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At least 163 records · Page 9Linked to original sources
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↗
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↗
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↗
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↗
PubMed1991

Sinonasal papillomas and human papillomavirus: human papillomavirus 11 detected in fungiform Schneiderian papillomas by in situ hybridization and the polymerase chain reaction.

A series of 19 paraffin-embedded sinonasal papillomas (four squamous papillomas, three fungiform papillomas, nine inverted papillomas, and three cylindrical cell papillomas) were investigated for evidence of human papillomavirus (HPV) infection using immunohistochemistry (polyclonal antibody to HPV capsid antigen), in situ hybridization (DNA probes for HPV 6/11, 16/18, and 31/33/35), and the polymerase chain reaction (primers and probes for HPV 6, 11, 16, 18, and 33). All three fungiform papillomas were positive by all three techniques: immunohistochemistry, in situ hybridization for HPV 6/11, and the polymerase chain reaction for HPV 11. None of the other lesions contained detectable HPV using the specific probes included in this study. These results support the continued classification of fungiform papilloma as a distinctive variant of schneiderian papilloma characterized by a predominantly exophytic growth pattern and an association with HPV 11.

Adult↗
PubMed1985

Cytogenetic study in six Spanish patients with Burkitt's lymphoma.

A cytogenetic study carried out on affected tissues of six children with Burkitt's lymphoma revealed five cases with a typical translocation (8q-; 14q+) and one with a variant t(2p-; 8q+). Additional cytogenetic variations were present in three cases. One had two acrocentric marker chromosomes comprised of material from chromosome #1 (1q21----q44) translocated to the Y gonosome. The other two cases had a cytogenetic alteration of chromosome #12. Cytogenetic studies carried out systematically in Burkitt's lymphoma could be a great help in possibly establishing differences in the biologic and clinical aspects of cases presenting with the t(8;14) versus cases with variant translocations, as this would allow for classification of these patients into groups which, at present, cannot be differentiated using other diagnostic methods.

Adolescent↗
PubMed2025

Optical Genome Mapping Is a Powerful Diagnostic Tool in Non-Hodgkin Lymphoma.

Non-Hodgkin lymphoma (NHL) is a diverse and heterogeneous group of hematological malignancies. These lymphomas arise from the clonal proliferation of either B/T or natural killer lymphocytes, and their correct classification relies partly on identifying characteristic structural variants and copy number alterations. Current standard-of-care technologies for detecting these genomic features, chromosome banding analysis (CBA) and fluorescent in situ hybridization (FISH), are labor intensive and have specific limitations. CBA has low resolution and relies on viable cell culture, whereas the targeted approach of FISH does not provide the whole genome view required for comprehensive disease characterization. This highlights the need for higher-resolution nontargeted genomic methods. Previous studies have evaluated optical genome mapping (OGM) as a whole genome alternative for cytogenomic characterization in NHL diagnostics but were restricted in number and to cases with peripheral blood and/or bone marrow invasion. Here, we selected a comprehensive cohort of 110 NHL cases (79 B-NHL and 31 T-NHL/natural killer-NHL) derived from different types of tissue biopsies, all with established histopathological diagnoses. Seventy-eight samples were genomically well characterized at diagnosis by CBA and FISH. The remaining 32 cases were included because of previous CBA failure, although FISH data were available for 20 cases. OGM provided informative results in 94% of the cohort, with a high concordance rate of 97.6% compared with CBA/FISH in detecting clinically relevant aberrations. The 2 variants that were missed were both present at the detection threshold of OGM. In contrast, OGM successfully resolved 26 samples with previous CBA failure and detected 3 additional disease-defining events, resulting in diagnostic reclassification of 1 patient. Finally, OGM identified novel recurrent aberrations that warrant further investigation into their pathogenetic implications. To conclude, OGM robustly detects clinically relevant structural variants and copy number alterations and presents a promising alternative to CBA and FISH in routine diagnostic evaluation of NHL.

Humans↗
PubMed1990

Episodic paroxysmal hemicrania: a further case and review of the literature.

Episodic paroxysmal hemicrania was delineated as a clinical entity only two years ago, separating patients whose attacks remained grouped in bouts lasting weeks, from those who started irregularly and lapsed into chronicity or began and continued in the chronic state. A further case of the episodic variety and a review of the nine previously recorded cases is reported. The division into episodic and chronic variants of paroxysmal hemicrania conforms with the classification of cluster headache. The similarity of the two conditions is emphasised although the response to indomethacin in paroxysmal hemicrania is a special feature.

Adult↗
PubMed1991

Histopathologic features of high-grade non-Hodgkin's lymphomas in acquired immunodeficiency syndrome. The French Study Group of Pathology for Human Immunodeficiency Virus-Associated Tumors.

High-grade B-cell non-Hodgkin's lymphomas are observed in 5% to 10% of patients with acquired immunodeficiency syndrome. To describe their histologic subtypes, a group of pathologists was formed. One hundred thirteen cases were reviewed and classified according to the Working Formulation, the updated Kiel classification, and a recent description of morphologic variants of high-grade B-cell non-Hodgkin's lymphoma. Three major types of intermediate- or high-grade lymphomas were observed: (1) large-cell or centroblastic mainly polymorphic lymphomas with a component of immunoblasts (35 cases); (2) immunoblastic lymphomas with plasmablastic and plasmacytic features in most cases (33 cases); and (3) small non-cleaved cell Burkitt's or non-Burkitt's lymphoma (41 cases), with 15 cases fitting typical criteria of Burkitt's lymphoma and 26 heterogeneous cases in which the size and shape of the cells and the presence of plasmablastic features varied. The most frequent pathologic sites of involvement at presentation were the lymph nodes, gastrointestinal tract, bone marrow, brain, oral cavity, and muscles. A comparison between the histologic type and the site of involvement showed that most cases involving lymph nodes, bone marrow, or muscles were small noncleaved cell Burkitt's or non-Burkitt's lymphomas, while those that affected the gastrointestinal tract, brain, and oral cavity were centroblastic or immunoblastic lymphomas with consistent plasmacytic differentiation. In 10 cases, previous persistent generalized lymphadenopathy syndrome was present. In 13 cases, the lymphomatous proliferation was associated with follicular or diffuse hyperplasia seen on the same lymph node biopsy specimen or in another lymph node.

Acquired Immunodeficiency Syndrome↗
PubMed1985

[Teratoma].

The current concepts of the histogenesis of teratoma and criteria for the morphological diagnostics of its histological variants recommended by the WHO International Histological Classification of Tumours are presented.

Adolescent↗