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Biomedical subjects

M Otto

Publications and source records attributed to M Otto.

At least 91 records · Page 5Linked to original sources
PubMed1998

Diagnosis of Creutzfeldt-Jakob disease by measurement of S100 protein in serum: prospective case-control study.

OBJECTIVE: To analyse serum concentrations of brain specific S100 protein in patients with Creutzfeldt-Jakob disease and in controls. DESIGN: Prospective case-control study. SETTING: National Creutzfeldt-Jakob disease surveillance unit. SUBJECTS: 224 patients referred to the surveillance unit with suspected Creutzfeldt-Jakob disease and 35 control patients without dementia. MAIN OUTCOME MEASURE: Serum concentration of S100 protein in patients with Creutzfeldt-Jakob disease, in patients with other diseases causing dementia, and in the control group. RESULTS: Of the 224 patients with suspected Creutzfeldt-Jakob disease, 65 were classed as definitely having the disease after neuropathological verification, an additional 6 were classed as definitely having the disease as a result of a genetic mutation, 43 as probably having the disease, 36 as possibly having the disease, and 74 patients were classed as having other disease. In the 108 patients classed as definitely or probably having Creutzfeldt-Jakob disease the median serum concentration of S100 was 395 pg/ml (SD 387 pg/ml). This was significantly higher than concentrations found in the 74 patients classed as having other diseases (median 109 pg/ml; SD 177 pg/ml; P = 0.0001). At a cut off point of 213 pg/ml sensitivity for the diagnosis of the disease was 77.8% (95% confidence interval 68.8% to 85.2%) and specificity was 81.1% (70.3% to 89.3%). There was a significant difference in survival at different concentrations of S100 in Kaplan-Meier curves (P = 0.023). CONCLUSION: Measurement of serum concentrations of S100 is a valuable tool which can be used more easily than tests on cerebrospinal fluid in the differential diagnosis of Creutzfeldt-Jakob disease. More studies are needed to determine whether serial testing of serum S100 improves diagnostic accuracy.

Biomarkers↗
PubMed1998

Decrease of S100 beta protein in serum of patients with amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease of unknown origin characterized by loss of upper and lower motor neurons and concomitant astrogliosis. We have investigated the S100 beta protein levels in serum as a marker for astroglia of patients with ALS (n = 41) in comparison to a control group (n = 32). Additionally we have investigated 12 patients at different follow-up time points (minimum 6 months). We could not observe a significant difference of S100 beta protein in patients with ALS in comparison to our control group (P = 0.11) but we could clearly see a decrease of S100 beta levels in the further course of the disease. As S100 beta is also seen as a protein with nerve growth factor activity we assume that the fall of serum levels may reflect the loss of nerve growth stimulation in patients with ALS and suppose that repetitive measurements of S100 beta in serum can be used as an objective marker for disease progression.

Aged↗
PubMed1998

Differential expression of cell adhesion molecules in inflamed appendix: correlation with clinical stage.

The diagnosis of 'early inflamed', 'recurrent' or 'sub-acute' appendicitis is often difficult and accompanied by controversies between clinical data, histological findings, and their interpretation. The expression of the intercellular cell adhesion molecule-1 (ICAM-1), the vascular cell adhesion molecule-1 (VCAM-1), and E-selectin has been studied in 61 appendicectomy specimens for possible use as a diagnostic tool. This study demonstrates a different expression of CAM by endothelial (EC) and mesothelial cells (MC) in the various stages of appendicitis, with early E-selectin and ICAM-1 expression in EC, followed by VCAM-1 in EC and MC. Appendices from patients with prolonged clinical symptoms defined by clinicians as 'chronic' appendicitis showed VCAM-1 expression and occasionally weak expression of E-selectin in EC. In several cases, discrepancies were found between the pre-operative 'clinical' diagnosis, the histomorphological findings, and the immunohistological results. In this context, the expression of E-selectin and VCAM-1 in comparison with the histological features has potential significance in the diagnosis of 'early acute', 'sub-acute' or 'recurrent' appendicitis. In addition, a correlation was demonstrated between the histological stages of appendicitis and the kinetics of CAM expression. The study also indicates that the time course of E-selectin expression in vivo is longer than is suggested from in vitro data.

