PubMed Health⌕ Search

Biomedical subjects

M Otto

Publications and source records attributed to M Otto.

At least 19 recordsLinked to original sources
PubMed2006

Two consecutive fatal cases of acute myocardial infarction caused by free floating thrombus in the ascending aorta and review of literature.

Free floating thrombus in the ascending aorta is an uncommon source of acute myocardial infarction. We report on two cases of young women who died of acute myocardial infarction caused by a free floating thrombus in the sinus of Valsalva obstructing the coronary arteries' ostia. The first case reports on a 30-year-old pregnant woman who anamnestically had episodes with short loss of consciousness and weakness. The second case presents a 37-year-old woman suffering from multiple sclerosis with no previous history of thrombotic events. The review of literature revealed a predominance of women (eight females and three males). Interestingly, the coronary arteries bear no preference concerning the right (RCA) or left coronary artery (LCA) being more often occluded by a free floating thrombus. Especially, younger women (mean age 45.5 years, range 30-59 years) with no history of cardiac symptoms and without atherosclerotic changes seem to be predispositioned. The hypothesis that thrombus formation in cases without plaque disruption may depend on an endothelial erosion which seems to be more common in younger women and promoted by a hyperthrombogenic state is supported by our two cases. A comprehensive literature search revealed, that these are the first two reports on a free floating thrombus being the cause of fatal acute myocardial infarction in a pregnant woman, respectively, a woman suffering from multiple sclerosis.

Adult↗
PubMed2006

CSF diagnosis of Alzheimer's disease and dementia with Lewy bodies.

Differential diagnosis of Alzheimer's disease (AD) and dementia with Lewy bodies (DLB) is often crucial. CSF Tau protein and Amyloid-beta (A beta) peptides have shown diagnostic value for the diagnosis of AD, but discrimination from DLB was poor.Herein, we investigate CSF of 18 patients with probable AD, 25 with probable DLB and 14 non-demented disease controls (NDC) by A beta-SDS-PAGE/immunoblot and commercially available ELISAs for A beta1-42 and tau. CSF A beta peptide patterns and tau exhibited disease specific alterations among AD and DLB. The ratio of A beta1-42 to A beta1-38 and A beta1-42 to A beta1-37, respectively, in combination with absolute tau, yielded a sensitivity and specificity of 100 and 92%, respectively. We conclude that CSF A beta peptide patterns and tau levels reflect disease-specific pathophysiological pathways of these dementias as distinct neurochemical phenotypes. Combined evaluation of these biomarkers provides a reasonable accuracy for differential diagnosis of AD and DLB.

Aged↗
PubMed2006

Bacterial evasion of antimicrobial peptides by biofilm formation.

Biofilm formation is a main virulence determinant in many bacterial infections. It significantly increases bacterial resistance to antibiotics and innate host defense. In general, the specific physiology of biofilms and the barrier function of the extracellular biofilm matrix determine resistance to antibacterials. However, resistance to antimicrobial peptides appears to be mainly based on the interaction with biofilm and capsule exopolymers. These polymers may work by electrostatic repulsion and/or sequestration of antibacterial substances. As biofilm polymers play an eminent role in biofilm structuring and resistance, their destruction by dedicated enzymes is a promising attempt to prevent colonization and develop treatment for biofilm-associated infections.

Adhesins, Bacterial↗
PubMed2006

[Low-grade-/high-grade-synovitis: synovitis-score as a gold standard?].

BACKGROUND: Synovectomy specimens represent important material submitted from the orthopedist to the pathologist. However, no consistent histopathological grading system for chronic synovitis has been established so far. PATIENTS AND METHODS: The three compartments of chronic synovitis (enlargement of lining cell layer, density of synovial stroma cells, leukocytic infiltrate) are graded semiquantitatively (from 0=absent to 3=strong), and the points for each compartment add up to the synovitis score: 0-1 = no synovitis, 2-4 = low-grade synovitis, 5-9 = high-grade synovitis. A total of 618 synovial specimens (resections n=559, biopsies n=59) from degenerative and inflammatory joint diseases were graded by two independent observers. RESULTS: Median synovitis scores when correlated to clinical diagnoses were: 1, control; 2, osteoarthritis and post-traumatic arthritis; 3, psoriatic arthritis; 5, reactive and rheumatoid arthritis. The differences between rheumatic and non-rheumatic diseases were significant (p<0.001). The correlation between the two observers was high (p<0.001). CONCLUSIONS: The proposed synovitis score enables stratification of chronic synovitis into low-grade (score 2-4) and high-grade (score >4), which is correlated to the nature of the disease (low-grade to non-rheumatic, high-grade to rheumatic), and it therefore contributes to the diagnosis of rheumatic and non-rheumatic joint diseases.

Adolescent↗
PubMed2006

[Differential diagnosis of rheumatoid granuloma].

Rheumatoid granuloma (RG) is histomorphologically defined as a subcutaneous palisading granuloma with central fibrinoid necrosis. Clinically, it presents as a nodule typically localized at pressure points near the joints. From the rheumatic pathological point of view, the main diagnostic challenge is the differentiation of RG from granuloma anulare, especially if clinical information on the site of removal, known diseases, duration of illness, medication and existing American College of Rheumatology (ACR) criteria are missing. Other granulomatous lesions, such as mycobacterial infections, foreign body granulomas, necrobiosis lipoidica or sarcoidosis, can be differentiated from RG by histopathological criteria or by additional examinations such as pathogen specification or PCR. An immunohistochemical marker for the differential diagnosis of granulomas is not yet available. Diagnosis is based on conventional H-E staining, alcian blue-PAS staining, polarizing analysis or PCR. In the following article, the most important granulomatous entities in the differential diagnosis of RG are introduced and the main diagnostic characteristics are discussed.

