Endometrial hyperplasia with loss of APC in a novel population of Lyz2-expressing mouse endometrial epithelial cells

Loss of heterozygosity and promoter hypermethylation of APC is frequently observed in human endometrial cancer, which is the most common gynecological cancer in the US, but its carcinogenic driver status in the endometrial epithelium has not been confirmed. We have identified a novel population of progenitor endometrial epithelial cells (EECs) in mice that express LysM and give rise to approximately 15% of all EECs in adult mice. Lysozyme M (LysM) is a glycoside hydrolase that is encoded by Lyz2 and functions to protect cells from bacteria as part of the innate immune system. Its expression has been shown in a subset of hematopoietic stem cells and in specialized lung and small intestinal epithelial cells. Conditional deletion of Apc in LysM+ EECs results in significantly more epithelial cells compared to wild type mice. At five months of age, the Apc  cKO mice have enlarged uterine horns with pathology that is consistent with endometrial hyperplasia with cystic endometrial glands, non-villous luminal papillae, and nuclear atypia. Nuclear accumulation of β-catenin and ERα, both of which are known to induce endometrial hyperplasia, was observed in the EECs of the Apc  cKO mice. These results confirm that loss of APC in EECs can result in a phenotype similar to endometrial hyperplasia.

In vitro differentiation of human parthenogenetic stem cells into neural lineages

Human parthenogenetic stem cells are derived from the inner cell mass of blastocysts obtained from unfertilized oocytes that have been stimulated to develop without any participation of male gamete. As parthenogenesis does not involve the destruction of a viable human embryo, the derivation and use of human parthenogenetic stem cells does not raise the same ethical concerns as conventional embryonic stem cells. Human parthenogenetic stem cells are similar to embryonic stem cells in their proliferation and multilineage in vitro differentiation capacity. The aim of this study is to derive multipotent neural stem cells from human parthenogenetic stem cells that are stable to passaging and cryopreservation, and have the ability to further differentiate into functional neurons. Immunocytochemistry, quantitative real-time PCR, or FACS were used to confirm that the derived neural stem cells express neural markers such as NES, SOX2 and MS1. The derived neural stem cells keep uniform morphology for at least 30 passages and can be spontaneously differentiated into cells with neuron morphology that express TUBB3 and MAP2, and fire action potentials. These results suggest that parthenogenetic stem cells are a very promising and potentially unlimited source for the derivation of multipotent neural stem cells that can be used for therapeutic applications.

Mechanical contributions to astrocyte adhesion using a novel in vitro model of catheter obstruction

Drainage and diversion of cerebrospinal fluid (CSF) through shunt systems is the most common treatment for hydrocephalus, but complications due to tissue obstruction of the catheter occur in up to 61% of patients. Although shunt systems have undergone limited technological advancements to resist mammalian cell adhesion, there is a need to further reduce adhesion that can exacerbate obstruction. The high intrinsic variability in clinical studies and an inability to predict chronic adhesion of host cells in vitro while maintaining the environmental conditions observed in hydrocephalus have impeded progress. We designed the hydrocephalus shunt catheter bioreactor (HSCB) to measure inflammatory cell adhesion under experimentally manipulated conditions of CSF pressure, pulsation rate, and flow rates. For a 20-h period, astrocytes were perfused through the pulsatile flow system, and adhesion on silicone catheters was recorded. These results were compared with those obtained under static cell culture conditions. Astrocyte adhesion was significantly increased under conditions of increased flow rate (0.25 and 0.30 mL/min), and a trend toward increased adhesion was observed under conditions of elevated pressure and pulsation rate. Because the HSCB represents physiologic conditions more accurately than static cell culture, our results suggest that standard static cell culturing techniques are insufficient to model inflammatory cell adhesion on catheters used in the treatment of hydrocephalus and that changes to the ventricular microenvironment can alter the mechanisms of cellular adhesion. The HSCB represents a relevant test system and is an effective model system for the analysis of cellular adhesion and occlusion of shunt catheters.

Loss of RhoB expression enhances the myelodysplastic phenotype of mammalian diaphanous-related Formin mDia1 knockout mice

Myelodysplastic syndrome (MDS) is characterized by ineffective hematopoiesis and hyperplastic bone marrow. Complete loss or interstitial deletions of the long arm of chromosome 5 occur frequently in MDS. One candidate tumor suppressor on 5q is the mammalian Diaphanous (mDia)-related formin mDia1, encoded by DIAPH1 (5q31.3). mDia-family formins act as effectors for Rho-family small GTP-binding proteins including RhoB, which has also been shown to possess tumor suppressor activity. Mice lacking the Drf1 gene that encodes mDia1 develop age-dependent myelodysplastic features. We crossed mDia1 and RhoB knockout mice to test whether the additional loss of RhoB expression would compound the myelodysplastic phenotype. Drf1^−/−RhoB^−/− mice are fertile and develop normally. Relative to age-matched Drf1^−/−RhoB^+/− mice, the age of myelodysplasia onset was earlier in Drf1^−/−RhoB^−/− animals—including abnormally shaped erythrocytes, splenomegaly, and extramedullary hematopoiesis. In addition, we observed a statistically significant increase in the number of activated monocytes/macrophages in both the spleen and bone marrow of Drf1^−/−RhoB^−/− mice relative to Drf1^−/−RhoB^+/− mice. These data suggest a role for RhoB-regulated mDia1 in the regulation of hematopoietic progenitor cells.

