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PubMed1981

Characteristics of listeria strains, isolated from micromammalia in Bulgaria.

56 Listeria strains isolated from the intestine contents of 13 species of micromammalia in Bulgaria were studied. 10 of the strains belong to the serovars 1/2a, 4A, 4b and 5 of Listeria monocytogenes and 44 of the strains belong to 10 antigenic variants of Listeria innocua. According to their characteristics these strains could hardly cause diseases in humans or domestic animals. Two strains have antigenic formulae O-V, VII, XIV and O-V, XIV and cannot be included in the existing classification. Prevalent are the strains antigen O-XV. They are more often isolated from synanthropic rodents. The hemolytic properties of the studied strains have the best correlation with the pathogenicity. The decomposition of rhamnose and xylose and the production of lysozyme could be a suitable basis for their classification in biotypes.

Animals↗
PubMedDate not supplied

The systemic vasculitides.

The systemic vasculitides include a heterogenous group of diseases, characterized by inflammatory and necrotic lesions of the vessel walls, with subsequent ischemic changes in different organs. Various factors are incriminated in the vasculitides etiology, despite the fact that, in most of the cases, the etiologic agents are unknown. The pathogenic mechanisms are generally mediated through circulant immune complexes, which induce the inflammatory reaction at the vessel wall site, accompanied by complex immune reactions. A classification of vasculitides should take into account the type of the injured vessel, the elements of the inflammatory infiltrate and the triggering pathogenic mechanisms. The definition and monitoring of the therapeutic regimen are difficult but, generally, the main elements of medication are represented by corticosteroid and cytotoxic drugs.

Humans↗
PubMed1975

A numerical taxonomic study of coryneform and related bacteria.

Two hundred and thirty-three strains of coryneform bacteria, including representatives of the genera Arthrobacter, Brevibacterium, Cellulomonas, Corynebacterium, Erysipelothrix, Jensenia, Kurthia, Listeria, Microbacterium, Mycobacterium, Nocardia and Propionibacterium and other related bacteria, were studied using 173 morphological, physiological and biochemical tests. The bacteria were grown on a soil extract medium which allowed growth of all the strains, and all were incubated at 30 degrees C. The results were subjected to computer analysis. The majority of the strains grouped into eight main clusters representing: (A) Lactobacillus, Listeria, Microbacterium thermosphactum and Streptococcus faecalis; (B) Erysipelothrix and Streptococcus pyogenes; (C) animal corynebacteria and Microbacterium flavum; (D) Cellulomonas and related bacteria; (E) Propionibacterium; (F) Arthrobacter, Brevibacterium, Kurthia and Mycobacterium rhodochrous; (G) plant pathogenic corynebacteria; (H) Nocardia. Based on these clusters, several recommendations are made regarding the classification of the coryneform area. (i) The members of clusters A and B at present placed in the Corynebacteriaceae would seem better moved to the Lactobacillaceae. (ii) The genus Corynebacterium would best be retained for the types species C. diphtheriae, closely related animal corynebacteria and Micro. flavum. (iii) Cellulomonas and Propionibacterium are distinct taxa more closely related to Corynebacterium than to either Arthrobacter or Lactobacillus. (iv) Clusters F and G are evidently heterogeneous. In particular the positions of Kurthia and the plant pathogenic corynebacteria are unclear. Arthrobacter is a large loose taxon and it is premature to decide on its taxonomic rank. The genus Brevibacterium should be retained for B. linens and closely related strains. (v) The cellulolytic forms of Nocardia should be removed from the genus; they are however quite distinct from Cellulomonas.

Actinomycetales↗
PubMed1993

A nephrological view of the classification of vasculitis.

From the nephrologic perspective, a nomenclature system has been proposed that is clinically useful for diagnosis, classification and therapy. This nomenclature allows the nephrologist to consider the best approach to ANCA positive patients with necrotizing and crescentic glomerulonephritis. It allows for better understanding of the extra-renal manifestations of disease especially those with pulmonary-renal syndrome. The classification system allows for the rapid introduction of immunosuppressive therapy in individuals without repetitive search for specific pathological features on biopsy. This classification system allows for the possibility that all of these conditions are pathogenically related. As such, it separates this group of diseases from those which are attributable to immune complex disease or direct antibody binding. For this nomenclature system to stand the test of time it must be simple, logical and clinically usefully. While not yet perfected, the working nomenclature for ANCA-associated diseases is a step forward.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1988

Angels with wet wings won't fly: maternal sentiment in Brazil and the image of neglect.

