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41.
The application of a biological electroacoustic sensor based on a lateral electric-field-excited piezoelectric resonator for the study of bacterial cells that interact with specific bacteriophages, mini-antibodies, and polyclonal antibodies was successfully demonstrated. The determined lower limit of microbialcell detection was approximately of 103 to 104 cells/mL for the duration of the assay of 10 min. The possibility of bacterial-cell detection via interaction with specific agents in the presence of extraneous microbiota was shown. The method allowed us to determine the spectrum of lytic activity of bacteriophages and the sensitivity of microbial cells to bacteriophages. The results of the study showed that application of a sensor piezoelectric lateral-field resonator is a promising technique for the detection and identification of microbial cells and determination of their phage resistance in microbiology, medicine, and veterinary medicine. Furthermore, the results of the experiments made it possible to understand the mechanisms of the processes that occur in a suspension of bacterial cells in the presence of various biological agents. The method also may provide useful information regarding biophysical mechanisms of interactions that occur in microbial populations. 相似文献
42.
Gro O. Nygaard Elisabeth G. Celius Sigrid A. de Rodez Benavent Piotr Sowa Marte W. Gustavsen Anders M. Fjell Nils I. Landr? Kristine B. Walhovd Hanne F. Harbo 《PloS one》2015,10(8)
New treatment options may make “no evidence of disease activity” (NEDA: no relapses or disability progression and no new/enlarging MRI lesions, as opposed to “evidence of disease activity” (EDA) with at least one of the former), an achievable goal in relapsing-remitting multiple sclerosis (RRMS). The objective of the present study was to determine whether early RRMS patients with EDA at one-year follow-up had different disability, cognition, treatment and gray matter (GM) atrophy rates from NEDA patients and healthy controls (HC). RRMS patients (mean age 34 years, mean disease duration 2.2 years) were examined at baseline and one-year follow-up with neurological (n = 72), neuropsychological (n = 56) and structural MRI (n = 57) examinations. Matched HC (n = 61) were retested after three years. EDA was found in 46% of RRMS patients at follow-up. EDA patients used more first line and less second line disease modifying treatment than NEDA (p = 0.004). While the patients groups had similar disability levels at baseline, they differed in disability at follow-up (p = 0.010); EDA patients progressed (EDSS: 1.8–2.2, p = 0.010), while NEDA patients improved (EDSS: 2.0–1.7, p<0.001). Cognitive function was stable in both patient groups. Subcortical GM atrophy rates were higher in EDA patients than HC (p<0.001). These results support the relevance of NEDA as outcome in RRMS and indicate that pathological neurodegeneration in RRMS mainly occur in patients with evidence of disease activity. 相似文献
43.
G.O. Orinda D.J. Waltisbuhl K. Rode-Bramanis B.V. Goodger 《International journal for parasitology》1993,23(8):1011-1017
Serological analysis of Babesia bovis-derived glycolipids by ELISA and the indirect fluorescent antibody technique demonstrated the existence of their antigenic and immunogenic activities not only in B. bovis but also in B. bigemina infections. This indicates that serological cross-reactivity of B. bovis and B. bigemina relates to glycolipids. The negative ELISA reaction obtained with Anaplasma marginale antisera suggested the specificity of the reaction to the genus Babesia. Fractionation of these glycolipids by Florisil Sep-Pak column chromatography with subsequent HPTLC immunostaining and Orcinol staining suggested the presence of carbohydrate antigenic determinants in B. bovis glycolipids. 相似文献
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Data on the occurrence, spatial-bathymetric distribution, and size composition of skilfish Erilepis zonifer are given on the basis of the materials collected at the long-line catches on the Emperor Ridge seamounts. This fish is a large representative of fam. Anoplopomatidae (maximal length 188 cm; weight 88.5 kg). From June to July 2009, the species was found on all five sampled underwater mountains (Nintoku, Jingu, Ojin, Koko, Northern Koko). The fish was found within the depth range 370–1040 m. The initial biomass of skilfish at the studied seamounts calculated by the Leslie method is approximately 203.5 tons. The structure of the range and possible ways of the dispersion of this species in the waters of the continental slope of the North-Pacific rim are discussed. 相似文献
49.
The biodegradability potentials of three detergent products with the trade names Omo, Teepol and sodium dodecyl sulfate (SDS)
by the native bacteria of the Lagos lagoon was carried out using the lagoon die-away method. Physicochemical parameters of
the water samples showed that the lagoon in Apapa was more polluted than at theUniversity of Lagos. In 12 days, approximately 30, 60 and 97% of Omo, Teepol and SDS respectively were degraded. SDS with an alkyl sulfate moiety
as surfactant supported the highest growth of the detergent-utilizing organisms, indicating that the components of Omo and
Teepol are more resistant to microbial attack. The detergent-utilizing bacteria identified were mainly Gram-negative and of
the following genera:Vibrio, Klebsiella, Flavobacterium, Pseudomonas, Escherichia, Enterobacter, Proteus, Shigella andCitrobacter. Vibrio was the most frequently encountered organism whileProteus was the rarest. Results of this investigation had shown that detergents made in Nigeria may still contain components that
are recalcitrant to biodegradation. 相似文献
50.
Biosynthesis of the trichothecene 3-acetyldeoxynivalenol. Identification of the oxygenation steps after isotrichodermin 总被引:2,自引:0,他引:2
Upon feeding an excess of the substrate isotrichodermin, five tricyclic metabolites accumulated in Fusarium culmorum cultures. These compounds were also identified as transient intermediates of trichothecene biosynthesis by kinetic pulse labeling. Their structures were characterized by spectroscopic techniques (1H NMR, 13C NMR, 2H NMR, and nuclear Overhauser effect difference experiments) as: 1, 15-deacylcalonectrin; 2, calonectrin; 3, 7-hydroxyisotrichodermin; 4, 8-hydroxyisotrichodermin; and 5, 7, hydroxycalonectrin. Four of these metabolites (1-4) were rigorously proven to be biosynthetic precursors to 3-acetyldeoxynivalenol. Indeed, their deuteriated derivatives were shown to be incorporated very efficiently into 3-acetyldeoxynivalenol by 2H-NMR. In addition, our experimental data suggests that the first oxygenation step after isotrichodermin is at C-15, producing 15-deacylcalonectrin. 相似文献