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Following the appearance of several antimicrobial agents to control the spread of infections, two major challenges have emerged: (i) the occurrence and blowout of multiresistant bacteria and the increase of chronic diseases and (ii) difficult-to-eradicate infections. In this study, we tested five benzoylthiourea derivatives for their ability to inhibit and stop bacterial growth and evaluated the possible influence of 1,2,4-triazolyl-benzoylthiourea derivative 4 on the formation and eradication of Staphylococcus aureus biofilms. Benzoylthiourea derivatives 4, 6, 10, 11 and 13 were obtained in one or two steps with low cost and subjected to tests to identify their minimum inhibitory concentration (MIC) and minimum bactericidal concentration. In vitro tests were also performed to assess their effects on biofilm formation and in preformed biofilms and scanning electron microscopy was used to visualize the effects on biofilm formation. The 1,2,4-triazolyl-benzoylthiourea derivative 4 showed bacteriostatic activity against the S. aureus HU25 clinical strain with an MIC of 16 µg ml-1 , which is below the toxic concentration (at 2500 µg ml-1 , 62·25% of the cells remained viable). Compound 4 also effectively prevented biofilm formation at the three subinhibitory concentrations tested (1/2 MIC, 1/4 MIC and 1/8 MIC) as confirmed by scanning electron microscopy. For breakdown of formed biofilms, the main influence was at a subinhibitory concentration (1/2 MIC). These findings make compound 4 a strong candidate for studies on the development of new antimicrobial and antibiofilm agents.

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The ABCB1 gene encodes the P-glycoprotein (P-gp) which regulates distribution and bioavailability of many endogenous and exogenous substrates, acting as a cellular mechanism of protection against these substances. Some studies have shown evidence that P-gp is related to carcinogenesis. In this study, we performed PCR and direct sequencing of ABCB1 exons 9 and 26 in 47 tissue DNA samples from canine mammary tumors. A statistically significant correlation between distinct canine breeds and the frequency of ABCB1 polymorphisms (c.985T > A and c.3442A > G SNP in ABCB1exons 9 and 26, respectively) was observed (P = 0.0015). In contrast, the TNM clinical staging, age, histological type and grade, as well as other histopathological characteristics, did not present statistically significant difference in relation to one or both SNP found in exons 9 and 26. These findings raise questions about the role of the canine ABCB1 polymorphisms in the development of mammary tumors, since the Poodle breed, which is the most common dog breed affected by mammary tumors in Brazil, presented the highest frequency of these variants. Notwithstanding, additional studies comprising a number of samples expressing the ABCB1 gene from healthy dogs, with advanced age and from different breeds, will be necessary to confirm the association of ABCB1polymorphisms and the development of mammary tumors.

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The canine BRCA2 is a tumor supressor gene which encodes the BRCA2 protein, involved in DNA repair through interaction with the RAD51 recombinase. This process is mediated by eigth BRC repeats that are encoded by BRCA2 exon 11. Two variants corresponding to human mutations in human BRC3 repeat have been reported in canine BRC3 repeat. In addition, other variants have also been described in canine BRCA2 exon 11. Considering the importance of polymorphisms in human BRCA2 to breast cancer development, this study aimed to investigate the frequency of variants in BRCA2 exon 11 in 48 blood and tissue DNA samples from bitches with canine mammary tumors (CMT), as well as, to analyze tumor stage and histopathological features. Seven Single Nucleotide Polymorphisms (SNPs) were identified, three of which were evaluated as possibily or probably deleterious variant. Interestingly, almost all the 22 mammary tumors (except one) which presented a clinical staging equal to or greater than III carried at least one mutant allele of these three variants. Besides that, no statistically significant correlation was observed between any of the reported SNPs in heterozygosis or homozygosis and either dogs data (such as breed, age or disease stage) or mammary tumors histopathological characteristics. A total of 97.9% of bitches had one to three polymorphisms of the seven identified in this study, which suggests a possibly correlation between the canine BRCA2 exon 11 polymorphisms and mammary carcinogenesis.

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O objetivo deste trabalho é avaliar o uso da túnica albugínea suína na cistoplastia em ratos, avaliando funcionalidade, capacidade de reparação do órgão e possibilidades de complicações. Foram selecionados 30 ratos Wistar, machos, de seis meses de idade, divididos em: um grupo teste (TA), em que os animais receberam o enxerto de túnica albugínea suína após a cistectomia parcial e um grupo controle (C), em que os animais sofreram somente a cistectomia parcial. Os animais pertencentes a ambos os grupos foram divididos igualmente em subgrupos de cinco animais cada, que sofreram eutanásia em sete, 28 e 42 dias de pós-operatório. Foi realizada uma análise macroscópica e, posteriormente, uma análise histopatológica da região da ferida cirúrgica. Aos sete e 28 dias, os animais pertencentes ao grupo C e ao grupo TA apresentaram urotelização, regeneração da lâmina própria e da musculatura, porém o grupo TA apresentou menores sinais inflamatórios e maior organização tecidual, principalmente com relação à formação das fibras musculares. Aos 42 dias de pós-operatório, ambos os grupos já apresentavam características histológicas normais. Concluiu-se que o enxerto de túnica albugínea suína obteve sucesso na regeneração da bexiga de ratos, mantendo a funcionalidade do órgão, sem rejeição, e favorecendo a migração celular.(AU)

The aim of this study is to evaluate porcine tunica albuginea as a graft for cystoplasty in rats, regarding bladder function, capacity and possible complications. 30 male Wistar rats with six monthes of age have been selected and separated into two different groups: A test group (TA) in which the animals received a tunica albuginea graft after partial cystectomy and a control group (C) in which partial cystectomy was performed, followed by bladder suture. In each group the animals were euthanized at seven, 28 and 42 days after surgery. Macroscopic and Histological analysis have been performed. At seven and 28 days after surgery the samples from both groups had urothelial lining upon a lamina propria and smooth muscle fibers in regeneration process. However, the TA group showed less inflammatory signs and more organized structure, mainly regarding the smooth muscle formation. At 42 days after surgery all groups showed a bladder wall structure qualitatively identical to the normal tissue. We could conclude that tunica albuginea graft is able to maintain bladder function and support cellular migration without any kind of rejection.(AU)

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