variances and Coefficients of variation within- and between-person were obtained by results of one-way ANOVA. The mean energy intake observed was 2,326.2 kilocalories; mean macronutrient intake came to 89.0 grams of fatty acids, 305.3 grams of carbohydrates and 82.2 grams of proteins. Coefficients of within-person variation ranged from 36% to 45%, while between-person coefficients varied from 26% to 31%. Variance ratios ranged from 1.35 (carbohydrate) to 2.62 (protein). The lowest number of observations required to correctly evaluate the usual diet calculated (r = 0.90) was six days, for carbohydrates while the highest was eleven, for proteins. Coefficients of variation were similar to those observed in international studies. We conclude that, in this study, two observations were sufficient to obtain reasonable correlations. However, six evaluations are necessary for these adolescents in order to obtain excellent correlations.Este estudo transversal descreve a variabilidade do consumo alimentar de energia e macronutrientes a partir da estimativa dos coeficientes de variação intra e interpessoal e calcula o número de dias necessários para se avaliar a ingestão dietética de adolescentes de Piracicaba, Brasil. A amostra foi constituída por 92 adolescentes com idade entre 11 e 16 anos. Por meio de entrevistas, foram avaliadas variáveis demográficas, antropométricas e de ingestão dietética, levantada por meio de dois Recordatórios de 24h. Foram realizadas análises descritivas, sendo que as variâncias e os coeficientes de variação intra e interpessoal foram obtidos a partir dos resultados da ANOVA com um fator de classificação. O consumo médio de energia observado foi de 2.326,2 Kcal, e em relação aos macronutrientes foram observados valores de 89,0g de lipídios, 305,3g de carboidratos e 82,2g de proteínas. Os coeficientes de variação intrapessoal variaram de 36% a 45% enquanto os coeficientes de variação interpessoal variaram de 26% a 31%. A razão entre as variâncias variou de 1,35 (carboidrato) a 2,62 (proteína). O menor número de observações necessárias para avaliar corretamente (r = 0,90) a dieta habitual foi de 6 dias para carboidratos. O maior número foi para proteínas (11 dias). Os coeficientes de variação foram semelhantes aos observados em estudos internacionais. Conclui-se que, para o presente estudo, duas observações foram suficientes para a obtenção de coeficientes de correlação razoáveis. No entanto, para se obter ótimos coeficientes de correlação, são necessárias no mínimo seis avaliações destes adolescentes.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Avaliação da capacidade de adesão de células de biofilmes de Candida após tratamento com nanopartículas de prata

O objetivo deste estudo foi investigar a capacidade de adesão a células epiteliais humanas e a superfície de poliestireno de leveduras viáveis recuperadas de biofilmes de Candida albicans e Candida glabrata tratados com nanopartículas de prata (NP). Métodos: Biofilmes de Candida (48 hrs) foram formados em placas de microtitulação de 6 poços e tratados por 24 horas com NP (5 nm) nas concentrações de 13,5 e 54 mg/L. Suspensões de células de Candida (107 células viáveis/mL em RPMI 1640) provenientes dos biofilmes tratados com NP foram adicionadas a monocamadas de células HeLa e a poços vazios de placas de microtitulação de 24 poços (para estudar adesão a poliestireno). Após 2 horas de contato, a adesão das leveduras foi determinada usando a coloração com violeta cristal. Resultados: A capacidade de adesão de leveduras viáveis a células HeLa e a superfícies de poliestireno foi significativamente reduzida, e esta redução foi maior quando os biofilmes foram pré-tratados com NP na concentração de 54 mg/L. Ainda, a quantidade de leveduras aderidas das duas cepas diferiu de acordo com o substrato (células epiteliais e superfície de poliestireno). Conclusão: NP podem induzir modificações em leveduras viáveis, as quais podem diminuir a disseminação de infecções por Candida, principalmente em pacientes imunocomprometidos

Contribution of plant-derived phenolic compounds to combat Candida species biofilms