Acute Disease↗
PubMed1998

Detection of 14-3-3 protein in the cerebrospinal fluid supports the diagnosis of Creutzfeldt-Jakob disease.

The analysis of 14-3-3 protein in cerebrospinal fluid (CSF) was shown to be highly sensitive and specific for the diagnosis of Creutzfeldt-Jakob disease (CJD). However, the predictive value of this test in the clinical diagnosis of, and its relation to, sporadic, genetic, and iatrogenic CJD cases have yet to be established. CSF samples of suspect CJD cases seen in the prospective German surveillance study were tested for the presence of 14-3-3 protein by using a modified western blot (WB) technique. WB detected 14-3-3 protein in 95.4% of definite and 92.8% of probable cases. In two patients classified initially as not having CJD the test was positive, and both were later proved to have definite CJD. The positive predictive value is 94.7% and the negative predictive value is 92.4%. False-positive results in a single CSF analysis were seen in patients with herpes simplex encephalitis, hypoxic brain damage, atypical encephalitis, intracerebral metastases of a bronchial carcinoma, metabolic encephalopathy, and progressive dementia of unknown cause. WB analysis for 14-3-3 protein was positive in only 5 of 10 cases of familial forms of spongiform encephalopathies. CSF analysis for 14-3-3 protein should thus be performed in any case suspect for CJD.

14-3-3 Proteins↗
PubMed1998

In vitro examination of the coronary artery wall after balloon angioplasty using intracoronary ultrasound.

After autopsy 12 human coronary arteries were investigated by intracoronary ultrasound in order to measure the vessel wall dimensions and to detect damage on the vessel wall architecture after balloon angioplasty. Histology revealed artherosclerosis in 11/12 arteries. A total of 41 representative coronary segments were selected for further off-line ultrasound and histological analysis. Intracoronary ultrasound and histological measurements of the vessel wall thickness after balloon dilatation demonstrated a good correlation between the maximum thickness of the intima (histology 0.62 mm vs. intracoronary ultrasound 0.65 mm, r = 0.87) and the intima-media complex (0.80 mm vs. 0.83 mm, r = 0.87), in contrast to a weak one between the minimum thickness (r = 0.46 and r = 0.37). A total of 21 cases of damage occurred during angioplasty; intracoronary ultrasound detected 17. Further analysis showed that it imaged 10 of 11 cases of damage involving more than 30 degrees of the vessel circumference and 7 of 10 cases of damage involving less than 30 degrees of the vessel circumference. After balloon angioplasty of diseased coronary arteries, intracoronary ultrasound is therefore reliable in measuring the maximum wall thickness and in imaging damage involving more than 30 degrees of the vessel wall circumference.

Angioplasty, Balloon↗
PubMed1998

Current trends in biocompatibility testing.

Biocompatibility remains the central theme for biomaterials applications in medicine. It is generally accepted that this term means not only absence of a cytotoxic effect but also positive effects in the sense of biofunctionality, i.e. promotion of biological processes which further the intended aim of the application of a biomaterial. The national and international standards for testing regimes represent a lowest common denominator for such applications and do not necessarily ensure that optimal function will be achieved. The authors' thesis is that biocompatibility testing has scope for extensive development with respect to biofunctionality. The present paper reviews current trends in the in vitro aspects of biocompatibility testing. As well as a critical appraisal of the recent literature, future trends are also stressed, which the authors regard as essential for a meaningful integration of a modern biological approach into new developments in the material sciences. These include the application of modern techniques of cell and molecular biology, the concepts of tissue remodelling, hybrid organ development and encapsulated cell technology.

Animals↗
PubMed1998

[Laparoscopic implantation of catheters for continuous ambulatory peritoneal dialysis].

