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In this paper, we demonstrate that the intrinsic electric field created by a poly(o-methoxyaniline) (POMA) cushion layer hinders the changes in molecular conformation of poly(p-phenylenevinylene) (PPV) in layer-by-layer with dodecylbenzene sulfonic acid (DBS). This was modeled with density functional theory (DFT) calculations where an energy barrier hampered molecular movements of PPV segments when they were subjected to an electric field comparable to that caused by a charged POMA layer. With restricted changes in molecular conformation, the PPV film exhibited Franck-Condon transitions and the photoexcitation spectra resembled the absorption spectra, in contrast to PPV/DBS films deposited directly on glass, with no POMA cushion. Other effects from the POMA cushion were the reduced number of structural defects, confirmed with Raman spectroscopy, and an enhanced PPV emission at high temperatures (300 K) in comparison with the films on bare glass. The positive effects from the POMA cushion may be exploited for enhanced opto-electronic devices, especially as the intrinsic electric field may assist in separating photoexcited electron-hole pairs in photovoltaic devices. [ABSTRACT FROM AUTHOR]

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Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study evaluated the effects of luting length of the post, the resin cement, and cyclic loading on pull-out bond strength of fiberglass posts relined with composite resin in weakened roots. The canals of 80 bovine incisors were endodontically treated and weakened with diamond burs. The teeth were randomly divided into eight groups (n=10) according to the luting procedures of the relined fiberglass post (RFP): In groups 1, 2, 3, and 4, the RFPs were luted with RelyX ARC, and in groups 5, 6, 7, and 8 they were luted with RelyX U200. In groups 1, 3, 5, and 7, the RFPs were luted at a length of 5 mm, and in groups 2, 4, 6, and 8 they were luted at a length of 10 mm. Specimens from groups 3, 4, 7, and 8 were submitted to cyclic loading. Specimens were subjected to a pull-out bond strength test in a universal testing machine. The results (MPa) were analyzed by three-way analysis of variance and the Tukey post hoc test (α=0.05). Six human upper anterior teeth were used to analyze the bond interface by confocal laser scanning microscopy (CLSM). The pull-out bond strength of RFPs luted with RelyX U200 was statistically higher than that of RelyX ARC. Cyclic loading influenced the bond strength only for the luting length of 5 mm. CLSM analysis revealed the formation of resin cement tags for both materials. Luting length is an important factor in retaining RFPs in weakened roots when they are subjected to cyclic loading, and RelyX U200 resulted in greater bond strengths to the root canal in comparison with RelyX ARC. [ABSTRACT FROM AUTHOR]

This work presents tensile mechanical properties, thermal properties, and morphological and structural characteristics of Abaca (Musa textiles) fibers. The results show that the fiber is thermally stable up to 250°C, with a crystalline index higher than 65%. The digital image analysis of the fiber's cross-section revealed that the fibers present a high variability of their average cross-section dimension and shape. The tensile mechanical properties place abaca as high strength - medium modulus fiber, with tensile strength values varying between 511-1051 MPa, and Young's modulus varying between 13.5-29.8 GPa. [ABSTRACT FROM AUTHOR]

The article reports on the study that examines the association of Fas promoter with an increased risk for cervical cancer. The study found no significant difference existed in the distribution of the Fas polymorphisms between the cases and control. It suggests that 670 apoptosis polymorphism in the promoter region of the death receptor Fas is associated with an increased risk of cervical cancer among Brazilian women under 48 years.

Mefenamic acid (H-Mef) is a nonsteroidal anti-inflammatory drug (NSAID). Various adhesive dosage forms of NSAIDs have been developed, which include adhesive tablets, gels, ointments, patches and more recently, polymeric films. The objective of this study was the development of H-Mef adhesive films to be used as a drug-delivery system with different ratios of pectin and calcium chloride dihydrate by the casting technique. The materials were characterized by TG-DSC coupled FTIR, AFM (atomic force microscopy) and spectroscopic techniques. The results provided information about the dehydration, film roughness, surface morphology, thermal decomposition, as well as identification of gaseous products evolved during thermal decomposition. The characterizations indicated the A5 and A6 films functioned well, with 99% H-Mef released within 15 min at pH 5, suggesting these degradable films could be used as a topical delivery system. [ABSTRACT FROM AUTHOR]

