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At least 217 records · Page 12Linked to original sources
PubMed1981

Early diagnosis and prompt treatment by surgery in Jorge Lobo's disease (keloidal blastomycosis).

In 1931 the Brazilian doctor Jorge Lobo examined a patient from the Amazon Basin who had nodular confluent skin lesions over the lumbosacral region and encountered a new fungus pathogenic for man Paracoccidioides loboi. This classification was based on the morphological aspect of the parasite which was very similar to Paracoccidioides brasiliensis the causative agent of a systemic mycosis Paracoccidioidomycosis or South American Blastomycosis. Other authors use the name Loboa loboi. The final determination of the name must await cultivation of the fungus.

Adult↗
PubMed1988

Infections caused by antibiotic-resistant Corynebacterium group D2.

A coryneform bacteria known as Corynebacterium group D2 pending definitive taxonomic classification, has emerged as a human pathogen. Although first described 16 years ago, the organism has only recently been implicated in clinical infections. It differs from all previously recognized species of Corynebacterium, and in common with Corynebacterium jeikeium exhibits a broad spectrum of antimicrobial resistance, being sensitive to only vancomycin, teicoplanin and some quinolones. The microorganisms is mainly involved in urinary tract infections, and its strong urease activity seems to play an important role in its pathogenicity. Corynebacterium jeikeium and group D2 are very different from the clinical and microbiological point of view. Corynebacterium group D2, like other coryneform bacteria, may be isolated from healthy skin in hospitalized patients, mainly females, while Corynebacterium jeikeium is more prevalent in males. Microbiologists should be aware that such a slow-growing microorganism may be responsible for clinical infections and should not be overlooked in routine cultures of clinical specimens.

Anti-Bacterial Agents↗
PubMed1990

Phylogenetic analysis and identification of different serovars of Mycobacterium intracellulare at the molecular level.

Comparative 16S rRNA sequencing was used to infer the phylogenetic relationship among different serovars of the Mycobacterium avium-M. intracellulare complex as well as to define signature nucleotides characteristic for different serovars. In general, the groups defined by rRNA sequencing reflect the classification obtained with sensitin tests and pathogenicity examinations in chickens. Unique 16S rRNA sequence patterns could be defined for (1) M. avium, (2) M. intracellulare serovars 4, 5, 6, 8, 9, 10 and 11, (3) M. intracellulare serovars 12, 13, 14, 15, 17, 19 and 20, (4) M. intracellulare serovar 7 and (5) M. intracellulare serovar 18. Phylogenetically, groups 1 and 2 on one hand and groups 3, 4 and 5 on the other hand each share a common ancestor. M. paratuberculosis was indistinguishable from M. intracellulare serovars 4, 5, 6, 8, 9, 10 and 11 by this kind of analysis.

Base Sequence↗
PubMed1975

Clinical aspects of bilateral renal dysplasia in children.

Despite recent attempts to improve classification and to provide data on pathogenic mechanisms, there is a paucity of information concerning the clinical aspects of bilateral renal dysplasia. Therefore, the clinical features and long-term prognosis of eight patients with bilateral renal dysplasia have been evaluated. Three important observations were made, namely (1) a large proportion of patients had an impairment of urinary concentration and acidification, (2) the clinical course was characterized by progressive renal deterioration in patients with bilateral involvement, and (3) four children with renal dysplasia had the clinical features of Laurence-Moon-Biedl syndrome.

Adolescent↗
PubMed1992

A cohort study of coagulase negative staphylococcal mastitis in selected dairy herds in Prince Edward Island.

The epidemiology and importance of coagulase negative staphylococcal (CNS) mastitis in Prince Edward Island had not been documented. To investigate this, a cohort of 84 cows at seven farms were quarter sampled eight times over a lactation, commencing with samples taken prior to drying off in the previous lactation. Thirteen species of CNS were isolated. The quarter prevalence of CNS mastitis varied from 4.8% to 6.4% in the first five months of lactation and increased to 14.2 to 16.6% in the last four months of lactation. The geometric mean somatic cell counts (SCC) for quarters infected with CNS and uninfected quarters were 90 x 10(3) and 64 x 10(3) respectively (difference significant at p > 0.005). The two month new infection risk of CNS was 9.0% while the two month elimination risk was 74.4%. Infection with CNS did not alter the risk of subsequent infection with Staphylococcus aureus. The results from this project support the classification of CNS as a minor pathogen in mastitis control programs.

Animals↗
PubMed1980

[Cephalic neural crests and disorders of craniofacial morphogenesis. Neurocristopathies (author's transl)].

To establish the pathogenicity, and attempt to define a classification of craniofacial malformations is a difficult task, both in animals and humans. Mention is often made of the classification developed by Paul Tessier, which according to this author "is neither based on a theory nor on an embryonic definition. It is the by-product of anatomical findings during clinical examination and operative dissections" (31). The authors propose an embryologic classification of facial malformations, based on disorders of embryonic development of cells derived from the neural crests (NC) of cephalic origin, and constituting the craniofacial ectomesenchyme. The importance of the cephalic NC derivatives in craniofacial morphogenesis is stressed, and the principal malformations of the cephalic shelf outlined, as a function of disorders occurring during the formation of the NC; migrations, proliferation, and differentiation of their derivatives. The main objective of this study was to formulate pathogenetic hypotheses, to propose a classification, and to stimulate interest in further studies in the realm of physiological and pathological craniofacial morphogenesis.