Continuous ambulatory peritoneal dialysis (CAPD) has become an established procedure and is an equal alternative to haemodialysis (HD) in the management of terminal renal failure. Nevertheless CAPD still plays a minor role compared with HD (10% of all dialyses). CAPD offers advantages in quality of live but is still associated with a significant number of complications. The improvement of surgical technique and development of new peritoneal dialysis catheters (PDK) improved the results of peritoneal dialysis. 3 methods for implantation of PDK are used: the open surgical technique, the blind percutaneous procedure and the laparoscopic method. The latter technique is currently an accepted practice. 10 patients were treated by the laparoscopic method. Additionally to the PDK-tunnel of the abdominal wall we used 2 trocars (1 x 5 mm, 1 x 12 mm). Advantages of this technique are avoiding of perforating lesions, possibility for further operations and a safe implantation of the PDK. Peritoneal dialysis was started 7 days after operation with initially low dialysate volumes. The observed incidence of complications and removed catheters are comparable to the reports in the literature.

Catheters, Indwelling↗
PubMed1998

[Therapy and follow-up of injuries after laparoscopic operations].

From May 1993 to September 1997 we treated 22 patients with complications after laparoscopic surgery. We report on 18 patients after laparoscopic cholecystectomy, three patients after diagnostic laparoscopy and one after TAPP. Two patients died (hepatic failure and without any possibility of definitive therapy) and the injuries of the other 20 patients were repaired.

Biliary Fistula↗
PubMed1997

Elevated levels of tau-protein in cerebrospinal fluid of patients with Creutzfeldt-Jakob disease.

Creutzfeldt-Jakob disease (CJD) is a rare, fatal, neurodegenerative disease caused by a transmissible agent designated as proteinaceous infectious agent (prion). Searching for biochemical markers of CJD, we analysed cerebrospinal fluid (CSF) samples of 53 patients for tau-protein using an enzyme linked immunoassay (ELISA). In a group of 21 patients with definite CJD seen in the German case control study for CJD, tau-protein concentrations in CSF were significantly higher than in two control-groups of patients with other diseases (median 13,153 pg/ml, range 1,533-27,648 pg/ml; P = 0.0001). One group comprised 19 patients who were seen in the same study and were diagnosed as having other dementing diseases (tau concentration: median 558 pg/ml, range 233-1,769 pg/ml). The second control group comprised 13 patients from our hospital with no dementing disease (tau concentration: median 296 pg/ml, range 109-640 pg/ml). We conclude that determination of tau protein levels in CSF is a useful marker for laboratory diagnosis of CJD.

Aged↗
PubMed1997

S-100 protein concentration in the cerebrospinal fluid of patients with Creutzfeldt-Jakob disease.

We evaluated S-100 levels in paired cerebrospinal fluid (CSF) and serum samples in a group of 135 patients referred to the German Creutzfeldt-Jakob disease (CJD) surveillance unit from June 1993 to May 1995. The patients were seen in a prospective case control study. The diagnosis of probable CJD during life was made in any patient presenting with rapidly progressive dementia of less than 2 years' duration, typical periodic sharp wave complexes (PSWCs) in the EEG and at least two of the following findings: myoclonus, visual/or cerebellar symptoms, pyramidal and/or extrapyramidal signs and/or akinetic mutism. Patients presenting with the above clinical signs and symptoms but without PSWCs were classified as possible, while those with a dementia of a duration exceeding 2 years and without PSWCs were classified as other. S-100 was determined in paired CSF and serum samples by a commercially available enzyme-linked immunosorbent assay. In a group of 76 patients with definite and probable CJD, S-100 concentration (median 25 ng/ml, range 2-117) in CSF was significantly higher (P < 0.0001) than in 32 patients diagnosed as other (median 4 ng/ml, range 1-19). Serum levels of S-100 were below 0.5 ng/ml in all groups. At a cut-off of 8 ng/ml an optimum sensitivity of 84.2% with a specificity of 90.6% for the diagnosis of CJD by the determination of S-100 in CSF is obtained. S-100 levels exceeding 8 ng/ml in CSF support the diagnosis of CJD in any patient presenting with rapidly progressive dementia.

Adult↗
PubMed1997

Diagnosis of Creutzfeldt-Jakob disease and related human spongiform encephalopathies.

