PubMed Health⌕ Search

Biomedical subjects

K Günther

Publications and source records attributed to K Günther.

At least 73 records · Page 4Linked to original sources
PubMed1995

[The measurement of the femoral torsion angle in children by NMR tomography compared to CT and ultrasound].

PURPOSE: Anteversion of the femoral neck was measured by MRI in 19 children (37 hips) preoperatively before femoral rotation osteotomies. MATERIAL AND METHODS: The results of this new technique were compared with values for anteversion obtained by CT and ultrasound. The measurements were performed independently by two observers to determine the correlation between the three different methods and to assess their reliability. RESULTS: It was possible to show a high correlation coefficient (Pearson) between MRI and CT (r = 0.77) as well as MRI and sonography (r = 0.81). The mean angles obtained by CT (34 degrees, range +5 to +82 degrees) and ultrasound (25.6 degrees, range +10 to +40 degrees) appeared larger than the MRI values (mean angle 23.2 degrees, range 0 to +65 degrees), which can be explained by the different measurement techniques. Mean inter- and intra-variability was low for MRI (r = 0.97 and r = 0.97) and CT (r = 0.99 and r = 0.96) but slightly higher for sonography (r = 0.88 and r = 0.88). MRI is a new reliable and precise method to evaluate femoral anteversion that does not require ionising radiation. CONCLUSION: MRI is recommended for preoperative planning of paediatric femoral rotation osteotomy patients.

Adolescent↗
PubMed1994

Bioremediation of contaminated groundwater.

Contaminated groundwater from industrial areas in former East Germany was biologically treated using lab-scale solid-state reactors. The ability of bacterial strains of the autochroneous microflora to utilize representative pollutants was tested.

Benzene Derivatives↗
PubMed1994

Characterization of membrane proteins exported from Plasmodium falciparum into the host erythrocyte.

Plasmodium falciparum is an intracellular parasite of the red blood cell. During development it exports proteins which are transported to specific locations within the host erythrocyte. We have begun to identify and characterize exported membrane proteins of P. falciparum in order to obtain specific marker molecules for the study of the mechanisms involved in the distribution of parasite-derived proteins within the host cell. In this report we describe the characterization of a 35 kDa protein which is recognized by a monoclonal antibody. The protein is tightly associated with membranes isolated from infected erythrocytes; it is resistant to extraction with alkali and soluble after treatment with detergents. It is located at the membrane of the parasitophorous vacuole and in membrane-bound compartments which appear in the cytoplasm of the infected erythrocyte. The protein co-localizes with the previously described exported protein-1 (exp-1). Considering its localization and physical similarities to exp-1, we name the 35 kDa protein the exported protein-2 (exp-2).

Animals↗
PubMed1994

[Prevention of para-articular ossifications after endoprosthetic hip joint replacement by postoperative irradiation].

In a prospectively randomized study, 137 patients with 141 hips at high risk for heterotopic ossification (HO) received prophylactic radiation therapy (RT). Patients were randomly assigned to a low-dose regimen of five fractions of 2 Gy each (n = 73) or a high-dose regimen of either 10 fractions of 2 Gy each (n = 7) or five fractions of 3.5 Gy each (n = 61). Treatment outcome was assessed by comparing immediately postoperative radiographs with radiographs obtained at least 6 months after hip surgery (Brooker grading score). Positive responses (ie, effective prophylaxis of HO) were seen in 129 (91.5%) hips. Treatment failures were observed in 12 (8.5%). Use of a nonsteroidal antiinflammatory drug (NSAID) lowered the failure rate in both groups. High RT dose with a short duration (< or = 9 days) and use of an NSAID was significantly (p = 0.009) correlated with treatment success. RT delivered within a few days after hip surgery is effective in preventing HO, even in high-risk patients, and provides an alternative of at least equal value for patients with contraindications to long-term medication with either NSAIDs or corticosteroids.

Adult↗
PubMed1994

Weight reduction after gastric bypass and horizontal gastroplasty for morbid obesity. Results after 10 years.

OBJECTIVE: To evaluate the long term value of gastric bypass and horizontal gastroplasty for the treatment of morbid obesity. DESIGN: Retrospective study. SETTING: University hospital. SUBJECTS: 119 patients of 195 who were operated on between 1976 and 1986. INTERVENTIONS: Horizontal gastroplasty (n = 15), transected gastric bypass (n = 83), or stapled gastric bypass (n = 21). MAIN OUTCOME MEASURES: Weight loss, reduction in body mass index, and morbidity. RESULTS: Mean (SD) body weight (kg) after gastroplasty decreased from 139 (20) to 112 (14) at one year, but had increased to 130 (22) at 10 years. The corresponding figures for transected gastric bypass were 134 (24), 95 (20), and 103 (22); and for stapled gastric bypass 137 (27), 100 (24), and 112 (23). The figures for body mass index showed a similar pattern. Three quarters of the patients developed physical or psychological complications after the operation that were related to either the obesity or the operation, or both. CONCLUSIONS: None of the three operations provided adequate or prolonged control of morbid obesity, and the morbidity was high. Too large a proximal pouch, or disruption of the line of staples, may have been responsible.

