The effect of sodium polyacrylate (PANa) on the aggregation and sedimentation state of pyrimidine penicillin G () was examined by the measurement of the apparent degree of aggregation (γ_m/γ₀), amount of adsorption (X), ζ-potential, porosity (ε), and tortuosity (q) of the sedimentation layer. of various primary particle radius (γ₀) and PANa of various molecular weight (Mη) were used as the sample. It was found that the adsorption isotherms of PANa on were of Langmuir type. Amount of saturated adsorption (X_∞ : mg/g) increased with the increase of Mη and the decrease of γ₀. A little increase of X_∞ was found in the presence of NaCl. X_∞ in mg/cm² showed a little higher value with the decrease of γ₀. η-Potential increased with the increase of PANa concentration and decreased in the presence of NaCl. forms secondary particles in water by aggregation and its γ_m/γ₀ and ε increased with the increase of PANa concentration and Mη. This tendency was more pronounced in the case of larger γ₀. The aggregation effect of PANa on decreased in the presence of NaCl. q decreased and q_v/q_H increased with the increase of PANa concentration. It was concluded that the anisotropy of the sedimentation layer increased by the nonspherical nature of the aggregated secondary particle grown up by PANa.

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Ninety strains of Clostridium butyricum/Clostridium beijerinckii group were used in order to find out phenotypic characteristics distinguishing C. butyricum from C. beijerinckii. “C. butyricum” strains can be differentiated from C. beijerinckii strains by the ability to grow in 20% bile, to produce lactic acid from broth and to ferment ribose, and the failure to produce butanol from broth and ferment inositol, melezitose and sorbitol.

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Nine strains of obligately psychrophilic bacteria, which were isolated from regions near Showa Station in Antarctica, were studied taxonomically. These strains were identified as Curtobacterium psychrophilum sp. n. (1 strain), Cytophaga antarctica sp. n. (3 strains), Cytophaga xantha sp. n. (1 strain), Spirillum pleomorphum sp. n. (2 strains), Micrococcus cryophilus McLean, Sulzbacker and Mudd, and Pseudomonas putrefaciens (Derby and Hammer) Long and Hammer (1 strain).

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The inhibition of mycelial growth of Lagenidium giganteum by neem oil was lower than that of Metarhizium anisopliae in

and Emerson's YpSs agar media. However, neem oil did not inhibit the mycelial growth of L. giganteum in sunflower seed extract agar medium, but did it inhibit the mycelial growth of M. anisopliae. The minimum inhibitory concentration of neem oil for L. giganteum was higher than that for M. anisopliae. The minimum fungicidal concentration of neem oil in medium was lower than in YpSs for both fungi. The spores of L. giganteum grown in SFE medium could be used with neem oil for vector control.

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The effect of primary particle radius (γ₀), addition of a polymer [po1y (vinylpyrrolidone), sodium carloxymethyl cellulose)], and centrifugal sedimentation on the sedimentation states of pyrimidine-penicillin G () were examined by the measurement of apparent aggregation degree (γ_m/γ₀, where γ_m is the apparent secondary particle radius), porosity (ε) and tortuosity (q) of the sedimentation bed, and the amount of polymers adsorbed on particles. The following results were obtained. 1) γ_m/γ₀ and ε did not change in parallel with each other while q and ε changed in the opposite direction with respect to the polymer concentration. 2) The effect of polymers on ε and difference in q with the direction of measurement were not found in the case of centrifugal sedimentation. 3) Saturated amount of adsorption X_∞ of the polymers was higher than the theoretical value which was calculated by assuming monlayer adsorption of the monomers. 4) Plots of the data to see the relation between q and (1-ε) gave straight line. 5) q_v/q_H decreased with increase in ε at γ₀= 1.8, 8.9, and 13.2 μmz, and almost constant against ε at 2.9 and 4.8 μm.

