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At least 181 records · Page 10Linked to original sources
PubMed1984

Rare variant of complement C4 is seen in high frequency in patients with primary glomerulonephritis.

59 unselected patients with primary glomerulonephritis were phenotyped for alleles of the MHC-linked complement genes, C4A, C4B, and BF. A rare variant of the C4B locus, C4B*2.9, was found in 25% of these patients compared with only 2% of the normal population--a relative risk of 22.1 for glomerulonephritis in individuals with this variant. Subdivision of patients by histological classification of glomerulonephritis revealed a significant association of C4B*2.9 with the membranoproliferative form. There were no significant associations between primary glomerulonephritis or its subtypes and the other HLA markers tested.

Alleles↗
PubMed1986

Changes in the phenotype of human small cell lung cancer cell lines after transfection and expression of the c-myc proto-oncogene.

Small cell lung cancer growing in cell culture possesses biologic properties that allow classification into two categories: classic and variant. Compared with classic small cell lung cancer cell lines, variant lines have altered large cell morphology, shorter doubling times, higher cloning efficiencies in soft agarose, and very low levels of L dopa decarboxylase production and bombesin-like immunoreactivity. C-myc is amplified and expressed in some small cell lung cancer cell lines and all c-myc amplified lines studied to date display the variant phenotype. To investigate if c-myc amplification and expression is responsible for the variant phenotype, a normal human c-myc gene was transfected into a cloned classic small cell lung cancer cell line not amplified for or expressing detectable c-myc messenger RNA (mRNA). Clones were isolated with one to six copies of c-myc stably integrated into DNA that expressed c-myc mRNA. In addition, one clone with an integrated neo gene but a deleted c-myc gene was isolated and in this case c-myc was not expressed. C-myc expression in transfected clones was associated with altered large cell morphology, a shorter doubling time, and increased cloning efficiency, but no difference in L dopa decarboxylase levels and bombesin-like immunoreactivity. We conclude increased c-myc expression observed here in transfected clones correlates with some of the phenotypic properties distinguishing c-myc amplified variants from unamplified classic small cell lung cancer lines.

Animals↗
PubMed1992

[The classification of ileostomies].

From experience in the treatment of 527 patients the authors suggested an original classification of ileostomy. The systematization was based on the following criteria: the object of ileostomy, the shape and method for formation of the opening, the peculiarities of its construction, localization, functions, as well as the nature of complications linked with ileostomy. The suggested classification takes into account the modern concept on artificially formed intestinal fistulas, and gives a complete idea of patients with ileostomy. The use of the principles of the suggested classification in practice allows a rational variant of ileostomy to be chosen according to the existing conditions and effective measures for rehabilitation of patients with ileostomy to be marked out later.

Humans↗
PubMed1991

Ambiguous patterns in cellular differentiation in a case of "M3 variant" leukemia.

We report a case of acute non lymphoblastic leukemia in which clinical and cytological patterns corresponded closely to the M3 variant as defined in the FAB classification, although we did not find the characteristic t (15; 17) chromosomal translocation. However, cytochemistry, DNA content studies and immunophenotyping showed unusual patterns suggesting a monocytic differentiation of most of the blast cells, while a smaller population of blasts showed in contrast typical markers of granulocytic lineage.

Antigens, Neoplasm↗
PubMed1979

Goblet cell carcinoid tumor of the appendix. Report of five cases and review of the literature.

Five cases of goblet cell carcinoid tumor of the appendix showed characteristic histologic features that justified classification of these lesions as mucinous variants of carcinoid tumor. The tumor has low-grade malignancy, and metastases are uncommon. Resemblance to mucinous adenocarcinoma of the appendix is striking, and the features that help to differentiate the two lesions are delineated.

Adenocarcinoma, Mucinous↗
PubMed1986

Acute megakaryocytic myelosis preceded by myelodysplasia. Report of a case and review of the literature.

Acute megakaryocytic myelosis represents a distinct disease entity. As shown by a survey of the literature, it is a rapidly fatal disease, not preceded by a chronic myeloproliferative disorder, and mostly refractory to cytotoxic treatment. The first manifestation is pancytopenia with initial absence but quick development of hepatosplenomegaly. In contrast to "acute myelofibrosis", which is characterized by hyperplasia of all three haematopoietic lineages, a purely megakaryocytic proliferation develops together with a slight reticulinic fibrosis. Immature megakaryocytic cells may appear in the circulation, allowing classification of the disease as a variant of acute non-lymphatic leukaemia. This view is stressed by the observation of a preceding myelodysplastic phase in the case reported here.

Bone Marrow↗
PubMed1984

[Morpho-clinical variants of chronic glomerulonephritis and their significance for the evaluation of the severity of the disease].

