Biomedical subjects

B Fuchs

Publications and source records attributed to B Fuchs.

At least 19 recordsLinked to original sources

PubMed1995

Phosphorylation studies on rat p53 using the baculovirus expression system. Manipulation of the phosphorylation state with okadaic acid and influence on DNA binding.

To elucidate the role of phosphorylation of p53 we used the baculovirus expression system to obtain high yields of protein eventually in distinct phosphorylation states. Initially, we obtained only marginal phosphorylation, despite high levels of expression. Two-dimensional phosphopeptide maps exhibited the same pattern as known from rat cells although some sites were underrepresented. Coexpression of simian virus 40 (SV40) large T antigen or cyclin-dependent kinases, cdc2 or cdk2, had only marginal effects on the phosphorylation state of p53. However, when we employed the phosphatase inhibitor okadaic acid, overall phosphorylation of p53 was drastically enhanced in a dose-dependent manner and resembled that of p53 from SV40-transformed rat cells. This hyperphosphorylation resulted in enhanced binding of a consensus oligonucleotide as revealed by electrophoretic mobility shift assays. To assess the role of individual phosphorylation sites, we generated a set of mutants at putative or identified sites. All mutants retained the ability to bind wild-type conformation-specific antibody Pab1620, to complex with SV40 large T antigen, and to bind to the consensus oligonucleotide. Moreover, most mutants exhibited enhanced DNA binding upon okadaic acid treatment, except for a mutant at the cdk site which failed to do so. These data show that: (a) insect cells contain all the protein kinases necessary for phosphorylation of a mammalian protein, p53; (b) in insect cells the ratio of kinase/phosphatase activities differs from that in mammalian cells so that underphosphorylation of recombinant proteins in this system may result from high phosphatase activities rather than saturation of kinases with recombinant substrate; (c) the system can be manipulated to obtain subpopulations of recombinant protein in a desired phosphorylation state, and (d) phosphorylation may regulate the DNA-binding activity of p53.

Amino Acid Sequence↗

PubMed1995

p53 phosphorylation mutants retain transcription activity.

To investigate the effect of phosphorylation on the transcription activity of p53, ten phosphorylation mutants were constructed covering all the identified phosphorylation sites of rat p53. These included mutants of two casein kinase I sites (Ser6 and Ser9), two DNA-PK sites (Ser15 and Ser39), a p34cdc2 site (Ser313), the adjacent Ser312 and a casein kinase II site (Ser390). Two double phosphorylation mutants (Ser4, 6 and Ser15, 390) and one triple phosphorylation mutant (Ser4, 6 and 15) were also constructed. The transcription activity of all the p53 phosphorylation mutants was tested by transfection into two different types of cells, Saos-2 cells and p53(-/-) fibroblasts derived from p53 knock out mice, which both lack endogenouse p53. Surprisingly, all the p53 phosphorylation mutants retain transcription activity and the seven mutants tested can also suppress cell growth.

Animals↗

PubMed1995

The effect of feeding piglets up to the 100th day of their life with peat preparation on their growth and physiological and biochemical indices.

The experiment was carried out on a group of 300 piglets. During experiment the effect of supplementation with peat preparation coming from different charges on productivity, selected productive and biochemical indices was examined. All these indices were compared with a negative and positive control. A positive effect of supplementation with peat preparation in amount of 300 mg/kg of mixture on body weight increase and physiological and biochemical indices was found. The examined peat preparation coming from different charges demonstrated different effect which shows that it was not an entirely homogeneous material.

Aging↗

PubMed1994

[Experiences with internal fixation of isolated fractures of the head of the radius].

The advantages of internal fixation of fractures, with the possibility of immediate resumption of the function of the fractured bone, are in contrast to the well-known complications described in the literature. These complications and our own unsatisfactory results after surgical treatment of fractures of the head of the radius induced us to carry out a randomized prospective study of primary functional treatment of such fractures without external or internal stabilization. From December 1991 through December 1992, a total of 70 patients were treated according to a strict treatment protocol at the Graz Hospital for Accident Surgery, and CT was used for observation of the healing process. The positive early results, which in 91% of all cases were classified as very good or good, the lack of complications that sometimes follow surgical treatment, the markedly earlier recovery of the patient's working capacity, and the clearly shorter--albeit somewhat more expensive--treatment period required have led us to continue using this method at our hospital and also to recommend its use elsewhere.

