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Abstract This study aimed to determine the antiulcerogenic and antioxidant activities of Psyllium (Plantago ovata Forssk) seed ethanolic extract in rats. We assessed the antioxidant potential using free radical scavenging on DPPH, -carotene bleaching activity, ferric reducing power, and hydroxyl radical scavenging activity. In the antiulcerogenic study, pre-treatment with Plantago ovata seeds ethanolic extract (POE) (400 mg/kg b.wt) significantly protected against ethanol-induced gastric ulcer in rats by decreasing the ulcer index value and preserving the integrity of the gastric mucosa. The oxidative stress status in the stomach tissues showed a significant increase in the antioxidant enzyme levels of superoxide dismutase, catalase, and glutathione peroxidase with a significant decrease in lipid peroxidation during pre-treatment with POE. In conclusion, the POE protects against gastric ulcer due to its antioxidant potential and presence of bioactive molecules.

Resumo O presente estudo teve como objetivo determinar as atividades antiulcerogênica e antioxidante das sementes de Psyllium (Plantago ovata Forssk) em ratos. O potencial antioxidante foi avaliado utilizando o método do sequestro do radical livre DPPH, autooxidação do -caroteno, poder redutor de ferro e atividade de sequestro do radical hidroxila. No estudo antiulcerogênico, o pré-tratamento com o extrato etanólico das sementes de Plantago ovata (POE) (400 mg/Kg b.wt) reduziu a úlcera gástrica induzida pelo etanol em ratos, diminuindo o valor do índice de úlcera e preservando a integridade da mucosa gástrica. O estudo do estresse oxidativo nos tecidos estomacais mostrou um aumento significativo dos níveis das enzimas antioxidantes superóxido dismutase, catalase e glutationa peroxidase, com uma diminuição significativa da peroxidação lipídica enquanto pré-tratamento com POE. Em conclusão, o POE protege contra úlcera gástrica devido aos seus potenciais antioxidantes e à presença de moléculas bioativas.

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This study aimed to determine the antiulcerogenic and antioxidant activities of Psyllium (Plantago ovata Forssk) seed ethanolic extract in rats. We assessed the antioxidant potential using free radical scavenging on DPPH, ß-carotene bleaching activity, ferric reducing power, and hydroxyl radical scavenging activity. In the antiulcerogenic study, pre-treatment with Plantago ovata seeds ethanolic extract (POE) (400 mg/kg b.wt) significantly protected against ethanol-induced gastric ulcer in rats by decreasing the ulcer index value and preserving the integrity of the gastric mucosa. The oxidative stress status in the stomach tissues showed a significant increase in the antioxidant enzyme levels of superoxide dismutase, catalase, and glutathione peroxidase with a significant decrease in lipid peroxidation during pre-treatment with POE. In conclusion, the POE protects against gastric ulcer due to its antioxidant potential and presence of bioactive molecules.

O presente estudo teve como objetivo determinar as atividades antiulcerogênica e antioxidante das sementes de Psyllium (Plantago ovata Forssk) em ratos. O potencial antioxidante foi avaliado utilizando o método do sequestro do radical livre DPPH, autooxidação do ß-caroteno, poder redutor de ferro e atividade de sequestro do radical hidroxila. No estudo antiulcerogênico, o pré-tratamento com o extrato etanólico das sementes de Plantago ovata (POE) (400 mg/Kg b.wt) reduziu a úlcera gástrica induzida pelo etanol em ratos, diminuindo o valor do índice de úlcera e preservando a integridade da mucosa gástrica. O estudo do estresse oxidativo nos tecidos estomacais mostrou um aumento significativo dos níveis das enzimas antioxidantes superóxido dismutase, catalase e glutationa peroxidase, com uma diminuição significativa da peroxidação lipídica enquanto pré-tratamento com POE. Em conclusão, o POE protege contra úlcera gástrica devido aos seus potenciais antioxidantes e à presença de moléculas bioativas.

