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51.
Knowledge about large-scale and long-term dynamics of (natural) populations is required to assess the efficiency of control
strategies, the potential for long-term persistence, and the adaptability to global changes such as habitat fragmentation
and global warming. For most natural populations, such as pest populations, large-scale and long-term surveys cannot be carried
out at a high resolution. For instance, for population dynamics characterized by irregular abundance explosions, i.e., outbreaks,
it is common to report detected outbreaks rather than measuring the population density at every location and time event. Here,
we propose a mechanical-statistical model for analyzing such outbreak occurrence data and making inference about population
dynamics. This spatio-temporal model contains the main mechanisms of the dynamics and describes the observation process. This
construction enables us to account for the discrepancy between the phenomenon scale and the sampling scale. We propose the
Bayesian method to estimate model parameters, pest densities and hidden factors, i.e., variables involved in the dynamics
but not observed. The model was specified and used to learn about the dynamics of the European pine sawfly (Neodiprion sertifer Geoffr., an insect causing major defoliation of pines in northern Europe) based on Finnish sawfly data covering the years
1961–1990. In this application, a dynamical Beverton–Holt model including a hidden regime variable was incorporated into the
model to deal with large variations in the population densities. Our results gave support to the idea that pine sawfly dynamics
should be studied as metapopulations with alternative equilibria. The results confirmed the importance of extreme minimum
winter temperatures for the occurrence of European pine sawfly outbreaks. The strong positive connection between the ratio
of lake area over total area and outbreaks was quantified for the first time. 相似文献
52.
Seppo AM Saari Kirsi H Juuti Joanna H Palojärvi Kirsi M Väisänen Riitta-Liisa Rajaniemi Leena E Saijonmaa-Koulumies 《Acta veterinaria Scandinavica》2009,51(1):40
Background
Demodex gatoi is unique among demodectic mites. It possesses a distinct stubby appearance, and, instead of residing in the hair follicles, it dwells in the keratin layer of the epidermis, causing a pruritic and contagious skin disease in cats. Little is known of the occurrence of D. gatoi in Europe or control of D. gatoi infestation. 相似文献53.
Alanen HI Williamson RA Howard MJ Hatahet FS Salo KE Kauppila A Kellokumpu S Ruddock LW 《The Journal of biological chemistry》2006,281(44):33727-33738
Protein folding and quality control in the endoplasmic reticulum are critical processes for which our current understanding is far from complete. Here we describe the functional characterization of a new human 27.7-kDa protein (ERp27). We show that ERp27 is a two-domain protein located in the endoplasmic reticulum that is homologous to the non-catalytic b and b' domains of protein disulfide isomerase. ERp27 was shown to bind Delta-somatostatin, the standard test peptide for protein disulfide isomerase-substrate binding, and this ability was localized to the second domain of ERp27. An alignment of human ERp27 and human protein disulfide isomerase allowed for the putative identification of the peptide binding site of ERp27 indicating conservation of the location of the primary substrate binding site within the protein disulfide isomerase family. NMR studies revealed a significant conformational change in the b'-like domain of ERp27 upon substrate binding, which was not just localized to the substrate binding site. In addition, we report that ERp27 is bound by ERp57 both in vitro and in vivo by a similar mechanism by which ERp57 binds calreticulin. 相似文献
54.
The Diversity and Anti-Microbial Activity of Endophytic Actinomycetes Isolated from Medicinal Plants in Panxi Plateau,China 总被引:1,自引:0,他引:1
Ke Zhao Petri Penttinen Tongwei Guan Jing Xiao Qiang Chen Jun Xu Kristina Lindström Lili Zhang Xiaoping Zhang Gary A. Strobel 《Current microbiology》2011,62(1):182-190
Traditional Chinese medicinal plants are sources of biologically active compounds, providing raw material for pharmaceutical,
cosmetic and fragrance industries. The endophytes of medicinal plants participate in biochemical pathways and produce analogous
or novel bioactive compounds. Panxi plateau in South-west Sichuan in China with its unique geographical and climatological
characteristics is a habitat of a great variety of medicinal plants. In this study, 560 endophytic actinomycetes were isolated
from 26 medicinal plant species in Panxi plateau. 60 isolates were selected for 16S rDNA-RFLP analysis and 14 representative
strains were chosen for 16S rDNA sequencing. According to the phylogenetic analysis, seven isolates were Streptomyces sp., while the remainder belonged to genera Micromonospora, Oerskovia, Nonomuraea, Promicromonospora and Rhodococcus. Antimicrobial activity analysis combined with the results of amplifying genes coding for polyketide synthetase (PKS-I, PKS-II)
and nonribosomal peptide synthetase (NRPS) showed that endophytic actinomycetes isolated from medicinal plants in Panxi plateau
had broad-spectrum antimicrobial activity and potential natural product diversity, which further proved that endophytic actinomycetes
are valuable reservoirs of novel bioactive compounds. 相似文献
55.
