PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Variant interpretation”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources

Visibility of the central canal on MRI.

The central canal of the spinal cord is present at birth and becomes progressively obliterated. Cadaver studies have shown that it may persist partially or completely. To our knowledge, this entity has not been described on MRI. We reviewed 794 MRI studies of the spinal cord, and found 12 patients (aged 14 to 65 years) who had an intramedullary cavity. The cavity was at the junction of the ventral 1/3 and dorsal 2/3 of the spinal cord, except at the level of the lumbar enlargement, where it was central. It was filiform in most cases, although sometimes fusiform (3 to 4 mm in diameter), and had regular contours. The cavity were thoracic in 69 % of cases. The clinical features were totally unrelated to the image, and there were no anatomical factors (Chiari malformation, dysraphism) predisposing to syringomyelia. The images were perfectly compatible with a persistent central canal, which we interpret as a variant of normal anatomy. Therefore it is important to regard these findings as normal, to avoid unnecessary treatment and follow-up.

Adolescent↗

Angiosarcoma of the thyroid: a light, electron microscopic and histoimmunological study.

A histologic, histoimmunological, and ultrastructural study of a primary angiosarcoma of the thyroid gland is reported. The occurrence of neoplastic cells positive for Factor VIII-related antigen and Ulex Europaeus Agglutinin-I and the presence in their cytoplasms of Weibel-Palade bodies are consistent with this diagnosis. These findings further support the view that primary angiosarcoma of the thyroid is a distinct pathological entity and should no longer be interpreted as a variant of a poorly differentiated carcinoma.

Aged↗

Association of mis-sense substitution in SRD5A2 gene with prostate cancer in African-American and Hispanic men in Los Angeles, USA.

BACKGROUND: Prostate cancer is a very common disease in more-developed countries, but its cause is largely unknown. It is an androgen-dependent cancer, and androgens have been proposed as having a substantial role in predisposition to the disease. Thus, variations in androgen metabolism genes may affect risk of this disease. METHODS: We screened 216 African-American and 172 Hispanic men with prostate cancer, and 261 African-American and 200 Hispanic healthy men (controls), from a large prospective cohort study (the Hawaii-Los Angeles Multiethnic Cohort Study) for a mis-sense substitution in the human prostatic (or type II) steroid 5alpha-reductase (SRD5A2) gene, the product of which controls metabolic activation of testosterone to dihydrotestosterone. This mis-sense substitution results in an alanine residue at codon 49 being replaced with threonine (A49T). We also reconstructed this mutation in the SRD5A2 cDNA, and overexpressed the enzyme in mammalian tissue culture cells. FINDINGS: The A49T aminoacid substitution in the SRD5A2 gene increased the risk of clinically significant disease 7.2-fold in African-American men (95% CI=2.17-27.91; p=0.001) and 3.6-fold in Hispanic men (1.09-12.27; p=0.04). The mutant enzyme had a higher in-vitro Vmax than the normal enzyme (9.9 vs 1.9 nmol min(-1) mg(-1)). INTERPRETATION: The A49T variant of the SRD5A2 gene may be a significant contributor to the incidence of prostate cancer in African-American and Hispanic men in Los Angeles. We estimate that the population attributable risk due to this aminoacid substitution for clinically significant disease is about 8% in both populations. Increased conversion of testosterone to dihydrotestosterone catalysed by this variant steroid 5alpha-reductase enzyme may be the cause of the increased risk.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

Unusual variants of the tributaries of the main pancreatic duct revealed by postmortem and endoscopic pancreatography.

Analysis of 97 human postmortem pancreatograms and 103 endoscopic pancreatograms revealed a total of 3 cases (1.5%) with isolated variants in the branches of the main pancreatic duct. In the first one, tortuous branches were present in the upper head-body region. The second case involved joint tributaries bridging over an unstenosed segment of the main pancreatic duct. In the third case, we found three branches from the uncinate process running down to the main duct. In all of these cases no pathological substrate was found, and they should be considered as anatomical variants observed during interpretation of a radiogram.

Adult↗

Identification of multiple quantitative trait loci linked to prion disease incubation period in mice.

