Search

A strain of S.cerevisiae, KL14-4A, was not affected evidently forthe growth on a complete glucose medium containing high concentration (10 mg/ml) of paromomycin. KL14-4A was crossed with a strain, C814-36B, that could not grow on the medium containing the same concentration of the drug. Examination of the zygore progeny indicated that somatic segregation had occurred for the characters of resistance and sensitivity to the drug. Assay of ascospores from the diploid clones of the two strains indicated that the genetic character as well as the mitochondrial paromomycm resistance, was irregularly segregated during meiosis. From the results it was assumed that KL14-4A might harbor non-mitochondrial cytoplasmic patomomycin-resistance gene(s), together with the mitochondrial paromomycinresistance gene, and both characters of paromomycin resistances might be controled by chromosomal gene(s).

The production of soybeans increases every year owing to the increase of demand for the domestic soybeans among the consumers in Japan and the rate of use of combine for harvesting soybeans increases because of a labor saving harvesting method. But, drying processing technique for the high moisture content soybeans harvested by combine has been retarded, and the degradation of soybeans and the heavy labor work in the process of drying become a problem. The efficient drying processing technique keeping the quality of soybeans harvested by combine, has been strongly required. In the drying processing of high moisture content soybeans, there occurs the risk of swelling in soybeans when the air ventilation in the layers is not sufficient. The activity of microorganism or mold increases when the temperature of the air exceeds 80% humidity and over 20℃temperature. It is necessary to adjust the temperature and humidity of the air ventilation to be out of this dangerous zone. In the meantime, it is necessary also to control the drying rate of soybeans so as to avoid the occurrence of the seed-coat cracking or the wrinkle of soybeans. To develop the effective artificial drying method keeping the quality of soybeans, the investigation on the physical properties of soybeans relating to the drying processing and the analysis of the drying process of soybeans are indispensable. However, the study has been retarded in comparison with the study of rice or wheat. In this study, the fundamental properties of soybeans relating to the drying and the characteristics of the pressure loss in driers such as flat be driers equipped with the bucket conveyer or dry stores were clarified and a drying simulation model for analyzing the process of drying was developed and investigated and the mechanism of the generation of coat cracking of soybeans and the effective treatment of the ventilation air to minimize the coat cracking were cleared. Through this study, the fundamental techniques for drying soybeans harvested by combine were developed. In the first chapter, the significance and objectives of this study were described based on an outline of soybean production and studies on soybean drying... In the second chapter, the dependence of physical properties as specific volume, bulk volume, rate of volume on moisture content of soybeans (tachinagaha, tamahomare, fukuyutaka, suzuyutaka, enrei variety) was theoretically considered and determined as follows with principal properties of specific volume of drymatter V,_0, coefficient of rate of volume k of average soybeans. V_m=V_0+γ・m=0.771+0.965m (0.1m+V_0^2)_(0m^3/kg), V_m^1 ; specific bulk volume, 1-ε ; rate of kernel volume, V_0=0.771(10^m^3/kg), V_=0.7460 Hence, physical properties of soybean for a drying simulation model were shown with principal parameters of V_0, V_, k. In the third chapter, the pressure loss of soybeans was examined and the data was analyzed using the non-dimensioned Navier-Stokes equations for forced air in accumulations. And resistance factors or friction factors of soybeans were expressed as the function of Reynolds number, to esteem a pressure loss in air forced layers of soybeans by calculation. We could get an experimental equation of resistance factor that was applied for generally to pressure loss of soybeans, in 40

Lateral buckling is one of the most important limit states for glue-laminated wood beams with deep depth and long span. The purpose of this paper is to present design formulae for lateral buckling strengths of glue-laminated wood beams. Lateral buckling tests for three sectional types of laminated wood beams are conducted. Based on the test results, it is shown that the lateral buckling strengths agree well with the strengths based on the classical elastic theory for beams. The variations of the lateral buckling strengths are presented based on the first-order second-moment method for the calculation of resistance factors of partial safety factor formats.