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SUMMARY OBJECTIVE: Colonic diverticulosis might be caused by low-fiber dietary habits, gastrointestinal motility disorders, and colonic wall resistance changes, which might also affect the upper gastrointestinal system mucosa. Therefore, the present study aims to answer whether the gastric histopathological findings of the cases with diverge from those without. METHODS: This retrospective cross-sectional study included 184 cases who underwent both upper and lower gastrointestinal endoscopy procedures between January 2020 and December 2022. Notably, 84 cases were colonic diverticulosis, while the rest of the study group was control. Their demographic, laboratory, and histopathological findings were compared meticulously. RESULTS: The median ages for the colonic diverticulosis and control were 67.07±8.14 and 66.29±15.83 years, respectively, and no statistical difference concerning the age and gender distribution between them was recognized. The median levels of white blood cells, neutrophils, glucose, creatinine, and aspartate aminotransferase in colonic diverticulosis were significantly increased compared to control. As for pathological comparison, colonic diverticulosis had a higher prevalence of Helicobacter pylori (45.2 vs. 38%), while atrophy and intestinal metaplasia prevalence were nearly the same in the groups, without significance regarding Helicobacter pylori. CONCLUSION: Consequently, colonic diverticulosis should not be overlooked, particularly when the abovementioned laboratory parameters are augmented in a dyspeptic patient. A correlation might be raised between Helicobacter pylori and colonic diverticulosis. Eradication therapy might help attenuate the risk of colonic diverticulosis when Helicobacter pylori has emerged in a patient.

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SUMMARY: Mormodica balsamina is a valuable medicinal plant that is used to treat wounds and inflammation; its leaves are also used as an antibiotic and in the treatment of stomach pain. This study was conducted to determine the anti-ulcer activity of methanolic leaf extract of Mormodica balsamina on ethanol-induced ulcer in albino rats. A total of 32 rats were used for the study. Groups I and II served as the baseline and negative controls respectively, while groups III-VII served as the test groups. Group I was untreated, while group II received 1ml/kg body weight of the vehicle (2 % DMSO). Three test groups (III - V) received methanol extracts (75 mg, 150 mg, 300 mg/kg body weight respectively) while the other three test groups (VI - VIII) received aqueous extracts (75 mg, 150mg, 300 mg/kg body weight respectively) via oral gavage for seven days prior to ulcer induction. The rats were sacrificed, stomachs excised and ulcers scored. Histological sections were produced and examined. Findings revealed that M. balsamina extracts protected the rats' gastric epithelia from ethanol induced ulceration to varying degree with the high dose (150 and 300 mg/kg) of both extracts offering the best preservation (42 % and 50 % ulcer protective index respectively) when compared to untreated animals. Histological findings correlated with calculated ulcer indices, with treated animals having less severe gastric mucosal lesions. In conclusion, extracts of M. balsamina may possess reasonable antiulcer activities in rats against ethanol induced gastric ulcer.

Mormodica balsamina es una valiosa planta medicinal que se utiliza para tratar heridas e inflamaciones; sus hojas también se utilizan como antibiótico y en el tratamiento del dolor de estómago. Este estudio se realizó para determinar la actividad antiulcerosa del extracto metanólico de hojas de Mormodica balsamina sobre la úlcera inducida por etanol en ratas albinas. Se utilizaron un total de 32 ratas para el estudio. Los grupos I y II sirvieron como referencia y controles negativos respectivamente, mientras que los grupos III-VII sirvieron como grupos de prueba. El grupo I no se trató, mientras que el grupo II recibió 1 ml/kg de peso corporal del vehículo (2% de DMSO). Tres grupos de prueba (III - V) recibieron extractos de metanol (75 mg, 150 mg, 300 mg/ kg de peso corporal respectivamente) mientras que los otros tres grupos de prueba (VI - VIII) recibieron extractos acuosos (75 mg, 150 mg, 300 mg/kg de peso corporal respectivamente) por sonda oral durante siete días antes de la inducción de la úlcera. Se sacrificaron las ratas, se extirparon los estómagos y se puntuaron las úlceras. Se realizaron y examinaron secciones histológicas. Los resultados revelaron que los extractos de M. balsamina protegieron el epitelio gástrico de las ratas de la ulceración inducida por etanol en diversos grados, y la dosis alta (150 y 300 mg/kg) de ambos extractos ofreció la mejor conservación (42 % y 50 % de índice de protección contra úlceras, respectivamente) en comparación con los animales no tratados. Los hallazgos histológicos se correlacionaron con los índices de úlcera calculados, y los animales tratados tenían lesiones de la mucosa gástrica menos graves. En extractos de M. balsamina puede poseer actividades antiulcerosas razonables en ratas contra la úlcera gástrica inducida por etanol.

