906 resultados para Oral cavit


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Background and Objectives: Several studies have suggested that low-level laser therapy (LLLT) can ameliorate oral mucositis, however, the mechanisms involved are not well understood. The aim of this study was to investigate the mechanisms of action of LLLT on chemotherapy-induced oral mucositis, as related to effects on collagen expression and inflammation Materials and Methods: A hamster cheek pouch model of oral mucositis was used with all animals receiving intraperitoneal 5-fluorouracil, followed by surface irritation. Animals were randomly allocated into three groups, and treated with an InGaAIP diode laser at a wavelength of 660 nm and output power of 35 or 100 mW laser, or no laser Clinical severity of mucositis was assessed at four time-points by a blinded examiner Buccal pouch tissue was harvested from a subgroup of animals in each group at four time-points. Collagen was qualitatively and quantitatively evaluated after picrosinus staining. The density of the neutrophil infiltrate was also scored Results: Peak clinical severity of mucositis was reduced in the 35 mW laser group as compared to the 100 mW and control groups The reduced peak clinical severity of mucositis in the 35 mW laser group was accompanied by a decrease in the number of neutrophils and an increase in the proportion of mature collagen as compared to the other two groups. The total quantity of collagen was significantly higher in the control (no laser) group at the day 11 time-point, as compared to the 35 mW laser group, consistent with a more prolonged inflammatory response in the control group. Conclusion: This study supports two mechanisms of action for LLLT in reducing mucositis severity. The increase in collagen organization in response to the 35 mW laser indicates that LLLT promotes wound healing In addition, LLLT also appears to have an anti-inflammatory effect, as evidenced by the reduction in neutrophil infiltrate Lasers Surg Med 42 546-552, 2010. (C) 2010 Wiley-Liss, Inc.

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The aim of this study was to investigate the mechanisms whereby low-intensity laser therapy may affect the severity of oral mucositis. A hamster cheek pouch model of oral mucositis was used with all animals receiving intraperitoneal 5-fluorouracil followed by surface irritation. Animals were randomly allocated into three groups and treated with a 35 mW laser, 100 mW laser, or no laser. Clinical severity of mucositis was assessed at four time-points by a blinded examiner. Buccal pouch tissue was harvested from a subgroup of animals in each group at four time-points. This tissue was used for immunohistochemistry for cyclooxygenase-2 (COX-2), vascular endothelial growth factor (VEGF), and factor VIII (marker of microvessel density) and the resulting staining was quantified. Peak severity of mucositis was reduced in the 35 mW laser group as compared to the 100 mW laser and control groups. This reduced peak clinical severity of mucositis in the 35 mW laser group was accompanied by a significantly lower level of COX-2 staining. The 100 mW laser did not have an effect on the severity of clinical mucositis, but was associated with a decrease in VEGF levels at the later time-points, as compared to the other groups. There was no clear relationship of VEGF levels or microvessel density to clinical mucositis severity. The tissue response to laser therapy appears to vary by dose. Low-intensity laser therapy appears to reduce the severity of mucositis, at least in part, by reducing COX-2 levels and associated inhibition of the inflammatory response.

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Although the oral cavity is easily accessible to inspection, patients with oral cancer most often present at a late stage, leading to high morbidity and mortality. Autofluorescence imaging has emerged as a promising technology to aid clinicians in screening for oral neoplasia and as an aid to resection, but current approaches rely on subjective interpretation. We present a new method to objectively delineate neoplastic oral mucosa using autofluorescence imaging. Autofluorescence images were obtained from 56 patients with oral lesions and 11 normal volunteers. From these images, 276 measurements from 159 unique regions of interest (ROI) sites corresponding to normal and confirmed neoplastic areas were identified. Data from ROIs in the first 46 subjects were used to develop a simple classification algorithm based on the ratio of red-to-green fluorescence; performance of this algorithm was then validated using data from the ROIs in the last 21 subjects. This algorithm was applied to patient images to create visual disease probability maps across the field of view. Histologic sections of resected tissue were used to validate the disease probability maps. The best discrimination between neoplastic and nonneoplastic areas was obtained at 405 nm excitation; normal tissue could be discriminated from dysplasia and invasive cancer with a 95.9% sensitivity and 96.2% specificity in the training set, and with a 100% sensitivity and 91.4% specificity in the validation set. Disease probability maps qualitatively agreed with both clinical impression and histology. Autofluorescence imaging coupled with objective image analysis provided a sensitive and noninvasive tool for the detection of oral neoplasia.

