Search PubMed⌕ Search

Biomedical subjects

E Müller

Publications and source records attributed to E Müller.

At least 127 records · Page 7Linked to original sources
PubMed1998

Effect of ischemia on localization of heat shock protein 25 in kidney.

The effects of renal ischemia on the intracellular distribution of the low-molecular weight heat shock protein (HSP)25 were examined using immunofluorescence microscopy. In all kidney zones, ischemia decreased HSP25 in the supernatant of the tissue homogenates and increased it in the pellet fraction (containing mainly nuclei and cytoskeletal components). This was associated with disappearance of HSP25 staining from the brush border of proximal convoluted tubule (PCT) cells. Because no nuclear staining of cortical tubule cells was apparent either in control or ischemic kidneys, ischemia seems to cause a closer association of HSP25 with cytoskeletal components. HSP25 probably participates in the postischemic restructuring of the cytoskeleton of PCT cells.

Animals↗
PubMed1998

Oncogene and suppressor gene expression as a biomarker for ethylene oxide exposure.

Ethylene oxide is a proven genotoxic chemical, and there is lots of evidence suggesting its carcinogenic effects in humans. The unexpected massive appearance of a certain tumorous cluster in personnel exposed to ethylene oxide in a Hungarian county hospital focused attention on the effects of this toxic gas. Since we had developed an animal model for the investigation of alterations in onco/suppressor gene expression due to external carcinogenic agents, and this model had already been used to evaluate the carcinogenic effects of cytostatic drugs in humans, an analysis of the effects of ethylene oxide exposure seemed to offer further information on the usefulness of gene expression as a biomarker. The main purpose of our study was to determine whether or not ethylene oxide exposure causes an elevated expression of onco/suppressor genes in the white blood cells of exposed people. Two different exposed groups and one control group were included in the study. The N-ras and p53 genes were chosen for the investigations of gene expression. N-ras is known to be activated in several tumor types, and p53 is also involved in carcinogenesis and plays an important role in the cellular answer mechanism to exogenous toxic effects. RNA was isolated from the white blood cells, slot blotted onto nitrocellulose membranes, and hybridized with chemoluminescently labeled gene probes. The results were detected on X-ray films and scanned into a computer, and relative risk for elevated gene expression was calculated in each group. Elevated N-ras and detectable p53 expressions were observed more frequently in both exposed groups compared with the control group (relative risks--N-ras: 1.57 [0.77-3.22] and 2.34 [1.21-4.52]; p53: 6.67 [2.35-18.92] and 6.06 [2.10-17.49]).

Biomarkers, Tumor↗
PubMed1998

Comparisons of the ski turn techniques of experienced and intermediate skiers.

We compared selected kinematic variables for four different ski turn techniques performed by five experienced and five intermediate male skiers. The four ski turn techniques were the upstem turn, the downstem turn, the parallel turn and the parallel step turn. Each turn was divided into the initiation phase and the first and second steering phases. Most of the statistically significant differences (P < 0.05) between the two groups were found for the initiation phases of the four turns. Both the hip axis-hand axis angle and the edging angle of the uphill ski were significantly different between the two groups for the upstem turn at the beginning of the initiation phase. For the downstem turn, significant differences between the groups were found at the start of the initiation phase for the hip axis-hand axis angle, the shoulder axis-fall line angle, and the edging angle of the uphill ski. The standard deviation of the distance between the tips of the two skis over the second steering phase also differed significantly between the two groups. For the parallel step turn, significant differences were found at the start of the initiation phase for the edging angle of the downhill ski and the downhill ski to movement direction angle. Significant differences were also found for the edging angle of the downhill ski in the middle of the second steering phase and the shoulder axis to movement direction angle at the end of this phase. For the initiation phase of the parallel turn, significant differences were found for the timing of setting the ski pole, the uphill knee angle at the start of this phase and the range of the knee angle of the uphill leg from the start to the end of this phase. For this turn, significant differences between the two groups were also found for the edging angle of the downhill ski in the middle of the second steering phase and the shoulder axis to movement direction angle at the end of this phase. One of the reasons it was possible to identify a few significant differences only for the turns analysed, was the variability within the intermediate group: for most of the variables analysed, the standard deviation was much higher for the intermediate than for the experienced group.

Biomechanical Phenomena↗
PubMed1998

Predictors of relapse and rehospitalization in schizophrenia and schizoaffective disorder.

