bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of epidermal growth factor receptor (EGFr) immunoreactivity in human cutaneous nerves and sensory corpuscles
Authors: Vega J. A. , Vazquez E. , Naves F. J. , Calzada B. , Del Valle M. E. , Represa J. J. 
Published: February 2005

AbstractBackground: The epidermal growth factor receptor (EGFr) binds both epidermal growth factor (EGF) and transforming growth factor α (TGFα), which are currently considered among putative growth factors playing a role in the nervous system. EGFr and their ligands have been localized in the mammalian peripheral nervous system. The present study was undertaken to investigate whether nerves and sensory corpuscles supplying human glabrous skin express EGFr.Methods: Formaldehyde fixed, paraffin embedded samples of finger‐tip digital skin obtained from adult healthy subjects were processed for indirect PAP immunohistochemistry using a monoclonal antibody against an epitope of the intracellular domain of EGFr. To ascertain the localization of EGFr immunoreactivity, neurofilament proteins (NFP), S100 protein (S100P), and epithelial membrane antigen (EMA) were studied in parallel to label axons, Schwann cells, and perineurial cells, respectively, as well as their corpuscular derivatives.Results: A variable intensity of EGFr immunostaining was regularly observed in the perineurium and Schwann cells, and occasionally in the axons of nerve bundles. EGFr immunoreactivity was also present in the axon and lamellar cells of Meissner corpuscles, and within the axon, inner‐core, outer‐core, and capsule of Pacinian corpuscles.Conclusions: Present results demonstrate that human cutaneous nerves and sensory corpuscles express EGFr suggesting a role for peptides able to bind EGFr, i.e., EGF and TGFα, in the human peripheral nervous sensory system. © 1994 Wiley‐Liss, Inc.
Ultrastructure and histochemistry of human anterior lingual salivary glands (glands of blandin and nuhn)
Authors: Tandler Bernard , Pinkstaff Carlin A. , Riva Alessandro 
Published: February 2005

AbstractBackground: Speciamens of human anterior lingual salivary glans obtained by surgery and by dissection of cadavers were studied ultrastructurally and histochemically.Methods: Specimens were obtained by surgery for ultrastructural study. Other specimens for histochemistry were obtained by dissection of fresh cadavers. Tissues for electron microscopy were fixed and processed by conventional mesns. Formalin‐fixed cadaver specimens were subjected to a battery of tests for glycoconjugates.Results: The anterior lingual salivary glands are composed predominantly of mucous tubules (which come in two distinct sizes: large and small), seromucous demilunes, and rare seromucous acini. Regardless of tubule size, mucous cells are typically in appearance and, like mucous cells in other human salivary glands, contain filamentous bodies. Histochemically, the larger tubules contain neutral glycoproteins, low concentrations of sialoglycoproteins, and large amounts of sulfated glycoproteins. The small mucous tubules contain neutral glycoproteins, much sialoglycoprotein, and relatively small amounts of sulfated glycoprotein. The seromucous cells, whether demilunar or acinar, are identical. They contain numerous secretory granules, which show a spectrum of internal patterns from one individual to another. These cells have considerable concentrations of neutral‐ and sialoglycoproteins and lower concentrations of sulfated gly‐coproteins. Countrary to previously published reports, we could find no differences in the ratio of mucous to seromucous cells along the anteriorposterior lingual axis: there was no gradient of seromucous cells in our specimens. The ducts in the anterior lingual salivary glands are not precise counterparts of those in the major salivary glands, since the former have no capsules, hence lack lobulation. Without these familiar structural landmarks, the only duct that can be identified with certainty is the intercalated duct, and then only if it is in continuity with or lies close to a secretory endpiece. Such ducts consist of simple cuboidal epithelium of prosaic appearance. The ductular epithelium gradually thickens and gives rise to what appear to be excretory ducts consisting of columnar cells with few mitochondria. Scattered within the walls of the walls of the larger ducts are patches of typical striated ducts wherein the taller cells display basal striations resulting from highly folded basal plasma membranes and numerous, vertically oriented, virgulate mitochondria. In other atypical regions of the excretory duct, basal cells may have a primary cilium that juts into the intercellular space.Conclusions: There is a high degree of structural variability in human anterior lingual salivary glands. Because of the technical difficulties in collecting pristine saliva from these glands, the precise functions(s) of these organs remains unknown. © 1994 Wiley‐Liss, Inc.
Changes in proteoglycans of ageing and osteoarthritic human articular cartilage: An electron microscopic study with polyethyleneimine
Authors: Sauren Yvonne M. H. F. , Mieremet René H. P. , Lafeber Floris P. J. G. , Huber‐Bruning Olga , Groot Cornelis G. , Scherft Johannes P. 
Published: February 2005

