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PubMed2002

The immunophenotype of 325 adult acute leukemias: relationship to morphologic and molecular classification and proposal for a minimal screening program highly predictive for lineage discrimination.

Bone marrow cells of 325 adults with acute leukemia were immunophenotyped using a panel of monoclonal antibodies proposed by the European Group for the Immunological Characterization of Leukemias (EGIL). Of these, 97.2% could be assigned clearly to myeloid or lymphoid lineage (254 acute myeloid leukemias [AMLs], 48 B-cell lineage acute lymphoblastic leukemias [ALLs], 14 T-cell lineage ALLs), 1.8% as biphenotypic, and less than 1% as undifferentiated. Immunologic subtyping of ALLs revealed an association between early precursor phenotypes and coexpression of myeloid antigens, particularly CD15/CD65s coexpression and pre-pre-B cell-specific phenotypes and genotypes. The common ALL phenotype was associated with BCR-ABL translocation. Among AMLs, CD2 coexpression was almost exclusively restricted to French-American-British subtypes M3 variant and M4Eo and related molecular aberrations. The most valuable markers to differentiate between myeloperoxidase-negative AML subtypes M0 and ALLs were CD13, CD33, and CD117, typical of M0, and intracytoplasmic CD79a, intracytoplasmic CD3, CD10, and CD2, typical of B cell- or T cell-lineage ALL. Our results confirm excellent practicability of the EGIL proposalfor immunologic classification of acute leukemias. For myeloperoxidase-negative AMLs, we suggest a scoring system based on markers most valuable to distinguish between AML-M0 and ALLs.

Acute Disease↗
PubMed1986

Classification of Histoplasma capsulatum isolates by restriction fragment polymorphisms.

Twenty isolates of the dimorphic, pathogenic fungus Histoplasma capsulatum were divided into three classes based on comparisons of restriction enzyme digests of their mitochondrial DNA and rDNA. The majority of isolates, including most North American strains and the African H. capsulatum var. duboisii variants, belong to class 2. Isolates from Central America and South America make up class 3. The attenuated Downs strain is the only member of class 1.

Africa↗
PubMed1986

The frequency of dominant cataract and recessive specific-locus mutations in mice derived from 80 or 160 mg ethylnitrosourea per kg body weight treated spermatogonia.

A systematic comparison of the frequency of dominant cataract and recessive specific-locus mutations in mice has been extended to include results for 80 and 160 mg ethylnitrosourea per kg body weight spermatogonial treatment. The frequency of confirmed dominant cataract mutations in the historical control, 80 and 160 mg/kg ethylnitrosourea treatment groups was 1/22594, 8/5090 and 14/6435, respectively. The frequency of recessive specific-locus mutations in the same dose groups was, respectively, 19/227805, 20/13274 and 35/8658. These present results confirm previous results, which indicate that ethylnitrosourea is effective in inducing both recessive specific-locus and dominant cataract mutations although the per locus mutation rate to recessive alleles was observed to be approximately 6 times greater than the per locus mutation rate to dominant alleles. The exclusion of certain classes of lens opacity variant phenotypes, previously demonstrated not to be due to a dominant mutation, from the group of suspected dominant cataract mutations subjected to a genetic confirmation test has greatly improved the efficiency of the test. A total of 23 dominant cataract mutations were confirmed from a group of 67 phenotypic variants. Of the 23 confirmed dominant cataract mutations, 8 were shown to have reduced transmission to the following generation of offspring expressing the mutant phenotype. These results are also consistent with previous results for ethylnitrosourea or radiation treatment in which it was shown that approximately one-third of the recovered mutations have reduced penetrance. One group of dominant cataract mutations, with phenotypic effects on the polar, sub-capsular or corneal regions, is overly represented in the group of recovered mutations with a reduced transmission of offspring expressing the mutant phenotype. Two hypotheses are suggested for this observation, both dependent on the fact that the regions affected indicate that the mutations are expressed later in the development of the eye. Either all carrier individuals have not expressed the phenotype at the time of examination and classification, or later acting mutations are more subject to environmental interactions resulting in more variable expression. Finally, it is argued that a dominant cataract mutation test represents a most practicable protocol to screen for induced dominant mutations in germ cells of the mouse. The imposition of the criterion that suspected variants be subjected to a genetic confirmation test has at least two advantages beside the fact that results represent unambiguous mutational events.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1994

Histopathological classification of childhood rhabdomyosarcomas: relationship with clinical parameters and prognosis.

