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Biomedical subjects

H Eckert

Publications and source records attributed to H Eckert.

At least 19 recordsLinked to original sources

Heteronuclear X-Y double quantum MAS NMR in crystalline inorganic solids. Applications for indirect detection and spectral editing of rare-spin resonances.

Heteronuclear double quantum MAS NMR experiments in the solid state, involving pairs of highly abundant 31P spins and the rare spins 113Cd, 77Se, and 29Si, are described for the three crystalline compounds CdSiP2, CdGeP2, and Ag7PSe6. These experiments offer the opportunity of indirectly detecting the rare-spin resonance via chemical shift evolution of heteronuclear double quantum coherence. For suitable cases, this method results in significantly enhanced detection sensitivities. Criteria for favorable indirect detection experiments are established. Besides offering high sensitivity, the pulse sequence also acts as a heteronuclear double quantum filter, hence providing heteronuclear correlation and useful spectral editing for peak assignments.

Cadmium

Dipolar 31P NMR spectroscopy of crystalline inorganic phosphorus compounds.

The ability of the 90 degrees-t1-180 degrees pulse sequence to produce accurate dipole-dipole coupling information in solids is investigated. To this end, the experimental 31P spin echo decays are measured for eighteen crystalline phosphides and phosphorus chalcogenides and compared with simulations, based on the known internuclear distances in these compounds. The experimental results are generally found accurate in compounds where the dominant contribution to the dipole-dipole coupling arises from nuclei in structurally inequivalent sites with large chemical shift anisotropies. For this situation, the quantum mechanical "flip-flop" term in the dipolar Hamiltonian is suppressed and the dipole-dipole coupling is entirely heteronuclear in character. All of those compounds that do not obey this condition show accelerated spin echo decays due to a fractional contribution of the flip-flop term and possibly incomplete refocusing of chemical shift terms on the time scale of the experiment. The results confirm on an empirical basis that the spin echo NMR technique can provide accurate dipole-dipole coupling information (and thus distance distributions) in disordered solids and glasses.

Crystallization

Proliferative capacity of mononuclear cells in the human lung.

In pulmonary sarcoidosis, a chronic granulomatous disorder with different stages of activity, the proliferative capacity of the alveolar mononuclear cells is unknown. To get a closer look at this proliferation we combined pulse labeling (by means of tritium thymidine incorporation and autoradiography) with an immunocytochemical staining assay. This assay revealed on one single slide simultaneously blue CD4+ lymphocytes, brown CD8+ lymphocytes and red macrophages. We were able to show that CD4+ as well as CD8+ lymphocytes were radiolabeled only in the active state of the disease. But macrophage proliferation occurred independently of the activity of the disease. In other words with this combination of techniques, it is possible to differentiate, on a single slide, three subsets of mononuclear cells, in combination with their proliferative behavior.

Autoradiography

[Immunohistochemically detected activity of lysozyme in sarcoidosis granulomas--a parameter for the activity of the illness process?].

In 30 patients with sarcoidosis we estimated immunohistochemically the activity of lysozyme in correlation to the activity of ACE in serum and found a positive correlation between these two parameters. We conclude, that the lysozyme content of sarcoidotic granulomas, estimated immunohistochemically, may be a useful morphological parameter of the activity of the disease, applicable on formol fixed and paraffin embedded bioptical material.

Adult

[Splenectomy in sarcoidosis].

It is reported about 6 patients suffering from sarcoidosis with splenomegaly. In these cases indication for splenectomy was given by symptoms of hypersplenism, abdominal pain and ineffective cortisone therapy. In general after operation activity of sarcoidosis is unchanged. Different markers of activity were used after a time interval of 2-11 years. In one case it has to be discussed an overwhelming postsplenectomy infection (OPSI).

Adult

[Clinical and histomorphologic findings in Wegener's granulomatosis].

The Wegener's granulomatosis is a rare primary systemic vasculitis. It is diagnosed more frequently in the last years. Because of various manifestations (rhinitis, sinusitis, otitis, arthralgie, "red eye", neuritis, carditis) and different symptomatics the disease is misjudged over month and years. Clinical findings, problems of bronchopulmonary and histomorphological diagnostics and differential diagnosis are discussed. The prognosis is favourable in cases of early and timely diagnosis and therapy.

Adult

[Bronchoalveolar lavage in systemic scleroderma and systemic lupus erythematosus--differential cell values and enzyme cytochemistry].

The aim of the study was to determine the bronchoalveolar lavage (BAL) cell differentiation and the activity of beta-glucuronidase and N-acetyl-beta-D-glucosaminidase in alveolar macrophages. In 12 patients with systemic sclerosis (SS), 4 with systemic lupus erythematosus and 4 healthy controls BAL was performed. The activity of beta-glucuronidase and N-acetyl-beta-D-glucosaminidase was measured semiquantitative by means of cytochemical methods. Lymphocytes and neutrophils in BAL cell differentiation are increased, also the activity of beta-glucuronidase. The activity of N-acetyl-beta-D-glucosaminidase is decreased in SS and SLE in comparison with controls. The activity of beta-glucuronidase seems to be a marker of activity of alveolar macrophages in SS and SLE.

Acetylglucosaminidase