971 resultados para BIOMASA RESIDUAL


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Electroacoustic stimulation is an excellent option for people with residual hearing in the low frequencies, who obtain insufficient benefit with hearing aids. To be effective, the subject's residual hearing should be preserved during cochlear implant surgery. To evaluate the hearing preservation in patients that underwent implant placement and to compare the results in accordance with the approach to the inner ear. 19 subjects underwent a soft surgical technique, and the electrode MED-EL FLEX™ EAS, designed to be atraumatic, was used. We evaluated pre- and postoperative tonal audiometric tests with an average of 18.4 months after implantation, to measure the rate of hearing preservation. 17 patients had total or partial preservation of residual hearing; 5 had total hearing preservation and two individuals had no preservation of hearing. The insertion of the electrode occurred through a cochleostomy in 3 patients, and in 2 of these there was no hearing preservation; the other 16 patients experienced electrode insertion through a round window approach. All patients benefited from the cochlear implant, even those who are only using electrical stimulation. The hearing preservation occurred in 89.4% of cases. There was no significant difference between the forms of inner ear approach.

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To evaluate pathologic features with implications on surgical radicality in women treated with radical hysterectomy and pelvic lymphadenectomy for cervical cancer stage IA1 with lymph vascular space invasion (LVSI) and stage IA2 by correlating findings in conization and hysterectomy specimens. Women with cervical cancer stage IA1 with LVSI and stage IA2 diagnosed by loop electrosurgical excisional procedure or cold knife conization were treated with radical hysterectomy and pelvic lymphadenectomy from January 1999 to December 2011 in 2 institutions. Fifty patients were enrolled: 40 with stage IA2 and 10 with stage IA1 with LVSI. Median age was 43 (30-67) years. All patients underwent cervical conization for diagnosis (45 loop electrosurgical excisional procedure, 5 cold knife). Lymph vascular space invasion was detected in 15 patients (30%). Two patients had positive pelvic nodes. No parametrial involvement was detected in the entire cohort. Positive margins were present in 35 patients, and residual disease was detected in 22 patients (44%). Positive margins predicted residual disease at radical hysterectomy (P = 0.02). Medium follow-up time was 51 months. One patient developed a pelvic recurrence, and there were no disease-related deaths. Patients with positive margins in cone biopsy specimens have an increased risk of residual disease at radical hysterectomy and require careful evaluation before conservative surgery. Pelvic lymph node evaluation is essential because lymph node metastasis may occur even in early stages. The lack of parametrial invasion in this study reinforces the knowledge that the select group of patients with microinvasive cervical carcinoma stages IA1 LVSI and stage IA2 have a very low risk of parametrial infiltration. Less radical surgery can be carefully considered for these patients.

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This study investigated the presence of target bacterial species and the levels of endotoxins in teeth with apical periodontitis. Levels of inflammatory mediators (interleukin [IL]-1β and tumor necrosis factor [TNF]-α) were determined after macrophage stimulation with endodontic content after different phases of endodontic therapy using different irrigants. Thirty primarily infected root canals were randomly assigned into 3 groups according to the irrigant used for root canal preparation (n = 10 per group): GI: 2.5% sodium hypochlorite, GII: 2% chlorhexidine gel, and GIII (control group): saline solution. Root canal samples were taken by using paper points before (s1) and after root canal instrumentation (s2), subsequently to 17% EDTA (s3), after 30 days of intracanal medication (Ca[OH]2 + saline solution) (s4), and before root canal obturation (s5). Polymerase chain reaction (16S recombinant DNA) and limulus amebocyte lysate assay were used for bacterial and endotoxin detection, respectively. Macrophages were stimulated with the root canal contents for IL-1β/TNF-α measurement using enzyme-linked immunosorbent assay. Porphyromonas gingivalis (17/30), Porphyromonas endodontalis (15/30), and Prevotella nigrescens (11/30) were the most prevalent bacterial species. At s1, endotoxins were detected in 100% of the root canals (median = 32.43 EU/mL). In parallel, substantial amounts of IL-1β and TNF-α were produced by endodontic content-stimulated macrophages. At s2, a significant reduction in endotoxin levels was observed in all groups, with GI presenting the greatest reduction (P < .05). After a root canal rinse with EDTA (s3), intracanal medication (s4), and before root canal obturation (s5), endotoxin levels reduced without differences between groups (P < .05). IL-1β and TNF-α release decreased proportionally to the levels of residual endotoxin (P < .05). Regardless of the use of sodium hypochlorite or CHX, the greatest endotoxin reduction occurs after chemomechanical preparation. Increasing steps of root canal therapy associated with intracanal medication enhances endotoxin reduction, leading to a progressively lower activation of proinflammatory cells such as macrophages.