Adult↗

PubMed1993

The thymus-independent antigen alpha(1-3) dextran elicits proliferation of precursors for specific IgM antibody-producing cells (memory cells), which are revealed by LPS stimulation in soft agar cultures and detected by immunoblot.

Single antibody-forming cells (AFC) specific for alpha(1-3) dextran (Dex) from i.p.-immunized BALB/c mice were enumerated in soft agar cultures by blotting on antigen-precoated membranes and subsequent staining via enzyme-coupled anti-IgM antibodies. Short cultures (2 h) revealed AFC as harvested ex vivo, while in long-term cultures (4 days), in the presence of lipopolysaccharide (LPS) as B cell mitogen, cells or colonies developed by differentiation in vitro. Whereas the spleen contained most AFC ex vivo in a sharp-peak response at 4 and 5 days after i.p. injection of Dex in aqueous solution, peritoneal exudate cells (PEC) contained only very few AFC. However, the same PEC population developed Dex-specific cells or colonies after 4 days of culture. The isotype of antibodies was IgM. The frequency of these Dex-specific LPS-inducible precursor cells rose exponentially in the course of the immune response to a broad plateau and was still, 11 weeks after Dex injection, approximately 40-fold higher than in non-immunized mice. Since these cells increased in frequency after antigen injection, and since they could not be detected as AFC during 2 h ex vivo, they were regarded as memory cells. They seemed to be arrested in vivo, but could be induced to differentiation and/or proliferation in vitro. Although these cells had the functional characteristics of memory cells as defined above, they produced anti-Dex antibodies of IgM isotype. Their population might be critical for the protection of the peritoneal cavity against microbial invasion from the intestines, and it may be significant in this context that we could evoke a peritoneal memory cell response only when antigen was injected intraperitoneally, but not intravenously. In athymic BALB/c-nu/nu mice only few of these Dex-specific memory cells were found. It is possible that T cells exert a regulatory influence on this pathway of differentiation.

Animals↗

PubMed1993

Techniques for endoscopic and non-endoscopic intracorporeal laser applications.

This article deals with various designs of CO2 and Nd:YAG lasers currently used in surgery. It is discussed how their wavelength and beampath characteristics can be utilized in either the contact or the non-contact method to achieve specific clinical aims. These may concern endoscopic procedures, e.g. palliative tumour destruction or haemangioma or cystic membrane coagulation, or non-endoscopic procedures, as exemplified by two case reports on treatment for a congenital vascular disorder and varicosis, respectively. As there is a certain overlap of laser and high-frequency applications, their respective advantages and drawbacks are compared in detail. The main safety concern in HF surgery is that of errant currents in the patient, whereas in laser applications the main hazard is to the operators' eyes. This hazard can be safely eliminated.

Adult↗

PubMed1993

Lasers.

Explore the source record for details and available documents.

Laser Therapy↗

PubMed1993

The effect of carotene and vitamins A and E supplementation on reproduction of sows.

The effects of synthetic and natural beta-carotene as well as vitamins A and E supplementation on the fertility of sows and number of piglets in a litter were the subject of our studies. The sows fed beta-carotene had from 2 to 4 more piglets in a litter. Vitamin E had a harmful influence on beta-carotene action. It was found that synthetic beta-carotene and vitamin A increased the number of viable embryos and yellow bodies in the sows slaughtered on the 28th day of gestation, moreover beta-carotene subsequently improved the fertility of sows in the next reproductive cycle.

Animal Feed↗

PubMed1993

[Use of laser in vascular surgery].

The use of lasers in the field of vascular surgery concerns 3 completely different principles of application. The main field is the therapy of hemangiomas and congenital vascular diseases (CVD). The experience of the therapy of congenital diseases can be also used in the treatment of varicosis, especially in the treatment of the perforating veins. In contrast to the angioplasty, where the therapeutic aim is recanalisation of an arterial vessel, in the venous system it is the occlusion of a vessel. The thermal procedures using argon- or Nd:YAG lasers with hot tips, saphire tips or with the bare fiber are no longer relevant. Only photoablation using pulsed lasers is able to remove calcified material. The excimer laser is currently the best known system for angioplasty. New developments, for example solid state lasers like the holmium laser, have as yet to show their advantages. A main emphasis of research should be the improvement of catheter systems since present applications are limited by those currently available catheter systems. Tissue fusion is still an experimental procedure. There is a lot of basic research to be done to establish this procedure in the clinical routine.

