Dekkera intermedia and Brettanomyces custersii were shown to have a respiratory pathway resistant to cyanide, antimycin A, and azide. This respiration remained sensitive to salicylhydroxamic acid (SHAM). The “cyanide-resistant” respiration was induced mainly at the end of the growth phase and could reach 50% of total respiratory capacity.
The mitochondrial “petite colony” mutation had no effect on this oxidation pathway. The presence of this respiration pathway in these strains constitutes a compensation mechanism for the reducing activity of acetaldehyde dehydrogenase. This alternate pathway would thus be a fundamental element of the Custer effect, a characteristic feature of these strains.

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Enterotoxigenic Escherichia coli strains were isolated from the feces of 34.4% of 64 diarrheaic neonatal piglets on seven farms. Of a total of 518 isolates, 86 (16.6%) were enterotoxigenic and grouped into four phenotypes: K99⁺ST⁺ (K99 pilus antigen and heat-stable enterotoxin producing, 36 strains), ST⁺ (37 strains), K88⁺LT⁺(K88 pilus antigen and heat-labile enterotoxin producing, 11 strains), and K88⁺ST⁺ (2 strains). K99⁺ST⁺ and ST⁺ isolates showed multiple drug resistance and most of those (58.3% and 56.8% respectively) belonged to O serogroup 101. A K99⁺ST⁺ isolate proved to be capable of inducing diarrhea and death in hysterectomy-produced colostrum-deprived piglets when orally inoculated.

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A few yeast mannans free from protein and phosphorus showed pyrogenic activity in rabbits although the extent of this activity was considerably lower than that of the bacterial lipopolysaccharides (LPS). The pyrogenic actiity was not abolished by treatment with sodium deoxycholate. This result showed that the mannans themselves participated in the pyrogenicity, excluding any possibility of LPS contamination in the mannans. Concerning the relationship between chemical structure and pyrogenicity of these mannans, it was demonstrated that a mannan possessing a highly branched structure exhibited stronger pyrogenicity than that of a less branched one.

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Previously we showed that Klebsiella O3 lipopolysaccharide (KO3 LPS) is much more potent than other kinds of LPS including Escherichia coli O127 LPS (EO127 LPS) in adjuvant activity in augmenting antibody response and delayed-type hypersensitivity to protein antigens and in the ability to enlarge the regional lymph node. Various defined uniform salt forms, the triethylamine, sodium, potassium, ammonium, tris(hydroxymethyl)aminomethane, and calcium salt forms, of KO3 LPS and EO127 LPS were prepared by removing basic materials present in LPS preparations by electrodialysis and neutralizing the electrodialyzed LPS preparations with various kinds of alkali. The triethylamine salt form showed the best solubility and consisted of the smallest granules and, on the other hand, the calcium salt form showed the lowest solubility, compared with the natural form and the other uniform salt forms. Even if the natural forms of KO3 LPS and EO127 LPS were converted to the defined uniform salt forms, adjuvanticity of KO3 LPS and EO127 LPS in augmenting delayed-type hypersensitivity to ovalbumin and the ability to enlarge the regional lymph node did not significantly differ from those of the respective natural forms. From these results it is concluded that the difference in strength of the adjuvanticity between KO3 LPS and EO127 LPS is not due to the difference in their salt forms, solubility or physical state. Moreover, there were no significant differences in lethal toxicity for mice by the intraperitoneal route among the natural form and all the uniform salt forms of KO3 LPS tested.

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Environmental mycobacteria in Korea have been investigated by examining 54 soil, 111 house dust, 63 well water, and 98 sewage samples collected from 123 randomly selected areas in Korea during the fourth nationwide tuberculosis prevalence survey in 1980.
A variety of mycobacteria were isolated from 76% of soil, 67% of sewage, 43% of well water, and 7% of house dust samples. Sortie samples yielded more than one species; thus 56 strains were obtained from soil, 107 strains from sewage, 48 strains from well water and 8 strains from house dust. Mycobacterium fortuitum was the most common species of environmental mycobacteria in Korea and the species was distributed equally in all types of samples tested. The M. terrae complex was also one of the common species of environmental mycobacteria and it seemed to be more abundant in water samples than in soil. Scotochromogenic slow growers M. scrofulaceum and M. gordonae were common microbes in soil and water samples, although the latter was more frequently detected in water samples. Scotochromogenic rapid growers M. flavescens and M. phlei, and photochromogenic rapid grower M. vaccae were isolated more frequently from sewage or water samples than from soil. Nonphotochromogenic rapid growers M. chelonei (chelonae) and M. smegmatis were isolated mostly from sewage and the former was rarely found in soil and well water samples. The clinically important species M. avium-intracellulare complex was found less frequently in all types of test samples.

