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C Schubert

Publications and source records attributed to C Schubert.

At least 73 records · Page 4Linked to original sources
PubMed1994

[Presence of alternatively spliced messenger RNA for HLA-A, -B and -C in platelets].

Recently we demonstrated that platelets contain specific messenger RNA (mRNA) encoding for the transmembrane HLA class I molecule (44 kDa). In this study we analyzed lymphocytes as well as platelets for the presence of alternatively spliced mRNA with deleted transmembrane domain resulting in soluble HLA class I antigens (39 kDa). PCR amplification of lymphocyte RNA led to a product specific for alternatively spliced cDNA corresponding to the presence of soluble HLA in plasma, while this product could not be obtained from platelet mRNA. These results suggest that platelets in contrast to lymphocytes are unable to synthesize soluble HLA antigens via alternative splicing.

Alternative Splicing↗
PubMed1993

[The effect of oligosaccharides on piglets].

Into the starter of weaned piglets 1% lactitol and 0.2% fructo-, isomalto- or galacto-oligosaccharides were added. After an adaptation period of two weeks the piglets were slaughtered 3 hours postprandial. Compared with control animals in the trial groups urea concentrations in the serum and fermentations in the stomach were lowered, stomach emptying rates increased. Higher volumes and contents were measured in the colon, especially in the upper half, and more lactic acid.

Animal Feed↗
PubMed1992

Relapsing bullous staphyloderma.

Relapsing eruptions of bullae rapidly turning into pustules were seen in a 69-year-old woman of good general health. At different times during several months of observation, strains of S. aureus were grown from various lesions, including one (phage group III) producing enterotoxin C. Systemic involvement except for high BSR was absent and repeated blood cultures were negative. Histopathological findings resembled impetigo. Antibiotic treatment was effective. As this disease does not fit into any of the well-known pustular infectious dermatoses, we suggest calling it relapsing bullous staphyloderma.

Aged↗
PubMed1992

[Brain scintigraphy (SPECT) with thallium-201 in primary brain tumors].

We evaluated the role of thallium-201 single-photon emission-computed tomography (SPECT) in diagnosis, differential diagnosis and follow-up of 33 patients with primary brain tumors. 27 of 33 lesions were detectable by Tl-201 SPECT because only two of eight low-grade (grade 1 and 2) astrocytomas showed Tl-201 accumulation up to a tumor to nontumor ratio of 2.6. High grade (grade 3 and 4) astrocytomas showed Tl-201 accumulation in the range of 2.2 up to 13.0 and were different from low-grade astrocytomas. Noninvasive grading of astrocytomas is therefore possible, whereas differential diagnosis of oligodendrogliomas and astrocytomas or meningiomas was not possible with Tl-201. In the follow-up of six patients, we could demonstrate, that tumor progression is correlated with increasing and tumor regression with decreasing Tl-201 accumulations. This functional changing proceed morphological findings in CT. But vanishing of Tl-201 accumulation during therapy does not mean vanishing of tumor as could be demonstrated by follow-up.

Adult↗
PubMed1991

Cloning and sequencing the urocanase gene (hutU) from Pseudomonas putida.

A clone harbouring the entire urocanase gene (hutU) was obtained from a genomic library of Pseudomonas putida using oligonucleotide probes synthesised on the basis of known flanking sequences. One subunit of urocanase consists of 556 amino acids and has a molecular mass of 60,771 Da.

Amino Acid Sequence↗
PubMed1991

Minimization of indomethacin-induced reduction in renal function by misoprostol.

