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At least 721 records · Page 40Linked to original sources
PubMed1993

Preliminary criteria for the classification of Sjögren's syndrome. Results of a prospective concerted action supported by the European Community.

OBJECTIVE: Different sets of diagnostic criteria have been proposed for Sjögren's syndrome (SS), but none have been validated with a large series of patients or in a multicenter study. We conducted the present study involving 26 centers from 12 countries (11 in Europe, plus Israel), with the goals of reaching a consensus on the diagnostic procedures for SS and defining classification criteria to be used in epidemiologic surveys and adopted by the scientific community. METHODS: The study protocol was subdivided into two parts. For part I, questionnaires regarding both ocular and oral involvement were developed; they included 13 questions and 7 questions, respectively. For part II a limited set of diagnostic tests was selected, and the exact procedure to be followed in performing these tests was defined. Part I of the study included 240 patients with primary SS and 240 age- and sex-matched controls. Two hundred forty-six patients with primary SS, 201 with secondary SS, 113 with connective tissue diseases but without associated SS, and 133 control patients were studied in part II. RESULTS: The study resulted in (a) the validation of a simple 6-item questionnaire for determination of dry eyes and dry mouth, which showed good discriminant power between patients and controls, to be used in the initial screening for sicca syndrome; and (b) the definition of a new set of criteria for the classification of SS. The sensitivity and specificity of the criteria in correctly identifying patients with either the primary or the secondary variant of SS were also determined. CONCLUSION: Using the findings of this prospective multicenter European study, general agreement can be reached on the diagnostic procedures to be used for patients with SS. Final validation of the preliminary classification criteria for SS is underway.

Connective Tissue Diseases↗
PubMed1993

Immunophenotyping of low-grade B-cell lymphoma in blood and bone marrow: poor correlation between immunophenotype and cytological/histological classification.

Results of immunophenotypic examinations of peripheral blood and/or bone marrow (BM), involved in low-grade B-cell non-Hodgkin's lymphomas, were compared with the results of cytomorphological and histopathological examinations in 133 adult patients. 69 cases of chronic B-lymphocytic leukaemia (B-CLL), 16 centrocytic (CC) lymphomas, 14 centroblastic-centrocytic (CB/CC) lymphomas, 15 immunocytomas (IC), 10 cases of hairy cell leukaemia (HCL), four prolymphocytic leukaemias (PLL), two B-CLL in transformation, one splenic lymphoma with villous lymphocytes (SLVL), one hairy cell leukaemia variant (HCL-V), and one lymphocytic lymphoma (LC) were classified according to the Kiel and/or FAB classification. Leukaemic disease was found in 105 cases. The following markers were used for immunocytology (APAAP technique) of blood and/or BM smears: CD19, CD5, CD10, CD11c, CD14, CD21, CD22, CD23, CD25, CD38 and TdT. All cases tested showed CD19, but no TdT expression. Every case of HCL had a distinct phenotype with expression of CD11c, CD22 and CD25 and the lack of CD5 and CD23 antigens. In all other NHL cases a very heterogenous expression of CD-antigens with no significant correlations to the cytomorphological subtypes was found. The expression of CD5 is a frequent but inconstant finding in lymphoproliferative diseases other than B-CLL, so 50% of CB/CC, 75% of CC and 80% of IC were CD5 positive. Our results indicate that, with the exception of HCL, the diagnostic relevance of immunophenotyping for the classification of cytomorphologically and histopathologically defined subtypes in blood and/or BM is of very limited value.

Aged↗
PubMed2002

[WHO classification of testicular tumors].

