Background Nasolabial dermal filler (DF) injections are one of the most popular cosmetic procedures performed worldwide. DF injections at the nasolabial fold have been associated with nasal necrosis due to inadvertent intravascular injection of the adjacent facial artery (FA). Current DF injection protocols are devoid of imaging the anatomical site, and the use of ultrasound (US) for imaging the FA is very limited in literature. The purpose of this study is to determine the feasibility of utilizing US to identify and measure the FA at different bony landmarks near and within the nasolabial region. Methods Part I Cadaveric dissections (n=18; 10 female, 8 male) will be completed to explore the course of the FA from the external carotid artery to the terminal branches supplying facial structures. Part II A bilateral US of the FA using 13–6 MHz, 38 mm linear array US transducer was performed on consenting adults (n=16; 9 female, 7 male) from the Department of Anatomy and Cell Biology at Western University. The following bony landmarks were identified and used for US measurements, taken in real time: anterior‐inferior angle of the mandible, mandibular teeth, maxillary teeth, maxillary ridge. Measurements of FA diameter, artery distance to skin, and artery distance to bone were obtained at each landmark using digital image distance measurements on the Sonosite M‐Turbo P08189‐88R US machine. Results Part I Preliminary results (n=8; 4 female, 4 male) show FA variability between cadaveric specimens, as well as left/right FA variability within cadaveric specimens themselves. Part II Preliminary results of the average FA distance to the skin measured at 0.438 cm ± 0.126 for the left FA and 0.459 cm ± 0.205 for the right FA. A significant difference (P< 0.05) was noted for FA distance to the skin between the left mandibular teeth (0.481 cm ± 0.107) and left maxillary ridge (0.343 cm ± 0.097). Conclusions These findings highlight the importance of understanding the anatomy of the FA within the nasolabial fold, and the need to carefully personalize the placement of DF injections, due to the anatomical variability identified in both the cadaveric and ultrasound portions of the study. Furthermore, since it is feasible to identify and measure the FA using the selected US transducer, the future direction of this study will be to examine the application of US to guide DF injections. This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .

The morphological characteristics of the Mandibular Fossa, the temporal component of the temporomandibular joint (TMJ), have been described using methods with several limitations. For instance, the inclination of the Mandibular Fossa (MF) towards its anterior eminence has been measured using lateral cephalometric radio-graphs. This approach not only compromises the real anatomy of the MF by tilting the patient's head to avoid superimposed left and right images. But also classifies a complex three-dimensional shape using a single two-dimensional radio-graphic projection. Furthermore, the overall thickness distribution of articular cartilage coating the MF is unknown. The aim of this study is to generate the first objective method to describe the topology of the MF and its overall articular cartilage distribution. Six bisected heads (4 males and 2 females; age 73: ± 11.76 years) were dissected in order to expose the left and right mandibular fossae and the occipital condyles. The articular cartilage of the MF was preserved while half of the condylar cartilage was removed. The subjects were then stained 48 hours prior being micro CT scanned. The RAW data was reconstructed and the occipital condyle used for the calculation of the threshold values for the segmentation of bone and cartilage. The distance between bone/cartilage and the Frankfort Horizontal plane was calculated. The data generated two topographic images used to locate the deepest point of the MF, the highest point of the anterior eminence and any substantial change in the morphology. Finally, an image of the overall distribution of cartilage thickness was obtained by subtracting the values of bone out of the topographic image of cartilage. The analysis of bone and cartilage showed that the highest point, determined as the point in the corresponding mesh located farther away from the Frankfort plane, is located 100% (n=12) of the times in the anterolateral quadrant of the MF. In contrast, the lowest point is located 100% (n=12) of the times in the posteromedial quadrant. The contour analysis on the bone showed that the anterior eminence has an antero-posterior groove roughly located at the level of the middle line in 83.34 % of the specimens (n=10). The thickness of the cartilage showed two areas of increased value. One lined parallel to the junction between the fossa and the anterior eminence the other above the before mentioned bony groove. The fact that the internal topography of the MF presents a cross shaped structure may explain the causes of instability among total joint replacement patients and play an important role when studying condyle rotation and anterior translation. The areas of thickening correlate with previous research that has identified the areas where functional bio-mechanical loads are the strongest. Our results demonstrate the biological response of the articular cartilage to these compressing forces. Both findings can improve the way total joint prosthesis are being manufactured and contribute with the future of TMJ bio-engineering systems. Support or Funding Information Senescyt (Secretaria Nacional de Educación Superior Ciencia, Tecnología e Innovación) 3D Representation of the isosurface of bone (Light Brown) and the articular cartilage (Light Blue) The thickness of the cartilage can be better represented using topographic images. Topographic analysis of the bone structure of the (GF) The colours indicate the difference between distance of the Frankfort plane and the surface of the articular surface of the bone. The deepest point is opposite to the highest elevation. Also there is a grove in the middle of the joint where the Mandibular Condyle moves anteriorly. Difference between bone and articular cartilage. The color map indicates the measurements in a scale from 0 to 256. The resolution of the image is 154 μm. 3D Representation of the isosurface of bone (Light Brown) and the articular cartilage (Light Blue) The thickness of the cartilage can be better represented using topographic images. Topographic analysis of the bone structure of the (GF) The colours indicate the difference between distance of the Frankfort plane and the surface of the articular surface of the bone. The deepest point is opposite to the highest elevation. Also there is a grove in the middle of the joint where the Mandibular Condyle moves anteriorly. Difference between bone and articular cartilage. The color map indicates the measurements in a scale from 0 to 256. The resolution of the image is 154 μm.

