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Jacqueline T Hecht - One of the best experts on this subject based on the ideXlab platform.

  • Hereditary Multiple Exostosis and pain
    Journal of Pediatric Orthopaedics, 2005
    Co-Authors: Sandra Darilek, Catherine A Wicklund, Diane M Novy, Allison Scott, Michael J Gambello, Dennis A Johnston, Jacqueline T Hecht
    Abstract:

    This study was undertaken to characterize pain in individuals with Hereditary Multiple Exostosis (HME). Two hundred ninety-three patients with HME completed a questionnaire designed to assess pain as well as its impact on their life. Eighty-four percent of participants reported having pain, indicating that pain is a real problem in HME. Of those with pain, 55.1% had generalized pain. Two factors were found to be associated with pain outcome: HME-related complications and surgery. Individuals who had HME-related complications were five times more likely to have pain, while those who had surgery were 3.8 more likely to have pain. No differences were found between males and females with respect to pain, surgery, or HME-related complications. The results of this study indicate that the number of individuals with HME who have pain has been underestimated and that pain is a problem that must be addressed when caring for individuals with HME.

  • reevaluation of a genetic model for the development of Exostosis in Hereditary Multiple Exostosis
    American Journal of Medical Genetics, 2002
    Co-Authors: Catherine Rhoades Hall, Jacqueline T Hecht, William G Cole, Richard Haynes
    Abstract:

    EXT1 and EXT2 are genes that have been shown to cause Hereditary Multiple Exostosis (HME), a syndrome marked by the formation of bony growths juxtaposed to the growth plate. These genes are members of a growing family of proteins with glycosyltransferase activity required for the synthesis of heparan sulfate chains. This protein activity is predicted to play a role in the expression of proteoglycans on the cell surface and in the extracellular matrix. We and others have previously suggested that a two-hit mutational model applies to the development of an Exostosis where a germline mutation coupled with a somatic mutation results in the loss of EXT1 or EXT2 function and subsequent tumor formation. We report the direct sequencing and loss of heterozygosity (LOH) analysis of 12 exostoses from 10 HME families, 4 solitary exostoses, and their corresponding constitutional DNA. Of the 16 exostoses screened, we find only one solitary case in which two somatic mutations, a deletion and an LOH, are present. This provides limited support for the two-hit hypothesis involving the EXT1 and EXT2 genes for the development of an Exostosis. Alternative models are developed based on the functional significance of EXT proteins in heparan sulfate biosynthesis. © 2002 Wiley-Liss, Inc.

  • Hereditary Multiple Exostosis and chondrosarcoma linkage to chromosome ii and loss of heterozygosity for ext linked markers on chromosomes ii and 8
    American Journal of Human Genetics, 1995
    Co-Authors: Jacqueline T Hecht, Susan H Blanton, Deborah Hogue, Louise C Strong, Marc F Hansen, Michael J Wagner
    Abstract:

    Hereditary Multiple Exostosis (EXT) is an autosomal dominant disorder characterized by bony exostoses at the ends of the long bones. Linkage studies have recently suggested that there are three chromosomal locations for EXT genes, 8q24.1 (EXT1), the pericentric region of 11 (EXT2), and 19p (EXT3). As part of a larger study to determine the frequencies of the three EXT types in the United States, we have ascertained a large multigenerational family with EXT and one family member with a chondrosarcoma. This family demonstrated linkage of the disease to chromosome 11 markers. The constitutional and tumor DNAs from the affected family member were compared using shortandem-repeat markers from chromosomes 8, 11, and 19. Loss of heterozygosity (LOH) in the tumor was observed from chromosome 8 and 11 markers, but chromosome 19 markers were intact. An apparent deletion of the marker D11S903 was observed in constitutional DNA from all affected individuals and in the tumor sample. These results indicate that the EXT2 gene maps to the region containing marker D11S903, which is flanked by markers D11S1355 and D11S1361. Additional constitutional and chondrosarcoma DNA pairs from six unrelated individuals, two of who had EXT, were similarly analyzed. One tumor from an individual withmore » EXT demonstrated LOH for chromosome 8 markers, and a person with a sporadic chondrosarcoma was found to have tumor-specific LOH and a homozygous deletion of chromosome 11 markers. These findings suggest that EXT genes may be tumor-suppressor genes and that the initiation of tumor development may follow a multistep model. 23 refs., 3 figs., 2 tabs.« less

  • linkage study of Hereditary Multiple Exostosis
    American Journal of Human Genetics, 1994
    Co-Authors: Susan H Blanton, Deborah Hogue, Jacqueline T Hecht
    Abstract:

