954 resultados para Gastric-mucosal Barrier
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Apoptosis has an essential function in maintaining the integrity of the gastrointestinal mucosa. Its deregulation is associated with the occurrence of lesions such as in atrophic gastritis, peptic ulcers, intestinal metaplasia, and stomach tumorigenesis. Thus, the aim of the present study was to investigate the frequency of apoptotic cells (apoptotic index, AI) by using two different immunohistochemical techniques, TUNEL and anti-activated caspase-3 antibody (CPP32), in gastric dyspepsia [chronic gastritis (CG, N = 34), chronic atrophic gastritis (CAG, N = 11), gastric ulcer (GU, N = 17), and intestinal metaplasia (IM, N = 15)], normal gastric mucosae (NM, N = 8), and gastric adenocarcinoma (GC, N = 12). The relationship was investigated between the AI and Helicobacter pylori infection, diagnosed by PCR, overexpression of p53 protein determined by immunohistochemistry, and aneuploidy by fluorescence in situ hybridization, as performed by our laboratory in previous studies. No significant differences were observed in AI between the different groups, whether by the TUNEL technique (F = 1.60; P = 0.1670) or by CPP32 antibody (F = 1.70; P = 0.1420). Nonetheless, CAG and CG groups had AI statistically higher than those of normal mucosae. These two groups (CAG and CG) also showed a higher frequency of apoptosis-positive cases (TUNEL+ or CPP32+). Generally, there was no correlation between the AI detected by the TUNEL and CPP32 techniques in the groups studied, except in the GC group (r = 0.70). Moreover, there was no significant association between apoptosis and H. pylori infection, overexpression of p53 protein and aneuploidy, but the H. pylori-positive cases only of GU (P = 0.0233) and IM (P = 0.0253) groups displayed a statistically higher AI compared to H. pylori-negative NM, when the CPP32 antibody technique was used. Thus, CG and CAG have increased apoptosis, which may occur independent of an association with H. pylori infection, aneuploidy and overexpression of p53 protein. ©FUNPEC-RP.
A novel biomagnetic instrumentation with four magnetoresistive sensors to evaluate gastric motility.
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A novel instrumentation using anisotropic magnetoresistive (AMR) sensors associated with magnetic coils excitation was developed to evaluate gastrointestinal tract motility parameters. The susceptometer has four sensors that were used to measure the gastric activity contractions (GAC) in anaesthetized dogs, its performance was evaluated by manometry with good results.
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Twenty-two 14C datings were performed at the central sector of the Paraná coast to define Holocene regressive barrier evolution. The barrier Pleistocene substratum was ascribed an age between 40 400 and 30 000 yr BP, but it can also represent the penultimate sea level highstand during marine isotope stage 5e. The Holocene barrier samples provided ages between 8542-8279 and 2987-2751 cal yr BP, and showed at least six age inversions that were related to age differences between in situ or low-distance transported shells or trunk fragments, and high-distance transported vegetal debris, wood fragments and organic matter samples. The regressive Holocene barrier age was 4402-4135 cal yr BP near the base, and 2987-2751 cal yr BP near the top. Most of the vegetal remains were transported by ebb tidal currents from the estuaries to the inner shelf below wave base level during the mid-Holocene highstand; they were transported onshore by storm waves and littoral currents during the sea level lowering after the sea level maximum, and were deposited mainly as middle shoreface swaley cross-stratification facies. © 2008.
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the aim of this study was to validate the Alternate Current Biosusceptometry (ACB) for monitoring gastric contractions in rats. In vitro data were obtained to establish the relationship between ACB and the strain-gauge (SG) signal amplitude. In vivo experiments were performed on rats with magnetic markers and SGs previously implanted under the gastric serosa. The effects of the prandial state in gastric motility profiles were obtained. The correlation between in vitro signal amplitudes was strong (R = 0.989). The temporal cross-correlation between the ACB and SG signal amplitude was higher in the postprandial than in the fasting state. Irregular signal profiles, low contraction amplitudes, and smaller signal-to-noise ratios explained the poor correlation for fasting-state recordings. The contraction frequencies using ACB were 0.068 ± 0.007 Hz (postprandial) and 0.058 ± 0.007 Hz (fasting) and those using SG were 0.066 ± 0.006 Hz (postprandial) and 0.059 ± 0.008 Hz (fasting) (P < 0.003). When a magnetic tracer was ingested, there was a strong correlation and a small phasedifference between techniques. We conclude that ACB provides an accurate and sensitive technique for studies of GI motility in the rat. © 2010 IEEE.
