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1.
ZS Perényi O Szenci PV Drion H Banga-Mboko NM Sousa B El Amiri JF Beckers 《Reproduction in domestic animals》2002,37(6):324-329
Pregnancy‐associated glycoproteins (PAGs) isolated from the placenta of various ruminant species are enzymatically inactive members of the aspartic proteinase family. The measurement of these proteins in the maternal blood can be a good indicator of the presence of a live embryo. As certain aspartic proteinases are present in biological fluids in physiological and pathological conditions at various concentrations, it was necessary to determine the specificity of three radioimmunoassay (RIA) systems currently used for the detection of PAG molecules. Commercially available members of the aspartic proteinase family like pepsinogen, pepsin, chymosin, rennet, cathepsin D and renin were tested in a wide concentration range (10 ng/ml – 1 mg/ml). Pepsinogen cross‐reacted in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 50 μg/ml and 500 μg/ml concentrations, respectively. In the presence of pepsin, cross‐reaction was observed in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 500 μg/ml and 1 mg/ml concentrations, respectively. Chymosin and rennet could cross‐react in RIA 2 and RIA 3, while renin and cathepsin D did not decrease the binding of the tracer to antisera more, than that of the minimal detection limit. As the plasma/serum concentrations of the examined aspartic proteinases reported in the literature were outside the concentration range where cross‐reaction was observed, it can be concluded that these RIA systems were specific for the detection of PAGs in biological fluids. 相似文献
2.
Firas Talas Heiko K. Parzies Thomas Miedaner 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(1):39-48
Fusarium head blight (FHB) is one of the most destructive diseases of wheat. Twelve small commercial wheat fields (size 1–3
hectares) were sampled in Germany for Fusarium populations at three spots per field with 10 heads each. PCR assays using generic primers confirmed 338 isolates as F.graminearum sensu stricto (s.s.) (64.9%) out of 521 Fusarium spp. that were further analyzed. Populations of F. graminearum s.s. in Germany contain three types of trichothecenes with a dominancy of 15-acetyldeoxynivalenol chemotype (92%) followed
by 3-acetyldeoxynivalenol chemotype (6.8%) and a few isolates of nivalenol chemotype (1.2%). All these isolates were genotyped
using 19 microsatellite loci. The 12 populations showed a high genetic diversity within the small scale sampling areas resulting
in 300 different haplotypes. Genetic diversity within populations (71.2%) was considerably higher than among populations (28.8%)
as shown by analysis of molecular variance. Gene flow (Nm) between populations ranged from 0.76–3.16. Composition of haplotypes
of one population followed over 2 years changed considerably. No correlation between genetic and geographical distance was
found. In conclusion, populations of F. graminearum s.s. in Germany display a tremendous genetic variation on a local scale with a restricted diversity among populations. 相似文献
3.
By B. ZS. Kova&#; CS M. Gauly G. Stranzinger 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》1999,116(3):235-242
The present study involved three male lamas ( Lama glama ). Mitotic preparations from fibroblast culture and an electron microscopic observation on the synaptonemal complexes (Scs) were reported. Special attention was given to the morphology and behaviour of the chromosomes at the zygotene and pachytene substages of prophase I in primary spermatocytes from lamas. Analysis of mitotic preparations show diploid and triploid cells, with a relatively high frequency of polyploidy. Analyses of synaptonemal complexes in primary spermatocytes were carried out on 89 cells. Pairing abnormalities were only recorded in an average of 63% of the cells of the animal Tabasco. The other two animals were normal. The photographed cells give an upper limit estimate of the existing abnormalities, as there was a deliberate tendency towards selecting abnormal cells for photography. The presence of degenerating primary spermatocytes in SC preparations as well as in testicular sections, and the absence of spermatozoa in ejaculates confirm the chromosomally derived male sterility of one animal. 相似文献
4.
In this study, some biochemical changes of carp (Cyprinus carpio, Linnaeus 1758) tissues were investigated. Studies have been carried out on carp which have regional economical importance.
Storage temperature and time are the most important factors that affect the quality of fish during sales. It was observed
that the temperature varied between 9 and 12°C in sale conditions. In addition, we assumed the arrival time of the fish at
the fish market to be 0 (zero) h. Biochemical analyses [malondialdehyde (MDA) levels and catalase activity] of carp tissues
(muscle, liver, heart, spleen, brain) were carried out on fish which were held for 24 and 48 h, as well as on fresh fish
(0 h). In addition, sensory analysis was conducted by a panel consisting of experienced judges of sensory evaluation. Statistically
significant (P < 0.05) increases in MDA levels were found in liver, muscle, brain and spleen tissues when comparing the 0- and 24-h groups.
But there was no statistically significant (P > 0.05) increase in MDA level in heart tissue of carp after 24 h. There was a statistically significant (P < 0.05) increase in MDA levels in muscle, spleen and heart tissues when comparing the 24- and 48-h groups. In the group examined
at 24 h, it was observed that there were statistically significant differences from the 0 h group values (P < 0.05) for catalase (CAT) activity in muscle, brain, spleen and heart tissues. The decreases in CAT activity in liver and
spleen tissues were found to be statistically significant (P < 0.05) between the group examined at 24 h compared with the group examined at 48 h. Carp maintained good quality during
the selling conditions up to 24 h. This experiment deals with the effects of post-slaughter time and storage temperature on
carp tissues. It is concluded that by considering the storage temperature (9–12°C) and storage time (post-slaughter) the product
maintained acceptable quality up to 24 h. There was significant deterioration of sensory quality, as a result of changes in
chemical constituents. 相似文献
5.