The greater palatine nerve and the greater palatine canal are common sites for maxillary anesthesia during dental and maxillofacial procedures. The greater palatine nerve is thought to course as a single trunk through the greater palatine canal, branching after its exit from the greater palatine foramen. We describe intra-canalicular branching variations of the greater palatine nerve found in 8 of 20 embalmed dissection specimens. Such variation is previously unreported in the literature. We characterize the variations in branching pattern and discuss the possible implications for clinical practice.

Gap junctions consist of clusters of intercellular channels composed of connexins that connect adjacent cells and allow the exchange of small molecules. While the 21 member multi-gene family of connexins are ubiquitously found in humans, only Cx39, Cx40, Cx43 and Cx45 have been documented in developing myoblasts and injured adult skeletal muscle while healthy adult skeletal muscle is devoid of connexins. The use of gap junctional blockers and cultured myoblast cell lines have suggested that these connexins play a critical role in myotube formation and muscle regeneration. More recent genetically-modified mouse models where Cx43 function is greatly compromized or ablated have further supported a role for Cx43 in regulating skeletal muscle development. In the last decade, we have become aware of a cohort of patients that have a development disorder known as oculodentodigital dysplasia (ODDD). These patients harbor either gain or loss of Cx43 function gene mutations that result in many organ anomalies raising questions as to whether they suffer from defects in skeletal muscle formation or regeneration upon injury. Interesting, some ODDD patients report muscle weakness and loss of limb control but it is not clear if this is neurogenic or myogenic in origin. This review will focus on the role connexins play in muscle development and repair and discuss the impact of Cx43 mutants on muscle function.

The mandibular interforaminal region is considered a safe zone for cortical bone graft harvesting. Incidence of sensory disturbance of the anterior dentition is reported following harvest at the mandibular symphysis. Anatomical understanding of the incisive nerve within the bony mandible is required to prevent nerve injury. Our study of the anatomy of the incisive nerve, its variation, and position within the mandible will provide a comprehensive map for surgeons. Thirty‐eight cadaveric mandibles will be dissected to reveal the incisive nerve within the mandibular symphysis. The nerve formation will be categorized as: Type A (trunk with branches to anterior teeth), B (a disorganized plexus), or C (nearby nerve contribution). Categorical prevalence will be compared in dentate and edentulous mandibles. A subset of mandibles will be sagittally sectioned between the mental foramina to show the incisive nerve relative to the inferior border of the mandible. Preliminary results of 11 dissected dentate mandibles reveal a prevalence of the ‘Type A’ formation between the mental foramina (8/11). Two dentate mandibles have shown ‘Type B’ formation. Dissected edentulous mandibles reveal a prevalence of ‘Type A’ formation (3/3). Elucidation of anatomical formation, variation, and position of the incisive nerve will help decrease the morbidity of incisive nerve damage and provide a better long‐term outcome for patients.

