Contribution to knowledge of the morphogenesis of the nasal apparatus of the fallow deer (Dama dama L.)

As in the red deer, in the fallow deer embryo we found a number of ancestral structures reminiscent of relationships in other mammals, such as paraseptal cartilages, a septum nasi with trabecular widening, a lamina transversalis ant., a cart. ectochoanalis, a capsule wall with a roof and a lateral wall formed of a clearly distinguishable cart. parietotectalis and cart. paranasalis, an ethmoturbinale I projecting a long way rostrally and additionally, in the fallow deer, cart. paraseptales posteriores. I regard the relationship of the cart. alaris inf. to the parietotectal cartilage (or "marginoturbinale") as relatively "primitive"; this may mean that the term "atrioturbinale" is also justified in mammals and that the relevant structure is homologous with the one known by the same name in birds. The specializations found during study of the morphogenesis of the nasal apparatus in the red deer (Slaby 1990b) are accentuated in the fallow deer. The chief ones are the specific rostral processes of the anlage of the nasal septum, which are a significant part of reinforcement of the nostril, the marked widening of the nasal capsule in a lateral direction (so that even the paranasal cartilages have a largely horizontal course), the striking ventrolateral bulge in the nasal capsule at the beginning of the olfactory region and the final resultant decrease in the height (i. e. flattening) of the capsule. This leads to reduction of the frontoturbinalia and their corresponding recesses, which - where they are developed - are oriented more horizontally. The structure of ethmoturbinale I, together with its insertion, is also simplified. As in the corresponding red deer embryo, the paranasal cartilage zone in the anterior part of the olfactory region is strikingly thickened; the frontoturbinalia do not, however, originate (in our stage) by the formation of cavities in the cartilage, but develop as simple processes. A crista semicircularis and foramen epiphaniale and also, as distinct from the red deer embryo, cart. paraseptales posteriores, are clearly discernible. In conclusion, it can therefore be claimed that the morphogenesis of specialized cervid features is accentuated in Dama more than in Cervus and that relationships in the fallow deer represent a further step in specialization, or - if we are speaking of the development of radiations - specialization here has progressed further.     

Morphogenesis of the nasal apparatus of the red deer (Cervus elaphus L.)

Three stages of morphogenesis of the nasal apparatus of the red deer (Cervus elaphus L.) were studied. Many ancestral traits reminiscent of relationships in other mammals and even in reptiles were found, including a cart, ectochoanalis, paraseptal cartilages, the septum nasi and its ventral trabecular enlargement, a lamina transversalis ant., clear separation of the cart, parietotectalis and cart, paranasalis from each other and a crista semicircularis. A maxilloturbinale, was present, but not a nasoturbinale. The main specific features were a completely rostrally localized, peculiar cartilaginous structure in the preseptal space, for which there is as yet no morphological explanation, and pronounced bulging of the cartilaginous wall of the nasal capsule in a ventrolateral direction, level with the rostral region of the olfactory labyrinth (caudally to the aboral end of the maxilloturbinale). In the early stages of morphogenesis, it was found that the ethmoturbinalia might be formed by fusion of the edges of the anlagen of the paranasal cartilage and the lamina orbitonasalis. The structure of the olfactory labyrinth was reminiscent of its organization in the sheep embryo; the recessus frontalis was completed by a series of frontoturbinal recesses and frontoturbinalia, which are poorly developed in the red deer, however. The floor of the caudal part of the nasal capsule was very little developed and there was no cart, paraseptalis post.     

