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Dynamic clustering of genomics cohorts beyond race, ethnicity-and ancestry.

BACKGROUND: Recent decades have witnessed a steady decrease in the use of race categories in genomic studies. While studies that still include race categories vary in goal and type, these categories already build on a history during which racial color lines have been enforced and adjusted in the service of social and political systems of power and disenfranchisement. For early modern classification systems, data collection was also considerably arbitrary and limited. Fixed, discrete classifications have limited the study of human genomic variation and disrupted widely spread genetic and phenotypic continuums across geographic scales. Relatedly, the use of broad and predefined classification schemes-e.g. continent-based-across traits can risk missing important trait-specific genomic signals. METHODS: To address these issues, we introduce a dynamic approach to clustering human genomics cohorts based on genomic variation in trait-specific loci and without using a set of predefined categories. We tested the approach on whole-exome sequencing datasets in ten cancer types and partitioned them based on germline variants in cancer-relevant genes that could confer cancer type-specific disease predisposition. RESULTS: Results demonstrate clustering patterns that transcend discrete continent-based categories across cancer types. Functional analysis based on cancer type-specific clusterings also captures the fundamental biological processes underlying cancer, differentiates between dynamic clusters on a functional level, and identifies novel potential drivers overlooked by a predefined continent-based clustering. CONCLUSIONS: Through a trait-based lens, the dynamic clustering approach reveals genomic patterns that transcend predefined classification categories. We propose that coupled with diverse data collection, new clustering approaches have the potential to draw a more complete portrait of genomic variation and to address, in parallel, technical and social aspects of its study.

Humans↗

Genetic Contributors to Postoperative Delirium and Their Implications for Dementia Outcomes.

BACKGROUND: Postoperative delirium (POD) is a perioperative neurocognitive disorder that substantially impairs patient recovery. Unfortunately, its genetic risk profile and relationship with subsequent dementia remain unclear. This study aimed to elucidate genetic contributors to POD identified via Hospital Episode Statistics codes and to examine its association with subsequent dementia. METHODS: The study included 230,179 noncardiac and 21,254 cardiac surgery subjects from the UK Biobank, defining POD using delirium codes from the International Classification of Diseases (10th revision) recorded within the first 7 postoperative days. Genome-wide association studies were performed in the noncardiac and cardiac cohorts and their prespecified subgroups, followed by functional annotation, gene prioritization and drug-target analyses. Associations between POD and subsequent dementia were estimated using Cox models. RESULTS: In the noncardiac cohort, one genome-wide significant locus was identified at the APOE region, with rs429358 as the lead variant ( P = 5.00 × 10 -28 ). Integrative gene prioritization analyses highlighted multiple genes within this locus. Exploratory drug-target analyses suggested potential subgroup-specific drug-target enrichment. In the cardiac cohort, no genome-wide significant signals were detected. POD was associated with all-cause dementia after both noncardiac (hazard ratio, 6.45; 95% CI, 5.45 to 7.63) and cardiac (hazard ratio, 2.95; 95% CI, 1.71 to 5.08) surgeries. CONCLUSIONS: This study demonstrates APOE as a genetic risk locus for International Classification of Diseases-coded POD in the noncardiac surgery setting and confirms an association between POD and subsequent dementia.

Humans↗

The clinical significance of blast cell morphology in childhood lymphoblastic leukaemia.

The morphological classification of ALL based on the FAB co-operative group's criteria is capable of identifying 10-15% of children with L2 disease who, given similar treatment, will fare less well than the 85-90% with the L1 variant. The significant features defining L2 morphology are a low cellular nuclear: cytoplasmic ratio and the presence of nucleoli. Children with L2 disease do not have higher leucocyte counts but are older, have "common" ALL less frequently, and more often have well-preserved marrow function at diagnosis. Their poor outlook is manifest not only by their higher relapse rate but also by a higher proportion failing to remit in the first instance. L2 morphology does not necessarily "breed true" and can arise in a small proportion of patients with previous L1 disease at the time of relapse. Other striking morphological features of lymphoblasts, including azurophil granules, vacuoles and "hand mirror" cells, have yet to have their significance defined, though the latter feature may be an unfavourable finding.

Child↗

Early infantile developmental and epileptic encephalopathy: clinical spectrum, diagnosis, outcomes, and evolving treatment strategies.

