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At least 973 records · Page 54Linked to original sources
PubMed1978

The papillary cystadenoma of minor salivary gland origin.

This article reviews the literature of the papillary cystadenoma of minor salivary gland origin and discusses and attempts to clarify the true nature of these lesions. The criteria for diagnosis are presented, and classification of this lesion based on the Histological Typing of Salivary Gland Tumours (World Health Organization) is suggested. In addition, an interesting variant, which we have called the papillary cystadenoma, mucous-cell type, is presented.

Aged↗
PubMed2001

Cytogenetic-clinicopathologic correlations in rhabdomyosarcoma: a report of five cases.

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children younger than the age of 15 years. Histologically, RMS can be subdivided into two major subtypes; embryonal (E-RMS) and alveolar (A-RMS) rhabdomyosarcoma, with E-RMS being the more common. Although cytogenetic and molecular genetic findings have been reported extensively for RMS, clinicopathologic-genetic correlations among these tumors have not been reported in detail. In this report, we correlate the cytogenetic findings, including fluorescence in situ hybridization and spectral karyotyping, with pathologic findings and outcome for five RMS, including two A-RMS, one E-RMS, one botryoid RMS, and one anaplastic nonclassified RMS (N-RMS). The findings in A-RMS and E-RMS generally were consistent with previous reports; however, gain of chromosome 7 in A-RMS and gain of chromosome 9 segments in E-RMS observed here have seldom been reported in the literature. Importantly, the botryoid RMS had a cytogenetic profile similar to other types of E-RMS. An add(11)(q21) observed in this tumor, together with a t(8;11)(q12 approximately 13;q21) reported previously, indicates that 11q21 rearrangements may be nonrandomly related to botryoid RMS. In addition, the N-RMS expressed a cytogenetic pattern similar to that observed in E-RMS, thus providing genetic evidence that anaplastic N-RMS is a variant of E-RMS. Finally, these cases provide cogent evidence for the diagnostic and prognostic significance of the pathologic-genetic classification of RMS.

Adolescent↗
PubMed2005

Oculomotor nerve schwannoma mimicking ophthalmoplegic migraine.

Ophthalmoplegic migraine (OM) is a rare variant of migraine characterized by recurrent attacks of severe headache followed by oculomotor nerve palsy. The recent revision of the International Headache Classification has reclassified OM from a subtype of migraine, defined as a functional headache, to the neuralgia category. We describe a case of an 11-year-old girl with pathologically confirmed oculomotor nerve schwannoma who had been suffering from symptoms mimicking OM. For five years, she has been under treatment for OM, an initial diagnosis which was corroborated by brain magnetic resonance imaging (MRI). Usually, most OM attacks occur during one period in a lifetime and remit completely. In contrast, however, her attacks became more frequent and were not controlled by medication. After surgery, the frequency of OM attacks was reduced. From this experience, we hypothesize that optic nerve tumor is one condition that can mimic OM, without apparent signs suggestive of intracranial mass. To our knowledge, this is the first report to describe a pathologically confirmed case of oculomotor nerve schwannoma mimicking OM.

Child↗
PubMed1996

Structure, genomic organization, replication and variability of hepatitis C virus.

Hepatitis C virus (HCV) is an enveloped, single-stranded RNA virus that has been classified in the Flaviviridae family. The genome of 9400 nucleotides comprises two non-coding regions in 5' and 3' flanking a large reading frame which codes for a polyprotein of 3000 amino acids; this polyprotein is further cleaved into structural (C, E1, E2) and non-structural (NS1, NS2, NS3, NS4, NS5) proteins. The positive RNA acts as a cap-independent messenger; the transcription is mediated by the NS5 RNA polymerase. After the maturation step, the virion is liberated by budding through the cytoplasmic membrane. As for many other RNA viruses, the HCV genome exhibits a high degree of variability, especially in the E2/NS1, E1, NS3 and NS5b regions. Conversely the 5' non-coding region is highly conserved, at least in part, and can be used for diagnostic purposes by PCR technique. Six genotypes of HCV have already been reported, numbered from 1 to 6 in Simmonds' classification. The same genotype can be divided into subtypes (for instance, genotype 1 comprises three subtypes: 1a, 1b and 1c). Various minor variants of the same strain, called quasispecies, are commonly present in the blood of the same patient. Strains of genotype 1b--which is the most widespread worldwide--are correlated with more severe clinical manifestations, greater viral loads and lower response to interferon treatment. The high variability of the HCV genome contributes greatly to the difficulty of designing potent vaccines.

