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Biomedical subjects

J Spranger

Publications and source records attributed to J Spranger.

At least 37 records · Page 2Linked to original sources

Heterozygous glycine substitution in the COL11A2 gene in the original patient with the Weissenbacher-Zweymüller syndrome demonstrates its identity with heterozygous OSMED (nonocular Stickler syndrome).

The original patient with the Weissenbacher-Zweymüller syndrome was analyzed for mutations in two candidate genes expressed in cartilage (COL2A1 and COL11A2). No mutations were found in the COL2A1 gene but the COL11A2 gene contained a single-base mutation that converted a codon for an obligate glycine to a codon for glutamate at position alpha 2-955 (G955E). The results here and those published previously indicate that the Weissenbacher-Zweymüller syndrome (heterozygous OSMED), nonocular Stickler syndrome, and homozygous OSMED are all caused by mutations in the COL11A2 gene.

Abnormalities, Multiple↗

A rare form of spondylometaphyseal dysplasia-type A4.

We present 2 cases of a previously apparently unreported spondylo-metaphyseal dysplasia comprising dwarfism, severe metaphyseal changes, ovoid vertebrae and mild platyspondyly with anterior tonguing of the vertebral bodies. The inheritance may be autosomal recessive.

Child, Preschool↗

The type XI collagenopathies.

Type XI collagen is a minor component of cartilage collagen. Mutations of the three genes coding for its proteins are expressed in a peculiar phenotype. Clinical changes include facial anomalies, cleft palate and hearing defects. Ocular changes occur in some disorders. Radiographs show a spectrum of epiphyseal dysplasias with wide metaphyses and spondylar abnormalities. The pattern of clinical and radiographic changes is also found in some type II collagenopathies. On the basis of molecular studies, three type XI collagenopathies have been defined: Stickler syndrome type II, and dominant and recessive oto-spondylo-megaepiphyseal dysplasia (OSMED). Stickler syndrome I and Kniest dysplasia are type II collagenopathies with considerable clinical and radiographic overlap. Inborn errors of cartilage collagen formation lead to a family of genetically heterogeneous but pathogenetically related and hence phenotypically similar disorders. The type XI collagenopathies are part of this family.

Collagen↗

Pigmentary mosaicism in hypomelanosis of Ito. Further evidence for functional disomy of Xp.

We report on a female with mental and motor retardation, facial dysmorphism, abnormal pigmentation reminiscent to hypomelanosis of Ito (HI), and karyotypic mosaicism involving a small supernumerary marker chromosome. The marker chromosome was defined by fluorescence in situ hybridisation (FISH) as a ring X chromosome with breakpoints in the juxtacentromeric region. FISH analysis showed that the ring does not include the XIST locus at the X-inactivation centre and, therefore, may not be subject to X inactivation. X-inactivation studies with the HUMARA (human androgen receptor) and FMR1 assay showed a skewed X-inactivation pattern (85:15) with preferential inactivation of the paternal X chromosome. These results are discussed with respect to the role of functional disomy of Xp in the pathogenesis of HI.

Child, Preschool↗

Comparison of the amnestic effects of NMDA receptor antagonist MK-801 and nitric oxide synthase inhibitors: L-NAME and L-NOARG in goldfish.

Investigations indicate that the induction of long-term potentiation (LTP) may be mediated by postsynaptic N-methyl-D-aspartate (NMDA) receptors and that the maintenance of LTP may be initiated by nitric oxide (NO), a retrograde messenger carrying signals backward from the postsynaptic to the presynaptic neuron. The present study compared amnestic effects of dizocilpine maleate (MK-801), an NMDA receptor antagonist, and nitro-L-arginine-methyl-ester (L-NAME) and N-nitro-L-arginine (L-NOARG), nitric oxide (NO) inhibitors, in goldfish, using active-avoidance conditioning as the learning paradigm. The results showed that MK-801 and NO inhibitors produced anterograde amnesia at doses that did not impair performance processes necessary for learning to occur. Furthermore, MK-801 did not produce retrograde amnesia, whereas L-NAME did, suggesting that MK-801 impaired learning whereas NO inhibitors impaired memory consolidation and possibly also learning.

Amnesia↗

Increased serum levels of vascular endothelial growth factor in patients with inflammatory bowel disease.

BACKGROUND: Vascular endothelial growth factor (VEGF) is a potent angiogenic, vascular permeability-enhancing, and calcium-dependent enzyme-modulating cytokine with overexpression in various pathologic disorders, including granulomatous inflammation, tissue repair, delayed hypersensitivity reactions, rheumatoid arthritis, and tissue ischemia. The present study investigates the role of VEGF in chronic inflammatory bowel disease. METHODS: Thirty-one patients with Crohn's disease, 15 patients with ulcerative colitis, and 9 healthy volunteers were studied. VEGF serum levels were measured with a solid-phase enzyme-linked immunosorbent assay. RESULTS: Significantly increased VEGF serum levels were observed in both active Crohn's disease and active ulcerative colitis when compared with healthy controls. Patients with active Crohn's disease and active ulcerative colitis showed significantly higher VEGF serum levels than patients with quiescent disease. No difference was observed between inactive disease and healthy controls. In addition, strongly increased VEGF serum levels were found in patients with Crohn's disease with fistulas in the absence of clinical, endoscopic, histologic, and laboratory findings of disease activity. CONCLUSIONS: Significantly increased VEGF serum levels were observed in patients with active Crohn's disease and ulcerative colitis, which suggests that VEGF has an important role in chronic inflammatory bowel disease. Its possible association with fistulas has yet to be determined.

