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31.
Ricardo Ribeiro Silva Carlos Renato Corso Dácio Roberto Matheus 《World journal of microbiology & biotechnology》2010,26(5):841-846
Estimating fungal growth is important in processes of soil bioremediation. It has been demonstrated that ergosterol is a good
indicator of fungal biomass in solid substrata. In the present study were evaluated the effects upon the ergosterol rate of
Lentinus crinitus Berk. and Psilocybe castanella Peck through the culture conditions of these fungi, which are evaluated for the bioremediation of soils contaminated by organochlorates.
A good correlation between fungal biomass and ergosterol was observed for both species. The culture conditions did not influence
the ergosterol rate of L. crinitus. Yet the ergosterol rate of P. castanella was influenced from 35 days of culture and when grown in the presence of 15.00 g hexachlorobenzene l−1 of culture medium. So it is possible to estimate growth of both species using ergosterol as indicator in processes of soil
bioremediation since the influences observed in the ergosterol rate of P. castanella are considered. 相似文献
32.
Machado AS Andrade GM Januário JN Fernandes MD Carneiro AC Carneiro M Carellos EV Romanelli RM Vasconcelos-Santos DV Vitor RW 《Memórias do Instituto Oswaldo Cruz》2010,105(6):757-761
The aim of this study was to evaluate the utility of western blot (WB) analysis as a diagnostic tool for congenital toxoplasmosis in 215 newborn infants. The children were submitted to clinical examinations to assess macular, neurological and hearing signals. The WB results obtained were compared to the persistence of IgG antibodies at the end of 12 months, which is regarded as the "gold standard" diagnosis of congenital toxoplasmosis. Association between the WB results and the clinical signs presented by the infants was also assessed. Of the 215 children, 177 had a confirmed congenital toxoplasmosis diagnosis and 38 were uninfected. IgG-WB showed a sensitivity of 73.5% and a specificity of 97.4%. IgM-WB showed a sensitivity of 54.8% and a specificity of 94.7%. The IgG-WB and IgM-WB combination increased the sensitivity to 86.5%. The IgM-WB-positive children had a 1.4-fold greater risk of presenting active macular lesions than did those that were IgM-WB-negative. This study showed that the WB assay is a useful tool to confirm a diagnosis of congenital toxoplasmosis and that the IgM-WB-positive results can indicate active macular lesions in newborn infants. 相似文献
33.
Bunholi Ingrid Vasconcellos da Silva Ferrette Bruno Lopes Domingues Rodrigo Rodrigues Rotundo Matheus Marcos Cuevas Juan Martín García Mirta Gómez Sebastián de Freitas Renato Hajenius Aché Oliveira Claudio Foresti Fausto Mendonça Fernando Fernandes 《Hydrobiologia》2022,849(9):2177-2192
Hydrobiologia - The angular angelshark (Squatina guggenheim) is a coastal endangered angel shark from the Southwest Atlantic Ocean and one of the major bycatch victims. Despite major concerns about... 相似文献
34.
Miriam YH Ueda Paulo G Alvarenga Juliana M Real Eloisa de Sá Moreira Aripuan? Watanabe Ana Maria Passos-Castilho Matheus Vescovi Yana Novis Vanderson Rocha Adriana Seber Jose SR Oliveira Celso A Rodrigues Celso FH Granato 《Memórias do Instituto Oswaldo Cruz》2015,110(4):461-467
Human herpesvirus 6 (HHV-6) may cause severe complications after haematopoietic stem
cell transplantation (HSCT). Monitoring this virus and providing precise, rapid and
early diagnosis of related clinical diseases, constitute essential measures to
improve outcomes. A prospective survey on the incidence and clinical features of
HHV-6 infections after HSCT has not yet been conducted in Brazilian patients and the
impact of this infection on HSCT outcome remains unclear. A rapid test based on
real-time quantitative polymerase chain reaction (qPCR) has been optimised to screen
and quantify clinical samples for HHV-6. The detection step was based on reaction
with TaqMan® hydrolysis probes. A set of previously described primers and
probes have been tested to evaluate efficiency, sensitivity and reproducibility. The
target efficiency range was 91.4% with linearity ranging from 10-106
copies/reaction and a limit of detection of five copies/reaction or 250 copies/mL of
plasma. The qPCR assay developed in the present study was simple, rapid and
sensitive, allowing the detection of a wide range of HHV-6 loads. In conclusion, this
test may be useful as a practical tool to help elucidate the clinical relevance of
HHV-6 infection and reactivation in different scenarios and to determine the need for
surveillance. 相似文献
35.
Differential effects of temperature change and human impact on European Late Quaternary mammalian extinctions
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Sara Varela Matheus Souza Lima‐Ribeiro JosÉ Alexandre Felizola Diniz‐Filho David Storch 《Global Change Biology》2015,21(4):1475-1481
Species that inhabited Europe during the Late Quaternary were impacted by temperature changes and early humans, resulting in the disappearance of half of the European large mammals. However, quantifying the relative importance that each factor had in the extinction risk of species has been challenging, mostly due to the spatio‐temporal biases of fossil records, which complicate the calibration of realistic and accurate ecological niche modeling. Here, we overcome this problem by using ecotypes, and not real species, to run our models. We created 40 ecotypes with different temperature requirements (mean temperature from ?20 °C to 25 °C and temperature range from 10 °C to 40 °C) and used them to quantify the effect of climate change and human impact. Our results show that cold‐adapted ecotypes would have been highly affected by past temperature changes in Europe, whereas temperate and warm‐adapted ecotypes would have been positively affected by temperature change. Human impact affected all ecotypes negatively, and temperate ecotypes suffered the greatest impacts. Based on these results, the extinction of cold‐adapted species like Mammuthus primigenius may be related to temperature change, while the extinction of temperate species, like Crocuta crocuta, may be related to human impact. Our results suggest that temperature change and human impact affected different ecotypes in distinct ways, and that the interaction of both impacts may have shaped species extinctions in Europe. 相似文献
36.