Early infantile developmental and epileptic encephalopathy (EIDEE) is among the most severe epilepsy syndromes, with onset before three months of age and an estimated incidence of approximately 10 per 100,000 live births. The 2022 International League Against Epilepsy classification unified the historically distinct Ohtahara syndrome and early myoclonic encephalopathy under a single diagnostic framework defined by frequent drug-resistant tonic and/or myoclonic seizures, an abnormal neurological examination, and an abnormal interictal electroencephalogram-most characteristically a burst-suppression pattern. This narrative review synthesizes the clinical, electrophysiological, neuroimaging, genetic, and therapeutic literature within the EIDEE framework. The clinical phenotype is characterized by central hypotonia, postnatal microcephaly, cortical visual impairment, and age-dependent syndromic evolution toward infantile epileptic spasms syndrome or Lennox-Gastaut syndrome in the majority of patients. Electroencephalography remains essential for syndromic classification, while systematic metabolic screening and early trio whole-exome or whole-genome sequencing are central to the etiologic workup, achieving diagnostic yields of 60-65%. The most commonly identified genetic causes include STXBP1, KCNQ2, and SCN2A variants. Outcomes are poor overall and strongly etiology-dependent: vitamin-responsive disorders carry a substantially more favorable prognosis, whereas mortality reaches 25% in genetic cohorts. Genotype-guided pharmacotherapy is now applicable to a clinically meaningful subset of patients, with sodium channel blockers, potassium channel openers, and emerging antisense oligonucleotide therapies representing important therapeutic advances. Gene therapy trials are underway but have encountered early safety signals, underscoring the vulnerability of this population. Critical unmet needs include earlier molecular diagnosis, precision therapies targeting developmental outcomes beyond seizure control, and prospective international registries to characterize the long-term natural history of EIDEE.

Humans↗

[Target epitopes of monoclonal antibodies against ABH structures].

Comparing the reactivities of murine and human monoclonal antibodies directed against the antigens of A, B, and H blood groups by using different techniques (agglutination, inhibition by synthetic oligosaccharides and salivary antigens, tissue immunofluorescence, the use of an anti-idiotype antibody) enabled us to show a high heterogeneity of anti-A, anti-AB antibodies and, to some extend, anti-B and anti-H antibodies. Despite this diversity, the determination of the antibody specificity thanks to synthetic antigens made it possible to distinguish several groups of anti-A, B, AB, and H antibodies and to establish a classification that takes also their reactivity towards salivary and tissue antigens into account. On the contrary, few correlations were found between these tests and the ability of antibodies to agglutinate red blood cells of the different ABO-system variants.

ABO Blood-Group System↗

Identification of two new antigenic subgroups within the genus Mobiluncus.

Classifications of 48 atypical clinical isolates of Mobiluncus spp. were determined on the basis of biochemical reactions, morphology, antigenic profiles, and DNA hybridization studies. Two new subgroups with unique antigenic profiles are described. Like typical Mobiluncus species, the antigenic variant of M. mulieris is associated with bacterial vaginosis. The atypical isolates of M. curtisii were frequently recovered from women with normal vaginal flora and were also recovered from sterile body sites. These isolates may be incorrectly identified if current biochemical and morphological criteria are used for identification. Gram stain morphology, however, correctly identifies these isolates to the species level. The characterization of these atypical isolates has important implications for future investigations in which serological methods are used for diagnosis, epidemiology, and determination of pathogenicity of Mobiluncus spp.

Antigenic Variation↗

[Liver cell carcinoma--pathomorphology and differential diagnosis].

Modern imaging techniques permit the detection of small and smaller nodular lesions of the liver. The classification and differential diagnosis of these lesions is still mainly based on pathomorphological analysis. With the exception of metastases from extra-hepatic malignant tumors, hepatocellular carcinoma is the most frequent malignant tumor of the liver. Whereas the classical variant of hepatocellular carcinoma preferentially arises in the cirrhotic liver, the fibrolamellar variant is found without association to cirrhosis and hepatitis B infection in the liver of young adults. Differential diagnosis of hepatocellular nodular lesions includes focal fatty change, focal nodular hyperplasia, liver cell adenoma, large regenerative nodules and dysplastic nodular lesions.

