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PubMed2006

[Gilbert's syndrome: a clinicogenetic trial].

AIM: To improve diagnosis of Gilbert's syndrome (GS) basing on functional and genetic methods of examination. MATERIAL AND METHODS: GS was diagnosed in 88 patients aged 15-72 years using clinical and genetic tests. RESULTS: Genotyping has detected changes in promotor part of the gene coding uridindiphosphateglucuroniltransferase. In homozygous carriers GS was characterized by a higher baseline level of bilirubin, distinct response to functional tests, frequent combination with essential tremor. In heterozygous patients GS often ran latently. CONCLUSION: Four variants of GS course were established: dispepsic, asthenovegetative, jaundice, latent. Low-caloric diet followed by fenobarbital raised sensitivity and specificity of the test. A clinical classification of GS is proposed. The detected disorders of antipirin pharmacokinetics allow prognosis of the risk of unwanted reactions to the drugs metabolized by monooxigenases of the liver.

Adolescent↗
PubMed1977

[Clinical picture of recurring aphthae in the mouth mucosa].

Various classifications of recurrent aphthous ulcers, their differential diagnosis, especially the herpetic ulcers of the oral mucous membranes, are discussed. The clinical and histological pictures show three variants, the minor form, the major form or periadenitis mucosa necrotica recurrens (Sutton), and the herpetiforme aphthous ulcers. Recent investigations discussing the etiology of these ulcers assume that an auto-antigen might be responsible for the immuno-pathological mechanism. This auto-antigen is supposed to be formed by the contamination of the oral mucosa with microorganisms, particularly streptococci.

Adult↗
PubMed2004

Progress in epidermolysis bullosa: genetic classification and clinical implications.

Epidermolysis bullosa (EB), a heterogenous group of genodermatoses, is characterized by fragility and blistering of the skin associated with extracutaneous manifestations. Based on clinical severity, constellation of the phenotypic manifestations, and the level of tissue separation within the cutaneous basement membrane zone (BMZ), EB has been divided into distinct subcategories. Traditionally, these include the simplex, junctional, and dystrophic forms of EB, and recently attention has been drawn to hemidesmosomal variants demonstrating tissue separation at the level of the hemidesmosomes. Specific mutations in ten distinct genes expressed within the cutaneous BMZ have been delineated in >500 families with different variants of EB. The types of mutations, their positions along the affected genes, and their consequences at the mRNA and protein levels provide explanation for the phenotypic variability and genetic heterogeneity of this group of genodermatoses. Elucidation of mutations in different forms of EB has direct translational applications for improved diagnosis and molecularly based classification with prognostic implications as well as for genetic counseling and DNA-based prenatal testing in families with EB.

Basement Membrane↗
PubMed1984

Interpretation of measured red cell mass and plasma volume in males with elevated venous PCV values.

A method of interpretation of red cell mass (RCM) and plasma volume (PV) data is described. The results in 188 males with PCV's over 0.50 places the patients in 4 groups: true (absolute) polycythemias, relative (low plasma volume) polycythemias, high normal red cell mass (HNRCM) and 'physiological variant'. Absolute polycythemias were increasingly frequent at higher PCV levels but only reached 100% at a PCV of 0.60. They showed an 18% incidence in the lower PCV range of 0.500-0.519. Relative (low PV) polycythaemia was found in 18% of the patients with PCV values in the range 0.500 to 0.599. Although the HNRCM and 'physiological variant' types found mainly in the lower PCV ranges they occurred at the 0.54 level. While this method of interpretation of RCM and PV data is perhaps arbitrary, it does provide a basis for the proper study of the common group of patients with raised PCV levels in which classification, course and treatment are uncertain. In addition the findings suggest that both RCM and PV should be measured at all levels of PCV over 0.50; that relative (low PV) polycythaemia is a real entity but less common than sometimes believed; that diuretics do not have a notable part in its causation and that the common HNRCM, 'physiological variant' groups are incompletely understood and require further study.

Diuretics↗
PubMed2006

[Neurological manifestations of type 1 Gaucher's disease: Is a revision of disease classification needed?].