Bone Diseases, Developmental↗
PubMed2019

Pediatric Cancer Variant Pathogenicity Information Exchange (PeCanPIE): a cloud-based platform for curating and classifying germline variants.

Variant interpretation in the era of massively parallel sequencing is challenging. Although many resources and guidelines are available to assist with this task, few integrated end-to-end tools exist. Here, we present the Pediatric Cancer Variant Pathogenicity Information Exchange (PeCanPIE), a web- and cloud-based platform for annotation, identification, and classification of variations in known or putative disease genes. Starting from a set of variants in variant call format (VCF), variants are annotated, ranked by putative pathogenicity, and presented for formal classification using a decision-support interface based on published guidelines from the American College of Medical Genetics and Genomics (ACMG). The system can accept files containing millions of variants and handle single-nucleotide variants (SNVs), simple insertions/deletions (indels), multiple-nucleotide variants (MNVs), and complex substitutions. PeCanPIE has been applied to classify variant pathogenicity in cancer predisposition genes in two large-scale investigations involving >4000 pediatric cancer patients and serves as a repository for the expert-reviewed results. PeCanPIE was originally developed for pediatric cancer but can be easily extended for use for nonpediatric cancers and noncancer genetic diseases. Although PeCanPIE's web-based interface was designed to be accessible to non-bioinformaticians, its back-end pipelines may also be run independently on the cloud, facilitating direct integration and broader adoption. PeCanPIE is publicly available and free for research use.

Child↗
PubMed1982

Fatty acid composition of mycobacterial lipids as an index of pathogenicity.

Five species of Mycobacterium were analyzed for the fatty acid composition of total and neutral lipids and of individual classes of phosphatides. The methyl esters of fatty acids were analyzed using the technique of gas liquid chromatography. It was found that myristic, palmitic, palmitoleic, and tuberculostearic acids were the major fatty acids present in all of the lipid components of these strains of tubercle bacilli. The ratio of unsaturated to saturated fatty acids is lowest in the most pathogenic strain, indicating a progressive increase in this ratio, and the highest ratio is represented by a saprophytic strain. An avian pathogenic organism falls in the center of this classification among the examined strains of mycobacteria. These results indicate that the ratio of unsaturated to saturated fatty acids of lipids can be used to determine and establish the pathogenic species of mycobacteria.

Animals↗
PubMed2003

[New fungal classification and their applications in medicine].

Fungi are gaining importance with the increased incidence of invasive, often fatal mycoses, in immunocompromised patients. In addition, the increased number of emerging opportunistic pathogens has prompted interest in studies pertaining to fungal classification. The traditional methods of identification and classification of these microorganisms are based on the morphology of the sexual and asexual reproductive structures. Recently, this system of classification has been shown incongruent with approaches that better establish phylogenetic relationships among these organisms. Novel aspects of fungal reclassification are described as follows: 1) the position of fungi in the historical classification systems, 2) the recognition of their polyphyly, based on comparative studies of nucleic acid sequences and on analysis of descent lines and, 3) the contribution of molecular phylogeny to medical mycology, including identification of mycotic agents, their molecular epidemiology, prevention of infection and methods of diagnosis.

Fungi↗
PubMed1977

[Classification of acute bacterial enteropathies].

The first part considers pathogenic microorganisms (Vibrio cholerae and parahaemolytic vibrio, Clostridium welchii, enteropathogenic E. coli, Shigella, Salmonella, other enterobacteria and pseudomonas. Yersinia, simply enterotoxic Staphylococcus and that producing acute enteritis) and the process of infection (formation of a surface link without endocellular penetration with elaboration of hexotoxins, formation of a surface link with subsequent intracellular penetration, submucosa penetration). The second part discusses Salmonellae on the basis of personal experience. Particular attention is paid to current aspects of Salmonella microbiological pathomorphosis, the various isolated serotypes in relation to carriers or patients, biochemical atypias of Salmonellae strains, present-day aspects of resistance to chemoantibiotic treatment and the transfer of Salmonella Wien resistances.

Bacterial Infections↗
PubMed1996

Demonstration of antigenic and genotypic variation in Orientia tsutsugamushi which were isolated in Japan, and their classification into type and subtype.

A total of 40 strains of Orientia tsutsugamushi (34 isolates from patients and trombiculid mites in Japan, and 6 prototype strains of antigenic variants) were examined for classification based on the reactivities with type-specific monoclonal antibodies in indirect immunofluorescence tests, and on the restriction fragment length polymorphism of a polymerase chain reaction (PCR)-amplified 56-kilodalton type-specific antigenic protein gene. By these methods, several antigenic and genotypic variants were found among the strains, and these variants were classified into types and further into subtypes. These results suggest that there are many variants in O. tsutsugamushi, and the methods used here seem to be useful for the systematic classification of the numerous variants. A strain which may be a new type distinguishable from those identified previously was also found in this study. Furthermore, variety in the degree of pathogenicity in mice related to type and/or subtype classification were observed.