DNA, Viral↗
PubMed1991

Congenital myopathies.

About forty different congenital myopathies (CM) are defined by clinical and morphological criteria. Classical types like central core disease, centronuclear myopathy, and nemaline/rod myopathy are now well established and recognized as neuromuscular conditions. Clinical subtypes as infantile, juvenile, and adult forms have been recognized in several CM. Not infrequently, different disease-specific morphological features may occur in muscle tissue of the same patient combined. Other CM are marked by aggregates of desmin filaments indicating the importance of recent immunohistochemical techniques. Modern myopathological techniques enabled nosological separation of CM, immunohistochemistry, actually, may usher in a new period of research in and understanding of CM. However, application of molecular genetic and molecular biological methods to CM may clarify still unsolved aspects of gene localisation for which the hereditary nature of many CM is particularly conducive, aspects of heterogeneity versus homogeneity of certain CM or clinical variants, of prenatal diagnosis of CM, of pathogenetic and nosological significance of muscle fiber proteins in CM, and of a new nosological classification of CM.

Child↗
PubMed2001

Molecular aspects of B-cell lymphomas of the gastrointestinal tract.

The B-cell lymphomas of the gastrointestinal (GI) tract have represented a field of extensive research ever since a close association was shown with such chronic inflammatory processes as Helicobacter pylori infection. Evidence suggested that the mucosa-associated lymphoid tissue induced by inflammation and autoimmune processes is the environment that gives rise to the small-cell lymphomas of the GI tract (eg, extranodal marginal zone B-cell lymphoma according to Revised European-American Classification of Lymphoid Neoplasms and the World Health Organization Classification of Neoplastic Diseases of the Hematopoietic and Lymphoid Tissue). The small B-cell lymphoma may then progress to highly malignant variants. The B-cell lymphomas of the GI tract may present a stepwise model for lymphomagenesis and progression. This review covers molecular biology and molecular cytogenetic aspects that lead to new insights into the biology of GI lymphomas and potential prognostic factors.

Cell Transformation, Neoplastic↗
PubMed2000

Prognostic significance of histologic grading compared with subclassification of papillary thyroid carcinoma.

BACKGROUND: Papillary thyroid carcinomas represent a diversity of morphologic subtypes and variants, but to the authors' knowledge the prognostic significance of subclassification is not clear. Therefore, the authors compared the value of histologic classification with a combined assessment of histologic key features such as marked nuclear atypia, tumor necrosis, and vascular invasion (i.e., histologic grade). METHODS: One hundred twenty-eight surgically treated patients with papillary carcinoma > 10 mm were studied. The tumors were subclassified and individual histologic features were examined and compared in univariate and multivariate survival analyses. RESULTS: Of all the cases, 55% were of the usual type, whereas 27% showed complex histologic features with different components present and 18% represented specific subtypes. Tall cell differentiation showed an increased frequency of tumor necrosis and vascular invasion, and tumors with solid areas had an increased occurrence of mitotic figures and vascular invasion. Patients with tall cell tumors tended to have reduced survival (P = 0.074), and two patients with columnar cell features died of the disease. When combined, the group of patients with all tumor subtypes had significantly reduced survival when compared with the remainder of patients (P = 0.034), although the difference was only minor. Histologic grade was highly significant (P = 0.0001) in survival analysis, together with mitotic frequency (P = 0.028), S-phase (P = 0.015), and G(2)M-phase fractions (P = 0.040). In multivariate analysis, tumor dimension (P = 0.019) and histologic grade (P = 0. 008) showed significant and independent prognostic importance, whereas subclassification was not found to be significant. CONCLUSIONS: Subclassification of papillary thyroid carcinomas had only a minor prognostic impact, whereas histologic grade was a strong and independent prognostic marker. The authors recommend that all papillary carcinomas be given a histologic grade based on a combined examination of nuclear atypia, tumor necrosis, and vascular invasion. [See editorial on pages 1766-68, this issue.]