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Marginal zone lymphomas rank as the third most prevalent form of non-Hodgkin B-cell lymphoma, trailing behind diffuse large B-cell lymphoma and follicular lymphoma. Gastric mucosa-associated lymphoid tissue lymphoma (GML) is a low-grade B-cell neoplasia frequently correlated with Helicobacter pylori (H. pylori)-induced chronic gastritis. On the other hand, a specific subset of individuals diagnosed with GML does not exhibit H. pylori infection. In contrast to its H. pylori-positive counterpart, it was previously believed that H. pylori-negative GML was less likely to respond to antimicrobial therapy. Despite this, surprisingly, in-creasing evidence supports that a considerable proportion of patients with H. pylori-negative GML show complete histopathological remission after bacterial eradication therapy. Nonetheless, the precise mechanisms underlying this treatment responsiveness are not yet fully comprehended. In recent years, there has been growing interest in investigating the role of non-H. pylori gastric helicobacters (NHPHs) in the pathogenesis of H. pylori-negative GML. However, additional research is required to establish the causal relationship between NHPHs and GML. In this minireview, we examined the current understanding and proposed prospects on the involvement of NHPHs in H. pylori-negative GML, as well as their potential response to bacterial eradication therapy.

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BACKGROUND: Gastric mucosa-associated lymphoid tissue (MALT) lymphoma (GML) is usually a low-grade B-cell neoplasia strongly associated with Helicobacter pylori (H. pylori)-induced chronic gastritis. Clinical practice guidelines currently recommend H. pylori eradication as the preferred initial treatment for early-stage GML. To determine the practical effect of bacterial eradication as the sole initial therapy for early-stage GML, an updated analysis and review of available evidence is imperative. AIM: To perform a meta-analysis to assess the rate of complete remission (CR) of H. pylori-positive early-stage GML following bacterial eradication. METHODS: We performed independent, computer-assisted literature searches using the PubMed/MEDLINE, Embase, and Cochrane Central databases through September 2022. Prospective and retrospective observational studies evaluating the CR of early-stage GML following bacterial eradication in H. pylori-positive patients. The risk of bias was assessed using Joanna Briggs Institute (JBI) Critical Appraisal Tools. The pooled estimate of the complete histopathological remission rate and respective confidence intervals (95%CI) were calculated following the random-effects model. Heterogeneity and inconsistency were assessed using Cochran's Q test and I2 statistic, and heterogeneity was defined as P < 0.01 and I² > 50%, respectively. Subgroup and meta-regression analyses were conducted to explore potential sources of heterogeneity. RESULTS: The titles and abstracts of 1576 studies were screened; 96 articles were retrieved and selected for full-text reading. Finally, 61 studies were included in the proportional meta-analysis (P-MA). Forty-six were prospective and fifteen were retrospective uncontrolled, single-arm, observational studies. The overall risk of bias was low to moderate in all but a single report, with an average critical appraisal score across all studies of 79.02%. A total of 2936 H. pylori-positive early-stage GML patients, in whom H. pylori was successfully eradicated, were included in the analysis. The pooled CR of H. pylori-positive early-stage GML after bacterial eradication was 75.18% (95%CI: 70.45%-79.91%). P-MA indicated the substantial heterogeneity in CR reported across studies (I 2 = 92%; P < 0.01). Meta-regression analysis identified statistically significant effect modifiers, including the proportion of patients with t(11;18)(q21;q21)-positive GML and the risk of bias in each study. CONCLUSION: Comprehensive synthesis of available evidence suggests that H. pylori eradication is effective as the sole initial therapy for early-stage GML. Although the substantial heterogeneity observed across studies limits the interpretation of the pooled overall CR, the present study is a relevant to informing clinical practice.

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Siendo el cáncer gástrico la 3ª causa de muerte por cáncer en Chile, y existiendo estrategias de tamizaje consistentes en pesquisa de lesiones preneoplásicas de la mucosa gástrica, es relevante conocer los aspectos genéticos y moleculares que puedan ser aplicados, en la optimización de dichas estrategias a grupos de mayor riesgo. El objetivo de este manuscrito fue revisar la evidencia actual en los aspectos señalados, y de la inmunohistoquímica de 4 marcadores (p53, CDX2, MUC2 y S100A9) en la mucosa gástrica normal y en las lesiones preneoplásicas de la misma.

SUMMARY: Since gastric cancer is the 3rd leading cause of death from cancer in Chile, and there are screening strategies consisting of screening for preneoplastic lesions of the gastric mucosa, it is important to know certain genetic and molecular aspects that can be applied in optimizing these strategies for higher risk groups. The aim of this manuscript was to review the current evidence on the aforementioned aspects, and on the immunohistochemistry of 4 markers (p53, CDX2, MUC2 and S100A9) in normal gastric mucosa and in its preneoplastic lesions.

