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921.
In Madagascar, Newcastle disease (ND) has become enzootic after the first documented epizootics in 1946, with recurrent annual outbreaks causing mortality up to 40%. Four ND viruses recently isolated in Madagascar were genotypically and pathotypically characterised. By phylogenetic inference based on the F and HN genes, and also full-genome sequence analyses, the NDV Malagasy isolates form a cluster distant enough to constitute a new genotype hereby proposed as genotype XI. This new genotype is presumably deriving from an ancestor close to genotype IV introduced in the island probably more than 50 years ago. Our data show also that all the previously described neutralising epitopes are conserved between Malagasy and vaccine strains. However, the potential implication in vaccination failures of specific amino acid substitutions predominantly found on surface-exposed epitopes of F and HN proteins is discussed.  相似文献   
922.
Standard and repeated fluorescence in situ hybridization and high-resolution cytometry were used to study topographical parameters of chromosome 11 and 22 territories, EWSR1 and FLI1 genes, and other genetic elements of these chromosomes in human lymphocytes and Ewing sarcoma cells. HSA 11 and its elements (BCL1, FLI1, centromere) were found, on average, more peripherally in comparison with HSA 22 and investigated elements (BCR, EWSR1, centromere). After the elimination of fluctuations of chromosome territories in nuclear volume, it was found that genetic elements in most cases adhered to their territories. The investigated genetic elements of HSA 11 were found close to each other relative to the large molecular lengths among them. This finding indicates a higher degree of chromatin condensation of at least a part of HSA 11 compared with HSA 22. In general, there is no correlation between the physical and molecular distance of two loci of the same chromosome territory. The topographical parameters of the EWSR1 and FLI1 genes do not differ substantially for G(0)-lymphocytes, stimulated lymphocytes and Ewing sarcoma cells. The fusion genes pertaining to both derivative chromosomes 11 and 22 in Ewing sarcoma cell nuclei are shifted to the midway position between the native EWSR1 and FLI1 genes. Comparing results obtained for the EWSR1/FLI1 and ABL1/BCR genes in samples of patients suffering from Ewing sarcoma or chronic myelogenous leukaemia, it can be concluded that the mean positions of the fusion genes are determined by the final structure of the chimeric chromosomes and do not depend on the location of the translocation event.  相似文献   
923.
924.
We present here the results of protein extraction from different ocular regions using different detergents. Extraction strategies used to determine optimal protein extraction included: pressure cycling and aqueous-organic phase extraction in combination with electrophoretic fractionation for anterior, posterior, and peripapillary sclera. Detergent extraction of proteins from freshly enucleated porcine eyes (n = 8) showed significant differences for different eye regions. Protein yield ranged from 2.3 to 50.7 mug protein/mg for different ocular tissues, with the lens yielding the most protein. ASB-14 and Triton X-100 provided the best protein yields (n = 10) for anterior and posterior sclera. The spectrophotometric measurements for ASB-14 were not consistent with SDS-PAGE densitometry. A combination of 0.5% Triton X-100, 0.5% Tween-20, and 0.1% Genapol C-100 was found optimal for extraction from sclera. Proteins from different regions of the eye are best extracted with different detergents. The pressure cycling technology provided superior extraction compared to the other methods. Additional aqueous-organic phase partitioning enables superior fractionation when compared to SDS-PAGE alone. Organic phase fractionation is compatible with MS and allowed identification of 34, 71, and 77 proteins respectively from anterior, posterior, and peripapillary sclera. The extraction strategy may affect the final outcome in protein profiling by MS or by other methods.  相似文献   
925.
Analysis of behavioral sequences displayed by different individuals can be used to infer individual decisions under diverse conditions. This study investigates whether behavioral transitions and routines differ according to the group composition of Guiana dolphins (Sotalia guianensis). We used the Z-score binomial test to detect significant behavioral transitions from a first-order transition matrix. The directed tree method was used to identify behavioral routines. Solitary individuals presented fewer transitions than heterogeneous groups. More routines were observed for heterogeneous than for homogeneous groups, and fewer routines for solitary individuals. Homogeneous groups maximized routines ending in traveling and milling, while heterogeneous groups presented higher probabilities of socializing. The analyses indicate that subgroups formed during Guiana dolphin fission–fusion events differed in probability of behavioral sequences, reflecting different feeding, resting, and socializing needs at different moments.  相似文献   
926.
Abstract

This study evaluated the antibacterial properties of carvacrol and terpinen-4-ol against Porphyromonas gingivalis and Fusobacterium nucleatum and its cytotoxic effects on fibroblast cells. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were examined. The minimum biofilm inhibition concentration (MBIC) was evaluated by XTT assay. Biofilm decontamination on titanium surfaces was quantified (CFU ml?1), evaluated by confocal laser scanning microscopy (CLSM) and cytotoxic activity by MTT. The MIC and MBC for carvacrol were 0.007% and 0.002% for P. gingivalis and F. nucleatum, and 0.06% for terpinen-4-ol for both microorganisms. The MBIC for carvacrol was 0.03% and 0.06% for P. gingivalis and F. nucleatum, and for terpinen-4-ol was 0.06% and 0.24%. The results indicated anti-biofilm activity using carvacrol (0.26%, 0.06%) and terpinen-4-ol (0.95%, 0.24%) and showed cytotoxic activity similar to chlorohexidine (CHX). However, terpinen-4-ol (0.24%) showed higher cell viability than other treatments. Carvacrol and terpinen-4-ol showed antibacterial activity in respect of reducing biofilms. Moreover, CHX-like cytotoxicity was observed.  相似文献   
927.
