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At least 919 records · Page 51Linked to original sources
PubMed1993

The Lennox-Gastaut syndrome.

One of the most challenging areas in nosology is in the field of severe generalized epilepsy of early childhood. This is certainly true in the case of Lennox-Gastaut syndrome (LGS), an age-related epileptogenic encephalopathy which comprises several types of generalized seizures including tonic seizures, atypical absence seizures and frequent status epilepticus. EEG shows generalized slow spike waves, and as the disease progresses, cognitive functions deteriorate. LGS is listed in the 1989 classification of the International League Against Epilepsy alongside epilepsy with myoclonic astatic seizures and West's syndrome. A number of variants or atypical forms have been proposed. As a result, differential diagnosis presents a major challenge and includes specific generalized epilepsies, i.e., metabolic or inflammatory; secondarily generalized epilepsies, i.e., those arising from the frontal lobe; and severe forms of idiopathic generalized epilepsy, i.e., Doose syndrome. Antiepileptic drug (AED) treatment of LGS has been disappointing. Results obtained from anterior callosotomy have been promising, but only a small number of patients have been evaluated. Although the syndrome is rare, the severe nature and intractability of LGS emphasizes the need for the development of specific AEDs which would completely modify the quality of life for these patients.

Anticonvulsants↗
PubMed2006

[Fibrohistiocytic skin tumors].

The fibrohistiocytic tumors of the skin are a heterogeneous group of dermal/subcutaneous mesenchymal neoplasms which show fibroblastic, myofibroblastic and histiocytic (macrophage-like) differentiation, often one beside the other in the same tumor. "Fibrohistiocytic" means in this context the morphologic similarity of the cells with fibroblasts and histiocytes. The WHO classification of 2005 includes the following entities as fibrohistiocytic tumors of the skin: BENIGN: 1. Fibrous histiocytoma (FH)/(synonymous: Dermatofibroma. Variants of FH: 1a. cellular fibrous histiocytoma, 1b. atypical (pseudosarcomatous) fibrous histiocytoma, 1c. aneurysmatic fibrous histiocytoma, 1d. epithelioid fibrous histiocytoma; 2. dermatomyofibroma; 3. (juvenile) xanthogranuloma. INTERMEDIATE: 4. plexiform fibrohistiocytic tumor; 5. dermatofibrosarcoma protuberans; 6. atypical Fibroxanthoma. MALIGNANT: 7. malignant fibrous histiocytoma. All these entities are reviewed in this paper with particular attention devoted to differential diagnostic considerations.

Diagnosis, Differential↗
PubMed2006

Anatomical and surgical considerations of the external branch of the superior laryngeal nerve: a systematic review.

The anatomical course of the external branch of the superior laryngeal nerve (EBSLN) is variable, and a consistent approach to its preservation during thyroid surgery is needed to reduce risk of post-operative voice impairment. Despite agreement that careful dissection in the region of the superior thyroid pole is required, there is no accepted 'best' approach, nor any universal acknowledgement that location of the EBSLN is actually necessary. The popular cernea classification of EBSLN has limitations, including its decreased reliability with increased thyroid size and its irrelevance in cases of 'buried' variants. * Recent work has identified factors such as ethnicity and stature in the prevalence of EBSLN variants. Consistent approaches to the post-operative detection of EBSLN injury are needed to build an accurate picture of the incidence of surgical nerve injury. Then a standardised approach to EBSLN preservation may emerge.

Clinical Trials as Topic↗
PubMed2000

[Specific aspects of thrombocyte system of serotonin in patients with different manifestations of schizoaffective psychosis].

45 women with different manifestations of schizoaffective psychosis (SAP) were examined. The diagnosis corresponded to ICD-10 (F25). According to the classification elaborated in Mental Health Research Centre of Russian Academy of Medical Sciences, groups of patients were identified with different variants of the psychoses course: a nuclear SAP type; a borderline SAP variation with phasic-recurrent course; SAP with progredient variation (schizoaffective variation of schizophrenia). The patients were examined both during the attack and remission. A rate of serotonine uptake (Vmax) in blood platelets, a specific imipramine binding (Bmax) and the level of serotonin in blood platelets were evaluated. It was found that dynamics of both Vmax and the level of serotonin in different SAP types were different, that was related to clinical and biological SAP heterogeneity. A tendency to decreasing of serotonin system functional activity was found in progredient SAP variations, especially during the remission, which was of low quality in these cases. On the contrary, in the borderline variations the indices of the decreased function of serotonin system corresponded well to those of acute psychosis. In nuclear type--a type with the most favourable course of psychosis--any significant changes weren't revealed as compared with the normal parameters.

