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PubMed1977

Morphology of colony variants of the rough form of Dermatophilus spp.

A technique is described for the preparation of intact colonies of Dermatophilus and their study under the scanning electron microscope. Using this technique with 38 strains of the organism it is possible to describe for the first time the patterns of colony morphology and to study the relationship of hyphae, cocci and zoospores in situ. Colonies were found to possess both vegetative and aerial hyphae. The various patterns of mycelial activity and structure that were seen raised serious doubts about the previous concepts of the mode of propagation and thus the classification of Dermatophilus within the Actinomycetales.

Actinomycetales↗
PubMed2003

Radio-anatomic study of the pancreatic duct by MR cholangiopancreatography.

To compare the performance of MR-cholangiopancreatography (MRCP) and that of classical anatomy in the depiction of the main pancreatic duct, 50 MRCP examinations were done in patients free of pancreatic disease. Axial and coronal sections 20 mm thick were obtained in a Single Shot Fast Spin Echo (SSFSE) sequence. The following were analyzed: (1) visibility of pancreatic duct structures, (2) form of the main pancreatic duct, (3) various angulations of the duct and (4) diameter of the duct. Anatomic variants were noted. These findings were compared with anatomic and radio-anatomic (ERCP) data in the literature. The main pancreatic duct was visualized in 100% of cases and the accessory pancreatic duct in 61%. The form, diameter and angulations of the various segments of the pancreatic duct were similar to those reported in the literature. These findings are reported in the axial and coronal planes. Comparison with major anatomic classifications was not possible. MRCP enables in vivo anatomic exploration of the main pancreatic duct. Horizontal sections provided new radio-anatomic information. The technique nevertheless remains limited by poor spatial resolution.

Adult↗
PubMed2002

[Human prion diseases].

Prion diseases are rare neurodegenerative transmissible fatal diseases affecting humans and mammals. The causative agent is a novel pathogen termed the prion. Unlike classical infectious agents such as bacteria or viruses, prions lack an independent genome and consist largely of an abnormal form of the host-encoded prion protein. Creutzfeldt-Jakob disease (CJD) is the main representative of human prion diseases that may be sporadic in most cases, hereditary, or acquired. Clinical examination yields only a suspected diagnosis with formal criteria for probable or possible. Definite diagnosis relies on autopsy and neuropathology findings. This is also true for the new variant CJD (vCJD), a previously unknown prion disease of humans that is connected with the same strain of prions as found in bovine spongiform encephalopathy (BSE). The autopsy and handling of laboratory material for histopathological examination requires specific precautionary measures and decontamination. For definite histopathological diagnosis of a human prion disease, immunohistochemical detection of the prion protein deposits is the gold standard. Furthermore, molecular and genetic investigations are necessary for classification because a close correlation could be established between distinct CJD phenotypes, codon 129 genotypes of the prion protein gene, and the prion protein type.

Animals↗
PubMed1983

International Commission for Protection against Environmental Mutagens and Carcinogens. ICPEMC Working Paper 5/6. Perspectives in mutation epidemiology, 6. A 1983 view of sentinel phenotypes.

A sentinel phenotype is a clinical disorder or syndrome that (1) occurs sporadically as a consequence of a single, highly penetrant mutant gene, (2) is a dominant or X-linked trait of considerable frequency and low fitness, and (3) is uniformly expressed and accurately diagnosable with minimal effort at or near birth. Although 1828 autosomal dominant traits are known in human beings, 36 can be considered as candidate sentinel phenotypes, along with 5 X-linked disorders. Based on surveys of malformations in infants and children, 16 additional traits are proposed beyond previous lists. In Hungary, the 24 syndromes or defects with reliable manifestations in newborn infants occur with a frequency of 2.5-3.3 per 10 000 live births. As markers of human mutations, sentinel phenotypes have the advantage of representing germinal mutations that result in significant health problems. There are severe disadvantages that have, to date, prevented the launching of a field demonstration of the value of these phenotypes in mutation epidemiology. Agreement on a list of phenotypes has been delayed by continued recognition of two or more distinct genetic diseases within what was once thought to be a single disorder. For the same reason, most of the candidate sentinel phenotypes have not been assigned unique codes in the International Classification of Diseases. Each of the disorders is so rare and has features that overlap with so many other syndromes that highly trained clinical dysmorphologist and pediatric ophthalmologists would have to be engaged in any study. The sentinel phenotype approach, like other strategies in mutation epidemiology, would encounter problems with linkage among files of data, privacy, and access to sufficiently large populations. In contrast with the approach using multiple protein variants (as in the study of blood from offspring of survivors of the atomic bombs in Hiroshima and Nagasaki), the sentinel phenotype approach would likely be much less expensive and would encounter far fewer false attributions of paternity, but also would require a much larger study population. The best option for the present, in our opinion, is to broaden and sustain critical discussion of the approach. Perhaps the goal should be to plan a field demonstration by involving appropriate clinicians, epidemiologists, and public health officials. A pilot effort underway in Hungary may well give insight to applying the approach in a significantly larger population.