Adult↗

[Guidelines for prevention and therapy in ecological animal farms as in the example of bovine mastitis].

In ecological farming mastitis is the dominating disease in dairy cattle. The regular prophylactic use of antibiotics in farm animals is forbidden, in therapy antibiosis is restricted. A solution of this problem could be a program of systematic homeopathic prophylaxis as well as a standardised homeopathic treatment. The example of chronic catarrhal staph.-aureus-mastitis shows that there is only a certain expectancy of success by homeopathy as well as by any other medication, if the medication is combined with necessary sanitation measures. The prognosis for a homeopathic treatment is less favourable if the sanitation measures are realised incompletely. The possible negative effects of a false homeopathic medication are described.

Animal Husbandry↗

mRNA expression of ligands of the epidermal-growth-factor-receptor in the uterus.

Six different ligands of the epidermal-growth-factor receptor (EGFR) have been identified in the past. In some cervical squamous-cell carcinomas, an increased amount of proteins binding to the EGFR has been reported. In order to identify the mRNA of EGFR ligands (EGFRL), which might be overexpressed in cervical and endometrial cancers, we performed semi-quantitative reverse-transcription/polymerase chain reactions (RT-PCR) for all 6 EGFRL in RNA extracts of normal and malignant tissue samples of the human uterus. PCR products from RNA extracts of 83 patients were quantitated relative to the housekeeping gene and internal standard pyruvate dehydrogenase by analyzing the PCR kinetics of product synthesis. In extracts of normal cervix, the level of mRNA expression of the EGFRL was significantly higher than in endometrium. No significant difference was detected between normal cervix and cervical carcinomas. However, both in cervical and in endometrial cancers, mRNA expression was non-parametrically distributed and in some cervical cancers overexpression of transforming growth factor alpha (TGF-alpha), amphiregulin or EGF was observed. In endometrial cancers, mRNA levels of all EGFRL were higher than in normal endometrium. This increase was significant (p < 0.005) for TGF-alpha and amphiregulin. Thus, TGF-alpha mRNA is overexpressed in approximately 10% of cervical cancers and in the majority of endometrial cancers. Since TGF-alpha anti-sense therapy might represent a future strategy in such cancers, we also determined the absolute level of TGF-alpha mRNA expression by quantitative PCR using a cloned standard.

Cloning, Molecular↗

Kniest dysplasia: Dr. W. Kniest, his patient, the molecular defect.

Kniest dysplasia is a severe chondrodysplasia caused by the defective formation of type II collagen. We report about Dr. Kniest, who first described the condition in 1952, and his patient, who, at the age of 50 years is severely handicapped with short stature, restricted joint mobility, and blindness but is mentally alert and leads an active life. Molecular analysis of the patient's DNA showed a single base (G) deletion involving the GT dinucleotide at the start of intron 18 destroying a splice site of the COL2A1 gene. This is in accordance with molecular findings in other patients with Kniest dysplasia and confirms, in the original patient, that the disorder is caused by small inframe deletions often due to exon skipping as a result of COL2A1 splice site mutations.

Bone and Bones↗

Heterogeneity in Schwartz-Jampel chondrodystrophic myotonia.

UNLABELLED: The Schwartz-Jampel syndrome (SJS; chondrodystrophic myotonia; McK 255,800) is a recessively inherited condition defined by myotonia, short stature, and bone dysplasia. Genetic linkage between SJS and chromosomal region 1q36-34 has been observed in several families, but the gene has not yet been identified. We studied the clinical and radiological features in 81 patients from the literature and 5 own patients trying to identify distinct subgroups. In addition, we tested genetic linkage to the SJS locus on chromosome 1 in one family with two affected sibs. We found that a group of patients have mild skeletal changes which may be secondary consequences of myotonia, while another group of patients appear to have primary bone dysplasia with myotonia. Within this latter group, there are differences in age of manifestation, clinical course and pattern of bone changes. We tentatively isolate three different types of SJS: type 1A, usually recognized in childhood, with moderate bone dysplasia, corresponding to the original descriptions of Schwartz, Jampel and Aberfeld; type 1B, similar to type 1A but recognizable at birth, with more pronounced bone dysplasia resembling Kniest dysplasia; and type 2, manifest at birth, with increased mortality and bone dysplasia resembling Pyle disease. Genetic analysis of the family with two sibs affected by SJS type 2 showed evidence against linkage to chromosome 1p36-34. CONCLUSIONS: SJS is clinically and radiologically heterogeneous. The causes of heterogeneity are not known yet but are likely to include both different mutations at the SJS locus on chromosome 1 and the presence of a second SJS locus. A tentative clinico-radiological classification can be useful for the characterization of patients and the development of genotype-phenotype correlations.

