Involvement of TLR6 in the induction of COX-2, PGE2 and IL-10 in macrophages by lipids from virulent S2P and attenuated R1A Babesia bovis strains.

Toll like receptors (TLRs) are involved in the modulation of diverse host genes expression through a complex network of signalling events that allow for an appropriate response to a microbial pathogen. In the present work we used TLR6KO mice in order to study the role of TLR6 in the immune discrimination of lipids from two Babesia bovis strains, attenuated R1A (LA) and virulent S2P (LV), and the consequent macrophage activation. We demonstrated that TLR6 is required for lipid body induction in murine peritoneal macrophages by both LA and LV. Interestingly, as regards IL-10 and COX-2/PGE2 pathway induction by LA and LV, we observed differences in the biological effects produced by these lipid extracts. Our results indicate a role of TLR6 in the down-modulation of these immunoregulators only in the case of LA, whereas this receptor was not implicated in pro-inflammatory TNFα, IL-6 and KC release induced by LA. Remarkably, LV did not exert the down-modulatory effect observed for LA, supporting the notion that LA and LV possess different lipid composition that could correlate with the polar pathogenic effect of both B. bovis strains.

Matrix metalloproteinase 9 -1562C/T polymorphism increased protein levels in patients with colorectal cancer in a sample from southeastern Brazil.

We examined whether the allelic and/or genotypic profile of locus -1562C/T of the matrix metalloproteinase (MMP-9) gene influences the protein expression levels of MMP-9 in patients with colorectal cancer (CRC) compared with controls. A total of 104 patients with CRC and 84 controls were evaluated. Peripheral blood was collected from both groups and DNA extraction was performed for -1562C/T genotyping; the plasma was used for MMP-9 quantification. The CT genotype was associated with increased MMP-9 expression (P = 0.0211). High levels of protein, independently of polymorphisms, were observed in the patient group (P < 0.0001) compared to controls. Mucinous tumors with signet ring cells were more frequent in females (P = 0.0177). Overall, patients older than 50 years showed a significant risk of developing CRC (P = 0.0001). MMP-9 plasma expression was increased in patients with CRC compared to controls, particularly in those with the heterozygous -1562CT genotype.

The ability of the Reciproc R25 instrument to reach the full root canal working length without a glide path.

AIM: To assess the frequency in which the Reciproc instrument reaches the full working length (FWL) of mandibular molar canals without a glide path. METHODOLOGY: From a pool of mandibular molars, 253 root canals were classified as straight (G1) and, 249 root canals as moderately curved (G2) following Schneider's method. A R25 Reciproc instrument (VDW, Munich, Germany) was advanced in the canals without any previous glide path. All cases where Reciproc instruments reached the FWL were classified as 'Reaching the FWL' (RFWL). When the FWL was not reached by the R25, the root canals were classified as 'Not Reaching the FWL' (NRFWL). Pearson's χ(2) test compared (i) the frequency distributions of root canals classified as RFWL and NRFWL for each group and (ii) the frequency distributions of NRFWL canals between the groups. RESULTS: In G1, 9 cases (3.56%) and in G2, 23 canals (9.34%) were classified as NRFWL. The difference between NRFWL and RFWL was significant in both groups (P = 0.00, χ(2) = 217.2 for G1; P = 0.00, χ(2) = 167.8 for G2). The frequency of NRFWL was significantly higher for G2 (P = 0.02, χ(2) = 5.452). CONCLUSION: The R25 Reciproc instrument is able to reach the FWL of straight- and moderate-curved mandibular molar canals without a glide path in a large proportion of cases.

Fluorescence as an analytical tool for assessing the conversion of oil into biodiesel.

In this work fluorescence-based method to assess the biodiesel production from different refined vegetable oils is presented. Four different refined oils (soybean, sunflower, canola, and corn) and their respective biodiesel were used and the fluorescence of the compounds contained in their compositions was taken as a probe. The results show that the fluorescence intensity of the biodiesel is lower than one verified in the vegetable oil. The data achieved point out that the ratio between the fluorescence intensity of biodiesel and oil is about 0.6 regardless of the vegetable oil feedstock investigated. Reduced content of fluorophores as well as low viscosity of the biodiesel regarding the oil have been raised as hypotheses to explain the low fluorescence intensity of the biodiesel. The results obtained may provide the basis for the development of an alternative method able to give fast and accurate information about the conversion of oil into biodiesel without the requirement of dilution or pre-treatment of the biodiesel.

Lipids from attenuated and virulent Babesia bovis strains induce differential TLR2-mediated macrophage activation.