In a German multicenter treatment study, 354 patients with schizophrenia and schizoaffective disorder were followed for 2 years. The data collected were taken as a basis for the present predictor study. For the first time, the technique of classification and regression tree (CART) analysis has been employed for this purpose. CART yielded informative data and appeared to be a useful instrument in predictor research. On the outcome variables "relapse" and "rehospitalization," significant predictor variables were found in several areas: neuroleptic treatment, onset and previous course (precipitating factors, first manifestation, hospitalization in the preceding year, suicide attempts), psychopathology (residual type, schizoaffective disorder), social adjustment (marital status, employment, intensity of life, Phillips score), previous life experiences (traumatic experiences and psychiatric or developmental disturbances in childhood), and biology (gender, age). Our investigation confirmed the generally prevalent views regarding the value of neuroleptic treatment, the multifactorial etiology, and the vulnerability stress model of schizophrenia.

Adult↗
PubMed1998

[Spinach powder-induced exogenous allergic alveolitis].

A 51-year old woman developed hypersensitivity pneumonitis to spinach powder, which is used as a food dye. The diagnosis was confirmed by demonstration of IgG2-antibodies in the patient's serum to distinct bands of spinach extract by Western blotting. Furthermore an exposure test with the natural allergen was positive. Severe disease with fever, chills and dyspnoea developed after inhalation of native spinach powder. Arterial pO2 dropped significantly and pulmonary function tests showed severe restrictive impairment and reduction of diffusion capacity. Leucocyte count and the serum concentrations of the cytokines TNF alpha and IL6 and of the soluble IL2-receptor rose significantly in peripheral blood, whereas the concentration of neopterine did not change. 24 hours after exposure bronchoalveolar lavage showed an increase of neutrophils. In lung parenchyma mononuclear interstitial infiltrates and an epitheloid cell granuloma were seen.

Alveolitis, Extrinsic Allergic↗
PubMed1998

Hodgkin's disease-like lymphoproliferative disorders in patients with different underlying immunodeficiency states.

Epstein-Barr virus (EBV)-associated lymphoproliferative diseases are a frequent occurrence in immunodeficient patients. Most commonly seen are polymorphic B-cell lymphoproliferative disorders and malignant B-cell lymphomas. Classical Hodgkin's disease (HD), however, is rare in these patients. In the present study, we attempted to characterize cases resembling HD in patients with a variety of underlying immunodeficiency states using clinical aspects, immunohistochemistry, in situ hybridization, and polymerase chain reaction. All of the six cases that we investigated presented clinically with B symptoms and a short, devastating course. Histologically, they showed a lymphocytic depletion and multiple cells that resembled HD and Reed-Sternberg cells. Many of those were atypical blast cells that stained positively for B-cell surface antigens, such as CD20 and CD79a, whereas others were of the typical HD and Reed-Sternberg phenotype. Another frequent finding, especially in the extranodal sites, was a perivascular arrangement of large blast cells intermingled with small lymphoid cells. All of the cases were EBV-associated (proved latent membrane protein-1 immunohistochemical analysis, EBV-encoded RNA in situ hybridization, and polymerase chain reaction for subtypes A and B), with a frequent coinfection of type A and B. This was in contrast to ordinary HD, which is characterized by single infection of only one strain, i.e., the subtype A in Western countries. Three cases showed clonal B-cell populations, at least at terminal stages of the disease. We describe a lymphoproliferative disorder in immunodeficient patients with features of HD that, in some respects, resembles an EBV-driven lymphoproliferative disorder seen in cases of fatal infectious mononucleosis. We conclude that clinical and pathologic features of these disorders might cause some problems for histologic differential diagnosis and might represent a separate entity of their own in immunodeficient patients.

Adult↗
PubMed1997

Rearranged Ig heavy chain DNA is detectable in cell-free blood samples of patients with B-cell neoplasia.

Tumor-derived DNA has been shown in various cell-free body fluids. In this study, soluble tumor-derived DNA was analyzed in serum and plasma samples of patients with B-cell malignancies. DNA was extracted from tumor cell specimens as well as serum and plasma samples collected from 110 patients with non-Hodgkin's lymphoma and acute B-precursor lymphoblastic leukemia and was subjected to polymerase chain reaction (PCR) analysis for rearranged immunoglobulin heavy chain DNA. In 54% of serum or plasma samples analyzed at different times before and during treatment, clonal DNA from a rearranged immunoglobulin heavy chain locus was detectable. When examined at diagnosis and before any treatment, clonotypic DNA was found in serum or plasma of 86% of the patients. Serum or plasma from patients with systemic or bulky disease was uniformly PCR positive, whereas clonotypic DNA was also recovered from the serum or plasma from the majority of patients with limited disease stages. Degradation of clonal DNA by nucleases in vitro was shown to be one cause of false-negative PCR results. This technical drawback can be relieved by adding a nuclease inhibitor like EDTA, ie, by using plasma instead of serum for PCR analysis. Treatment of patients with cytotoxic drugs was followed by rapid clearance of DNA from the peripheral blood, suggesting that soluble tumor-derived DNA might be associated with viable and proliferating tumor cells. Follow-up studies showed a close correlation of persisting soluble tumor-derived DNA with resistant disease or early relapse. In summary, these data suggest that tumor-derived DNA can be detected in serum or plasma of the majority of patients with B-cell malignancies and that testing of serum or plasma for tumor-associated DNA may be a novel parameter for monitoring response to treatment.