INTRODUCTION: Gaucher's disease (GD), the most prevalent inherited lysosomal storage disorder, is caused by deficient glucocerebrosidase activity. The resulting accumulation of glucocerebrosides in lysosomes of macrophages leads to hepatosplenomegaly, anemia, thrombocytopenia, and various bone manifestations. Gaucher's disease is classified into 3 types based on the nature of its effects on the central nervous system. Type 1, the most common variant, is classically nonneuronopathic. However, the occurrence of Parkinsonism seems to be more frequent in type I Gaucher's disease than in the general population. Furthermore, heterozygotes for certain glucocerebrosidase gene mutations have a higher risk to develop Parkinson's disease. OBSERVATIONS: We report our experience about 9 patients with Gaucher's disease and their association with neurological manifestations. CONCLUSION: These recent data may discuss Gaucher's classification and the existence of a continuum between neurologic and non-neurologic forms of the disease.

Adult↗
PubMed1999

Combined 5 x 2 cv F test for comparing supervised classification learning algorithms.

Dietterich (1998) reviews five statistical tests and proposes the 5 x 2 cv t test for determining whether there is a significant difference between the error rates of two classifiers. In our experiments, we noticed that the 5 x 2 cv t test result may vary depending on factors that should not affect the test, and we propose a variant, the combined 5 x 2 cv F test, that combines multiple statistics to get a more robust test. Simulation results show that this combined version of the test has lower type I error and higher power than 5 x 2 cv proper.

Algorithms↗
PubMed1986

Surface marker analysis in acute myeloid leukaemia and correlation with FAB classification.

The immunological phenotype of blast cells in 102 patients with acute myeloid leukaemia (AML) was analysed with a panel of 20 monoclonal antibodies and the enzyme terminal transferase, and correlated with the FAB classification. Although a partial correlation between these two approaches could be observed, almost every morphological group contained patients from more than one immunological phenotype. The M1 and M5a leukaemias showed the most undifferentiated phenotype, often lacking in specific myelomonocytic antigens. The M3 formed a uniform group defined as My7+, Ia-, FMC8+, a phenotype which was also observed in two cases of the microgranular variant. The granulocytic (CDw15) and monocytic (CDw14) antibodies crossreacted with some M5b and M2 leukaemias, respectively. Compared with M5a, the M5b leukaemias showed a large increase in the expression of CDw14 antigen, confirming the validity of the morphological differentiation. Glycophorin-A was present in four out of five M6 leukaemias. TdT activity was demonstrated in 10% of AML cases, with a higher incidence among the monocytic variants: M4 and M5-. Eleven AML were considered as unclassifiable according to the FAB criteria and in seven of them a megakaryoblastic cell population (GP IIb/IIIa+, GPIb+) was demonstrated; this confirms the need to include the subgroup of megakaryoblastic leukaemias within the AML. Finally, a possible immunological classification for AML is proposed.

Adult↗
PubMed2007

[Burkitt's and Burkitt-like lymphoma. Molecular definition and value of the World Health Organisation's diagnostic criteria].

Among aggressive mature B-cell lymphomas, a reproducible morphological and immunohistological distinction between Burkitt's lymphoma and diffuse large B-cell lymphoma (centroblastic variant) is impossible in a substantial number of cases. The German reference centres for hematopathology collected 220 retrospective cases of aggressive mature B-cell lymphoma whose classification according to the current World Health Organisation criteria was reviewed. Gene expression analysis (Affymetrix) was performed in all cases and chromosomal translocations were determined using fluorescence in situ hybridization. Chromosomal losses and gains were analysed by matrix comparative genomic hybridisation and clinical data were successfully collected for most patients. The application of a novel bioinformatics method led to the identification of a stable and reproducible gene expression signature specific for Burkitt's lymphoma. A total of 44 cases were identified by this molecular signature [designated molecular Burkitt's lymphoma (mBL)]. These molecular Burkitt's lymphomas showed the morphology and immunohistology of classical or atypical Burkitt's lymphoma cases in 29 instances. However, 15 of the molecular Burkitt's lymphoma cases had the morphology of diffuse large B-cell lymphoma or could not be further specified. All molecular Burkitt's lymphomas showed an expression of BCL-6 and CD10, but a MYC translocation was not demonstrable in more than 10% of cases. Of significance is that more than 20% of the molecular Burkitt's lymphomas expressed BCL-2, although weakly in most instances. Our data demonstrate that: (1) the morphological, immunophenotypical and genetic spectrum of Burkitt's lymphoma is broader than previously expected, and (2) our molecular Burkitt's lymphoma signature enables a more precise and extended definition this lymphoma.