BACKGROUND:Greater palatine nerve (GPN) block is commonly performed for maxillary and palatal anesthesia by using bony landmarks. Ultrasound (US) can be used to consistently identify greater palatine foramen (GPF) as a defect in the bony palate enabling US-guided injections near the foramen. METHODS:We scanned and injected 16 undissected well-embalmed hemisectioned cadaveric heads after excluding major anatomical malformations. A linear high-frequency hockey stick probe (7-13 MHz) positioned in long axis to the hard palate visualized GPF as a discontinuity in the hard palate. US-guided injections of 0.1 mL India ink were made in an oblique plane. Specimens were dissected immediately after injection, and dye distribution was noted. The success rate of identification of GPF, number of attempts, and number of successful injections were recorded. The technique was evaluated clinically in 7 patients undergoing dental procedures. Five patients had US-guided injections, and 2 patients received US-assisted greater palatine canal blocks. RESULTS:GPF was successfully identified in 16 hemisectioned heads (n = 16). In 7 of 16 hemisectioned cadaveric specimens (n = 7/16), needle pass was seen on the US and traces of India ink were found within the greater palatine canal and pterygopalatine fossa. In the remaining heads (n = 9/16), the dye was observed in the mucosal tissue of the hard palate anterior to the GPF or in the soft palate. Clinical evaluation reconfirmed successful identification of GPF by US in 6 of 7 patients (n = 6/7). US-guided injections were successful in 6 of the 8 attempted blocks (n = 6/8) with median number (range) of attempts being 2 (1-4). US-assisted injections were successful in 2 patients (n = 2/2). CONCLUSIONS:US has the potential to successfully locate and characterize GPF in normal and edentulous maxilla. US-guided GPN blocks can be technically challenging. The clinical applicability of US guidance or assistance for GPN block needs further evaluation in a larger sample of patients.

Anterior iliac crest bone grafting (AICBG) remains the gold standard for reconstructive procedures in orthopedic and oral‐maxillofacial surgeries. It has been estimated that 10% of patients undergoing AICBG are at risk of injury to their lateral femoral cutaneous nerve (LFCN). Injury to this nerve can result in numbness, burning, itching or pain sensations over the lateral aspect of the thigh, known as meralgia paresthetica. The course of the LFCN within the greater pelvis cannot be seen with imaging technologies. The objective of this study is to elucidate the 3D course and variability of the LFCN as it emerges from the psoas major muscle to the anterior superior iliac spine (ASIS). Using 25 embalmed cadavers, the length and depth of the LFCN is measured from the ASIS to 7 cm posterior to the ASIS at 1 cm intervals. Preliminary results (n=10 sides) show these measurements are highly variable between cadavers and that there are three ways the nerve courses: convex, concave or straight course. The first three dimensional danger‐zone of the LFCN relative to the iliac crest will be established and incorporated onto a 3D illustration of the pelvic bone using Amira software. A predictive model will be determined to approximate the location of the LFCN with respect to age, sex, height, bone width, and ASIS‐ASIS distance. A better understanding of the course of the LFCN is important to minimize graft site morbidity.

BackgroundA greater palatine nerve (GPN) block is required for many dental procedures. Localization of the nerve currently relies on a blind, surface landmark approach, which often requires multiple needle pricks and a large amount of local anesthetic. Ultrasound (US) is a safe, non‐invasive modality and bone appears as a white line on an US. Any disruption in this line may indicate a discontinuity in bone such as a foramen.HypothesisAn US‐guided approach can be used to locate the greater palatine foramen (GPF) and isolate the GPN on the hard palate.Material & MethodsIn this study, 16 cadaveric hard palates were scanned by a linear probe and an US‐guided injection of India ink was administered into the GPF of all the specimens.ResultThe hard palate was visible as a white continuous line and an interruption in this line near the maxillary molar teeth was recognized as the GPF in all of the 16 specimens. In 9 out of 16 specimens, traces of India ink were found in the greater palatine canal.ConclusionUS can be effectively used to visualize both the GPF and GPN in palates with and without molar teeth and an ultrasound guided GPN block could be considered as an adjunct to dental clinics. These findings may warrant follow‐up testing on patients in the dental clinic. The author is supported by OGS funds.Grant Funding Source: Departmental