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Dental roots that have been exposed to the oral cavity and periodontal pocket environment present superficial changes, which can prevent connective tissue reattachment. Demineralizing agents have been used as an adjunct to the periodontal treatment aiming at restoring the biocompatibility of roots. OBJECTIVE: This study compared four commonly used demineralizing agents for their capacity of removing smear layer and opening dentin tubules. METHODS: Fifty fragments of human dental roots previously exposed to periodontal disease were scaled and randomly divided into the following groups of treatment: 1) CA: demineralization with citric acid for 3 min; 2) TC-HCl: demineralization with tetracycline-HCl for 3 min; 3) EDTA: demineralization with EDTA for 3 min; 4) PA: demineralization with 37% phosphoric acid for 3 min; 5) Control: rubbing of saline solution for 3 min. Scanning electron microscopy was used to check for the presence of residual smear layer and for measuring the number and area of exposed dentin tubules. RESULTS: Smear layer was present in 100% of the specimens from the groups PA and control; in 80% from EDTA group; in 33.3% from TC-HCl group and 0% from CA group. The mean numbers of exposed dentin tubules in a standardized area were: TC-HCl=43.8±25.2; CA=39.3±37; PA=12.1±16.3; EDTA=4.4±7.5 and Control=2.3±5.7. The comparison showed significant differences between the following pairs of groups: TC-HCl and Control; TC-HCl and EDTA; CA and Control; and CA and EDTA. The mean percentages of area occupied by exposed dentin tubules were: CA=0.12±0.17%; TC-HCl=0.08±0.06%; PA=0.03±0.05%; EDTA=0.01±0.01% and Control=0±0%. The CA group differed significantly from the others except for the TC-HCl group. CONCLUSION: There was a decreasing ability for smear layer removal and dentin tubule widening as follows: AC>TC-HCl>PA>EDTA. This information can be of value as an extra parameter for choosing one of them for root conditioning.

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This study was evaluated the response of subcutaneous connective tissue of isogenic mice to calcium hydroxide-based pastes with chlorhexidine digluconate (CHX). Seventy isogenic male BALB/c mice aged 6-8 weeks and weighing 15-20 g were randomly assigned to 8 groups. The animals received polyethylene tube implants as follows: Groups I, II, and III (n=10) - Calen® paste mixed with 0.4% CHX (experimental paste; Calen/CHX) for 7, 21, and 63 days, respectively; Groups IV, V, and VI (n=10) - UltraCal™ paste mixed with 2% CHX (experimental paste supplied by Ultradent Products Inc.; Ultracal/CHX) for 7, 21, and 63 days, respectively; and Groups VII and VIII (n=5): empty tube for 7 and 21 days, respectively. At the end of the experimental periods, the implants were removed together with the surrounding tissues (skin and subcutaneous connective tissue). The biopsied tissues were subjected to routine processing for histological analysis. Using a descriptive analysis and a four-point (0-3) scoring system, the following criteria were considered for qualitative and quantitative analysis of the tissue around the implanted materials: collagen fiber formation, tissue thickness and inflammatory infiltrate. A quantitative analysis was performed by measuring the thickness (µm), area (µm²) and perimeter (µm) of the reactionary granulomatous tissue formed at the tube ends. Data were analyzed statistically by the Kruskal-Wallis test and Dunn's post-test (α=0.05). Calen/CHX showed biocompatibility with the subcutaneous and reactionary tissues, with areas of discrete fibrosis and normal conjunctive fibrous tissue, though without statistically significant difference (p>0.05) from the control groups. In Groups I to III, there was a predominance of score 1, while in Groups IV to VI scores 2 and 3 predominated for all analyzed parameters. UltraCal/CHX, on the other hand, induced the formation of an inflammatory infiltrate and abundant exudate, suggesting a persistent residual aggression from the material, even 63 days after implant placement. In conclusion, the Calen paste mixed with 0.4% CHX allowed an adequate tissue response, whereas the UltraCal paste mixed with 2% CHX showed unsatisfactory results.

