Intramitochondrial rodlet-like inclusions in human leukemic lymphocytes.

Some mitochondria in leukemic cells in two of nine investigated patients with chronic lymphocytic leukemia and in one patient with morphologically less usual form of this disease contained unusual rodlet-like inclusion bodies. These structures were always present in the matrix of frequently dilatated intercristal spaces. The width of rodlet-like inclusions ranged between 10 and 20 nm, their maximal length was 114 nm. All observed rodlet-like inclusion bodies appeared to be composed of fine filaments 2...3 nm in width and resembled the DNA containing structures in mitochondria of few other cell types. In mitochondria of leukemic cells, however, these inclusions represent a further structural abnormality.     

Intramitochondrial transformations during oocyte maturation in the mouse

An electron microscope study of oocyte maturation in the mouse revealed that some mitochondria undergo gradual transformation in their ultrastructural appearance. In very young oocytes these mitochondria were already found to contain vacuoles, one in each such organelle. In somewhat older oocytes more mitochondria displayed vacuoles which generally appeared to be getting larger. These intramitochondrial vacuoles were found to be essentially optically empty structures surrounded by a single membrane. In favorable sections someof the developing vacuoles had a bottle-shaped appearance, the constricted end of which was attached to the inner limiting membrane of the mitochondrion. With further maturation of the oocytes vacuoles having a pear-shaped appearance became evident. An hypothesis was presented outlining the mode of formation of these vacuoles by expansion of the individual cristae. Intramitochondrial transformations occuring during both oogenesis and spermatogenesis in mammals were reviewed.     

Intramitochondrial helical filaments in medullary tubules of the rat kidney

Characteristic helical filaments were frequently found within dilated intracristal spaces of the mitochondria in epithelial cells of renal medullary tubules of normal rats of both sexes. These filaments had a helical structure with right-handed rotation. The approximate dimensions were 4 nm in thickness, 13 nm in helical diameter, and 16 nm in pitch. The filaments were common in all strains of rats examined in the present study but not in animals of other species including mice, guinea pigs, golden hamsters, Mongolian gerbils, house musk shrews, and rabbits. In Sprague-Dawley strain rats, the filaments were found not only in animals of all ages but also in 6-week-old germ-free animals and fetuses at the 18th day of gestation. Even in the same rats, the helical filaments were completely absent in the cortical tubules.     

Intramitochondrial inclusions in various cells of a snake (Elaphae quadrivirgata)

Summary A variety of inclusion bodies occur in the mitochondria of several cell types of the snake, Elaphae quadrivirgata. These lie in the mitochondrial matrix or within the space of the cristae. The inclusions in the matrix are as follows: dense homogeneous and fine granular materials, structures with finger-print appearance and with filamentous and/or crystalloid pattern and fine ring-shaped and/or microtubular structures. The inclusions within mitochondrial cristae are glycogen particles, globular materials, and strand-like structures.These inclusions occur not only during the hibernation period of the snake, but also in the arousal period. Furthermore, some inclusions are encountered in fetal tissues. The functional significance of these inclusions is unknown; however, the present study suggests that they are related to the metabolic activity of the cells.     

Intramitochondrial filamentous bodies in the thick limb of henle of the rat kidney

"Intramitochondrial filamentous bodies" (IMFB) were occasionally found within the matrix of some mitochondria of the thick limb of Henle of the rat kidney, but not elsewhere in the tubular system. Three types were recognized: type I, an accumulation of filaments 55 A thick; type II, a bundle of parallel filaments having the same thickness as those of type I and regular spacing, 87 A apart, from center to center; and type III, consisting of type II with regular light bands of 280 A periodicity and a helical border of prismatic tubular cristae. In addition to these, electron-opaque masses showing variable and faint substructures were found in the matrix of mitochondria. It is suggested that all these IMFB may originate from mitochondrial cristae and that type II IMFB may be an intermediate developmental form between type I and type III. After uranyl acetate staining, IMFB and the membranes of prismatic tubular cristae showed highly increased electron opacity. The literature has been reviewed for reports of intramitochondrial filamentous inclusions in various types of cells. These inclusions have been classified according to their structural characteristics and the localization in the mitochondria and compared with IMFB reported herein.     

Reproductive seasonality in the Indian pygmy field mouse,Mus terricolor

The Indian pygmy field mouse, Mus terricolor, is a tiny, yet economically and ecologically important crop pest found throughout South-East Asia. There are no systematic reports exploring its reproductive physiology. We report the presence of distinct periods of annual reproductive activity and quiescence in M. terricolor. Body weight in males and females, relative weights of testis, epididymis and seminal vesicle in males, ovarian and uterine weight in females, gonadal histomorphic changes, testicular and ovarian cholesterol, sialic acid in epididymis, fructose in seminal vesicle, uterine protein content, melatonin in males and females, testosterone in males, estradiol, and progesterone in females were studied over a period of three years in both wild-caught and lab-acclimated mice. The number of Graafian follicles and corpora lutea, and plasma estradiol and progesterone, along with relative weights of ovary and uterus in females exhibited a peak in the months of October–January, compared to June. Based on histomorphic and hormonal status, the major reproductively active season is the winter (short-day breeding). There is a brief period of sub-maximal reproductive activity in April. M. terricolor is reproductively inactive in the summer, monsoons, and autumn. The results establish M. terricolor as a seasonal breeder in the field, with interesting implications for pest management.     

Ultrastructure of globule leucocyte inclusions in the rat and mouse

Summary The fine structure of the globules in globule leucocytes of rat and mouse infected with various parasites has been studied. Best preservation was obtained with glutaraldehyde and subsequent osmium fixation. It is concluded that the structure of the globules is host specific. In rat, the structure is not parasite specific, but in mouse slight differences in the structure of the globules of the globule leucocyte in different experimental conditions suggest a small change in the packing of the sub-units.The authors are grateful to Professor G. M. Wyburn and Mr. R. N. C. Aitken for research facilities and advice. The work was partially financed by Agricultural Research Council Grant No. AG 17/49.