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[Evaluation of the lysozyme and DNAase activity for the identification of pathogenic staphylococci].

The sensitivity of two tests recently proposed for the classification of pathogen staphylococci were evaluated: --production of DNA-ase with the modified method of Lachica et al.; --production of lisozyme. The two above tests were studied with other six tests on 1,000 strains of staphylococci showing a very high specificity. The Authors propose that the DNA-ase production and the lisozyme production, also for their very simple execution, should become routine tests to identify the strains of pathogenic staphylococci.

Deoxyribonucleases

Utility of newer techniques for classification and identification of pathogenic anaerobic bacteria.

Results of genetic and biochemical analyses have broadened our understanding of taxonomic relationships among groups of anaerobic bacteria and have led to a better understanding of the pathogenesis of infection. Conventional bacteriologic methods are still of prime importance for the detection and identification of anaerobic pathogens. The use of nucleic acid probes has so far been restricted to research laboratories. A polymerase chain reaction-generated probe would be most useful for the rapid detection of toxigenic Clostridium difficile in feces. Probes are needed for detection of periodontopathogenic bacteria in dental plaque. Use of nucleic acid probes may become a useful adjunct to classic methodology in reference and teaching laboratories.

Bacteria, Anaerobic

New aspects of staphylococcal infections: emergence of coagulase-negative staphylococci as pathogens.

In contrast to the well-established pathogen Staphylococcus aureus, the coagulase-negative staphylococci, formerly collectively called S. epidermidis, were until recently regarded as harmless commensals. During the last two decades, however, the coagulase-negative staphylococci have clearly emerged as pathogens in patients carrying artificial devices, such as prosthetic heart valves, hip prostheses and cerebrospinal fluid shunts, and in patients with compromised host defenses such as premature neonates and cancer and transplant patients. The present paper reviews current insights on classification, bacteriology, pathogenic potential and virulence factors of coagulase-negative staphylococci. In addition, the role of host defense factors in resistance to staphylococcal infection is summarized as well as the main features of the clinical syndromes in which coagulase-negative staphylococci are involved.

Antibodies, Bacterial

[Characteristics and classification of plasmids of conditionally pathogenic E. coli according to their conjugative and mobilization capacity].

A number of conjugative plasmids of opportunistic E. coli with molecular weights of 23.6--81.8 megadaltons have been studied. On the basis of the data thus obtained conjugative F-like R-plastmids have been subdivided into 2 groups characterized by the unsuppressed or suppressed manifestation of their functions. Individual conjugative plasmids have been found to differ in their capacity for mobilizing non-conjugative SuSm plasmid for transfer, which indicates the possibility of using this test for characterization and classification of plasmids, identified in natural bacterial population.

Animals

The medically important aerobic actinomycetes: epidemiology and microbiology.

The aerobic actinomycetes are soil-inhabiting microorganisms that occur worldwide. In 1888, Nocard first recognized the pathogenic potential of this group of microorganisms. Since then, several aerobic actinomycetes have been a major source of interest for the commercial drug industry and have proved to be extremely useful microorganisms for producing novel antimicrobial agents. They have also been well known as potential veterinary pathogens affecting many different animal species. The medically important aerobic actinomycetes may cause significant morbidity and mortality, in particular in highly susceptible severely immunocompromised patients, including transplant recipients and patients infected with human immunodeficiency virus. However, the diagnosis of these infections may be difficult, and effective antimicrobial therapy may be complicated by antimicrobial resistance. The taxonomy of these microorganisms has been problematic. In recent revisions of their classification, new pathogenic species have been recognized. The development of additional and more reliable diagnostic tests and of a standardized method for antimicrobial susceptibility testing and the application of molecular techniques for the diagnosis and subtyping of these microorganisms are needed to better diagnose and treat infected patients and to identify effective control measures for these unusual pathogens. We review the epidemiology and microbiology of the major medically important aerobic actinomycetes.

AIDS-Related Opportunistic Infections

Primary amoebic meningoencephalitis.

As a serendipitous by-product of polio virus research, a highly fatal amoebic meningoencephalitis was recognized in animals. The causative microorganisms, contaminants of the viral cultures, were identified as small soil amoebae. These organisms, previously considered non-pathogenic, are prevalent throughout the world. Based on animal studies, the original investigators suggested the possibility of a similar disease in humans. Seven years later, human cases of amoebic meningoencephalitis were reported from widely separated areas of the world. Since 1965, a total of 79 cases have been reported. The literature of primary amoebic meningoencephalitis is presented. The history of the discovery and elucidation of this disease is reviewed. The 79 cases reported in the world literature are divided into two groups, those diagnosed retrospectively after reviewing previous deaths from meningoencephalitis, and those diagnosed at the time of the illness. The classification, morphology, pathogenicity, virulence and distribution of pathogenic soil amoebae are reviewed. The presenting clinical findings, diagnostic procedures, pathology, and management of this recently recognized, highly fatal, human disease is presented along with a report of a new case. Otolaryngologists should become familiar with this serious disorder with a transnasal portal of entry.

Amebiasis

Escherichia coli serogroup O111 includes several clones of diarrheagenic strains with different virulence properties.