Adult↗
PubMedDate not supplied

[A system of the means of genetic information transfer and the possible routes of viral evolution].

A system of means of genetic information transmission (MGIT) modeling the main features of modes of virus reproduction as well as an algorithmic approach to its construction and means of its schematic representation are proposed. The system may be used as the basis for virus classification including taxonomic categories above the family level and for the study of possible evolution relationships between virus groups. One of the variants of virus macroevolution model is described.

Biological Evolution↗
PubMed1989

[Hospitalization of minors at a psychiatric clinic for adults].

The authors analyzed the case-sheets of 45 minors examined and treated in departments for adults at the Psychiatric Clinic, Medical Faculty Comenius University, Bratislava in 1974-1980. The patients comprised 21 girls and 24 boys. Sixty-two case-sheets were analyzed because of repeated hospital admissions. Forty-three hospitalizations concerned adolescents aged 16-17 years. During the last two years of the observation an increase of enforced hospital admissions associated with suicidal attempts and drug dependence was observed. Suicidal attempts occurred in 23.2% of the cases and were demonstrative, affective and seriously meant according to A. E. Licek's classification. All hospital admissions were necessary, frequently urgent and life saving. Hospitalization of adolescents in departments for adults is not an optimal variant of specialized care of youth.

Adolescent↗
PubMed1987

Problems and pitfalls in the histopathologic diagnosis of gestational trophoblastic lesions.

Proliferative lesions of gestational trophoblast pose problems of interpretation and pitfalls in differential diagnosis. Normally an actively proliferative and invasive tissue, healthy trophoblast shares cytologic features with malignant neoplasms. When trophoblastic hyperplasia accompanies macroscopic villous swelling, a diagnosis of hydatidiform mole (HM) is in order. Exuberant and atypical avillous trophoblast characterizes choriocarcinoma (CCA) and placental site trophoblastic tumor (PSTT). The distinction between them rests on the dimorphic composition of CCA as contrasted with the relative monomorphism of PSTT. Immunohistochemical studies contribute to the latter differential diagnosis. Unfortunately, two common conditions share morphologic features with the major lesions of gestational trophoblast. The hydropic abortus may resemble HM; the banal implantation site in normal early pregnancy and later spontaneous abortion may suggest either CCA or PSTT. Familiarity with the normal and benign variants of chorionic epithelium and thorough tissue sampling may be helpful in difficult cases. Ambiguous lesions that do not conform to conventional classification should be referred for consultation. A few, however, will not fit neatly into diagnostic categories. In such instances, a descriptive report and clear communication with the patient's physician provide the best current approach to clinical follow-up.

Choriocarcinoma↗
PubMedDate not supplied

[Schizoaffective disorder: its nosographic significance].

This paper discusses the nosographic significance of schizoaffective disorder. Follow-up studies, genetic and familial studies, response to treatment studies, and neurobiological data are summarized and analysed. Methodological issues and importance of diagnostic criteria are also examined. Current opinion supports heterogeneity of schizoaffective disorder, among which schizophrenia variants or affective disorder variants. Some patients could present another disease. In that case, they are categorized in the sub-type "other" of the RDC classification for schizoaffective disorder.

Follow-Up Studies↗
PubMed1998

[The characteristics of formulating a diagnosis in diseases of the temporomandibular joint].

Classifications of temporomandibular diseases are discussed and formulations of diagnosis considered. The terms "articular dysfunction", "arthropathy", "arthritis", and "arthrosis" are defined and variants of their usage determined. A notion "arthralgia" is introduced as an individual nosological entity among temporomandibular diseases. The most frequent diagnostic errors are enumerated. The authors emphasize the undesirability of using some obscure terms and of diagnoses formulated as "arthrosis-arthritis" in diseases of the temporomandibular joint.

