Raman spectra soft modeling of the biodiesel oxidation through evolving factor analysis & multivariate curve resolution.

The oxidative stability of biodiesel is defined by its relative resistance to the action of oxygen at room temperature. Its determination is an essential reference to the quality of biofuel and a significant parameter to be determined. This parameter concerns the quality of the biodiesel to be supplied to the consumer, and its determination is fundamental to maintaining the engine's proper functioning. Raman spectroscopy allows the rapid obtaining of structural information regarding biodiesel quality and, when aided by multivariate analysis methods, allows a quantitative determination of specific properties. This work uses Raman spectroscopy, Multivariate Curve Resolution with Alternative Least Squares (MCR-ALS) method, and Evolving Factor Analysis (EFA) to study biodiesel's oxidation kinetics. Also, the vibrational modes C = C, CH2, and CH3 were identified as the main structural groups involved in this process, corroborating previous studies. The MCR-ALS & EFA combination allowed modeling of the degradation kinetics following an A â†’ B â†’ C mechanism, where A corresponds to the biodiesel (starting material), B is related to the hydroperoxide mixture, and C is the final product. The results also suggested that this process follows a first-order reaction, with kinetic constant values of k1 = 0.0056 min-1 and k2 = 0.0031 min-1.

Paediatric dentists' stress during dental care for children under sedation: a cross-sectional study.

PURPOSE: The knowledge of the stress related to the practice of paediatric dentistry is scarce. The aim of this study was to verify the stress perceived by paediatric dentists related to young children's dental treatment under sedation and their association with child's behaviour and other independent variables. METHODS: A cross-sectional repeated measures study was performed with four paediatric dentists who treated 81 sedated preschoolers. Paediatric dentists reported their stress at the end of the session using the visual analog scale (VAS 0-100 mm). Samples of saliva were collected to measure the dentists' salivary cortisol level throughout the dental session. The sessions of dental treatment were video recorded for evaluation of the child's behaviour. Children's behaviour was assessed using the Ohio State University Behavioral Rating Scale (OSUBRS). The association between the VAS scores and the other variables was verified using bivariate tests and generalised estimating equation (alpha 0.05). RESULTS: Paediatric dentists felt slightly stressed in most of the sessions (VAS median 7 points; minimum 0, maximum 97 points). VAS associated with the struggling behaviour of the child (B 0.53; 95%CI 0.32-0.74; p ≤ 0.001) and the time since dentist's graduation (B - 1.41, 95% CI - 1.87 to - 0.94; p ≤ 0.001) but not with dentist's salivary cortisol (rho - 0.053, p = 0.639). CONCLUSION: The more frequent the child's struggling behaviour during dental treatment and the shorter the time elapsed since the professional's graduation, the higher the level of objectively and subjectively measured stress of the paediatric dentist during the dental procedure.

SOX2 and BCL-2 Expressions in Odontogenic Keratocyst and Ameloblastoma.

BACKGROUND: The purpose of this experimental study was to compare the immunohistochemical expression of SOX2 and BCL-2 in Odontogenic Keratocyst (OKC) and Ameloblastoma (AB) specimens, and to identify a possible correlation in their expression. MATERIAL AND METHODS: Immunohistochemical analysis was performed to evaluate SOX2 and BCL-2 expression in OKC (n = 20) and AB (n = 20). The immunoexpression was analyzed by a quantitative and qualitative scoring system. The comparison between the immunoexpression of SOX 2 and BCL-2 was assessed by the Mann-Whitney U-test. Spearman's correlation coefficient evaluated the correlation between SOX2 and BCL-2 expressions. RESULTS: SOX2 and BCL-2 expression was observed in all specimens of OKC in the full thickness of the epithelium lining. SOX2 immunostaining was higher in OKC, in comparison with AB samples (P<0.05). BCL-2 immunostaining between OKC and AB was not statistically significant. There was no significant correlation between SOX2 and BCL-2 in OKC and AB specimens. CONCLUSIONS: SOX2 and BCL-2 expressions in OKC may suggest their relationship with the biological behavior of this lesion, and the higher expression of SOX2 might be an upstream influence on the Hh signaling pathway.

Custom-made transcriptional biosensors for metabolic engineering.