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Two kinds of fungal glucan, particulate yeast glucan () and lentinan, were examined for their immunopotentiating effect illustrated by reduced frequency of post-chemotherapy relapse in experimental mouse tuberculosis. Infected mice were treated by intensive chemotherapy with a three-drug combination [Streptomycin (SM) + isoniazid (INH) + rifampicin (RFP), ethambutol (EB) +INH+RFP, or SM+INH+pyrazinamide (PZA) ] for 5 months. After termination of chemotherapy, the mice of each treated group were divided into three subgroups to receive or not to receive glucan for 4 weeks and again for 4 weeks after a month interval. During this 3-month period and the succeeding 5 months, the mice were subjected to occasional sacrifice to examine the growth of latent tubercle bacilli in the lung and spleen by cultivation of tissue homogenates. The results indicated that the regimens with SM+INH+RFP and EB+INH+RFP were highly effective in eliminating persistent tubercle bacilli down to undetectable levels. However, later multiplication of the latent bacilli was observed during the advanced postchemotherapy period. The application of was most effective in prevention of this type of relapse in the spleen, but not so in the lung. Lentinan effect was manifested in the lung, but not in the spleen.

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Aculeacin A was lethal for proliferating cultures of C. albicans. However, there was a paradoxical relationship between the drug concentration and the fungicidal activity; the lethal effect was the greatest at levels of 0.08 to 1.25μg/ml and increases in the drug concentration above this range reduced its lethal effect. A similar anomalous dose-response patterns were also observed for the inhibitory effect of the drug on several cellular and subcellular biochemical activities. Association of this lethal effect of the drug was the formation of visible cell aggregates and the development of extremely huge forms in treated cultures. Aculeacin A induced osmotically fragile cells and viability of treated cultures was markedly reversed under high osmolarity. Tracer experiments and chemical analysis revealed that synthesis of alkali-insoluble glucan was inhibited by the drug to a greater extent than synthesis of mannan and any other species of macromolecules, with resultant formation of alkali-insoluble glucan-deficient cells. Aculeacin A inhibited synthesis of β-glucan from UDP-glucose catalyzed by cell-free extracts from C. albicans and S. cerevisiae. These data are consistent with the view that one of the principal target of aculeacin A action is on the, β-1, 3-glucan synthetase reaction.

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Lactobacillus kefiranofaciens is known to produce an exopolysaccharide (kefiran) that is either excreted in the growth medium or attaches to the cell wall. In order to achieve high exopolysaccharide production, we devel oped a new rice hydrolyzate (RH) medium using rice starch hydrolyzate as the carbon source and rice protein hydrolyzate as the peptone source. In this study, three fermentation experiments using RH medium, 10 medium and PYL10 medium were carried out, respectively. The highest amount of exopolysaccharide production was obtained from the culture grown in RH medium. Among the three various media compositions compared, rice protein hydrolyzate in the RH medium demonstrated the ability to significantly enhance exopolysaccharide production by L. kefiranofaciens. In addition, the cultivation of L. kefiranofaciens in a 500l tank was also experimentally conducted, and the maximum yield of exopolysaccharide from the RH culture was 2.5 g/l after a seven-day culture period at pH 5.0 and 33°C. This result indicates that it is possible to produce exopolysaccharide (OSKC) at the level required for large-scale industrial production through the cultivation of L. kefiranofaciens in RH medium.

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無症状(検診)グループと有症状(患者)グループの生存率を比較することにより, マンモグラフィによる乳房集団検診の利益/損失計算をおこなった.集団検診の経験が3年と浅いため, 病院患者グループの生存率(約3000症例)を用いて計算をおこなった.すなわち, 検診グループ罹患者の乳癌を患者グループ乳癌のうち病理学的早期乳癌の範疇とし, 両者の生存曲線の面積差から, persons-year gainとpersons-year lostの比を求めた.この値に実際の検診で得られたファクターを乗じて利益/損失比を求めた.集団検診の質を病院検査の質と同等に保ち, しかも無症状の婦人のみを対象とした結果, 触知不能癌の発見率は患者グループの15倍であった.僅か824例の中から7例の乳癌が発見され(0.85%), この発見率は従来我が国で定説となっている値の10倍であった.何才からマンモグラフィによる集団検診をおこなうべきかは常に論議のまとである.我々の集団検診の成績では, 30才から検診を始めても, 3段階の損失評価の何れにおいても, 利益が損失を遥かに上回る結果となった.断定的な結論を得るには, 年齢別の乳癌発見率が定常値となるだけの検診数が必要であり, さらに研究を重る予定である.

