A Proteomic Investigation to Discover Candidate Proteins Involved in Novel Mechanisms of 5-Fluorouracil Resistance in Colorectal Cancer.

One of the main obstacles to therapeutic success in colorectal cancer (CRC) is the development of acquired resistance to treatment with drugs such as 5-fluorouracil (5-FU). Whilst some resistance mechanisms are well known, it is clear from the stasis in therapy success rate that much is still unknown. Here, a proteomics approach is taken towards identification of candidate proteins using 5-FU-resistant sublines of human CRC cell lines generated in house. Using a multiplexed stable isotope labelling with amino acids in cell culture (SILAC) strategy, 5-FU-resistant and equivalently passaged sensitive cell lines were compared to parent cell lines by growing in Heavy medium with 2D liquid chromatography and Orbitrap Fusion™ Tribrid™ Mass Spectrometry analysis. Among 3003 commonly quantified proteins, six (CD44, APP, NAGLU, CORO7, AGR2, PLSCR1) were found up-regulated, and six (VPS45, RBMS2, RIOK1, RAP1GDS1, POLR3D, CD55) down-regulated. A total of 11 of the 12 proteins have a known association with drug resistance mechanisms or role in CRC oncogenesis. Validation through immunodetection techniques confirmed high expression of CD44 and CD63, two known drug resistance mediators with elevated proteomics expression results. The information revealed by the sensitivity of this method warrants it as an important tool for elaborating the complexity of acquired drug resistance in CRC.

An insight into the commercial piglet's microbial gut colonization: from birth towards weaning.

BACKGROUND: The establishment of the gut microbiota can be influenced by several perinatal factors, including, most importantly, the maternal microbiota. Moreover, early-life environmental variation affects gut microbial colonization and the intestinal health of offspring throughout life. The present study aimed to explore the development of piglet gut microbiota from birth to weaning in the commercial practice and also to assess how different farm environments could condition this process. Although it is possible to find in the literature other studies with similar objectives this work probably represents one of the few studies that make a systematic evaluation of such differential factors under a real scenario. To achieve this objective, we performed two trials. In a first Trial, we selected 2 farms in which we performed an intensive sampling (5 samples /animal) to characterize the gut colonization pattern during the first days of life and to identify the time window with the greatest impact. Both farms differed in their health status and the use of antimicrobials in the piglets. In a second Trial, we selected 4 additional farms with variable rearing conditions and a distinctive use of antimicrobials in the sows with a simplified sampling pattern (2 samples/animal). Faecal samples were obtained with swabs and DNA was extracted by using the PSP® Spin Stool DNA Kit and sequencing of the 16S rRNA gene (V3-V4 region) performed by Illumina MiSeq Platform. RESULTS: The present study contributes to a better understanding of microbiome development during the transition from birth to weaning in commercial conditions. Alpha diversity was strongly affected by age, with an increased richness of species through time. Beta diversity decreased after weaning, suggesting a convergent evolvement among individuals. We pinpointed the early intestinal colonizers belonging to Bacteroides, Escherichia-Shigella, Clostridium sensu stricto 1, and Fusobacterium genera. During lactation(d7-d21 of life), the higher relative abundances of Bacteroides and Lactobacillus genera were correlated with a milk-oriented microbiome. As the piglets aged and after weaning (d36 of life), increasing abundances of genera such as Prevotella, Butyricimonas, Christensenellaceae R-7 group, Dorea, Phascolarctobacterium, Rikenellaceae RC9 gut group, Subdoligranulum, and Ruminococcaceae UCG-002 were observed. These changes indicate the adaptation of the piglets to a cereal-based diet rich in oligosaccharides and starch. Our results also show that the farm can have a significant impact in such a process, evidencing the influence of different environments and rearing systems on the gut microbiota development of the young piglet. Differences between farms were more noticeable after weaning than during lactation with changes in alpha and beta biodiversity and specific taxa. The analysis of such differences suggests that piglets receiving intramuscular amoxicillin (days 2-5 of life) and being offered an acidifying rehydrating solution (Alpha farm in Trial 1) have a greater alpha diversity and more abundant Lactobacillus population. Moreover, the only farm that did not offer any rehydrating solution (Foxtrot farm in Trial 2) showed a lower alpha diversity (day 2 of life) and increased abundance of Enterobacteriaceae (both at 2 and 21 days). The use of in-feed antibiotics in the sows was also associated with structural changes in the piglets' gut ecosystem although without changes in richness or diversity. Significant shifts could be registered in different microbial groups, particularly lower abundances of Fusobacterium in those piglets from medicated sows. CONCLUSIONS: In conclusion, during the first weeks of life, the pig microbiota showed a relevant succession of microbial groups towards a more homogeneous and stable ecosystem better adapted to the solid dry feed. In this relevant early-age process, the rearing conditions, the farm environment, and particularly the antimicrobial use in piglets and mothers determine changes that could have a relevant impact on gut microbiota maturation. More research is needed to elucidate the relative impact of these farm-induced early life-long changes in the growing pig.