Base Sequence↗
PubMed1997

Thyreoglobulin and violent asphyxia.

The concentration of thyreoglobulin (tg) was determined for death caused by hanging, strangulation by ligature, and throttling. Cases of sudden death (traumatic aortic rupture, penetrating wounds of the heart) were used for comparison. The mean values in cases of hanging (149.9 +/- 202.3 ng/ml), strangulation by ligature (193.1 +/- 173.3), manual strangulation (561.6 +/- 173.9) are distinguishable from violent acute deaths (23.3 +/- 27.6) and living healthy individuals (17.3 +/- 16.1). By means of statistical comparisons, significant differences were found between throttling and strangulation by ligature and between throttling and hanging (adjusted P < 0.001). In connection with examination of the bodies high tg values can be regarded as a vital reaction in obstructive asphyxia.

Asphyxia↗
PubMed1997

[Tube feeding of children with cystic fibrosis].

Three children suffering from cystic fibrosis, two girls aged 15 and 7 and one boy aged 18 years, presented growth retardation resulting from increased energy requirements and relative undernourishment. Since oral hyperalimentation was insufficiently efficacious, extra nutrition was administered by tube (at night): a naso-gastric tube, a percutaneous endoscopial gastrostomy catheter or an intragastric tube with a stopper in the skin. All three patients achieved a higher percentile line in the weight/height growth diagram, with stable or improved pulmonary function.

Adolescent↗
PubMed1997

Enhanced expression of ICAM-1 (CD 54) in human skin wounds: diagnostic value in legal medicine.

OBJECTIVE: It was the aim of this study to characterize the vitality and the age of skin wounds by verifying the presence of ICAM-1. MATERIAL: 132 intravital human skin wounds (time since injury 15 min-19 days) were investigated by immunohistochemistry. The samples were taken either after surgical treatment of the wounds or from autopsy cases. METHODS: CD 54 was detected in paraffin sections by monoclonal antibodies after an autoclaving pretreatment using the ABC peroxidase technique. RESULTS: In samples of uninjured skin (n = 30), ICAM-1 appeared at a low concentration on keratinocytes and the endothelial cells of blood vessels. In injured skin, an increase in the surface expression was found to occur initially after a post-trauma interval of 2 h. The evaluation was made on a semiquantitative basis. A moderate to strong ICAM-1 expression occurred in 80% of the wounds investigated. CONCLUSIONS: The expression of ICAM-1 correlates with the degree of wound inflammation, which may be considered as an early evidence of the vitality of the wound.

Forensic Medicine↗
PubMed1997

Time dependence of the expression of ICAM-1 (CD 54) in human skin wounds.

To characterize the vitality and age of skin wounds by means of the ICAM-1 pattern, 157 intravital human skin wounds (time since injury ranging from 5 min to 730 days) were immunohistochemically investigated. ICAM-1 was detected in paraffin sections after autoclaving and using the ABC technique in 86% of the wounds investigated. The correlation between ICAM-1 expression and the degree of wound inflammation is weak. Strong positive staining was observed 1.5 h at the earliest and 3.5 days at the latest after the time of injury. ICAM-1 also appeared at low concentrations in samples of uninjured skin (n = 65), on keratinocytes and the endothelial cells of blood vessels. Moderate to strong ICAM-1 expression is a valuable indication of the vitality of the wound. However, at present the detection of ICAM-1 alone is not sufficient to fix the wound age with the accuracy which is required for forensics applications.

Adult↗
PubMed1997

Solute composition and heat shock proteins in rat renal medulla.

