bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative anatomical and neurohistological observations on the tongues of elephants (Elephas indicus and Loxodonta africana)
Authors: Kubota Kinziro 
Published: February 2005

AbstractFrozen sections from Indian and African elephant tongues were investigated neurohistologically. On the dorsum there are 3 to 5 vallate papillae. Foliate papillae consisting of 18 to 27 clefts are observed in the posterolateral region of the tongue. Wart‐like papillae are distributed along the lateral border of the tongue from the foliate papillae region to the apex. Vallate and foliate papillae contain serous glands but have no taste buds. They are supplied with abundant lamellated corpuscles of Pacinian type in their upper mucosa. The wart‐like papillae are composed of two or more papillae, each of which has many secondary papillae supplied with plexiform thin and thick nerves. They bear a few taste buds and contain lamellated corpuscles of Pacinian type.From these neurohistologic characteristics wart‐like papillae should be regarded as a receptive organ for secretion of the lingual glands. Lamellated corpuscles of Pacinian type are widely distributed over the whole surface of the tongue. The histologic location of these two structures is of interest in suggesting that they together play important roles as receptors of taste and tactile sensations during mastication of food. Double motor end plates are found on single muscle fibers. The mixed glands which are plentiful in the inferolateral area of the tongue are in close topographic relation with the wart‐like papillae.
The antiestrogenic and antiandrogenic activities of progesterone in the defense of a normal fetus
Authors: Dorfman Ralph I. 
Published: February 2005

AbstractThe hypothalamic‐anterior pituitary‐gonadal system of the infant rodent is sensitive to sex hormones. In the female, an increase in androgens leads to improper development of an anovulatory ovary. In the male, an increase in estrogens prevents the testis from attaining normal development. These atrophic testes show serious abnormalities of spermatogenesis and androgen biosynthesis. Progesterone, which may function as both an antiestrogen and an antiandrogen, can prevent these abnormal developmental changes.It is suggested that a function of progesterone, in pregnancy, may be the defense of the fetus against increased concentrations of androgens and/or estrogens.
Erythropoiesis in the bone marrow of the fetal rabbit
Authors: King John E. , Ackerman G. Adolph 
Published: February 2005

AbstractAlthough the extravascular origin of erythrocytes from undifferentiated mesenchymal or reticular cells in mammalian bone marrow is generally accepted, the morphological evidence on which this concept is based has not conclusively ruled out the possibility of endothelial cell contributions to erythropoeisis or of the preferential localization of developing erythrocytes within endothelial cell‐lined spaces. Since conventional methods of tissue preparation have produced artifacts which obscure the fine details of marrow architecture, the re‐examination of this problem using newer histological and fixation methods permits a more critical study of the bone marrow in nearly artifact free sections.Ribs and long bones of 65 rabbits, ranging from 18 days of gestation to the second day after birth were removed, fixed intact with 10% aqueous acrolein, decalcified in 5% aqueous nitric acid and embedded in plexiglass‐methacrylate. Two micron sections stained with toluidine blue were examined with the light microscope. Serial paraffin sections of formal‐Zenker fixed material also were examined.Morphological studies conclusively indicate that erythrocytes develop extravascularly arising from mesenchymal or reticular cells in the fetal bone marrow. Mature erythrocytes enter the circulation through discontinuities in the sinusoidal walls. Neither endothelial cells or blood‐borne lymphocytes make an apparent contribution to erythropoiesis. The first hemopoietic cells to form in the fetal marrow are determined and develop along the erythrocytic line. These proerythroblasts initially arise randomly in the marrow parenchyma and are not in obvious association with the sinusoids. Subsequent maturation and proliferation of the primitive erythrocytic cells result in the formation of colonies of erythrocytic cells at all stages of development. As these colonies enlarge, the erythrocytic elements come in close association with the sinusoids. In later stages of marrow development, developing erythrocytic and granulocytic cells become intermixed and more randomly associated in the extravascular space of the marrow.
Further observations on resorption in guinea pigs following injections of trypan blue
Authors: Hoar Richard M. , King Theodore J. 
Published: February 2005