The Wnt co-receptor Lrp6 is required for normal mouse mammary gland development

Canonical Wnt signals are transduced through a Frizzled receptor and either the LRP5 or LRP6 co-receptor; such signals play central roles during development and in disease. We have previously shown that Lrp5 is required for ductal stem cell activity and that loss of Lrp5 delays normal mammary development and Wnt1-induced tumorigenesis. Here we show that canonical Wnt signals through the Lrp6 co-receptor are also required for normal mouse mammary gland development. Loss of Lrp6 compromises Wnt/beta-catenin signaling and interferes with mammary placode, fat pad, and branching development during embryogenesis. Heterozygosity for an inactivating mutation in Lrp6 is associated with a reduced number of terminal end buds and branches during postnatal development. While Lrp6 is expressed in both the basal and luminal mammary epithelium during embryogenesis, Lrp6 expression later becomes restricted to cells residing in the basal epithelial layer. Interestingly, these cells also express mammary stem cell markers. In humans, increased Lrp6 expression is associated with basal-like breast cancer. Taken together, our results suggest both overlapping and specific functions for Lrp5 and Lrp6 in the mammary gland.

Myeloproliferative Defects following Targeting of the Drf1 Gene Encoding the Mammalian Diaphanous–Related Formin mDia1

Rho GTPase-effector mammalian diaphanous (mDia)-related formins assemble nonbranched actin filaments as part of cellular processes, including cell division, filopodia assembly, and intracellular trafficking. Whereas recent efforts have led to thorough characterization of formins in cytoskeletal remodeling and actin assembly in vitro, little is known about the role of mDia proteins in vivo. To fill this knowledge gap, the Drf1 gene, which encodes the canonical formin mDia1, was targeted by homologous recombination. Upon birth, Drf1+/- and Drf1-/- mice were developmentally and morphologically indistinguishable from their wild-type littermates. However, both Drf1+/- and Drf1-/- developed age-dependent myeloproliferative defects. The phenotype included splenomegaly, fibrotic and hypercellular bone marrow, extramedullary hematopoiesis in both spleen and liver, and the presence of immature myeloid progenitor cells with high nucleus-to-cytoplasm ratios. Analysis of cell surface markers showed an age-dependent increase in the percentage of CD11b+-activated and CD14+-activated monocytes/macrophages in both spleen and bone marrow in Drf1+/- and Drf1-/- animals. Analysis of the erythroid compartment showed a significant increase in the proportion of splenic cells in S phase and an expansion of erythroid precursors (TER-119+ and CD71+) in Drf1-targeted mice. Overall, knocking out mDia1 expression in mice leads to a phenotype similar to human myeloproliferative syndrome (MPS) and myelodysplastic syndromes (MDS). These observations suggest that defective DRF1 expression or mDia1 function may contribute to myeloid malignancies and point to mDia1 as an attractive therapeutic target in MDS and MPS.

T Cell Responses in Mammalian Diaphanous-related Formin mDia1 Knock-out Mice

Activated T cells rapidly assemble filamentous (F-) actin networks in response to ligation of the T cell receptor or upon interaction with adhesive stimuli in order to facilitate cell migration and the formation of the immune synapse. Branched filament assembly is crucial for this process and is dependent upon activation of the Arp2/3 complex by the actin nucleation-promoting factor Wiskott-Aldrich Syndrome protein (WASp). Genetic disruption of the WAS gene has been linked to hematopoietic malignancies and various cytopenias. Although the contributions of WASp and Arp2/3 to T cell responses are fairly well characterized, the role of the mammalian Diaphanous (mDia)-related formins, which both nucleate and processively elongate non-branched F-actin, has not been demonstrated. Here, we report the effects on T cell development and function following the knock out of the murine Drf1 gene encoding the canonical formin p140mDia1. Drf1(-/-) mice develop lymphopenia characterized by diminished T cell populations in lymphoid tissues. Consistent with a role for p140mDia1 in the regulation of the actin cytoskeleton, isolated Drf1(-/-) splenic T cells adhered poorly to extracellular matrix proteins and migration in response to chemotactic stimuli was completely abrogated. Both integrin and chemokine receptor expression was unaffected by Drf1(-/-) targeting. In response to proliferative stimuli, both thymic and splenic Drf1(-/-) T cells failed to proliferate; ERK1/2 activation was also diminished in activated Drf1(-/-) T cells. These data suggest a central role for p140mDia1 in vivo in dynamic cytoskeletal remodeling events driving normal T cell responses.

