PubMed Health⌕ Search

Biomedical subjects

C Braga

Publications and source records attributed to C Braga.

At least 37 records · Page 2Linked to original sources
PubMed1998

Differences in the frequency of cytokine-producing cells in antigenemic and nonantigenemic individuals with bancroftian filariasis.

Individuals with clinical manifestations of lymphatic filariasis may be currently infected or not. Twenty-five individuals from a Wuchereria bancrofti-endemic area of Brazil were classified as being asymptomatic microfilaremic individuals, antigenemic individuals with clinical filariasis, or nonantigenemic individuals with clinical filariasis. Intracellular cytokine staining of mitogen-stimulated peripheral blood mononuclear cells (PBMC) showed that the frequency of either gamma interferon (IFN-gamma)- or interleukin-4 (IL-4)-producing cells was higher in the nonantigenemic individuals with clinical filariasis than in the asymptomatic microfilaremic individuals (geometric means, 22.1 versus 10.7% [P = 0.02] and 2.9 versus 1.4% [P = 0.01], respectively). When the asymptomatic microfilaremic individuals and antigenemic individuals with clinical filariasis were grouped together to constitute all actively infected individuals, the frequency of IFN-gamma-producing cells was also lower than in the nonantigenemic individuals with clinical filariasis (P = 0.04). Likewise, the frequency of IL-4-producing cells in the actively infected individuals was also lower than in the nonantigenemic individuals with clinical filariasis (P = 0.02). No differences in the frequency of IFN-gamma-, IL-4-, or IL-5-producing cells in purified CD4 T lymphocytes were found among the groups. These findings suggest that the presence of antigenemia, which is an indicator of current active infection, is closely associated with the frequency of IFN-gamma- and IL-4-producing cells in lymphatic filariasis. The differences found in the frequency of cytokine-producing cells among the three groups appear to be due to a subset of cells other than CD4 T cells.

Adolescent↗
PubMed1998

Hormone replacement therapy and risk of colon and rectal cancer.

The hypothesis that sex hormones may influence colorectal cancer risk was formulated in the early 1980s, but epidemiological studies on a relationship between colorectal cancer risk and hormone replacement therapy (HRT) have only accumulated over the last few years. To investigate the relationship between HRT and colon and rectal cancer and the role of other covariates that might modify it, we analyzed combined data from two case-control studies conducted in Italy between 1985 and 1996, including 994 women with incident colon cancer, 542 with rectal cancer, and 3110 controls with acute, non-neoplastic, nondigestive, non-hormone-related disorders. Odds ratios (ORs) and 95% confidence intervals (CIs) were derived from unconditional multiple logistic regression equations including terms for age, center/study period, education, family history of colorectal cancer, status and age at menopause, parity, use of oral contraceptives, total energy intake, and body mass index. Ever use of HRT was inversely associated with cancer of the colon (OR = 0.64, 95% CI = 0.46-0.88) and of the rectum (OR = 0.46, 95% CI = 0.29-0.72). Increasing duration of use of HRT was related to decreasing risk for colon and rectal cancers (P for trend < 0.01). No interaction emerged, and the inverse association persisted across separate strata of other risk factors. This study, one of the largest case-control investigations on exogenous female hormones and colorectal cancer thus far, provides further evidence that women who have ever used HRT are at lower risk of colon and rectal cancer. Because colorectal cancer is the second most common neoplasm and cause of death among nonsmoking women in developed countries, these results may have a major public health impact.

Aged↗
PubMed1998

Oral contraceptive use and risk of colorectal cancer.

To evaluate the relation between oral contraceptives and colon and rectal cancer, we analyzed combined data from two case-control studies conducted in six Italian regions between 1985 and 1996. The studies included 803 women with incident colon cancer, 429 with rectal cancer, and 2,793 controls with acute, nonneoplastic, nondigestive, non-hormone-related disorders. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) from unconditional multiple logistic regression equations, including terms for age, center/study period, education, family history of colorectal cancer, menopausal status, age at menopause, parity, use of hormone replacement therapy, body mass index [weight (kg) per height squared (m2)], and total energy intake. Ever-use of oral contraceptives was inversely associated with colon cancer (OR = 0.63; 95% CI = 0.45-0.87) and rectal cancer (OR = 0.66; 95% CI = 0.43-1.01). Duration of use of oral contraceptives was inversely related to risk of colon but not rectal cancer. This study suggests that women who have ever used oral contraceptives are at lower risk of colon and rectal cancer.

Adult↗
PubMed1997

Intake of selected micronutrients and risk of colorectal cancer.

