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Biomedical subjects

H Winkler

Publications and source records attributed to H Winkler.

At least 199 records · Page 11Linked to original sources

Dexamethasone induces an increased biosynthesis of chromogranin A in rat pituitary gland.

The influence of dexamethasone on the regulation of the biosynthesis of chromogranins A and B, two proteins originally described in adrenal chromaffin granules, was investigated in the rat pituitary gland. Dexamethasone increased chromogranin A levels and its corresponding mRNA in a dose-dependent manner. Induction of chromogranin A occurred with a time-lag of 24 h. As shown by immunohistochemistry, chromogranin A was present in control and dexamethasone-treated rats in gonadotrophic cells only. Chromogranin B, secretogranin II and the respective pituitary hormones co-stored with chromogranin A were not changed by dexamethasone. Thus dexamethasone selectively increased chromogranin A levels in gonadotrophic cells.

Animals↗

[Preclinical and clinical primary therapy of multiple fractures of the leg].

A successful clinical primary treatment of multiple fractures of the lower extremities depends on a rapidly administered preclinical therapy with short care periods. The early biomechanically stable osteosynthesis leads to improved haemodynamics by haemostasis and elimination of pain. Early functional treatment and hypostasis therapy will promote the prophylaxis of pneumonia. 14 patients with multiple fractures of the lower extremities were treated by the concept that provides for preclinical emergency therapy and clinical primary treatment as a unit.

Adolescent↗

Demonstration of immunochemical identity between the synaptic vesicle proteins synaptin and synaptophysin/p38.

The synaptic vesicle proteins synaptin and synaptophysin/p38 were shown to be immunochemically identical. Western immunoblot analysis of Triton X-100 extracts from rat brain showed that polyclonal polyspecific anti-synaptin antibodies and monoclonal antibody SY38 against synaptophysin both reacted with a band of 38 kDa. In two-dimensional immunoblots of chromaffin granule membranes from bovine adrenal medulla anti-synaptin and anti-synaptophysin antibodies also recognized the same component. Finally, in a Western immunoblotting experiment SY38 reacted with an immuno-isolated synaptin antigen.

Adrenal Medulla↗

Two-dimensional immunoblotting analysis and immunocytochemical localization of the secretory polypeptide 7B2 in adrenal medulla.

The soluble proteins of bovine chromaffin granules were subjected to 2D-electrophoresis followed by immunoblotting with an antiserum against the pituitary peptide 7B2. One immunoreactive spot was visualized at a position corresponding to a molecular weight of 24,000 and to a pI of 5.2. Using peroxidase-antiperoxidase (PAP) pre-embedding immunocytochemical technique for electron microscopy, 7B2 has been localized within secretory granules with diameters of approximately 115 and 190 nm in noradrenergic and adrenergic cells respectively. These data establish that in chromaffin granules 7B2 represents a minor component of the acidic proteins which include the chromogranins A and B, secretogranin II and the enkephalin-containing peptides.

Adrenal Medulla↗

Processing of chromogranin A within chromaffin granules starts at C- and N-terminal cleavage sites.

Specific antisera were raised against synthetic peptide fragments of bovine chromogranin A. The soluble proteins of bovine chromaffin granules were subjected to two-dimensional immunoblotting with these antisera. The endogenous breakdown products of chromogranin A gave distinct patterns of immunostaining which enabled us to correlate these peptides with defined regions of the chromogranin A molecule. The results establish that within chromaffin granules degradation of chromogranin A by the endogenous proteases can start either at the C- or the N-terminal site.

Animals↗

Co-ordinate control of synthesis of mitochondrial and non-mitochondrial hemoproteins: a binding site for the HAP1 (CYP1) protein in the UAS region of the yeast catalase T gene (CTT1).

Control of expression of the Saccharomyces cerevisiae CTT1 (catalase T) gene by the HAP1 (CYP1) gene, a mediator of heme control of mitochondrial cytochromes, was studied. Expression of a CTT1-lacZ fusion in a hap1 mutant showed that the CTT1 promoter is under HAP1 control. As demonstrated by a gel retardation assay, the HAP1 protein binds to a heme control region of the CTT1 gene. This binding in vitro is stimulated by hemin. The HAP1-binding sequence was localized by using DNA fragments spanning different regions, by DNase I footprinting and by methylation interference of DNA-protein binding. The binding site was compared to the HAP1-binding sequences previously characterized in detail (UAS1CYC1, UASCYC7). There is strikingly little similarity between the three sequences, which have only four of those 23 bp in common which are protected from DNase I digestion. However, the pattern of major and minor groove contacts in the complex is quite similar in all three cases. The results obtained show that there is true co-ordinate control of expression of mitochondrial cytochromes and at least some extra-mitochondrial hemoproteins. Heme acts as a metabolic signal in this coordination, which is mediated by the HAP1 protein.

Base Sequence↗

Immunological characterization of a membrane glycoprotein of chromaffin granules: its presence in endocrine and exocrine tissues.