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Developing an adaptive 3-dimensional (3D) topology control algorithm is important because most wireless nodes are mobile and deployed in buildings. Moreover, in buildings, wireless link qualities and topologies change frequently due to various objects and the interference from other wireless devices. Previous topology control algorithms can suffer significant performance degradation because they only use the Euclidean distance for the topology construction. In this paper, we propose a novel adaptive 3D topology control algorithm for wireless ad-hoc sensor networks, especially in indoor environments. The proposed algorithm adjusts the minimum transmit power adaptively with considering the interference effect. To construct the local topology, each node divides the 3D space, a sphere centered at itself, into k equal cones by using Platonic solid (i.e., regular k-hedron) and selects the neighbor that requires the lowest transmit power in each cone. Since the minimum transmit power values depend on the effect of interferences, the proposed algorithm can adjust topology adaptively and preserve the network connectivity reliably. To evaluate the performance of algorithms, we conduct various experiments with simulator and real wireless platforms. The experimental results show that the proposed algorithm is superior to the previous algorithms in terms of the packet delivery ratio and the energy consumption with relatively low complexity.

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DNA polymerase η (hPolη) is a key protein in translesion DNA synthesis (TLS) in human cells. Its primary function is the error free replication through UV-induced TT cyclobutane dimers which present a barrier to DNA synthesis by other eukaryotic replicative polymerases. hPolη defects underlie the genetic disease xeroderma pigmentosum variant (XPV) characterized by higher susceptibility to UV-light induced skin cancers due to erroneous replication of the UV adducts. However, hPolη is also a very low fidelity enzyme when copying undamaged DNA or DNA with other adducts and is actively recruited during the somatic hypermutation of the immunoglobulin genes. Here, we demonstrate that hPolη restores partially the mutability and completely the survival of a UV non-mutable umuDC-deletion mutant of Escherichia coli after UVB irradiation. We chose UVB instead of UVC as a radiation source because UVB is a major cause of human skin cancer induced by sunlight. The umuDC genes encode endogenous TLS DNA polymerase V. The catalytic core lacking the C-terminal part of hPolη was even more biologically active than the full size protein and its activity was further enhanced by attaching the prokaryotic β-subunit binding motif to it. The mutagenicity and survival effects were enhanced upon the induction of hPolη expression and its catalytically inactive variant was unable to promote any mutagenesis. This suggests that hPolη directly participates in the replication of damaged DNA in the prokaryotic bacteria. To demonstrate that our system can be useful in studying different variants of hPolη in vivo we have constructed 4 amino acid substitution mutants with altered geometry of the catalytic site analyzed previously biochemically and confirmed their altered abilities to promote mutagenesis and survival after UVB irradiation. This study paves a way to generate a variety of useful derivatives of hPolη in prokaryotic systems.