Babesia bovis is an intraerythrocytic apicomplexan protozoa of cattle that causes an acute infection with parasite persistence. Babesiosis limitation depends on macrophages, essential effector cells of the host innate defense, which generate inflammatory cytokines and nitric oxide. Herein, we report quantitative differences in the lipid composition of merozoites from two B. bovis strains with polar behaviour: attenuated R1A and virulent S2P. Accordingly, we observed a distinct inflammatory response induced by the total lipids of R1A (L(A)) and S2P (L(V)) in murine peritoneal macrophages. L(A) and particularly its fractions phosphatidic acid and phosphatidylserine+phosphatidylinositol (PS+PI), produced a strong activation of these cells with lipid body formation, cyclooxygenase-2 expression and pro-inflammatory TNFalpha, IL-6 and KC secretion. Although L(V) did not activate these cells, the corresponding PS+PI fraction induced TNFalpha, IL-6 and KC release. Therefore, these facts might be suggesting the presence of an inhibitor in L(V). Furthermore, the employment of wild type and toll like receptor 2 knockout (TLR2KO) mice allowed us to demonstrate that macrophage activation by the stimulating lipid fractions was mediated through TLR2. Interestingly, only L(A) activated the extracellular signal-regulated kinases 1 and 2 (ERK1/2). Inhibitory studies employing UO126, indicated that the ERK pathway was required for TNFalpha, IL-6 and KC release. In conclusion, the absence of inflammatory response observed with the lipids of S2P virulent strain could constitute an evasion mechanism of the innate immune response enabling parasite establishment in the host.

Emergence of turbulence in an oscillating bose-einstein condensate.

We report on the experimental observation of vortex tangles in an atomic Bose-Einstein condensate (BEC) of ;{87}Rb atoms when an external oscillatory perturbation is introduced in the trap. The vortex tangle configuration is a signature of the presence of a turbulent regime in the cloud. We also show that this turbulent cloud suppresses the aspect ratio inversion typically observed in quantum degenerate bosonic gases during free expansion. Instead, the cloud expands keeping the ratio between their axis constant. Turbulence in atomic superfluids may constitute an alternative system to investigate decay mechanisms as well as to test fundamental theoretical aspects in this field.

Role of purines on hepatic ischemia-reperfusion lesions in rabbit.

In this work, we evaluate the effects of adenosine 5' triphosphate (ATP) on hepatic lesions caused by ischemia/reperfusion (I/R) in liver rabbit. Rabbits were pretreated with ATP (15 mg/kg IV) or saline solution 0.9% (SS), before the hepatic I/R procedure. We evaluated the effects of ATP on hepatic injury before and after I/R. The warm hepatic I/R procedure caused profound acute liver injury, as indicated by elevated serum aspartate aminotransferase, alanine aminotransferase, and lactic dehydrogenase levels, as well as a high apoptotic cell count. All these changes were attenuate by ATP treatment before the hepatic I/R procedure. These results suggested that ATP exerted protective effects on hepatic I/R lesions in the rabbit. This ATP effect may be related to improved energy metabolism during reperfusion in ischemic livers protecting against functional damage of cellular and subcellular membranes during lipid peroxidation.

l-Arginine supplementation protects against hepatic ischemia-reperfusion lesions in rabbits.

We evaluated the effects of a substrate in the biosynthesis of nitric oxide (NO)-l-arginine (LARG)-on hepatic lesions caused by ischemia/reperfusion (I/R) injury in rabbit livers. Rabbits were pretreated with LARG (150 mg/kg IV) or saline solution 0.9% (SS) before the hepatic I/R procedure. The effects of LARG on hepatic injury were evaluated before and after I/R. The warm hepatic I/R procedure produced profound acute liver injury, as indicated by elevated values of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactic dehydrogenase (LDH), as well as a high apoptotic cell count. All changes were attenuated by treatment with LARG before the hepatic I/R procedure. These results suggested that LARG produced protective effects on hepatic I/R lesions. This protective effect of LARG was probably associated with blocking generation of superoxide anions during the hepatic I/R procedure.

Protective effects of heparin on hepatic ischemia and reperfusion lesions in rabbits.

