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Water current modelling and prediction techniques along coastal inlets have attracted growing concern in recent years. This is largely so because water current component continues to be a major contributor to movement of sediments, tracers and pollutants, and to a whole range of offshore applications in engineering, environmental observations, exploration and oceanography. However, most research works are lacking adequate methods for developing precise prediction models along the commodore channel in Lagos State. This research work presents water current prediction using Artificial Neural Networks (ANNs). The Back Propagation (BP) technique with feed forward architecture and optimized training algorithm known as Levenbergq-Marquardt was used to develop a Neural Network Water Current Prediction model-(NNWLM) in a MATLAB programming environment. It was passed through model sensitivity analysis and afterwards tested with data from the Commodore channel (Lagos Lagoon). The result revealed prediction accuracy ranging from 0.012 to 0.045 in terms of Mean Square Error (MSE) and 0.80 to 0.83 in terms of correlation coefficient (R-value). With this high performance, the Neural network developed in this work can be used as a veritable tool for water current prediction along the Commodore channel and in extension a wide variety of coastal engineering and development, covering sediment management program: dredging, sand bypassing, beach-contingency plans, and protection of beaches vulnerable to storm erosion and monitoring and prediction of long-term water current variations in coastal inlets. [ABSTRACT FROM AUTHOR]

Ameloblastoma is a benign odontogenic tumor of epithelial origin. It is locally aggressive with unlimited growth capacity and has a high potential for malignant transformation as well as metastasis. Ameloblastoma has no established preventive measures although majority of patients are between ages 30 and 60 years. Molecular and genetic factors that promote oncogenic transformation of odontogenic epithelium to ameloblastoma are strongly linked to dysregulation of multiple genes associated with mitogen‐activated protein kinase, sonic hedgehog, and WNT/β‐catenin signaling pathways. Treatment of ameloblastoma is focused on surgical resection with a wide margin of normal tissue because of its high propensity for locoregional invasion; but this is often associated with significant patient morbidity. The relatively high recurrence rate of ameloblastoma is influenced by the type of molecular etiological factors, the management approach, and how early the patient presents for treatment. It is expected that further elucidation of molecular factors that orchestrate pathogenesis and recurrence of ameloblastoma will lead to new diagnostic markers and targeted drug therapies for ameloblastoma. [ABSTRACT FROM AUTHOR]

In this work, 500 hourly water level tidal data were used to perform least squares tidal harmonic analysis. Eleven tidal constituents were used for the harmonic analysis. Astronomical arguments (v + u) and the nodal factor (f) were computed for each tidal constituent and at each observational period with a programme written in Matlab environment. The harmonic constants determined from the least squares tidal harmonic analysis were substituted into a tidal prediction model to predict hourly tidal data and tidal predictions at 5 minutes' intervals. Series of high and low water heights from the tidal predictions made at 5 minutes' intervals were determined and matched with their corresponding times. Autocorrelation at lags 1 to 30 for the residuals of the observed and predicted tidal data shows that there is no significant correlation in the range of the 30 lags. The series of residuals of the observed and predicted tidal data is therefore white noise. [ABSTRACT FROM AUTHOR]

The skeletal system is structurally and functionally unique. It can be referred to as connective tissue that lost its ability to resist mineralization as mineralization in any other connective tissues is heterotopic. In addition to providing support for muscular attachments, the skeletal system protects nerves and harbors the hematopoietic and mesenchymal stem cells within the bone marrow compartment. However, there are distinct phenotypic and functional differences between the orofacial skeleton compared to axial and appendicular skeleton. How different is the jaw bone from other non‐craniofacial bones? Interestingly, developmental, biological, and clinical outcomes point to distinctive features that make the jaw bone unique. [ABSTRACT FROM AUTHOR]

Fibrous dysplasia (FD) is a non-malignant condition caused by post-zygotic, activating mutations of the GNAS gene that results in inhibition of the differentiation and proliferation of bone-forming stromal cells and leads to the replacement of normal bone and marrow by fibrous tissue and woven bone. The phenotype is variable and may be isolated to a single skeletal site or multiple sites and sometimes is associated with extraskeletal manifestations in the skin and/or endocrine organs (McCune-Albright syndrome). The clinical behavior and progression of FD may also vary, thereby making the management of this condition difficult with few established clinical guidelines. This paper provides a clinically-focused comprehensive description of craniofacial FD, its natural progression, the components of the diagnostic evaluation and the multi-disciplinary management, and considerations for future research. [ABSTRACT FROM AUTHOR]

Presents the case of a man with a history of recurrent pathological fractures and progressive facial deformity. Finding that osseous fibrous dysplasia had enlarged his cranium and first cervical vertebrae; Evidence of a pituitary tumor; Diagnosis of McCune-Albright syndrome, a rare disease defined by a triad of skin spots, precocious puberty, and polyostotic fibrous dysplasia.

