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PubMed2025

Contributions of Common, Rare, and Somatic Genetic Variants to Incidence of Atrial Fibrillation.

IMPORTANCE: Atrial fibrillation (AF) has a complex genetic architecture involving common, rare, and somatic variants. The association between these components requires further investigation. OBJECTIVE: To examine the individual and combined contributions of polygenic, monogenic, and somatic genetic variants to AF incidence, and develop an integrated genomic model (IGM-AF) for improved risk prediction. DESIGN, SETTING, AND PARTICIPANTS: This cohort study used whole-genome sequence data from participants of the UK Biobank, with follow-up for AF events through hospital records, death registries, and self-report. The UK Biobank recruited participants aged 40 to 69 years in the UK between 2006 and 2010. Study data were analyzed from August 2022 to November 2024. EXPOSURES: IGM-AF comprising an AF polygenic risk score (PRS), a composite rare variant gene set (AFgeneset), and somatic variants associated with clonal hematopoiesis of indeterminate potential (CHIP). Clinical AF risk was estimated using the Cohorts for Heart and Aging Research in Genomic Epidemiology AF (CHARGE-AF) score. MAIN OUTCOMES AND MEASURES: The primary outcome was hazard ratios (HRs) for 5-year incident AF attributable to PRS, AFgeneset, CHIP, and their interactions. The predictive performance of IGM-AF and its components was quantified using HRs, C statistics, and reclassification indices. RESULTS: A total of 416 085 individuals (mean [SD] age, 56.6 [8.0] years; 224 642 female [54.0%]) with 30 797 AF cases were included. The PRS (HR per 1 SD, 1.65; 95% CI, 1.63-1.67; P < 1 × 10-8), AFgeneset (HR, 1.63; 95% CI, 1.52-1.75; P = 1.46 × 10-42), and CHIP (HR, 1.26; 95% CI, 1.15-1.38; P = 1.41 × 10-6) were associated with incident AF. The 5-year cumulative incidence of AF was at least 2-fold among individuals having all 3 genetic drivers (common, rare, and somatic drivers) compared with those with only 1 driver. Integration of IGM-AF with a clinical risk model (CHARGE-AF) showed higher predictive performance (C statistic, 0.80; 95% CI, 0.80-0.80) compared with IGM-AF and CHARGE-AF alone. The classification of the at-risk population for AF was improved when IGM-AF was added to CHARGE-AF (net reclassification index, 0.08; 95% CI, 0.07-0.09). CONCLUSIONS AND RELEVANCE: Results of this cohort study demonstrated the complementary value of common, rare, and somatic variants in shaping genomic AF risk. Leveraging comprehensive genetic information may enhance screening and preventive interventions for AF.

Humans↗

PubMed1984

[The Chance fracture and its variants].

Five cases of Chance fracture are reported, representing 0.6% of the spinal fractures treated at the Orthopedic Clinic of the University of Athens during the last 10 years. This fracture is frequently not recognized and diagnosis is delayed because of this fact. The mechanism and the clinical and radiological signs are discussed. A classification is proposed that contains four varieties of this lesion. The Chance fracture is discussed with regard to stability, as surgical stabilization is reserved for unstable fractures (types B, C, D).

Adult↗

PubMed2005

Molecular classification and biomarker discovery in papillary thyroid carcinoma.

Papillary thyroid carcinoma (PTC) is the most common thyroid malignancy, with an incidence of approximately 22,000 cases in 2004 in the USA. Incidence is increasing, with a global estimate of half a million new cases this year. PTC is found in a variety of morphologic variants, usually grows slowly and is clinically indolent, although rare, aggressive forms with local invasion or distant metastases can occur. In recent years, thyroid cancer has been at the forefront of molecular pathology as a result of the consequences of the Chernobyl disaster and the recognition of the role of Ret/PTC rearrangements in PTC. Nonetheless, the molecular pathogenesis of this disease remains poorly characterized. In the clinical setting, benign thyroid nodules are far more frequent, and distinguishing between them and malignant nodules is a common diagnostic problem. It is estimated that 5-10% of people will develop a clinically significant thyroid nodule during their lifetime. Although the introduction of fine-needle aspiration has made PTC identification more reliable, clinicians often have to make decisions regarding patient care on the basis of equivocal information. Thus, the existing diagnostic tools available to distinguish benign from malignant neoplasms are not always reliable. This article will critically evaluate recently described putative biomarkers and their potential future role for diagnostic purposes in fine-needle aspiration cytology samples. It will highlight the evolution of our understanding of the molecular biology of PTC, from a narrow focus on specific molecular lesions such as Ret/PTC rearrangements to a pan-genomic approach.

