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Mecanismos de ação relacionados à atividade antiúlcera de Kalanchoe pinnata (Lam.) Pers. (Crassulaceae) / Mechanisms of action underlying antiulcer activity of Kalanchoe pinnata (Lam.) Pers. (Crassulaceae).Gonçalves, Flávia Sobreira Mendonça 18 September 2017 (has links)
Kalanchoe pinnata (Lam.) Pers. (Crassulaceae) é uma espécie muito empregada na medicina tradicional no Brasil e em outras partes do mundo, especialmente Índia, países da África e China. É indicada popularmente para diversos fins incluindo o tratamento de úlceras gástricas. A análise fitoquímica revelou a presença de vários constituintes, em especial os flavonoides. O tratamento de úlcera gástrica convencional apresenta diversos efeitos colaterais e, na maioria das vezes, não evita a recidiva da lesão. Dessa maneira, é interessante encontrar uma terapêutica mais segura e efetiva. Com o objetivo de avaliar a segurança, foi realizado ensaio de citotoxicidade do extrato bruto, in vitro, com valor de IC50 igual a 0,926 mg/mL, sendo possível predizer um valor de LD50 (1341,46 mg/kg). Já em relação ao ensaio de citotoxicidade, in vitro, da fração acetato de etila não foi encontrado um valor de IC50. Resultados de fototoxicidade, in vitro, mostraram que o extrato bruto e fração acetato de etila de K. pinnata não possuem potencial fototóxico. A contagem microbiana na droga vegetal para bactérias aeróbias/mesófilas foi de 6,9 x 104 UFC/g e a contagem de bolores e leveduras foi de 2,4 x 103 UFC/g, ambos valores dentro do limite estabelecido pela OMS. Análise de endotoxinas também foi realizada para o extrato bruto (<4,0.105 UE/kg) e fração acetato de etila (<2,7.105 EU/kg) de K. pinnata. Referente à fitoquímica, diversos flavonoides foram identificados no extrato bruto e fração acetato de etila de K. pinnata. Paralelamente ao estudo fitoquímico foi verificado que a atividade gastroprotetora do extrato bruto envolve a ação das prostaglandinas e grupamentos sulfidrila. Já o mecanismo de gastroproteção da fração acetato de etila é dependente de prostaglandinas e óxido nítrico. A atividade cicatrizante do extrato bruto de K. pinnata também foi avaliada. De acordo com os resultados macroscópicos, as doses de 200mg/kg e 400 mg/kg reduziram a área de lesão, com uma taxa de 33% e 39%, respectivamente, após 7 dias de tratamento (p<0,05). Análise histológica dos grupos tratados com o extrato bruto (200 e 400 mg/kg) indicou melhor recuperação da lesão, verificada pela regeneração da mucosa gástrica e pelo restabelecimento da arquitetura glandular. As enzimas antioxidantes (catalase, superóxido dismutase e glutationa peroxidase) e a expressão de VEGF foram avaliadas no mecanismo de cicatrização de úlceras gástricas. Os resultados mostraram que a atividade antiulcerogênica foi mediada pela ação antioxidante da enzima SOD. Não foi evidenciado in vivo o aumento da expressão de VEGF e nem o sequestro do radical peroxil nos animais tratados com o extrato bruto. Os resultados dos ensaios in vitro (ORAC) mostraram uma maior capacidade de sequestro de radicais peroxil da fração acetato de etila (1192,35 ± 112,61 µmol equivalente de Trolox/g de amostra seca) quando comparado com o extrato bruto (431,32 ± 7,17 µmol equivalente de Trolox/g de amostra seca). A atividade anti Helicobacter pylori também foi avaliada, no entanto, o extrato bruto não apresentou atividade anti H.pylori. Ademais, o extrato bruto demonstrou um potencial anti-inflamatório, pois foi observada uma redução nos níveis de TNF-α e L-selectina, após o tratamento em neutrófilos estimulados com LPS. Analisando os resultados sugere-se que