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71.
Carroll DS Emerson GL Li Y Sammons S Olson V Frace M Nakazawa Y Czerny CP Tryland M Kolodziejek J Nowotny N Olsen-Rasmussen M Khristova M Govil D Karem K Damon IK Meyer H 《PloS one》2011,6(8):e23086
Cowpox virus (CPXV) is described as the source of the first vaccine used to prevent the onset and spread of an infectious disease. It is one of the earliest described members of the genus Orthopoxvirus, which includes the viruses that cause smallpox and monkeypox in humans. Both the historic and current literature describe "cowpox" as a disease with a single etiologic agent. Genotypic data presented herein indicate that CPXV is not a single species, but a composite of several (up to 5) species that can infect cows, humans, and other animals. The practice of naming agents after the host in which the resultant disease manifests obfuscates the true taxonomic relationships of "cowpox" isolates. These data support the elevation of as many as four new species within the traditional "cowpox" group and suggest that both wild and modern vaccine strains of Vaccinia virus are most closely related to CPXV of continental Europe rather than the United Kingdom, the homeland of the vaccine. 相似文献
72.
Roess AA Monroe BP Kinzoni EA Gallagher S Ibata SR Badinga N Molouania TM Mabola FS Mombouli JV Carroll DS MacNeil A Benzekri NA Moses C Damon IK Reynolds MG 《PLoS neglected tropical diseases》2011,5(10):e1356
Background
In areas where health resources are limited, community participation in the recognition and reporting of disease hazards is critical for the identification of outbreaks. This is particularly true for zoonotic diseases such as monkeypox that principally affect people living in remote areas with few health services. Here we report the findings of an evaluation measuring the effectiveness of a film-based community outreach program designed to improve the understanding of monkeypox symptoms, transmission and prevention, by residents of the Republic of the Congo (ROC) who are at risk for disease acquisition.Methodology/Principal Findings
During 90 days, monkeypox outreach was conducted for ∼23,860 people in northern ROC. Two hundred seventy-one attendees (selected via a structured sample) were interviewed before and after participating in a small-group outreach session. The proportion of interviewees demonstrating monkeypox-specific knowledge before and after was compared. Significant gains were measured in areas of disease recognition, transmission, and mitigation of risk. The ability to recognize at least one disease symptom and a willingness to take a family member with monkeypox to the hospital increased from 49 and 45% to 95 and 87%, respectively (p<0.001, both). Willingness to deter behaviors associated with zoonotic risk, such as eating the carcass of a primate found dead in the forest, remained fundamentally unchanged however, suggesting additional messaging may be needed.Conclusions/Significance
These results suggest that our current program of film-based educational activities is effective in improving disease-specific knowledge and may encourage individuals to seek out the advice of health workers when monkeypox is suspected. 相似文献73.
Martínez O Ecochard V Mahéo S Gross G Bodin P Teissié J Escudier JM Paquereau L 《PloS one》2011,6(10):e25510
(S(C5'), R(P)) α,β-D- Constrained Nucleic Acids (CNA) are dinucleotide building blocks that can feature either B-type torsional angle values or non-canonical values, depending on their 5'C and P absolute stereochemistry. These CNA are modified neither on the nucleobase nor on the sugar structure and therefore represent a new class of nucleotide with specific chemical and structural characteristics. They promote marked bending in a single stranded DNA so as to preorganize it into a loop-like structure, and they have been shown to induce rigidity within oligonucleotides. Following their synthesis, studies performed on CNA have only focused on the constraints that this family of nucleotides introduced into DNA. On the assumption that bending in a DNA template may produce a terminator structure, we investigated whether CNA could be used as a new strong terminator of polymerization in PCR. We therefore assessed the efficiency of CNA as a terminator in PCR, using triethylene glycol phosphate units as a control. Analyses were performed by denaturing gel electrophoresis and several PCR products were further analysed by sequencing. The results showed that the incorporation of only one CNA was always skipped by the polymerases tested. On the other hand, two CNA units always stopped proofreading polymerases, such as Pfu DNA polymerase, as expected for a strong replication terminator. Non-proofreading enzymes, e.g. Taq DNA polymerase, did not recognize this modification as a strong terminator although it was predominantly stopped by this structure. In conclusion, this first functional use of CNA units shows that these modified nucleotides can be used as novel polymerization terminators of proofreading polymerases. Furthermore, our results lead us to propose that CNA and their derivatives could be useful tools for investigating the behaviour of different classes of polymerases. 相似文献
74.
Aim Our aim was to elucidate the postglacial migration of Viola rupestris F.W. Schmidt, with its two subspecies, rupestris and relicta Jalas, in Europe, using molecular methods. Location Norway, Sweden, Finland, England, the Netherlands, France and Switzerland. Methods Isoenzymes were analysed from 49 populations of Viola rupestris s.lat. Based on former experience of variation in the taxon, the following were included: aspartate aminotransferase, leucine/aminopeptidase, and phosphoglucomutase, yielding a total of nine interpretable and six variable (putative) loci. Results Six multilocus phenotypes were revealed (A–F). Phenotype A (only one individual) is restricted to northern Norway, B is shared by all populations in northern Norway and an isolated population on the west coast of southern Norway (Møre). Phenotype B comes close to C, co‐occurring with D in England, the latter also occurring in southern France. Phenotypes E and F occur in the rest of Europe. Main conclusions Viola rupestris ssp. relicta Jalas, previously known only from northern Scandinavia (northern unicentric), was discovered on the west coast of southern Norway (Møre), making the taxon ‘bicentric’. Populations are connected through a putative migration route from the Grands Causses in southern France (Massif Central) via England and western Norway to northern Scandinavia. The Grands Causses might represent a glacial refugium. 相似文献
75.
