The author investigated the effect of N,N'-bis(decyldimethyl)-1,6-hexane diammonium dibromide on vegetative cells and spores of Clostridium perfringens type A. The investigated substance caused in concentrations of 1.0-4.0 micrograms.ml-1 escape of K+ from clostridia cells. At higher concentrations-2.0-16.0 micrograms.ml-1-high molecular components of the cytoplasmic material escaped. The author investigated the effect of the mentioned substance on germination of spores of Clostridium perfringens type A, using concentrations of 10, 20 and 40 micrograms.ml-1. The lower concentration of the substance (10 micrograms.ml-1) did not inhibit the onset of germination of spores of the tested strain, however, the post-germination development was retarded, as compared with controls. Germination of spores of Cl. perfringens type A in the presence of higher concentrations of the compound (20 and 40 micrograms.ml-1) was affected already in the initial stage. The germinating spores were most sensitive to the action of the substance when it was added after 60 and 120 min. following activation of spores for germination. The tested substance reduced the thermal resistance of Cl. perfringens type A spores.
Sepsis is due to its lethality, which varies round 25%, one of the major problems of contemporary clinical medicine. Classical therapeutic approaches, i.e. chemotherapy, surgical elimination of foci and intensive therapy focused on maintenance of vital functions have obviously reached the limit of effectiveness beyond which they are unable to advance any further. Therefore great efforts are devoted to research into pathogenetic mechanisms involved in sepsis with the aim to use their effect to improve therapeutic results. In the submitted paper the authors analyze the definition of sepsis, explain the concept of the syndrome of systemic inflammatory response and summarize the contemporary state of knowledge of the pathogenesis. A review of structures and mechanisms involved in the genesis and development of sepsis (complement, factor XII, macrophage, endothelial cell, polymorphonuclear leucocyte, thrombocyte etc.) is supplemented by a list of substances which act as mediators of inflammations. The conclusions for practice summarize contemporary therapeutic possibilities, i.e. classical means as well as more recent approaches (colony stimulating factors, haemodiafiltration, antithrombin III, monoclonal antibody against endotoxin). The authors review briefly therapeutic means which are developed at present and which should make it possible to interfere actively with the pathogenesis of the disease.
Due to world-wide use of 3rd generation cephalosporins and new beta-lactam antibiotics (imipenem, aztreonam), serious problems emerge caused by the appearance and spread of bacterial strains resistant also to these drugs. While the resistance to ceftazidime, cefotaxime and other "stable" cephalosporins has a transferable character and is plasmid-coded, the resistance to imipenem is transmissible only by bacteriophages. New enzymes in resistant bacteria bind specifically with the metoxyimino moiety of the molecule of these drugs. It is assumed that cephalosporins without the metoxyimino-group (4th generation) and new variants of imipenem (1-methyl-carbapenems, like meropenem and biapenem) will dominate therapy with betalactam antibiotics in the future.
The typical clinical picture and mycological and histological basis of chromomycosis is compared with the clinical course, which is encountered more often nowadays. It refers also to the affection of the vascular, respiratory, lymphatic system, the brain and the dissemination in compromised patients. For this reason chromomycosis should rank among opportunistic mycoses. Chromohyphomycosis characterized by skin nodules occurs very rarely. Subcutaneous abscesses also called phaeomycotic cysts, are more frequent especially after corticoid and immunosuppressive therapy. Among three Czechoslovak cases of chromomycosis, the case in Pilsen can be evaluated as uncommon. It was caused by Phialophora pedrosoi and passed as a skin form of chromomycosis. The lesion developed on the right forefinger of a patient who never visited tropical countries. She never was seriously ill, never treated with antibiotics, chemotherapeutics, or corticosteroids. The histological examination of the excision revealed a granuloma with histiocytes and many giant cells phagocytizing typical spherical brown microorganisms. The patient was cured by KI, intraiodine and X-ray therapy.
The author gives an account of another 77 species of micromycetes and some varieties of micromycetes which supplement the alphabetical list of 163 fungi which infect man, prepared by Otcenásek and Dvorák in 1985. Problems of medical mycology are discussed.
The authors characterize individual tests of the STAPHYtest Lachema and some other selected tests by calculating their discriminating capacity on 16 types of staphylococci which are most frequently isolated in clinical microbiological laboratories. Individual tests are characterized by the separating value, as described by Gyllenberg and Rypka, the variation index of Sneath and the consistency index. As regards discrimination, tests involving fermentation of trehalose, sucrose and glycerol are of no value. Conversely more important tests are lacking--sorbitol, melisitose, ONPG, DNA-ase, arginine.
