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61.
Investigation of germination and aging in Moravian III barley grain by nuclear magnetic resonance. 总被引:2,自引:0,他引:2 下载免费PDF全文
High-resolution, solid-state 1H nuclear magnetic resonance (NMR) techniques are used for the first time to study germination in imbibed Moravian III barley grains. Whereas magic-angle spinning 1H NMR spectra reveal the water and lipid components in barley grains, combined rotation and multiple-pulse spectroscopy techniques provide 1H NMR spectra of grains that reveal the protein and carbohydrate as well as the water and lipid components. Spectra of grains are compared with spectra of model compounds to verify assignments. 1H T1 and T2 measurements using magic-angle spinning only and combined rotation and multiple-pulse spectroscopy techniques provide information about molecular mobility within the grains during inhibition. Some grains were subjected to artificial aging conditions. 1H NMR spectral comparisons are made between normal, viable grains and artificially aged grains. 相似文献
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Giselle Fernandes Maciel de Castro Lima Naomi W. Lucchi Luciana Silva-Flannery Alexandre Macedo- de- Oliveira Angelica D Hristov Juliana Inoue Maria de Jesus Costa-Nascimento Venkatachalam Udhayakumar Silvia M Di Santi 《PloS one》2016,11(3)
Background
Efforts have been made to establish sensitive diagnostic tools for malaria screening in blood banks in order to detect malaria asymptomatic carriers. Microscopy, the malaria reference test in Brazil, is time consuming and its sensitivity depends on microscopist experience. Although molecular tools are available, some aspects need to be considered for large-scale screening: accuracy and robustness for detecting low parasitemia, affordability for application to large number of samples and flexibility to perform on individual or pooled samples.Methodology
In this retrospective study, we evaluated four molecular assays for detection of malaria parasites in a set of 56 samples previously evaluated by expert microscopy. In addition, we evaluated the effect of pooling samples on the sensitivity and specificity of the molecular assays. A well-characterized cultured sample with 1 parasite/μL was included in all the tests evaluated. DNA was extracted with QIAamp DNA Blood Mini Kit and eluted in 50 μL to concentrate the DNA. Pools were assembled with 10 samples each. Molecular protocols targeting 18S rRNA, included one qPCR genus specific (Lima-genus), one duplex qPCR genus/Pf (PET-genus, PET-Pf) and one duplex qPCR specie-specific (Rougemont: Roug-Pf/Pv and Roug-Pm/Po). Additionally a nested PCR protocol specie-specific was used (Snou-Pf, Snou-Pv, Snou-Pm and Snou-Po).Results
The limit of detection was 3.5 p/μL and 0.35p/μl for the PET-genus and Lima-genus assays, respectively. Considering the positive (n = 13) and negative (n = 39) unpooled individual samples according to microscopy, the sensitivity of the two genus qPCR assays was 76.9% (Lima-genus) and 72.7% (PET-genus). The Lima-genus and PET-genus showed both sensitivity of 86.7% in the pooled samples. The genus protocols yielded similar results (Kappa value of 1.000) in both individual and pooled samples.Conclusions
Efforts should be made to improve performance of molecular tests to enable the detection of low-density parasitemia if these tests are to be utilized for blood transfusion screening. 相似文献65.
Arturo González Quiroga Aline Costa Rubens Maciel Filho 《Bioprocess and biosystems engineering》2010,33(8):901-910
Design considerations for enzymatic hydrolysis of lignocellulosic biomass in two and three continuous stirred tank reactors (CSTRs) in series with distributed feeding of substrate and enzyme, followed by a series of CSTRs, are discussed. A previously developed, fitted, and validated kinetic model is extended to accommodate distributed feeding and used along with the micromixing limiting situations of macrofluid and microfluid to describe the reaction system. The capabilities of the reaction system proposed are explored for a range of cumulative substrate concentration from 5 to 20% w/w (dry basis). Continuous distributed feeding does not show advantages in terms of cellulose conversion when compared with the operation where an equivalent mass of substrate is added at the first reactor of the series, but the potential to increase substrate concentration beyond the concentrations that can be handled in conventional CSTRs, and therefore, the volumetric productivity of reactors, is evident. 相似文献
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Barbara Reis-Santos Rodrigo Locatelli Bernardo L. Horta Eduardo Faerstein Mauro N. Sanchez Lee W. Riley Ethel Leonor Maciel 《PloS one》2013,8(4)
Background
Several studies have evaluated the relationship between diabetes mellitus (DM) and tuberculosis (TB), but the nature of this relationship is not fully understood. TB incidence may be influenced by immunosuppression from DM, but this association may be confounded by other clinical and socioeconomic factors. We aimed to assess socio-demographic and clinical differences in TB patients with and without DM.Methods
Using the Brazilian national surveillance system (SINAN), we compared 1,797 subjects with TB and DM with 29,275 subjects diagnosed with TB only in 2009. We performed multivariate analysis to identify factors associated with the presence of DM among TB patients.Results
Subjects with TB – DM were older; have initial positive sputum smear test (OR = 1.42, 95% CI 1.26–1.60), and were more likely to die from TB (OR = 1.44, 95% CI 1.03–2.01). They were less likely to have been institutionalized [in prison, shelter, orphanage, psychiatric hospital (OR = 0.74, 95% CI 0.60–0.93)]; developed extra pulmonary TB (OR = 0.62, 95% CI 0.51–0.75) and to return to TB treatment after abandonment (OR = 0.66, 95% CI 0.51–0.86).Conclusions
Prevalence of NCD continues to rise in developing countries, especially with the rise of elderly population, the prevention and treatment of infectious diseases will be urgent. DM and TB represent a critical intersection between communicable and non-communicable diseases in these countries and the effect of DM on TB incidence and outcomes provide numerous opportunities for collaboration and management of these complex diseases in the national public health programs. 相似文献67.