    Hereditary Multiple Exostosis (EXT) is an autosomal dominant disorder characterized by the formation of cartilage capped prominences that develop from the epiphyses of the long bones. Orthopedic complications involve limb length inequalities, bowing, bony synostoses, impaired articular function and short stature. Chondrosarcoma develops in less that 5% of EXT individuals. EXT is genetically heterogeneous with three different chromosomal locations currently identified on chromosome 8, 11 and 19. We have recently identified and studied 10 large multigenerational EXT families, two of which have an affected individual with a chrondrosarcoma. Linkage analysis, using D8S200, D8S85, D8S199 and D8S198, shows that 6 of these families map to 8q24 including the two in which a chondrosarcoma has developed in a member of the family. Loss of heterozygosity studies between the tumor tissue and constitutional DNAs are underway. Two families have recombinations between D8S85 and D8S199 and additional intervening markers are being tested to further narrow this region which is postulated to include the gene locus. The four families excluded from chromosome 8 are being tested for linkage to short tandem repeat markers on chromosomes 11 and 19.

Scott Selleck - One of the best experts on this subject based on the ideXlab platform.

  • Functional conservation of the human EXT1 tumor suppressor gene and its Drosophila homolog tout velu
    Development Genes and Evolution, 2007
    Co-Authors: Ujjaini Dasgupta, Bharat L. Dixit, Melissa Rusch, Scott Selleck
    Abstract:

    Heparan sulfate proteoglycans play a vital role in signaling of various growth factors in both Drosophila and vertebrates. In Drosophila , mutations in the tout velu ( ttv ) gene, a homolog of the mammalian EXT1 tumor suppressor gene, leads to abrogation of glycosaminoglycan (GAG) biosynthesis. This impairs distribution and signaling activities of various morphogens such as Hedgehog (Hh), Wingless (Wg), and Decapentaplegic (Dpp). Mutations in members of the exostosin ( EXT ) gene family lead to Hereditary Multiple Exostosis in humans leading to bone outgrowths and tumors. In this study, we provide genetic and biochemical evidence that the human EXT1 ( hEXT1 ) gene is conserved through species and can functionally complement the ttv mutation in Drosophila . The hEXT1 gene was able to rescue a ttv null mutant to adulthood and restore GAG biosynthesis.

  • functional conservation of the human ext1 tumor suppressor gene and its drosophila homolog tout velu
    Development Genes and Evolution, 2007
    Co-Authors: Ujjaini Dasgupta, Bharat L. Dixit, Melissa Rusch, Scott Selleck
    Abstract:

    Heparan sulfate proteoglycans play a vital role in signaling of various growth factors in both Drosophila and vertebrates. In Drosophila, mutations in the tout velu (ttv) gene, a homolog of the mammalian EXT1 tumor suppressor gene, leads to abrogation of glycosaminoglycan (GAG) biosynthesis. This impairs distribution and signaling activ- ities of various morphogens such as Hedgehog (Hh), Wingless (Wg), and Decapentaplegic (Dpp). Mutations in members of the exostosin (EXT) gene family lead to Hereditary Multiple Exostosis in humans leading to bone outgrowths and tumors. In this study, we provide genetic and biochemical evidence that the human EXT1 (hEXT1) gene is conserved through species and can functionally complement the ttv mutation in Drosophila. The hEXT1 gene was able to rescue a ttv null mutant to adulthood and restore GAG biosynthesis.

Tomohiko Hirose - One of the best experts on this subject based on the ideXlab platform.

  • low energy dislocation of the hip joint in an adult with Hereditary Multiple Exostosis
    European Journal of Orthopaedic Surgery and Traumatology, 2008
    Co-Authors: Tomohiko Hirose
    Abstract:

    This article will describe the incidence of a low-energy hip dislocation, due to a fall from a standing height, in a 64-year-old female with Hereditary Multiple Exostosis (HME). The dislocated left hip was reduced under spinal anesthesia, and the patient was restricted to 3 weeks of bed rest with skeletal traction of the affected limb. The post-reduction CT scan revealed a tangential fracture in the apex of the Exostosis on the posteroinferior aspect of the femoral neck. The Exostosis was assumed to impinge on the ischium and that the lever mechanism led to the dislocation. The 3 month follow-up MRI revealed no evidence of subluxation or avascular necrosis of the femoral head.