Spongiform encephalopathies are transmissible diseases (TSE) of animals and humans. With the appearance of bovine spongiform encephalopathy (BSE) in 1986 and in 1996 with the identification of an apparently new variant of the human spongiform encephalopathy Creutzfeldt-Jakob disease (CJD), great concerns of a potential transmission of BSE to humans have been voiced. The agent known to transmit CJD and other human and animal spongiform encephalopathies is designated as prion, i.e., proteinaceous infectious agent, due to the absence of evidence for the involvement of a nucleic acid in disease transmission. In humans the clinical diagnosis of typical CJD cases can now be supported by paraclinical parameters. Electroencephalographic changes, so called periodic sharp wave complexes, are pathognomonic for CJD but by no means specific. The detection of neuronal enzymes in the cerebrospinal fluid (CSF) such as neuron specific enolase (NSE) or glial proteins such as S-100 aids greatly in the diagnosis of a human spongiform encephalopathy. By far the most specific marker in CSF are a group of proteins designated 14-3-3. Current evidence suggests that by including elevated levels of NSE (> or = 35 ng/mL), S-100 (> or = 8 ng/mL) and tau protein in the CSF and the presence of 14-3-3, a laboratory supported diagnosis of CJD can be achieved which in the appropriate clinical setting has a better diagnostic accuracy than the currently used clinical and paraclinical diagnostic criteria alone.

Animals↗
PubMed1997

Stability of bilayer lipid membranes on different metallic supports.

In order to arrive at an optimized s-BLM protocol, the influence of various metallic supports (silver, iridium and stainless steel) of different diameters (from 0.14 to 0.33 mm) on the process of forming and stability of supported phospholipid bilayer membranes was studied. In addition, experiments were made using different membrane-forming solutions, ionic strength and pH. The transmembrane resistance and the current ratio between bare and lipid-coated wire at +670 mV were measured. Teflon-coated stainless steel support (0.33 mm in diameter) covered with 2% crude ox brain fraction of phospholipids was most convenient for the formation of supported bilayer lipid membranes on solid support. The well-known stabilizing effect of cholesterol was confirmed for the s-BLM system. Both the pH in the range 5.0-8.0 (silver and stainless steel supports) and the ionic strength (for all types of supports) in the range from 0.025 to 0.1 mol/l at pH 7.0 were found not to be crucial.

Hydrogen-Ion Concentration↗
PubMed1997

Physiology and cell biology of the endothelium: a dynamic interface for cell communication.

This manuscript presents a brief overview of the physiology and cell biology of the endothelium, which is the basis for understanding the role of endothelial cells in pathological processes as diverse as atherosclerosis, tumour intravasation and multiple organ failure. Following consideration of general aspects of endothelial function in regulating haemostasis, vascular tone and growth, special emphasis will be placed on endothelial regulation of the inflammatory response, which centres on the microcirculation. A particular role in inflammation is played by cell adhesion molecules (CAM), expressed both on endothelial and blood cells. Cell and molecular biological methods to investigate the expression of CAM in endothelial cells in vitro will be presented, as well as novel data, indicating that cytokine-induced up-regulation of CAM in the endothelium may involve signal transduction pathways other than those culminating in the activation of NF-kappa B. Finally, the phenomenon of angiogenesis will be briefly reviewed as a characteristic of endothelial cell activity of central importance to both physiology and pathology and new experimental data presented from an in vitro model to study the ability of individual endothelial cells to form vessel-like structures. In comparative studies to investigate the roles of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor, the dominant role of VEGF in the formation of capillary networks could be unequivocally demonstrated.

Animals↗
PubMed1997

Proximal myotonic myopathy with MRI white matter abnormalities of the brain.

Proximal myotonic myopathy (PROMM) is an autosomal dominantly inherited multisystemic disorder characterized by myotonia, proximal muscle weakness, and cataracts. This disorder is not linked to the gene locus of myotonic dystrophy (DM). We describe three new families with PROMM. In all patients, CTG repeats of the DM gene in DNA from blood leukocytes were normal. MRI of the brain revealed a consistent pattern of marked white matter hyperintensity on T2-weighted images in four patients; two additional patients had similar but mild to moderate MRI abnormalities. The morphology of these abnormalities is unknown. Clinical symptoms of brain disease were not consistent and included mental changes with hypersomnia, parkinsonian features, stroke-like episodes, and seizures. The causative relationship of these clinical features with the MRI white matter abnormalities remains to be established. Our observations suggest that PROMM may involve the brain.

Adult↗