Transcriptional biosensors allow screening, selection, or dynamic regulation of metabolic pathways, and are, therefore, an enabling technology for faster prototyping of metabolic engineering and sustainable chemistry. Recent advances have been made, allowing for routine use of heterologous transcription factors, and new strategies such as chimeric protein design allow engineers to tap into the reservoir of metabolite-binding proteins. However, extending the sensing scope of biosensors is only the first step, and computational models can help in fine-tuning properties of biosensors for custom-made behavior. Moreover, metabolic engineering is bound to benefit from advances in cell-free expression systems, either for faster prototyping of biosensors or for whole-pathway optimization, making it both a means and an end in biosensor design.

Application of bioelectrical impedance analysis in prediction of light kid carcass and muscle chemical composition.

Carcass data were collected from 24 kids (average live weight of 12.5±5.5 kg; range 4.5 to 22.4 kg) of Jarmelista Portuguese native breed, to evaluate bioelectrical impedance analysis (BIA) as a technique for prediction of light kid carcass and muscle chemical composition. Resistance (Rs, Ω) and reactance (Xc, Ω), were measured in the cold carcasses with a single frequency bioelectrical impedance analyzer and, together with impedance (Z, Ω), two electrical volume measurements (VolA and VolB, cm2/Ω), carcass cold weight (CCW), carcass compactness and several carcass linear measurements were fitted as independent variables to predict carcass composition by stepwise regression analysis. The amount of variation explained by VolA and VolB only reached a significant level (P<0.01 and P<0.05, respectively) for muscle weight, moisture, protein and fat-free soft tissue content, even so with low accuracy, with VolA providing the best results (0.326⩽R 2⩽0.366). Quite differently, individual BIA parameters (Rs, Xc and Z) explained a very large amount of variation in dissectible carcass fat weight (0.814⩽R 2⩽0.862; P<0.01). These individual BIA parameters also explained a large amount of variation in subcutaneous and intermuscular fat weights (respectively 0.749⩽R 2⩽0.793 and 0.718⩽R 2⩽0.760; P<0.01), and in muscle chemical fat weight (0.663⩽R 2⩽0.684; P<0.01). Still significant but much lower was the variation in muscle, moisture, protein and fat-free soft tissue weights (0.344⩽R 2⩽0.393; P<0.01) explained by BIA parameters. Still, the best models for estimation of muscle, moisture, protein and fat-free soft tissue weights included Rs in addition to CCW, and accounted for 97.1% to 99.8% (P<0.01) of the variation observed, with CCW by itself accounting for 97.0% to 99.6% (P<0.01) of that variation. Resistance was the only independent variable selected for the best model predicting subcutaneous fat weight. It was also selected for the best models predicting carcass fat weight (combined with carcass length, CL; R 2=0.943; P<0.01) and intermuscular fat weight (combined with CCW; R 2=0.945; P<0.01). The best model predicting muscle chemical fat weight combined CCW and Z, explaining 85.6% (P<0.01) of the variation observed. These results indicate BIA as a useful tool for prediction of light kids' carcass composition.

Produção de biomassa aérea, teor e rendimento de extrato das folhas de crajiru [ Arrabidaea chica (Bonpl. ) B. Verl. ] em função de adubação orgânica em Manaus, estado do Amazonas, Brasil / Aerial biomass production, content and yield of crajiru leaf extract [Arrabidaea chica (Bonpl. ) B. Verl. ] as a function of organic fertilizer in Manaus, state of Amazonas, Brazil

RESUMO A espécie Arrabidaea chica pertencente à família Bignoniaceae é também conhecida popularmente como crajiru. É Utilizada tradicionalmente no tratamento de enfermidades da pele, inflamações, infecções, dentre outros. O objetivo deste trabalho foi avaliar a produção de biomassa aérea, teor e rendimento de extrato de crajiru em função de diferentes fontes de adubo orgânico em Manaus, AM. As mudas foram formadas através de estacas e mantidas por 60 dias em casa de vegetação. O experimento foi conduzido em esquema fatorial 5x3 com delineamento em blocos casualizados onde os níveis dos fatores foram as diferentes fontes de adubo orgânico: composto (5,0 kg/m2), esterco de aves (3,0 kg/m2), casca de guaraná (4,0 kg/m2), esterco de gado (4,0 kg/m2) e controle (ausência), e os três morfotipos de crajiru. Obedeceu-se o espaçamento de 1,0x1,0 m entre planta e 2,0 m entre blocos. Após 240 dias foram avaliadas a produção de folhas e caules, relação folha/caule, teor de extratos hexânico concentrado em evaporador rotativo obtido pela fórmula: (massa do extrato/massa da amostra total)x100; e o rendimento de extrato estimado pela equação: (%extrato x massa seca total das folhas)/100. Os dados foram submetidos à análise de variância e as médias ao Teste de Tukey (p<0,05). As fontes de adubo orgânico promoveram melhor desenvolvimento das plantas de, exceto para o morfotipo 1. O esterco de aves proporcionou maior produção de biomassa, teor e rendimento de extratos. Dessa forma, sugere-se que a adubação orgânica propicia maior produção de biomassa, teor e rendimento de extratos de A. chica.