Polymorphisms in the prion protein gene are known to affect prion disease incubation times and susceptibility in humans and mice. However, studies with inbred lines of mice show that large differences in incubation times occur even with the same amino acid sequence of the prion protein, suggesting that other genes may contribute to the observed variation. To identify these loci we analyzed 1,009 animals from an F2 intercross between two strains of mice, CAST/Ei and NZW/OlaHSd, with significantly different incubation periods when challenged with RML scrapie prions. Interval mapping identified three highly significantly linked regions on chromosomes 2, 11, and 12; composite interval mapping suggests that each of these regions includes multiple linked quantitative trait loci. Suggestive evidence for linkage was obtained on chromosomes 6 and 7. The sequence conservation between the mouse and human genome suggests that identification of mouse prion susceptibility alleles may have direct relevance to understanding human susceptibility to bovine spongiform encephalopathy (BSE) infection, as well as identifying key factors in the molecular pathways of prion pathogenesis. However, the demonstration of other major genetic effects on incubation period suggests the need for extreme caution in interpreting estimates of variant Creutzfeldt-Jakob disease epidemic size utilizing existing epidemiological models.

Animals↗

Identification and topology of variant sequences within individual repeat domains of the human epithelial tumor mucin MUC1.

This study shows for the first time that the tandemly repeated icosapeptide of human MUC1 underlies a genetic sequence polymorphism at three positions (underlined): PDTRPAPGSTAPPAHGVTSA. The concerted replacement DT-->ES (sequence variation 1) and the single replacements P-->Q (sequence variation 2), P-->A (sequence variation 3), and P-->T (sequence variation 4) were identified by sequencing of polymerase chain reaction products and studied by minisatellite variant repeat analysis for their incidence and topology in the 5' and 3' peripheral regions of the variable number of tandem repeats domain. Minisatellite variant repeat analyses were performed with 27 individual samples of genomic DNA from human cells and tissues covering 30-60% of the domain. Within the peripheral regions, sequence variations 1-4 occur at high incidence and show a nearly constant repeat topology in all individual normal and tumor samples. Also, individuals who were non-Caucasian or of different ethnic background were found to have the same set of replacements with identical topology. The repeat variant 1 replacing the established tumor target motif DTR with ESR was found in all individuals and appears predominantly in repeat clusters (diads and triads). The largely constant topology of variant repeats is interpreted by the assumption that the variable number of tandem repeats domain has evolved as a recent expansion of sequence variable super-repeats.

Alleles↗

Factor VIII-related antigen in malignant hemangioendothelioma of the thyroid: additional evidence for the endothelial origin of this tumor.

Malignant hemangioendothelioma of the thyroid gland, which most often originates in a hemorrhagic nodule, is a well-known entity in European alpine regions with endemic goiter. In other parts of the world it very rarely has been diagnosed. This tumor may display considerable morphologic variation and often has been interpreted as a variant of undifferentiated carcinoma. In 13 out of 20 thyroid tumors, classified by light microscopy as malignant hemangioendothelioma, Factor VIII-related antigen, a marker for endothelial cells, was demonstrated in neoplastic cells with the help of immunohistochemical technics applied to conventional paraffin sections. In one case, in which material suitable for electron microscopy was available, Weibel-Palade bodies were found in tumor cells. These findings add strong support to the notion of an endothelial origin of this neoplasm.

Aged↗

Pulmonary metastases (with admixed epithelial elements) from smooth muscle neoplasms. Report of nine cases, including three males.

This study pertains to an entity characterized by the presence of multiple intrapulmonary nodules, which consist of an admixture of bundles of well-differentiated smooth muscle cells and epithelial-lined spaces. These lesions have been frequently interpreted as a variant of hamartomas. However, in this review of the literature, and careful analysis of nine cases of this entity, we concluded that they should be considered metastases from smooth muscle tumors which incorporate some structures of mature lung parenchyma as they slowly expand. We affirm that the designation "fibroeliomyomatous hamartoma" should be discarded. Our cases occurred in six female and three male patients. In all but one female the primary source for lung metastases was uterus, while the male patients had primary lesions in the saphenous vein, diaphragm, and soft tissues. These lung lesions increase in size and number and are potentially fatal, though this may take many years. Even though the smooth muscle cells of the lung nodules appear bland on light microscopy, we were always able to demonstrate mitotic activity; electron microscopy indicated immaturity of the cells. For these reasons, we believe the tumors to represent metastatic leiomyosarcomas.

Adult↗

Meyerson phenomenon within a nevus flammeus. The different eczematous reactions within port-wine stains.

Only few reports about eczematous reactions overlying nevi flammei exist. All of them were observed in children. The description of an eczematous reaction within a congenital nevus flammeus on the left lower leg of a male adult gives reason to discuss this rare phenomenon. Eczema or inflammatory changes within a port-wine stain may mostly be a collision dermatosis with an atopic dermatitis, especially when they arise in children and are localized to the neck and face. When they are observed within a grossly visible vascular malformation, as for example in the Klippel-Trenaunay syndrome, they may have a pathogenesis similar to stasis dermatitis. In rare cases, an eczematous reaction within a nevus flammeus may be the result of genetic mosaicism and is interpreted as a variant of the so-called Meyerson phenomenon.