A glycoprotein was isolated from detergent solubilized membranes of bovine chromaffin granules by high-performance liquid chromatography. Specific antisera raised against this glycoprotein reacted in one- and two-dimensional immunoblots with a heterogeneous component with a pI of 4.2-4.7 and Mr 100,000. The antiserum against bovine glycoprotein II cross-reacted with an analogous component in several species. The specific localization of glycoprotein II in chromaffin granules was established by density gradient centrifugation followed by immunoblotting. The antiserum, as shown by one- and two-dimensional immunoblotting, reacted with an analogous antigen in the posterior pituitary, in endocrine (anterior pituitary, parathyroid gland) and exocrine (parotid gland, pancreas) organs. In the pancreas the protein reacting with the antiserum was found in the membranes of zymogen granules. The results demonstrate for the first time that secretory vesicles of endocrine and exocrine tissues have at least one common antigen, i.e. the glycoprotein II. It seems likely that this protein is involved in a basic function common to all secretory vesicles.

Adrenal Medulla↗

Extracorporeal shock wave lithotripsy using a new, compact and portable unit.

We report on the use of a new compact, inexpensive, portable shock wave lithotriptor. To date 40 treatments on 37 patients with different calculi in the upper urinary tract have been performed at our institution with excellent results and no complications. More patients currently are being treated with this machine at additional centers with equally good results.

Animals↗

Immunological studies on the occurrence and properties of chromogranin A and B and secretogranin II in endocrine tumors.

We investigated a variety of endocrine tumors for the presence of chromogranins A and B and secretogranin II. These antigens were identified by one- and two-dimensional immunoblotting and in some cases by immunohistochemistry. An antigen corresponding in electrophoretic behavior to adrenal chromogranin A was present in all types of tumors, including insulinomas, oat cell carcinomas, and Merkel cell tumors of the skin. Chromogranin B had a much more limited distribution. This antigen could not be detected in parathyroid adenomas, oat cell carcinomas, or Merkel cell tumors, either by immunoblotting and immunohistochemistry. The occurrence of secretogranin II was similar to that of chromogranin B, with the exception of a positive reaction in Merkel cell tumors. In benign pheochromocytomas, all three antigens were found consistently; whereas in two of three malignant pheochromocytomas, chromogranin B was absent. Our study establishes that in most cases chromogranins and secretogranin in tumors are identical to the adrenal antigens, but that these antigens are not always stored together. Chromogranin A is the most widely distributed marker for endocrine tumors.

Adrenal Gland Neoplasms↗

In adrenal medulla synaptophysin (protein p38) is present in chromaffin granules and in a special vesicle population.

We have analyzed the properties and subcellular localization of synaptophysin (protein p38) in bovine adrenal medulla. In one-dimensional immunoblotting the adrenal antigen appears identical to synaptophysin of rat synaptic vesicles. In two-dimensional immunoblotting it migrates as a heterogeneous band varying in pI from 4.5 to 5.8. Subcellular fractionation by various sucrose gradients revealed that synaptophysin was present in two different cell particles. More than half of the antigens present in adrenal medulla were confined to special membranes that sedimented both with the "large granules" and with microsomal elements. These membranes could be removed from the large granule sediment by washing. In gradients it equilibrated in regions of low sucrose density. These membranes did not contain any markers for chromaffin granules. Less than half of the amount of synaptophysin present in adrenal medulla copurified with chromaffin granules. Despite several variations in the fractionation scheme synaptophysin could not be removed from chromaffin granules. After washing of granule membranes with alkaline solution synaptophysin still cosedimented in gradients with typical granule markers. The concentration of synaptophysin in membranes of chromaffin granules is low (less than 10%) when compared with synaptic vesicles. It is concluded that in adrenal medulla synaptophysin is present in special membranes, probably in high concentration, and in membranes of chromaffin granules, either in a low concentration in all or in a higher concentration in some of them.

Adrenal Medulla↗

Phylogenetic distribution of peptides related to chromogranins A and B.

The presence of chromogranin-related peptides in a wide range of species was investigated by one and two-dimensional electrophoresis followed by immunoblotting. Antisera against bovine chromogranins A and B and the peptide WE-14 (chromogranin A316-329) were used. Chromogranins were identified by their heat stability, by their electrophoretic behavior, and by immunological cross-reaction with antisera. In all species investigated ranging from mammals to birds, amphibians, fish, and arthropods, chromogranin A- and B-like proteins could be demonstrated. For all species, there was an immunological cross-reaction with antisera against bovine chromogranins. The molecular sizes and isoelectric points of the chromogranins were similar in all species. The antiserum against WE-14 cross-reacted with pig, rat, and chicken chromogranins. It is concluded that the chromogranins A and B have a widespread phylogenetic distribution with a significant conservation of molecular size, isoelectric points, and immunological epitopes. This is consistent with the concept that these peptides have a specific function.

Animals↗

[Küntscher intramedullary nailing of the tibial shaft fracture. A 19-year evaluation].

Marrow nailing developed by Gerhard Küntscher for long tubular bones is an excellent surgical procedure for fractures of the lower leg shaft. It yields outstanding results both with the typical good indications in respect of shape of fracture, localisation and soft tissue conditions and even with atypical borderline and emergency indications where the healing results can be said to be good and satisfactory. Of course long-standing experience is required especially when employing the Küntscher intramedullary nail in the atypical range of indications. This method produces good results even in critical situations if appropriate accompanying measures are taken. Technique, results and complications are described in this article reflecting the experience of 19 years of working with the intramedullary Küntscher nail.

Adult↗