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Ana Filipa

Both Helicobacter pylori genotype and host genetic polymorphisms play a role in determining the clinical consequences of H. pylori infection. We investigated whether there are any combinations of bacterial and host genotypes that are... more
Both Helicobacter pylori genotype and host genetic polymorphisms play a role in determining the clinical consequences of H. pylori infection. We investigated whether there are any combinations of bacterial and host genotypes that are particularly associated with the occurrence of gastric carcinoma. Genotypic variations in virulence-associated genes of H. pylori vacA (s and m regions) and cagA were determined in 221 subjects with chronic gastritis and 222 patients with gastric carcinoma by polymerase chain reaction (PCR)-line probe assay. Polymorphisms in the human interleukin 1 beta (IL-1B) gene (IL-1B-511*C or IL-1B-511*T) and in the IL-1 receptor antagonist gene (IL-1RN intron 2 variable number of tandem repeats) were evaluated by PCR and single-strand conformation polymorphism analysis. All statistical tests were two-sided. Infection with vacAs1-, vacAm1-, and cagA-positive strains of H. pylori was associated with an increased risk for gastric carcinoma, with odds ratios (ORs) of 17 (95% confidence interval [CI] = 7.8 to 38), 6.7 (95% CI = 3.6 to 12), and 15 (95% CI = 7.4 to 29), respectively. IL-1B-511*T carriers (IL-1B-511*T/*T or IL-1B-511*T/*C) homozygous for the short allele of IL-1RN (IL-1RN*2/*2) had an increased gastric carcinoma risk (OR = 3.3, 95% CI = 1.3 to 8.2). For each combination of bacterial/host genotype, the odds of having gastric carcinoma were greatest in those with both bacterial and host high-risk genotypes: vacAs1/IL-1B-511*T carrier (OR = 87, 95% CI = 11 to 679), vacAm1/IL-1B-511*T carrier (OR = 7.4, 95% CI = 3.2 to 17), cagA-positive/IL-1B-511*T carrier (OR = 25, 95% CI = 8.2 to 77), vacAs1/IL-1RN*2/*2 (OR = 32, 95% CI = 7.8 to 134), vacAm1/IL-1RN*2/*2 (OR = 8.8, 95% CI = 2.2 to 35), and cagA-positive/IL-1RN*2/*2 (OR = 23, 95% CI = 7.0 to 72). Combined bacterial/host genotyping may provide an important tool in defining disease risk and targeting H. pylori eradication to high-risk individuals.
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The standard (p∘=0.1MPa) molar energies of combustion, ΔcUm∘, for the crystalline 2-thiophenecarboxylic acid hydrazide and 2-furancarboxylic acid hydrazide were determined, at the temperature of 298.15K, by rotating bomb and static bomb... more
The standard (p∘=0.1MPa) molar energies of combustion, ΔcUm∘, for the crystalline 2-thiophenecarboxylic acid hydrazide and 2-furancarboxylic acid hydrazide were determined, at the temperature of 298.15K, by rotating bomb and static bomb combustion calorimetry, respectively. For these compounds, the standard molar enthalpies of sublimation, ΔcrgHm∘, at T = 298.15K, were derived by the Clausius–Clapeyron equation, from the temperature dependence of the
Background Surgery is the best treatment for primary GIST and may be curative, but resection extension/completeness impact on the prognosis remains controversial. The authors aim was to evaluate the clinicopathological (CP) parameters and... more
Background Surgery is the best treatment for primary GIST and may be curative, but resection extension/completeness impact on the prognosis remains controversial. The authors aim was to evaluate the clinicopathological (CP) parameters and surgical margins status influence on GIST patients’ outcome. Materials and methods The study evaluated 113 consecutive patients with sporadic GIST; the influence of CP parameters on recurrence-free survival (RFS) and disease-specific survival (DSS) was determined by univariate analysis (UA) and multivariate analysis (MA). Results Of 104 cases, macroscopically complete resection was achieved in 96: R0 surgical margin status in 78 and R1 in 18. Recurrence rates (12.5%) were significantly lower in R0 (9.0%) than in R1 (27.8%). Tumor >10 cm, mitotic count >5/50 high power field (HPF), and high-risk GIST predicted poor RFS and DSS (UA). Disease-specific survival was significantly shorter after macroscopic incomplete (R2) resection, for mixed cellular morphology, and in tumors with necrosis (UA). High-risk GIST (p = 0.016) and R2 resection (p = 0.013) predicted poor DSS of patients (MA). Conclusions High risk and positive macroscopic surgical margin status are parameters associated with poor disease-specific survival in GIST patients.