A prospective, randomized, open-label, triple crossover comparison of the effects of indomethacin, misoprostol, or the combination, on renal function was performed to assess the ability of an oral prostaglandin E analogue, misoprostol, to minimize indomethacin-induced decline in renal function in middle-aged women. Twelve healthy women (mean age: 60.5 +/- 1.6 yr) with normal renal function (serum creatinine: 81 +/- 9 umol/L) were studied; six women were normotensive, and six women were hypertensive with their blood pressure controlled with 50-mg hydrochlorothiazide daily. All patients were placed on a 2-g sodium daily diet for 2 weeks before initiation of the study. The subjects were prospectively randomized to receive each of three 4-day treatments of indomethacin (25 mg q 6hr), misoprostol (200 mcg q 6hr), or the combination of drugs with a 4-day washout between each treatment period. Measurements of GFR (urine accumulation of 99mTc-DTPA) and RPF (serum disappearance 131I-Hippuran), and urine collections for electrolytes were obtained before the first treatment period and on the fourth day of each treatment period. Three of the six hypertensive patients and three of the six normotensive patients had a decrease (greater than 10%) in GFR associated with indomethacin therapy. When misoprostol was given with the indomethacin, four of these six patients did not experience a decline in GFR (baseline GFR for six patients: 75.4 +/- 6.6 mL/min/1.73m2, GFR after indomethacin: 57.8 +/- 9.5 mL/min/1.73m2, GFR with combination of indomethacin and misoprostol: 69.7 +/- 3.5 mL/min/1.73m2. RPF was not consistently altered by subacute/chronic dosing of indomethacin, misoprostol, or the combination of the drugs. The authors conclude that misoprostol ameliorates indomethacin-induced renal dysfunction in salt-restricted and diuretic-treated middle-aged women with normal serum creatinine.

Alprostadil↗
PubMed1991

[Behavior of the other eye in measuring fixation disparity].

In the subjective measurement of FD, the proband fuses contours presented in the peripheral macular areas of both eyes ('fusion lock'). The position of both eyes relative to each other is monitored by means of two haploscopically seen vertical lines presented in the central visual field, one above and one below a binocularly seen horizontal line. The subject is instructed to shift one of the vertical lines horizontally until the two are aligned, while fixating their intersection with the horizontal line. It has recently been questioned whether the foveolae really are pointed at the perceived intersection. To investigate this matter, we registered the position of one eye while intermittently covering the fellow eye, while the subject maintained fixation of the intersection. We found slight differences in monocular eye position depending on the presence or absence of fusion in the macular periphery, confirming earlier findings in part. These differences were more pronounced in the nondominant eye.

Adult↗
PubMed1991

Effects of temperature on the coupled activities of the vanadate-sensitive proton pump from maize root microsomes.

The mechanism by which proton transport is coupled to ATP hydrolysis by vanadate-sensitive pumps is poorly understood. The effects of temperature on the activities of the vanadate-sensitive ATPase from maize (Zea mays) roots were assessed to provide insight into the coupling mechanism. The initial rate of proton transport had a bell-shaped dependence on temperature with an optimal range between 20 and 30 degrees C. However, the rate of vanadate-sensitive ATP hydrolysis increased as the temperature was raised from 4 to 43 degrees C. The differential sensitivity of proton transport to temperatures above 30 degrees C was also observed when the ATPase was reconstituted into dioleoylphosphatidylcholine vesicles. Inhibition of proton transport with temperatures above 30 degrees C was associated with higher rates of proton leakage from the membranes. In addition, proton transport was more inhibited than ATP hydrolysis at temperatures below 10 degrees C. Reduced rates of proton transport at lower temperatures were not associated with higher rate of proton conductivity across the membranes. Therefore, the preferential inhibition of proton transport at temperatures below 10 degrees C may reflect an effect of temperature on the coupling between proton transport and ATP hydrolysis within the vanadate-sensitive ATPase.

Journal Article↗
PubMed1991

Inflammatory properties of neutrophil-activating protein-1/interleukin 8 (NAP-1/IL-8) in human skin: a light- and electronmicroscopic study.

Neutrophil-activating protein-1/interleukin 8 (NAP-1/IL-8), purified to homogeneity from lipopolysaccharide-stimulated human peripheral blood monocytes, was injected intracutaneously into human skin. Sequential biopsy specimens were taken in order to investigate the sequence of ultrastructural changes induced by the cytokine. Whereas intracutaneous injection of 100 ng of NAP-1/IL-8 per site caused no macroscopic changes, by histology infiltration with polymorphonuclear leukocytes (PMN) and monocytes was present within 1 h and increased at 3 and 5 h. No lymphocyte infiltration was noted. The first ultrastructural changes (30 min) consisted of the presence of cytoplasmic 7-nm microfilament bundles, as well as numerous protrusions of the luminal plasma membrane of endothelial cells (EC). As a striking feature, multiple 100- to 160-nm electron lucent vesicles could be observed in the EC cytoplasm. These structures differed from plasmalemmal vesicles and suggest secretory activity. When PMN and monocytes appeared in the vascular lumen (1 h and later), the number of 100-160-nm electron-lucent vesicles had decreased significantly. In contrast to C5a-injected skin sites, mast cell degranulation was absent.