Opportunistic fungal infections, namely involving Candida species, constitute a hot topic for scientific researchers. The present work aims to access antifungal potential of plant-derived phenolic extracts against planktonic cells and biofilms of Candida species. Eucalyptus globulus Labill. (blue gum), Glycyrrhiza glabra L. (licorice), Juglans regia L. (walnut) and Salvia officinalis L. (sage) evidenced to be the most effective Candida growth inhibitors, using disc diffusion assay. Minimal inhibitory (MIC) and minimal fungicidal (MFC) concentrations, and chemical composition of extracts by using HPLC-DAD-ESI/MS were also determined. Blue gum and walnut mainly exerted fungistatic potential, while sage exerted an interesting anti-Candida potential. However, the most prominent candidacidal potential was observed to licorice extract, being achieved the lowest MIC and MFC values. The candidacidal potential of these phenolic extracts was mainly attributed to their high abundance in flavonoids, mainly flavones: luteolin (sage) and apigenin derivatives (licorice), and flavanones: liquiritin derivatives (licorice). In order to deepen the knowledge on the most effective extract, its ability to inhibit biofilm formation was evaluated. Overall, a double concentration of MFC value was necessary to achieve similar results in biofilms. Flow cytometry assays were also carried out, and the obtained results revealed that primary lesion of cellular membrane appear to be most relevant mode of action. Thus, plant derived phenolic compounds evidence a promising potential to combat Candida species biofilms, both individually or combined with conventional therapy

A semiautomated microfluidic platform for real-time investigation of nanoparticles' cellular uptake and cancer cells' tracking

Aims: develop a platform composed of labeled dendrimer nanoparticles and a microfluidic device for real-time monitoring of cancer cells fate. Materials and Methods: The physicochemical and biological characterization of the developed Carboxymethyl-chitosan/poly(amidoamine) (CMCht/PAMAM) dendrimer nanoparticles were performed using TEM, AFM, Zeta Sizer, DSC and cytotoxicity screening. Cancer cell lines derived from different tumor types, including HeLa (Cervical Carcinoma), HCT-116 (Colon Carcinoma) and U87MG (Glioblastoma), were exposed to different concentrations of CMCht/PAMAM dendrimer nanoparticles over a period of 3 days (MTS/DNA). Results: Nanoparticles were successfully modified with an average size of 50 nm. Internalization levels go from 87% to 100% in static and from 95% to 100% in dynamic conditions. Viability levels range from 95% to 100% in static and from 90% to 100% in dynamic conditions, being HCT the most sensitive to the presence of the NP. Conclusions: the results show different responses to the presence of 0.5 mg.mL-1 dendrimer nanoparticles when comparing static to dynamic conditions, with a tendency towards higher sensitivity when subjected to confinement. This work demonstrated that the proposed microfluidic-based platform allows real-time cell monitoring, which, upon more studies, namely the assessment of the drug release effect, could be used for cancer theranostics.FR Maia acknowledges ERC-2012-ADG 20120216–321266 (ComplexiTE) for her Postdoc scholarship. JM Oliveira thanks Portuguese Foundation for Science and Technology (FCT) for his distinction attributed under the FCT Investigator program (IF/00423/2012). BM Costa also thanks Portuguese Foundation for Science and Technology (PTDC/SAU-GMG/113795/2009 and IF/00601/2012 to BM Costa), Fundação Calouste Gulbenkian (BM Costa) and Liga Portuguesa Contra o Cancro (BM Costa). MR Carvalho also thanks the funding through the LA ICVS/3Bs project (UID/Multi/50026/2013). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.info:eu-repo/semantics/publishedVersio

Identification of protein-coding and non-coding RNA expression profiles in CD34+ and in stromal cells in refractory anemia with ringed sideroblasts

