Expression of porcine endogenous retroviruses (PERVs) in melanomas of Munich miniature swine (MMS) Troll   总被引：1，自引：0，他引：1  

Dieckhoff B  Puhlmann J  Büscher K  Hafner-Marx A  Herbach N  Bannert N  Büttner M  Wanke R  Kurth R  Denner J 《Veterinary microbiology》2007,123(1-3):53-68

Porcine endogenous retroviruses (PERVs) are integrated in the genome of all pig breeds. Since some of them are able to infect human cells, they might represent a risk for xenotransplantation using pig cells or organs. However, the expression and biological role of PERVs in healthy pigs as well as in porcine tumours is largely unknown. Since we and others have recently shown overexpression of a human endogenous retrovirus, HERV-K, in human melanomas, we studied the expression of PERVs in melanomas of selectively bred Munich miniature swine (MMS) Troll. This breeding herd of MMS Troll is characterised by a high prevalence of melanomas, which histologically resemble various types of cutaneous melanomas in humans. Several genetic factors have been defined when studying inheritance of melanomas and melanocytic nevi in MMS Troll. Here we show that the polytropic PERV-A and PERV-B as well as the ecotropic PERV-C are present in the genome of all melanoma bearing MMS Troll investigated. Most interestingly, in the spleen, but not in other organs, recombinant PERV-A/C proviruses were found. PERV expression was found elevated in melanomas when compared to normal skin and viral proteins were expressed in melanomas and pulmonary metastasis-derived melanoma cell cultures. During passaging of these cells in vitro the expression of PERV mRNA and protein increased and virus particles were released as shown by RT activity in the supernatant and by electron microscopy. Genomic RNA of PERV-A, -B and -C were found in pelleted virus particles. Although PERV expression was elevated in melanomas and pulmonary metastasis-derived cell cultures, the function of the virus in tumour development is still unclear.  相似文献   

Phylogenetic characterization of rabies virus isolates from Carnivora in Brazil     

Kobayashi Y  Inoue N  Sato G  Itou T  Santos HP  Brito CJ  Gomes AA  Santos MF  Silva MV  Mota CS  Ito FH  Sakai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(7):691-696

The incidence of canine rabies has been widely reported in Brazil, and new rabies virus (RV) variants, genetically similar to canine RV, have recently been isolated from foxes. In order to derive the epidemiological characteristics of Brazilian Carnivora RV, Brazilian RVs isolated from dogs, cats, and foxes were genetically analyzed. Brazilian Carnivora RV isolates were divided into 2 main lineages. The predominant lineage was found in dogs and cats, which included the Argentinean and Bolivian Carnivora RV isolates, and was extensively distributed throughout Brazil and surrounding countries. The other lineage consisted of three sublineages containing Brazilian dog and fox RV isolates, with the dog sublineages located on an internal branch of 2 fox sublineages, suggesting that RV transmission events might have occurred between foxes and dogs in the past. These results suggest that contact between dogs and wildlife has the potential to generate new rabies variants and that it is important to control RV infection cycles in both dogs and wildlife to prevent spread of rabies infection.  相似文献   

Unraveling the morphological patterns of a subantarctic eelpout: a geometric morphometric approach     

Fernanda S. ORREGO  Mathias HÜNE  Hugo A. BENÍTEZ  Mauricio F. LANDAETA 《Integrative zoology》2023,18(2):372-384

Phenotypic variation in organisms depends on the genotype and the environmental constraints of the habitat that they exploit. Therefore, for marine species inhabiting contrasting aquatic conditions, it is expected to find covariation between the shape and its spatial distribution. We studied the morphology of the head and cephalic sensory canals of the eelpout Austrolycus depressiceps (4.5–22.5 cm TL) across its latitudinal distribution in South Pacific (45°S–55°S). Geometric morphometric analyses show that the shape varied from individuals with larger snout and an extended suborbital canal to individuals with shorter snouts and frontally compressed suborbital canal. There was size variation across the sampled populations, but that size does not have a clear latitudinal gradient. Only 8% of the shape variation relates to this size variation (allometry), represented by a decrease in the relative size of the eye, and a depression of the posterior margin of the head. There were spatial differences in the shape of the head, but these differences were probably caused by allometric effects. Additionally, 2 of the canals of the cephalic lateralis pores and the head shape showed modularity in its development. This study shows that the morphology of marine fish with a shallow distribution varies across distances of hundreds of kilometers (i.e., phenotypic modulation).  相似文献   

