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Biomedical subjects

P Boyle

Publications and source records attributed to P Boyle.

At least 253 records · Page 14Linked to original sources
PubMed1993

The time trend and age-period-cohort effects on incidence of adenocarcinoma of the stomach in Connecticut from 1955-1989.

BACKGROUND: Adenocarcinoma of the gastric cardia has been be increasing in Connecticut, and the risk factors responsible for the increasing incidence are unknown. This study examined the incidence pattern of adenocarcinoma of the gastric cardia and distal stomach in Connecticut during the past decades and identified components of birth cohort, period, and age as determinants of the observed time trends by regression modeling. METHODS: This study was based on all histologically confirmed incident cases of gastric adenocarcinoma reported to the Connecticut Tumor Registry between 1955 and 1989. Stomach cancers were grouped into cancers of the gastric cardia, distal stomach, or unknown/unspecified subsite. Age-adjusted incidence rates were calculated by the direct method standardized to the 1970 United States population. A regression model was used to identify birth cohort, period, and age as determinants of the observed time trends. RESULTS: The results indicated that the incidence rate of adenocarcinoma of the cardia is increasing, particularly in white males, whereas adenocarcinoma of the distal stomach is now decreasing in both sexes in Connecticut. Regression modeling suggests that the increase of adenocarcinoma of the cardia may be explained partly by a birth cohort phenomenon. CONCLUSION: There is little information regarding the risk factors that might be responsible for the observed increasing trend for adenocarcinoma of the cardia, although smoking, alcohol intake, retinol intake, and hiatal hernia have been associated with an increased risk of adenocarcinoma of the cardia or gastric cancer. Considering the different epidemiologic features of adenocarcinoma of the cardia and distal stomach, future analytic studies should separate cancer of the gastric cardia and cancer of the distal stomach in searching for etiologic factors.

Adenocarcinoma↗
PubMed1993

Cigarette smoking, alcohol, tea and coffee consumption and pancreas cancer risk: a case-control study from Opole, Poland.

A population-based, case-control study of pancreas cancer was undertaken in Opole, Poland, within the framework of the SEARCH Programme of the International Agency for Research on Cancer: this is the first aetiological study of pancreas cancer reported from Poland where the reported mortality rate has doubled since 1963. This study of pancreas cancer has provided some further supporting evidence of an association between increased pancreas risk with increasing levels of cigarette smoking. The risk rose with increasing lifetime cigarette consumption with a trend which was weakly significant (p = 0.061). Findings regarding lifetime tea and coffee consumption were not consistent with intake of either beverage increasing the risk of this disease. There was a strongly significant trend of decreasing risk with increasing lifetime consumption of tea (p < 0.001), which was also apparent when the analysis was restricted to subjects who were interviewed directly. For coffee consumption, which is low in Poland, there was also a negative association apparent in the data which was not statistically significant among the sub-set of subjects who were directly interviewed. The findings regarding alcoholic beverages were overall null, although the weakly positive trend in risk with spirits consumption (p = 0.71) may deserve further investigation in view of the special nature of the source of spirits (vodka) in Poland.

Adult↗
PubMed1993

A novel monoclonal human IgM autoantibody which binds recombinant human and mouse tumor necrosis factor-alpha.

Several monoclonal human IgM antibodies to recombinant human tumor necrosis factor-alpha (rhTNF alpha) have been generated and partially characterized. The F78-1A10-B5 monoclonal antibody (mAb) (B5) binds to rhTNF alpha with a titer comparable to three high-affinity neutralizing mouse mAbs, when tested by ELISA. However, the B5 mAb binds relatively weakly to soluble rhTNF alpha. It appears to bind to epitopes on rhTNF alpha distinct from those bound by the mouse mAbs for three reasons. First, preincubation of plate-bound rhTNF alpha with mouse mAbs does not decrease or compete subsequent B5 mAb binding. Second, rhTNF alpha complexed to the mouse mAbs can still be bound by B5 mAb. Third, the mouse mAbs neutralize TNF alpha cytotoxicity whereas the B5 mAb does not. Binding analyses indicate that this human IgM autoantibody binds to both human and mouse recombinant TNF alpha, but not to other antigens commonly recognized by polyreactive natural IgM autoantibodies. The high level of amino acid identity between the human and mouse TNF alpha molecules suggest that the B5 mAb is monospecific for a given epitope shared by these two forms of TNF alpha. This spectrum of characteristics makes B5 a novel mAb.

Animals↗
PubMed1993

The B5 monoclonal human autoantibody binds to cell surface TNF alpha on human lymphoid cells and cell lines and appears to recognize a novel epitope.

