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Biomedical subjects

B Schulze

Publications and source records attributed to B Schulze.

At least 55 records · Page 3Linked to original sources
PubMed1993

Structural and functional differences between histone H1 sequence variants with differential intranuclear distribution.

The chromatin of most cell types contains several different sequence variants of histone H1. The functional role of this heterogeneity is not known. In the larval tissues of the midge, Chironomus thummi, there are H1 variants of two types. H1 II-1, H1 II-2, and H1 III-1 have similar amino acid sequences and appear uniformly distributed in polytene interphase chromosomes. The total number of gene copies per genome for this type of H1 histones is about 40 in C. th. thummi and 50-60 in C. th. piger. In contrast, histone H1 I-1 is encoded by a single copy gene in C. th. thummi and by two to four genes in C. th. piger. It has a divergent structure and is found only in a limited number of condensed chromosome sites. The N-terminal domain of H1 I-1 contains an insertion that is lacking in the other H1 variants and that is part of a variant-specific bipartite sequence Lys-Ala-Pro-Lys-Ala-Pro-Xaa10-Lys-Val-Ala in front of the conserved central domain. N-terminal peptides of H1 I-1 including this motif, in contrast to the homologous peptide from H1 II-1, competed with the drug Hoechst 33258 for binding to the minor groove of the DNA double helix. Repeats of the sequence Lys-Ala-Pro are also present at the same distance from the conserved central domain, in a single H1 variant of a nematode and of a green alga. The motif could interact with linker DNA in intranuclear targeting or packaging a condensed subtype of chromatin, or both.

Amino Acid Sequence↗
PubMed1993

On-line immunoanalysis for bioprocess control.

Immunoanalytical techniques such as ELISA are often used for the detection of proteins produced in cultivation processes. Owing to the difficulty of automating of the time-consuming traditional ELISA, there is an intense demand for a suitable on-line monitoring method. Combining well-known immunoassays with the FIA technique, we present the heterogeneous and the turbidimetric immuno-FIA methods. The following proteins were investigated with these FIA methods: thermostable pullulanase, IgG, antithrombin III, and recombinant tissue-type plasminogen activator. In the cases of pullulanase and monoclonal mouse IgG, the turbidimetric immuno-FIA was used for on-line analysis of the cultivation process. Results are presented here to demonstrate the effectiveness and application of these immunoanalysis.

Antithrombin III↗
PubMed1993

[Sleep-related respiratory disorders: early detection and follow-up by close patient contact].

Sleep apnoea (SA) ist a challenge to clinical research, since it occurs in up to 10% of the male professionally active population. It is indeed a challenge in respect of diagnosis, clinical aspects and therapy. SA is not only responsible for mental handicaps during daytime caused by disturbed sleep (increased tendency to doze or fall asleep, proneness to accidents), it will also enhance morbidity and mortality in aspect of cardiopulmonary and cardiovascular diseases (hypertension, cardiac insufficiency, disturbances of cardiac rhythm). All kinds of secondary and/or subsequent damage are reversible, provided diagnosis and rigidly introduced and maintained treatment have been performed well in time. SA can be diagnosed, treated and followed up by means of methods that can be flexibly employed outside the hospital, i.e. on an outpatient basis, such as questionnaires, MESAM IV, behavioural counselling, drug therapy). Within the framework of the current three-year project a stepwise concept was developed for diagnosis and treatment that also includes outpatient examination procedures. This system integrates anamnesis, outpatient monitoring, sleep laboratory, therapy and therapy control into a comprehensive feedback system of patient care. The following standardised procedural steps are included in the outpatient part of this system: baseline examination, treatment that can be performed on an outpatient basis, short-term, medium-term and long-term therapy follow-up. If these steps do not yield satisfactory results or if there is a high acute risk, the patient is subjected to in-patient treatment. At present, 683 first examinations and 420 follow-ups have been recorded.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Extrapyramidal features in advanced Down's syndrome: clinical evaluation and family history.