To define a useful and prognostically relevant classification system for rhabdomyosarcomas (RMSs), tissue sections of 113 well-documented, protocol-treated cases were retrieved from the files of the Emma Kinderziekenhuis Amsterdam, the Netherlands, and reclassified by a panel of pediatric pathologists. The following subtypes were recognized: embryonal RMS (n = 66), alveolar RMS (including the solid variant) (n = 16), botryoid RMS (n = 11), embryonal sarcoma (n = 6), and spindle cell RMS (n = 5). Nine cases were classified as RMS not otherwise specified (NOS). The above-mentioned histopathological subtypes correlated significantly with survival (P = .005) in patients with nonparameningeal tumors. Indeed, the best prognosis was observed in patients with spindle cell RMS, embryonal sarcoma, and botryoid RMS (10-year survival rates of 80% to 86%). Patients with embryonal RMS had an intermediate prognosis (10-year survival rate of 55%) and patients with alveolar RMS fared poorly (10-year survival rate of 9%). Survival rate was poor in patients with a localized parameningeal tumor, irrespective of histopathological subtype (10-year survival rate of 33%). Furthermore, this study confirmed the known impact on prognosis of localization (P = .008) and tumor node metastasis (TNM) stage (P = .0005). Classification of RMS subtypes proved to be fairly well reproducible (kappa ranging from 0.47 to 0.85 and percentage of concordance ranging from 50% to 85%). The best agreement was noted in botryoid RMS and the worst in embryonal sarcoma. However, improvement of agreement was noted for the latter subtype during the consecutive classification sessions. In summary, this study shows the strong prognostic value of histopathological subtypes and parameningeal tumor localization.

Child↗
PubMed2003

Analysis of the metal-binding selectivity of the metallochaperone CopZ from Enterococcus hirae by electrospray ionization mass spectrometry.

Metallochaperones are soluble proteins involved in metal transport and regulation in vivo. Copper metallochaperones belong to a structural family of metal binding domains displaying a ferredoxin-like fold (betaalphabetabetaalphabeta) and a consensus metal-binding motif MXCXXC. The metal-binding selectivities for this class of proteins are poorly documented so far. The present study focuses on the measurement of the selectivity of the copper metallochaperone CopZ from Enterococcus hirae for different metal ions using an experimental approach based on electrospray ionization mass spectrometry (ESI-MS). All the metal cations tested, i.e. Cu(I), Cu(II), Hg(II), Cd(II) and Co(II), form specific metal complexes with CopZ. The study of a chemically modified CopZ as well as variants of CopZ in the active site demonstrated that the complexes observed by ESI-MS, i.e. in the gas phase, corresponded to the complexes previously observed by other analytical methods in solution. Competition experiments allowed the classification of the metal ions by increasing affinities for CopZ as follows: Co << Cd < Hg < Cu. A dissociation constant in the range of 20 microM was determined for cobalt. The affinity of CopZ for the other metals tested was found to be higher, with dissociation constants smaller than micromolar.

Bacterial Proteins↗
PubMed1999

[Pathology of childhood and adolescent rhabdomyosarcoma].

Rhabdomyosarcoma (RMS) is the most important and a very heterogeneous group of malignant soft tissue tumors of childhood and adolescence. The two major subtypes (embryonal and alveolar) share a common myogenic differentiation, but seem to be histogenetically not related. The so-called 'International Classification of Rhabdomyosarcoma' includes, besides the two major subtypes, the botryoid and leiomyomatous subtypes of embryonal RMS which are associated with a better prognosis and are treated less aggressively according to current protocols. In addition, the solid variant of alveolar RMS is included in the alveolar group of RMS. The identification of the various subtypes is necessary and important because the treatment with the current protocols is also related to histology. Using conventional stains and immunohistochemistry, these subtypes are distinguishable. Genetic analysis can be helpful in the demonstration of t(2;13) or t(1;13) translocations in alveolar RMS. The identification of alveolar RMS with t(1;13) translocation might become important in the future, because this type of translocation seems to be related to a better prognosis as compared to tumors with a t(2;13) translocation.

Adolescent↗
PubMed1995

Genotyping of Shiga-like toxin genes in non-O157 Escherichia coli strains associated with haemolytic uraemic syndrome.

