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PubMed1998

Internalization and cytotoxicity are important virulence mechanisms in Vibrio-fish epithelial cell interactions.

Vibrio anguillarum and Vibrio damselae are Gram-negative bacteria that cause systemic infections called vibriosis in fish. They can enter fish cells and survive as intracellular parasites. The host-pathogen interactions between these Vibrio species and the fish epithelial cell lines epithelioma papillosum of carp (EPC) and grunt-fin tissue (GF) cells, were examined using phase-contrast, scanning electron and confocal microscopy. In addition, potential signal transduction pathways that precede bacterial internalization were studied by using signal transduction inhibitors. Some Vibrio species induced morphological changes in fish cells and this allowed classification into a cytopathic group and a noncytopathic group. The cytopathic group could be subdivided into two invasive groups (I and II) and a cytotoxic group. Of the invasive strains V. anguillarum 811218-5W (group I) and G/Virus/5(3) (group II), genistein, a tyrosine kinase inhibitor, only inhibited internalization of V. anguillarum G/Virus/5(3) into EPC cells, whereas staurosporine, a protein kinase C inhibitor, accelerated internalization of both strains. Cytochalasin D, an inhibitor of microfilament polymerization, prevented internalization of both strains, whilst vincristin, a microtubule inhibitor, only inhibited internalization of V. anguillarum G/Virus/5(3). For the cytotoxic strain V. damselae ATCC 33539, extracellular products (ECP) alone caused morphological changes in EPC and GF. Bacterial internalization may not be important in the pathogenesis of this group. The non-cytopathic strain V. anguillarum S2/5/93(2) did not enter cells or induce any changes in EPC and GF monolayers. This study has identified some major differences between Vibrio species in their interactions with fish cells in vitro and will thus facilitate future studies of the molecular basis of pathogenesis of vibriosis.

Animals↗
PubMed2003

Infective endocarditis due to Streptococcus bovis in a series of nonaddict patients: clinical and morphological characteristics of 20 cases and review of the literature.

BACKGROUND AND OBJECTIVES: Controversy frequently exists about the actual frequency of Streptococcus bovis infective endocarditis (IE), its incidence of malignancy and its outcome. Consequently, the characteristics of S bovis IE were examined in an unselected population of nondrug-addicted patients. The literature was also reviewed. METHODS: Nondrug-addicted patients with S bovis IE were retrospectively reviewed. Clinically definite IE was diagnosed according to the Duke classification criteria at the single reference hospital for a defined population in northwestern Spain over a 13-year period. The clinical features, need for surgery and mortality rate of these patients were compared with those of other nondrug-addicted patients with IE examined during the same time period. RESULTS: Between 1987 and 1999, S bovis IE was diagnosed in 20 consecutive patients. This pathogen was responsible for 16.8% of the cases of definite IE in nondrug-addicted patients. Underlying conditions and embolic septic events were common. The aortic valve was the most common site of IE. Simultaneous involvement of two cardiac valves and moderate to severe regurgitation were more common in patients with S bovis IE. Colonic neoplasms were observed in 77% of patients. However, in-hospital mortality rate, need for in-hospital surgery and surgery during follow-up did not differ between patients with S bovis IE and the other nondrug-addicted patients with IE. CONCLUSIONS: In unselected patients, the rate of mortality due to S bovis IE is similar to that observed in IE due to other microorganisms. However, colonoscopic evaluation during admission and follow-up is required.

Aged↗
PubMed1984

Myasthenia gravis and myasthenic syndromes.

More than a decade ago myasthenic symptoms were observed in rabbits immunized with acetylcholine receptor (AChR) [119] and AChR deficiency was found at the neuromuscular junction in human myasthenia gravis (MG) [36]. By 1977 the autoimmune character of MG and the pathogenic role of AChR antibodies had been established by several measures. These included the demonstration of circulating AChR antibodies in nearly 90% of patients with MG [87], passive transfer with IgG of several features of the disease from human to mouse [149], localization of immune complexes (IgG and complement) on the postsynaptic membrane [30], and the beneficial effects of plasmapheresis [20, 123]. Substantial subsequent progress has occurred in understanding the structure and function of AChR and its interaction with AChR antibodies. The relationships of the concentration, specificities, and functional properties of the antibodies to the clinical state in MG have been carefully analyzed, and the mechanisms by which AChR antibodies impair neuromuscular transmission have been further investigated. The clinical classification of MG has been refined, the role of the thymus gland in the disease has been further clarified, and new information has become available on transient neonatal MG. The prognosis for generalized MG is improving, but there is still no consensus on its optimal management. Novel therapeutic approaches to MG are now being explored in animal models. Recognition of the autoimmune origin of acquired MG also implied that myasthenic disorders occurring in a genetic or congenital setting had a different cause. As a result, a number of congenital myasthenic syndromes have come to be recognized and investigated. Finally, an acquired disorder of neuromuscular transmission different from MG, the Lambert-Eaton myasthenic syndrome, has also been shown to have an autoimmune basis. In this syndrome, active zone particles of the presynaptic membrane are direct or indirect targets of the pathogenic autoantibodies.