The relationship between various micronutrients and colorectal cancer risk was investigated using data from a case-control study conducted between January 1992 and June 1996 in Italy. Cases were 1,953 incident, histologically confirmed colorectal cancers (1,225 of the colon and 728 of the rectum), admitted to the major teaching and general hospitals in the study areas, and 4,154 controls with no history of cancer, admitted to hospitals in the same catchment areas for acute, non-neoplastic diseases unrelated to the digestive tract and requiring no long-term modifications of the diet. Dietary habits were investigated using a validated food-frequency questionnaire. Odds ratio (ORs) were computed after allowance for age, sex and other potential confounding factors, including physical activity, total energy and fibre intake. For most micronutrients, ORs were below unity with increasing quintile of intake. The most consistent protective effects were for carotene, riboflavin and vitamin C (Multivariate ORs from the continuous model, with unit set as the difference between the upper cut-point of the 4th quintile and that of the 1st one, were 0.65, 0.73 and 0.80, respectively). Inverse relationships were observed also for calcium and vitamin D (ORs of 0.85 and 0.93, respectively). When the combined effect of calcium and vitamin D and selected anti-oxidants was considered, the OR reached 0.46 in subjects reporting high calcium/vitamin D and high anti-oxidant intake compared to those reporting low intake of both groups of micronutrients. Most results were apparently stronger for colon cancer and among females. Our results provide further support for a protective effect of several micronutrients on colorectal cancer risk and some indications for a specific and stronger effect of selected anti-oxidants.

Adult↗
PubMed1997

Epidemiology of bladder cancer in Alexandria, Egypt: tobacco smoking.

The relationship between smoking and bladder cancer risk was investigated using data from a case-control study conducted between January 1994 and July 1996 in Alexandria, Egypt. Cases were 151 males with incident, histologically confirmed invasive cancer of the bladder, and controls were 157 males admitted to hospital for acute, non-neoplastic, non-urinary tract, non-smoking-related conditions. With reference to never smokers, ex-smokers had a multivariate odds ratio (OR) of 4.4 [95% confidence interval (CI) 1.7-11.7] and current smokers of 6.6 (95% CI 3.1-13.9). The ORs were 5.4 for < 20 and 7.6 for > or = 20 cigarettes per day. After adjustment for cigarette smoking, the ORs were 0.8 for waterpipe and 0.4 for hashish smokers. The risk was significantly related to duration of smoking (OR of 16.5 for > 40 years), and inversely related to age at starting (OR of 8.8 for starting < 20 years), and inversely related to time since quitting smoking. Compared with never smokers who did not report a clinical history of schistosomiasis, the OR was 9.4 for smokers with a history of schistosomiasis, and 10.7 for smokers ever employed in high-risk occupations compared with non-smokers not reporting such a history. Thus, our results, while not giving indications of an increased bladder cancer risk with habits other than cigarette smoking, found a remarkably strong association with various measures of cigarette smoking that could explain 75% of bladder cancer cases among males from Alexandria. The prevalence of smoking was very low among women, and consequently tobacco was not a relevant risk factor for female bladder cancer.

Adult↗
PubMed1997

Family history of cancer and risk of breast cancer.

The relationship between breast cancer risk and family history of cancer in first-degree relatives was investigated using data from a multicentric case-control study conducted in Italy between June 1991 and April 1994 on 2,569 women aged less than 75 years, with histologically confirmed incident breast cancer, and 2,588 control women admitted to hospital for acute, non-neoplastic, non-gynaecological conditions. Relative to women with no history, those with a family history of breast cancer had an odds ratio (OR) of 2.4 [95% confidence interval (CI) 1.9-3.0], and those with family history of intestinal cancer had an OR of 1.3 (95% CI 1.0-1.7). No significant relations emerged between breast cancer risk and family history of prostate (OR 1.1), ovarian (OR 1.3), cervical or endometrial (OR 1.2) or other cancers, except gallbladder (OR 8.6). The OR for family history of any type of cancer except breast cancer was 1.1. For family history of breast cancer the ORs were similar across strata of age of the proband, being 2.4 below age 45, 2.2 at age 45-59 and 2.7 above age 60, and whether the relative affected was the mother, sister(s) or both, while the risk appeared higher if the age at onset of breast cancer in the relative was lower than 40 years (OR 3.5), rather than higher (OR 2.2). Thus, our results, based on the investigation of all neoplasms in first-degree relatives, confirm that breast cancer risk is increased in women with a family history of breast cancer, while there was no material association with family history of cancer in general, excluding breast cancer.

Adult↗
PubMed1997

Diet diversity and gastric cancer.