Current theories of fatalism and neglect and current descriptions of childhood illness in impoverished Northeastern Brazil are evaluated. Findings of an ongoing multidisciplinary project indicate that neglect and fatalism theories are incomplete as applied to the Brazilian Northeast. Intensive interviews and observations with bereaved mothers and traditional healers show that mothers' failure to obtain medical care for severely ill children is due more to real-life bureaucratic and geographic barriers to access than to fatalistic or neglectful attitudes on the part of the poor, that mothers' flat affect in response to infant deaths is due more to folk Catholic beliefs than to lack of emotional attachment to infants, that fatalistic statements are often post hoc and do not indicate fatalistic behavior, and that decisions about whether to treat severely ill infants are made by mothers and families in consultation with traditional healers in accord with a folk system of classification of high risk infants. What have been described as "death accepting," "pathogenic," and "ethnoeugenic" attitudes are part of a folk ethical system developed to guide reactions to terminal childhood illness. We argue that human behavior, especially in the realm of health, cannot be understood without reference to both biomedical and psychosocial realities.

Adult↗
PubMed1991

Species identification and characterization of an Acanthamoeba strain from human cornea.

The isoenzyme pattern of an Acanthamoeba, stock H-1, isolated from a patient with keratitis (Krankenhaus Heidberg, Hamburg) was compared with that of two strains of A. quina-A. lugdunensis (302-2, 312-1), two stocks of A. lenticulata (45, 89-1) and one strain of A. rhysodes (302-1). The isolated stock showed glucose-6-phosphate dehydrogenase (G-6-PDH), beta-hydroxybutyric dehydrogenase (beta-HBDH), alcohol dehydrogenase (ADH) and superoxide dismutase (SOD) isoenzyme patterns similar to those of A. quina-A. lugdunensis but their acid phosphatase (AP) patterns differed. Furthermore, cyst morphology showed that the patient-isolated stock belongs to group II of the taxonomic classification of Acanthamoeba. This stock was not thermophilic and exhibited non-pathogenic properties after its intranasal instillation into NMRI mice, whereas it killed BALB/c mice. Immunofluorescent studies revealed the presence of antibodies against Acanthamoeba in the patient's serum. Immunoblotting experiments showed that a 45-kDa protein reacted with this serum. Such an antigen was also detected in A. quina-A. lugdunensis and A. lenticulata. Lectin reactions with Canavalia ensiformis, Ricinus communis-120, Lotus tetragonolobus, Ulex europaeus I, Helix pomatia, Arachis hypogaea, Triticum vulgaris, Glycine maxima, Bauhinia purpurea and Mycoplasma gallisepticum demonstrated that only the A. lenticulata stocks could not be distinguished and that the H-1 stock was more similar to the A. lugdunensis 302-2 strain than to the other acanthamoebae.

Acanthamoeba↗
PubMed1994

Long-bone osteomyelitis diagnosis and management.

The pathogen may proliferate years after seemingly successful treatment. The authors describe a classification system to evaluate both the disease and the patient's capacity to undergo the rigors of therapy. Two cases illustrate the clinical issues.

Adolescent↗
PubMed2001

[Chromosome replication in mycobacteria].

Variation in growth rate has provided a basis for the broad classification of Mycobacterium: (i) the slow-growing class includes the human pathogens Mycobacterium tuberculosis and M. leprae, and (ii) the fast-growing class includes saprophytic nonpathogens, such as M. smegmatis. An intimate association between DNA chromosomal replication and growth rate have been suggested. However, the molecular basis of this relation is unknown. In this article, we summarise our recent work on the study of the origin replication region of some species of mycobacteria, determination of the factors regulating the initiation of DNA replication and the characterisation of the main factor of the replicative machinery, the DnaA protein.

Bacterial Proteins↗
PubMedDate not supplied

[Secreted pathogenicity factors of enterobacteria].

Data on the secreted pathogenicity factors of different enterobacterial species are reviewed. Update information on toxin classification is presented. The main cytotoxic and cytotonic enterotoxins, transient pore forming toxins (RTX), cytotoxic necrotizing factor and injection toxins have been analyzed. Problems connected with the mechanism of action and genetic control of known enterobacterial toxins are discussed.