Trends of heart rate increase just after the stepwise application of physical stress seem to suggest that two factors model, time dependent like inductance and time independent like resistance factors, may be useful. It is expected that a time constant (TC) of the system would indicate an individual capacity of man to some extent. This report is to show the results or longitudinal study on the behavior of TC values in one male subject, age 33. An electronically controlled bicycle ergometor (ISOPOWER, TAKEI) allowes to apply rectangular type stress of various intensities (from 60W to 130 W, rate of rise 20W per sec.). A change of heart rate is monitored by a photoelectric sencer. Fig.1 shows analog recordings. TC was calculated from digital readings without waiting heart rate to reach its new steady level. Our tentative conclusion is as follows ; (1) TC values at medium intensities (90, IIO W) are most sensitive to a level of physical fittness. Sedentary life style elongates TC value. (2) TC values at lower intensities are more closely related to "liveliness" rather than to the capacity of physical fittness.

This review shows a summary of our previous studies concerning how to augment alveolar bone ridge by minimum intervention using autologous alveolar bone derived mesenchymal stem cells (MSC) and scaffolds. We successfully collected MSC from alveolar bone marrow using newly developed puncture needle, and expanded them in vitro. We have developed serum free culture medium and found several new initial osteogenic markers and new resistance factors for external stimuli on MSC. Furthermore, we found several factor controlling MSC migration and osteogenic differentiation. We combined MSC with calcium phosphate scaffold and transplanted them into canine edentulous model and successfully observed osseointegration between augmented bone and implant. We are going to start alveolar bone augmentation treatment using alveolar bone marrow MSC/scaffold utilizing above mentioned techniques in the near future.

抗生物質や抗菌性薬剤は，獣医領域において家畜の疾病予防および治療をはじめ，発育促進や飼料効率の改善などきわめて広範囲かつ大量に使用され，家畜の生産性の向上に大きく貢献している。しかしながら一方，このような大量使用により薬剤耐性菌の出現や伝達性薬剤耐性因子(Rプラスミッド)保有菌の増加などが，家畜衛生上および公衆衛生上重要な問題として提起されるようになった。 さて，家畜の慢性呼吸器病の病原体として重視されているマイコプラズマに対しては，マクロライド系やテトラサイクリン系抗生物質あるいはニトロフラン剤などの合成抗菌剤などが使用されてきたが，近年これら薬剤に対して耐性を示すマイコプラズマの出現が他の病原細菌と同様に明らかにされ，この対策が強く望まれている。 そこで，新しい型の抗マイコプラズマ剤を見出すため，1970年より土壌微生物の培養生産物や種々の合成化合物などについて評価試験を実施した。その結果，Thiosemicarbazone類(TS)に極めて強い抗マイコプラズマ活性のあることを究明した。このTSは，Amidinohydrazone類(AH)と化学構造的に類似し，AHのアミジノ部位をイオウ(S)に置換されたものである。しかし，これら両系統の化合物の性状の差は，AHが一般に塩酸塩として合成され水溶性であるのに対し，TSは水に難溶性である。 これまでに，TSおよびAHの生物学的活性，特に抗菌活性，抗原虫活性および抗ウィルス活性については明らかにされているものの抗マイコプラズマ活性については明らかでなかった。そこで，TSおよびAH化合物114種について抗マイコプラズマ活性を試験し，これら化合物の構造と活性との関係について追究した。 さらに，試験管内で有効性が明らかにされた化合物について，動物生体に投 与した時の薬物の動態，特に血中濃度を指標にした腸管吸収性とニワトリの呼吸器性マイコプラズマ症およびマウスのマイコプラズマ性肺炎の人工感染モデルにおける生体内での有効性について追究し新たな知見を得た。 その概要を述べれば以下のとおりである。1.供試化合物の抗マイコプラズマ活性について 供試化合物114種（TS39化合物，AH75化合物)について，Mycoplasma gallisepticum 4株に対する最小阻止濃度(MIC)を液体培地希釈法により測定し，各供試化合物の抗マイコプラズマ活性を比較検討した。(1) 供試化合物の中で，α-Ketoaldehyde bis-TSは、極めて強い抗マイコプラズマ活性を示した。特に、Methylglyoxal bis-TSのMICは0.0039～0.0078μg/mlで一連の供試化合物の中で最強の活性を示した。次いで，Phenylglyoxal体、Hydroxymethylglyoxal体，Hydroxyphenylglyoxal体の順であった。これらはいずれも0.1μg/ml以下のMICであり，マクロライド感受性および耐性マイコプラズマの両者に対して同等な活性を示した。(2) Methylglyoxal bis-TS化合物の4位の置換基では，メチル基およびエチル基が最も強い活性を有し，ハイドロキシメチル基，ブチル基，フェニル基の順に活性が低下することを明らかにした。(3) TSの抗マイコプラズマ活性発現において，その分子中の>C=CC=CC=C, Antibiotics and antibacterial drugs have been used extensively in veterinary medicine and livestock breeding for both therapeutic and prophylactic purposes and also for the promotion of growth and for the improvement of feed efficiency. In consequence, the occurrence of drug-resistant bacteria and transferable drug-resistance factors (R plasmids) has been wide, and has brought about serious problems in the field of both animal and public health. At present, effective chemotherapeutics against Mycoplasma include antibiotics of the tetracyclines and macrolides groups and synthetics antibacterial agents as nitrofurans. It has been clarified, however, that some Mycoplasma strains, as well as some bacterial strains, have been