The high content of heat shock proteins (HSPs) 25 and 72 in the hyperosmotic inner medulla of the concentrating kidney has been ascribed to the high NaCl and urea concentrations in this kidney zone. To assess the effects of variations in the composition of solutes in the renal medulla on the intrarenal distribution of HSPs, rats were fed either a high- or low-Na diet for 3 weeks. These diets result in greatly differing urine and inner medullary solute composition. Sodium dodecyl sulphate polyacrylamide gel electrophoresis and Western blot techniques were used to analyse HSP25 and HSP72 in the cortex, outer medulla and inner medulla. In addition, the amounts of organic osmolytes (sorbitol, myo-inositol, betaine and glycerophosphorylcholine) and urea in the tissue were determined by high-performance liquid chromatography. Intra- and extracellular electrolyte concentrations at the papillary tip were measured by electron microprobe analysis. In the high-Na group, urine osmolality was about 1000 mosmol/kg lower than in rats fed a low-Na diet, due to lower urea concentrations. The sum of urine sodium and potassium concentrations, however, did not differ between the two groups. Neither in the outer nor in the inner medulla was the sum of the concentrations of organic osmolytes affected by the dietary treatment. The sum of sodium, potassium and chloride concentrations did not differ between the two experimental groups, neither in the interstitial nor in the intracellular compartments. However, the urea content and the amounts of HSP25 and HSP72 were significantly lower in the inner medulla of the group of rats fed a high-Na diet. Our results suggest that urea participates in the regulation of the medullary levels of the HSPs and that both HSP25 and HSP72 are components of mechanisms protecting medullary cells against the deleterious effects of high urea concentrations.

Animals↗
PubMed1997

The response of heat shock proteins 25 and 72 to ischaemia in different kidney zones.

Induction of heat shock proteins (HSPs) following cell injury contributes to the protection of vital cell functions. It was, therefore, of interest to study the effects of transient renal ischaemia on the abundance and distribution of two HSPs, HSP25 and HSP72, in renal tissue using Western-blot techniques. Analyses were performed on the supernatant (HSP25, HSP72) and pellet (HSP25) of homogenates obtained from cortex (CX) and outer (OM) and inner (IM) medulla of the rat kidney immediately after 60 min of ischaemia followed by varying periods of reperfusion. Ischaemia of the left kidney caused HSP25 contents to decrease in CX, OM and IM by 73, 89 and 54% respectively, compared with the corresponding zones of the contralateral control kidney. This initial decrease in supernatant HSP25 was accompanied by an increased abundance of HSP25 in the pellet. Following reperfusion, HSP25 contents in the supernatant gradually increased in CX and OM, reaching, after 24 h, values that were 5.4- and 2.5-fold higher, respectively, than those in the control kidneys. After 7 or 14 days of reperfusion, HSP25 contents had not completely normalised in CX, but had reached control levels in OM. In IM, the HSP25 content remained below control throughout the entire reperfusion period. HSP72 (supernatant) was below the detection limit in the CX of the control kidney. Similar to the level of HSP25, that of HSP72 was also markedly lower in OM and IM immediately after ischaemia. The intrarenal distribution of HSP72 and the sequence of zonal changes in HSP72 contents were similar to those observed for HSP25. These results are compatible with the view that, during ischaemia and the initial reperfusion period, HSP25 migrates from the cytoplasmic compartment (supernatant) into the nucleus and/or associates with cytoskeletal structures. The observation that both HSP25 and HSP72 are transiently induced in CX and OM, but not in IM, may be explained by the fact that, while all kidney cells are exposed to ischaemic stress, only inner medullary cells experience a major postischaemic attenuation of osmotic stress.

Animals↗
PubMed1997

Non-suppurative myocarditis in piglets associated with porcine parvovirus infection.

The involvement of porcine parvovirus (PPV) in the aetiology of non-suppurative myocarditis in sucking piglets was investigated by a polymerase chain reaction (PCR), designed to assess the presence of viral genome in formalin-fixed paraffin wax-embedded tissue of diseased animals. Myocardium and lung of stillborn piglets with a confirmed PPV infection were used to set up the PCR amplification method. Subsequently, 20 myocardia with inflammatory lesions were examined in parallel with 20 myocardia without lesions, from age-matched control piglets. Tissues were first tested for the presence and the integrity of porcine DNA by amplifying a sequence encoding the highly conserved nuclear protein histone H4. Tissue from 15 out of 20 animals with myocarditis contained amplifiable histone H4 DNA and in 12 of the 15 histone H4-positive samples, PPV DNA was detected. It proved possible to amplify histone H4 DNA in all 20 negative controls (without myocarditis), and PPV DNA was detected in three cases. In-situ hybridization with a digoxigenin-labelled probe homologous to PPV was performed in four PCR-positive cases of non-suppurative myocarditis. In two animals several positively stained nuclei were observed in the myocardium, within or close to the mild inflammatory cellular infiltrates. These results strongly suggest that PPV can cause non-suppurative myocarditis in sucking piglets.

