972 resultados para Oral Biology and Oral Pathology


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Cobalamins are stored in high concentrations in the human liver and thus are available to participate in the regulation of hepatotropic virus functions. We show that cyanocobalamin (vitamin B12) inhibited the H(IV internal ribosome entry site (IRES)-dependent translation of a reporter gene in vitro in a dose-dependent manner without significantly affecting the cap-dependent mechanism. Vitamin B12 failed to inhibit translation by IRES elements from encephalomyocarditis virus (EMCV) or classical swine fever virus (CSFV), We also demonstrate a relationship between the total cobalamin concentration in human sera and HCV viral load (a measure of viral replication in the host), The mean viral load was two orders of magnitude greater when the serum cobalamin concentration was above 200 pM (P < 0.003), suggesting that the total cobalamin concentration in an HCV-infected liver is biologically significant in HCV replication.

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Cobalamins are stored in high concentrations in the human liver and thus are available to participate in the regulation of hepatotropic virus functions. We show that cyanocobalamin (vitamin B12) inhibited the HCV internal ribosome entry site (IRES)-dependent translation of a reporter gene in vitro in a dose-dependent manner without significantly affecting the cap-dependent mechanism. Vitamin B12 failed to inhibit translation by IRES elements from encephalomyocarditis virus (EMCV) or classical swine fever virus (CSFV). We also demonstrate a relationship between the total cobalamin concentration in human sera and HCV viral load (a measure of viral replication in the host). The mean viral load was two orders of magnitude greater when the serum cobalamin concentration was above 200 pM (P < 0.003), suggesting that the total cobalamin concentration in an HCV-infected liver is biologically significant in HCV replication.

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Several medical and dental schools have described their experience in the transition from conventional to digital microscopy in the teaching of general pathology and histology disciplines; however, this transitional process has scarcely been reported in the teaching of oral pathology. Therefore, the objective of the current study is to report the transition from conventional glass slide to virtual microscopy in oral pathology teaching, a unique experience in Latin America. An Aperio ScanScope® scanner was used to digitalize histological slides used in practical lectures of oral pathology. The challenges and benefits observed by the group of Professors from the Piracicaba Dental School (Brazil) are described and a questionnaire to evaluate the students' compliance to this new methodology was applied. An improvement in the classes was described by the Professors who mainly dealt with questions related to pathological changes instead of technical problems; also, a higher interaction with the students was described. The simplicity of the software used and the high quality of the virtual slides, requiring a smaller time to identify microscopic structures, were considered important for a better teaching process. Virtual microscopy used to teach oral pathology represents a useful educational methodology, with an excellent compliance of the dental students.

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Making diagnoses in oral pathology are often difficult and confusing in dental practice, especially for the lessexperienced dental student. One of the most promising areas in bioinformatics is computer-aided diagnosis, where a computer system is capable of imitating human reasoning ability and provides diagnoses with an accuracy approaching that of expert professionals. This type of system could be an alternative tool for assisting dental students to overcome the difficulties of the oral pathology learning process. This could allow students to define variables and information, important to improving the decision-making performance. However, no current open data management system has been integrated with an artificial intelligence system in a user-friendly environment. Such a system could also be used as an education tool to help students perform diagnoses. The aim of the present study was to develop and test an open case-based decisionsupport system.Methods: An open decision-support system based on Bayes' theorem connected to a relational database was developed using the C++ programming language. The software was tested in the computerisation of a surgical pathology service and in simulating the diagnosis of 43 known cases of oral bone disease. The simulation was performed after the system was initially filled with data from 401 cases of oral bone disease.Results: the system allowed the authors to construct and to manage a pathology database, and to simulate diagnoses using the variables from the database.Conclusion: Combining a relational database and an open decision-support system in the same user-friendly environment proved effective in simulating diagnoses based on information from an updated database.

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This project was comparing the accuracy of capturing the oral pathology diagnoses among different coding systems. 55 diagnoses were selected for comparison among 5 coding systems. The results of accuracy in capturing oral diagnoses are: AFIP (96.4%), followed by Read 99 (85.5%), SNOMED 98 (74.5%), ICD-9 (43.6%), and CDT-3 (14.5%). It shows that the currently used coding systems, ICD-9 and CDT-3, were inadequate, whereas the AFIP coding system captured the majority of oral diagnoses. In conclusion, the most commonly used medical and dental coding systems lack terms for the diagnosis of oral and dental conditions.