Arthritis, Rheumatoid↗
PubMed2006

[Wear particles: key to aseptic prosthetic loosening?].

The aseptic prosthetic loosening of hip and knee prosthesis is the most important cause of implant insufficiency. Bone loss as a result of the biological effect of wear particles is the main cause of such loosening. Wear particles develop their biological activity along different cellular pathways, above all via macrophages, foreign body giant cells as well as fibroblasts of the periprosthetic membrane. These cells induce particle-dependent bone resorption by means of proinflammatory cytokines, such as IL-1beta, TNF-alpha, IL-6 and PGE2. These factors induce the activation of osteoclasts as well as the suppression of osteoblasts. Neutrophil granulocytes and lymphocytes do not play an important role in the process of aseptic loosening. The different wear particles, such as ultra-high molecular weight polyethylene, metal particles, ceramic particles and polymethylmethacrylate can be morphologically recognized very easily. From the clinical point of view, the differentiation between acute or chronic implant infection and particle induced prosthetic loosening is very important, with the histomorphological differential diagnosis between septic and aseptic loosening and their combination being the key clinicopathological factor.

Arthroplasty, Replacement, Hip↗
PubMed2006

Proposal for a histopathological consensus classification of the periprosthetic interface membrane.

AIMS: The introduction of clearly defined histopathological criteria for a standardised evaluation of the periprosthetic membrane, which can appear in cases of total joint arthroplasty revision surgery. METHODS: Based on histomorphological criteria, four types of periprosthetic membrane were defined: wear particle induced type (detection of foreign body particles; macrophages and multinucleated giant cells occupy at least 20% of the area; type I); infectious type (granulation tissue with neutrophilic granulocytes, plasma cells and few, if any, wear particles; type II); combined type (aspects of type I and type II occur simultaneously; type III); and indeterminate type (neither criteria for type I nor type II are fulfilled; type IV). The periprosthetic membranes of 370 patients (217 women, 153 men; mean age 67.6 years, mean period until revision surgery 7.4 years) were analysed according to the defined criteria. RESULTS: Frequency of histopathological membrane types was: type I 54.3%, type II 19.7%, type III 5.4%, type IV 15.4%, and not assessable 5.1%. The mean period between primary arthroplasty and revision surgery was 10.1 years for type I, 3.2 years for type II, 4.5 years for type III and 5.4 years for type IV. The correlation between histopathological and microbiological diagnosis was high (89.7%), and the inter-observer reproducibility sufficient (85%). CONCLUSION: The classification proposed enables standardised typing of periprosthetic membranes and may serve as a tool for further research on the pathogenesis of the loosening of total joint replacement. The study highlights the importance of non-infectious, non-particle induced loosening of prosthetic devices in orthopaedic surgery (membrane type IV), which was observed in 15.4% of patients.

Adult↗
PubMed2006

Implant removal.

Explore the source record for details and available documents.

Dental Implants↗
PubMed2006

Implants and age.

Explore the source record for details and available documents.

Adolescent↗
PubMed2005

Bacterial insertion sequence IS256 as a potential molecular marker to discriminate invasive strains from commensal strains of Staphylococcus epidermidis.

The skin commensal Staphylococcus epidermidis has become one of the most important causative agents of nosocomial infections associated with medical devices. Differentiation between invasive S. epidermidis and its commensal counterpart is crucial for clinical decision making. The ica gene locus, which codes for production of polysaccharide intercellular adhesion (PIA), represents a frequently suggested molecular marker for infectivity. Our data demonstrated that production of PIA was not significantly increased among clinical strains, which may explain the controversial results obtained previously on the correlation of ica presence with origin from infection. Therefore, in this study, we attempted to identify novel genes discriminating between invasive and commensal strains based on the comparison of genome sequences. Our results indicated that the bacterial insertion sequence element IS256 occurred significantly more frequently in strains of clinical origin. Importantly, IS256 might thus constitute a molecular marker to discriminate invasive strains from commensal strains of S. epidermidis.

Carrier State↗
PubMed2005

Early age-related cognitive impairment in mice lacking cannabinoid CB1 receptors.

The molecular mechanisms contributing to the normal age-related decline of cognitive functions or to pathological learning and memory impairment are largely unknown. We demonstrate here that young mice (6-7 weeks) with a genetic deletion of the cannabinoid CB1 receptor performed as well as WT mice, or often better, in a number of learning and memory paradigms, including animal models of skill-learning, partner recognition, and operant conditioning. In contrast, the performance of mature mice (3-5 months) lacking CB1 receptors was much worse than that of age-matched WT animals. In most tests, these mice performed at the same level as old animals (14-17 months), suggesting that the decline in cognitive functions is accelerated in the absence of CB1 receptors. This rapid decline in CB1-deficient animals is accompanied by a loss of neurons in the CA1 and CA3 regions of the hippocampus.

Aging↗