Because the role of heparin (HEP) in hepatic ischemia/reperfusion (I/R) injury is still not fully understood, we investigated the effects of treatment with HEP on hepatic I/R injury in rabbits. For I/R procedures, the portal vein and hepatic artery were occluded by a metallic clamp to promote ischemia. The clamp was removed after 30 minutes to allow reperfusion. Rabbits undergoing the I/R procedure were treated with HEP (100 U/kg) or saline solution 0.9% (SS). When compared with levels before I/R, the serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase, levels were increased by the hepatic I/R procedure, among rabbits treated with SS or HEP. However, the increase in these enzymes was lower among rabbits treated with HEP. Histologic analysis of hepatic tissue of rabbits undergoing I/R and treated with SS showed marked lesions in the central lobule with significant inflammatory infiltration. In contrast, a significant reduction in lesions caused by I/R was observed in the livers of rabbits treated with HEP. After starting reperfusion, we visualized apoptotic cells with nuclear staining among rabbits submitted to I/R and treated with SS, but not those treated with HEP. These results suggested that HEP was able to attenuate hepatic lesions caused by I/R in the livers of rabbits.

Effects of allopurinol on ischemia and reperfusion in rabbit livers.

In this work, we evaluated the effects of allopurinol (ALO), an inhibitor of xanthine oxidase (XO), on hepatic lesions caused by ischemia/reperfusion (I/R) in the rabbit liver. Rabbits were pretreated with ALO (10 mg/kg IV) or saline solution 0.9% before the hepatic I/R procedure. The effects of ALO on hepatic injury were evaluated before and after I/R. A standard, warm hepatic I/R procedure caused profound acute liver injury, as indicated by elevated serum aspartate aminotransferase, alanine aminotransferase, and lactic dehydrogenase levels, as well as a high apoptotic cell count. All of these changes were reversed by the administration of ALO before the hepatic I/R procedure. In conclusion, ALO exerted protective effects on hepatic I/R lesions. This protective effect of ALO was probably associated with blocking the generation of superoxide anions during the hepatic I/R procedure by inhibiting XO activity.

Cultivable bacteria in infected root canals as identified by 16S rRNA gene sequencing.

INTRODUCTION: Traditionally, cultivable bacteria isolated from infected root canals have been identified by phenotype-based methods. Because 16S ribosomal RNA (rRNA) gene sequencing has emerged as a more accurate and reliable tool for bacterial identification, the present study applied this approach to identify bacterial isolates recovered from the root canals of teeth with chronic apical periodontitis. METHODS: Anaerobic techniques were used for culturing; identification of the isolates was carried out by polymerase chain reaction amplification and sequencing of the V5-V8 region of the 16S rRNA gene. Bacteria were found in all samples. The mean number of taxa per canal was 3.1, ranging from 2 to 8. The median number of cultivable bacterial cells in the root canals was 4.2 x 10(5), ranging from 2.8 x 10(3) to 3.3 x 10(7). Eighty-seven strains belonging to 52 bacterial taxa were identified. The most prevalent taxa were Fusobacterium nucleatum, Porphyromonas gingivalis, Pseudoramibacter alactolyticus, Micromonas micros and streptococci. The following bacterial phyla were represented in this study: Firmicutes (22 taxa, 46% of the identified isolates), Actinobacteria (14 taxa, 25.3% of the isolates), Bacteroidetes (eight taxa, 13.8% of the isolates), Fusobacteria (three taxa, 9.2% of the isolates) and Proteobacteria (five taxa, 5.7% of the isolates). Some of the isolates represented unnamed species not previously cultivated and characterized. In conclusion, our findings using a combined anaerobic culture-molecular identification approach confirmed the polymicrobial nature of primary endodontic infections with dominance of anaerobic bacteria. Notably several bacteria that are difficult or impossible to identify by phenotypic means were identified, including previously uncultivated taxa, cultivated-but-not-yet-characterized taxa and newly named species.

Tunable eletro-optical modulators based on a split-ring resonator.

We present a novel design of an electro-optical modulator setup, consisting of a mechanically tunable cavity which allows the modulation frequency to be varied over a broad range. The design is based on the frequently used geometry of a split-ring resonator which allows for high-efficiency sideband generation. Normally such a configuration has the limitation of a narrow excitation band width ( approximately 20 MHz). Our adjustable setup offers broad-range tunability over several hundred megahertz while still keeping the modulation efficiency. Such a widely tunable modulator may find applications in a variety of experiments in atomic physics.