Mouse Msx 1 gene, orthologous of the Drosophila msh, is involved in several developmental processes. BMP family members are major proteins in the regulation of Msx 1 expression. BMP signaling activates Smad 1/5/8 proteins, which associate to Smad 4 before translocating to the nucleus. Analysis of Msx 1 promoter revealed the presence of three elements similar to the consensus established for Mad, the Smad 1 Drosophila counterpart. Notably, such an element was identified in an enhancer important for Msx 1 regulation. Gel shift analysis demonstrated that proteins from 13.5 dpc embryo associate to this enhancer. Remarkably, supershift assays showed that Smad proteins are present in the complex. Purified Smad 1 and 4 also bind to this fragment. We demonstrate that functional binding sites in this enhancer are confined to the Mad motif and flanking region. Our data suggest that this Mad motif may be functional in response to BMP signaling.  相似文献   
928.
This study aimed to evaluate the effect of silicon (Si) and its interaction with fungicide on the management of sorghum anthracnose. The experiments were carried out in Si‐deficient soil in the 2008/2009 and 2009/2010 growing seasons in a randomized, complete block, split‐split plot design with four replications. Calcium silicate (CS) and lime (L), at the rates of 6 and 5 ton/ha, respectively, were randomly assigned to the main plot. Two sorghum lines, BR‐008 (resistant) and BR‐009 (susceptible), were assigned to the split plots. The split‐split plots corresponded to with or without the fungicide Opera® (epoxiconazole + pyraclostrobin). The residual effect of CS and L from the 2008/2009 growing season was evaluated in the 2009/2010 growing season. For the 2008/2009 growing season, the area under anthracnose progress curve (AUAPC) was reduced by 39 and 42% for lines BR‐008 and BR‐009, respectively, with the application of CS. In the presence of the fungicide, the AUAPC was reduced by 35 and 42% for the CS and L treatments, respectively. Calcium silicate with and without fungicide contributed to decreasing the AUAPC by 44 and 37%, respectively. The fungicide spray decreased the AUAPC by 50 and 39% for lines BR‐008 and BR‐009, respectively. Without fungicide, the AUAPC decreased by 88% for line BR‐008 compared with line BR‐009; however, with fungicide, the reduction reached 90%. The Si leaf tissue concentration significantly increased with the CS application (5.9 g/kg) compared with the L application (0.3 g/kg), regardless of the sorghum line. The yield increased by 0.6 ton/ha with the CS compared to the L application. The fungicide increased yield by 0.48 ton/ha compared with the non‐fungicide spray treatment. The residual effect of CS in the soil increased Si leaf tissue concentration and yield as well as reduced the intensity of anthracnose in the 2009/2010 growing season.  相似文献   
929.
Coagulase-negative staphylococci (CNS) represent an important group of etiologic agents of infections associated with plastic biomaterials, e.g. drains. In the present paper 33 strains of CNS were characterized. All of them were isolated from fluid of pleural drains in patients with lung cancer after pulmonary resection under conditions of antimicrobial prophylaxis. The most frequently isolated species were Staphylococcus epidermidis and S. warneri. The majority of CNS strains showed ability to produce slime and possessed hydrophobic properties of cell surface. Strains of CNS resistant to penicillin and oxacillin, but sensitive to amoxicillin/clavulanate were isolated most frequently. Only two methicillin-resistant strains, belonging to S. haemolyticus, were found. The obtained data indicate that CNS strains colonizing pleural drains had potential ability to adhere to smooth surfaces. Most of isolated strains were susceptible to antibiotics and chemotherapeutics routinely used in staphylococcal infections.  相似文献   
930.
The effects of aquatic macrophyte (willows and sawgrass) removal on flow velocity, tufa deposition, POM dynamics, and macroinvertebrate community structure were studied in the tufa barrier habitats of the barrage system of Plitvice Lakes, Croatia. Samples were collected from two hydraulic habitats (fast > 100 cm s−1 and slow < 100 cm s−1) at both a control (no macrophytes removed) and impact (macrophytes removed) site. Samples were collected with a core sampler (four layers in vertical profile of barrier bed) monthly on 6 dates before and 7 dates after the removal of macrophytes. Macrophytes were removed in May 2002 at the impact site. After the macrophyte removal flow velocity decreased significantly at both hydraulic habitats. Retarded flow resulted in: (a) a decrease in macroinvertebrate density and diversity since most of the taxa were rheophilic (preferring habitats with higher flow velocity) and (b) an increase in POM concentrations (FPOM and UPOM) since decreases in flow velocity facilitate particle deposition in lotic habitats. The effects of macrophyte removal were present, and diminish along the vertical sediment profile of the barrier bed. Tufa deposition was not influenced by the macrophyte removal. Electronic supplementary material Electronic supplementary material is available for this article at and accessible for authorised users.  相似文献   
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