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J Spranger

Publications and source records attributed to J Spranger.

At least 55 records · Page 3Linked to original sources
PubMed1996

The deletion of six amino acids at the C-terminus of the alpha 1 (II) chain causes overmodification of type II and type XI collagen: further evidence for the association between small deletions in COL2A1 and Kniest dysplasia.

We have identified an 18 bp deletion in exon 49 of the type II procollagen gene (COL2A1) in a patient with Kniest dysplasia. The deletion is located at the very C-terminus of the helical domain and removes two of three Gly-Pro-Pro triplets at positions 1007-1012, which are thought to be involved in helix formation and stability. Morphological investigation of an iliac crest biopsy showed large inclusions in the endoplasmic reticulum of chondrocytes, reflecting impaired secretion of type II collagen. Electrophoretic analysis of collagens extracted from cartilage or synthesised by cultured chondrocytes showed that type II and also type XI procollagen molecules containing mutant alpha 1 (II) chains showed post-translational overmodification. These observations provide further evidence for the general association of Kniest dysplasia with small deletions in the helical domain of type II collagen.

Amino Acid Sequence↗
PubMed1995

[TNF-alpha level in the vitreous body. Increase in neovascular eye diseases and proliferative diabetic retinopathy].

BACKGROUND: Deficient retinal capillary perfusion results in angioneogenesis of the eye. Its extension depends on the degree of ischemia. Mild stages are restricted to the retina, while marked ischemia results in neovascularization of the iris (rubeosis iridis). The neovascularization may be induced by the release of growth factors into the vitreous. Tumor necrosis factor alpha seems to be an important angiogenetic growth factor. PATIENTS AND METHODS: The patients were divided up into three groups with different retinal stages of ischemia, as judged by the extension of new vessel formation of the eye: a control group without angioneogenesis, a diabetes group with less severe to moderate angioneogenesis of patients with proliferative diabetic retinopathy and a rubeosis group with massive angiogenesis (rubeosis iridis) resulting from different causes. TNF-alpha was determined by immunological methods. RESULTS: The TNF-alpha level of vitreous in rubeosis (25.8 pg/ml; n = 6) was 2-fold elevated compared to controls (13.1 pg/ml; n = 10; p < 0.05) and 1.4-fold elevated compared to the diabetes group (18.2 pg/ml; n = 17). The values ranged from unmeasurable values to 41.25 pg/ml. Within the rubeosis group similar changes were observed independently of the causes of ischemia. There was no correlation between TNF-alpha-levels in the diabetes group and serum creatinine. CONCLUSIONS: 1. TNF-alpha is upregulated in ischemia. 2. TNF-alpha seems to be a mediator of angiogenesis in the eye. 3. Changes in diabetes may be secondary to local ischemia rather than being specific for diabetic retinopathy.

Adult↗
PubMed1994

Microcephalic osteodysplastic dysplasia.

We present two patients with a distinct facial phenotype, short stature, brachydactyly, clubfoot deformities, cataracts, microcephaly, and normal intelligence. Similar radiographic abnormalities of the spine, long bones, hands, and feet were noted. These patients are similar to 2 males previously described by Saul and Wilson [1990: Am J Med Genet 35:388-393]. These 4 patients appear to have a unique skeletal dysplasia characterized by microcephaly, distinct facial phenotype, multisystem abnormalities, and short stature of postnatal onset.

Abnormalities, Multiple↗
PubMed1994

Autosomal dominant spondylarthropathy due to a type II procollagen gene (COL2A1) point mutation.