AbstractBackground: Ageing and osteoarthritic (OA) cartilage show characteristic alterations in chondrocyte morphology and in the composition and content of matrix proteoglycans (PGs). Data concerning matrix components are mostly of biochemical nature. Ultrastructural histochemistry is needed to gain more information about distribution of these altered matrix components.Methods: We used the cationic dye polyethyleneimine (PEI) to visualize at the EM level alterations in the distribution and dimensions of PGs of human healthy young, healthy aged, and OA articular cartilage.Results: Young cartilage contained PEI‐positive granules in the superficial layer and big winding PEI‐positive structures in the deeper layers. In the healthy aged tissue, PEI‐positive granules were observed throughout the matrix and smaller winding structures were present in the deeper layer. In OA cartilage both types of PEI‐positive structures were absent in the superficial layer. Deeper in the matrix PEI‐positive granules could be demonstrated. Moreover, PEI‐positive angular structures were observed in the deeper zones.Conclusions: The differences in PEI‐positive structures are a good reflection of the differences in PGs between young, ageing, and OA cartilage as demonstrated in biochemical studies. PEI, used at the EM level, gave more precise information concerning the localized changes in quality, quantity, and location of PGs in articular cartilage during ageing and disease. © 1994 Wiley‐Liss, Inc.
Abandonment of germ cells in the embryonic chick ovary: TEM and SEM studies
Authors: Ukeshima Atsumi 
Published: February 2005

AbstractBackground: Embryonic chick ovary forms medulla and cortex successively in early developmental stages. Unlike the cortex, which is a functioning tissue in the adult, the medulla regresses as development advances. Although germ cells are included in these respective regions, their behavior within these regions is different. This study focuses on the fate of germ cells in the medulla of both ovaries.Methods: Germ cells found in the medulla of the developing chick ovary from 7 to 19 days of incubation were observed by TEM and SEM.Results: From 10 days of incubation onward, medullary germ cells in both right and left ovaries were often released into medullary lacunae. During the releasing process, germ cells were covered by thin cytoplasm of epithelial cells of the lacunae. After release, however, they were freed from the thin coat of epithelial cells. Abandoned germ cells were seen in the lacunae as solitary cells or as a mass composed of several cells. In the right ovary, germ cells released into the lacunae were subsequently found at the holes of the ovarian surface, which were continuous with the medullary lacunae. Moreover, germ cell death was often found in late stages in the medullary tissues of both right and left ovaries.Conclusions: The present study clarifies the fact that chick germ cells of the medulla of both right and left ovaries are either discarded by a process of programmed cell death and/or released into medullary lacunae with increasing embryo age. © 1994 Wiley‐Liss, Inc.
Muscles of the pelvic outlet in the rhesus monkey (Macaca mulatta) with special reference to nerve supply
Authors: Akita Keiichi , Sakamoto Hirokazu , Sato Tatso 
Published: February 2005

AbstractBackground: The Manner of innervation of the muscles of the inferior limb, pelvic outlet, and tail in rhesus monkey (Macaca maulatta) was investigated in detail in 11 pelvic halves of lour males and two females.Results: The origins of the pudendal nerve were widespread and overlapped the sacral plexus. After removal of the bone structures, detailed dissection revealed the origin of the pudendal nerve to ventrocaudally overlap the sacral plexus. This dorsoventral branching pattern between the sacral plexus and the pudendal nerve is similar to that in Urodela (akita, 1992b) Lacertilia (Akita, 1992a) and AVes (Akita et al., 1992a), and is a basis for morphological understanding of the muscles of the pelvic outlet.Conclusion: The muscles of the pelvic outlet consist of the leavtor, sphincter, and tail muscle groups, based on the stratification of the supplying nerves the former two groups likely dervice from the ventral muscles of the inferior limb, and the latter group from the ventral caudal (trunk) muscles. © 1995 Wiley‐Liss, Inc.
Morphometric evaluation of volume shifts between intra‐ and extra‐cellular space before and during global ischemia
Authors: Schmiedl Andreas , Haasis G. , Schnabel Ph. A. , Gebhard M. M. , Richter J. 
Published: February 2005