It has long been suggested that a varied diet may protect against gastric cancer, in the absence, however, of definition and quantification of the issue. Thus, we considered the relationship between diet diversity (i.e., variety of food intake computed as the total number of foods consumed at least once per week) and the risk of gastric cancer using data of a case-control study conducted between 1985 and 1993 in northern Italy on 746 gastric-cancer cases below age 75 years and 2,053 controls admitted to hospital for acute, non-neoplastic, non-digestive-tract diseases. A significant inverse association was observed between various measures of food diversity and gastric cancer risk. Compared with subjects in the lowest quartile of total diversity, the multivariate odds ratios (ORs) were 0.9 for the second, 0.9 for the third and 0.7 for the highest quartiles. The inverse association was even stronger for vegetable (OR = 0.5 for the highest level) and fruit (OR = 0.6) diversity. Our findings were not explained by allowance for total calorie intake and total number of servings, besides education as an indicator of social class, and support, therefore, the concept that a more diversified and richer diet is a relevant underlying correlate of the decline in gastric cancer rates.

Adult↗
PubMed1997

Attributable risks for breast cancer in Italy: education, family history and reproductive and hormonal factors.

The percent population attributable risk (AR) for breast cancer was estimated in relation to education, family history of the disease and some reproductive and hormonal factors, using data from a case-control study conducted between June 1991 and February 1994 in 6 Italian centres on 2,569 histologically confirmed incident breast cancer cases and 2,588 controls, admitted to hospital for a wide range of acute, non-neoplastic, non-hormone-related diseases. On the basis of multivariate odds ratios, a high level of education accounted for 20% of cases, elevated age at first birth and nulliparity for 38% and a family history of breast cancer in first-degree relatives for 7%. Education and nulliparity and age at first birth together explained 47% of all breast cancer cases, and the combination of these 2 factors plus a family history of the disease explained 50% of cases. In pre-menopausal women a high level of education accounted for 31% of all breast cancer cases, older age at first birth for 44% and the combination of the 2 factors for 49%. In post-menopausal women the corresponding values were 13%, 31% and 42%; further addition of risk associated with family history of the disease explained 52% of pre-menopausal cases. In post-menopausal women older age at menopause and the use of hormone replacement therapy accounted for 15% and 2% of breast cancer cases, respectively. The combination of risks associated with a high level of education, old age at first birth and nulliparity and older age at menopause accounted for 51% of cases; further inclusion of risk associated with use of hormone replacement therapy explained 52%, and the AR resulting from these 4 risk factors combined plus a family history of breast cancer was 56%. Thus, a few selected and well-identified risk factors explain about one-half the breast cancer cases in this Italian population.

Age Factors↗
PubMed1997

Hysterectomy, oophorectomy in premenopause, and risk of breast cancer.

OBJECTIVE: To analyze the risk of breast cancer in women who underwent pelvic surgery in premenopause using data from two case-control studies conducted between 1983 and 1994 in six Italian centers. METHODS: Subjects were 5984 women with histologically confirmed breast cancer diagnosed within the year before interview who were admitted to the major teaching and general hospitals in the areas included in the studies. Controls were 5504 women who resided in the same geographic areas and were admitted for acute conditions to the same network of hospitals in which cases had been identified. Women were not included if they had been admitted for gynecologic, hormonal, or neoplastic disease. RESULTS: A total of 719 cases (12%) and 801 controls (15%) underwent pelvic surgery before menopause. The risk of breast cancer was reduced in women who underwent bilateral oophorectomy with hysterectomy (odds ratio [OR] adjusted for age, calendar year at interview, study, and center, 0.8, 95% confidence interval [CI] 0.7, 0.9) and hysterectomy alone (OR 0.7, 95% CI 0.6, 0.8). The protection tended to increase with time since surgery, but no relationship emerged when age at menopause was included in the analysis. No clear relationship emerged between time since unilateral oophorectomy with or without hysterectomy or since hysterectomy alone and breast cancer risk. CONCLUSION: The risk of breast cancer is lower in women who undergo bilateral oophorectomy before menopause, and the protection increases with time from surgery.

Adult↗
PubMed1997

Attributable risks for hepatocellular carcinoma in northern Italy.