AbstractPregnant guinea pigs were injected with 2 ml of either 1% saline or 1% trypan blue of the eleventh day of gestation and sacrificed on days 12, 13, 14, 15 or 20 or laparotomized on day 15, examined for implantation sites and sacrificed on days 25, 30 or 35.Trypan blue increases both the number or pregnancies affected and the number of embryos resorbed within 24 hours after injection. Laparotomy on day 15 augmented the above effects in both saline and trypan blue‐injected females. This increase is superimposed upon the number of resorptions already established for the two groups. Evidence is presented which suggests that resorption of guinea pig embryos can be so complete as to leave no indication of the original presence of the embryo or its placenta. This can occur within as few as five days.
Ultrastructure of the carotid body of the cat as revealed by various fixatives and the use of reserpine
Authors: Duncan Donald , Yates Robert 
Published: February 2005

AbstractCarotid bodies from 11 cats were prepared for study with the electron microscope. All cats used were initially healthy and weighed from 1.5 to 4.0 Kg. Four cats were given daily doses of reserpine 1.5 mg/Kg for 2, 3, 4 or 12 days; the other cats were untreated. Carotid bodies were fixed by immersion in Dalton's fluid, collidine buffered osmic acid or 3% potassium permanganate in 0.1 M phosphate buffer. Other carotid bodies were fixed by perfusion with buffered formalin or with 3% glutaraldehyde in phosphate buffer. Each fixative produced distinct differences in the appearance of the carotid body, particularly in the size and opacity of the granules within the characteristic vesicles of glomus cells (type I). After Dalton's fixative the granules were faint and inconspicuous whereas after osmic acid fixation the granules were very dense but small in comparison to the size of the enclosing vesicular membrane. Aldehyde fixation resulted in very dense granules that almost completely filled the vesicles but permanganate fixation produced vesicles that were devoid of the dense central cores except for a very few. Carotid bodies from reserpine treated cats that were fixed in osmic acid displayed empty vesicles while those from reserpinized animals fixed by perfusion with glutaraldehyde revealed granules that differed little from normal in numbers, size and density. However, vesicles in the adrenal medulla and in sympathetic nerve endings in the pineal gland from the same animals contained empty vesicles. The results are regarded as evidence of a different degree or method of binding between catecholamines and other components of the vesicles in glomus cells when compared to similar vesicles in sympathetic nerve endings and the adrenal medulla.
Brain abnormalities in early chick embryos infected with influenza‐a virus
Authors: Robertson G. Gordon , DeBandi Harry O. , Williamson Alice P. , Blattner Russell J. 
Published: February 2005

AbstractChick embryos were inoculated with influenza‐A virus over the blastoderm at 42–50 hours incubation (37°C). Surviving embryos were harvested 24 hours later, Grossly and microscopically, the developing brain exhibits a type of abnormality in which the neural wall is highly convoluted with folds projecting into the ventricular cavities, suggesting “overgrowth” of the neural tissue.A comparison of measurements on projection drawings of serial sections of virus inoculated and control embryos at comparable developmental stages indicates that the ventricular surface area, volume of brain tissue and volume of the ventricular cavity are markedly less in the experimental embryos, but average thickness of the brain wall is greater. There are fewer nuclei and mitotic figures in experimental embryos, although average nuclear and mitotic densities and mitotic index are approximately the same as control values.It is evident that the characteristic neural defect is not due to excessive growth, since the volume of brain tissue and number of cells are consistently less in experimental embryos. It is concluded that the virus infection results in an inhibition of growth of the brain wall, and that the increased thickness and foldings must result from collapse of the brain which in turn may be due to a decrease in the amount of ventricular fluid.
The ultrastructure of the myometrium of the rat with special reference to the innervation
Authors: Silva Douglas G. 
Published: February 2005