Chromosome Aberrations↗
PubMed2005

The usefulness of immunohistochemical markers in the differential diagnosis of renal neoplasms.

Histologic subtyping of RCC has been shown to be of prognostic value; therefore, it is important to classify malignant epithelial tumors of the kidney correctly and also to differentiate them from benign ones. Overlapping morphologic features of renal tumors sometimes make histologic subtyping difficult. The accurate diagnosis and classification of RCC are based on cytoarchitectural features and require correlation with immunophenotype and cytogenetic characteristics. RCC Ma and CD10, two markers with relative renal specificity, have been used to confirm a diagnosis of suspected RCC and can facilitate the accurate diagnosis of metastatic RCC, in particular, in FNA. Although CCRCC and PRCC share most immunomarkers, CK7 and AMACR expression can be helpful in the differential diagnosis of challenging histologic variants of the two. In addition, E-cadherin aids in the distinction between types 1 and 2 PRCC. Useful markers in the differential diagnosis between ChRCC and CCRCCare CK7, RCC Ma, CD10, VIM, CD117, parvalbumin, and E-cadherin. We propose CK7/CK20/CD15 as a useful primary immunopanel to differentiate ChRCC from ONC reliably.

Adenocarcinoma, Clear Cell↗
PubMed2004

Characterization of streptococci and enterococci associated with septicaemia in broiler parents with a high prevalence of endocarditis.

Increased mortality due to septicaemia, where 29% of the affected birds had developed valvular endocarditis, was observed in a flock of broiler parents affected by myelocytomatosis. Bacterial investigations resulted in isolation of streptococci, the classification of which was unknown according to present taxonomy. Strains were isolated from the liver, spleen, heart and salpinx in clinical cases of septicaemia from the affected flock of Ross broiler parents aged between 26 and 56 weeks. Phenotypic characterization followed by genotypic investigation by ribotyping with HindIII and pulsed-field gel electrophoresis (PFGE) with SmaI demonstrated three ribotypes and six different PFGE profile types, respectively. Ribotype A with variant A1, together with the PFGE profile type represented by the three subtypes Ia, Ib and Ic, dominated the outbreak constituting 85% of the strains investigated, indicating clonality. 16S rRNA sequencing of strains representing this genotype demonstrated the occurrence of a recently described new Streptococcus sp., Streptococcus gallinaceus. Sequence analysis of the other genotypes demonstrated in the outbreak, resulted in identical 16S rRNA sequences to the type strain of Enterococcus faecalis. S. gallinaceus appears to represent a new opportunistic pathogen within the poultry industry.

Animals↗
PubMed1989

Proposals for the classification of chronic (mature) B and T lymphoid leukaemias. French-American-British (FAB) Cooperative Group.

Peripheral blood, bone marrow films, and bone marrow biopsy specimens from 110 patients, well characterised by clinical and laboratory studies, including electron microscopy, were reviewed, to determine proposals for the classification of chronic (mature) B and T cell leukaemias. On the basis of cytology and membrane phenotype the following disorders were defined: (i) B cell type: chronic lymphocytic leukaemia (CLL); CLL of mixed cell type, which includes cases with more than 10% and less than 55% prolymphocytes (CLL/PL), and a less well defined form with pleomorphic lymphocytes but less than 10% prolymphocytes; prolymphocytic leukaemia (PLL); hairy cell leukaemia (HCL); HCL variant; splenic lymphoma with circulating villous lymphocytes; leukaemic phase of non-Hodgkin's lymphoma (follicular lymphoma, intermediate, or mantle zone lymphoma and others); lymphoplasmacytic lymphoma with peripheral blood disease (mostly Waldenström's macroglobulinaemia); and plasma cell leukaemia. (ii) T cell type: T/CLL, which was differentiated from reactive T/lymphocytosis; T/PLL; adult T cell leukaemia/lymphoma; and Sézary's syndrome. The recognition of distinct entities within the B and T cell leukaemias seems to have clinical and epidemiological connotations. It is hoped that these proposals may serve as the basis for further work, discussion, and improved management of patients.