Development of <Emphasis Type="Italic">Peronospora parasitica</Emphasis> epidemics on radish as modelled by the effects of water vapour saturation deficit and temperature     

Andreas Kofoet  Mathias Fink 《European journal of plant pathology / European Foundation for Plant Pathology》2007,117(4):369-381

Epidemics of Peronospora parasitica are strongly affected by temperature and air moisture, and the interaction of these factors. Because a significant percentage of radish plants are grown in greenhouses, it may be possible to influence epidemics by altering the greenhouse climate. The objective of this study was to test the hypothesis that epidemics of P. parasitica can be modelled by the effects of air temperature and moisture in the greenhouse. Such a model could then be used to analyse greenhouse climate control strategies with regard to managing downy mildew. Five radish crops were grown under greenhouse conditions with set-points for heating and ventilation intended to obtain favourable conditions for disease development during the first part of the growing cycle. Subsequent to this first phase, unfavourable conditions were set until harvest. Disease incidence was measured once a week until the radishes reached marketable size. In addition, experiments were carried out in growth chambers in which inoculated plants were subjected to air temperatures between 8 and 27°C, and disease incidence and sporulation intensity were measured. Data from these two experiments were then used to estimate model parameters. In this model, the interactions of air temperature (T) and water vapour saturation deficit (SD) were adequately described by a multiplicative relationship. The simulated epidemics by the fitted model were highly correlated with the observed epidemics (r = 0.91, R ² = 0.83, n = 29). Parameter estimates indicated that T of ca. 20°C and SD < 0.03 hPa resulted in the highest rates of disease development and that the rate was zero when SD > 2.0 hPa. Both experimental data and simulations showed that epidemics of P. parasitica can be effectively controlled by managing the greenhouse climate.  相似文献   

Associations among Haemophilus parasuis,Mycoplasma hyorhinis,and porcine reproductive and respiratory syndrome virus infections in pigs with polyserositis     

Andreas Palzer  Kristina Haedke  Karl Heinritzi  Susanne Zoels  Andrea Ladinig  Mathias Ritzmann 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(3):285-287

The objective of this study was to determine the associations among Haemophilus parasuis, Mycoplasma hyorhinis, and porcine reproductive and respiratory syndrome (PRRS) virus (EU-field strain) infections in 95 pigs with polyserositis. A significant association between H. parasuis and M. hyorhinis was identified. H. parasuis and M. hyorhinis were significantly more often detected in PRRS virus positive pigs.  相似文献   

Kinetic modeling of malonylgenistin and malonyldaidzin conversions under alkaline conditions and elevated temperatures     

Vaidya NA  Mathias K  Ismail B  Hayes KD  Corvalan CM 《Journal of agricultural and food chemistry》2007,55(9):3408-3413

The conversion and degradation of malonylglucosides were kinetically characterized under elevated pH/heat conditions. Malonylgenistin and malonyldaidzin were heated at 60, 80, and 100 degrees C and pH values of 8.5, 9, and 9.5. A simple kinetic model was developed, which adequately predicted the conversion and degradation reactions. The conversion and degradation rates increased as temperature and pH increased. The rates of conversion of both malonylglucosides into their respective beta-glucosides were comparable under all pH/heat treatments. However, at 100 degrees C, the rates of degradation of malonyldaidzin were approximately double those of malonylgenistin, under all pH treatments. When malonlydaidzin was heated at 100 degrees C and pH 9.5, degradation of the produced daidzin occurred. Therefore, an alternative kinetic model was developed to better predict the conversion and degradation of malonyldaidzin occurring at 100 degrees C and pH 9.5. The models developed provide soy food manufacturers with guidelines for better control of the profile and level of isoflavones..  相似文献   

Crown allometry and growing space requirements of four rare domestic tree species compared to oak and beech: implications for adaptive forest management     