AbstractAn ultrastructural study of the rat myometrium revealed the presence of a number of nerve bundles, many of which were associated with either muscle cells or blood vessels. The nerve fibers were found to contain agranular and granular vesicles of widely varying proportions and the spatial relationship between nerve fibers and muscle cells in the myometrium was comparable to that found in smooth muscle generally.A study of regions of close apposition between muscle cells showed three types of “cellular contacts.” In the first type the opposing muscle cells are separated by a gap of about 200Å with filamentous structures extending across the gap. In the second type the opposing plasma membrane are in direct contact. The third type consists of regions of cytoplasmic continuity between adjacent cells. It is suggested that the “cellular contacts” provide a path for impulse transmission between muscle cells.
Ultrastructural aspects of fibrogenesis and osteogenesis in tissue culture
Authors: Winell M. , Bassett C. A. L. , Wiener J. , Spiro D. 
Published: February 2005

AbstractThis electron microscopic study of 11 day old chick tibiae cultured for 7 and 14 days has demonstrated significant changes in the exposed, cut, cartilaginous surfaces of the explants. Many chondrocytes had degenerated near these surfaces and, in the lacunae of these cells, 640Å‐banded collagen fibrils appeared. The diameters of these fibrils varied widely and, sometimes, exceeded 4,000Å. The non‐banded filaments of the normal, cartilaginous, extracellular matrix were replaced by 640Å‐banded collagen fibrils near the cut surfaces of the explants. These fibrils had a narrower (500Å) and more uniform diameter than those in the lacunae of degenerated chondrocytes. This study also has confirmed the occurrence of osteogenesis in vitro. The collagenapatite and matrix‐cell relationships were similar to fiber (embryonic) bone. Two types of cells resembling osteocytes and osteoblasts were found in the newly mineralized matrix formed in culture. Mineralization in the zone of outgrowth was incomplete and focal. In some regions the hydroxyapatite crystals were larger than usual, measuring 1,000–2,000 Å in length. Longitudinal sections of collagen fibrils in the zone of outgrowth revealed electron‐dense granules along the course of the fibrils. These granules exhibited no preferred orientation with respect to the band or interband regions.
The origin of intra‐arterial cells in the pregnant uterus of the macaque (Macaca mulatta)
Authors: Beck A. J. , Beck F. 
Published: February 2005

AbstractAn investigation into the source of the cells present in the endometrial arteries of the pregnant Macaque is presented. By comparing the levels of sex chromatin found in these cells with those in fetal cytotrophoblast and in maternal endometrial stroma it was possible to determine that they are essentially of fetal origin.
Gross and microscopic observations on the communicating branch of the facial nerve to the lesser petrosal nerve
Authors: Vidić Branislav , Young Paul A. 
Published: February 2005

AbstractThe contents of the facial canal (first and second parts of the facial nerve, and geniculate ganglion), the tympanic plexus, the greater and lesser petrosal nerves, and all intervening connections were dissected in 40 cadavers. This entire nerve complex was removed in 30 cases, and in parts in ten cases, dehydrated, and stained with Sudan Black B or Protargol. A constant communication from the second part of the facial nerve, the geniculate ganglion, or the greater petrosal nerve was observed to pass to the lesser petrosal nerve in all dissections. A review of the literature indicates other points relative to the exchange of autonomic fibers between the facial and glossopharyngeal nerves.
Histologic and physiologic comparisons of the thyroid glands of the wild and domesticated norway rat
Authors: Mosier H. David , Richter Curt P. 
Published: February 2005

AbstractA comparison of the histological pattern of the thyroid glands of 138 wild and 157 domesticated Norway rats showed that the domesticated rat has smaller epithelial cells, greater uniformity in the size of follicles, larger follicular lamina, and fewer vacuoles in the intrafollicular colloid. These differences are not present at birth but develop gradually with age. Hypophysectomy causes a loss of these differences and results in an identical histologic pattern of atrophy in the two strains of rats. There is greater uniformity of thyroid I131 uptake and labelling of the components of thyroglobulin in the domesticated rat, but the average percent uptake of I131 in the thyroid glands of both strains is the same.These differences may be accountable partly on the basis of different reactions to the environment conditioned by different temperaments in the two strains, by actual differences in the environment, and by genetic differences.
Congenital malformations induced by alloxan diabetes in mice and rats
Authors: Takano Kiichi , Nishimura Hideo 
Published: February 2005