The temporomandibular joint's (TMJ) articular disc facilitates normal function in the healthy joint. Temporomandibular disorders (TMDs) are associated with disc derangement or damage resulting in joint dysfunction. TMD can progress to an end‐stage where surgical removal of condyle and disc are performed. No adequate prosthetic replacement exists for the disc. A dimensional model for the disc is yet to be provided. Our objective is to assess the dimensions of the articular disc providing a structural scaffold for tissue engineering of replacement constructs. Discs were dissected bilaterally from 12 cadavers (56–100yrs). Linear surface dimensions of the discs were measured using digital calipers to assess absolute and regional anteroposterior width (APW) and mediolateral length (MLL). Regional measurements were taken perpendicularly at relative ratios of the absolute dimensions (50% central; 20% from borders). All measurements (mm) were repeated twice by 2 observers to assess reliability. Mean absolute APW (15.31±1.08) and MLL (24.71±2.29) were calculated from 9 specimens along with mean values for 6 regional surface measurements and 9 regional depth measurements per disc. Within the limits of this study it is possible to provide reliable dimensions for use in creating a structural scaffold of the TMJ articular disc.Grant Funding Source: Departmental Funding

Muscle architecture, the arrangement of fibre bundles within the muscle volume, has important functional implications. Previous studies of infraspinatus (IS) muscle architecture have focused on dissection and photography of the superficial muscle layers rather than a volumetric analysis. The aim of this study was to develop a methodology to quantify the architectural parameters of the fibre bundles throughout the volume of IS. As a prototype, one formalin‐embalmed cadaveric specimen was used. The IS was exposed and each fibre bundle was meticulously dissected and digitized from end to end. The digitized data was imported and a 3D model of the fibre bundle architecture, as in situ, was constructed in Autodesk® Maya®2012. Architectural parameters including fibre bundle length (FBL), pennation angle (PA), and physiological cross sectional area (PCSA) were computed. Based on the architectural parameters, muscular partitioning was determined. This technique successfully captured IS architecture throughout its volume. The IS was found to consist of 2 architecturally distinct regions, superior and inferior. The average measures for the superior and inferior regions were respectively: FBL 115.3mm; PA 22.2°; PCSA 180.3mm2 and FBL 84.9 mm; PA 15.9°; PCSA 550.5 mm2. The results suggest that there is muscular partitioning of the IS. This methodology will form the basis of a continuing study to understand detailed IS architecture at the fibre bundle level.

Neuromuscular partitioning is important in defining functional differences within a muscle volume. It has been shown that individual neuromuscular partitions may be differentially affected in pathology. Neuromuscular partitions are defined by independent innervation and architectural differences. Infraspinatus (IS) is a functionally important rotator cuff muscle where neuromuscular partitioning has not been well studied. The purpose is to investigate the intramuscular innervation patterns of IS. In this pilot study, 5 formalin‐embalmed cadaveric have been dissected, digitized, and modeled to date. The suprascapular nerve (SSN) was digitized sequentially in short segments and the data was modeled using Autodesk® Maya®2012. The models were used to document the intramuscular innervation patterns/neuromuscular partitions. The SSN enters IS at the spinoglenoid notch as 1–3 nerves. In three specimens, one nerve entered the IS belly and divided into 3 main branches: (1) a superior branch (br) to superior part of the muscle belly; (2) a lateral br to upper inferior belly; (3) middle br to middle and lower inferior bellies. When SSN enters as 2–3 branches, a separate lateral and/or superior branch enter their respective regions. These results provide a detailed mapping of the intramuscular innervation of IS, providing evidence of neuromuscular partitioning within the IS muscle belly.