Adolescent↗

Growth factor alterations in advanced diabetic retinopathy: a possible role of blood retina barrier breakdown.

Chronic hyperglycemia may cause growth factor alterations that are likely to participate in tissue remodeling typical for diabetic late complications. However, few details of such events are known. The ocular vitreous fluid allows studies of growth factor levels in human eyes (after vitrectomy). The vitreous is highly inert and protected by the blood-retina barrier and thus probably reflects growth factor production by the normal retina. Vitreous from patients with proliferative diabetic retinopathy (PDR) was compared with vitreous obtained from patients with nonproliferative eye disease and with vitreous from patients without diabetes but with marked neovascular proliferations due to ischemia. This design permits us to distinguish diabetes-related from non-diabetes-related alterations. Insulin-like growth factor I (IGF-I), IGF-II, IGF binding protein 2 (IGFBP-2), and IGFBP-3 were elevated 3- to 13-fold in nondiabetic retinal ischemia and 1.5- to 3-fold in PDR, indicating that the changes were not restricted to diabetes. These changes may partially be explained by leakage of serum into the vitreous, since IGFs and IGFBPs are 20- to 50-fold higher in serum than in vitreous, and vitreous protein content was 1.5-fold elevated in PDR subjects and 5-fold in ischemia patients compared with control subjects. TGF-beta is a proposed antiangiogenic factor in the eye. TGF-beta2 was the predominant subtype in vitreous, and its total amount was not altered in PDR patients. More importantly, the active fraction of TGF-beta was decreased by 30 and 70% in PDR and nondiabetic retinal ischemia patients, respectively. Since plasmin may control TGF-beta activation, the serum protein alpha2-antiplasmin was measured and found to be significantly elevated to 150 and 250% of control values in PDR and ischemia patients, respectively. Thus, influx of serum proteins due to microvascular disturbances and hypoxia is proposed as a possible cause for vitreous alterations of IGF-I and of active TGF-beta. These changes seem to occur late in the sequence of events leading to PDR and are not specific for diabetes, but they were also observed in other diseases characterized by retinal hypoxia.

Blood-Retinal Barrier↗

A specific collagen type II gene (COL2A1) mutation presenting as spondyloperipheral dysplasia.

We report on a patient with a skeletal dysplasia characterized by short stature, spondylo-epiphyseal involvement, and brachydactyly E-like changes. This condition has been described as spondyloperipheral dysplasia and the few published cases suggest autosomal dominant inheritance with considerable clinical variability. We found our sporadic case to be due to a collagen type II defect resulting from a specific COL2A1 mutation. This mutation is the first to be located at the C-terminal outside the helical domain of COL2A1. A frameshift as consequence of a 5 bp duplication in exon 51 leads to a stop codon. The resulting truncated C-propeptide region seems to affect helix formation and produces changes of chondrocyte morphology, collagen type II fibril structure and cartilage matrix composition. Our case with its distinct phenotype adds another chondrodysplasia to the clinical spectrum of type II collagenopathies.

Amino Acid Sequence↗

Clinical and ultrastructural findings in three patients with geleophysic dysplasia.

Geleophysics dysplasia, a rare disorder with autosomal-recessive inheritance, is characterized by short stature with a "happy-looking" facial appearance. Nonskeletal findings, particularly in an advanced stage, include hepatosplenomegaly and valvular cardiopathy. Based on the clinical picture and the detection of lysosome-like inclusions in hepatocytes, the underlying cause of the condition is considered to be a storage defect in the metabolism of glycoproteins. The clinical course, with progressive worsening of the condition favors this hypothesis. We report on 3 further cases, in which light and electron microscopic studies of iliac crest biopsies and cultured skin fibroblasts provided additional evidence that geleophysic dysplasia represents a lysosomal storage disease. The additional discovery of storage vacuoles in chondrocytes and skin fibroblasts strongly suggests that the condition is a generalized storage defect. To date, it has not yet been possible to identify the presumed biochemical defect in the metabolic pathways of glycoproteins.

Bone and Bones↗

An unknown spondylo-meta-epiphyseal dysplasia in sibs with extreme short stature.

In three sibs of Jordanian descent a unique type of severe spondylo-meta-epiphyseal dysplasia results in extreme disproportionate dwarfism. They have a distinct facial appearance with hypotelorism, prognathia, and hypodontia. The limbs are short and the hands and feet stubby. Radiologically, the irregular end plates of the vertebral bodies, the very small and late appearing epiphyseal ossification centres, and the hypoplastic acetabular roofs are most impressive. Histopathologic studies of the growth plate demonstrate characteristic findings with fingerprint-like inclusion bodies in the hypertrophic chondrocytes. This seems to be a distinct, autosomal recessive skeletal dysplasia.

Adolescent↗

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↗

[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↗