Isolation of large numbers of mesenchymal stem cells from the washings of bone marrow collection bags: characterization of fresh mesenchymal stem cells

BACKGROUND

Bone marrow (BM) is an excellent source of mesenchymal stem cells (MSC) which can be expanded in vitro for further use. However, large volumes of BM specimens are not routinely available. We hypothesized that the normally discarded BM collection kits might be a convenient source of large numbers of MSC.

METHODS

Marrow specimens were isolated from used Fenwal collection kits. Purified mononuclear cells (MNC) were screened by multiparameter flow cytometry to identify MSC, which were later expanded by in vitro culture. Immunophenotyping and differentiation assays were performed initially and at subculture. Both fresh and frozen BM were tested.

RESULTS

An average of 9.62E+08 MNC were collected. In this, a cell population was identified that was CD44+, CD73+, CD90+ and CD105+, but negative for hematopoietic markers. This population represented on average 0.015% of the total BM MNC fraction, or on average 1 in 6,666 MNC. The population was considered to be MSC based on its immunophenotype profile, suppressive ability in mixed lymphocyte cultures, morphology, and ability to differentiate into bone and fat cells.

CONCLUSIONS

This study demonstrates that large numbers of MSC can be obtained from the normally discarded collection devices following harvest of BM for clinical transplant. This novel method offers potential for obtaining large numbers of MSC for potential therapeutic or investigational purposes following their in vitro expansion.

No oceans on Titan from the absence of a near-infrared specular reflection

With its substantial atmosphere of nitrogen, hydrocarbons and nitriles, Saturn's moon Titan is a unique planetary satellite. Photochemical processing of the gaseous constituents produces an extended haze that obscures the surface. Soon after the Voyager fly-bys in 1980 and 1981 photochemical models led to the conclusion that there should be enough liquid methane/ethane/nitrogen to cover the surface to a depth of several hundred metres. Recent Earth-based radar echoes imply that surface liquid may be present at a significant fraction of the locations sampled. Here we present ground-based observations (at near-infrared wavelengths) and calculations showing that there is no evidence thus far for surface liquid. Combined with the specular signatures from radar observations, we infer mechanisms that produce very flat solid surfaces, involving a substance that was liquid in the past but is not in liquid form at the locations we studied.

Hyaluronic acid of high molecular weight inhibits proliferation and induces cell death in U937 macrophage cells

Hyaluronic acid (HA), a major glycosaminoglycan component of the extracellular matrix, has regulatory influences on cells and cellular activities. To explore the effects of a high concentration (1 mg/mL) of high molecular weight HA (500-730 kD) on U937 macrophage growth dynamics, three factors that influence overall cellular growth, namely proliferation, apoptosis, and cell death, were examined. Cells were cultured with HA and were analyzed by flow cytometry every 24 hours during a 168-hour period for proliferation and the presence of apoptotic and dead cells. These analyses demonstrated that HA inhibits U937 macrophage proliferation in a time-dependent manner. Through the first 72 hours, cells exhibited slowed proliferation. However, no evidence of cell division arrest or reduced cell viability was observed. Thereafter, HA continued to diminish proliferation, but induced apoptosis. This data is consistent with regulatory influences secondary to HA binding to CD44 and/or RHAMM cell surface receptors, both of which were shown to be expressed on U937 macrophages. This study demonstrates that a high concentration of high molecular weight HA greatly inhibits macrophage population growth by the dual actions of impeding cell proliferation and inducing apoptosis.

The inferior parietal lobule is the target of output from the superior colliculus, hippocampus, and cerebellum

The inferior parietal lobule (IPL) is a functionally and anatomically heterogeneous region that is concerned with multiple aspects of sensory processing and sensorimotor integration. Although considerable information is available about the corticocortical connections to the IPL, much less is known about the origin and importance of subcortical inputs to this cortical region. To examine this issue, we used retrograde transneuronal transport of the McIntyre-B strain of herpes simplex virus type 1 (HSV1) to identify the second-order neurons in subcortical nuclei that project to the IPL. Four monkeys (Cebus apella) received injections of HSV1 into three different subregions of the IPL. Injections into a portion of the lateral intraparietal area labeled second-order neurons primarily in the superficial (visual) layers of the superior colliculus. Injections of HSV1 into a portion of area 7a labeled many second-order neurons in the CA1 region of the hippocampus. In contrast, virus injections within a portion of area 7b labeled second-order neurons in posterior regions of the dentate nucleus of the cerebellum. These observations have some important functional implications. The IPL is known to be involved in oculomotor and attentional mechanisms, the establishment of maps of extrapersonal space, and the adaptive recalibration of eye-hand coordination. Our findings suggest that these functions are subserved by distinct subcortical systems from the superior colliculus, hippocampus, and cerebellum. Furthermore, the finding that each system appears to target a separate subregion of the IPL provides an anatomical substrate for understanding the functional heterogeneity of the IPL.

