bluuebunny/crossref_metadata_2025 huggingface dataset:
Globule leukocytes in the respiratory epithelium of human upper airways: An ultrastructural study
Authors: Baert Johan , Frederix Maria
Published: February 2005

The ultrastructure of globule leukocytes is described in the nasal and tracheal respiratory epithelium of three boys suffering from chronic airway infections. The globule leukocytes lie free in the intercellular spaces and appear to be migratory cells. They are characterized by intracytoplasmic membrane‐bound globules, variable in number, size, shape, and internal structure. The globules may apparently release their content between the neighboring epithelial cells. Human globule leukocytes are also characterized by the presence of intracytoplasmic rod‐shaped bodies, the significance of which is not known. They usually display an extended juxta‐nuclear Golgi apparatus, presumably involved in the formation of the globules. Comparison of the fine structure of the globules in the globule leukocytes with that of the granules found in the subepithelial mast cells does not support a mast cell origin for human globule leukocytes. On morphological grounds, natural killer cells are postulated as a possible source for globule leukocytes. The function of globule leukocytes is briefly discussed. We presume that the globule leukocytes belong to the group of migrating and secreting cells involved in the defense of the organism against foreign material.
Interruption of the middle cerebral artery in 10‐day‐old rat alters normal development of distal collaterals
Authors: Coyle Peter
Published: February 2005

Pial surface arterioles join rami of the anterior and middle cerebral arteries (MCA) in 10‐day‐old normal Wistar rats. Normally, the anastomosing branches differentiate into small‐diameter vessels with significantly greater tortuosity (length) by 56 days of age. After interruption of the MCA in 10‐day‐old rats, large‐diameter, relatively straight collaterals were observed 46 or 90–110 days later. Evidently altered hemodynamic factors, as the result of MCA interruption, prevent the development of a normal pattern of arterioles and augment the development of an anomalous pattern of collaterals in young Wistar rats.
Dose‐dependent movement of cationic molecules across the glomerular wall
Authors: Andrews Peter M. , Bates Sally B.
Published: February 2005

Different concentrations of the polycation polyethyleneimine (PEI) were administered by single intravenous injections or by constant vascular perfusion to the kidneys of Sprague‐Dawley rats. At a fixed time interval after administration of PEI, the kidneys were fixed and the distribution of PEI in the glomerular wall was evaluated by electron microscopy. At the lower concentrations (e.g., 0.005%), PEI bound only to the glomerular endothelial glycocalyx and preferentially to microvillous projections on this endothelium. At higher concentrations (e.g., 0.05%), PEI also bound to discrete anionic sites in the lamina rara interna (LRI) but was rarely seen in the lamina rara externa (LRE). As the concentration of PEI was further increased (e.g., 0.5%), PEI moved deeper into the glomerular basement membrane (GBM) and bound extensively to discrete anionic sites in the lamina rara externa. Although anionic sites in the LRI and LRE appeared nearly saturated following infusion of 0.5% PEI, this cationic molecule was rarely seen to cross filtration slits and pass into the urinary space. At still higher concentrations (e.g., 2%), however, PEI moved freely across the filtration slits, bound extensively to the glomerular epithelial glycocalyx, and induced a narrowing of the filtration slits. When PEI was mechanically perfused through the kidney vasculature for 3 minutes, PEI binding to the epithelial glycocalyx caused very extensive adherence of adjacent podocyte processes and the narrowing and loss of filtration slits. Also in these latter samples, discrete anionic sites in the LRE were no longer apparent and a dense band of PEI was seen under the foot processes. Addition of PEI to culture media containing intact glomeruli revealed that even in the absence of hemodynamic driving forces, the PEI used in the above studies will gradually move across the glomerular basement membrane and bind to anionic sites throughout the glomerular wall. The above observations suggest that anionic sites in the glomerular wall may trap cationic molecules and thereby prevent low concentrations of these molecules from passing deeper into the glomerular wall and gaining entrance to the urinary space.
Effects of L‐azetidine‐2‐carboxylic acid on matrix secretion and Golgi structure in fibroblasts and osteoblasts of the mouse
Authors: Cho Moon‐Il , Garant Philias R.
Published: February 2005

The effect of a proline analogue, L‐azetidine‐2‐carboxylic acid (LACA), on collagenous matrix secretion by periodontal ligament fibroblasts and alveolar bone osteoblasts was studied by light and electron microscopic radioautography after injection of 3H‐glycine; 3H‐glycine labeled material accumulated in the cisternae of the rough endoplasmic reticulum and was not secreted for over 4 hours.

The Golgi complex of both fibroblasts and osteoblasts showed a marked alteration of its composition after LACA administration. All Golgi saccules and collagen secretion granules disappeared within 2 hours. Flattened Golgi cisternae were still present and appeared to be unaffected by the administration of LACA.