Adult↗

[Principles for classification of diseases of a biogeochemical nature].

The principles of working classification of human pathology associated with excess, deficiency and dysbalance of trace elements are presented on the basis of many-year analysis of the literature and own experimental and clinico-morphological observations. According to the most important variants of human contact with the environment abnormal with regard to the content of trace elements, the following types of diseases are distinguished: (1) natural, (2) technogenic, and (3) iatrogenic. In their turn, technogenic diseases are subdivided into industrial, neighbouring, transgressive. Among these diseases, monomicroelementoses and polymicroelementoses should be distinguished. The former include fluorosis, arsenosis, berilliosis, cadmium nephropathy, cobalt myocardiopathy, etc., the latter anemias of biogeochemical nature, endemic goiter, tooth caries, urolithiasis, selenium-deficient myocardiopathy, and others.

Aluminum↗

[Patterns in the spread of the vertical blood reflux in the musculo-venous "pump" of the foot in varicose disease].

An analysis of the complex clinical and phlebographic examination of 84 patients with the varicose disease was made. Eight variants of the state of the valve apparatus of profound veins of the foot were established. Main regular features of spread of the retrograde blood flow the profound veins along insufficient perforating to the superficial veins were determined. A classification of incompetence of the valve apparatus of the profound veins of the foot was developed which allows the choice of surgical procedures depending on the injury degree.

Adult↗

Cytotoxic/natural killer cell cutaneous lymphomas. Report of EORTC Cutaneous Lymphoma Task Force Workshop.

BACKGROUND: Cutaneous lymphomas expressing a cytotoxic or natural killer (NK) cell phenotype represent a group of lymphoproliferative disorders for which there is currently much confusion and little consensus regarding the best nomenclature and classification. METHODS: This study analyzes 48 cases of primary cutaneous lymphoma expressing cytotoxic proteins and/or the NK cell marker, CD56. These cases were collected for a workshop of the European Organization for Research and Treatment of Cancer Cutaneous Lymphoma Task Force, to better clarify the clinical, morphologic, and phenotypic features of these uncommon tumors. RESULTS: Several categories with different clinical and pathologic features were delineated: 1) aggressive, CD8+, epidermotropic, cytotoxic T-cell lymphoma; 2) mycosis fungoides, cytotoxic immunophenotype variant; 3) subcutaneous panniculitis-like T-cell lymphoma; 4) NK/T-cell lymphoma, nasal type; 5) CD4+, NK cell lymphoma; 6) blastoid NK cell lymphoma; (7) intravascular NK-like lymphoma; and 8) cytotoxic, peripheral T-cell lymphoma. CONCLUSIONS: Our data show that primary cutaneous cytotoxic/NK cell lymphomas include distinct groups of diseases, clinically, histologically, and biologically. Because the finding of a cytotoxic phenotype often has prognostic significance, the routine use of cytotoxic markers in the diagnosis and classification of cutaneous lymphomas should be expanded.

CD4-Positive T-Lymphocytes↗

Approaching a complete classification of protein secondary structure.

A complete classification of types of the protein secondary structure is developed on the basis of computer analysis of the crystallographic structural data deposited in the protein Data Bank. The majority of amino acid residues fall into five conformation types. A conclusion is drawn that the number of sequence variants of torsion angles phi, psi in globular proteins is limited and is essentially less than the number of possible amino acid sequences for this chain length. Along with alpha-helix and beta-structure, the distribution analysis assigning every maximum of distribution of amino acid conformations on Ramachandran map to a certain type of the secondary structure exposed a third type of the secondary structure that was previously neglected. This type of the structure is extended left-handed helical conformation, designated as mobile (M-) conformation. A full set of M-conformation fragments that seems to play a major role in protein globule dynamics has been obtained, a small radius of correlation for the polypeptide chain in M-conformation is demonstrated. It explains a prevalence of short segments of mobile conformation revealed in globular proteins. For secondary structure types, the frequency of occurrence of amino acid residues has been computed.

Amino Acids↗

Dynamic simulations of the molecular conformations of wild type and mutant xanthan polymers suggest that conformational differences may contribute to observed differences in viscosity.