Galileo's First Images of Jupiter and the Galilean Satellites

The first images of Jupiter, Io, Europa, and Ganymede from the Galileo spacecraft reveal new information about Jupiter's Great Red Spot (GRS) and the surfaces of the Galilean satellites. Features similar to clusters of thunderstorms were found in the GRS. Nearby wave structures suggest that the GRS may be a shallow atmospheric feature. Changes in surface color and plume distribution indicate differences in resurfacing processes near hot spots on Io. Patchy emissions were seen while Io was in eclipse by Jupiter. The outer margins of prominent linear markings (triple bands) on Europa are diffuse, suggesting that material has been vented from fractures. Numerous small circular craters indicate localized areas of relatively old surface. Pervasive brittle deformation of an ice layer appears to have formed grooves on Ganymede. Dark terrain unexpectedly shows distinctive albedo variations to the limit of resolution.

Neurons of the anterior mesial cortex related to faciovocal activity in the awake monkey

1. The anterior mesial cortex, including the cingulate region, is thought to be involved in the voluntary control of vocalization. Previous recording studies have demonstrated that anterior mesial neurons discharge before conditioned and spontaneous vocalizations, but questions remain regarding the location and functional properties of these neurons. The present study was performed to provide a more complete description of the location and discharge properties of anterior mesial neurons involved in faciovocal behaviors. 2. Single-unit activity was recorded from neurons in the anterior mesial cortex of monkeys during performance of self-paced vocalizations and jaw openings. Cells were also tested for responsiveness to acoustic stimulation, and attempts were made to elicit vocalization through stimulation of the cortex surrounding related cells. Discharge properties of the cells were statistically analyzed, and correlation analysis was performed between measure of cell discharge and vocalization. 3. A total of 145 neurons were observed to modulate their discharge in association with vocalization or jaw opening. Four general classes of neurons were observed: neurons related only to vocalization, neurons related only to jaw opening, neurons related to both vocalization and jaw opening, and neurons related to other oromotor activities such as lip movements or reinforcement consumption. 4. Vocalization-related cells typically discharged tonically at a low frequency (mean 22 Hz), and many instances of long-lead activity (lead time > 500 ms) were noted. No neurons responded to acoustic stimulation, and electrical stimulation failed to elicit vocalization. Neural activity was not correlated with any measure of vocalization. 5. Neurons related to faciovocal behavior were located in the anterior cingulate sulcus and adjacent cortex of the mesial wall at a level just rostral to the genu of the arcuate sulcus. This region roughly corresponds to the rostral cingulate motor area and is located caudal to the traditionally described cingulate vocalization region. 6. In the present study we demonstrate the existence of an additional region in the medial wall that is involved in a variety of faciovocal behaviors such as vocalization, jaw opening, lip movements, and reinforcement consumption. The neurons do not appear to be strongly coupled to the execution of these acts. These results suggest that the activity of neurons in the anterior mesial cortex may relate to faciovocal behavior in a more global way than the activity of neurons in other motor areas.

Impact debris particles in Jupiter's stratosphere

The aftermath of the impacts of periodic comet Shoemaker-Levy 9 on Jupiter was studied with the Wide Field Planetary Camera 2 on the Hubble Space Telescope. The impact debris particles may owe their dark brown color to organic material rich in sulfur and nitrogen. The total volume of aerosol 1 day after the last impact is equal to the volume of a sphere of radius 0.5 kilometer. In the optically thick core regions, the particle mean radius is between 0.15 and 0.3 micrometer, and the aerosol is spread over many scale heights, from approximately 1 millibar to 200 millibars of pressure or more. Particle coagulation can account for the evolution of particle radius and total optical depth during the month following the impacts.

Spatial Organization and Time Dependence of Jupiter's Tropospheric Temperatures, 1980-1993

The spatial organization and time dependence of Jupiter's temperatures near 250-millibar pressure were measured through a jovian year by imaging thermal emission at 18 micrometers. The temperature field is influenced by seasonal radiative forcing, and its banded organization is closely correlated with the visible cloud field. Evidence was found for a quasi-periodic oscillation of temperatures in the Equatorial Zone, a correlation between tropospheric and stratospheric waves in the North Equatorial Belt, and slowly moving thermal features in the North and South Equatorial Belts. There appears to be no common relation between temporal changes of temperature and changes in the visual albedo of the various axisymmetric bands.

Optical properties of aggregate particles whose outer diameter is comparable to the wavelength

I describe results of numerical calculations of the optical properties (extinction efficiency, single-scattering albedo, phase function, and linear polarization) of aggregate particles whose outer diameter is comparable with the wavelength. Results are presented for two types of particle, one composed of monomers whose radius is small compared with the wavelength and a second containing monomers with larger radii. The shape of the forward-scattered lobe of the phase function is diagnostic of the mean projected area (but differs from that for an equal-area sphere), while the linear polarization, phase function at large scattering angles, and single-scattering albedo depend on the monomer diameter. The wavelength dependence of the extinction efficiency differs markedly from that for equal-area spheres. These results can be used to infer particle properties from remotely sensed data.