Adenocarcinoma, Papillary↗

PubMed1975

[Histological classification of malignant breast neoplasms. Recent concepts].

The recent histological classifications of breast malignant epithelial tumours place increased emphasis on several concepts: in situ carcinoma, difference of lobular carcinoma from other forms of breast cancer and histological factors of prognosis. The authors propose to discriminate: non infiltrating duct carcinoma (intraductal carcinoma); lobular carcinoma (in situ and infiltrating); infiltrating duct carcinoma in their usual form (80 p. 100 about of all breast carcinoma); among them, histological types with a less ominous prognosis, although relatively rare, are stressed (infiltrating papillary and comedo-carcinomas, tubular carcinoma, medullary carcinoma, colloid carcinoma, cylindroma, certain metaplastic variants, Paget's disease of the nipple); some features in unusual hosts are related. They mention the criteria of the Scarff and Bloom's "grading" and its importance from the point of view of prognosis, mainly for the usual infiltrating forms. Other malignant tumours of the breast (malignant cystosarcoma phyllodes, sarcomas, mammary metastases) are more scarcely seen (I p. 100 of the mammary neoplasms): their classification is succinctly recalled.

Breast↗

PubMed1987

Mucoepidermoid tumors of the lung.

Mucoepidermoid tumors of lung (MET) are rare tumors derived from the minor salivary gland tissue of the proximal tracheobronchial tree. The authors studied 58 cases of MET confined to the lung and used criteria derived from similar tumors of the salivary glands to separate them into low-grade and high-grade variants. The overwhelming majority of low-grade tumors behaved in a benign fashion, whereas 23% of high-grade tumors resulted in patient death. Prognostic factors which appeared to predict future aggressive behavior included high-grade classification, advanced stage at presentation, and perhaps lymph node metastases.

Adenoma, Pleomorphic↗

PubMed2006

Sonography of the first dorsal metatarsal artery of the foot.

PURPOSE: To describe the gray-scale and Doppler sonographic examination technique and appearances of the first dorsal metatarsal artery (FDMA) of the foot and discuss its clinical significance. METHODS: The dorsal arteries of foot-including the FDMA and the first plantar metatarsal artery-of 374 feet were studied using gray-scale and color Doppler sonography. Due to the difficulty of detecting the FDMA, a majority of them were identified by studying the web area just distal to the intermetatarsal space. The interosseous muscle was identified to determine the classification of the anatomic type of the FDMA. The sonographic results of 152 feet were compared with surgical findings. RESULTS: The average caliber of the FDMA was 1.0 +/- 0.5 mm. The FDMA was classified into 3 groups of variants based on its relationship with the first dorsal interosseous muscle. The groups were identified as the superficial artery (54.5%), intramuscular artery (39.6%), and submuscular artery (9%) variants. The rates of visualization of the distal and proximal portions of the FDMA were 86.6% and 47%, respectively. In the first intermetatarsal space, there were anastomoses between the FDMA and the first plantar metatarsal arteries in 87.6% of the feet. CONCLUSIONS: The FDMA varies greatly; however, sonography can clearly show its morphologic characteristics, such as caliber and location. Sonography also provides valuable preoperative information in microsurgery of the foot.

Adolescent↗

PubMed1998

Phalangeal cone-shaped epiphyses of the hand: their natural history, diagnostic sensitivity, and specificity in cartilage hair hypoplasia and the trichorhinophalangeal syndromes I and II.