Extrapyramidal, frontal release, and other neurological signs were studied in 54 demented and non-demented patients with Down's syndrome (DS). Fourteen patients were demented and five showed extrapyramidal signs, mainly of the rigid-hypokinetic spectrum and similar to Parkinsonian features in advanced Alzheimer's disease (AD). None of the non-demented patients had Parkinsonian signs. The mean age of the demented DS patients with extrapyramidal signs was significantly higher than that of the patients without. Frontal release signs were present in demented and non-demented patients. A questionnaire showed no increase in either the proportion of early- or senile-onset dementia or Parkinsonism among first- and second-degree relatives of DS patients. Parkinsonian signs appear to be present at a lower frequency in DS than in advanced AD. A speculative hypothesis about a gene dosage effect of Cu/Zn-superoxide dismutase in preventing toxic radical formation in the substantia nigra of DS patients is presented.

Adolescent↗
PubMed1990

Paracentric inversion 14.

A new familial case of paracentric inversion of chromosome 14 inv(14)(q24.1q32.1) ascertained by multiple abortions in a female carrier is presented. A review of the literature revealed 14 cases of paracentric inversion 14 recorded so far. According to the different breakpoints, two major groups of inversions of the long arm of chromosome 14 can be recognized.

Abortion, Habitual↗
PubMed1990

[Street traffic noise and stress experience].

Interpreting a sociological study in the city of Erfurt the results of a written interrogation of noise annoyance of a representative random sample of inhabitants are shown and selected characteristics both of the annoyed and the nonannoyed inhabitants are compared. From noise level measurements a proposal for a traffic noise threshold limit has been derived that corresponds to the requirement for calm. Moreover, moderators have been investigated which interfere with the degree of annoyance; health complaints of both groups of the interrogated individuals were compared. It could be shown, that a written interrogation of inhabitants of a territory is able to deliver sufficiently exact information concerning noise annoyance.

Germany, East↗
PubMed1990

[New aspects of the traffic noise problem in the inner city area].

As a result of a sociological-oriented noise study in the city of Erfurt specific intracity noise problems are analysed via their effects. The authors deal with the expectation of calm of people living in different areas of the city, with the relevance of effect of the two usual evaluation levels Leq and Lmax for noise by running traffic, with noise decrease by sound attenuation improvements, and with the subjective and objective evaluation of an industrial front ventilation element. Moreover, the effects of traffic noise on inhabitants before and after significant traffic reduction are shown.

Automobiles↗
PubMed1990

[Some public health effects of agricultural methane gas plants on the environment].

Several big agricultural fermentation plants for producing of "biogas" are in operation in the GDR. Problems of distances to other objects, utilisation of methane and storage of liquid manure (slurry) are discussed. Some results of experiments about the immissions in the environment are demonstrated. They have point out, that the emissions of microorganisms and viruses cannot be demonstrated in a distance of more than about 200 meters. It is the most important hygienic acknowledge, that the distance of organoleptic observation is always greater than the epidemiologic or sanitary one. Therefore the production of energy by anaerobic fermentation of liquid manure and sewage sludge seems to be an useful way from hygienic point of view.

Agriculture↗
PubMed1990

[Distribution studies of alpha-L-arabinofuranosidase already unstable at pH 7.0 (37 degrees C) in tumor-bearing mice in connection with its possible use to enhance the selectivity of the chemotherapy of malignant tumors].

