bluuebunny/crossref_metadata_2025 huggingface dataset:
Distribution of serotonin‐immunoreactive cells around arteries arising from the common carotid artery in the chicken
Authors: Kameda Yoko
Published: February 2005

By 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

Human 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

Diabetes 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

Postural 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

Biochemical 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.
Effects of advancing age on the central response of rat facial neurons to axotomy: Light microscope morphometry
Authors: Vaughan Deborah W.
Published: February 2005

Following axotomy, the regrowth of peripheral axons takes longer in older individuals than in young ones. The present study compares central responses of facial motor neurons to a crush injury of the facial nerve in 3‐month‐old and 15‐month‐old male rats sampled through 28 days post‐crush (dpc). Neuronal somata, nuclei, and nucleoli were measured in 30 μm brain stem sections within subdivisions of the facial nucleus that contain the cell bodies responsible for the movement of the vibrissae. The temporal patterns of change in the size of the three structures were interpreted with reference to the re‐establishment of functional connections, i.e., the return of voluntary vibrissae activity, which is delayed by 4 days in the older animals relative to the younger ones. There was no age‐related difference in the pattern of somal swelling and recovery, nor was there an age‐related difference in the response of nuclei and nucleoli to axotomy through 4 dpc. Both nuclei and nucleoli increased in size in animals of both age groups, but after 4 dpc in the older animals nuclear enlargement was prolonged and the nucleolar increases were less robust compared to the younger animals. The greatest age difference appeared with the re‐establishment of functional connections. In the 3‐month‐old animals, the resumption of whisker activity coincided with vigorous transient increases in the sizes of nuclei and nucleoli; in the 15‐month‐old animals, there was little nuclear response to functional recovery and a comparatively small increase in nuclear sizes. Given that signals from the periphery initiate central metabolic changes when the target is reached, this study suggests that the deteriorative effects of advancing may not simply reside in the neuron's decreased resiliency, but may reside in deficiencies in the signals derived from peripheral supporting cells, the target muscle, or in the reception of those signals.
Structural and immunohistochemical aspects of the postovulatory follicle in Japanese quail
Authors: Van Nassauw Luc , Callebaut Marc
Published: February 2005

In the present study, we searched for the presence of granulosa lipid spheres, of lacunae, and of the smooth‐muscle markers desmin and α‐smooth‐muscle actin, in the wall of the POF1 of the quail ovary. Lacunae, using the labelled yolk technique, were visible as large cavities in the POF1 wall. The immunohistochemical localization of desmin was similar to that observed in preovulatory follicles. A similar distribution was observed using an anti‐α‐smooth‐muscle actin antiserum, but the cells of the theca externa were also positively stained. The general conclusion was that the studied structures were similarly localized in the follicle wall, before and during the day after ovulation, but that they are more obvious in the POF, due to its general contracted state.
Functional and structural changes of rat plantaris motoneurons following compensatory hypertrophy of the muscle
Authors: Finkelstein David I. , Lang John G. , Luff Anthony R.
Published: February 2005

The conduction velocity and histological structure of motoneurons innervating normal and hypertrophied rat plantaris muscles were investigated. Hypertrophy was produced by ablation of synergist muscles. Single motor units were obtained by ventral root dissection and conduction velocities measured. The structure of neurons was investigated following retrograde labeling with horseradish peroxidase. A combined silver, gold and cholinesterase staining method was developed to study the motor endplate. In addition, the peripheral nerve was fixed, embedded in Araldite, and sectioned for determination of axonal size and myelin thickness. Conduction velocity of motor axons decreased following hypertrophy of the skeletal muscle (control CV = 75.8 ± 8.9 m s−1, n = 94, hypertrophy CV = 69.0 ± 12.3 m s−1, n = 84). However, no alteration in the size of motor axons or myelin thickness could account for this alteration in conduction velocity. Mean motoneuronal soma size decreased following muscle hypertrophy (soma diameter: control 36.1 ± 4.6 μ, n = 283, hypertrophy 32.9 ± 4.5 μ, n = 294). The complexity of the motor endplate increased following hypertrophy with an increased occurrence of nodal sprouts. In addition, the area of cholinesterase staining increased following hypertrophy (control 588.1 ± 297.2 μm2, n = 269, hypertrophy 857.7 ± 357.0 μm2, n = 269). This study found that both the morphological and physiological parameters of motoneurons innervating a hypertrophied muscle were shifted toward those of normal rat slow motor units.
Topography and morphology of retinal ganglion cells in Falconiforms: A study on predatory and carrion‐eating birds
Authors: Inzunza Oscar , Bravo Hermes , Smith Ricardo L. , Angel Manuel
Published: February 2005