Hemorrhage following mandibular osteotomies: a report of 21 cases

Hemorrhage associated with mandibular osteotomies, especially to the extent that it becomes life threatening, is a rare occurrence and its risk is less than that following maxillary orthognathic surgery. Twenty-one cases of significant bleeding following mandibular sagittal split ramus osteotomies, vertical and oblique ramus osteotomies, and genioplasties are presented. Life-threatening hemorrhage associated with mandibular osteotomies is primarily an intraoperative problem and the incidence of major postoperative and recurrent hemorrhage is not as great as following maxillary osteotomies. Suggestions for the avoidance and treatment of these bleeding complications are discussed.

Major vascular complications of orthognathic surgery: false aneurysms and arteriovenous fistulas following orthognathic surgery

False aneurysms and arteriovenous fistulas are rare complications of orthognathic surgery. The vessel most commonly involved with false aneurysms following mandibular surgery is the internal maxillary artery, and this vessel, especially the sphenopalatine branch, may also be involved following maxillary surgery. An unusual factor in the presentation of false aneurysms following Le Fort I osteotomies is an initial episode of epistaxis occurring greater than 2 weeks postoperatively. Arteriovenous fistulas following orthognathic surgery are more apt to involve large vessels, especially the internal carotid artery. Embolization procedures are the treatment of choice for false aneurysms and arteriovenous fistulas in the maxillofacial region following orthognathic surgery.

Thermal Maps of Jupiter: Spatial Organization and Time Dependence of Stratospheric Temperatures, 1980 to 1990

The spatial organization and time dependence of Jupiter's stratospheric temperatures have been measured by observing thermal emission from the 7.8-micrometer CH(4) band. These temperatures, observed through the greater part of a Jovian year, exhibit the influence of seasonal radiative forcing. Distinct bands of high temperature are located at the poles and mid-latitudes, while the equator alternates between warm and cold with a period of approximately 4 years. Substantial longitudinal variability is often observed within the warm mid-latitude bands, and occasionally elsewhere on the planet. This variability includes small, localized structures, as well as large-scale waves with wavelengths longer than approximately 30,000 kilometers. The amplitudes of the waves vary on a time scale of approximately 1 month; structures on a smaller scale may have lifetimes of only days. Waves observed in 1985, 1987, and 1988 propagated with group velocities less than +/-30 meters per second.

Major vascular complications of orthognathic surgery: hemorrhage associated with Le Fort I osteotomies

Major intraoperative or postoperative bleeding associated with Le Fort I osteotomies can be venous and/or arterial in nature. Arterial hemorrhage generally involves the maxillary artery and its terminal branches. Arterial hemorrhage tends to be more persistent and can be recurrent, which makes it more difficult to manage. Postoperative bleeding following Le Fort I osteotomies generally presents as epistaxis and usually occurs initially within the first 2 weeks following surgery. Treatment modalities that have been used to successfully arrest postoperative hemorrhage include anterior and/or posterior nasal packing; packing of the maxillary antrum; reoperating with clipping or electrocoagulation of bleeding vessels, or the use of topical hemostatic agents in the pterygomaxillary region; external carotid artery ligation; and selective embolization of the maxillary artery and its terminal branches.

Aseptic necrosis of the mandible: report of two cases

It appears that clinically significant aseptic necrosis following mandibular osteotomies is a more infrequent occurrence than that following maxillary surgery because only two cases were reported in a questionnaire dealing with major vascular complications following orthognathic surgery. Significant necrosis is unlikely to occur if a surgeon follows the basic principle of stripping the minimal amount of mucoperiosteum and muscle attachment from the osteotomized segments commensurate with the successful completion of the osteotomies.

Photometry from Voyager 2: Initial Results from the Neptunian Atmosphere, Satellites, and Rings

The Voyager photopolarimeter successfully accomplished its objectives for the Neptune encounter, performing measurements on the planet, several of its satellites, and its ring system. A photometric map of Neptune at 0.26 micrometer (microm) shows the planet to be bland, with no obvious contrast features. No polar haze was observed. At 0.75 microm, contrast features are observed, with the Great Dark Spot appearing as a low-albedo region and the bright companion as being substantially brighter than its surroundings, implying it to be at a higher altitude than the Great Dark Spot. Triton's linear phase coefficients of 0.011 magnitudes per degree at 0.26 microm and 0.013 magnitudes per degree at 0.75 microm are consistent with a solid-surface object possessing high reflectivity. Preliminary geometric albedos for Triton, Nereid, and 1989N2 were obtained at 0.26 and 0.75 microm. Triton's rotational phase curve shows evidence of two major compositional units on its surface. A single stellar occultation of the Neptune ring system elucidated an internal structure in 1989N1R, in the approximately 50-kilometer region of modest optical depth. 1989N2R may have been detected. The deficiency of material in the Neptune ring system, when compared to Uranus', may imply the lack of a "recent" moon-shattering event.