Persistent sciatic artery aneurysm.

A persistent sciatic artery (PSA) is an exceptionally rare embryologic vascular anomaly with a reported incidence of 0.01-0.05% based on angiography. Most PSAs do not require treatment and 50% of affected individuals are asymptomatic. However, all PSA-related aneurysms should be treated because they involve a high risk of complications.We report the case of 53-year-old man with a 7-cm aneurysm arising from a left dominant PSA together with a hypoplastic left femoral artery, who presented with acute left limb ischemia. The patient had realized the presence of a pulsating mass in his left buttock 12 months before the ischemic event. He was treated initially with below-knee popliteal embolectomy and exclusion of the aneurysm with 2 overlapping, self-expanding, 10×50-mm stent grafts. On diagnosis, PSA aneurysms require neither potentially harmful ligation nor a technically challenging open procedure. Endovascular aneurysm exclusion using an antegrade or a retrograde approach is safe and efficient; however, long-term follow-up is required to establish the efficacy of this endovascular procedure.

Expressão das proteínas p53, p16 e ki67 no adenocarcinoma da cabeça do pâncreas e sua relação com a sobrevida e diferenciação celular / Expression of p53, p16 and Ki67 proteins in ductal adenocarcinoma of the pancreatic head and their relation with survival and cell differentiation

Objective: To determine the expression of p53, p16 and Ki-67 and its relevance in survival and cell differentiation. Methods: Fifteen duodenopancreatectomized patients were included. Immunohistochemical expression of p53, p16 and Ki-67 was determined in paraffin embedded tumor blocks. The relation of these expressions with different variables was studied. Results: Ninetythree per cent of tumors showed expression of p53 and p16. Ki- 67 was expressed in 86.66% of tumors (labeling index plus or minus LI 11.91 ± 9.47). The presence of combined alterations was not related to significant differences in tumor type, stage or survival; similar results were obtained analyzing isolated expressions. When groups of p16 and Ki-67 expressions where created, the median survival was not significant. However, there was a slightly better survival in patientswith focal expression of p16 (median survival 20.75 versus 14.34), when compared to patients with diffuse expression. Conclusion: The overexpression of p53, p16 and Ki-67 was not related to survival or tumor grade, when comparing isolated or combined expressions.

Objetivo: Determinar a expressão de p53, p16 e Ki-67 e sua relevância na sobrevida e diferenciação celular. Métodos: Foram incluídos 15 pacientes submetidos a duodenopancreatectomia. A expressão imunohistoquímica de p53, p16 e Ki-67 foi determinada em blocos tumorais embebidos em parafina. Foi estudada a relação dessas expressões com as variáveis. Resultados: Noventa e três por cento dos tumores apresentaram expressão de p53 e p16. Ki-67 estava expresso em 86,66% dos tumores (índice proliferativo mais ou menos IP 11,91 ± 9,47). A presença de alterações combinadas não estava relacionada a diferenças significativas no tipo tumoral, no estágio ou na sobrevida; resultados semelhantes foram obtidos com a análise de expressões isoladas. Quando foram criados os grupos de expressões de p16 e Ki-67, a sobrevida mediana não era significativa. Entretanto, havia uma sobrevida discretamente melhor nos pacientes com expressão focal do p16 (sobrevida mediana 20,75 versus 14,34) em comparação com pacientes com expressão difusa. Conclusão: A superexpressão das proteínas p53, p16 e Ki-67 não estava relacionada à sobrevida ou ao grau tumoral quando se compararam as expressões isoladas ou combinadas.

