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PubMed1994

A comparison of delusional and nondelusional body dysmorphic disorder in 100 cases.

A controversial issue that was debated for DSM-IV is whether body dysmorphic disorder (BDD)--a preoccupation with an imagined defect in appearance--can be psychotic. BDD is classified separately from its delusional counterpart (delusional disorder, somatic type) in DSM-IV, but does it have a psychotic variant that overlaps with, and may even be the same diagnostic entity as, its delusional disorder variant? One hundred consecutive patients with DSM-III-R-defined BDD or its delusional variant were assessed with a semistructured interview, the Structured Clinical Inverview for DSM-III-R, and a modified version of the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). The 48 patients with nondelusional BDD were compared with the 52 patients with delusional BDD (i.e., delusional disorder, somatic type). The two groups did not differ significantly in terms of most variables examined, including demographics, phenomenology, course, associated features, comorbidity, and treatment response. Thus, BDD may have a psychotic subtype that significantly overlaps with, and may even be the same disorder as, its delusional disorder variant. However, delusional subjects had higher total scores on the modified Y-BOCS, suggesting that the delusional variant of BDD may be a more severe form of the disorder. Although preliminary, these findings have implications for BDD's treatment and classification, suggesting that inclusion of a delusional (psychotic) subtype of BDD should be considered for future editions of DSM.

Adolescent↗

PubMed1975

Identification of Chromobacterium violaceum: pigmented and non-pigmented strains.

The classification and, therefore, identification of Chromobacterium violaceum has been based upon its ability to produce a violet pigment. Although the organism may yield non-pigmented variants when subcultured on artificial media, the isolation of non-pigmented strains from pathological tissues or from nature had not been reported. With a method established for the identification of C. violaceum regardless of violet pigmentation, non-pigmented strains were isolated from nature. The presence of non-pigmented strains of C. violaceum in nature is of significance to taxonomy and clinical bacteriology. Pigmentation cannot be held as an essential characteristic of the definition of the genus Chromobacterium and gives credence to the suspicion of Sneath (1960, 1966) that the genus is not a natural one. Non-pigmented strains may have been isolated from clinical material but wrongly identified as belonging to other genera of non-pigmented Gram-negative bacilli and regarded as not being pathogenic.

Animal Diseases↗

PubMed1988

Reconsideration of the classification of the neuronal ceroid-lipofuscinoses.

Neuronal ceroid-lipofuscinoses (NCL) represent diseases of different types. Each variety of NCL may have its own clinical course, genetics, pathogenesis, and treatment. Four disorders are presently accepted as examples of NCL. These include the chronic juvenile or Batten type, the acute late infantile or Bielschowsky type, the chronic or subacute adult Kufs type, and the acute infantile or Santavuori-Haltia type. Seventy patients with clinical and pathological features of NCL have been studied over 20 years; 62 of these fit into one of the above categories, but 8 are atypical and present nosologic problems. Recognized as examples of atypical NCL are 1) chronic congenital or Norman-Wood type, 2) acute adult or Zeman-Dyken type, 3) acute childhood or Bielschowsky variant, 4) chronic childhood (Edathodu-Dyken) type, with pervasiveness, 5) chronic infantile (Dyken) type with autism, and 6) chronic juvenile (Dyken) type with ataxia. It is proposed that our present classification of NCL be based on differentiating clinical dynamics and characteristics, age-of-onset, and morphological and pathological criteria. Although genetic characteristics are now recognized, these are of autosomal recessive or autosomal dominant type. No differentiating biochemical differences have been established to aid in the nosology of these diseases.

Adult↗

PubMed2026

Genome-Wide and Rare Variant Association Studies of Amblyopia in Admixed American and African Ancestry Groups.