Acute Disease↗
PubMed1998

The diagnosis of Sjögren's syndrome: definition and validation of classification criteria for this disorder.

Classification criteria currently exist for most of the rheumatic diseases. Different criteria sets have also been proposed in the past for Sjögren's syndrome (SS), but none of these has been validated and no single one is in general use by the entire scientific community. Between 1988 and 1996 the European Study Group for the Classification Criteria for SS performed a multicenter study in which a new classification criteria set for this disease was defined and then validated. This European set of classification criteria for SS is rapidly becoming the most widely accepted procedure to classify patients with the primary and secondary variants of the syndrome.

Diagnosis, Differential↗
PubMed2000

[The relationship between clinical types of postinfarction angina and stenosis of ischemia-related artery].

OBJECTIVE: To approach the pathogenesis of postinfarction angina and set up its treatment guidelines. METHODS: 67 patients with postinfarction angina undergoing coronary angiography during the hospitalization were studied. RESULTS: (1) According to the clinical classification of angina pectoris, spontaneous angina is the most common type (43.9%); mixed angina is second (25.7%), effort angina and variant angina are relatively low frequency (16.7% & 13.6%). (2) Stenosis >or= 90% in the ischemia-related artery accounted for the anginal symptoms constituted 100%, 82.8%, 72.7% and 44.4% of the cases with mixed angina, spontaneous angina, effort angina and variant angina respectively. (3) Postinfarction angina caused by non infarction-related artery was relatively less frequent (8.9%). CONCLUSIONS: Severe residual stenosis of infarction-related artery is the main pathologic factor on the pathogenesis of postinfarction angina, so early interventional therapy or bypass surgery should be taken.

Adult↗
PubMed1990

[Classification of circumscribed scleroderma. A multicenter study of 286 patients. The Scleroderma Study Group of the Society of Dermatologic Research].

In a multicentre study performed by the German Working Group for Dermatological Research a total of 286 female and male patients with circumscribed scleroderma (morphoea) were examined with reference to form and extent of their skin manifestations (e.g. progressive idiopathic atrophodermia, Pasini-Pierini Type) and systemic involvement. On the basis of the literature and our observation of circumscribed scleroderma classification into three types appears to be appropriate: a plaque-type (with generalized circumscribed scleroderma as the most severe variant), a linear type (with pansclerotic disabling morphoea as the most severe variant) and a profound type (with eosinophilic fasciitis as the most severe variant).

Adolescent↗
PubMed1988

Relationship between Mycobacterium avium, Mycobacterium paratuberculosis and "wood pigeon mycobacteria". Determinations by DNA-DNA hybridization.

The DNA-DNA homology percentages obtained in this study indicate that M. avium and M. paratuberculosis belong to one species. Consequently, M. paratuberculosis ought to be considered a variant of M. avium, and the following designations are proposed: Mycobacterium avium, subsp. avium. Mycobacterium avium, subsp. paratuberculosis. Identification and classification of "wood pigeon mycobacteria" occurring in wild animals have been problematic due to their dysgonic and mycobactin-dependent growth. DNA-DNA homology percentages indicate that these bacteria are closely related to reference strains both of M. avium and of M. paratuberculosis. "Wood pigeon mycobacteria" should therefore be classified as atypical strains of M. avium, and the following designation is proposed: Mycobacterium avium subsp. columbae.

Animals↗
PubMedDate not supplied

[Correlations between conventional allergometry and the Palmer types in interpretation of tuberculin skin tests].

In view of differentiating post-vaccinal allergy from that developing after tuberculosis infection, the authors have investigated comparatively intradermal-reactions to tuberculin according to classical allergometry, and to the 4 types described by Palmer-Edwards in a group of 1549 students and 211 patients. All the subjects were tested with 2 units of PPD IC 65. It was noted that the type I and II Palmer reactions corresponded, in the majority of the cases, to intense, or hyperergic ID reactions, while the types III and IV of Palmer corresponded to slightly positive, or to negative ID reactions. The presence of the post-vaccinal scar does not appear to influence significantly the type of the reaction, but the presence of active specific lesions is accompanied by reactions of type I and II of the Palmer classification. It is concluded that although the Palmer types do not allow to make a clear differentiation between the two variants of allergy they provide however useful indications for the interpretation of IDR in a more sophisticated manner, as compared with the conventional allergometry.

Adolescent↗
PubMedDate not supplied

[Characterization of neuronal ceroid lipofuscinosis in Venezuelan children].