<p>Abstract</p> <p>Background</p> <p>Myelodysplastic syndromes (MDS) are a group of clonal hematological disorders characterized by ineffective hematopoiesis with morphological evidence of marrow cell dysplasia resulting in peripheral blood cytopenia. Microarray technology has permitted a refined high-throughput mapping of the transcriptional activity in the human genome. Non-coding RNAs (ncRNAs) transcribed from intronic regions of genes are involved in a number of processes related to post-transcriptional control of gene expression, and in the regulation of exon-skipping and intron retention. Characterization of ncRNAs in progenitor cells and stromal cells of MDS patients could be strategic for understanding gene expression regulation in this disease.</p> <p>Methods</p> <p>In this study, gene expression profiles of CD34⁺cells of 4 patients with MDS of refractory anemia with ringed sideroblasts (RARS) subgroup and stromal cells of 3 patients with MDS-RARS were compared with healthy individuals using 44 k combined intron-exon oligoarrays, which included probes for exons of protein-coding genes, and for non-coding RNAs transcribed from intronic regions in either the sense or antisense strands. Real-time RT-PCR was performed to confirm the expression levels of selected transcripts.</p> <p>Results</p> <p>In CD34⁺cells of MDS-RARS patients, 216 genes were significantly differentially expressed (q-value ≤ 0.01) in comparison to healthy individuals, of which 65 (30%) were non-coding transcripts. In stromal cells of MDS-RARS, 12 genes were significantly differentially expressed (q-value ≤ 0.05) in comparison to healthy individuals, of which 3 (25%) were non-coding transcripts.</p> <p>Conclusions</p> <p>These results demonstrated, for the first time, the differential ncRNA expression profile between MDS-RARS and healthy individuals, in CD34⁺cells and stromal cells, suggesting that ncRNAs may play an important role during the development of myelodysplastic syndromes.</p

Análise do padrão de uso de recursos florais por duas espécies de Melipona Illiger, 1806 (Hymenoptera: Apidae) nas dunas interiores do médio Rio São Francisco, Bahia, Brasil

The populations of Melipona (Eomelipona) asilvai Moure, 1971 and Melipona (Melipona) mandacaia Smith, 1863 resident in continental sand dunes from the medium São Francisco River were studied in order to verify if these bee species show low similarity in floral resource use. The bees were captured on the flowers, using entomological nets, from 6:00 a.m. to 5:00 p.m., in a restricted area (10 ha) covered with “caatinga” vegetation from February to December 2000. The flowering plants were collected and identified, and the number of flowers was estimated. 131 individuals of the species M. asilvai (53.4%) and M. mandacaia (46.6%) were sampled visiting flowers of 14 plant species (7 families). The most visited plant species were Byrsonima gardnerana Adr.Juss. (Malpighiaceae) (45.8%), Copaifera coriacea Mart. (Leguminosae: Caesalpinioideae) (12.2%), and Serjania comata Radlk. (Sapindaceae) (11.4%). Melipona bees concentrated their activities on “mass flowering” plant species and were observed foraging mainly from 06:00h to 08:00h a.m. No relation was observed between the number of bees sampled and the total of flowers estimated. This suggests that the quantity of trophic resources was not limiting. The low similarity value in the use of trophic resources between the melipona species suggests that they partition resources in the study area.As populações de Melipona (Eomelipona) asilvai Moure, 1971 e Melipona (Melipona) mandacaia Smith, 1863, residentes nas dunas interiores do médio Rio São Francisco, foram estudadas com o objetivo de verificar se essas abelhas apresentam baixa similaridade no uso de recursos tróficos. As abelhas foram coletadas nas flores utilizando-se redes entomológicas, das 6:00h às 17:00h, em uma área restrita (10 ha) com vegetação de caatinga, no período de fevereiro a dezembro de 2000. As plantas floridas foram coletadas, identificadas e o número de flores foi estimado. Amostrou-se um total de 131 indivíduos, sendo 53,4% de M. asilvai e 46,6% de M. mandacaia, visitando as flores de 14 espécies vegetais (7 famílias). As espécies vegetais predominantemente visitadas foram Byrsonima gardnerana Adr.Juss. (Malpighiaceae) (45,8%), Copaifera coriacea Mart. (Leguminosae: Caesalpinioideae) (12,2%) e Serjania comata Radlk. (Sapindaceae) (11,4%). As melíponas concentraram suas atividades em poucas espécies vegetais com floração massal e apresentaram maior atividade diária das 6:00h às 8:00h. Não houve relação entre o número de indivíduos coletados e o número de flores estimadas, sugerindo que a quantidade de recursos não foi limitante. O baixo valor de similaridade no uso de recursos tróficos sugere que essas espécies partilham recursos tróficos na área