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PubMedDate not supplied

Talon cusp: an overview with case reports of 3 clinical variants.

Talon cusp is a dental anomaly, which is present as an accessory cusp and is seen both in the deciduous and permanent dentition. It may occur unilaterally or bilaterally and has been reported mostly in maxillary teeth, with a few cases occurring in the mandible. Talon cusp is usually asymptomatic; however, there are many clinical problems associated with it. Talon cusp is clinically manifested in three forms: talon, semi-talon and trace talon. In this article, we present four case reports of talon cusp with an overview of different clinical variants of talon cusp, classification, etiopathogenesis, associated syndromes, clinical problems, and treatment modalities.

Adolescent↗
PubMed2006

[Urethral duplication in an adult. A case report].

Urethral duplication is a rare congenital anomaly, essentially diagnosed during adulthood. There are many anatomical variants and many, different classifications. This case report presents an uncommon form of incomplete sagittal urethral duplication with a blind intraprostatic proximal extremity. The authors discuss the value of pelvic and prostatic NMR in the work-up of this anomaly.

Adult↗
PubMed1988

[The hyperventilation syndrome].

A review of literature comprises the main data on etiological factors, pathogenetic mechanisms, clinical peculiarities and methods of diagnosis of the hyperventilation syndrome. Physicians' insufficient knowledge of this disease is emphasized. Various clinical manifestations are based on the same pathogenetic mechanisms of acute or chronic respiratory disregulation resulting in hypocapnia, a rise of vascular tone, and electrolytic disorders. Of great practical importance is the use of a unified clinical classification, of which a variant is proposed by the authors. The main therapeutic modalities are: 1) psychotherapy, 2) pharmacotherapy, 3) exercise therapy.

Affective Symptoms↗
PubMed1984

[Glucose-6-phosphate dehydrogenase deficiency and other erythrocyte enzyme abnormalities].

Normal values of glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), glutathione reductase (GR), glucosephosphate isomerase (GPI), pyruvate kinase (PK) and pyrimidine 5'-nucleotidase (P5N) have been determined in normocytes, reticulocytes, newborn cord erythrocytes, and leucocytes. Metabolic and clinical aspects of G6PD and the classification of its genetic variants are reviewed. Enzyme determinations and their variation in drug-induced haemolysis are critically presented. Extensive tables are published listing the drugs and compounds that can cause haemolysis in G6PD-deficient patients, as well as those preparations which may, probably, be administered safely. Clinical and biochemical data in patients with the inherited enzyme defects GR, GPI, PK, and P5N, as well as acquired deficiency of the last-mentioned in chronic lead intoxication, are reviewed in the light of our personal experience in this field.

5'-Nucleotidase↗
PubMed1980

Acral lentiginous melanoma.

Acral lentiginous melanoma (ALM) is a relatively recent addition to the clinicohistopathologic classification of melanomas. This variant constitutes 7 to 9 percent of diagnosed melanomas and is typified by a lentiginous macule occurring on the palm, sole, or in subungual regions. A patient with ALM arising in the subungual area and a review of the relevant literature are presented herein.

Female↗
PubMed1995

Can a specifically-aimed pathologic classification overcome the difficulties in defining HIV-associated lymphomas?

High grade B-cell systemic lymphomas in HIV-infected patients exhibit pleomorphic features as well as some overlap between established histologic subtypes thus highlighting the difficulties in defining them precisely by making use of the classifications for non-Hodgkin's lymphomas (NHL) proposed before the AIDS epidemic. A series of HIV-associated systemic lymphomas including 114 NHL and 25 Hodgkin's disease (HD) cases were morphologically and immunopheno-genotypically investigated at the Centro di Riferimento Oncologico, Aviano, Italy during a period of nine years. The International Working Formulation (WF) for NHL, the updated Kiel Classification and, later, morphologic variants of high grade B-cell NHL have been adopted in order to obtain a more detailed and specific histopathologic description of HIV-associated lymphomas. As a consequence of morphologic data, and considering also pathogenetic aspects as derived from literature, we have attempted a pathological categorization of HIV-associated systemic lymphomas based on the recognition of two main groups: the "blastic" cell group and the "anaplastic" one, both including specific cytomorphologic subtypes with, possibly, aggressive HD subtypes within one of them. This categorization uses the WF, the updated Kiel system, and the morphologic variants of high-grade lymphomas, and provides a provisional category for cases with intermediate morphologic features. Thus other histologic subtypes, such as small noncleaved cell (Burkitt) and immunoblastic lymphomas, can be defined in a more accurate way. The clear-cut placement of "anaplastic" cell lymphomas, including anaplastic large cell (CD30/Ki-1+) lymphomas, including anaplastic large cell (CD30/Ki-1+) lymphomas and possibly a proportion of HD cases, emphasizes the need for their diagnostic differentiation from polymorphic "blastic"' cell lymphomas, immunoblastic ones in particular.