Burkitt Lymphoma↗
PubMed2004

Histopathologic classification of lung cancer: Relevance of cytokeratin and TTF-1 immunophenotyping.

Histopathologic classification of lung carcinoma is important, as a prognostic factor and in the evaluation of treatment modalities. Although the World Health Organization classification of lung cancer is based on routine microscopy, immunohistochemistry is an important additional aspect in modern pathologic practice. This study examines whether the main histologic types of lung carcinomas are more reliably diagnosed with immunohistochemical technique using antibodies for the lung tissue-specific antigen thyroid transcription factor-1 (TTF-1) and a panel of cytokeratin (CK) antibodies. Forty-five cases of lung cancer (12 squamous cell carcinoma, 13 small cell carcinoma, 11 adenocarcinoma, 9 large cell carcinoma [LCC]/pleomorphic carcinoma) were stained with antibodies to CK CAM5.2, CK5, CK7, CK20, and TTF-1. All 45 cases were positive with CAM5.2, 16 of 45 cases with CK5, 34 of 45 cases with CK7, 4 of 45 cases with CK20, and 29 of 45 with TTF-1. Squamous cell carcinoma (epidermoid carcinoma) had the immunophenotype CK5+/TTF-1-, and at least 20% were also positive with CK7. Most nonepidermoid tumors had the "lung-specific" phenotype CK5-/TTF-1+; all small cell carcinomas had the phenotype CK5-/CK8+/TTF-1+, all adenocarcinomas CK5-/CK7+/TTF-1+ and (more than 50%) of LCC CK5-/CK7+/TTF-1+. Thus, more than 50% of LCCs were of the same phenotype as adenocarcinomas. The immunophenotypes of the main histologic types of lung carcinoma are stable and highly reproducible. However, because of considerable overlapping, immunophenotyping should not be used alone for histopathologic classification of lung cancer, but only as an adjunct to light microscopy. It is also suggested that CK5+ lung carcinomas with basaloid features should be regarded as variants of squamous cell carcinoma and not as LCC.

Biomarkers, Tumor↗
PubMed2001

Neuronal ceroid lipofuscinoses: classification and diagnosis.

The neuronal ceroid lipofuscinoses (NCLs) are neurodegenerative disorders characterized by accumulation of ceroid lipopigment in lysosomes in various tissues and organs. The childhood forms of the NCLs represent the most common neurogenetic disorders of childhood and are inherited in an autosomal-recessive mode. The adult form of NCL is rare and shows either an autosomal-recessive or autosomal dominant mode of inheritance. Currently, five genes associated with various childhood forms of NCLs, designated CLN1, CLN2, CLN3, CLN5, and CLN8, have been isolated and characterized. Two of these genes, CLN1 and CLN2, encode lysosomal enzymes: palmitoyl protein thioesterase 1 (PPT1) and tripetidyl peptidase 1 (TPP1), respectively. CLN3, CLN5, and CLN8 encode proteins of predicted transmembrane topology, whose function has not been characterized yet. Two other genes, CLN6 and CLN7, have been assigned recently to small chromosomal regions. Gene(s) associated with the adult form of NCLs (CLN4) are at present unknown. This study summarizes the current classification and new diagnostic criteria of NCLs based on clinicopathological, biochemical, and molecular genetic data. Material includes 159 probands with NCL (37 CLNI, 72 classical CLN2, 10 variant LINCL, and 40 CLN3) collected at the New York State Institute for Basic Research in Developmental Disabilities (IBR) as well as a comprehensive review of the literature. The results of our study indicate that although only biochemical and molecular genetic studies allow for definitive diagnosis, ultrastructural studies of the biopsy material are still very useful. Thus, although treatments for NCLs are not available at present, the diagnosis has become better defined.

Adolescent↗
PubMed1997

Cranial osteomas: their classification and management. Report on a giant osteoma and review of the literature.

BACKGROUND: Cranial osteomas are regarded by some as very common; yet their classification, symptomatology, and management have been neglected. METHODS: We report on a giant enostotic convexity osteoma and have reviewed the medical literature. RESULTS: A new comprehensive classification for cranial osteomas is proposed: (1) intraparenchymal, (2) dural, (3) skull base, and (4) skull vault. The latter is in turn, subdivided into exostotic and enostotic variants. Three symptom producing enostotic convexity osteomas have been reported in the world literature. We also describe a giant enostotic skull vault osteoma and propose an original surgical technique used to successfully resect this unusual tumor. CONCLUSIONS: Most cranial osteomas are asymptomatic and need not be resected. Those that are symptomatic should be managed properly. Their excision, if nor properly performed, may lead to unforeseen cerebral complications.