Adult↗
PubMed2000

Variations of the superficial middle cerebral vein: classification using three-dimensional CT angiography.

BACKGROUND AND PURPOSE: Classification of variations of the superficial middle cerebral vein (SMCV) remains ambiguous. We propose a new classification system based on embryologic development for preoperative examination. METHODS: Three-dimensional CT angiography was used to evaluate 500 SMCVs (in 250 patients). The outflow vessels from the SMCV were classified into seven types on the basis of embryologic development. The 3D CT angiograms in axial stereoscopic and oblique views and multiple intensity projection images were evaluated by the same neurosurgeon on two occasions. Inconsistent interpretations were regarded as equivocal. RESULTS: Three-dimensional CT angiography clearly depicted the SMCV running along the lesser wing or the middle cranial fossa. However, the outflow vessel could not be confirmed as the sphenoparietal, cavernous, or emissary type in 39 (8%) of the sides. SMCVs running in the middle cranial fossa to join the transverse sinus or superior petrosal sinus were accurately identified. SMCVs were present in 456 sides: 62% entered the sphenoparietal sinus or the cavernous sinus and 12% joined the emissary vein. Nine vessels were the superior petrosal type, 10 the basal type, 12 the squamosal type, and 44 the undeveloped type. CONCLUSION: Three-dimensional CT angiography can depict the vessels and their anatomic relationship to the bone structure, allowing identification of the SMCV variant in individual patients. Preoperative planning for skull base surgery requires such information to reduce the invasiveness of the procedure. With the use of our classification system, 3D CT angiography can provide exact and practical information concerning the SMCV.

Adult↗
PubMed1993

Prospective analysis and classification of patients with cystinuria identified in a newborn screening program.

Patients who inherit mutant cystinuria genes excrete high concentrations of cystine, ornithine, arginine, and lysine in the urine. At least three variants of cystinuria can be distinguished in heterozygotes. To determine whether certain combinations of mutant genes are more disadvantageous than others, we analyzed amino acid excretion in families of 17 probands with cystinuria identified by the Quebec neonatal screening program. Parents of the probands were classified into the three known phenotypes by calculating the sum of cystine, ornithine, arginine, and lysine excretion. Although parents of type I/I homozygotes excreted amounts of cystine in the normal range, their offspring excreted significantly greater amounts of urinary cystine than did children who have type I/III genetic compounds. This observation suggests that types I and III cystinuria mutations might involve two distinct genetic loci. Children with type I/I homozygous cystinuria often excrete cystine at levels greater than the theoretic solubility limit and may be at greatest risk for nephrolithiasis. We outline an approach to monitoring children with cystinuria who come to medical attention before formation of cystine stones.

Arginine↗
PubMed2002

[Variants of surgical treatment of lateral postoperative abdominal hernia by a combined method].

616 patients with postoperative abdominal hernias (AH) were treated, 124 (20%) of them had lateral hernias. By M. Yatsentyuk classification, there were 41 (33.1%) patients with small hernias, 37 (29.8%)--with middle-size, 35 (28.2%)--with big, 6 (4.3%)--with very large, 5 (4%)--with giant hernias. Two operative techniques for lateral AH based on an original method of combined plastic surgery were applied in 37 patients. Good immediate and long-term results were achieved in all the patients. There were no recurrences.

Combined Modality Therapy↗
PubMed1991

[The classification of atypical forms of neurofibromatosis].

Neurofibromatosis (NF) represents not an entity but a group of several forms which differ as to symptoms, prognosis and inheritance. In 1982 Riccardi suggested a classification into eight categories. Two of these--Von Recklinghausen NF-1 and bilateral acoustic NF-2- were defined in 1987 by a National Institutes of Health Consensus Development Conference. We describe 13 patients whose symptoms do not fit the diagnostic criteria for NF-1 and NF-2. 6 subjects can be classified as segmental NF-V. One of these patients was remarkable in having iris hamartomata, while his daughter was affected with NF-1. Another (female) patient in this group had areolar freckling, a finding not yet reported in NF patients. 4 cases belong to the late-onset NF-VII category, 3 of whom developed a neurofibrosarcoma. Two subjects are fist-degree relatives (mother and son). We are not aware of familial occurrence of NF-VII. Two further subjects were assigned to the variant form of NF, NF-IV. One patient had symptoms similar to NF-2 but the minimal diagnostic criteria were not fulfilled. Nevertheless, we consider his classification as NF-2 in view of a pattern of intracranial calcification repeatedly and exclusively found in NF-2. In general, assignment to a category of NF is important for appropriate patient management and genetic counselling. Classification of individual patients may be arbitrary at the time.