The topographic distribution of retinal ganglion cells and their cell body size have been studied in five Falconiform species, including predatory (chilean eagle Buteo fuscenses australis, and sparrow hawk Falco sparverius) and carrion‐eating (chimango caracara Milvago chimango; condor Vultur gryphus, and black vulture Coragyps atratus) birds. All these species had a well defined nasal fovea and a horizontal streak. Instead of a temporal fovea as in eagles and hawks, an afoveate temporal area is present in chimango, condor, and vulture. The highest ganglion cell density was found in the nasal fovea of Falco and Buteo with 65,000 and 62,000 cells/mm2, respectively.

A negative correlation between ganglion cell density and cell body size was found in all the species studied. The specializations of the temporal retina showed a rather homogeneous population of medium sized neurons, while the nasal foveas showed a homogeneous population of smaller ganglion cells. Finally, the peripheral retina showed a heterogeneous population of large, medium, and small ganglion cells. Predatory behavior appears to be closely related to foveal specializations, and is best exemplified in the eagle and hawk and to a lesser extent in the chimango.
Relationship between the tendon of the long head of biceps brachii and the glenoidal labrum in humans
Authors: Pal G. P. , Bhatt R. H. , Patel V. S.
Published: February 2005

The relationship between the tendon of the long head of the biceps brachii muscle and the glenoidal labrum was investigated in a large number of dissected human shoulder joints. In about 70% of the specimens examined, the labrum was deficient at the posterosuperior margin of the glenoid because the tendon of the biceps coursed over this margin to blend with the labrum. Because of this, a small crescentic accessory facet was observed at the posterosuperior margin of the glenoid. In the majority of cases, the tendon of the biceps blended with the glenoidal labrum, and only a small part of the tendon attached to the supraglenoid tubercle. However, in 25% of the specimens, the major portion of the tendon was attached to the supraglenoid tubercle.
Effects of aging on the neuroglial cells and pericytes within area 17 of the rhesus monkey cerebral cortex
Authors: Peters Alan , Josephson Karen , Vincent Stephen L.
Published: February 2005

An electron microscopic analysis has been carried out to compare the neuroglial cells and pericytes within the primary visual cortex, area 17, of young (5–6 years) and old (25–35 years) rhesus monkeys. All of the neuroglial cell types accumulate inclusions within their cytoplasm as they age, and the inclusions within the astrocytes and oligodendrocytes are essentially characteristic of those cell types. The astrocytes probably acquire their inclusions by phagocytosis, and it is suggested that the inclusions in the oligodendrocytes are caused by an agerelated degeneration of the myelin sheaths they produce. The inclusions within the microglia are very heterogeneous. They are more massive than in the other neuroglial cells, so that their inclusions may almost fill the microglia. Pericytes also accumulate inclusions with age and there is evidence to suggest that they empty the contents of their inclusion vacuoles directly into the capillaries. On the basis of counts of the numbers of profiles of neuroglial cells displaying nuclei in thin sections, the only cells to increase in number with age are the microglia. They show an increase of about 44% when the cortices of young and old monkeys are compared.
Localization of smooth‐muscle markers in the ovaries of some ectothermic vertebrates
Authors: Van Nassauw Luc , Harrisson Fernand , Callebaut Marc
Published: February 2005