Xanthan gum is an exopolysaccharide secreted by the bacterium Xanthamonas campestris whose ability to make solutions viscous at low concentrations and over a pH and temperature range have generated much interest in both academic and industrial environments. Mutant Xanthamonas strains have been derived that produce xanthan gums with an altered or variant subunit chemical structure and different measured viscosities when compared with the wild type (wt) form of the polymer. Two variant gums were targeted as potentially interesting in this study, these being the nonacetylated tetramer (natet) and the acetylated tetramer (atet), which both lack a side-chain terminal mannose residue and in one case (natet) lacks an acetate group on an internal mannose residue. Solutions of these tetrameric gums possess viscosities higher (natet) and lower (atet) than the wt gum, and therefore we have attempted to determine whether these molecules possess unique conformational preferences when compared with the wt and with each other. In this manner we can initiate an understanding of how a polysaccharide's conformation contributes to its solution properties. The GEGOP software permits a sampling of the static and dynamic equilibrium states of carbohydrate molecules, and this software was employed to calculate equilibrium states of representative oligosaccharides with chemical structures representative of xanthan-like molecules. Energy minimization techniques revealed similar local minima for all three molecules. Some of these minima are comprised of elongate backbone conformations (A type) in which side chains fold onto backbone surfaces. Other minima with A backbones possessed side chains in less intimate backbone contact especially when calculations were performed with a low dielectric constant. This phenomenon was particularly pronounced in the wt molecule where an increased number of negatively charged side-chain residues experience charge repulsion resulting in reduced side-chain-backbone contact. Metropolis Monte Carlo (MMC) dynamic simulations performed with an elevated temperature factor (1000 K) allowed a better qualitative representation of conformational space than 300 K simulations. Employing a nonhierarchical cluster analysis method (population density profile: PDP) coupled with a classification scheme, it was possible to partition resulting MMC data sets into conformational families. This analysis revealed that in simulations performed with different dielectric constant values (10, 25, and infinity) all molecules possessed primarily A-type backbones. Less elongate, more open helical backbone forms (B, C, D, J, and Flat-a) did occur during the simulations but were populated to a lesser extent. In the natet molecule significantly open helical backbones existed (E, F, G, H, and I) that did not occur in the lower viscosity wt and atet molecules. PDP clustering methods and subsequent conformational classification applied to the first residue (mannose) of the side chain permitted a determination of side-chain orientation. Comparison of all three molecules indicated a larger population of side-chain conformational families in less direct backbone contact for the wt molecule than either of the variant molecules (natet/atet) suggesting that the side chains in the wt are more flexible. Thus, a major conformational difference between the high viscosity natet and the lower viscosities of the wt/atet is the increased amount of open helical backbone in the natet. In addition, the significant difference between the higher viscosity wt and the lower viscosity atet is the increase side-chain flexibility in the wt. We hypothesize that conformational differences of this kind could form a partial explanation of the observed differences in viscosity between these xanthan-like polymers.

Carbohydrate Conformation↗

Epidemiological and antigenic analysis of respiratory syncytial virus in hospitalised Tunisian children, from 2000 to 2002.

Human respiratory syncytial virus (RSV) is the major viral cause of lower respiratory tract disease in children. Infections with the virus occur as annual winter epidemics in temperate climates, placing considerable pressure on the provision of hospital beds. Most molecular epidemiological studies have, until now, focused on isolates from infants in industrialised countries. No data have been available with regard to RSV strains from northern Africa. In this report, a recent RSV outbreak in Tunisia was studied and results showed that 176 of 815 (21.6%) nasopharyngeal aspirates collected from hospitalised children were RSV-positive by immunofluorescence assay. This RSV outbreak showed a temperature-dependent pattern (P=0.026) but no significant association with rainfall. A total of 73 RSV-positive samples were tested by two reverse-transcription-polymerase chain reaction assays (RT-PCR): RT-PCR-1, which amplifies the RNA of all RSV strains, and RT-PCR-2, which allows subgroup classification of RSV. Analysis by hybridisation assay of RT-PCR-2-amplified 1B protein gene products showed a higher prevalence of group B RSV than that of group A (82.5% vs. 17.5% among the typed strains). Knowledge of the variants is important in terms of both diagnosis and definition of a vaccine composition.

Antigens, Viral↗

Variation in the biochemical properties of the Drosophila alcohol dehydrogenase allozymes.

