bluuebunny/crossref_metadata_2025_split huggingface dataset:
Light microscopic immunocytochemical study of fibrous sheath and outer dense fiber formation in the rat spermatid
Authors: Oko Richard , Clermont Yves 
Published: February 2005

AbstractThe formation of the fibrous sheath (FS) and outer dense fibers (ODF), two major cytoskeletal components of the tail of spermatozoa, was analyzed in the seminiferous epithelium by immunoperoxidase techniques applied to paraffin‐embedded testicular sections. Antibodies were prepared from purified FS and ODF fractions and from major 75 and 14.4 kDa FS polypeptides and major 32‐26 14.4 kDa ODF polypeptides. The immunostaining results showed that the production of FS and ODF proteins appeared to be exclusive to step 9‐19 spermatids and lasted over the duration of a full cycle of the seminiferous epithelium, or 12.8 days. During this period there was seemingly an initial lag of short duration between the synthesis and assembly of FS and ODF proteins followed by a long process of coordinated activity. Peak cytoplasmic immunoreactivity was reached in step 15 for FS proteins and midstep 16 for ODF proteins and and remained elevated thereafter for approximately 80 hr for both FS and ODF proteins. The immunoreactivity was more uniform and diffused for FS proteins and granulated or clumpy for ODF proteins. Assembly of FS proteins along the axoneme proceeded in a distal to proximal direction while for ODF proteins assembly proceeded in a proximal to distal direction. The main route of elimination of residual cytoplasmic FS and ODF proteins appeared to take place through the cytoplasmic droplets and residual bodies, respectively. There appeared to be no variation in step reactivity between the major ODF polypeptides tested and only minor variation in step reactivity between the major FS polypeptides tested. However, although the 14.4 kDa polypeptides of FS and ODF share antigenic determinants, they do not appear to be identical, because they presented different immunolocalizations during spermiogenesis and different directions of assembly along the axoneme.
Phagocytosis of collagen by mouse decidual cells
Authors: Zorn Telma M. T. , Tania Bijovsky A. , Bevilacqua Estela M. A. F. , Abrahamsohn P. A. 
Published: February 2005

AbstractCollagen fibrils were present within membrane‐bound vacuoles in the cytoplasm of mouse‐decidual cells on the 7th day of pregnancy. The space between the vacuole membranes and the fibrils was narrow and frequently filled with a granular electron‐dense material. The loss of banding of the collagen fibrils, their association with lysosomelike bodies, and the demonstration of acid phosphatase activity in the vacuoles indicate that the fibrils were internalized by the decidual cells and were being digested. It is suggested that phagocytosis of collagen is a mechanism of remodeling of the mouse decidua.
Study of the functional anatomy of bovine cervical mucosa with special reference to mucus secretion and sperm transport
Authors: June Mullins K. , Saacke R. G. 
Published: February 2005

AbstractThe bovine cervical mucosa was investigated with respect to structure, mucus secretory pattern, and sperm transport. Structural investigation included stereomicroscopic examination of surface‐stained tissue blocks and graphic reconstruction of serial sections by using both computer‐generated and Plexiglas models. Histochemistry of the mucosa was evaluated in follicular‐and luteal‐phase animals. Alcian blue, periodic acid Schiff, and high‐iron diamine were utilized to distinguish sialomucins, sulfomucins, and neutral mucins. Location and orientation of cervical sperm in follicular phase animals were evaluated 12 h postmating by using light and electron microscopy. Cervical mucosa was characterized by longitudinal primary folds, most of which maintained continuity throughout the cervix. Superimposed on these were secondary folds which varied in length and depth. Abundant, shallow, uniformly spaced, and parallel longitudinal “grooves” covered all surfaces. Grooves had greater continuity in regions distal, as opposed to proximal, to the cervical canal. Blind‐ending glands or crypts were not apparent. Follicular‐stage cervices exhibited a pronounced sialomucin production in basal areas within grooves while neutral and sulfomucins were predominant in apical areas. In luteal‐phase animals, basal sialomicin production was markedly decreased while sulfated and neutral mucins remained abundant. Numerous cranially oriented spermatozoa were observed within the shallow grooves of cervical folds (sialomucin‐rich areas) in mated animals and were unidirectionally opposed to ciliary beat. It appeared that privileged paths for transport of viable spermatozoa may originate in the fornix vagina, extend through longitudinal primary folds at the external os, and progress to the uterus within continuous sialomucin‐rich channels which are associated with basal areas of the shallow grooves, distal to the cervical canal.
Long‐term effects of gustatory neurectomy on fungiform papillae in the young rat
Authors: Ganchrow Judith R. , Ganchrow Donald 
Published: February 2005

