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111.
Erika Souza Vieira Tâmara Karoline de Oliveira Fontes Matheus Mendonça Pereira Hofsky Vieira Alexandre Daniel Pereira da Silva Cleide Mara Faria Soares Álvaro Silva Lima 《Bioprocess and biosystems engineering》2015,38(4):721-728
A novel strategy for the production of lipase by Bacillus sp. ITP-001 in a stirred tank fermenter using perfluorodecalin (PFD) was studied. Firstly, a response surface methodology 22 with three central points was employed to optimise the effect of agitation speed and aeration rate in lipase production. According to the response from the experimental designs, 300 rpm (revolutions per minute) and 0.5 vvm (air volume/liquid volume per minute) were found to provide the best condition (lipolytic activity: LA = 3,140.76 U mL?1). Then, the influence of PFD concentration on the fermentation process was evaluated. Incorporation of PFD at all concentrations above 1 % had no statistically significant influence on lipase production, that is, the previous optimisation allowed the reduction of the amount of PFD added besides increasing lipase production. Furthermore, PFD could be used in three sequential fermentations without altering the statistical production of lipase, reducing by 67 % the cost of PFD addition. 相似文献
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Rosângela M. R. Barbosa Andre Furtado Lêda Regis Walter S. Leal 《Journal of vector ecology》2010,35(1):204-207
A synthetic mixture of an oviposition‐stimulating kairomone for the yellow fever mosquito, Aedes aegypti, comprising of 83% tetradecanoic acid, 16% nonanoic acid and 1% tetradecanoic acid methyl ester (NTT, in short) was tested in a dengue endemic area in Recife, Brazil. Gravid female mosquitoes confined to a cage under semi‐field conditions deposited significantly higher numbers of eggs in traps baited with NTT at doses ranging from 0.6 to 600 ng/μl than in control (water) traps. When tested in homes, egg‐laying in traps baited with 60 ng NTT/μl (final concentration in trap, ≈3.33 ng/ml) and in control traps was not significantly different, but egg deposited in traps with lower dosage (6 ng NTT/μl; final concentration in trap, ≈0.33 ng/ml) was significantly higher than in control traps. In subsequent trials, the numbers of eggs laid in traps baited with 0.6 ng NTT/μl (final concentration in trap, ≈0.033 ng/ml) were not significantly different from the numbers deposited in trap loaded with 6 ng NTT/μl. Egg‐laying was significantly higher in these treatments than in control traps. 相似文献
114.
Brito de Souza VN Nogueira ME Belone Ade F Soares CT 《FEMS immunology and medical microbiology》2010,60(3):270-274
Apoptosis eliminates pathogen-infected cells. Its modulation can influence the course of infections, permitting the survival of intracellular pathogens. In leprosy, which presents several clinical manifestations related to bacillary burden and host immune status, the mechanisms responsible for the persistence of the bacillus are unknown. Few studies have focused on apoptosis over the disease spectrum and as a defense mechanism against Mycobacterium leprae. We evaluated apoptosis using terminal transferase dUTP nick end labeling and the expression of Bcl-2 by immunohistochemistry in skin lesions from 11 tuberculoid and 15 lepromatous leprosy patients. Each specimen was evaluated by determining the number of positive cells in 10 fields at × 400 magnification. We observed a higher number of apoptotic cells in tuberculoid lesions in comparison with lepromatous leprosy (42.5 cells per 10 fields vs. 11.5 cells per 10 fields, P<0.0001). Expression of Bcl-2, conversely, was larger in lepromatous than in tuberculoid samples (172.0 cells per 10 fields vs. 17.7 cells per 10 fields, P<0.0001). These observations suggest modulation of apoptosis in leprosy, primarily in lepromatous patients, for which the decrease in cell death could support M. leprae survival and contribute to the success of infection. Conversely, in tuberculoid patients, apoptosis could contribute to reducing propagation of the bacillus. 相似文献
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Manel Ziadi Feriel Rezouga Hassib Bouallagui Leila Baâti Nada Ben Othman Philippe Thonart Moktar Hamdi 《World journal of microbiology & biotechnology》2010,26(12):2223-2230
The effect of controlled whey hydrolysis by papain on growth of two lactic acid bacteria isolated from artisanal Leben: Lactococcus lactis var. diacetylactis (SLT6 and SLT10) was investigated. The higher biomass and maximum specific growth rate (μ max) were obtained after 30 min of hydrolysis. HPLC analysis of peptides showed that whey hydrolysis reduced the amount of peptides of MW > 400 Da and increased those peptides of MW < 400 Da. The two studied strains exhibited different peptide requirements. The pH-controlled batch cultures in 30 min hydrolysed whey followed the Monod kinetic for growth and for lactate production. The values of the key kinetic constants were: maximum specific growth rate (μ max), 1.08 and 0.56 h?1; yield biomass on lactose (Y x/s), 0.20 and 0.18 g g?1 and saturation constant K s, 4.2 and 2.8 g L?1 for SLT6 and SLT10, respectively. When compared with batch experimental data, the model provided good predictions for growth, lactose utilisation and lactate production profiles. 相似文献
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118.
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
119.
Célia Ferreira Sónia Silva Fábio Faria-Oliveira Eva Pinho Mariana Henriques Cândida Lucas 《BMC microbiology》2010,10(1):238
Background
GUP1 gene was primarily identified in Saccharomyces cerevisiae being connected with glycerol uptake defects in association with osmotic stress response. Soon after, Gup1p was implicated in a complex and extensive series of phenotypes involving major cellular processes. These include membrane and wall maintenance, lipid composition, bud-site selection, cytoskeleton orientation, vacuole morphology, secretory/endocytic pathway, GPI anchors remodelling, and lipid-ordered domains assembly, which is compatible with their inclusion in the Membrane Bound O-acyl transferases (MBOAT) family. In mammals, it has been described as a negative regulator of the Sonic hedgehog pathway involved in morphogenesis, differentiation, proliferation, among other processes. 相似文献120.