Hereditary diseases affecting the skeleton are heterogeneous in etiology and severity. Though many of these conditions are individually rare, the total number of people affected is great. These disorders often include dental-oral-craniofacial (DOC) manifestations, but the combination of the rarity and lack of in-depth reporting often limit our understanding and ability to diagnose and treat affected individuals. In this review, we focus on dental, oral, and craniofacial manifestations of rare bone diseases. Discussed are defects in 4 key physiologic processes in bone/tooth formation that serve as models for the understanding of other diseases in the skeleton and DOC complex: progenitor cell differentiation (fibrous dysplasia), extracellular matrix production (osteogenesis imperfecta), mineralization (familial tumoral calcinosis/hyperostosis hyperphosphatemia syndrome, hypophosphatemic rickets, and hypophosphatasia), and bone resorption (Gorham-Stout disease). For each condition, we highlight causative mutations (when known), etiopathology in the skeleton and DOC complex, and treatments. By understanding how these 4 foci are subverted to cause disease, we aim to improve the identification of genetic, molecular, and/or biologic causes, diagnoses, and treatment of these and other rare bone conditions that may share underlying mechanisms of disease., (© International & American Associations for Dental Research.)

Unlabelled: Resistance to treatment and the appearance of secondary tumors in head and neck squamous cell carcinomas (HNSCC) have been attributed to the presence of cells with stem-cell-like properties in the basal layer of the epithelium at the site of the lesion. In this study, we tested the hypothesis that these putative cancer stem cells (CSC) in HNSCC could be specifically targeted and inhibited. We found that 9 of 10 head and neck tumor biopsies contained a subpopulation of cells that expressed CD133, an unusual surface-exposed membrane-spanning glycoprotein associated with CSC. A genetically modified cytolethal distending toxin (Cdt), from the periodontal pathogen Aggregatibacter actinomycetemcomitans, was conjugated to an anti-human CD133 monoclonal antibody (MAb). The Cdt-MAb complex preferentially inhibited the proliferation of CD133(+) cells in cultures of established cell lines derived from HNSCC. Inhibition of the CD133(+) cells was rate- and dose-dependent. Saturation kinetics indicated that the response to the Cdt-MAb complex was specific. Healthy primary gingival epithelial cells that are native targets of the wild-type Cdt were not affected. Analysis of these data provides a foundation for the future development of new therapies to target CSC in the early treatment of HNSCC., Abbreviations: Cdt, cytolethal distending toxin; CSC, cancer stem cells; HNSCC, head and neck squamous cell carcinoma; MAb, monoclonal antibody.

Objectives: Bisphosphonates commonly used to treat osteoporosis, Paget's disease, multiple myeloma, hypercalcemia of malignancy and osteolytic lesions of cancer metastasis have been associated with bisphosphonate-associated jaw osteonecrosis (BJON). The underlying pathogenesis of BJON is unclear, but disproportionate bisphosphonate concentration in the jaw has been proposed as one potential etiological factor. This study tested the hypothesis that skeletal biodistribution of intravenous bisphosphonate is anatomic site-dependent in a rat model system., Materials and Methods: Fluorescently labeled pamidronate was injected intravenously in athymic rats of equal weights followed by in vivo whole body fluorimetry, ex vivo optical imaging of oral, axial, and appendicular bones and ethylenediaminetetraacetic acid bone decalcification to assess hydroxyapatite-bound bisphosphonate., Results: Bisphosphonate uptake and bisphosphonate released per unit calcium were similar in oral and appendicular bones but lower than those in axial bones. Hydroxyapatite-bound bisphosphonate liberated by sequential acid decalcification was the highest in oral, relative to axial and appendicular bones (P < 0.05)., Conclusions: This study demonstrates regional differences in uptake and release of bisphosphonate from oral, axial, and appendicular bones of immune deficient rats., (© 2010 John Wiley & Sons A/S.)

beta-Catenin signaling is required for embryonic tooth morphogenesis and promotes continuous tooth development when activated in embryos. To determine whether activation of this pathway in the adult oral cavity could promote tooth development, we induced mutation of epithelial beta-catenin to a stabilized form in adult mice. This caused increased proliferation of the incisor tooth cervical loop, outpouching of incisor epithelium, abnormal morphology of the epithelial-mesenchymal junction, and enhanced expression of genes associated with embryonic tooth development. Ectopic dental-like structures were formed from the incisor region following implantation into immunodeficient mice. Thus, forced activation of beta-catenin signaling can initiate an embryonic-like program of tooth development in adult rodent incisor teeth.