Complement C5a↗
PubMed1991

[Small papular tumors of the perifollicular and perivascular connective tissue of the head and neck area].

The clinical picture of perifollicular benign tumors resemble that of juvenile warts, but the histopathology is completely different. Three different forms of perifollicular tumors, pure or mixed, have been observed. We report a fourth, previously unrecorded form, named perivascular fibroma from its histological appearance. The histological findings indicate a possible inflammatory etiology, as is also suggested by perifollicular fibroma, whereas postinflammatory signs are absent in trichodiscoma and fibrofolliculoma. The prognosis after removal of these tumors is favorable.

Adult↗
PubMed1990

Evidence for and subcellular localization of a ca-stimulated phospholipase d from maize roots.

Autolytic lipid changes in corn (Zea mays L.) root crude homogenates and isolated membranes were examined by the use of high performance thin-layer chromatography. In the absence of added CaCl(2), losses in phosphatidylcholine and other phospholipids corresponds to increase in fatty acids without the accumulation of either phosphatidic acid or lyso-phosphatidylcholine. However, in the presence of 1 millimolar CaCl(2), phosphatidylcholine concentrations declined more rapidly with an immediate increase in phoshatidic acid, and slower rate of fatty acid accumulation. Autolytic phospholipid degradation yielded primarily free fatty acids in the absence of Ca and phosphatidic acid in the presence of 1 millimolar CaCl(2), suggesting the presence of an acyl hydrolase and phospholipase D activities. Differential centrifugation studies indicate that 50 to 80% of the crude homogenate's phospholipase D activity is membrane-bound. Density centrifugation experiments suggest that the membrane-bound phospholipase D activity is localized primarily on mitochondrial membranes.

Journal Article↗
PubMed1989

Transendothelial cell diapedesis of neutrophils in inflamed human skin.

The mode of extravasation of neutrophils (PMNs) in cutaneous inflammation was studied in sequential biopsy specimens taken from human skin. Inflammatory skin reactions were produced by intracutaneous injection of endogeneous mediators of inflammation--C5ades arg, LTB4, neutrophil-activating peptide (NAP) and interleukin-1 (IL-1). Within 30 min after injection neutrophils were observed in close contact with endothelial cells of postcapillary venules and, following cytoplasmic engulfment, the cells were found to be transported transcellulary through the endothelial layer. In a total of 20 biopsy specimens taken at various times, cell migration via interendothelial gaps was absent. Instead, the transcellular pathway appeared to be the first and foremost mode of diapedesis. During this migratory process PMNs lacked signs of degranulation and numerous electron-lucent vesicles and secondary lysosomes were found. In addition, coated pits present on leukocyte as well as endothelial-cell membranes were indicative of receptor-mediated endocytotic processes.

Cell Movement↗
PubMed1989

[Postoperative results and follow-up of thoracic aortic diseases using magnetic resonance tomography].

Operations of the thoracic aorta for aneurysms, dissections, or congenital malformations may lead to early or late complications. Therefore, postoperative control for documentation of the surgical results, for exclusion of early changes and for comparison with later controls is mandatory. To demonstrate that magnetic resonance imaging (MRI), which we already had used with good results for preoperative studies is also able to detect postoperative abnormalities, we examined 30 patients with thoracic aortic disease (20 male, 10 female, mean age 53 +/- 13.7 years) with this diagnostic tool. There were 19 arteriosclerotic aneurysms, 10 dissections, and one aortic tumor. With MRI it was possible in all patients to visualize the results of the surgical treatment postoperatively. Early postoperative complications could be excluded, or demonstrated in one case of a retrograde aortic dissection or a hematopericardium. These pathological findings could also be shown by arterial digital subtraction angiography or echocardiography. Using MRI for follow-up of aortic dissections, the development of an aneurysm of the aortic root in a Marfan-patient could be detected. In all these patients, it was possible to differentiate true and false lumen and to detect the origin of major side branches. The diagnostic advantages of MRI, which we compared with other imaging methods, as echocardiography, computed tomography or angiography are that postoperative complications of thoracic aortic aneurysm surgery can be reliably detected and visualized in 3 different planes. Non-invasiveness, the omission of ionizing radiation and no risk of contrast media application underline that magnetical resonance imaging is an ideal method for follow-up after operation of the thoracic aorta.