Genetic variation among isolates of Escherichia coli O111 obtained mostly from patients with diarrhea in Brazil was assessed by multilocus enzyme electrophoresis to characterize chromosomal genotypes and by gene probes and adherence assays to characterize virulence properties. Among the 152 isolates, we resolved 16 distinct electrophoretic types (ETs), which differed on average at 40% of the enzyme loci. We identified four major bacterial O111 clones of different disease classes: ET 12, which includes the bulk of the enteropathogenic E. coli strains, typically showing localized adherence and intimate attachment in tissue culture assays; ET 1, which includes strains with a different set of virulence markers; ET 9, which includes strains that show intimate attachment but lack localized adherence and Shiga-like toxin genes; and ET 8, which includes strains that are Shiga-like toxin producers and have the corresponding traits of enterohemorrhagic E. coli. Enteroaggregative strains constituted ET 10 and also occurred in ET 1. Isolates of the major clones were found in South and North America and matched in ET and virulence factors to previously described diarrheagenic clones that are widely disseminated in the human population. Because the major clones are genetically distantly related and exhibit different combinations of virulence factors, we hypothesize that they have distinct mechanisms of pathogenesis. The results indicate that genetic divergence of bacteria with the O111 antigen, as measured by allelic variation in enzyme loci, is accompanied by divergence in virulence properties of clones so that identification and classification of pathogenic E. coli strains cannot be based solely on serotyping or a single virulence factor.

Bacterial Adhesion

Large-scale functional annotation establishes a reference framework for human LRRK2 variants.

Pathogenic variants in leucine-rich repeat kinase 2 (LRRK2)1are among the most frequent monogenic causes of Parkinson's disease (PD)2 and act through a gain-of-function mechanism of increased kinase activity. LRRK2-targeted therapies are in clinical development, but interpretation of the rapidly expanding catalogue of rare LRRK2 variants remains a barrier to translation. Here, we present functionally annotated data on >350 LRRK2 coding variants using a standardized cellular assay with Rab10 phosphorylation as a readout of kinase activity and integrated these data with curated genetic and clinical annotations from the Movement Disorders Society Genetic Mutation Database (MDSGene). Variants differed in activation magnitude, ranging from modest increases (e.g., p.G2019S) to strongly activating substitutions such as p.Y1699C or p.L1795F. Activating variants occurred across the full length of LRRK2, although the largest effects clustered within the ROC-COR regulatory hub, where structural analysis identified subdomains forming an allosteric scaffold controlling kinase output. All known/established pathogenic variants showed increased activity, whereas benign and likely benign variants remained within the wild-type range. Functional effect sizes correlated with pathway activation in patient-derived immune cells, altogether providing a framework for ACMG-based variant interpretation in which kinase activation can support PS3 functional evidence for reclassification of variants.

Protein phosphorylation

[Teeth extractions on diabetics patients].

In this paper the writer primarily mentions the temporary theories on the classification and pathogenic origin of diabetes. Furthermore, he describes the most important etiological factors of the appearance of the disease and its clinical picture. He specially extends to mentioning the probability of appearance of acute complications during dental help to a diabetic patient. He also underlines that the degree the reformatory functions of the organism are influenced by the interference of chronic complications which he describes. After maintaining the basic precautionary lines during the extraction of teeth in diabetic patients he describes the basic approach necessary in case of acute complications of diabetes. In the paper are also mentioned the latest methods of direct calculation of the level of glucose both to blood and the urine of the patient.

Blood Glucose

X-ray microanalysis as applied to fungal tissues.

Analytical electron microscopy combines the techniques of high-resolution electron microscopy and high-sensitivity X-ray microanalysis of samples. Spectrometry of the elements (characteristic X-rays produced by a scanning electron microprobe) was employed to detect some elements of Mendeleev's classification in pathogenic fungi for humans. X-ray microanalysis applied in wavelength dispersive spectrometry was used to study Coccidioïdes immitis, Paracoccidioïdes brasiliensis and Trichosporum cutaneum.

Coccidioides

[Urethro-adnexitis in the man and acute urethral syndrome in the woman. Microbiological and immunologic studies of etiologic classification].

Both common pathogens and unconventional, fastidious bacteria, viruses, parasites, and fungi are causative agents in male urethro-adnexitis and in female acute urethral syndrome. Uropathogens, Neisseria gonorrhoeae, Treponema pallidum, Mycobacterium tuberculosis, Chlamydia trachomatis, Mycoplasma spp., Haemophilus ducreyi, Calymmatobacterium granulomatis, Gardnerella vaginalis, anaerobic bacteria, Herpes simplex virus type II (HSV II), papillomaviruses (HPV), Trichomonas vaginalis and Candida spp. must be considered. The various diagnostic procedures and criteria applied for aetiological classification in cases of balanitis, urethritis, prostatitis, epididymitis, orchitis, and acute urethral syndrome are reviewed and evaluated.

Acute Disease

[Classification of septicemias. A clinical and pathogenic approach].

Classic sepsis is characterized by the presence of bacteria in blood originating from a primary infection site with secondary location at other sites. Some infectious diseases like typhoid and paratyphoid fever, brucellosis an others share this pathogenetic mechanism but have a characteristic clinical course and usually a good prognosis. After analyzing the differences between the 2 types the author proposes the terms "non specific" and "specific" for each type of sepsis, respectively. The differences between the 2, the organism involved and different reaction of the host in types, may be related to different pathogenetic effects of each case.

Brucellosis