The study of the morphological, clinical and functional manifestations of compensated chronic glomerulonephritis (CGN) in 317 patients revealed the advantage of the morphoclinical variants as compared to the morphological types for the evaluation of the gravity and prognosis of the disease. The morphoclinical variant means the combination of the morphological and clinical types. It was found that the morphoclinical variants of CGN determine the probability of the tubulointerstitial component, which deteriorates the prognosis of the disease more precisely than its morphological types. Renal dysfunction is more closely connected with the morphoclinal variant of CGN than with the morphological type. The data obtained are in favour of developing a morphoclinical classification of CGN on the basis of the morphoclinical variants of the disease.

Adolescent↗
PubMed1984

[Alloalbuminemia. Description of a case].

The authors describe an albumin variant of a very slow type, founded in a family in Arco (Trento, Italy) living, that about the characters correspond with variant VR/VR (type B) of the classification of CISMEL. It is denominated TN/TN in conformity with standards of classification of the same CISMEL, and it is the first case reported in literature in our Province.

Aged↗
PubMed1988

Growth hormones. 1. Polymorphism (minireview).

Pituitary growth hormone (GH) is not a single molecular species, but a whole set of similar molecules, the individual specific characteristics of which constitute the polymorphism of this hormone. The present paper deals mainly with various forms of human GH, called "variants", and touches on this polymorphism in other species as well. The 22 K variant (MW = 22,000 daltons) is the predominant form of GH to which all other variants are compared as to chemical structure and biological effect. These variants are classified into two large groups: 1) mass variants, the molecular weight of which is modified in comparison with that of 22 K; these can be subdivided into aggregated and non-aggregated forms, and 2) charge variants with modified electrophoretic mobility. Outside this classification are entities which are not yet well known; these include bioinactive GH, correctly detected by RIA but deprived of biological activity or, on the contrary, strongly bioactive GH lacking immunoreactivity and consequently difficult to study. Another outsider is the SV-hGH-2 variant encoded from a gene different from the hGH-N gene normally coding for the other variants. In this case, the product could be considered a true isohormone of 22 K and no longer a variant. The pituitary expression of this gene has never been evidenced to date, but according to recent data, it could be expressed at the placental level and be implicated in human placental growth hormone (hPGH) synthesis. hPGH is a newly-found GH in pregnant women which takes over pituitary GH from the 25th week onwards. After the GH molecules are released by the pituitary in the blood stream, they are partially taken up and carried by binding proteins. The physiological role of this phenomenon could be the setting up of a GH reservoir and a GH sparing process since the metabolic clearance rate of the complex GH-binding protein is slower than that of free GH, thus increasing the biological half-life of the hormone.

Animals↗
PubMed2019

Pediatric Cancer Variant Pathogenicity Information Exchange (PeCanPIE): a cloud-based platform for curating and classifying germline variants.

Variant interpretation in the era of massively parallel sequencing is challenging. Although many resources and guidelines are available to assist with this task, few integrated end-to-end tools exist. Here, we present the Pediatric Cancer Variant Pathogenicity Information Exchange (PeCanPIE), a web- and cloud-based platform for annotation, identification, and classification of variations in known or putative disease genes. Starting from a set of variants in variant call format (VCF), variants are annotated, ranked by putative pathogenicity, and presented for formal classification using a decision-support interface based on published guidelines from the American College of Medical Genetics and Genomics (ACMG). The system can accept files containing millions of variants and handle single-nucleotide variants (SNVs), simple insertions/deletions (indels), multiple-nucleotide variants (MNVs), and complex substitutions. PeCanPIE has been applied to classify variant pathogenicity in cancer predisposition genes in two large-scale investigations involving >4000 pediatric cancer patients and serves as a repository for the expert-reviewed results. PeCanPIE was originally developed for pediatric cancer but can be easily extended for use for nonpediatric cancers and noncancer genetic diseases. Although PeCanPIE's web-based interface was designed to be accessible to non-bioinformaticians, its back-end pipelines may also be run independently on the cloud, facilitating direct integration and broader adoption. PeCanPIE is publicly available and free for research use.

Child↗
PubMed2026

The importance of integrating genetic testing into reproductive medicine: a retrospective observational study investigating the monogenic causes of human infertility in couples considering ICSI.