Examinations of 1,998 ticks Ixodes ricinus in the district of Olomouc revealed 182 cases of borrelia, i.e. in 9.1% ticks. Prevalence in males is 10.7%, in females 12.8% and in nymphs 7.0%. A certain coincidence was observed between mosquito incidence, in particular during the first half of the year, and borrelia prevalence in ticks in the course of the following year, with prevalence variations manifested in tick imagos only. A hypothesis is formulated that mosquitos feeding on larger animals, who are often attacked by nymphs of I. ricinus ticks, can increase the infection rate in the hosts by borrelia transmission and thus participate in the increase of tick imago prevalence during subsequent years.
The authors describe the finding of Actinomyces viscosus in pus from a subdural empyema in a child patient. When searching for the probable primary source of this uncommon infection of the central nervous system the authors identified by cultivation the same bacterial strain in a periapical dental granuloma. Bacterial diagnosis and radical surgical and antimicrobial therapy led to normalization of a clinical condition with an initially unfavourable prognosis.
Using the second generation test, the authors examined 320 health professionals of the Faculty Hospital in Plzen and dialyzation centres in Karlovy Vary and Sokolov for the presence of antibodies against the hepatitis C virus. Antibodies were detected in 7 of them (2.2%). Serum positivity was confirmed only in paramedical workers, the highest herd immunity was recorded in workers in the dialyzation centre in Plzen. The authors evaluate the prevalence of antibodies in relation to age and period of practice in the health services.
It was revealed that a diameter of the inhibition zone of 10 mm or more surrounding a disk with 0.04 U bacitracin differentiates reliably strains of the serological group A form strains of group C and G with the exception of 7.3% strains of group C and G with a high susceptibility for bacitracin. The disks with a higher bacitracin content gives less reliable results.
The ELISA reaction with uniform serum dilution (1:400) for assessment of toxoplasmatic antibodies class IgG agreed in 100% when compared with commercial kits (VIRELISA and GULL Lab.). Both these tests disagreed with the standard complement fixation reaction in 7.5% of the specimens. This qualitative disagreement was confirmed also in a group of 400 sera where 7.14% of CFR negative specimens reacted positively in the described ELISA reaction. Quantitative correlation of results of CFR and ELISA IgG displays the usual scatter of values. Therefore individual CFR titres cannot be matched unequivocally with titres of optic density and thus it is not possible to assess empirically the stage of infection. To assess the stage of infection it is therefore necessary to make a supplementary assessment of IgM antibodies. In cases detected in time the decision can be based on a rise of IgG values in paired serum specimens examined in one reaction. Dynamics of formation of IgG antibodies and their chronological sequence with IgM antibodies displayed a typical course in patients with clinical toxoplasmosis. The described reaction is the basis of commercially manufactured kits ELISA IgG Toxo Micro II.
The authors tried to standardize the method of assessment of the minimal inhibitory concentration (MIC) of antimycotics for the evaluation of the sensitivity of opportunistic causal agents of mycoses. They paid attention to factors which cause deterioration of the reproducibility of tests and lead to intra- and interlaboratory variability of results. In conjunction with this the authors drew attention to the lack of uniformity of views on the application of these tests in clinical practice. In the author's view the reservation pertaining in particular to an inadequate correlation of results in vitro and in vivo do not cast doubts on the expedience of laboratory assessment of sensitivity. Testing of systemic antimycotics with a low pharmacotherapeutic index and a relatively high frequency of secondary resistance is particularly justified. In those instances assessment of MIC values is a significant component of monitoring of adequate antifungal chemotherapy, in particular when antimycotics are administered for prolonged periods to patients with altered immunity.
In conjunction with an investigation extending over several years, focused on the understanding of the importance of Helicobacter pylori in inflammatory gastric disease, the authors examined a group of 1242 patients. In fifteen they detected by microscopic examination the presence of helical bacteria described in the literature as Gastrospirillum hominis. The cultivation test was not positive. In three patients in addition to these bacteria also the presence of Helicobacter pylori was detected. Sera of eight patients with Gastrospirillum hominis were investigated by the ELISA test Helico-G f. Porton Cambridge; antibodies against Helicobacter pylori were found in three patients (incl. two with the concurrent presence of G.h. and H.p.). In sera of the remaining five patients antibodies were not detected.
