Effects of infrared light laser therapy on in vivo and in vitro periodontitis models.

BACKGROUND: This study evaluated the effects of infrared light laser therapy (ILLT) on ligature-induced periodontitis in rats using micro-computed tomography (micro-CT), histology, fibroblast migration, and viability analysis. METHODS: Forty-eight rats were randomly distributed into three groups: control (no periodontitis), PDC (periodontitis without laser therapy), and PD+L (periodontitis with laser therapy). Periodontitis was induced by ligature placement for 4 weeks. The 12-week-old rats (baseline) were subjected to laser treatment and euthanized 30 days after. After treatment, the mandibular first molars were prepared for micro-CT scanning, and histological sections were assessed as to the cementoenamel junction, alveolar bone crest, and polymorphonuclear (PMN) cell infiltration. In vitro assays were carried out to examine NIH/3T3 fibroblast viability after laser therapy. RESULTS: Migration and cell viability assays revealed that the ILLT maintained fibroblast cell viability with 4 J/cm2 , reaching 100% healing. The control group (at baseline and 30 days) presented a statistically significant difference from the PDC group at 30 days in terms of distance from the cementoenamel junction to the alveolar bone crest (CEJ-ABC). The PD+L group showed a statistically substantial difference from the PDC group at 30 days in terms of trabecular thickness (Tb.Th), degree of anisotropy (DA), and closed porosity percentage (Po%). CONCLUSION: ILLT seemed to preserve the bone structure in the in vivo periodontitis induction model at 30 days and did not reduce cell viability or increase fibroblast migration in vitro. The ILLT provides positive effects on mandibular bone microstructure.

Chemical Characterization and Phytotoxic Effects of the Aerial Parts of Ruzigrass (Urochloa ruziziensis).

Studies of the phytotoxic effects between plants can be a crucial tool in the discovery of innovative compounds with herbicide potential. In this sense, we can highlight ruzigrass (Urochloa ruziziensis), which is traditionally used in the crop rotation system in order to reduce weed emergence. The aim of this work was to characterize the secondary metabolites of ruzigrass and to evaluate its phytotoxic effects. In total, eight compounds were isolated: friedelin, oleanolic acid, α-amyrin, 1-dehydrodiosgenone, sitosterol and stigmasterol glycosides, tricin and p-coumaric acid. Phytotoxic effects of the crude methanolic extract and fractions of ruzigrass were assessed using germination rate, initial seedling growth, and biomass of Bidens pilosa, Euphorbia heterophylla and Ipomoea grandifolia. Chemometric analysis discriminated the weed species into three groups, and B. pilosa was the most affected by fractions of ruzigrass. The phytotoxic activities of 1-dehydrodiosgenone, tricin, and p-coumaric acid are also reported, and p-coumaric acid and 1-dehydrodiosgenone were active against B. pilosa.

Genotype-dependent changes of gene expression during somatic embryogenesis in oil palm hybrids (Elaeis oleifera x E. guineensis).

To understand the molecular processes triggered during the different steps of somatic embryogenesis (SE) in oil palm, the expression of 19 genes associated to SE identified in proteomic and transcriptomic studies was investigated by qRT-PCR. To evaluate the differential expression of these genes, two interspecific hybrid genotypes (Elaeis oleifera x Elaeis guineensis) contrasting for the acquisition of embryogenic competence were used. Aclorophyllated leaves of both hybrids, one responsive (B351733) and the other non-responsive (B352933) to SE were submitted to callus induction and collected at different time points: 0 (before induction), 14, 30, 90 and 150 days of callus induction (doi). The results obtained showed that all evaluated genes were downregulated at 14 doi in the responsive genotype when compared to the non-responsive. It was also possible to observe that most of the genes changed their expression behavior at 30 doi and were upregulated thereafter until 150 doi, with the exception of the pathogenesis-related PRB1-3-like (PRB1-3) gene, which did not show differential expression at 30 doi and was downregulated at 90 and 150 doi when compared to the non-responsive hybrid. These results indicate that 30 doi is a turning point in gene expression, probably associated to embryogenic competence acquisition. We also show that the expression behavior of the responsive genotype is more stable than that of the non-responsive when the different induction time points are compared to 0 doi (before induction). Moreover, the results obtained in this study corroborate our hypothesis that the regulation of genes involved in the control of oxidative stress and energy metabolism are crucial for the acquisition of embryogenic competence in oil palm.