Angioplasty, Laser↗

PubMed1991

p-glycoprotein expression in malignant melanoma.

In some human malignancies resistance to chemotherapy is caused by an energy-dependent efflux system, responsible for the removal of chemotherapeutics out of the resistant tumor cells. A major component of this efflux system is the permeability glycoprotein (p-glycoprotein), which depends on the multidrug-resistance gene MDR1. We have tested p-glycoprotein in primary and metastatic human melanoma by use of the monoclonal antibody C219; a substantial expression was only observed in 1/37 primary melanomas and in 1/27 melanoma metastases. None of the patients with negative metastases responded to chemotherapy. Moreover a complete remission of metastatic growth was observed in the patient with the metastasis significantly expressing the p-glycoprotein. Sequential studies revealed no significant increase of p-glycoprotein-positive cells during and after chemotherapy. We conclude that drug resistance in human melanoma does not usually depend on the p-glycoprotein-related efflux system. Other mechanisms are obviously responsible for drug resistance in this human malignancy.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1991

The relationship between characteristics of the tumor cells and sex of the patients in primary malignant melanomas.

Sex is a well proven prognosticator in primary malignant melanoma. We studied 19 parameters of tumor cells in primary malignant melanoma from 391 patients, the purpose being to determine if melanomas in men and women are alike. Apart from results in thin melanomas, no difference was seen between the sex groups. Thin melanomas showed a significant difference for the melanoma-associated antigen G7-E2 (higher expression in women) and the histocompatibility antigen HLA-DR (higher expression in men). The results suggest that sex-related prognostic differences are due more to host than to tumor characteristics.

Antigens, Neoplasm↗

PubMed1991

[Therapy of hyperammonemia in carbamyl phosphate synthase deficiency with peritoneal dialysis and venovenous hemofiltration].

Inborn errors of metabolism with hyperammonaemia cause emergency situations with unconsciousness, convulsion, hyperpnoea and hyperpyrexia. Therefore hyperammonaemia has to be treated immediately after diagnosis to avoid irreversible damage. Two newborns with carbamylphosphates synthetase deficiency are described. Both, continuous peritoneal dialysis and venovenous haemofiltration have proved to be effective methods to reduce serum ammonia concentration to values of less than 300 mu/l. Because of the severity of the enzyme defect in both cases, (carbamylphosphate synthetase was not detectable in liver tissue), treatment finally had to be stopped, and both patients died.

Amino Acid Metabolism, Inborn Errors↗

PubMed1990

[Bronchogenic carcinoma in women].

A total of 440 women with morphologically tested primary bronchogenic carcinoma were hospitalized in 1961-1987. The patients' average age was 57 years, 22% persons were under 50 years. In 32% women carcinoma was found accidentally in the asymptomatic stage of the illness, 4% women had subjective complaints which they considered insignificant, however, subjective complaints in 64% patients helped to diagnose it. The most frequent complaints were temperature, breathlessness, chest pain and loss of weight. In 2% women, the first sign was hemoptysis found most frequently as an isolated symptom. The history of 9.5% patients showed pulmonary TB, in 27% women bronchogenic carcinoma was first regarded as pulmonary TB and treated with anti-tuberculotics. The family history of 32% patients showed malignant diseases, most frequently gastric carcinoma, while bronchogenic carcinoma was found in 5.7%, of family members. The group consisted of 46% smokers and 54% non-smokers. The women smokers had smoked for 29 years on average, had smoked 205 thousand cigarettes on average, the average daily amount was 20 cigarettes. Regardless of their smoking habits, the most frequent histological type was found to be adenocarcinoma in 47% cases, with the squamous-cell type prevailing in the smokers (37%), and adenocarcinoma in non-smokers (59%). 36% of the patients underwent surgery, the most frequent contraindication for surgery were generalization of the process and lymph node metastases. Lobectomy was the most common operation performed (62%). 5 patients died within the first post-operative month.

Adult↗

PubMed1990

[The prevalence of bronchial asthma in a selected sample of the adult Prague population].

