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411.
Andreas Fließbach Monika Messmer Bruno Nietlispach Valentina Infante Paul Mäder 《Biology and Fertility of Soils》2012,48(3):315-324
Genetically modified (GM) maize containing genes from the soil bacterium Bacillus thuringiensis (Bt) was cultivated on 29% of the total maize production area worldwide in 2009. Most studies to date compare Bt-maize varieties with their near isogenic lines; however, there is little information on the variability of conventional maize
breeding lines and how the effects of Bt varieties are ranked within. In our study on the potential risks of Bt-maize varieties, we analyzed tissue quality and compared the effects of ten conventional and GM maize varieties on soil microbiological
properties in a replicated climate chamber experiment. All maize varieties were cultivated twice in the same soil microcosm.
Shoot yields and soluble C in leaf tissue of Bt varieties were higher than the ones of non-Bt. Soil dehydrogenase activity was reduced by 5% under Bt varieties compared to non-Bt, while most of the other soil microbial properties (soil microbial biomass, basal respiration) showed no significant differences
between Bt and non-Bt varieties. The leaves and roots of one Bt variety were decomposed to a greater extent than the ones of its near isogenic line; the conventional breeding lines also
showed higher values. Changes in crop and soil parameters were found when comparing the first and the second crops, but the
effects of repeated cropping were the same for all tested varieties. For the studied parameters, the variation among non-Bt-maize varieties was similar to the difference between Bt and non-Bt varieties. 相似文献
412.
413.
Claudia Bachofen Hans-Rudolf Vogt Hanspeter Stalder Tanja Mathys Reto Zanoni Monika Hilbe Matthias Schweizer Ernst Peterhans 《Veterinary research》2013,44(1):32
Bovine viral diarrhoea virus (BVDV) is an economically important pathogen of cattle worldwide. Infection of a pregnant animal may lead to persistent infection of the foetus and birth of a persistently infected (PI) calf that sheds the virus throughout its life. However, BVD viruses are not strictly species specific. BVDV has been isolated from many domesticated and wild ruminants. This is of practical importance as virus reservoirs in non-bovine hosts may hamper BVDV control in cattle. A goat given as a social companion to a BVDV PI calf gave birth to a PI goat kid. In order to test if goat to goat infections were possible, seronegative pregnant goats were exposed to the PI goat. In parallel, seronegative pregnant goats were kept together with the PI calf. Only the goat to goat transmission resulted in the birth of a next generation of BVDV PI kids whereas all goats kept together with the PI calf aborted. To our knowledge, this is the first report which shows that a PI goat cannot only transmit BVD virus to other goats but that such transmission may indeed lead to the birth of a second generation of PI goats. Genetic analyses indicated that establishment in the new host species may be associated with step-wise adaptations in the viral genome. Thus, goats have the potential to be a reservoir for BVDV. However, the PI goats showed growth retardation and anaemia and their survival under natural conditions remains questionable. 相似文献
414.
Silvia Guil-Luna Librado Carrasco Jaime Gómez-Laguna Monika Hilbe Juan J. Mínguez Kernt K?hler Juana Martín de las Mulas 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(6):602-605
A cat was presented with right head tilt and circling. The lack of expression of virus antigens did not support the postmortem diagnosis of encephalomyelitis pointing to a diffuse primary central nervous system T-cell lymphoma on the basis of CD3 and CD45R co-expression with absence of CD79α staining. 相似文献
415.
Joanna PIASECKA-SRADER Agnieszka SADOWSKA Anna NYNCA Karina ORLOWSKA Monika JABLONSKA Olga JABLONSKA Brian K. PETROFF Renata E. CIERESZKO 《The Journal of reproduction and development》2016,62(1):103-113
Low doses of endocrine disrupting chemicals (EDCs) used in combination may act in a manner different from
that of individual compounds. The objective of the study was to examine in vitro effects of
low doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; 100 pM) and genistein (500 nM) on: 1)
progesterone (P4) and estradiol (E2) secretion (48 h); 2) dynamic changes in aryl
hydrocarbon receptor (AhR) mRNA and protein expression (1, 3, 6, 24 and 48 h); 3) dynamic changes in estrogen
receptor β (ERβ) mRNA and protein expression (1, 3, 6, 24 and 48 h); and 4) induction of apoptosis in porcine
granulosa cells derived from medium follicles (3, 6 and 24 h). TCDD had no effect on P4 or
E2 production, but potentiated the inhibitory effect of genistein on P4 production. In
contrast to the individual treatments which did not produce any effects, TCDD and genistein administered
together decreased ERβ and AhR protein expression in granulosa cells. Moreover, the inhibitory effect of TCDD
on AhR mRNA expression was abolished by genistein. The treatments did not induce apoptosis in the cells. In
summary, combined effects of low concentrations of TCDD and genistein on follicular function of pigs differed
from that of individual compounds. The results presented in the current paper clearly indicate that effects
exerted by low doses of EDCs applied in combination must be taken into consideration when studying potential
risk effects of EDCs on biological processes. 相似文献
416.