Adolescent↗
PubMed1997

Immunohistochemical expression of Bcl-2 oncoprotein in EBV-associated nasopharyngeal carcinoma correlated to histological type and survival.

Expression of Bcl-2 is associated with inhibition of apoptosis and extension of cell survival. In vitro Bcl-2 protein expression is up-regulated by the EBV-latency associated antigen latent membrane protein (LMP-1). We have investigated the relationship between the presence of EBV-DNA screened by means of sensitive nested-PCR, nasopharyngeal carcinoma (NPC) histological types according to two different schemata (WHO and Micheau classifications) and Bcl-2-124 immunohistochemical expression in 55 biopsy samples of NPC. EBV genome was detected in 100% of samples with sufficient DNA quality to support the previous view that all types of NPC are variants of EBV-infected neoplasia. Bcl-2 was observed in the basal layer of normal nasopharyngeal mucosa and also at cytoplasmic level in 42 of 55 (76.4%) NPC cases. Mitotic neoplastic cells usually showed strong cytoplasmic and chromosomal staining, a finding not well referred to previously. Bcl-2 expression was significantly associated (p<0.05) to undifferentiated NPC (UNPC) when a histological classification with only two major microscopical types was applied. No close correlations were found between the presence of EBV-DNA, NPC location, clinical stage and age or sex of the patients in relation to Bcl-2 positive expression. However, when comparing Bcl-2 expression and known survival mean of the patients, significant differences were observed (p<0.001) so that mean survivals were 31.1, 24.4, 52.2 and 54.1 months respectively for NPC patients with -, +, ++ and Bcl-2 immunoreactivity. Nevertheless this better clinical outcome in Bcl-2 NPC positive cases may depend on the histological type due to close relationship with UNPC. Only studies of larger series with long-term follow-up and multivariate analyses may document whether Bcl-2 expression is an independent prognostic marker in the evolution of NPC patients.

Adolescent↗
PubMed1994

Identification of genotypes of hepatitis C virus by sequence comparisons in the core, E1 and NS-5 regions.

Isolates of hepatitis C virus (HCV) show considerable nucleotide sequence variability throughout the genome. Comparisons of complete genome sequences have been used as the basis of classification of HCV into a number of genotypes that show 67 to 77% sequence similarity. In order to investigate whether sequence relationships between genotypes are equivalent in different regions of the genome, we have carried out formal sequence analysis of variants in the 5' non-coding region (5'NCR) and in the genes encoding the core protein, an envelope protein (E1) and a non-structural protein (NS-5). In the E1 region, variants grouped into a series of six major genotypes and a series of subtypes that could be matched to the phylogenetic groupings previously observed for the NS-5 region. Furthermore, core and E1 sequences showed three non-overlapping ranges of sequence similarity corresponding to those between different genotypes, subtypes and isolates previously described in NS-5. Each major genotype could also be reliably identified by sequence comparisons in the well conserved 5'NCR, although many subtypes, such as 1a/1b, 2a/2c and some of those of type 4, could not be reliably distinguished from each other in this region. These data indicate that subgenomic regions such as E1 and NS-5 contain sufficient phylogenetic information for the identification of each of the 11 or 12 known types and subtypes of HCV. No evidence was found for variants of HCV that had sequences of one genotype in the 5'NCR but of a different one in the E1 or NS-5 region. This suggests that recombination between different HCV types is rare or non-existent and does not currently pose a problem in the use of subgenomic regions in classification.

Base Sequence↗