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Oral administration of adenovirus strain K87 to BALB/c nude mice resulted in viral proliferation in the intestinal tract up to around week 6 at which point replication was suppressed. In other words, the host acquired resistance. However, this resistance was temporary and the viral infection persisted over a long period with repeated periods of proliferation and resistance. That the appearance of this resistance is the result of infecting mice with the virus and is not due to age difference per se was made clear through experimentation with nude mice of different age groups. However, it was indicated that increase in age is involved in the decreased rate of reproliferation following initial suppression. No evidence of the virus was obtained from any other organ throughout the infection. Furthermore, throughout the persistent infection, even during the aforementioned periods of resistance, no neutralizing antibody was detected from sera, intestinal wall or intestinal content. When spleen cells from BALB/c heterozygous littermate mice was transferred to the nude mice, an earlier onset of antiviral resistance was seen than in nude mice without the transfer, and this was accompanied by a rise in neutralizing antibody titer. From these results, it is believed that the resistance characteristic of nude mice infected by mouse adenovirus is dependent on some factor other than the neutralizing antibody invoked resistance exhibited by euthymic mice.

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During the course of an investigation designed to separate macrophage activating factor (MAF) activity from interferon (IFN) antiviral activity in the lymphokine-rich fraction (LKF) produced by stimulation of murine splenic cells with concanavalin A (Con A), we found molecular evidence for the similarity of the two activities. MAF activity was expressed as the rate of inhibition of intracellular growth of Salmonella typhimurium in macrophages based on the linear correlation between relative MAF activity and LKF concentration. The antiviral substance in LKF was identified as IFN-γ based on the observation that its activity was inactivated at pH 2 and neutralized with anti-mouse IFN-γ serum but not with anti-mouse IFN-α/β serum. MAF and IFN antiviral activities displayed identical sensitivity to pH 2 and temperature. Further, neither activity was affected by β-mercaptoethanol, but both were inactivated by guanidine hydrochloride and by sodium dodecyl sulfate, suggesting that the structures related to conformation of the protein of the two molecules may be similar. In affinity chromatography of the LKF on a Con A-Sepharose column, MAF and IFN activities were found in both the nonadsorbing (F I) and adsorbing (F II) fractions. However, the rates of F II of MAF and IFN activities increased proportionally when the sample was applied on a column of higher capacity, suggesting that the molecular structure of the mannose-containing glycosyl moiety of the two molecules may also be similar. Moreoer, the intact or modified form of MAF and IFN activities of different LKF preparations showed a strong correlation, indicating that the production and denaturation of MAF activity were proportional to those of IFN antiviral activity. The results of this study provide strong evidence that MAF and IFN antiviral activities may reside in virtually the same molecular species.

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The present study demonstrated the presence of cells belonging to monocyte/macrophage lineage which suppressed mitogen-induced blastogenesis of peripheral blood lymphocytes in cynomolgus monkeys. Depletion of adherent or phagocytic cells from peripheral mononuclear cells caused a substantial increase in the blastogenic response of cynomolgus monkey lymphocytes whereas the same treatment led to marked reduction rather than enhancement in human lymphocyte blastogenesis. Addition of thioglycollate-elicited peritoneal exudate adherent cells as macrophages suppressed the blastogenic response of nonadherent lymphocytes in a dose-dependent manner. The suppressive effect was observed not only in autologous but also in allogeneic macrophages to the responder lymphocytes. Treatment of macrophages with silica, carrageenan or freezing-thawing reduced their suppressive effect but there was no reduction with mitomycin C or indomethacin. No suppressive activity was detected in the cell-free supernatant of macrophages cultured in the presence or absence of mitogens for up to 4 days. From these findings, it appeared that monocyte/macrophage lineage might be responsible for the observed suppressive effect on mitogen-induced blastogenesis of cynomolgus monkey lymphocytes.

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