Thirteen Drosophila Adh variants have been characterized with respect to gene expression, substrate preference, thermostability, and specific activity. The results suggest that the variants may be grouped into two biochemical classes, typified by the properties of the two most common enzyme forms, ADH-F and ADH-S. Membership of these classes cannot be predicted from electrophoretic mobility, nor is any simple classification possible with regard to the characteristics of level of gene expression (in terms of ADH activity or ADH protein) or thermostability of the gene product.

Alcohol Dehydrogenase↗

Ophthalmoplegic migraine.

Ophthalmoplegic migraine is a rare condition, previously thought to represent a variant of migraine. Recent observations regarding its usual clinical presentation and common magnetic resonance imaging findings have given rise to speculation that this illness is more likely to represent an inflammatory cranial neuropathy. The recent revision of the International Headache Classification has reclassified ophthalmoplegic migraine from a subtype of migraine to the category of neuralgia. In this article, potential pathophysiological mechanisms are discussed. The typical clinical presentation of ophthalmoplegic migraine generally involves transient migraine-like headache accompanied by often long-lasting oculomotor, abducens or, rarely, trochlear neuropathy with diplopia and (if oculomotor nerve is involved) pupillary abnormalities and ptosis. Ophthalmoplegic migraine generally occurs in children, but a number of adult cases have been reported. Prognosis is good because symptoms almost always resolve, but, after several episodes, some deficits may persist. Differential diagnosis is rather large, although most other possible causes of ophthalmoplegia and headache have distinctive presentations or can be excluded with fairly straightforward diagnostic testing. Optimal prophylactic and acute treatment is still unclear, but migraine prophylactic medications such as b blockers and calcium channel blockers have been proposed. Steroids have been used with mixed results.

Adult↗

Cystic fibrosis mutations and genetic predisposition to idiopathic chronic pancreatitis.

Idiopathic chronic pancreatitis is a leading cause of chronic pancreatitis. Work from this and other groups has shown that idiopathic chronic pancreatitis is associated with mutations of the cystic fibrosis gene (CFTR). Many idiopathic pancreatitis patients have compound heterozygote genotypes in which both copies of the CFTR gene are abnormal. In these patients, the pancreatic disease can be viewed as a mild variant of cystic fibrosis, in which there is sufficient residual CFTR function to prevent lung disease. This article summarizes the evidence associating these abnormal CFTR genotypes with idiopathic chronic pancreatitis and reviews the implications of this association for the pathogenesis, classification, and prevention of pancreatitis.

Adolescent↗

Trisomy 6 as a primary karyotypic aberration in hematologic disorders.

We identified seven patients with hematologic disorders and trisomy 6 as the sole karyotypic aberration in bone marrow aspirates or unstimulated peripheral blood. Five patients were male and two were female; all were adults with ages ranging from 22 to 74 years. Three of the seven patients presented with manifestations of peripheral cytopenia. Their bone marrows were hypocellular with slight or no dysplastic changes and without an increase in blasts. One of these patients subsequently developed acute myeloid leukemia (AML-M1). The four remaining patients were initially diagnosed with AML--three consistent with French-American-British classification of M1 and M4 in the fourth patient. These results suggest that trisomy 6 is a nonrandom primary numerical anomaly of myeloid disorders. The association of cytopenia and hypoplastic bone marrow with trisomy 6 may constitute a new, distinctive variant among myelodysplastic syndromes.

Adult↗

On one system of methods of aphasics group rehabilitation.

One of the main and actual tasks of aphasic re-education is the development of group rehabilitation methods which contribute to the restoration of verbal communication and to the surmounting of personality problems in aphasics. In this paper, a new method for group lessons with aphasics is described. It is founded on theoretical conceptions concerning the relation between the word and its sensory basis and the problems of visual object images in aphasia. The group lesson is a system of methods including: (1) group discussion and classification of objects with a view to deblock verbal associations on the given theme; (2) drawing of objects or coding in drawing the meaning of utterances on this theme; (3) recognition of sensibilized pictures (patients' drawings). We have proposed two variants of the method: The first is to actualize the names for objects and the second one to increase the aphasics capacity for sentence making. This method was used in small therapeutic groups of aphasics and the influence of selected group factors on the patients' speech activity was studied. The described method ensures the system influence principle in the rehabilitation of aphasics.

Adult↗