Adult↗
PubMed1996

Second generation hybrid polar compounds are potent inducers of transformed cell differentiation.

Hybrid polar compounds, of which hexamethylenebisacetamide (HMBA) is the prototype, are potent inducers of differentiation of murine erythroleukemia (MEL) cells and a wide variety of other transformed cells. HMBA has been shown to induce differentiation of neoplastic cells in patients, but is not an adequate therapeutic agent because of dose-limiting toxicity. We report on a group of three potent second generation hybrid polar compounds, diethyl bis-(pentamethylene-N,N-dimethylcarboxamide) malonate (EMBA), suberoylanilide hydroxamic acid (SAHA), and m-carboxycinnamic acid bis-hydroxamide (CBHA) with optimal concentrations for inducing MEL cells of 0.4 mM, 2 microM, and 4 microM, respectively, compared to 5 mM for HMBA. All three agents induce accumulation of underphosphorylated pRB; increased levels of p2l protein, a prolongation of the initial G1 phase of the cell cycle; and accumulation of hemoglobin. However, based upon their effective concentrations, the cross-resistance or sensitivity of an HMBA-resistant MEL cell variant, and differences in c-myb expression during induction, these differentiation-inducing hybrid polar compounds can be grouped into two subsets, HMBA/EMBA and SAHA/CBHA. This classification may prove of value in selecting and planning prospective preclinical and clinical studies toward the treatment of cancer by differentiation therapy.

Acetamides↗
PubMed2006

Classification of sporadic Creutzfeldt-Jakob disease revisited.

The sporadic form of Creutzfeldt-Jakob disease (sCJD) has been classified on the basis of the molecular mass of the protease-resistant scrapie prion protein (PrP(Sc)), which can be type 1 or type 2, and the genotype at the methionine (M)/valine (V) polymorphic codon 129, which can be MM, MV or VV. In one classification proposed by Parchi et al., [Parchi P, Giese A, Capellari S, Brown P, Schulz-Schaeffer W, Windl O, Zerr I , Budka H , Kopp N , Piccardo P , Poser S , Rojiani A , Streichemberger N , Julien J , Vital C , Ghetti B , Gambetti P , Kretzschmar H . Classification of sporadic Creutzfeldt-Jakob disease based on molecular and phenotypic analysis of 300 subjects. Ann Neurol 1999; 46: 224-33.] the most common subtype of sCJD, designated sCJDMM1, is viewed as a single entity. Two other classifications proposed by Collinge et al. [Collinge J, Sidle KC, Meads J, Ironside J, Hill AF. Molecular analysis of prion strain variation and the aetiology of 'new variant' CJD. Nature 1996; 383: 685-90.] and Zanusso et al., [Zanusso G, Farinazzo A, Fiorini M, Gelati M, Castagna A, Righetti PG, Rizzuto N, Monaco S . pH-dependent prion protein conformation in classical Creutzfeldt-Jakob disease. J Biol Chem 2001; 276: 40377-80.] respectively, subdivide sCJDMM1 into two subtypes on the basis of the different molecular mass and phenotypic characteristics, primarily disease duration. To resolve this discrepancy, we divided a group of 22 subjects with confirmed sCJDMM1 according to Parchi et al. into two sub-populations according to whether the disease duration was <5 months (short-duration subjects) or >7 months (long-duration subjects). We then examined the PrP(Sc) molecular mass under the conditions that allowed wide variability of the pH of the PrP(Sc) preparations as well as under stringent pH conditions, using high-resolution gel electrophoresis. We also compared the characteristics of the PrP(Sc) associated with the short- and long-duration subjects using two-dimensional immunoblot, conformational stability immunoassay and sucrose gradient fractionation. Finally, the two sub-populations were also compared with regard to their clinical and pathological features including the lesion profiles. When sample homogenization and protease digestion were performed under stringent pH conditions, the PrP(Sc) molecular mass did not differ between short- and long-duration sCJDMM1 subjects. The conformational characteristics of the protease-resistant PrP(Sc) as well as the clinical and pathological phenotypes were also homogeneous except for the more severe lesions of the long-duration cases. We therefore conclude that the variability of the PrP(Sc) molecular mass underlying the division of sCJDMM1 into two subtypes is largely due to pH variations during tissue preparation, and sCJDMM1 with short and long disease duration have similar phenotypes and PrP(Sc) characteristics. These data indicate that the differentiation of sCJDMM1 into two subgroups is not currently justified.