Adolescent↗
PubMed1993

A novel short consensus repeat-containing molecule is related to human complement factor H.

We have identified a novel factor H-related cDNA, which was isolated from a human liver cDNA library. The DOWN16 clone is 1269 base pairs in size and hybridized to a mRNA of 1.4 kilobases. Similar to the previously described factor H-related proteins, the predicted translation product of 331 amino acids contains a hydrophobic signal sequence followed by a stretch of five short consensus repeats (SCRs). These five SCRs display homology to SCRs of factor H: SCRs1-3 (DOWN16) are homologous to SCRs6-8 of factor H, while SCRs4 and -5 are related to SCRs19 and -20. In vitro translation demonstrated that the DOWN16 cDNA encodes a primary translation product of an apparent molecular mass of 37,500 Da which is directed to the secretory pathway and is glycosylated. Thus, we propose that the protein will be present in human serum. The relatedness of structural elements between this novel gene and factor H may suggest common functions of these proteins not yet determined.

Amino Acid Sequence↗
PubMed1993

[Determination of minerals and trace elements in selenium tea from the Enschi district, People's Republic of China, and in its infusions using inductively coupled plasma-atomic emission spectrometry, graphite furnace atomic absorption spectrometry and instrumental neutron activation analysis].

The Enschi district in Hubei province, Peoples Republic of China is geochemically one of the two seleniferous regions, producing both selenium (Se) black tea and the Se green tea. Three samples of green tea with different Se contents and one non-Se tea were analysed. The following mineral and trace elements were determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES): K, Ca, Mg, Na, P, S, Al, Mn, Fe, Ba, Sr, Co, Ni, Cu, Zn, Mo, and Cr. Except for Mo, Co, and Cr, all other elements in infusions of the samples analysed were also measured, since their concentrations are lying over their detection limits. The Se content in the tea samples and in the infusions were measured with graphite furnace atomic absorption spectrometry (GFAAS). The accuracy of Se determination was tested by measuring untreated tea samples with instrumental neutron activation analysis (INAA). The Se content in the measured samples was 1 to 8.5 micrograms/g. In addition to Se, 17 other elements were measured in the tea samples and 14 others in the infusions. With this data the extractable part of this elements in the infusion were calculated. Up to 10% of the Se was found in a first infusion.

China↗
PubMed1993

Calcium carbonate (CaCO3): an efficient and safe phosphate binder in haemodialysis patients? A 3-year study.

In an uncontrolled study, 22 dialysis patients (46 +/- 14 years, duration of dialysis 20 +/- 11 months) were treated with CaCO3 over a period of up to 3 years to lower their serum phosphate. The use of 4.5-9 g CaCO3 daily over a period of 9 months led to a reduction of mean serum phosphate from 2.51 to 1.51 mmol/l in 77% of patients, with a simultaneous increase in mean calcium concentration from 2.23 to 2.47 mmol/l, and an improved control of secondary hyperparathyroidism by reduction in mPTH from 1552 to 1032 pg/ml and in APH activity from 6.25 to 4.55 mumol/s/l. In long-term CaCO3 treatment of up to 3 years, however, a constant effective phosphate reduction could not be achieved. There was a progression (77%) of pre-existing microcalcification and a new appearance (42%) of microcalcification in vessels and soft-tissue areas of the hand. The percentage of patients with soft-tissue calcification increased from 43 to 67% during a treatment period of 3 years. We conclude that CaCO3 alone is not suitable on a long-term basis for phosphate reduction in dialysis patients.

Adult↗
PubMed1993

Clinical evaluation of a new dialyzer, FLX-12 GW, with a polyester-polymer alloy membrane.

The performance of a membrane in renal failure therapy is determined by its structure, its overall mass transfer properties, and its blood compatibility. In this regard, removal of beta 2-microglobulin (beta 2M) has become a major objective of dialysis therapy. In the present study, a newly developed high-flux membrane composed of a polyester-polymer alloy (PEPA) with the components of polyarylate and polyethersulfone (dialyzer FLX-12 GW; Nikkiso Co., Japan) has been evaluated with regard to both biocompatibility and elimination capacity for beta 2M during hemodialysis of 8 stable chronic uremic patients. The clearance values of low molecular weight solutes were in the same range as those reported for high-flux dialyzers of comparable surface area. There was no drop in leukocyte counts and only a minimal fall in platelet counts nearly in the same range as has been observed by other investigators using polyamide membrane. C3a Des Arg generation was low, and C5a Des Arg formation was not significantly influenced. There was a sharp drop in the serum beta 2M level (-35%) during dialysis with a clearance between 59.7 +/- 5.6 ml/min (QB 200 ml/min) and 70.1 +/- 9.7 ml/min (QB 300 ml/min), respectively. Accordingly, the sieving coefficient was calculated to be 0.2 at 30 min after start of dialysis and 0.6 1 h later. The membrane was able to remove 184.0 +/- 22.3 mg/4 h due to an apparent rate of adsorption during the first hour of treatment in combination with high transmembrane transfer in the following time.