Schmucker  Julia  Uhl  Enno  Steckel  Mathias  Pretzsch  Hans 《European Journal of Forest Research》2022,141(4):587-604

European Journal of Forest Research - Rare domestic tree species are increasingly being viewed as promising alternatives and additions to current main tree species in forests facing climate change....  相似文献   

Functional investigation of a QTL affecting resistance to Haemonchus contortus in sheep     

Guillaume Sallé  Carole Moreno  Simon Boitard  Julien Ruesche  Aurélie Tircazes-Secula  Frédéric Bouvier  Mathias Aletru  Jean-Louis Weisbecker  Fran?oise Prévot  Jean-Paul Bergeaud  Cathy Trumel  Christelle Grisez  Emmanuel Liénard  Philippe Jacquiet 《Veterinary research》2014,45(1):68

This study reports a functional characterization of a limited segment (QTL) of sheep chromosome 12 associated with resistance to the abomasal nematode Haemonchus contortus. The first objective was to validate the identified QTL through the comparison of genetically susceptible (N) and resistant (R) sheep produced from Martinik × Romane back-cross sheep. The R and N genotype groups were then experimentally infected with 10 000 H. contortus larvae and measured for FEC (every three days from 18 to 30 days post-challenge), haematocrit, worm burden and fertility. Significant differences in FEC and haematocrit drop were found between R and N sheep. In addition, the female worms recovered from R sheep were less fecund. The second step of the characterization was to investigate functional mechanisms associated with the QTL, thanks to a gene expression analysis performed on the abomasal mucosa and the abomasal lymph node. The gene expression level of a candidate gene lying within the QTL region (PAPP-A2) was measured. In addition, putative interactions between the chromosome segment under study and the top ten differentially expressed genes between resistant MBB and susceptible RMN sheep highlighted in a previous microarray experiment were investigated. We found an induction of Th-2 related cytokine genes expression in the abomasal mucosa of R sheep. Down-regulation of the PAPP-A2 gene expression was observed between naïve and challenged sheep although no differential expression was recorded between challenged R and N sheep. The genotyping of this limited region should contribute to the ability to predict the intrinsic resistance level of sheep.  相似文献   

Geomorphological stream channel classification in aquatic habitat restoration: Uses and limitations     

G. Mathias Kondolf 《水产资源保护:海洋与淡水生态系统》1995,5(2):127-141

• 1 Land managers in western North America have embraced classification of stream channels based on geomorphological characteristics as the importance of channel stability in successful restoration of aquatic and riparian habitat has become widely recognized.
• 2 Classification can permit rapid inventory of large regions, provide a stratified geomorphological framework within which more detailed observations can be organized, and provide an initial basis for selecting restoration strategies.
• 3 Existing classifications are arbitrary, developed by creating classes out of a continuum of channel form. Moreover, stream channels are dynamic, and the existing condition does not necessarily reflect former, long-term, or future conditions.
• 4 The user should not confuse the classification exercise with a complete understanding of the channel. Before any channel works are actually undertaken, site-specific studies are essential, including historical studies to determine former channel conditions and to shed light on underlying causes for degradation of aquatic or riparian resources.
• 5 When applying a classification system, the raw data collected should be reported, not simply the resultant channel classes. Channels that do not fit neatly within pre-existing classes should be reported as such and not lumped in classes where they ?should’? be.

  相似文献   

巴西迈出植物认证第一步     

朱海军 《中国花卉园艺》2006,(23):49

目前,随着人们质量意识的逐渐提高,急需建立一套植物认证体系来证明种植者已经遵守了某种标准,并且在这个标准下种植者生产的产品质量能够达到已制定的目标。今年5月,在巴西莫卡花卉市场(Mercaflora Markrt)举办的第十届花卉论坛上,官方正式启动了这一植物认证体系,巴西南部的圣卡塔林纳州成为这项国家计划的试点。圣卡塔林纳是一个传统的生产景观植物的地区,历来以创新闻名。巴西的花卉研究所也建于该地。该项植物认证的实施方式有两种,一种是由联合机构规定产业标准和产品质量;另一种是根据农业部的相关规定,政府授权认证机构。其中认证…  相似文献