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The skeleton of the upper third of the face is seldom considered as an area for aesthetic improvement. The author reports his experience with alteration of the skeleton of the forehead by recontouring or augmenting for aesthetic purposes. Also the experience with subperiosteal face lifts performed through coronal incisions is reported.
The plasma membrane of nucleated erythrocytes contains a microtubular marginal band which appears to be associated with the plasma membrane skeleton. In this report, we identify two families of cytoskeletal proteins which may be involved in such an association. These proteins, of molecular mass 78 kDa and 48 kDa on SDS-PAGE, are shown to bind tubulin based on a 125I-labeled tubulin binding assay. Solubilization of isolated chicken erythrocyte plasma membranes in Triton X-100 shows that these proteins centrifuge with the pellet, indicating that they are bound to the membrane skeleton. Finally, immunofluorescence studies using antisera raised against the 78 kDa and 48 kDa proteins show that they colocalize with the marginal band in intact cells. Colocalization of cytoskeletal tubulin-binding proteins with the marginal band favors a hypothesis suggesting that the 78 kDa and 48 kDa proteins are involved in the association of the two molecular superstructures.
One hundred patients with recently acquired, externally visible mandibular deformity and no history of previous extraarticular mandible fracture were selected for retrospective analysis. All had been investigated clinically and with radiography, tomography, and high-field surface-coil MR imaging to determine the presence or absence and extent of temporomandibular joint degeneration. Temporomandibular joint degeneration was found in either one or both joints of each patient studied. Chin deviation was always toward the smaller mandibular condyle or more diseased joint, and many patients either complained of or exhibited malocclusion, often manifested by unstable or fluctuating occlusion disturbances. Three radiologically distinct forms of degenerative vs adaptive osteocartilaginous processes--(1) osteoarthritis, (2) avascular necrosis, and (3) regressive remodeling--involving the mandibular condyle and temporal bone were identified in joints most often exhibiting meniscus derangement. Osteoarthritis and avascular necrosis of the mandibular condyle and temporal bone were generally associated with pain, mechanical joint symptoms, and occlusion disturbances. Regressive remodeling was less frequently associated with occlusion disturbances, despite remodeling of the facial skeleton, and appears to result from regional osteoporosis. Forty patients (52 joints) underwent open arthroplasty procedures, including either meniscectomy or microsurgical meniscus repair, at which time major radiologic diagnoses were confirmed. Surgical and pathologic findings included meniscus displacement, disk degeneration, synovitis, joint effusion, articular cartilage erosion, cartilage healing/fibrosis, cartilage hypertrophy, osseous sclerosis, osteophyte formation, osteochondritis dissecans, localized or extensive avascular necrosis, and decreased mandibular condyle mass and vertical dimension. We conclude that temporomandibular joint degeneration is the principal cause of both acquired facial skeleton remodeling and unstable occlusion in patients with intact dentition and without previous mandible fracture.
Movements, manifest as changes in cell arrangements and shape, are an integral part of metazoan development. The molecular basis of such movements is only now being understood. Drosophila offers an excellent opportunity to apply powerful classical and modern molecular genetic methods to the analysis of movements during development. Moreover, the genes that contribute to pattern formation in fly development are under intense investigation. The future promises to illuminate how such genes regulate the structure and function of the membrane skeleton. This review is a progress report on our current understanding of the membrane skeleton in Drosophila.
In the analysis of laryngeal anomalies in 30 selected phoniatric patients by CT examination, 2 atavisms of the laryngeal skeleton were found. The ventral enclosure of the thyroid cartilage by the hyoid bone presents an inhibition malformation of the laryngeal skeleton with essential reduced vocal ability. The posterior junction between the cornu majus ossis hyoidei and the cornu superius cartilaginis thyroideae is marked by the direct contact of these cornua lacking the ligamentum thyrohyoideum laterale. Both anomalies are characterized by the persistence of the close relation between the hyoid bone and the thyroid cartilage, which normally exists phylogenetically as well as ontogenetically. That could be shown by anatomical sections performed on 4 human newborns in the horizontal plane.
The paper is concerned with a program for data processing of dynamic scintigraphy of the skeleton and skeletal muscles using 99mTc-sodium 1-hydroxy-ethane-1, 1-diphosphonate. Employing gamma-chamber computer the program enables rapid and precise computation of the coefficient of RP elimination from the blood and the coefficients of RP accumulation by the bones and muscle tissue. Based on those coefficients one can make diagnosis and follow the time-course of pathological changes occurring in the skeleton during endocrine diseases.
The experimental conditions ensuring the possibility of isolation of nuclear matrices enriched and non-enriched in transcribed DNA sequences were investigated. It is demonstrated that extraction of nuclease treated nuclei with very low ionic strength solution executed before the high salt extraction destroys the apparent attachment of transcriptionally active DNA to the nuclear skeleton elements. On the contrary RNase treatment of nuclei was found to have no effect on distribution of active genes versus points of DNA attachment to the nuclear skeleton.