AbstractRecent evidence from mature hamster fungiform papillae indicates that following denervation taste buds are present from 21 to 330 days in the absence of discernible intragemmal nerve fibers. In contrast, most prior taste bud degeneration studies focused on shorter survival times. The present inquiry in young rats examined the issue of postneurectomy buds, in which regeneration of the resected chorda tympani or facial nerves was prevented and anterior tongue tissue examined over a range of relatively long survival times (30–90 days). Conditions for observing potential taste buds used three histologic stains and a definition of the taste bud not necessarily requiring pore identification.In each case, serial section examination of the anterior‐most 2–3 mm of lingual epithelium revealed 29–56 bud‐containing fungiform papillae on the unoperated side. In contrast, ipsilateral to the neurectomy, only zero‐7 medially‐placed, mature‐looking buds were observed per case, as well as zero‐3 more laterally situated fungiform papillae containing small clusters of cells in basal epithelium that lacked the vertical organization and cytoplasmic staining intensity of mature taste buds. These cell aggregates were distributed evenly across survival time and stain used.Therefore, in young rats following gustatory neurectomy, longer survival times, per se, would not appear to be a prerequisite for sustaining fungiform taste buds. The appearance of “midline” buds postsurgery may be attributed to either normal contralateral or a net bilateral innervation, and/or ipsilateral denervation and bud loss inducing neural sprouting from the contralateral side.
Immunohistochemical evidence for the presence of neuropeptides in the hypothalamic suprachiasmatic nucleus of ground squirrels
Authors: Reuss Stefan , Hurlbut Edward C. , Speh Joan C. , Moore Robert Y. 
Published: February 2005

AbstractThe cytoarchitecture and immunocytochemical distribution of neuropeptides (corticotropin‐releasing factor, CRF; neuropeptide Y, NPY; oxytocin, OXY; vasopressin, VP; and vasoactive intestinal polypeptide, VIP) were studied in the hypothalamic suprachiasmatic nuclei (SCN) in male and female ground squirrels of two species (Spermophilus tridecemlineatus and S. richardsonii).Immunoreactive (IR) perikarya were found in sections incubated with VP or VIP antisera. VP‐IR cell bodies were seen in the dorsal and medial parts of the nucleus in colchicine‐treated animals. IR fibers were distributed thoughout the SCN. In the ventral part of the nucleus, VIP‐IR cells were seen in untreated animals and were more pronounced in colchicine‐treated animals. VIP‐IR fibers and terminals form a dense plexus throughout the nucleus. Furthermore, NPY‐IR terminals and fibers with multiple varicosities, but no IR perikarya, were present in the suprachiasmatic nuclei. Within the borders of the SCN, no cell bodies or fibers were stained with CRF or OXY antisera in any animal.
Epicardial development in the axolotl, ambystoma mexicanum
Authors: Fransen Margaret E. , Lemanski Larry F. 
Published: February 2005