ABSTRACT The Arrabidaea chicaspecies belongs to the Bignoniaceae family and is also popularly known as crajiru. It is traditionally used to treat skin diseases, inflammations and infections. The objective of this study was to evaluate the biomass production, the content and the yield of crajiru extract in face of different sources of organic fertilizer in Manaus, AM. The seedlings were formed by cuttings and kept for 60 days in a greenhouse. The trial was conducted in a 5x3 factorial design with randomized block organization where the factor levels were different sources of organic fertilizer: compound (5.0 kg / m 2), chicken manure (3.0 kg / m 2), bark guarana (4.0 kg / m2), cattle manure (4.0 kg / m 2) and control (absence), and the three morphotypes of crajiru. It was obeyed the spacing between the plants (1,0 x1,0m) and the blocks (2,0m) . After 240 days it were evaluated the production of leaves and stems, the leaf / stem ratio, and the content of hexane extracts concentrated by rotary evaporation obtained by the following formula: (mass of extract / mass of total sample) x100; and the yield estimated by the equation extract: (% extract x total dry mass of leaves) / 100. The data were subjected to analysis of variance and means to the Tukey"s test (p <0.05). The sources of organic fertilizer promoted better development of plants, except for the morphotype 1. The poultry manure provided higher biomass, content and yield of extracts. Thus, it is suggested that the organic fertilizer provides greater biomass production, content and yield of A. chica extracts.

Propagação vegetativa de estacas de Piper hispidumSw. em diferentes substratos / Vegetative propagation of cuttings of Piper hispidum Sw. in different substrates

RESUMO Piper hispidum é uma espécie pioneira pertencente à família Piperaceae, com importância na medicina popular e na obtenção de óleo essencial. Assim como outras espécies da família, possui poucas informações sobre técnicas de cultivo. O objetivo foi avaliar a propagação via estaquia de Piper hispidum em função do tipo de substrato e estaca em Manaus, Amazonas, Brasil. O experimento foi realizado na Embrapa Amazônia Ocidental. O delineamento utilizado foi inteiramente casualizado em esquema fatorial 3 (estacas) x 5 (substratos), com três repetições de 12 estacas, sendo as estacas (apical, mediana e basal) e os substratos (areia lavada, substrato comercial, solo + esterco de aves, solo + casca de guaraná e fibra de coco). Foram avaliadas: enraizamento (%), número de brotações, comprimento da maior brotação (cm), número de folhas, comprimento da maior raiz (cm), massa seca da raiz (g) e massa seca das brotações (g). Foi realizada análise de variância pelo teste F a 5% de probabilidade e para as médias foi realizado o teste Tukey ao nível de 5% de probabilidade. Recomenda-se utilizar estacas apicais e basais, nesta ordem. Ocorreu interação entre os fatores substrato e tipos de estaca somente para variável número de brotações. Os substratos areia lavada e substrato comercial são indicados para maiores porcentagens de enraizamento com 81,56% e 81,33%, respectivamente. O enraizamento foi superior nas estacas apicais (85,67%) e basais (74,47%). Porém, para esta espécie os substratos solo + esterco de aves e/ou solo + casca de guaraná foram mais indicados quando o objetivo é obter estacas de qualidade.