Animals↗
PubMed1998

[New classification and diagnostic criteria for diabetes mellitus].

The new Classification and Diagnostic Criteria for Diabetes Mellitus (DM), prepared by a group of experts from the American Diabetes Association is presented and analyzed. On an etiopathogenic basis, it designates Insulin Dependent and Non Insulin Dependent as Type 1 and Type 2 respectively. It specifies DM having specific known causes. It maintains Gestational Diabetes and Glucose Intolerance and adds the Impaired Fasting Glucose Condition. It recommends fasting plasma glucose for search and diagnosis, and lowers the level to > or = 126 mg/dl instead of > or = 140 mg/dl, due to its association with chronical complications of DM. It maintains the diagnostic criteria of random and post charge glycemia > or 200 mg/dl. It does not alter the glucose intolerance figure (140-200 mg/dl in OGTT) and introduces fasting abnormality > or = 110 and < 126 mg/dl. It encourages the search with fasting glucose every 3 years in individuals aged over 45, and at more frequent intervals in younger individuals with high risk factors. Analysis of the report allows to conclude that, although the classification does not introduce any significant change in daily clinical use, its pathogenic orientation makes future innovations possible. The preferential use of fasting glucose > or = 126 mg/dl for diagnosis of DM has theoretical basis and practical advantages. Identification of individuals with impaired fasting glucose allows to detect, in a simple manner, a high risk group in which to start preventive measures. However, there is a percentage of cases which are not diagnosed by fasting glycemia, but are diagnosed by OGTT, therefore the latter should not be discarded.

Blood Glucose↗
PubMed1996

[Molecular biology of enteroviruses].

Molecular biological methods offer new approaches to the study of RNA viruses. On the example of enteroviruses we tried to give an account, of recent progress in the knowledge and understanding of these important human pathogens. Firstly concerning their structural and genomic organisation; secondly as regards understanding of their pathology and pathogenicity; thirdly the impact of such methods on rapid, sensitive and specific diagnosis, treatment, on epidemiology and finally on evolution and classification of the large picornavirus family where the enterovirus genus belongs. We believe that molecular biology will elucidate still unknown features of enteroviruses, which are not yet correctly evaluated human pathogens.

Enterovirus↗
PubMed2026

Molecular clusters and precision medicine in pheochromocytomas and paragangliomas.

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors derived from chromaffin cells of the adrenal medulla and extra-adrenal paraganglia. Over the past two decades, the genomic characterization of PPGLs has profoundly transformed their diagnosis, classification, risk stratification, and therapeutic management. Up to 40% of PPGLs harbor germline pathogenic variants, the highest proportion among human neoplasms, and somatic driver events are identified in a substantial fraction of the remaining cases. Integrative multi-omic studies have established three main molecular clusters: a pseudohypoxic cluster driven by Krebs-cycle alterations (SDHx, FH, MDH2, DLST) and HIF-2&#x3b1; pathway alterations (VHL, EPAS1, EGLN1/2); a kinase-signaling cluster driven by activation of RAS/MAPK and PI3K/AKT pathways (RET, NF1, HRAS, TMEM127, MAX); and a Wnt-signaling cluster characterized primarily by MAML3 fusions. This review summarizes progress in PPGL genomics, highlighting geographic and sex-related particularities. Using EPAS1/HIF-2&#x3b1; and RET as paradigmatic examples, we illustrate how diverse germline, somatic, mosaic, and fusion events converge on common core signaling hubs that can be therapeutically exploited with FDA-approved selective inhibitors for relevant targets (e.g. belzutifan for HIF-2&#x3b1;; selpercatinib and pralsetinib for RET). We further review the genomic determinants of metastatic risk (SDHB, ATRX, TERT, and MAML3 fusions), the immune microenvironment of metastatic disease, and emerging radionuclide theranostics, liquid biopsy biomarkers, and integrative multi-omic approaches that are reshaping precision medicine for PPGLs.

Humans↗
PubMed1993

[Chromobacterium violaceum, opportunist pathogenic bacteria in tropical and subtropical regions].