The authors assessed the prevalence of bronchial asthma in 8458 18-year-old and older inhabitants of an economic area in Prague 8. The population of the area up to December 31, 1987 was 90,458 adults. The health communities were selected in a random way to comprise the central as well as peripheral parts of Prague 8. By means of questionnaires information was assembled from 70.9% of the respondents and after supplementation of data by various doctors the scope of information was 89.9% (7605/8458). For detailed examination 902 subjects were selected with "confirmed" and suspect symptoms of asthma. The anamnestic data were analyzed and pulmonary ventilation was examined (flow-volume), and depending on indication, also the provocation or bronchodilatation inhalation test, skin tests, and total IgE. The cumulative prevalence of bronchial asthma was 2.3% +/- 0.3% (174/7605). The highest prevalence values were in subjects under 20 years--3.5% and under 30 years--3.6%. The contemporary prevalence was 2.0% +/- 0.3% (152/7605). Nonatopic asthma was recorded in 54%, atopic asthma in 46% of the subjects.

Adolescent↗

PubMed1990

Assessment of insulin needs in insulin-dependent diabetics and healthy volunteers under fasting conditions.

It is known from clinical observations, theoretical investigations as well as from data patients with intensified insulin therapy and wearers of insulin pumps that the body also requires insulin under fasting conditions. Therapeutic studies as well as the investigations carried out using the artificial pancreas indicate that just under half of the daily insulin requirement is not meal-related, and the other half is dependent on food. The question arose as to whether there are any differences in the basal insulin requirement depending on the time of day and whether differences can be detected between type I diabetics and healthy reference subjects. The results show that analogous changes occur in the early hours of the morning in type I diabetics and healthy normal subjects: these correspond to the clinical familiar dawn phenomenon. The different courses of blood glucose and insulin requirement as measured on the basis of the release of insulin by the Biostator as well as the insulin secretion profile in healthy normal volunteers under fasting conditions do not show any further differences which depend on the time of day.

Adult↗

PubMed1990

[Vascular tumors of the lungs].

A series of nine vascular tumors of the lungs, five of them being benign hemangiomas, three hemangiosarcomas and one hemangiopericytoma is presented. In five patients the disease was detected on the basis of subjective complaints which indicated necessary hospitalization, in the other four patients the tumours were revealed by chance during preventive X-ray examination or X-ray examination for other causes. These patients were admitted to hospital for progression of lung changes. Five of the patients underwent surgery, lobectomy, was made in two cases, the other patients were treated by segmental, V-shape or atypical lung resection. Patients with benign hemangiomas manifested the best prognosis even in those where surgery was not possible. In cases of hemangiosarcoma or hemangiopericytoma the outlook is exceptionally serious even in primary forms. In the preoperation diagnostics of arteriovenous hemangiomas the tomographic examination and lung angiography represents an important help, in the other vascular tumours it is particularly CT and lung biopsy.

Adult↗

PubMed1989

[Pathogenesis and clinical aspects of Reinke edema. Long-term studies].

Since 1973, 307 patients have been treated for Reinke's oedema in the ENT Department of the University of Marburg. A retrospective study from 1983 and observations up to 1989 investigated the aetiology and the prognosis of the disease. Two aetiological factors were found: smoking and voice abuse. Surgical treatment, stripping of the vocal cords as described by Kleinsasser was successful. There were no recurrences and no malignant degenerations. The prognosis was considered to be good. Two other long-term studies of Reinke's oedema are compared with our findings. Controversial opinions about the therapy are discussed.

Adult↗

PubMed1989

[Benign tumors of the lungs and bronchi].

Results of a retrospective study from the years 1961 to 1986 have been presented based on hospitalization of 292 patients with benign tumours of the lungs and bronchi verified by histology. The prevailing tumours in the cohort were chondrohamartomas (62.0%) and carcinoids (21.9%). The tumours were localized more frequently inside the parenchyma (75.7%) than inside the bronchi (24.3%). The patients were men in 59.9% and women in 40.1%, the mean age during hospitalization being 48.8 years. In 60.6% of the patients the tumours were detected during an accidental radiographic examination, the tumour increased in size over several years of observation in 22.6% of the patients. A total of 280 patients (95.5%) were surgically treated, the tumour was removed in the bronchoscopic way in nine cases, two patients could not be operated on for advanced processes and one patient refused the operation. In 83.2% of the patients the surgical intervention was smaller than lobectomy, larger interventions prevailed in endobronchial localization making 54% on the whole, bronchial carcinoids being 71% of these.

Bronchial Neoplasms↗