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This article reports the case of a 55-year-old female patient who presented with unsatisfactory temporary crowns in the right mandibular premolars and molars, and a premolar-to-molar fixed partial denture in the left side. The clinical and radiographic examinations revealed a fracture of the left first premolar that was a retainer of the fixed partial denture and required extraction. Initially, the acrylic resin crowns were replaced by new ones, and a provisional RPD was made using acrylic resin and orthodontic wire clasps to resolve the problem arising from the loss of the fixed partial denture. Considering the patient's high esthetic demands, the treatment options for the definitive prosthetic treatment were discussed with her and rehabilitation with implant-supported dentures was proposed because the clinical conditions of the residual alveolar ridge were suitable for implant installation, and the patient's general health was excellent. However, the patient did not agree because she knew of a failed case of implant-retained denture in a diabetic individual and was concerned. The patient was fully informed that implant installation was the best indication for her case, but the arguments were not sufficient to change her decision. The treatment possibilities were presented and the patient opted for a clasp-retained removable partial denture (RPD) associated with the placement of crowns in the pillar teeth. The temporary RPD was replaced by the definitive RPD constructed subsequently. Although RPD was not the first choice, satisfactory esthetic and functional outcomes were achieved, overcaming the patient's expectations. This case report illustrates that the dentist must be prepared to deal with situations where, for reasons that cannot be managed, the patient does not accept the treatment considered as the most indicated for his/her case. Alternatives must be proposed and the functional and esthetic requirements must be fulfilled in the best possible manner.

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PURPOSE: This study evaluated the inflammatory reaction caused by the implantation of iodoform and calcium hydroxide in the back of rats. These drugs may be used as intracanal dressings to eliminate residual bacteria of the root canal system. METHODS: Twenty albinic rats (Rattus norvegicus, var Wistar) were divided into four groups: control group 1 (CG1) had normal skin; control group 2 (CG2) had wounded tissue without drugs; in groups 3 and 4, iodoform (IG) and calcium hydroxide (CHG) were inserted into the wounds, respectively. After 3, 5 and 11 days, slices of the implanted areas were macroscopically and microscopically observed regarding to their qualitative and quantitative aspects. RESULTS: In the macroscopical analysis, the CHG showed a large area of necrosis and swelling, which progressively decreased; in the IG the presence of iodoform surrounded by normal tissue was observed. The qualitative and quantitative histological analysis showed that IG promoted a shorter delay in the inflammatory response than the CHG. CONCLUSION: The inflammatory reaction for iodoform had a peak period five days after the drug insertion. By comparison, calcium hydroxide showed a very large area of necrosis that could only be partially eliminated after eleven days.

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Accelerated stability tests are indicated to assess, within a short time, the degree of chemical degradation that may affect an active substance, either alone or in a formula, under normal storage conditions. This method is based on increased stress conditions to accelerate the rate of chemical degradation. Based on the equation of the straight line obtained as a function of the reaction order (at 50 and 70 ºC) and using Arrhenius equation, the speed of the reaction was calculated for the temperature of 20 ºC (normal storage conditions). This model of accelerated stability test makes it possible to predict the chemical stability of any active substance at any given moment, as long as the method to quantify the chemical substance is available. As an example of the applicability of Arrhenius equation in accelerated stability tests, a 2.5% sodium hypochlorite solution was analyzed due to its chemical instability. Iodometric titration was used to quantify free residual chlorine in the solutions. Based on data obtained keeping this solution at 50 and 70 ºC, using Arrhenius equation and considering 2.0% of free residual chlorine as the minimum acceptable threshold, the shelf-life was equal to 166 days at 20 ºC. This model, however, makes it possible to calculate shelf-life at any other given temperature.

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Estudaram-se o efeito do transporte e a mudança de local de manejo sobre a produção e a composição do leite e sobre as variáveis fisiológicas, utilizando-se 12 cabras da raça Alpina em final de lactação. Semanalmente, foram mensuradas a produção e composição do leite e a contagem de células somáticas, além do volume do leite residual após administração de ocitocina. Foram colhidas amostras de sangue para dosagem hormonal (cortisol) e enzimática (glicose) no plasma no dia do transporte: antes (7h10min) e após (8h20min, 8h30min e 10h30min) o transporte. Nas três semanas subsequentes ao transporte, também foram colhidas amostras de sangue às 8h20min. Obtiveram-se teores mais elevados (P<0,05) de cortisol e glicose após o transporte e a mudança de local de manejo, e menor produção de leite (P<0,05) um dia após o evento. Porcentagem de gordura (P<0,05) e contagem de células somáticas apresentaram diferenças significativas (P<0,05) após o transporte. Os resultados permitem concluir que o transporte é um agente estressor que pode, momentaneamente, influenciar a produção animal.