Chromobacterium violaceum is isolated from soil and waters in tropical and subtropical areas. This Gram negative bacillus is considered as a saprophyte, but occasionally it can act as an opportunistic pathogen for animals and man, and cause fatal septicaemia from skin lesion with many liver and lung abscesses. Classification, nomenclature, media used to isolation, characters useful to identification (morphology, cultural and biochemical traits, violacein pigmentation), differentiation from related violet-pigmented species and from Vibrionaceae (when C. violaceum cultures are not pigmented), antibiotics resistance and susceptibility, experimental and natural pathogenicity are emphasized.

Animals↗
PubMed1995

A definition of advanced types of atherosclerotic lesions and a histological classification of atherosclerosis. A report from the Committee on Vascular Lesions of the Council on Arteriosclerosis, American Heart Association.

This report is the continuation of two earlier reports that defined human arterial intima and precursors of advanced atherosclerotic lesions in humans. This report describes the characteristic components and pathogenic mechanisms of the various advanced atherosclerotic lesions. These, with the earlier definitions of precursor lesions, led to the histological classification of human atherosclerotic lesions found in the second part of this report. The Committee on Vascular Lesions also attempted to correlate the appearance of lesions noted in clinical imaging studies with histological lesion types and corresponding clinical syndromes. In the histological classification, lesions are designated by Roman numerals, which indicate the usual sequence of lesion progression. The initial (type 1) lesion contains enough atherogenic lipoprotein to elicit an increase in macrophages and formation of scattered macrophage foam cells. As in subsequent lesion types, the changes are more marked in locations of arteries with adaptive intimal thickening. (Adaptive thickenings, which are present at constant locations in everyone from birth, do not obstruct the lumen and represent adaptations to local mechanical forces). Type II lesions consist primarily of layers of macrophage foam cells and lipid-laden smooth muscle cells and include lesions grossly designated as fatty streaks. Type III is the intermediate stage between type II and type IV (atheroma, a lesion that is potentially symptom-producing). In addition to the lipid-laden cells of type II, type III lesions contain scattered collections of extracellular lipid droplets and particles that disrupt the coherence of some intimal smooth muscle cells. This extracellular lipid is the immediate precursor of the larger, confluent, and more disruptive core of extracellular lipid that characterizes type IV lesions. Beginning around the fourth decade of life, lesions that usually have a lipid core may also contain thick layers of fibrous connective tissue (type V lesion) and/or fissure, hematoma, and thrombus (type VI lesion). Some type V lesions are largely calcified (type Vb), and some consist mainly of fibrous connective tissue and little or no accumulated lipid or calcium (type Vc).

Aneurysm↗
PubMed1995

A definition of advanced types of atherosclerotic lesions and a histological classification of atherosclerosis. A report from the Committee on Vascular Lesions of the Council on Arteriosclerosis, American Heart Association.

This report is the continuation of two earlier reports that defined human arterial intima and precursors of advanced atherosclerotic lesions in humans. This report describes the characteristic components and pathogenic mechanisms of the various advanced atherosclerotic lesions. These, with the earlier definitions of precursor lesions, led to the histological classification of human atherosclerotic lesions found in the second part of this report. The Committee on Vascular Lesions also attempted to correlate the appearance of lesions noted in clinical imaging studies with histological lesion types and corresponding clinical syndromes. In the histological classification, lesions are designated by Roman numerals, which indicate the usual sequence of lesions progression. The initial (type I) lesion contains enough atherogenic lipoprotein to elicit an increase in macrophages and formation of scattered macrophage foam cells. As in subsequent lesion types, the changes are more marked in locations of arteries with adaptive intimal thickening. (Adaptive thickenings, which are present at constant locations in everyone from birth, do not obstruct the lumen and represent adaptations to local mechanical forces). Type II lesions consist primarily of layers of macrophage foam cells and lipid-laden smooth muscle cells and include lesions grossly designated as fatty streaks. Type III is the intermediate stage between type II and type IV (atheroma, a lesion that is potentially symptom-producing). In addition to the lipid-laden cells of type II, type III lesions contain scattered collections of extracellular lipid droplets and particles that disrupt the coherence of some intimal smooth muscle cells. This extracellular lipid is the immediate precursor of the larger, confluent, and more disruptive core of extracellular lipid that characterizes type IV lesions. Beginning around the fourth decade of life, lesions that usually have a lipid core may also contain thick layers of fibrous connective tissue (type V lesion) and/or fissure, hematoma, and thrombus (type VI lesion). Some type V lesions are largely calcified (type Vb), and some consist mainly of fibrous connective tissue and little or no accumulated lipid or calcium (type Vc).