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Many lungfish of the tooth plated lineage, both fossil and living, are affected by dental and skeletal pathologies including dental caries, abscesses and cysts within the bone or tooth plate, osteopenia, bone hypertrophy, and malocclusion. These conditions, while influenced in part by structural relationships of soft and hard tissues in the tooth plates, jaw bones and surrounding oral tissues, can also be used as indicators of the kind of environment inhabited by the fish. The disease processes have specific structural consequences, related either to the pathology or to attempts to heal the damage, and usually alter the form and function of the tooth plate or bone. Consequently they can be distinguished from postmortem diagenetic or taphonomic effects, which alter the structure in less specific ways and show no sign of healing. Dental caries, the most common pathological condition in dipnoan dentitions, is recognisable in lungfish from the Devonian of Western Australia, the Tertiary of South Australia and the Northern Territory and from living lungfish in south east Queensland. Other pathologies have a more sporadic occurrence.

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The presence of Ursinia nana, an Anthemideae of South-African origin which has been introduced into the NE Iberian Peninsula, is reported for the fi rst time in Europe. The data offered cover its precise location, morphology, chromosome number, ecology and a population census, as well as its life cycle, fl oral structure, reproductive biology and fruit dispersal mechanisms. Of special note are the clear predominance of autogamy (geitonogamy) over xenogamy as a reproductive system and the large number of fruits produced with high and immediate germinative capacity. These characteristics permit rapid colonization by the introduced species, which can become invasive. However, fruit predation by the ant Messor barbarus points to a natural mechanism that helps regulate population growth and makes biological control possible. Finally its possibilities of expansion in the colonized area and of naturalization in the NE Iberian Peninsula are assessed.

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Breeding-system studies have been conducted with 38 of the approximately 800 species of Bignoniaceae, and self-incompatibility was found in 31 of these. In species for which the site of self-incompatibility barrier was studied, self-pollinated flowers consistently failed to develop into fruits, even though pollen tubes grew down to the ovary and penetrated most of the ovules. In this study, we have investigated the. oral biology and the breeding system in Jacaranda racemosa Chamisso, with hand-pollination experiments and the histology of post-pollination events. Flower anthesis lasted 1-3 days, and although the frequency of flower visitation was extremely low, natural pollination seemed to be effected mainly by medium-sized bees. Because the conspicuous staminodium favours eventual pollination by small bees, a possible role of the staminodium in the increase of potential pollinators is suggested. Hand-pollinations indicated that J. racemosa is a self-sterile species. Histological analysis of post-pollination events indicated the occurrence of a kind of late-acting self-incompatibility in which the processes of ovule penetration, fertilisation and endosperm initiation were slower in selfed than in crossed pistils. Until the time of self-pollinated pistil abscission, no signs of endosperm malfunction or proembryo development were observed in selfed pistils. Therefore, inbreeding depression is an unlikely explanation for self-sterility in J. racemosa.

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The nail is the largest skin appendage. It grows continuously through life in a non-cyclical manner; its growth is not hormone-dependent. The nail of the middle finger of the dominant hand grows fastest with approximately 0.1 mm/day, whereas the big toe nail grows only 0.03-0.05 mm/d. The nails' size and shape vary characteristically from finger to finger and from toe to toe, for which the size and shape of the bone of the terminal phalanx is responsible. The nail apparatus consists of both epithelial and connective tissue components. The matrix epithelium is responsible for the production of the nail plate whereas the nail bed epithelium mediates firm attachment. The hyponychium is a specialized structure sealing the subungual space and allowing the nail plate to physiologically detach from the nail bed. The proximal nail fold covers most of the matrix. Its free end forms the cuticle which seals the nail pocket or cul-de-sac. The dermis of the matrix and nail bed is specialized with a morphogenetic potency. The proximal and lateral nail folds form a frame on three sides giving the nail stability and allowing it to grow out. The nail protects the distal phalanx, is an extremely versatile tool for defense and dexterity and increases the sensitivity of the tip of the finger. Nail apparatus, finger tip, tendons and ligaments of the distal interphalangeal joint form a functional unit and cannot be seen independently. The nail organ has only a certain number of reaction patterns that differ in many respects from hairy and palmoplantar skin.

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