Twenty years after the first edition (1977), the WHO has presented the updated version of the "Histological typing of testis tumours". The revised classification was necessary because some clinically important new entities have been described in recent years. The most important is obviously the precursor lesion of germ cell tumors, which has been called "intratubular malignant germ cells". Such atypical cells appear in the tubules adjacent to the germ cell tumors, in some few cases (6%) also in the contra lateral healthy gonad and rarely in infertile men (1%). The precursor lesion can progress to franc germ cell tumor starting probably with seminoma, which still maintain the capability of differentiation (pluripotente cells) in all other types of non-seminomatous germ cell tumors. This lesion is missed in germ cell tumors of childhood and in spermatocytic seminomas, both seem to have a histogenetic history rather different from the other germ cell in adults. The categories used in the first classification have been preserved and some new diagnoses added. Most of the new diagnoses are subtypes--called "variants"--of well known tumors. Seminoma with syncytiotrophoblastic cells is a variant which should not be confused with choriocarcinoma. Spermatocytic seminomas are perfectly benign tumors but they become a life threatening disease when combined with sarcomas (new entity). In the group of mature teratomas the "dermoid cyst" appears as a benign subtype mostly observed in children. Unfortunately, however, the old term "teratoma with malignant transformation" was changed to "teratoma with malignant areas" in the 1998 classification. This is a harmless name for an extremely dangerous tumor in which one tissue overgrows the other and gives rise to somatic type sarcomas or carcinomas. Such tumors do not respond like germ cell tumors to the usual chemotherapy. Treatment should be tailored according to that used in standard management of the respective sarcoma or carcinoma. In the comments it is mentioned that the testis carcinoid could be a part of teratoma, but the diagnosis is listed in the group of "miscellaneous" tumors together with tumors of ovarian epithelial type. This is a very questionable decision because the normal testis does not contain neuroendocrine cells from which carcinoids would have to be able to develop. Teratomas, however, show plenty of them producing all kinds of typical hormones. "Large cell calcifying Sertoli cell tumour" has been recently described and can be sporadic or inherited. This morphologically peculiar tumor can be part of the Swiss syndrome also called Carney's complex. The patients have cardiac myxomas, spotty skin pigmentation, hormone active nodular hyperplasia of the adrenals and soft tissue myxomas. The newly appearing "mixed germ cell--sex cord/gonadal stromal tumours, unclassified" has a histology similar to the well known gonadoblastomas. In contrast to gonadoblastoma, however, these tumors occur in testes of genotypic and phenotypic normal males. From the practical, diagnostic point of view the new classification does not contain dramatic changes. For the therapy of germ cell tumor an assessment of risk factors found by the pathologists is extremely important. The most important independent predictors of relapse are tumor invasion of blood or lymph-vessels, absence of yolk sac elements and the presence of an embryonal carcinoma component. In the absence of such predictors a surveillance policy allows some patients to forgo chemotherapy.

Humans↗
PubMed1980

[Classification of epitheliomesenchymal odontogenic tumors].

In a group of 34 epitheliomesenchymal odontogenic tumours no difficulties were encountered in recognizing the seven-member group of ameloblastic fibroma (with ameloblastic odontoma and dentinoma included as variants) as distinct from group of odontomas (ameloblastic o. - 2x, complex o. - 20x, combined o. - 5x) The definition is rather a general one with the distinction of variants only sometimes possible. No ameloblastic fibrosarcoma or ameloblastic odontosarcoma were seen in the group; therefore, the question should be asked whether it is really expedient to keep independent places in the classification for so rare tumours.

Humans↗
PubMedDate not supplied

[Genetic errors of glycoprotein metabolism].

This is a review article on glycoprotein storage diseases. In each of the separate diseases there is a relatively characteristic combination of clinical lesions, enzyme deficiency and storage of glycoconjugates which form the basis of classification. For most of these disorders, demonstration of the enzymatic deficiency has led to accurate diagnosis of affected individuals recognition of variant and atypical forms, detection of carriers and prenatal diagnosis of affected fetuses. The studies have proved to be informative as to: 1) Identification of previously unrecognized diseases. 2) Identification of the metabolic products of the mutant genes. 3) Classification within a group. 4) Demonstration of genetic principles.

Congenital Abnormalities↗
PubMed2005

Postinfectious inflammatory disorders: subgroups based on prospective follow-up.