The pheno- and genotypes of Shiga-like toxins (SLTs) in non-O157 Escherichia coli strains from patients with haemolytic uraemic syndrome were determined. The clinical isolates investigated were from Italy and Germany and belonged to serotypes O22:H8, O26:H-, O26:H11, O91:H-, O111:H- and O128:H-; one isolate was non-typable. SLT genotypes were analysed by complete nucleotide sequence analysis of the B-subunit genes. The results showed that 14 strains possessed slt-I alone, two contained slt-II alone and five isolates harboured both slt-I and slt-II genes. In only two strains were slt-II-related genes found, together with either slt-I or slt-II. These findings indicate that variants of SLT-II are rarely found in non-O157 E. coli isolates from patients with haemolytic uraemic syndrome. Polymerase chain reaction (PCR) with Taq cycle sequencing was found to be a suitable method for classification of slt genotypes.

Bacterial Toxins↗
PubMed2003

The Arabidopsis basic/helix-loop-helix transcription factor family.

The basic/helix-loop-helix (bHLH) proteins are a superfamily of transcription factors that bind as dimers to specific DNA target sites and that have been well characterized in nonplant eukaryotes as important regulatory components in diverse biological processes. Based on evidence that the bHLH protein PIF3 is a direct phytochrome reaction partner in the photoreceptor's signaling network, we have undertaken a comprehensive computational analysis of the Arabidopsis genome sequence databases to define the scope and features of the bHLH family. Using a set of criteria derived from a previously defined consensus motif, we identified 147 bHLH protein-encoding genes, making this one of the largest transcription factor families in Arabidopsis. Phylogenetic analysis of the bHLH domain sequences permits classification of these genes into 21 subfamilies. The evolutionary and potential functional relationships implied by this analysis are supported by other criteria, including the chromosomal distribution of these genes relative to duplicated genome segments, the conservation of variant exon/intron structural patterns, and the predicted DNA binding activities within subfamilies. Considerable diversity in DNA binding site specificity among family members is predicted, and marked divergence in protein sequence outside of the conserved bHLH domain is observed. Together with the established propensity of bHLH factors to engage in varying degrees of homodimerization and heterodimerization, these observations suggest that the Arabidopsis bHLH proteins have the potential to participate in an extensive set of combinatorial interactions, endowing them with the capacity to be involved in the regulation of a multiplicity of transcriptional programs. We provide evidence from yeast two-hybrid and in vitro binding assays that two related phytochrome-interacting members in the Arabidopsis family, PIF3 and PIF4, can form both homodimers and heterodimers and that all three dimeric configurations can bind specifically to the G-box DNA sequence motif CACGTG. These data are consistent, in principle, with the operation of this combinatorial mechanism in Arabidopsis.

Amino Acid Sequence↗
PubMed1963

COLONIAL GROWTH OF ANAEROBIC SPIROCHETES ON SOLID MEDIA.

Hardy, Paul H., Jr. (The Johns Hopkins University School of Medicine, Baltimore, Md.), Young C. Lee, and E. Ellen Nell. Colonial growth of anaerobic spirochetes on solid media. J. Bacteriol. 86:616-626. 1963.-A total of 14 strains of treponemes and one of Borrelia vincentii were cultivated as colonies on agar plates inoculated under ordinary atmospheric conditions, but incubated anaerobically. Every spirochete strain produced diffuse colonies with growth located primarily in the agar; in addition, eight treponeme strains also produced discrete colonies with surface growth. These represented stable colonial variants in several strains, and in one the spirochetes in the surface colonies showed permanently altered cellular morphology. Sufficient variation in colonial morphology was noted between strains to suggest that this may have some value in further classification of this group of microorganisms. Several conditions contributed to the successful growth of all strains as colonies, the most important of which was the use of a firm jelling agar preparation, Ionagar No. 2, that permitted preparation of plates with a final agar concentration of 0.7%. Agar concentrations of 0.9%, or above, in media inhibited treponeme growth.

Agar↗
PubMed2006

Common virulence factors and genetic relationships between O18:K1:H7 Escherichia coli isolates of human and avian origin.

Extraintestinal pathogenic (ExPEC) Escherichia coli strains of serotype O18:K1:H7 are mainly responsible for neonatal meningitis and sepsis in humans and belong to a limited number of closely related clones. The same serotype is also frequently isolated from the extraintestinal lesions of colibacillosis in poultry, but it is not well known to what extent human and avian strains of this particular serotype are related. Twenty-two ExPEC isolates of human origin and 33 isolates of avian origin were compared on the basis of their virulence determinants, lethality for chicks, pulsed-field gel electrophoresis (PFGE) patterns, and classification in the main phylogenetic groups. Both avian and human isolates were lethal for chicks and harbored similar virulence genotypes. A major virulence pattern, identified in 75% of the isolates, was characterized by the presence of F1 variant fimbriae; S fimbriae; IbeA; the aerobactin system; and genomic fragments A9, A12, D1, D7, D10, and D11 and by the absence of P fimbriae, F1C fimbriae, Afa adhesin, and CNF1. All but one of the avian and human isolates also belonged to major phylogenetic group B2. However, various subclonal populations could be distinguished by PFGE in relation to animal species and geographical origin. These results demonstrate that very closely related clones can be recovered from extraintestinal infections in humans and chickens and suggest that avian pathogenic E. coli isolates of serotype O18:K1:H7 are potential human pathogens.