Graffi et al. (1-3) had proposed the use of exogenous enzymes to toxify inactive transport forms of cancerostatic substances. For this purpose, the pH difference between normal tissues and the tumor was to be exploited, which can be essentially increased by the application of glucose and inorganic phosphate (5-7). Earlier studies using alpha-L-arabinofuranosidase obtained from Aspergillus niger have shown that the selectivity of tumor chemotherapy can be increased in this way (4). The alpha-L-arabinofuranosidases known to date are stabile in a wide pH range (9). However, in some moulds we found pH-labile enzymes of this kind that become irreversibly inactivated in the weakly alkaline or neutral pH range (10, 11). Studies on the distribution of the activity of a pH-labile alpha-L-arabinofuranosidase from Glomerella myabana in tumor-bearing mice have shown that this enzyme is rapidly eliminated from the organism, in contrast to the pH-stable alpha-L-arabinofuranosidase from A. niger. Apart from its excretion via kidney and liver, of importance is the inactivation of the enzyme in the normal tissues. The additional application of glucose strongly increased the activity of this enzyme both in the tumor and in normal tissues (12). By injecting alkaline solutions, stronger inactivation in normal tissues than in the tumor was achieved (13). In the present paper, distribution of an alpha-L-arabinofuranosidase from Fusarium species I 50 (11), inactive already at pH 7.0 (37 degrees C), was studied in tumor-bearing mice. The activity of this enzyme could be enriched under various conditions in the tumor, and especially favorable proved to be the additional application of a combination of glucose and inorganic phosphate. Under these conditions, a higher activity than in the tumor was demonstrable only in the kidney, which can possibly be eliminated in larger experimental animals by diuretics or an appropriate alkaline administration. The investigations have shown that the pH-labile alpha-L-arabinofuranosidases, especially those of Fusarium sp., due to their pharmacokinetic behavior are better suited for use in our therapy concept than the hitherto employed enzyme from A. niger. More recently, Tietze (16) has proposed a similar therapy concept, in which also the glucose-increased pH difference between tumor and normal tissue using tumor-own enzymes, exogenous enzymes as well as transport forms of cancerostatic agents spontaneously hydrolysing under weakly acidic pH conditions is to be exploited.

Animals↗
PubMed1989

DNA haplotypes and frameworks linked to the beta-globin locus in an Austro-Asiatic population with a high prevalence of hemoglobin E.

DNA haplotypes (HT) and frameworks (FW) linked to the beta-globin locus were determined by restriction fragment analysis using eight restriction enzymes on chromosomes bearing the Hb A gene (HBB*A) or the HbE gene (HBB*E) in the So, an Austro-Asiatic population of northeast Thailand with an HBB*E frequency near 0.5. All HBB*E genes were present with FW2, and only two haplotypes were observed (25 HT 27-2, -+- +-; 10 HT 41-2, +----++-). In a control group from the general population of Northeast Thailand the HT distribution was more diverse, and 2 of 20 HBB*E genes were present in FW 3. High frequencies of HBB*E in FW 3 in Southeast Asia are apparently limited to the Khmer population of Cambodia. There were no differences in the hematologic parameters in subjects homozygous for HBB*E/FW2 or HBB*E/FW3.

DNA↗
PubMed1989

Comparative assays of the chemotoxicity of iodinated radiographic contrast media based on impairment of fibrin antithrombin activity.

Radiographic iodized contrast media impair the antithrombin effect of the fibrin clot. The extent of the impairment correlates with dosage and lipophilicity. Normally, 90% of the thrombin activity of 2.3 IU/ml are inactivated by a fibrin clot generated by 2 mg/ml fibrinogen. The effect is due to contrast media-induced protein denaturation with subsequent impairment of thrombin binding to the fibrin clot. Two hepatogenic, two ionic, nephrotopic, and four nonionic contrast media were assayed by this test system at different concentrations. Clear-cut differences were found between the three main groups. Smaller, yet statistically significant, differences could be established between ioglicate and diatrizoate and between iosimide, iopromide or iohexol and iotrolan. No differences were found between iotroxate and iodoxamate. The results are in concordance with the partition coefficients (water/n-butanol) of these contrast media. The assay sensitivity is suitable as a screening system of the chemotoxicity of contrast media. It is easily performed, inexpensive, and assays the clinically important contrast media interaction with fibrinogen.

Blood Coagulation↗
PubMed1989

[Pharmacokinetic studies of the activity of a pH-labile alpha-L-arabinofuranosidase following i.v. injection into tumor-bearing mice].