Acetylcholinesterase↗
PubMed2005

Molecular identification of pathogenic house dust mites using 12S rRNA sequences.

House dust mites are microarthropods implicated in the cause of allergic diseases. Currently, there is no phylogenetic analysis of dust mites based on genomic or mitochondrial DNA (mtDNA) evidence. For the first time, we report evolutionary relationships based on partial mtDNA 12S rRNA sequences among the four dust mite families Pyroglyphidae (Dermatophagoides pteronyssinus), Glycyphagoidea (Glycyphagus privatus), Acaridae (Aleuroglyphus ovatus), and Echimyopodidae (Blomia tropicalis). Thirteen sequence variants were obtained and phylogenetic analysis showed two monophyletic clades composed of two species each. Contrary to current taxonomic classification, the Acaridae clustered in a monophyletic group with the Pyroglyphidae. Considering the current difficulties in identifying these medically important species for the purpose of eradication and treatment, it is significant that sequence data are capable of discriminating between species belonging to different families of dust mites.

Acaridae↗
PubMed2003

Validation of data collection for the HEDIS performance measure on chlamydia screening in an MCO.

OBJECTIVE: To determine the validity of calculating the chlamydia Health Plan Employer Data and Information Set (HEDIS) measure using administrative data available in a mixed-model managed care organization (MCO). STUDY DESIGN: Retrospective cohort study. METHODS: A review of International Classification of Diseases, Ninth Revision (ICD-9), Current Procedural Termin-ology (CPT), Healthcare Common Procedure Coding System (HCPCS), and National Drug Code codes and electronic laboratory files in 1998 and a medical chart review to validate sexual activity and chlamydia testing codes specified by the National Committee for Quality Assurance (NCQA) in 1999 for the chlamydia HEDIS 2000 measure. RESULTS: Fewer than 25% of female enrollees with laboratory evidence of a chlamydia test had a CPT code for chlamydia testing as specified by the NCQA. Non-pathogen-specific test codes instead of NCQA-specified codes were used in 1998 to code chlamydia tests. By incorporating electronic laboratory data into the automated claims-generating process, all chlamydia tests performed at staff-model clinics were coded. Use of pharmacy dispensing data to identify contraceptive prescriptions increased the proportion of enrollees classified as sexually active by 4% to 5% vs documentation of sexual activity using ICD-9, CPT, and HCPCS codes only. CONCLUSIONS: The MCO quality assurance specialists examining chlamydia testing rates under HEDIS may want to evaluate chlamydia testing coding practices in their MCOs to determine whether simple changes in coding practices may present a more accurate picture of actual testing practices. The proportion of female enrollees classified as sexually active using different data available in the staff and network models varied only slightly.

Adolescent↗
PubMed2001

Evidence for multiple origins of human infectivity in Trypanosoma brucei revealed by minisatellite variant repeat mapping.

In recent years a wide variety of biochemical and molecular typing systems has been employed in the study of parasite diversity aimed at investigating the level of genetic diversity and delineating the relationship between different species and subspecies. However, such methods have failed to differentiate between two of the classically defined subspecies of the protozoan parasite Trypanosoma brucei: the human infective, T. b. rhodesiense, which causes African sleeping sickness, and the non-human infective T. b. brucei. This has led to the hypothesis that T. b. rhodesiense is a host range variant of T. b. brucei. In this paper we test this hypothesis by examining highly polymorphic tandemly repeated regions of the trypanosome genome, i.e., minisatellite loci. We have employed the technique of minisatellite variant repeat mapping by PCR (MVR-PCR), which determines the distribution of variant repeat units along the tandem array of one minisatellite, MS42. The maps generated by this technique not only allow unequivocal allele identification but also contain within them cladistic information which we used to determine the possible genetic relationship between the different subspecies of T. brucei. Our findings revealed that human infective (T. b. rhodesiense) isolates from Uganda are more closely related to the local non-human infective isolates (T. b. brucei) than they are to other human infective stocks from different regions, suggesting that human infectivity has originated independently in these different geographical regions. This would infer that the separate classification of all human infective stocks from East Africa into the subspecies T. b. rhodesiense is genetically inappropriate and it would be better to consider geographically separate populations as host range variants of T. brucei brucei or perhaps as a series of different subspecies. Based on these data, it is clear that MVR mapping is a very useful tool for the analysis of zoonotic eukaryotic pathogens where delineation of the origins of outbreaks of disease and definition of human infective strains are key questions.

