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At least 379 records · Page 21Linked to original sources

Letter-position coding in random constant arrays.

The processing of letter-position information in randomly arranged consonant strings was investigated using a masked prime variant of the alphabetic decision (letter/nonletter classification) task. In Experiment 1, primes were uppercase consonant trigrams (e.g., FMH) and targets were two uppercase Xs accompanied by the target letter or a nonletter (e.g., XMX X%X). Response times were systematically faster when target letters were present in the prime string than when target letters were not present in the primer string. These constituent letter-priming effects were significantly stronger when the target letter appeared in the same position in the prime and target stimuli. This contrast between position-specific and position-independent priming was accentuated when subjects responded only when all the characters in the target string were letters (multiple alphabetic decision) in Experiment 2 and 3. In Experiment 4, when prime exposure duration was varied, it was found that position-specific priming develops earlier than position-independent priming. Finally, Experiment 5 ruled out a perceptual-matching interpretation of these result. An interpretation is offered in terms of position-specific and position-independent letter-detector units in an interactive-activation framework.

Humans↗

[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↗

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↗

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↗

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↗

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

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

Adolescent↗

[Alloalbuminemia. Description of a case].

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

Aged↗

[Acute and sudden sensorineural hearing loss].

Current views on neurosensory hypoacusis necessitate clear definitions and distinctions between acute and sudden hypoacusis as independent nosological entities of hearing defects. Sufficient data available make it possible to characterize the above forms clinically, etiologically and pathogenetically. Common views of many Russian ENT specialists on sudden and acute hypoacusis as the same entity complicate solving the problem of neurosensory hearing disorders. Orderly classification of acute and sudden hypoacusis variants and subgroups will encourage differentiated and sound approach to treatment of neurosensory hearing loss.

Acute Disease↗

Ins405AsnPro mutation in the von Willebrand factor propeptide in recessive type 2A (IIC) von Willebrand's disease.

The molecular defects of the von Willebrand factor (vWF) have been studied in the patient in whom the von Willebrand disease phenotype IIC was originally described. A six nucleotide insert, AATCCC, was found in exon 11 of the vWF gene, predicting the insertion of the amino acids asparagine and proline between phenylalanine 404 and threonine 405 of the vWF propeptide. The mutation was present in one allele. Analysis of amplification products derived from platelet vWF mRNA showed the other allele to be silent. The patient is thus a compound heterozygote for a null allele and the IIC allele, in accord with the recessive mode of inheritance of the IIC phenotype. Family studies indicated the IIC mutation to have occurred de novo, possibly as a result of a duplication event. In vitro mutagenesis and expression in COS-7 cells confirmed the detrimental effect of the mutation on vWF multimer assembly. Taken together with those of earlier studies the present findings suggest that the IIC phenotype may well be exclusively caused by mutations which result in changes of the amino acid sequence in certain regions of the vWF propeptide. Although in the recently revised classification of von Willebrand's disease variants, the IIC type is included in the 2A category, obviously it constitutes a very distinct subtype.

Animals↗

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↗

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↗

[The Mirizzi syndrome--from the first description until today].

Pablo Luis Mirizzi was the first to describe an obstructive jaundice caused by compression of the common hepatic duct by the stone in the cystic duct or the neck of the gallbladder in 1948. McSherry et al in 1982. described a new type of Mirizzi's syndrome calling it type II. Csendes et al in 1989. gave a new classification in four types. According to it, type II of Mirizzi's syndrome was devided in three types depending on the size of the destruction of the common hepatic duct. We previously described a subtype of Mirizzi's syndrome in which besides very wide cholecystohepatic fistula, a combined fistula with duodenum was developed. Nagakawa et al in 1997. described a new type of Mirizzi's syndrom and gave their classification of syndrome in four types. In the present article the authors proposed a combined classification which takes into account not only all described variant of the syndrome but possibilities of operative reconstruction. Type I would be the same as in all previous classifications. Type II would correspond to the cholecystohepatic fistula in which a primary repair is possible. Type III would correspond to the cholecystohepatic fistula in which a primary repair is not possible so that biliodigestive anastomosis has to be carried out. Subtype IIIa would correspond to the same situations but complicated with fistula with the duodenum which has to be repaired as well. A Type IV of Mirizzi's syndrome would correspond to the inflammatory obstruction of the common hepatic duct as described by Nagakawa et al.

Cholelithiasis↗

Diffuse large B-cell lymphoma: a heterogeneous group of non-Hodgkin lymphomas comprising several distinct clinicopathological entities.

Diffuse large B-cell lymphoma (DLBCL) as defined by the World Health Organization (WHO) classification is clinically, morphologically and genetically a heterogeneous group of malignant proliferations of large lymphoid B cells. Over the last 6 years, several studies have been published improving our understanding of these lymphomas. These studies analyzed DLBCL by their gene expression profile, provided further information on some of the variants of DLBCL listed in the WHO classification and stressed the impact of the site of origin of these tumors. This review summarizes these recent data and explores their impact on the recognition of new clinicopathological lymphoma entities.

B-Lymphocytes↗

The S.//.A.IG amino acid motif is present in a replication dependent late H3 histone variant of P. lividus sea urchin.

A novel gene encoding a new H3 histone varian (H3L) has been identified in P. lividus sea urchin embryo. It encodes a H3 histone protein showing the S.//.A.IG amino acid motif typical of the replication independent H3.3 variants but in a mRNA showing the 3' terminal stem-loop nucleotide sequence that is typical of the replication dependent variants. The gene is intronless, the corresponding short transcript is non-polyadenyl ated and its expression is replication dependent with a timing of late variant. The new H3 variant is expressed as a minor component with respect to a major replication dependent late H3 histone here identified by partial cDNA sequence. These results show that classification of histones in replication dependent and independent variants only on the basis of their amino acid sequences should be reconsidered.

Amino Acid Sequence↗

Prepubic dermoid sinus: possible variant of dorsal urethral duplication (Stephens type 3).

The authors present the case of 4-month-old girl with a midline prepubic sinus extending from the skin overlying the pubis to the superior surface of the bladder, and continuing to the umbilicus via the median umbilical ligament. The distal portion of the exicised sinus was surrounded by concentric bundles of collagen and smooth muscle with minimal inflammatory infiltrates, which suggests a developmental origin. According to Stephens' classification, the sinus appears to be a variant of dorsal urethral duplication of Stephens type 3.

Cutaneous Fistula↗

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↗

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

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

Adult↗