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Notes: The progression of cellular repopulation and collagen synthesis in fresh-frozen rat patellar tendon allografts was investigated by means of indirect immunofluorescence histologic analysis and electron microscopic techniques for 8 weeks after transplantation. In each of 10 procedures, the medial half of the patellar tendon with a tibial bone block was harvested from a Wistar rat and transplanted into a corresponding defect in the medial patellar tendon of a Lewis rat. Actin filaments in the repopulating cells and newly synthesized collagen fibrils in the graft were identified with rhodamine-phalloidin stain and with a polyclonal antibody against type III collagen aminopro-peptide. On the first day after transplantation, no specific fluorescence was detected in the graft. One week later, specific labeling for fibrillar-actin (F-actin) and type III collagen aminopropeptide was detected in an area extending from the adjacent granulation tissue into the proximal end of the graft. F-actin and type III collagen aminopropeptide were aligned along the longitudinal axis of the graft and extended from the proximal suture site toward the distal portion. Two weeks after transplantation, fibrillar labeling for F-actin and type III collagen amino-propeptide showed that remodeling had extended to the midportion of the graft. Labeling throughout the entire graft was detected 4 weeks after transplantation. During the entire remodeling process, the repopulated fibroblasts consistently retained their elongated shape and their alignment with the longitudinal axis of the graft. The cells developed well-organized actin bundles at their peripheries, which identified them as having a myofibroblast phenotype. Immunofluorescence detection for type III collagen aminopropeptide also showed consistent alignment parallel to the longitudinal axis of the graft and a fibrillar arrangement. Electron microscopy revealed thinner collagen fibrils in the vicinity of the fibroblasts, which were aligned in the direction of the actin bundles. These results indicate that, during the early remodeling phase, collagen synthesis and deposition in the graft proceeds while the original alignment of the graft matrix is preserved. The close association between the alignment of actin bundles in repopulated “myofibroblastic” cells and that of newly synthesized collagen fibrils along the lines of the graft matrix may represent evidence of force transmission between the actin cytoskeleton and the linking extracellular matrix in vivo.

Notes: [Auszug] Closure of the ductus arteriosus requires prenatal formation of intimal cushions, which occlude the vessel lumen at birth. Survival of newborns with severe congenital heart defects, however, depends on ductal patency. We used a gene transfer approach to create a patent ductus arteriosus by ...

Notes: Abstract Genetic deficiency of the glycogen-debranching enzyme (debrancher) causes glycogen storage disease type III (GSD III), which is divided into two subtypes: IIIa and IIIb. In GSD IIIb, glycogen accumulates only in the liver, whereas both liver and muscles are involved in GSD IIIa. The molecular basis for the differences between the two subtypes has not been fully elucidated. Recently, mutations in exon 3 of the debrancher gene were reported to be specifically associated with GSD IIIb. However, we describe a homozygous GSD IIIb patient without mutations in exon 3. Analysis of the patient’s debrancher cDNA revealed an 11-bp insertion in the normal sequence. An A to G transition at position –12 upstream of the 3′ splice site of intron 32 (IVS 32 A–12→G) was identified in the patient’s debrancher gene. No mutations were found in exon 3. Mutational analysis of the family showed the patient to be homozygous for this novel mutation as well as three polymorphic markers. Furthermore, the mother was heterozygous and the parents were first cousins. The acceptor splice site mutation created a new 3′ splice site and resulted in insertion of an 11-bp intron sequence between exon 32 and exon 33 in the patient’s debrancher mRNA. The predicted mutant enzyme was truncated by 112 amino acids as a result of premature termination. These findings suggested that a novel IVS 32 A–12→G mutation caused GSD IIIb in this patient.

Notes: Summary Uptake of radioactivity from 14C-galactose into gangliosides by cultured skin fibroblasts was studied. GM3 was the major ganglioside in control human fibroblasts. An increase of GM1 was demonstrated in GM1-gangliosidosis fibroblasts. The degree of GM1 accumulation was correlated with the clinical types of this disease. The fibroblasts from an infantile-type patient showed a marked increase of GM1. In late-onset types the amount of total gangliosides was only slightly increased, but the distribution of individual gangliosides was definitely abnormal; a relative increase of GM1 was demonstrated in these cases. GM1 β-galactosidase activities were not detectable in either infantile or late-onset cases.

Notes: Summary Six juvenile and adult patients with progressive neurological diseases and β-galactosidase deficiency were reported. Any diseases known to date were denied. These cases together with ten case reports in the literature were reviewed and were classified into three groups from clinical and biochemical points. Group 1 patients were characterized by progressive ataxia and myoclonus with gargoyle changes and macular cherry-red spots. In this syndrome β-galactosidase activity seems to be secondarily affected by other biochemical defects. A group 2 patient showed similar neurological manifestations without gargoyle changes or macular cherry-red spots. Patients with these clinical features not associated with β-galactosidase deficiency have also been described in the literature. Group 3 patients had progressive pyramidal and extrapyramidal disease without gargoyle changes or macular cherry-red spots. These cases may represent juvenile and adult type GM1-gangliosidosis. Accumulation of GM1 has not yet been demonstrated.