A multi-laboratory evaluation of microelectrode array-based measurements of neural network activity for acute neurotoxicity testing.

There is a need for methods to screen and prioritize chemicals for potential hazard, including neurotoxicity. Microelectrode array (MEA) systems enable simultaneous extracellular recordings from multiple sites in neural networks in real time and thereby provide a robust measure of network activity. In this study, spontaneous activity measurements from primary neuronal cultures treated with three neurotoxic or three non-neurotoxic compounds was evaluated across four different laboratories. All four individual laboratories correctly identifed the neurotoxic compounds chlorpyrifos oxon (an organophosphate insecticide), deltamethrin (a pyrethroid insecticide) and domoic acid (an excitotoxicant). By contrast, the other three compounds (glyphosate, dimethyl phthalate and acetaminophen) considered to be non-neurotoxic ("negative controls"), produced only sporadic changes of the measured parameters. The results were consistent across the different laboratories, as all three neurotoxic compounds caused concentration-dependent inhibition of mean firing rate (MFR). Further, MFR appeared to be the most sensitive parameter for effects of neurotoxic compounds, as changes in electrical activity measured by mean frequency intra burst (MFIB), and mean burst duration (MBD) did not result in concentration-response relationships for some of the positive compounds, or required higher concentrations for an effect to be observed. However, greater numbers of compounds need to be tested to confirm this. The results obtained indicate that measurement of spontaneous electrical activity using MEAs provides a robust assessment of compound effects on neural network function.

Analysis of clay smoking pipes from archeological sites in the region of the Guanabara Bay (Rio de Janeiro, Brazil) by FT-IR.

In this study, twenty samples of clay smoking pipes excavated in an 18km(2) area between the Macacu and Caceribu rivers, in the municipality of Itaboraí, Rio de Janeiro, Brazil were analyzed by FT-IR technique. The samples, excavated in different archeological sites of the region, are dated between the seventeenth and the nineteenth centuries and are part of the material culture left by Africans and African descendants that lived in the complex. FT-IR analyses and complementary SEM-EDS studies showed that the clay paste used in the manufacture of smoking pipes, mostly handcrafted, is composed of quartz, feldspar, phyllosilicates and iron oxides. Multivariate statistical tests (PCA) were applied to FT-IR data to assess the interactions between the archeological sites. The results indicated that one archeological site - Macacu IV - is greatly related to the other sites. The results obtained have helped archeologists and anthropologists in better understanding the manufacturing process employed in ancient ceramic artifacts produced during the period of colonial Brazil.

Evaluation of marginal and internal fit of ceramic and metallic crown copings using x-ray microtomography (micro-CT) technology.

STATEMENT OF PROBLEM: Prosthetic crown fit to the walls of the tooth preparation may vary depending on the material used for crown fabrication. PURPOSE: The purpose of this study was to compare the marginal and internal fit of crown copings fabricated from 3 different materials. MATERIAL AND METHODS: The selected materials were zirconia (ZirkonZahn system, group Y-TZP), lithium disilicate (IPS e.max Press system, group LSZ), and nickel-chromium alloy (lost-wax casting, group NiCr). Five specimens of each material were seated on standard dies. An x-ray microtomography (micro-CT) device was used to obtain volumetric reconstructions of each specimen. Points for fit measurement were located in Adobe Photoshop, and measurements were obtained in the CTAn SkyScan software environment. Marginal fit was measured at 4 points and internal fit at 9 points in each coping. Mean measurements from the 3 groups were compared by analysis of variance (ANOVA) at the 5% significance level, and between-group differences were assessed with the Tukey range test. RESULTS: The nickel-chromium alloy exhibited the best marginal fit overall, comparable with zirconia and significantly different from lithium disilicate. Lithium disilicate exhibited the lowest mean values for internal fit, similar to zirconia and significantly different from the nickel-chrome alloy. CONCLUSIONS: The marginal and internal fit parameters of the 3 tested materials were within clinically acceptable range.

Genetic architecture of palm oil fatty acid composition in cultivated oil palm (Elaeis guineensis Jacq.) compared to its wild relative E. oleifera (H.B.K) Cortés.