INTRODUCTION: Neuronal ceroid lipofuscinosis (NCL), represents a group of inherited neurodegenerative disorders. Based on the age of the patient at onset, clinical course and ultrastructural morphology it has been identified three clinical types for the pediatric group: 1) Infantile NCL (INCL); 2) Late infantile NCL (LINCL); and 3) Juvenile NCL (JNCL). Other variants or atypical forms represent around 20% of the NCL in different populations. Genetic advances have made possible a better characterization, diagnostic and classification of these disorders. CASE REPORTS: We present the clinical, neurophysiological, neuroradiological, and morphological data from 6 patients with NCL, who were assessed at the pediatric neurology department of the Hospital Universitario de Maracaibo during a ten years period (1993 2003). All 6 cases corresponded with the late infantile form. Age of onset ranged form 2 to 5 years. For most of the patients initial symptoms included seizures, psychomotor delay, accompanied by macular degeneration and optic atrophy. The EEG was characterized by high voltage spikes elicited by low frequency photic stimulation, in 5 cases. Neuroimaging findings were characteristic of the late infantile form of the NCL. In three patients a decreased intensity of signal was seen in the thalami and putamen on T2-weighted images. The ultrastructural examination of the samples obtained through a biopsy showed curvilinear bodies in all patients. CONCLUSION: There is not epidemiological data of the NCL in Venezuela; it is presumed the presence of clinical forms and variants in the pediatric group. This first study could contribute to the knowledge and a better research of this group of disorders in our population.

Child, Preschool↗
PubMed1995

Histopathology, classification, and grading of gliomas.

Neoplastic transformation occurs in all glial cell types of the human nervous system, producing a wide variety of clinico-pathological entities and morphological variants. Astrocytomas are most common and span an unusually wide spectrum, ranging from the slowly growing juvenile pilocytic astrocytoma to the highly malignant glioblastoma multiforme. Diffusely infiltrating astrocytomas of the cerebral hemispheres show an inherent tendency for progression towards a more malignant phenotype. This change is morphologically categorized in histologic grading schemes (e.g., WHO Grade II to IV) and is associated with the sequential acquisition of genetic alterations, including mutations in the p53 and homozygous deletions of the p16 tumour suppressor genes. Loss of heterozygosity on chromosomes 10 and 19q as well as amplification of the EGF receptor are largely restricted to malignant gliomas and thus considered late events in astrocytoma progression. Gliomas often show phenotypic expression of different glial cell lineages (e.g., oligoastrocytoma). Recent studies suggest that the occurrence of mixed gliomas is not indicative of a polyclonal origin but rather reflects altered gene expression, leading to a change in the balance of growth factors influencing glioma differentiation.

Astrocytoma↗
PubMed1996

Comparative diagnoses of twin zygosity by SSLP variant analysis, questionnaire, and dermatoglyphic analysis.

Zygosity diagnosis has been performed in 79 pairs of twins using three methods. Simple sequence repeat length polymorphism (SSLP) analysis allows an efficient classification (MZ or DZ) with only a few markers following a simplified technique of extraction and amplification. A method based on a full questionnaire completed by parents about twin similarity correctly classifies 97.46% of the pairs; 92.41% are correctly classified using only four questions as suggested by logistic regression analysis. The third method, using dermatoglyphic analyses, correctly classifies 86.76% of pairs. To lower the cost of DNA diagnosis we stress the possibility of limiting its use to pairs with scores in the overlap area between MZ and DZ twins with a validated questionnaire.

Child↗
PubMed2026

Copy Number-low/TP53-mutated Endometrial Cancer With Wild-type p53 Immunoexpression: Implications for Risk Stratification and Management When Using Next-generation Sequencing for Molecular Classification.

Endometrial cancers with the Cancer Genome Atlas (TCGA) molecular profile of TP53-mutated, POLE-wild-type, and microsatellite-stable generally exhibit a high burden of copy number (CN) alterations and carry an increased risk for adverse outcomes, meriting maximal adjuvant therapy. In contrast, the prognosis associated with a TP53 mutation that coexists with a POLE mutation or microsatellite instability aligns with that of ultramutated or hypermutated cancers, respectively. In this study, we characterized a rare molecular subclass of endometrial cancers defined by TP53 mutation but low burden of CN alterations, wild-type p53 immunoexpression (immunohistochemistry [IHC]), and low TP53 variant allele frequency (median 13% and maximum 47%). Among 723 consecutive endometrial cancers prospectively classified using next-generation sequencing, 16 (2.2%) were CN-low/TP53-mutated/p53 wild-type IHC. Two additional cases were identified in a separate retrospective cohort of 32 recurrent low-grade early-stage endometrial cancers, bringing the total to 18 cases. They affected postmenopausal patients, exhibited low-grade endometrioid histotype, and were mostly confined to the uterus without lymphovascular space invasion. The recurrence rate was 6.25% (1/16) in the prospective cohort, and none died, placing their prognosis closer to that of CN-low than CN-high cancers. We conclude that next-generation sequencing-based TCGA classification of TP53-mutated, POLE-wild-type, microsatellite-stable endometrial cancers with TP53 variant allele frequency < 50% requires further evaluation using CN analysis and/or p53 IHC to detect this rare molecular category. IHC-based TCGA classification, such as the ProMisE protocol, will not be able to detect these cases because the p53 IHC pattern is wild-type and there are no distinguishing morphological features; this may be of relevance for analyzing ProMisE protocol-based clinical trials and outcomes studies. Long-term outcome studies are needed to refine risk stratification and treatment decisions for this unique molecular class of endometrial cancers that further contributes to the evolving understanding that the clinical significance of TP53 mutation in endometrial cancer is complex and depends on coexisting molecular alterations.

