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ABSTRACT Twenty-one strains of Botrytis cinerea isolated from 13 species of plants grown in China were compared for pathogenicity on Brassica napus, mycelial growth on potato dextrose agar, and presence of double-stranded (ds)RNA. The results showed that the strain CanBc-1 was severely debilitated in pathogenicity and mycelial growth, compared with the 20 virulent strains. A dsRNA of approximately 3.0 kb in length was detected in CanBc-1 and 4 hypovirulent single-conidium (SC) isolates of CanBc-1, but was not detected in the 20 virulent strains of B. cinerea and 4 virulent SC isolates of CanBc-1. Results of the horizontal transmission experiment showed that the hypovirulent trait of CanBc-1 was transmissible and the 3.0-kb dsRNA was involved in the transmission of hypovirulence. Analysis of a 920-bp cDNA sequence generated from the 3.0-kb dsRNA of CanBc-1 indicated that the dsRNA element was a mycovirus, designated as B. cinerea debilitation-related virus (BcDRV). Further analyses showed that BcDRV is closely related to Ophiostoma mitovirus 3b infecting O. novo-ulmi, the causal agent of Dutch elm disease. Mitochondria and cytoplasm in hyphal cells of CanBc-1 became degenerated, compared with the virulent isolate CanBc-1c-66 of B cinerea. This is the first report on the occurrence of Mitovirus-associated hypovirulence in B. cinerea. 相似文献
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Hso-Chi Chaung Tzou-Chi Huang Jou-Hui Yu Mei-Li Wu Wen-Bin Chung 《Veterinary immunology and immunopathology》2009,131(3-4):147-157
The immunopharmacological activities of β-glucans with a backbone of β-1,3/β-1,6-linkages associated with anti-tumor, anti-viral, bacterial and fungal infections have been well documented. Dectin-1, a specific pattern recognition receptor for β-1,3/β-1,6-glucans, is expressed mainly on phagocytes, especially macrophages and dendritic cells (DCs). In this study, the encoding nucleotide for the carbohydrate-recognition domain (CRD) of porcine dectin-1 was sequenced for the first time, and the immunomodulatory functions of a synthetic particulate β-glucan (p-β-glucan) were examined. Results showed that p-β-glucan significantly enhanced cell activity and phagocytosis in porcine alveolar macrophages (AMs), immature DCs (imDCs) and mature DCs (mDCs), in a similar way to zymosan. Zymosan enhanced dectin-1/TLR2/TLR4 expression and TNF-α/IL-10 production in all of three types of cell, whereas p-β-glucan increased dectin-1/TLR4 and TNF-α/IL-12 production in AMs but inhibited IL-10 in mDCs. These results indicate that the complex collaborating interactions between dectin-1 and TLRs in the recognition of β-1,3/β-1,6-glucans with different structural features may direct different cellular responses. 相似文献
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Chang SC Chen HF Chou MH Wang HC Su HY Wong ML 《Veterinary and comparative oncology》2010,8(4):302-309
Four types of globins for oxygen transport are known in vertebrates, and the haemoglobin is responsible for carrying oxygen in blood. In this study, we found that haemoglobin was also expressed in canine mammary glands. Samples were taken from 26 malignant mammary tumors, 16 normal mammary glands and 10 other normal tissues. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), immunoblotting and mass spectrometry were used to investigate haemoglobin in mammary tissues. The results indicated that normal canine mammary glands expressed high levels of haemoglobin protein as shown by Coomassie blue staining. The identity of haemoglobin was confirmed by immunoblotting and mass spectrometry, and the mass spectrometry data revealed that both alpha-haemoglobin and beta-haemoglobin were expressed. Relative to normal mammary glands, the levels of haemoglobin expression in mammary tumors were lower. Our results also indicated that the haemoglobin was endogenously produced in mammary gland tissues and was not derived from the erythroid cells. 相似文献
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Tunved P Hansson HC Kerminen VM Ström J Maso MD Lihavainen H Viisanen Y Aalto PP Komppula M Kulmala M 《Science (New York, N.Y.)》2006,312(5771):261-263
Aerosols play a key role in the radiation balance of the atmosphere. Here, we present evidence that the European boreal region is a substantial source of both aerosol mass and aerosol number. The investigation supplies a straightforward relation between emissions of monoterpenes and gas-to-particle formation over regions substantially lacking in anthropogenic aerosol sources. Our results show that the forest provides an aerosol population of 1000 to 2000 particles of climatically active sizes per cubic centimeter during the late spring to early fall period. This has important implications for radiation budget estimates and relevancy for the evaluation of feedback loops believed to determine our future climate. 相似文献