BACKGROUND: Acute disseminated encephalomyelitis (ADEM) refers to a monophasic acute multifocal inflammatory CNS disease. However, both relapsing and site-restricted variants, possibly associated with peripheral nervous system (PNS) involvement, are also observed, and a systematic classification is lacking. OBJECTIVE: To describe a cohort of postinfectious ADEM patients, to propose a classification based on clinical and instrumental features, and to identify subgroups of patients with different prognostic factors. METHODS: Inpatients of a Neurologic and Infectious Disease Clinic affected by postinfectious CNS syndrome consecutively admitted over 5 years were studied. RESULTS: Of 75 patients enrolled, 60 fulfilled criteria for ADEM after follow-up lasting from 24 months to 7 years. Based on lesion distribution, patients were classified as encephalitis (20%), myelitis (23.3%), encephalomyelitis (13.3%), encephalomyeloradiculoneuritis (26.7%), and myeloradiculoneuritis (16.7%). Thirty patients (50%) had a favorable outcome. Fifteen patients (25%) showed a relapsing course. Poor outcome was related with older age at onset, female gender, elevated CSF proteins, and spinal cord and PNS involvement. All but two patients received high-dose steroids as first-line treatment, with a positive response in 39 (67%). Ten of 19 nonresponders (53%) benefited from high-dose IV immunoglobulin; 9 of 10 had PNS involvement. The data were not controlled. CONCLUSIONS: A high prevalence of "atypical variants" was found in this series, with site-restricted damage or additional peripheral nervous system (PNS) involvement. Prognosis and response to steroids were generally good, except for some patient subgroups. In patients with PNS involvement and steroid failure, a favorable effect of IV immunoglobulin was observed.

Adult↗
PubMed2005

Efficient training algorithms for a class of shunting inhibitory convolutional neural networks.

This article presents some efficient training algorithms, based on first-order, second-order, and conjugate gradient optimization methods, for a class of convolutional neural networks (CoNNs), known as shunting inhibitory convolution neural networks. Furthermore, a new hybrid method is proposed, which is derived from the principles of Quickprop, Rprop, SuperSAB, and least squares (LS). Experimental results show that the new hybrid method can perform as well as the Levenberg-Marquardt (LM) algorithm, but at a much lower computational cost and less memory storage. For comparison sake, the visual pattern recognition task of face/nonface discrimination is chosen as a classification problem to evaluate the performance of the training algorithms. Sixteen training algorithms are implemented for the three different variants of the proposed CoNN architecture: binary-, Toeplitz- and fully connected architectures. All implemented algorithms can train the three network architectures successfully, but their convergence speed vary markedly. In particular, the combination of LS with the new hybrid method and LS with the LM method achieve the best convergence rates in terms of number of training epochs. In addition, the classification accuracies of all three architectures are assessed using ten-fold cross validation. The results show that the binary- and Toeplitz-connected architectures outperform slightly the fully connected architecture: the lowest error rates across all training algorithms are 1.95% for Toeplitz-connected, 2.10% for the binary-connected, and 2.20% for the fully connected network. In general, the modified Broyden-Fletcher-Goldfarb-Shanno (BFGS) methods, the three variants of LM algorithm, and the new hybrid/LS method perform consistently well, achieving error rates of less than 3% averaged across all three architectures.

Algorithms↗
PubMedDate not supplied

Tibial hemimelia of a different class.

A variant of tibial hemimelia, previously undescribed in the literature and not classifiable by either of the established classification systems, is described. The features of this condition include a short, deformed tibia; proximal subluxation of the fibula at the knee; a normal knee joint and an ankle joint that may look abnormal but falls short of true diastasis of the joint. Treatment of two cases by differential lengthening of the tibia and fibula using the Ilizarov device is described. This form of tibial hemimelia should be recognised as a separate variant as preservation of the foot and ankle with expected excellent function should be possible, unlike the more severe forms of this condition.