Africa↗
PubMed2004

[Hematodermic CD4/CD56 neoplasm].

Hematodermic CD4/CD56 neoplasm is a recently described entity. This name has been initially proposed by the French Study Group on Cutaneous Lymphomas which established the primary anatomoclinical and pathogenic and cytogenic bases of the disease in 1999. This descriptive and provisional name allowed conceptualizing the entity by its main clinical and phenotypical characteristics. The first case in the literature goes back to 1994. Since that time, several other cases have been published. The expression of CD56 led most of the authors to propose an NK-cell lineage origin. In the last WHO classification of lymphomas, the entity was indexed under the name of "blastic NK-cell lymphoma". However, the authors underlined that there were currently no clues to the etiology of blastic NK-cell lymphoma and that the precise lineage of this disease was still unresolved. At the clinical level the main characteristics of the disease are the skin tropism and the occurrence of a leukemic phase at any time during the course of the disease. The median age is 59 but pediatric cases do exist. At the morphological level skin biopsy shows a monomorphous cell proliferation simulating a pleomorphic T cell cutaneous lymphoma. The diagnosis is based on phenotypic criteria which require frozen tissue. Currently, the main characteristics are the expression of CD4 and CD56 antigens while the main defined lineage specific markers are negative (B-cell, T-cell, NK-cell and myeloid-cell lineages). The origin of the tumor cells still remains uncertain but the plasmacytoid dendritic cell is presently a very serious candidate. The tumor cells share a great phenotypical homology and particularly the expression of the CD123 antigen. Functional homologies have also been demonstrated with tumor cells in vitro. Outcome of CD4/CD56 hematodermic neoplasms is very bad. The median time of survival is 14 months irrespective of the treatment given. Conventional chemotherapies used for the treatment of aggressive lymphomas or acute myeloid leukemias are quickly inefficient.

Adolescent↗
PubMed2000

Severity assessment in community-acquired pneumonia.

In current guidelines for the management of adults with community-acquired pneumonia (CAP), the triaging decision about hospitalization or intensive care unit (ICU) admission, and, as a consequence, selection of initial antimicrobial treatment is largely based on the assessment of pneumonia severity. The proposed severity criteria are mainly derived from studies determining predictors of adverse outcome. These include age, male sex, comorbidity, acute respiratory failure, severe sepsis and septic shock, extension of radiographic infiltrates, bacteraemia and CAP through several different pathogens such as Streptococcus pneumoniae, Staphylococcus aureus, Gram-negative enteric bacilli (GNEB), and signs of disease progression within the first 48-72 h. In addition, prediction rules and need for a complicated course in ambulatory and hospitalized patients, for the individual risk of death have been developed which may be helpful in determining the patient who might require hospitalization or intensive care, respectively. Risk classifications such as the scores developed by FINE et al. [40] are not only useful for identifying low risk patients who might safely be treated as outpatients, but apparently they will also play a major role in the evaluation of processes and outcomes of care for patients with CAP. Recent investigations have provided objective criteria for the definition of severe CAP requiring ICU admission. Whether the detection of infiltrates in the chest radiographs of patients with acute lower respiratory tract infection (LRTI) suggestive of mild pneumonia has an independent prognostic impact which fundamentally affects the concept of mild LRTI remains to be seen. Based on objective criteria for severity assessment it will be possible to define interventions aimed at reducing hospital admission rates, define a risk-adapted antimicrobial treatment regimen, reduce costs for antimicrobial treatment and supportive measures, shorten hospital stay, and, thereby, improve the quality of care for patients with community-acquired pneumonia.

Community-Acquired Infections↗
PubMed2001

Antibiotic therapy in intra-abdominal infections--a review on randomised clinical trials.

