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51.
André Mario Doi Antonio Carlos Campos Pignatari Michael B. Edmond Alexandre Rodrigues Marra Luis Fernando Aranha Camargo Ricardo Andreotti Siqueira Vivian Pereira da Mota Arnaldo Lopes Colombo 《PloS one》2016,11(1)
Candidemia is a growing problem in hospitals all over the world. Despite advances in the medical support of critically ill patients, candidiasis leads to prolonged hospitalization, and has a crude mortality rate around 50%. We conducted a multicenter surveillance study in 16 hospitals distributed across five regions of Brazil to assess the incidence, species distribution, antifungal susceptibility, and risk factors for bloodstream infections due to Candida species. From June 2007 to March 2010, we studied a total of 2,563 nosocomial bloodstream infection (nBSI) episodes. Candida spp. was the 7th most prevalent agent. Most of the patients were male, with a median age of 56 years. A total of 64 patients (46.7%) were in the ICU when candidemia occurred. Malignancies were the most common underlying condition (32%). The crude mortality rate of candidemia during the hospital admission was 72.2%. Non-albicans species of Candida accounted for 65.7% of the 137 yeast isolates. C. albicans (34.3%), Candida parapsilosis (24.1%), Candida tropicalis (15.3%) and Candida glabrata (10.2%) were the most prevalent species. Only 47 out of 137 Candida isolates were sent to the reference laboratory for antifungal susceptibility testing. All C. albicans, C. tropicalis and C. parapsilosis isolates were susceptible to the 5 antifungal drugs tested. Among 11 C. glabrata isolates, 36% were resistant to fluconazole, and 64% SDD. All of them were susceptible to anidulafungin and amphotericin B. We observed that C. glabrata is emerging as a major player among non-albicans Candida spp. and fluconazole resistance was primarily confined to C. glabrata and C. krusei strains. Candida resistance to echinocandins and amphotericin B remains rare in Brazil.Mortality rates remain increasingly higher than that observed in the Northern Hemisphere countries, emphasizing the need for improving local practices of clinical management of candidemia, including early diagnosis, source control and precise antifungal therapy. 相似文献
52.
Hauke Thomsen Miguel Inacio da Silva Filho Michael Fuchs Sabine Ponader Elke Pogge von Strandmann Lewin Eisele Stefan Herms Per Hoffmann Andreas Engert Kari Hemminki Asta F?rsti 《PloS one》2016,11(4)
Genome-wide association studies (GWASs) have identified several, mainly co-dominantly acting, single-nucleotide polymorphisms (SNPs) associated with Hodgkin lymphoma (HL). We searched for recessively acting disease loci by performing an analysis of runs of homozygosity (ROH) based on windows of homozygous SNP-blocks and by calculating genomic inbreeding coefficients on a SNP-wise basis. We used data from a previous GWAS with 906 cases and 1217 controls from a population with a long history of no matings between relatives. Ten recurrent ROHs were identified among 25 055 ROHs across all individuals but their association with HL was not genome-wide significant. All recurrent ROHs showed significant evidence for natural selection. As a novel finding genomic inbreeding among cases was significantly higher than among controls (P = 2.11*10−14) even after correcting for covariates. Higher inbreeding among the cases was mainly based on a group of individuals with a higher average length of ROHs per person. This result suggests a correlation of higher levels of inbreeding with higher cancer incidence and might reflect the existence of recessive alleles causing HL. Genomic inbreeding may result in a higher expression of deleterious recessive genes within a population. 相似文献
53.
