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51.
Twenty-eight strains of Pseudomonas syringae pv. actinidiae isolated in 1984, 1987 and 1988 from kiwifruit orchards in Japan were tested for their resistance to copper sulfate. All strains isolated in 1984 were copper sensitive with a minimum inhibitory concentration (MIC) of cupric sulfate of 0.75 mM. However, some strains isolated in 1987 and 1988 were resistant, with the MIC ranging from 2.25 to 3.0 mM. All copper-resistant strains contained at least one of two plasmids, pPaCul (about 70.5 kb) or pPaCu2 (about 280 kb), or both. In a copper-resistant strain Pa429, the location of the copper-resistance gene(s) was examined by insertional inactivation with Tn5. The MIC of copper sulfate in the copper-sensitive mutant obtained by Tn5 tagging decreased from 2.75 to 0.75 mM. The 14.5 kb BamHI fragment, designated pPaCuB14, containing the same locus mutagenized with Tn5 was cloned from pPaCu1. However, pPaCuB14 did not confer copper resistance in the transformant of copper-sensitive strain Pa21R, suggesting that this clone did not contain a full set of copper-resistance gene(s). Then a cosmid library of pPaCu1 was constructed and six cosmid clones hybridized with pPaCuB14 were selected. One of the six cosmids, designated pPaCuC1, conferred a near wild-type level of copper resistance in the transformant of the copper-sensitive strain. pPaCuC1 had a homologous region that hybridized with all of the PCR-amplifled fragments of copA, copB, copR, and copS genes of P. syringae pv. tomato. DNA sequence analysis of the homologous region revealed the existence of four open reading frames (ORF A, B, R and S) oriented in the same direction. The predicted amino acid sequences of ORF A, B, R and S had 80, 70, 97 and 95% identity with CopA, B, R and S of P. syringae pv. tomato, respectively. Received 5 July 2001/ Accepted in revised form 27 September 2001  相似文献   
52.
Fifty-five canine parvovirus type 2 (CPV) samples, 12 fecal specimens and 43 cell culture isolates, were examined for their genetic characteristics of VP2 gene. They were collected from the diseased dogs at various districts of Japan during 27 years from 1980 to 2006. A fragment of VP2 gene was analyzed by restriction fragment length polymorphism assay and DNA sequencing. The original antigenic type 2 of CPV (CPV-2) was no longer found in the samples since 1984, and two antigenic variants CPV-2a and CPV-2b replaced CPV-2 as predominant types for about 5 years from 1982. A new genetic variant of prototype CPV-2a with non-synonymous substitution at the VP2 amino acid residue 297 from Ser to Ala was first detected in 1987. New CPV-2b with the same amino acid substitution at position 297 as new CPV-2a was also detected from the samples collected in 1997. Since then new CPV-2b has been the predominant CPV over the field of Japan. Several additional amino acid substitutions were detected in the VP2 gene of some recent CPV strains. Neither CPV-2c(a), CPV-2c(b), nor "Glu-426" of the antigenic variants previously found outside the country was detected in any samples tested. Reactivity of new CPV-2a and 2b variants against antibodies produced by the current vaccine products was determined by a cross hemagglutination-inhibition test. The recent field CPV isolates reacted more efficiently to the antibodies produced in dogs vaccinated with the new CPV-2b vaccine strain than the conventional CPV-2 vaccine strain.  相似文献   
53.
OBJECTIVE: To establish novel polymorphic markers for analysis of loss of heterozygosity (LOH), so as to study the possible involvement of BRCA2 in mammary tumors obtained from dogs. SAMPLE POPULATION: Blood samples, mammary gland specimens, or mammary tumors from 3 tumor-bearing dogs and 10 tumor-free dogs. PROCEDURES: Nucleotide sequence analysis was performed with a DNA autosequencer. Loss of heterozygosity analysis was performed for markers established in the present study. The expression level of canine BRCA2 was quantified by real-time PCR analysis. RESULTS: 3 novel microsatellite markers with high heterozygosity rates (> 50%) were established, and the previously reported marker for canine BRCA2 gene locus was improved. These markers were used for the analysis of DNA from formalin-fixed and paraffin-embedded samples. By use of these markers, LOH in canine BRCA2 was identified as a result of recombination. In mammary tumor DNA that corresponded to the LOH-positive dog, the level of canine BRCA2 expression was decreased compared with that of nonneoplastic mammary gland tissue; the open reading frame contained 4 missense variations, 1 insertion variation, and 1 silent variation, some of which were localized to functional domains. CONCLUSIONS AND CLINICAL RELEVANCE: 3 novel polymorphic markers were developed for LOH analysis of canine BRCA2 and identified a dog with LOH with some variations in the functional domains. These markers could be useful for assessing the relevance of BRCA2 variation in mammary tumors of dogs.  相似文献   
54.
The feces, colonic contents, and colonic mucosa from two beagles and a mongrel with and without mucohemorrhagic diarrhea were anaerobically cultured and after 72 hr, lucent and rough colonies with weak beta-hemolysis were observed. Small spirochetes with one or two loose waves in the colonies were observed under a phase contrast microscope and the spirochete cells sometimes aggregated. The 16SrDNA sequencing results demonstrated that the canine isolates were B. pilosicoli and the base alignments registered in DDBJ. This is the first report concerning the isolation of B. pilosicoli from dogs in Japan.  相似文献   
55.