Humans↗
PubMed1995

[Clinico-genetic aspects of cutaneous melanoma. I. Incidence, familial study, genetic heterogeneity].

Epidemiologic and clinical genetic data on cutaneous malignant melanoma (CMM) are presented. The incidence of CMM in Moscow from 1983 to 1987 was analyzed. Cumulative incidence (cumulative risk) was calculated for various life periods on the basis of estimates for various age groups, which were used as population frequencies. By the age of 85, these frequencies were 0.35% for males and 0.38% for females. Among relatives of patients, the incidence of CMM was 1.420 +/- 0.498% for males and 1.110 +/- 0.348% for females; i.e., the incidence exceeded the population frequency by a factor of 3 or 4. As a whole, the familial frequency of cancer was equal to 13.3% for male probands and 14.2% for female probands, i.e., more than three times higher than the population frequency. The data obtained formed the basis for the development of CMM classification. hereditary and nonhereditary variants of cutaneous melanoma were identified. Familial cases and CMM that occurred against the background of inherited disease or syndromes were classified as hereditary variants of CMM; taken together, they accounted for 38.8%. The data provided grounds for identification of families at increased risk for the development of CMM.

Female↗
PubMed2002

Towards a new understanding and classification of chondrogenic neoplasias of the skeleton--biochemistry and cell biology of chondrosarcoma and its variants.

Despite substantial knowledge on the clinicopathology of chondrogenic skeletal neoplasms, only limited insights into the biology of the different tumor variants are available. There are virtually no established molecular markers for identification and classification of these neoplasms. In this paper, we present a systematic review of the biochemistry and cell biology of chondrogenic neoplasms of the bone focussing on our own recent investigations. The hallmark of all differentiated chondrogenic tumors is the presence of neoplastic chondrocytic cells responsible for the formation of the characteristic cartilaginous tumor matrix. These cells can show the full differentiation potential of physiologic chondrocytes depending on the tumor entity investigated. The high phenotypic diversity of physiologic chondrocytes explains the previously poorly understood, striking heterogeneity of the neoplastic cells and their surrounding extracellular matrix not only between different but also within chondrogenic tumors. In our studies, tumor classifications, so far based only on histomorphological criteria, were either confirmed or corrected: mesenchymal chondrosarcomas represent the prototypic neoplasm of pre-chondrogenic undifferentiated cells undergoing multifocal chondrocytic differentiation. Enchondromas, osteochondromas, and conventional chondrosarcomas are neoplasms of multi-phenotypically differentiated chondrocytes. Clear cell chondrosarcomas appear to be neoplasms of hypertrophic chondrocytic cells. A peculiar biology is displayed by dedifferentiated chondrosarcomas, which at least in most cases show neither "anaplasia" nor "dedifferentiation", but most likely "transdifferentiation" of part of the neoplastic cells to a cellular phenotype of a different mesenchymal differentiation lineage. Chondroblastomas do not show any chondroblastic differentiation at all. Our studies delineate molecular markers of chondrogenic neoplasms of the skeleton, which have the potential to be the basis of a new biology-orientated classification of skeletal neoplasms. The expression analysis of extracellular matrix genes, in particular of the collagen types, might be able to play herein a leading role in classification and diagnosis, similar to the cytokeratin subtypes or the CDs (cluster of differentiation) for the classification and diagnosis of neoplasms of the epithelia and the lymphatics.

Animals↗
PubMed2026

Pragmatic Phenotype-Electrophysiology-Genomics Integration in Pediatric Congenital Myasthenic Syndromes: Insights From 36 Patients in a Single-Center Study in China.

