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Biomedical subjects

A Schulz

Publications and source records attributed to A Schulz.

At least 19 recordsLinked to original sources
PubMed1992

Adult polyglucosan body myopathy.

This report describes a sporadic late-onset myopathy in two unrelated adults which was marked by polyglucosan inclusions surrounded by abnormally structured mitochondria, the latter finding a localized, possibly reactive phenomenon. The polyglucosan material was characterized by a battery of histochemical and enzyme histochemical techniques; revealed common antigenicity with Lafora bodies, corpora amylacea and muscle fiber inclusions in types IV and VII glycogenoses; and contained ubiquitin. Additional lectin histochemical and associated digestion preparations disclosed the presence of alpha-glycosyl residues as apparently the sole carbohydrate component in polyglucosan bodies while the above mentioned common antigenicity with Lafora bodies and other inclusions suggests an additional, so far unidentified, protein component.

Atrophy↗
PubMed1991

[Carcinoembryonic antigen in serum and pleural fluid to distinguish between bronchial carcinoma and pleural mesothelioma].

The concentrations of carcinoembryonic antigen (CEA) were measured, partly retrospectively and partly prospectively, in 94 patients with diffuse malignant mesothelioma and in 79 with bronchial carcinoma and pleural involvement. Serum concentrations were measured in all patients, pleural-fluid concentrations additionally in 53 patients of the former and 39 of the latter group. The concentrations were significantly higher in those with bronchial carcinoma (P less than 0.001). The two groups could be distinguished by serum concentrations, using 5.2 ng/ml as the limit, with a sensitivity of 68%, specificity of 98% and a predictive value of 96%. Measurement of CEA in pleural fluid (at a limit of 4.5 ng/ml) had a specificity of 94% and a positive predictive value of 90%, sensitivity being similar to that for serum. The negative predictive value for serum CEA concentration was 79%, for pleural fluid it was 81%. Thus in most cases measurement of CEA in serum and, to a lesser extent in pleural fluid, is a very simple method to exclude mesothelioma with a high degree of certainty. If the CEA concentration is below the stated level, either may be present.

Adult↗
PubMed1991

Efficacy and tolerability of a long-acting intramuscularly injectable depot preparation of bromocriptine: the results of a double blind study.

The tolerability and efficacy of a long-acting im applicable form of bromocriptine (Parlodel LAR) was tested in a double-blind approach in 20 patients with hyperprolactinemia or prolactinoma, 17 of them complaining of persistent side effects on oral treatment with dopamine agonists. The study-code revealed similar characteristics for age, sex, weight, clinical symptoms and previous therapy in both groups but prolactin serum levels were higher in the verum group even though the difference was not significant. In all 10 patients receiving Parlodel LAR prolactin serum concentrations were significantly suppressed and tumor size was reduced in 5 of the 9 patients with visible tumors when controlled after 28 days. In contrast, no significant change in serum prolactin levels was observed in the placebo group and tumor size of all visible tumors was not altered. Side effects typically reported for dopamine agonists started 3 h after application in the verum group and were significantly different to the unspecific side effects reported in the placebo group during the first 72 h. Thereafter systemic tolerability was indistinguishable between both groups. The local tolerability at the injection site was excellent for both, Parlodel LAR and placebo.

Adolescent↗
PubMed1991

[Interventional radiologic procedures in complete occlusions of long stretches of the iliac artery].

15 completely occluded iliac arteries (five cases over 10 cm, 8 cases between 5 and 10 cm and two cases below 5 cm) were reviewed for their interventional management, technical results and complications. The procedure was successful in 14 of 15 cases (93%). In six cases we performed local thrombolysis before PTA. In the patient group with "only PTA" the treatment had to be abandoned in one case because of the risk of embolism. Two patients suffered from a distal embolism of the same side and one patient from an ipsi- and contralateral embolism. A stent implantation was necessary in one patient. In the group of patients with prior local thrombolysis there was no complication nor was there an indication for a stent-implantation. Hence, we conclude that a primary local lysis with a consecutive PTA is an appropriate treatment of complete long occlusions of the iliac artery.

Adult↗
PubMed1991

[Deviations of the central ray in standardized bite-wing radiographs].