Ontogenetic and phylogenetic transformations of the vomeronasal complex and nasal floor elements in marsupial mammals

Histological sections and three-dimensional reconstructions of section-series were used to document the anatomy of the vomeronasal complex and other aspects of the ethmoidal region in representatives of 13 families and six orders of marsupial mammals, including for the first time Microbiotheria. The changes during growth of several features were examined in ontogenetic series. Marsupials are very conservative in comparison with eutherians regarding the vomeronasal complex. All have a vomeronasal organ and a nasopalatine duct, have no nasopalatine duct cartilage, have no (or just an incipient) palatine cartilage, and the overall construction of the nasal floor is uniform across species. Most features examined show a high degree of homoplasy (e.g. presence of glandular ridges, isolated dorsal process of the paraseptal cartilage), and their systematic value is confined to low taxonomic levels. Significant ontogenetic changes occur in features usually discussed in the systematic/taxonomic literature. Amongst the didelphids examined, Caluromys philander shows several autapomorphies. It is hypothesized that the opening of the VNO into the upper end of the nasopalatine duct was present in the marsupial groundplan. Most marsupials have a large and horizontal anterior transverse lamina, the plesiomorphic condition, which becomes oblique in diprotodontians. Some features are autapomorphies of well-supported monophyletic groups of marsupials, e.g. the conspicuous internasal communication of perameliformes and the 'tube-like' or ring-shaped paraseptal cartilage of vombatiformes. An outer bar joining the middle (and not the dorsal-most portion) of the paraseptal cartilage characterizes Australasian marsupials and Dromiciops, with the exclusion of perameliformes, and evolved independently in Caluromys philander.     

Developmental morphology of the solum nasi in the mouse lemur (Microcebus murinus)

The solum nasi of Microcebus murinus is characterized by the presence of a zona annularis, continuity between the anterior transverse lamina and the paraseptal cartilage, a continuous paraseptal cartilage, a palatine cartilage and a posterior transverse lamina. It lacks a fibula reuniens and possibly a cartilage of the nasopalatine duct as well as a palatine papillary cartilage. The morphology in M. murinus closely resembles that seen in Tupaia and Galago. This affinity results from the retention of primitive traits. However, Galago is reported to lack a zona annularis, thus displaying a specialization not shared with M. murinus. Therefore, the zona annularis provides a useful trait for distinguishing between the ontogenies of M. murinus and Galago.     

Late embryonic development of the vomeronasal complex of the cat (Felis silvestris)

An examination of 2 feline embryos in different stages of development (overall length 60 and 115 mm respectively) reveals a well developed vomeronasal complex in each case. Jacobson's Organs embedded within the paraseptal cartilage form long blind tubes at the base of the septum nasi. The cartilage is caudally tub-shaped and embraces rostrally completely the organ over a considerable length. In this manner a long, nearly tunnel-like tube is formed which represents a modified form of the original outer bar and which has not been described so far in cats. It stretches rostro-ventrally across the branching region of the paraseptal cartilage as far as the mouth of Jacobson's Organ. The dorsal branch of the cartilago paraseptalis on the other hand forms a vertically oriented strip which connects to the lamina transversalis anterior. The ductus nasopalatinus passing through the palate is laterally supported by a cartilago ductus nasopalatini which rostrally to the mouth of Jacobson's Organ forms a unified element with the ventral branch of the cartilago paraseptalis. In the case of the younger cat embryo, this cartilago ductus nasopalatini is yet weakly developed. The ductus nasopalatini of the embryos studied are in an amazingly retarded state of development. The ductus, which are blocked in the early stages of the embryonic development during secondary palate formation, form predominantly solid strands of epithelium. By dissolving the cemented epithelium, the ductus are open. But even in the case of the older embryo of the cat, this process is not completed yet. The short duct connecting Jacobson's Organ with the ductus nasopalatinus is also still closed in both embryos. Such cemented sections of epithelium of the younger embryo reveals an interesting relation between the ductus nasopalatinus and the ductus nasolacrimalis which so far has not been pointed out for mammals. From the point of view of phylogenetics, the locally specialized vomeronasal complex of cats exhibits all the criteria of a progressive development of characteristics.     