Age Factors↗
PubMed2026

Pangenomic analyses in the cultivated grapevine confirm high genomic collinearity and extensive dispensable gene content likely involved in adaptation.

Pangenomes have now been developed for several horticultural crops, yet the extent to which genome diversity in sequence and organization contribute to plant adaptation and major agronomic traits remains poorly understood. Here, we assembled the genomes of 9 cultivated grapevine varieties and compared the genomes of 15 cultivated grapevine varieties for variation in gene and TE content. We found that genomic collinearity is highly conserved among varieties. We still observed substantial variation across genomes. Notably, we identified across varieties 55,662 orthologous genes, of which 55.3% appears to be dispensable. Dispensable genes are enriched for functions related to adaptation to biotic and abiotic constraints, suggesting that they may play a role in adaptation. Comparing our results with a recently published study, we found substantial differences with ∼12.6% of the genes we classified as core genes being classified as dispensable genes in this other study. We then constructed a pangenome graph and used it to performed genome-wide association studies for 3 important traits in grapevine production, which allowed us to include large structural variants as markers in the analyses. We identified 32 loci that we did not detect when we used the PN40024 genome as a reference, 20 of which are newly reported associations. Overall, our results indicates that despite recent advances in characterizing plant pangenomes, current gene classification into core and dispensable gene categories should be taken with caution. They also highlight the value of incorporating structural variants into GWAS, to better characterize the genetic architecture of agronomic traits.

Vitis↗
PubMed1985

Cytometrically monitored neoplastic progression in the Nb bladder cancer model: selective proliferation of variant subpopulations.

The identification and understanding of neoplasm heterogeneity is essential to allow for more individually oriented treatment modalities. There is a tendency to limit the analysis of neoplasm heterogeneity to diagnostic classification only; however, recently refined methods of rapid subpopulation analysis should expand this restricted usage to monitoring of chemotherapeutic treatment. The documentation of the neoplastic progression of the Nb rat bladder cancer model as a function of variant subpopulation proliferation and selection is reported herein. This documentation represents the efforts of this laboratory to develop a flow cytometrically monitored animal bladder tumor model to evaluate the in vivo effects of chemotherapies on neoplastic subpopulations; particularly those subpopulations potentially metastatic or resistant to therapy. It is anticipated that this will increase our understanding of this model, and more specifically, tumor biology. This particular tumor initially occurred in an aged Noble male breeder rat.

Animals↗
PubMed2006

Disordered beta-catenin expression and E-cadherin/CDH1 promoter methylation in gastric carcinoma.

AIM: To investigate the distribution of beta-catenin in nuclei or membrane/cytoplasm of gastric carcinoma cells, the relationship between E-cadherin gene methylation and its expression, and the role of beta-catenin and E-cadherin as potential molecular markers in predicting tumor infiltration. METHODS: Twenty-nine cases of gastric carcinoma, classified as diffuse and intestinal variants, were selected for study. Nuclear and cytoplasmic proteins were purified and beta-catenin content was detected by ELISA. DNA methylation of E-cadherin/CDH1 gene promoter was studied by methylation-specific PCR and compaired with E-cadherin expression detected by immunohistochemistry. RESULTS: In 27 cases of gastric carcinoma, the ratio of beta-catenin content between nuclei and membrane/cytoplasm was correlated with the T-classification (r = 0.392, P = 0.043). The significance was present between T2 and T3 groups. No correlation was detected between diffuse and intestinal variants in terms of their beta-catenin distribution. In 21 cases of diffuse variants of gastric carcinoma, there was a difference in E-cadherin expression between CDH1 gene-methylated group and non-methylated group (29 % vs 71 %, P = 0.027). No correlation between CDH1 gene methylation and T-classification was found, neither was the significance between E-cadherin expression and tumor infiltration grade. CONCLUSION: Comparative analysis of nuclear and membrane/cytoplasmic beta-catenin can predict local tumor infiltration. E-cadherin/CDH1 gene methylation is an important cause for its gene silence in diffuse variant gastric carcinoma. Methylation of CDH1 gene in the absence of E-cadherin is an early event in gastric carcinogenesis.