OBJECTIVE: To identify genetic variants associated with amblyopia in African (AFR) and Admixed American (AMR) ancestry groups, expanding on previous studies conducted in European ancestry. DESIGN: Retrospective ancestry-stratified genome-wide association study (GWAS) and gene-level rare variant association study (RVAS). PARTICIPANTS: Participants in the All of Us Research Program from AFR and AMR ancestry groups who had whole-genome sequencing available. Cases and controls were distinguished based on the presence of International Classification of Diseases 9/10/SNOMED diagnosis codes for amblyopia in electronic health records. This yielded ancestry-stratified subsets of 269 cases and 71 585 controls of AMR ancestry and 366 cases and 79 460 controls of AFR ancestry. METHODS: Stratified logistic regression models were adjusted for age, biological sex, and the top 10 principal components of genomic ancestry. GWAS was limited to common variants (minor allele frequency ≥1%), and RVAS was limited to rare variants with coding sequence-altering effects (minor allele frequency >1%, exonic only, excluding synonymous variants) aggregated at the gene level using the SKAT algorithm. Downstream analyses of the significant variants were performed using KEGG and GO pathway analysis and STRING database queries for protein-protein interactions and gene-gene interactions. MAIN OUTCOME MEASURES: Single-nucleotide polymorphisms were determined to have genome-wide significance if P < 5e-8 in the GWAS, and genes were determined to have significant association with amblyopia in the RVAS if P < 8.0 × 10-4. RESULTS: In the AMR GWAS, 245 unique single-nucleotide polymorphisms mapping to 97 distinct loci were identified, notably within neurodevelopmental and axonal guidance genes, including ROBO1, SEMA4B, PTPRD, NRXN1, and CAMK2D. The AFR GWAS identified 11 significant variants corresponding to 6 loci mapping primarily to long noncoding RNAs and pseudogenes. The AMR RVAS identified 15 genes, including axonal transport genes (KIF1B and KIF7) and growth factor signaling genes (EGF, ERBIN, and AKAP17A). The AFR RVAS identified a single gene, DLG2, which encodes the postsynaptic protein PSD-93, which promotes the closure of the sensitive period of neuroplasticity for vision in early childhood. CONCLUSIONS: Genetic risk architectures for amblyopia differ across ancestries but fundamentally converge on neurodevelopmental signaling, cortical synapse assembly, and sensitive period plasticity rather than ocular structural dynamics. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.

Amblyopia↗

PubMed1986

[Prognostication of individual radiation sensitivity of animals, based on the use of a mathematical method of object classification].

A statistical method of object classification based on the use of linear discriminant analysis, was employed to solve the problem of prediction of the outcome of acute radiation disease. In experiments on 23 monkeys irradiated at a dose of 5.3 Gy 14 animals had survived and 9 perished. The initial state and early response (in 5 h) to gamma-beam radiation were assessed. The total number of the analyzed parameters was 16. According to the experimental results an integral index--discriminator--was computed for each object. Values for the survivors ranged within 136.1-151.3, and for 9 more radiosensitive animals the values of discriminators turned out to be higher (151.9-168.7). The procedure of prognosis was the following. 23 monkeys were randomly divided into 2 groups (using the table of random numbers). The 1st group (a study sample) included 13 animals, of them 8 survived and 5 perished. The 2nd group (a control predictor sample) included 10 animals, of them 6 survived and 4 perished by the end of the experiment. The authors described 3 variants of a random selection of the animals both for the 1st and 2nd groups. The results of prognosis were compared with the experimental results. Erroneous prognosis for each variant was 10, 0 and 20%, respectively.

Algorithms↗

PubMed1982

The electron microscopical and physical characteristics of small round human fecal viruses: an interim scheme for classification.

Many of the small round human fecal viruses implicated in outbreaks of nonbacterial gastroenteritis have been collected together and examined under the electron microscope. Negatively stained preparations without the addition of antibody were used so that the surface morphology of the virus particles remained clearly visible. It was apparent that several viruses, previously thought to be simply antigenic variants within the Norwalk group of viruses, show distinct morphological differences and quite clearly belong to other virus groups. By comparing the features of all the viruses examined in this study, both with each other and with standard cell culture strains of enterovirus, parvovirus, and calicivirus, it has been possible to propose an interim classification scheme, based primarily on the morphological appearance of the particles and supported by estimations of size and buoyant density.

Caliciviridae↗

PubMed2002

Autoimmune cholangitis: not just AMA-negative primary biliary cirrhosis.

Variant forms of chronic cholestatic liver disease in adults, such as autoimmune cholangitis, primary biliary cirrhosis-autoimmune hepatitis overlap, and primary sclerosing cholangitis-autoimmune hepatitis overlap constitute approximately 20% of cases of autoimmune liver disease. Retrospective study design may obscure subtle differences in clinical features. Careful prospective studies are needed to help clarify classification of these disorders. Autoimmune cholangitis is often considered synonymous with antimitochondrial antibody-negative primary biliary cirrhosis, but may instead be a heterogeneous group of disorders including some cases of isolated small duct primary sclerosing cholangitis. The variable response of variant syndromes to established therapies such as corticosteroids provides justification for continued efforts to define their clinicopathologic features.

Comment↗

PubMed1989

Normal and anomalous coronary arteries: definitions and classification.