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Helicobacter pylori infection is widespread worldwide, with more than a half of the world population infected. H. pylori antibiotic-resistant strains and non-compliance to therapy are the major causes of H. pylori eradication failure. The search for new therapies based on plant extracts is a scientific interest field. The present study was conducted to evaluate the effect in vitro of extra virgin olive oil (EVOO), hydroxytyrosol (HT), and oleuropein (Olp) against two H. pylori strains and the effect in vivo of the oral administration of EVOO on the gastric mucosa of BALB/c mice infected with this microorganism. The broth microdilution method assayed the antibacterial in vitro activity of EVOO, HT, and Olp against H. pylori strains. For in vivo studies, male BALB/c mice were infected orally with an H. pylori suspension every 72 h. Four groups were used: (1) Control, (2) H. pylori-infected (HP), (3) EVOO, and (4) HP + EVOO. Mice were sacrificed at 7, 15, and 30 days. The stomachs were removed and observed under a microscope. Scoring of the degree of erosion was determined. Samples were processed by histological techniques for light microscopy. Macroscopic analysis showed that the presence of small erosions increased, both in number and size, in the infected group. Animals infected and treated with EVOO exhibited the presence of fewer erosions, which decreased in number as the treatment progressed. The mucosa of the control and EVOO groups showed normal histological characteristics at the three times studied. The mucosa of animals infected with H. pylori showed disruptions of the lining epithelium, damage to gastric glands, and vasodilation. The mucosa of animals infected with H. pylori and treated with EVOO showed morphological characteristics similar to those of normal and EVOO mucosa. For the first time, the current study showed the effect in vitro and in vivo of EVOO and combined administration of HT and Olp against H. pylori using an animal model. Future studies are needed to establish the mechanism of EVOO's action at the gastric mucosa level to propose this product as a natural antimicrobial agent for the treatment of gastric H. pylori infections.

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Helicobacter pylori es un microrganismo que se considera que afecta al 50% de la población. Se realizó un estudio con diseño no experimental, correlacional y transversal, con el objetivo de determinar la asociación de los resultados de pruebas diagnósticas de infección por H. pylori a través de biopsia obtenida por endoscopía superior y prueba de antígeno de la superficie en mues-tras de heces en 100 pacientes atendidos en el Servicio de Gastroenterología del Centro Clínico Quirúrgico Ambulatorio (Hospital del Día) Efrén Jurado López del Instituto Ecuatoriano de Seguridad Social (IESS), en la ciudad de Guayaquil, Ecuador, durante 2019. La media de la edad en la muestra de estudio fue 37,5 años, con un predominio del género femenino (78%). El 65% de las pruebas de antígeno para la detección de H. pylori en heces resultaron negativas. Los repor-tes de las pruebas de antígeno en heces e histopatología permitieron apreciar diferencias entre estos, pero con predominio de las coincidencias en los diagnósticos positivos. Existió una asocia-ción estadísticamente significativa entre las lesiones inflamatorias de la mucosa gástrica producto de la gastritis crónica atrófica y la infección por H. pylori. Los resultados de las dos pruebas diag-nósticas tuvieron una correlación lineal positiva y débil con significación estadística.

Helicobacter pylori is a microorganism that affects 50% of the population worldwide. A study with a non-experimental, correlational, and cross-sectional design was carried out in order to determine the association of the results of diagnostic tests for H. pylori infection through biopsy obtained by upper endoscopy and surface antigen test in samples of feces in 100 patients. These ones were treated at the Gastroenterology Service of the Ambulatory Surgical Clinic Center (Hospital del Día) Efrén Jurado López of the Ecuadorian Institute of Social Security (IESS), in the city of Guayaquil, Ecuador, during 2019. The mean age in the study sample was 37.5 years old, with a predominance of the female gender (78%). 65% of stool antigen tests for H. pyloriwere negative. The reports of the stool antigen test and histopathology allowed to appreciate differences between them, but with a predominance of the coincidences in the positive diagno-ses. There was a statistically significant association between the inflammatory lesions of the gastric mucosa because of chronic atrophic gastritis and the infection by H. pylori. The results of the two diagnostic tests had a positive and weak linear correlation with statistical significance

