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21.
Complement-mediated cytotoxicity for porcine islet cells (PICs) was evaluated using sera of six animal species. Then soluble complement receptor type-1 (sCR1) as an anti-complement agent was added to those sera, and the changes in 50% hemolytic unit of complement serum (CH50) and cytotoxic effect of those sera on PICs were examined. All the sera except for that of pig showed cytotoxicity. However, the extent of toxicity was considerably different between species. In the rat and human serum, sCR1 significantly reduced CH50 and cytotoxicity, however in the dog serum, sCR1 had no suppressive effects. These results may suggest that complement contribute to humoral cytotoxicity for PICs as a main factor, and the compatibility of complement with PICs differs between animal species.  相似文献   
22.
23.
The flagellins purified from Pseudomonas syringae pv. tabaci induce a hypersensitive reaction in nonhost tomato cells. To investigate the role of flagella and flagellin in the compatible interaction, we generated two types of flagella-defective mutant. The fliC mutant lost the fliC gene that encodes flagellin protein, whereas the fliD mutant lost the fliD gene that encodes HAP2-capping protein. The two mutants had markedly reduced ability to cause disease symptoms in tobacco leaves. Furthermore, propagation of the mutants in tobacco leaves was less than that in wild-type pv. tabaci. Compared to the inoculation with wild-type pv. tabaci, inoculation with the two mutants did not markedly induce the expression of typical defense response-related genes such as PAL and hsr203J. Complementation of each fliC and fliD gene to the corresponding deficient mutant restored motility and virulence. These results indicate that flagella of P. syringae pv. tabaci are indispensable organelles for complete virulence on host tobacco plants.  相似文献   
24.
Nineteen analogues were synthesized by modifying the tert-butylhydrazine moieties of N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-2,3-dihydro-1,4-benzodioxine-6-carbohydrazide and N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methylchromane-6-carbohydrazide (chromafenozide), and the synthesized analogues were evaluated for their insecticidal activity against Spodoptera litura F. While all of the synthesized analogues had insecticidal activity inferior to those of the lead compounds, several of the analogues nonetheless showed high insecticidal activity. Chromafenozide has shown very high selectivity toward lepidopteran species.  相似文献   
25.
An automatic counting method was developed for fish blood cells using a fluorescent dye, 3, 3-dihexyloxacarbocyanine (DiOC (6)(3)), that selectively stain lipid bilayers in living cells. In the present study, the DiOC(6)(3) method was applied to quail (Cotumix cotumix japonica) blood cells. After quail blood cells were stained with DiOC(6)(3), absolute counts and relative proportions of erythrocytes, granulocytes, monocytes, and lymphocytes plus thrombocytes in whole blood were obtained by means of flow cytometry (FC). The number of each cell types by the FC was in good agreement with those counted microscopically. This method will offer new possibilities for routine blood cell counting for avian medicine.  相似文献   
26.
The effect of 1.35% isotonic sodium bicarbonate solution (ISB) administered intravenously on acid-base equilibrium was examined in 18 acidemic Japanese black beef calves with spontaneous diarrhea. The infusion volumes of ISB were decided based on the first half volumes of base needed. In 72.2% (13/18) of calves, improvement of acidemia was detected. There was good correlation (r=0.693, p<0.01) between infused volume of ISB and changes in base excess (y=1.097x + 4.762). Infusion volumes of ISB were 7.5, 10.2, 12.9 and 15.7 ml/kg, respectively, enough to correcting the first half of 5, 10, 15 and 20 mEq/l of base deficit in acidemic calves. Our finding suggested that ISB could be used to correct metabolic acidosis without altering electrolyte concentrations in calves.  相似文献   
27.
We investigated the physicochemical properties of the thermal gel of water‐washed pork meat (WWM) in the presence of the soluble fraction of porcine sarcoplasmic protein (SP) obtained with ammonium sulfate at 75 percent saturation. Two precipitated fractions of SP were obtained at 0–50 percent and 50–75 percent saturation, named SP‐f1 and SP‐f2, respectively, and the soluble fraction obtained at 75 percent saturation, SP‐f3, was used. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis showed that SP‐f3 contained mainly glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), while SP‐f1 and SP‐f2 had other SPs such as phosphorylase b, enolase, actin and phosphoglycerate mutase. The gel strength of WWM was greater when SP‐f3 rather than one of various animal proteins such as bovine plasma (BP), egg white, or whey protein isolates (WPI), was added and SP‐f3 had a gel‐enhancing effect as good as that of polyphosphate (PP). The gel strength of WWM with added SP‐f3 increased significantly with NaCl at 0.15 mol/L or more, but not in the absence of NaCl (0 mol/L). The effect of SP‐f3 was evident at neutral pH and maximum gel strength was obtained at a pH above 6.0. Differential scanning calorimetric (DSC) analysis showed that an endothermic peak corresponding to myosin heads in WWM shifted to a lower temperature with the addition of SP‐f3, as in the case of PP, though there was no such shift in the presence of other animal proteins (BP, egg white and WPI), suggesting that SP‐f3 increases the gel strength of WWM through the dissociation of actomyosin similar to PP. Scanning electron microscopy (SEM) revealed wall‐like structures among the protein strands in the WWM gel matrix in the presence of SP‐f3. The results of DSC and SEM indicated that the formation of a gel network in meat products is reinforced with GAPDH in SP after the interaction between GAPDH and myofibrillar protein.  相似文献   
28.