Animals↗
PubMed1981

The diagnostic status of homosexuality in DSM-III: a reformulation of the issues.

In 1973 homosexuality per se was removed from the DSM-II classification of mental disorders and replaced by the category Sexual Orientation Disturbance. This represented a compromise between the view that preferential homosexuality is invariably a mental disorder and the view that it is merely a normal sexual variant. While the 1973 DSM-II controversy was highly public, more recently a related but less public controversy involved what became the DSM-III category of Ego-dystonic Homosexuality. The author presents the DSM-III controversy and a reformulation of the issues involved in the diagnostic status of homosexuality. He argues that what is at issue is a value judgment about heterosexuality, rather than a factual dispute about homosexuality.

Arousal↗
PubMed2005

Australian sporadic CJD analysis supports endogenous determinants of molecular-clinical profiles.

OBJECTIVE: To define the protease-resistant prion protein (PrPres) types and associated clinical profiles in Australian patients with sporadic Creutzfeldt-Jakob disease (CJD) to allow comparison with those reported from other continents and concomitantly reaffirm absence of variant CJD (vCJD). METHODS: Reassessment of available clinical and neuropathologic data on patients referred to the Australian National Creutzfeldt-Jakob Disease Registry (ANCJDR) who died between January 1, 1992, and June 30, 2003, was conducted. Molecular classification of PrPres was determined by immunoblot analysis of available frozen brain tissue. Brain homogenate pH and codon 129 genotype on the prion protein gene (PRNP) were established. RESULTS: PrPres patterns in 35 of 37 patients with sporadic CJD conformed to one of three common reported types. Of a range of clinical features assessed, illness duration was the only clinical feature significantly associated with PrPres type. Two patients displayed coexistence of more than one PrP type, with one displaying a novel pattern of three PrPres types in a single brain region. The absence of vCJD was reconfirmed, supported by the lack of the typical PrPres glycoform pattern. CONCLUSIONS: Given Australia's geographic isolation and environmental uniqueness, the general congruity of these results with those reported from other continents suggests that endogenous factors predominantly determine sporadic Creutzfeldt-Jakob disease (CJD) phenotypic subtypes or "strains." These results support a clinicopathologic classification system whereby both PrPres type and codon 129 genotype are utilized to most accurately depict phenotypic subtypes or strains of sporadic CJD.

Adult↗
PubMed2006

Mastocytosis: the great masquerader.

Variants of mastocytosis can present with puzzling cutaneous and systemic symptoms and signs that can result in an erroneous diagnosis of idiopathic urticaria or idiopathic anayphylaxis. The molecular basis of mastocytosis is now better understood, with updated classification based on distinct growth factor and oncogene abnormalities. Elicitation of a full history and careful attention to the skin examination will usually provide the clinician enough information to deduce that the condition is not simply chronic idiopathic urticaria.

Adult↗
PubMed1992

Systemic sclerosis.

Systemic Sclerosis is a multisystemic disease characterized by sclerosis of the skin and visceral organs, vasculopathy (Raynaud's phenomenon) and autoantibodies. The criteria for the classification of the disease requires either proximal scleroderma (major criteria) or the presence of 2 of the 3 minor features namely sclerodactyly, digital pitting scars and bibasilar pulmonary fibrosis. There are 3 subsets of this condition--diffuse variant, limited variant (CREST syndrome) and Overlap Syndrome (where patients have features of other rheumatic diseases). There are localized forms of scleroderma and pseudoscleroderma states. The presenting features of Systemic Sclerosis are usually Raynaud's, skin changes and arthralgia. Systemic complaints like breathlessness, dyspepsia, etc depending on the organ involved may be present. Management starts with patient education regarding the disease, skin care, exercises and regular medical check-up. There is no miracle cure but much can be done to improve the quality of life of the patient. Nifedepine and other drugs may improve Raynaud's phenomenon. Drugs can be used to treat other complications. Various medication have been tested as disease modifying drugs for scleroderma. These include drugs which inhibit collagen like D-penicillamine, colchicine, and immunosupressive drugs like cyclosporin. Ketotifen, a mast cell stabilizer has been reported to be effective in scleroderma. As it is a relatively safe drug, clinical trials are underway.