Osteoarthrosis represents a very common disease with heterogeneous etiology. In some pedigrees linkage of the condition with the type II collagen gene (COL2A1) has been established, but information on the underlying gene defect is still incomplete as only one mutation causing this phenotype has been identified. We analyzed the COL2A1 gene in a 27-year-old woman and her 47-year-old mother presenting with severe premature osteoarthrosis and X-ray signs compatible with mild spondyloepiphyseal dysplasia. Examination of the complete gene in both patients was done by amplification of all 54 exons, screening of the PCR products by SSCP-analysis, and subsequent sequencing. In mother and daughter a G to A transition at the 5'-end of exon 21 was detected, leading to a substitution of serine for glycine at position 274 of the triple helical domain. The mutation was not present in unaffected family members or in healthy control individuals. The autosomal dominant spondylarthropathies may represent the less severe entities of the clinical spectrum of type II collagenopathies.

Adult↗
PubMed1994

The type II collagenopathies: a spectrum of chondrodysplasias.

With the application of molecular techniques the aetiopathogenesis of skeletal dysplasias is gradually elucidated. Recent advances show that some bone dysplasias result from defects in the biosynthesis of type II (cartilage) collagen. Clinical entities caused by mutations in the COL2A1 gene coding for type II collagen comprise achondrogenesis II, hypochondrogenesis, spondyloepiphyseal dysplasia congenita, Kniest dysplasia, Stickler arthroophthalmopathy and mild dominant spondyloarthropathy. The mutations are expressed in the heterozygous state, and inheritance of type II collagenopathies is autosomal dominant. The wide range of clinical manifestations is not well understood but characterization of the basic defect may provide clues to establish specific genotype-phenotype correlations.

Collagen Diseases↗
PubMed1994

Kniest dysplasia is caused by dominant collagen II (COL2A1) mutations: parental somatic mosaicism manifesting as Stickler phenotype and mild spondyloepiphyseal dysplasia.

We describe two unrelated children with Kniest dysplasia, a severe autosomal dominant form of chondrodysplastic dwarfism associated with cleft palate, progressive arthropathy, myopia and retinal detachment. In the first patient the disorder was caused by a 28 base pair exon 12/intron 12 deletion in the gene coding for type II collagen. Her mother had mild abnormalities of the vertebral bodies and long bones compatible with abnormalities seen in Stickler arthro-ophthalmopathy. The second child had a transition of AG to GG at the 3' splice site of intron 20 of the COL2A1 gene. Her father had premature polvarthrosis interpreted as a sequela of mild spondyloepiphyseal dysplasia. Molecular studies revealed that the mother of the first and the father of the second child each had somatic mosaicism of the same mutation as their children. Heterozygous mutations of the gene coding for type II collagen can cause Kniest dysplasia, and somatic mosaicism for the same mutations can result in the Stickler phenotype or in mild spondyloepiphyseal dysplasia leading to premature polyarthrosis.

Adult↗
PubMed1993

Cerebral malformation, seizures, hypertrichosis, distinct face, claw hands, and overlapping fingers in sibs of both sexes.

We report on sibs of both sexes with a multiple malformation syndrome of cerebral malformation, seizures, hypertrichosis, distinct face, claw hands, and overlapping fingers. The older boy died in a tonic extension spasm at age 4 months. When discharged, the younger girl was 3.5 months old. This appears to be an autosomal recessive syndrome which to our knowledge has not been described before.

Abnormalities, Multiple↗
PubMed1993

Cognitive skills in achondroplasia.

Increased intracranial pressure and ventricular and subarachnoidal dilatation are common manifestations in achondroplasia. They rarely lead to major neurologic and/or psychomotor deficits and neurosurgical intervention is seldom needed. The present study was undertaken to detect signs of minor cerebral dysfunction and discuss possibilities of their prevention. Thirty children with achondroplasia were compared to 3 control groups: their next-born sibs, 30 children with other forms of dwarfism, and 30 children with normal height. Early development was assessed by means of questionnaires. Cognitive skills were evaluated with the German version of the Cognitive Abilities Test and the Lorge-Thorndike Intelligence Test. Personality data were tested using standardized neuroticism, extraversion, and anxiety scales. Children with achondroplasia had more frequent histories of delayed motor development, retarded speech development, and lower school grades in language-related specialties. Psychometric testing disclosed total and subtest scores in the population-based normal range. In comparison with their sibs and matched controls children with achondroplasia had significantly lower total scores mainly caused by low scores in the subtest "verbal comprehension." We conclude that verbal comprehension is significantly impaired in children with achondroplasia. This partial deficiency is probably related to frequent middle ear infections and resulting conductive hearing loss. Hypotonia with delayed oropharyngeal muscle coordination and parental response to an altered, more infantile instinctive releasing pattern may be contributing factors.