Endophytic microorganisms represent promising alternatives for obtaining new drugs of biotechnological importance. In this study, the endophytic species Acremonium cavaraeanum (A1a) isolated from Cocos nucifera was cultivated for the production of secondary metabolites, and its extracts and fractions were evaluated by the dilution method (MIC). The EtOAc extracts and MeOH fractions were tested against Gram-positive and -negative bacteria, and had an MIC of 125 µg/mL when evaluated in the EtOAc extract (EBI). The EtOAc extract (EBII) had an MIC of 62.25 µg/mL for Staphylococcus aureus and an MIC between 125 and 250 µg/mL for Gram-negative bacteria. The methanolic fractions showed activity with MIC between 125 and 250 µg/mL for all bacteria tested. The IGS region of the rDNA repeat unit of genomic DNA was analyzed by PCR/RFLPs, including endonucleases PstI, BamHII, HinfI, and EcoRI. The physical maps showed different restriction sites for the 6 Acremonium sp isolates, and revealed 5 RFLP patterns. The results showed that isolates of the same Acremonium species exhibited variation in this specific region. The sequences of ITS1-5.8S-ITS2 regions were aligned by Clustal W using the neighbor joining method, which grouped the isolates into 5 distinct clusters. This study aimed to evaluate the genetic diversity of A. cavaraeanum crops exhibiting antibacterial activity. The results of this study indicate that different fungal genetic isolates have biotechnological potential for the production of active bio-compounds against several human pathogens.

This report addresses an atypical transmissible venereal tumour in an 8-year-old bitch that was pluriparous and seropositive for leishmaniasis. There were ascites and a serosanguineous discharge from the vulva, but no lesions on the external genital mucosa. An aspirate of the peritoneal fluid showed mononuclear round cells characteristic of transmissible venereal tumour (TVT). Exploratory laparotomy revealed light red, granulomatous structures in the peritoneum, omentum, spleen, liver and uterine horns. Cytological and histopathological tests confirmed the diagnosis of intra-abdominal TVT. Dissemination of the TVT to several organs inside the abdominal cavity probably resulted from immunosuppression caused by leishmaniasis, which favoured the presence and aggressiveness of TVT., (© 2012 Blackwell Verlag GmbH.)

Studies have shown that estrogen replacement therapy and estrogen plus progestin replacement therapy alter serum levels of total, LDL and HDL cholesterol levels. However, HDL cholesterol levels in women vary considerably in response to hormone replacement therapy (HRT). A significant portion of the variability of these levels has been attributed to genetic factors. Therefore, we investigated the influence of estrogen receptor-alpha (ESR1) gene polymorphisms on HDL levels in response to postmenopausal HRT. We performed a prospective cohort study on 54 postmenopausal women who had not used HRT before the study and had no significant general medical illness. HRT consisted of conjugated equine estrogen and medroxyprogesterone acetate continuously for 1 year. The lipoprotein levels were measured from blood samples taken before the start of therapy and after 1 year of HRT. ESR1 polymorphism (MspI C>T, HaeIII C>T, PvuII C>T, and XbaI A>G) frequencies were assayed by restriction fragment length polymorphism. A general linear model was used to describe the relationships between HDL levels and genotypes after adjusting for age. A significant increase in HDL levels was observed after HRT (P = 0.029). Women with the ESR1 PvuII TT genotype showed a statistically significant increase in HDL levels after HRT (P = 0.032). No association was found between other ESR1 polymorphisms and HDL levels. According to our results, the ESR1 PvuII TT genotype was associated with increased levels of HDL after 1 year of HRT.

Radiologic breast density is one of the predictive factors for breast cancer and the extent of the density is directly related to postmenopause. However, some patients have dense breasts even during postmenopause. This condition may be explained by the genes that codify for the proteins involved in the biosynthesis, as well as the activity and metabolism of steroid hormones. They are polymorphic, which could explain the variations of individual hormones and, consequently, breast density. The constant need to find markers that may assist in the primary prevention of breast cancer as well as in selecting high risk patients motived this study. We determined the influence of genetic polymorphism of CYP17 (cytochrome P450c17, the gene involved in steroid hormone biosynthesis), GSTM1 (glutathione S-transferase M1, an enzyme involved in estrogen metabolism) and PROGINS (progesterone receptor), for association with high breast density. One hundred and twenty-three postmenopausal patients who were not on hormone therapy and had no clinical or mammographic breast alterations were included in the present study. The results of this study reveal that there was no association between dense breasts and CYP17 or GSTM1. There was a trend, which was not statistically significant (P = 0.084), towards the association between PROGINS polymorphism and dense breasts. However, multivariate logistic regression showed that wild-type PROGINS and mutated CYP17, taken together, resulted in a 4.87 times higher chance of having dense breasts (P = 0.030). In conclusion, in the present study, we were able to identify an association among polymorphisms, involved in estradiol biosyntheses as well as progesterone response, and radiological mammary density.

Breast cancer is a common disease in Western societies, with an incidence of 46.31/100,000 women/year in Brazil. The tumor suppressor gene TP53 is one of the most studied genes regarding the presence of mutations. Indeed, 50% of all tumors are known to exhibit changes in the TP53 nucleotide sequence due to carcinogenic processes. As to the presence of polymorphism, the TP53 gene is polymorphic at the nucleotide residue 347 (codon 72). In the current study, we examine if this polymorphism is associated with the clinicopathological parameters of breast cancer patients in a Brazilian population. One hundred and thirteen patients with breast cancer were included. The polymorphic region of the TP53 gene was PCR-amplified from genomic DNA obtained from buccal cells. Specific primers for the Pro and Arg allele were used. Correlations of polymorphism with age, staging, nuclear grade, lymph node status, estrogen receptor status and lymphatic and/or blood vessel invasion were evaluated. Statistical analysis was performed using the Fisher's exact test. The frequency of p53 Arg/Arg was 57% and of the heterozygous allele Arg/Pro it was 39%. There was no correlation between polymorphism and clinicopathological parameters. According to our results, the TP53 polymorphism, at the 347 residue, is not associated with any clinicopathological findings of patients with breast cancer.

