351 research outputs found

    Peripheral calcifying cystic odontogenic tumour of the maxillary gingiva

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    BACKGROUND: Odontogenic tumors are lesions that are derived from remnants of the components of the developing tooth germ. The calcifying cystic odontogenic tumor or calcifying odontogenic cyst is a benign cystic neoplasm of odontogenic origin that is characterized by an ameloblastoma-like epithelium and ghost cells. Calcifying cystic odontogenic tumor may be centrally or peripherally located, and its ghost cells may exhibit calcification, as first described by Gorlin in 1962. Most peripheral calcifying cystic odontogenic tumors are located in the anterior gingiva of the mandible or maxilla. CASE PRESENTATION: Authors report a rare case of a peripheral calcifying cystic odontogenic tumor of the maxillary gingiva. A 39-year-old male patient presented with a fibrous mass on the attached buccal gingiva of the upper left cuspid teeth. It was 0.7-cm-diameter, painless and it was clinically diagnosed as a peripheral ossifying fibroma. After an excisional biopsy, the diagnosis was peripheric calcifying cystic odontogenic tumor. The patient was monitored for five years following the excision, and no recurrence was detected. CONCLUSIONS: All biopsy material must be sent for histological examination. If the histological examination of gingival lesions with innocuous appearance is not performed, the frequency of peripheral calcifying cystic odontogenic tumor and other peripheral odontogenic tumors may be underestimated

    Human boday damage analysis by SPH method

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    In order to evaluate the biological properties of a human head response at impacts accidents, authors have been developing the SPH (Smooth Particle Hydrodynamics) particle model of the whole human head and analyzing dynamically in simulating high velocity impact accident. In this report, authors have shown how to make a particle model of a head from real CT scan images directly and how to render the model in computer graphics using GPU and the algorithm for elastic-plastic analysis of a head model. The results from the simulations could explain one of injury mechanisms of a human head in actual car accidents

    A Genome-wide Approach to Identify the Genes Involved in Biofilm Formation in E. coli

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    Biofilm forming cells are distinctive from the well-investigated planktonic cells and exhibit a different type of gene expression. Several new Escherichia coli genes related to biofilm formation have recently been identified through genomic approaches such as DNA microarray analysis. However, many others involved in this process might have escaped detection due to poor expression, regulatory mechanism, or genetic backgrounds. Here, we screened a collection of single-gene deletion mutants of E. coli named ‘Keio collection’ to identify genes required for biofilm formation. Of the 3985 mutants of non-essential genes in the collection thus examined, 110 showed a reduction in biofilm formation nine of which have not been well characterized yet. Systematic and quantitative analysis revealed the involvement of genes of various functions and reinforced the importance in biofilm formation of the genes for cell surface structures and cell membrane. Characterization of the nine mutants of function-unknown genes indicated that some of them, such as yfgA that genetically interacts with a periplasmic chaperone gene surA together with yciB and yciM, might be required for the integrity of outer membrane

    Necrotizing sialometaplasia as a cause of a non-ulcerated nodule in the hard palate: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Necrotizing sialometaplasia is a benign, self-limiting and rare inflammatory disease which, on clinical and histological examination, mimics malignant neoplasms.</p> <p>Case report</p> <p>We report the case of a healthy 25-year-old Caucasian woman with a three-week history of a painless lump on her hard palate. Oral examination revealed a nodule consisting of two lobules on the right side that measured 2.5 cm. Her mucosa was normal in color and a fluctuant area was detected in the posterior region upon palpation. Our patient was submitted to incisional biopsy and histopathological examination. The histological diagnosis was necrotizing sialometaplasia. The lesion had healed spontaneously after 30 days, with observed signs of involution of the nodule.</p> <p>Conclusion</p> <p>Histopathological examination is necessary for the diagnosis of necrotizing sialometaplasia because the clinical features of this condition can mimic other diseases, particularly malignant neoplasms.</p

    Elastic Band Causing Exfoliation of the Upper Permanent Central Incisors

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    Objective. This study reports a case in which elastic band use culminated in the loss of the incisors. Case Report. An 11-year-old white girl was seen complaining of pain, with purulent discharge and severe tooth mobility. The bone destruction detected radiographically in the region, despite its single location and absence in posterior quadrants of the maxilla and/or mandible, was similar to that observed in Langerhans cell disease. To our surprise, an elastic band involving the midportion of the roots of the two upper central incisors was found during biopsy. The debris was removed and a metal wire was placed in permanent maxillary right and left incisors. The patient was followed up, but no improvement in tooth mobility was observed. Bone loss increased, and internal resorption and root exposure occurred, which culminated in the extraction of permanent maxillary right and left incisors. Conclusion. The present case highlights the fact that professionals sometimes are confronted by anamnestic reports never seen before

    Kinetic Model For Triglyceride Hydrolysis Using Lipase:Review

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    Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials in food and cosmetic industries such as diacylglycerol, monoacylglycerol, glycerol and fatty acid. In order to design a reactor for utilizing this reaction on industrial scale, constructing a kinetic model is important. Since the substrates are oil and water, the hydrolysis takes place at oil-water interface. Furthermore, the triglyceride has three ester bonds, so that the hydrolysis stepwise proceeds. Thus, the reaction mechanism is very complicated. The difference between the interfacial and bulk concentrations of the enzyme, substrates and products, and the interfacial enzymatic reaction mechanism should be considered in the model

    Treatment of Oral Vascular Malformations with Ethamolin: A Report of Two Cases

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    A hemangioma is a benign vascular neoplasm, relatively common in the head and neck. In the oral region, it affects the tongue, gums, mucosa, palate, and lip. Its size can vary from millimeters to centimeters, characterized as a purplish or reddish lesion. The present study aims to present two clinical cases of hemangiomas, the first of a male patient treated by sclerotherapy and the second of a female patient in which she was treated with ethamolin and later surgical treatment. It was concluded that sclerotherapy, in addition to being a safe treatment, managed to drastically reduce the initial size of the lesions present in this article
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