P. B. Matheus Carnevali M. Rohrssen M. R. Williams A. B. Michaud H. Adams D. Berisford G. D. Love J. C. Priscu O. Rassuchine K. P. Hand A. E. Murray 《Geobiology》2015,13(2):181-197
The permafrost on the North Slope of Alaska is densely populated by shallow lakes that result from thermokarst erosion. These lakes release methane (CH4) derived from a combination of ancient thermogenic pools and contemporary biogenic production. Despite the potential importance of CH4 as a greenhouse gas, the contribution of biogenic CH4 production in arctic thermokarst lakes in Alaska is not currently well understood. To further advance our knowledge of CH4 dynamics in these lakes, we focused our study on (i) the potential for microbial CH4 production in lake sediments, (ii) the role of sediment geochemistry in controlling biogenic CH4 production, and (iii) the temperature dependence of this process. Sediment cores were collected from one site in Siqlukaq Lake and two sites in Sukok Lake in late October to early November. Analyses of pore water geochemistry, sedimentary organic matter and lipid biomarkers, stable carbon isotopes, results from CH4 production experiments, and copy number of a methanogenic pathway‐specific gene (mcrA) indicated the existence of different sources of CH4 in each of the lakes chosen for the study. Analysis of this integrated data set revealed that there is biological CH4 production in Siqlukaq at moderate levels, while the very low levels of CH4 detected in Sukok had a mixed origin, with little to no biological CH4 production. Furthermore, methanogenic archaea exhibited temperature‐dependent use of in situ substrates for methanogenesis, and the amount of CH4 produced was directly related to the amount of labile organic matter in the sediments. This study constitutes an important first step in better understanding the actual contribution of biogenic CH4 from thermokarst lakes on the coastal plain of Alaska to the current CH4 budgets. 相似文献
37.
de Andrade SA Pedrosa MF de Andrade RM Oliva ML van den Berg CW Tambourgi DV 《Biochemical and biophysical research communications》2005,327(1):117-123
Envenomation by arachnids of the genus Loxosceles can induce a variety of biological effects, including dermonecrosis and hemolysis. We have previously identified in L. intermedia venom two highly homologous proteins with sphingomyelinase activity, termed P1 and P2, responsible for all these pathological events, and also an inactive isoform P3. The toxins P1 and P2 displayed 85% identity with each other at the amino acid level and showed a 57% identity with SMase I, an active toxin from L. laeta venom. Circular dichroism was used to determine and compare the solution structure of the active and inactive isoforms. Effects of pH and temperature change on the CD spectra of the toxins were investigated and correlated with the biological activities. This study sheds new light on the structure-function relationship of homologous proteins with distinct biological properties and represents the first report on the structure-function relationship of Loxosceles sphingomyelinases D. 相似文献
38.
Ferreira AR Bonatto F de Bittencourt Pasquali MA Polydoro M Dal-Pizzol F Fernández C de Salles AA Moreira JC 《Bioelectromagnetics》2006,27(6):487-493
Mobile telephones and their base stations are an important source of ultra high frequency electromagnetic fields (UHF-EMFs; 800-1800 MHz) and their utilization is increasing all over the world. Epidemiological studies have suggested that low energy UHF-EMFs may have biological effects, such as changes in oxidative metabolism after exposure. Therefore, we have investigated the effect of acute UHF-EMF exposure on non-enzymatic antioxidant defense and lipid and protein oxidative damage in the rat frontal cortex and hippocampus. We have used malondialdehyde (MDA) and carbonyl assays to assess lipid and protein oxidative damages, respectively. No changes in lipid and protein damage, and also in non-enzymatic defense were found in frontal cortex or hippocampus. These results suggest that acute UHF-EMF exposure is not able to produce detectable oxidative stress in rats from any age tested. However, more tests using a longer period of exposure and evaluating other tissues are necessary to ensure that there is no health risk associated with the use of mobile phones. 相似文献
39.
Murakami MT Fernandes-Pedrosa MF de Andrade SA Gabdoulkhakov A Betzel C Tambourgi DV Arni RK 《Biochemical and biophysical research communications》2006,342(1):323-329
Spider venom sphingomyelinases D catalyze the hydrolysis of sphingomyelin via an Mg(2+) ion-dependent acid-base catalytic mechanism which involves two histidines. In the crystal structure of the sulfate free enzyme determined at 1.85A resolution, the metal ion is tetrahedrally coordinated instead of the trigonal-bipyramidal coordination observed in the sulfate bound form. The observed hyperpolarized state of His47 requires a revision of the previously suggested catalytic mechanism. Molecular modeling indicates that the fundamental structural features important for catalysis are fully conserved in both classes of SMases D and that the Class II SMases D contain an additional intra-chain disulphide bridge (Cys53-Cys201). Structural analysis suggests that the highly homologous enzyme from Loxosceles bonetti is unable to hydrolyze sphingomyelin due to the 95Gly-->Asn and 134Pro-->Glu mutations that modify the local charge and hydrophobicity of the interfacial face. Structural and sequence comparisons confirm the evolutionary relationship between sphingomyelinases D and the glicerophosphodiester phosphoesterases which utilize a similar catalytic mechanism. 相似文献
40.
A new species of Lauraceae, Beilschmiedia vestita, from the Brazilian Atlantic forest, in Minas Gerais state, is described and illustrated. Its morphological similarities
and differences in relation to other species of Beilschmiedia are discussed. Distribution, habitat, phenology, etymology, and the IUCN Red List category are also provided. 相似文献