André Escobar Rozana Wendler da Rocha Bruno Henri Pypendop Darcio Zangirolami Filho Samuel Santos Sousa Carlos Augusto Araújo Valad?o 《PloS one》2016,11(3)
The aim of this study was to measure the temporal effects of intramuscular methadone administration on the minimum anesthetic concentration (MAC) of isoflurane in hens, and to evaluate the effects of the isoflurane-methadone combination on heart rate and rhythm, blood pressure and ventilation. Thirteen healthy adult hens weighing 1.7 ± 0.2 kg were used. The MAC of isoflurane was determined in each individual using the bracketing method. Subsequently, the reduction in isoflurane MAC produced by methadone (3 or 6 mg kg-1, IM) was determined by the up-and-down method. Stimulation was applied at 15 and 30 minutes, and at 45 minutes if the bird had not moved at 30 minutes. Isoflurane MAC reduction was calculated at each time point using logistic regression. After a washout period, birds were anesthetized with isoflurane and methadone, 6 mg kg-1 IM was administered. Heart rate and rhythm, respiratory rate, blood gas values and invasive blood pressure were measured at 1.0 and 0.7 isoflurane MAC, and during 45 minutes after administration of methadone once birds were anesthetized with 0.7 isoflurane MAC. Fifteen minutes after administration of 3 mg kg-1 of methadone, isoflurane MAC was reduced by 2 (-9 to 13)% [logistic regression estimate (95% Wald confidence interval)]. Administration of 6 mg kg-1 of methadone decreased isoflurane MAC by 29 (11 to 46)%, 27 (-3 to 56)% and 10 (-8 to 28)% after 15, 30 and 45 minutes, respectively. Methadone (6 mg kg-1) induced atrioventricular block in three animals and ventricular premature contractions in two. Methadone caused an increase in arterial blood pressure and arterial partial pressure of carbon dioxide, while heart rate and pH decreased. Methadone, 6 mg kg-1 IM significantly reduced isoflurane MAC by 30% in hens 15 minutes after administration. At this dose, methadone caused mild respiratory acidosis and increase in systemic blood pressure. 相似文献
54.
55.
Marcos Vinicius Meiado Mariana Rojas‐Aréchiga José Alves de Siqueira‐Filho Inara Roberta Leal 《Plant Species Biology》2016,31(2):87-97
Environmental factors are used by plants as spatio‐temporal indicators of favorable conditions for seed germination. Thus, the objective of this study was to determine the effect of light and temperature on seed germination of 30 taxa of Cactaceae occurring in northeastern Brazil and to evaluate whether fluctuations in temperature are capable of altering light sensitivity. The seeds were tested for germination under two light conditions (12 h photoperiod and continuous darkness) and 10 temperature treatments: eight constant temperatures (10, 15, 20, 25, 30, 35, 40 and 45°C) and two alternating temperatures (30/20°C and 35/25°C). The species studied showed two photoblastic responses. All cacti from the Cactoideae subfamily (22 taxa) were classified as positive photoblastic (i.e., no germination in darkness), regardless of the temperature treatment used. Likewise, temperature fluctuation did not alter the seed sensitivity to light. On the other hand, the species of the Opuntioideae (five taxa) and Pereskioideae (three taxa) subfamilies are indifferent to light (i.e., germinated both in the presence and absence of light). The cacti from the areas of Caatinga and Cerrado showed an optimal germination temperature of 30°C, while the species from Atlantic Forest and Restinga areas showed an optimal germination temperature of 25°C. 相似文献
56.
Rafael Silva Menezes Aline Terra Soares Jair Gonzalez Marques Júnior Rafael Garcia Lopes Rafael Fonseca da Arantes Roberto Bianchini Derner Nelson Roberto Antoniosi Filho 《Journal of applied phycology》2016,28(5):2679-2686
The purposes of this study were to assess the influence of culture medium on biomass production, fatty acid, and pigment composition of Choricystis minor var. minor and to evaluate the use of this microalga as a source of fatty raw material for biodiesel production. Cultures of C. minor var. minor were grown using WC (Wright’s cryptophyte) and BBM (Bold’s Basal medium) media. BBM medium produced more biomass (984.3 mg L?1) compared to the WC medium (525.7 mg L?1). Despite this result, WC medium produced a higher methyl ester yield for biodiesel production than the BBM medium (170.0 and 90.2 mg g?1 of biomass, respectively). The average percentage of fatty acids obtained using the WC medium (17.0 %) was similar to soybean (18.0 %) and with similar biomass fatty acid profile. However, for pigment production, carotenoids and chlorophyll concentrations were twice as high when using the BBM medium. 相似文献
57.