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BACKGROUND: Optical spectroscopy is a noninvasive technique with potential applications for diagnosis of oral dysplasia and early cancer. In this study, we evaluated the diagnostic performance of a depth-sensitive optical spectroscopy (DSOS) system for distinguishing dysplasia and carcinoma from non-neoplastic oral mucosa. METHODS: Patients with oral lesions and volunteers without any oral abnormalities were recruited to participate. Autofluorescence and diffuse reflectance spectra of selected oral sites were measured using the DSOS system. A total of 424 oral sites in 124 subjects were measured and analyzed, including 154 sites in 60 patients with oral lesions and 270 sites in 64 normal volunteers. Measured optical spectra were used to develop computer-based algorithms to identify the presence of dysplasia or cancer. Sensitivity and specificity were calculated using a gold standard of histopathology for patient sites and clinical impression for normal volunteer sites. RESULTS: Differences in oral spectra were observed in: (1) neoplastic versus nonneoplastic sites, (2) keratinized versus nonkeratinized tissue, and (3) shallow versus deep depths within oral tissue. Algorithms based on spectra from 310 nonkeratinized anatomic sites (buccal, tongue, floor of mouth, and lip) yielded an area under the receiver operating characteristic curve of 0.96 in the training set and 0.93 in the validation set. CONCLUSIONS: The ability to selectively target epithelial and shallow stromal depth regions appeared to be diagnostically useful. For nonkeratinized oral sites, the sensitivity and specificity of this objective diagnostic technique were comparable to that of clinical diagnosis by expert observers. Thus, DSOS has potential to augment oral cancer screening efforts in community settings. Cancer 2009;115:1669-79. (C) 2009 American Cancer Society.

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Liposomes have been used as adjuvants since 1974. One major limitation for the use of liposomes in oral vaccines is the lipid structure instability caused by enzyme activities. Our aim was to combine liposomes that could encapsulate antigens (i.e., Dtxd, diphtheria toxoid) with chitosan, which protects the particles and promotes mucoadhesibility. We employed physical techniques to understand the process by which liposomes (SPC: Cho, 3: 1) can be sandwiched with chitosan (Chi) and stabilized by PVA (poly-vinylic alcohol), which are biodegradable, biocompatible polymers. Round, smooth-surfaced particles of REVs-Chi (reversed-phase vesicles sandwiched by Chi) stabilized by PVA were obtained. The REVs encapsulation efficiencies (Dtxd was used as the antigen) were directly dependent on the Chi and PVA present in the formulation. Chi adsorption on the REVs surface was accompanied by an increase of zeta-potential. In contrast, PVA adsorption on the REVs-Chi surface was accompanied by a decrease of zeta-potential. The presence of Dtxd increased the Chi surface-adsorption efficiency. The PVA affinity by mucine was 2,000 times higher than that observed with Chi alone and did not depend on the molecule being in solution or adsorbed on the liposomal surface. The liberation of encapsulated Dtxd was retarded by encapsulation within REVs-Chi-PVA. These results lead us to conclude that these new, stabilized particles were able to be adsorbed by intestinal surfaces, resisted degradation, and controlled antigen release. Therefore, REVs-Chi-PVA particles can be used as an oral delivery adjuvant.

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Preclinical investigations can start with preliminary in vitro studies before using animal models. Following this approach, the number of animals used in preclinical acute toxicity testing can be reduced. In this study, we employed an in-house validated in vitro cytotoxicity test based on the Spielmann approach for toxicity evaluation of the lignan grandisin, a candidate anticancer agent, and its major metabolite. the 4-O-demethylgrandisin, by neutral red uptake (NRU) assay, on mouse fibroblasts Balb/c 3T3 cell line. Using different concentrations of grandisin and its major metabolite (2.31; 1.16; 0.58; 0.29; 0.14; 0.07; 0.04; 0.002 mu M) in Balb/c 3T3-A31 NRU cytotoxicity assay, after incubation for 48 h, we obtained IC(50) values for grandisin and its metabolite of 0.078 and 0.043 mu M, respectively. The computed LD(50) of grandisin and 4-O-demethylgrandisin were 617.72 and 429.95 mg/kg, respectively. Both were classified under the Globally Harmonized System as category 4. Since pharmacological and toxicological data are crucial in the developmental stages of drug discovery, using an in vitro assay we demonstrated that grandisin and its metabolite exhibit distinct toxicity profiles. Furthermore, results presented in this work can contribute to reduce the number of animals required in subsequent pharmacological/toxicological studies. (C) 2010 Elsevier GmbH. All rights reserved.