Interpretation of serial radiographs without sufficient information of projection geometry is hardly possible. We obtained 51 pairs of bite-wing radiographs in 12 patients by use of a modified filmholder (Duckworth et al. 1983). Two orthodontic wires of different profile, placed coaxially on the perpendicular, cast shadows on the film, which were differentiated by their respective shape. By placing each wire a known distance from the film plane, the angular difference between the perpendicular to the film and the actual direction of the central ray could be calculated. In 63% of pairs the angular deviation of the central rays between the serial exposures was below 0.9 degrees. The results of the present study show that utilization of this type of device can provide radiographs of sufficient quality to allow their use in image subtraction.

Humans↗
PubMed1990

[Immunohistochemical C5b-9-complement complex demonstration in early stages of myocardial necroses using paraffin sections].

With conventional staining techniques it was nearly impossible to differentiate with certainty between early ischemic myocardial lesions, autolytic changes and intact myocardium without a nuclear section. In 1986 it was introduced an immunohistochemical method, which presented C5b-9 Complement Complex as a necrosis marker in cryostat sections. Our further development of this process has resulted in a technique for application on routine paraffin sections: C5b-9 Complement Complex is particularly well-suited for the exact and autolytically insensitive presentation of disseminated necroses of fiber bundels and single fibers of myocardium. The application of the technique on paraffin sections will lead to the use of the same in forensic medicine routine diagnostics of early ischemic myocardial lesions, even in cases of "sudden" cardiac death.

Complement C5↗
PubMed1990

Immunoelectron microscopy of osteonectin and type I collagen in osteoblasts and bone matrix.

The pathway of production, secretion, and extracellular deposition of type I collagen and osteonectin was studied by immunoelectron microscopy using respective polyclonal antibodies. Protein A gold and immunogold methods yielded to similar results in human callus tissue used as a model of bone formation. The intracellular distribution of osteonectin in active osteoblasts is found as a faint immunolabeling of vesicular Golgi fields and some lamellae of rough endoplasmic reticulum. A more intensive labeling occurs in opaque cytoplasmic vesicles pointing to the process of secretion as some of the vesicles are connected with the basal cell membrane. Our type I collagen antibody did not label the respective intracellular compartments. Extracellularly, the type I collagen antibody showed a continuous labeling from the immature subcellular osteoid to the mineralized bone. Osteonectin antibodies were bound first to the deeper layer of osteoid maturation with intensity increasing below the mineralization front. Osteonectin is thought to be associated with mineralization of bone matrix.

Antibodies↗
PubMed1990

Stereospecific production of the herbicide phosphinothricin (glufosinate) by transamination: isolation and characterization of a phosphinothricin-specific transaminase from Escherichia coli.

An aminotransferase capable of transaminating 2-oxo-4-[(hydroxy)(methyl)phosphinoyl]butyric acid to L-phosphinothricin [L-homoalanine-4-yl-(methyl)phosphinic acid], the active ingredient of the herbicide Basta (Hoechst AG), was purified to apparent homogeneity from Escherichia coli K-12. The enzyme catalyzes the transamination of L-phosphinothricin and various analogs with 2-ketoglutarate as the amino group acceptor. The transaminase has a molecular mass of 43 kilodaltons by sodium dodecyl sulfate-gel analysis and an isoelectric point of 4.35. The enzyme was most active in the high-pH region, with a maximum at pH 8.0 to 9.5, and had a temperature optimum of 55 degrees C. Heat stability was observed up to 70 degrees C. Substrate specificity studies suggested that the enzyme is identical with the 4-aminobutyrate:2-ketoglutarate transaminase (EC 2.6.1.19). The first 30 amino acids of the N terminus of the protein were determined by gas phase sequencing. The transaminase was immobilized by coupling to the epoxy-activated carrier VA-Biosynth (Riedel de Haen) and used in a column reactor for the continuous production of L-phosphinothricin. The enzyme reactor was operated for 7 weeks with only a slight loss of catalytic capacity. Production rates of more than 50 g of L-phosphinothricin per liter of column per h were obtained.

Aminobutyrates↗
PubMed1990

Stereospecific production of the herbicide phosphinothricin (glufosinate) by transamination: cloning, characterization, and overexpression of the gene encoding a phosphinothricin-specific transaminase from Escherichia coli.

