- Volume 12, Issue 4, 1979

The effect of active immunisation on muscle damage after systemic infection with Candida albicans was examined in a murine model. Mice were successfully immunised against acute muscle damage by vaccines of viable, nonviable, or disrupted C. albicans. In addition, markedly enhanced survival of immunised mice was demonstrated over a 4-week interval. There was protection against muscle damage in immunised mice without a reduction in the number of organisms present in cardiac tissue. The data indirectly implicate the role of humoral immunity in the protection afforded by immunisation.

Mixtures of mutant organisms of an invasive (IN) strain, a strain enteropathogenic (EP) for calves, lambs and piglets, and a non-pathogenic (NP) strain of Escherichia coli, that could be differentiated from each other by their antibiotic resistances, were given orally to an immunoglobulin-negative (IG—) and an immunoglobulin-positive (IG+) calf, lamb and piglet. By the use of appropriate antibiotic-containing culture media, the concentrations of organisms of each of the three strains in the contents of the alimentary tracts and tissues (liver, spleen, kidney, blood and mesenteric lymph glands) of the animals were estimated when they were killed. In the three IG — animals, the IN strain proliferated in the tissues and the EP strain proliferated in the small intestines; in general, the concentrations of the IN strain in the small intestines and the EP strain in the tissues, apart from the mesenteric lymph glands, were as low as those of the NP strain in these sites. The only strain that proliferated in the small intestine of the IG + animals was the EP strain, which proliferated in the small intestine of the calf and piglet; no organisms of either strain were isolated from the tissues of these three animals, except from their mesenteric lymph glands.

The prevalence of urinary-tract infection (UTI), diagnosed by examination of a single midstream urine from sexually active women was found to be 6.4%. Significant bacteriuria was most common in women who presented within 24 h of coitus but was not related to the number of sexual partners. UTI occurred significantly more often in women who presented within 4 days of intercourse than in women seen after a longer interval. Whether frequency of intercourse affects the prevalence of UTI remains to be determined.

The second documented instance of opportunistic infection by member of the genus Oerskovia is reported. There is some evidence to suggest that this group of bacteria, which is extensively distributed in the soil, may be more closely associated with man than has hitherto been supposed.

A unique and characteristic bacteriocine-like inhibitor elaborated by M-type 4, T-pattern 4, group-A streptococci was isolated and partially purified. This inhibitor was found to be produced optimally in Todd-Hewitt broth; after extraction and concentration, was shown to be protein in nature, and to have a m.w. of c. 8000. It was extremely heat stable and acid tolerant, but was quickly inactivated in alkaline conditions. It could be demonstrated in cell-bound form, but 99.5% was found in culture supernates. It was specifically adsorbed by viable sensitive cells, and its mode of action was bacteristatic.

A method is described in which washed whole cells of Corynebacterium parvum were chemically and enzymatically extracted to remove cytoplasm and cell-wall lipids. The resultant insoluble cell-wall residue possessed lympho-reticular stimulating properties as measured by their ability to increase spleen weight and protect against tumour-cell challenge. Analysis of the final product by chromatography and infrared spectroscopy has shown it to consist of carbohydrate and peptidoglycan, both of which appear to be necessary for the activities measured.

IgA and IgG antibodies to the ribonucleoprotein component of rubella virus have been demonstrated by radioimmune precipitation in sera from patients with recent but not remote rubella infection. This observation suggests that a test for antibodies to the ribonucleoprotein component may provide additional evidence in the diagnosis of recent rubella infection.

The spore antigens of Clostridium sporogenes,C. histolyticum, C. bifermentans and the butyric group were compared. By spore agglutination and fluorescent-antibody technique (FAT) the 69 strains of C. histolyticum were divided into two types: serum raised against type I (66 strains) reacted with all strains of this species but showed no cross reaction with any of the three types of C. sporogenes; serum raised against type II (three strains) did not react with strains of C. histolyticum type I but showed cross reaction with all the 66 strains of C. sporogenes type I. Thus, by antigenic analysis, spores of C. histolyticum type I were found to possess two components designated E and F; E was a type-specific component whilst F was shared by strains of type II. In addition, strains of C. histolyticum type II possessed a second component, G, which was shared by strains of C. sporogenes type I. There was no cross reaction between the precipitinogens of the spores of the two species. Five strains of C. bifermentans formed a homogeneous group as judged by spore agglutination, FAT and precipitation reactions. There was no cross reaction with any of the other proteolytic species studied. Five butyric strains also formed a homogeneous group. Two antigenic components were therefore assigned to the spore antigens of the two groups: J, for C. bifermentans and K, for the butyric strains.

Polymorphonuclear leucocytes selectively inhibited the incorporation of 14C-uridine by intracellular staphylococci. Within specified limits, the amount of radiolabel incorporated by extracellular staphylococci was related to bacterial concentration. The incorporation of labelled uridine can thus be exploited to assay the extent to which association between staphylococci and polymorphonuclear leucocytes reflects surface adherence as opposed to ingestion. A comparison of the new method with a conventional viable-count determination of leucocyte-associated bacteria shows it to be comparable in efficiency when non-immune serum is used as opsonin and superior when specific opsonin is used.

Electronmicrographs of sections show that the L-phases of Bacillus licheni-formis var. endoparasiticus (Benedek) simulate the various types of microorganism described by previous workers as associated with ostensibly non-infective conditions, notably cancer and arthritis; e.g., mycoplasmas, myco-bacteria, corynebacteria and actinomycetes. The stages of the L-cycle, from spheroplasts through smaller and larger ‘diphtheroid’ bacteria to the fully reverted sporogenous bacillus, differ from one another mainly in their degree of reconstitution of the cell envelopes. Occurrence in ‘diphtheroids’ of non-resistant, cell-wall-deficient spore-like bodies, confirms their relationship with the true sporing bacillus stage. Large, swollen forms appear to be mother cells of minute stages.

We examined the results of tests with 22 substrates for their ability to discriminate a series of 917 strains of Escherichia coli collected from different sources. The tests with three of the substrates were discarded because of difficulties in performance or interpretation, and another nine substrates because they provided little discrimination. The tests used to obtain biotype profiles for strains were those for the fermentation of dulcitol, D-raffinose or sucrose or both, L-rhamnose and L-sorbose, the decarboxylation of L-lysine and L-ornithine, the hydrolysis of aesculin, motility, and prototrophy.

Observations on several series of cultures from different sources showed that biotype characters were stable in vivo and after storage on non-selective medium. The biotype profiles obtained were as reliable as partial O serotyping for the routine subtyping of strains of E. coli isolated from the urine of patients with long-term urinary-tract infections and those from other sources in different patients. Biotyping and O serotyping used in conjunction offered a very fine degree of strain discrimination.

Several adsorbent materials were evaluated for their ability to bind Escherichia coli enterotoxins. Cholestyramine, a strong anion-exchange resin, bound the heat-labile and the heat-stable types of enterotoxin and reduced significantly their effects in some animal models. However, its efficacy in the treatment of diarrhoeic piglets ppeared to be adversely affected by the presence of milk in the alimentary tract.