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ETHNOPHARMACOLOGICAL RELEVANCE: Leonurus sibiricus L. (Lamiaceae) is a medicinal plant known in Brazil as "rubim" or "erva de macaé". It is used for various purposes, including stomach disorders. AIM OF THE STUDY: To evaluate the effect of the ethanol extract of the aerial parts of L. sibiricus (EELs) in models of gastric damage in mice. MATERIAL AND METHODS: The effect of EELs (50, 100 and 300 mg/kg, p.o., 1 h before induction) was tested on acidified ethanol (ACEt)-induced gastric ulcers. Additionally, we tested the effect of EELs (by intraduodenal administration) in the pylorus ligation (PL) model. RESULTS: Pretreatment with EELs, at 300 mg/kg, but not 50 and 100 mg/kg, reduced the relative area of gastric ulcers induced by ACEt (p < 0.01) and lipoperoxidation (p < 0.001), and increased the sulfhydryl content (p < 0.01) in the stomach in comparison with the vehicle group. Pretreatment with N-ethylmaleimide (a blocker of non-protein sulfhydryl groups, 10 mg/kg, i.p.) or glibenclamide (a KATP channel blocker, 10 mg/kg, i.p.) inhibited the gastroprotective response caused by EELs (300 mg/kg; p < 0.001), but there were no alterations due to pretreatments with inhibitors of the synthesis of prostaglandins (indomethacin, 10 mg/kg), nitric oxide (L-NAME, 70 mg/kg) or hydrogen sulfide (DL-propargylglycine, 10 mg/kg). Treatment with EELs (300 mg/kg) reduced mucus production (p < 0.001) and the volume of gastric secretion (p < 0.001) after PL without affecting gastric acidity or pH. CONCLUSIONS: These results provide evidence that EELs exerts gastroprotective action in mice, with the participation of oxidative stress and mediation of NP-SH, KATP channels and mucus production.

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SUMMARY: The mucous substances of the stomach in mammals are important not only for the protection of the gastric epithelium from the acid environment and grinding actions, but it facilitates some other functions of the stomach such as antibacterial, antimetastatic, and immunological roles. The goal of the study is to highlight the distribution of mucin-secreting cells in the gastric mucosa in domestic rabbits, including the type of mucus synthesized. The gastric samples collected from ten individual rabbits were fixed in 10 % buffered formalin and underwent later standard paraffin tissue sample processing, which included dehydration, clarification, and embedding in paraffin. The tissue sections were eventually stained histochemically by PAS reaction and by Alcian blue method (pH 2.5) for neutral and acidic mucins detection, respectively. The quantification of mucins in the cytoplasm of mucus-secreting cells was performed by grading the gastric tissue samples from negative (-) to intensely positive (++). The mucus elaboration was observed in all the regions of the stomach (i.e., cardial, fundic, and pyloric regions), but only for the neutral mucin. The acidic mucin synthesis occurred only in the secretory units of the gastric glands from the cardial region in the stomach. Pyloric glands synthesized the largest amounts of neutral mucins, followed by moderate amounts elaborated by cardial glands, while the fundic region does not synthesize it at all. The description of new microscopic features of the stomach in rabbits is fundamental not only for comprehending species-related physiological features but gastric pathological processes.

RESUMEN: Las sustancias mucosas del estómago en los mamíferos son importantes no solo para la protección del epitelio gástrico del ambiente ácido y las acciones de trituración, sino que facilitan además otras funciones del estómago, como son las funciones antibacterianas, antimetastásicas e inmunológicas. El objetivo del estudio fue resaltar la distribución de las células secretoras de mucina en la mucosa gástrica de conejos domésticos, incluido el tipo de moco sintetizado. Las muestras gástricas recolectadas de diez conejos se fijaron en formalina tamponada al 10 % y se sometieron a un procesamiento que incluyó deshidratación, clarificación e inclusión en parafina. Las secciones de tejido finalmente se tiñeron histoquímicamente mediante la reacción de PAS y el método del azul de Alcian (pH 2,5) para la detección de mucinas neutras y ácidas, respectivamente. La cuantificación de mucinas en el citoplasma de las células secretoras de moco se realizó clasificando las muestras de tejido gástrico desde negativas (-) hasta intensamente positivas (++). La elaboración de moco se observó en todas las regiones del estómago (es decir, cardias, fúndica y pilórica), pero solo para la mucina neutra. La síntesis de mucina ácida ocurrió solo en las unidades secretoras de las glándulas gástricas de la región correspondiente al cardias del estómago. Las glándulas pilóricas sintetizaron la mayor cantidad de mucinas neutras, seguidas de cantidades moderadas elaboradas por las glándulas cardiales, mientras que la región fúndica no las sintetizó en abso- luto. La descripción de nuevas características microscópicas del estómago en conejos es fundamental no solo para comprender las características fisiológicas relacionadas con las especies sino también para entender los procesos patológicos gástricos.