ABSTRACT Piper hispidum is a pioneer species belonging to the family Piperaceae, with relevance in popular medicine and in obtaining essential oil. As other species of this family, there is little information about cultivation techniques. The aim of this work was to evaluate the propagation through cutting from the Piper hispidum according to the type of substrate and cutting technique in Manaus, Amazonas, Brazil. The trial experiment was conducted at the Embrapa Western Amazon. The design was completely randomized factorial 3 x 5, with three replications of 12 cuttings with types of cuttings (apical, median and basal) and substrates (washed sand, commercial substrate, soil + poultry manure, soil + guarana shell and coconut fiber). After 60 days, the following characteristics were evaluated: rooting (%), number of shoots, length of the largest sprouting (cm), number of leaves, length of the longest root (cm), root dry weight (g) and dry weight of shoots (g). An analysis of variance was performed by the F test at 5% probability and for the averages` comparison the Tukey test was done at 5% level of probability. It is recommended to employ apical and basal cuttings, respectively. There was interaction between the factors and substrate types of cuttings only for the variable number of sprouts. These two substrates, washed sand and commercial substrate, are suggested for higher percentages of rooting with 81,56% and 81,33 %, respectively. The rooting was higher in the apical cuttings (85,67 %) and basal ones (74,47 % ). However, for this species, the substrates soil + poultry manure and/or soil + guaraná shell were most indicated when the goal was to obtain high-quality cuttings.

Leishmania chagasi naturally resistant to nitric oxide isolated from humans and dogs with visceral leishmaniasis in Brazil.

Nitric oxide (NO) plays an important role as a leishmanicidal agent in murine macrophages. NO resistant Escherichia coli and Mycobacterium tuberculosis have been associated with poor outcomes of their resulting diseases. NO resistant Leishmania braziliensis has also been identified and exacerbates the clinical course of human leishmaniasis. We report, for the first time, natural resistance of Leishmania chagasi promastigotes to NO. These parasites were isolated from humans and dogs with visceral leishmaniasis. We also demonstrate that this resistance profile was associated with a greater survival capacity and a greater parasite burden in murine macrophages, independent of activation and after activation by IFN-γ and LPS.

Characterization of inflammatory cell infiltrate in human dental pulpitis.

INTRODUCTION: To evaluate the microscopic characteristics and densities (per mm(2) ) of tryptase(+) mast cells, CD4(+) T helper lymphocytes, CD45RO(+) memory T lymphocytes, foxp3(+) T regulatory lymphocytes, CD20(+) B lymphocytes, CD68(+) macrophages, and CD31(+) blood vessels in human dental pulpitis (n=38) and healthy pulpal tissue (n=6). METHODOLOGY: The pulps of 38 human teeth with a clinical diagnosis of irreversible pulpitis were removed by pulpectomy. The pulp tissue was immersed in 10% buffered formalin for evaluation using light microscopy. Tryptase, CD4, CD45RO, foxp3, CD20, CD68, and CD31 expressions were analysed using immunohistochemistry; other microscopic features, such as intensity of inflammatory infiltrate and collagen deposition, were evaluated using haematoxylin and eosin stain. Wilcoxon and Mann-Whitney tests were used for statistical analysis. The significance level was set at α=5%. RESULTS: Two microscopic patterns of pulpitis were found: group 1 (G1) (n=15) had an intense inflammatory infiltrate and mild collagen deposition; conversely, group 2 (G2) (n=23) had a scarce inflammatory infiltrate and intense collagen deposition. The numbers of CD68(+) macrophages (P=0.004) and CD20(+) B (P=0.068) lymphocytes and the density of blood vessels (P=0.002) were higher in G1 than in G2. However, a similar number of CD4(+) and CD45RO(+) T lymphocytes was found in both groups (P>0.05). When present, tryptase(+) mast cells were equally distributed in G1 and G2, whereas foxp3(+) T regulatory lymphocytes were detected in 59% and 14% of the samples of G1 and G2. Controls exhibited lower numbers of foxp3, tryptase, CD4, CD45RO, CD68 and CD20 positive cells than G1 and G2. CONCLUSIONS: Irreversible pulpitis had distinct microscopic features with important quantitative and qualitative differences in inflammatory cell infiltration.

Differential infiltration of CD8+ and NK cells in lip and oral cavity squamous cell carcinoma.

