Body Mass Index, Cigarette Smoking, and Alcohol Consumption and Cancers of the Oral Cavity, Pharynx, and Larynx: Modeling Odds Ratios in Pooled Case-Control Data

study-specific results, their findings should be interpreted with caution

Padrões dietéticos e câncer oral e de faringe: um estudo caso-controle no Rio de Janeiro, Brasil

Investigou-se a associação entre padrões de dieta e câncer oral, como parte de um estudo multicêntrico latino-americano caso-controle de base hospitalar e incluiu 210 casos incidentes e 251 controles. Dados de consumo alimentar foram coletados por Questionário de Freqüência de Consumo Alimentar (QFCA). Análise fatorial identificou padrões alimentares, que foram categorizados em tercis. Calculou-se odds ratio (OR) com intervalo de 95 por cento de confiança (IC95 por cento ) por regressão logística múltipla não condicional. Os padrões "prudente", caracterizado em maioria por frutas e vegetais, e o padrão tradicional, por arroz e feijão, apresentaram associação inversa com o câncer oral para o mais elevado tercil, respectivamente: OR = 0,44; IC95 por cento : 0,25-0,75, valor de p de tendência (ptend) = 0,03; OR = 0,53; IC95 por cento : 0,30-0,93, ptend = 0,06. O padrão "lanches" não foi associado ao câncer oral. Além da proteção ao câncer oral conferida por dieta rica em vegetais e frutas, nossos dados sugerem que a dieta "tradicional" brasileira contendo em sua maioria arroz e feijão pode oferecer proteção ao câncer oral

OFFSPRING IN RESPONSE TO PARENTAL FEMALE DENSITIES IN THE FRUIT FLY PARASITOID DIACHASMIMORPHA LONGICAUDATA (HYMENOPTERA: BRACONIDAE: OPIINAE)

As part of an evaluation of the braconid parasitoid Diachasmimorpha longicaudata (Ashmead) as a biocontrol agent of Ceratitis capitata (Wiedemann) in Brazil, the aims in the current study were to find the best parental ratio of females to males in the rearing cages in order to get the highest female biased offspring in the parasitoid rearing process, and to verify the parasitism efficiency on C. capitata according to parental female densities. Three treatments were assessed: T1 (20 females: 20 males), T2 (60 females: 20 males) and T3 (100 females: 20 males). Ten late-third instars of C. capitata were offered daily to each female parasitoid from the 1st to the 12th d of age. The parental female productivity, fecundity, offspring sex ratio, percentage of parasitoid emergence, and daily mortality of parental females and males at different female/male densities were evaluated. The results indicated that numbers higher than 20 parental females did not affect offspring sex ratio, overall offspring production, nor the percent parasitism. Female biased offspring occurred in all three parental female/male ratios analyzed in this study, except that predominately males developed from parasitoid eggs laid in the age interval 1-2 d post emergence. Higher parasitoid female productivity and fecundity were found at the 1:1 female/male per cage density whereas lower productivity and fecundity were recorded at the 5:1 female/male ratio. Higher female/male ratio in the parental cages increased the mortality rate of females but did not influence the number of parental male deaths. The results may facilitate advancement of an optimum mass-rearing system to aid in control of C. capitata in Brazil.

Polydimethylsiloxane: a new contrast material for localization of occult breast lesions

Background. The radioguided localization of occult breast lesions (ROLL) technique often utilizes iodinated radiographic contrast to assure that the local injection of (99m)Tc-MAA corresponds to the location of the lesion under investigation. However, for this application, this contrast has several shortcomings. The objective of this study was to evaluate the safety, effectiveness and technical feasibility of the use of polydimethylsiloxane (PDMS) as radiological contrast and tissue marker in ROLL. Materials and methods. The safety assessment was performed by the acute toxicity study in Wistar rats (n = 50). The radiological analysis of breast tissue (n = 32) from patients undergoing reductive mammoplasty was used to verify the effectiveness of PDMS as contrast media. The technical feasibility was evaluated through the scintigraphic and histologic analysis. Results. We found no toxic effects of PDMS for this use during the observational period. It has been demonstrated in human breast tissue that the average diameter of the tissue marked by PDMS was lower than when marked by the contrast medium (p <0.001). PDMS did not interfere with the scintigraphic uptake (p = 0.528) and there was no injury in histological processing of samples. Conclusions. This study demonstrated not only the superiority of PDMS as radiological contrast in relation to the iodinated contrast, but also the technical feasibility for the same applicability in the ROLL.