417.
418.
Gabrielska J Soczyńska-Kordala M Przestalski S 《Journal of agricultural and food chemistry》2005,53(1):76-83
The work investigates the possibility of the protective action of kaempferol on phosphatidylcholine liposome membranes exposed to the pro-oxidative action of diphenyltin dichloride (DPhT) and triphenyltin chloride (TPhT) induced by UV radiation (lambda = 253.7 nm). The concentrations of kaempferol and its equimolar mixtures with DPhT and TPhT were determined so that they induce 50% inhibition in oxidation of liposomes irradiated with UV. They are 11.6, 10.0, and 4.5 microM/L, which constitute the following sequence of antioxidative activity: kaempferol/triphenyltin > kaempferol/diphenyltin > kaempferol. This relationship is confirmed by the results on the antiradical ability of kaempferol and its mixtures with DPhT and TPhT toward the free radical 2,2-diphenyl-1-picrylhydrazyl. Similar sequences obtained in both studies suggest a possible mechanism of the antiradical action of the mixtures as free radical scavengers. Kaempferol's ability, then documented, to form complexes with phenyltins indicates (a) a possible way to liquidate the peroxidation caused by the free radical forms of phenyltins and (b) the stabilizing role of chelating in the antioxidative action of the kaempferol/phenyltins. The differentiation in the action of the compounds studied may, among others, result from different localizations in the liposome membrane, which is indicated by the results of the fluorometric studies. 相似文献
419.
Monika Fecury Moura Tatiana Mituti Julio M. Marubayashi Ricardo Gioria Romulo F. Kobori Marcelo A. Pavan Norberto da Silva Renate Krause-Sakate 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(4):549-552
Pepper yellow mosaic virus (PepYMV) is the most important potyvirus infecting sweet pepper in Brazil. In this study, twenty isolates of PepYMV were
obtained from commercial sweet pepper crops. To confirm virus identity, the coat protein gene was completely sequenced for
eleven of these isolates, and partially sequenced for the other nine isolates. The amino acid identities obtained were above
93% when compared with the sequence of a characterized PepYMV isolate (AF348610). Extracts of Nicotiana tabacum cv. TNN plants infected with the different isolates were used to inoculate the differential series of Capsicum spp cultivars containing the genes pvr2
1
, pvr2
2
, pvr2
3
, pvr2
4
, and Pvr4. Using the same criteria established for Potato virus Y (PVY), fourteen isolates of PepYMV could be classified as known pathotypes described for PVY, that is: 1.2 (2 isolates),
1.3 (6) and 1.2.3 (6). The remaining six isolates, 1.3 (2) and 1.2.3 (4) could not be classified into the typical pathotypes
of PVY because they were also virulent on Serrano Criollo de Morellos—334 (C.M 334) which carries the pvr2
3
and Pvr4 genes. To classify the PepYMV into pathotypes and counter the biological diversity found in this species we propose the utilization
of 2x for the ability to overcome the correspondent allele of the pvr2 locus and 4 for the capacity to break down the Pvr4 gene. Using this criterion we could classify the PepYMV into five pathotypes: 21.22; 21.23; 21.22.23; 21.23. 4 and 21.22.23. 4. 相似文献
420.
Gołkowski F Buziak-Bereza M Trofimiuk M Bałdys-Waligórska A Szybiński Z Huszno B 《Public health nutrition》2007,10(8):799-802
OBJECTIVE: To assess the prevalence of hyperthyroidism just after implementation of iodine prophylaxis among adults from an area with iodine deficiency. STUDY DESIGN AND SUBJECTS: A total of 1648 adults (age 16 years and older) were sampled from an area of southern Poland during two nationwide epidemiological surveys. Of these, 1424 adults with negative medical history for thyroid disorders qualified for final analysis. The authors compared thyroid dysfunction in participants prior to (1989-1990) and after implementation of iodine prophylaxis (1997-1999). SETTING: The southern part of Poland. RESULTS: We found an increase in the serum concentration of anti-thyroid microsomal antibodies from 4.9% in the years 1989-1990 to 12.1% after introduction of iodised household salt (P < 0.0001). The prevalence of hyperthyroidism (defined as thyroid-stimulating hormone < 0.4 microU ml- 1) significantly increased in the equivalent period from 4.8 to 6.5% (P = 0.009). CONCLUSIONS: We concluded that a sudden rise in iodine intake after implementation of iodine prophylaxis among adults from the area with iodine deficiency may lead to an increase in thyroid autoimmunity and prevalence of hyperthyroidism. Those possible early side-effects appear to be only temporary and are acceptable when compared with the evident benefits of adequate iodine intake. 相似文献