Diagrammatic Scales for Assessing Brown Eye Spot (Cercospora coffeicola) in Red and Yellow Coffee Cherries 下载免费PDF全文
Paulo V. A. Azevedo de Paula Edson A. Pozza Leandro A. Santos Eugênio Chaves Matheus P. Maciel Júlio César A. Paula 《Journal of Phytopathology》2016,164(10):791-800
Brazil is the world's largest coffee producer. Brown eye spot (BES) (Cercospora coffeicola) is a major crop disease that can cause 15–30% production losses and decrease the coffee beverage quality. Although the influence of this disease on beverage quality has been studied, diagrammatic scales for assessment of the disease severity in berries are still unexplored. Thus, this study has developed and validated diagrammatic scales to assess the severity of BES. Two diagrammatic scales were designed to assess the disease in berries, which can be yellow or red depending on the cultivar. The scale of yellow berries had nine grades: grade 0: 0%; 1: 0.1–5.0%; 2: 5.1–10.0%; 3: 10.1–15.0%; 4: 15.1–20.0%; 5: 20.1–30.0%; 6: 30.1–40.0%; 7: 40.1–60.0%; and 8: higher than 60.0%, while the scale of red berries had eight grades: grade 0: 0%; 1: 0.1–2.5%; 2: 2.6–5.0%; 3: 5.1–10.0%; 4: 10.1–20.0%; 5: 20.1–30.0%; 6: 30.1–50.0%; and 7: higher than 50.0% severity. Using scales improved accuracy and precision with R2 = 0.99 and provided good repeatability and reproducibility of assessments of disease severity. Both scales can be used because the different berry colour influenced the accuracy and precision between the scales. 相似文献
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M. A. O. Marinho M. R. C. Sales-Melo M. B. Melo de Oliveira V. E. de O. Maciel 《Plant biosystems》2017,151(2):291-303
The Vernonieae tribe presents strong taxonomic delimitation problems as it is considered one of the most complex groups of the Asteraceae family, comprising approximately 1100 species distributed across 129 genera. In this study, a comparative analysis of the Vernonieae species was performed to understand the events involved in the chromosome evolution of these species and to further deduce their taxonomy. The representatives were cytogenetically characterized via analyses of morphology, karyotype asymmetry and differential staining with fluorochromes CMA and DAPI as well as FISH. According to morphometric data, all species showed symmetrical karyotypes with prevailing metacentric chromosomes, even in species belonging to different genera. Variability in diploid chromosome number was detected (2n = 18 to 2n = 60), and chromosome sizes were observed to be between 1.00 and 4.09 μm. Additionally, variation in the pattern of heterochromatin was observed mainly in relation to CMA+ bands, in which the number varied from 4 to 16 heterochromatic regions. Only one species, Vernonia scorpioides, presented positive DAPI bands, which were located in the terminal position in most of the chromosomes. The differences in the sizes and quantities of heterochromatic bands may be related to small structural rearrangements during karyotype evolution of the Vernonieae tribe. 相似文献
70.
Angélica Domingues Hristov Maria Carmen Arroyo Sanchez José Jarbas Bittencourt Ferreira Giselle Fernandes Maciel de Castro Lima Juliana Inoue Maria de Jesus Costa-Nascimento Arianni Rondelli Sanchez Eduardo Milton Ramos-Sanchez Silvia Maria Di Santi 《Memórias do Instituto Oswaldo Cruz》2014,109(8):1014-1020
Studies on autochthonous malaria in low-transmission areas in Brazil have acquiredepidemiological relevance because they suggest continued transmission in what remainsof the Atlantic Forest. In the southeastern portion of the state of São Paulo,outbreaks in the municipality of Juquitiba have been the focus of studies on theprevalence of Plasmodium, including asymptomatic cases. Data on the occurrence of thedisease or the presence of antiplasmodial antibodies in pregnant women from thisregion have not previously been described. Although Plasmodium falciparum in pregnantwomen has been widely addressed in the literature, the interaction of Plasmodiumvivax and Plasmodium malariae with this cohort has been poorly explored to date. Wemonitored the circulation of Plasmodium in pregnant women in health facilitieslocated in Juquitiba using thick blood film and molecular protocols, as well asimmunological assays, to evaluate humoural immune parameters. Through real-time andnested polymerase chain reaction, P. vivax and P. malariae were detected for thefirst time in pregnant women, with a positivity of 5.6%. Immunoassays revealed thepresence of IgG antibodies: 44% for ELISA-Pv, 38.4% for SD-Bioline-Pv and 18.4% forindirect immunofluorescence assay-Pm. The high prevalence of antibodies showedsignificant exposure of this population to Plasmodium. In regions with similarprofiles, testing for a malaria diagnosis might be indicated in prenatal care. 相似文献