There have been 79 randomised antibiotic studies in intra-abdominal infections retrieved. The overall success rate of the studied antibiotics ranges from 70-100%. Unfortunately only about one fourth of the studies have used a disease severity classification, e.g., APACHE II score, despite clear recommendations by the Surgical Infections Society of North America. The mortality rate in the published antibiotic studies is still rather low (approximately 4%) and does not correspond to the average mortality in peritonitis (30-40%). Failure analysis is not uniform and only performed in about 1/5 of retrieved studies. Failure analysis included data on diagnosis, type of operation, pathogen isolated at first operation, susceptibility and persistence of pathogen, re-operation or change of antibiotic regimen, and follow-up (ICU duration, death or survival, hospitalisation). Only one study has performed an analysis of the adequacy of the surgical treatment (source control). The clinical success rate of the antibiotics studied in a larger population is comparable for gentamicin + clindamycin (80%), tobramycin + clindamycin (83%), meropenem (89%), imipenem (85%), aztreonam + clindamycin (89%), cefoxitin (88%), cefotetan (92%), moxalactam (83%), cefotaxime + metronidazole (87%), ampicillin/sulbactam (87%). Piperacillin/tazobactam has in most studies a success rate of approximately 90%. The aggregated data on adverse events and clinical failure rate do not show a major advantage for any of these antibiotics. It is striking that the adverse event rate reported for ticarcillin/clavulanic acid is low when compared to all other antibiotics, which is in contrast to severe adverse events reported for clavulanic acid. The data of quinolone studies in intra-abdominal infections do not yet allow a recommendation, even when it is acknowledged that two studies were performed with good results and a good study plan. In conclusion, the comparability of antibiotic studies in intra-abdominal infections is limited due to a lack of disease severity stratification and a relatively small study population for most antibiotics. The clinical success rate of the best-studied antibiotics is similar and the choice which antibiotic is used depends on the expected pathogens and the resistance rate in a clinical setting.

APACHE↗
PubMed1990

[Intestinal spirochetosis in homosexuals infected with HIV. 3 cases].

We report 3 cases of intestinal spirochetosis in homosexuals infected with the human immunodeficiency virus (2 group III and 1 group IV C1, according to the Centers for Disease Control classification) presenting with moderate, chronic diarrhea. The diagnosis was made based on the histological examination of colorectal biopsies showing a layer of spirochetes carpeting the epithelium. Electron microscopy evaluation and culturing of the microorganism provided information on the bacterium's morphology. Metronidazole effectively treated the diarrhea. Intestinal spirochetes, whose existence has been recognized for more than a century, constitute a heterogeneous group of bacteria whose pathogenic role in man remains controversial. The systemic search for these organisms in a large series of patients would help to situate their place among the various etiologies of infectious diarrhea in immunodepressed subjects.

Adult↗
PubMed1982

[Pathological anatomy of congenital hypotrophy].

The problems of etiology, pathogenesis, pathological anatomy, classification, and incidence of congenital hypotrophy in newborn babies are considered. Reduction in body weight and height of the newborns with congenital hypotrophy, weight of internal organs, developmental retardation, as well as dysplastic, atropic, and compensatory-adaptative processes are regularly observed. The intensity of these manifestations of congenital hypotrophy in newborn babies depends on the duration and potency of the prenatal effect of the pathogenic factors.

Anthropometry↗
PubMed2006

Structures and serology of the O-antigens of Proteus strains classified into serogroup O17 and former serogroup O35.

INTRODUCTION: Bacteria of the genus Proteus are facultative pathogens which commonly cause urinary tract infections. Based on the serological specificity of the O-chain polysaccharide of the lipopolysaccharide (O-polysaccharide, O-antigen), strains of P. mirabilis and P. vulgaris have been classified into 60 serogroups. Studies on the chemical structure and serological specificity of the O-antigens aim at the elucidation of the molecular basis and improvement of the serological classification of these bacteria. MATERIALS AND METHODS: The O-polysaccharide was prepared by acetic acid degradation of the lipopolysaccharide isolated from dried bacterial mass of each strain by hot phenol/water extraction. (1)H- and (13)C-NMR spectroscopy was used for structural studies. Serological studies were performed with rabbit O-antisera using enzyme immunosorbent assay, passive hemolysis test, and the inhibition of reactions in these assays as well DOC-PAGE and Western blot. RESULTS: Four Proteus strains belonging to serogroups O17 and O35 were found to possess similar O-polysaccharide structures, in particular having the same carbohydrate backbone built up of tetrasaccharide repeating units. However, they differ in the presence or absence of additional substituents, such as phosphoethanolamine in P. mirabilis O17 and glucose in P. penneri O17, as well as in the pattern and degree of O-acetylation of various monosaccharide residues. Serological studies also showed close relationships between the O-antigens studied. CONCLUSIONS: Based on these data it is proposed to reclassify strain P. mirabilis PrK 61/57, formerly representing the O35 serogroup, into the serogroup O17 in the Kauffman-Perch classification system of Proteus.