Performance, digestibility and carcass characteristics of feedlot dairy steers fed diets with different urea levels

The effects of urea levels on feed intake, digestibility and carcass traits of 27 confined cross bred steers weighing 303.25 ± 60.8kg, were evaluated. After weighing, castrating, vaccinating and a period of seven days, three steers were slaughtered at the beginning of the experiment and the remaining 24 were allotted in a completely randomized design to four isonitogenous experimental diets (12 percent of crude protein) and increasing level of urea on the dry matter-basis (0.0; 0.65; 1.30 and 1.65 percent) to replace soybean meal, so that the final content of the experimental diets were approximately 22, 37, 50 and 63 percent of crude protein in the form of NPN. Corn and elephant grass silages were supplied at a 70:30 ratio and the total diet had a 65:35, forage: concentrate ratio on a DM-basis. The urea level did not affect nutrient intake, except for rumen degradable protein (RDP) and total digestible nutrients (TDN) linearly increased in function of diet urea level. The nutrient digestibilities linearly increased except for ether extract and non fiber carbohydrate (NFC). A quadratic effect of diet urea level on daily weight gain and no effect of urea level on carcass traits were observed. Urea can totally replace soybean meal in diets for confined crossed dairy steers allowing gains of 1kg/day. Urea can enhance nutrient digestibility of diets.

Foram avaliados os efeitos dos níveis de uréia sobre o consumo, digestibilidade e características da carcaça de 27 novilhos (303,25 ± 60,80) confinados. Três animais foram abatidos no início do experimento e os 24 restantes foram distribuídos em delineamento inteiramente ao acaso em quatro tratamentos: 0; 0,65; 1,30 e 1,95 por cento de uréia na MS total da dieta, em substituição ao farelo de soja. A dieta final continha em torno de 22, 37, 50 e 63 por cento da PB na forma de compostos nitrogenados não-protéicos. Como volumoso foi utilizada uma mistura de 65 por cento de silagem de milho e silagem de capim-elefante na proporção 70:30, respectivamente. O consumo dos nutrientes não foi afetado pelos tratamentos, com exceção para o consumo de PDR e NDT que aumentaram linearmente. As digestibilidades dos nutrientes apresentaram comportamento linear crescente com exceção das digestibilidades do EE e CNF. Com relação ao desempenho dos animais, houve efeito quadrático dos tratamentos sobre o GMD. Não foi verificado nenhum efeito sobre as características de carcaça avaliadas. A uréia pode substituir completamente o farelo de soja na dieta de novilhos mestiços leiteiros em confinamento, permitindo ganhos de peso próximos a 1kg/dia. O uso de uréia na dieta pode melhorar a digestibilidade dos nutrientes.

A laboratory analysis of gutta-percha-filled area obtained using Thermafil, System B and lateral condensation.

AIM: To determine the percentage of gutta-percha-filled area (PGFA) in the apical third of root canals when filled with either Thermafil, System B or lateral condensation. METHODOLOGY: Sixty extracted human maxillary central incisor teeth were root filled as following: G1: lateral condensation (n = 20), G2: System B (n = 20) and G3: Thermafil system (n = 20). A horizontal section was cut 2 and 4 mm from the apical foramen of each tooth. The samples were prepared for microscopic analysis and photomicrographs of each apical surface were taken at a magnification of 50x. Through digital image analysis, the cross-sectional area of the canal and the gutta-percha was measured. The PGFA was calculated. The PGFA data obtained in the three groups were analysed using a nonparametric Friedman and Wilcoxon signed-rank tests. RESULTS: Significant differences in PGFA were found between the Thermafil System (G3) and both System B (G2) and lateral condensation (G1) (P < 0.01). The greatest PGFA occurred in the Thermafil group. No significant statistical difference was found between System B and lateral condensation (P > 0.05). CONCLUSIONS: The coated carrier gutta-percha system Thermafil produced significantly higher PGFAs than lateral condensation and System B techniques.

Thie expression of an intraspecific aggressive reaction in the face of a stressor agent alters the immune response in rats.

The repercussion on the immune response of the expression of intraspecific aggressiveness in the face of a stressor agent was investigated in rats. Ninety-day-old animals were divided into three groups: the control group (only immunological measurements were performed), the foot-shock (FS) (animals individually receiving FS), and the intraspecific aggressive response (IAR) group (animals receiving FS and presenting IAR). For immunological measurements, blood samples were collected promptly at 7 and 15 days after FS or IAR. The FS reduced the total leukocyte amount presented. However, aggressiveness triggered not only reduction of the leukocytes, but also lymphocyte decrease and neutrophil increase. Moreover, an elevation in total leukocytes associated with an increase in the humoral immune response was also observed one week after IAR. In this study, the expression of intraspecific aggressiveness in the face of a stressor seemed to activate the immune system and to potentiate the antigen specific humoral response.