AbstractBackground: It is well known that all forms of cardiac arrest lead to global ischemia combined with alterations in cellular and interstitial volume. The aim of this study was to investigate the nature of these alterations with respect to different methods of cardiac arrest and establish the extent of their mutual influence at the onset as well as during the course of global ischemia.Methods: Three tested clinical methods were employed to induce cardiac arrest by a) aortic cross clamping, b) coronary perfusion with the cardioplegic solution St. Thomas, and c) coronary perfusion with the cardioplegic solution histidine‐tryptophane‐ketoglutarate (HTK). The arrested hearts were subjected to global ischemia at 25°C. The size of the myocytes, as well as the interstitial space of myocytes, was determined morphometrically. The contraction state of myocytes was evaluated according to a score.Results: We found that the degree of contraction, as well as nature of alterations in the cellular and interstitial volumes, depended both on the form of cardiac arrest and on the duration of ischemia. The following relationships were established. High contraction at the onset of ischemia leads to expulsion of fluid from the interstitium between bundles of myocytes into the tissue clefts increasing their size. The decrease in contraction during ischemia leads to narrower tissue clefts. Cellular swelling at the onset of and during ischemia is caused by volume shifts between intracellular and interstitial space. An increase in cellular volume during global ischemia and/or additional contraction reduce the interstitium within bundles of myocytes. Sufficient relaxation and/or interstitial edema enlarge the interstitium.Conclusions: Cellular and intersticial alterations seen at the onset and during the course of ischemia are dependent upon the method of cardiac arrest. Furthermore, a considerable mutual influence is exerted by the alterations in cellular and interstitial spaces. © 1995 Wiley‐Liss, Inc.
Matrix metallproteinases and TIMP‐1 localization at sites of osteogenesis in the craniofacial region of the rabbit embryo
Authors: Breckon Jeremy J. W. , Hembry Rosalind M. , Reynolds John J. , Meikle Murray C. 
Published: February 2005

AbstractBackground: The matrix metalloproteinases (MMPs) are a family of closely related enzymes, the principal members being the collagenases, gelatinases, and stromelysins. They are synthesized and secreted by connective tissue cells and are capable of degrading all the components of connective tissue matrices at physiological pH.Methods: Patterns of synthesis and distribution of MMPs and their inhibitor, tissue inhibitor of metalloproteinases‐1 (TIMP‐1), are documented in the craniofacial region at sites of bone formation during both intramembranous (e.g., calvaria, maxilla, and mandible) and endochondral ossification (e.g., cartilaginous cranial base and synchondroses) using indirect immunolocalization.Results: MMPs and TIMP‐1 were detected both as bright intracellular accumulations, indicating active synthesis, and as diffuse matrix‐bound extracellular deposits. Gelatinase‐A had an extensive distribution in osteogenic tissues and was detected both in cells of the periosteum and spongiosum and as extracellular deposits in the osteoid layer of newly formed bone. In addition, gelatinase‐AB synthesis was detected in osteoclasts. All regions of the early cartilaginous cranial base produced MMPs and TIMP‐1 were also documented in early tooth germs and in Meckel's cartilage.Conclusions: These data document a prominent role for MMPs, and in particular gelatinase‐A, in mediating matrix degradation during osteogenesis. Their detection in tooth germs and Meckel's cartilage further indicates a role for MMPs and TIMP‐1 in matrix turnover during morphogenesis. © 1995 Wiley‐Liss, Inc.
Probing glucocorticoid‐dependent osteogenesis in rat and chick cells in vitro by specific blockade of osteoblastic differentiation with progesterone and RU38486
Authors: Tenenbaum Howard C. , Kamalia Nilupa , Sukhu Balram , Limeback Hardy , McCulloch Christopher A. G. 
Published: February 2005

