Isolation and characterization of two cell types of Coxiella burneti phase I.

Two morphologically distinct cell types of Coxiella burneti phase I have been separated on the basis of unique buoyant densities. When centrifuged to equilibrium in cesium chloride or density gradients of sucrose or Renografin, the cells band in two zones. Electron micrographs of ultrathin sections of the two cesium chloride-separated cell types indicate a considerable number of morphological differences.

Axoplasmic transport in the crayfish nerve cord. The role of fibrillar constituents of neurons.

(a) Axoplasmic transport of tritium-labeled proteins in crayfish nerve cord was confirmed at a slow rate of 1 mm/day. A second proteinaceous component which moves at a rate of 10 mm/day was also detected. Radioautography and biochemical analysis indicate that proteins migrating at these velocities have a perikaryal origin and move caudad within axons as sharply defined peaks.

Acomparison of changes in the mucous glands and goblet cells of nasal, sinus, and bronchial mucosa.

A comparison of mucous gland size in the bronchial and nasal mucosa was performed on material from 24 random necropsies. The Reid index and counts of mucous gland acini were used as measures of hypertrophy. In 14 of these cases the relationship between goblet cell hyperplasia in the sinus mucosa and the presence of chronic bronchitis was investigated by comparing the proportion of goblet cells with the corresponding Reid index.

Fine structure and replication of the kinetoplast of Trypanosoma lewisi.

The kinetoplastic DNA of Trypanosoma lewisi is described as a filamentous body lying within a mitochondrion, with the filaments oriented parallel to the long axis of the cell. The manner of fixation, the replicative state, and perhaps the physiological state of the cell, may result in slight morphological differences among such bodies. The kinetoplastic DNA replicates to form "left" and "right" rather than "upper" and "lower" members, and both the kinetoplast and nucleus incorporate radiothymidine as shown by radioautography.

Studies on the sub-units of triose phosphate isomerase.

The sub-unit structure of rabbit muscle triose phosphate isomerase was studied by determination of the number of unique cysteine peptides. Alkylation of the thiol groups with radioactive iodoacetate in the presence of guanidine hydrochloride gave the S-carboxy[(14)C]methyl derivative of the protein. This was digested with trypsin, and the radioactive peptides were fractionated by ion-exchange chromatography; four main radioactive peaks were obtained, one of which contained two radioactive peptides.