The population attributable risks (ARs) for hepatocellular carcinoma (HCC) were estimated in relation to low education level, heavy alcohol consumption, low vegetable and fruit intake, history of hepatitis, diabetes, liver cirrhosis and oral contraceptive use, using data from a case-control study conducted between 1984 and 1993 in Northern Italy. Cases were 320 patients (235 males and 85 females) with histologically or serologically confirmed HCC, and controls were 1408 patients (1031 males and 377 females) admitted to the same network of hospitals for acute, non-neoplastic or non-digestive tract conditions, unrelated to any of the known or likely risk factors for primary liver cancer. The ARs were 40% for low vegetable and fruit consumption, 31% for low education, 18% for liver cirrhosis, 16% for hepatitis, 8% for diabetes and 7% for heavy alcohol consumption. Together, these factors explained 74% of hepatocellular cancer cases. Compared with females, males had higher ARs for cirrhosis (21% versus 11%), diabetes (10% versus 2%) and heavy alcohol consumption (9% versus 1%). The percentage of HCC attributable to all factors considered together was 78% for males and 67% for females. Thus, even if available information on hepatitis and dietary factors was limited, and the AR estimates were based on several arbitrary assumptions, available knowledge could, in principle, reduce the burden of the disease in Italy from 3300 deaths to approximately 750 for males, and from 1600 to approximately 500 for females.

Adult↗
PubMed1997

Quitting smoking in northern Italy: a cross-sectional analysis of 2621 subjects.

To describe the relationship between sociodemographic factors, life-style habits, selected dietary indicators, smoking-related variables, and quitting smoking we analyzed data derived from the comparison group of a case-control study of colorectal and breast cancers based on a network of teaching and general hospitals in Northern Italy. A total of 2621 subjects (1215 women and 1406 men) who were ever cigarette smokers were included for analysis. Age-adjusted rates of stopping smoking (quit rates) and multivariate odds ratios (OR) of quitting smoking were computed. The overall age-adjusted quit rate was 38.6% for males and 24.9% for females, corresponding to an OR of quitting of 0.6 (95% CI: 0.5-0.7) for females vs males. The quitting rate increased with increasing age. After allowing for age, smoking cessation was more frequently reported by more educated or higher social class individuals. No relationship was present between quitting smoking and alcohol consumption, but quitting smoking was inversely related to coffee consumption. The probability of quitting smoking increased directly with number of cigarettes among males but not among females, who showed a J-shaped pattern. Older, heavy smokers were more likely to give up smoking. A general pattern of increasing rates of quitting smoking with higher consumption of vegetables and fruit, and hence beta-carotene, was present. This study confirms a positive association between quitting smoking and increasing age, higher education, low coffee consumption, heaviness of smoking and high consumption of vegetables and fruit.

Adult↗
PubMed1997

Nutrient intake according to education, smoking, and alcohol in Italian women.

The control group of a hospital-based case-control study on breast cancer was used to assess the relationships between education, smoking habits, alcohol consumption, and intake of selected macro- and micronutrients in Italian women. The study subjects were 2,588 women admitted to a network of hospitals in various Italian regions for nonneoplastic, acute diseases unrelated to long-term changes in the diet. Although relatively few differences were observed, less educated subjects consumed more linoleic acid and polyunsaturated fats than did more educated women. Smoking habits were associated with the largest differences in selected antioxidant vitamins. Significant differences were observed for beta-carotene and vitamin C intake, with an 11% higher intake of beta-carotene and a 12% higher intake of vitamin C in ex-smokers than in current smokers. Heavier alcohol drinkers tended to consume more retinol and iron but less beta-carotene than did moderate or nondrinkers. Thus the differences in macro- and micronutrient intake were generally moderate across categories of education, smoking, and alcohol consumption in this data set of Italian women. Nonetheless, they confirm the importance of allowing for these variables in analyzing the relationship between nutritional factors and disease risk.

Adult↗
PubMed1997

Intake of selected foods and nutrients and breast cancer risk: an age- and menopause-specific analysis.

The relationship between selected foods and nutrients and breast cancer risk was investigated in strata of age and menopausal status using data from a case-control study on breast cancer conducted between June 1991 and April 1994 in six Italian areas. Cases were 2,569 women with histologically confirmed incident breast cancer admitted to the major teaching and general hospitals of the study areas; controls were 2,588 women with no history of cancer admitted to hospitals in the same catchment area as cases for acute, nonneoplastic, nongynecological conditions unrelated to hormonal or digestive tract diseases or to long-term modifications of diet. Dietary habits were investigated using a validated food frequency questionnaire, including 78 foods or food groups. Among food groups, bread was directly and significantly related to breast cancer risk in older women and, consequently, in postmenopause, whereas the protection conferred by fish consumption was stronger in postmenopause and that exerted by raw vegetables was stronger in premenopause. Among nutrients, unsaturated fatty acids were inversely related to breast cancer risk, the association being stronger in postmenopausal and elderly women. The pattern was similar for total fats. For starch, available carbohydrates, and total proteins, no heterogeneity emerged across strata of age and menopausal status. Among micronutrients, protection diminished with increasing age for beta-carotene and calcium, whereas no heterogeneity emerged for vitamin E. Thus this age-specific analysis of the largest investigation to date on diet and breast cancer did not show any consistent pattern of breast cancer risk in relation to selected dietary factors across strata of age and menopausal status.

