Presence Of Mitotic Figures Research Articles

Electron microscopic features and proliferation of astrocytes in the corpus callosum of the rat.

AbstractThe gold chloride sublimate method of Ramón y Cajal was used to stain astrocytes in the corpus callosum of 60–80 g male rats. The opacity of the metal‐stained astrocytes to the electron beam allowed their study in the electron microscope. It was thus found that metal deposits are absent from the nucleus but are present over two cytoplasmic structures: bundles of filaments and dense bodies.Once the features of astrocytes had been observed in metal stained preparations, it became possible to identify them in sections stained for electron microscopy by the routine uranyl‐lead sequence. The presence of filament bundles in the cytoplasm was the most useful diagnostic feature. Dense bodies also helped. The nucleus was relatively large and light with a very distinct, often irregular nuclear envelope. The rather light cytoplasm contained glycogen granules, with few ribosomes and cisterns of endoplasmic reticulusm. However, a few otherwise typical astrocytes had fairly dark nucleus and cytoplasm.After gaining experience with the electron microscope, it was possible to identify most astrocytes in the light microscope by their nuclear features. Counts of the frequency of astrocytes using either the light or electron microscope revealed that they make up about one quarter of the glial population of the corpus callosum.The main properties of astrocytes seemed to be: (1) plasticity of the cell surface, which infiltrates all available spaces around it; (2) apparent rigidity of the bundles of filaments present in the processes, where they may play a supporting role; and (3) ability of astrocytes to undergo division, as demonstrated both by the uptake of 3H‐thymidine into 1.7% of these cells and by the presence of mitotic figures.

LONG-TERM SURVIVAL OF PATIENTS WITH MYELOMA OF THE VERTEBRAL COLUMN.

Myeloma was seen as an isolated tumor in 55 of 413 patients with apparently solitary vertebral column tumors. Survival for 5 to 21 years was recorded for 18 of the 44 patients who had either normal results from bone-marrow examination or no examination of marrow. Of seven patients who had myeloma of bone marrow in addition to an isolated vertebral lesion, only one lived for 31/2 years. Only six patients remain alive and free of disease after more than five years. Bence-Jones proteinuria and elevated values for serum globulin do not necessarily denote that survival will be brief. Also, the presence of mitotic figures or of a pleomorphic histological picture did not appear to be related to prognosis. Irradiation relieved pain and destroyed localized tumor in most patients, but decompressive procedures were necessary in patients with rapidly progressing paraplegia.

Preliminary results of a study of bacterial protoplasts

Spherical bodies resembling Weibull's protoplasts are formed when certain bacteria (B. megatheriumSalmonella gallinarum,B. mesentericus) are incubated with lysozyme or penicillin in the presence of 10% sucrose, as a stabilizer. The presence of mitotic figures in some of the protoplasts suggests that they are capable of development and regeneration.

ADENOCARCINOMATOSIS IN A GIRL AGED SIX YEARS

We feel justified in reporting this case because of the rarity of the condition in patients of this age. The case brings out the value of the intradermal tuberculin test (0.1 or 1 mg.) in differentiating between a tuberculous and a nontuberculous condition. The presence of mitotic figures in the cells of the punctate was suggestive of a malignant condition rather than of a tuberculous process. A review of the literature has not been attempted in this report. REPORT OF CASE History .—L. B., a white girl, aged 6 years, was first seen in consultation on May 6, 1925. Her chief complaint was an enlarged abdomen and increasing weakness. There had not been a similar condition in the family, nor had there been any tuberculosis or cancer. The patient had been a child somewhat below average health and sturdiness until the present illness had begun. She had had measles at