Phalangeal cone-shaped epiphyses are an ideal object for the radiologist to study with temporal reasoning, to examine their shape, diagnostic usefulness, natural history and effect on pathophysiology. Radiographs of the hands of 60 patients with cartilage hair hypoplasia (CHH), 69 with trichorhinophalangeal syndrome I (TRP I) and 11 with TRP II were examined, including 26 longitudinal observations. The early phases of cone development were recorded. In CHH a characteristic mesophalangeal type of cone in 42/47 patients of the "Age Suitable for Classification" (ASC) was detected. All 46 TRP I and 9 TRP II patients in the ASC had the previously described mesophalangeal cone type 12. However, 1/4 of these TRP I and all TRP II cases presented a milder variant of type 12: type 12 A. A complex sequence of secondary changes in the proximal interphalangeal joints in TRP I leading eventually to subluxation was recorded. It can be concluded that in the ASC the cones described are highly sensitive but not specific diagnostic indicators. In infancy and early childhood, other phalangeal changes were found, which may be of diagnostic help.

Adolescent↗

PubMed2004

Lessons from genetic profiling in soft tissue sarcomas.

Soft tissue sarcomas represent a heterogeneous group of tumors and include over 50 histotypes. Some of these tumor types are characterized by specific chromosomal translocations, whereas other types show complex genetic aberrations. The recent developments within gene expression technologies have now been applied to studies of soft tissue sarcomas (STS) and the first results indicate that genetic signatures are useful for classification and diagnosis. Distinctive expression profiles have been found in e.g. gastrointestinal stromal tumors (GISTs), synovial sarcomas, malignant peripheral nerve sheath tumors (MPNSTs), and in subsets of liposarcomas. The more pleomorphic tumor types, such as high-grade variants of leiomyosarcomas, malignant fibrous histiocytomas (MFHs), fibrosarcomas, and subtypes of liposarcomas, show a greater variability among the expression profiles, but interestingly subsets with distinctive expression profiles can be identified also among these tumors. The data available place many of the genes hypothesized to be involved in the development of a certain type of STS, such as the KIT gene in GIST development, among the top discriminating genes. Thereby expression profiling provides novel insights into the pathogenesis of STS. Although much work remains to be done to validate the data and to define optimal discriminating gene lists, the current lessons from gene expression studies in STS are encouraging and imply that genetic signatures may serve as diagnostic and prognostic markers and may help identify novel therapeutic strategies.

Chromosome Aberrations↗

PubMed2004

My approach to oncocytic tumours of the thyroid.

The traditional approach to oncocytic thyroid lesions classified these as a separate entity, and applied criteria that are somewhat similar to those used for follicular lesions of the thyroid. In general, the guidelines to distinguish hyperplasia from neoplasia, and benign from malignant were crude and unsubstantiated by scientific evidence. In fact, there is no basis to separate oncocytic lesions from other classifications of thyroid pathology. The factors that result in mitochondrial accumulation are largely unrelated to the genetic events that result in proliferation and neoplastic transformation of thyroid follicular epithelial cells. The concept of classifying oncocytic lesions, including follicular variant papillary carcinomas, based on nuclear morphology, immunohistochemical profiles, and molecular markers may pave the way for a better understanding of the biology of oncocytic lesions of the thyroid.

Adenoma, Oxyphilic↗

PubMed2001

Lunate plasty for Kienböck's disease: use of a pedicled vascularised radial bone graft combined with shortening of the capitate and radius.

We treated eight patients with Kienböck's disease (two patients each with stage 1, 2, 3a and 3b disease by Lichtman's classification) by removing a pedicled, vascularised bone segment from the dorsal aspect of the distal radius and engrafting it into the lunate. Additional shortening of the radius was performed in patients with the ulna-minus or null variant. Shortening of the capitate and capito-hamate fusion were also performed in patients with stage 3 disease. All patients were relieved of their wrist pain at rest and during movement, and the mean grip strength increased from 37% of that in the contralateral hand before surgery to 80% after surgery. The mean post-operative range of motion in the affected wrist was 92% of that in the opposite wrist in patients with stage 1 and 2 disease, and 53% in patients with stage 3 disease. Post-operative assessment revealed that four patients had excellent results, three had good results, and one had a fair result.

