In vitro measurement of the chemical changes occurring within β-tricalcium phosphate bone graft substitutes.

Several mechanisms proposed to explain the osteoinductive potential of calcium phosphates involve surface mineralization ("bioactivity") and mention the occurrence of concentration gradients between the inner and the outer part of the implanted material. Determining the evolution of the local chemical environment occurring inside the pores of an implanted bone graft substitute (BGS) is therefore highly relevant. A quantitative and fast method was developed to measure the chemical changes occurring within the pores of β-Tricalcium Phosphate (β-TCP) granules incubated in a simulated body fluid.

[Pacemaker's twiddler syndrome (author's transl)].

This report demonstrates the results of five observation of the Pacemaker's-twiddler-syndrome, which will not necessarily end in the complete malfunction of the pacemaker unit. Therefore we classify the Pacemaker's-twiddler-syndrome as a partial and a complete form. The partial form is characterized by still effective cardiac stimulation, whereas the complete form can not stimulate the heart muscle because of the retracted electrode.

[Barrett's syndrome (author's transl)].

Barrett's syndrome is a rare serious ulcerative inflammation of the middle or distal parts of esophagus, characterized by heterotopic gastric mucosa within the esophagus. In 4 cases, diagnosis of Barrett's syndrome suspected by means of x-ray examination was confirmed endoscopically and by taking biopsies under vision. The etiology of the disease is not clear.

[Atypical paraproteinemic hemoblastoses (author's transl)].

The symptomatology of typical paraproteinemic hemoblastoses (plasma cell myeloma, Wadenström's macroglobulinemia) are well known. Once suspected, diagnosis of these disorders can easily be established in the majority of cases. Differentiation of benign paraproteinemias requiring no treatment is likewise possible by careful observation of the course of disease and relevant clinical criteria.