Humans↗

Primary structure of mouse and rat nephrin cDNA and structure and expression of the mouse gene.

Nephrin is a central component of the glomerular podocyte slit diaphragm and is essential for the normal renal filtration process. This study describes the complete structure of the mouse nephrin gene, which was shown to be homologous to the human gene, the major difference being 30 exons in the mouse gene as opposed to 29 in human. The complete primary structure of mouse and rat nephrins was also determined. The sequence identity between the mouse and rat proteins was shown to be 93%, while both rodent proteins have only about 83% sequence identity with human nephrin. The availability of the three mammalian sequences is significant for the interpretation of sequence variants and mutations in the nephrin gene in patients with congenital nephrotic syndrome. In situ hybridization analyses of whole mouse embryos and tissues revealed high expression of nephrin in kidney glomeruli and, surprisingly, an intense and highly restricted expression in a set of cells in hindbrain and spinal cord. No expression was observed elsewhere. This expression pattern may explain occasionally occurring neural symptoms caused by inactivating mutations in the nephrin gene in patients with congenital nephrotic syndrome.

Animals↗

Morphological nature of the atrioventricular valves in hearts with double inlet left ventricle.

The rudimentary right ventricle in hearts with double inlet to a dominant left ventricle can exist either to the right or the left side of the ventricular mass. These variants have been interpreted to imply differences in ventricular topology. If correct, they also imply that differences should exist in the morphology of the atrioventricular valves, previously thought to be indistinguishable one from the other. To test this possibility, we examined 15 hearts with double inlet to a morphologically left ventricle and 10 normal hearts. The distinguishing features of normal valves were evaluated for their consistency, and the most reliable were employed for interpreting the valves in the abnormal hearts. As shown by previous echocardiographic studies, insertion of valvar tension apparatus to the interventricular septum was unique to the morphologically tricuspid valve. Ten of the abnormal hearts had one valve showing this feature, it being absent in the other valve. The attachment, consistently on the same side as the rudimentary right ventricle, could be of diagnostic value in determining ventricular topology. In our small study, nonetheless, this approach still leaves one third of the hearts in which topology cannot be ascertained with certainty and in which it is not possible to distinguish the morphological nature of the atrioventricular valves.

Echocardiography↗

Systematic common and rare variant association testing in 392,030 whole genomes in All of Us.

Large-scale genome-wide association studies (GWAS) and rare variant association studies (RVAS) from population biobanks provide valuable resources for gene discovery in complex human traits. We present an analysis of the All of Us Research Program v8 release, which includes whole genome sequencing data and harmonized phenotypic information of 392,030 participants after quality control, enabling a unified investigation of rare and common variants across a spectrum of human traits and diseases. We build an extensive phenome- and genome-wide ("All by All") computational framework to perform GWAS and RVAS on 3,602 phenotypes and identify 49,863 approximately independent, high-quality single-variant and gene-level associations. Meta-analyses of All of Us and UK Biobank, with sample sizes as large as 786,871 participants, further enhance statistical power and find 193 pLoF gene-phenotype associations that are not significant in either cohort alone, including 22 associations not highlighted by previous studies. We also present a public interactive browser that integrates association results for common and rare variants to facilitate interpretation and rapid querying of summary statistics, along with supporting documentation, and a Featured Workspace in the All of Us Researcher Workbench. Our framework will apply to iterative data releases as All of Us grows, empowering researchers worldwide to uncover insights into the functional effects of genetic components on complex traits and diseases.

Journal Article↗

Analysis of relative binding affinity of E7-pRB of human papillomavirus 16 clinical variants using the yeast two-hybrid system.

A number of genotypes of the human papillomaviruses (HPV) are associated with malignancies of the uterine cervix. Sequencing work has revealed the existence of intratype HPV variants with minor differences in the nucleotide sequence. More recent data suggest the possibility that some of the variants may have different modes of clinical manifestation. In this study, sequences of the E6 and E7 oncogenes of 17 HPV16 isolates derived from PAP smear samples of Taiwanese patients were analyzed. A number of E6 and E7 novel variants were found. Particularly, a prevalent (64.7%) E6 polymorphic site A442C with an E113D amino acid substitution seems specific to Taiwanese patients. In E7, two novel but silent polymorphic sites G663A (41.2%) and T846C (88.2%) were also prevalent in the samples analyzed. The yeast two-hybrid system was adopted for rapid assessment of relative E7-pRb binding affinity in the variants. The relative binding affinities of the E7 proteins of different HPV types to pRB were in close agreement with previous biochemical data. A T663G/C24W polymorphic change in E7 correlated with a decrease in E7-pRb relative binding affinity the significance of which remains to be clarified. This semi-quantitative biochemical and genetic approach may be useful as a first step in the development of clinical protocols for the screening and identification of important HPV variants for clinical interpretation and for further functional analysis by transfection or other bioassays.