In the present study, we have localized desmin and α‐smooth‐muscle actin in the ovaries of the zebrafish, the axolotl, and the red‐eared turtle, using the unlabelled antibody peroxidase‐antiperoxidase technique. In the axolotl ovary both smooth‐muscle markers were demonstrated in cord‐like structures, extended along ovarian blood vessels, and in some inner ovarian epithelium cells. In the ovaries of the teleost, smooth‐muscle‐like cells are detected in a suspensory apparatus formed by venous cords, the tunica albuginea, and the coat around the ovarian artery. Also, in the turtle ovary, smooth‐muscle‐like cells were found in a suspensory apparatus formed by chordae, the tunica albuginea, and the theca externa of the ovarian follicles. At the present time, the prevailing hypothesis is that, in addition to a role in the mechanical support, the smooth‐muscle‐like cells in the ovaries of these vertebrates seem to be important with respect to ovarian contractile processes.
Equine myenteric plexus with special reference to the pelvic flexure pacemaker
Authors: Burns G. A. , Cummings J. F.
Published: February 2005

Sellers et al. (1979, Am. J. Phys., 237: E457–E464) proposed a pelvic flexure pacemaker mechanism to account for the bidirectional contraction waves needed to both retain ingesta within the right ventral colon for cellulose digestion and terminal fermentation and to transport the digesta distad once the process has been completed. To corroborate the presence of a pelvic flexure pacemaker, we prepared whole mount samples of the tunica muscularis from 23 horses at ten sites along the large colon, cecum and jejunum. Following smooth muscle enzymatic digestion, somata of the myenteric plexus were stained with an RNA‐specific agent, Cuprolinic blue. These somata were quantified at each site to establish any regional variations in neuronal density. Results indicated an increased neuronal density at the level of the pelvic flexure, especially in the region of the left dorsal colon. The increased neuronal density at the left dorsal colon compared to the other sampling sites was statistically significant (Wilcoxon signed rank test, P<.01 at each sampling site). There was remarkable size variation (from 10–60 μ) among neurons at the individual sampling sites. However, no statistically significant size discrepancy existed between sampling sites (Friedman's rank test, P=.10). The 23 horses ranged from 6 months to 15 years of age. No age‐related differences in neuronal density was discovered (Kruskal‐Wallis ANOVA test, P>.05). Neuronal densities did not vary on the basis of sex (Wilcoxon signed pairs test, P>.05). These neuronal counts serve both as corroborative evidence for the pelvic flexure pacemaker hypothesis and as standard values for neuronal density at each of our sampling sites. These standards will provide an important foundation for future studies in gastrointestinal motility and enteric pathology.
Tenascin localization in skin wounds of the adult newt Notophthalmus viridescens
Authors: Donaldson Donald J. , Mahan James T. , Yang Hui , Crossin Kathryn L.
Published: February 2005

Earlier studies have shown that the extracellular matrix (ECM) protein tenascin (TN) is present between uninjured epidermal cells of urodele appendages, but is absent from most of the mesenchymally derived ECM. Following appendage amputation, this distribution is reversed. TN is lost from the epidermis and appears in the ECM of the stump and the regeneration blastema. In the present study, monoclonal and polyclonal antibodies to TN were used to localize this protein immunohistochemically in limbs of the adult urodele Notophthalmus viridescens at various stages following skin removal with or without damage to underlying muscle to determine (1) if the loss of TN by the epidermis and its gain by mesenchymal tissues occurs in wounds that do not require regulation by epigenetic mechanisms, and (2) if TN is present in the provisional wound matrix beneath migrating epidermal cells. In addition, skin explants were cultured on TN‐coated dishes to learn if TN possesses active sites that can support epidermal cell migration. The results indicate that simple wounding leads to the same TN patterns as occurs following limb amputation. Tenascin loss from the epidermis could be seen as early as 6 hr after wounding, a time during which migrating epidermal cells are moving over the wound bed. During this period, there was no evidence of TN in the provisional wound matrix. In contrast to collagen, which supports considerable epidermal cell migration from skin explants, TN allowed no more migration than did the inactive protein, myoglobin.
Anionic site and immunogold quantitation of heparan sulfate proteoglycans in glomerular basement membranes of puromycin aminonucleoside nephrotic rats
Authors: Rada Jody A. , Carlson Edward C.
Published: February 2005

Renal glomerular basement membranes (GBMs) exhibit a charge‐selective barrier, consisting of heparan sulfate proteoglycan (HSPG) that restricts the passage of anionic molecules into the urine. Previous efforts to localize the HSPG core protein within various layers of the GBM have been contradictory. Furthermore, attempts to correlate proteinuria in several disease states with a decrease in anionic sites of HSPG core protein have yielded conflicting results.