Aneurysm↗
PubMed1982

Application of flow cytometry to studies of pathogenic free-living amoebae.

Species of small, free-living amoebae of the genera Naegleria and Acanthamoeba can cause fatal amoebic meningoencephalitis. Previous investigations have shown that pathogenic amoebae are associated with thermally altered water. Flow cytometric techniques for identifying species of pathogenic and nonpathogenic amoebae from such water have been developed, using immunofluorescence and fluorescein-bound concanavalin A. Flow cytometry is accomplished with a cytofluorograph, in which cells are dispersed in a suspended carrier liquid and passed in front of a focused argon ion laser beam. Cells are then distinguished by the degree of scattered light (size) or fluorescence. Flow cytometry techniques have proven efficient for environmental samples, as indicated by the identification of pathogenic Naegleria fowleri and nonpathogenic Naegleri gruberi and Acanthamoeba castellanii isolated from the Savannah River Plant in South Carolina. Cytofluorographic analysis of environmental samples has several advantages over the current methods of isolation and classification of free-living amoebae. With this system, it is possible to rapidly identify species and quantitate mixtures of pathogenic amoebae in environmental samples. Cytofluorographic analysis of amoebic isolates reduces the time presently required to screen environmental sites for pathogenic amoebae. The cytofluorograph permits detection and species identification of nonthermophilic Naegleria spp. and Acanthamoeba spp. that could not easily be isolated for species identification by conventional methods. Other advantages of flow cytometry over fluorescent microscopy include a high degree of statistical precision due to the large numbers measured, high immunofluorescent titers, and elimination of subjectivity and fluorescence fading.

Agglutination Tests↗
PubMed1998

Pathology of human immunodeficiency virus infection: infectious conditions.

Infection with the human immunodeficiency virus (HIV) and the subsequent derangement of host immunity place affected patients at risk for secondary infections. Some of the secondary pathogens occur with such frequency or are so rare in the non-immunosuppressed population that they have become part of the Centers for Disease Control and Prevention (CDC) classification for HIV/acquired immune deficiency syndrome (AIDS). Other infectious agents not yet included in the CDC definition are being reported in the HIV-infected population with increased frequency. General observations of the degree of immunosuppression associated with specific secondary infections have been useful in developing classification systems for HIV disease such as that of the CDC. However, the specific alterations in host immunity that promote infection with specific secondary pathogens are generally unknown. Geographic differences in the types and frequency of secondary infections also have been reported. Variation in strains of HIV, effect of malnutrition, lack of appropriate medical treatment, prevalence of virulent infectious diseases, and epidemiologic differences are possible contributing factors. Some infections that seemed likely to be closely associated with HIV infection have not occurred more frequently in HIV-infected patients. This review summarizes the histopathology of infectious conditions in the current CDC classification and highlights some conditions seen in HIV-infected individuals that are not currently HIV/AIDS-defining infections, yet may be seen by practicing pathologists.

AIDS-Related Opportunistic Infections↗
PubMed1993

[Problems of food hygiene with carriers of microorganisms and permanent excretors].

To appraise the significance of chronic excretors and carriers for the development of "food poisoning", the analysis must also include the food. First of all, the question arises as to whether foods only have a vector function or whether an increase in the bacterial count is an important prerequisite for the elicitation of human disease. When pure intoxication pathogens are not involved, this question arises in connection with the minimum infectious dose. A classification of the most important causative organisms of bacterial foodborne infections and intoxications is presented in the light of these considerations. If foods only have a vector function, hygiene measures are automatically concentrated on excretors in order to prevent the bacteria from passing into foods. When this is not the case (as in the vast majority of human foodborne infections and intoxications of bacterial origin), two strategies can be successfully applied. First of all, precautions must be taken to rule out bacterial contamination. On the other hand, an increase in the bacterial count, i.e. proliferation of the pathogens in the food must be prevented by appropriate measures. The interacting factors are described. The example of salmonellae is cited to illustrate the routes of contamination from excretors (humans and animals) to foods ready for consumption and possible hygiene measures.

Animals↗