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Biomedical subjects

D Krause

Publications and source records attributed to D Krause.

At least 19 recordsLinked to original sources
PubMed1992

Pattern of glucose transporter (Glut 1) expression in embryonic brains is related to maturation of blood-brain barrier tightness.

A constant supply of blood-borne glucose is vital to cerebral metabolism. Although transport of glucose into the nervous tissue, effectively separated from the blood by a functional barrier (the blood-brain barrier, BBB), is one of the essential properties of the cerebral endothelium, little is known about its metabolic regulation and developmental expression in the BBB. In this study we provide evidence by immunocytochemistry that the pattern of the brain endothelial glucose transporter in rat brains (BBB-GT), immunologically homologous with the human hepatoma (G2), human erythrocyte transporter (Glut 1), changes with BBB maturation. While the neuroepithelium at embryonic days 12 and 13 shows a high incidence of immuno-detectable BBB-GT, vascularisation of the cerebral anlage and subsequent development of vascular tightness, as evidenced by intravascularly applied horseradish peroxidase and fluorescinated dextrans, is accompanied by a significant reduction of BBB-GT expression in neuroepithelial cells and confinement of BBB-GT expression to the cerebral endothelium. Immunoblots and Northern blots of embryonic brain homogenates corroborate this change in BBB-GT expression in the brain anlage at the time of BBB maturation. However, low molecular weight glucose transporters, presumed to be of non-endothelial origin, are less dramatically reduced. The development of BBB tightness, therefore, seems to play a pivotal role in the pattern of BBB-GT expression during brain differentiation.

Animals↗
PubMed1992

Development of a sensitive peptidase assay: in search of cell associated proteases responsible for the cleavage of preproTGF alpha.

A radiometric assay has been developed for the detection of proteolytic activity capable of releasing transforming growth factor alpha (TGF alpha) from its membrane bound precursor. The assay is dependent upon the separation by thin layer chromatography of hydrolytic products of a nonapeptide substrate containing a radioactive iodinated tyrosine residue as a reporting group N-terminal to an octapeptide which is cognate to the N-terminal cleavage sequence of TGF alpha. We describe the selectivity of the peptidase assay with commercially purified proteases and with cell-associated peptidases, its exquisite sensitivity, and its applicability to defining peptidase activity, which may be responsible for the processing of the membrane-bound prepro TGF alpha. The activity of two different elastases had different profiles which thus may be of use in characterizing them. The characteristics of the intact and extracted HeLa cell assay with respect to time, cell density, and peptidase concentration are defined, as are conditions needed to remove endogenous, confounding, proteolytic activity from the serum used to support cell culture. Intact HeLa cell cultures exhibit both exo- and endo-peptidase activity at approximately equal levels in both sparse and dense monolayer culture without relationship to cell density, and at a level equal to 1-2% of total cell activity of these enzyme classes.

Amino Acid Sequence↗
PubMed1992

[Salvaging a mass grave from 1945--Lieberose Labor Camp of the Sachsenhausen concentration camp].

It is reported about a recovering a common grave of 577 skeletons from 1945. Investigations of the age of the victims, the cause of death etc. were carried out. There were gunshot fractures at 541 skeletons. In 93.7% out of all cases there were gunshot fractures of the skull and the cervical vertebra. Difficulties arose from root interpretations in addition to intertwinings owing to the location of the skeletons. Indications to belonging to nationality of the victims are discussed by means the results from AB0-analysis and denture works.

Burial↗
PubMed1992

Investigations on the rectal absorption of chloramphenicol in rabbits after tenside use.

The rectal dose of 16 mg.kg-1 b.w. chloramphenicol (1) without additional tensides did not result in any detectable absorption of effective substance. In contrast, 0.04% of the N-lauroylleucine tenside allowed a rectal absorption having the same effect as that of an injection of the same quantities of effective substance. The tenside efficiency was not influenced by varied suppository masses (gelatine or Rosupol U, respectively), or by the pH value of the suppositories. Different particle sizes (less than 40 microns or greater than or equal to 40 up to less than 400 microns) of 1 did not change the absorption rate (AUC0-5h) significantly, but did change the plasma concentration-time profile considerably.

Animals↗
PubMed1992

MRI of aggressive meningiomas.

The authors have attempted to establish by MRI morphological criteria for the so-called "aggressive" intracranial meningiomas. The MRI features of 20 meningiomas histologically aggressive (numerous mitoses and small necrotic foci) or malignant (same plus invasion of the subjacent brain tissue) were compared with those of a control population of 26 patients with benign meningioma. The site of the tumour and its histological type had little predictive value, but there was a remarkably high proportion of male patients in the group with aggressive meningioma (9/20 versus 2/26). More than other varieties, aggressive meningiomas frequently emitted, on both T1- and T2-weighted sequences, a heterogeneous signal due to a necrotic focus (P less than 0.01). The high-intensity signal observed on T2-weighted sequences (11/20) was suggestive of syncitial or angioblastic meningioma. Cystic meningiomas were present in virtually equal proportions (3/20 versus 3/26) in the two populations and could raise problems concerning the diagnosis of nature, especially when intraventricular. Gadolinium injection provided further evidence of aggressiveness, such as irregular tumour outline or even contrast enhancement of brain tissue in malignant cases (3/4), but enhancement of the dura mater was equally frequent in both groups (P greater than 0.2). Massive peritumoral oedema was significantly more frequent in aggressive melanomas (P less than 0.01).