Adult↗
PubMedDate not supplied

Early corneal topography patterns after excimer laser photorefractive keratectomy for myopia.

OBJECTIVES: We defined early patterns of corneal topography following excimer laser photorefractive keratectomy (PRK) with a Summit Apex laser without pretreatment software, investigated changes in patterns over time, and identified factors associated with different topography patterns. METHODS: Fifty-eight eyes of 39 myopic patients were studied. EyeSys videokeratography data were analyzed at 1 week and 1, 2, and 3 months after surgery and were classified using a standardized classification system. RESULTS: At 1 week, 4.3% (n = 2) of corneas showed a homogeneous topography, 0.0% showed a toric-with-axis configuration, 2.2% (n = 1) showed a toric-against-axis configuration, 8.7% (n = 4) showed an irregularly irregular topography, 17.4% (n = 8) showed a keyhole pattern, 23.9% (n = 11) showed a semicircular pattern, 41.3% (n = 19) showed a central island pattern, and 2.2% (n = 1) showed focal topographic variants. From 1 week to 1 month, 78.9% of maps changed; from 1 to 2 months, 33.3% of maps changed; and from 2 to 3 months, 40.0% of maps changed, generally to more regular patterns. The central island pattern, which predominated at 1 week, was not seen at 3 months; most had changed to the keyhole or semicircular pattern. An association was found between the central island pattern and irregularity of reflected rings on the video-image of the cornea (P = .05). CONCLUSIONS: The central island pattern is an early and usually transient topography pattern following PRK. Keyhole and semicircular patterns taken together were the most prevalent in the early postoperative period. In some cases, central islands may be a consequence of corneal epithelial irregularity, and the meridional orientation of the keyhole and semicircular patterns suggests an influence of epithelial healing over time.

Cornea↗
PubMed2000

Classification of a bacterial isolate, from pozol, exhibiting antimicrobial activity against several gram-positive and gram-negative bacteria, yeasts, and molds.

A bacterial isolate, designated CS93, capable of producing a broad-spectrum antimicrobial compound(s) effective against gram-positive and gram-negative bacteria, yeasts, and molds was isolated from pozol, a fermented maize product. This strain was phenotypically similar to another pozol isolate that was previously designated as Agrobacterium azotophilium by other investigators. By using biochemical, phenotypic, and 16S rRNA sequence analysis, both pozol isolates were identified as members of the genus Bacillus, possibly a variant of Bacillus subtilis. While the antimicrobial compound(s) was initially produced only on a solid medium, parameters were identified for production in broth. The compound(s) was heat stable (121 degrees C for 15 min), exhibited activity over a wide pH range (pH 3 to pH 11), and was inactivated by pronase E. The antimicrobial compound(s) was bactericidal and bacteriolytic against Escherichia coli V517, bacteriostatic against Micrococcus luteus, and fungistatic against Saccharomyces cerevisiae. The inhibitory compound(s) could possibly serve as a food biopreservative.

Animals↗
PubMedDate not supplied

Osteogenesis imperfecta.

Osteogenesis imperfecta (OI) is a genetically determined disorder of connective tissue characterized by bone fragility. The disease state encompasses a phenotypically and genotypically heterogeneous group of inherited disorders that result from mutations in the genes that code for type I collagen. The disorder is manifest in tissues in which the principal matrix protein is type I collagen (mainly bone, dentin, sclerae, and ligaments). Musculoskeletal manifestations are variable in severity along a continuum ranging from perinatal lethal forms with crumpled bones to moderate forms with deformity and propensity to fracture to clinically silent forms with subtle osteopenia and no deformity. The differential diagnosis includes other entities with multiple fractures, deformities, and osteopenia. Classification is based on the timing of fractures or on multiple clinical, genetic, and radiologic features. Molecular genetic studies have identified more than 150 mutations of the COL1A1 and COL1A2 genes, which encode for type I procollagen. Various systemic treatments have been attempted; however, these interventions have been ineffective or inconclusive or are still experimental. Gene therapy has the potential to increase the synthesis of type I collagen in mild variants and to correct mutations in severe variants, but there are a great number of technical difficulties to overcome. The goals of treatment of OI are to maximize function, minimize deformity and disability, maintain comfort, achieve relative independence in activities of daily living, and enhance social integration. Attainment of these goals requires a team approach to tailor treatment needs to the severity of the disease and the age of the patient. Nonoperative management is the mainstay of orthopaedic treatment, with the goals of preventing and treating fractures and enhancing locomotion. Operative intervention is indicated for recurrent fractures or deformity that impairs function.