Humans↗
PubMed2002

Erythroleukemia: a need for a new definition.

The new WHO classification abolishes the frontier between RAEB-t with 20% of blasts and leukemia with 30% of blasts. We review the definitions of erythroleukemia and discuss the relationship between FAB AML6, RAEB-t and AML6 variant. We ask whether secondary erythroleukemias are the same entity as RAEB-t on survival, karyotype and cytologic characteristics. We suggest that 'AML6 variant' with pure erythroid lineage proliferation would be the real de novo erythroleukemia. Current FAB AML6 entity will probably be classified in either subgroup (1) multilineage dysplasia; (2) therapy-related leukemia; or (3) acute erythroid leukemia subdivided into erythroleukemia (erythroid/myeloid) and pure erythroid leukemia, in the WHO classification - a classification which highlights the importance of clinical and cytogenetic prognostic factors.

Adolescent↗
PubMed2004

The pathology of ductal-type pancreatic carcinomas and pancreatic intraepithelial neoplasia: insights for clinicians.

The phenotypic classification of pancreatic neoplasms is based on their cellular lineage. Thus, tumors with a ductal, acinar, and endocrine phenotype can be distinguished. Most pancreatic neoplasms show a ductal phenotype and can be classified as ductal adenocarcinomas. Less common tumors with a ductal phenotype are the variants of ductal adenocarcinoma, intraductal papillary mucinous neoplasm (including colloid carcinoma), mucinous cystic neoplasm, medullary carcinoma, and other rare tumors. Ductal adenocarcinomas most likely develop from ductal proliferative lesions arising in the pancreatic duct system. A recently adopted classification system for these lesions distinguishes between three grades of pancreatic intraepithelial neoplasia (PanIN). Molecular studies have revealed that PanIN-2 and PanIN-3 lesions represent a distinct step toward invasive carcinoma.

Adenocarcinoma↗
PubMed2002

Kidney pathology: current classification of renal cell carcinoma.

This report discusses the new cytogenetic classification of renal cell carcinoma (RCC) and its biological and clinical significance. It describes the four major types (clear cell, chromophil, chromophobe, and collecting duct) as well as rarer entities, such as small cell carcinoma, cystic RCC, rhabdoid variant of RCC, and unclassified RCC. Sarcomatoid carcinomas are a diverse group representing high-grade transformation of the other types. In addition to a description of the pathologic findings, there is a discussion of tumor markers and prognostic indicators. The clinical significance of the classification is discussed, with reference to recent reports.

Carcinoma, Renal Cell↗
PubMed1991

Protein pI alteration related to strain variation of infectious bronchitis virus, an avian Coronavirus.

Viral proteins of two strains of infectious bronchitis virus (IBV), which have different tissue trophism and serology, were separated on the basis of their isoelectric points (pI). The viruses have four structural proteins; the protein of greatest serological importance is found at the peplomer tip. The viral structural proteins separated by isoelectric focusing were identified by comparison to SDS-PAGE separations. Three protein bands were identical in pI and one protein band showed a difference in pI between strains. When the renatured viral proteins were Western blotted and reacted with strain-specific antiserum, antigen-antibody complexing was seen only at points corresponding to the strain-specific variant bands. For IBV strain Mass-41, antigen-antibody complexing occurred at a pI of 6.8, and, for IBV strain Ark-99, at 7.2. No cross reaction of antisera was observed for either strain. Since tissue affinities are a function of the viral peplomer-mediated attachment of virus to cells and are often directly related to pathogenicity, it appears that altered pathogenicity of strains of IBV may be detected by alteration of pI of the proteins. Classification by pI of proteins of at least the smaller viruses allows untypeable, highly pathogenic or persistent strains of these viruses to be characterized on the basis of variant proteins.

Antibodies, Viral↗