Carbohydrate Conformation↗
PubMed1975

Nephropathy associated with sickle cell anemia: an autologous immune complex nephritis. II. Clinicopathologic study of seven patients.

A variety of renal structural and functional abnormalities have been associated with sickle cell disease. To define the relationship between the hemoglobinopathy and glomerular disease, clinicopathologic correlations, renal morphologic, ultrastructural immunohistologic and functional studies were performed on seven patients with clinical and laboratory evidence of glomerular disease. In addition, immunologic studies including isolation and characterization of cryoprecipitable immune complexes, and determination of immunoglobulin, total complement and complement component levels, and antibody titers to several antigens were performed in an attempt to define the etiologic and pathogenic mechanisms of the renal disease and its relationship to sickle cell anemia. Proteinuria was presnet in all patients. The nephrotic syndrome, hypertension, hematuria and renal insufficiency were found in more than one half the patients. All patients had membranoproliferative glomerulonephritis of varying degree; glomerular basement membrane splitting, electron dense deposits in the glomerulus; interstitial fibrosis, tubular atrophy and hemosiderin deposits were frequent. Immunoglobulin complement components (classif complement pathway) and renal tubular epithelial antigen were distributed in a granular pattern along the glomerular basement membranes of all patients studied by these methods. Cyroprecipitable complexes of renal tubular epithelial antigen-antibody to renal tubular epithelial antigen as well as antibody to renal epithelial antigen were detected in the circulation of some patients. There was no serologic evidence of activation of the alternate complement pathway. These studies demonstrated an immune deposit normocomplementemic nephritis associated with sickle cell anemia; they further support our hypothesis that the relationship is more then coincidental, and is mediated by glomerular deposition of immune complexes of renal tubular epithelial antigen-antibody to renal tubular epithelial antigen, the antigen possibly released after tubular damage secondary to oxygenation and hemodynamic alterations related to sickle cell disease.

Adolescent↗
PubMed2001

Prostatitis.

Prostatitis is a common condition that accounts for a significant number of visits to both the emergency department and the urologist. The precise pathogenic mechanism of prostatitis is not known. The most prevalent theory is that reflux of urine from the urethra into the intraprostatic ducts promotes ascending infection and leads to chemical or bacterial prostatitis. Treatment is challenging because many antimicrobial agents do not effectively diffuse into prostatic tissue and many cases of prostatitis are not found to have an infectious etiology. Prostatitis can be divided into different classifications which range from acute severe infections, to chronic indolent infections, to chronic pain syndromes. The differentiation and management of these entities can be difficult. This article seeks to clarify the different infections, and provide a rational approach to treatment and disposition of these patients.

Acute Disease↗
PubMedDate not supplied

Guanine-plus-cytosine content, hybridization percentages, and EcoRI restriction enzyme profiles of spiroplasmal DNA.

The guanine-plus-cytosine (G + C) content of spiroplasmal DNA was calculated from the melting temperature determined spectrophotometrically and the buoyant density determined by equilibrium density gradient centrifugation in CsCl. Only two ranges of G + C values were found: 25-27 mol% and 29-32 mol%. The DNA of the following spiroplasmas has 25-27 mol% G + C: Spiroplasma citri (serogroup I-1); the spiroplasmas pathogenic to the honeybee (KC3, BC3, and B63; serogroup I-2); the corn stunt strain (E275; serogroup I-3); the tick strain 277F (serogroup I-4); the drosophila strain (serogroup II); and one group of flower spiroplasmas (serogroup III). The DNA of a second group of flower spiroplasmas (serogroup IV) and the SMCA strain (serogroup V) has a G + C content of 29-31 mol/. The classification of flower spiroplasmas into two groups on the basis of G + C content agrees well with the groupings based on serologic and protein analysis. Spiroplasmas isolated from honeybees in Morocco (B13) or froghoppers in Corsica (L89) have 29-31 mol% G + C, a value that corroborates the relatedness of these strains and the flower spiroplasmas of serogroup IV found by serologic analysis. Reannealing experiments between the vivo-labeled DNA of S. citri and unlabeled DNA of other spiroplasmas gave the following percentages of hybridization: 64% with honeybee spiroplasma DNA, 49% with corn stunt spiroplasma DNA, and 19% with tick spiroplasma 277F DNA; no significant hybridization was observed with DNA of any other spiroplasma. The taxonomic position of the tick spiroplasma 277F within serogroup I was confirmed by hybridization experiments involving [3H]DNA of this strain. The value of polyacrylamide gel analysis of DNA fragments produced by the action of EcoRI restriction enzyme on DNAs from various spiroplasmas is also discussed.