proved to be resistant to those drugs. Then, to find new and effective antimycoplasmal substance, since 1970, the author has examined the antimycoplasmal activity of many fermentative samples of soil microorganisms and various synthetic chemical preparations. It was found, as described in this thesis, that two novel thiosemicarbazone (TS) compounds had a very strong antimycoplasmal activity in vitro. The chemical structure of these TS compounds are similar to that of amidinohydrazone (AH) compounds which also have antimycoplasmal activity to some extent. Namely, their imino groups in the amidino moiety are substituted by sulfur atoms. AH and TS are different in their simple physicochemical properties. For example, All is generally water soluble and prepared as hydrochloride, while TS is hardly soluble in water. The biological activities, especially antibacterial, antiprotozoal and antiviral activities, of AH and TS have been clarified up to this time. Nothing has been known, however, about the antimycoplasmal activity of AH and TS. In this study, a total of 114 chemical compounds of AH and TS were examined for antimycoplasmal activity in vitro. These compounds which were found to have antimycoplasmal activity in vitro, were further examined for the absorption in the intestinal tract of mice and pigs. Moreover, two TS compounds were examined for the antimycoplasmal efficacy in vivo by using chickens with experimental respiratory mycoplasmosis and mice with mycoplasmal pneumonia. The results of this study are summarized as follows.1. In vitro antimycoplasmal activities of the test compounds. A total of 114 test compounds (75 AH and 39 TS compounds) were subjected to the estimation of the minimum inhibitory concentration (MIC) against four strains, S-6, KP-13, CH-3T and 4AS, of Mycoplasma gallisepticum by using the liquid medium dilution method. The antimycoplasmal activities estimated were compared with one another. 1) In AH compounds, including benzalacetone, acetophenone and benzaldehyde, the p-nitro and p-chlor forms of benzalacetone compounds have comparatively stronger antimycoplasmal activity. The MIC's of the derivatives were 3.12 ～ 6.25 μg/ml. As for the substitution of the benzene position, the para position exhibited stronger antimycoplasmal activity than the meta or the ortho position. 2) It was evident that the > C = C < structure of AH played an important role in the activity of AH against Mycoplasma. This role was as important as the function of this structure against bacteria or fungi. 3) AH possessing an alkoxy group had stronger activity than AH compounds lacking this group. It was speculated that the introduction of an alkoxy group to the AH derivative might increase its transferable properties through the cell membrane of the Mycoplasma organisms. 4) It was shown that bis-AH had little activity against Mycoplasma. Then, the substitution of amidino moiety did not greatly increase its antimycoplasmal activity. 5) The TS derivatives of benzalacetone, acetophenone and benzaldehyde had weaker activities against Mycoplasma than the similar derivatives of AH. The antimycoplasmal activity of TS might also be closely related to their > C = C < structures and the alkoxy radical. 6) Alpha-ketoaldehyde bis-TS derivatives, unlike AH, had very strong efficacy against Mycoplasma. Methylglyoxal bis-TS derivatives in them had the strongest and most striking efficacy against Mycoplasma. In a series of synthetic preparation of this study, their MIC's were 0.0039 ～ 0.0078 μg/ml. The antimycoplasmal activity decreased in methylglyoxal, phenylglyoxal, hydroxymethylglyoxal and hydroxyphenylglyoxal compounds, in the order listed, in the α-ketoaldehyde bis-TS derivatives. Their MIC's, however, were less than 0.1 μg/ml. Furthermore, these derivatives showed strong activity against Mycoplasma strains sensitive or resistant to the macrolide antibiotics. It was demonstrated that the introduction of a methyl or an ethyl on the 4-position of the methylglyoxal bis-TS produced the strongest and most striking efficacy against Mycoplasma.2. The absorption of antimycoplasmal compounds through the intestinal tract. Eight synthetic compounds belonging to the α-ketoaldehyde bis-TS group were selected for these studies. These compounds all exhibited fairly strong antimycoplasmal activity in vitro. The absorption of these compounds through the intestinal tract of mice and pigs was estimated and compared with one another. 