Esequiel Santos Fábio Ribeiro Pires Fernando Barboza Egreja Filho João Carlos Madalão Robson Bonomo 《International journal of phytoremediation》2019,21(7):652-662
AbstractThis study evaluated remediation of the herbicide sulfentrazone in soils with three different mineralogies (kaolinite, hematite, and gibbsite) and three remediation sulfentrazone treatments (Canavalia ensiformis L., Crotalaria juncea L., and natural attenuation). This study was conducted in a factorial scheme, in triplicate with randomized block design. Sulfentrazone was applied at 0 and 400?g ha?1. We analyzed sulfentrazone residue in the soils by high-performance liquid chromatography and confirmed the results with bioassays of Pennisetum glaucum. Herbicide movement was greater in the kaolinitic soil without plant species. The retention of herbicide in the kaolinitic soil occurred in larger quantities in the 0–12?cm layer, with higher levels found in the treatments with plants. In the hematitic soil with C. juncea, all applied herbicides were concentrated in the 0–12?cm layer. In the other hematitic soil treatments, sulfentrazone was not detected by chemical analysis at any soil depth, although in many treatments, it was detected in the bioassay. Phytoremediation was more efficient with C. ensiformis grown in gibbsitic soil, reducing the sulfentrazone load by approximately 27%. Natural attenuation was more efficient than phytoremediation in oxidic soils due to soil pH and texture soils favored microbial degradation of the compound.
- Highlights
The influence of soil mineralogy of herbicide sulfentrazone retention was evaluated.
Canavalia ensiformis and Crotalaria juncea were evaluated as phytoremediation plants.
Kaolinite soils presented great movement of sulfentrazone in the soil.
Natural attenuation is more efficient in oxide soils than phytoremediation.
58.
59.
Symplocos saxatilis (Symplocaceae), a new dioecious species from Serra do Cipó, Minas Gerais, Brazil
João Luiz M. Aranha Filho Peter W. Fritsch Frank Almeda Angela B. Martins 《Brittonia》2007,59(3):233-237
Symplocos saxatilis from Serra do Cipó, Minas Gerais State, Brazil, is newly described and illustrated on the basis of field and herbarium studies.
It appears to be restricted to “campo rupestre” (rocky field) habitats. This new species is characterized by its 1- to 3-flowered
pedunculate inflorescence, 11 to 14 staminodes of the pistillate flowers, and 0.7–1.5 mm thick endocarp. 相似文献
60.
Torres MR Sousa AP Silva Filho EA Melo DF Feitosa JP de Paula RC Lima MG 《Carbohydrate research》2007,342(14):2067-2074
Alginate fractions from Sargassum vulgare brown seaweed were characterized by (1)H NMR and fluorescence spectroscopy and by rheological measurements. The alginate extraction conditions were investigated. In order to carry out the structural and physicochemical characterization, samples extracted for 1 and 5h at 60 degrees C were further purified by re-precipitation with ethanol and denoted as SVLV (S. vulgare low viscosity) and SVHV (S. vulgare high viscosity), respectively. The M/G ratio values for SVLV and SVHV were 1.56 and 1.27, respectively, higher than the ratio for most Sargassum spp. alginates (0.19-0.82). The homopolymeric blocks F(GG) and F(MM) of these fractions characterized by (1)H NMR spectroscopy were 0.43 and 0.55 for SVHV and 0.36 and 0.58 for SVLV samples, respectively, these values typically being within 0.28-0.77 and 0.07-0.41, respectively. Therefore, the alginate samples from S. vulgare are much richer in mannuronic block structures than those from other Sargassum species. Values of M(w) for alginate samples were also calculated using intrinsic viscosity data. The M(w) value for SVLV (1.94 x 10(5)g/mol) was lower than that for SVHV (3.3 x 10(5)g/mol). Newtonian behavior was observed for a solution concentration as high as 0.7% for SVLV, while for SVHV the solutions behaved as a Newtonian fluid up to 0.5%. The optimal conditions for obtaining the alginates from S. vulgare were 60 degrees C and 5h extraction. Under these conditions, a more viscous alginate in higher yield was extracted from the seaweed biomass. 相似文献