These observations indicate that Golgi saccules in collagen‐secreting cells are the initial staging areas for the formation of collagen secretory granules and that there is a close correlation between form and function in the Golgi apparatus of collagensecreting cells.
Ultracytochemical and biochemical evidence for guanylate cyclase in guinea pig testis
Authors: Pascolini Rita , Spreca Antonio , Lorvik Sergio , Fagioli Oliviero , Fanó Giorgio
Published: February 2005

Guanylate cyclase activity has been studied biochemically and cytochemically in guinea pig testis. The results of the biochemical assays indicate an equal distribution of this enzyme between the soluble and particulate fractions, which have a different sensitivity to adenosine triphosphate. The cytochemical results demonstrate that the reaction product of guanylate cyclase is detectable in the interstitial capillary endothelial cells and, in the seminiferous epithelium, mainly at the level of the adjacent surfaces of Sertoli and germ cells of the intermediate and adluminal compartments. Guanylate cyclase activity appears at the level of pachytene spermatocytes and persists throughout subsequent stages of development. The distribution in the seminiferous epithelium seems to indicate that guanylate cyclase is involved in the interrelationships between Sertoli and germ cells during gamete differentiation.
Lectin binding sites on human sperm and spermatogenic cells
Authors: Lee Mao‐Chi , Damjanov Ivan
Published: February 2005

Testes of sexually mature men were studied histochemically with 20 fluorescein isothiocyanate‐labeled lectins. Based on their pattern of reactivity with intratesticular spermatogenic cells, lectins were divided into five groups: (1) lectins reacting with all spermatogenic cells (Suc. ConA, WGA, LCA, PHA‐E, PHAL, STA, MPA, and RCA‐II); (2) lectin reacting with spermatocytes, spermatids, and spermatozoa, but not with spermatogonia (RCA‐I); (3) lectins reacting with spermatids and spermatozoa only (BPA, PNA, SBA, and VVA); (4) lectins reacting only with spermatozoa (HPA, GSA‐I, UEA‐II, and GSA‐II); and (5) lectins with no distinct staining of spermatogenic cells (DBA, LBA, and UEA‐I). All lectins from groups 1–4 were reactive with ejaculated spermatozoa. On the basis of the staining patterns of the head region of ejaculated spermatozoa, four lectin reactivity groups were defined: (1) lectins reacting with the plasma membrane of the whole head (BPA, WGA, LCA, STA, RCA‐II, PHA‐E, PHA‐L, RCA‐I, UEA‐II, and GSA‐II); (2) lectin reacting with the acrosomal cap and postacrosomal region of the plasma membrane (Suc. ConA); (3) lectin reacting with the acrosomal cap region of the plasma membrane (PNA); and (4) lectins reacting with the midregion of the sperm head in a bandlike manner (HPA, VVA, SBA, GSA‐I, and MPA). These data provide a map of lectin binding sites on human testicular spermatogenic cells and ejaculated spermatozoa and show that the distribution of glycoconjugate domains of spermatogenic cell changes during differentiation and maturation.
Morphological changes in atretic graafian follicles during induced atresia in the hamster
Authors: Hubbard C. J. , Greenwald G. S.
Published: February 2005

Hypophysectomized female hamsters primed with 30 i.u. pregnant mare serum gonadotropin (PMSG) were injected with anti‐PMSG serum 72 h later to induce atresia in Graafian follicles. The earliest histological evidence of atresia was seen in the cumulus oophorus at 4 h with a significant increase in pyknotic nuclei. The mural granulosa cells, however, did not show pyknoses until 12 h following anti‐PMSG serum. The highest number of pyknotic nuclei in the cumulus oophorus was seen at 24 h, when pseudomaturation of the oocyte occurred. Breakdown of the mural granulosa cells was greatest by 48 h. Morphometric measurements of the follicles showed a significant decline in the thickness and area by the granulosa layer at 48 h following injection of anti‐PMSG serum.

The thecal compartment showed a decline in number of mitoses at 4 h and 12 h and in area at 48 h. However, no pyknotic thecal cells were observed during the 72 h following injection of anti‐PMSG serum. The results support previous work using this model, which showed major biochemical changes in the granulosa cells at 12 and 48 h. The theca, however, was comparatively unaffected during atresia. The various studies using this model shew changes in atretic follicles similar to those seen in other models and in the intact animal. The major advantage of this medel is that it produces a large synchronous population of follicles that rapidly becomes atretic.
Functional gap junctions in mouse small intestinal crypts
Authors: Bjerknes Matthew , Cheng Hazel , Erlandsen Stanley
Published: February 2005

We demonstrate intercellular transfer of Lucifer yellow and the existence of gap junctions in isolated mouse small intestinal crypts. The pattern of dye transfer approximates the normal pattern of cell proliferation and differentiation in the intestinal epithelium. These findings indicate that the cells of normal crypts form an effective intercellular continuum. This intercellular route may function in the establishment of chemical, ionic, or electrical fields, which in turn may play a role in the control of cell proliferation, differentiation, and secretion in the crypt.
Macrophage‐like cells in the muscularis externa of mouse small intestine
Authors: Mikkelsen H. B. , Thuneberg L. , Rumessen J. J. , Thorball N.
Published: February 2005

In muscularis externa of mouse small intestine, cells with ultrastructural features of macrophages were invariably observed in three layers: in the subserosal layer, between the circular and longitudinal muscle layers, and in association with the deep circular plexus. These macrophage‐like cells (MLC) had a single indented nucleus, perinuclear Golgi complex, smooth and rough endoplasmic reticulum, many pits (coated and uncoated) in the plasma membrane, coated vesicles, light vesicles, and primary lysosomes, but rather few heterogeneous lysosomal vacuoles. MLC were partially enveloped by processes of interstitial cells of Cajal.