Antigens, CD↗
PubMed1985

Chemical and histochemical studies of normal and diseased human gastrointestinal tract. V. A differential diagnostic method for the histochemical classification of glycoproteins.

A differential diagnostic scheme is described for the division of colonic epithelial glycoproteins into eleven histochemically distinct classes. The scheme depends upon the use of seven histochemical techniques which, collectively, permit the differential staining of O-sulphate ester, sialic acid and its side chain O-acyl variants and vicinal diols located on carbohydrate residues other than sialic acids. Elements of the scheme also provide a general approach to the classification of epithelial glycoproteins in anatomic sites other than the colon. Application of the scheme permitted the classification of the epithelial glycoproteins in the mucosa 0.5-5.0 cm from human colonic tumours and provided direct confirmation of previous observations that changes from normal in the relative proportions of either side chain O-acylated sialic acids or sialic acids and O-sulphate esters can occur independently of one another.

Colonic Neoplasms↗
PubMed2006

Complications of pulmonary resection: postpneumonectomy pulmonary edema and postpneumonectomy syndrome.

Bassed on the authors' review of the unusual variants of PPS and the body of published experience, a revision of the current classification scheme for PPS into a more comprehensive form is justified as follows: (1) by the nature of obstruction; and (2) by the time of onset. This classification encompasses early and late symptom onset, as well as considering both airway and vascular compression. This scheme argues in favor of an expanded cardiac work-up in addition to the measures outlined previously for airway assessment. Althought PPS remains a rare clinical entity, the refinement in the understanding of this condition and the evolution of treatment options have vastly improved patient outcomes. A careful evaluation of the patient must be done before embarking on treatment owing to the numerous etiologies for progressive dyspnea in the pneumonectomy patient.

Bronchial Diseases↗
PubMed1997

Conceptualization and treatment of bowel obsessions: two case reports.

Bowel obsessions have long been recognized in clinical settings, usually presenting as an overwhelming fear of losing bowel control in public. Conceptual issues with regard to this disorder have hampered treatment efforts. For example, disagreement exists as to its proper classification within the spectrum of anxiety disorders: it has been conceptualized both as a variant of obsessive-compulsive disorder and as a symptom of social phobia, panic disorder, and agoraphobia. In addition, the comorbidity of bowel obsessions and functional bowel disorders such as irritable bowel syndrome is not understood. While reports of pharmacological intervention exist, little has been written about psychological treatment techniques. This paper uses two cases studies of successful behavioral treatment of bowel obsessions as illustrations to address the above issues.

Adult↗
PubMed2001

Using Australian DRGs in Germany: a commentary.

Germany will begin a change to per case payment by DRG from January 2003. It has selected the Australian DRG classification as the basis for patient categorisation, in preference to the many other DRG variants around the world. The main aim is increase control over expenditure. We describe some of the reasons for high levels of spending on hospital inpatient care, including the fragmented insurance system and supplier-induced demand. We summarise the reasons why Australian DRGs were selected, and note some of the benefits that will accrue for Australia.

Australia↗
PubMed2002

Chronic lymphocytic leukaemia--the haematologic basis for diagnosis and treatment.