The genetic landscape of human infertility is complex with diverse etiologies. Identifying the underlying etiology is crucial for guiding reproductive decisions and improving management for infertile couples. Here, we aim to report on the molecular spectrum of monogenic genetic causes of reproductive failure. Over a 3-year period, we recruited all infertile couples considering assisted reproductive technologies (ART) for whom the underlying genetic cause had been identified, in either partner, using exome sequencing (ES). Clinical data of all participants along with their hormonal profiles, sonographic findings and spermograms were recorded. The study included 50 couples with primary infertility. Clinically, male factor infertility was documented in 26 patients, female factor infertility in 10, while reproductive failure was unexplained in the remaining 14 couples. All participating couples had potentially disease-causing variants in infertility genes. ES identified variants related to male infertility in 26 men, while variants in female infertility-related genes were detected in the remaining couples (n = 24). According to ACMG classification criteria, 78% (39/50) of couples harbored pathogenic/likely pathogenic (P/LP) variants, whereas 22% (11/50) carried variants of uncertain significance (VUS). In view of the identified genetic etiologies, the cohort was stratified into two groups based on the predicted reproductive outcome: (1) couples with significantly impaired reproductive potential, and (2) couples who can have biological children using appropriate medical interventions. However, classifications involving VUS were interpreted cautiously and considered exploratory. This study provides further evidence for the molecular heterogeneity of human infertility and highlights the usefulness of genetic testing for infertile couples pursuing ARTs.

Humans↗
PubMed1984

Polymorphism of erythrocyte galactose-1-phosphate uridyl-transferase in Italy: segregation analysis in 693 families.

In the course of a population study in Italy, blood samples collected from 802 unrelated newborns and both their parents (when possible) have been examined for galactose-1-phosphate uridyltransferase (GALT) polymorphism. Electrophoresis and quantitative assay of GALT activity were not always sufficient for an accurate identification of the different GALT genotypes; segregation analysis provided better criteria for classification. A parent-child correlation coefficient for GALT activity equal to 0.107-0.155 was found when only the transmission of the normal allele was concerned, but the correlation rose to 0.618-0.682 when the Duarte and Los Angeles alleles were segregating. This confirmed the existence of a low (Duarte) and high (Los Angeles) activity variant. The overall validity of our genotype classification is supported by the good agreement between observed and expected mating types and segregations. The following gene frequencies were found for the different alleles: N = 0.9192, G = 0.0036, D = 0.0372 and LA = 0.0400.

Adult↗
PubMedDate not supplied

[Geometry and algebra of branches of the middle cerebral artery].

A classification of the cortical branches of the middle cerebral artery (MCA) is suggested by means of which each branch in any hemisphere can be qualified and identified in any variant of MCA branching. The principle of the classification consists in grouping the branches into arteries and trunks of the second, third, etc. order. Branches supplying blood to a certain sector of the lateral surface of the hemisphere are designated arteries. Their number and zone of branching are constant. Branches giving rise to 2 and more arteries are named trunks. Branching of the trunks, the number of trunks of the second, third, etc. order, and the site and type of origin of the arteries are extremely variable. Each trunk can be designated by a formula stating its order and the name of the artery supplied by this trunk. The arrangement of the MCA branches on the surface of the gyri and deep in the sulci, represented on the map of the lateral surface of the hemisphere, is designated conditionally as geometry of MCA branches. The order of branching of the trunks and the type of origin of the arteries, represented on abstract maps of the lateral surface of the hemisphere, are designated conditionally as algebra of the MCA branches. The variability of the geometry and algebra of the MCA branches must be taken into consideration in operations for extra-intracranial microanastomosis and in endovasal intervention on the MCA.

Cerebral Arteries↗
PubMed1983

Adult non-Hodgkin's lymphoma. Correlation of cell surface marker phenotype with prognosis, the new working formulation, and the Rappaport and Lukes-Collins histomorphologic schemes.

The interrelationships between histomorphologic classification, cell surface marker phenotype and prognosis were prospectively studied in 130 adults with non-Hodgkin's lymphomas. Within each of the classification schemes used there were certain histologic variants that exhibited heterogeneity of cell lineage as well as those that were extremely uniform. Diffuse lymphomas with cell populations consisting of large cells, or mixtures of large and small cells were the most heterogeneous phenotypically and were most resistant to precise definition of immunologic cell lineage. The new Working Formulation for Clinical Usage likewise exhibited considerable heterogeneity of phenotype even within well defined histomorphologic categories. Two immunologic phenotypic variables that conferred a significant favorable prognosis were the expression of surface membrane immunoglobulin (B derivation) and the simultaneous expression of a membrane mu and delta immunoglobulin heavy chain. The results of this study suggest that cell surface marker phenotypic determinations have well defined and potentially useful correlations with histomorphologic classification schemes, and are useful in predicting biologic behavior and prognosis. It is suggested that a knowledge of both immunologic phenotype and histomorphologic characteristics is necessary in formulating therapeutic decisions.

Humans↗
PubMedDate not supplied

[Angiographic study of the colonic vessels with a view to esophagoplasty].

Variants of the colic vessels were studied angiographically in 34 cadavers, drawing up an original classification of the colic arteries arising from the lower mesenteric artery. Sixteen variants of the left colic artery were found, which were grouped into five main types, the classical type being encountered in only 22.6% of the cases. In one case the lower mesenteric artery was absent. In coloesophagoplasty better results were obtained with the isoperistaltic transverse colon than with the upper ileocolon in 64% of the cases and similar results in 20%; in 16% of the cases the latter operation was preferable.