FITC‐dextran used in combined fluorescence stereo microscopy, fluorescence microscopy, and electron microscopy was employed as a tracer to study the endocytic qualities of the MLC. The mice were killed 5, 15, 30, and 60 min, 1 day, and 4 days after dextran administration. By fluorescence microscopy after 1 or 4 days MLC were observed as a constant cellular population with a strikingly regular distribution. By electron microscopy dextran‐containing vacuoles were conspicuous after 1 h or more. MLC of the subserosal layer and between the circular and longitudinal muscle layers could be distinguished with respect to general appearance, pattern formation, and apparent dextran contents.
Movements at the carpometacarpal and metacarpophalangeal joints of the hand and their effect on the dimensions of the articular ends of the metacarpal bones
Authors: Batmanabane Mounissamy , Malathi Srivatsan
Published: February 2005

A detailed study was undertaken to quantify the range of various movements at the carpometacarpal and metacarpophalangeal joints of the hand in cadavers and compare the values so obtained with those in the living, measured with the help of skiagrams. Longitudinal sections of hand were also prepared to bring out the nature of articulations at the carpometacarpal joints. Based on the data available, metacarpal mobility formulae of 1 > 5 > 4 > 2 > 3 for the carpometacarpal, and 5 > 4 > 3 > 2 > 1 and 5 > 2 > 4 > 3 > 1 for metacarpophalangeal joints are being proposed with the hope that these formulae will find their application in the clinical practice to assess the extent of functional damage to these joints as well as to evaluate the rate of progress or deterioration, in course of time. As an extension of our earlier study (Batmanabane, 1982), osteometric analysis of the metacarpus was also carried out and it is confirmed that it is the mobility which determines the osteometric features of the articular ends of these miniature long bones.
Functional units in rainbow trout (Salmo gairdneri) liver: I. Arrangement and histochemical properties of hepatocytes
Authors: Hampton James A. , McCuskey Patricia A. , McCuskey Robert S. , Hinton David E.
Published: February 2005

The architectural arrangement and selected histochemical properties of hepatocytes in the rainbow trout (Salmo gairdneri Richardson) were examined. Light and transmission electron microscopic (TEM) examination following fixation by portal venous perfusion revealed a tubular arrangement of hepatocytes. Lobules, as defined in the adult mammal, were absent. Billary epithelial cells associated with bile preductules and ductules were a prominent feature of trout liver. Patterns and location of reaction products for glucose‐6‐phosphatase (G‐6‐Pase), glucose‐6‐phosphate dehydrogenase (G‐6‐PDH), and magnesium‐dependent adenosine triphosphatase (ATPase), enzymes preferentially distributed in mammalian liver, were demonstrated in trout liver. A slightly heavier staining pattern for G‐6‐Pase was seen around presumptive portal venules but all other enzyme reaction patterns were uniform throughout the liver parenchyma. Following ATPase localization, four sizes of biliary passageways (canaliculi, bile preductules, ductules, and ducts) were visualized. Maximum glycogen retention was achieved with freezedrying and glycolmethacrylate embedding and with this method intense, uniform glycogen staining was observed in all areas of the liver. Companion TEM examinations revealed large depots of glycogen within hepatocytes. The results are important for interpretation and description of the effects of toxic/carcinogenic alteration on trout liver.
The bat pituitary cleft: Phasic production and release of secretory granules by microvillous cells
Authors: Nunez Eladio A. , Payette Robert , Gershon Michael D.
Published: February 2005

The ultrastructure of the two types of cells, ciliated and microvillous, lining the wall of the bat pituitary cleft was examined at different periods during the annual life cycle. Ciliated lining cells remained unchanged in structure throughout the yearly activity cycle. In contrast, microvillous lining cells exhibited striking cyclic morphological changes. Throughout the active phase of the life cycle and during most of the hibernating period, the structure of microvillous cells is unchanged. However, toward the end of hibernation, the cells produce and store large numbers of round to ovoid dense secretory granules. Just prior to arousal, the microvillous cells are packed with secretory granules. At arousal, the cells undergo marked degranulation; the granules appear to be discharged into the lumen of the cleft. Degranulation is followed by a period of proliferation of rough endoplasmic reticulum, the cavity of which is often filled with large paracrystalline inclusions. Within 1 month, microvillous cells return to a resting state and are devoid of secretory granules.
Equine bone marrow: A quantitative analysis of erythroid maturation
Authors: Tablin Fern , Weiss Leon
Published: February 2005

The equine bone marrow responds to blood loss by increased erythropoiesis, only releasing reticulocytes into the peripheral circulation in severe chronic anemia. We have used morphometric analysis based on electron microscopy of the equine marrow to examine the maturation and release of reticulocytes. Developing red cells in the bone marrows of normal and chronically anemic horses were divided into four stages: early, intermediate, late‐stage erythroblasts, and reticulocytes. Morphometric analysis of each stage included volume density of mitochondria per μm3 of cytoplasm, surface area of the outer mitochondrial membrane per unit volume of mitochondria, and the number of ribosomes per unit volume of cytoplasm (total, clustered, single). Matched t tests between normal and anemic animals showed significant differences (P ⩽.001) for volume density of mitochondria and numbers of ribosomes only at the reticulocyte stage. The large reticulocyte produced and released in chronic anemia may be best explained by a skipped mitotic division.
Volumetric changes in the developing rabbit calvarium
Authors: Alberius Per , Selvik GÖRan
Published: February 2005