AIMS: To characterize the clinical, electrophysiological, and genetic spectrum of pediatric CMS and evaluate genotype-informed outcomes using an integrated phenotype-electrophysiology-genomics approach. METHODS: We retrospectively reviewed 36 pediatric CMS patients evaluated at a single center between 2015 and 2025. Clinical features, RNS, targeted NGS/WES variants, ventilator use, treatments, ACMG/AMP classifications, and MG-ADL outcomes were analyzed. RESULTS: Of 36 patients, 28 (77.8%) developed symptoms in the neonatal period or infancy. Biallelic variants involved 17 CMS genes; postsynaptic CMS was most common (55.6%, 20/36). COLQ and CHRNE were the most frequent genes (13.9%, 5/36 each), followed by CHAT (11.1%, 4/36). VUS were detected in 19 patients (52.8%, 19/36), including 8 with biallelic VUS supported by phenotype, neuromuscular transmission findings, treatment response, and follow-up. RNS showed a ≥ 10% decrement in 16/21 tested patients (76.2%). CHAT-CMS was associated with higher ventilator use (3/4 vs. 6/32; p = 0.041) and early mortality (3/4 vs. 1/32; p = 0.002). Median MG-ADL improved from 5 to 3 after genotype-informed therapy. CONCLUSION: Pediatric CMS shows marked genetic heterogeneity and frequent VUS-related uncertainty. Integrating phenotype, electrophysiology, and genomics supports diagnosis and mechanism-guided therapy. CHAT-CMS is high risk for early respiratory failure and mortality.

Humans↗
PubMed1997

Odontogenic classification of craniopharyngiomas: a clinicopathological study of 54 cases.

Based on the striking histological similarity of craniopharyngiomas and some odontogenic tumours, we reclassified a series of 54 craniopharyngiomas (52 adamantinomatous and two papillary variants) according to the WHO classification of odontogenic tumours. Twenty-seven tumours (50%) corresponded histologically to calcifying odontogenic cyst. 13 tumours (24%) to ameloblastoma, and eight (15%) tumours showed features of both calcifying odontogenic cyst and ameloblastoma either within the same specimen or in specimens derived from different resections. Rare tumours included three cases resembling calcifying epithelial odontogenic tumour and one case resembling adenomatoid odontogenic tumour. No odontogenic counterpart could be established for papillary craniopharyngiomas. The two major subtypes, i.e. craniopharyngioma corresponding to calcifying odontogenic cyst and craniopharyngioma corresponding to ameloblastoma, did not differ in their basic clinical features. Our data confirm and extend the close histological resemblance between adamantinomatous craniopharyngioma and odontogenic tumours and cysts. Furthermore, although calcifying odontogenic cyst and ameloblastoma arising in the jaw differ in clinical presentation and outcome, our study did not reveal clinical differences for the corresponding subtypes of craniopharyngioma.

Adolescent↗
PubMed1975

[Cytological variants of lymphogranulomatosis].

It is shown that in the course of a cytological investigation it was possible not only to diagnose lymphogranulomatosis but in the overwhelming majority of cases to determine a morphological variant of the disease in accordance with Lukes et al. classification. Cytological pictures of the three histological variants of lymphogranulomatosis are described: mixed-cellular, reticular and nodular sclerosis. Cytological criteria for diagnosis of nodular sclerosis are identified.

Cytodiagnosis↗
PubMed1997

[Molecular analysis of glucose-6-dehydrogenase deficiency in Spain].

PURPOSE: G6PD deficiency is the most frequent enzymopathy-producing genetic polymorphism in humans. Up to now, over 400 putative variants of G6PD have been distinguished on the basis of biochemical characterization of the deficient enzyme. Analysis of the G6PD gene has made possible a precise classification of the G6PD molecular variants by identification of about 80 different point mutations causing much of the phenotypic heterogeneity. In the Spanish population, the analysis of G6PD has led to the identification of 15 different point mutations that underlay the phenotypic heterogeneity of G6PD previously reported by biochemical analysis. The purpose of the study has been to identify the genetic mutation responsible of the G6PD deficiency and to improve the knowledge of its genetic homogeneity. PATIENTS AND METHODS: From 50 Spanish males with G6PD deficiency 34 came from out consultation and 16 from the Spanish Study Group on Red Cell Pathology (GEHBTA-Eritropatología) The methods employed included screening of prevalent mutations by ER-PCR, SSCP-PCR, genetic segmentation and biochemical characterization of the deficient enzyme. RESULTS: In 31 cases the mutations were characteristic of the four most frequent polymorphic variants found in Spain (G6PD A-376G/202A, G6PD Mediterranean 563T G6PD Union 1360T and G6PD Seattle 344C). Since these mutations either create or abolish a specific site recognized by a restriction endonuclease (RE), they can be rapidly detected by RE digestion of a PCR-amplified product (PCR-RE). In patients where none of these mutations were present (17 cases), the G6PD gene was subjected to PCR single-strand conformation polymorphism (PCR-SSCP) analysis combined with direct PCR-sequencing. By using this procedure, 9 new mutations have been identified, five of them have been also found in other geographical areas and were associated with favism (G6PD A-376G/968C, G6PD Santamaria 376G/542T, G6PD Aures 143C and G6PD Chatham 1003A) or chronic haemolytic anaemia (G6PD Tomah 1153C). The other four mutations are unique and not reported so far: Three of them are associated with favism (G6PD Málaga 542T, G6PD Murcia 209G and G6PD Valladolid 406T) and one with chronic haemolytic anaemia (G6PD Madrid 1155G). The remaining eight cases are under study. CONCLUSION: The present study confirms the marked genetic heterogeneity of G6PD deficiency in Spain and demonstrate that the PCR-RE analysis is an easy tool for rapid diagnosis of the molecular defect in subjects with the common forms of G6PD deficiency. Furthermore the fact that G6PD A-376G/202A is the most common variant within Spanish population and the finding of G6PD Aures 43C and G6PD Santamaría 76G/542T, who are polymorphic in Algeria is consistent with a significant gene flow from Africa to Europe through Spain.

