Adriane Pozzobon

Estrogen receptor-, bcl-2 and c-myc gene expression in fibroadenomas and adjacent normal breast: Association with nodule size, hormonal and reproductive features

Fibroadenomas are the most common benign lump in females. The study of gene alterations and/or deregulation in reproductive years may help explain hormonal physiological processes involved in nodule development and evolution. The objective was to compare ER-alpha, c-myc, and bcl-2 gene expression in breast fibroadenomas and in normal tissue and evaluate menstrual cycle, parity, and oral contraceptive influences. Fifty-seven premenopausal women (14-49 years) undergoing surgical removal of fibroadenomas were selected. Samples from fibroadenomas and circumjacent normal tissue were obtained for RT-PCR paired analysis. Patients were divided in groups according to menstrual cycle, use of contraceptives and parity. Tissue from 32 patients was adequate for RT-PCR. Paired analysis showed higher expression of ER-alpha (P=0.012) and bcl-2 (P=0.001) in fibroadenomas than in normal breast, while c-myc presented a similar expression (P=0.655). ER-alpha was higher in fibroadenomas of patients in follicular phase versus contraceptive users and normal tissue (P=0.003); bcl-2 was higher in fibroadenomas of patients in luteal phase than in the normal samples from all groups (P=0.007). c-myc did not differ according to menstrual cycle, but was higher in fibroadenomas>3 cm versus<3 cm (P=0.015) and in nulliparous women (P=0.04). A positive correlation between c-myc levels and fibroadenoma diameter was demonstrated (r=0.536; P=0.007). Nulliparous mean nodule diameter was superior than parous women (P=0.008). In conclusion, the expression of ER-alpha, bcl-2 and c-myc depends on hormonal and reproductive factors, with a possible contribution to lump formation and evolution.

Androgen-Dependent Expression of c-jun and c-fos in Human Non-Transformed Epithelial Prostatic Cells: Association with Cell Proliferation

Objective: To assess the effect of dihydrotestosterone (DHT) on the gene expression of c-fos and c-jun and on the proliferation of human non-transformed epithelial prostatic (HNTEP) cells. Methods: Cell proliferation (MTT) and c-fos and c-jun mRNA expression (RT-PCR) were determined in cells treated with DHT (10–8, 10–10, and 10–13M) or with control medium. Results: DHT 10–13 M had a significant stimulatory effect on cell proliferation (p < 0.05) and c-fos and c-jun gene expression when compared to cells treated with higher concentrations of this hormone (10–10 and 10–8M) or with the control group. Conclusions: Our data demonstrate that the increase in c-fos and c-jun expression and cell growth in HNTEP cells is maximal with the lowest DHT concentration (10–13M). These proto-oncogenes may play a role in the control of hormone responsiveness and cell proliferation in HNTEP cells.

Characterization of technological and probiotic properties of indigenous Lactobacillus spp. from south Brazil

In this study, we isolated Lactobacillus spp. from bovine raw milk and artisanal cheese from southern Brazil, and evaluated their technological and probiotic potential to select new isolates for producing healthy fermented dairy foods with differentiated tastes and flavours. We obtained 48 new lactobacilli isolates, which were isolated from raw milk (38) and cheese (10). These bacterial isolates were closely related with ten species: Lactobacillus paracasei (50% of the isolates), L. parabuchneri (15%), L. pentosus (13%), L. zeae (4%), L. plantarum (4%), L. otakiensis (4%), L. casei (4%), L. harbinensis (2%), L. diolivorans (2%), and L. rhamnosus (2%). Isolates CH112 and CH131 showed the greatest acidification potential, reducing the pH of milk to below 5.3 after incubation for 6xa0h at 32xa0°C. Considering proteolytic activity and diacetyl production, isolates ML88a, ML04, and ML12 showed the most promising results. Isolate ML12 showed 100% survival rate when inoculated in gastric juice at pH 2.5. The evaluation of antibacterial activity of the lactobacilli showed that the pathogens Listeria monocytogenes, Staphylococcus aureus, Salmonella enteritidis, and Salmonella Typhimurium were strongly inhibited by the pure lactobacilli cultures. Five Lactobacillus isolates (ML01, ML04, ML12, ML88, and CH139) showed both technological and probiotic characteristics. Principal Component Analysis (PCA) was used to investigate correlations among technological and probiotic characteristics, and identified new promising lactobacilli isolates for exploring their characteristics. This study reveals the importance of selecting new microorganisms with potential applicability in the food industry for developing functional foods with differentiated aromas and flavours.