The early development of Jacobson's organ in the nasal cavity of the rat before the inception of the secondary palatal development

The early development of Jacobson's organ was studied by means of a series of embryos of the rat which were of various ages and exactly dated. Already at the youngest stage of those rats, the nasal cavity is just an open groove, the organ is a thickened epithelial layer at the medial nasal process. Only 15 h later, while the nasal grooves start to close from caudal to rostral, Jacobson's organ has acquired the shape of a deep, long cleft, situated within the broad nasal opening. On the 13th d of fetal life, a complete, caudally closed nasal cavity appears. By the means of fundamental growth changes, the already well developed organ has become shifted to a more caudal position and lies now above the primary palate. A shorter caudal part of the still cleft-like organ just starts to close itself thus forming its typical tube-like structure. Moreover strong nerve bundles running from Jacobson's organ to the brain indicate that in the meantime a sensory epithelium can be distinguished. Up to the 15th d of development, the tube-forming process of Jacobson's organ is completed. Parallel to this procedure, the surrounding nasal cavity acquires a caudal apertura nasalis interna by the rupture of the membrana bucconasalis while Jacobson's organ still lies above the rostral primary palate. Primary in the medial, somewhat later in the lateral part of the nasal cavity, first outlines of cartilage appear, visible as dense cell formations. Together with this, the paraseptal cartilage, in these stages closely connected to the septal cartilage, develops quite early. Between the 14th and 15th d of its fetal life, the flat, tube-formed Jacobson's organ of the rat gets turned from a primary horizontal into a vertical position, which brings its sensory epithelium to the medial side. It is assumed that this happens for functional reasons. Because of the obviously early and progressive development of Jacobson's organ within that of the nasal cavity, it seems to be probable that already the origin of the nose, the olfactory placodes, are determined in the directions both of the nasal cavity and of Jacobson's organ. Furthermore the results demonstrate an early preferential development of Jacobson's organ in comparison to that of the surrounding nasal cavity.     

Ontogeny of the partial secondary wall of the otoccipital region of the endocranium in prehatching Alligator mississippiensis (Archosauria, Crocodylia)

The ontogeny of the posterior otic and anterior occipital portions of the neural endocranium of prehatching Alligator mississippiensis was investigated by reconstruction from sectioned material. In Stage 6 of this species, in which the endochondral ossification of the otoccipital region of the neural endocranium is only in its very early stage, two bony outgrowths-laminae-are present at the external wall of the posterior portion of the neural endocranium. The anterior lamina arises from the external surface of the basal plate at the level of the posterior margin of the subcapsular process; the posterior lamina arises from the external surface of that portion of the pila occipitalis that forms the posteroventral wall of the metotic fissure. During ontogeny, both laminae lying in the anteroposterior sequence ossify in membrane, fuse together, grow laterodorsally, and fuse with the lateral wall of the lateral semicircular canal and the crista parotica. This lamina forms a new, secondary wall enclosing the posterior section of the otic capsule and contains the large external jugular foramen (or foramen vagi) in its basal portion. The laminae, designated lamina juxtaotica anterior and posterior (lamina juxtaotica when fused together), have not been recorded previously in crocodylians and are absent in all other Recent reptiles. From the functional point of view, the juxtaotic lamina 1) forms the margins of the external jugular foramen, and 2) forms the floor of the posterior section of the Eustachian tube. In birds, the structure called the metotic cartilage, which arises in ontogeny as an independent element, has a similar position as the juxtaotic lamina. However, the two structures differ in their developmental origins and their relation to the Eustachian tube and the ramus hyomandibularis of the facialis nerve. Moreover, there is no external jugular foramen in birds.     

Morphogenesis of the cranium of Cavia porcellus L. II: Comparative part and literature

