DNA repair gene polymorphism is associated with the genetic basis of atherosclerotic coronary artery disease

Background: Atherosclerotic coronary artery disease (CAD) is a multifactorial process that appears to be caused by the interaction of environmental risk factors with multiple predisposing genes. It is nowadays accepted that increased levels of DNA damage induced by xenobiotics play an important role in the early phases of atherogenesis. Therefore, in this study, we focus on determining whether genetic variations in xenobiotic-metabolizing [glutathione-S-transferase theta 1 (GSTT1), glutathione-S-transferase mu 1 (GSTM1), cytochrome P450 IIEI (CYP2E1)] and DNA repair [X-ray cross-complementing group 1 (XRCC1)] genes might be associated with increased risk for CAD. Methods: A case-control study was conducted with 400 individuals who underwent subjected to coronary angiography. A total of 299 were patients diagnosed with effective coronary atherosclerosis (case group; >20% obstructive lesion), and 101 (control group) were individuals diagnosed as negative for CAD (<20% obstructive lesions). The polymorphism identifications for GSTM1 and GSTT1, and for CYP2E1 and XRCC1 genes were performed by polymerase chain reaction (PCR) amplification and by PCR-RFLP, respectively. Results and conclusions: The XRCC1 homozygous wild-type genotype Arg/Arg for codon 399 was statistically less pronounced in the case subjects (21.4%) than in controls (38.5%); individuals with the variant XRCC1 genotype had a 2.3-fold increased risk for coronary atherosclerosis than individuals with the wild-type genotype (OR=2.3, 95% CI=1.13-4.69). Conversely, no association between GSTM1, GSTT1, and CYP2E1gene polymorphisms and coronary atherosclerosis was detected. The results provide evidence of the role of DNA damage and repair in cardiovascular disease. © 2011 Elsevier Inc. All rights reserved.

Evolução metamórfica e termobarometria das rochas metamáficas/metabásicas da região de Pontalina - GO

At the Pontalina region, the Magmatic Arc of Goiás is constituted by orthogneisses, metasediments, metaultramafics and metamafic/metabasics, geochemically related to island arcs. Mineral assemblages related to metamorphic peak observed in the study area are typically of the amphibolite facies and were generated before or during the initial stage of the development of the main foliation (S n). Thermobarometric data show the P and T conditions for the amphibole + plagioclase and plagioclase + garnet + amphibole assemblages in the metamafic/metabasic rocks correspond to amphibolite facies (medium to upper grade), and plot in the kyanite stability field. The results indicate that the metamorphic peak (M1) in the amphibolite facies (medium up to upper grade) reached temperatures slightly higher than 700°C, not exceeding 775°C, under conditions of medium pressure (∼10 kbar). Thermobarometric and petrographic data, related to the metamorphism, indicate a clockwise P-T path for the surrounding rocks.

Micromechanics of dentin/adhesive interface in function of dentin depth: 3d finite element analysis

Objectives: The aim of this study was to analyze the stress distribution on dentin/adhesive interface (d/a) through a 3-D finite element analysis (FEA) varying the number and diameter of the dentin tubules orifice according to dentin depth, keeping hybrid layer (HL) thickness and TAǴs length constant. Materials and Methods: 3 models were built through the SolidWorks software: SD - specimen simulating superficial dentin (41 x 41 x 82 μm), with a 3 μm thick HL, a 17 μm length Tag, and 8 tubules with a 0.9 μm diameter restored with composite resin. MD - similar to M1 with 12 tubules with a 1.2 μm diameter, simulating medium dentin. DD - similar to M1 with 16 tubules with a 2.5 μm diameter, simulating deep dentin. Other two models were built in order to keep the diameter constant in 2.5 μm: MS - similar to SD with 8 tubules; and MM - similar to MD with 12 tubules. The boundary condition was applied to the base surface of each specimen. Tensile load (0.03N) was performed on the composite resin top surface. Stress field (maximum principal stress in tension - σMAX) was performed using Ansys Wokbench 10.0. Results: The peak of σMAX (MPa) were similar between SD (110) and MD (106), and higher for DD (134). The stress distribution pathway was similar for all models, starting from peritubular dentin to adhesive layer, intertubular dentin and hybrid layer. The peak of σMAX (MPa) for those structures was, respectively: 134 (DD), 56.9 (SD), 45.5 (DD), and 36.7 (MD). Conclusions: The number of dentin tubules had no influence in the σMAX at the dentin/adhesive interface. Peritubular and intertubular dentin showed higher stress with the bigger dentin tubules orifice condition. The σMAX in the hybrid layer and adhesive layer were going down from superficial dentin to deeper dentin. In a failure scenario, the hybrid layer in contact with peritubular dentin and adhesive layer is the first region for breaking the adhesion. © 2011 Nova Science Publishers, Inc.

