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1.
Thomas Arn Hansen Helena Fridholm Tobias Guldberg Fr?slev Kristín Rós Kjartansdóttir Eske Willerslev Lars Peter Nielsen Anders Johannes Hansen 《PloS one》2015,10(11)
Rattus norvegicus (R. norvegicus) are ubiquitous and their presence has several effects on the human populations in our urban areas on a global scale. Both historically and presently, this close interaction has facilitated the dissemination of many pathogens to humans, making screening for potentially zoonotic and emerging viruses in rats highly relevant. We have investigated faecal samples from R. norvegicus collected from urban areas using a protocol based on metagenomic enrichment of circular DNA genomes and subsequent sequencing. We found a new type of papillomavirus, with a L1 region 82% identical to that of the known R. norvegicus Papillomavirus 2. Additionally, we found 20 different circular replication associated protein (Rep)-encoding single stranded DNA (CRESS-DNA) virus-like genomes, one of which has homology to the replication-associated gene of Beak and feather disease virus. Papillomaviruses are a group of viruses known for their carcinogenic potential, and although they are known to infect several different vertebrates, they are mainly studied and characterised in humans. CRESS-DNA viruses are found in many different environments and tissue types. Both papillomaviruses and CRESS-DNA viruses are known to have pathogenic potential and screening for novel and known viruses in R. norvegicus could help identify viruses with pathogenic potential. 相似文献
2.
Mariana Mayer-Pinto Barbara L. Ignacio Maria T. M. Széchy Mariana S. Viana Maria P. Curbelo-Fernandez Helena P. Lavrado Andrea O. R. Junqueira Eduardo Vilanova Sérgio H. G. Silva 《PloS one》2012,7(10)
Several approaches have been proposed to assess impacts on natural assemblages. Ideally, the potentially impacted site and multiple reference sites are sampled through time, before and after the impact. Often, however, the lack of information regarding the potential overall impact, the lack of knowledge about the environment in many regions worldwide, budgets constraints and the increasing dimensions of human activities compromise the reliability of the impact assessment. We evaluated the impact, if any, and its extent of a nuclear power plant effluent on sessile epibiota assemblages using a suitable and feasible sampling design with no ‘before’ data and budget and logistic constraints. Assemblages were sampled at multiple times and at increasing distances from the point of the discharge of the effluent. There was a clear and localized effect of the power plant effluent (up to 100 m from the point of the discharge). However, depending on the time of the year, the impact reaches up to 600 m. We found a significantly lower richness of taxa in the Effluent site when compared to other sites. Furthermore, at all times, the variability of assemblages near the discharge was also smaller than in other sites. Although the sampling design used here (in particular the number of replicates) did not allow an unambiguously evaluation of the full extent of the impact in relation to its intensity and temporal variability, the multiple temporal and spatial scales used allowed the detection of some differences in the intensity of the impact, depending on the time of sampling. Our findings greatly contribute to increase the knowledge on the effects of multiple stressors caused by the effluent of a power plant and also have important implications for management strategies and conservation ecology, in general. 相似文献
3.
Margarida A. Ferreira M.Aurea Cruz Costa A.Correia Alves M.Helena Lopes 《Phytochemistry》1973,12(2):433-435
7-MethyljugIone, 8,8′-dihydroxy-4,4′-dimethoxy-6,6′-dimethyl-2,2′-binaphthyl-1,1′-quinone, 2-methylnaphthazarin, mamegakinone and euclein have been isolated from Euclea pseudebenus. Euclein is the 3,6′-dimer of 7-methyljuglone. 相似文献
4.
Marie Lipoldová Helena Havelková Jana Badalová Jarmila Vojtíšková Lei Quan Magdaléna Krulová Yahya Sohrabi Alphons P. Stassen Peter Demant 《Cancer immunology, immunotherapy : CII》2010,59(2):203-213
Low infiltration of lymphocytes into cancers is associated with poor prognosis, but the reasons why some patients exhibit
a low and others a high infiltration of tumors are unknown. Previously we mapped four loci (Lynf1–Lynf4) controlling lymphocyte infiltration of mouse lung tumors. These loci do not encode any of the molecules that are involved
in traffic of lymphocytes. Here we report a genetic relationship between these loci and the control of production of IFNγ
in allogeneic mixed lymphocyte cultures (MLC). We found that IFNγ production by lymphocytes of O20/A mice is lower than by
lymphocytes of OcB-9/Dem mice (both H2
pz
) stimulated in MLC by irradiated splenocytes of C57BL/10SnPh (H2
b
) or BALB/cHeA (H2
d
) mice, or by ConA. IFNγ production in MLCs of individual (O20 × OcB-9)F2 mice stimulated by irradiated C57BL/10 splenocytes and genotyped for microsatellite markers revealed four IFNγ-controlling
loci (Cypr4-Cypr7), each of which is closely linked with one of the four Lynf loci and with a cluster of susceptibility genes for different tumors. This suggests that inherited differences in certain
lymphocyte responses may modify their propensity to infiltrate tumors and their capacity to affect tumor growth. 相似文献
5.