K. pinnata possui um potencial terapêutico no combate de úlceras gástricas e possivelmente, anti-inflamatório, sendo que os flavonoides podem estar relacionados com o efeito biológico observado. / Kalanchoe pinnata (Lam.) Pers. (Crassulaceae) is a commonly used species in traditional medicine in Brazil and in other parts of the world, especially India, Africa and China, for the treatment of various diseases, including gastric ulcers. Phytochemical analysis revealed the presence of several constituents in this plant, especially flavonoids. The available pharmaceutical products to treat peptic ulcer have several side effects and, in most cases, do not prevent recurrence of the gastric lesions. Therefore, it is important to find a safer and more effective therapy. In order to evaluate safety, the in vitro cytotoxicity assay of crude extract from K. pinnata was performed. The IC50 value was 0,926 mg/mL corresponding to LD50 value (1341, 46 mg/kg). It was not determined IC50 value in vitro cytotoxicity assay for ethyl acetate fraction from K. pinnata. Neither the crude extract nor ethyl acetate fraction from K. pinnata showed phototoxicity. Microbial counting was performed on the K. pinnata-based drug in order to investigate microbiological contamination. The microbial count for aerobic / mesophilic bacteria was 6.9 x 104 CFU/g, and yeast count was 2.4 x 103 CFU/g, both values in agreement with the limits established by WHO. Endotoxin analysis was also performed for the crude extract (<4,0.105 UE/kg) and for ethyl acetate fraction (<2,7.105 UE/kg) from K. pinnata. In the phytochemical analysis several flavonoids were identified in the crude extract and ethyl acetate fraction of K. pinnata. In parallel to the phytochemical study, it was verified that the gastroprotective activity of the crude extract of K. pinnata involved prostaglandins and sulfhydril compounds. On the other hand, the mechanism of gastroprotection of the ethyl acetate fraction of K. pinnata is dependent on prostaglandins and nitric oxide. The healing activity of the crude extract of K. pinnata was also evaluated. According to the macroscopic results the dose of 200 mg/kg and 400mg/kg reduced the injury area, with a rate of 33% and 39%, respectively, after 7 days of treatment (p <0.05). Histological analysis showed regeneration of the gastric mucosa and re-establishment of the glandular architecture in groups treated with the crude extract (200 and 400 mg/kg). Antioxidant enzymes (catalase, superoxide dismutase and glutathione peroxidase) and VEGF expression were evaluated in the mechanism of gastric ulcer healing. The results showed that the antiulcerogenic activity was mediated by SOD. It was not demonstrated an increase in VEGF expression and nor in the in vivo sequestration of the peroxyl radical in the animals treated with crude extract. The results of in vitro assay (ORAC) showed a greater sequestering of peroxyl radical to the ethyl acetate fraction (1192,35 ± 112,61 µmol equivalent of Trolox/g of ethyl acetate fraction) when compared to the crude extract (431,32 ± 7,17 µmol equivalent of Trolox/g of crude extract) of K. pinnata. The anti Helicobacter pylori activity was also evaluated; however, the crude extract did not show anti H. pylori activity. However, the crude extract of K. pinnata demonstrated an anti-inflammatory potential, because TNF-α and L-selectin levels were reduced after treatment in LPS-stimulated neutrophils. The analysis of the results suggests that K. pinnata has a therapeutic potential against gastric ulcers and possible anti-inflammatory properties, and the flavonoids may be linked to the biological effect.