The development of the chondrocranium of Cavia porcellus is compared to those of other rodents. The tectum posterius of the investigated rodents is orientated vertically. This position is functionally caused by the attachment of the muscles of the neck and shoulder girdle. The paracondylar process is a typical feature of rodents although absent in Mesocricetus. Only in Cavia and Tatera, the connection between the lamina supraoccipitalis and the auditory capsule-the supraoccipitocapsular commissure-is missing. Youssef's (1966) generalization that the course of the notochord in rodents is of transbasal type cannot be confirmed. In Cavia, the auditory capsule is connected with the occipital region only by the exoccipitocapsular commissure. The connection between auditory capsule and basal plate is established by the alicochlear and the anterior basicapsular commissures. In comparison to other rodents, the number of commissures in Cavia is reduced. In rodents, there is always a subarcuate fossa which in later stages of development is filled out by the flocculus cerebelli. In contrary to Rajtova's (1972a) statement, Cavia shows a suprafacial commissure as all mammals do (Reinbach 1952). As the tegmen tympani is absent in Otomys and Erethizon, it is not a typical rodent feature. The carotid foramen is well developed in Cavia but the internal carotid artery obliterates until the 25 mm CRL-stage. In embryonic rodents, the ala temporalis may have a foramen ovale but not a foramen rotundum. During ontogeny rodents show the ala hypochiasmatica for the attachment of the straight muscles of the eyeball. In Cavia the ala hypochiasmatica develops independently and fuses with the postoptic root of the ala orbitalis in later stages. In myomorphs and sciumorphs, the orbitoparietal and orbitonasal commissures are present. Only in caviomorphs this part of the primary sidewall of the skull is uncomplete. Erethizon, however, shows an orbitonasal commissure whereas in Cavia both commissures are missing. In this respect the guinea-pig resembles the condition of primates. There is no interorbital septum in rodents. The nasal capsule of rodents contains 1 atrioturbinal, 1 maxilloturbinal, 1 nasoturbinal, and at least 3 ethmoturbinals. Due to the strong development of the alveoli of the incisors, the maxilloturbinale is flected in the caviomorphs. The epiphanial foramina are present. The lamina transversalis anterior is continuous with the nasal septum so that there is a complete zona anularis in rodents. The paraseptal cartilages are continuous with the lamina transversalis anterior but not with the lamina transversalis posterior.(ABSTRACT TRUNCATED AT 400 WORDS)     

Comparative macro- and microscopic anatomy of the nasal cavity of European insectivores]

The topography of the nasal fossa and its epithelium were studied in 4 European Insectivores, Sorex araneus L., Crocidura russula (Hermann), Talpa europaea L. and Erinaceus europaeus L. The following results were obtained: 1. The length of the nasal capsules is in relation to the length of the head in all 4 species the same. 2. The noses of all forms studies, except E. europaeus are very similar because of the trunk-shaped pars anterior nasi. 3. The numbers of turbinals are constant. 4. Of all turbinals the atrio-turbinal is ventrally the rostral one, and in the shrews it is considerably longer than in E. europaeus and T. europaea. 5. There is a maxillo-turbinal caudal of the atrio-turbinal. Both of these turbinals can be found separated by an incisura atrio-maxillo-turbinalis in T. europaea and the shrews. In E. europaeus the skeleton of the 2 turbinals is bridged by a fold of mucous membrane. 6. The maxillo-turbinal is bilamellar in T. europaea and the shrews, with each of the laminae rolled up in opposite direction. The surface of the maxillo-turbinal of E. europaeus is increased enormously by means of secondary folds. 7. The naso-turbinal begins almost at the tip of the nose and approaches the lamina cribrosa, where it disappears. One can discern 3 differently shaped parts of the naso-turbinal: Crus orale, crus intermedium and crus aborale. The nasoturbinal originates out of 2 different structures (the crus orale of the naso-turbinal and the lamina semicircularis) which are ontogenetically different, however, they have become fused during ontogeny, thus forming a structure which seems to be homogenous. 8. There are 3 ethmo-turbinals. The 1st ethmo-turbinal is the largest one and its free anterior tip is found in the intermediate part of the nasal fossa. Its epi-turbinal is an accessory lamella found in the aboral part of the first ethmoturbinal. Except in S. araneus it always appears in paraseptal views between the ethmo-turbinal I and II. 9. There are 3 ecto-turbinals. 2 ecto-turbinals are situated between the naso-turbinal and the ethmo-turbinal I, whereas the 3rd ecto-turbinal appears between ethmo-turbinal I and II. 10. There are 3 recesses of the lateral parts of the nasal fossa: The recessus frontalis anterior is found rostral-dorsally of the pars intermediate of the nasal fossa. The recessus frontalis posterior communicates with the former, but is located caudal of it. The 3rd recessus sphenoidalis is actually a subcerebral niche of the nasal fossa in the os sphenoidale. 11. There is only one pneumatic cavity in Insectivores, the sinus maxillaris. 12. The nasal fossa can be divided into a regio vestibularis, regio respiratoria and regio olfactoria. The epithelium of the nasal fossa is similar in all forms studied. 13. The anterior part of the oral regio vestibularis is outlined by keratinized epithelium; posteriorly, by loosing its stratum corneum, it changes into unkeratinized pseudostratified epithelium. 14...     