Female↗

[Evolution of epidemiology].

The emergence, formation and stages of the development of today epidemiology of infectious diseases are analyzed. Differences in views concerning the essence of epidemiology as science between Russian and foreign schools are indicated. The brief description of the main stages in rendering basic concepts of Russian epidemiology more extensive and profound, including the gradual alteration of the view on epidemiology as the science dealing only with the epidemic process, is presented. In this connection new data on the epidemiological specificity of zoonotic, and especially sapronotic infections, leading to an essenmtal correction of the main postulates of epidemiology, are analyzed. Broader notions of the reservoirs of the causative agents of infections are given, the discrete character of the epidemic (epizootic) process, the role of the latent forms of bacteria in their preservation both in the environment and in the human body in the course of the infectious process are postulated. The complexity of the term "emerging infections" is discussed and 3 variants of its interpretation are proposed. The increasing role of anthropogenic factors, including technogenic effects, is emphasized; in future these factors may be capable of accelerating the man-made evolution of epidemiology.

Animals↗

[Increased risk of death from coronary heart disease in men with low blood concentration of total cholesterol and low density lipoprotein cholesterol according to data from a prospective epidemiologic study in Moscow and Leningrad within the framework of Soviet-American cooperation].

The authors provide the results of a prospective study carried out for almost 10 years among men who underwent screenings in 1975-1977 at an age of 40-59 years in Moscow and Leningrad (overall 6431 persons) with a purpose of analyzing potential causes of high risk of death from coronary heart disease in a group of subjects with hypocholesterolemia. Based on a mathematical-statistical analysis, variants of the interpretations of the indicated fact are presented.

Adult↗

A lineage switch in acute monocytic leukemia. A case report.

A case of congenital monocytic leukemia that underwent a lineage switch to acute lymphocytic leukemia (ALL) is described. The original leukemia had typical monocytic features, as evidenced by morphology (FAB M5), cytochemistry (nonspecific esterase) and immunophenotype (My4 positive). Cytogenetic study showed a pseudodiploid clone t(9;11)(p22;q21) that could be interpreted as a variant of the t(9;11)(p22;q23) reported in patients with the M5 type of leukemia. After successful remission induction with single-agent chemotherapy (VM-26) and subsequent sustained remission for 12 months with alternating VM-26 and VP-16-213, lineage switch to ALL (FAB L1) occurred. The presence of both lymphoid and myeloid markers on leukemic cells at lineage switch suggested the biphenotypic character of the patient's ALL. Our observation indicates that a lineage switch can occur from monocytic leukemia to ALL, although most of the cases previously reported have been in the reverse direction. This case emphasizes again the need to carry out careful and comprehensive marker studies to gain insight into the possible prognostic significance and the application of appropriate therapy.

Bone Marrow↗

[Hereditary factors and their causative role in anatomic variation].

As demonstrate the literature data and the authors' observations on the composition of the anatomical structures of the extremities at the popliteal pterigyum syndrome of Smith-Lemley-Optis, as well as at some other monogenic syndromes, the manifestation of the anatomical changeability in humans is defined, to an essential degree, by hereditary factors. A suggestion is made that investigation of the anatomical changeability in connection with genetic peculiarities of the organism makes it possible to approach the causal interpretation of the variants and the developmental anomalies and comprehend the sources of multiplicity of forms and structure of the human organs and systems.

Chromosome Aberrations↗

[Biology of glucose-6-phosphate dehydrogenase deficiency].

G-6-PD deficiency is predominant in the entire history of haemolytic anemias secondary to enzyme deficiency, since its represents, by far, the most frequent erythro-enzymopathy; it is also the most studied and the best known from the clinical as well as biological standpoints. Because of the ethnic groups particularly affected, this deficiency is essentially, in France, an imported pathology, even if there are a few true european cases. The biological diagnosis of the deficient patient is simple and well codified, but the interpretation of numerous variants of the enzyme remains quite complex. The recent cloning of the gene should provide a decisive progress in understanding these various deficiencies.

Anemia, Hemolytic↗