| Bone-marrow cells from a patient with Bloom's syndrome cultured for 48 h in the presence of BudR exhibited a striking increase in the number of sister chromatid exchanges (SCEs) in comparison to that in the marrow cells of a patient with treated polycythemia vera (PV). Thus, it appears that an increased incidence of SCE in Bloom's syndrome occurs in various differentiated types of cells, not just blood lymphocytes, and constitutes the syndrome's most characteristic cytogenetic feature. In contrast, the incidence of SCE was not increased in marrow cells and lymphocytes of the particular PV patient studied here, whose cells did exhibit increased numbers of chromatid and chromosome gaps and breaks, presumably as result of the patient's earlier treatment. An increased frequency of SCE was demonstrated in Bloom's syndrome lymphocytes using both a technique based on BudR incorporation and one based on labeling with tritated deoxycytidine. This observation constitutes evidence against the increase of SCE being due to an unusual reaction to BudR. By conventional cytogenetic techniques, chromosome instability, including chromatid and chromosome breaks, but no homologous chromatid interchanges were also recognized in Bloom's syndrome bone-marrow cells incubated in vitro (without BudR) for either 1.k or 16 h. This observation points to the existence of chromosome instability in vivo. ( info) |
| A case of thanatophoric dwarfism living for 10 weeks with minimal supportive care is presented. Although early death is usual, survival for months is compatible with the diagnosis. ( info) |
3/694. prenatal diagnosis of dyssegmental dysplasia. A case report. BACKGROUND: Since the first use of sonography, most fetal dwarfism has been detectable prenatally. The correct differentiation of the subtype of dwarfism is difficult at times. Dyssegmental dysplasia is probably an exception to these subtypes because the vertebral disorganization and occipital encephalocele at times permits prenatal diagnosis. CASE: A 34-year-old woman, gravida 3, para 1, elective abortion 1 for dwarfism, was referred at 27 weeks' gestation for cystic hygroma. Further sonographic findings included: cystic hygroma with massive ascites, micromelia, occipital encephalocele, spinal disorganization and hydramnios. The fetus and both parents appeared to have a normal karyotype. Later the pregnancy was terminated with vaginal delivery. The fetus had micromelia, camptomelia, cystic hygroma, a flat face, short neck, short trunk, narrow thorax with protuberant abdomen, scoliosis and clubfeet. CONCLUSION: Sonography is effective in prenatal diagnosis of dyssegmental dysplasia. With sonography, diagnosis of dyssegmental dysplasia becomes possible as early as the first trimester. ( info) |
4/694. Mesomelic dysplasia with periosteal thickening, radio-humeral dislocation, osteoporosis and multiple fractures. We report a boy with a new form of mesomelic dysplasia characterised by short stature, multifocal periosteal thickening, radio-humeral dislocation, osteoporosis and multiple fractures with minimal trauma. electrophoresis of fibroblast collagens detected defects in type III and type V collagen. CONCLUSION: Bone dysplasias presenting with osteopenia, abnormal trabecular pattern, bone fragility, and periosteal thickening suggest a collagenopathy. A possible collagen defect requires biochemical investigations. ( info) |
5/694. The effect of growth hormone treatment on stature in Aarskog syndrome. We describe 19 males with Aarskog syndrome who were treated with growth hormone (GH) and enrolled in the National Cooperative Growth Study (NCGS). There was a significant increase in both growth rate (3.9 /- 1.9 cm/yr vs 8.9 /- 1.7 cm/yr, p < 0.001) and height SD score (change in HtSDS = 1.0 /- 0.8). The increase in HtSDS was dependent on treatment duration, frequency of injections, weight-for-height SDS, and HtSDS at enrollment. The results of our study suggest a positive effect of GH treatment on growth and adult height in Aarskog syndrome patients. ( info) |
| Distraction osteogenesis is a method commonly used to activate bone regeneration in nonunions and osseous defects and for lengthening procedures of tubular bones. This technique involves the sectioning of a bone and the subsequent deliberate, controlled movement of the opposing sectioned edges to lengthen, widen, or reposition a bone, or all three. In this report, a patient with silver Russell syndrome and severe mandibular hypoplasia was treated by means of distraction osteogenesis of the midsymphysis to widen the mandible in concert with sagittal-ramus osteotomies to lengthen the mandible. This treatment created significantly increased arch length in the mandible, which was necessary to facilitate the patient's orthodontic treatment. We believe this is the first reported case of distraction osteogenesis to widen the mandible with the use of a tooth-borne appliance. ( info) |
| We describe a 5 years and nine months old boy who presented with facial features, vertebral anomalies and dwarfism consistent with Robinow syndrome. Investigations revealed growth hormone (GH) deficiency to be the cause of his dwarfism. We reviewed data on four other patients with Robinow syndrome from the Genentech National Cooperative Growth Study (NCGS). Results of GH testing on three out of four were available and showed GH deficiency. Recombinant human GH therapy in our patient and the three patients from the NCGS resulted in a significant increase in the growth rate per year. The cause of dwarfism in children with Robinow syndrome has hitherto not been studied. We propose its association with GH deficiency and that treatment with rhGH can result in a significant increase in the growth rate of these children. ( info) |
8/694. Severe hypertensive sequelae in a child with Seckel syndrome (bird-like dwarfism). We report a 19-year-old male with Seckel syndrome (bird-like dwarfism) who presents with malignant hypertension associated with hypertensive nephrosclerosis, dilated cardiomyopathy, and a ruptured cerebral artery aneurysm. Although end-organ injury due to chronic hypertension occurs frequently in adults, no previous reports of renal insufficiency due to hypertension exist in children or adolescents. We speculate that this patient may have been particularly prone to hypertensive end-organ injury due to his extreme short stature. ( info) |
9/694. Kyphomelic dysplasia: clinical and radiologic long-term follow-up of one case and review of the literature. The authors describe the 17-year follow-up of the (to their knowledge) only adult and only female patient affected with kyphomelic dysplasia so far described in the literature, with assessment of the phenotypic, orthopedic, and radiologic progression of this syndrome. ( info) |
10/694. A neurological disease caused by an expanded CAG trinucleotide repeat in the TATA-binding protein gene: a new polyglutamine disease? To investigate whether the expansion of CAG repeats of the TATA-binding protein (TBP) gene is involved in the pathogenesis of neurodegenerative diseases, we have screened 118 patients with various forms of neurological disease and identified a sporadic-onset patient with unique neurologic symptoms consisting of ataxia and intellectual deterioration associated with de novo expansion of the CAG repeat of the TBP gene. The mutant TBP with an expanded polyglutamine stretch (63 glutamines) was demonstrated to be expressed in lymphoblastoid cell lines at a level comparable with that of wild-type TBP. The CAG repeat of the TBP gene consists of impure CAG repeat and the de novo expansion involves partial duplication of the CAG repeat. The present study provides new insights into sporadic-onset trinucleotide repeat diseases that involve de novo CAG repeat expansion. ( info) |