Angiography↗
PubMed2026

Tackling non-canonical splicing in arrhythmogenic cardiomyopathy to reduce the uncertain significance variants burden.

BACKGROUND: Splice-altering variants (SAVs), particularly those outside canonical splice sites, are an underappreciated contributor to inherited cardiovascular diseases. In arrhythmogenic cardiomyopathy (ACM), these variants frequently remain classified as of uncertain significance (VUS) due to limited predictive power and lack of transcript-level evidence, constraining genetic yield and clinical management. Our study aimed to determine the functional impact of SAVs in ACM genes and refine their classification using ACMG/AMP and ClinGen SVI criteria. METHODS: SAVs identified in 200 ACM probands underwent SpliceAI prediction, GTEx cardiac exon-usage annotation, and functional assessment using pSPL3-based minigene assays. Aberrant transcripts were quantified using Percent Splicing Alteration (PSA). Segregation data and ACMG/AMP criteria refined by ClinGen SVI were applied to integrate functional and clinical evidence for classification. RESULTS: Aberrant splicing was confirmed in 9/20 variants (45%), including synonymous, missense, and non-canonical intronic changes. SpliceAI scores correlated strongly with PSA values (R²=0.86). Case-control burden testing revealed significant enrichment of splice-altering variants in DSP, DSG2, DSC2 and FLNC. Integrating predictive algorithms with experimental validation and segregation analysis markedly enhances reclassification of 16/20 variants (80%). CONCLUSION: Splicing defects beyond canonical sites significantly shape ACM genetic landscape. Integrating predictive models with experimental validation clarifies uncertain variants bridging the gap between genomic uncertainty and clinical decision-making.

Humans↗
PubMed1990

Diffuse sclerosing variant of papillary thyroid carcinoma. S-100 protein immunocytochemistry and prognosis.

The recently published second edition of the WHO classification of thyroid tumours describes the diffuse sclerosing papillary carcinoma (DSPC) as a specific variant of papillary thyroid cancer (PC). Besides several histological hallmarks, this rare tumour is characterized by its occurrence in young individuals and is thought to have a less favourable prognosis than PC in general. The observations on two examples of this tumour presented herein, however, are at variance at this assumption. The neoplasms occurred in a 10 year old girl and a 34 year old woman. Each time, diffuse involvement of both thyroid lobes and bilateral cervical lymphadenopathy were seen. In one case, the carcinoma extended into the cervical soft tissue. Follow-up disclosed both patients to be without evidence of disease 2 and 13 years, respectively, after thyroid surgery. Immunocytochemically, both thyroid primaries as well as 7 other cases of DSPC reported in the literature showed dense accumulations of S-100 protein positive dendritic/Langerhans cells. Such infiltrations have been demonstrated to be correlated with a benign clinical course of PC. It is thus suggested that DSPC behaves similarly or even less aggressively than PC in general, at least if prominent Langerhans cell infiltration is present.

Adult↗
PubMed1987

Pathology of nasopharyngeal carcinoma. Proposal of a new histologic classification correlated with prognosis.

To establish a new histologic classification with better correlation with patient prognosis, the histologic features of nasopharyngeal carcinoma (NPC) were correlated with prognosis and clinical stage among 494 patients who had been followed a minimum of 5 years after initial radiotherapy. A slight modification of World Health Organization (WHO) classification by the separation of spindle cell variant from the nonkeratinizing (NK) and undifferentiated carcinomas (UD) provided a better prognostic correlation: keratinizing squamous cell carcinoma (KS), spindle cell carcinoma (SP), round cell carcinoma (RC), and mixed cell carcinoma (Mix, or NK); 5-year survival rates were 21%, 41%, 51.8%, and 54%, respectively. This prognostic distinction was further improved by dividing the three nonkeratinizing carcinomas (SP, RC, and Mix) into two subtypes each, according to the degree of cell anaplasia and pleomorphism: Type A (with marked anaplasia and/or pleomorphism), and Type B (with moderate or little anaplasia). The three Type A carcinomas had very similar 5-year survival rates (33.3 to 38.6%), as did the three Type B carcinomas (60% to 71.8%). Therefore, a working formulation for the malignancy of NPC emerged: high-grade malignancy (KS; 5-year survival, 21%), intermediate malignancy (Type A carcinomas, 5-year survival, 30%-40%), and low-grade malignancy (Type B carcinomas, 5-year survival rate, 60%-72%). The prognostic distinction remained true after stratification by clinical stage. Therefore, the histologic condition of the tumor of NPC correlated with patient's prognosis.

Adolescent↗