Africa, Northern↗
PubMed2006

Clinical and pathologic characteristics of focal segmental glomerulosclerosis pathologic variants.

Histologic variants of idiopathic focal segmental glomerulosclerosis (FSGS) may have prognostic value. A recent working classification system has distinguished five FSGS variants. We evaluated a cohort of adult patients with biopsy-proven FSGS diagnosed between March 1982 and July 2001 to determine if subtypes were associated with renal outcome. Renal biopsies were reviewed by two pathologists. Demographic and clinical data were obtained from charts. Outcomes were partial and complete remission of the nephrotic syndrome, and renal failure. The frequency of FSGS variants was: 3% cellular (N=6), 11% collapsing (N=22), 17% tip lesion (N=34), 26% perihilar (N=52), and 42% not otherwise specified (NOS) (N=83). Collapsing FSGS affected younger and more often black patients. Black race was uncommon in tip variant. Collapsing and tip variants had higher proteinuria and lower serum albumin than perihilar and NOS variants. Better renal function and less severe tubulointerstitial injury were observed in patients with tip variant. These patients were more likely to receive steroids and more often achieved complete remission (50%). After a median follow-up of 1.8 years, 23% of patients were on dialysis and 28% had renal failure. Collapsing FSGS had worse 1-year (74%) and 3-year (33%) renal survival compared to other variants (overall cohort renal survival at 1 and 3 years: 86 and 67%). Different histologic variants of FSGS have substantial differences in clinical features at the time of biopsy diagnosis and substantial differences in renal outcomes.

Adult↗
PubMed2025

Optical genome mapping improves clinical interpretation of constitutional copy-number gains and reduces their VUS burden.

PURPOSE: Genomic structure of copy-number gains is critical for their clinical interpretation but cannot be determined by chromosomal microarray (CMA) analysis, which does not provide information about chromosomal location and orientation of multiplied regions. We thus hypothesized that in CMA testing gains have higher probability than losses to be classified as variants of uncertain significance (VUS) and that structural information from optical genome mapping (OGM) may improve their interpretation. METHODS: Using a χ2 test, we assessed the association between classification of copy-number variants as VUS and their type (gains vs losses) in a cohort of 4073 CMA cases. Thirty-three VUS gains involving disease-associated genes were characterized by OGM to evaluate if OGM data enable their more conclusive clinical interpretation. RESULTS: The proportion of variants reported as VUS compared with likely pathogenic/pathogenic was significantly higher for gains than losses, confirming their increased VUS burden. OGM successfully determined genomic structure for all 33 copy-number gains, showing that 26 of 33 were tandem duplications and 7 of 33 were complex rearrangements. Structural information facilitated clinical interpretation in majority of the cases; it supported benign nature for 27 of 33 gains and was inconclusive or supported pathogenic role for 6 of 33. An estimated 20% of reported VUS gains would not have been reportable if we had OGM data. CONCLUSION: We illustrate a specific advantage of OGM compared with CMA: in addition to detecting both copy-number variants and balanced rearrangements, OGM improves clinical interpretation of copy-number gains by providing structural information and is thus expected to significantly decrease their VUS burden.

Humans↗
PubMed1992

Split cord malformation: Part I: A unified theory of embryogenesis for double spinal cord malformations.