Osseointegration of implants with dendrimers surface characteristics installed conventionally or with Piezosurgery®. A comparative study in the dog

Aim: The first aim of the present experiment was to compare bone healing at implants installed in recipient sites prepared with conventional drills or a piezoelectric device. The second aim was to compare implant osseointegration onto surfaces with and without dendrimers coatings. Material and Methods: Six Beagles dogs were used in this study. Five implants with two different surfaces, three with a ZirTi® surface (zirconia sand blasted, acid etched), and two with a ZirTi®-modified surface with dendrimers of phosphoserine and polylysine were installed in the right side of the mandible. In the most anterior region (P2, P3), two recipient sites were prepared with drills, and one implant ZirTi® surface and one coated with dendrimers implants were installed at random. In the posterior region (P4 and M1), three recipient sites were randomly prepared: two sites with a Piezosurgery® instrument and one site with drill and two ZirTi® surface and one coated with dendrimers implants installed. Three months after the surgery, the animals were sacrificed for histological analysis. Results: No complications occurred during the healing period. Three implants were found not integrated and were excluded from analysis. However, n = 6 was obtained. The distance IS-B at the buccal aspect was 2.2 ± 0.8 and 1.8 ± 0.5 mm, while IS-C was 1.5 ± 0.9 and 1.4 ± 0.6 mm at the Piezosurgery® and drill groups, respectively. Similar values were obtained between the dendrimers-coated and ZirTi® surface implants. The BIC% values were higher at the drill (72%) compared to the Piezosurgery® (67%) sites. The BIC% were also found to be higher at the ZirTi® (74%) compared to the dendrimers-coated (65%) implants, the difference being statistically significant. Conclusion: This study has revealed that oral implants may osseointegrate equally well irrespective of whether their bed was prepared utilizing conventional drills with abundant cooling or Piezosurgery®. Moreover, the surface coating of implants with dendrimers phosphoserine and polylysine did not improve osseointegration. © 2012 John Wiley & Sons A/S.

Improvement of Matrinxã, Brycon amazonicus, Larviculture by Exposing Eggs to Triiodothyronine

This work evaluated the effect of triiodothyronine (T3) on larviculture of matrinxã, Brycon amazonicus. Oocytes of three females were pooled, fertilized with pooled semen of two males and separated in four batches that were immersed in triiodothyronine solutions as follows: M1 (control - water); M2 (0.01mg/L T3); M3 (0.05mg/L T3); and M4 (0.1mg/L T3). Triiodothyronine did not affect fertilization rate and number of hatched larvae. Weight of hatched larvae was significantly higher in treatments M3 and M4, as well as among larvae sampled at Day 12 in all treatments. After 12d of rearing, biomass gain was higher in the hormone treatments (M1 688±569mg; M2 2436±562mg; M3 3572±569mg; and M4 4129±770mg). In general, coefficients of variation of weight (CVw) and length (CVl) did not differ among treatments and cannibalism was registered between 36 and 72hours post-hatching (h.p.h.) without differences among treatments. Larval survival increased in the hormone treatments (M1 26.5%; M2 37.6%; M3 40.6%; and M4 40.8%). The results indicate that the immersion of matrinxã eggs in triiodothyronine can promote beneficial effects to its larviculture and indicate promising perspectives for culture of this tropical species. © by the World Aquaculture Society 2013.

Assessment of the chemopreventive effect of casearin B, a clerodane diterpene extracted from Casearia sylvestris (Salicaceae)

