Comparison of the effects of isotonic and hypertonic sodium bicarbonate solutions on acidemic calves experimentally induced by ammonium chloride administration

The objectives of this study were to evaluate and compare the effects of intravenously (IV) administered infusion of isotonic solution (ISB) or hypertonic sodium bicarbonate solution (HSB) on acid-base equilibrium and the plasma osmolarity in acidemic calves experimentally induced by 5 M-NH(4)Cl, IV infusion (1.0 ml/kg, over 1 hr). The ISB and HSB infusion induced progressive and significant increases in their HCO(3)(-) and BE levels that persisted throughout the period of fluid administration. The plasma osmolarity in the ISB groups was significantly decreased. The plasma osmolarity in the HSB group was significantly higher than in the calves in the other groups (p<0.05). ISB solution might be safe and effective for treating and reviving conscious calves from experimentally induced metabolic acidosis.     

Molecular characterization of Blastocystis isolates from primates

Twelve Blastocystis isolates from primates were analyzed genetically by polymerase chain reaction (PCR) using diagnostic primers and PCR-restriction fragment length polymorphism (RFLP) of SSUrDNA. Two distinct genotypes, subtype 1 and a variant of subtype 1, were detected in two and six of the 12 isolates, respectively. The RFLP profiles of the isolates designated as subtype 1 were identical to the profile of ribodeme 1. The RFLP profiles of the six isolates designated as variants of subtype 1 were different from the profile of the variant of subtype 1 from a human reported previously. The other four isolates were not amplified with any diagnostic primers, but three of them showed the same RFLP profiles as ribodeme 6. This study was the first genomic analysis of Blastocystis isolates from primates, and showed the genetic similarity between the isolates from primates and the genotypes of Blastocystis hominis. However, it was unclear whether the isolates examined were zoonotic or not. Therefore, it is necessary to reveal the phylogenetic relationships between the isolates from primates and the multiple genotypes of B. hominis.     

Experimental gizzard erosions in specific-pathogen-free chicks by serotype 1 group I avian adenoviruses from broilers

The pathogenicity of serotype 1 group I avian adenovirus (GIAAV) strains isolated from gizzard erosions for 1-wk-old specific-pathogen-free (SPF) chickens was investigated. In Experiment 1, SPF chickens inoculated orally with a serotype 1 strain (Tokushima2000/GE) of GIAAV isolated from gizzard erosion in broilers were euthanatized and necropsied from 3 to 12 days after inoculation. Clinically, there were no significant signs in the chickens inoculated with Tokushima strain. The gizzards were found macroscopically to be dilated with liquefied contents. The koilin layer of the gizzard exhibited multifocal white lesions with occasional erosions. Gross lesions of the koilin layer (white foci and erosion) appeared at 3 days after inoculation and persisted until 12 days after inoculation. The gross lesions were most severe at 9 days after inoculation. Histologically, multifocal degeneration, necrosis, and loss of the glandular epithelial cells with intranuclear inclusions, liquefactive change of koilin substance, and erosive lesions of koilin layers and surface epithelium of the gizzards were observed. Macrophages increased in the focal areas of the lamina propriabelow the liquefactive koilin substances. Immunohistochemically, intranudear inclusions were positive against GIAAV antigen. Histologic lesions of gizzards were most severe at 7 and 9 days after inoculation, but the frequency of intranuclear inclusions was greatest at 5 days after inoculation. In Experiment 2, the pathogenicities of four strains of serotype 1 GIAAV for 1-wk-old SPF chickens were compared. Three strains isolated from gizzard erosion had similar pathogenicities but one strain from a normal chicken was not pathogenic for chickens. These results suggest that gizzard erosions by serotype 1 GIAAV infection may occur in broiler chickens in Japan.     

Serum leptin levels during the periparturient period in cows

Serum leptin concentrations were measured in antenatal and postnatal cows housed at two different locations. The mean serum leptin concentration was 9.2 +/- 0.6 ng/m l (n=22) in one group, and was slightly lower in the other (7.4 +/- 0.4 ng/ml, n=54), probably because of the different nutritional conditions between the two groups. There was no consistent variation in relation to the menstrual cycle and the periparturient period in both groups. Moreover, serum leptin concentrations during the periparturient period were independent of the number of delivery and the incidence of mastitis and milk fever. These results are quite different from those in rodents and human, suggesting the different regulatory mechanism of circulating leptin concentration in cows.     

Phytotoxin produced by Streptomyces sp. causing potato russet scab in Japan

A phytotoxin isolated from the Stretomyces sp. causing potato russet scab in Japan (Kamenoko-byo in Japanese) was identified as a 16-membered macrolide, FD-891. It induced necrosis in potato tuber slices above 50 µg/disk, which is about 1/100 the activity of thaxtomin A. The phytotoxin was detected in potatoes infected by the pathogen and was produced by other pathogenic strains with different geographic origins.     

