Uniform Granules Research Articles

Fine structural innervation of the dilator muscle of the iris of the albino guinea pig studied with permanganate fixation

Six per cent potassium permanganate fixation was used to study the fine structural autonomic innervation of the dilator muscle of the iris of albino guinea pigs. Axons containing granular vesicles and other axons containing exclusively agranular vesicles within the same nerve bundles were present in the iris dilator muscle in a 2 : 1 proportion. In those axons containing granular vesicles, these vesicles numbered 90% of the total. The granular vesicles were 400–600in diameter with granules of 200–300in diameter. A few vesicles of 800–950in diameter with 400–600granules of variable density were also present. Axons with agranular vesicles contained a homogenous population of agranular vesicles of 350–450in diameter, and represented a third of the total number of axons in a given nerve bundle. The relatively uniform granulation of vesicles in the axons with granular vesicles and their degranulation after sympathetic denervation and administration of reserpine supports the interpretation that these axons represent adrenergic fibers. The consistent morphologic picture of adrenergic nerve fibers obtained with permanganate fixation is useful in correlating morphologic and physiologic studies. The finding of uniform agranularity of agranular cholinergic vesicles in axons within the same nerve bundle, which could contain other axons bearing predominantly granulated vesicles, taken together with pharmacologic proof that these latter are adrenergic suggests a dual innervation to the iris dilator muscle.

FINE STRUCTURE OF A DIATOM CENTROSOME.

The centrosome of the diatom Surirella ovalis is a dense spherical structure 500 mmicro in diamneter with filaments 15 mmicro in diamneter connected to it. The interior is filled with uniform granules but does not contain a typical centriole or clear area. The filaments emanating from it resemble the filaments of the mitotic apparatus, but they are present during interphase and appear to terminate at pores in the nuclear envelope.

Velocity Studies: Diffusion-Controlled Corrosion Reactions

Abstract The velocities of diffusion-controlled corrosion reactions are considered within the larger frame of reactions between solids and fluids (gases or liquids), for reactions with a flat, solid surface and with a spherical surface (uniform granules). Differential equations are given for eight different cases, together with their integration for specific conditions. Examples from the work of the author and from other sources are used to demonstrate the application of six of the eight equations.

病原真菌の微細構造に関する電子顕微鏡的研究

By means of ultrathin section and electron microscopic technic the fine structures ofCandida albicansin yeast phase grown on Sabouraud's dextrose agar were revealed. Fixation of specimens proved to be superior in revealing the fine structures using a 2 % potassium permanganate aqueous solution (at room temperature for 48 hours) than with an osmic acid solution. Embedding was done in a routine method. The results obtained were as follows:The cell wall, relatively thick, consists of the three layers, two electron less dense ones divided by a dense interspace. The cytoplasmic membrane, very thin, is recognized.The nuclear apparatus is surrounded by a continous double-membraneous layer with pores; The nucleolus-like structures are observed as an electron dense region.The mitochondria with cristae mitochondriales are also surrounded by a continous double-membraneous layer as in the nucleus.The endoplasmic reticulum seems to be connected with the outer layers of both nucleus and mitochondria. The structures resembling the lamella, potassium permanganophilic uniform granules and vacuoles are also observed inside the cytoplasm.

THE TWO TYPES OF EPITHELIUM OF THE FINEST BRONCHIOLES OF THE ALBINO MOUSE AS REVEALED BY SUPRAVITAL SILVERIZATION

Two definite types of cells, provisionally designated dark and light, in accordance with the degree of their superficial argyrophilism, are revealed in the terminal bronchiolar epithelium of the albino mouse by supravital silverization. The dark cells are ciliated, and scattered among the light unciliated cells as singles, pairs, triads, or larger groups to form a striking and characteristic surface pattern. The cuticles of the dark cells, far outreached by the neighboring light cells, appear en face as dense crowds of small uniform golden brown granules. Viewed laterally these show as pairs in vertical alignment, and make two layers with a thin lighter band between. The sides and bases are indicated by deposits of black grains. Near the sharply marked margin of the definitive epithelium the dark cells are shorter, more dispersed, and formed like truncated pyramids with narrow densely impregnated apices on some of which are single delicate points instead of discrete cilia. The light cells have bulging villuslike free ends and make flutings on the contiguous dark cells. Small silverized particles sparsely stipple their air surfaces and rounded plaques crown their summits. A similar dicellular picture is found in the terminal bronchiolar epithelium of the golden hamster.

II. On some heterogenetic modes of origin of flagellated monads, fungus-germs, and ciliated infusoria

The “ pellicle ” that forms on infusions of organic matter which are exposed to the air is composed for the most part of a dense aggregation of Bacteria of various sizes and shapes imbedded in a more or less abundant, pellucid, gelatinous material. Very frequently there are also a variable number of intermixed Vibriones and more or less characteristic Torulæ The Bacteria in this layer are mostly placed vertically to the surface, so that an examination of it under the microscope generally reveals the appearance of a stratum densely studded with small though tolerably uniform granules. On attempting to remove a portion of this pellicle, it is found to constitute a more or less coherent membrane. It is now a well-known fact that when two or more Amoebae chance to come into close contact with one another, they may fuse so as to constitute a larger individual of the same kind, which afterwards creeps about and seizes food as its component parts had previously done. Such a process must be classed under the head of Homogenetic Biocrasis ; for, although separate living units fuse to form a new individual, the process is one of mere fusion, and the product is similar in kind although necessarily larger than its components.