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Alchornea triplinervia (Spreng.) Muell. Arg (Euphorbiaceae) is a medicinal plant commonly used by people living in the Cerrado region of Brazil to treat gastrointestinal ulcers. We previously described the gastroprotective action of methanolic extract (ME) of Alchornea triplinervia and the ethyl acetate fraction (EAF) in increasing of prostaglandin E 2 (PGE 2) gastric levels in the mucosa. In this work we evaluated the effect of EAF in promoting the healing process in rats with acetic acid-induced gastric ulcers. In addition, toxicity was investigated during treatment with EAF. After 14 days of treatment with EAF, the potent stimulator of gastric cell proliferation contributed to the acceleration of gastric ulcer healing. Upon immunohistochemical analysis, we observed a pronounced expression of COX-2, mainly in the submucosal layer. The 14-day EAF treatment also significantly increased the number of neutrophils in the gastric mucosa regeneration area. The EAF induced angiogenesis on gastric mucosa, observed as an increase of the number of blood vessels supplying the stomach in rats treated with EAF. Oral administration for 14 days of the ethyl acetate fraction from Alchornea triplinervia accelerated the healing of gastric ulcers in rats by promoting epithelial cell proliferation, increasing the number of neutrophils and stimulation of mucus production. This fraction, which contained mainly phenolic compounds, contributed to gastric mucosa healing. © 2011 by the authors; licensee MDPI, Basel, Switzerland.
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In this work, air dielectric barrier discharge (DBD) operating at the line frequency (60 Hz) or at frequency of 17 kHz was used to improve the wetting properties of polypropylene (PP). The changes in the surface hydrophilicity were investigated by contact angle measurements. The plasma-induced chemical modifications of PP surface were studied by X-ray photoelectron spectroscopy (XPS) and Fourier-transformed infrared spectroscopy (FTIR). The polymer surface morphology and roughness before and after the DBD treatment were analyzed by atomic force microscopy (AFM). To compare the plasma treatment effect at different frequencies the variation of the contact angle is presented as a function of the deposited energy density. The results show that both DBD treatments leaded to formation of water-soluble low molecular weight oxidized material (LMWOM), which agglomerated into small mounts on the surface producing a complex globular structure. However, the 60 Hz DBD process produced higher amount of LMWOM on the PP surface comparing to the 17 kHz plasma treatment with the same energy dose. The hydrophilic LMWOM is weakly bounded to the surface and can be easily removed by polar solvents. After washing the DBD-treated samples in de-ionized water their surface roughness and oxygen content were reduced and the PP partially recovered its original wetting characteristics. This suggested that oxidation also occurred at deeper and more permanent levels of the PP samples. Comparing both DBD processes the 17 kHz treatment was found to be more efficient in introducing oxygen moieties on the surface and also in improving the PP wetting properties. © 2012 Elsevier B.V. All rights reserved.