Chromosomes, Human, Pair 17↗
PubMed1995

Acantholytic epidermolysis bullosa.

BACKGROUND: We describe a new variant of inherited epidermolysis bullosa and elucidate the clinical, histologic, and ultrastructural features of this condition. OBSERVATIONS: This form of epidermolysis bullosa displays an autosomal dominant inheritance pattern, is characterized by acral bullae, and histologically demonstrates suprabasal clefting with acantholysis. Ultrastructural findings are nonspecific but reminiscent of those observed in benign familial pemphigus. CONCLUSION: Acantholytic epidermolysis bullosa is a rare but distinct clinicopathologic entity that warrants inclusion in the nosologic classification of epidermolysis bullosa.

Acantholysis↗
PubMed2000

A classification for the interferon-tau.

An attempt has been made to provide a rational organization for the many interferon-tau (IFN-tau) sequences entered in GenBank based on phylogenetic analysis and common amino acid substitutions, which might form the basis for a universal nomenclature scheme. Over the 13 years since these genes were first discovered, large numbers of cDNA and gene sequences have been reported, and there is reason to suspect that representatives of all the major ovine and bovine forms have now been described. The data are consistent with the presence of many genes and also allelic variants in sheep and cattle analogous to what has been observed for the IFN-alpha in the human. Future variants should be easily accommodated into the scheme outlined here. A flexible system of nomenclature, based on that used for HuIFN, is needed to provide a common base for comparison between research done in different laboratories and to assign relative biologic potencies to these molecules.

Animals↗
PubMed2005

Revising the way we conceive and name viruses below the species level: a review of geminivirus taxonomy calls for new standardized isolate descriptors.

Geminivirus taxonomy and nomenclature is increasing in complexity with time, and the growing number of geminivirus sequences deposited in gene banks requires regular taxonomic updates and calls for new descriptors to identify virus isolates unambiguously. Fauquet et al. [1] proposed a system to standardize the names of the viruses, and corresponding guidelines have been followed since, rendering nomenclature much easier. Recently, due to difficulties inherent in species identification, the ICTV Geminiviridae Study Group proposed new species demarcation criteria, the most important of which being an 89% identity threshold between complete DNA-A component nucleotide sequences of begomoviruses. This threshold has been utilised since with general satisfaction. In this paper, we review the status of geminivirus species demarcation and nomenclature for a total of 389 isolates. A small number of corrections have been made to comply with the adopted demarcation criteria but otherwise the classification system has remained robust and therefore we propose to continue using it. However, the large numbers of geminivirus sequences that have become available have led us to recognize the need for a better description of virus isolates. The pairwise comparison distribution below the taxonomic level of species identified two peaks, one at 90-91% identity that may correspond to "strains" and one at 96-98% identity that may correspond to "variants". Guidelines for descriptors for each of these levels are proposed to standardize nomenclature. As a consequence, we have revisited the status of some virus isolates to elevate them to "strains". An updated list of all geminivirus isolates currently available is provided.

DNA, Viral↗
PubMed1989

Non-von Recklinghausen's neurofibromatosis resembling a giant pigmented nevus.

We report the case of a 30-year-old female patient with non-von Recklinghausen's neurofibromatosis. In our opinion it does not fit within a system of classification recently described. Clinically, the abnormality resembled a giant pigmented nevus; however, light- and electron microscopy findings were consistent with those of a neurofibroma. No other symptoms of classic neurofibromatosis or other diseases were present. The family history showed no evidence of neurofibromatosis. To the best of our knowledge this manifestation of non-von Recklinghausen's neurofibromatosis has not been previously described. The cause and the inheritance pattern of this variant are not clear.

Adult↗
PubMed1998

Information processing in schizophrenia and bipolar disorder: a discriminant analysis.

Schizophrenia and bipolar disorder are two distinct categories of mental disorders in the DSM-IV. However, it is often difficult to make a differential diagnosis because of the overlapping symptoms. A potential adjunct in the classification of schizophrenia and bipolar disorder is the application of information processing models, as patients with schizophrenia and possibly those with bipolar disorder have information processing deficits. A study was conducted in which a computerized battery of information processing tasks (called COGLAB) was administered to three participant groups: patients with schizophrenia, patients with bipolar disorder, and normal controls. The tasks included the Mueller-Lyer illusion, reaction time, size estimation, a variant of the Wisconsin Card Sorting Test, backward masking, and Asarnow continuous performance. Discriminant analyses were used to investigate the differences among the three groups. Results indicated that COGLAB correctly classified 75.5% of the cases of schizophrenia and bipolar disorder. The Mueller-Lyer illusion and the number of perseverative errors on the card sort most powerfully discriminated the two groups.

