PubMed Health⌕ Search

Biomedical subjects

N Muñoz

Publications and source records attributed to N Muñoz.

At least 163 records · Page 9Linked to original sources
PubMed1985

No effect of riboflavine, retinol, and zinc on prevalence of precancerous lesions of oesophagus. Randomised double-blind intervention study in high-risk population of China.

A randomised double-blind intervention trial was carried out in Huixian, Henan Province, People's Republic of China, to determine whether combined treatment with retinol, riboflavine, and zinc could lower the prevalence of precancerous lesions of the oesophagus. 610 subjects in the age group 35-64 were randomised to receive once a week the active treatment (15 mg [50 000 IU] retinol, 200 mg riboflavine, and 50 mg zinc) or placebo. Both at entry to the study and at the end of the treatment, 13.5 months later, the subjects were examined, with an emphasis on signs of vitamin A and riboflavine deficiences, and riboflavine, retinol, beta-carotene, and zinc levels were measured. Compliance was excellent. The final examination, on 567 (93%) subjects, included oesophagoscopy and at least two biopsies. The intervention did not affect the prevalence of oesophageal lesions: after one year, the prevalence of oesophagitis with or without atrophy or dysplasia was 45.3% in the placebo group and 48.9% in the vitamin/zinc treated group.

Adult↗
PubMed1984

Precursor lesions of oesophageal cancer in a low-risk population in China: comparison with high-risk populations.

An endoscopic survey was undertaken in Jiaoxian, People's Republic of China, a population at low risk for oesophageal cancer, to determine the prevalence of precancerous lesions of the oesophagus, and this rate was compared with the prevalence observed previously in high-risk populations in Iran and Linxian, China. The study involved 252 subjects whose exposure to suspected risk factors was determined by a questionnaire and all of whom underwent physical examination and oesophagoscopy, including cytology and biopsy. Chronic oesophagitis, with endoscopic and histologic characteristics similar to those observed in the high-risk populations of Iran and Linxian, was found in 28% of the study subjects compared to 80% in Iran and 65% in Linxian. Oesophagitis accompanied by atrophy of the epithelium was found in 0.4% compared to 10.5% in Iran and 10.8% in Linxian. No case of dysplasia was diagnosed in Jiaoxian while this condition was diagnosed in 4% of the subjects examined in Iran and in 8% of those in Linxian. The findings suggest that these lesions are in fact precancerous. Vitamin analysis showed that riboflavin deficiency was widespread in Jiaoxian, as in Iran and Linxian, but was more severe in Linxian than in Jiaoxian. No significant difference was found in the mean levels of retinol, beta-carotene and zinc between the two populations.

Adolescent↗
PubMed1984

Endoscopic features of suspected precancerous lesions in high-risk areas for esophageal cancer.

A high prevalence of a chronic form of esophagitis was found during two endoscopic surveys carried out in high-incidence areas of esophageal cancer in 430 subjects from Iran, and in 527 individuals from Linxian, Peoples Republic of China, selected from the general population. This high prevalence was present even in the younger age groups. The lesion does not seem to be related to gastro-histological correlation, available for all cases examined, confirmed the chronic nature of the lesion. dysplasia was found in 3 to 8 per cent of the cases. Overall, 21 esophageal cancers were diagnosed, most in a very early phase, and some only at histology. A follow-up of 20 cases after one year, showed the progression of this chronic lesion to cancer in 4 cases. The data available suggest the precancerous nature of the lesion in these high-risk populations.

Adolescent↗
PubMed1982

Precursor lesions of oesophageal cancer in high-risk populations in Iran and China.