Immunochemical and mechanical characterization of cartilage subtypes in rabbit.

Cartilage is categorized into three general subgroups, hyaline, elastic, and fibrocartilage, based primarily on morphologic criteria and secondarily on collagen (Types I and II) and elastin content. To more precisely define the different cartilage subtypes, rabbit cartilage isolated from joint, nose, auricle, epiglottis, and meniscus was characterized by immunohistochemical (IHC) localization of elastin and of collagen Types I, II, V, VI, and X, by biochemical analysis of total glycosaminoglycan (GAG) content, and by biomechanical indentation assay. Toluidine blue staining and safranin-O staining were used for morphological assessment of the cartilage subtypes. IHC staining of the cartilage samples showed a characteristic pattern of staining for the collagen antibodies that varied in both location and intensity. Auricular cartilage is discriminated from other subtypes by interterritorial elastin staining and no staining for Type VI collagen. Epiglottal cartilage is characterized by positive elastin staining and intense staining for Type VI collagen. The unique pattern for nasal cartilage is intense staining for Type V collagen and collagen X, whereas articular cartilage is negative for elastin (interterritorially) and only weakly positive for collagen Types V and VI. Meniscal cartilage shows the greatest intensity of staining for Type I collagen, weak staining for collagens V and VI, and no staining with antibody to collagen Type X. Matching cartilage samples were categorized by total GAG content, which showed increasing total GAG content from elastic cartilage (auricle, epiglottis) to fibrocartilage (meniscus) to hyaline cartilage (nose, knee joint). Analysis of aggregate modulus showed nasal and auricular cartilage to have the greatest stiffness, epiglottal and meniscal tissue the lowest, and articular cartilage intermediate. This study illustrates the differences and identifies unique characteristics of the different cartilage subtypes in rabbits. The results provide a baseline of data for generating and evaluating engineered repair cartilage tissue synthesized in vitro or for post-implantation analysis.     

Chin augmentation with nasal osteocartilaginous graft

The use of the nasal hump removed during rhinoplasty was described by Aufricht in 1934 and 1958. In the past 10 years, the author has been using a similar technique but with significant variations. Before beginning the rhinoplasty surgery, the author dissects, through a submental incision, a subperiosteal mental pocket. Then, the osteocartilaginous nasal hump is removed; once the mucoperiosteum/mucoperichondrium is meticulously dissected, the nasal hump is tailored to achieve a mental form and the removed alar cartilage, nasal spine, or septal cartilage is used to fill or supplement the concavities of the hump. This report includes a total of 36 cases, 10 of which were controlled after 3 to 8 years of implantation by tridimensional computed tomography, from which the author observed an osteointegration with the mandibular bone and no reabsorption of the grafts or alteration of the structure of this bone. The patients revealed a high degree of satisfaction, and during the clinical examination, the author could not observe or palpate any distortion of the shape or projection of the chin. None of the grafts needed review or removal. This simple, fast procedure is a very good alternative for patients with some form of microgenia or when patients and surgeons are not likely to use alloplastic implants.     

