Search PubMed⌕ Search

Biomedical subjects

S Schuster

Publications and source records attributed to S Schuster.

At least 109 records · Page 6Linked to original sources
PubMed1986

Cloning and expression of the lepidopteran toxin produced by Bacillus thuringiensis var. thuringiensis in Escherichia coli.

The Bacillus thuringiensis var. thuringiensis strain 3A produces a proteinaceous parasporal crystal toxic to larvae of a variety of lepidopteran pests including Spodoptera littoralis (Egyptian cotton leaf worm), Heliothis zeae, H. virescens and Boarmia selenaria. By cloning of individual plasmids of B. thuringiensis in Escherichia coli, we localized a gene coding for the delta-endotoxin on the B. thuringiensis plasmid of about 17 kb designated pTN4. Following partial digestion of the B. thuringiensis plasmid pTN4 and cloning into the E. coli pACYC184 plasmid three clones were isolated in which toxin production was detected. One of these hybrid plasmids pTNG43 carried a 1.7-kb insert that hybridized to the 14-kb BamHI DNA fragments of B. thuringiensis var. thuringiensis strains 3A and berliner 1715. This BamHI DNA fragment of strain berliner 1715 has been shown to contain the gene that codes for the toxic protein of the crystal (Klier et al., 1982). No homologous sequences have been found between pTNG33 and the DNA of B. thuringiensis var. entomocidus strain 24, which exhibited insecticidal activity against S. littoralis similar to that of strain 3A.

Antigens, Bacterial↗
PubMed1985

Blood lymphocyte volumes and diameters in patients with chronic lymphocytic leukemia and normal controls.

The electronic modal lymphocyte volumes of 151 patients with chronic lymphocytic leukemia (CLL) and 305 normal controls were determined by the hydrodynamically focused multi-channel Coulter TF analyser. The mean volumes of the normally distributed groups were 166 +/- 19.3 (range 126-216) fl in patients with CLL and 206 +/- 14.4 (range 126 +/- 246) fl in normal controls. The calculated cell diameters were 6.8 (6.2-7.4) micron and 7.3 (6.8-7.8) micron respectively. Our data do not support previous reports about relations between cell size and clinical stages of the Rai and Binet classifications.

Blood Volume↗
PubMed1983

[Serodiagnosis of Crohn's disease].

Three serological tests, recommended as being of diagnostic value for Crohn's disease, were evaluated in 39 patients with Crohn's disease and--as controls--in 27 patients with ulcerative colitis, 45 healthy persons and 65 patients with inflammatory diseases other than Crohn's disease or ulcerative colitis. The tests were the determination of (1) serum antibodies to pseudomonas-like organisms (PLO) by means of indirect immunofluorescence; (2) agglutinating serum antibodies to 4 strains of anaerobic gram-positive coccoid rods (species of Eubacterium, Peptostreptococcus and Coprococcus); and (3) serum antibodies to perinuclear antigens in buccal mucosa of Crohn's disease patients by immunofluorescence. The results indicate that the occurrence of high-titer antibodies to PLO is reasonably sensitive for Crohn's disease, but has a low specificity, and that antibodies to perinuclear antigens in buccal mucosa have both low sensitivity and specificity. However, the occurrence of agglutinins to 4 strains of anaerobic grampositive coccoid rods is significantly higher in Crohn's disease than in ulcerative colitis, patients with other diseases and healthy controls. Thus the determination of these agglutinins does not discriminate between Crohn's disease and ulcerative colitis; but it is a serodiagnostic adjunct in the diagnosis of chronic inflammatory bowel diseases.

Antibodies, Bacterial↗
PubMed1983

[Metabolic interactions of propyphenazone].

Pretreatment of female Wistar rats with propyphenazone produces a slight shortening of the hexobarbital sleeping time, and high doses of this drug cause a small increase in the relative liver weight, but there occurs no significant change in the N-demethylation of aminophenazone, the O-demethylation of codeine phosphate, the hydroxylation of aniline, the glucuronidation of p-nitrophenol, the cytochrome P-450 concentration and the NADPH-cytochrome c reductase activity in the 9.000 supernatant of liver homogenates. The differences between these properties of propyphenazone and those of aminophenazone and phenazone are discussed with reference to partition coefficients and biotransformation. The findings obtained do not justify the expectation of metabolic drug-drug interactions in case of repeated application of propyphenazone in the framework of a combined therapy.

Animals↗
PubMed1982

Pneumothorax in cystic fibrosis: management and outcome.

We reviewed our experience over the past 12 years to determine the best method of management, to determine the morbidity and the physiologic outcome of medical vs surgical treatment of pneumothorax complicating CF, and to assess the influence of age, sex, and Shwachman scores on survival. Sixty-five patients, ages ranging from 5 to 32 years (mean 18 years). Shwachman scores ranging from 25 to 87 (mean 57), and a male-female ratio of 1:1, experienced 170 pneumothoraces, 93 first episodes, and 77 recurrences, requiring 211 trials of management. All methods of management except needle aspiration resulted in a fair rate of resolution (70 to 100%), but recurrence rates were high for observation (60%), needle aspiration (79%), trocar thoracotomy (63%), tetracycline sclerosis (86%), and silver nitrate sclerosis (43%). The recurrence rates were 12.5% for quinacrine sclerosis and 0% for parietal pleurectomy. Quinacrine sclerosis and parietal pleurectomy were the most effective methods of management. There was no significant difference in pulmonary function before pneumothorax and after pleural sclerosis or parietal pleurectomy. Age, sex, and severity of pulmonary disease were all independent variables influencing prognosis. Severity of disease, rather than the occurrence of a pneumothorax, appears to be the major cause of death. We recommend that quinacrine sclerosis should be considered for management of the first pneumothorax, and parietal pleurectomy if it fails.