We searched for quantitative trait loci (QTL) associated with the palm oil fatty acid composition of mature fruits of the oil palm E. guineensis Jacq. in comparison with its wild relative E. oleifera (H.B.K) Cortés. The oil palm cross LM2T x DA10D between two heterozygous parents was considered in our experiment as an intraspecific representative of E. guineensis. Its QTLs were compared to QTLs published for the same traits in an interspecific Elaeis pseudo-backcross used as an indirect representative of E. oleifera. Few correlations were found in E. guineensis between pulp fatty acid proportions and yield traits, allowing for the rather independent selection of both types of traits. Sixteen QTLs affecting palm oil fatty acid proportions and iodine value were identified in oil palm. The phenotypic variation explained by the detected QTLs was low to medium in E. guineensis, ranging between 10% and 36%. The explained cumulative variation was 29% for palmitic acid C16:0 (one QTL), 68% for stearic acid C18:0 (two QTLs), 50% for oleic acid C18:1 (three QTLs), 25% for linoleic acid C18:2 (one QTL), and 40% (two QTLs) for the iodine value. Good marker co-linearity was observed between the intraspecific and interspecific Simple Sequence Repeat (SSR) linkage maps. Specific QTL regions for several traits were found in each mapping population. Our comparative QTL results in both E. guineensis and interspecific materials strongly suggest that, apart from two common QTL zones, there are two specific QTL regions with major effects, which might be one in E. guineensis, the other in E. oleifera, which are independent of each other and harbor QTLs for several traits, indicating either pleiotropic effects or linkage. Using QTL maps connected by highly transferable SSR markers, our study established a good basis to decipher in the future such hypothesis at the Elaeis genus level.

The mismatch negativity (MMN) potential as a tool for the functional mapping of temporal lobe epilepsies.

Temporal lobe epilepsies are associated with cognitive dysfunctions in memory which are important clues currently used clinically for the lateralization of the epileptic focus in evaluations for epilepsy surgery. Because these lobes also contain the primary auditory cortex, the study of auditory evoked potentials (AEPs) is a candidate, not yet established, complementary method to characterize epilepsy-induced dysfunction. We aimed to establish the clinical usefulness of auditory evoked potentials for the study of pediatric symptomatic temporal lobe epilepsies. A group of 17 patients (ages 4-16) with symptomatic epilepsies undergoing evaluation for epilepsy surgery epilepsy was submitted to auditory evoked potentials using 35-channel scalp EEG recordings. A control group of 10 healthy volunteers was studied with the same protocol. The P100 and mismatch negativity (MMN) potential latencies and normalized amplitudes were studied. We also performed a voxel-based lesion-symptom mapping (VLSM) to determine the anatomical areas associated with changes in the AEPs. Eleven patients had temporal lobe epilepsy, three had frontal lobe epilepsy, and three had occipital lobe epilepsy. Latencies for the P100 were normal in 15/17 and in 11/17 for the MMN, with no consistent correlation with the epilepsy type. The MMN amplitude was abnormal in 7/17 patients, all with temporal lobe epilepsies (sensitivity of 64%). Of these patients, four had a decreased MMN associated with a Heschl's gyrus lesion in the VLSM, and three had an increased MMN associated with hippocampal lesion. No extratemporal epilepsy showed MMN amplitude abnormalities (specificity of 100%). The P100 amplitude was abnormal in 3/17, two with temporal and one with frontal lobe epilepsies. The auditory MMN has a high specificity but a low sensitivity for temporal lobe epilepsy in symptomatic pediatric epilepsies. Amplitude decreases of the MMN are associated with homolateral Heschl's gyrus lesions, and MMN increases with hippocampal lesions.

Semi-automatic version of the potentiometric titration method for characterization of uranium compounds.

The potentiometric titration method was used for characterization of uranium compounds to be applied in intercomparison programs. The method is applied with traceability assured using a potassium dichromate primary standard. A semi-automatic version was developed to reduce the analysis time and the operator variation. The standard uncertainty in determining the total concentration of uranium was around 0.01%, which is suitable for uranium characterization and compatible with those obtained by manual techniques.