Histological analysis of the nasal roof cartilage in a neonate sperm whale (Physeter macrocephalus – Mammalia, Odontoceti)

The nasal roof cartilage of a neonate sperm whale (Physeter macrocephalus) was examined by gross dissection and routine histology. This cartilage is part of the embryonic Tectum nasi and is a critical feature in the formation of the massive sperm whale forehead. In neonates as well as in adults, the blade-like nasal roof cartilage extends diagonally through the huge nasal complex from the bony nares to the blowhole on the left side of the rostral apex of the head. It accompanies the left nasal passage along its entire length, which may reach several meters in adult males. The tissue of the nasal roof cartilage in the neonate whale shows an intermediate state of development. For example, in embryos and fetuses, the nasal roof cartilage consists of hyaline cartilage, but in adult sperm whales, it also includes elastic fibers. In our neonate sperm whale, the nasal roof cartilage already consisted of adult-like elastic cartilage. In addition, the active or growing, layer of the perichondrium was relatively thick compared to that of fetuses, and a large number of straight elastic fibers that were arranged perpendicularly to the long axis of the nasal roof cartilage were present. These neonatal features can be interpreted as characteristics of immature and growing cartilaginous tissue. An important function of the nasal roof cartilage may be the stabilization of the left nasal passage, which is embedded within the soft tissue of the nasal complex. The nasal roof cartilage with its elastic fibers may keep the nasal passage open and prevent its collapse from Bernoulli forces during inhalation. Additionally, the intrinsic tension of the massive nasal musculature may be a source of compression on the nasal roof cartilage and could explain its hyaline character in the adult. In our neonate specimen, in contrast, the cartilaginous rostrum (i.e., mesorostral cartilage) consisted of hyaline cartilage with an ample blood supply. The cartilaginous rostrum does not change its histological characteristics during development, but its function in adults is still not understood.     

The development of the chondrocranium of the lacertid lizard,Acanthodactylus boskiana

The trabeculae cranii are at first quite separate from each other, after few days their anterior two fifths are connected by a trabecular plate which is obliterated throughout development. The paired origin of the parachordal plate is not observed. The fused posterior orbital cartilages chondrify in the form of a wide short plate, traversed by the oculomotor and trochlear nerves. The basicranial fenestra and fenestra ovalis are formed by the degeneration of pre-existing cartilage. The cochlear portion is completely fused with the parachordal plate from the very beginning. The elements of the pterygoquadrate are fused together. The quadrate and Meckel's cartilage are in close contact from the very beginning. While the lower part of the interorbital septum is derived from the trabecula communis, its upper part is derived from the anterior orbital cartilages. The lateral parts of the fused posterior orbital cartilages give rise to most of the taeniae and pilae of the orbitotemporal region. There is only one commissure between the auditory capsule and parachordal plate. A cartilaginous connection between the distal portion of the columella auris and ceratohyal persists for some time. The parietotectal and paranasal cartilages are fused together from the very beginning. The processus paroticus originates from the columella auris. In the fully formed stage the notochord is completely embedded in the occipital condyle. The union between the condyle and odontoid process persists. The auditory capsules and occipital arches contribute to the formation of the tectum synoticum plus posterius. The prefacial commissure and facial foramen lie in front of the cochlear portion. The columella auris possesses a processus internus (connected with the quadrate), but the processes a dorsalis has completely disappeared. The orbitotemporal region is quite complete. A medial fenestra is formed in the planum supraseptale. A fenestra is observed in each of the interorbital and nasal septa. The lamina transversalis anterior is fused with the parietotectal cartilage. A complete zona annularis is present. The outer wall of the paranasal cartilage is perforated by a large fenestra lateralis. The parietotectal and paranasal cartilages and the posterior process of the lamina transversalis anterior contribute to the formation of the concha nasalis. There is a contact between the planum antorbitale and nasal septum. The pterygoid process has disappeared. The common characters of the lacertid chondrocranuium are deduced.     

A new technique in nasal-tip reduction surgery.

This article presents a technique for the reduction of the overprojected nasal tip with a proportional reduction of the nostril-margin circumference. To achieve these reductions, a modified open rhinoplasty technique is used, which is unique in that it involves the total transection of the columella through the medial crura of the alar cartilage. The alar cartilage is raised with the flap.The technique was first developed and introduced by the senior author (R.A.S.) 25 years ago and has since been refined through the execution of several thousand rhinoplasties. The results continue to be consistent and pleasing from both the patients' and the surgeon's points of view.     