This study was carried out to understand the preventive effect of selenium (Se4+) on heavy metal stress induced by lead and copper in rainbow trout (Oncorhynchus mykiss). Variation in glutathione peroxidase (Se-GSH-Px) and superoxide dismutase (SOD) activity, and in malondialdehyde (MDA) levels
in liver, spleen, heart, and brain tissues of rainbow trout after 72 h of exposure to Pb2+ and Cu2+ were investigated in the presence and absence of Se4+. In the presence of Se4+, Se-GSH-Px activity and SOD activity were found to be higher and MDA levels were lower compared with in its absence. Hematological
parameters were also determined and it has been observed that total leukocyte count (WBC), mean cell volume (MCV), and mean
cell hemoglobin (MCH) were increased and erythrocyte number (RBC), hemoglobin (Hb), and hematocrit value (Hct; P < 0.05) were decreased in fish exposed to heavy metals in the absence of selenium. Selenium presence recovered hematological
parameters to normal levels. In the light of our findings, it could be stated that Pb2+ and Cu2+ lead to dramatic changes in biochemical and hematological parameters and selenium caused these parameters to converge to
control levels when it was administered concurrently with these heavy metals. 相似文献
6.
7.
Thomas Miedaner Franciele Caixeta Firas Talas 《European journal of plant pathology / European Foundation for Plant Pathology》2013,137(4):743-752
Fusarium culmorum is a haploid, worldwide occurring phytopathogenic fungus causing seedling blight, foot rot, and head blight of cereals and producing the mycotoxins deoxynivalenol (DON) and nivalenol (NIV) associated with health hazards in human and animals. The fungus reproduces asexually by conidiospores, a teleomorph is not known. We analyzed for the first time naturally occurring F. culmorum populations collected randomly in the field from infected wheat heads. A total of 186 isolates, from three populations from Germany (GER), Russia (RUS), Syria (SYR), as well as an international collection (INT) for comparison, were genotyped by 10 microsatellite (SSR, single sequence repeat) markers. A high genetic diversity within the three natural populations and the INT population as well was detected. About 90 % of multi-locus haplotypes (MLH) were unique across populations. The largest part of variance (81 %) was found within populations. Accordingly, population subdivision was low, fixation indices were significant only in one out of six comparisons, while estimates of gene flow (N m ) ranged from 0.8–4.8. Linkage equilibrium was revealed by the index of multi-locus association and the quotient of observed and expected variance when two linked markers were deleted. DON and NIV chemotypes grouped closely together in a principle coordinate analysis. SYR isolates were partly separated from GER and RUS populations. All population-genetic parameters were in a similar range compared to those for the sexually propagating species F. graminearum. In conclusion, results support the hypothesis of a recombining structure in F. culmorum as revealed by the high genetic variation within populations, a low fixation index and low gametic phase disequilibrium within populations. 相似文献
8.
9.
Talas ZS Orun I Ozdemir I Erdogan K Alkan A Yilmaz I 《Fish physiology and biochemistry》2008,34(3):217-222
The main purpose of this study is to discuss the effect of Cd+2, Cr+3 and Se metals on biochemical parameters in liver tissue of Oncorhynchus mykiss. The rainbow trout were exposed to heavy metal stress (Cd+2, Cr+3) at 2 ppm dosage. The present study was undertaken to determine the protective effect of selenium treatment at the same dosage
(2 ppm) on some biochemical parameters. The activity of catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase
(SOD) and the changes in levels of malondialdehyde (MDA) from biochemical parameters were determined in liver tissue of the
fish groups exposed to heavy metals, especially for the selenium-applied groups. Results of this study showed that the activities
of CAT, GSH-Px and SOD in the tissues of fish exposed to the stress of Cd+2 and Cr+3 were significantly lower than the control groups (P < 0.05). Meanwhile, the closer values to the control groups were obtained in selenium-added groups (Cr+3 + Se+4, Cd+2 + Se+4). For the level of MDA, the last production of lipid peroxidation showed increases (P < 0.05) in the groups exposed to the metal stress, whereas significant decreases were obtained in selenium-applied groups.
The result of the statistical evaluation showed that the negative effects occurring in the biochemical parameters of the applied
groups exposed to the toxicity of heavy metal were significantly eliminated (P < 0.05) as a result of selenium treatment. 相似文献
10.
Fusarium head blight (FHB), caused by Fusarium graminearum sensu stricto (s.s.), causes tremendous annual yield losses in wheat worldwide. Variation of aggressiveness of isolates from individual field populations in terms of FHB infection and deoxynivalenol (DON) concentration in the host are important population parameters reflecting parasitic ability. Our main objective was to estimate the variation of both traits within three populations of F. graminearum s.s., each consisting of 30 single-spore isolates collected from small wheat fields in Germany, and to compare it with 11 isolates of a collection (F. graminearum collection) from four countries. The same isolates were characterized using 19 single-sequence repeat markers. All isolates were spray inoculated on a moderately resistant spring wheat cultivar at two field locations over 2 years (i.e., in four environments). The genotypic proportion of phenotypic variance (σ(2)(G)) within populations was significant (P < 0.01) for both traits, and the σ(2)(G) × environment interaction was even more important for mean FHB severity. Ranges in mean FHB severity and DON concentration in the host were only slightly smaller for the field populations than for the F. graminearum collection. Both traits were significantly (P < 0.05) correlated within and across populations. A further partitioning of σ(2)(G) revealed 72% of σ(2)(G) within and 28% of σ(2)(G) across populations for both traits. Molecular variance of the three populations was similarly distributed (73.6% within versus 26.4% between populations). In view of this high within-field variation for traits of parasitic ability and selection, neutral molecular markers, multiple resistance genes of different origin should be employed in wheat breeding programs to obtain a long-term stable FHB resistance. 相似文献