Age Factors↗
PubMed1985

[Morphology of dysplasia and small cancer of the breast].

The results of histological study of material from sectoral resection of 285 mammary glands (MG) from 265 patients with fibrocystic disease (FCD) are presented. 112 cases of a nonproliferative FCD and 173 cases with different variants and degree of proliferation and atypia of the duct and lobules epithelium are recorded. Slight proliferation is observed in 66 cases, mild in 43 cases, pronounced proliferation corresponding to the atypical hyperplasia according to the WHO classification of MG tumours (1981) is found in 30 cases; ductal and lobular carcinoma in situ is observed in 16 cases. A long-term follow-up showed the invasive MG carcinoma in the preserved part of MG to develop in 3 of 172 FCD cases (1.7%). A frequent combination of the atypical hyperplasia foci with an intraductal and lobular carcinoma in situ, revealed in 60 cases of the MG small carcinoma (from 3 to 10 mm in size) with a focal invasion, is in favour of the morphogenetic link between dysplasia and MG carcinoma. Electron-microscopic examination of a proliferative FCD (12 observations) and invasive carcinoma (15 observations) established an enhancement of the specific ultrastructural differentiation in parallel with an increase of the epithelial proliferation but did not reveal the ultrastructural signs of malignant transformation.

Adult↗
PubMed1988

[Cost estimation as a form of analysis of the rationality of managing the resources of occupational health services].

The cost account to be applied as a method of improving the financial economy of occupational health services is one of the proposals within the social services reform. The considerations should refer to the account of both total and unit costs. There fore the cost account should involve a comparison of total costs of activities with the productivity of occupational health service facilities, which is largely hampered due to deficiencies in the present knowledge on methods and empirical studies. A significant issue is the precise determination of effects whose measures applied in hitherto performed studies were burdened with the element of conventionality and discretionality. A significant obstacle is the correct classification of detailed cost items pursuant to their original places. In the authors' opinion, solution of those problems may contribute to the development of methods for the unit cost account which is essential in the proposed future variants of financial means allocation within the health care services.

Costs and Cost Analysis↗
PubMed1987

Radiologic aspects of lunatomalacia.

A radiological classification of lunatomalacia, based upon the chronological radiologic manifestations in 93 patients is presented. Compression fractures were not seen as the initial event. Fifty-seven per cent of the patients had a short ulna (ulna minus variant). The presence of ulna minus variant was especially observed in the younger patients. In 16 patients suffering from a lunate fracture and in 20 patients with lunate or perilunate luxations, lunatomalacia did not develop. Immobilization as treatment of the disorder resulted in a progressive course in all patients, but one, an 8-year-old girl. The lesion of the lunate was arrested and tended to heal following radial osteotomy in all patients.

Adolescent↗
PubMed1993

Verrucous naevoid and keratotic malignant melanoma: a clinico-pathological study of 20 cases.

Verrucous naevoid malignant melanoma is a recently described variant of malignant melanoma that may be confused both clinically and histologically with benign lesions. This study reports the clinical and pathological features of 20 such cases. These constituted 3.2% of all melanomas diagnosed in the Department of Pathology, Aberdeen University, in the period 1970-1991. They occurred more often on the back and limbs of male patients with a mean age of 57 years. Clinical diagnosis of benign lesions (warty naevi, papillomas, seborrhoeic keratosis and cysts) were made in over 50% of the cases. Eight patients had metastases, seven of whom died of their disease. Microscopically, these lesions exhibited a spectrum of naevoid features such as symmetry, exophytic and papilliferous growth pattern, hyperkeratosis and pseudo-epitheliomatous hyperplasia. The majority, however, showed lateral intra-epidermal spread and were composed of large epithelioid cells exhibiting various degrees of cellular pleomorphism. Histological classification was difficult, as more than 50% of the cases were initially labelled unclassifiable. The marked papilliferous architecture of these lesions made assessment of Breslow depth and Clark levels difficult. Initially, 10% of the cases were histologically diagnosed as benign. It is therefore important for surgical pathologists to recognize this unusual variant of malignant melanoma, as it may be confused both clinically and pathologically with benign lesions.

Adult↗