AbstractRecent studies on avian and mammalian embryos have established that the epicardium is derived, not from the early heart tube, but from mesothelial tissue overlying the sinus venosus. We tested the validity of this concept for Amphibia by examining normal and cardiac lethal (c/c) mutant axolotl embryos (stages 35‐43) by electron microscopy.In axolotl embryos, the myocardial surface of the heart remains exposed to the pericardial fluid through stage 39. At this stage the transverse septum releases into the pericardial cavity mesothelial cells that subsequently flatten over the adjacent ventricular myocardium. However, mesothelial cells observed on the developing epicardium always appear rounded and may extend a filopodium up to 75 m̈m. This apparent “substrate‐dependent” difference in mesothelial cell shape may promote the extension of the epicardium over the rest of the myocardium. The initial site of epicardial formation persists in the adult as the ventricular pericardial stalk that connects the epicardium to the peritoneal lining of the transverse septum.Cardiac lethal (c/c) mutant embryos, despite the non‐contractility of their myocardia, form their epicardia in the same way. This suggests that the c/c mutation does not impair those properties of the myocardium that render it a suitable substrate for epicardial spreading. The abnormal pattern of epicardial coverage of the edematous stage 41 c/c mutant heart could be the result of its abnormally large myocardial surface area, the abnormal proximity of the atrium to the transverse septum, and/or the absence of heart contractions which could aid the dispersion of mesothelial cells within the pericardial cavity.Despite species differences, epicardial development in the axolotl is similar to the general pattern described for higher vertebrate embryos.
Morphometric study of the microvasculature of the main excretory duct subepithelia of the rat parotid, submandibular and sublingual salivary glands
Authors: Sato Atsuko , Miyoshi Sakuichiro 
Published: February 2005

AbstractThis study investigated the relationship between the fine structure of the main excretory duct (MED) epithelia and the subepithelial capillaries of the major salivary glands (parotid, submandibular, and sublingual) in the rat. The MED subepithelial capillaries vary in type (fenestrated and continuous), number of fenestrae present in the available fenestrated endothelium (the attenuated area of endothelium), and number of capillaries per unit length of epithelium.In the parotid gland, continuous capillaries predominate, and the capillary density per 200 μm of epithelium (1.73 in region I and 1.03 in region II) is lower than in the other two glands, as is the number of fenestrae per 10 μm of available endothelium (1.97 in region I and 1.25 in region II). The submandibular gland has mainly fenestrated capillaries. The capillary density per 200 μm of epithelium (4.46 in region I and 5.51 in region II) is higher than in the other two glands, as is the number of fenestrae per 10 μm of available endothelium (4.82 in region I and 7.90 in region II). Similarly, in the sublingual gland, fenestrated capillaries are dominant. The density of capillaries per 200 μm of epithelium (4.15 in region I and 4.31 in region II) is intermediate between the parotid and submandibular glands, as is the number of fenestrae per 10 μm of available endothelium (2.98 in region I and 3.83 in region II).
Distribution of serotonin‐immunoreactive cells around arteries arising from the common carotid artery in the chicken
Authors: Kameda Yoko 
Published: February 2005

AbstractBy using an immunoperoxidase method with antiserotonin antiserum, the distribution of serotonin‐immunoreactive cells in the carotid body region was investigated in chickens. The thyroid gland, cranial and caudal parathyroid glands, carotid body, and ultimobranchial gland of chickens were located along the common carotid artery as a continuous series and were supplied with branches arising from the artery. Almost all chief cells of the chick carotid bodies were immunoreactive for serotonin. Furthermore, numerous serotonin‐immunoreactive cells were widely distributed in the adventitial connective tissue around those arteries that issued from the common carotid artery to supply each endocrine organ, i.e., the carotid body artery, the esophagotracheobronchial artery, the ascending esophageal artery, and the inferior thyroid artery. These arteries usually arose by one trunk from the lateral aspect of the middle portion of the common carotid artery. The serotonin cells were most numerous around the carotid body artery and were dispersed along the whole length of the artery. In addition, they were detected around the common trunk of each artery and the roots of the ascending esophageal artery, the inferior thyroid artery, and the esophagotracheobronchial artery. The serotonin cells were also distributed in the tunica media of the common carotid artery. In that place, they were concentrated around the origin of the common trunk of each artery and were scattered below the origin along the longitudinal axis and on the opposite side of the origin. The serotonin‐immunoreactive cells distributed around and in the arteries may be involved in the control of blood flow and may have chemoreceptive properties.
Bone lining (endosteal) cells and hematopoiesis: A light microscopic study of normal and pathologic human bone marrow in plastic‐embedded sections
Authors: Islam Anwarul , Glomski Chester , Henderson Edward S. 
Published: February 2005