We investigated the optimal timing of simeconazole (RS-2-(4-fluorophenyl)-1-(1H-1,2,4-triazol-1-yl)-3-trimethylsilylpropan-2-ol) application for controlling rice kernel smut in field trials in Miyagi Prefecture, Japan, using formulations of simeconazole (1.5% granules). The field tests revealed that a submerged application of simeconazole granules (450–600 g ai/ha) at 1–5 weeks before heading was highly effective against kernel smut, with treatments 1–2 weeks before heading being the most effective. Submerged application of the fungicide at 2–5 weeks before heading was also highly effective against false smut, with treatment 3 weeks before heading being the most effective. These periods overlap the timing for optimal application of simeconazole to control rice sheath blight and ear blight. Consequently, we concluded that treatment with simeconazole 2–3 weeks before heading can be a useful tool for controlling all four diseases.  相似文献   
29.
We previously reported that the release of O2 from isolated pea cell walls was enhanced by a 70-kDa glycoprotein elicitor but was suppressed by mucin-type glycopeptide suppressors (supprescins A and B) prepared from pycnospore germination fluid of Mycosphaerella pinodes, causal agent of Mycosphaerella blight of pea. Here, we show that superoxide dismutase (SOD) in the apoplast fluid/cell wall of pea seedlings responds to the fungal elicitor and suppressor molecules. In a pharmacological study and with internal amino acid sequencing, the apoplastic SOD in a pea cultivar Midoriusui was found to be a Cu/Zn type SOD. We cloned a full-length cDNA of the Cu/Zn-SOD and designated it as PsCu/Zn-SOD1. An increase in PsCu/Zn-SOD1 mRNA and the PsCu/Zn-SOD1 protein was induced by treatment with the elicitor more intensively than by wounding. Such induction by the elicitor or wounding, however, was inhibited by the concomitant presence of supprescins. The SOD activity of recombinant PsCu/Zn-SOD1 was regulated directly by these signal molecules in a manner similar to their effect on the SOD activity in the apoplastic fluid and in the cell wall-bound proteins. Based on these findings, we discuss a role for PsCu/Zn-SOD1 in the pea defense response. The nucleotide sequence data of PsCu/Zn-SOD1 reported are available in the DDBJ/EMBL/GenBank databases under accession number AB189165.  相似文献   
30.
Inter-section hybrids were obtained in the reciprocal crosses between Primula filchnerae (2n = 2x = 24) of Sect. Pinnatae and P. sinensis ‘Fanfare’ (2n = 2x = 24) of Sect. Auganthus by rescuing ovules on half-strength (1/2) Murashige and Skoog's (MS) medium supplemented with 50 g l−1 sucrose, 2.5 g l−1 gellan gum, 0.1 mg l−1 α-naphthaleneacetic acid (NAA), 0.1 mg l−1 6-benzyladenine (BA) and 50 mg l−1 gibberellic acid (GA3). In ovule culture, germination occurred with radicle elongation but no plumule was observed. The radicle kept on the initial medium showed root proliferation with callus formation. When the calluses were transferred to (1/2)MS media containing 30 g l−1 sucrose and 3 g l−1 gellan gum, without plant growth regulators (PGRs) or with 1 mg l−1 zeatin and 0.1 mg l−1 NAA, plantlets were regenerated. The plants thus obtained were confirmed to be hybrids through flow cytometry (FCM) and random amplified polymorphic DNA (RAPD) analyses. The hybrid obtained when P. filchnerae was used as the maternal parent was diploid, whereas hexaploid hybrid was obtained when using P. sinensis as the maternal parent. The hexaploid hybrid might be produced through chromosome doubling of a triploid originated from the fertilization of P. sinensis with unreduced pollen of P. filchnerae.  相似文献   
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