Adult↗
PubMed1997

Risk of stomach cancer in patients with gastric or duodenal ulcer.

It has been suggested that the risk of stomach cancer is increased when there is a history of gastric ulcer, but decreased in those with a history of duodenal ulcer. To provide further information on the issue, data from a case-control study of gastric cancer conducted in greater Milan, northern Italy, between 1985 and 1993, were examined. There were 746 cases of gastric cancer below the age of 75 and 2,053 controls admitted to hospital for acute, non-neoplastic, non-hormone-related diseases. A total of 76 (10.2%) cases and 84 (4.1%) controls reported a history of gastric ulcer, corresponding to a multivariate odds ratio (OR) of 2.6 (95% confidence interval, CI = 1.8-3.6). Fifty nine cases (7.9%) and 111 (5.4%) controls reported a history of duodenal ulcer, corresponding to an OR of 1.3 (95% CI = 0.9-1.8). The OR of gastric cancer was significantly above unity for the first five years after diagnosis of gastric ulcer (OR = 7.4, 95% CI 3.7-14.8), and declined thereafter. No consistent pattern of risks was observed after duodenal ulcer. The present data therefore confirm that the risk of gastric cancer is increased after gastric ulcer. They do not support, however, a reduced risk after duodenal ulcer. This may be due to variable baseline characteristics of the populations studied, or to the different role and impact of Helicobacter pylori and other determinants of duodenal ulcer and gastric cancer in various countries.

Age Distribution↗
PubMed1997

Hormone replacement treatment and breast cancer risk: an age-specific analysis.

The relationship between hormone replacement treatment (HRT) and breast cancer risk was considered in age-specific groups of women, combining data from two case-control studies conducted between 1983 and 1994 in six Italian centers. Cases were comprised of 5984 women, below age 75 years, with histologically confirmed breast cancer, and controls were comprised of 5504 women admitted to the hospital for a wide spectrum of acute, nonneoplastic, nonhormone-related diseases. Ever-use of HRT was reported by 6.1% of the cases and 5.5% of the controls, corresponding to a multivariate odds ratio (OR) of 1.2 [95% confidence interval (CI), 1.0-1.4]. A significant trend in risk with duration of use was observed. Separate analysis for women < 55, 55-64, and 65-74 years old at diagnosis showed that the excess risk of breast cancer associated with ever-use of HRT was not observed in the youngest age group (OR, 0.9) and increased with age at diagnosis to 1.2 (95% CI, 0.9-1.5) for women 55-64 years old and 1.6 (95% CI, 1.2-2.3) for those 65-74 years old at diagnosis. A significant trend in risk with duration was observed only in the oldest group (65-74 years old), with ORs of 1.6 (95% CI, 1.1-2.3) and 2.2 (95% CI, 1.1-4.7), respectively, for < 60 and > or = 60 months of use. Thus, this study suggests that the relationship between HRT and breast cancer risk is influenced by age at diagnosis and that any risk-benefit assessment is particularly critical for women using HRT several years after menopause.

Adult↗
PubMed1996

Lactation and the risk of breast cancer in an Italian population.

The relation between breast feeding and breast cancer was investigated in a multicentric case-control study conducted in Italy on 2,167 parous women with histologically confirmed breast cancer, diagnosed within 1 year, and 2,208 parous control women admitted to hospitals in the same catchment areas of cases for acute, non-neoplastic, non-gynecological non-hormone-related diseases. Compared with women who had never tried to lactate, those who had always failed had a multivariate odds ratio (OR; adjusted for parity, education and several other potential confounding factors) of 0.94, and those who had lactated had an OR of 1.17. The multivariate ORs of women who had breast fed 1, 2 and 3 or more children were, respectively, 1.14, 1.18 and 1.32, compared with women who had never lactated. None of these ORs was statistically significant. Compared with women who had never breast fed, the multivariate ORs were 1.19 for women reporting less than 6 months of breast feeding, 1.15 for 6-11 months, 1.34 for 12-17 months, 1.10 for 18-23 months and 0.86 for 24 months or more. No appreciable difference was evident across strata of age, menopausal status, parity and age at first birth, while there was a hint of interaction with education. Our study therefore excluded any appreciable protective role for lactation in breast cancer risk, with the patterns of lactation in this European population, aside from the protective role of parity on breast carcinogenesis.

Adult↗