Objective: Intervertebral disc (IVD) degeneration is a major health concern in the United States. Replacement of the nucleus pulposus (NP) with injectable biomaterials represents a potential treatment strategy for IVD degeneration. The objective of this study was to characterize the extracellular matrix (ECM) assembly and functional properties of NP cell-encapsulated, photo-crosslinked alginate hydrogels in comparison to ionically crosslinked alginate constructs., Methods: Methacrylated alginate was synthesized by esterification of hydroxyl groups with methacrylic anhydride. Bovine NP cells were encapsulated in alginate hydrogels by ionic crosslinking using CaCl(2) or through photo-crosslinking upon exposure to long-wave UV light in the presence of a photoinitiator. The hydrogels were evaluated in vitro by gross and histological analysis and in vivo using a murine subcutaneous pouch model. In vivo samples were analyzed for gene expression, ECM localization and accumulation, and equilibrium mechanical properties., Results: Ionically crosslinked hydrogels exhibited inferior proteoglycan accumulation in vitro and were unable to maintain structural integrity in vivo. In further studies, photo-crosslinked alginate hydrogels were implanted for up to 8 weeks to examine NP tissue formation. Photo-crosslinked hydrogels displayed temporal increases in gene expression and assembly of type II collagen and proteoglycans. Additionally, hydrogels remained intact over the duration of the study and the equilibrium Young's modulus increased from 1.24+/-0.09 kPa to 4.31+/-1.39 kPa, indicating the formation of functional matrix with properties comparable to those of the native NP., Conclusions: These findings support the use of photo-crosslinked alginate hydrogels as biomaterial scaffolds for NP replacement.

The masticatory apparatus absorbs high occlusal forces, but uncontrolled parafunctional or orthodontic forces damage periodontal ligament (PDL), cause pulpal calcification, pulp necrosis and tooth loss. Morphology and functional differentiation of connective tissue cells can be controlled by mechanical stimuli but effects of uncontrolled forces on intra-pulpal homeostasis and ability of dental pulp stem cells (DPSCs) to withstand direct external forces are unclear. Using dynamic hydrostatic pressure (HSP), we tested the hypothesis that direct HSP disrupts DPSC survival and odontogenic differentiation. DPSCs from four teenage patients were subjected to HSP followed by assessment of cell adhesion, survival and recovery capacity based on odontogenic differentiation, mineralization and responsiveness to bone morphogenetic protein-2 (BMP-2). HSP down-regulated DPSC adhesion and survival but promoted differentiation by increasing mineralization, in vivo hard tissue regeneration and BMP-2 responsiveness despite reduced cell numbers. HSP-treated DPSCs displayed enhanced odontogenic differentiation, an indication of favorable recovery from HSP-induced cellular stress.

Objective: Fibrous dysplasia (FD) is a rare skeletal disease caused by activating GNAS1 gene mutations often found in association with the McCune-Albright syndrome (MAS). Multiple bones may be affected in FD, including maxilla and mandible. Patients with MAS have different endocrinopathies that can further influence bone metabolism. The purposes of this cross-sectional study are to characterize FD panoramic radiographic patterns, and to evaluate the effects of age, endocrinopathies and renal phosphate wasting on radiographic characteristics of maxillo-mandibular FD in MAS., Subjects and Methods: Fifty-one consecutive MAS patients were screened and panoramic radiographs of 43 patients with craniofacial FD were evaluated and analyzed for FD involvement. Clinical chemistries were evaluated for associations between radiographic patterns and age, endocrinopathies or renal phosphate wasting using Fisher's Exact Test., Results: Four types of radiographic changes were observed: ground glass (granular/condensed trabeculae), radiolucent (lytic), mixed radiolucent/radio-opaque (mixed density) or radio-opaque (sclerotic). Masking or displacement of the maxillary sinus (range: 77.8-86.4%) and mandibular canal (range: 55.6-75.0%) were prevalent in FD sites. Sixty-three percent of the MAS patients had multiple dysregulated endocrine/metabolic functions, the most common were hyperthyroidism, precocious puberty and renal phosphate wasting. There were no statistically significant associations between radiographic patterns and age, endocrinopathies or renal phosphate wasting., Conclusions: Maxillo-mandibular FD images in panoramic radiographs fall within a spectrum of four different patterns. Patients with facial asymmetry and any of these radiographic patterns should be promptly referred for further radiographic tests and endocrine evaluation if MAS is suspected.

Human submandibular/sublingual saliva contains a protein that promotes adhesion of Streptococcus mutans JBP serotype-c to spheroidal hydroxyapatite in vitro. A high molecular-weight (250,000-300,000 Da) adhesion-promoting protein (APP) was purified by Trisacryl 2000 M gel-filtration chromatography and gel electroelution before it was partially characterized. Lectin blotting identified that the terminal carbohydrates include N-acetyl glucosamine-beta 1-4-N-acetylglucosamine, galactose and galactose-beta 1-3-N-acetyl galactosamine. Antibodies to APP demonstrated no difference in the immunoreactive pattern of APP from saliva of caries-active or caries-resistant individuals belonging to four different ethnic groups: Asian, African-American, Hispanic or Caucasian. No immunological similarities to salivary mucins or parotid agglutinins were detected by Western blotting using immuno-cross-reactivity as a criterion. APP appears to be a unique protein found in submandibular/sublingual saliva. Understanding such a protein could help prevent S. mutans attachment to the enamel surface.