Tantalum bone markers were implanted in the frontal, parietal, and temporal bones, at least two in each bone segment, in seven male New Zealand white rabbits. Roentgen stereophotogrammetric analyses were performed for regular intervals between ages 30 to 142 days. With the exception of a few implants in the temporal bone, bone markers remained stable during the observation period. Volumetric and longitudinal growth data were compared. Calvarial polyhedron volumes increased linearly. Growth at the actual neurocranial sutures demonstrated an individually fluctuating pace. No obvious correlation between volumetric and longitudinal growth was noted. This might be explained by sagittal and temporal suture growth in periods being close to the methodological error and failure to document bone rotations. Previous observations on the linearity in cerebral weight increase during corresponding periods of time points to the decisive role of neural mass growth in calvarial development in rabbits. Suture growth characteristics are discussed.
The initiation of osteodentin formation in the rat incisor after adriamycin administration
Authors: Karim A. C.
Published: February 2005

In order to study the initiation of osteodentin formation in rat incisors, animals were injected intravenously with adriamycin (5 mg/kg body weight), and killed from 2 to 7 days after injection by perfusion with a 2.5% buffered glutaraldehyde solution. Control animals, injected with only physiological saline, were treated in the same manner.

Three days after adriamycin injection aggregations of mesenchymal cells were observed along the mesial and lateral walls of the pulp chamber. Between 3 days and 7 days osteodentin production was observed at the sites where the mesenchymal aggregations were previously observed. Electron microscopic observations revealed that the cells involved in the aggregates were larger and contained more profiles of rough endoplasmic reticulum and secretion granules than the unaffected pulp cells. The osteodentin matrix first appeared as a scant deposition of collagen fibers between the cells. As more collagen fibers were deposited the matrix became much denser. Some cells that initially formed the mesenchymal aggregates were completely enclosed by the increased deposition of the matrix.

It therefore appears that osteodentin formation, as observed in the rat incisor pulp after adriamycin administration, is the result of an abnormal differentiation of pulp mesenchymal cells.
Mast cell heterogeneity in dog skin
Authors: Becker Allan B. , Chung K. Fan , McDonald Donald M. , Lazarus Stephen C. , Frick Oscar L. , Gold Warren M.
Published: February 2005

The degree of metachromasia of mast cell granules is known to vary with the type of tissue fixation and among different tissues and species. The present study sought to determine whether mast cells in dog skin are heterogeneous with respect to fixation and staining properties. We performed skin biopsies in six anesthetized, atopic dogs and one mongrel dog. One biopsy was fixed in formalin and a second, from a parallel abdominal site, was fixed in basic lead acetate (Mota's solution). Adjacent sections from each biopsy were stained with alcian blue (1%, pH 0.5) or for chloroacetate esterase activity. In alcian blue‐stained sections, one‐third fewer mast cells were detected in skin fixed in formalin (1,836 ± 454 mast cells/mm3, mean ± SEM) than in skin fixed in basic lead acetate (2,684 ± 527 mast cells/mm3) (P < 0.05). The chloroacetate esterase reaction detected the larger number of mast cells regardless of the fixative used. We conclude that mast cell heterogeneity, as demonstrated by metachromatic staining following different types of tissue fixation, exists in dog skin. “Typical” mast cells stain with alcian blue regardless of fixation; however, “atypical” mast cells exhibit metachromasia only after fixation in basic lead acetate. Both the typical and atypical types of mast cells have chloroacetate esterase activity.
Ultrastructural visualization of intracellular porphyrin in the rat Harderian gland
Authors: Carriere R.
Published: February 2005

The Harderian glands of male Albino rats 1–24 months of age were studied by electron microscopy. In most glands, a few acinar cells contained straight and curved trilaminar profiles identical in form to the material in the luminal masses of porphyrin pigment. They resembled the structures which several investigators have identified as crystals of protoporphyrin IX in porphyric human and mouse hepatocytes. Protoporphyrin IX is the predominant form synthesized by rat Harderian cells in vitro. The trilaminar profiles were within the cytoplasm but not within the lipid secretory vacuoles.

A large number of the acinar cells had finely tubular endoplasmic reticulum (ER). However, cells containing the trilaminar forms consistently had dilated ER vesicles. This change may have been a prelude to cell death, for some pigment‐containing cells attached to the acinar basal lamina also displayed fragmented organelles and a loss of density of the cytoplasmic matrix. In some acinar lumina there was abundant cell debris along with the trilaminar profiles. It is concluded that in the rat, some of the Harderian free porphyrins can be released through cell death.
“Cholinergic” postsynaptic membranes of bullfrog sympathetic ganglia: Electron microscopy of thin sections and freeze‐fracture replicas
Authors: Watanabe Hiroshi , Washioka Hiroshi , Tonosaki Akira
Published: February 2005

“Cholinergic” synapses of the bullfrog sympathetic ganglion cells were investigated with thin sectioning, complementary freeze‐fracturing, and deepetching methods after glutaraldehyde fixation. The protoplasmic (‐fracture) face (PF) of the postsynaptic membrane was characterized by intramembranous particles (IMPs), 3,500/μm 2 in density, consisting of larger particles, 10–12 nm in diameter, and smaller ones, 8–9 nm; the complementary exoplasmic (‐fracture) face (EF) contained larger and smaller IMPs, 750/μm 2 in density, and numbers of pits.