Adult↗

PubMed2006

Large-cell neuroendocrine carcinoma of the lung.

BACKGROUND: Large-cell neuroendocrine carcinoma (LCNEC) of the lung displays morphologic and immunohistochemical characteristics common to neuroendocrine tumors and morphologic features of large-cell carcinomas. Because surgical resection of LCNEC in many series has been described with 5-year actuarial survival that is far worse than that reported for other histologic variants of non-small-cell lung cancer (NSCLC), considerable debate has emerged as to whether these tumors should be classified and treated as NSCLC or small-cell lung cancer. METHODS: The initial evaluation and diagnosis, tumor classification, surgical treatment, results of therapy, and long-term prognosis of patients with LCNEC based on our experience are discussed, and a review of the literature is presented. RESULTS: Patients with LCNEC are more likely to develop recurrent lung cancer and have shorter actuarial survival than patients with other histologic types of NSCLC, even in those with stage I disease. CONCLUSIONS: Accurate differentiation of LCNEC from other types of NSCLC is important because it identifies those patients at highest risk for developing recurrent disease. Efforts to identify effective adjuvant therapies are needed to improve treatment outcomes with this aggressive type of lung cancer.

Carcinoma, Large Cell↗

PubMed2006

Update on pancreatic endocrine tumors.

Endocrine tumors of the pancreas represent 1% to 2% of all pancreatic neoplasms. The tumors tend to have an indolent behavior, and long-term survival is common. There is no gender or age predilection. Patients can present with symptoms due to hormonal excess or a local mass effect or be asymptomatic. The tumors tend to be solid and well circumscribed. Typical microscopic findings include an organoid pattern of growth, with cells containing scant to moderate amounts of cytoplasm, and nuclei with dispersed chromatin and inconspicuous nucleoli. The morphologic spectrum of these tumors can be variable, and the differential diagnosis includes chronic pancreatitis with neuroendocrine hyperplasia, ductal adenocarcinoma, solid pseudopapillary tumor, acinar cell carcinoma, and pancreatoblastoma. The classification of these tumors remains controversial, and prognosis is difficult to predict, but important features include metastasis and invasion of adjacent structures. Resection remains the mainstay of surgical treatment. It is important to be aware that unusual morphologic variants of pancreatic endocrine tumors are common, and immunohistochemical stains can help avoid misdiagnosis.

Adenoma, Islet Cell↗

PubMed1999

[Characteristics of the mitochondrial genome of russian germans].

Nucleotide sequences of the mitochondrial DNA (mtDNA) control region were studied in Germans living in the Altai, Russia. Although this ethnic group has been living in Russia for a long time, the obtained data indicate that its mitochondrial gene pool retains the main characteristics of the Western and Central European gene pools. Regarding the mitochondrial gene pool, Russian Germans were more similar to Germans living in Germany than to Russians with regard to the frequency of the Cambridge nucleotide sequence, frequencies and composition of five European haplotypic groups (classification of Richards et al.), and average intra- and interpopulation pairwise nucleotide differences. However, the mitochondrial gene pool of Altaian Germans also differed from that of Western European populations. The gene pool of Altaian Germans contained the ancestral variants of the main haplotypic groups. To date, these variants have not been found in modern Western and Central European populations, which is apparently due to their lower frequencies. In addition, some previously unknown mtDNA variants with specific nucleotide substitutions were found in Altaian Germans. The obtained results suggest that the modern mitochondrial gene pool of Europeans, including Germans from Germany, was largely affected by the demographic processes that occurred in the past two centuries. The Germans that lived in Russia were relatively isolated and, hence, retained more characteristics of the ancestral gene pool.

DNA, Mitochondrial↗

PubMed1989

[Immunologic variants of acute lymphoblastic leukemia in adults and its correlation with cytochemical and various clinical parameters].