The inducing NO-vasodilation by chemical reduction of coordinated nitrite ion in cis-[Ru(NO(2))L(bpy)(2)](+) complex

The synthesis of [Ru(NO(2)) L(bpy)(2)](+) (bpy = 2,2'-bipyridine and L = pyridine (py) and pyrazine (pz)) can be accomplished by addition of [Ru(NO) L(bpy) 2](PF(6))(3) to aqueous solutions of physiological pH. The electrochemical processes of [Ru(NO2) L(bpy) 2]+ in aqueous solution were studied by cyclic voltammetry and differential pulse voltammetry. The anodic scan shows a peak around 1.00 V vs. Ag/AgCl attributed to the oxidation process centered on the metal ion. However, in the cathodic scan a second peak around-0.60 V vs. Ag/AgCl was observed and attributed to the reduction process centered on the nitrite ligand. The controlled reduction potential electrolysis at-0.80 V vs. Ag/AgCl shows NO release characteristics as judged by NO measurement with a NO-sensor. This assumption was confirmed by ESI/MS(+) and spectroelectrochemical experiment where cis-[Ru(bpy)(2)L(H(2)O)](2+) was obtained as a product of the reduction of cis-[Ru(II)(NO(2)) L(bpy)(2)](+). The vasorelaxation observed in denuded aortic rings pre-contracted with 0.1 mu mol L(-1) phenylephrine responded with relaxation in the presence of cis-[RuII(NO2) L(bpy) 2]+. The potential of rat aorta cells to metabolize cis-[RuII(NO(2)) L(bpy)(2)](+) was also followed by confocal analysis. The obtained results suggest that NO release happens by reduction of cis-[RuII(NO(2)) L(bpy)(2)](+) inside the cell. The maximum vasorelaxation was achieved with 1 x 10(-5) mol L(-1) of cis-[RuII(NO(2)) L(bpy)(2)](+) complex.

Pimarane-type Diterpenes: Antimicrobial Activity against Oral Pathogens

Seven pimarane type-diterpenes re-isolated from Viguiera arenaria Baker and two semi-synthetic pimarane derivatives were evaluated in vitro against the following main microorganisms responsible for dental caries: Streptococcus salivarius, S. sobrinus, S. mutans, S. mitis, S. sanguinis and Lactobacillus casei. The compounds ent-pimara-8(14), 15-dien-19-oic acid (PA); ent-8(14), 15-pimaradien-3 beta-ol; ent-15-pimarene-8 beta, 19-diol; ent-8(14), 15-pimaradien-3 beta-acetoxy and the sodium salt derivative of PA were the most active compounds, displaying MIC values ranging from 2 to 8 mu g.mL(-1). Thus, this class of compounds seems promising as a class of new effective anticariogenic agents. Furthermore, our results also allow us to conclude that minor structural differences among these diterpenes significantly influence their antimicrobial activity, bringing new perspectives to the discovery of new natural compounds that could be employed in the development of oral care products.

Antimicrobial Activity of Diterpenes from Viguiera arenaria against Endodontic Bacteria

Six pimarane-type diterpenes isolated from Viguiera arenaria Baker and two semi-synthetic derivatives were evaluated in vitro against a panel of representative microorganisms responsible for dental root canal infections. The microdilution method was used for the determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia, Prevotella buccae, Fusobacterium nucleatum, Bacteroides fragilis, Actinomyces naeslundii, Actinomyces viscosus, Peptostreptococcus micros, Enterococcus faecalis and Aggregatibacter actinomycetemcomitans. The compounds ent-pimara-8(14), 15-dien-19-oic acid, its sodium salt and ent-8(14), 15-pimaradien-3 beta-ol were the most active, displaying MIC values ranging from 1 to 10 mu g mL(-1). The results also allow us to conclude that minor structural differences among these diterpenes significantly influence their antimicrobial activity, bringing new perspectives to the discovery of new chemicals for use as a complement to instrumental endodontic procedures.

Anticariogenic Properties of ent-Pimarane Diterpenes Obtained by Microbial Transformation

In the present work, the anticariogenic activities of three pimarane-type diterpenes obtained by fungal biotransformation were investigated. Among these metabolites, ent-8(14), 15-pimaradien-19-ol was the most active compound, displaying very promising MIC values (ranging from 1.5 to 4.0 mu g mL(-1)) against the main microorganisms responsible for dental caries: Streptococcus salivarius, S. sobrinus, S. mutans, S. mitis, S. sanguinis, and Lactobacillus casei. Time kill assays performed with ent-8(14), 15-pimaradien-19-ol against the primary causative agent S. mutans revealed that this compound only avoids growth of the inoculum in the first 12 h (bacteriostatic effect). However, its bactericidal effect is clearly noted thereafter (between 12 and 24 h). The curve profile obtained by combining ent-8(14), 15-pimaradien-19-ol and chlorhexidine revealed a significant reduction in the time necessary for killing S. mutans compared with each of these two chemicals alone. However, no synergistic effect was observed using the same combination in the checkerboard assays against this microorganism. In conclusion, our results point out that ent-8(14), 15-pimaradien-19-ol is an important metabolite in the search for new effective anticariogenic agents.