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ABSTRACT Introduction The classification of intestinal metaplasia by histochemistry methods has been described as the most appropriate. However, current algorithms are not replicable in laboratories due to severe limitations. Objective To evaluate a new algorithm to differentiate histochemical types of intestinal metaplasia. Material and Method: Cross-sectional research in which 512 gastric biopsies with intestinal metaplasia (paraffin blocks) were evaluated by a new algorithm using two types of Alcian Blue dyes during February-March of 2020 in the pathological anatomy service of the Maria Auxiliadora Hospital, Lima, Peru. This evaluation consisted of two steps: visualization of acid mucins in the columnar cells of the gastric mucosa and calculation of the weighted Kappa statistic. Results Histochemical types of intestinal metaplasia showed as follows: Type I, 398 (77.7%); Type II, 81 (15.8%) and Type III, 33 (6.5%). The weighted Kappa statistic was 0.79 (p<0.001), rated as an important or good concordance. Conclusion This new algorithm demonstrated it was useful and capable of identifying and differentiating the histochemical types of intestinal metaplasia, in addition to having statistical reliability.

RESUMO Introdução A classificação da metaplasia intestinal por métodos histoquímicos tem sido descrita como a mais adequada. No entanto, os algoritmos atuais não são replicáveis?? em laboratórios devido a limitações severas. Objetivo Avaliar um novo algoritmo para diferenciar tipos histoquímicos de metaplasia intestinal. Material e Método: Pesquisa transversal em que 512 biópsias gástricas com metaplasia intestinal (blocos de parafina) foram avaliadas por um novo algoritmo usando dois tipos de corantes Alcian Blue durante fevereiro-março de 2020 no serviço de anatomia patológica do Hospital Maria Auxiliadora, Lima, Peru. Essa avaliação consistiu em duas etapas: visualização das mucinas ácidas nas células colunares da mucosa gástrica e cálculo da estatística Kappa ponderado. Resultados Os tipos histoquímicos de metaplasia intestinal mostraram-se a seguir: Tipo I, 398 (77,7%); Tipo II, 81 (15,8%) e Tipo III, 33 (6,5%). A estatística Kappa ponderado foi de 0,79 (p <0,001), classificada como concordância importante ou boa. Conclusão Este novo algoritmo demonstrou ser útil e capaz de identificar e diferenciar os tipos histoquímicos de metaplasia intestinal, além de possuir confiabilidade estatística

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The gastric mucosa is disturbed when breastfeeding is interrupted, and such early weaning (EW) condition permanently affects the differentiation of zymogenic cells. The aim of the study was to evaluate the immediate and long-term effects of EW on gastric cell proliferation, considering the molecular markers for cell cycle, inflammation, and metaplasia. Overall, we investigated the lifelong adaptation of gastric growth. Wistar rats were divided into suckling-control (S) and EW groups, and gastric samples were collected at 18, 30, and 60 days for morphology, RNA, and protein isolation. Inflammation and metaplasia were not identified, but we observed that EW promptly increased Ki-67-proliferative index (PI) and mucosa thickness (18 days). From 18 to 30 days, PI increased in S rats, whereas it was stable in EW animals, and such developmental change in S made its PI higher than in EW. At 60 days, the PI decreased in S, making the indices similar between groups. Spatially, during development, proliferative cells spread along the gland, whereas, in adults, they concentrate at the isthmus-neck area. EW pushed dividing cells to this compartment (18 days), increased PI at the gland base (60 days), but it did not interfere in expression of cell cycle molecules. At 18 days, EW reduced Tgfß2, Tgfß3, and Tgfbr2 and TßRII and p27 levels, which might regulate the proliferative increase at this age. We demonstrated that gastric cell proliferation is immediately upregulated by EW, corroborating previous results, but for the first time, we showed that such increased PI is stable during growth and aging. We suggest that suckling and early weaning might use TGFßs and p27 to trigger different proliferative profiles during life course.