Results of a comprehensive survey of the literature concerning coronary artery anatomy, embryology, and pathophysiology show the lack of an adequate definition of normal coronary arteries. To fill this gap, the present review considers the available data concerning the embryogenesis of the coronary arteries and proposes a new definition of normality that refers to essential anatomic features. The concepts of normal variant versus anomaly are introduced, based on a statistical definition of the normal range (99% of the presentations observed in a normal, unselected population). Coronary anomalies are defined as those patterns found in less than 1% of the cases. The wide spectrum of coronary abnormalities is then organized according to a comprehensive classification scheme. For clinical purposes the conceptual difference between anatomic and pathophysiologic anomalies is stressed. The current paucity of experimental studies concerning normal and abnormal embryogenesis of the coronary arteries is found to be the major limitation to an understanding of this subject.

Coronary Vessel Anomalies↗

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↗

PubMed1991

Cystic renal neoplasms of infancy and childhood: a light microscopical, lectin histochemical and immunohistochemical study.

Cystic renal neoplasms of infancy and childhood, represented largely by cystic variants of nephroblastoma, form a spectrum of clinicopathological entities with differing behaviours. Cystic nephroma and cystic partially differentiated nephroblastoma occupy the benign end of the tumour spectrum, while polycystic Wilms' tumour forms the malignant end. A wide variety of names, reflecting different theories on aetiology, has been applied to the lesions comprising this spectrum, and this has undoubtedly caused confusion in their recognition and classification. We examined five cases of cystic renal tumours in young children which illustrate the entire spectrum, and lectin histochemical and immunohistochemical analysis of these cases showed a close similarity in the pattern of staining of the three variants of cystic tumours. This finding, which has not previously been reported to our knowledge, supports the concept of a close pathogenetic relationship between these tumours.

Biomarkers↗

PubMed1983

Classification of Na channel receptors specific for various scorpion toxins.

1. The specific binding to rat brain synaptosomes of a radiolabelled derivative of toxin II from the scorpion Centruroides suffusus suffusus could be prevented by toxins III and IV, but not by toxin V or variants 1-3, from the venom of Centruroides sculpturatus. 2. The specific binding of a similar derivative of toxin II from Androctonus australis Hector was not affected by any of the toxins from Centruroides sculpturatus. 3. There is biochemical evidence for only two distinct classes of Na channel receptors specific for known scorpion toxins.

Animals↗

PubMed2006

Comparison of the immunophenotypes of signet-ring cell carcinoma, solid adenocarcinoma with mucin production, and mucinous bronchioloalveolar carcinoma of the lung characterized by the presence of cytoplasmic mucin.

The latest World Health Organization (WHO) classification divides adenocarcinoma mainly into adenocarcinoma mixed subtypes, acinar adenocarcinoma, papillary adenocarcinoma, bronchioloalveolar carcinoma, and solid adenocarcinoma with mucin production, and it mentions several variants, including fetal adenocarcinoma, mucinous ("colloid") adenocarcinoma, mucinous cystadenocarcinoma, signet-ring adenocarcinoma, and clear cell adenocarcinoma. In general, the mucin-producing adenocarcinoma of the lung comprises signet-ring cell carcinoma (SRCC), solid adenocarcinoma with mucin production (SA), and mucinous bronchioloalveolar carcinoma (m-BAC), mucinous ("colloid") adenocarcinomas and/or mucinous cystadenocarcinoma, and mucoepidermoid carcinoma. As SRCC, SA, and m-BAC exhibit distinct clinical features, it is important to identify differences in their immunohistochemical characteristics to better understand their histogenesis. In this study we analysed SRCC, SA, m-BAC, normal lung, and foregut-related secretory tissue for immunohistochemical differences using tissue microarrays. SRCC and SA showed high expression of MUC1 (97.4% and 100%, respectively), cytokeratin (CK) 7 (both 100%), and thyroid transcription factor-1 (TTF-1) (81.1% and 100%, respectively). They also showed low expression of MUC5AC (25.5% and 21.1%, respectively) and MUC6 (18.3% and 10.5%, respectively), whereas m-BAC showed high expression of MUC5AC (97.5%), MUC6 (75.0%), and CK7 (94.7%), but low expression of MUC1 (57.5%), and TTF-1 (27.5%). Hierarchical clustering showed that the immunophenotypes of SRCC and SA belong to the same category as alveolar lining cells, whereas m-BAC clustered onto another branch with gastric foveolar cells and bronchial goblet cells. These immunohistochemical findings support the results of our previous clinicopathological analysis of SRCC of the lung showing that SRCC occurs anatomically in the peripheral portion of the lung rather than in the bronchial gland-bearing portion.