By close inspection of the sections and freeze‐fracture replicas at high magnification and with deep‐etching in particular, it was concluded that aggregated IMPs might represent transmembranous components and that the particulate entities existing in the postsynaptic active zones might be larger in number than those exposed to view and counted here in the “cholinergic” synapses. An individual IMP often appeared to consist of five or six subunits arranged in a rosette with a central pit.

These findings suggest that the aggregated IMPs, particularly the larger ones, may be closely related to the structure of the nicotinic ACh receptor‐ion channel complex.
Microanatomy of the renicule of Balaena mysticetus
Authors: Henk William G. , Abdelbaki Yahya Z. , Haldiman Jerrold T. , Albert Thomas F.
Published: February 2005

Renicules from twelve bowhead whales (Balaena mysticetus) were examined utilizing light, scanning electron, and transmission electron microscopes. The basic organization of the renicule into capsule, cortex, sporta perimedullaris, medulla, and calyx is described. Despite less than perfect preservation resulting from environmental and logistical conditions at the collecting sites, it has been possible to document the basic microstructure of most components of the renicule of this endangered species. Several unusual features were observed. The absence of smooth muscle fibers (other than in vessel walls) from the capsule, sporta perimedullaris, and calyx wall is a departure from what is reported in other cetaceans as is the consistent presence of arcuate arteries in the substance of the sporta perimedullaris. Large subcapsular veins are present but do not appear to represent connecting elements in an alternative venous return through capsular and interrenicular veins. Elastic fibers are seen only in the sporta perimedullaris and the calyx wall, whereas reticular fibers are most abundant in the medullary stroma. Finally, enlarged cells with clear cytoplasm are seen in the tunica media of the glomerular afferent arterioles extending a variable, but always considerable, distance toward the interlobular arteriole. These cells are presumed to represent an extended array of the epithelioid cells common in the afferent arterioles of the juxtaglomerular apparatus of other mammalian kidneys.
Reversibility of the structural effects of pressure overload hypertrophy of cat right ventricular myocardium
Authors: Marino Thomas A. , Brody Eric , Lauva Ines K. , Kent Robert L. , Cooper George
Published: February 2005

The purpose of the present quantitative structural study was to determine whether the histological alterations seen in pressure overloaded myocardium return to normal, as in vitro contractile function does, upon removal of the pressure overload stimulus. Three experimental groups of four cats each were studied: a group with pulmonary artery banding to create a pressure overload, a group that had been subjected to an equivalent duration of pressure overload and then had that pressure overload removed, and a group of sham‐operated controls. Seven to 10 weeks after each operative procedure, the right ventricular pressure was elevated only in the pulmonary artery‐banded group. The right ventricle/body weight ratio was significantly increased in the pressure overloaded group only. The body weight at sacrifice, the left ventricle/body weight ratio, and the right ventricular end‐diastolic pressure did not differ significantly in the three groups. The striking histological changes in the right ventricular myocardium hypertrophying in response to a pressure overload were the decrease in the volume density of cardiocytes and the increase in connective tissue in papillary muscles. These were reversed when the pressure overload was removed. This study demonstrates that when a pressure overload is removed, myocardial structure returns to normal as the function returns to normal. Given the critical importance of the proportion of cardiocytes and connective tissue components to both systolic and diastolic cardiac function, these data support the hypothesis that the abnormal proportions of these structures provide a potential morphological basis for at least some of the functional abnormalities observed in pressure overload hypertrophy of the cat right ventricle.
Subcellular distribution of the nonspecific esterase in the mouse epididymis with special reference to regional differences
Authors: Fain‐Maurel Marcelle‐Anne , Abou‐Haïla Aïuda
Published: February 2005

The subcellular distribution of esterases was studied in mouse epididymis by using 5‐bromo‐indoxyl‐acetate as a substrate. In all the cells of the duct, a low level of esterase activity was detected except in one of the five segments of the head–segment IV; in one of the three types of apical cells–the “prominent cells”; and in the “clear cells” scattered in the middle and distal parts. In these cells, the intensity of the reaction was high.

The reaction product was consistently found in the endoplasmic reticulum and was more abundant in cells showing a high level of activity than in others. In cells with low esterase activity, the reaction was mainly restricted to this organelle. In highly active cells, the spectrum of subcellular locations was selectively enlarged and esterase was demonstrated in almost all cell compartments, including the cell membrane, nuclear envelope, mitochondria, lytic structures, and, more rarely in the Golgi apparatus or microvilli. These locations were dependent on cell type. A weak enzyme activity also appeared on mature spermatozoa.
Testicular descent in the rat and a comparison of this process in the rat with that in the pig
Authors: Wensing C. J. G.
Published: February 2005

Testicular descent in mammals with a saclike cremaster muscle and in those with a striplike cremaster muscle differs morphologically as well as topographically. In spite of this, functional interpretations are sometimes extrapolated from species to species without defining precisely the different structures involved in this process. This has resulted in several unnecessary conflicting opinions on the mechanism of testicular descent.