Objective: To analyze the participation of glutathione-S-transferase (GST) M1 and T1 polymorphisms associated or not with protein p53 polymorphism at codon 72 and in the presence of HPV in the carcinogenesis of uterine cervix adenocarcinoma., Methods: Forty-three samples of uterine cervix adenocarcinoma were studied and 86 samples of endocervical cells of women without tumors formed the control group. The presence of HPV was determined in order to genotype the isoforms of p53 at codon 72, GSTM1, GSTM1*0, GSTT1 and GSTT1*0 which were evaluated by the PCR method., Results: HPV was present in 97.67% of the adenocarcinoma cases and in 31.40% of the control group. Statistical analysis showed differences (p = 0.001) and an OR of 113.3 (CI 95%: 13.67-947.14). GSTT1 and GSTT1*0 analysis showed a significant difference between the groups (p = 0.001) with an OR of 4.58 (CI 95%: 2.041-10.28) (p < 0.001) for the presence of GSTT1*0. When it was associated with HPV OR was 6.6 (CI 95%: 0.04-0.50). Analyses of p53 and GSTM1 and GSTM1*0 either alone or associated with HPV were not significant., Conclusion: The presence of GSTT1*0 increased the risk for uterine cervix adenocarcinoma development while the allele GSTT1 had a protective action. The other isoforms did not appear to participate in the carcinogenesis of uterine cervix adenocarcinoma.

Purpose: To study the relationship between topoisomerase IIalpha, active caspase-3 expressions and HPV DNA in uterine cervices with low-grade squamous intraepithelial lesions (LSIL)., Methods: Forty women with LSIL and 32 without cervical neoplasia diagnosed through cytologic and histopathologic examination were evaluated regarding topoisomerase IIalpha and active caspase-3 expressions and HPV DNA detection using PCR (GP5/GP6) in cervicovaginal smears., Results: The mean percentage of cells immunomarked by topoisomerase in the group with LSIL was 11.62% while in the control it was 4.13% (p < 0.0001). In the presence of HPV DNA, topoisomerase expression was higher in the group with productive viral infection than in nonneoplastic tissue (p = 0.004). Caspase-3 expression was observed in 17 patients with LSIL (42.5%) and in five without cervical neoplasia (15.63%)., Conclusion: The use of topoisomerase IIalpha and active caspase-3 in cervical biopsies may help to define the prognosis of HPV cervical infection.

Recent data implicate that cytokine gene polymorphisms are important in pathogenesis of various neoplastic and nonneoplastic human diseases, and it was recently suggested that polymorphisms in interleukin (IL)-6 might increase the risk of gynecological malignancies, including cervical carcinomas. The aim of this case-control study is to compare the IL-6 polymorphisms in cervical cancer patients and healthy controls and to assess whether any of these polymorphisms would increase the risk of developing cervical cancer. The material in this case-control study consists of 56 patients with cervical carcinoma and 253 population-based control subjects, all ethnic Brazilian women. Control subjects were cancer-free women, following a negative cervical cytology and colposcopy. IL-6 genotyping was performed using a polymerase chain reaction-based restriction fragment length polymorphism. Distribution of the GG, GC, and CC genotypes in cases and controls was significantly different (P= 0.033). Compared with the GG genotype as reference, the adjusted odds ratio for the combined GC and CC genotypes in cancer patients was 1.90 (95% confidence interval, 1.1-3.4). These data suggest that women carrying at least one C genotype in their IL-6 promoter region (-174G-->C) are at higher risk of developing cervical cancer.

Purpose of Investigation: To analyze the results of a statewide screening program inaugurated in 2002 in Mato Grosso do Sul,, Methods: Retrospective audit of the screening results of 8,477 pregnant women for 11 diseases in 19 tests. Local health centers of the Brazilian Unified System of Health/State Program of Pregnant Protection (SUS/PEPG) and central reference processing laboratories, both in and out of state were involved. Pregnant women were referred to the program by medical staff principally at local health centers, between November 2002 and February 2003. Primary screening with filter-paper blood samples was carried out with positives being resampled and sera appropriately tested., Results: The detailed test results are given below; the most frequent diseases serodiagnosed were hepatitis B, syphilis, HIV and Chagas' disease. One case of maternal phenylketonouria (PKU) was encountered., Conclusion: The diagnosis of 11 diseases of importance for mothers and their offspring provides an epidemiological profile of Brazil, but must be matched by opportunities to elaborate new control strategies and improve health care during pregnancy.