BACKGROUND: CD8+ and natural killer (NK) cells have been considered the most effective cells in the combat of cancer, contributing to better prognosis and longer survival. METHODS: The aim of this study was to evaluate the population of CD8+ and NK cells, by immunohistochemistry, in samples of oral cavity squamous cell carcinoma (OCSCC) and lip squamous cell carcinoma (LSCC), leukoplakia, actinic cheilitis, and healthy oral mucosa (control). The relationship of CD8+ and NK cells with survival data, lymph node metastasis, tumor size, and proliferative index was also evaluated. RESULTS: The number of peritumoral and intratumoral CD8+ and NK cells was significantly higher in LSCC, when compared with control, pre-malignant lesions, and OCSCC. A higher proportion of peritumoral CD8+ cells demonstrated correlation with a lower neoplastic proliferative index. Moreover, patients with OCSCC with a high density of peritumoral CD8+ cells showed a tendency towards a longer survival time. CONCLUSIONS: The differential CD8+ and NK cells infiltration in oral SCC might reflect a distinctive tumor microenvironment with a favorable local cytotoxic immune response against neoplastic cells.

Immunohistochemical approach reveals involvement of inducible nitric oxide synthase in rat late development.

To better understand the role of nitric oxide (NO) in mammal development, specifically in the transition of the fetal stages at birth, we studied the timing of cell-specific expression of inducible NO synthase (iNOS) isoform during gestational periods of rats, mainly at the late stages of intra-uterine development. Before experimentation, the samples were collected (from 17th to 21st gestational days), fixed in 10% buffered formalin and embedded in paraffin for histological procedures. Hereafter, the sections (5 mum thickness) obtained from different embryos were immunostained by avidin-biotin-immunoperoxidase technique, by using antibody against iNOS isoform. The most of cell immunopositive was suggestive of granulocyte-like cells and those cells were resident close to the blood vessels in different organs, such as: lung, liver or bone marrow environment. Sometimes we noted immunopositive cells in the blood flow, as reported in the thymus. In agreement, iNOS expression, obtained by western blotting analysis, showed the same profile. Together, our data shows that iNOS expression increased gradually during the late stages of rat development (from E17 to E21) and it was executed by cells close to blood vessels. Thus, we can clearly to predict that this expression was finely modulated and it contributes for time-line dependent NO production during rat late development.

Alloxan-induced diabetes delays repair in a rat model of closed tibial fracture.

A closed fracture was performed on the left tibia of 3-month-old Wistar rats weighing 250 to 350 g that were either healthy (N = 24) or made diabetic with alloxan (N = 24) to investigate the effect of alloxan-induced diabetes on the course of bone fracture healing. Histomorphometric analysis of the fracture site was performed at 7, 14, 25, and 35 days. After 7 days, diabetic rats had significantly less cartilage (P = 0.045) and greater fibrous connective (P = 0.006) tissue formation at the fracture site compared to controls. In contrast, marked callus formation was seen in diabetic rats with significant osteogenesis (P = 0.011, P = 0.010, P = 0.010, respectively, for 14, 25, and 35 days) and chondrogenesis (P = 0.028, P = 0.033, P = 0.019) compared to controls. Radiographic analysis revealed a displaced fracture with poor bone fragment alignment and delayed consolidation at these times in the diabetic group. The levels of alkaline phosphatase were significantly higher in diabetic rats at 25 days (P = 0.009). These results suggest that the initial excessive formation of fibrous connective tissue associated with delay in chondrogenesis and osteogenesis may not provide suitable stability of the fractured site, contributing to the inappropriate alignment of fragments and an increase in the volume of callus in later stages of repair. The resulting displaced fracture in diabetic rats requires long periods for remodeling and complete bone consolidation.

Alloxan-induced diabetes delays repair in a rat model of closed tibial fracture

A closed fracture was performed on the left tibia of 3-month-old Wistar rats weighing 250 to 350 g that were either healthy (N = 24) or made diabetic with alloxan (N = 24) to investigate the effect of alloxan-induced diabetes on the course of bone fracture healing. Histomorphometric analysis of the fracture site was performed at 7, 14, 25, and 35 days. After 7 days, diabetic rats had significantly less cartilage (P = 0.045) and greater fibrous connective (P = 0.006) tissue formation at the fracture site compared to controls. In contrast, marked callus formation was seen in diabetic rats with significant osteogenesis (P = 0.011, P = 0.010, P = 0.010, respectively, for 14, 25, and 35 days) and chondrogenesis (P = 0.028, P = 0.033, P = 0.019) compared to controls. Radiographic analysis revealed a displaced fracture with poor bone fragment alignment and delayed consolidation at these times in the diabetic group. The levels of alkaline phosphatase were significantly higher in diabetic rats at 25 days (P = 0.009). These results suggest that the initial excessive formation of fibrous connective tissue associated with delay in chondrogenesis and osteogenesis may not provide suitable stability of the fractured site, contributing to the inappropriate alignment of fragments and an increase in the volume of callus in later stages of repair. The resulting displaced fracture in diabetic rats requires long periods for remodeling and complete bone consolidation.