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Efeito do comprimento de alça biliar e alimentar da derivação gástrica em Y de Roux de controle do diabetes mellitus do tipo 2 em pacientes com Índice de Massa Corporal (IMC) 50 Kg/m2 / Effect of biliary and alimentary limbs lengths of the Roux-en-Y gastric bypass in the control of type 2 diabetes mellitus in patients with Body Mass Index (BMI) 50 kg/m2Pinheiro Filho, José Carlos da Silveira 11 November 2008 (has links)
Introdução: Pacientes com Índice de Massa Corporal (IMC) maior ou igual 50kg/m2 podem atingir perda de peso adequada após derivação gástrica em Y de Roux de alça longa. No entanto, esses pacientes podem necessitar de alças intestinais mais longas para controle ou melhora de doenças associadas à obesidade, como o diabetes mellitus do tipo 2. Casuística e métodos: Estudo prospectivo de 100 pacientes com Índice de Massa Corporal (IMC) maior ou igual 50kg/m2 divididos em 2 grupos similares quanto ao sexo, idade e tipo de doença associada. Todos os pacientes foram submetidos à derivação gástrica em Y de Roux por laparoscopia. No grupo 1, o comprimento da alça biliar foi de 50 cm e o da alça alimentar, de 150 cm. No grupo 2, o comprimento da alça biliar foi de 100 cm e o da alça alimentar, de 250 cm. Resultados: O seguimento foi de 48 meses. O diabetes mellitus do tipo 2 foi controlado em 58% dos pacientes do grupo 1 e em 93% dos pacientes do grupo 2 no pós-operatório (p<0,05). A perda do excesso de peso foi mais rápida no grupo 2, mas semelhante nos 2 grupos estudados aos 48 meses, sem diferença estatística. Conclusões: Pacientes com Índice de Massa Corporal (IMC) maior ou igual 50kg/m2 submetidos à derivação gástrica em Y de Roux com alças biliar e alimentar mais longas apresentaram maior controle de diabetes mellitus do tipo 2 do que pacientes com alças mais curtas. / Background: Patients With Body Mass Index (BMI) > or = 50kg/m2 may achieve adequate weight loss with long limb RYGB. These patients, however, might need longer intestinal limbs to control co-morbidities such as type 2 diabetes. Methods: A prospective study of 100 super-obese patients who were divided in 2 similar groups regarding sex, age, and number of co-morbidities. All were submitted to laparoscopic RYGB. In group 1, length of biliary limb was 50 cm and length of Roux limb was 150 cm. In group 2, length of biliary limb was 100 cm and of Roux limb was 250 cm. Results: Follow-up was 48 months. Diabetes was controlled in 58% of group 1 patients and in 93% of group 2 patients (p<0.05). Excess weight loss was faster in group 2, but was similar in both groups at 48 months, with no statistical difference. Conclusions: Super-obese patients with longer biliary and Roux limbs achieved greater type 2 diabetes control.
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The effects of variable dose methotrexate infusion in the laboratory ratDodridge, M. E. (Miles Edward) January 1987 (has links) (PDF)
Bibliography: leaves 186-211.
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The relationship between disturbed gastric motor function and enteral nutrition in critically ill patients.Nguyen, Nam Quoc January 2008 (has links)
Delayed gastric emptying, that manifests clinically as intolerance to enteral feeding, occurs in over 50% of critically ill patients and has a major impact on patient morbidity and mortality. Despite the recognition that the proximal stomach has a major role in gastric emptying of liquids, only the motor activity of the antro-pyloro-duodenal region has been evaluated in detail. In addition, many of the proposed risk factors for the gastric dysmotility, particularly a prior history of diabetes mellitus, have not been evaluated formally but have been extrapolated from data from non-critically ill patients. The currently available prokinetic drugs, erythromycin and metoclopramide, are considered to be the first line treatment for feed intolerance. However, neither data comparing the effectiveness of these agents nor the data on the effects of combination of therapy in the treatment of feed intolerance are available. The aims of this thesis were, therefore, to examine: (i) proximal gastric motor activity and the association between proximal and distal motility; (ii) the relationship between entero-gastric humoral responses to nutrients, gastric emptying and feed intolerance; (iii) the impact of admission diagnoses, choice of sedations, timing of initiation of feeding, and pre-existing history of diabetes mellitus on gastric emptying and feed intolerance; and (iv) the efficacy of erythromycin, metoclopramide and combination of these drugs in treatment of feed intolerance in critically ill patients. The current thesis indicates that motor activity is impaired in multiple regions of the stomach in the critically ill. When compared to healthy humans, proximal gastric relaxation was prolonged and fundic wave activity was educed during small intestinal nutrient infusion in critically ill patients. In addition, simultaneous assessment of proximal and distal gastric motility demonstrated a possible disruption of the motor integration between the proximal and distal stomach. In light of the recent data that suggested a significantly greater proportion of meal distributed proximally in critically ill patients with delayed gastric emptying (Nguyen, et al. 2006), the disruption of the gastric motor integration and the prolonged