In this study the anatomical changes of the structures involved in the process of testicular descent in the rat are described and these data are compared with similar data on the pig. It appears that the major changes in the process in both species are (1) the outgrowth of gubernacular mesenchyme, (2) subsequent regression of this mesenchyme, and (3) development and growth of the cremaster muscle. If the structures involved are properly defined the homology of the changes in both species becomes evident.
Dividing type II cell in rabbit taste bud
Authors: Toyoshima Kuniaki , Tandler Bernard
Published: February 2005

Examination of rabbit foliate papillae by electron microscopy revealed for the first time the existence of a dividing cell within a taste bud. The ultrastructure of this cell was in keeping with that of type II cells of the sort located in the center of taste buds. Whether this cell is capable of differentiating into other cell types is still unclear.
Development of hamster tracheal epithelium: IV. Cell proliferation and cytodifferentiation in the neonate
Authors: Otani Elaine M. , Newkirk Carnell , McDowell Elizabeth M.
Published: February 2005

The development of the tracheal epithelium was studied in neonatal hamsters beginning on the day of birth (day 1) and ending on day 8. Morphological changes were characterized and the proportions of cells (basal, secretory, ciliated) and mitotic indices were quantified along dorsal and ventral epithelial surfaces. Cellular proportions were stable throughout the week but the makeup of the dorsal and ventral epithelia was different. The ventral epithelium was composed of about 59% secretory cells, 39% basal cells, and 2% ciliated cells, whereas the dorsal epithelium was composed of about 52% secretory cells, 32% basal cells, and 16% ciliated cells. Mitotic indices were generally less than 1% and mitotic activity in secretory cells predominated proportionate to the ratios of secretory cells and basal cells in dorsal and ventral epithelia. During the first postnatal week changes occurred that were related to the maturation of basal cells and secretory cells. Glycogen was rapidly lost from both cell types during the first part of the week and the lateral cell membranes became increasingly complex. Apical microvilli had formed in the secretory cells by day 2 and hemidesmosomes were well developed in the basal cells. Rough and smooth endoplasmic reticulum membranes developed rapidly in the secretory cells, and mucous granules were abundant in some cells on days 4—8, especially in the ventral epithelium between the cartilage rings.

The study shows that shifts in the proportions of basal, secretory, and ciliated cells do not occur in dorsal or ventral tracheal epithelium during the first postnatal week but the basal cells and secretory cells undergo rapid cytodifferentiation and functional maturation at this time.
Mechanoreceptors in the human anterior cruciate ligament
Authors: Zimny Marilyn L. , Schutte Michael , Dabezies Eugene
Published: February 2005

This study was undertaken to identify and quantitate mechanoreceptors in the human anterior cruciate ligament (ACL). Ligaments from six human subjects were obtained at autopsy, cut into cross‐sectional segments 1.0–1.5 cm thick, and kept oriented as to the femoral and tibial attachments. The segments were stained in bulk by using a modified gold chloride method, frozen, and sectioned on a sliding microtome at 100 μm. The sections were floated in alcoholic gelatin, mounted on slides, dehydrated, and coverslipped. Serial sections were studied with the light microscope and receptors were photographed. Cross‐sectional maps of every tenth section were made outlining the periphery of the ACL and the receptors within that section. With these maps, a computerized, morphometric analysis of the ACL was done, thus obtaining the percentage of receptors in each section and in each ACL. In addition to free nerve endings, two morphologically distinct mechanoreceptors were identified: (1) Ruffini end organs and (2) Pacinian corpuscles. Preliminary morphometric analyses show that populations of mechanoreceptors are greater at the femoral and tibial ends of the ligament and constitute approximately 2.5% of the ligament. Based on these findings the human ACL has the anatomic basis for a discriminating afferent outflow to the central nervous system.
A new approach to quantification of sertoli cells that avoids problems associated with the irregular nuclear surface
Authors: Johnson Larry
Published: February 2005

A new approach to quantification of Sertoli cells is described. The number of Sertoli cells per testis was calculated from the number of spermatids per testis, the number of spermatids per Sertoli cell apex, and the correction for the lifespan of spermatids enumerated per testis. To evaluate this method under different physiological conditions, testes from 28 adult (4–20‐year) stallions obtained in the nonbreeding season (December–January) and from 28 adult stallions in the breeding season (June–July) were compared. Number of Sertoli cells per gram parenchyma was similar between seasons. However, the number of Sertoli cells per testis was significantly greater in the breeding season. In verification of this method, the number of spermatids per Sertoli cell apex was similar to that calculated as the ratio of spermatids to Sertoli cell in the same stallions. Likewise, absolute values similar to those of other approaches further verify the validity of this approach.
Effects of denervation and delayed amputation on forelimb regeneration in Xenopus laevis froglets
Authors: McLaughlin Danielle S. , Liversage Richard A.
Published: February 2005

Left forelimbs of postmetamorphic Xenopus laevis froglets were repeatedly denervated prior to and following amputation. Amputations were performed 14, 21, 28, or 42 days after the original denervation. A tissue‐regenerative response resulting in the formation of a spike‐shaped, heteromorphic outgrowth was found in the sham‐denervated and control animals, but dedifferentiation of the stump tissues was not apparent. Tissue‐regenerative outgrowths were not observed in the denervated cases; instead, dermal wound healing and stump and scar formation occurred. In both control and experimental cases, however, a periosteal proliferative response to amputation injury led to the development of a greatly thickened periosteum the length of the amputated radius‐ulna as well as a cap of cartilage at the distal end of these bones. We conclude from these results that forelimbs of postmetamorphic froglets are incapable of adjusting to a prolonged nerveless state sufficient to allow the normal tissue‐regenerative response of spike outgrowth formation.
Neuropeptide tyrosine (NPY)‐like immunoreactivity in adrenal chromaffin cells and intraadrenal nerve fibers of rats
Authors: Kuramoto Hirofumi , Kondo Hisatake , Fujita Tsuneo
Published: February 2005