76.
Brandt I De Vriendt K Devreese B Van Beeumen J Van Dongen W Augustyns K De Meester I Scharpé S Lambeir AM 《Peptides》2005,26(12):2536-2546
The function of prolyl oligopeptidase (PO) has been associated with several disorders of the central nervous system. The purpose of this study was to identify endogenous substrates for recombinant porcine PO in porcine brain. The smaller polypeptides were extracted from total brain homogenates and fractionated by two-dimensional chromatography prior to incubation with PO. Shifts in the mass spectrum between the control and the incubated sample, marked potential substrates. Using MSMS peptide sequencing techniques, we identified several fragments of intracellular proteins as potential substrates, which opens new perspectives for finding the function of PO in the intracellular space. 相似文献
77.
Kühn I Iversen A Finn M Greko C Burman LG Blanch AR Vilanova X Manero A Taylor H Caplin J Domínguez L Herrero IA Moreno MA Möllby R 《Applied and environmental microbiology》2005,71(9):5383-5390
Vancomycin-resistant enterococci (VRE) in Europe are thought to have emerged partly due to the use of the glycopeptide avoparcin in animal husbandry. We compared the occurrence of VRE in geographical regions of Europe in which until 1997 large amounts of avoparcin were used (Spain, United Kingdom, and Denmark) with the occurrence of VRE in Sweden, where avoparcin was banned in 1986. We also studied the relatedness between VRE strains from different regions and habitats. In total, 2,580 samples were collected from humans, animals, and the environment (soil, sewage, recipient water). VRE resistant to 20 microg/ml vancomycin were identified in 8.2% of the samples and were found most frequently in raw and treated urban sewage samples (means, 71% and 36% of the samples, respectively), pig manure (17%), and hospital sewage (16%). The proportions of VRE-positive sewage samples were similar in Sweden, Spain, and the United Kingdom, whereas pig feces and manure were more often positive in Spain than in Sweden (30% versus 1%). Most VRE were Enterococcus faecium carrying vanA, and computerized biochemical phenotyping of the isolates of different ecological origins showed a high degree of polyclonality. In conclusion, it seems that animal-associated VRE probably reflect the former use of avoparcin in animal production, whereas VRE in human-associated samples may be a result of antibiotic use in hospitals. Since there seems to be a reservoir of the resistance genes in all countries studied, precautions must be taken to limit the use of antibiotics and antibiotic-like feed additives. 相似文献
78.
Species traits which facilitate introduction and predominance have been quantitatively ranked using interval arithmetic to search for common patterns among 113 marine macroalgae introduced in Europe. Three main categories were used: dispersal, establishment and ecological impact. These were further subdivided into more specific categories, a total of 13. Introduced species were compared with the same number of native species randomized from the same families as the introduced. Invasive species (i.e. species having a negative ecological or economical impact) were also compared with non-invasive introductions, separately for the three algal groups. In many categories, as well as when adding all species, the introduced species ranked more hazardous than the native species and the invasive species ranked higher than the non-invasive ones. The ranking within the three main categories differed, reflecting different strategies between the species within the three algal groups. When all categories (excluding salinity and temperature) were summed, the top five risk species, all invasive, were, in descending order, Codium fragile spp.tomentosoides, Caulerpa taxifolia, Undaria pinnatifida, Asparagopsis armata and Grateloupia doryphora, while Sargassum muticum ranked eight and Caulerpa racemosa ten. Fifteen of the twenty-six species listed as invasive were among the twenty highest ranked. 相似文献
79.
The hepatic predominating cytochrome P450, CYP3A4, plays an essential role in the detoxification of bile acids and is important in pathological conditions such as cholestasis where CYP3A4 is adaptively up-regulated. However, the mechanism that triggers the up-regulation of CYP3A4 is still not clear. In this study, using recombinant CYP3A4 and human liver microsomes, we demonstrate that CYP3A4 can metabolise lithocholic acid into 3-dehydrolithocholic acid, a potent activator of the nuclear receptors, pregnane X receptor and 1,25-dihydroxy vitamin D3 receptor, which are known to regulate the expression of CYP3A4. This process thus provides a feed-forward metabolism of toxic bile acid that may be of importance in maintaining bile acid homeostasis. We also provide evidence for a novel CYP3A4-mediated metabolic pathway of the secondary bile acid deoxycholic acid. Patients treated with the antiepileptic drug carbamazepine, a CYP3A4 inducer, had markedly elevated urinary excretion of 1beta-hydroxydeoxycholic acid compared to healthy controls. The importance of CYP3A4 in this process was verified by incubations with recombinant CYP3A4 and human liver microsomes, both of which efficiently converted deoxycholic acid into 1beta-hydroxydeoxycholic acid. Interestingly, CYP3A4 was also found to be active against the secondary bile acid ursodeoxycholic acid. 相似文献
80.
Mutation of the binding site for Cbl (Tyr1045) in the EGF receptor (EGFR) results in impaired ubiquitination but does not affect EGFR internalization. However, the Y1045F mutation resulted in strongly decreased degradation of the EGFR, as well as efficient recycling of EGFR to the plasma membrane. Significantly, more wild-type EGFR than Y1045F EGFR was found localizing to multivesicular late endosomes. Ubiquitination of the EGFR was in HeLa cells inhibited both upon overexpressing the N-terminal part of Cbl and upon overexpressing a double mutant Grb2 incapable of interacting with Cbl and thereby being incapable of indirectly recruiting Cbl to the EGFR. Collectively, these data suggest that the ubiquitination resulting from direct binding of Cbl to pTyr1045 of the EGFR is critical for lysosomal sorting of the EGFR in contrast to ubiquitination resulting from Grb2-mediated binding of Cbl to the EGFR. 相似文献