1) It was observed that two of eight compounds were effectively absorbed into the blood. The two compounds were methylglyoxal bis (4-methyl-TS) and methylglyoxal bis(4-ethyl-TS). It was presumed that the chemical structure, the molecular weights and the method of bio-assay were possible reasons for the lack of absorption through the intestinal tract in mice and pigs. 2) It was demonstrated that the concentration of methylglyoxal bis (4-methyl-TS) and methylglyoxal bis (4-ethyl-TS) in the blood could be expressed by means of a mathematical formula. When these test compounds were administered orally to pigs at the dose of 100 mg per kilogram of body weight, it was estimated that a rise and fall in the blood concentration of these test compounds were expressed as the following general formulae. methylglyoxal bis(4-methyl-TS): Ct=7.986e^-0.053t -7.995e^-0.117t methylglyoxal bis(4-ethyl-TS): Ct=82.60e^-0.097t -117.55e^-0.151t +35.19e^-0.295tThese formulae were used to calculate the times required for methylglyoxal bis (4-methyl-TS) and methylglyoxal bis (4-ethyl-TS) to reach the highest concentration in the blood after oral administration. The times required of the two compounds were 12.4 and 13.0 hours, respectively, and the highest blood concentrations at those times were 2.27 and 7.66 μg/ml, respectively. It was estimated that the biological half-life periods of the compounds in vivo were 13.1 and 8.3 hours, respectively, in oral administration. 3) With the administration in the form of feed additives, methylglyoxal bis (4-methyl-TS) showed a higher level and a longer lasting characteristic in the blood than methylglyoxal bis(4-ethyl-TS).3. The efficacy of antimycoplasmal compounds on the experimental mycoplasmal infection. Methylglyoxal bis (4-methyl-TS) and methylglyoxal bis(4-ethyl-TS) which possessed stronger antimycoplasmal activity in vitro and proficiency in passing through the intestinal tract of mice and pigs, were examined for their efficacies against respiratory mycoplasmosis of chickens and mycoplasmal pneumonia of mice. 1) Methylglyoxal bis (4-methyl-TS) was very effective in preventing gross air-sac lesions when it was administered to chickens with respiratory mycoplasmosis at the level of five grams per ton of feed. This level, however, could not elicit the decrease in number or the disappearance of Mycoplasma organisms from the respiratory organs. The administration of a level of twenty-five grams of the compound per ton of feed decreased in number of Mycoplasma organisms in these organs of infected chickens. 2) It also was evident that methylglyoxal bis (4-methyl-TS) and methylglyoxal bis (4-ethyl-TS) prevented experimental mice significantly from manifesting any clinical symptoms of mycoplasmal pneumonia. From these results, the two synthetic compounds appear to be worthy of further study as to their possible efficacies against other animal mycoplasmal infections. In conclusion, the eight compounds belonging to the α-ketoaldehyde bis-TS of 114 compounds exhibited fairly strong antimycoplasmal activity. Of them, two compounds of methylglyoxal bis-TS were effectively absorbed into the blood through the intestinal tract in mice and pigs. A series of studies were carried out to clarify the relationship between the structure of each α-ketoaldehyde bis-TS and its activity or its absorption from the intestinal tract. These two compounds were demonstrated to have an effect to inhibit clinical symptoms in experimental respiratory mycoplasmosis of chickens and mycoplasmal pneumonia of mice. From these results, it was concluded that the two compounds, methylglyoxal bis (4-methyl-TS) and methylglyoxal bis (4-ethyl-TS), were new type antimycoplasmal substances. The results obtained are believed to serve as basic data for further studies on the development of antimycoplasmal and other chemotherapeutic agents.