AbstractTwo separate experiments were carried out. (1) Alloxan was injected subcutaneously into ICR female mice at 200 mg/kg on day 0 (zero) of gestation. In the animals which became persistently diabetic, 27.5% of the conceptuses underwent resorption or death and 7.2% of surviving fetuses showed gross malformations, including exencephaly, spina bifida and cleft palate. In nondiabetic experimental animals there was no increase in fetal mortality or malformation rate. (2) Wistar rats were treated by alloxan intraperitoneally at 160 mg/kg on the seventh day of gestation. Again, only in cases of persistent diabetes were there raised fetal mortality and high incidence of external and internal malformations (50.0% of survivors abnormal), including cataract, hydronephrosis, microphthalmia, exencephaly and cleft palate. When glucose concentration was determined in the embryo and amniotic fluid on the eleventh and thirteenth days of gestation, it was found to be much higher in the diabetic than in the control or the nondiabetic treated animals. The embryonic glucose level was always slightly lower than that of the maternal blood.
Cholinesterase activity in the harderian gland of anas domesticus
Authors: Fourman Julia , Ballantyne Bryan 
Published: February 2005

AbstractThe histochemical localization and quantitative levels of acetylcholinesterase and butyrylcholinesterase have been determined in the Harderian glands of normal ducks and ducks fed with salt to increase their serum sodium concentrations; there was no significant difference between the two groups.Acetylcholinesterase was present at a mean concentration of 68.2 μM/gm/hour (range 65.5 – 72.7 μM/gm/hour) in the normal animals and 67.6 μM/gm/hour (range 63.8 – 76.4 μM/gm/hour) in the salt‐fed group; the enzyme was present in nerves related to blood vessels. Butyrylcholinesterase was present at a mean concentration of 42.5 μM/gm/hour (range 20.4 – 58.7 μM/gm/hour) in the control animals and 40.2 μM/gm/hour (range 29.3 – 61.3 μM/gm/hour) in the salt‐fed group; the enzyme was present in epithelial cells and in nerves related to blood vessels similar to those containing acetylcholinesterase. There was a close correlation between the subjective assessment of cholinesterase activity based on histochemical techniques and the amount quantitatively measured.The gland probably secretes mucus and lipids; the epithelial butyrylcholinesterase may play a role in lipid metabolism in the tissue. The nerves may regulate the flow of blood through the gland.
Fiber sizes and capillary to fiber ratios in skeletal muscle of exercised rats
Authors: Carrow R. E. , Brown R. E. , Van Huss W. D. 
Published: February 2005

AbstractThirty male rats (Sprague‐Dawley), 25 days of age, were placed in exercise cages for seven days. They were matched into trios on the basis of the last four days total exercise and randomly placed in three groups: sedentary, spontaneous exercise and forced exercise. For the next 35 days, the sedentary group was permitted no exercise other than that allowed by their small individual cages. The spontaneous group remained in activity cages while the forced group in addition to being in activity cages, swam one 30‐minute period each day with weights equal to 20% of the body weight attached to their tails. At the end of the 35‐day activity period, the animals were sacrificed. The hind limbs were injected with India ink, embedded in gelatin and cut on the freezing microtome. The cross‐sectional area of red and white fibers from the gastrocnemius muscles were measured by using the polar planimeter. Ink‐filled capillaries were counted, in conjuction with fiber measurements.With forced and voluntary exercise programs there was a greater increase in crosssectional area of the red than of the white fibers. Under the same conditions, the increase in the number of capillaries per fiber was greater for white than for red fibers.
The myelinated fibers in the aortic nerve of the swine
Authors: Schmidt E. M. , Stromberg M. W. 
Published: February 2005

AbstractThe aortic nerves of 24 Chester White swine were identified electrophysiologically by the synchronization of the recorded action potentials with the cardiac cycle; and the occurrence of the maximum firing rates observed on the oscilloscope during systole. The aortic nerve, thus identified, was traced to the aortic arch in two preparations. The left aortic nerve was a separate bundle in 15 of 24 (62.5%) swine investigated. In the remaining 37.5% of the swine the nerve was dissected from within the vagus after identification at the level of the nodose ganglion. At this level the aortic nerve leaves the ganglion with the superior laryngeal nerve, runs caudomedially with it a short distance, then loops back laterally into the vagus to run caudally to the arch of the aorta. An aortic nerve was not observed in the right vagus nor in the sympathetic trunk of either side. The myelinated fibers counted from six aortic nerves were less than 10 μ in diameter with the majority in the 2–6 μ range, and averaged 542 in number.
Two cases of intersex in rabbits
Authors: Shaver Evelyn L. 
Published: February 2005