Studies have shown that Casearia sylvestris compounds protect DNA from damage both in vitro and in vivo. Complementarily, the aim of the present study was to assess the chemopreventive effect of casearin B (CASB) against DNA damage using the Ames test, the comet assay and the DCFDA antioxidant assay. The genotoxicity was assessed by the comet assay in HepG2 cells. CASB was genotoxic at concentrations higher than 0.30μM when incubated with the FPG (formamidopyrimidine-DNA glycosylase) enzyme. For the antigenotoxicity comet assay, CASB protected the DNA from damage caused by H2O2 in the HepG2 cell line in concentrations above 0.04μM with post-treatment, and above 0.08μM with pre-treatment. CASB was not mutagenic (Ames test) in TA 98 and TA 102. In the antimutagenicity assays, the compound was a strong inhibitor against aflatoxin B1 (AFB) in TA 98 (>88.8%), whereas it was moderate (42.7-59.4%) inhibitor against mytomicin C (MMC) in TA 102. Additionally, in the antioxidant assay using DCFDA, CASB reduced reactive oxygen species (ROS) generated by H2O2. In conclusion, CASB was genotoxic to HepG2 cells at high concentrations; was protective of DNA at low concentrations, as shown by the Ames test and comet assay; and was also antioxidant. © 2012 Elsevier Ltd.

Tumor-associated macrophages and the profile of inflammatory cytokines in oral squamous cell carcinoma

Objective: To evaluate and characterize macrophage populations (M1/M2) in the tumor microenvironment of oral cavity squamous cell carcinoma (OCSCC). The relationship between macrophages and clinicopathological factors, such as survival data, lymph node metastasis, tumoral proliferation, and WHO histological grading are also analyzed. Materials and methods: The samples consisted of surgically excised specimens from patients with non-metastatic and metastatic OCSCC and normal oral mucosa (control). Immunohistochemistry, flow cytometry, and qRT-PCR were used to evaluate macrophage populations and the expression of pro- (IL-12, IL-23, and INF-γ) and anti-inflammatory (IL-10 and TGF-β) cytokines. The level required for statistical significance was defined as p < 0.05. Results: The data showed a predominance of M2 phenotype (high percentage of IL-10+TGF-β+) macrophages in the tumor microenvironment of OCSCC. A higher percentage of macrophages expressing TGF-β was seen in the OCSCC group when compared with healthy individuals. The assessment of mRNA expression also presented a greater expression of anti-inflammatory cytokines TGFβ and IL10 in OCSCC when compared with the control group. The percentage of macrophages, demonstrated by immunohistochemistry, was significantly higher in the metastatic OCSCC group than in the non-metastatic and control groups. The log-rank test also showed that the mean survival time for patients with high levels of macrophages was less (44 months) when compared with patients with a low percentage of such cells (93 months). Conclusion: A predominance of the M2 phenotype in the tumor microenvironment of OCSCC could contribute to local immunosuppression, via TGF-β production, and consequently greater lymph node involvement and reduced patient survival time. © 2012 Elsevier Ltd. All rights reserved.

Effect of thermal cycling on denture base and autopolymerizing reline resins

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Nephrocalcinosis induced by hyperoxaluria in rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The Predominance of Alternatively Activated Macrophages Following Challenge with Cell Wall Peptide-Polysaccharide After Prior Infection with Sporothrix schenckii

Sporotrichosis is a subcutaneous mycosis that is caused by the dimorphic fungus Sporothrix schenckii. This disease generally occurs within the skin and subcutaneous tissues, causing lesions that can spread through adjacent lymphatic vessels and sometimes leading to systemic diseases in immunocompromised patients. Macrophages are crucial for proper immune responses against a variety of pathogens. Furthermore, macrophages can play different roles in response to different microorganisms and forms of activation, and they can be divided into classic or alternatively activated populations, as also known as M1 and M2 macrophages. M1 cells can lead to tissue injury and contribute to pathogenesis, whereas M2 cells promote angiogenesis, tissue remodeling, and repair. The aim of this study was to investigate the roles of M1 and M2 macrophages in a sporotrichosis model. Toward this end, we performed phenotyping of peritoneal exudate cells and evaluated the concomitant production of several immunomediators, including IL-12, IL-10, TGF-β, nitric oxide, and arginase-I activity, which were stimulated ex vivo with cell wall peptide-polysaccharide. Our results showed the predominance of the M2 macrophage population, indicated by peaks of arginase-I activity as well as IL-10 and TGF-β production during the 6th and 8th weeks after infection. These results were consistent with cellular phenotyping that revealed increases in CD206-positive cells over this period. This is the first report of the participation of M2 macrophages in sporotrichosis infections. © 2013 Springer Science+Business Media Dordrecht.