The Asian weatherloach, Misgurnus anguillicaudatus (Cobitidae), is a facultative air-breathing teleost fish that makes use of its hindgut or intestine as an accessory air-breathing organ (ABO). The hindgut is highly modified, being well... more
The Asian weatherloach, Misgurnus anguillicaudatus (Cobitidae), is a facultative air-breathing teleost fish that makes use of its hindgut or intestine as an accessory air-breathing organ (ABO). The hindgut is highly modified, being well vascularized with intraepithelial capillaries, which makes it well suited for gas exchange. However, the consequences for nutrient uptake, the traditional function of the intestine are unknown. The alimentary canal was examined histologically to assess differences between the fore-, mid- and hindgut regions that have been considered as the digestive, spiral and respiratory zones, respectively. In order to characterise the potential digestive (absorptive) function of the respiratory zone we used semi-quantitative polymerase chain reaction (PCR) to detect the presence of the intestinal Na(+):glucose cotransporter (SGLT1; SLC5A1) and H(+):peptide cotransporter (PEPT1a; SLC15A1) and partially sequenced the SGLT1 and PEPT1a cDNAs. These two transporters play important roles in the absorption of carbohydrate and di-/tripeptides, respectively, in the gut of fishes and other vertebrates and were therefore used as markers for potential nutrient uptake function. We also determined their tissue distributions through semi-quantitative RT-PCR. The effects of diet composition (high protein or high carbohydrate) or fasting on gene expression were also examined. SGLT1 expression was found in kidney, liver, heart, as well as in the three zones of the gut except the most distal part of the hindgut. PEPT1a mRNA was found in heart, brain, liver, and fore- and midgut, but absent in the hindgut. Our results clearly show high expression of SGLT1 (both mRNA and protein by immunolocalization) and PEPT1a (mRNA) in the foregut and midgut correlated with the digestive region of the gut. Modulatory effects of diet on the gene expression for both SGLT1 and PEPT1a were not observed. The presence of SGLT1 transcripts in the respiratory zone of the intestine suggests an overlap in function. However, in the case of PEPT1a, the distal limit was the midgut. Thus, despite its highly modified structure, the hindgut of the loach retains some potential nutrient uptake function.
Petrological, geochemical, and Nd isotopic analyses have been carried out on rock samples from the Rainbow vent field to assess the evolution of the hydrothermal system. The Rainbow vent field is an ultramafic-hosted hydrothermal system... more
Petrological, geochemical, and Nd isotopic analyses have been carried out on rock samples from the Rainbow vent field to assess the evolution of the hydrothermal system. The Rainbow vent field is an ultramafic-hosted hydrothermal system located on the Mid-Atlantic Ridge characterized by vigorous high-temperature venting (∼365°C) and unique chemical composition of fluids: high chlorinity, low pH and very high Fe, and rare earth element (REE) contents (Douville et al., Chemical Geology 184:37–48, 2002). Serpentinization has occurred under a low-temperature (143Nd/144Nd isotope ratios. Vent fluid chemistry data are indicative of acidic, reducing, and high temperature conditions at the subseafloor reaction zone where fluids undergo phase separation most likely under subcritical conditions (boiling). An explanation for the high chlorinity is not straightforward unless mixing with high salinity brine or direct contribution from a magmatic Cl-rich aqueous fluid is considered. This study adds new data, which, combined with the current knowledge of the Rainbow vent field, brings compelling evidence for the presence, at depth, of a magmatic body, most likely gabbroic, which provides heat and metals to the system. Co/Ni ratios proved to be good tools used to discriminate between rock units, degree of sulfide mineralization, and positioning within the hydrothermal system. Deeper units have Co/Ni 1.