Factors influencing the stability of the sagittal split osteotomy for mandibular advancement

Relapse continues to be a potential problem with use of the sagittal split osteotomy to advance the mandible. In an effort to isolate predictive factors, the records of 235 patients were analyzed to determine the pretreatment facial morphology, the amount of advancement, the amount of relapse, and the duration of relapse. No relationship was found between any of the measures of facial morphology and relapse. However, the amount of advancement, the amount of relapse, and the duration of relapse all were found to be strongly related. It was found that all patients shared a similar facial morphology, and thus no influence of facial form on relapse would be expected from this group. The relationships between advancement and relapse could be attributed to neuromuscular adaptation, which would be more prolonged and more extensive in instances of greater advancement, and thus give rise to relapse of greater extent and duration. It is therefore suggested that mandibular advancements of greater than 10 mm be fixed more rigidly and for a greater length of time than those of lesser magnitude.

Ptosis of the chin and lip incompetence: consequences of lost mentalis muscle support

Ptosis of the chin and lip incompetence are worrisome complications of surgery in the mandibular symphyseal region. This article relates the normal anatomy and physiology of the muscles in this region to these complications. It suggests a sequence of surgical planning that can prevent them and also offers ways of dealing with the problems should they occur.

Jaw deformity caused by juvenile rheumatoid arthritis and its correction

An underdeveloped mandible and resulting micrognathia and malocclusion may occur in some children with juvenile rheumatoid arthritis. Combined orthodontic and surgical procedures can now greatly improve esthetics and function in such children. We describe corrective treatment and followup of 7 patients.

Photometry from Voyager 2: Initial Results from the Uranian Atmosphere, Satellites, and Rings

The Voyager 2 photopolarimeter successfully completed the Uranus encounter, acquiring new data on the planet's atmosphere, its principal satellites, and its ring system. Spatially resolved photometry of the atmosphere at 0.27 micrometer shows no enhancement in absorption toward the pole, unlike the case for Jupiter and Saturn. Stellar occultation measurements indicate the temperature at the 1-millibar level over the north pole is near 90 kelvins. The geometric albedos of the five large satellites of Uranus were measured at 0.27 and 0.75 micrometer and indicate the presence of low albedo, spetrally flat absorbing material. Titania seems to have a fluffy surface, as indicated by its phase curve. The nine ground-based rings were detected, and their internal structure, optical depths, and positions were determined. The sharp edges of the in ring made it possible to measure its edge thickness (less than 150 meters) and particle sizes (less than 30 meters); little or no dust was detcted. New narrow rings and partial rings (arcs) were measured, and the narrow component of the eta ring was found to be discontinuous.

Personality characteristics as predictors and sequelae of surgical and conventional orthodontics

The aims of this study were to determine the effects of surgical and conventional orthodontics on patients' body image and self-esteem and the association between personality characteristics and postoperative reports of pain, paresthesia, swelling, and satisfaction among 90 patients who underwent surgical orthodontics. Patients who underwent surgery completed questionnaires before their operations and up to 6 months after surgery. Self-esteem and body image were compared longitudinally between these patients and 33 persons who were undergoing orthodontic treatment only and 33 persons who had decided against treatment. Results suggest that patients' self-esteem, body image, and degree of extroversion are unrelated to postsurgical satisfaction and discomfort. Neuroticism was correlated with satisfaction, so that patients who scored in the higher range on a scale of neuroticism were less satisfied immediately after surgery and at removal of fixation wires. Neurotic patients also were more likely to complain of pain and swelling 6 months after surgery. Surgical patients held a more negative facial image and were more introverted than those in the other two groups but were similar in other personality traits before surgery. Both surgical and orthodontic patients improved significantly in body image over time, with the greatest increase among the former. Similar shifts in self-esteem occurred for the three groups, suggesting that surgery per se may not be the major determinant of longitudinal changes in self-esteem. Notably, the positive effect of surgery and orthodontic treatment on body image is an important motive for many persons seeking treatment. Results of this study provide important insights into how to prepare and counsel patients undergoing orthodontic treatment with and without surgery.

Mandibular advancement surgery. A study of the lower border wiring technique for osteosynthesis

A study was undertaken to evaluate the effectiveness of osteosynthesis achieved by a lower border wire technique. Fifty patients who underwent mandibular advancement surgery were examined cephalometrically during 6 weeks of maxillomandibular fixation. A detailed analysis was made of spatial changes in the proximal and distal segments following bilateral sagittal-split osteotomies.

The emotional impact of orthognathic surgery and conventional orthodontics

Previous research by the authors has pointed to depressive reactions among orthognathic surgery patients during the fixation-removal stage and up to 9 months later. However, less is known about emotional shifts among persons who choose to undergo conventional orthodontic treatment after considering surgical orthodontics. In the current study, a standard measure of mood states was applied to 90 surgical patients and 66 who had considered surgery but decided against it. Of these, 33 were undergoing orthodontic treatment and 33 were having no treatment. The mood scale and measures of personality were first applied before surgery and then during orthodontic treatment, just after surgery, at fixation removal, and 6 months after surgery. Nonsurgical respondents completed questionnaires at the same time as their matched surgical respondents. Scores on tension and fatigue increased significantly among surgical patients from before surgery to immediately after surgery and dropped to presurgical levels when fixation was removed. Anger-hostility increased at fixation removal but declined within 5 months. Postsurgical discomfort, pain, and paresthesia, and interpersonal and oral function problems were correlated with postsurgery emotional state. On the later questionnaires, which corresponded to the later periods of orthodontic treatment, patients who had opted for conventional orthodontic treatment reported that they experienced greater depression, anger, and tension. These patients may be particularly vulnerable to emotional problems because their orthodontic treatment may be more complex and of longer duration than that of the typical orthodontic patient. These results point to the importance of continued psychological support for both orthodontic and surgical patients throughout their course of treatment.