When antibodies to HSPG from the EHS tumor matrix [anti‐(EHS) HSPG] and GBMs [anti‐(GBM) HSPG] were used together with immunogold to label renal tissues from puromycin aminonucleoside nephrotic (PAN) rats, immunolabeling results indicated that a portion of the protein core recognized by anti‐(EHS) HSPG was significantly reduced, while immunolabeling with anti‐(GBM) HSPG was only slightly reduced in early PAN. Anionic sites (stained with the cationic probe, polyethyleneimine) within the lamina rara externa of the GBM remained unaltered throughout the course of PAN.
Distribution of actin isoforms within cells of the seminiferous epithelium of the rat testis: Evidence for a muscle form of actin in spermatids
Authors: Oko Richard , Hermo Louis , Hecht Norman B.
Published: February 2005

Recently, a cDNA that coded for an enteric smooth muscle γ‐actin (SMGA) that was expressed in post‐meiotic mouse testicular cells was identified. To determine the cellular location(s) of the protein encoded by this cDNA, this SMGA was probed for by immunocytochemistry in the cells of the seminiferous epithelium with two different monoclonal antibodies (Mabs), B4 and HUC 1–1, known to be muscle actin selective. As a control, we also examined the immunoreactivity of a third Mab, C4, that reacts with all non‐muscle and muscle vertebrate isoactins. Using light and electron microscopy, a progressive increase in immunolabeling was observed with the muscle selective HUC 1–1 Mab over a loose actin filamentous network distributed throughout the cytoplasm of steps 4–16 spermatids. Thereafter, the labeling decreased such that at step 17 spermatids, only cytoplasmic labeling in the tail of the spermatids was observed. No labeling of this network was noted with the C4 or B4 Mabs. However, myoid cells enveloping seminiferous tubules and smooth muscle cells of interstitial blood vessels demonstrated comparable intense labeling with each of the three Mabs. The C4 Mab intensely labeled actin filaments of the Sertoli‐Sertoli and Sertoli‐spermatid ectoplasmic specializations. Also well labeled were numerous actin filaments found in the apical Sertoli cell processes encapsulating the heads of late step 19 spermatids at stage VII of the cycle of the seminiferous epithelium. In addition, actin filamentous bundles enveloping tubulobulbar complexes of the late spermatids within the Sertoli cell apical processes were intensely labeled. The actin filaments in the Sertoli apical processes and surrounding the tubulobulbar complexes were also strongly immunolabeled with the HUC 1–1 Mab. The C4 Mab but not the B4 or HUC 1–1 Mabs, recognized actin in the subacrosomal space of steps 4–18 spermatids. This study suggests that there are muscle isoforms of actin within the cytoplasm of developing spermatids and within apical processes of Sertoli cells.
Intercellular communication within the rat anterior pituitary gland. III. Postnatal development and periodic changes of cell‐to‐cell communications in female rats
Authors: Soji Tsuyoshi , Nishizono Hisanori , Yashiro Takashi , Herbert Damon C.
Published: February 2005

Cell‐to‐cell communication by gap junctions was investigated in the female rat anterior pituitary gland from 10 through 45 days of postnatal development and in 60‐day‐old animals. Gap junctions initially appeared between adjacent folliculo‐stellate cells on day 25. Their appearance in female rats was 5 days later than that observed in males (Soji et al., 1990). Gap junction number increased until the animals became 40 days of age, when they reached a level that resembled that found in adults. In addition, a correlation was evident between the frequency of gap junctions and stages of the estrous cycle, where they were most numerous during either proestrus or estrus. These results along with those previously published suggest that gap junction formation within the female rat hypophysis is in part modulated by both gonadal steroid hormones as well as prolactin.
Estimated intracortical bone turnover in the femur of growing macaques: Implications for their use as models in skeletal pathology
Authors: Burr David B.
Published: February 2005