We have cloned the gene encoding a 43-kilodalton transaminase from Escherichia coli K-12 with a specificity for L-phosphinothricin [L-homoalanine-4-yl-(methyl)phosphinic acid], the active ingredient of the herbicide Basta (Hoechst AG). The structural gene was isolated, together with its own promoter, and shown to be localized on a 1.6-kilobase DraI-BamHI fragment. The gene is subject to catabolite repression by glucose; however, repression could be relieved completely when 4-aminobutyrate (GABA) served as the sole nitrogen source. The regulation pattern obtained and a comparison of the restriction map of the initially cloned 15-kilobase SalI fragment with the physical map of the E. coli K-12 genome suggest that the cloned gene is identical with gabT, a locus on the gab gene cluster of E. coli K-12 which codes for the GABA:2-ketoglutartate transaminase (EC 2.6.1.19). A number of expression plasmids carrying the isolated transaminase gene were constructed. With these constructs, the transaminase expression in transformants of E. coli could be increased up to 80-fold compared with that in a wild-type control, and the transaminase constituted up to 20% of the total soluble protein of the bacteria. Thus, the protein crude extracts of the transformants could be used, after a simple heat precipitation step, for the biotechnological production of L-phosphinothricin in an enzyme reactor.

Aminobutyrates↗
PubMed1990

Molecular analysis of two genes of the Escherichia coli gab cluster: nucleotide sequence of the glutamate:succinic semialdehyde transaminase gene (gabT) and characterization of the succinic semialdehyde dehydrogenase gene (gabD).

We have characterized two genes of the Escherichia coli K-12 gab cluster, which encodes the enzymes of the 4-aminobutyrate degradation pathway. The nucleotide sequence of gabT, coding for glutamate:succinic semialdehyde transaminase (EC 2.6.1.19), alternatively known as 4-aminobutyrate transaminase, was determined. The structural gene consists of 1,281 nucleotides specifying a protein of 426 amino acids with a molecular mass of 45.76 kDa. The protein shows significant homologies to the ornithine transaminases from Saccharomyces cerevisiae and from rat and human mitochondria. Three functionally and structurally important amino acid residues of the transaminase were identified by sequence comparison studies, and evolutionary relationships of the aminotransferases are discussed. The gabD gene, encoding succinic semialdehyde dehydrogenase (EC 1.2.1.16), was cloned and shown to be located adjacent to the 5' end of gabT. Expression studies with subfragments of the initially cloned DNA region revealed a maximal size of 1.7 kb for gabD. Both genes are cotranscribed from a promoter located upstream of gabD.

4-Aminobutyrate Transaminase↗
PubMed1990

[Postoperative ventilation in non-intubated patients with iron lung versus conventional ventilation].

Postoperative ventilation using a steel lung is an alternative to conventional ventilation through an endotracheal cannula. Both methods were compared in two groups of patients undergoing major abdominal surgery. Group A was ventilated using a Servo Ventilator 900C, whereas group B was ventilated using a newly designed steel lung. The duration of ventilation using the steel lung and that of postoperative intubation were significantly shorter than those used in group A, in spite of a higher anesthesiological and surgical risk in patients in group B. pO2 was significantly increased during ventilation with the steel lung in comparison to conventional ventilation. An automatic classification of EEG activity was used to estimate depth of anesthesia. This showed a close correlation between clinical signs and anesthesiological levels. The spectroanalytical evaluation of ventilation curves allowed the early recognition of spontaneous breathing and determined tidal volumes using steel lung ventilation.

Aged↗
PubMed1990

[Cyclosporine-induced gingival hyperplasia in renal transplant patients].

Cyclosporine-induced gingival hyperplasia was investigated in a clinical study of 80 renal transplant patients. 34% of the patients exhibited at least mild gingival hyperplasia in the anterior, and 9% presented this finding also in the posterior region. No direct correlation was found between the oral dose or the whole blood concentration of cyclosporine and the presence of gingival overgrowth. Young and female patients were at a significantly greater risk of developing cyclosporine-induced gingival hyperplasia than the other patients. The presence of dental plaque or gingival inflammation was not found to be related to the incidence of gingival hyperplasia.

Adolescent↗