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CD44 and CD133 have been considered as cancer stem cell (CSC) markers. Stem cell markers are rarely described in healthy stomach tissues. However, the clinicopathological and prognostic value of CD44 and CD133 in gastric cancer remains controversial. This study investigated the expression of CD44 and CD133 in gastric cancer and non-neoplastic gastric mucosa. We used samples of primary gastric adenocarcinomas (n = 69), metastatic lymph nodes (n = 30), intestinal metaplasia (n = 17), and histologically normal gastric tissues of surgical margins (n = 54). The expression of CD44 and CD133 were studied in samples by immunohistochemistry. Fisher's exact test and a logistic regression model were used in this study. CD44 expression was observed in 12% of samples with intestinal metaplasia, 20% with lymph node metastases, 22% with normal mucosa, to 30% of samples with primary tumors. Most of these positive tumors showed immunostaining in less than 4% of cancerous cells, mainly in the diffuse type. CD133 expression was observed in 7% (intestinal metaplasia) to 46% (normal mucosa). In the positive cases of cancer (24%), in most of them, less than 3% of cells were marked. CD44 and CD133 expression in the histologically normal gastric mucosa was restricted to the deeper regions of the gastric crypts at the level where stem cells and progenitor cells are usually found. CD44 and CD133 expression occurs in few gastric cancer cells, mainly in diffuse carcinomas, and are expressed in histologically normal gastric mucosae. None of the markers are specific for cancer and are also present in intestinal metaplasia and the normal mucosa.

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Sildenafil (SIL) has potential as an interesting gastroprotective drug. However, the pathways of its protective effect still needs to be clarified, and its use as a potential gastroprotective agent validated. This study aims to evaluate the effects of SIL via modulation of oxidative stress in a NSAID-induced gastric lesion model. Male Swiss mice were divided into six groups: control (CON, water), nonsteroidal anti-inflammatory drug (NSAID, water), proton pump inhibitor (PPI, 30 mg/kg of lansoprazole), SIL 5 (5 mg/kg), SIL 25 (25 mg/kg) and SIL 50 (50 mg/kg). The animals were treated by gavage (a single dose) after 24 hours of fasting, and gastric lesions were performed after 30 minutes, with indomethacin (40 mg/kg, by gavage). After 6h, the animals were killed and the stomach was removed to evaluate reactive oxygen species (ROS) production, oxidation of macromolecules, quantification of antioxidant enzymes, DNA fragmentation, apoptosis and macroscopic and histologic analysis of gastric lesions. SIL exerts a dose-dependent gastroprotective effect against NSAID-induced mucosal injury, also reducing cytoplasmic levels of ROS and consequent oxidative damage to macromolecules. In addition, SIL increases nitric oxide bioavailability, antioxidant enzymes and gastric cellular viability, as well as restoring important factors involved in gastroprotection. Our results demonstrate that different doses of SIL prevent indomethacin-induced gastric ulcer in mice via different, but complementary antioxidant, antigenotoxic and antiapoptotic mechanisms.

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Abstract Slowly digestible starch (SDS) and resistant starch (RS) associate with health benefits when present in the diet. This study aimed to evaluate ready-to-eat corn and cassava flours regarding their commercial presentation (dry or flaked), composition and in vitro digestibility of starch. Sixteen samples from Southern Brazil were procured in the market: eight dry cassava flours, six biju-type (flaked) corn flours and two biju-type cassava flours. Dry cassava flours had higher L* and lower b* values, and higher RS, relative crystallinity and viscosity peak values. Dry cassava flour partially preserves granular starch, as its processing involves lower drying temperatures and lower moisture of the pressed pulp. Dry cassava flours that had higher b* values also had higher rapidly digestible starch (RDS) levels, since higher temperatures are required in their production. Both biju-type flours showed the highest RDS values and no RS due to processing with elevated temperature and high moisture of the pressed pulp. In this study starch digestibility from the flours depended on processing, with minor influence of the raw material, fiber content and granulometry. The whiter and the smaller the granulometry of the dry cassava flours, the better they showed as potentially health benefiting.

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ABSTRACT Background: Helicobacter pylori harbouring cag-pathogenicity island (cagPAI) which encodes type IV secretion system (T4SS) and cagA virulence gene are involved in inflammation of the gastric mucosa. We examined all the 27 cagPAI genes in 88 H. pylori isolates from patients of different ethnicities and examined the association of the intactness of cagPAI region with histopathological scores of the gastric mucosa. Results: 96.6% (n = 85) of H. pylori isolates were cagPAI-positive with 22.4% (19/85) having an intact cagPAI, whereas 77.6% (66/85) had a partial/rearranged cagPAI. The frequency of cag2 and cag14 were found to be significantly higher in H. pylori isolated from Malays, whereas cag4 was predominantly found in Chinese isolates. The cag24 was significantly found in higher proportions in Malay and Indian isolates than in Chinese isolates. The intactness of cagPAI region showed an association with histopathological scores of the gastric mucosa. Significant association was observed between H. pylori harbouring partial cagPAI with higher density of bacteria and neutrophil activity, whereas strains lacking cagPAI were associated with higher inflammatory score. Conclusions: The genotypes of H. pylori strains with various cagPAI rearrangement associated with patients' ethnicities and histopathological scores might contribute to the pathogenesis of H. pylori infection in a multi-ethnic population.