Numerous reports have documented the beneficial effects of dietary docosahexaenoic acid (DHA) on beta-amyloid production and Alzheimer's disease (AD). However, none of these studies have examined and compared DHA, in combination with other dietary nutrients, for its effects on plaque pathogenesis. Potential interactions of DHA with other dietary nutrients and fatty acids are conventionally ignored. Here we investigated DHA with two dietary regimes; peptamen (pep+DHA) and low fat diet (low fat+DHA). Peptamen base liquid diet is a standard sole-source nutrition for patients with gastrointestinal dysfunction. Here we demonstrate that a robust AD transgenic mouse model shows an increased tendency to produce beta-amyloid peptides and amyloid plaques when fed a pep+DHA diet. The increase in beta-amyloid peptides was due to an elevated trend in the levels of beta-secretase amyloid precursor protein (APP) cleaving enzyme (BACE), the proteolytic C-terminal fragment beta of APP and reduced levels of insulin degrading enzyme that endoproteolyse beta-amyloid. On the contrary, TgCRND8 mice on low fat+DHA diet (based on an approximately 18% reduction of fat intake) ameliorate the production of abeta peptides and consequently amyloid plaques. Our work not only demonstrates that DHA when taken with peptamen may have a tendency to confer a detrimental affect on the amyloid plaque build up but also reinforces the importance of studying composite lipids or nutrients rather than single lipids or nutrients for their effects on pathways important to plaque development.

The clinical application of stem cell therapy for myocardial infarction will require the development of methods to monitor treatment and pre-clinical assessment in a large animal model, to determine its effectiveness and the optimum cell population, route of delivery, timing, and flow milieu.

Myogenesis is regulated by the MyoD class of myogenic regulatory factors (MRFs). These basic helix-loop-helix transcription factors dimerize with E proteins to bind conserved E-box sequences in the promoter regions of muscle-specific genes. Perhaps due to their expression in a wide array of tissues, the specific interactions of E proteins with different MRFs have been largely ignored. Likewise, the expression of E proteins in muscle tissue remains mostly uncharacterized. We investigated the expression of the E proteins HEB, E12, and E47 in rat L6 myoblasts, which express only embryonic and fast (2X) myosin heavy chains (MyHCs) in vitro, C2C12 myosatellite cells, and a number of muscle tissues, to determine whether myosin heavy chain diversity is mirrored by diversity in E protein or MRF expression. Although L6 and C2C12 myotubes demonstrate strong expression of embryonic and 2X (fast) MyHCs, immunofluorescence demonstrated the additional expression of type 1 (slow), 2A, and 2B MyHCs in the C2C12 cell line. Immunofluorescence and western blot analyses show that HEB was expressed in differentiating L6 myoblasts, C2C12 cells, and neonatal rat primary myotubes. In contrast, E12 and E47 expression was not detected in either cell line or in any adult muscle tissue examined. These data strongly implicate HEB in the development of skeletal muscle. However, because HEB is expressed in L6 myoblasts, C2C12 myosatellite cells, and neonatal hindlimb muscles, it is unlikely to be involved in a fiber type-specific manner, and may have a more general role in differentiation of myotubes.

Microscopy Research and TechniqueVolume 50, Issue 6 p. 425-429 Topical Paper Phylogenetic diversity of myosin expression in muscle Peter Merrifield, Corresponding Author Peter Merrifield [email protected] Department of Anatomy and Cell Biology, The University of Western Ontario, London, Ontario, Canada N6A 5C1Department of Anatomy and Cell Biology, The University of Western Ontario, London, Ontario, Canada N6A 5C1Search for more papers by this authorBurr G. Atkinson, Burr G. Atkinson Department of Zoology, The University of Western Ontario, London, Ontario, Canada N6A 5C1Search for more papers by this author Peter Merrifield, Corresponding Author Peter Merrifield [email protected] Department of Anatomy and Cell Biology, The University of Western Ontario, London, Ontario, Canada N6A 5C1Department of Anatomy and Cell Biology, The University of Western Ontario, London, Ontario, Canada N6A 5C1Search for more papers by this authorBurr G. Atkinson, Burr G. Atkinson Department of Zoology, The University of Western Ontario, London, Ontario, Canada N6A 5C1Search for more papers by this author First published: 15 September 2000 https://doi.org/10.1002/1097-0029(20000915)50:6<425::AID-JEMT1>3.0.CO;2-FCitations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume50, Issue6Special Issue: The Biology of Myosin15 September 2000Pages 425-429 RelatedInformation