Adolescent↗
PubMed1981

[Metabolic interactions of promethazine (author's transl)].

Owing to enzyme induction, the pretreatment of female Wistar rats with promethazine (Prothazin, Atosil) produces a shortening of the hexobarbital sleeping time, a slight increase in the relative liver weight, an increase in the N-demethylation of aminophenazone, the O-demethylation of codeine phosphate, the O-demethylation of p-nitroanisol, the glucuronidation of p-nitrophenol and the NADPH-cytochrome c reductase activity in the 9.000 g supernatant of liver homogenates. Particularly striking are the strong stimulation of the N-demethylation and the also potentiated [in contrast to the findings obtained with dioxopromethazine (Prothanon)] UDP-glucuronyltransferase activity, whereas the cytochrome P-450 concentration shows a slight trend toward increase, but this is not statistically significant. The findings obtained justify the expectation of drug interactions in case of repeated application of promethazine in the framework of a combined therapy.

Animals↗
PubMed1980

Polyalveolar lobe: anatomic and physiologic parameters and their relationship to congenital lobar emphysema.

Polyalveolar lobe is one of the recently described pathological entities that can give rise to congenital lobar emphysema (CLE). In polyalveolar lobe, the total alveolar number as determined by microscopic point-counting of randomly taken lung sections is increased three to fivefold. The airways and arteries are normal for age in number, size and structure. Follow-up over 10-20 yr of patients operated upon for congenital lobar emphysema, including those of polyalveolar lobe etiology shows that these patients do well clinically. All patients have some pulmonary function abnormalities, specifically a decrease in airway conductance, and forced expiratory volume. It is not possible to distinguish patients with polyalveolar lobes from other CLE patients on the basis of pulmonary function data. All patients had normal lung volumes and vital capacities, despite losing 8%-20% of their pulmonary parenchyma. Based on compensatory lung growth, it may be preferable to operate earlier, rather than later in these cases.

Child, Preschool↗
PubMed1980

Lung growth and airway function after lobectomy in infancy for congenital lobar emphysema.

To characterize the outcome of lobectomy in infancy and the low expiratory flows which persist after lobectomy for congenital lobar emphysema, 15 subjects with this history were studied at age 8-30 yr. Total lung capacity was normal in all, but higher values (P < 0.05) were observed in nine subjects with upper lobectomy than in five subjects with right middle lobectomy. Ratio of residual volume to total lung capacity was correlated (P < 0.05) with the amount of lung missing as estimated from normal relative weights of the respective lobes. Xe(133) radiospirometry in eight subjects showed that the operated and unoperated sides had nearly equal volumes at total lung capacity, but that the operated side was larger than the unoperated side at residual volume. Perfusion was equally distributed between the two sides. Similar findings were detected radiographically in four other subjects. Forced expiratory volume in 1 s and maximal midexpiratory flow rate averaged 72 and 45% of predicted, respectively. Low values of specific airway conductance and normal density dependence of maximal flows in 12 subjects suggested that obstruction was not limited to peripheral airways. Pathologic observations at the time of surgery and morphometry of the resected lobes were not correlated with any test of pulmonary function. These data show that lung volume can be completely recovered after lobectomy for congenital lobar emphysema in infancy. The volume increase occurs on the operated side, and probably represents tissue growth rather than simple distension. The response to resection is influenced by the particular lobe resected and may be associated with decreased lung recoil near residual volume. Low expiratory flows in these subjects could be explained by several mechanisms, among which a disproportion between airway and parenchymal growth in infancy (dysanaptic growth) is most compatible with our data.

Adolescent↗
PubMed1980

[Metabolic interaction of valproic acid (author's transl)].

Valproic acid produces a marked competitive inhibition of the aminophenazone N-demethylation and the codeine phosphate O-demethylation by 9000 g-supernatant of rat liver homogenates, but it exerts virtually no effect on the aniline hydroxylation and the p-nitrophenol glucuronidation which are slightly inhibited only if its tenfold amount is allowed to react on the substrate.

Aminopyrine↗
PubMed1979

Bronchial artery embolization in cystic fibrosis; technique and long-term results.

Severe bronchial hemorrhage in 13 patients with cystic fibrosis was treated by catheter embolization of bronchial arteries. Indications were either excessive bleeding persisting for several days, or bleeding serious enough to interfere with pulmonary drainage and recurring over weeks or months. In follow-up ranging from one to 30 months, cessation of major bleeding was achieved in 12 of 13 patients (93%), although 5 of 13 patients (40%) did have recurrence of minor hemoptysis. No neurologic or other major complications were encountered. However, there are potential risks and this approach at present should be limited to patients with life-threatening bleeding and carried out only by experienced angiographers.

Adolescent↗