Although macaques have been used widely to study the dynamics of bone remodeling, there have been few comparisons to skeletal tissue turnover in humans. This study analyzes variation in bone microstructure with respect to gender, age, and body weight in growing macaques to determine whether the pattern of osteonal remodeling in macaques is like that in analogous bones of humans. Histomorphometric measurements were made on femoral midshaft cross‐sections of 54 macaques from the Cayo Santiago skeletal collection. These data show that variation in bone microstructure occurs independent of gender, age, and body weight in macaques. Moreover, intracortical bone turnover in the macaque femur is much slower than in humans, making them poor models to study the effects of weightlessness, but good models to study low turnover skeletal dysplasias.
Human odontoblasts contain S‐100 protein‐like immunoreactivity
Authors: Lombardi Tommaso , di Felice Roberto , Samson Jacky
Published: February 2005

S‐100 protein is a group of three closely related isoforms (S‐100ao, S‐100a, and S‐100b). This protein was first described as unique to the nervous system but it has also been identified subsequently in a variety of cell types of neuroectodermal (i. e., melanocytes, glial cells) and non‐neuroectodermal origin (i. e., Langerhans cells, adipocytes, chondrocytes). In the present investigation the presence of S‐100 protein was studied in human odontoblasts using a specific polyclonal antibody directed against S‐100 protein in immunoperoxidase labelling experiments. The S‐100 protein was detected in the cytoplasm of odontoblasts. This result suggests that S‐100 protein can play a role in odontoblast functions.
Changes in the distribution of filipin‐sterol complexes in the boar sperm head plasma membrane during epididymal maturation and in the uterus
Authors: Seki Naohiko , Toyama Yoshiro , Nagano Toshio
Published: February 2005

The distribution of filipin‐sterol complexes (FSCs) and intramembranous particles (IMPs) in the plasma membrane of the late spermatid of the boar and of the sperm obtained from the epididymides, ejaculates, and uterus 2 hours after mating was examined by a freeze‐fracture replica technique. In the late spermatid, the FSC density was found to be very low. A majority of the FSCs in the acrosomal plasma membrane (APM) appeared as protuberances on the E face in the epididymal, ejaculate, and uterine sperm. The density of the FSCs in the principal segment (PS) of the APM was 291 ± 44 FSC/μm2 (mean ± standard deviation, S. D. ), 322 ± 41 FSC/μm2 and 355 ± 31 FSC/μm2 in the caput, corpus, and cauda epididymidis, respectively. In comparison with the cauda epididymal sperm, the FSC density gradually decreased in the PS of the ejaculated (277 ± 39 FSC/μm2) and uterine sperm (243 ± 50 FSC/μm2). The reduction was especially remarkable in the equatorial segment (ES), where the density of FSCs in ejaculated and uterine sperm decreased to about half and less than half of that in the cauda epididymal sperm, respectively.

Large (13 nm) and small (8 nm) IMPs were distributed evenly and densely in the P face of the APM in the late spermatid, epididymal, and ejaculated sperm. In the uterine sperm, IMP‐free areas were observed in the P face of the plasma membrane, a feature thought to represent one of the capacitation changes of the boar sperm.
Axon terminals on betz cell somata of area 4 in rhesus monkey throughout adulthood
Authors: Tigges Johannes , Herndon James G. , Peters Alan
Published: February 2005

Previous work in our laboratory demonstrated an age‐related decline in the size of Betz cell somata in cortical area 4 of the adult rhesus monkey brain. The present study was conducted to determine whether changes might also occur in the axon terminals upon these cortical cells. Tissue from area 4 was collected from seven rhesus monkeys and prepared for electron microscopy. The ages of the monkeys ranged from 5 to 35 years, covering the entire adult life span of this species. A total of 140 Betz cell profiles (20 per monkey) were examined. Measurements of these profiles confirmed our earlier finding of a decline in the perimeters of Betz cell somata with advancing age. The 1,540 axon terminals upon these cells, however, remained unchanged in size and length of membrane apposition, as well as in their number of mitochondria throughout the adult life (≥5 years) of the rhesus monkey. In addition, the total number of axon terminals on Betz cells did not change with age.

Because the axosomatic terminals showed no age‐associated changes, the material was used to calculate parametric characteristics of Betz cells and associated terminals. Betz cell somata of the rhesus monkey were estimated to have a mean membrane surface area of 5,700 μm2. Axosomatic terminals on Betz cell somata had a mean appositional area of about 3.33 μm2 and covered about 15% of the somal surface. Thus, on average, each Betz cell appeared to receive approximately 260 axosomatic terminals.