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BACKGROUND: Helicobacter pylori harbouring cag-pathogenicity island (cagPAI) which encodes type IV secretion system (T4SS) and cagA virulence gene are involved in inflammation of the gastric mucosa. We examined all the 27 cagPAI genes in 88 H. pylori isolates from patients of different ethnicities and examined the association of the intactness of cagPAI region with histopathological scores of the gastric mucosa. RESULTS: 96.6% (n=85) of H. pylori isolates were cagPAI-positive with 22.4% (19/85) having an intact cagPAI, whereas 77.6% (66/85) had a partial/rearranged cagPAI. The frequency of cag2 and cag14 were found to be significantly higher in H. pylori isolated from Malays, whereas cag4 was predominantly found in Chinese isolates. The cag24 was significantly found in higher proportions in Malay and Indian isolates than in Chinese isolates. The intactness of cagPAI region showed an association with histopathological scores of the gastric mucosa. Significant association was observed between H. pylori harbouring partial cagPAI with higher density of bacteria and neutrophil activity, whereas strains lacking cagPAI were associated with higher inflammatory score. CONCLUSIONS: The genotypes of H. pylori strains with various cagPAI rearrangement associated with patients' ethnicities and histopathological scores might contribute to the pathogenesis of H. pylori infection in a multi-ethnic population.

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INTRODUCTION: Chronic gastritis is one of the most common diseases in the population. Several factors influence its appearance; however, the effect of high altitude has not been studied thoroughly. OBJECTIVE: To determine the association between the altitude of the residential area and chronic gastritis in outpatients of Peru. METHODS: Observational, analytical, and cross-sectional study. Secondary data analysis was conducted. The dependent variable was chronic gastritis, obtained from patient references, and verified in the medical history according to the pathological history mentioned during medical consultation. The independent variable was the altitude of the residential areas (categorized into low altitude, intermediate altitude, high and very high), and the secondary co-variables were age, sex, and time living at altitude. Generalized linear models were used to estimate prevalence ratios using Poisson family and city as a cluster. RESULTS: Of the 4263 patients studied, 63% were female; the median age was 42 years. The overall prevalence of chronic gastritis was 12,9%. There was an association with chronic gastritis and altitude of residence at the intermediate and high levels, but not at the very high; with an adjusted prevalence ratio of 1.52 (95% confidence interval, 1.03 to 2.23); 2.01 (1.55 to 2.60) and 1.12 (0.84 to 1.48), respectively. CONCLUSIONS: We found a significant association between chronic gastritis and intermediate and high altitude but not at very high, which could be explained by hypobaric hypoxia in altitude that could lead to gastric wall lesions and other socio-demographic variables.

INTRODUCCIÓN: La gastritis crónica es unas de las enfermedades más comunes en la población y varía por regiones. Existen diversos factores que influyen en su aparición. Sin embargo, no se ha estudiado a profundidad el efecto de la altura. OBJETIVOS: Determinar la asociación entre la zona altitudinal de residencia y gastritis crónica en pacientes ambulatorios de Perú. MÉTODOS: Estudio transversal analítico. Se realizó a través del análisis secundario de datos. La variable dependiente fue gastritis crónica, tomada del reporte del paciente y verificado en la historia clínica, según antecedentes patológicos mencionados durante consulta médica. La variable independiente fue la zona altitudinal de residencia (divida en baja altitud, altitud intermedia, elevada y muy elevada). Las covariables secundarias fueron edad, sexo y tiempo viviendo en altura. Se realizaron modelos lineales generalizados para estimar razones de prevalencias, usando familia Poisson y ciudad como clúster. RESULTADOS: De los 4263 pacientes estudiados, 63% fue del sexo femenino; la mediana de la edad fue de 42 años. La prevalencia global de gastritis crónica fue 12,9%. Hubo asociación con gastritis crónica y altura de residencia a nivel intermedio, elevado, pero no con muy elevado, con una razón de prevalencia ajustada de 1,52 (intervalo de confianza 95%: 1,03 a 2,23); 2,01 (1,55 a 2,60) y 1,12 (0,84 a 1,48), respectivamente. CONCLUSIONES: Se encontró una asociación significativa entre gastritis crónica y altitud intermedia y elevada, pero no en muy elevada. Esto se explicaría por la hipoxia hipobárica en alturas, que podría conllevar lesiones en la pared gástrica, la adaptación de los peruanos a las alturas y por otras variables sociodemográficas.

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