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Biomedical subjects

A Schulz

Publications and source records attributed to A Schulz.

At least 235 records · Page 13Linked to original sources
PubMed1977

A reliable method of preparing undecalcified human bone biopsies for electron microscopic investigation.

Undecalcified preparation of bone tissue for electron microscopic investigation depends on an adequate embedding method. A low viscosity resin proved to comply with the particular conditions as there is good infiltration of specimen by the monomer medium and also sufficient hardness of the polymerization product. Both properties stabilize the transition of soft tissue to mineralized bone surface; thus reproducible results of good quality are obtained in ultra-thin sectioning. A special preparation technique of human bone biopsies for simultaneous light and electron microscopic investigation has been developed. The method is based on experiences with approximately 300 iliac crest biopsies in metabolic and endocrine bone disorders.

Biopsy↗
PubMed1977

[Histomorphometric studies on the influence of long-term calcitonin therapy on osteodystrophia deformans Paget].

Bone alterations in Paget's disease, have been studied by histomorphometrical evaluation iliac creat bone biopsies before and after long-term treatment with human ans salmon calcitonin. Therapeutic effect was controlled from 12, up to 48 months. All-together 28 bone biopsies were taken from 9 patients (aged 46 to 71 years) with Paget's disease of their os ileum. The biopsies were prepared for histological examination without previous decalcification, cut, stained and quantitatively analysed at the light microscopic level. By means of a point counting method we determined the parameters of bone structure, bone formation and bone resorption. Before therapy was started, trabecular bone alterations could be observed which were typical for Paget's disease of bone as there were bulky trabeculare, increased remodelling surfaces and giant osteoclasts. Following treatment with calcitonin a dramatic reduction of bone remodelling surfaces and a normalization of bone structure occurs. Considering our previous electon microscopy findings, a reduction of the number of osteoclasts as well as their nuclear content, might be explained by an inhibitory effect of calcitonin on cell fusion of osteoclastic precursor cells. In 2 cases, an interruption or hormonal treatment of 5 to 12 months, presented no risk of losing the therapeutic effect.

Aged↗
PubMed1976

[Central giant cell granuloma. Histochemical and ultrastructural study on giant cell function (author's transl)].

Multinucleated giant cells in giant cell granuloma are formed by cell fusion of capillary pericytes. In our present study we tried to analyze cell function and activity by histologic, histochemical, and electronmicroscopic examination of giant cells. Lysosomal enzymes such as acid phosphatase and amino-peptidase were found in giant cells which is in agreement with former work. By their lysosomal system giant cells are proved phagocytic. In addition, giant cells being localized at trabecular surfaces of newly formed woven bone may develop osteoclastic functions. The enzymatic and funcational resemblance of giant cells and multinucleated osteoclasts points to the possibility of a similar cytogenesis of both cell types.

Bone Resorption↗
PubMed1976

[Immunoreactive parathyroid hormone, 25-hydroxycalciferol and bone histology in renal osteodystrophy (author's transl)].

Immunoreactive parathyroid hormone (iPTH) and 25-hydroxycalciferol (25(OH)D) serum levels were determined in 32 patients with renal osteopathy, they were correlated with the results of bone biopsy and other clinical parameters. iPTH was closely related to bone histology, it did not correspond to serum calcium and alkaline phosphatase, but the correlation to serum phosphate was statistically significant. 25(OH)D levels were not related to the histological findings of osteomalacia or increased bone resorption, while a correlation between the vitamin D metabolite and serum calcium could be observed. Since iPTH and 25(OH)D levels exhibited a significant correlation, an inhibitory effect of 25(OH)D on parathyroid gland function in renal failure was discussed.

Alkaline Phosphatase↗
PubMed1976

[Central giant cell granuloma: histochemical and ultrastructural study on its histogenesis (author's transl)].

Until now numerous studies on central giant cell granuloma of jawbones have not been able to reveal the histogenesis of this tumourlike lesion. The aim of the present investigation in two surgically proven cases was to study this question by means of histochemical and electron-microscopic methods. Rather similar histochemical properties were shown in giant cells and pericytes of capillary sproute penetrating the granuloma. Cell fusion occurred between both cell types as was observed by electron microscopy. The process of cell fusion is defined by characteristic interdigitations of cell membranes. Therefore pericytes are believed to be the stem cells of multinucleated giant cells in giant cell granuloma. The abundance of giant cells usually occurring in the granuloma might be explained by plenty of capillary sprouts made up by clusters of pericytes. The factors inducing the pericytic cell fusion process are still unknown. The question arises whether cytogenesis of giant cells in giant cell granuloma might be similar in other giant cell lesions or even in the development of multinucleated osteoclasts.

Adult↗
PubMed1976

[The effect of long-term calcitonin administration on bone cells and bone mineralization in the rat (author's transl)].

The effect of calcitonin on bone tissue was studied in rat cortical and trabecular bone after long-term treatment. The aim of this study was to get exact data on calcitonin action on bone tissue by histomorphometry. Histomorphometric analysis of bone alterations was performed using undecalcified longitudinal as well as grounded cross sections of the tibial metaphysis and diaphysis. In agreement with other authors our experimental results show that calcitonin inhibits clasts but by a reduced cellular resorption activity of osteoclasts. Bone formation is not affected by calcitonin in intact as well as in parathyroidectomized animals. On the contrary bone mineralization is clearly improved under calcitonin administration in parathyroidectomized rats. This favourable effect is probably caused by a direct hormonal influence on calcium transport in the osteoblast.

Animals↗
PubMed1976

Trismus resulting from central nervous system lesion.

Three cases of unusual trismus are reported, occurring in patients with lesions of the central nervous system. On the basis of the clinical and electromyographical findings and observation of the course of the trismus this is interpreted as a symptom of a lesion of the brain stem, causing a dis-synergism of the masticatory muscles.

Accidents, Traffic↗
PubMed1976

[Differential diagnosis of cerebral convulsive seizures in the tetanic syndrome].

An analysis of the types of attacks occurring in tetanus patients shows that epileptic attacks are a relatively frequent occurrence in such patients. In patients under anti-epileptic therapy it is readily possible for the clinical picture to be concealed, and this may then result in irreversible damage due to the disturbance of metabolism remaining uninfluenced. It is recommended that the treatment of patients with cerebral attacks should include measures aimed at preventing the occurrence in them of convulsions resulting from the particular metabolic situation in the case of tetanus. What is also pointed out by the authors in their present paper is that tetanus patients treated with anticonvulsives and particularly disposed sufferers from epilepsy may show a deterioration of the metabolic situation and a loss of stability of the vitamin D metabolism, respectively. Accordingly, it is advisable that regular clinical and paraclinical checks be made in the case of the two syndromes referred to above.

Adolescent↗
PubMed1976

[Recent progress in morphology and diagnosis of bone diseases and bone tumors (author's transl)].

1. Bone structure is shaped by a specialized bone cell system comprising osteoblasts, osteocytes and osteoclasts. --2. The function of this bone cell system is impaired by metabolic bone disease altering bone structure, bone mass and mineral content. --3. In metabolic bone disease a striking improvement in morphologic diagnosis could be obtained recently using undecalcified preparations of bone tissue as well as histomorphometric methods. --4. For exact diagnosis and successful therapy of bone tumors interdisciplinary cooperation is mandatory. The advantages of modern morphologic methods are proven helpful in diagnosing benign and malignant bone tumors.

Age Factors↗
PubMed1975

[Polymyositis].

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Adult↗