Adolescent↗
PubMed1978

[Active therapeutic exercises in combination with vasoactive drug in intermittent claudication (author's transl)].

Earlier investigations have shown that the success of physiotherapeutic exercises in peripheral arterial circulatory disturbances in stage II (Fontaine) can be increased by additional administration of "vasoactive" substances. In the present double-blind study, therefore, 102 outpatients were treated with magnesium nicotinate-magnesium dehydrocholate or a placebo in addition to basic physical therapy. The drug collective (n = 50) showed an increase in walking distance of 24.1% compared with the placebo group (n = 52). Also, in respect to the success rate, the drug collective did better, which, however, may have been due to the unequal distribution of the prognosis factors. Yet it may be concluded that the physiotherapeutic exercises can be effectively supported by the drug tested.

Aged↗
PubMed1978

[Estimation of pharmacokinetic constants in irregular repeated drug administration (author's transl)].

Least squares estimations for the fraction of the dose absorbed, volume of distribution, absorption and elimination rate based on drug measurements in blood and urine after aperiodical administration are described for a one-compartment model with first-order absorption. The non-linear regression analysis is carried out by means of a modified Gauss-Newton iteration procedure by Hartley. BASIC and FORTRAN functions are developed and applied in an example. The advantages of unbiased and consistent least-squares estimations in pharmacokinetics are pointed out.

Kinetics↗
PubMed1977

[Important prognostic factors for the results of physiotherapeutic exercises in intermittent claudication (author's transl)].

In 240 patients with peripheral circulatory disorders (Fontaine Stage II) who had participated in intensive physiotherapeutic interval training daily for 6 weeks between October 1974 and July 1976, it was established that the therapeutic results were not related to age or sex. The "risk" factors of smoking, diabetes mellitus, hypertriglyceridemia, hypercholesterolemia and hyperuricemia individually show no connection with the results. Only overweight, hypertension and coronary heart disease appear to have an unfavorable influence. It is distinctly recognizable that the more risk factors there are combined in a patient with intermittent claudication, the less chance he has of success in physiotherapeutic vessel training.

Aged↗
PubMed1977

[Success of physiotherapeutic interval training combined with standardized hemoderivative in intermittent claudication (author's transl)].

In a cross-over trial with 114 patients, intravenous Actovegin or an oral placebo were administered in addition to basic physiotherapy. In the evaluation 105 of the subjects were taken into consideration. It was shown that the test group (n = 53) achieved a 12% increase in walking distance (measured in the standardized walking distance test) compared with the placebo group (n = 52). The therapeutic success rate, i.e. the evaluation base for the efficacy of basic physiotherapy was comparatively good and statistically confirmed at 69.8% and 73.1% for the two groups. From this it may be concluded that basic physiotherapy can be effectively supported by Actovegin.

Actihaemyl↗
PubMed1977

Some ultrastructural and functional aspects of the golgi àpparatus of Thelohania sp. (Microsporida) in the shrimp Pandalus jordani Rathbun.

Electron microscope observations on Thelohania sp. in the shrimp Pandalus jordani support the view that the Golgi complex in Microsporida is a "classical" one, composed of vesicular, vacuolar, and cisternal components. During development of the sporoblast, a portion of the Golgi complex is seen as an electron-dense reticulum enmeshing the core of the polar filament. Associated with the reticulum are electron-dense bodies. The reticulum and "dense bodies," reported in several previous publications, have not been well understood and have been given a variety of names. The evidence favors the view that these structures have secretory activity in which the reticulum concentrates or synthesized material, some of which takes the form of membrane-bounded granules. It is suggested that the most appropriate name for the reticulum is "reticulum golgien," and the the correct name for the "dense bodies" is the standard cytologic term, "secretion granules." The secretion granules apparently remain in the posterior part of the spore, and may be stored there for some as yet undetermined use.

Animals↗
PubMed1977

[The alcohol effect on the latency time of acoustically evoked potentials (author's transl)].

The alcohol effect on the latency time of acoustically evoked potentials (ERA and 7 ms-Potentials) was investigated in 19 normal hearing persons. The latency time for N1 of the slow evoked potentials was significantly longer by alcohol concentrations of more than 1%. By blood levels=1.5% and by low stimulus intensity the results were more distinct. The alcohol effect was not registered by the brainstem potentials.

Acoustic Stimulation↗
PubMed1977

[Big particle biopsy. An aid in the differential diagnosis of gastric lymphomas (author's transl)].

A definite clinical, radiological, endoscopic or bioptic diagnosis of gastric lymphosarcoma cannot usually be achieved. An attempt to establish the diagnosis should be made, firstly, because of the better prognosis compared to gastric carcinoma, and secondly, because of the alternative therapy available. In the case described the correct diagnosis could be established only by the big particle technique, but not by the conventional forceps biopsy method. The procedure is easy to be done and almost free of complications and is to be recommended whenever an endoscopic suspicion of gastric lymphosarcoma exists.

Aged↗