Unicystic ameloblastoma in a child: a differential diagnosis from the dentigerous cyst and the inflammatory follicular cyst.

Unicystic ameloblastoma (UA) is a benign epithelial odontogenic tumor of the jaws with an aggressive potential that commonly occurs in children. This cystic odontogenic neoplasm is generally asymptomatic and found during routine radiographs. The purposes of this report were to describe a case of UA involving the crown of the unerupted right mandibular second premolar in an 11-year-old girl under orthodontic treatment, and discuss its diagnosis and radiographic and microscopic findings, emphasizing its distinction from the dentigerous cyst and the inflammatory follicular cyst.

Impactos do fogo sobre serpentes (Squamata) no Parque Nacional de Ilha Grande (PR/MS), Brasil / The impact of fire upon squamata snakes in the Ilha Grande National Park in the states of Paraná and Mato Grosso do Sul, Brazil / Implactos del fuego sobre serpientes (squamata) en el parque nacional de ilha grande (PR/MS), Brasil

Incêndios são ocorrências periódicas no Parque Nacional de Ilha Grande, e o fogo é um dos principais fatores de ameaça à sobrevivência da herpetofauna nessa unidade de conservação. Esse trabalho teve como objetivos descrever as reações das serpentes frente ao fogo, identificar as espécies atingidas pelos incêndios e correlacionar a natureza das lesões causadas pelo fogo. As atitudes das serpentes frente ao fogo foram determinadas pela descrição das reações comportamentais apresentadas pelos indivíduos avistados durante os incêndios. A determinação da causa da morte e das lesões foi realizada pela avaliação física e necroscópica dos animais feridos e mortos encontrados em áreas queimadas. As coletas foram realizadas em setembro de 2003, em pontos aleatórios, durante e imediatamente após os incêndios. Foram avistadas frente ao fogo, uma Bothrops moojeni, uma Philodryas patagoniensis e um colubrídeo não-identificado. Uma Micrurus lemniscatus foi encontrada viva apresentando queimaduras profundas e deficiência visual em decorrência das lesões térmicas. Foram coletados cadáveres de quatro B. moojeni, de um colubrídeo não-identificado, e de uma Tamnodynastes hypoconia. As B. moojeni e o colubrídeo não-identificado se encontravam carbonizados, enquanto a T. hypoconia apresentava sinais de afecção respiratória. Vestígios indicaram que os cadáveres das serpentes são uma importante fonte de recurso alimentar nos períodos pós-fogo. Incêndios de elevada intensidade e grandes extensões atingem diretamente serpentes no Parque, inclusive espécies de grande porte como a Bothrops moojeni. A morte de indivíduos pela ação do fogo pode contribuir para o declínio das espécies em longo prazo no Parque Nacional de Ilha Grande.

There are periodic occurrences of in the Ilha Grande National Park (South of Brazil), and it is one of the main menacing factors to the Herpetofauna survival in that conservation unit. The objectives of this study were to describe the snakes’reactions to fire, to identify the species affected by fires, and to correlate the nature of the lesions produced by fire. The reactions of the snakes toward fire were determined by the description of the behavior presented by the individuals observed during wildfires. The determination of mortality causes and correlated lesions were accomplished by physical and necroscopic evaluation of wounded and dead animals found in burned areas. The collections were accomplished in randomized points in September 2003, during - and immediately - after fire occurrences. Three snakes were observed during wildfires, one Bothrops moojeni, one Philodryas patagoniensis, and one non-identified colubrid. A Micrurus lemniscatus was found alive, presenting deep burns and visual deficiency due to thermal lesions. The corpses of four B. moojeni, one non-identified colubrid, and one Tamnodynastes hypoconia were collected. The four B. moojeni and the non-identified colubrid were carbonized. The T. hypoconia presented signs of respiratory illness. Vestiges indicated that snakes corpses are an important source of food in post-fire periods. Highly intense wildfires which cover large areas directly affect the Ilha Grande National Park snakes, including big species as B. moojeni. Individuals’ death due to fire action can contribute to the snakes species’ declining in the park in a long term basis.