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The Activist Women's Voices Oral History Project, funded by AT&T, the Ford Foundation, the Ms. Foundation for Education and Communication, and the New York Council for Humanities, is committed to documenting the voices of unheralded activist women in community-based organizations in New York City. The archive was established in 1995 under the direction of Professors Joyce Gelb and Patricia Laurence with the aim of creating linkages between activist women in the New York City community and student and faculty researchers at the City University of New York.

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This presentation tells how podcasts can be used to enhance the learning experience of English as a Second Language (ESL) students registered in a content-based language immersion program. The students were placed in groups of four and asked to prepare an oral presentation. The topics of the presentations included Financial Aid, College Courses and Course Schedules and Academic Policies. Each presentation was podcasted to give students an opportunity for self-evaluation and feedback.

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Implantatförankrad protetik har blivit ett vanligt behandlingsalternativ vid tandförlust.Tänder som förlorats på grund av karies, aplasi, trauma (olycksfall) eller parodontit (tandlossning) kan idag på många patienter ersättas med hjälp av implantat det vill säga en konstgjord tandrot av titan. Ett eller flera implantat opereras/installeras in i käkbenet och förses därefter med en krona, en bro eller en protes.Vävnaden runt implantatet kan drabbas av infektion på liknande sätt som vävnaden runt naturliga tänder och kallas då periimplantit. Detta är en reversibel inflammatorisk process i mjukvävnaden runt ett implantat med förlust av benvävnad.Syftet med studien var att beskriva förekomst av periimplantit hos patienter som erhållit implantat åren 2000-2001 vid Centrum Oral Rehabilitering, Parodontologi, samt förekomst av eventuella skillnader i periimplantit med avseende på rökvanor, kön och tidigare parodontal diagnos.Studien var en retrospektiv, beskrivande jämförande journalstudie.Totalt granskades 100 journaler, 80 journaler exkluderades då inte röntgenbilder togs tre år efter fixtur/implantat installation. Resultatet visade att 13 var kvinnor (65 %), 8 rökare (40 %) och 11 (55 %) personer hade remitterats för tidigare förekomst av parodontit.63 implantat installerades på 20 patienter. Periimplantit uppstod vid 8 implantat (13 %). Dessa implantat fanns hos 8 olika patienter, 5 var kvinnor, 5 rökare och 5 hade remitterats för parodontal diagnos. Något statistiskt samband kunde inte påvisas mellan förekomst av periimplantit och kön, rökvanor eller tidigare parodontal diagnos.Konklusionen: Förekomst av periimplantit under åren 2000-2001 var 13 %, vilket stämmer med tidigare studier.

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Syftet med studien var att undersöka om det förekommer skillnader i upplevelsen av oral hälsorelaterad livskvalitet hos personer som överlevt akut hjärtinfarkt jämfört med personer som inte har haft hjärtinfarkt.Studien genomfördes under åren 2001-2002 och alla personer som sökte vård vid ett mellanstort sjukhus i södra Sverige med diagnosen akut hjärtinfarkt och som överlevt infarkten inkluderades i studien. Kontrollgruppen bestod av vänner (n=69) till personerna som hade överlevt akut hjärtinfarkt samt personer (n=90) från en tidigare undersökning från samma sjukhus och som överensstämde i kön, ålder, socioekonomisk bakgrund och rökstatus. Totalt deltog 154 personer som överlevt akut hjärtinfarkt och 159 personer i kontrollgruppen.Mätinstrumentet som användes i studien var Oral Health Impact Profile (OHIP), vilket är ett frågeformulär för att mäta självupplevd munhälsorelaterad livskvalitet. Formuläret ger mått på dysfunktion, obehag och funktionshinder relaterade till munhålan. OHIP består av 49 frågor, fördelade över sju dimensioner: funktionsbegränsningar, fysisk smärta, psykiska problem, fysisk oförmåga, psykisk oförmåga, social oförmåga och handikapp.Resultatet visar att inga statistiskt säkerställda skillnader fanns mellan de personer som överlevt akut hjärtinfarkt och kontrollgruppen i de sju dimensionerna i OHIP. Det var få personer som upplevde besvär från munhålan som påverkade deras livskvalitet i båda grupperna. I denna studie framkom endast en statistisk säkerställd skillnad mellan de undersökta grupperna i påståendet att de upplevde att mat fastnat mellan tänderna (p-värde 0.024), vilket kan tyda på att användbarheten för OHIP är litet på denna patientgruppen. Fler studier krävs för att undersöka skillnader i upplevelsen av oral hälsorelaterad livskvalitet hos personer som överlevt akut hjärtinfarkt jämfört med personer som inte har haft hjärtinfarkt.