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The main objective of this article is to discuss the Brazilian environmental legislation and policies towards the development of navigation and port management. The research illustrated some difficulties faced by the country and make suggestions to overcome it. The construction of the environmental legal framework began in the early 1960s and resulted in a very complex system, as a consequence of policies adopted by the country. Nowadays Brazilian environmental policies are developed in democratic and participative way, although with elevated degree of bureaucracy and lack of integration among the several governmental agencies, which makes the approval of environmental certifications demand several years for new port projects or improvements, which delays the economic development of the country. Efforts have been made to simplify the licensing process. As result of this research two flowchart for environmental licenses of ports installation are shown: The first shows the process until 2009 and the second shows the process nowadays. This become an important issue due the fact that inland navigation is one of the less pollutant modes of transportation, and although, the process of environmental certification was simplified, if compare with 2009, it is still complex and time-consuming, delaying the development of the infrastructure. © 2012 Elsevier Ltd.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Gastric cancer is a leading cause of cancer-related mortality, and the presence of lymph node metastasis an important prognostic factor. Downregulation of RKIP has been associated with tumor progression and metastasis in several types of neoplasms, being currently categorized as a metastasis suppressor gene. Our aim was to determine the expression levels of RKIP in gastric tissues and to evaluate its impact in the clinical outcome of gastric carcinoma patients. RKIP expression levels were studied by immunohistochemistry in a series of gastric tissues. Overall, we analysed 222 non-neoplastic gastric tissues, 152 primary tumors and 42 lymph node metastasis samples. We observed that RKIP was highly expressed in ∼83% of non-neoplastic tissues (including normal tissue and metaplasia), was lost in ∼56% of primary tumors and in ∼90% of lymph node metastasis samples. Loss of RKIP expression was significantly associated with several markers of poor clinical outcome, including the presence of lymph node metastasis. Furthermore, the absence of RKIP protein constitutes an independent prognostic marker for these patients. In conclusion, RKIP expression is significantly lost during gastric carcinoma progression being almost absent in lymph node metastasis samples. Of note, we showed that the absence of RKIP expression is associated with poor outcome features of gastric cancer patients, this being also an independent prognostic marker.
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Objective. The anti-inflammatory proteins annexin-A1 and galectin-1 have been associated with tumor progression. This scenario prompted us to investigate the relationship between the gene and protein expression of annexin-A1 (ANXA1/AnxA1) and galectin-1 (LGALS1/Gal-1) in an inflammatory gastric lesion as chronic gastritis (CG) and gastric adenocarcinoma (GA) and its association with H. pylori infection. Methods. We analyzed 40 samples of CG, 20 of GA, and 10 of normal mucosa (C) by the quantitative real-time PCR (qPCR) technique and the immunohistochemistry assay. Results. High ANXA1 mRNA expression levels were observed in 90% (36/40) of CG cases (mean relative quantification RQ = 4.26 ± 2.03) and in 80% (16/20) of GA cases (mean RQ = 4.38 ± 4.77). However, LGALS1 mRNA levels were high (mean RQ = 2.44 ± 3.26) in 60% (12/20) of the GA cases, while low expression was found in CG (mean RQ = 0.43 ± 3.13; P < 0.01). Normal mucosa showed modest immunoreactivity in stroma but not in epithelium, while stroma and epithelium displayed an intense immunostaining in CG and GA for both proteins. Conclusion. These results have provided evidence that galectin-1 and mainly annexin-A1 are overexpressed in both gastritis and gastric cancer, suggesting a strong association of these proteins with chronic gastric inflammation and carcinogenesis. © 2013 Yvana Cristina Jorge et al.
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Background: Chronic inflammation and gastric carcinogenesis show a close association, so gene polymorphisms that modify the intensity of the inflammatory response may contribute to variations in gastric cancer risk. Aims: The purpose of this study was to investigate the combined effect of the pro- and anti-inflammatory cytokines and toll-like receptors polymorphisms on the chronic gastritis and gastric cancer risk in a Brazilian population sample. Methods: We evaluated 669 DNA samples (200 of gastric cancer [GC], 229 of chronic gastritis [CG], and 240 of healthy individuals [C]). Ten polymorphisms were genotyped: IL-1RN and TLR2 -196 to -174 del using the allele-specific PCR method and TNF-A (rs1800629; rs1799724), TNF-B (rs909253), IL-8 (rs4073; rs2227532), IL-10 (rs1800872) and TLR4 (rs4986790; rs4986791) using PCR-RFLP. Results: Polymorphisms TNF-A-308G/A, IL-8-251A/T, TNF-B + 252A/G and TLR4 + 1196C/T were not associated with risk of any gastric lesion. However, an association with increased risk for GC was observed for polymorphisms IL-1RNL/2 (p < 0.001), TNF-A-857C/T (p = 0.022), IL-8-845T/C (p < 0.001), IL-10-592C/A (p < 0.001), TLR2ins/del (p < 0.001), and TLR4 + 896A/G (p = 0.033). In CG, an association was observed only with polymorphisms IL-1RNL/2 and IL-10-592A/C (p < 0.001 for both). A combined analysis of these six polymorphisms associated with GC revealed a profile with two to four combined genotypes which confer a higher risk of gastric carcinogenesis, with an OR increased 2.95-fold to 50.4-fold, highlighting the combinations IL-1RN2/TNF-A-857T/IL-8-845C, IL-1RN2/IL-8-845C/TLR2del, IL-1RN2/IL-10-592A/TLR4 + 896G, IL-10-592A/TLR2del/ TLR4 + 896G, and IL-1RN2/TNFA-857T/IL8-845C/TLR2del. Conclusions: Our findings evidenced that the combined effect of polymorphisms in genes involved in the inflammatory process may potentiate the risk of gastric cancer, thus emphasizing the importance of evaluating multiple polymorphisms together. © 2012 Springer Science+Business Media New York.