Clinically diagnosis may be incidental when absolute lymphocytosis is uncovered at routine medical examination. More usually there is a recurrent sinopulmonary infection reflecting a varying degree of humoral and cellular immune deficiency. Autoimmune phenomena may result in haemolytic anaemia or thrombocytopenia. Expanding tumour bulk underlies the lymphadenopathy which may be prominent. Diagnosis is confirmed on morphology of the smear where atypical variants need to be distinguished from other indolent lymphoproliferative disorders. Immunophenotyping is indispensable in classification. Prognosis is predicated by cytogenetics and markers of tumour biology that include beta-2 microglobulin and peripheral blood lymphocyte doubling time. Management is dictated by symptoms and signs of progression superimposed upon performance status that includes age. Disease that is asymptomatic and truly indolent, particularly in the elderly, qualifies for a careful watch-and-wait policy. In other circumstances stratification to therapy requires entry into peer-reviewed protocols if optimal outcome is to be achieved. Established regimens, of demonstrably equal efficacy, are pulsed single-agents exemplified by chlorambucil or combinations of cyclophosphamide with vincristine and prednisone. The purine analogues, particularly when administered with an alkylating agent and mitoxantrone, are emerging as superior options. In selected patients any properly accredited program will make provision for escalation in chemotherapy requiring haematopoietic stem cell transplantation on the one hand or use of serotherapy with CD52 antibodies on the other. Less commonly, but in a defined subgroup, immunoglobulins directed against membrane CD20 may be effective. Perspective for the generalist is anchored in recognising that the previous cavalier approach to drug medication, with or without radiotherapy, is unwise whereas integrated management is now the international standard of practice. The previous anachronism of dabbling by occasional therapists is to be deprecated since this will generally deny patients access to proper diagnosis and risk-adjusted multi-disciplinary treatment.

Antineoplastic Agents↗
PubMedDate not supplied

Carving chaos: genetics and the classification of mood and psychotic syndromes.

Though Kraepelin's century-old division of major mental illness into mood disorder and schizophrenia remains in place, debate abounds over the most appropriate classification. Although these arguments previously rested solely on clinical grounds, they now are rooted in genetics and neurobiology. This article reviews evidence from the fields of genetic epidemiology, linkage, association, cytogenetics, and gene expression. Taken together, these data suggest some overlap in the genes that predispose to bipolar disorder and schizophrenia. One gene, DAOA (D-amino acid oxidase activator, also known as G72), has been repeatedly implicated as an overlap gene, while DISC1 and others may constitute additional shared susceptibility genes. Further, some evidence implicates syndromes of co-occurring mood and psychotic symptoms in association with the putative risk alleles in overlap genes. From a nosologic perspective, the existence of overlap genes, coupled with the genotype-phenotype correlations discovered to date, supports the reality of the much debated schizoaffective disorder. Potential non-overlap syndromes--such as nonpsychotic bipolar disorder or cyclothymic temperament, on the one hand, and negative symptoms or the deficit syndrome, on the other--could turn out to have their own unique genetic determinants. If genotypes are to be the anchor points of a clinically useful system of classification, they must ultimately be shown to inform prognosis, treatment, and prevention. No gene variants have yet met these tests in bipolar disorder or schizophrenia.

Bipolar Disorder↗
PubMed2007

Single nucleotide polymorphism array analysis of cancer.

PURPOSE OF REVIEW: Classifying tumors and identifying therapeutic targets requires a description of the genetic changes underlying cancer. Single nucleotide polymorphism (SNP) arrays provide a high-resolution platform for describing several types of genetic changes simultaneously. With the resolution of these arrays increasing exponentially, they are becoming increasingly powerful tools for describing the genetic events underlying cancer. RECENT FINDINGS: The ability to map loss of heterozygosity (LOH) and overall copy number variations using SNP arrays is known. Techniques have recently been developed to map LOH at high resolution in the absence of paired normal data. Copy number variations described by SNP array studies are now reaching resolutions enabling the identification of novel oncogenes and tumor suppressor genes. The ability to determine allele-specific copy number changes has only recently been described. Moreover, SNP arrays offer a high-throughput platform for large-scale association studies that are likely to lead to the identification of multiple germline variants that predispose to cancer. SUMMARY: SNP arrays are an ideal platform for identifying both somatic and germline genetic variants that lead to cancer. They provide a basis for DNA-based cancer classification and help to define the genes being modulated, improving understanding of cancer genesis and potential therapeutic targets.

Chromosome Aberrations↗