Achondroplasia↗
PubMed1993

Osteogenesis imperfecta and hyperplastic callus formation: light- and electron-microscopic findings.

In rare cases of osteogenesis imperfecta, an "overshoot" growth of new bone may occur, which, clinically gives the impression of a tumour. This condition is known as hyperplastic callus formation. Morphology showed an excessive mixed desmal-chondral osteoneogenesis. Atypical collagen fibrils in non-callus tissue represent an indicator for this callus formation in individual patients.

Bony Callus↗
PubMed1993

Kniest and Stickler dysplasia phenotypes caused by collagen type II gene (COL2A1) defect.

Kniest and Stickler dysplasia are two chondrodysplasias characterized by specific phenotypes. No basic defect has been found in patients with Kniest dysplasia, whereas Stickler dysplasia is one of four chondrodysplasias for which mutations of type II procollagen gene (COL2A1) have been identified. We studied a 2-year-old girl presenting with manifestations of Kniest dysplasia and her mother showing a Stickler phenotype. Analysing COL2A1 in both patients, we detected the same 28 basepair deletion spanning the 3'-exon/intron boundary of exon 12 in mother and daughter. We were able to prove a somatic mosaic status for this mutation in the mother which accounts for her milder Stickler-like phenotype.

Adult↗
PubMed1993

[Osteogenesis imperfecta in childhood and adolescence].

BACKGROUND: 209 patients with osteogenesis imperfecta type I, III and IV were studied to provide data on the natural course of the disease until the end of the second decade. RESULTS: Weight and length at birth were normal in most cases of type I and IV, markedly reduced in type III. Fractures and deformities at birth were most frequent in type III. High fracture rates occurred in type III and IV up to 8-10 years of age. Skeletal deformities developed primarily in the lower extremities and the spine, again most frequently in type III. Radiological features were--besides osteopenia--Wormian bones of the skull, pseudoarthroses, deformity of the pelvis, popcorn epiphyses (most frequent in type III) and hyperplastic callus (most frequent in type IV). Longitudinal growth of patients with type I was in the lower normal range, while patients with type III and IV developed marked growth deficiency. Motor performance was not severely impaired in most cases of type I; however, all type III patients and 71% of type IV patients were confined to a wheelchair in later life. CONCLUSION: As defined, type I patients had a mild clinical course until early adulthood. Type III and IV represented a spectrum of severely affected patients. Although type IV patients were less affected at birth, their postnatal course in some respects resembled that of type III.

Activities of Daily Living↗
PubMed1992

Osteogenesis imperfecta: a clinical study of the first ten years of life.

One hundred twenty-seven children with osteogenesis imperfecta (O.I.) were studied during the first 10 years of life. According to Sillence, 40 patients were assigned to type I, 39 to type III, and 48 to type IV O.I. Centiles for height, weight, and the annual number of fractures could be established for the different types of O.I. The development of the skeletal changes could be documented for the different forms of the disease. At birth, the skeletal changes were significantly more severe in type III than in type IV patients. During the first 10 years of life the number of fractures, extent of skeletal deformities, and growth retardation did not differ between types III and IV. Only fracture nonunion, dentinogenesis imperfecta, and congenital cardiac malformations were more frequent in type III than in type IV. Papillary calcifications of the kidney and kidney stones were diagnosed in 4 type III and 2 type IV patients. Hemihypertrophy of the body developed in 2 type I patients. Although types III and IV patients suffered from severe short stature, serum insulin-like growth factor (IGF) I was in the normal range.

Body Height↗