Animals↗
PubMed2006

FGDB: a comprehensive fungal genome resource on the plant pathogen Fusarium graminearum.

The MIPS Fusarium graminearum Genome Database (FGDB) is a comprehensive genome database on one of the most devastating fungal plant pathogens of wheat and barley. FGDB provides information on two gene sets independently derived by automated annotation of the F.graminearum genome sequence. A complete manually revised gene set will be completed within the near future. The initial results of systematic manual correction of gene calls are already part of the current gene set. The database can be accessed to retrieve information from bioinformatics analyses and functional classifications of the proteins. The data are also organized in the well established MIPS catalogs and novel query techniques are available to search the data. The comprehensive set of gene calls was also used for the design of an Affymetrix GeneChip. The resource is accessible on http://mips.gsf.de/genre/proj/fusarium/.

Databases, Genetic↗
PubMed2001

Francisella tularensis strain typing using multiple-locus, variable-number tandem repeat analysis.

Francisella tularensis, the etiological agent of tularemia, is found throughout the Northern hemisphere. After analyzing the F. tularensis genomic sequence for potential variable-number tandem repeats (VNTRs), we developed a multilocus VNTR analysis (MLVA) typing system for this pathogen. Variation was detected at six VNTR loci in a set of 56 isolates from California, Oklahoma, Arizona, and Oregon and the F. tularensis live vaccine strain. PCR assays revealed diversity at these loci with total allele numbers ranging from 2 to 20, and Nei's diversity index values ranging from 0.36 to 0.93. Cluster analysis identified two genetically distinct groups consistent with the current biovar classification system of F. tularensis. These findings suggest that these VNTR markers are useful for identifying F. tularensis isolates at this taxonomic level. In this study, biovar B isolates were less diverse than those in biovar A, possibly reflecting the history of tularemia in North America. Seven isolates from a recent epizootic in Maricopa County, Ariz., were identical at all VNTR marker loci. Their identity, even at a hypervariable VNTR locus, indicates a common source of infection. This demonstrates the applicability of MLVA for rapid characterization and identification of outbreak isolates. Future construction of reference databases will allow faster outbreak tracking as well as providing a foundation for deciphering global genetic relationships.

Animals↗
PubMed1986

Some remarks about laser-induced mass spectrometry of bacteria.

In order to investigate the availability of laser-induced mass spectrometry for the determination of bacteria, ten strains of the genera Escherichia and Streptococcus were chosen. Gram-negative as well as Gram-positive lysogenic and non-lysogenic, pathogenic and non-pathogenic strains were examined. Giant pulses of a Nd: YAG laser (frequency quadrupled, wave-length 265 nm) were used to vaporize and partly ionize the bacterial material. The time-of-flight mass spectra obtained could be discriminated by using the stepwise discriminant analysis provided by BMDP software package. Two different methods relating centrifugation and washing procedures were used. With the first method a correct classification between 50.0 and 90.9 per cent (S. sanguis) by means of mass spectra of positive ions and a correct classification between 27.1 and 80.4 per cent (S. lactis-25) by means of mass spectra of negative ions was observed. Using the second method a correct classification between 40.7 and 93.3 per cent (S. lactis-25) by means of mass spectra of positive ions and a correct classification between 56.7 and 95.0 per cent by means of mass spectra of negative ions was obtained. Here S. sanguis with 93.3 and S. lactis-25 with 81.7 per cent were significantly differentiated. In this context it must be emphasized that a correct classification of 27 per cent must be considered statistically significant, if 10 different strains are used.

Bacteria↗