Expression of p53, p16 and Ki67 proteins in ductal adenocarcinoma of the pancreatic head and their relation with survival and cell differentiation.

OBJECTIVE: To determine the expression of p53, p16 and Ki-67 and its relevance in survival and cell differentiation. METHODS: Fifteen duodenopancreatectomized patients were included. Immunohistochemical expression of p53, p16 and Ki-67 was determined in paraffin embedded tumor blocks. The relation of these expressions with different variables was studied. RESULTS: Ninety-three per cent of tumors showed expression of p53 and p16. Ki-67 was expressed in 86.66% of tumors (labeling index - LI 11.91 ± 9.47). The presence of combined alterations was not related to significant differences in tumor type, stage or survival; similar results were obtained analyzing isolated expressions. When groups of p16 and Ki-67 expressions where created, the median survival was not significant. However, there was a slightly better survival in patients with focal expression of p16 (median survival 20.75 versus 14.34), when compared to patients with diffuse expression. CONCLUSION: The overexpression of p53, p16 and Ki-67 was not related to survival or tumor grade, when comparing isolated or combined expressions.

Selective approach for venous drainage in right iliac vein and cava vein for combined pancreas-kidney transplantation.

In this paper, the authors evaluate if the use of a venous drainage system in the cava vein (instead of the external iliac vein) presents differences in pancreatic transplantation. Between December 2000 and 2004, 105 pancreas-kidney transplants were performed. Patients in group A (n=49) underwent complete liberation of the right iliac vein for venous drainage. In group B (n=56), the venous drainage system was placed in the cava vein or in the confluence. Analyzed clinical parameters included: insulin replacement, vascular thrombosis in the graft, intraabdominal collections, graft loss, reoperation, and deaths. When compared to the external iliac vein, venous drainage to the cava vein did not result in significant differences. Venous drainage to the cava vein is a valuable alternative when the right iliac fossa has been previously approached. It is a practical, rapid procedure and it is not necessary to expose the internal iliac vein.

Dieulafoy lesion: endoscopic and surgical management.

Dieulafoy lesion is characterized by exteriorization of a large pulsatile arterial vessel through a minimal mucosal tear surrounded by normal mucosa, causing massive and recurrent upper digestive bleeding in previously healthy patients. More frequently presented than diagnosed, with the increase of its knowledge among endoscopists, a large number of cases are expected in the literature. Data from patients with upper gastrointestinal bleeding submitted to endoscopy at the Federal University of São Paulo, Gastrointestinal Endoscopy Unit from 1991 through 2002 were reviewed for Dieulafoy lesion. We found 15 patients with typical Dieulafoy gastric lesion. Their ages ranged from 18 to 78 years (mean age 49.9); 5 patients were female and 10 were male. Bleeding presented as hematemesis and melena in 7 cases (46.6%), hematemesis alone in 4 cases (26.6%), and melena alone in the other 4 cases (26.6%). Initial hemostatic approaches employed were: alcoholization (2 cases), epinephrine associated with alcohol injection (5 cases), sclerosis in 7 cases and surgery in 1 case. Dieulafoy lesion is a distinct nosologic entity that must be suspected in patients with massive digestive bleeding. Endoscopy became the procedure of choice for diagnosis and treatment of this disease.

Numerical study of the spectral 3-D green's function singularities for piezoelectric SAW components.

This article deals with the numerical study of the singularities appearing in the spectral 3-D Green's function associated with the piezoelectric surface acoustic wave components (so-called SAW components). These electrical units are currently used today in several devices produced by the telecommunications industry (radio, TV, radar, and digital telecommunication systems). The need to improve their performance has motivated engineers and researchers to use mathematical modeling intensively, in particular the integral equations technique here used, which requires the computing of the associated Green's function and the study of its properties.