There were also some conspicuous age‐associated changes in the motor cortex that were not quantified. These included an accumulation of lipofuscin and the presence of a novel inclusion body in the somata of Betz cells. Age‐related occurrences in the neuropil included the degeneration of axons and their myelin, membrane‐bound holes, and neuritic (senile) plaques.
Observation of the anterior supracostal muscles
Authors: Nelson Marita L. , Burkle Christopher , Ricardo Richard , Shibao Stacie
Published: February 2005

A pair of anomalous supernumerary muscles has been found in a single cadaver which fit the classic description of the Musculus supracostalis anterior. The muscles took origin from the first rib deep to the two pectoral muscles and between the origins of the pectoralis minor and serratus anterior muscles. They were directed inferiorly to insert on the upper margin of the fourth rib. The nerve supply of one muscle of the pair was determined to be from the collateral branch of the second right intercostal nerve. This supports the theory that these rare muscles may be derived from a single external intercostal muscle which grew to span several intercostal spaces.
Segregation of secretory material in all elements of the Golgi apparatus in principal epithellal cells of the rat seminal vesicle
Authors: Clermont Y. , Rambourg A. , Hermo L.
Published: February 2005

At the apex of the epithelial principal cells of the seminal vesicle, there appears to be two types of mature secretory granules, i. e., large and small. Both types of secretory granules showed an eccentric electron‐dense spherical body with one pole attached to the delimiting membrane. The remainder of the large granule surrounding the eccentric body showed a granulofilamentous texture, whereas that of the small granule was electron lucent. The formation of these two types of granules was traced back to the various elements of the Golgi stacks. In the case of the large granules, the earliest stage of segregation of the precursor of the eccentric dense body was observed in distensions of the cis‐element. Within distensions of all subjacent saccules, the dense bodies continued to be present but progressively increased in size while remaining attached to the saccular membrane. Following separation from the trans‐face of the stack, the large prosecretory granules continued to increase in size by fusing with each other. The very large prosecretory granules, as they migrated toward the cell apex to become mature secretory granules, reduced in size prior to exocytosis. The small granules formed exclusively on the trans‐aspect of the Golgi stacks and did not appear to fuse with each other. Observations on the formation of the large prosecretory granules within the Golgi apparatus and of the eccentric body in particular, which may be taken as a marker of the saccular membrane, were suggestive of a cis‐trans migration and renewal of Golgi saccules.
The external genitalia of female gibbons, Hylobates (H.) lar
Authors: Dahl Jeremy F. , Nadler Ronald D.
Published: February 2005

The external genitalia of one perimenarcheal and five adult female white handed‐gibbons (Hylobates (H.) lar) were examined to clarify their gross anatomy. It was found that the vulval structures were complex and exhibited inter‐individual variation in arrangement. This complexity appears to result from an ontogenetic process by which the tissues of the vaginal rim (the labia minora) bud‐off and extrude extensions toward the vagina immediately prior and subsequent to menarche. Two of these lobular structures surround the urethral meatus with associated prepuce and frenulum and vestigial labia majora, undergo cycles of tumescence and detumescence during intermenstrual intervals. The complex form of the external genitalia and the presence of a swelling cycle are unusual for a monogamous species, are contrary to current applications of sexual selection theory, and raise questions about the significance of mate choice in hominoid evolution.
The differentiation of the skin and its appendages. II. Altered development of papillary ridges following neuralectomy
Authors: Morohunfola Kehinde A. , Jones Terrel E. , Munger Bryce L.
Published: February 2005

In order to test the hypothesis that the nervous system is an important determinant of skin differentiation, deletions of the left lumbosacral dorsal root ganglia (DRGs), the sources of cutaneous afferents to the left hindpaw, were performed on opossum pups at day 1 when hindpaws have just begun to be innervated. At birth, each lumbosacral DRG measures about 200 μm rostrocaudally and a deletion measuring 1 mm would span 4–5 DRGs.

Following survival periods of 5–24 days, serial sections through the trunk documented partial left lumbosacral DRG deletion and a variable degree of spinal cord destruction. The blood supply to the trunk and hindpaws was preserved. Bilateral enlargement of residual DRGs was observed and regenerating skin at the site of the deletion was hyperplastic and hyperinnervated.