The present peroxidase‐antiperoxidase immunohistochemical study demonstrated that approximately 50% of the total chromaffin cells of the rat adrenal medulla exhibited NPY‐like immunoreactivity. The immunoreactive material was localized in the core of the chromaffin granules as well as diffusely in the cytoplasm. By combination of immunohistochemistry with noradrenaline‐fluorescence microscopy, all NPY‐immunoreactive chromaffin cells are nonfluorescent, indicating that all NPY‐chromaffin cells co‐store adrenaline. A comparison of two consecutive sections, each of which was processed for the immunostaining with anti‐NPY and anti‐Met‐Enk‐Arg‐Gly‐Leu antisera, respectively, indicated that NPY and preproenke‐phalin A and its derivatives coexist in approximately one‐fifth of the total NPY‐immunoreactive cells.

In addition to the NPY‐immunoreactive cells, a plexus of NPY‐immunoreactive nerve fibers with varicosities was found in the subcapsular regions of the adrenal gland. The nerve fibers were often associated with small blood vessels and extended into the zona glomerulosa. Single NPY‐immunoreactive fibers were sparsely distributed in the deeper regions of the cortex and in the medulla. Ganglion cells in the adrenal gland were not seen exhibiting intensely positive NPY‐like immunoreactivity. The NPY‐immunoreactive nerve fibers contained abundant small clear vesicles mixed with a few small and large granular vesicles. The immunoreactive material appeared on the granular cores as well as in the axoplasm. The NPY fibers were closely apposed to smooth muscle cells and pericytes of small blood vessels in the cortex. They were sometimes seen in close apposition to the fenestrated endothelial cells with a common basal lamina intervening. The NPY fibers also made synaptic contacts with both cortical and chromaffin cells.
Immunohistochemical localization of the MHS‐5 antigen in principal cells of human seminal vesicle epithelium
Authors: Evans Robert J. , Herr John C.
Published: February 2005

The location of the antigen recognized by monoclonal antibody MHS‐5 in the human reproductive tract was examined by means of enzyme‐linked immunosorbant assay (ELISA) and indirect immunohistochemistry employing the strepavidin‐biotin‐complex method. Homogenates of male reproductive tract tissues and other human organs assayed by ELISA demonstrated immunoreactivity of the MHS‐5 monoclonal antibody specifically with human seminal vesicle extracts. Varying ratios of seminal protein and monoclonal antibody ascites were tested to determine the amount of antigen necessary to completely absorb the antibody in the ELISA assay. This ratio was subsequently used to obtain the absorbed negative control for histochemical localization studies. By light microscope examination of seminal vesicle tissue in paraffin section, the MHS‐5 antigen was localized in principal cells of the seminal vesicle epithelium. Epididymal sperm, obtained from patients at orchiectomy and vasovasostomy were found to lack the MHS‐5 antigen. Following incubation with seminal protein or fluid obtained from the lumen of the human seminal vesicle, epididymal sperm reacted with the MHS‐5 antibody on ELISA. These findings indicate that the MHS‐5 antigen, a novel protein previously shown to be a unique marker for human semen, is a secretory product of the human seminal vesicle epithelium and may be reconstituted on the surface of epididymal spermatozoa.
A morphometric comparison of the nasopharyngeal airway of laboratory animals and humans
Authors: Patra A. L. , Gooya A. , Ménache M. G.
Published: February 2005

Solid silicone rubber casts of the nasopharyngeal and laryngeal regions of a human cadaver (child, 3 years old) and a laboratory primate (baboon, 10 years old) were made, and cross‐sectional areas were measured in detail. Cross‐sectional areas of other species reported in the published literature were used for comparison. In the child's nose cast, the frontal nasal duct (frontonasal duct), which enters the anterior part of the middle meatus, and the sphenoidal recess were almost absent. The ethmoidal turbinates (superior and middle concha) and the maxillary turbinates (inferior concha) were present but were not fully developed. In the baboon nose, the different turbinates were well defined and smooth but of a less complex nature than the child's nose. Of the species compared, the baboon's upper airways had the greatest similarity to the human child's. The present study shows that for the species investigated and for those from the literature, the cross‐sectional area increases from the external nares to the maxilloturbinate region (inferior concha). There is a relatively sudden drop in cross‐sectional area about halfway through the nose. The present study suggests a functional relationship between nasal structure and cross‐sectional area across species.
Colocalization of luteinizing hormone and serotonin in secretory granules of mammalian gonadotrophs
Authors: Payette Robert F. , Gershon Michael D. , Nunez Eladio A.
Published: February 2005