Luteinizing hormone (LH)-stimulated steroidogenesis in luteal cells is known to be mediated through the activation of cyclic AMP (cAMP)-dependent protein kinase, and to be also modulated by calcium-dependent mechanisms. In the present study, we tested the hypothesis that LH stimulates progesterone (P4) production in bovine luteal cells through activation of phospholipase (PL) C by using a cell culture system. Bovine mid-luteal cells (Days 8-12 of the estrous cycle) were cultured for 24 h and then exposed to a PLC inhibitor (U-73122; 10 microM) with or without LH (10 ng/ml) for 4 h. U-73122 blocked LH-stimulated P4 production without affecting cAMP accumulation. Moreover, exposure of luteal cells to PLC increased P4 production in a dose-dependent manner. These results support the hypothesis that the luteotropic action of LH in bovine luteal cells is mediated not only by activation of adenylate cyclase but also by activation of PLC.  相似文献   
56.
To predict the long-term behavior of trace metals in a soilprofile, we studied the vertical distributions of barium, zinc,copper, chromium, nickel, cobalt, lead, and the principalmetals, aluminum, iron and manganese, in three soils withdeveloped horizons obtained from rural areas in Japan. Totalelement analysis and selective extraction tests with variousreagents were conducted to clarify the extractability of themetals at each sampling depth.Soil-b (Dystric Cambisols) had the highest extractability ofelements although the vertical distributions of its traceelements were similar to those of soil-d (Umbric Andosols),which had to lowest metal extractability of the three soils.Soil-KUR (Orthic Acrisols or Dystric Cambisols) was the oldest of the three soils and showed downward movement of some tracemetals (chromium and nickel) and principal elements (Fe and Mn)that was probably induced by long-term weathering.The extractability of manganese, zinc and barium with water washigher than other metals examined in all three soils. Lead andcobalt in soil-b and soil-KUR also were considered to have highextractability under long-term weathering processes. Zinc andlead accumulated near soil surface showed higher extractabilitywith every reagent used than those in deep layers of the three soils.  相似文献   
57.
Bacterial strains isolated from the rhizosphere of angelica trees were evaluated for their antagonistic activity against Phytophthora cactorum, a causal agent of Phytophthora root rot. Of these, three bacterial strains, designated as T-1-8, T-1-14 and T-1-23, strongly inhibited mycelial growth of P. cactorum ARE-862 in a dual-culture plate assay. Biocontrol activity of these strains was then examined by dipping root of young seedlings of angelica trees into a bacterial suspension. The incidence of Phytophthora root rot was markedly suppressed for at least 79 days in pot tests when treated seedlings were planted in naturally infested soil. The suppression was maintained through June of the next year. In addition, these strains significantly reduced the development of Phytophthora root rot up to 47 days in naturally infested field and up to 63 days (the last day of testing) in an artificially (moderately) infested field. Based on their main bacteriological properties, strain T-1-14 was identified as Enterobacter cloacae and T-1-8 and T-1-23 were identified as Serratia ficaria. Received 5 July 1999/ Accepted in revised form 25 October 1999  相似文献   
58.
59.
A 12‐year‐old spayed female Shiba Inu dog was referred to our hospital for a suspected mast cell tumor (MCT) of the bone marrow (BM). Laboratory abnormalities included severe nonregenerative anemia (packed cell volume or PCV: 12.5%; reference interval (RI): 37.3‐61.7%; reticulocytes: 35.1 × 103/µL; RI: 10‐110 × 103/µL), and a few mast cells were visualized in the blood smear examination. The BM was hypercellular with hematopoietic cells, a decreased myeloid:erythroid (M:E) ratio (0.77; RI, 0.9‐1.8), and no dysplastic hematopoietic cells. Mast cells accounted for 11.5% of the total nucleated BM cells. Neoplastic mast cells and histiocytes phagocytizing erythroid progenitor cells were occasionally noted. The dog was diagnosed with precursor‐targeted immune‐mediated anemia (PIMA) concurrent and a stage IV MCT infiltrating the BM. Multimodal treatment included toceranib, imatinib, vinblastine, lomustine (CCNU), prednisolone, cyclosporine, mycophenolate mofetil, and a blood transfusion. The dog died due to MCT progression lasting 139 days after the initial BM examination. To the best of our knowledge, this is the first report of a dog presenting with PIMA and a stage IV MCT infiltrating the BM.  相似文献   
60.
This report describes the cases of two Miniature Dachshunds who were suspected to have immune-mediated hemolytic anemia (IMHA) and were treated with immunosuppressive therapy. However, progression of anemia, increases in C-reactive protein (CRP) and total-bilirubin (T-Bil) levels, splenomegaly, transition to nonregenerative anemia, and thrombocytopenia occurred after the treatment. Splenectomy and bone-marrow aspirations were performed subsequently. Both dogs were diagnosed with hemophagocytic syndrome (HPS) associated with IMHA. Unfortunately, they died 9 and 6 days later. These findings indicate that some cases of refractory IMHA have the pathogenicity of HPS. HPS should be included as a differential diagnosis of refractory IMHA concurrent with thrombocytopenia. Continuously elevated CRP and T-Bil levels may be helpful indicators in the detection of HPS associated with IMHA.  相似文献   
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