To determine the prevalence of precursor lesions of oesophageal cancer in Linxian, People's Republic of China, which has an extremely high incidence of oesophageal cancer, 527 subjects were interviewed by a questionnaire about exposure to suspected risk factors. They also underwent oesophagoscopy, cytology, and biopsy. 84% had a chronic oesophagitis which had similar endoscopic and histological characteristics to that reported in Iran. The oesophagitis was accompanied by atrophy of the epithelium in 10% of these subjects and by dysplasia in 8%. Re-examination of 20 selected subjects 1 year later showed progression of the oesophagitis to atrophy and dysplasia in 4 individuals and to cancer in 4 others. The surveys in Iran and China suggest that the natural history of oesophageal cancer starts with an oesophagitis which, in a few individuals, progresses to atrophy and dysplasia of the epithelium and finally to cancer. Thermal injury resulting from the drinking of very hot beverages, physical injury caused by ingesting very coarse food, and deficiencies of riboflavine, vitamin A, and zinc are proposed as risk factors for these precursor lesions.

Adult↗
PubMed1979

Oesophageal lesions in northern Iran: a premalignant condition?

An endoscopic survey was undertaken in northern Iran to identify and determine the prevalence of possible precancerous lesions of the oesophagus. 218 men and 212 women, aged between 15 and 70 years, were included in the study. Oesophagoscopies were done on all 430 subjects and biopsies on 418. A chronic oesophagitis, involving mainly the middle and lower thirds of the oesophagus, was found in 80% of the subjects, and the frequency was very high even in the younger age-groups. Clinically and histologically the oesophagitis in this rural population was different from that observed in the low-risk areas of Europe and the United States, where oesophagitis is often associated with reflux. Dysplasia was diagnosed in 16 subjects and invasive carcinoma in 11. The very high prevalence of chronic oesophagitis in northern Iran, where a high incidence of oesophageal cancer has also been reported, suggests that these two lesions are associated.

Adolescent↗
PubMed1978

Infectious mononucleosis and Hodgkin's disease.

A cohort of 9,454 patients with infectious mononucleosis, serologically confirmed, was followed up to determine their risk of developing lymphoproliferative diseases. A total of 1,759 patients was identified in Scotland from 1959 to 1971 and 7,695 in Sweden from 1952 to 1970. The cancer cases were identified by matching the list of patients with infectious mononucleosis against a list of patients with lymphoma, nasopharyngeal and colon carcinomas registered through 1972 in Sweden and through 1973 in Scotland. A four-fold increase in risk was found for Hodgkin's disease based on 7 cases observed against 1.8 expected. Most of the excess cases of Hodgkin's disease occurred within three years of the diagnosis of infectious moonucleosis and among females. These results are similar to those of four other cohort studies and it is concluded that a positive association exists between infectious mononucleosis and Hodgkin's disease. Several explanations of this association were evaluated. Firstly, it may be that a very small proportion of persons who are in the course of developing Hodgkin's disease are temporarily misdiagnosed as having infectious mononucleosis. Secondly, infectious mononucleosis may increase the susceptibility to a factor which causes or promotes the development of Hodgkin's disease. Thirdly, infectious mononucleosis and Hodgkin's disease may share a common aetiology. Arguments in favour of, or against, each of these explanations are presented.

Adolescent↗
PubMed1976

Model systems for cervical cancer.

The evidence suggesting that a venereally transmitted virus and/or hormonal factors are involved in the etiology of cervical cancer is reviewed. The animal models used to test the oncogenic potential of these two types of agents are also discussed.

Animals↗
PubMed1975

Antibodies to herpesviruses in patients with cervical cancer and controls.

The indirect immunofluorescent test was used to detect antibodies to herpesviruses types 1 and 2, cytomegalovirus and EBV in sera from patients with cervical carcinoma, condyloma acuminatum and controls from Cali, Colombia, and a control group from the USA. No significant differences were found in the prevalence of antibodies to viral capsid antigens of HSV-1 and CMV among the groups studied. However, titres for HSV-2 were higher in the three groups from Cali (cervical carcinoma, condyloma and controls) than in the control groups from USA. High EBV antibody titres (VCA and early antigens) were found in the three groups from Cali. Antibodies to early antigens of CMV were detected in a sub-sample of the subjects and with higher frequency in patients with cervical cancer. The significance of these findings is discussed.

Antibodies, Viral↗