Adenocarcinoma↗

PubMed1991

Calcifying odontogenic cyst. A review of ninety-two cases with reevaluation of their nature as cysts or neoplasms, the nature of ghost cells, and subclassification.

Ninety-two cases of calcifying odontogenic cyst (COC) were reviewed with special consideration of their nature as cysts or neoplasms, the nature of ghost cells, and classification on the basis of clinicopathologic features. The cases were divided into 79 (85.9%) cysts and 13 (14.1%) neoplasms. The cysts occurred as four variants: (1) nonproliferative COC (35 cases), characterized by a simple unicystic structure; (2) proliferative COC (17 cases), characterized by a cystic structure with multiple daughter cysts, extensive ghost cell formations, and marked tendency for calcification; (3) ameloblastomatous COC (11 cases), characterized by ameloblastoma-like, cyst-lining epithelium with ghost cells and calcifications; and (4) COC associated with odontoma (16 cases), which combined features of COC and odontoma. The neoplasms occurred as three variants: (1) ameloblastoma ex COC (two cases), which showed unifocal and multifocal intraluminal and intramural ameloblastoma proliferating from the COC-lining epithelium; (2) peripheral epithelial odontogenic ghost cell tumor (eight cases), which occurred in the gingiva and resembled peripheral ameloblastoma except for clustered ghost cells in the central portion of epithelial islands and the presence of juxtaepithelial dentinoid; and (3) central epithelial odontogenic ghost cell tumor (three cases). The latter showed ameloblastomatous or adenomatoid odontogenic tumor-like epithelial clusters with ghost cell formation and juxtaepithelial dentinoid. The clinical features of cystic and neoplastic variants were tabulated and described. On the basis of histopathologic features and their immunohistochemical reaction to polyclonal antikeratin antibody, it is suggested that ghost cells might be the result of coagulative necrosis.

Adolescent↗

PubMed2006

Towards a valid nosography and psychopathology of catatonia in children and adolescents.

Paraphrasing Taylor and Fink (2003), catatonia needs "a home of its own" in child and adolescent psychiatry. Limited but expanding literature supports that catatonia in children and adolescent can be identified reliably among other childhood conditions, is sufficiently common, treatable with the same specific treatments as adult catatonia (e.g., sedative drugs and electroconvulsive therapy), and can be worsened by other treatments (e.g., antipsychotics). Other findings in child and adolescent catatonia suggest that sex ratio and associated disorders may differ, and the proposed classification of Taylor and Fink (2003) needs modification. Adopting a broader diagnostic schedule may accommodate both child, adolescent, and adult catatonia. A psychomotor automatism variant should be included as a diagnosis, as well as specifiers for associated disorders such as acute nonpsychotic anxious state and pervasive developmental disorder. Duration of illness should be specified as acute or chronic. Regardless of associated psychiatric disorders, this chapter describes a new psychopathological model. Three main modalities of movement dysfunction in catatonic subjects are listed: (1) adherence to delusional ideas leading to a psychomotor automatism (De Clérambault, 1927); (2) resistance to delusional thinking or conviction; and finally (3) hyperanxious states. Case-vignettes illustrate the model, and future research directions are identified.

Adolescent↗

PubMed2000

The expanding superfamily of phospholipase A(2) enzymes: classification and characterization.

The phospholipase A(2) (PLA(2)) superfamily consists of a broad range of enzymes defined by their ability to catalyze the hydrolysis of the middle (sn-2) ester bond of substrate phospholipids. The hydrolysis products of this reaction, free fatty acid and lysophospholipid, have many important downstream roles, and are derived from the activity of a diverse and growing superfamily of PLA(2) enzymes. This review updates the classification of the various PLA(2)'s now described in the literature. Four criteria have been employed to classify these proteins into one of the 11 Groups (I-XI) of PLA(2)'s. First, the enzyme must catalyze the hydrolysis of the sn-2 ester bond of a natural phospholipid substrate, such as long fatty acid chain phospholipids, platelet activating factor, or short fatty acid chain oxidized phospholipids. Second, the complete amino acid sequence of the mature protein must be known. Third, each PLA(2) Group should include all of those enzymes that have readily identifiable sequence homology. If more than one homologous PLA(2) gene exists within a species, then each paralog should be assigned a Subgroup letter, as in the case of Groups IVA, IVB, and IVC PLA(2). Homologs from different species should be classified within the same Subgroup wherever such assignments are possible as is the case with zebra fish and human Group IVA PLA(2) orthologs. The current classification scheme does allow for historical exceptions of the highly homologous Groups I, II, V, and X PLA(2)'s. Fourth, catalytically active splice variants of the same gene are classified as the same Group and Subgroup, but distinguished using Arabic numbers, such as for Group VIA-1 PLA(2) and VIA-2 PLA(2)'s. These four criteria have led to the expansion or realignment of Groups VI, VII and VIII, as well as the addition of Group XI PLA(2) from plants.