gastric relaxation in response to duodenal nutrients may play a significant role in the pathogenesis of slow gastric emptying during critical illness, especially as liquid formulae. The entero-gastric hormonal feedback responses were also disturbed during critical illness. Both fasting and duodenal nutrient-stimulated plasma CCK and PYY concentrations were significantly higher in critically ill patients, particularly those who did not tolerated gastric feeds. The rate of gastric emptying of a liquid meal was inversely related to both fasting and postprandial plasma CCK and PYY concentrations, supporting the potential role of plasma CCK and PYY in the pathogenesis of gastric dysmotility in critically ill patients. Admission diagnosis, choice of sedative drug and blood glucose control but not the timing of enteral feeds were important factors for delayed gastric emptying and feed intolerance in these patients. In particular, delaying enteral feeding by 4 days had no impact on the rate of gastric emptying, intra-gastric meal distribution, or plasma CCK and PYY concentrations. Contrary to traditional belief, critically ill patients with a pre-existing diagnosis of type 2 DM have only a minor disturbance to the proximal stomach, a relatively normal gastric emptying and are at no higher risk of feed intolerance than those without DM, suggesting the presence of pre-existing DM 2 in critically ill patients should not influence the standard practice of gastric feeding. Therapeutically, short-term treatment with low dose erythromycin was more effective than metoclopramide, but the effectiveness decreased rapidly overtime at similar rate as observed with metoclopramide. In patients who failed to response to either agent, treatment with both agents was highly effective in re-establishing feeding success. The use of combination therapy as the initial treatment for feed intolerance was also more effective than erythromycin alone and had less tachyphylaxis. Treatment with erythromycin and metoclopramide, either as a single agent or in combination did not associated with major cardiovascular adverse side effects. Although diarrhoea was a common side effect and was highest with combination therapy, it was not associated with Clostridium difficile infection and settled quickly after the cessation of the prokinetic therapy. In summary, the work performed in the current thesis has provided substantial insights into the understanding of the nature, risk factors, pathogenesis and treatment of disturbed gastric motor function in critically ill patients. Not only do these findings stimulate further research into the mechanisms responsible for gastric dysmotility in critical illness, they also lead to the development of new strategies for optimizing the management of feed intolerance. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1320667 / Thesis (Ph.D.) -- University of Adelaide, School of Medicine, 2008
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Intestinal peptides and ethnic differences in insulin secretionHiggins, Paul B. January 2006 (has links) (PDF)
Thesis (Ph. D.)--University of Alabama at Birmingham, 2006. / Title from first page of PDF file (viewed Feb. 22, 2007). Includes bibliographical references (p. 92-107).
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Characterization of Endocrine Cells and Tumours in the StomachTsolakis, Apostolos V. January 2008 (has links)
Enterochromaffin-like (ECL) and ghrelin cells, in the human gastric mucosa and in gastric endocrine tumours (GETs), were subclassified with respect to immunohistochemical reaction vs. vesicular monoamine transporter 2 (VMAT-2), ghrelin/obestatin, and histidine decarboxylase (HDC). The immunohistochemical expression of ghrelin/obestatin and HDC in GETs was related/correlated to plasma ghrelin/obestatin and urinary methyl imidazole acetic acid (U-MeImAA) excretion respectively, with the intention of identifying markers for these tumour types. ECL cells in the gastric mucosa appear either with VMAT-2 only, or with HDC immunoreactivity only, or they can express both proteins; but in GETs the transporter protein and the enzyme were almost always co-expressed in the same cells. Furthermore, ghrelin and obestatin were co-localized in the same cells in the gastric mucosa and in the tumours. In the gastric mucosa, occasional ghrelin/obestatin cells expressed VMAT-2, but in GETs these proteins were always co-localized. Ghrelin expressing cells were non-immunoreactive to HDC. Plasma ghrelin/obestatin concentrations remained low in patients with GETs, irrespective of the relative incidence of these cells in the mucosa and in tumours. The plasma values were not related/correlated to various clinico-pathological parameters. A malignant ghrelinoma was however an exception. The tumour released high total and active ghrelin concentrations into the blood circulation. The patient suffered from diarrhoea, hypothyroidism and diabetes mellitus, but it is not clear if these conditions were due to hyperghrelinaemia. The excretion U-MeImAA was increased in a few patients with GETs, but this increase was not always related to clinical symptoms. In conclusion, ECL cells are an heterogeneous group according to VMAT-2 and HDC immunoreactivity. Ghrelin and obestatin are expressed in the same cells in the gastric mucosa, and a few of these cells display VMAT-2 immunoreactivity. Ghrelinoma is a new gastric tumour entity.