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Tortuosity and viscosity of aqueous suspension of coarse particles under stirring were studied. Porosity, ε, was adjusted by changing the particle concentration tortuosity, q, was measured by the conductirity method, viscosity by a rotation viscometer, and apparent aggregation degree (γ_m/γ_o) by the sedimentation method. Pyrimidine-penicillin G () (primary particle radius γ_o, 1.8 and 13.2 μ), Nylon spheres (γ_o, 2.9 and 38 μ), glass spheres (γ_o, 45 and 100 μ), glass bars, and salicylic acid of various sizes (radius/length) were used as the suspending particles. Sodium dodecyl sulfate, and polyvinyl-pyrrolidone were used as the suspending agent. Horizontal tortuosity, qH, was independent of the stirring speed when the latter was over 2000 rpm in the case of glass bars (100 μm), while the qH value was constant in the entire range of the stirring speed in the case of (1.8 μ). Vertical tortuosity, q, was constant against all the stirring speeds tested. It was not affected by the viscosity and temperature of the suspension medium, but it took higher value when the ε value or the primary particle radius, γ_o, was smaller, or in the presence of a dispersing agent. In the case of larger γ_o, the curves of q against ε were located near the theoretical curves of q=ε^-1/4, which was derived from the two equations, f=ε^3/2 and q=√(ε/f). The former had been derived by Tobias for concentrated suspensions. Reduced viscosity η_1sp/C and structural viscosity index n showed higher values when ε and γ_o values were lower. Both η_1sp/C and n decreased in the presence of dispersing agents. Both q and η_1sp/C increased markedly for ε values of over 0.80, and also n increased markedly for ε values of over 0.70. Both η_1sp/C and n increased when q value was over 1.15. It was concluded that q, -η_1sp/C, and n are correlated with each other and vary according to the difference of ε, γ_o, and γ_m/γ_o.

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Adding sodium pyruvate to 1/2 strength medium yielded higher plate counts for a river bacterial community. Maximal counts were obtained when 0.15g liter^-1 of sodium pyruvate was added to the medium for both river water and epilithon samples. The degree of magnification of the plate counts on the medium supplemented with sodium pyruvate varied depending on the source of the sample. The findings suggested that the variations in magnification reveal aspects of physiological activities of microbial communities in river environments.

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The effect of moderate UV-irradiation (45J/m²) on species diversity of asporogenic heterotrophic bacterial isolates from paddy field soil was studied. Although the isolates from irradiated Petri dishes had less pronounced hydrolytic abilities and eutrophs were less numerous, irradiation did not result in specific selection of UV-resistant bacteria. Species diversity indices were higher for the set of isolates from irradiated dishes. This can be due to the fact that the number of cells inoculated onto irradiated dishes was about one hundred higher than onto control dishes; there may be a greater chance for soil bacteria of minor groups to form isolated colonies on irradiated dishes.

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Four species of indole-degrading Clostridium and 3 species of skatole-degrading Clostridium were isolated from piggery or chicken manure composting processes. Since type strains of respective isolates did not degrade these compounds, the degradability of the compounds was a novel characteristic. All isolates were mesophilic. The maximum growth allowance concentrations of these isolates were 300 to 800mg/l in indole and 100 to 300mg/l in skatole. All isolates showed better growth and utilization of indolic compounds in nutrient-rich medium than in minimal medium. Skatole-degrading isolates degraded some substituted indoles tested, 3-indoleacetic acid, indole and oxindole, but did not degrade 1-methylindole, 2-methylindole, isatin or anthranilic acid. On the other hand, indole-degrading isolates degraded only oxindole. The growth of Clostridium malenominatum A-3 was inhibited by a low concentration (0.005%) of indole or skatole, even when 200-fold excess glucose was present in the medium. When 0.03% indole or skatole was added to the medium, C. malenominatum A-3 showed a lag phase for about 10 and 70h, respectively. When 0.01% of these compounds was added to the medium, the uptake of glucose was inhibited. C. malenominatum A-3 degraded these compounds under nutrient-rich and minimal conditions.

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Cellular polyamine fraction of alkaliphilic Bacillus species was analyzed by HPLC. 2-Phenylethylamine was found selectively and ubiquitously in the five strains belonging to Bacillus cohnii within 27 alkaliphilic Bacillus strains. A large amount of this aromatic amine was produced by the decarboxylation of L-phenylalanine in the bacteria and secreted into the culture medium. The production of 2-phenylethylamine may serve for the chemotaxonomy of alkaliphilic Bacillus.