Los incendios son ocurrencias periódicas en el Parque Nacional de Ilha Grande (sur de Brasil), y uno de los principales factores de amenaza a la supervivencia de la herpetofauna en esa unidad de conservación. Los objetivos de este trabajo fueron describir las reacciones de las serpientes al fuego, identificar las especies afectadas por los incendios y correlacionar la naturaleza de las lesiones causada por el fuego. Las actitudes de las serpientes frente al fuego fueron determinadas por la descripción de las reacciones de comportamiento presentadas por los individuos observados durante los incendios. La determinación de la causa muerte y lesiones se efectuó por evaluación física y necroscópica de los animales heridos y muertos encontrados en las áreas quemadas. Las colectas fueron realizadas en puntos aleatorios en septiembre de 2003, durante y inmediatamente después de las ocurrencias. Fueran avistadas frente al fuego, un Bothrops moojeni, un Philodryas patagoniensis y un colúbrido no identificado. Se encontró un Micrurus lemniscatus vivo, presentando quemaduras profundas y deficiencia visual, debido a las lesiones térmicas. Fueron colectados los cadáveres de cuatro Bothrops moojeni, de un colúbrido no identificado, y de un Tamnodynastes hypoconia. Los cuatro B. Moojeni y el colúbrido no identificado estaban carbonizados. El T. hypoconia presentaba signos de enfermedad respiratoria. Vestigios indicaron que los cadáveres son importante fuente de recurso alimenticio en los períodos posfuego. Los incendios de alta intensidad y gran extensión afectan las serpientes directamente en el Parque Nacional de Ilha Grande, incluso animales de talle grande como B. moojeni. La muerte de individuos por acción del fuego puede contribuir para la caída de las especies en el parque, a largo plazo.

Quantification of mast cells in different stages of human periodontal disease.

OBJECTIVE AND METHODS: Among the cells involved in immune and inflammatory responses in periodontal disease, mast cells have been shown to be capable of generating a large number of biologically active substances. The present study was undertaken to identify and quantify the presence of mast cells in different stages of human periodontal disease using histochemical (toluidine blue) and immunohistochemical (tryptase-positive mast cells) techniques. RESULTS: Mast cell densities (cells per mm(2)) were significantly increased in chronic periodontitis/gingivitis lesions compared with clinically healthy gingival tissues (Health) uniquely by immunohistochemical technique. Interestingly, mast cells were distributed specially in close apposition to mononuclear cells. CONCLUSIONS: In human periodontal disease there is an increase in the number of mast cells that may be participating either in the destructive events or in the defense mechanism of periodontal disease via secretion of cytokines, including perpetuation of the Th2 response, and cellular migration and healing processes.

Lichen sclerosus et atrophicus of the oral mucosa.

Lichen sclerosus et atrophicus (LSA) is a chronic, benign, depigmenting disease of the skin and mucous membranes most frequently affecting the female genitalia. Involvement of the oral mucosa without concurrent genital or skin lesions has been reported only occasionally in the literature. In view of the rarity of reported cases, one lesion affecting only the labial mucocutaneous area is presented along with a description of the disease's clinical and histopathological findings.

Nitric oxide synthesis and severity of human periodontal disease.

The expression of the inducible nitric oxide synthase enzyme (iNOS) is a response to an inflammatory stimulus and produces a large amount of nitric oxide (NO), which may act as a cytotoxic molecule against the invading microorganism and may be related to both harmful and beneficial effects to tissues. OBJECTIVE AND MATERIAL AND METHODS: In order to further characterize the presence of NO in human periodontal disease, we undertook a quantitative study of iNOS positive cells in samples of clinically healthy gingival tissues, plaque-induced gingivitis and localized chronic periodontitis using immunohistochemistry. RESULTS: A significant increase in the number of iNOS+ cells mm-2 was found in the samples of the gingivitis and periodontitis compared with those of the control. In all groups most of the polymorphonuclear cells showed intense immunoreactivity for iNOS independent of the disease stage, and the percentage of iNOS+ polymorphonuclear cells increased significantly in periodontal disease when compared with the control. CONCLUSION: Our results indicate that iNOS increases in the presence of periodontal disease. In addition, our findings suggest that polymorphonuclear cells present an additional activation pathway in periodontal disease, expressing significant iNOS and probably representing an important source of NO in human periodontal disease that has not been previously reported.