Repetibilidade da produção de cachos de híbridos interespecíficos entre o caiaué e o dendezeiro / Repeatability for bunch production in interspecific hybrids between caiaué and african oil palm

A hibridação interespecífica entre o caiaué (Elaeis oleífera (Kunth) Cortés) e o dendezeiro (E. guineensis Jacq.) tem sido explorada com o objetivo de desenvolver cultivares tão produtivas quanto as de dendezeiro, aliada à resistência a pragas e doenças, principalmente o amarelecimento fatal, elevada taxa de ácidos graxos insaturados e redução de porte características do caiaué. Por ser uma cultura perene com longo ciclo de produção, além dos altos custos para manutenção e avaliação dos experimentos de melhoramento genético, é necessário definir o período mínimo de avaliação para que a seleção dos híbridos seja realizada com eficiência e mínimo dispêndio de tempo e recursos. Este estudo teve como objetivo estimar os coeficientes de repetibilidade dos caracteres número de cachos, peso total de cachos e peso médio de cachos de híbridos interespecíficos e definir o número de anos consecutivos de avaliação necessário para seleção eficiente dos melhores cruzamentos e indivíduos. Os coeficientes de repetibilidade foram estimados pelos métodos da análise de variância, componentes principais com base na matriz de covariância (CPCV) e de correlações, e análise estrutural com base na matriz de correlações. O método dos CPCV demonstrou ser o mais adequado para o estudo da repetibilidade da produção de cachos, indicando quatro anos consecutivos de avaliação para selecionar progênies, representadas por dez plantas, com coeficientes de determinação (R²) superiores a 85 por cento, e que para seleção individual de plantas são necessários pelo menos seis anos consecutivos de avaliação para atingir R² superior a 80 por cento.

Interspecific hybridization between the caiaué (Elaeis oleífera (Kunth) Cortés) and the african oil palm (E. guineensis Jacq.) has been exploited with the objective of developing varieties as productive as African oil palm and with the pest and disease resistance, reduced height and high levels of insaturated oils characteristic of the caiaué. Perennial crops with long production cycles and high costs for maintenance and evaluation of improvement experiments require definition of minimum evaluation periods for efficient and low cost selection of hybrids. This study estimated the repeatability coefficients of the characters bunch number, total weight of bunches and average bunch weight of interspecific hybrids and determined the number of consecutive years of evaluation required for efficient selection of the best crosses and individuals. The repeatability coefficients were estimated by four methods: analysis of variance, principal components based on the covariance (CPCV) and correlation matrix, and structural analysis based on the correlation matrix. The CPCV method was the most appropriate for the study of the repeatability of bunch production. Four consecutive years of evaluation are required to select progenies, represented by ten plants, with determination coefficients (R²) up to 85 percent, and at least six consecutive years of evaluation are necessary to select individuals, with R² up to 80 percent.

Characterization of iron, copper and zinc levels in the colostrum of mothers of term and pre-term infants before and after pasteurization.

Pasteurization is a thermal treatment applied to the milk used in human milk banks so as to provoke the thermic inactivation of pathogenic micro-organisms, with the aim of avoiding contamination of milk that will be offered to new-born infants in clinical conditions very often demanding special care. The literature has very little data available relating to the effect of pasteurization on the concentration of oligo-elements in human milk. The objective of this study was to evaluate the effect of pasteurization on the concentrations of iron (Fe), copper (Cu) and zinc (Zn) in the colostrum of mothers of pre-term (PT) and term (T) infants. Samples were collected from the day of birth to the seventh day after birth. The oligo-elements were analyzed using the total reflection X-ray fluorescence technique with synchrotron radiation. The following results of Fe, Cu and Zn (means +/- SD) were obtained for the PT and T colostrum samples, non-pasteurized and pasteurized, respectively: PT: 1.96 +/- 0.73 mg/l Fe/Zn/5.39 +/- 2.73 mg/l Zn; T: 1.71 +/- 1.01 mg/l Fe/1.46 +/- 0.99 mg/l Fe, 0.54 +/- 0.29 mg/l Cu/0.49 +/- 0.19 mg/l Cu, 6.97 +/- 2.82 mg/l Zn/6.75 +/- 2.62 mg/l Zn. There was a significant reduction in the levels of Fe, Cu and Zn in the samples of pasteurized colostrum. These results suggest that, despite the observance of a diminution in the levels of Fe, Cu and Zn in the samples of pasteurized colostrum, the values fell within the acceptable range for the specific nutritional needs of new-born infants during this period of lactation.