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Histopathological Study on the Prognosis of pT2 Gastric CancerKONDO, TATSUHEI, KAMEI, HIDEO, TERABE, KEISUKE 03 1900 (has links)
No description available.
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The effect of nonylphenol and bisphenol A on calcium signaling and viability in cultured cellsKuo, Chun-Chi 23 June 2010 (has links)
Environmental chemicals may affect human health by disrupting endocrine function. Many of the endocrine disrupting chemicals (EDCs) are estrogens or estrogen-like molecules that have been classified as environmental estrogens or xenoestrogens (XEs). XEs include endosulfan, chlordance, nonylphenol, bisphenol A, octylphenol, and coumestrol, etc. Although these compounds have wide structural diversity, but all have in common the and/or other hydrophobic components. Many studies have shown that XEs affect cell viability. For instance, Nonylphenol is used in surfactants or plasticizers and bisphenol A (4, 4¡¦-isopropylidene-2-diphenol) is used as protective coatings on food containers and for composites and sealants in dentistry. Most previous studies have focused on the toxicity of XEs on development process and reproductive system, especially in aquatic ecosystems. Thus, the effects of these two environmental chemicals on the toxicological effect are still controversial.
The aim of this study is to investigate the molecular mechanisms of nonylphenol and bisphenol A in induction of cell death in human gastric cancer (SCM-1) cells and Madin Darby canine renal tubular (MDCK) cells. First, WST-1 reduction assays and propidium iodide-staining assay were used to determine cell viability and apoptosis in the present of nonylphenol and bisphenol A. Furthermore, we will use immunoblotting to measure the activity of apoptotic markers caspase-3, mitogen-activated protein kinases (MAPKs) to survey how nonylphenol affects apoptotic pathways. Besides, I will explore bisphenol A whether induces cell death and the mechanisms underlying the [Ca2+]i rise in MDCK cells. The results may be helpful for understanding the pharmacological and toxicological effects of these two environmental chemicals in cells from important organs.
Results showed that nonylphenol caused apoptosis via the activation of caspase-3 in cultured human gastric cancer (SCM-1) cells. Although nonylphenol could activate the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK), only SB203580 (a p38 MAPK inhibitor) partially prevented cells from apoptosis. Nonylphenol was also found to induce [Ca2+]i increases and pretreatment with BAPTA/AM, a Ca2+ chelator, prevented nonylphenol-induced [Ca2+]i increases, and protect cells from death. These results suggest that nonylphenol induced apoptosis via a Ca2+- and p38 MAPK-dependent pathway.
On the other hand, the effect of the environmental contaminant bisphenol A on cytosolic free Ca2+ concentrations ([Ca2+]i) in Madin Darby canine kidney (MDCK) cells is unclear. This study explored whether bisphenol A changed basal [Ca2+]i levels in suspended MDCK cells by using fura-2 as a Ca2+-sensitive fluorescent dye. Bisphenol A at concentrations between 50-300 £gM increased [Ca2+]i in a concentration-dependent manner. The Ca2+ signal was reduced partly by removing extracellular Ca2+. Bisphenol A induced Mn2+ influx, leading to quench of fura-2 fluorescence suggesting Ca2+ influx. This Ca2+ influx was inhibited by phospholiapase A2 inhibitor aristolochic acid, store-operated Ca2+ channel blockers nifedipine and SK&F96365; and protein kinase C inhibitor GF109203X. In Ca2+-free medium, pretreatment with the mitochondrial uncoupler carbonylcyanide m-chlorophenylhydrazone (CCCP) and the endoplasmic reticulum Ca2+ pump inhibitors thapsigargin or 2,5-di-tert-butylhydroquinone (BHQ) inhibited bisphenol A-induced Ca2+ release. Conversely, pretreatment with bisphenol A abolished thapsigargin (or BHQ)- and CCCP-induced [Ca2+]i rise. Inhibition of phospholipase C with U73122 abolished bisphenol-induced [Ca2+]i rise. Bisphenol A caused concentration-dependent decrease in cell viability via apoptosis in a Ca2+-independent manner. Collectively, in MDCK cells, bisphenol A induced [Ca2+]i rises by causing phospholipase C-dependent Ca2+ release from the endoplasmic reticulum and mitochondria and Ca2+ influx via phospholipase A2-protein kinase C-sensitive store-operated Ca2+ channels.
