Guillermo Zarama

Helicobacter pylori and gastric carcinoma: Serum antibody prevalence in populations with contrasting cancer risks

This investigation examined the correlation between Helicobacter pylori (HP) infection, as reflected in immunoglobulin G serum antibodies, and the risk of gastric cancer. Serum samples were obtained from populations with contrasting gastric cancer risks. the highest prevalence of HP infection, 93%, was observed in the adult population at highest gastric cancer risk, the residents of Pasto, Colombia. in the lower risk Colombian city of Cali, a 63% overall prevalence rate was found. Both children and adults were sampled in New Orleans, Louisiana, where gastric cancer rates are high for blacks but not for whites. the prevalence of HP infection was significantly higher in black than in white adults, 70% versus 43%, P = 0.0001. A higher prevalence was also detected in black compared with white children, 49% versus 32%, P = 0.01; however, an even greater disparity was noted when comparing children from two hospitals, regardless of race, which serve different socioeconomic groups. A prevalence rate of 54% was found at Charity Hospital compared with 24% (P = 0.0001) at Childrens Hospital. Our findings indicate that socioeconomic conditions, known to influence gastric cancer risk, are also important determinants of HP infection.

A randomized clinical trial to determine the efficacy of regimens containing clarithromycin, metronidazole, and amoxicillin among histologic subgroups for Helicobacter pylori eradication in a developing country.

Background: Most treatments deemed effective for Helicobacter pylori eradication in developed countries are less effective in developing countries. Regimens containing clarithromycin, metronidazole, and amoxicillin seem efficacious despite antibiotic resistance, and may be a viable option in developing countries.

Sodium intake and gastric cancer.

SummaryTo test the hypothesis that excessive intake of sodium chloride is a factor in gastric carcinogenesis, urinary excretion of sodium and creatinine was measured in Colombian subjects. Age, sex, weight, and height regression slopes for creatinine excretion were more similar in Colombia than in other countries. Sodium/creatinine (S/C) ratios correlated with 24-h urinary excretion of sodium revealed higher sodium excretion in populations with higher gastric cancer rates. The S/C ratios were not affected by circadial rhythms, making it possible to use single urine samples to investigate interpopulation differences in sodium excretion.

Mutagenic activity of nitrosated foods in an area with a high risk for stomach cancer

In a search for possible sources of mutagens in human foods, a study was made of six common foods in the diet of a population at high risk for gastric cancer (in Nariño, Colombia). No mutagenic activity was demonstrated in nonnitrosated foods. After nitrosation, only one of the foods, fava beans, demonstrated a mutagenic effect. This effect was direct and concentrated in the germ and pulp of the beans.