AbstractGlucocorticoids and sex‐steroids can modulate osteogenesis in vivo and in vitro. Although the effects of glucocorticoids on bone cells in vitro have been described in detail, the role of sex‐steroids is not as well defined. We examined whether sex‐steroids influence bone metabolism indirectly by regulating glucocorticoid effects on bone. Interactions of the sex‐steroid progesterone or its analog RU38486 with the glucocorticoid dexamethasone (dex) were studied in functional assays of osteogenesis. Three osteoblastic models were evaluated:(1) the rat bone marrow stromal cell (RBMC) nodule system; (2) the chick periosteal osteogenesis (CPO) model; and (3) ROS 17/2.8 cells. RU38486, progesterone, and unlabelled dex competitively inhibited 3H‐dex uptake by ROS 17/2.8 cells as well as its (3H‐dex) binding to cytosol preps.Both RU38486 and progesterone inhibited dex‐induced increases in alkaline phosphatase in CPO cultures, in RBMC cultures, and in ROS 17/2.8 cells. Dex‐induced decreases in cell proliferation in ROS 17/2.8 cells were reversed by RU38486 but dex‐induced increases in proliferation in the CPO model were not affected. In CPO cultures, dex‐induced increases in collagen synthesis were inhibited completely by RU38486 and progesterone, Dex‐dependent nodule formation in the RBMC was blocked by RU38486. Both RU38486 and dex mediated reduction of calcium uptake in the CPO model but did not affect mineralized tissue area.The data indicate that RU38486 and progesterone competitively inhibit dex‐mediated stimulation of osteogenesis in vitro; this inhibition is exerted on early but not late stage differentiation events of osteoprogenitor cells. © 1995 Wiley‐Liss, Inc.
Functional movements of putative jaw muscle insertions
Authors: Goto Tazuko K. , Langenbach Geerling E. J. , Korioth Tom. W. P. , Hagiwara Masaaki , Tonndorf Monica L. , Hannam Alan G. 
Published: February 2005

AbstractBackground: The craniomandibular muscles control jaw position and forces at the teeth and temporomandibular joints, but little is known regarding their biomechanical behaviour during dynamic function. The objective of this study was to determine how jaw muscle insertions alter position during different jaw movements in living subjects.Methods: Computer 3D reconstruction of MR images and jaw‐tracking were combined to permit the examination of movement with six degrees of freedom. Maximum mandibular opening, protrusive and laterotrusive positions were recorded in four subjects, and the translation and rotation of the putative insertions of masseter, temporal, medial, and lateral pterygoid muscles were measured.Results: The sizes and shapes of regional attachments varied markedly among subjects, and their displacement patterns were different in specific muscles. For instance, when the jaw closed to the dental intercuspal position from maximum gape, the region near the superior insertion site of the masseter moved backward and upward, whereas the region near the inferior insertion site displaced mainly forward. In three subjects, the jaw's rotational center during this act was ∼26–34 mm below the mandibular condyles.Conclusions: Since the movements of each muscle part differ according to variations in the size and shape of insertion areas, individual musculoskeletal form, and patterns of jaw motion during function, the prediction of motion‐related muscle mechanics in any one subject is unlikely to be possible without direct measurement of the motion of visualized muscle parts. The present study shows that this information can be obtained. © 1995 Wiley‐Liss. Inc.
Microcirculation of gills and accessory respiratory organs of the walking catfish Clarias batrachus
Authors: Olson K. R. , Ghosh T. K. , Roy P. K. , Munshi J. S. D. 
Published: February 2005

AbstractBackground: An ability to extract oxygen directly from the atmosphere enables air‐breathing fish to survive otherwise debilitating hypoxic environments. Addition of accessory respiratory organs (ARO) necessitates changes in both the general circulatory system and the microcirculation of the respiratory epithelia. Understanding these modifications provides information on the efficiency of gas exchange organs as well as an indication of the evolutionary processes associated with adaptation to terrestrial habitats.Methods: Vascular organization and structure of gills and ARO of the facultative air‐breathing walking catfish Clarias batrachus were examined by scanning electron microscopy of vascular replicas and fixed tissue.Results: Well‐developed filaments are present on all four pairs of gill arches and they possess three vascular pathways: respiratory (arterioarterial), nutrient (arteriovenous), and interlamellar (arteriovenous), typical of teleosts. ARO, consisting of gill fans, dendritic organs on the second and fourth gill arch, and the suprabranchial epithelium are derived from gill tissue and retain structural features and arterioarterial vessels similar to gill filaments. Gill and ARO vessels are in parallel with each other, and together they are in series with the systemic circulation. Nutrient and interlamellar vessels are reduced in ARO.Conclusions: Other than the presence of multiple ventral aortas, and an additional vessel connecting the suprabranchial epithelium to the dorsal aorta, there are no vascular shunts or anatomical modifications that indicate spatial separation of flow through the heart or between gills and ARO. However, a mechanism is proposed that would prevent unsaturation of dorsal aortic blood by local myogenic vasoconstriction of gill vessels when the fish is in hypoxic water. Despite considerable differences in the gross features of ARO in Clarias and Heteropneustes fossilis: (Olson et al. 1990 J. Morphol., 203:165), there are striking similarities in vascular organization and respiratory islet structure that suggest these ARO evolved in a common silurid ancestor and were later modified into an everted arborescent organ or inverted air sac, respectively. © 1995 Wiley‐Liss, Inc.
Myosin heavy chain expression within the tapered ends of skeletal muscle fibers
Authors: Rosser Benjamin W. C. , Waldbillig Donna M. , Lovo Stacey D. , Armstrong Jacalyn D. , Bandman Everett 
Published: February 2005