Estrogenic and chemopreventive activities of xanthones and flavones of Syngonanthus (Eriocaulaceae)

The possible benefits of some bioactive flavones and xanthones present in plants of the genus Syngonanthus prompted us to screen them for estrogenic activity. However, scientific research has shown that such substances may have undesirable properties, such as mutagenicity, carcinogenicity and toxicity, which restrict their use as therapeutic agents. Hence, the aim of this study was to assess the estrogenicity and mutagenic and antimutagenic properties. We used recombinant yeast assay (RYA), with the strain BY4741 of Saccharomyces cerevisiae, and Ames test, with strains TA100, TA98, TA97a and TA102 of Salmonella typhimirium, to evaluate estrogenicity, mutagenicity and antimutagenicity of methanolic extracts of Syngonanthus dealbatus (S.d.), Syngonanthus macrolepsis (S.m.), Syngonanthus nitens (S.n.) and Syngonanthus suberosus (S.s.), and of 9 compounds isolated from them (1 = luteolin, 2 = mix of A-1,3,6-trihydroxy-2-methoxyxanthone and B-1,3,6-trihydroxy-2,5- dimethoxyxanthone, 3 = 1,5,7-trihydroxy-3,6-dimethoxyxanthone, 4 = 1,3,6,8-tetrahydroxy-2,5-dimethoxyxanthone, 5 = 1,3,6,8-tetrahydroxy-5- methoxyxanthone, 6 = 7-methoxyluteolin-8-C-β-glucopyranoside, 7 = 7-methoxyluteolin-6-C-β-glucopyranoside, 8 = 7,3′-dimethoxyluteolin- 6-C-β-glucopyranoside and 9 = 6-hydroxyluteolin). The results indicated the estrogenic potential of the S. nitens methanol extract and four of its isolated xanthones, which exhibited, respectively, 14.74 ± 1.63 nM; 19.54 ± 6.61; 7.20 ± 0.37; 6.71 ± 1.02 e 10.01 ± 4.26 nM of estradiol-equivalents (EEQ). None of the extracts or isolated compounds showed mutagenicity in any of the test strains and all of them showed antimutagenic potential, in particular preventing mutations caused by aflatoxin B1 (AFB1) and benzo[a]pyrene (B[a]P). The results show that the xanthones, only isolated from the methanol extract of S. nitens capitula, probably were the responsible for its estrogenic activity and could be useful as phytoestrogens, providing a new opportunity to develop hormonal agents. In addition, flavones and xanthones could also be used as a new antimutagenic agent. Since, the mutagens are involved in the initiation and promotion of several human diseases, including cancer, the significance of novel bioactive phytocompounds in counteracting these pro-mutagenic and carcinogenic effects is now gaining credence. © 2013 Elsevier Inc. All rights reserved.

The relationships between scrotal surface temperature, age and sperm quality in stallions

In horses, spermatogenesis normally occurs at an average intratesticular temperature of 35. °C; therefore, mechanisms for testicular thermoregulation are essential. Measuring the scrotal surface temperature by thermography is one of the methodologies used to evaluate the effectiveness of testicular thermoregulation. The objective of this study was to determine the relationship between the control of scrotal surface temperature and sperm quality in horses of different ages. In total, 24 Quarter Horse stallions were divided into three groups: YS (young stallions), AS (adult stallions) and OS (old stallions). Initially, we calculated the testicular volume (TV) and evaluated various aspects of the semen (sperm kinetics, plasma membrane integrity and sperm morphology) for all the animals. We also evaluated rectal temperature (RT), body surface temperature (BST,) and average scrotal surface temperature in the testicular region (SST) before (M0) and after sun exposure (M1). Differences were observed (p<0.05) between the RT and BST before and after sun exposure in all three groups. However, there were no differences (p>0.05) in the SST values at these two time points, thus demonstrating the efficiency of the mechanisms for testicular thermoregulation. The SST was similar (p>0.05) among all three groups. Based on these results, we conclude that fertile stallions of different age groups are able to maintain SST and measuring the heat radiating from the scrotum using a digital infrared thermographer. We can also conclude that measuring the heat radiating from the scrotum using a digital infrared thermographer is a practical and efficient tool for monitoring SST in horses. © 2013 Elsevier B.V.

Avaliação da qualidade de vida em pacientes portadores de câncer de esôfago submetidos à inserção de stent esofágico auto-expansível

Pós-graduação em Bases Gerais da Cirurgia - FMB

Consulta de enfermagem como instrumento de avaliação do protocolo assistencial de gastrostomia endóscópica percutânea

Pós-graduação em Bases Gerais da Cirurgia - FMB

Análise da biocompatibilidade de cones de biovidro e biovitrocerâmico em cavidade eviscerada de coelho

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)