Key words: calcium, apoptosis, human gastric cancer cells (SCM-1), Madin Darby canine kidney (MDCK), nonylphenol, bisphenol A.
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POSTOPERATIVE FUNCTION FOLLOWING RADICAL SURGERY IN GASTRIC AND COLORECTAL CANCER PATIENTS OVER 80 YEARS OF AGE : AN OBJECTION TO “AGEISM”ODA, KOJI, KUROIWA, KOJIRO, AMEMIYA, TAKESHI, ANDO, MASAHIKO, FUKATA, SHINJI 08 1900 (has links)
No description available.
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Genetic polymorphism in interleukin-1B and interleukin-1 receptor antagonist on gastric cancer and duodenal ulcerLi, Chin-Ni 10 July 2002 (has links)
Interleukin-1 (IL-1) is a prototypic multifunctional cytokine. IL-1 family include interleukin-1 a (IL-1 a), interleukin-1b (IL-1 b) and interleukin-1 receptor antagonist (IL-1 Ra). IL-1 b is the archetypeal pleiotropic cytokine which have been produced by many cells and exerting its biological effects on almost all cell types. IL-1 b is the most potent of known agents that are gastric cytoprotective, antiulcer, antisecretory and an inhibitor of gastric emptying. IL-1 Ra competes with IL-1 b for cell surface receptor occupancy. Host genetic factors that affect interleukin-1 (IL-1) have been reported to influence the susceptibility of Caucasians to gastric cancer. Whether Asians have the same genetic susceptibility remains unclear. In this study, the genetic associations of IL-1B and IL-1RN polymorphisms with gastric cancer and duodenal ulcer in Taiwan were evaluated.
Genomic DNA from 140 unrelated Taiwanese patients with gastric adenocarcinoma, 94 with duodenal ulcer and 165 ethically matched healthy controls was typed for polymorphisms at positions ¡V31, -511, and +3954 in the IL-1B gene, and the variable number of tandem repeats polymorphisms in intron 2 of the IL-1RN gene.
The allele frequencies of IL-1RN 2R in gastric cancer cases were much higher than those in healthy controls (9% vs. 3%, p = 0.781). The allele frequencies of IL-1B ¡V31, IL-1B ¡V511 and IL-1B +3954 did not differ. An increased risk of the development of intestinal type gastric carcinoma was found in IL-1RN 2R carriers with an odds ratio (OR) of 4.06 (95% confidence interval [CI]: 1.68 ¡V 9.79, p-value=0.085). And another increased risk of the development of diffuse type gastric carcinoma was found in IL-1RN 2R carriers with an odds ratio (OR) of 3.15 (95% confidence interval [CI]: 1.16 ¡V 8.56, p-value=0.061). A significant association was found in IL-1RN 2R/4R genotype and the risk of the development of duodenal ulcer, with an odds ratio (OR) of 2.57 (95% CI: 1.03 ¡V 6.38, p = 0.292). No significant relationship was noted in duodenal ulcer patients with IL-1B genotype examed in this study. Additionally, a synergistic interaction between blood type A and IL-1 RN 2R carriers existed in gastric cancer patients (OR= 4.51; 95% CI: 1.20 ¡V 16.88, p-value=0.516). The synergistic interaction was even stronger between blood type O and IL-1 RN 2R carriers of duodenal ulcer patients (OR= 10.3; 95% CI: 2.10 ¡V 50.61, p-value=0.160).
In conclusion, the genetic polymorphisms of IL-1RN 2R and blood type A are associated with the development of gastric cancer. The genetic polymorphisms of IL-1RN 2R and blood type O are associated with the development of duodenal ulcer.
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