Gene and protein expressions of type I collagen are regulated tissue-specifically in rat hyaline cartilages in vivo

The present study was designed to investigate how rat hyaline cartilages at various sites in vivo express the gene and protein of type I collagen using in situ hybridization and immunohistochemistry. The gene of pro alpha 1(I) collagen was expressed by chondrocytes in articular cartilage, and the protein of type I collagen was identified in the cartilage matrix. In contrast, growth plate cartilage expressed the gene of pro alpha 1(I) collagen, but no protein of type I collagen. Neither gene nor protein of type I collagen was expressed in cartilages of trachea and nasal septum. The present study suggested that expression of type I collagen in hyaline cartilages may be regulated tissue-specifically at gene and/or protein levels.     

Interaction between proteoglycan subunit and type II collagen from bovine nasal cartilage, and the preferential binding of proteoglycan subunit to type I collagen.

We studied the interaction of proteoglycan subunit with both types I and II collagen. All three molecular species were isolated from the ox. Type II collagen, prepared from papain-digested bovine nasal cartilage, was characterized by gel electrophoresis, amino acid analysis and CM-cellulose chromatography. By comparison of type I collagen, prepared from papain-digested calf skin, with native calf skin acid-soluble tropocollagen, we concluded that the papain treatment left the collagen molecules intact. Interactions were carried out at 4 degrees C in 0.06 M-sodium acetate, pH 4.8, and the results were studied by two slightly different methods involving CM-cellulose chromatography and polyacrylamide-gel electrophoresis. It was demonstrated that proteoglycan subunit, from bovine nasal cartilage, bound to cartilage collagen. Competitive-interaction experiments showed that, in the presence of equal amounts of calf skin acid-soluble tropocollagen (type I) and bovine nasal cartilage collagen (type II), proteoglycan subunit bound preferentially to the type I collagen. We suggest from these results that, although not measured under physiological conditions, it is unlikely that the binding in vivo between type II collagen and proteoglycan is appreciably stronger than that between type I collagen and proteoglycan.     

Characterization of glycosaminoglycans from human normal and scoliotic nasal cartilage with particular reference to dermatan sulfate.

The composition and the distribution of glycosaminoglycans (GAGs) present in normal human nasal cartilage (HNNC), were examined and compared with those in human scoliotic nasal cartilage (HSNC). In both tissues, hyaluronan (HA), keratan sulfate (KS) and the galactosaminoglycans (GalAGs)--chondroitin sulfate (CS) and dermatan sulfate (DS)--were identified. The overall GAG content in HSNC was approx. 30% higher than the HNNC. Particularly, a 114% increase in HA, and 46% and 86% in KS and DS, respectively, was recorded. CS was the main type of GAG in both tissues with no significant compositional difference. GalAG chains in HSNC exhibited an altered disaccharide composition which was associated with significant increases of non-sulfated and 6-sulfated disaccharides. DS, which was identified and quantitated for the first time in HNNC and HSNC, contained low amounts of iduronic acid (IdoA), 18% and 28% respectively. In contrast to other tissues, where IdoA residues are organized in long IdoA rich repeats, the IdoA residues of DS in human nasal cartilage seemed to be randomly distributed along the chain. DS chains in HSNC were of larger average molecular size than those from HNNC. These results clearly indicate the GAG content and pattern in both HNNC and HSNC and demonstrate that scoliosis of nasal septum cartilage is related to quantitative and structural modifications at the GAG level.     