On the basis of extensive studies of the literature and of own results the present knowledge about the structure of the membrane skeleton of human erythrocytes is summarized and functional and clinical aspects are described. The spectrins are the centre of interest. Their interconnections, spatial arrangement and association with other components of the membrane are explained in greater detail. With regard to the membrane skeleton questions of erythrocyte shape, membrane integrity, phospholipid asymmetry, distribution of transmembrane proteins and cell deformation are discussed.
Recent emphasis on age-related morbidity addresses the increasing life expectancy of Western countries. Osteopenia is a multi-factorial process affecting a sizeable number of elderly individuals, with bone fractures producing significant morbidity and related mortality. A non-human primate would be a very useful experimental model for the study of age-related osteopenia, if it could be shown that it is similarly afflicted by age and if non-invasive methods utilized among humans could give a valid estimation of bone mineral content in the animal. Our previous studies utilizing SPA (single-photon absorptiometry) suggest age-related decrease in BMC (bone mineral content) among rhesus macaque skeletons, similar to that observed in humans. The present studies were done in order to further validate the utilization of bone densitometry (SPA) in the rhesus macaque, comparing their BMC and bone density (BD) with the size and weight of their corresponding bones. Both radii and the right femur of 102 adult rhesus monkey skeletons (5 to 23 years old), were obtained from the Caribbean Primate Research Center (CPRC) Skeletal Collection. There were 55 females and 47 males. Bone parameters were obtained using a Norland Digital Bone Densitometer, model 2780 at 2 scanning sites: distal 1/3 of radii and proximal 1/3 of femurs. Bone lengths (cm) and weights (gm) were compared and correlated with densitometric parameters. Excellent correlations were consistently found, with r values 0.74 to 0.96 and p less than 0.0001. Thus it appears that SPA at distal 1/3 radius or proximal 1/3 femur are a valid estimate of total bone mineral mass in rhesus monkeys.
Based on a comparative morphological study of the axial skeleton in a broader range of "primitive bony fishes" a reevaluation of some characteristic traits of the vertebral column in the African lungfish has been done. The axial skeleton of living dipnoans has to be regarded as reduced from a more complex phylogenetic state and may be neotenic in some respect. The formation of perichordal bony autocentra could be confirmed, at least in one specimen. The well-known invasion of mesenchymal cells into the fibrous sheet of the notochord is interpreted as a rudimentary chordacentric "vertebralization". Also included is an analysis of the peculiar urostyle of lungfishes, its regeneration capacity and its bearing upon the principles of vertebra-formation.
The reasons for using measurements of bone density for further analysis of changes in metabolic bone diseases are pointed out. Besides the easy methods of visual comparison of X-ray images and "microradioscopy", the methods of quantitative radiology are discussed. The X-ray morphometry method is presented, including the new results of measurement of various bones of the skeleton. Structural analysis of spongy and compact bone tissue from the X-ray image using opto electronic image transformation is demonstrated. The techniques of X-ray photodensitometry and isotope-densitometry are explained. The importance of a reproducible calibration standard and the special value of reference systems containing a known concentration of hydroxyapatite are shown. Special information is given regarding the present status of the development of the new technique of quantitative computer tomography (QCT) or computer tomometry with the aid of a solid reference system. This new reference system is constructed from various concentrations of hydroxyapatite in "solid water" (a polyethylene mixture) and is demonstrated in detail. The results of comparing measurements of the 2nd lumbar vertebral body are shown. Finally, the clinical importance of measurements of the "apatite value" of vertebral trabecular bone tissue and of various trabecular areas of the skeleton is emphasized.
During preservation of erythrocytes vesicles are formed, the membranes of which do not contain membrane skeleton components (spectrin, actin). In comparison to the normal erythrocyte membrane (100%) the vesicle membrane exhibits significantly lowered amounts in band 3 protein (14-17%), sialic acid (30-40%), (Ca2+ + Mg2+)ATPase (6%) and (Na+ + K+)ATPase (28%). The losses in band 3 protein, glycophorin A (calculated from the decrease of sialic acid) and in the number of the intramembranous particles correspond to one another. The calmodulin concentration of the vesicles was estimated to be 35% that of the erythrocytes in maximum. The findings indicate a binding of these components to the membrane skeleton. The nature of the binding of the transmembrane proteins as well as the consequences of these results regarding the composition of the intramembranous particles are discussed.
The protein composition of ghosts, inside-out vesicles (IOV), and membrane skeletons (MS) of erythrocytes (RBC) from splenectomized (spx) and nonsplenectomized (non-spx) patients with beta-thalassemia major and beta-thalassemia intermedia was determined. Ghosts from spx thalassemia intermedia patients had a significant increase in their globin content (which was mostly heme reactive) and contained extra polypeptides in the protein 4.2 to 5 and 6-globin areas. The Triton-extracted MS from all of the thalassemic patients showed two major abnormalities: they retained up to twice the amount of protein 3 when compared with controls; they had a significant increase in their globin content, the concentration of which was independent of their protein 3 content. Analysis of the IOV revealed no differences between those prepared from normal controls and those of the patients. MS from spx thalassemia intermedia patients were grossly abnormal when examined by scanning electron microscopy and they exhibited aggregates of material that on transmission electron microscopy suggested the presence of globin precipitates. We propose that, although the integral protein composition, as reflected in the IOV, from severely affected beta-thalassemics is intact, their MS assembly is deranged. The altered skeletal structure of thalassemic RBC could result from attachment of denatured globin to the skeleton components. These abnormalities may contribute to the premature cell death seen in severe beta-thalassemia.