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The effects of blocking polar body I (PB1) or polar body II (PB2) with four different dosages of cytochalasin B (CB) on the development and ploidy of resultant embryos were studied in the small abalone, Halitis diversicolor supertexta (Lischke). To block the release of PBI, the fertilized eggs were treated with 0.25, 0.5, 1.0 or 2.0 mgL?1 of CB for 10min beginning at 3 min post-fertilization at 24°C. To block the release of PB2, the fertilized eggs were treated under the same conditions as PB1, except that the treatment was begun 10min post-fertilization. In the control group, only 41.8% of the cells had a diploid number of 32 chromosomes, although spontaneous haploids (9.0%). tripolids (7.5%) and aneuploids (41.7%) were also observed. In CB treatment of PB1 and PB2 groups. 5.0-28.6% of the cells remained as diploid. triploids (10.0-18.9%) and aneuploids (41-1-61.0%). With regard to the development of the resultant embryos, the proportion of normal embryos in the control group was 87%, while in the treatment groups, the proportions of normal embryos in the FBI and PB2 groups were 57-58% and 53-56% in the 0.25 mg L?1 and 0.5mg L?1 CB treatments, respectively. From this data on induced triploids and the resultant development of normal embryos, the proportions suggest that 0.25-0.5 mg L?1 of CB for 10min was sufficient for blocking the release of FB1 or PB2 to produce triploids in the small abalone. 相似文献
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Buehl IE Prosl H Mundt HC Tichy AG Joachim A 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2006,53(10):482-487
Isospora spp. are the causative agents of canine isosporosis. Of the 3590 diagnostic samples from Austrian dogs (< or = 2 years old), 8.7% contained Isospora oocysts, 78% of which from dogs up to 4 months of age. Non-haemorrhagic and haemorrhagic diarrhoea were significantly more prevalent in Isospora-infected animals than in coccidia-negative ones. Twelve of 15 litters from a large commercial dog breeding unit (examined from the third to the 10th week of life) also excreted Isospora (average prevalence: 36.4%) in intensities from 333 to 35,000 oocysts per gram of faeces (opg). In experimental trials 26 3-week-old Beagle puppies were infected with low (600-6000), medium (10,000) or high (20,000) dose of Isospora ohioensis-group or Isospora canis field isolates. Additionally 21 puppies were infected as above and treated with a symmetrical triazintrione. Parasitological and clinical parameters were examined. The two Isospora species differed significantly concerning intensity and duration of excretion. The pre-patent period was 6-7 days for I. ohioensis and 10-12 days for I. canis. The latter species showed significantly longer excretion and higher opg. This was not influenced by simultaneous infections with both species. Individual patterns of faecal consistency were very variable, irrespective of the infection dose. Treatment significantly reduced both the intensity and the duration of oocysts excretion as well as diarrhoea in comparison with the infected, untreated group and thus proved to be effective against coccidiosis in experimental infections. 相似文献
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Kim CH Lee CG Yoon HC Nam HM Park CK Lee JC Kang MI Wee SH 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2006,53(3):111-115
Since the first rabies case was reported in a dog in 1907, the disease was enzootic up to 1975 in Korea. After a steady decrease in the number of rabies cases from 1976 to 1984, no case was reported for 8 years from 1985 to 1992. Then, a resurgence of the disease was noted in 1993, and a continuous increase of rabies cases was observed during the following years. This report provides information on rabies in South Korea during the reemerging period 1993-2003. A total of 364 rabies cases in five different animal species and five deaths in human beings as a result of rabies were reported. Cattle and dogs accounted for 46.4% and 40.4% of total animal cases, respectively, and raccoon dogs commanded an overwhelming majority (44/48) of rabies cases in wildlife animal species. All animal and human rabies cases occurred only in two provinces, Gyeonggi and Gangwon; majority of them in two counties of Gyeonggi and one county of Gangwon province that border the demilitarized zone. From the three counties, the disease continued to expand to the other areas of the two provinces. The average monthly frequency of animal rabies cases during the 11-year period peaked in January, and the incidence was highest during winter. There were three major rabies outbreaks in animals and the number of animal rabies cases increased with time. Data indicate that the temporal patterns were attributable to the ethology of raccoon dogs in the areas of outbreak. 相似文献