AbstractA description is given of two intersex rabbits, which appeared to be females and, in the course of an experiment, were injected with chorionic gonadotrophin, and then matted with a male. When the animals were sacrificed six days later, the reproductive system was found to be absent except for testes located in the abdomen. On histological examination of the gonads, large amounts of interstitial tissue were found, together with immature seminiferous tubules. The tubules contained large atypical cells, spermatogonia and Sertoli cells. The chromosome number and karyotype, as determined from bone marrow, were male in each case. The intersex pattern and the morphology of the large cells within the seminiferous tubules are discussed.
The histochemistry of carbohydrate‐rich substances in certain ungulate salivary glands
Authors: Leppi T. John , Spicer S. S. 
Published: February 2005

AbstractThe carbohydrate‐rich secretions of bovine, ovine and porcine submandibular and sublingual glands have been investigated histochemically. The strong PAS staining of mucous acini in all the glands indicates presence of mucin rich in residues with vic‐glycols. This staining correlates well with the neutral sugar (hexose or deoxyhexose) content except in the bovine submandibular gland in which other types of residues as perhaps C‐6 linked or terminal amino sugars with vicinal hydroxyls apparently account for PAS staining. Strong staining with a periodate‐para diamine procedure is observed only in the glands with high hexose or deoxyhexose levels and is absent from those with strong PAS reactivity apparently attributable to amino sugars. Digestion with malt diastase diminishes the PAS staining of a mucous secretion in mucous acini of the sheep glands.The mucous acini of the submandibular glands form sialomucin uniformly and afford no evidence for the presence of a sulfomucin. The basophilia of this sialomucin in sow and ewe is fully susceptible to sialidase. Sialomucin basophilia in the bovine submandibular gland is only partially digestible, indicating presence of two kinds of neuraminic acid or two sialomucins in this gland.In the sublingual glands the proportion of sulformucin to sialomucin increases in the order cow‐sow‐ewe. The sialomucin in the bovine and porcine sublingual mucous acini revealed as blue‐stained material with the high iron diamine‐alcian blue sequence largely succumbs to sialidase. Much of that similarly demonstrated in the ovine sublingual gland resists digestion, suggesting presence herein of two sialomucins. The sialomucin in all the mucous acini of the ovine submandibular and some mucous acini of the ovine sublingual glands loses azurophilia and undergoes marked decrease in alcianophilia after digestion with malt diastase.Prominent seromucous demilunes in the ovine and bovine glands appear to secrete a sulfated mucosaccharide. The secretion in these sites stains well with the PAS method. The seromucous demilunes in the cow afford evidence also of a mucosaccharide‐containing sialic acid.
Reconstruction of the human sinoatrial node
Authors: Truex Raymond Carl , Smythe Martha Q. , Taylor Margaret J. 
Published: February 2005

AbstractThe superior vena cava and adjacent right atrium containing the sinoatrial node in each of five human hearts was studied histologically in serial section. The tissue block of a 41 year old man was reconstructed in four colors to provide a three‐dimensional model of the sinoatrial node, atrial relations, blood supply and nodal configuration. The resulting model demonstrated the curved course of the compact sinoatrial node and the mural relations of its tapered superior and inferior ends.Microscopic measurements of the boundaries of the five human nodes yielded an epicardial to endocardial mean thickness in the compact body of the node of 1.6 mm, that of the lower node was 0.6 mm. The mean length of the five nodes was 7.3 mm. Such microscopic delineation of the node is more accurate than gross measurements and indicates that the size of this vital mass of pacemaker tissue in man is smaller than the larger measurements usually given in the literature. Small strands of nodal muscle fibers follow longer or shorter courses before they become continuous with the larger more darkly stained atrial cardiac muscle fibers. We found no histologic evidence within the human node, or along its periphery, of continuity between the small nodal fibers and very large atrial fibers.