Condylar position following mandibular advancement: its relationship to relapse

Forty-one patients who elected to receive a bilateral sagittal osteotomy to advance the mandible were examined clinically and radiographically to assess condylar position preoperatively and at three specific times postoperatively. Parameters designed to measure changes in condylar and distal fragment position were located on tracings and digitized for statistical analysis. Changes in distal fragment position included advancement and clockwise rotation during the surgical interval and significant posterior relapse with continued clockwise rotation during the period of maxillomandibular fixation. A small amount of counterclockwise rotation associated with interocclusal splint removal was seen following fixation release. No significant condylar movement was seen during the surgical interval. During the period of maxillomandibular fixation, both condyles exhibited a significant superior movement, and the left condyle also moved posteriorly. No changes in condylar position were noted following release of fixation. The clinical significance of these condylar movements is not clear. Despite minimal changes, 18 patients, six of whom had had no preoperative symptoms and one of whom had exhibited reciprocal clicking, complained of temporomandibular joint pain or noise postoperatively. This suggests that maintenance of condylar position during surgery may not prevent temporomandibular joint dysfunction. In addition, the observed 37% relapse in surgical advancement in the absence of significant condylar distraction implies the interaction of other factors in the relapse process.

Psychologic changes in orthognathic surgery patients: a 24-month follow up

This report describes the final, two-year follow up in a longitudinal study of 74 patients who underwent orthognathic surgery for developmental deformities. Data for all six measurement periods were available for 46 patients. Complaints of functional problems decreased significantly from before surgery to 24 months after, although 49% of the patients continued to report lip paresthesia. The incidence of postsurgical problems had no effect on the satisfaction expressed with surgical outcomes, which remained high throughout the postoperative course. Self-esteem appeared to rise in anticipation of surgery, only to decline significantly at nine months after surgery, to rise again by 24 months (but not as high as before surgery). In some components, self-esteem remained significantly lower after surgery than before. Body image also showed a decline at nine months, although overall body image and profile image 20-26 months after surgery were significantly more positive than before surgery. These results point to the importance of continued contact with orthognathic surgery patients by surgeons and orthodontists for at least two years after surgery, particular attention being paid to the intermediate stages (six to 12 months) after surgery. This period of psychologic upheaval appears to be related to the patient's desire to complete postsurgical orthodontics.

Management of postoperative hemorrhage following the Le Fort I maxillary osteotomy

The assessment and management of patients with postoperative hemorrhage following Le Fort I osteotomies is discussed. The results of a questionnaire to investigate this complication, as well as the authors' protocol for dealing with this problem, are presented. Three illustrative case histories are also presented.

Orthodontics and orthognathic surgery: adjuncts to restorative and periodontal therapy

Orthodontic and orthognathic surgical procedures are important adjuncts to the provision of optimum restorative and periodontal care. Dentoalveolar and skeletal abnormalities of either developmental or acquired origin can be corrected primarily, thus eliminating the necessity for compromise in prosthetic design. Dental relationships that are contributory to irreversible periodontal deterioration can be normalized to facilitate stabilization of the periodontal condition and to increase the longevity of the natural dentition. Maxillofacial surgical treatment is technically complex but is more conservative than many traditionally accepted treatment procedures. It is based on the rationale of conservation of natural structures rather than their radical ablation or their sacrifice to uncontrollable progressive disease processes. Patient participation to establishment of treatment objectives and extensive patient education are essential ingredients in such treatment. Interdisciplinary communication and coordination contribute to a mutual appreciation of treatment possibilities and limitations. Thus, orthodontic and orthognathic surgical options should be considered in planning the solution to a wide variety of periodontal and restorative treatment problems.

Recreational and social activities of orthognathic surgery patients

The present study examined changes in recreational and social activities after orthognathic surgery. Because this is often an expectation of patients seeking surgery, it was hypothesized that activity levels would increase gradually after surgery, particularly for patients who become more extroverted and for unmarried patients. Information on the frequencies of recreational and social activities, and the persons with whom these activities were performed, were obtained from 53 patients in a self-administered questionnaire administered at least 2 days before surgery and again 3 weeks, 4 months, and 9 months after surgery. In addition, patients were assessed on introversion-extroversion before and after surgery. The results indicated that (1) for both married and single patients, recreational and social activities dropped immediately after surgery and gradually increased to a level similar to that prior to surgery at nine months after surgery; (2) contrary to expectations, the single patients over age 15 did not increase their recreational and social activities with friends of the opposite sex after surgery; and (3) the degree of change in introversion-extroversion after surgery was not associated with the degree of change in recreational and social activities performed with others. Implications for postsurgical adjustment of orthognathic patients and recommendations for future research are discussed.