The skin of the plantar pads of the hindpaws was studied following the neuralectomies. Statistically significant differences were observed between the left (experimental) and right (control) hindpaws. The density of innervation of the left hindpaw was reduced compared to the right hindpaw, development of papillary ridges was retarded by 3–4 days, and non‐innervated Merkel cells were hypogranulated. This period of delay in ridge development is probably a reflection of the expansion of residual DRGs into the peripheral domains of deleted DRGs. The present study confirms a role for afferent nerves in the timing of cutaneous differentiation and a mutual trophic dependence between cutaneous nerves and Merkel cells in the epidermis.
Renewal of enterochromaffin cells in the rat caecum
Authors: De BruïNe A. P. , Dinjens W. N. M. , Zijlema J. H. L. , Lenders M.‐H. , Bosman F. T.
Published: February 2005

The localization, morphology, and neurohormonal peptide content of neuroendocrine cells have been extensively investigated. Relatively little is known about the kinetics of growth and differentiation of these cells. We studied the kinetics of enterochromaffin (EC) cells in the caecum of the rat, by applying the thymidine analogue 5‐bromo‐2′‐deoxyuridine (BrdU), to identify cells in S‐phase, administered in pulse‐chase and synchronous continuous labeling experiments. By double indirect immunofluorescence staining of tissue sections, using antibodies against serotonin and BrdU, percentages of BrdU positive EC cells could be enumerated, from which cell‐kinetic parameters were derived. The following conclusions were drawn: (1) EC cells are renewed by proliferation of EC cells and by recruitment from proliferating precursor cells. (2) Caecal EC cells appear to consist of a relatively rapidly renewing and migrating fraction (60–65%) with a turnover time of approximately 16 days and a relatively slowly renewing and possibly stationary fraction (35–40%) with an estimated turnover time of approximately 150 days. (3) Seventy percent of the EC cells are localized in the lower half of mucosal crypts, 30% in the upper half. After prolonged labeling the percentage of labeled EC cells in the lower crypt half always exceeds that in the upper crypt half. This decrease in labeled EC cells during migration towards the mucosal surface indicates loss of endocrine cells, possibly owing to loss of endocrine characteristics. © 1992 Wiley‐Liss, Inc.
Intercellular communication within the rat anterior pituitary gland: IV. Changes in cell‐to‐cell communications during pregnancy
Authors: Soji Tsuyoshi , Yashiro Takashi , Herbert Damon C.
Published: February 2005

Cell‐to‐cell communication by gap junctions was investigated in the female rat anterior pituitary gland from 9 through 21 days of pregnancy and subsequently on days 2 and 20 of the lactational period. Compared with intact estrus females, the major morphological characteristics of the pituitary gland during pregnacy were remarkably developed prolactin cells and gonadotrophs. A close relationship of both cell types was clearly evident. Gap junctions were present at each of the time intervals studied; however, they were noted only between adjacent folliculo‐stellate cells. No remarkable changes were noted in the number of gap junctions during the middle stage of pregnancy (day 9 through day 15), with the relative number resembling that found in intact, 90‐day‐old controls during estrus (0.47 ± .01 junctions/follicle‐control vs. 0.50 ± 0.08—day 15 of pregnancy). In the later stages of pregnancy (day 17 through day 21), a demonstrable increase was observed (0.64 ± 0.10—day 17, 0.79±0.11—day 19 and 0.72±0.12—day 21), whereas during the lactation, this pattern returned to that seen at midpregnancy. Since both prolactin and the gonadal steroid hormones dramatically fluctuate during pregnancy and lactation, it is postulated that they may have an active role in gap junction formation during these two phase of reproductive life. © 1992 Wiley‐Liss, Inc.
Novel inclusion bodies in Betz cells of cortical area 4 of aged rhesus monkeys
Authors: Tigges Johannes
Published: February 2005