Animals↗
PubMed1997

Prostaglandin E2 stimulates expression of matrix metalloproteinase 2 in cultured rat mesangial cells.

Prostaglandins of the E-series have been demonstrated to reduce extracellular accumulation of collagens in some models of glomerulonephritis. This effect is partially due to reduction of collagen formation by mesangial cells. The potential effects of prostaglandins on the expression of collagen degrading enzymes in mesangial cells are largely unknown. Since rat mesangial cells generate a matrix metalloproteinase 2 (MMP-2) that specifically degrades collagen type IV, the effects of prostaglandin E2 (PGE2) on transcription, steady-state mRNA levels, extracellular enzyme activity and protein concentration of this proteinase were evaluated. Mesangial cells (MC) were incubated with PGE2 (2 microM) for different time-periods (1 to 48 hr), and steady-state mRNA levels of MMP-2 were determined by Northern blotting. PGE2 increased MMP-2 mRNA levels beginning at one hour of incubation and remained elevated up to 24 hours. Nuclear run off experiments revealed that the PGE2-induced increase in mRNA expression for MMP-2 is due to stimulated gene transcription. Western blot analysis and zymography revealed that MMP-2 protein production and enzyme activity was also enhanced by PGE2. The cAMP analogue 8-bromo-cAMP increased MMP-2 mRNA levels, suggesting that PGE2-induced generation of intracellular cAMP plays a role in MMP-2 induction in MC. These studies demonstrate that PGE2 stimulates the transcription, protein formation and enzyme activity of MMP-2 in cultured rat MC. This effect may contribute to the prostaglandin mediated reduction of extracellular collagen deposition in glomerulonephritis.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1997

Mutation (677 C to T) in the methylenetetrahydrofolate reductase gene aggravates hyperhomocysteinemia in hemodialysis patients.

Hyperhomocysteinemia is frequent in hemodialysis patients and represents an independent risk factor for vascular disease in these patients. Elevated total homocysteine (tHcy) plasma levels can results from defective remethylation of Hcy to methionine due to decreased activity of the enzyme methylenetetrahydrofolate reductase (MTHFR). A genetic aberration in the MTHFR gene (677 C to T substitution) has been shown to result in reduced MTHFR activity. We tested the hypothesis that elevation of tHcy plasma levels in hemodialysis patients is influenced by the 677 C to T mutation of the MTHFR gene and examined the relation of the genotype with tHcy, folate and vitamin B12 plasma levels in these patients. The allelic frequency of the MTHFR mutation was evaluated in 203 patients maintained on chronic hemodialysis treatment. Total Hcy, folate, vitamin B12 levels and the MTHFR mutation were analyzed in 69 of the 203 patients and in 69 age- and sex-matched healthy control subjects. The allelic frequency of the 677 C to T transition in the MTHFR gene in hemodialysis patients was 34.7% versus 35.5% in healthy controls. Of 203 patients 26 (12.8%) were homozygous for the mutation (+/+) versus 10.2% in healthy subjects. The heterozygous (+/-) genotype was identified in 43.8% of patients versus 50.7% in controls. The mean tHcy level in hemodialysis patients was 28.7 +/- 11.0 mumol/liter versus 10.0 +/- 3.0 mumol/liter in control subjects. The mean tHcy levels were 36.4 +/- 13.4 mumol/liter in (+/+) patients and 12.2 +/- 4.5 mumol/liter in (+/+) controls, 28.7 +/- 10.8 mumol/liter in (+/-) patients and 9.9 +/- 2.7 mumol/liter in (+/-) controls and 25.4 +/- 8.5 mumol/liter in (-/-) hemodialysis patients versus 9.7 +/- 2.8 mumol/liter in (-/-) controls: There was no significant difference of folate and vitamin B12 concentrations in patients and controls with different MTHFR genotypes. Analysis of covariance including age, gender, folate concentrations, vitamin B12 levels, albumin and creatinine as covariables revealed a significant influence of the (+/+) genotype, albumin and folate status on tHcy levels in hemodialysis patients. Together, our data demonstrate that the extent of hyperhomocysteinemia in hemodialysis patients is not only the result of uremia or folate status, but is also genetically determined by the (+/+) MTHFR genotype. The presence of the 677 C to T mutation in the MTHFR gene does not appear to represent a risk factor for development of end-stage renal disease.

Adult↗