AbstractHuman trabecular bone that encloses the bone marrow (BM) is covered by a single layer of thin, sometimes inconspicuous, flat, elongated (spindle‐shaped) endothelium‐like cells with a round or oval nucleus. These “bone lining” cells, or endosteal cells (EC), form a continuous membrane (endosteum) over the trabecular bone surfaces. In most cases, the composition and thickness of these cells do not vary unless the cells are in intimate contact with hematopoietic tissue. In that instance, they are seen as a single layer adjacent to hematopoietic tissue or as a zone of tightly packed or loosely arranged mononuclear (hematopoietic) cells, some apparently originating from the endosteum. In a reparative process, such as following BM harvest, during which bony trabeculae (BT) are mechanically fratured, these cells are seen giving rise to osteoprogenitor (osteoblasts and osteoclasts) cells. Occassionally, the EC appear similar to BM stromal cells (morphologically and by their association with collagen/reticulin fibers) and are best seen at or near the BT that are cut tangentially. Short processes extending from the EC towards the underlying osteocytes have also been observed, suggesting that a channel of communication exists between them and osteocytes. Our observations, coupled with the experimental findings of others (i.e., that hematopoietic stem cells are concentrated near the endosteum, that cells responsible for BM and stroma regeneration are derived from the endosteal layer, and that high concentrations of hematopoietic colony‐stimulating factors are produced there), indicate that, in addition to functioning as a simple membranous covering layer for BT, the endosteum helps to support osteocytes and maintains mineral homestasis. In addition, these cells contribute to the hematopoietic microenvironment and thereby play a role in regulating hematopoiesis. We also believe that the EC are reminiscent of embryonal‐stage, undifferentiated mesenchyme, which under appropriate regulatory influence, can modulate and transform into cells with hematopoietic potential, stromal cells and osteoprogenitor cells.
Tetracycline administration normalizes the structure and acid phosphatase activity of osteoclasts in streptozotocin‐induced diabetic rats
Authors: Kaneko Haruki , Sasaki Takahisa , Ramamurthy Nungavaram S. , Golub Lorne M. 
Published: February 2005

AbstractDiabetes induces osteopenia, which is characterized by a deficiency of osteoid and decreased activity of osteoblasts. We recently found that tetracyclines prevent the loss of osteoid and bone matrix and the degeneration of osteoblasts in diabetic rats by a mechanism independent of their antimicrobial efficacy. However, bone remodeling requires the activity of osteoclasts as well as osteoblasts. To determine the in vivo effects of tetracycline on osteoclasts in long bones, either a tetracycline (minocycline, TC) or its chemically modified non‐antibiotic analogue (CMT), 4‐de‐dimethylaminotetracycline, was administrated daily to streptozotocin‐induced diabetic rats by oral intubation. After 21 days, the rats were perfusion‐fixed with a mixture of formaldehyde and glutaraldehyde, and the humeri were dissected and processed for ultracytochemical demonstration of acid trimetaphosphatase (ACPase) activity. In untreated non‐diabetic (control) rats, the osteoclasts at the zone of provisional ossification exhibited abundant mitochondria and cisterns of rough endoplasmic reticulum (RER) throughout the cytoplasm, prominent stacks of Golgi membranes, and lysosomes in the perinuclear cytoplasm, and numerous various pale vacuoles in the cytoplasmic area adjacent to well‐developed ruffled border. Intense ACPase activity was observed in the Golgi saccules, lysosomes, pale vacuoles, and the extracellular canals of ruffled border. The reaction products were also noted along the resorbing bone surfaces associated with the osteoclast ruffled border. The osteoclasts in the untreated diabetic rats showed a cytoplasmic organization similar to that of the non‐diabetic control rats, but showed little or no ruffled border which was replaced by a broad clear zone in some of these cells. However, most of the osteoclasts on bone matrix in the diabetics were devoid of both a ruffled border and a clear zone. ACPase activity was detected in the osteoclast cytoplasm of diabetic rat, as in the controls, but to a much lesser extent along the broad clear zone facing the resorbing bone surfaces. The osteoclasts in TC‐treated diabetic rats possessed both a clear zone and a small ruffled border. However, in some cases, they lacked both structures reminiscent of the untreated diabetic cells. The osteoclasts of CMT‐treated diabetic rats exhibited structural and enzymatic features essentially identical to those of the non‐diabetic control rats. These results suggest that the diabetes‐induced osteopenia results, at least in part, from degeneration of osteoclasts (as well as atrophic osteoblasts) and that tetracyclines may be effective in preventing these abnormalities by a mechanism not dependent on the drugs' antimicrobial properties.
Composition of myofiber types in limb muscles of the house shrew (Suncus murinus): Lack of type I myofibers
Authors: Suzuki Atsushi 
Published: February 2005