The authors provide data pertaining to the immunological phenotyping in the panel of monoclonal antibodies to various differentiating antigens of the leukemic cells in 27 patients with acute lymphoblastic leukemia (ALL). Based on the composition of the differentiating antigens of the leukemic cells the following immunological variants of the disease were identified: pre-B, pre-T and T-ALL--the thymic and mature (activated) ones. The phenotype was compared with the cytochemical parameters of the lymphoblasts of the identified immunological variants of ALL and with some clinical and hematological manifestations of the disease. The comparison of the data obtained during blast cell immunophenotyping with the cytochemical parameters and some clinicohematological findings suggests the development of a more fundamental classification of ALL in order to perfect the treatment of the patients suffering from ALL.

Adolescent↗

PubMed1984

[Clinico-morphological characteristics of renal-cell carcinoma].

One hundred and fifty patients aged 19 to 79 years operated on for renal-cell carcinoma in 1978-1982 were examined. In 46% of the patients tumour was confined to the kidney, in 30%, it grew into the perirenal fat, and in 18.7%, into the renal veins, in 11.3%, there were metastasis to the regional lymph nodes and in 8%, remote metastasis. Morphologically, tumours were verified according to the classification by N. A. Kraevsky et al.: clear-cell carcinoma was diagnosed in 50.7%, granular-cell carcinoma in 12.7%, sarcoma-like carcinoma in 4.7%, adenocarcinoma in 13.3%, mixed-cell carcinoma with signs of different variants in 18.7% of patients. The morphological picture was compared to the angiographic and main clinical data; the frequency of tumour growth into the fibrous capsule of the kidney and vein and the incidence of metastasis were established for various morphological types of tumour. The incidence of these parameters is not similar at different morphological types, thus it is possible to distinguish different clinicomorphological variants of renal-cell carcinoma.

Adenocarcinoma↗

PubMed1982

Principles of rational classification and nomenclature of human influenza A viruses.

To eliminate possible mistakes in the new nomenclature of influenza A viruses, approved by the WHO influenza experts Committee on February 1980, it is suggested to introduce the following changes: reestablish the independent position of subtypes of human influenza A viruses with hemagglutinins HSw1, HO and H1 and neuraminidase N1; use as a principle method for differentiation of various subtypes the hemagglutination inhibition (HI) test instead of the double immunodiffusion test (DIDT); to strengthen the leading role of the host in the classification of influenza A viruses by presenting human influenza viruses separately from the animal and avian viruses; it is advisable to change the present classification of influenza viruses by dividing the family of orthomyxoviridae into two species - Influenza A virus and Influenza B virus and promoting the existing influenza A virus subtypes into the rank of a serotype and the main antigenic variants within each type - into subtypes.

Animals↗

PubMed1995

[Clinical significance of alkaline phosphatase isozyme analysis].

Six bands with alkaline phosphatase (ALP) activity can be detected by electrophoresis using cellulose acetate membrane. From the anodic side, they are high molecular weight ALP (ALP1), hepatic ALP (ALP2), bone ALP (ALP3), placental ALP (ALP4), intestinal ALP (ALP5) and IgG bound ALP (ALP6). Variant ALP (ALP1) can also be detected by the use of polyacrylamide gel. Identification or quantitative measurement of each isozyme is possible by using heat inactivation, various inhibitors, gel filtration, immunoassay, etc. This report describes the method of classification of ALP isozymes, the clinical significance of each isozyme, and change in ALP isozymes in various pathological states.

Alkaline Phosphatase↗

PubMed1997

[Cyclic nucleotide phosphodiesterases: diversity, classification, structure and function].

During the last years there have been major advances in the knowledge of cyclic nucleotide phosphodiesterases. Particularly, referred to the presence of multiple different isozymes. Seven different phosphodiesterase gene families, have been described in mammalian tissues, containing several distinct genes, most of them expressed in different tissues as functionally unique splice variants. This article includes various aspects of the currently accepted nomenclature, structure and function of each family of phosphodiesterases. Finally, a brief discussion of the presence and role of these enzymes in the cell proliferation and differentiation processes, in parasites of the Trypanosmatidae family, is provided.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