Aortic Dissection↗
PubMed1989

Pleomorphic T-cell lymphoma and large-cell anaplastic lymphoma of the skin. A morphological, immunophenotypical, and ultrastructural study of two typical cases.

Pleomorphic T-cell lymphoma and large-cell anaplastic lymphoma are recently defined lymphoma types that both occur in the skin. This report outlines the characteristics of these lymphomas and describes the clinical, histological, immunological, and ultrastructural features as seen in two typical case histories. Cutaneous T-cell lymphomas other than mycosis fungoides and Sézary syndrome are heterogeneous; they deserve further scientific attention to obtain data about their natural history and their response to therapy.

Aged↗
PubMed1989

Regression of left ventricular hypertrophy under ramipril treatment investigated by nuclear magnetic resonance imaging.

Thirty-two hypertensive subjects with diastolic blood pressure greater than 95 mm Hg were treated with ramipril over a period of 3 months. To determine the effective decrease of blood pressure and for reliable and reproducible demonstration of regression of myocardial hypertrophy during ramipril treatment, we performed parallel measurements with magnetic resonance imaging (MRI) and echocardiography. Measurements were carried out before treatment, 4 h after the first dose, and after 14 days and 3 months of treatment. MRI slices showed a significant decrease of interventricular septal thickness from 19.57 to 15.20 mm, whereas echocardiography demonstrated an equivalent decrease from 18.78 to 14.57 mm. At each measuring point, quantification of wall thickness was performed three times and the means were calculated. The septum and the posterior wall of the left ventricle were also measured at three different points. The values were obtained with negligible scatter and the changes with ramipril treatment were highly significant (p less than 0.001). A concomitant decrease of blood pressure was also observed. The therapeutic aim to reduce diastolic blood pressures below 90 mm Hg was achieved in all patients. In addition to the significant reduction in blood pressure, the angiotensin converting enzyme (ACE) inhibitor ramipril caused a significant regression of pathologic left ventricular hypertrophy demonstrated by magnetic resonance imaging and echocardiography.

Adult↗
PubMed1988

Effect of systemic pH on pHi and lactic acid generation in exhaustive forearm exercise.

To investigate whether changes in systemic pH affect intracellular pH (pHi), energy-rich phosphates, and lactic acid generation in muscle, eight normal volunteers performed exhaustive forearm exercise with arterial blood flow occluded for 2 min on three occasions. Subjects ingested 4 mmol/kg NH4Cl (acidosis; A) or NaHCO3 (alkalosis; B) or nothing (control; C) 3 h before the exercise. Muscle pHi and phosphocreatine (PCr) content were measured with 31P-nuclear magnetic resonance (31P-NMR) spectroscopy during exercise and recovery. Lactate output during 0.5-7 min of recovery was calculated as deep venous-arterial concentration differences times forearm blood flow. Before exercise, blood pH and bicarbonate were lower in acidosis (7.303 +/- 0.009, 18.6 +/- 0.5 meq/l) than alkalosis (7.457 +/- 0.010, 32.2 +/- 0.7 meq/l) and intermediate in control (7.389 +/- 0.007, 25.3 +/- 0.6 meq/l). Lactic acid output during recovery was less with A (245 +/- 39 mumol/100 ml) than B (340 +/- 55 mumol/100 ml) (P less than 0.05) and intermediate in C (293 +/- 31 mumol/100 ml). PCr utilization and resynthesis were not affected by extracellular pH changes. pHi did not differ before exercise (A, 7.04 +/- 0.01; B, 7.09 +/- 0.01; C, 7.06 +/- 0.01) or at its end (A, 6.28 +/- 0.07; B, 6.28 +/- 0.11; C, 6.31 +/- 0.09). Hence systemic acidosis inhibited and alkalosis stimulated lactic acid output. These findings suggest that systemic pH regulates cellular acid production, protecting muscle pH, at the expense of energy availability.

Adult↗