Antitumor activity induced by the oil-attached cell-wall skeleton of Nocardia rubra (N-CWS) was compared with that of the oil-attached cell-wall skeleton of Mycobacterium bovis BCG (BCG-CWS) in syngeneic BALB/c tumor-host systems. In normal BALB/c mice (+/+), N-CWS exhibited stronger suppressive effect on syngeneic Br-1 and MCA tumors than did BCG-CWS. In athymic nude mice (nu/nu), BCG-CWS was as effective as N-CWS for the suppression of growth of such tumors. Suppressive effect of N-CWS treatment appears to be stronger to some extent in +/+ mice than in nu/nu mice. Immune spleen cells obtained from +/+ mice after footpad inoculation of MCA tumor cells mixed with N-CWS were effective in suppressing the MCA tumor growth, although those obtained from mice after inoculation of MCA tumor cells mixed with BCG-CWS did not exhibit a suppressive effect. This antitumor activity of immune spleen cells may be attributed to tumor-specific killer T cells. The differences of antitumor activities induced by these agents were discussed with reference to T-cell dependency and independency.
A 33-year-old woman with asymptomatic osteoporosis sustained a spontaneous middiaphyseal fracture of the femur as the initial sign of Cushing's disease. Subsequently, she incurred a fracture of the ipsilateral hip and both bones of the forearm. All four fractures failed to unite. There were no symptoms of involvement of the axial skeleton. Although axial osteopenia is the most common skeletal finding in hypercortisolism, fractures exclusively limited to the appendicular skeleton should not preclude detailed diagnostic investigations of hypercortisolism.
Protein 4.1 from human erythrocytes formed a complex with band 3 in inside-out erythrocyte membrane vesicles and with soluble peptides derived from the cytoplasmic domain of band 3. Protein 4.1 labeled metabolically with 32P bound saturably to vesicles depleted of endogenous protein 4.1. The soluble cytoplasmic domain of band 3 (43K) competitively displaced approximately 60% of bound 32P-protein 4.1 from reconstituted membrane vesicles. Pretreatment of vesicles with anti-43K similarly inhibited the rebinding of protein 4.1. In solution, 125I-43K formed a complex with protein 4.1 that saturated at 1:1 stoichiometry and migrated as a discrete band when analyzed by nondenaturing polyacrylamide gel electrophoresis. In rate-zonal sedimentation in isotonic salt solutions, protein 4.1 and 43K sedimented as a sharp peak at 4.4 S. In experiments aimed at exploring the role of the protein 4.1-band 3 interaction in the organization of the membrane skeleton, the effect of spectrin was investigated. Spectrin and protein 4.1 formed a complex which co-sedimented in sucrose gradients, but the addition of 43K to preformed spectrin-protein 4.1 complexes resulted in disruption of the complex and co-sedimentation of most of the protein 4.1 with 43K. These results suggest that protein 4.1 can associate with band 3 in the erythrocyte membrane and that this association may modulate the attachment of the membrane skeleton to the membrane.
A membrane skeleton consisting of a structural matrix of spectrin, actin, and band 4.1 linked to band 3 in the fluid bilayer through ankyrin appears to be responsible for many of the material properties of the red cell membrane. In response to externally applied forces, the membrane behaves as a solid, a semisolid, or a liquid, depending on the magnitude and duration of the applied forces. Under physiologic conditions, the normal skeleton permits the red cells to undergo marked reversible deformations as a viscoelastic material. Perturbations of this skeletal assembly, as a result of molecular defects in skeletal components, lead to various altered membrane material properties and altered behavior in the circulation. The altered material properties include increased elastic shear modulus, irreversible membrane flow, or even membrane yield, resulting in cell fragmentation. These alterations in turn lead to changes in cellular deformability either as a result of increased membrane rigidity or decreased surface-area-to-volume ratio, secondary to cell fragmentation. As cellular deformability is one of the major parameters that determines red cell life span, skeletal dysfunction leading to decreases in deformability can account for increased red cell destruction in many congenital and hereditary hemolytic anemias.
The effects of an acidic pH on the membrane skeleton of erythrocyte ghosts has been investigated by negative staining and thin-section methods. At neutral pH the membrane skeleton consisted of 6-7 nm wide filaments uniformly dispersed on the inner membrane surface. At pH 5.0 the filaments fused to form a coarse network with thick strands and large areas of membrane devoid of filaments. These changes were completely reversible in many cells. They can probably account for the clustering of surface anionic sites and membranous particles which occur at a low pH and may play a role in other related events such as the change in shape of the cell and increased membrane stiffness.