Porphyromonas Gingivalis, Porphymmonas Endodontalis, Prevotella Intermedia And Prevotella Nigrescens In Endodontic Lesions Detected By Culture And By Pcr

The aim of this study was to investigate the presence of four black-pigmented bacteria, Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia and Prevotella nigrescens, in endodontic infections by culture and polymerase chain reaction (PCR) analyses. Microbial samples were obtained from 50 teeth with untreated necrotic pulps (primary infection) and from 50 teeth with failing endodontic treatment (secondary infection). Microbiological strict anaerobic techniques were used for serial dilution, plating, incubation, and identification. For PCR detection, the samples were analyzed using species-specific primers of 16S rDNA and the downstream intergenic spacer region. Culture and PCR detected the test species in 13/100 and 50/100 of the study teeth, respectively. The organisms were cultured from 11/50 (22%) of primarily infected root canal samples and from 2/50 (4%) of secondary root canal samples. PCR detection identified the target species in 32/50 (64%) and 18/50 (36%) of primary and secondary infections, respectively. P. gingivalis was rarely isolated by culture methods (1%), but was the most frequently identified test species by PCR (38%). Similarly, P. endodontalis was not recovered by culture from any tooth studied, but was detected by PCR in 25% of the sampled teeth. PCR-based identification also showed higher detection rates of P. intermedia (33%) and P. nigrescens (22%) than culture (13%). In conclusion, P. gingivalis, P. endodontalis, P. intermedia, and P. nigrescens were identified more frequently in teeth with necrotic pulp than in teeth with failing endodontic treatment. 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Relação entre diferentes caracteres de plantas jovens de seringueira Correlations and regressions studies among juvenile rubber tree characters

O presente trabalho foi realizado com o objetivo de determinar a existência e as magnitudes de correlações e regressões lineares simples em plântulas jovens de seringueira (Hevea spp.), para melhor condução de seleção nos futuros trabalhos de melhoramento. Foram utilizadas médias de produção de borracha seca por plântulas por corte, através do teste Hamaker-Morris-Mann (P); circunferência do caule (CC); espessura de casca (EC); número de anéis (NA); diâmetro dos vasos (DV); densidade dos vasos laticíleros (D) e distância média entre anéis de vasos consecutivos (DMEAVC) em um viveiro de cruzamento com três anos e meio de idade. Os resultados mostraram, entre outros fatores, que as correlações lineares simples de P com CC, EC, NA, D, DV e DMEAVC foram, respectivamente, r =t 0,61, 0,34, 0,28, 0,29, 0,43 e -0,13. As correlações de CC com EC, NA, D, DV e DMEAVC foram: 0,65, 0,22, 0,37, 0,33 e 0,096 respectivamente. Estudos de regressão linear simples de P com CC, EC, NA, DV, D e DMEAVC sugerem que CC foi o caráter independente mais significativo, contribuindo com 36% da variação em P. Em relação ao vigor, a regressão de CC com os respectivos caracteres sugere que EC foi o único caráter que contribuiu significativamente para a variação de CC com 42%. As altas correlações observadas da produção com circunferência do caule e com espessura de casca evidenciam a possibilidade de obter genótipos jovens de boa capacidade produtiva e grande vigor, através de seleção precoce dessas variáveis.<br>This study was undertaken aiming to determine the existence of linear correlations, based on simple regression studies for a better improvement of young rubber tree (Hevea spp.) breeding and selection. The characters studied were: yield of dry rubber per tapping by Hamaker-Morris-Mann test tapping (P), mean gurth (CC), bark thickness (EC), number of latex vessel rings (NA), diameter of latex vesseis (DV), density of latex vesseis per 5mm within rings (D) and distance between latex vesseis rings (DMEAVC) in a three and haif years old nursery. The results showed that among other characters, the correlation values between P and CC, EC, NA, DV, D, DMEAVC were r = 0.61, 0.34, 0.28, 0.29, 0.43 and -0.13 respectively. The correlation coefficients values between CC and EC, NA, DV, D, DMEAVC were: r = 0.65, 0.22, 0.37, 0.33 and 0.096 respectively. Linear simple regression of P with CC, EC, NA, DV, D and DMEAVC suggested that CC was the only important and significant character accounting for 36% of the variation on P. Concerning with vigor, the regression of CC on the same characters suggest that EC was the only important and significant character accounting for 42% of the variation on CC. The high correlation of mean girth with yield and bark thickness showed that it is possible to obtain high yielding young ortets through early selection of these characters

Evaluation of milled pearl millet in the feeding of growing rabbits

Two experiments were carried out in order to estimate the nutritional value and the performance of growing rabbits fed different levels of pearl millet (ADR 7010). In the digestibility trial, nutritional values of pearl millet were determined in 22 45-day-old New Zealand White rabbits, allotted in a completely randomized design, subjected to two treatments - a reference diet and a test diet with 70% of its volume composed of reference diet and 30% of pearl millet - and 11 replications. The apparent digestibility values of dry matter, crude protein, neutral detergent fiber and gross energy of the pearl millet were 88.7, 85.4, 24.4 and 75.0%, respectively. In the performance trial, 120 32-day-old New Zealand White rabbits were used. Rabbits were allotted in a completely randomized design and subjected to six treatments, with 10 replications and two animals for each experimental unit. The diets were formulated with increasing levels of pearl millet (20, 40, 60, 80 and 100%), substituting the corn in the reference diet, according to the digestible energy. No differences were observed in daily feed intake, daily weight gain, feed conversion, carcass traits and feed cost per kilogram of rabbit. Regardless of the amount of corn substituted, pearl can replace corn in diets for growing rabbits

Shelf life of minimally processed pineapples treated with ascorbic and citric acids

The purpose of this research was to determine the shelf life of minimally processed (MP) 'Pérola' pineapples treated with ascorbic acid (AA) and citric acid (CA) based on physical, chemical, sensorial and microbiological attributes. Slices were dipped into drinking water (control) or combined solutions of AA:CA (%) (1.0:0.5 and 1.0:1.0) with sodium hypochlorite (NaClO 20 mg L-1) for 30 seconds. The samples were conditioned in polyethylene terephtalate packages and stored at 4±1 °C per 13 days. The low peroxidase activity in the slices treated with antioxidant combinations was related to low pH values observed in these samples. The treatments 1.0:0.5 and 1.0:1.0 (AA:CA, %) favored maintenance of the initial a* values and avoided the pulp browning. The ascorbic acid increased more than double on the 2nd day in the treated slices. By the 4th day the CO2 values suggested a higher respiratory activity in the slices treated with anti-browning compounds. The antioxidant treatments did not produce detectable residual flavors in the MP pineapple. Regardless of microbiological safety during the 13 days of cold storage, the control slices can be kept by 6 days, afterwards the color and dehydration become strong enough to affect the appearance. On the other hand, MP 'Pérola' pineapples treated with 1.0:0.5 (AA:CA, %) and NaClO (20 mg L-1) can be stored for 8 days at 4±1 ºC, which represents the extension of the shelf life in 2 days. After this period the overripe odor starts to develop