Cyclooligomerisation of azido-alkyne-functionalised sugars: synthesis of 1,6-linked cyclic pseudo-galactooligosaccharides and assessment of their sialylation by Trypanosoma cruzi trans-sialidase

Cyclic pseudo-galactooligosaccharides were synthesized by cyclooligomerisation of isomeric azido-alkyne derivatives of beta-D-galactopyranose under Cu(I)-catalysed azide-alkyne 1,3-dipolar cycloaddition reaction conditions. The principal products isolated were cyclic dimers and trimers, with lower amounts of cyclic tetramer and pentamer also evident in some cases. Molecular mechanics calculations suggest very compact but flexible structures for the cyclic trimers, with secondary OH groups exposed outside the macrocycle and available for enzymatic glycosylation. The cyclic dimers and trimers represent a new type of acceptor substrate for Trypanosoma cruzi trans-sialidase, giving rise to doubly and triply sialylated glycomacrocycles, respectively.

Screening of Filamentous Fungi to Identify Biocatalysts for Lupeol Biotransformation

The goal of the study was to evaluate the ability of filamentous fungi to biotransform the pentacyclic triterpene lupeol. The microbial transformations were carried out in shake flasks in different media. Experiments were also run with control flasks. Samples of each culture were taken every 24 hours, extracted with ethyl acetate, and analyzed by GC-MS. The biotransformation of lupeol by Aspergillus ochraceus and Mucor rouxii afforded two compounds in each culture, which were detected in the cultures developed for more than seven days only in the Koch's K1 medium. The obtained data demonstrated that A. ochraceus is a good biocatalyst to introduce double bonds in the lupeol structure, whereas M. rouxii exhibits ability to biocatalyze oxygen insertions in that pentacyclic triterpene. Mass spectrometry was demonstrated to be an efficient analytical method to select promising biocatalysts for the compound investigated in this study. The biotransformation processes were influenced by the culture medium and incubation period. The obtained results open the perspective of using A. ochraceus and M. rouxii in pentacyclic triterpene biotransformations.

Histometry of the sublingual gland in male and female mice (Mus musculus) infected with the RAL strain of the Chagas parasite, Trypanosoma cruzi

Trypanosoma cruzi. The aim of this work was to analyze histologically and histometrically the sublingual gland of mice infected with the RAL strain of T cruzi, according to the sex. Swiss mice (Mus musculus) were inoculated with 2 x 10(4) blood trypomastigotes of the RAL strain of T cruzi. In the peak of the parasitemia (12th day) the mice were sacrificed, and the sublingual glands were fixed in ALFAC. HE-stained histological sections were evaluated histometrically. The parasitemia was higher in females. Histopatologically, acini of the infected animals were smaller, with scanty production of secretion, and smaller striated ducts. The nuclei of the demilunes were smaller and showed amastigote nests in the cytoplasm. Karyometrically, nuclei of the acini, demilunes and striated ducts were smaller in the infected mice. Stereologically, it was observed that relative volumes of acini and ducts were smaller and, inversely, relative volumen were greater for the conjunctive tissue in the infected males. The surface densities of acini and ducts were bigger and the diameter and thickness of the wall were smaller in this group. On the other hand, relative volume of acini was smaller and those of the ducts and conjunctive tissue were bigger in the infected females. The diameter and thickness of the wall of acini were smaller, and those of the striated ducts were bigger in this group. The RAL strain of T cruzi caused general atrophy in the sublingual gland, with numerous nests of parasites in the glandular parenchyma.

Antileishmanial Activity of the Hydroalcoholic Extract of Miconia langsdorffii, Isolated Compounds, and Semi-Synthetic Derivatives

The in vitro activity of the crude hydroalcoholic extract of the aerial parts of Miconia langsdorffii Cogn. was evaluated against the promastigote forms of L. amazonensis, the causative agent of cutaneous leishmaniasis in humans. The bioassay-guided fractionation of this extract led to identification of the triterpenes ursolic acid and oleanolic acid as the major compounds in the fraction that displayed the highest activity. Several ursolic acid semi-synthetic derivatives were prepared, to find out whether more active compounds could be obtained. Among these ursolic acid-derived substances, the C-28 methyl ester derivative exhibited the best antileishmanial activity.

