Sixty RAPD primers were used to screen for a diagnostic marker that could be used to identify Pyrenophora graminea , a fungal seedborne pathogen that causes leaf stripe on barley. Primer pairs were designed to differentiate P. graminea from other Pyrenophora spp. using a sequence-characterized amplified region (SCAR) approach. A pair of P. graminea -specific primers (PG2 F/R) was obtained that amplified a single fragment from 37 isolates of P. graminea tested, but not from 29 isolates of other Pyrenophora spp. or 12 saprophytes isolated from barley seed. Rapid PCR detection was achieved using a LightCycler, in which the emission of fluorescence from the binding of SYBR Green I dye to the PCR products is measured. The P. graminea -specific product resulting from amplification with PG2 F/R can be distinguished from any nonspecific products by post-PCR melting point analysis. The PCR assay involves 40 amplification cycles of PCR, and the total PCR test including melting point analysis takes 25 min to complete. The rapidity of this test, combined with the closed 'in-tube' detection of PCR products, which reduces the potential for contamination, offers significant advantages compared with conventional laboratory and PCR analyses. 相似文献
Plant trypanosomatids (Phytomonas spp) have been isolated from the crude sap of coconut tress and oil palm trees affected with Hartrot or Marchitex diseases in South America andAlpinia purpurata affected with wilt in the Caribbean. They are also commonly isolated from the fruits and latex of Euphorbiaceae or Asclepiadaceae. Thirty-fourPhytomonas stocks were studied by isoenzyme electrophoresis (11 loci) in order to investigate genetic variability in the intraphloemic group. Our results showed that variability in phloem restrictedPhytomonas is very high, and that Marchitez or Hartrot associated trypanosomatids are not readily separated into two distinct groups. Moreover, the two isolates fromAlpinia are very close to the other intraphloemic isolates. The results confirm the existence of several distinct groups, comprising of at least 2 groups of phloem restricted trypanosomatids, not related to the host species, 3 groups of latex trypanosomatids, and one group of fruit trypanosomatids. 相似文献
Two LHRH fusion proteins, thioredoxin and ovalbumin, each containing seven LHRH inserts were tested for their ability to inhibit estrous cycle activity. The objective was to evaluate immune and biological responses from alternating the two fusion proteins in an immunization schedule. One hundred ten heifers were divided equally into 11 groups. Two control groups consisted of either spayed or intact, untreated heifers. Heifers in the other nine groups were immunized on wk 0, 4, and 9. Treatments were immunizations of the same protein throughout or alternating the proteins in different booster sequences. Blood was collected weekly for 22 wk, and serum was assayed for concentrations of progesterone and titers of anti-LHRH. At slaughter, reproductive tracts were removed from each heifer and weighed. Heifers with >or=1 ng/mL of progesterone were considered to have a functional corpus luteum and thus to have estrous cycle activity. All LHRH-immunized groups of heifers had a smaller (P < 0.05) proportion of heifers showing estrous cycle activity after 6 wk than the intact, untreated control group. There was no difference in number of heifers cycling between the immunized groups and the spayed heifers during wk 9 to 22. Anti-LHRH did not differ among immunized groups during wk 1 to 9. Starting at wk 10 and continuing through the conclusion of the study, there was an overall difference among treatment groups for anti-LHRH (P < 0.05). Uterine weights differed among treatments (P < 0.05), with intact control animals having heavier uteri than all other groups (P < 0.05). Uterine weights were negatively correlated with maximum LHRH antibody binding (r = -0.44). In summary, the LHRH fusion proteins were as effective as surgical spaying in suppression of estrous cycle activity, but alternating the two proteins in an immunization schedule did not enhance the immunological or biological effectiveness of the vaccine. 相似文献
The aims of this study were to estimate the wastage of horses registered for eventing in Britain, to investigate the reasons for this wastage and to evaluate factors affecting the horses' achievement of grade I status (at least 61 points) while registered. An analysis of the database of the British Eventing register found that 33.7 per cent of horses registered for the first time in 1999 were not re-registered for eventing in subsequent years. By using multivariable logistic regression analysis, it was shown that horses that were kept at an event yard were more likely to be re-registered than those kept on other premises (odds ratio [or] 2.0, 95 per cent confidence interval [ci] 1.2 to 3.2), and those that took part in showjumping while registered were also more likely to be re-registered (or 1.5, 95 per cent ci 1.1 to 2.2). Horses that took part in unaffiliated eventing while registered were less likely to be re-registered the following year (or 0.7, 95 per cent ci 0.5 to 0.9), as were those that were not insured (or 0.7, 95 per cent ci 0.5 to 1.0) and those from outside the British Isles (or 0.6, 95 per cent ci 0.3 to 1.0). Veterinary problems were the most commonly cited explanation (35.1 per cent) why horses that remained in their original ownership were not re-registered with British Eventing the following year. Horses from Australia were more likely to achieve grade I status than horses from the British Isles (or 9.7, 95 per cent ci 7.1 to 13.2), as were horses from New Zealand (or 6.4, 95 per cent ci 5.0 to 8.2), the usa (or 5.2, 95 per cent ci 3.8 to 7.2) and France (or 2.8, 95 per cent ci 2.1 to 3.7), but horses from the Netherlands (or 0.5, 95 per cent ci 0.3 to 0.9) and Belgium (or 0.3, 95 per cent ci 0.1 to 0.9) were less likely to achieve grade I status. Mares were less likely to achieve grade I status than geldings (or 0.4, 95 per cent ci 0.4 to 0.5). 相似文献