Prevalence and genotyping of pathogenic Escherichia coli on carcasses of pigs slaughtered in commercial slaughterhouses in southern region of Brazil

The pork is an important source of animal protein for the world, however it’s associated to food poisoning outbreaks. One of the causes of such episodes is the contamination by Escherichia coli, that can be found in the intestinal tract and environment of pigs slaughtered for production of “in natura” and industrialized meat. In the context of food safety, outbreaks of Escherichia coli that producing Shiga toxin (STEC) are the best documented. In the context of food security, outbreaks of Escherichia coli Shiga toxin-producing (STEC) are well documented. However, there are few data about the occurrence of this pathogen in swine and pork meat in Brazil. The aim of this study was to quantify contamination by E. coli of swine carcass slaughtered in abattoirs located in the Southern region of Brazil and to identify by PCR the presence of shiga toxin and intimin producing E. coli. Swabs of 272 swine carcasses were performed in slaughterhouses of RS, SC and PR States. A total of 25 carcasses were contaminated, 20 at RS and 5 at PR. DNA was extracted of positive samples for genotyping by PCR. None of the samples were positive for stx1 gene, however 13 samples were positive for the eaeA gene in different parts of the carcass. The PCR technique can be a useful tool for screening microbiological contamination through slaughter, helping to reduce the occurrence of foodborne infections outbreaks caused by E. coli and other microorganisms.

Polymorphisms in SNP CGIL4: association stuty on the phenotype of clinical mastitis resistance in Holstein cows

Bovine mastitis is the most important udder pathology and have a significant economic impact in the dairy industry. Its etiology is associated to problems with health and milking management. However, there are animals with resistance or susceptibility to mastitis, even when environmental factors are controlled. Recently, some molecular markers were associated to the phenotype of resistance to mastitis. The present study aims to verify if, based on clinical history of cows of second and third lactation, the SNP CGIL4 is associated to the phenotype of resistance to mastitis in Holstein cows in a herd in southern Brazil. Genomic DNA was obtained from blood samples of 160 Holstein cows (second and third lactation) from dairy herds from Rio Grande do Sul state, Brazil. Phenotype of resistance or susceptibility to clinical mastitis was defined based on animal’s clinical history, and the animal was classified as susceptible if presented at least 3 episodes of clinical mastitis during the last lactation. The identification of the CGIL4 SNP was performed using a PCR-RFLP. The association between genotipes and phenotipes was acessed by the χ 2 test. To detect polymorphism, Polymerase Chain Reaction (PCR) was performed using a touch-down PCR reaction producing an amplicon of 399 bp. The Restriction Fragment Length

DETECÇÃO DE LISTERIA MONOCYTOGENES PELA TÉCNICA DA REAÇÃO EM CADEIA DA POLIMERASE (PCR) EM AMOSTRAS DE LEITE BOVINO IN NATURA

Considering the possible incidence of Listeria monocytogenes in raw foods and their pathogenicity and health risk, this study aimed to compare techniques for extraction of bacterial DNA from milk samples and investigate the presence of L. monocytogenes by Polymerase Chain Reaction (PCR) in raw milk. We tested four different extraction protocols (generally identified: A, B, C, and D) for isolation of bacterial DNA directly from milk. In all of them was obtained identifying the product of 702 bp (base pairs) corresponding to the listeriolysin gene from L. monocytogenes . The protocol B containing proteinase K and phenol buffered, was chosen for the extraction of DNA from milk samples from eight dairy farms within the RS. The subsequent PCR amplification with DNA obtained by the protocol B allowed the identification of L. monocytogenes from 10 3 CFU/mL. None of the samples was positive for the producer L. monocytogenes by PCR or by conventional microbiological analysis. With this study it is concluded that the tested protocols, the protocol B was more effective for the detection of L. monocytogenes by PCR. Moreover, for the samples of the producers, the result PCR technique was obtained in a shorter time than conventional analysis of L. monocytogenes , which may allow earlier treatment of infected animals and thus avoid losses to the producer.