6.
Silva Bruno Garcia Damianovic Márcia Helena Rissato Zamariolli Foresti Eugenio 《Bioprocess and biosystems engineering》2018,41(8):1115-1120
Bioprocess and Biosystems Engineering - This study assessed the simultaneous nitrification and denitrification processes and remaining organic matter removal from anaerobic reactor effluent... 相似文献
7.
Leonardo Mata Helena Gaspar Fátima Justino Rui Santos 《Journal of applied phycology》2011,23(5):827-832
The genus Asparagopsis is a prolific source of halogenated metabolites. Due to its commercial applications, it has been intensively cultivated in
southern Portugal. In the present study, we assess if the internal levels of the major halogenated metabolites (bromoform
and dibromoacetic acid) in Asparagopsis taxiformis can be increased with hydrogen peroxide (H2O2) addition. Previous studies with red algae showed that the production/release of bromoform can be enhanced by exogenously
supplying H2O2. However, no study has assessed if H2O2 supply enhances the content of secondary metabolites within the biomass. This detail is important as the objective of the
proposed research is to enhance the content of these valuable metabolites in the produced biomass. Both the activity of the
haloperoxidase enzyme and the metabolite content were assessed on short-term and long-term incubation periods to H2O2. To determine the susceptibility of A. taxiformis photosynthetic performance to the imposed oxidative stress, the in vivo fluorescence of photosystem II was monitored. A. taxiformis was shown to be physiologically vulnerable to H2O2, given the observed decrease of the maximum quantum yield of photosynthesis (F
v/F
m). Contrary to what was expected, the presence of H2O2 inhibited the activity of the iodoperoxidase enzyme. Nevertheless, the extracted halogenated metabolites were higher over
the first hours of exposure to H2O2, decreasing after 48 h. These results are probably related to the prosthetic group of the halogenated enzyme in A. taxiformis and the long-term oxidative stress damage of H2O2 exposure. Considering the objective of the proposed research, addition of H2O2 to the cultures, prior (3 h) to biomass harvesting, increases the metabolite content. 相似文献
8.
9.
Annikki Liakka Hanna Karjalainen Ismo Virtanen Helena Autio-Harmainen 《Cell and tissue research》1995,282(1):117-127
The distribution of the extracellular matrix proteins types III pN-collagen and IV collagen, laminin and tenascin was investigated in fetal, infant, and adult human spleens by using immuno-electron microscopy. The presence of type III pN-collagen was assessed by using an antibody against the aminoterminal propeptide of type III procollagen. All the proteins other than type III pN-collagen were found in reticular fibers throughout development. In the white pulp of the fetus aged 16 gestational weeks, only an occasional type III pN-collagen-containing fibril was present, although type III pN-collagen was abundant in the reticular fibers of the red pulp. Conversely, in adults, most of the reticular fibers of the white pulp, but not of the red pulp, were immunoreactive for type III pN-collagen. Ring fibers, the basement membranes of venous sinuses, were well developed in both infant and adult spleens. The first signs of their formation could be seen as a discontinuous basement membrane, which was immunoreactive for type IV collagen, laminin, and tenascin in the fetus aged 20 gestational weeks. Intracytoplasmic immunoreactivity for all the proteins studied was visible in the mesenchymal cells of the fetus aged 16 gestational weeks and in the reticular cells of the older fetuses, which also showed labeling for type IV collagen and laminin in the endothelial cells. The results suggest that proteins of the extracellular matrix are produced by these stationary cells. 相似文献
10.
The roles of allopatric fragmentation and niche divergence in intraspecific lineage diversification in the common midwife toad (Alytes obstetricans) 下载免费PDF全文