Previous studies have demonstrated the uptake of exogenous and storage of endogenous 5‐hydroxytryptamine (5‐HT) in parenchymal cells of the anterior pituitary. The present experiments were undertaken to test the hypothesis that the endogenous 5‐HT of the anterior lobe of the pituitary is costored with β‐luteinizing hormone (β‐LH) within the same secretory granules of gonadotrophs. Electron microscope immunocytochemistry was used to detect 5‐HT and β‐LH immunoreactivities in the anterior pituitary glands of mice and bats. Primary antisera generated in different species of animals to these two antigens were localized with appropriate species‐specific secondary antisera coupled to colloidal gold particles of different sizes. This enabled 5‐HT and β‐LH immunoreactivities to be demonstrated simultaneously on ultrathin sections of fixed anterior lobe tissue mounted on electron microscope (EM) grids. In both bats and mice 5‐HT immunoreactivity, identified by immunostaining of β‐LH, was found in gonadotrophs, and in no other cell type. Within gonadotrophs about 25% of the secretory granules were labeled by antisera to both 5‐HT and β‐LH, although 100% of granules reacted with the antiserum to B‐LH. No secretory granules were found that were immunostained only by the antiserum to 5‐HT. It is concluded that endogenous 5‐HT may be a normal constituent of mammalian gonadotrophs and that it is colocalized with β‐LH in at least a subset of the secretory granules of these cells. It cannot yet be concluded that gonadotrophs synthesize 5‐HT as well as taking it up from the ambient medium. The function of 5‐HT in the pituitary remains unknown; however, the costorage of 5‐HT and β‐LH in the same secretory granules would seem to be a mechanism to ensure the simultaneous release of the two substances by exocytosis.
A microcomputer‐based graphical reconstruction technique for serial sectioned objects, with hidden line removal
Authors: Berghe W. Vanden , Aerts Peter , Claeys H. , Verraes W.
Published: February 2005

The presented software package fulfills the need for processing serial sections with a microcomputer configuration, enabling three‐dimensional reconstruction with hidden line removal. The language used is an interpreted BASIC‐dialect (HPL). The input is performed via an interactive program. The object can be rotated in space. The Hidden Line algorithm does not depend upon a raster technique. Points of intersection of successive contours are calculated and inserted, thus providing drawings of high resolution and quality. The handling time can be said to be short, especially when considering the capacities of the microcomputer configuration used.
Integration of clinical problems in teaching gross anatomy: Living anatomy, X‐ray anatomy, patient presentations, and films depicting clinical problems
Authors: Pabst Reinhard , Westermann Jürgen , Lippert Herbert
Published: February 2005

In addition to lectures and the dissection course, four supplements are described to stimulate first‐year medical students to learn gross anatomy. All topics are coordinated with the dissection course. The additional options are living anatomy, X‐ray anatomy by a roentgenologist, presentation of patients by clinicians, and films on clinical problems. This integrated curriculum of basic and applied anatomy generates a high level of student interest in gross anatomy.
Immunocytochemical study on fibrous sheath formation in mouse spermiogenesis using a monoclonal antibody
Authors: Sakai Yasuhiro , Koyama Yoh‐Ichi , Fujimoto Hirokazu , Nakamoto Tadashi , Yamashina Shohei
Published: February 2005

One of the components of the fibrous sheath was localized in the spermatids by the immunocytochemical method using the monoclonal antibody, K32, against the fibrous sheath of mouse mature epididymal sperm. The K32 immunoreaction was first detected in the cytoplasm of spermatids at stage 14 and appeared to increase in intensity at stage 15. At this stage, the framework structure of the fibrous sheath was formed completely in the tail, but the positive reaction in the fibrous sheath was observed only in the proximal portion of the principal piece. This change in the antigenicity of the fibrous sheath proceeded in a proximal to distal direction, which was opposite to the mode of formation of the framework structure in the fibrous sheath. Finally, the entire fibrous sheath strongly reacted to the K32 antibody at stage 16, while the reaction in the cytoplasm ceased to occur.

These observations indicate that the fibrous sheath matures with immunologically detectable changes in its components following formation of the framework structure. In consideration of the retrograde progression of the cytoplasmic reaction, the fibrous sheath components may possibly be transported from the spermatid cytoplasm into the principal piece.
Ultrastructural changes in hamster lung 15 min to 3 hr after exposure to pancreatic elastase
Authors: Morris Shirley M. , Kagan Herbert M. , Stone Phillip J. , Snider Gordon L. , Albright John T.
Published: February 2005

A single endotracheal instillation of porcine pancreatic elastase into hamster lungs induces morphological changes that can be detected as early as 15 min after the instillation of enzyme. Lung tissue from animals sacrificed at six time points between 15 min and 3 hr after enzyme instillation was examined for ultrastructural alterations. There were few of these alterations and they were highly focal, but they included damaged epithelial cells and partially digested elastic fibers that occurred both in the parenchyma and the pleura.

A cytochemical technique employing N‐t‐Boc‐L‐alanine‐p‐nitrothiophenyl ester as a substrate for elastase‐like enzymes was also used in an effort to locate pancreatic elastase shortly after instillation into the lungs. Reaction product was observed on the alveolar surface and in pinocytotic vesicles of alveolar type I cells, in connective tissue areas, in fibroblasts, and in pinocytotic vesicles of capillary endothelial cells. The location of reaction product coupled with ultrastructural alterations in the tissue suggests that pancreatic elastase instilled into the trachea may reach the interstitium in two ways: First, transport may take place across intact alveolar type I cells via pinocytotic vesicles, and second, a small amount of enzyme may gain access to the connective tissue after the disruption of epithelium in a few highly focal areas.