Seven adult rhesus monkeys ranging in age from 5 to 35 years were studied in an ultrastructural investigation of cortical area 4. Some Betz cells of layer 5 contained a perikaryal inclusion body (IB) of a unique and characteristic ultrastructural configuration that has not previously been described. The IBs consist of a regular array of three sets of equidistant parallel sheets and are not membrane bound. The distance between the sheets measures ∼ 80 nm. The three sets of sheets intersect at an invariable angle of 60°, forming a regular geometric structure. Each sheet comprises a single layer of parallel and densely packed straight filaments, which are ∼10 nm thick. Thus the IBs present highly ordered crystalline arrays of filaments. The occurrence and number of IBs may be age related, since they appeared only in monkeys in mid to late adulthood and were most numerous in the oldest monkey. © 1992 Wiley‐Liss, Inc.
Morphological and mapping studies of the paranodal and postnodal levels of the neural plate during chick neurulation
Authors: Schoenwolf Gary C.
Published: February 2005

The morphology of the paranodal and postnodal levels of the neural plate as well as the fate of its cells was examined in chick embryos at stages 3–11. The morphology of the paranodal and postnodal levels of the neural plate closely resembles that of the prenodal neural plate. Furthermore, during shaping and bending of the neural plate, these levels undergo changes similar to those of the prenodal level. In short, the paranodal and postnodal levels of the neural plate consist of a pseudostratified columnar epithelium that thickens dorsoventrally and narrows mediolaterally and then undergoes localized furrowing and folding. Fate mapping revealed that at mid‐neurula stages, the prospective hindbrain and spinal cord levels of the neuraxis flank the primitive streak. Hensen's node moves caudally with respect to these future neuraxial levels as it regresses during the latter stages of gastrulation. Cells of the medullary cord, the rudiment of the secondary portion of the neural tube, arise in the vicinity of the cranial portion of the primitive streak, near the caudal end of the postnodal levels of the neural plate. Thus, during stages of gastrulation and primary neurulation, the precursor cells of the primary and secondary portions of the neural tube (spinal cord) lie in close proximity to one another. This study provides new information on the morphology and extent of the paranodal and postnodal levels of the neural plate, the changes these areas undergo during shaping and bending oif the neural plate, and the contributions of its cells to the primary and secondary levels of the neural tube, increasing our understanding of the complex events underlying avian gastrulation and neurulation. © 1992 Wiley‐Liss, Inc.
Studies on wound healing in the neuroepithelium of the chick embryo
Authors: Lawson Aaron , England Marjorie A.
Published: February 2005

Wound healing has been studied by light microscopy, SEM, and TEM in the neuroepithelium of the early neurula (stages 6 and 8) and advanced neurula (stages 10 and 12) chick embryos. Healing involves two major events: (1) apposition of the wound edges and (2) restitution of the neuroepithelium at the wound site (i. e., restoration of the epithelial integrity of neuroepithelium). Apposition of the wound edges occurs within the first 15 minutes of re‐incubation and involves the entire lenght of the wound. The main event during restoration is a change in the shapes of the rounded cells to elongated forms (i. e., spindle, wedge, and inverted wedge shapes). Wounds of younger embryos heal faster than those of older ones. © 1992 Wiley‐Liss, Inc.
Examination by scanning electron microscopy of oviductal epithelium of the prolific Chinese Meishan pig at follicular and luteal phases
Authors: Abe Hiroyuki , Oikawa Taneaki
Published: February 2005

The luminal surfaces of epithelial cells in the fimbriae, ampulla, isthmus, and utero‐tubal junction of the oviducts of the prolific Chinese Meishan pig at follicular and luteal phases of the estrous cycle were examined by scanning electron microscopy. Marked cyclic changes were observed on the surfaces of cells in the fimbriae and ampulla, but little change was found in the isthmus and at the utero‐tubal junction. The cells of the fimbrial epithelium in the follicular phase were densely ciliated, and the cilia partially concealed the bulbous processes of the secretory cells. In the luteal phase, the secretory cells predominated in the epithelium, and most of the ciliated cells were hidden by the processes of the secretory cells. The ampullar epithelium showed similar changes, but to a lesser extent. In the isthmus and at the utero‐tubal junction, the secretory cells had many microvilli on their bulbous processes at the follicular phase, but they were flat and the microvilli were fewer in number and shorter in length during the luteal phase. Conspicuous solitary cilia protruded from the surfaces of secretory cells in the fimbriae and ampulla during the luteal phase. These results demonstrate that there are regional variations in the cyclic changes associated with the oviductal epithelial cells of the Chinese Meishan pig. © 1992 Wiley‐Liss, Inc.