Adult↗
PubMed1993

[In vitro toxicity tests of bioceramics and bone transplants in fibroblast culture].

Prior to the clinical use of synthetic bone substitutes and allogenic bone transplants, potential toxicity resulting from various different manufacturing, storage, and sterilisation techniques should be excluded. In order to develop a reliable and reproducible in vitro model for the investigation of possible tissue reactions after implantation of biomaterials, we modified an established animal fibroblast culture technique used to test chemical agents for acute unspecific cytotoxicity. Subcultivation of human fibroblasts produces stable monolayer cultures with the aid of which, standardised, accurate and reproducible evaluation of toxic effects, as well as the direct visualisation of fibroblast ingrowth into porous implant material, is possible. Gamma-irradiated synthetic implants and bovine hydroxyapatite failed to show any substantial cytotoxicity. In contrast, ethylene oxide sterilised implant material, as well as fresh untreated trabecular bone showed a significant toxic effect in comparison with cryopreserved and autoclaved trabecular bone.

Animals↗
PubMed1992

The pharmacokinetics of the beta 2-adrenoceptor agonist fenoterol in healthy women.

We have studied the pharmacokinetics of fenoterol in healthy women during and after a 3 h intravenous infusion of different doses within the therapeutic range for tocolysis (0.5 microgram.min-1, 1.0 micrograms.min-1, and 2.0 micrograms.min-1). A specific and sensitive radioimmunoassay was used for the determination of fenoterol. For compartmental analysis the plasma concentration time data were fitted with the TOPFIT program, assuming two exponentials. The total clearance of fenoterol increased with dose (1299 ml.min-1 at 0.5 microgram.min-1, 1483 ml.min-1 at 1.0 micrograms.min-1, and 1924 ml.min-1 at 2.0 micrograms.min-1), as did the apparent volume of distribution (from 49 l at the lowest to 85 l at the highest dose). In contrast, the apparent half-lives were not dose-dependent, with t1/2.lambda 1 4.8 min and t1/2.lambda z 52 min.

Adult↗
PubMed1992

Localisation of hypoxanthine phosphoribosyl transferase in the malaria parasite Plasmodium falciparum.

The enzyme hypoxanthine phosphoribosyl transferase of the human malaria parasite Plasmodium falciparum has been located in parasites and parasite-infected erythrocytes by antibody probing. The probe was a polyclonal rabbit antiserum made against the parasite enzyme made in Escherichia coli. The enzyme is associated with membrane-bound compartments in merozoites and asexual blood parasites. In particular, indirect immunofluorescence studies reveal the enzyme localized in vesicle-like structures within the cytoplasm of the infected erythrocyte. This is the first time a P. falciparum protein of defined metabolic function has been tracked to a site outside the parasite cytosol. Studies on the targeting of the enzyme using a cell-free system suggests that the protein reaches its destination via a route different from the normal secretory pathway.

Amino Acid Sequence↗
PubMed1991

In vitro translation of Plasmodium falciparum aldolase is not initiated at an unusual site.

It has been proposed recently that translation of fructose-1,6-diphosphate aldolase of the malaria parasite Plasmodium falciparum is initiated at a UAG codon, both in the parasite and in a rabbit reticulocyte cell-free translation system. We have introduced mutations around that UAG codon and find that cell-free expression of a construct encoding an AUG in this position results in a slightly larger translation product. The translation product of the construct encoding the UAG codon is of the same apparent molecular weight as the products obtained from two other constructs; one in which the UAG is replaced by AAG, and one in which nucleotides upstream from a second AUG codon are deleted. Thus we show that translation is not initiated at the UAG and conclude that synthesis of aldolase in the parasite starts at an AUG, provided after splicing of pre-mRNA.

Animals↗
PubMed1991

An exported protein of Plasmodium falciparum is synthesized as an integral membrane protein.

Exp-1 is an antigen of Plasmodium falciparum which is transported from the parasite cell to the membrane of the parasitophorous vacuole and to membranous compartments in the erythrocyte. To investigate how this protein is transported, we studied the synthesis and membrane translocation of exp-1 in a cell-free system. The protein was translocated into canine pancreatic microsomes. Its N-terminal half was thus protected from proteinase K digestion, suggesting that exp-1 is an integral membrane protein with its N-terminus facing the lumen of the microsomes. This conclusion has been confirmed in vivo. In parasitized erythrocytes, exp-1 is membrane-associated and resistant to extraction with alkali, as would be expected for an integral membrane protein. Moreover, using segment-specific monoclonal antibodies, we have shown that here again the N-terminus of exp-1 faces the inside of vesicles, inaccessible to proteases, whereas the C-terminus is degraded. We conclude that exp-1 is an integral membrane protein and infer that it is transported by vesicles from the parasite to a compartment in the host cell cytoplasm.

Animals↗