The expression of an intraspecific aggressive reaction in the face of a stressor agent alters the immune response in rats

A repercussão sobre a resposta imune da expressão da agressividade intra-específica diante de um estressor foi investigada em ratos. Aos 90 dias de vida, os animais foram divididos em três grupos: grupo-controle (foram realizadas apenas mensurações imunológicas), choque nas patas (FS) (os animais receberam FS individualmente) e grupo resposta agressiva intra-específica (IAR) (os animais receberam FS e apresentaram IAR). Para as medições imunológicas, amostras de sangue foram coletadas imediatamente, 7 e 15 dias após FS ou IAR. O FS reduziu a quantidade total de leucócitos. Contudo, a agressividade foi acompanhada, além da redução do número de leucócitos, por diminuição de linfócitos e aumento de neutrófilos. Além disso, também foi observada elevação no número de leucócitos associada a aumento na resposta imune humoral uma semana após as IAR. Neste estudo, a expressão da agressividade intra-específica diante de um estressor parece ativar o sistema imune e potencializar a resposta humoral antígeno específica.

Malnutrition during brain growth spurt alters the effect of fluoxetine on aggressive behavior in adult rats.

Malnutrition effect during the suckling period on aggressive behavior was investigated in adult rats treated and not treated with fluoxetine, a selective serotonin reuptake inhibitor. Sixty-four Wistar male rats were allocated in two groups, according to their mothers' diet during lactation. The well-nourished group was fed by mothers receiving a 23% protein diet; the malnourished one by mothers receiving a 8% protein diet. Following weaning, all rats received the 23% protein diet. On the 90th day after birth, each nutritional group was divided into two subgroups, one receiving a single daily injection of fluoxetine (10 mg/kg) and the other of a saline solution (0.9% NaCl) for 14 days. Treatment with Fluoxetine reduced aggressive response in well-nourished but not in malnourished rats. These findings suggest that the serotoninergic system was affected by malnutrition during the critical period of brain development, and persisted even after a long period of nutritional recovery.

Measurement of the interaction energy near a Feshbach resonance in a 6Li Fermi gas.

We investigate the strongly interacting regime in an optically trapped 6Li Fermi mixture near a Feshbach resonance. The resonance is found at 800(40) G in good agreement with theory. Anisotropic expansion of the gas is interpreted by collisional hydrodynamics. We observe an unexpected and large shift (80 G) between the resonance peak and both the maximum of atom loss and the change of sign of the interaction energy.

A Multiplex-PCR approach to identification of the Brazilian intermediate hosts of Schistosoma mansoni.

Due to difficulties concerning morphological identification of planorbid snails of the genus Biomphalaria, and given a high variation of characters and in the organs with muscular tissue, we designed specific polymerase chain reaction (PCR) primers for Brazilian snail hosts of Schistosoma mansoni from available sequences of internal transcribed spacer 2 (ITS2) of the ribosomal RNA gene. From the previous sequencing of the ITS2 region, one primer was designed to anchor in the 5.8S conserved region and three other species-specific primers in the 28S region, flanking the ITS2 region. These four primers were simultaneously used in the same reaction (Multiplex-PCR), under high stringency conditions. Amplification of the ITS2 region of Biomphalaria snails produced distinct profiles (between 280 and 350 bp) for B. glabrata, B. tenagophila and B. straminea. The present study demonstrates that Multiplex-PCR of ITS2-DNAr showed to be a promising auxiliary tool for the morphological identification of Biomphalaria snails, the intermediate hosts of S. mansoni.

A Multiplex-PCR approach to identification of the Brazilian intermediate hosts of Schistosoma mansoni

Due to difficulties concerning morphological identification of planorbid snails of the genus Biomphalaria, and given a high variation of characters and in the organs with muscular tissue, we designed specific polymerase chain reaction (PCR) primers for Brazilian snail hosts of Schistosoma mansoni from available sequences of internal transcribed spacer 2 (ITS2) of the ribosomal RNA gene. From the previous sequencing of the ITS2 region, one primer was designed to anchor in the 5.8S conserved region and three other species-specific primers in the 28S region, flanking the ITS2 region. These four primers were simultaneously used in the same reaction (Multiplex-PCR), under high stringency conditions. Amplification of the ITS2 region of Biomphalaria snails produced distinct profiles (between 280 and 350 bp) for B. glabrata, B. tenagophila and B. straminea. The present study demonstrates that Multiplex-PCR of ITS2-DNAr showed to be a promising auxiliary tool for the morphological identification of Biomphalaria snails, the intermediate hosts of S. mansoni