Anatomy of the external nasal nerve

After rhinoplasty, many patients report numbness of the nasal tip. This is primarily because of injury to the external nasal nerve. It is imperative that surgeons performing rhinoplasty be familiar with the anatomy and the common variations of this nerve. Therefore, the purpose of this study was to present an anatomical study of the external nasal nerve. Twenty external nasal nerves were examined by dissecting 10 fresh cadaver noses within 48 hours of death. On dissection, the exit of the nerve between the nasal bone and upper lateral cartilage was identified. The distance from the point of exit to the midline of the nose and the size of the nerve were measured. The course and the running plane of the nerve were investigated. The nerve branchings were also classified into three types: type I, only one nerve without any branch; type II, one nerve proximally and then splitting into two main branches at the intercartilaginous junction; and type III, two main branches from the point of exit. The point of exit of the external nasal nerve from the distal nasal bone was located 6.5 to 8.5 mm (7.3 +/- 0.6 mm) lateral to the nasal midline. The average diameter of the nerve at the point of exit was 0.35 +/- 0.036 mm. Most of the nerves (95 percent) passed through the deep fatty layer directly under the nasal superficial musculoaponeurotic layer, all the way down to the alar cartilages. In terms of the branching type, type I was observed in 10 of 20 nerves (50 percent), type II was observed in six of 20 (30 percent), and type III was seen in four of 20 (20 percent). On the basis of the results of this study, the following precautions are suggested during a rhinoplasty to minimize the chance of injury to this nerve. First, it is best to avoid deep intercartilaginous or intracartilaginous incisions so that the deep fatty layer is not invaded and the dissection is maintained directly on the surface of the cartilage (deep to the nasal superficial musculoaponeurotic layer). Second, dissection at the junction of the nasal bone and upper lateral cartilage area of one side should be limited to within 6.5 mm from the midline. Lastly, when the nasal dorsum is augmented by an onlay graft, implants or grafts less than 13 mm wide at the rhinion level should be used.     

Primary correction of the unilateral cleft lip nose: a 15-year experience

This paper reviews a 15-year personal experience based on 400 unilateral cleft nasal deformities that were reconstructed using a method that repositions the alar cartilage by freeing it from the skin and lining and shifts it to a new position. The rotation-advancement lip procedure facilitates the exposure and approach to the nasal reconstruction. The nasal soft tissues are transected from the skeletal base, reshaped, repositioned, and secured by using temporary stent sutures that readapt the alar cartilage, skin, and lining. The nasal floor is closed and the ala base is positioned to match the normal side. Good subsequent growth with maintenance of the reconstruction has been noted in this series. The repair does not directly expose or suture the alar cartilage. Improvement in the cleft nasal deformity is noted in 80 percent of the cases. Twenty percent require additional techniques to achieve the desired symmetry. This method has been used by the author as his primary unilateral cleft nasal repair and has been taught to residents and fellows under his direction with good results. This technique eliminates the severe cleft nasal deformity seen in many secondary cases.     

Signalling via type IA and type IB bone morphogenetic protein receptors (BMPR) regulates intramembranous bone formation, chondrogenesis and feather formation in the chicken embryo

Bone morphogenetic proteins (BMPs) signal via complexes of type I and type II receptors. In this study, we mapped the expression of type IA, type IB and type II receptors during craniofacial chondrogenesis and then perturbed receptor function in vivo with retroviruses expressing dominant-negative or constitutively active type I receptors. BmprIB was the only receptor expressed within all cartilages. BmprIA was initially expressed in cartilage condensations, but later decreased within cartilage elements. BmprII was expressed at low levels in the nasal septum and prenasal cartilage and at higher levels in other craniofacial cartilages. The maxillary prominence, which gives rise to several intramembranous bones, expressed both type I receptors. Misexpression of dnBMPRIB decreased the size of cartilages and bones on the treated side. In contrast, dnBMPRIA had no effect on the skeletal phenotype. The phenotypes of caBMPRIA and caBMPRIB were similar; both led to overgrowth of cartilage elements, thinner bones with fewer trabeculae and inhibition of feather development. Infection with constitutively active viruses resulted in ectopic expression of Msx1, Msx2 and Fgfr2 throughout the maxillary mesenchyme. These data suggest that the pattern of trabeculation in membranous bones derived from the maxillary prominence was related to the change in expression pattern and that Msx and Fgfr2 genes were downstream of both type I BMP receptors. We conclude that the requirement for the type IB is greater than for the type IA receptor but, when active, both receptors play similar roles in regulating bone, cartilage and feather formation in the skull.