Reactivity, photolability, and computational studies of the ruthenium nitrosyl complex with a substituted cyclam fac-[Ru(NO)Cl(2)(kappa(3)N(4),N(8),N(11)(1-carboxypropyl)cyclam)]Cl center dot H(2)O

Chemical reactivity, photolability, and computational studies of the ruthenium nitrosyl complex with a substituted cyclam, fac-[Ru(NO)Cl(2)(kappa(3)N(4),N(8),N(11)(1-carboxypropyl)cyclam)]Cl center dot H(2)O ((1-carboxypropyl) cyclam = 3-(1,4,8,11-tetraazacyclotetradecan-1-yl) propionic acid)), (I) are described. Chloride ligands do not undergo aquation reactions (at 25 degrees C, pH 3). The rate of nitric oxide (NO) dissociation (k(obs-NO)) upon reduction of I is 2.8 s(-1) at 25 +/- 1 degrees C (in 0.5 mol L(-1) HCl), which is close to the highest value found for related complexes. The uncoordinated carboxyl of I has a pK(a) of similar to 3.3, which is close to that of the carboxyl of the non coordinated (1-carboxypropyl) cyclam (pK(a) = 3.4). Two additional pK(a) values were found for I at similar to 8.0 and similar to 11.5. Upon electrochemical reduction or under irradiation with light (lambda(irr) = 350 or 520 nm; pH 7.4), I releases NO in aqueous solution. The cyclam ring N bound to the carboxypropyl group is not coordinated, resulting in a fac configuration that affects the properties and chemical reactivities of I, especially as NO donor, compared with analogous trans complexes. Among the computational models tested, the B3LYP/ECP28MDF, cc-pVDZ resulted in smaller errors for the geometry of I. The computational data helped clarify the experimental acid-base equilibria and indicated the most favourable site for the second deprotonation, which follows that of the carboxyl group. Furthermore, it showed that by changing the pH it is possible to modulate the electron density of I with deprotonation. The calculated NO bond length and the Ru/NO charge ratio indicated that the predominant canonical structure is [Ru(III)NO], but the Ru-NO bond angles and bond index (b.i.) values were less clear; the angles suggested that [Ru(II)NO(+)] could contribute to the electronic structure of I and b.i. values indicated a contribution from [Ru(IV)NO(-)]. Considering that some experimental data are consistent with a [Ru(II)NO(+)] description, while others are in agreement with [Ru(III)NO], the best description for I would be a linear combination of the three canonical forms, with a higher weight for [Ru(II)NO(+)] and [Ru(III)NO].

Pulse train fluorescence technique for measuring triplet state dynamics

We report on a method to study the dynamics of triplet formation based on the fluorescence signal produced by a pulse train. Basically, the pulse train acts as sequential pump-probe pulses that precisely map the excited-state dynamics in the long time scale. This allows characterizing those processes that affect the population evolution of the first excited singlet state, whose decay gives rise to the fluorescence. The technique was proven to be valuable to measure parameters of triplet formation in organic molecules. Additionally, this single beam technique has the advantages of simplicity, low noise and background-free signal detection. (C) 2011 Optical Society of America

Minor and Unsystematic Cortical Topographic Changes of Attention Correlates between Modalities

In this study we analyzed the topography of induced cortical oscillations in 20 healthy individuals performing simple attention tasks. We were interested in qualitatively replicating our recent findings on the localization of attention-induced beta bands during a visual task [1], and verifying whether significant topographic changes would follow the change of attention to the auditory modality. We computed corrected latency averaging of each induced frequency bands, and modeled their generators by current density reconstruction with Lp-norm minimization. We quantified topographic similarity between conditions by an analysis of correlations, whereas the inter-modality significant differences in attention correlates were illustrated in each individual case. We replicated the qualitative result of highly idiosyncratic topography of attention-related activity to individuals, manifested both in the beta bands, and previously studied slow potential distributions [2]. Visual inspection of both scalp potentials and distribution of cortical currents showed minor changes in attention-related bands with respect to modality, as compared to the theta and delta bands, known to be major contributors to the sensory-related potentials. Quantitative results agreed with visual inspection, supporting to the conclusion that attention-related activity does not change much between modalities, and whatever individual changes do occur, they are not systematic in cortical localization across subjects. We discuss our results, combined with results from other studies that present individual data, with respect to the function of cortical association areas.