Animals↗
PubMed2002

Validation using sensitivity and target transform factor analyses of neural network models for classifying bacteria from mass spectra.

Temperature constrained cascade correlation networks (TCCCNs) are computational neural networks that configure their own architecture, train rapidly, and give reproducible prediction results. TCCCN classification models were built using the Latin-partition method for five classes of pathogenic bacteria. Neural networks are problematic in that the relationships among the inputs (i.e., mass spectra) and the outputs (i.e., the bacterial identities) are not apparent. In this study, neural network models were constructed that successfully classified the targeted bacteria and the classification model was validated using sensitivity and target transformation factor analysis (TTFA). Without validation of the classification model, it is impossible to ascertain whether the bacteria are classified by peaks in the mass spectrum that have no causal relationships with the bacteria, but instead randomly correlate with the bacterial classes. Multiple single output network models did not offer any benefits when compared to single network models that had multiple outputs. A multiple output TCCCN model achieved classification accuracies of 96 +/- 2% and exhibited improved performance over multiple single output TCCCN models. Chemical ionization mass spectra were obtained from in situ thermal hydrolysis methylation of freeze-dried bacteria. Mass spectral peaks that pertain to the neural network classification model of the pathogenic bacterial classes were obtained by sensitivity analysis. A significant number of mass spectral peaks that had high sensitivity corresponded to known biomarkers, which is the first time that the significant peaks used by a neural network model to classify mass spectra have been divulged. Furthermore, TTFA furnishes a useful visual target as to which peaks in the mass spectrum correlate with the bacterial identities.

Bacteria↗
PubMed1995

Practical approach to the management of prostatitis.

The management of prostatitis remains a frustrating problem for the clinical urologist. The various disease processes are poorly understood, the clinical presentation is extremely variable, the definitive diagnosis is difficult, and treatment is dismal. A sound clinical approach to the diagnosis and treatment of the various prostatitis syndromes by clarifying the etiology, rationalizing the classification, and describing a practical plan for diagnosis and a common sense approach to treatment is presented in this article. A combination of dysfunctional voiding and intraprostatic reflux of urine (sterile or infected) is the underlying pathogenic mechanism. Prostatodynia should be dropped from the classification of the prostatitis syndromes and should be relegated to the role of the most important differential diagnosis. Physicians who have abandoned the standard three-glass test of Meares and Stamey should consider the Pre- and Post-Massage Test (PPMT) for the diagnosis of prostatitis. An understanding of the pathogenic and etiologic mechanisms along with an appreciation of the importance of correct diagnosis at first presentation combined with a knowledge of the latest treatment studies will lead to improved management and treatment of patients with prostatitis.

Bacterial Infections↗
PubMed2026

Expansion of the allelic and phenotypic spectrum of MED25-related developmental disorder: novel compound heterozygous variants with structural domain implications.

MED25-related developmental disorder (Basel-Vanagaite-Smirin-Yosef syndrome) is a rare autosomal recessive disorder, defined by severe neurodevelopmental delay, corpus callosum abnormalities, ocular involvement, epilepsy, and marked facial appearance. MED25 pathogenic variants interfere with the functioning of the Mediator complex, which is responsible for RNA polymerase II transcription. We report a 9-year-old girl who presents with significant global developmental delay, agenesis of the corpus callosum, congenital cataracts, epilepsy, hypotonia, musculoskeletal abnormalities, and typical craniofacial features. Trio-based whole-exome sequencing revealed compound heterozygous variants in MED25: a maternally transmitted truncating variant (c.1366 C > T; p.Gln456*) and a paternally inherited missense variant (c.430 C > T; p.Leu144Phe). The new classification of the missense variant as potentially pathogenic is supported by a systematic ACMG re-evaluation supported by segregation analysis, phenotypic specificity, computational prediction, and structural localization in the MED25 Activator Interaction Domain (ACID). Comparative phenotypic analyses show strong agreement with reported cases but add more data to fine-tune clinical spectrum. This article broadens the allelic and phenotypic spectrum of MED25-related developmental disorder and highlights the need for comprehensive evaluation across molecular, structural, and phenotypic pathways to elucidate variant signature in rare genetic disease models correctly.

Humans↗
PubMed1990

[Pathogens and pathogenesis of dermatophytoses].

The principles of taxonomic and systematic classification of dermatophytes are described with an emphasis on the relevance of teleomorphic forms. Special attention is given to their relation to dimorphic fungi and the formation of arthroconidia as a parasitic growth form. The main factors contributing to pathogenicity of dermatophytes are explained, including enzymes (especially keratinases), allergens and leukotaxins. Genetic predisposition and the unspecific (serum factors, polymorphoneutrophilic granulocytes) and specific immunological mechanisms of host defence are differentiated and critically evaluated.

Arthrodermataceae↗