Biomedical subjects

Holger Sudhoff

Publications and source records attributed to Holger Sudhoff.

21 records · Page 2Linked to original sources

PubMed2003

Immunohistochemical investigations on external auditory canal cholesteatomas.

OBJECTIVE: The aim of the study was to analyze the biological behavior of external auditory canal cholesteatoma (EACC). The expression and distribution of relevant markers such as transforming growth factor-alpha (TGF-alpha), epidermal growth factor-receptor (EGFR), and the proliferation marker MIB 1 were studied in comparison with normal auditory meatal skin. BACKGROUND: EACC are uncommon and knowledge concerning etiology and pathogenesis is limited. Whether this is a unique entity remains controversially discussed. MATERIALS AND METHODS: Immunohistochemical methods were used to study the expression and distribution TGF-alpha, EGFR, and the proliferation marker MIB 1 on 15 tissues samples. Only the spontaneous form of EACC was included in this study. RESULTS: Positive immunoreactivity for the proliferation marker MIB 1 could be demonstrated in keratinocytes in the basal and suprabasal layers of the epithelium. The number of MIB 1-positive proliferating cells in cholesteatoma was significantly higher than in normal external auditory skin. Cholesteatoma epithelium also showed an enhanced expression of TGF-alpha and EGFR. Inflammatory infiltrate was observed in the perimatrix to various degrees. CONCLUSION: These results suggest that similar to the middle ear cholesteatoma, a chronic inflammatory process underlies the EACC, and the inflammatory stimuli may alter keratinocyte proliferation.

Adult↗

PubMed2003

Zoledronic acid inhibits osteoclastogenesis in vitro and in a mouse model of inflammatory osteolysis.

This study assessed effects of the bisphosphonate zoledronic acid (ZLNA) on osteoclastogenesis. To assess the effect of ZLNA on osteoclast formation in vitro, we cultured mouse bone marrow cells under conditions that promote osteoclastogenesis. Administered at concentrations from 10(-6) to 10(-9) mol/L, ZLNA led to a dose-dependent inhibition of osteoclastogenesis. Combined TUNEL staining and histochemical staining for tartrate-resistant acid phosphatase showed that ZLNA induced apoptosis in osteoclasts and monocytic precursor cells. To study the effects of ZLNA in vivo, we placed keratin particles onto the surface of the parietal bone of mice to induce localized inflammatory bone resorption. Three experimental groups received daily subcutaneous injections of ZLNA (1, 3, or 10 microg/kg body weight) from 4 days before surgery until 5 days after keratin implantation. The ZLNA significantly reduced osteoclast recruitment in a dose-dependent manner, but did not affect the degree of inflammation or the mineral apposition rate.

Animals↗

PubMedDate not supplied

Simulating soft data to make soft data applicable to simulation.

BACKGROUND: Biomedical processes are often influenced by measures considered "non-crisp", "soft" or "subjective". Despite the growing awareness of the importance of such measures, they are rarely considered in biomedical simulation. This study introduces an input generator for soft data (input generator SD) that makes soft data applicable to simulation. MATERIALS AND METHODS: Machine learning approaches and standard regression techniques were applied to simulate odour intensity ratings. RESULTS: The performance of all the applied methods was satisfactory and the results can be used to modify systems biological mathematical models. CONCLUSION: Soft data should no longer be discounted in systems biological simulations. Exemplarily, it can be demonstrated that the input generator SD produces results that are similar to those that the simulated system can generate. Machine learning and/or appropriate conventional mathematical approaches may be applied to simulate noncrisp processes that can be used to modify mathematical models of any granularity.

Adult↗