The possibility of factors other than phytoalexin accumulation preventing fungal growth in the incompatible interactions of soybean with Phytophthora megasperma f. sp. glycinea

Soybean ( Glycine max ) cv. Harosoy 63 is resistant to race 1 and susceptible to race 9 of Phytophthora megasperma f. sp. glycinea (Pmg). In detached primary leaves inoculated with zoospores, growth of race 1 was completely suppressed 16 h after inoculation, while race 9 was unaffected. The amount of the phytoalexin glyceollin that accumulated, however, was not significantly different in either the incompatible or compatible interaction 16 h after inoculation. At the circumference of the inoculated area, a slight accumulation of phytoalexin was observed only in the incompatible interaction 20 h or more after inoculation. Tolerance of race 9 to the phytoalexin was significantly higher than that of race 1 when the phytoalexin was added to agar. Moreover, race 9 degraded glyceollin faster than race 1. On leaves inoculated at separate points with either race, the lesion associated with race 9 never colonized areas inoculated with race 1. These results suggest that factor(s) other than the accumulation of phytoalexin in soybean tissue might cause cessation of growth of Pmg.     

Artificial insemination with canine spermatozoa frozen in a skim milk/glucose-based extender

Due to the recent outbreak of avian influenza, transportation of frozen canine semen with egg yolk has been sharply restricted. Thus, there is urgent need to develop a novel egg yolk-free extender for freezing canine spermatozoa. In the present study, the effect of using skim milk/glucose (SG)-based extender without egg yolk on the motility and fertilizing capacity of canine spermatozoa frozen-thawed in the presence of glycerol was examined. There was a tendency for the proportion of motile spermatozoa exposed to SG-based extender for 3 h to be higher than that exposed for 1 h, but the difference was not significant. The motility and other viability parameters of canine spermatozoa after thawing were similar to those obtained with an egg yolk-based extender. When spermatozoa frozen with SG-based extender containing glycerol after 3 h exposure were transcervically inseminated into 2 recipient bitches, a total of 6 pups were obtained. These results suggest that a simple extender composed of skim milk, glucose and glycerol is useful for cryopreservation of canine spermatozoa, which may contribute to improved exchange of genetic material and efficient production of companion and working dogs, such as guide dogs for the blind.     

Comparative hepatotoxicity of a herbicide,epyrifenacil, in humans and rodents by comparing the dynamics and kinetics of its causal metabolite

A new herbicide, epyrifenacil (S-3100), inhibits protoporphyrinogen oxidase (PPO) in plants. Repeated administration of epyrifenacil in laboratory animals led to some toxicological changes related to PPO inhibition, e.g., hepatotoxicity caused by porphyrin accumulation and anemia caused by the inhibition of heme biosynthesis. In vitro studies revealed that an ester-cleaved metabolite, S-3100-CA, is predominant in mammals, exhibits PPO-inhibitory activity, and thus is the cause of epyrifenacil-induced toxicity. To assess the human risk, the effects of species differences on the dynamics (PPO inhibition) and kinetics (liver uptake) of epyrifenacil were evaluated separately. The results of in vitro assays revealed an approximately tenfold weaker inhibition of PPO by S-3100-CA in humans than in rodents and six- to thirteen-fold less hepatic uptake of S-3100-CA in humans than in mice. Finally, it was suggested that humans are less sensitive to the toxicity of epyrifenacil than are rodents, although further mechanistic research is highly anticipated.     

Color development of proanthocyanidins in vanillin-hydrochloric acid reaction

The influence of proanthocyanidin (PA) structures contained in bark on color development in the vanillin-hydrochloric acid (V-HCl) method used widely as a quantitative method for measuring PA were examined. The maximal absorption wavelength was different in terms of the bark from which the PA was obtained. Phenyl nucleus (resorcinol, phloroglucinol) constituting the A-ring of PA reacts with vanillin to produce the color. The maximal absorption wavelengths of the solutions from synthesized procyanidin and profisetinidin were 500 and 540 nm, respectively, indicating that the color tone differs in the V-HCl method based on the hydroxylation patterns of the A-ring. The colored solution of (+)-catechin with vanillin was dialyzed, and the resulting product (C-VC) was analyzed by gel permeation chromatography and ¹H nuclear magnetic resonance. It was found that C-VC was a polymer complex consisting of 9mol (+)-catechin moieties and 10mol vanillin moieties. It was presumed that the cationized vanillin molecules that do not combine with (+)-catechin play an important role on color development in the presence of C-VC.This study was presented at the 44th and 45th Annual Meetings of The Japan Wood Research Society, Nara and Tokyo, April 1994 and April 1995     

用紫外线自动检测柑橘损伤果的研究

提出了检测柑橘损伤果的方法,通过分析选择了激起波长３５２ｎｍ,确定了ＣＣＤ摄像机用紫外线光源,叙述了各种条件和参数与荧光辉度差的关系,根据分析结果,设计了一套损伤果自动检测系统,该系统检测速度达到了５个／ｓ。