56.
Lindberg HK Korpi A Santonen T Säkkinen K Järvelä M Tornaeus J Ahonen N Järventaus H Pasanen AL Rosenberg C Norppa H 《Mutation research》2011,723(1):1-10
Toluene diisocyanate (TDI) and 4,4'-methylenediphenyl diisocyanate (MDI), used in the production of polyurethane foam, are well known for their irritating and sensitizing properties. Contradictory results have been obtained on their genotoxicity. We investigated the genotoxicity and protein binding of inhaled TDI and MDI in mice by examining micronucleated polychromatic erythrocytes (PCEs) in bone marrow and peripheral blood and TDI- and MDI-derived adducts in hemoglobin. Male C57Bl/6J mice (8 per group) were exposed head-only to TDI vapour (mean concentrations 1.1, 1.5, and 2.4mg/m(3); the mixture of isomers contained, on the average, 63% 2,4-TDI and 37% 2,6-TDI) or MDI aerosol (mean concentrations 10.7, 20.9 and 23.3mg/m(3)), during 1h/day for 5 consecutive days. Bone marrow and peripheral blood were collected 24h after the last exposure. Inhalation of TDI caused sensory irritation (SI) in the upper respiratory tract, and cumulative effects were observed at the highest exposure level. Inhalation of MDI produced SI and airflow limitation, and influx of inflammatory cells into the lungs. Hemoglobin adducts detected in the exposed mice resulted from direct binding to globin of 2,4- and 2,6-TDI and MDI, and dose-dependent increases were observed especially for 2,4-TDI-derived adducts. Adducts originating from the diamines of TDI (toluene diamine) or MDI (methylene dianiline) were not observed. No significant increase in the frequency of micronucleated PCEs was detected in the bone marrow or peripheral blood of the mice exposed to TDI or MDI. The ratio of PCEs and normochromatic erythrocytes (NCEs) was reduced at the highest concentration of MDI, and a slight reduction of the PCE/NCE ratio, dependent on cumulative inhaled dose, was also seen with TDI. Our results indicate that inhalation of TDI or MDI (1h/day for 5 days), at levels that induce toxic effects and formation of TDI- or MDI-specific adducts in hemoglobin, does not have detectable genotoxic effects in mice, as studied with the micronucleus assay. 相似文献
57.
A list of the 356 species of Cecidomyiidae (Diptera) recorded from Finland is presented, which comprises 6 Lestremiinae, 156 Micromyinae, 16 Winnertziinae, 69 Porricondylinae, and 109 Cecidomyiinae. The faunistic knowledge of Finnish Winnertziinae, Porricondylinae and Cecidomyiinae is regarded as particularly poor. Based on species numbers known from other countries in Europe, a conservative estimate is 700–800 species of Cecidomyiidae actually occurring in Finland. 相似文献
58.
Heli Nordgren Kirsi Aaltonen Tarja Sironen Paula M. Kinnunen Ilkka Kivist? Mirja Raunio-Saarnisto Anna-Maria Moisander-Jylh? Johanna Korpela Ulla-Maija Kokkonen Udo Hetzel Antti Sukura Olli Vapalahti 《PloS one》2014,9(10)
A new type of pyoderma was detected in Finnish fur animals in 2007. The disease continues to spread within and between farms, with severe and potentially fatal symptoms. It compromises animal welfare and causes considerable economic losses to farmers. A case-control study was performed in 2010–2011 to describe the entity and to identify the causative agent. Altogether 99 fur animals were necropsied followed by pathological and microbiological examination. The data indicated that the disease clinically manifests in mink (Neovison vison) by necrotic dermatitis of the feet and facial skin. In finnraccoons (Nyctereutes procyonoides), it causes painful abscesses in the paws. Foxes (Vulpes lagopus) are affected by severe conjunctivitis and the infection rapidly spreads to the eyelids and facial skin. A common finding at necropsy was necrotic pyoderma. Microbiological analysis revealed the presence of a number of potential causative agents, including a novel Streptococcus sp. The common finding from all diseased animals of all species was Arcanobacterium phocae. This bacterium has previously been isolated from marine mammals with skin lesions but this is the first report of A. phocae isolated in fur animals with pyoderma. The results obtained from this study implicate A. phocae as a potential causative pathogen of fur animal epidemic necrotic pyoderma (FENP) and support observations that the epidemic may have originated in a species -shift of the causative agent from marine mammals. The variable disease pattern and the presence of other infectious agents (in particular the novel Streptococcus sp.) suggest a multifactorial etiology for FENP, and further studies are needed to determine the environmental, immunological and infectious factors contributing to the disease. 相似文献
59.
High level of resistance to potato virus Y by expressing P1 sequence in antisense orientation in transgenic potato 总被引:2,自引:0,他引:2
60.