The psychological impact of orthognathic surgery: a 9-month follow-up

In an attempt to determine the impact of surgical orthodontics on patients' personality and perceptions of oral function, fifty-five patients were examined longitudinally. Patients completed five questionnaires during the course of treatment, from 1 month before to 9 months after surgery. Orthodontic appliances were still being worn by 56.1 percent at the 9-month assessment. Satisfaction with surgery, self-esteem, and body image were high throughout the postsurgical stage but showed significant changes. Satisfaction peaked at 4 months but declined at 9 months postsurgery, as did self-esteem and facial body image. Most of this decline was attributable to patients being still under orthodontic treatment, but those with continuing problems of pain, paresthesia, and oral dysfunction were not more likely to report psychological dissatisfaction. Results are examined from the perspectives of integration of body image and patient expectations from orthognathic surgery.

Surgical correction of vertical maxillary excess: a re-evaluation

Correction of vertical maxillary excess by Le Fort I osteotomy has become a widely accepted practice. Although the downfracture method is used almost exclusively in most major centres, the total maxillary alveolar osteotomy still has its advocates. Two patients surgically treated by total maxillary alveolar osteotomy and presented in this journal are re-evaluated with respect to the long-term stability of maxillary intrusion. Literature pertaining to the stability of the maxilla following intrusion by Le Fort I osteotomy and after various combinations of anterior and posterior maxillary ostectomy is reviewed. The advantages of the downfracture method are discussed. An alternative method of achieving the desired degree of intrusion is presented, which ensures more intimate bone contact.

Predicting psychologic responses to orthognathic surgery

A longitudinal study was conducted of the psychologic characteristics of 74 persons undergoing orthognathic surgery. The effects of neuroticism, locus of control, and expectations upon postsurgical outcomes were examined. The majority of patients scored in the normal range of most personality variables. The findings suggest a generally intact ego and accurate self-concept among orthognathic surgery patients. Expectations of pain and parasthesia were the best predictors of postsurgical outcomes, while neuroticism and locus of control scores predicted some outcomes in the early postoperative stages. The results indicate the importance of preparing orthognathic surgery patients against unrealistic expectations before surgery is undertaken, and of counseling certain patients during the early postoperative period.

Photopolarimetry from Voyager 2; Preliminary Results on Saturn, Titan, and the Rings

The Voyager 2 photopolarimeter was reprogrammed prior to the August 1981 Saturn encounter to perform orthogonal-polarization, two-color measurements on Saturn, Titan, and the rings. Saturn's atmosphere has ultraviolet limb brightening in the mid-latitudes and pronounced polar darkening north of 65 degrees N. Titan's opaque atmosphere shows strong positive polarization at all phase angles (2.7 degrees to 154 degrees ), and no single-size spherical particle model appears to fit the data. A single radial stellar occultation of the darkened, shadowed rings indicated a ring thickness of less than 200 meters at several locations and clear evidence for density waves caused by satellite resonances. Multiple, very narrow strands of material were found in the Encke division and within the brightest single strand of the F ring.

Diagnosis and treatment planning: a coordinated effort between oral and maxillofacial surgery and orthodontics

Recent years have seen broad technical advancements in the field of orthognathic surgery. Recognition that conventional orthodontic-orthopedic treatment is ineffective in resolving facial-skeletal deformities and associated malocclusions has led to the development of cooperative therapeutic efforts. Joint diagnosis and treatment planning and analysis of longitudinal treatment responses based on traditional orthodontic principles have contributed to continuing advancement of knowledge and improvement in standards of care. A team approach to the management of patients requires the sharing of knowledge, skills, and responsibility. By combining these with a high level of education of patients, cosmetic and functional changes of lasting benefit can be achieved.

Surgical mandibular advancement: a cephalometric analysis of treatment response

Fifty-two cases of surgical advancement of the mandible were evaluated by retrospective cephalometric and computer analysis for longitudinal skeletal and dental changes an average of 3 1/2 years after surgery. Postsurgical treatment response appeared to be a multifactorial biologic phenomenon with considerable individual variability. Results showed generally good stability after mandibular advancement, with a minimal to moderate tendency toward skeletal relapse during intermaxillary fixation. Positional change of the proximal segment was the most important parameter in determining stability or relapse of the advanced mandible. Anteroinferior displacement of the condyle and increased posterior facial height were found to be important factors in the skeletal relapse observed during the period of intermaxillary fixation. The magnitude of mandibular advancement was a reliable surgical predictor of postsurgical relapse. Preoperative mandibular plane angle, postfixation intersegment instability, and patient's age cannot be isolated as being solely responsible for specific postsurgical changes.

Spontaneous pneumomediastinum associated with orthognathic surgery. A case report

Numerous articles identifying pneumomediastinum as an immediate complication of dental and oral surgical procedures have been published. A patient who developed a spontaneous pneumomediastinum as a delayed complication, apparently not directly related to the surgical procedure, is presented in this report.