  • Low energy dislocation of the hip joint in an adult with Hereditary Multiple Exostosis
    European Journal of Orthopaedic Surgery & Traumatology, 2008
    Co-Authors: Tomohiko Hirose
    Abstract:

    This article will describe the incidence of a low-energy hip dislocation, due to a fall from a standing height, in a 64-year-old female with Hereditary Multiple Exostosis (HME). The dislocated left hip was reduced under spinal anesthesia, and the patient was restricted to 3 weeks of bed rest with skeletal traction of the affected limb. The post-reduction CT scan revealed a tangential fracture in the apex of the Exostosis on the posteroinferior aspect of the femoral neck. The Exostosis was assumed to impinge on the ischium and that the lever mechanism led to the dislocation. The 3 month follow-up MRI revealed no evidence of subluxation or avascular necrosis of the femoral head. L’article décrit l’incidence d’une luxation de la hanche survenue par traumatisme à basse énergie après chute de sa hauteur d’une patiente âgée de 64 ans et porteuse d’une maladie exostosante héréditaire. La hanche gauche luxée fut réduite sous anesthésie générale et la patiente resta alitée pendant trois semaines avec le membre inférieur gauche en traction. Le scanner fait après réduction mit en évidence une fracture tangentielle au sommet d’une exostose postéro-inférieure du col du fémur. L’exostose était en conflit avec l’ischion et la luxation s’était produite par effet de levier. Le contrôle IRm à trois mois ne mit en évidence aucun signe de subluxation ou de nécrose avasculaire de la tête fémorale.

Ujjaini Dasgupta - One of the best experts on this subject based on the ideXlab platform.

  • Functional conservation of the human EXT1 tumor suppressor gene and its Drosophila homolog tout velu
    Development Genes and Evolution, 2007
    Co-Authors: Ujjaini Dasgupta, Bharat L. Dixit, Melissa Rusch, Scott Selleck
    Abstract:

    Heparan sulfate proteoglycans play a vital role in signaling of various growth factors in both Drosophila and vertebrates. In Drosophila , mutations in the tout velu ( ttv ) gene, a homolog of the mammalian EXT1 tumor suppressor gene, leads to abrogation of glycosaminoglycan (GAG) biosynthesis. This impairs distribution and signaling activities of various morphogens such as Hedgehog (Hh), Wingless (Wg), and Decapentaplegic (Dpp). Mutations in members of the exostosin ( EXT ) gene family lead to Hereditary Multiple Exostosis in humans leading to bone outgrowths and tumors. In this study, we provide genetic and biochemical evidence that the human EXT1 ( hEXT1 ) gene is conserved through species and can functionally complement the ttv mutation in Drosophila . The hEXT1 gene was able to rescue a ttv null mutant to adulthood and restore GAG biosynthesis.

  • functional conservation of the human ext1 tumor suppressor gene and its drosophila homolog tout velu
    Development Genes and Evolution, 2007
    Co-Authors: Ujjaini Dasgupta, Bharat L. Dixit, Melissa Rusch, Scott Selleck
    Abstract:

    Heparan sulfate proteoglycans play a vital role in signaling of various growth factors in both Drosophila and vertebrates. In Drosophila, mutations in the tout velu (ttv) gene, a homolog of the mammalian EXT1 tumor suppressor gene, leads to abrogation of glycosaminoglycan (GAG) biosynthesis. This impairs distribution and signaling activ- ities of various morphogens such as Hedgehog (Hh), Wingless (Wg), and Decapentaplegic (Dpp). Mutations in members of the exostosin (EXT) gene family lead to Hereditary Multiple Exostosis in humans leading to bone outgrowths and tumors. In this study, we provide genetic and biochemical evidence that the human EXT1 (hEXT1) gene is conserved through species and can functionally complement the ttv mutation in Drosophila. The hEXT1 gene was able to rescue a ttv null mutant to adulthood and restore GAG biosynthesis.

Natsuo Yasui - One of the best experts on this subject based on the ideXlab platform.

  • An Osteochondroma Limiting Flexion of the Proximal Interphalangeal Joint in Hereditary Multiple Exostosis: a Case Report
    HAND, 2010
    Co-Authors: Shinji Yoshioka, Yoshitaka Hamada, Shinjiro Takata, Hiroaki Takai, Natsuo Yasui
    Abstract:

    We describe a patient in which an osteochondroma, which resulted from Hereditary Multiple exostoses, limited flexion of the proximal interphalangeal (PIP) joint at birth. The tumor grew over the original distal head of the proximal phalanx, and the early appearance of a second ossification center on the base of the middle phalanx was observed. The mass was removed surgically when the patient was 17 months old. There was an improvement in the range of motion at a follow-up evaluation 3 years later. The tumor shape and the growth of the affected PIP joint are examined in detail.