In tadpoles of the North American bullfrog, Rana catesbeiana, spontaneous and thyroid hormone (T3)-induced metamorphosis is characterized by regression of the tail, which is preceded by a decrease in total protein synthesis in tail tissues. We have demonstrated that thyroid hormone treatment of a tadpole does not affect the synthesis of all proteins equally in the tadpole tail muscle. For example, the synthesis of myosin heavy chains (MHCs) is depressed within 1 day and decreases to 45% of control values after 5 days of T3 treatment, whereas the decreased synthesis of soluble muscle proteins is transient and returns to above control levels by day 5. To determine whether the hormone-induced decrease in MHC synthesis is the result of changes in the transcription or translation of MHC mRNAs, we isolated cDNAs complementary to five different MHC mRNAs from a tail muscle cDNA library and used them to examine the levels of each MHC mRNA in the tail muscle of T3-treated tadpoles. mRNAs that recognize the cDNAs for these five different MHCs are all expressed in the tadpole tail and limb muscles, as well as in the adult leg muscles. MHC mRNAs unique to tadpole tail were not detected. Interestingly, the relative amounts of mRNA for four of the five MHCs increase in tail muscle after T3 treatment of the tadpole, suggesting that repression of MHC gene expression at the protein level does not result from a decrease in the amount of MHC mRNAs. Rather, these results support the contention that the decreased synthesis of MHCs in the tail muscle of T3-treated tadpoles is caused by this hormone, either directly or indirectly, depressing the translation of the MHC mRNAs in this tissue. These results, coupled with the observation that the synthesis of soluble muscle proteins is depressed only in a transient fashion, suggest that T3 may be initiating the expression of a gene(s) that encodes a protein(s) responsible for inhibiting the translation of the MHCs and, perhaps, other structural proteins in the tadpole tail muscle. Whatever the case, the translational regulation of MHC synthesis occurs well before any degradation of the tail tissue is evident and appears to be one of the earliest events in the hormone-induced cell death program of the tadpole tail muscle. Dev. Genet. 24:151–164, 1999. © 1999 Wiley-Liss, Inc.

Cells rely heavily on cues from their extracellular environment and other cells to coordinate normal physiological processes, and the exchange of molecules via gap junctions has been suggested as an important avenue for cell-cell communication. Gap junctions are Found in virtually all mammalian tissues with the notable exception of adult skeletal muscle. However, since functional gap junctions have been detected during the early stages of muscle development, gap junctional intercellular communication (GJIC) may play an important role in myogenesis. In this study, GJIC in normal L6 myoblasts was inhibited using the known blockers 1-octanol and beta-glycyrrhetinic acid (beta-GA). Under differentiation promoting conditions, 16 cells fused io Form multinucleated myotubes, but when treated with either octanol or beta-GA, no fusion was observed. The expression of two muscle regulatory factors (MRFs), myogenin and MRF4, was examined in both the blocked and control cells. As expected, the activation of both the myogenin and MRF4 genes coincided with the onset of differentiation in the control 16 cells. Neither of these genes were turned on in the blocked cells, even when grown under low serum conditions. This inhibition of differentiation by octanol and beta-GA was reversible, since the activation of both MRF genes as well as myoblast fusion were observed when the blocking medium was replaced with normal differentiating medium. These results suggest thai intercellular communication via gap junctions plays an important role in skeletal muscle development and perhaps in the cell signaling events that trigger the activation of muscle-specific MRF genes. (C) 1997 Wiley-Liss, Inc.