In order to increase the selectivity of tumor chemotherapy, Graffi et al. have proposed the application of xenogenic enzymes, which are able to split transport forms of carcinostatics under the pH-conditions in the tumor more vigorously than in the normal tissues. This paper describes the distribution within the body and elimination of the activity of the pH-labile alpha-L-arabinofuranosidase from G. myabena compared with the pH-stable enzyme from A. niger, using tumor bearing mice. In vitro, the pH labile arabinosidase was irreversibly inactivated within a few minutes at pH 7.4 and 37 degrees C; however at pH 6.5 it remained active even after several hours. After injection, this enzyme activity was eliminated from the organism by excretion and inactivation within a few hours. Hereby a relatively favourable distribution of the enzyme activity for therapeutic application was reached after 60 minutes. At this time higher activity than in the tumor was measured only in the kidney. The application of glucose led to a strong increase of the enzyme activity in both tumor and normal tissues. This effect was also seen in tumor free mice. In further experiments it will be tried to find out conditions which reduce the glucose induced acidosis. The activity and distribution of the pH-stabile enzyme from A. niger were not influenced by glucose application.

Animals↗
PubMed1989

[Experiments on the modification of the distribution of the activity of various alpha-L-arabinofuranosidases following i.v. application in tumor-bearing mice].

Graffi et al. have proposed the use of exogenous enzymes for selective cleavage of inactive transport forms of cancerostatic substances in tumor tissue. Enzymes appropriate for this purpose should, if possible, show also a certain enrichment in the tumor tissue. In studies on the pH-labile alpha-L-arabinofuranosidase from G. myabena in tumor-bearing mice, under defined conditions in the tumors there could be demonstrated a higher concentration of the active form of the enzyme than in most of the normal tissues. However, the enzyme activity is eliminated from the organism in a relatively short time through excretion and inactivation. The application of glucose led to a strong increase of activity of the enzyme injected, both in the tumors and in the normal tissues. It has been shown in the present investigations that this increase in the enzyme activity can be curtailed more strongly in normal tissue by alkali application than in the tumors. In this way, a distribution of the enzyme activity favorable for therapy experiments is obtained. Only in the kidney and urine has a higher activity of the applied enzyme been measured than in the tumors. In the second part of this work it has been attempted to achieve accumulation of activity of the pH-stable alpha-L-arabinofuranosidase from A. niger through application of angiotensin, but no positive results have been reached under the various experimental conditions used.

Alkalies↗
PubMed1989

Temperature dependent pH-instability of some alpha-L-arabinofuranosidases.

In this paper are described alpha-L-arabinofuranosidases, partially purified from some moulds, with very high lability of their activity to weakly alkaline or neutral pH-values. This pH-lability strongly depends on temperature. The form of the inactivation curves suggests involvement of charge changes in this irreversible process. These enzymes may be useful for optimization of the tumor therapy concept described by Graffi (5).

Ascomycota↗
PubMed1988

Cardiac defects in chromosomally abnormal human embryos of 10-14 weeks' gestation.

Cardiac defects were studied in five chromosomally abnormal embryos of 10-14 weeks' gestation by free-hand microdissection of hearts measuring 2.5-6 mm in diameter. The type of cardiac malformation alone or in association with other anomalies helped to confirm the chromosome diagnosis established prenatally by chorionic villus sampling or after spontaneous abortion. It was suggestive of a chromosomal disorder in one case in which cytogenetic investigation had failed.

Adult↗
PubMed1988

Analysis of human exocrine pancreatic proteins by means of pore gradient polyacrylamide gel electrophoresis.

Pancreatic juice collected by endoscopic retrograde cannulation of the pancreatic duct after administration of secretin and pancreozymin was analyzed by pore gradient polyacrylamide gel electrophoresis. Two electrophoretic systems, an alkaline (pH 8.9) and an acidic (pH 5.0), were elaborated to obtain optimal separation of exocrine proteins. 13 bands under alkaline conditions and 17 bands by running in the acidic system were separated and distinguished by Coomassie-Brilliant Blue G 250 staining. Fourteen proteins were identified using enzymatic and immunological methods: one form of each of lipase, chymotrypsinogen, prophospholipase A2, procarboxypeptidase A and trypsin inhibitor, two forms of each of procarboxypeptidase B and proelastase, three forms of each of trypsinogen and amylase. An additional band was identified as albumin.

Adult↗