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Benzo[a]pyrene (B[a]P), one of polycyclic aromatic hydrocarbons (PAHs), is a ubiquitous environmental pollutant and a potent mutagen and carcinogen. To sensitively detect the genotoxicity of PAHs in complex mixtures extracted from environmental pollutants, Salmonella enterica serovar Typhimurium (S. typhimurium) strain YG5161 is engineered by introduction of plasmid 768 carrying the dinB gene encoding Escherichia coli DNA polymerase IV into standard Ames tester strain S. typhimurium TA1538 (Matsui et al., DNA Repair in press). Strain YG5161 exhibits higher sensitivity to the genotoxicity of B[a]P and other PAHs than do strain TA1538 and TA98. As the conventional Ames tester strains do, however, strain YG5161 also detects the mutagenicity of aromatic amines and nitroaromatics with high sensitivity, which may veil the genotoxicity of PAHs in complex mixtures. S. typhimurium possesses strong enzyme activities of nitroreductase and O-acetyltransferase, which mediate the metabolic activation of aromatic amines and nitroaromatics and enhance the potent genotoxicity. In this study, we disrupted the nfsB and oat genes encoding the activation enzymes in strain TA1538 to reduce the cross sensitivity, and introduced plasmid 768 into the ΔnfsBΔoat strain. The resulting strain YG5185 retained similar high mutability to various chemicals including PAHs as did strain YG5161 and substantially decreased the sensitivity to 1-nitropyrene, 1,8-dnitropyrene and 2-amino-6-methyldipyrido[1,2-a:3′,2′-d]imidazole (Glu-P-1). We propose that the novel tester strain YG5185 is useful to specifically and sensitively detect the genotoxic PAHs in complex mixtures from various polluted environmental sources.

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ペチュニアの育種に新たな知見を得るために,ウルグアイを中心に分布するPetuniapubescens(2n=18)とP.Pygmaea(2n=18)を母親として,広義のペチュニア46分類群との交雑を試みた.P.pmbescensとP.Pygmaeaに2n=14の分類群を交配した場合は,すべての組み合わせでさく果が得られなかった.一方,P.pubescensはP.ParvifloraおよびP.pygmueaを除くすべての2n=18の原種と交雑可能であった.P.pygmaeaはP.Parviflora以外との交雑はできなかった.この結果,2n=18のPetunia原種には2群[(1)P.ParvifloraとP.pygmaeaのグループ,(2)残りの種のグループ]が認識され,Petunia原種はその交雑親和性によって,少なくとも3群(2n=18の2群と2n=14の1群)に分けられることが分かった.

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The effect of media composition on the selection of different components of a mixed microbial population during serial transfer was examined. The initial microbial populations were from the small intestinal contents of 3- and 8-day-old piglets. Selection in brain-heart infusion broth was compared with selection in media based on piglet diets, either piglet feed infusion or sow colostrum. Clostridium and Lactobacillus were the predominant organisms isolated from media prepared from sow colostrum and piglet feed, although the microflora from piglet feed infusion broth was more varied and complex. Lactobacillus and non-hemolytic Escherichia coli were the predominant organisms identified from brain-heart infusion broth. Nearly half (48%) of the microflora from brain-heart infusion broth originally inoculated with intestinal fluid from an 8-day-old piglet consisted of non-hemolytic E. coli. E. coli were not detected after serial transfer in either sow colostrum or piglet feed infusion broths. Absence of E. coil was attributed in part to the presence of inhibitory substance(s) in sow colostrum and piglet feed infusion broths and in part to the presence of organisms antagonistic to E. coli. Bifidobacterium A, Clostridium F, and Lactobacillus F, which comprised 24% of the isolates obtained after serial transfer in sow colostrum broth, were antagonistic toward E. coil as well as were Bifidobacterium C, Lactobacillus G, and Leptotrichia A, which accounted for 38% of the isolates obtained after serial transfer in piglet feed infusion broth.

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