Bipolar Disorder↗
PubMed2006

Mixed lineage leukemia-rearranged childhood pro-B and CD10-negative pre-B acute lymphoblastic leukemia constitute a distinct clinical entity.

PURPOSE: Mixed lineage leukemia (MLL) abnormalities occur in approximately 50% of childhood pro-B acute lymphoblastic leukemia (ALL). However, the incidence and type of MLL rearrangements have not been determined in common ALL (cALL) and CD10+ or CD10- pre-B ALL. EXPERIMENTAL DESIGN: To address this question, we analyzed 29 patients with pro-B ALL, 11 patients with CD10- pre-B ALL, 23 pre-B, and 26 cALL patients with CD10 on 20% to 80%, as well as 136 pre-B and 143 cALL patients with CD10 > or = 80% of blasts. They were all enrolled in four Austrian ALL multicenter trials. Conventional cytogenetics were done to detect 11q23 abnormalities and in parallel the potential involvement of the MLL gene was evaluated with a split apart fluorescence in situ hybridization probe set. RESULTS: We found that 15 of 29 pro-B ALL, 7 of 11 CD10- pre-B ALL, and 1 of 2 French-American-British classification L1 mature B-cell leukemia cases had a MLL rearrangement. However, no 11q23/MLL translocation was identified among the CD10+ pre-B and cALL patients. MLL-rearranged pro-B and CD10- pre-B ALL cases had similar clinical and immunophenotypic (coexpression of CDw65 and CD15) features at initial diagnosis. CONCLUSIONS: The striking similarities between the two CD10- ALL subsets imply that CD10- pre-B ALL variants may represent pro-B ALL cases that maintained the propensity to rearrange and express their immunoglobulin heavy chain rather than actual pre-B ALL forms transformed at this later stage of B-cell differentiation. However, direct experimental data are needed to confirm this observation.

Adolescent↗
PubMedDate not supplied

von Willebrand disease: a laboratory approach.

von Willebrand disease (VWD) is a common inherited bleeding disorder. Accurate diagnosis and classification of VWD is crucial for clinical management. A detailed clinical history, including that of bleeding, is required. A family and drug history are also important. Genetic factors such as blood group, and environmental factors such as stress, trauma, pregnancy and inflammation should also be considered. The age, ethnic group and hormonal status could also affect the von Willebrand factor (VWF) levels. No single test is robust enough to detect all variants of VWD. In view of the heterogeneity of the disease and limitations in assays, a battery of tests should be performed before a final diagnosis can be reached. These include the screening coagulation tests, factor VIII:C assay, VWF antigen assay, assessment of functional VWF which includes VWF ristocetin cofactor assays, VWF collagen binding assay, ristocetin-induced platelet aggregation and VWF multimer analysis. The newer ELISA techniques based on VWF binding with factor VIII glycoprotein (Gp) 1b and cerebrosides have also helped in determining certain unusual forms of VWD. The advent of new systems such as platelet function analysers (PFA), thromboelastography (TEG) and clot signature analysers (CSA), which are designed to assess either the primary platelet function or as a global haemostasis screen, have facilitated and simplified the diagnosis. However, few centres all over the world can perform all these expensive tests to provide a final diagnosis of VWD. We reviewed the laboratory investigations required for a diagnosis of VWD. Apart from congenital VWD, the possibility of acquired VWD should be considered in those with a negative past history of bleeding or in the presence of an underlying disease.

Algorithms↗
PubMed1995

[Jaccoud's arthropathy].

Jaccoud's arthropathy is a variant of deforming arthropathy affecting primarily hands. The author presents literature data and analysis of 28 original cases of valvular disease combined with chronic arthritis. Though these cases were diagnosed as Jaccoud's arthropathy, only one of them met Bywaters' criteria. This female patient is described. Jaccoud's arthropathy is suggested to arise due to connective tissue dysplasia resulting in soft tissue impairment in different rheumatic and nonrheumatic diseases. A working classification and additional criteria for postrheumatic Jaccoud's arthropathy are proposed.

Adult↗