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This dissertation research aims to analyze the material Ejercicios Amigos Dos used by students learning Spanish as a foreign language in a Swedish school. Specifically, it examines the place of speaking skills, in the context of basic language skills. This study was an exploratory and descriptive analysis of the material Ejercicios Amigos Dos.Qualitative method used was action research, which was based on the real needs of the author of this study to enhance their teaching.Sheet one and Sheet two containing educational criteria for the analysis of teaching materials were used to measure the place of speaking skills.The main findings in the analysis showed that speaking skills are taken into account in the teaching material, however there are some micro skills missing. Speaking skills do not take a prominent role in the teaching material. Writing skills are emphasized to a greater extent.

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La importancia de la dimensión afectiva que acompaña el proceso de adquisición de lenguas extranjeras es indiscutible. Sin embargo, a pesar de esta realidad, y de la evolución de los enfoques comunicativos como métodos de enseñanza de idiomas, la literatura continúa asegurando la existencia de aprensión lingüística en el aula y su efecto debilitador en el proceso de aprendizaje de una nueva lengua. Este estudio tiene como objetivo examinar cómo el aprendiz experimenta la variable de la ansiedad al expresarse oralmente y en qué medida el profesorado de lenguas extranjeras puede lograr crear condiciones en la clase que reduzcan los niveles de ansiedad. En este trabajo utilizamos la revisión sistemática de literatura como estrategia de investigación, un método que constituye una buena herramienta, permitiéndonos sintetizar coherentemente, de forma rigurosa, los resultados de los estudios empíricos sobre el fenómeno de la ansiedad. Los análisis revelan, en primer lugar, que los síntomas experimentados por aprendices de una nueva lengua suelen manifestarse en cada uno de los niveles que integran al individuo, en un nivel emocional, psicológico, fisiológico, de comportamiento y psicopedagógico; en segundo lugar, los investigadores plantean diversas estrategias a nivel psicológico, pedagógico y socio ambiental con el objetivo principal de incrementar en el aprendiz una serie de recursos personales para hacer frente a la ansiedad. Comentamos las implicancias pedagógicas de estos resultados para una mejor comprensión de la ansiedad y del aprendizaje de una lengua extranjera.

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OBJECTIVES: The aim of the Tromstannen - Oral Health in Northern Norway (TOHNN) study was to investigate oral health and dental-related diseases in an adult population. This article provides an overview of the background of the study and a description of the sample characteristics and methods employed in data collection. STUDY DESIGN: Cross-sectional population-based study including a questionnaire and clinical dental examination. METHODS: A randomly selected sample of 2,909 individuals (20-79 years old) drawn from the population register was invited to participate in the study. The data were collected between October 2013 and November 2014 in Troms County in northern Norway. The questionnaire focused on oral health-related behaviours and attitudes, oral health-related quality of life, sense of coherence, dental anxiety and symptoms from the temporomandibular joint. The dental examinations, including radiographs, were conducted by 11 dental teams in 5 dental offices. The examination comprised of registration of dental caries, full mouth periodontal status, temporomandibular disorders, mucosal lesions and height and weight. The participants were grouped by age (20-34, 35-49, 50-64 and 65-79) and ethnicity (Norwegian, Sámi, other European and other world). RESULTS: From the original sample of 2,909 individuals, 1,986 (68.3%) people participated, of whom 1,019 (51.3%) were women. The highest attendance rate was among women 20-34 years old (80.3%) and the lowest in the oldest age group of women (55.4%). There was no difference in response rate between rural and urban areas. There was a positive correlation between population size and household gross income (p < 0.001) and education level (p < 0.001). The majority of Sámi resided in smaller municipalities. In larger cities, most participants used private dental health care services, whereas, in rural areas, most participants used the public dental health care service. CONCLUSION: The TOHNN study has the potential to generate new knowledge on a wide range of oral health conditions beneficial to the population in Troms County. Due to the high participation rate, generalization both nationally and to the circumpolar area ought to be possible.