The dynamics of bacteremia on white mice subcutaneously infected with an inoculum of 100 and 10 cells of F. tularensis (strain 273) was compared in two parallel experiments. The rise of bacteremia was relatively uniform, about 3 logarithms a day in both groups of animals, so that it reached values of 10(9)-10(10) cells per 1 ml of blood ante finem. Larvae of Ixodes ricinus were fed on white mice in different stages of bacteremia, so that groups of ticks with different degrees of infection were obtained. Our results of quantitative examination show an evident correlation between the degree of bacteremia of the host and the degree of infection of ticks. The highest values of positivity 10(6)-10(7) cells were recorded in larvae, which finished their feeding on the day of the host's death, during the time when bacteremia was reaching the highest degree 10(10) cells per ml of the blood. Persistence of the agent in the organism of infected larvae could be observed up to hatching, under given experimental conditions one month after infection. In nymphs developed from larvae with the highest degree of infection this ability was preserved in about one third of individuals still after 5 months of starvation. In ticks with low degrees of infection it disappeared during the experiments.
Based on assembled data from the literature and oral communications as well as findings in the laboratory, the author concludes that an enteroviral aetiology of diarrhoeal diseases can be taken for granted in many instances. Enteroviral gastritis is not frequent nor serious and is usually not encountered in winter but rather in summer under conditions with a higher standard of hygiene. The ratio of enteroviruses in epidemics of gastroenteritis and in the aetiology of enteritis within the framework of epidemics with other manifestations of enteroviral disease is very variable and there is no generally valid frequency which could serve for orientation. Virological and serological diagnosis of enteroviral diarrhoea would not be expedient in winter, it is, however, useful in summer and in epidemics affecting neonates and young children. In general, less attention is paid to an enteroviral aetiology or diarrhoea, as compared with thorough assessment of an enteroviral aetiology in severe forms of the disease. Attention is drawn to the usefulness of a more detailed investigation of properties of strains of polioviruses isolated from patients with diarrhoea.
In Escherichia coli strains isolated from faeces and smears from the rectum in haemolytic-uraemic syndrome of a child and healthy relatives the authors assessed the biochemical activity, antigenic characteristic, sensitivity to twelve antimicrobial substances and factors of virulence. Sorbitol negative strains were isolated from the ill child and his father. The strains belonged into serogroup 016. The remaining strains were sorbitol positive. They belonged into serogroups 02, 012 and 019. Nineteen sorbitol negative strains of E. coli from the sick child caused mannose sensitive agglutination of chicken and guinea pig erythrocytes, they produced colicin V and aerobactin. Except for one strain they were serum resistant. Fourteen strains induced the oedema on the foot of mice and eleven produced a lethal effect in mice. Except for three ampicillin resistant strains the remaining were sensitive to the examined antibacterial substances. Two sorbitol negative strains of E. coli isolated from the asymptomatic father produced aerobactin and one strain was serum resistant.
Semipurified urease and outer membranes of Helicobacter pylori were isolated and used as antigens for the construction of new ELISA tests for the serodiagnosis of infections caused by this microorganism. The highest discriminating capacity between infected and not infected subjects was obtained by the test detection of IgG antibodies against the urease antigen which reached a 100% sensitivity, 90% specificity, a 100% negative and 91% positive predictive value. Examination of sera of healthy children and blood donors revealed the possibility of asymptomatic infection and an increase of specific antibody levels with age.
Based on the long-term follow-up of the incidence of some infectious diseases in the district and calculations of the actual number of infected subjects, the authors present an estimate of the ratio of susceptible and immune subjects during the unimpaired epidemic process. The epidemic process develops from the lowest range of immune subjects and stops at the highest range. The highest range thus gives the ratio of immune subjects which must be achieved or maintained by active immunization to achieve elimination of a given infection. The authors demonstrate on the model infection the mechanism by which after immunization the shift of infections to higher age groups occurs, and during introduction of the infection not only contact infections occur, but epidemic incidence develops. The restoration of some infections after years of elimination is to a restricted extent a natural phenomenon and does not imply failure of active immunization.
The authors present examples demonstrating that in the last decades we witnessed the discovery of new nosological units and their infectious agents, the detection of the infectious origin of "old" diseases the aetiology of which was still recently obscure, infectious attacks of people by diseases which were considered animal infectious only, as well as the more frequent incidence of opportune infections due to impairment of the immune state of the human organism. These changes have many reasons such as the development of properties of microorganisms, lifestyle changes of the human population, advances in medicine, and last but not least improving microbiological diagnosis. Attention is drawn to the fact that even in a time when so-called diseases of civilization are in the foreground of interest our awareness of infectious diseases must not slacken. Only all-round international surveillance can prove successful.