Much confusion still exists concerning the pathological definitions and clinical significance of double spinal cord malformations. Traditional terms used to describe the two main forms of these rare malformations, diastematomyelia and diplomyelia, add to the confusion by their inconsistent usage, ambiguities, and implications of their dissimilar embryogenesis. Based on the detailed radiographic and surgical findings of 39 cases of double cord malformations and the autopsy data on two other cases, this study endorses a new classification for double cord malformations and proposes a unified theory of embryogenesis for all their variant forms and features. The new classification recommends the term split cord malformation (SCM) for all double spinal cords. A Type I SCM consists of two hemicords, each contained within its own dural tube and separated by a dura-sheathed rigid osseocartilaginous median septum. A Type II SCM consists of two hemicords housed in a single dural tube separated by a nonrigid, fibrous median septum. These two essential features necessary for typing, the state of the dural tube and the nature of the median septum, do not ever overlap between the two main forms and can always be demonstrated by imaging studies so that accurate preoperative typing is always possible. All other associated structures in SCM such as paramedian nerve roots, myelomeningoceles manqué, and centromedian vascular structures frequently do overlap between types and are not reliable typing criteria. The unified theory of embryogenesis proposes that all variant types of SCMs have a common embryogenetic mechanism. Basic to this mechanism is the formation of adhesions between ecto- and endoderm, leading to an accessory neurenteric canal around which condenses an endomesenchymal tract that bisects the developing notochord and causes formation of two hemineural plates. The altered state of the emerging split neural tube and the subsequent ontogenetic fates of the constituent components of the endomesenchymal tract ultimately determine the configuration and orientation of the hemicords, the nature of the median septum, the coexistence of various vascular, lipomatous, neural, and fibrous oddities within the median cleft, the high association with open myelodysplastic and cutaneous lesions, and the seemingly unlikely relationship with fore and midgut anomalies. The multiple facets of this theory are presented in increasing complexity against the background of known embryological facts and theories; the validity of each facet is tested by comparing structures and phenomena predicted by the facet with actual radiographic, surgical, and histopathological findings of these 41 cases of SCM.

Adolescent↗
PubMed2002

Diffuse large B-cell lymphoma and its variants.

According to the World Health Organization classification of neoplastic diseases of the hematopoietic and lymphoid tissues, diffuse large B-cell lymphoma comprises about 40% of adult cases of non-Hodgkin s lymphoma. It consists of the following morphological variants: 1) centroblastic (with or without multilobulated nuclei); 2) immunoblastic (>90% of immunoblasts); 3) T cell/histiocytes rich; and 4) anaplastic. Rare morphological variants plasmablastic type, mediastinal (thymic) diffuse large B-cell lymphoma, intravascular, and primary effusion B-cell lymphoma are considered distinct variants of diffuse large B-cell lymphoma due to their unique topographic presentation and clinical behavior, as well as immunophenotypic and genetic characteristics. T-cell/histiocyte-rich B-cell lymphoma is morphologically characterized by up to 25% of large neoplastic B cells and 75-90% of reactive, non-neoplastic T cells. Mediastinal (thymic) diffuse large B-cell lymphoma is considered a subtype of diffuse large B-cell lymphoma arising in the mediastinum, with distinctive morphological, immunohistochemical, genotypic, and clinical features. Mediastinal diffuse large B-cell lymphoma is an aggressive disease with poor outcome, which probably originates from thymic B cells at the terminal stage of differentiation. During the 1997-2001 period, 720 patients were diagnosed with non-Hodgkin s lymphoma in our institution. Out of 101 (14%) patients with diffuse large B-cell lymphoma, 17 had T-cell-rich B-cell lymphoma and their median survival was less than 20 months, with no difference regarding sex, bone marrow involvement, CD30 positivity, or histiocytic component of the tumor. Twenty out of 101 patients had mediastinal B-cell lymphoma and their median survival was 21 months, with sex or degree of necrosis of the involved lymph node having no impact on survival. We studied the frequency of bcl-2 gene rearrangement in fusion with immunoglobulin receptor gene of t(14;18) and found no such event among 20 of our patients with mediastinal diffuse large B-cell lymphoma. Despite extensive efforts and constant progress in our understanding of non-Hodgkin s lymphoma pathogenesis, the diffuse large B-cell lymphoma group remains heterogeneous entity awaiting further pathological and clinical stratification.

Adult↗
PubMed2004

Pathology of upper gastrointestinal malignancies.

This review describes the most important macroscopic, histological, and molecular biological features of carcinomas of the esophagus, the gastroesophageal junction (GEJ), and the stomach. The three most frequent histological subtypes of upper GI tract carcinoma, ie, adenocarcinoma, squamous cell carcinoma, and small cell carcinoma, are considered. Important histological classifications of upper GI tract adenocarcinomas such as Lauren's classification and the World Health Organization (WHO) classification, as well as rare histological variants of esophageal and gastric cancer, are described. Routes of tumor spread and principles of tumor classification are outlined. Furthermore, descriptions of the immediate precursor lesions of upper GI tract carcinomas, ie, dysplasias, are included. Finally, somatic genetic and epigenetic changes, which are associated with tumor development in the upper GI tract, are discussed.

Adenocarcinoma↗