REASONS FOR PERFORMING STUDY: Structural changes in articular cartilage associated with the ageing process require definition for investigators performing developmental and age-related studies, for which information is lacking. OBJECTIVES: To 1) determine the onset and end of puberty as defined by serum insulin like growth factor (IGF-I) and IGF-binding protein-3 (IGFBP-3) concentrations and 2) correlate articular-epiphyseal cartilage complex structural changes with the onset and end of puberty. METHODS: IGF-I and IGFBP-3 were measured in serum samples from normal female and male horses age 9-715 days to determine peak and steady-state values for horses transitioning through puberty. Osteochondral tissue sections were obtained from horses age 120-840 days (4-28 months) and examined histologically for cartilage canals and tidemark formation. RESULTS: In male and female horses, serum IGF-I/IGFBP-3 concentrations peaked at approximately 225 days, defining the onset of puberty. Cartilage canals were absent from articular cartilage just prior to this time point. IGF-I/IGFBP-3 concentrations declined to steady-state levels at approximately age 450 days, signalling exit from puberty and therefore the beginning of ageing. This time point correlated to initial formation of a tidemark in the osteochondral tissue sections. CONCLUSIONS: Horses may be considered pubescent at age 225-450 days, and post pubescent and ageing after age 450 days. POTENTIAL RELEVANCE: Defining the normal post natal to post pubescent concentrations for serum IGF-I and serum IGFBP-3 establishes subsets of animals for age-related studies and may be used to monitor horses for abnormally high IGF-I concentrations due to natural disease or subsequent to systemic growth hormone administration. 相似文献
Tomato spotted wilt virus was recorded for the first time in Jordan on tomato plants. Severe disease symptoms were observed in different tomato farms in the Jordan Valley. Using a specific primer pair a fragment of the capsid protein gene of the virus has been amplified by RT-PCR and IC-RT-PCR. The amplified PCR product was cloned and sequenced. Sequence analysis revealed that the Jordanian isolate of TSWV shared high nucleotide similarities with other isolates from different countries. The sequence of the capsid protein gene was deposited in GenBank under the accession number AY646682 . The response of different tomato breeding lines and hybrids, previously developed for resistance against Tomato yellow leaf curl virus (TYLCV) were tested for their reaction to TSWV infection. All tested lines and hybrids were susceptible to TSWV infection. This has been confirmed at the molecular level by using the SCAR 421 marker linked to the TSWV resistance gene Sw-5 . 相似文献
1. Ovomucoids were purified from Muscovy duck, domestic duck and domestic goose.
2. Peptide maps of cyanogen bromide‐cleaved ovomucoids from Muscovy duck and domestic duck were very similar to one another, but differed from that of goose.
3. Muscovy duck ovomucoid showed the same protease inhibitory pattern as ovomucoid from domestic duck, inhibiting trypsin in the molar ratio of 1:2 and chymotrypsin 1:1.
4. Inhibitory complexes could be detected between chymotrypsin and ovomucoid from both Muscovy and domestic duck, but not from goose, by using non‐denaturing gels.
5. No complexes could be detected between DFP‐inactivated chymotrypsin and any of the ovomucoids.
6. The results show that of ovomucoid from Muscovy duck more closely resembles that from domestic duck than goose. 相似文献
Two Old English Sheepdog littermates were evaluated for weakness that developed during periods of minimally intense exercise. Lactic acidosis accompanied by increased muscle enzyme activity, an increased lactate/pyruvate ratio, and increased venous PO2 supported the possibility of defective mitochondrial oxygen use. Electromyographic abnormalities included increased insertional activity and complex repetitive discharges. Muscle alterations included scattered myofiber necrosis, abundant endomysial connective tissue, excessive glycogen accumulation, and greater than normal numbers and vacuolation of mitochondria. A distinctive pattern of subsarcolemmal mitochondrial aggregates, referred to as "ragged red fibers" in human mitochondrial myopathies, was observed in muscle biopsy samples from 1 dog. Several features of the disease in these dogs, including onset of weakness during early life, simultaneous disease in littermates, subtle nonprogressive weakness of at least 3 years' duration, and partial reversibility of lactic acidosis following rest were suggestive of an inborn error of metabolism, consistent with mitochondrial myopathy. 相似文献
Experiences from the Mitigation Options for Phosphorus and Sediment (MOPS) projects, which aim to determine the effectiveness of measures to reduce pollutant loading from agricultural land to surface waters, have been used to contribute to the findings of a recent paper (Kay et al., 2009, Agricultural Systems, 99, 67-75), which reviewed the efficacy of contemporary agricultural stewardship measures for ameliorating the water pollution problems of key concern to the UK water industry. MOPS1 is a recently completed 3-year research project on three different soil types in the UK, which focused on mitigation options for winter cereals. MOPS1 demonstrated that tramlines can be the major pathway for sediment and nutrient transfer from arable hillslopes, and that although minimum tillage, crop residue incorporation, contour cultivation, and beetle banks also have potential to be cost-effective mitigation options, tramline management is the one of the most promising treatments for mitigating diffuse pollution losses, as it was able to reduce sediment and nutrient losses by 72-99% in four out of five site years trialled. Using information from the MOPS projects, this paper builds on the findings of Kay et al. to provide an updated picture of the evidence available and the immediate needs for research in this area. 相似文献