Animals↗

PubMed2003

Overview of cutaneous T-cell lymphoma: prognostic factors and novel therapeutic approaches.

The cutaneous T-cell lymphomas (CTCL) comprise a heterogeneous group of entities. The WHO classification distinguishes indolent low-risk entities, including mycosis fungoides/Sézary syndrome (MF/SS), from aggressive entities, including peripheral T-cell lymphoma and its variants and HTLV-1 associated acute T-cell leukemia/lymphoma. Mycosis fungoides represents the most benign of the cutaneous T-cell lymphomas, with 10-year relative survival ranging from 100% to 41%, depending on the degree of skin involvement. Probability of progression to extracutaneous disease within 20 years of diagnosis can be up to 40%, depending on stage. Treatment strategies for early stage CTCL include topical therapies with or without interferon-alpha or oral agents, while advanced stage patients often progress and are treated with chemotherapy and novel agents. Multiagent cytotoxic regimens are palliative with no demonstrated survival benefit. Among the novel therapies for CTCL is bexarotene, a retinoid X-receptor (RXR)-selective agonist, which has demonstrated efficacy in advanced refractory CTCL. Other novel agents include the interleukin (IL)-2 fusion toxin (ONTAK), pentostatin (a potent adenosine deaminase inhibitor), histone deacetylase inhibitors such as depsipeptide, NF-kappaB inhibitors, cytokine receptor antagonists, immunomodulatory therapies and allogeneic stem cell therapy. The value of new therapeutic approaches to CTCL urgently needs to be assessed.

Antineoplastic Agents↗

PubMed1992

Flow cytometric DNA analysis of ovarian Brenner tumors and transitional cell carcinomas.

Flow cytometry has been previously used as a method of obtaining prognostic information about ovarian carcinomas using ploidy, DNA index, and S-phase fraction. DNA content has also been assessed in ovarian tumors of low malignant potential. Brenner tumor variants such as metaplastic, proliferating, and low malignant potential, recently designated as intermediate Brenner tumors, and malignant Brenner tumors are unusual tumors that present classification problems. Their histological appearance may not accurately reflect biological activity. We used flow cytometry to analyze paraffin-embedded tissue for DNA content and S-phase in 34 Brenner tumors, three ovarian transitional cell (urothelial) carcinomas (TCCs), and nine normal control ovaries. We correlated histological and clinical features with DNA analysis. Twenty-five Brenner tumors and three ovarian TCCs were acceptable for histogram analysis (coefficient of variation less than 7.0). Thirteen typical, three metaplastic (extensive mucinous or glandular metaplasia), and two proliferating (papillary formation with increased cellularity) Brenner tumors were diploid. One proliferating tumor was tetraploid. The single Brenner tumor of low malignant potential was diploid but had an increased S-phase. Four of five malignant Brenner tumors were aneuploid, and one was diploid. All the TCCs were aneuploid. S-phase was elevated in intermediate and malignant Brenner tumors and TCC. Limited numbers of cases available preclude prognostic prediction based on ploidy in malignant Brenner tumors or primary ovarian TCCs. DNA ploidy and S-phase reflect the intermediate status of metaplastic, proliferating, and low malignant potential Brenner tumors.

Adult↗

PubMed2004

Adult Burkitt leukemia and lymphoma.

The World Health Organization Classification of Lymphoid Neoplasms identifies Burkitt lymphoma/leukemia as a highly aggressive mature B-cell neoplasm consisting of endemic, sporadic, and immunodeficiency-associated variants. These subtypes share many morphologic and immunophenotypic features, but differences exist in their clinical and geographic presentations. All of these subtypes possess chromosomal rearrangements of the c-myc oncogene, the genetic hallmark of Burkitt lymphoma that contributes to lymphomagenesis through alterations in cell cycle regulation, cellular differentiation, apoptosis, cellular adhesion, and metabolism. Brief-duration, high-intensity chemotherapy regimens containing aggressive central nervous system prophylaxis have had remarkable success in the treatment of this disease, with complete remission rates of 75% to 90% and overall survivals reaching 50% to 70% in adults. Although Burkitt lymphoma cells are extremely chemosensitive, biologically targeted therapies should be developed because current treatment options are suboptimal for patients with poor prognostic features or in the setting of relapsed disease.

Adult↗