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AIM: To study the association between atrophic gastritis (AG) and esophageal squamous cell carcinoma (ESCC) in a Latin-America population. METHODS: A case-control study was performed at two reference Brazilian hospitals including patients diagnosed with advanced ESCC and dyspeptic patients who had been subjected to upper gastrointestinal endoscopy, with biopsies of the gastric antrum and body. All cases with ESCC were reviewed by a single pathologist, who applied standard criteria for the diagnosis of mucosal atrophy, intestinal metaplasia, and dysplasia, all classified as AG. The data on the patients' age, sex, smoking status, and alcohol consumption were collected from clinical records, and any missing information was completed by telephone interview. The association between AG and ESCC was assessed by means of univariate and multiple conditional logistic regressions. RESULTS: Most patients were male, and the median age was 59 years (range: 37-79 years) in both the ESCC and control groups. Univariate analysis showed that an intake of ethanol greater than 32 g/d was an independent risk factor that increased the odds of ESCC 7.57 times (P = 0.014); upon multiple analysis, alcohol intake of ethanol greater than 32 g/d exhibited a risk of 4.54 (P = 0.081), as adjusted for AG and smoking. Smoking was shown to be an independent risk factor that increased the odds of ESCC 14.55 times (P = 0.011) for individuals who smoked 0 to 51 packs/year and 21.40 times (P = 0.006) for those who smoked more than 51 packs/year. Upon multiple analyses, those who smoked up to 51 packs/year exhibited a risk of 7.85 (P = 0.058), and those who smoked more than 51 packs/year had a risk 11.57 times higher (P = 0.04), as adjusted for AG and alcohol consumption. AG proved to be a risk factor that increased the odds of ESCC 5.33 times (95%CI: 1.55-18.30, P = 0.008) according to the results of univariate conditional logistic regression. CONCLUSION: There was an association by univariate conditional logistic regression between AG and ECSS in this sample of Latin-American population. © 2013 Baishideng.
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Background: Sex steroid exposure during early human development may influence disease susceptibility. Digit ratio (2D:4D) is a putative marker for prenatal hormone exposure and sensitivity, as well as the action of genes closely related to carcinogenesis. Digit ratio could act as a possible marker for cancer predisposition. Aims: The aim of this study is to investigate the possible correlations between right hand, left hand and right minus left (R. - L) 2D:4D and gastric cancer (GCA) in men and women and assess the correlations with tumor staging and histological diagnosis. Methods: Digital images of the right and left hand palms of patients diagnosed with GCA (n = 57, 42 males, 15 females) and age and sex-matched controls (n = 59, 41 males, 18 females) were obtained. Means for 2D:4D were compared. Data were analyzed by repeated-measures one-way ANOVA and Student's t-test for finger measurements and group comparisons and Pearson's and Spearman's tests for correlations with tumor staging (α = 0.05). Results: GCA group presented significantly higher left 2D:4D, but significantly lower R. - L in comparison to healthy controls, particularly so for males. Digit ratio did not correlate to clinical staging or TNM staging. However, low R. - L was significantly related to adenocarcinomas. Conclusions: Early developmental conditions, including prenatal testosterone seem to play a role on the malignant transformation of gastric lesions. The 2D:4D pattern found for gastric cancer parallels that earlier described for breast cancer. The findings suggest that 2D:4D could add to the list of etiological factors and be a putative marker for the screening of patients' susceptibility to develop gastric cancer. © 2012 Elsevier Ltd.