Aged↗
PubMed2006

An update on body dysmorphic disorder.

PURPOSE OF REVIEW: The present review provides an update on current research into body dysmorphic disorder. RECENT FINDINGS: Recent findings can be considered under four groupings: the classification of body dysmorphic disorder, its current inclusion under the somatoform disorders, and its relationship to obsessive compulsive disorder and other obsessive compulsive spectrum disorders; the psychotic 'variant' of body dysmorphic disorder, and whether it is simply a more severe form of the nonpsychotic type; the cognitive aspects of body dysmorphic disorder; and the treatment of body dysmorphic disorder, both in terms of pharmacological and psychological parameters. SUMMARY: Body dysmorphic disorder does not sit comfortably in the somatoform disorder category, and there is a good case for it being considered part of the obsessive compulsive spectrum, although it is not merely a subtype of obsessive compulsive disorder. Insight into the illness suggests that it represents a spectrum of disorders, and a categorical delineation of 'psychotic' and 'nonpsychotic' variants cannot be supported. We are beginning to understand more about the neurocognitive aspects of body dysmorphic disorder, but more research is required to assess which deficits/aberrations (if any) are exclusive to body dysmorphic disorder as an entity, and which are a reflection of broader phenomenological manifestations. Finally, the mainstay of treatment for body dysmorphic disorder remains behaviour/cognitive behaviour therapy and serotonin reuptake inhibitors; much more work is required to identify effective interventions for those patients who fail to respond to these treatment modalities.

Cognition Disorders↗
PubMed1994

Angiodysplastic syndrome with capillary and venous malformation associated with soft tissue hypotrophy.

Angiodysplastic syndromes include a vascular malformation which may often be associated with secondary changes such as further vascular abnormalities, soft tissue and bone hypertrophy. One of the best known is the syndrome triad originally described by Klippel and Trenaunay, which includes a unilateral capillary malformation, ectatic veins and osseous and soft tissue hypertrophy. A female patient is reported who had an extensive capillary malformation, discrete ectatic veins overlying an extensive venous malformation and soft tissue hypotrophy without bone involvement. Our patient and cases from the literature illustrate the occurrence of 'atypical', hypotrophic variants of angiodysplastic syndromes. Discrete superficial angiodysplasias may overlie deep, extensive malformations, and identification of such cases is important with regard to management and prognosis. The current classification of angiodysplasias is based on the primary vascular malformation. The use of eponyms should be avoided, because they do not contribute to the diagnosis and management of such cases.

Adolescent↗
PubMed1979

The limits of Munchausen's syndrome.

The authors review the literature on Munchausen's syndrome and speculate about possible underlying psychological mechanisms. The proposed DSM III classification of factitious illnesses suggests a continuum from hysteria on one end of the spectrum to malingering on the other. Two case studies are presented which represent variants of this syndrome. Both patients were given a sodium amytal interview, a procedure not previously reported in the Munchausen's literature. The procedure was helpful in eliciting a more accurate history and a clearer sense of the underlying dynamics. Some suggestions for further research are made.

Adult↗
PubMed2005

Newly defined central nervous system neoplasms.

In recent years, numerous new entities or variants of recognized central nervous system tumors have been described in the literature, and the morphologic spectrum of these neoplasms is delineated incompletely. The accurate diagnosis and classification of these lesions is important to ensure that patients receive adequate therapy and prognostic information. The clinicopathologic features and differential diagnosis of 4 new entities, including the chordoid glioma of the third ventricle, cerebellar liponeurocytoma, atypical teratoid/rhabdoid tumor, and papillary glioneuronal tumor, are discussed in this review.

Adult↗
PubMed1990

Reviewing the unicystic ameloblastoma: report of two cases.

Classification of ameloblastoma into solid, multicystic, unicystic, and peripheral types based on clinical appearance and effects has gained recent recognition. The unicystic ameloblastoma is a less encountered variant of the ameloblastoma. It appears more frequently in the second or third decade with no sexual or racial predilection. It is almost exclusively encountered asymptomatically in the posterior mandible. The following report of two cases discusses the pathophysiology, demographics, histology, and prognosis of the unicystic ameloblastoma.

Adult↗