AbstractPostural muscles have many type I myofibers, which reacted strongly for acid‐stable myosin ATPase and were unreactive for alkali‐stable myosin ATPase (Ariano et al., J. Histochem. Cytochem., 21:51–55, 1973; Armstrong et al., Am. J. Anat., 163:87–98, 1982; Smith et al., J. Neurophysiol., 40:503–513, 1977). House shrews (Suncus murinus) keep abducting their limbs in locomotion and hardly lift their trunk off the ground. The limb muscles of Suncus were examined by histochemical methods to determine whether the locomotory and postural behavior is related to the proportion of type I myofibers. The observation of whole cross sections from the triceps surae, flexor digitorum superficialis, quadriceps femoris, and caudally situated muscles in the thigh showed that all myofibers of these muscles were unreactive for acid‐stable myosin ATPase and strongly reactive for alkali‐stable myosin ATPase: Those were classified as type II myofibers. Type II myofibers showed a weak (type IIB), moderate (type IIAB), or strong (type IIA) reaction for NADH tetrazolium reductase. Part of type IIA myofibers reacted weakly to moderately for menadione‐linked glycerol‐3‐phosphate dehydrogenase (m‐GPD), which predominated in the soleus muscle. Type IIAB, type IIB, and the remainder of type IIA myofibers reacted strongly for m‐GPD. The limb muscles contained subtypes of type II myofibers but no type I myofibers. In Suncus murinus, type I myofibers specialized for a postural maintenance may not be required because all myofibers function exclusively for propulsion.
Developmental appearance and ultrastructural immunolocalization of a major 66 kDa phosphoprotein in embryonic and post‐natal chicken bone
Authors: McKee M. D. , Nanci A. , Landis W. J. , Gotoh Y. , Gerstenfeld L. C. , Glimcher M. J. 
Published: February 2005

AbstractBiochemical analyses and immunocytochemistry were used to examine the developmental appearance of a major ∽66 kDa bone phosphoprotein (66 kDa BPP) in the mid‐diaphyseal region of embryonic and post‐natal chicken tibiae in vivo. Total protein and O‐phosphoserine (Ser‐P) and O‐phosphothreonine (Thr‐P) content of 8‐, 12‐, and 18‐day embryonic, and 4‐wk post‐natal chicken tibiae were determined by amino acid analysis. Similar bone samples were carried through a wide variety of tissue‐processing regimes including different protocols for fixation, decalcification, dehydration, and embedding prior to electron microscopy. For immunocytochemistry, tissue sections were incubated with a polyclonal antibody raised in rabbits against 66 kDa BPP, and the antigen was revealed by the high‐resolution protein A‐gold technique. Amino acid analysis, Western blotting, and immunocytochemistry all showed the presence and increasing concentration of bone phosphoprotein with advancing developmental age. Immunogold labeling was observed over osteoblasts and mineral deposits throughout the bone with the most intense reaction occurring at the mineralization front in embryonic tibiae. Electron probe X‐ray microanalysis confirmed the association of 66 kDa BPP with mineral. The levels of phosphoprotein in the tissue were directly correlated with increasing degrees of mineralization. These observations are consistent with previous proposals suggesting that phosphoproteins may play a significant role in the calcification of bone matrix.