AbstractBackground: The pectoralis muscle of the chicken contains fast‐twitch glycolytic fibers, which during development undergo a transformation in their myosin heavy chain (MyHC) content from embryonic to a neonatal to an adult isoform (Bandman et al., 1990). Little, however, is known of MyHC expression within the ends of these or other muscle fibers. Here we test the hypothesis that the tapered ends of mature skeletal muscle fibers contain a less mature MyHC isoform than that typically found throughout their lengths.Methods: We apply an ammoniacal silver histological stain for endomysium and monoclonal antibodies against neonatal and adult MyHCs of chicken pectoralis to transverse serial sections of pectoralis from five mature chickens. The “lesser fiber diameters” of populations of fibers from each bird are also measured.Results: Most (∼81.8%) of the small (<12μm) and none of the larger (>20μm) diameter fibers contain the neonatal MyHC. Following these smaller fibers through serial sections, we show that they are the tapered ends of the larger fibers. Whereas neonatal MyHC is restricted to the tapered fiber ends, adult MyHC is present throughout the entire lengths of all fibers. We also demonstrate acetylcholinesterase (AChE) activity at some of these fiber ends.Conclusions: We postulate that longitudinal growth of myofibrils in adult muscle is characterized by the sequential expression of MyHC isoforms similar to that observed in rapidly growing muscle and that the presence of the neurotransmitter hydrolase AChE at the tapered fiber ends may be related to the retention of neonatal MyHC. © 1995 Wiley‐Liss, Inc.
Kidney of elephants
Authors: Maluf N. S. R. 
Published: February 2005

AbstractBackground: Elephants are an important and isolated order. Their kidneys need substantial investigation and hitherto have not been portrayed even by a pyelogram.Methods: Pyelograms and injection of vessels with colored acrylic emulsions were done initially. Dissection was under fiberoptics using a dissecting microscope with frequent measurements. Special areas were cut for microscopy (light and electron) and photography. Glomerular counts were done by macerating weighed pieces of cortex and later finding the cortical fraction of the renal parenchyma.Results: The elephant kidney is devoid of dorsoventral symmetry. It is composed of 8 ± 2 lobes separated by fine interlobar septa. There is no reduction of lobes with maturity. The pelvis bifurcates at the sinus into primary branches or infundibula which dispatch a secondary branch or infundibulum into every lobe. Interlobar arteries and veins, nerves, fat, and connective tissue generally accompany every secondary infundibulum into its lobe. A major branch of the renal artery may perforate the renal capsule and course to the cortico‐medullary (C‐M) border independently of the secondary infundibulum to that lobe.The number of glomeruli per kidney is approximately 15 × 106. In adults the glomerular mass is 4.9 ± 0.5% of the renal parenchyma and 6.7 ± 0.3% of the cortex. Areae cribrosae occur generally at low papillae. They are the outlets of numerous terminal collecting ducts which may be accompanied by a tubus maximus (T.M.) A T.M. of diameter 1.6 mm and length 10 mm may act as the only substitute for an area cribrosa.Wide anastomoses between the two main renal veins occur within the renal sinus. Intralobar arteries and veins often course right through the outer medulla to and from, respectively, the C‐M border.Conclusions: Anatomically, an elephant's kidneys appear to be able to concentrate urine only moderately. Their kidneys tend to resemble those of the manatee but not of the dugong. © 1995 Wiley‐Liss, Inc.