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Foram estudadas as propriedades térmicas e mecânicas de compósitos de polipropileno, virgem e reciclado, reforçados com 30% em massa de fibras residuais de sisal, assim como o perfil de processamento e a morfologia da matriz polimérica. Para tanto, foram determinadas a resistência à tração, o módulo de Young, alongamento na ruptura, e energia de impacto. As amostras também foram caracterizadas por MEV, DMTA e TG. Para ambos os compósitos de polipropileno, virgem e reciclado, com a adição das fibras, o alongamento na ruptura mostrou uma queda significativa, enquanto que a resistência à tração não sofreu grandes variações. Houve um aumento significativo nos valores de tração na ruptura e de energia de impacto com a adição das fibras de sisal na matriz de polipropileno. As análises térmicas mostraram ligações secundárias, como as ligações polares, entre as fibras e a matriz, concordando com o comportamento mecânico dos compósitos. Constatou-se que a temperatura de transição vítrea não variou após a adição da fibra.

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OBJETIVO: Comparar a fala e o funcionamento velofaríngeo após as técnicas de retalho faríngeo e veloplastia intravelar para a correção da disfunção velofaríngea residual. MÉTODOS: Foi realizado um estudo retrospectivo com análise de 148 casos com fissura labiopalatina operada e submetidos à correção cirúrgica da disfunção velofaríngea, sendo 77 com retalho faríngeo (média de idade: 20,4 anos) e 71 com veloplastia intravelar (média de idade: 16,2 anos). Foram avaliadas a ressonância da fala, a presença de articulações compensatórias, a emissão de ar nasal e a extensão da falha no fechamento velofaríngeo antes e após as duas técnicas. RESULTADOS: Dos 77 casos submetidos ao retalho faríngeo 64 (83%) apresentaram melhora na ressonância, enquanto que dos 71 casos com veloplastia intravelar 48 (68%) revelaram melhora, havendo diferença significativa entre os grupos. No grupo com retalho faríngeo, seis (8%) apresentaram melhora na articulação compensatória e dois (3%) no grupo veloplastia intravelar, enquanto a emissão de ar nasal melhorou em 17 (22%) casos com retalho faríngeo e em 18 (26%) com veloplastia intravelar. Não houve diferença entre os grupos quanto à articulação compensatória e emissão de ar nasal. A falha no fechamento velofaríngeo reduziu em 75 (96%) casos com retalho faríngeo e 46 (66%) com a veloplastia intravelar, havendo diferença entre os grupos. CONCLUSÃO: A técnica de retalho faríngeo mostrou-se mais efetiva na melhora da ressonância e no fechamento velofaríngeo quando comparada à veloplastia intravelar.

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Este artigo discute um modelo de previsão combinada para a realização de prognósticos climáticos na escala sazonal. Nele, previsões pontuais de modelos estocásticos são agregadas para obter as melhores projeções no tempo. Utilizam-se modelos estocásticos autoregressivos integrados a médias móveis, de suavização exponencial e previsões por análise de correlações canônicas. O controle de qualidade das previsões é feito através da análise dos resíduos e da avaliação do percentual de redução da variância não-explicada da modelagem combinada em relação às previsões dos modelos individuais. Exemplos da aplicação desses conceitos em modelos desenvolvidos no Instituto Nacional de Meteorologia (INMET) mostram bons resultados e ilustram que as previsões do modelo combinado, superam na maior parte dos casos a de cada modelo componente, quando comparadas aos dados observados.

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Este trabalho faz uma análise das estimativas de teores de umidade obtidas com o método Ground Penetrating Radar (GPR) comparativamente às determinadas com os métodos Time Domain Reflectometry (TDR) e gravimétrico. Os dados foram obtidos em dois experimentos diferentes: um experimento controlado em laboratório buscando reproduzir um meio homogêneo onde foram obtidas as medidas de umidade com GPR (antenas de 1 GHz) e TDR, e outro experimento de campo onde foram obtidos dados com GPR (antenas de 200 MHz) e de amostras de solos do local. Para a obtenção das estimativas a partir do método GPR foram analisados os eventos relativos à onda de transmissão direta entre as antenas, onda refratada criticamente e onda refletida em interfaces com diferentes propriedades elétricas.O GPR mostrou-se sensível às variações de umidades presentes nos dois experimentos e apresentou boa correlação com os dados obtidos com TDR (REQM de0,007 m³m-3) e das amostras (REQM de 0,039 m³m-3).