A human IgM monoclonal antibody (B5) recognizing human TNF alpha was established from peripheral blood lymphocytes by transformation with Epstein-Barr virus and subsequent cell fusion. The B5 monoclonal antibody (mAb) binds to cell surface TNF alpha (csTNF alpha) on human T cells, B cells, and monocytes. In addition, this autoantibody binds to csTNF alpha on a variety of lymphoid and monocyte lineage cell lines of human origin, as well as astrocytomas, a breast carcinoma, and a melanoma. Interestingly, the B5 mAb also binds to chimpanzee lymphocytes and to mouse T lymphoma cell line csTNF alpha. Many neutralizing mouse anti-TNF alpha mAbs do not exhibit comparable binding to csTNF alpha. This is consistent with the previous demonstration that B5 recognizes an epitope on TNF alpha distinct from those recognized by three neutralizing mouse anti-TNF alpha mAbs. B5 binding to csTNF alpha is specific since it can be inhibited by TNF alpha. No inhibition of B5 binding was seen by a neutralizing mouse anti-TNF alpha mAb. The B5 autoantibody appears to recognize the transmembrane form of TNF alpha and most likely also recognizes TNF alpha associated with its receptor. The unique specificity of this B5 autoantibody provides some additional insight into the complex physiology of cell surface-associated TNF alpha.

Animals↗
PubMed1993

Alcoholic beverage consumption and risk of breast cancer in Spain.

The relation between alcoholic beverage consumption and risk of breast cancer was examined. We used data from a population-based, case-control study that included almost all incident cases occurring in five Spanish regions from February 1990 to July 1991. A total of 762 women between 18 and 75 years of age, with a histologically confirmed, first diagnosis of breast cancer, were compared with 988 control women. Alcoholic beverage intake was measured by an interviewer-administered, semiquantitative food-frequency questionnaire. We used 'nondrinkers' as the reference category and divided the remainder into four categories according to alcohol intake. The multiple logistic analyses included not only alcohol intake but also possible confounding factors such as total caloric intake, age, socioeconomic status, and reproductive and medical histories. Even at moderate levels of alcohol intake (less than 8 g/day), a 50 percent increase in risk of breast cancer was found. The trend across categories of intake was statistically significant for wine and distilled drinks, as well as total alcohol intake. Consumption of 20 g or more of alcohol per day was associated with a 70 percent elevation in breast cancer risk compared with that of nondrinkers (adjusted relative risk (RR) = 1.7, 95 percent confidence interval = 1.3-2.3). Although the magnitude of the RR observed in our study was modest, our findings provide further support for a positive association between alcohol consumption and risk of breast cancer.

Adolescent↗
PubMed1993

The descriptive epidemiology of pharyngeal cancer in Scotland.

There have been recent reports of substantial increases occurring in the incidence of and/or mortality from tongue and mouth cancers in several countries. In this paper using data from Scotland (1960-89) we report on time trends in pharyngeal cancer. Similar increases in rates are evident for cancers of the oropharynx and hypopharynx while there has been little change in the occurrence of nasopharyngeal cancer (which has distinct aetiological factors). It therefore seems that reported changes in the incidence of and mortality from oral cancer may be real, and in Scotland, this is most probably due to changes in alcohol consumption.

Adult↗
PubMed1993

A case-control study of oral cancer in Beijing, People's Republic of China. Associations with nutrient intakes, foods and food groups.

A case-control study of oral cancer was conducted in Beijing, People's Republic of China to examine the association between dietary nutrient intake and risk of oral cancer, both in terms of estimated intake of nutrients and micro-nutrients, and in terms of specific foods and food groups. The study was hospital-based and controls were hospital in-patients matched for age and sex with the cases. The response rate for cases and controls was 100% and 404 case/control pairs were interviewed. The results suggest that increased protein and fat intake are related to a decreased risk of oral cancer. Carbohydrate intake, however, showed a moderate increased risk for oral cancer. Total carotene intake and carotene intake from fruits and vegetables are inversely associated with risk of oral cancer. A similar pattern was observed for dietary vitamin C intake. Dietary fibre derived from fruits and vegetables showed a strong negative association with oral cancer risk, but fibre derived from other sources did not exhibit any protective effect. At the level of foods and food groups, increased consumption of fresh meat, chicken and liver was significantly associated with a reduction in oral cancer risk: the tests for trend were all statistically significant at the P < 0.01 level. Consumption of common carp, hairtail, shrimp and lobster were also associated with decreased risk. Risk was found to increase with increasing consumption of millet and corn bread (P < 0.01) but to decrease with increasing consumption of rice (P < 0.01). Increased consumption of grapes, bananas, oranges, tangerines, peaches and pears were associated with reduced risk.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Chemoprevention of oral leukoplakia and chronic esophagitis in an area of high incidence of oral and esophageal cancer.

This intervention trial carried out in Uzbekistan (former USSR) in an area with a high incidence of oral and esophageal cancer involved random allocation of 532 men, 50 to 69 years old, with oral leukoplakia and/or chronic esophagitis to one of four arms in a double-blind, two-by-two factorial design, with active arms defined by the administration of (a) riboflavin; (b) a combination of retinol, beta-carotene, and vitamin E; or (c) both. Weekly doses were 100,000 IU of retinol, 80 mg of vitamin E, and 80 mg of riboflavin. The dose of beta-carotene was 40 mg/d. Men in the trial were followed for 20 months after randomization. The aim of the trial was to determine whether treatment with these vitamins or their combination could affect the prevalence of oral leukoplakia and/or protect against progression of oral leukoplakia and esophagitis, conditions considered to be precursors of cancer of the mouth and esophagus. A significant decrease in the prevalence odds ratio (OR) of oral leukoplakia was observed after 6 months of treatment in men receiving retinol, beta-carotene, and vitamin E (OR = 0.62; 95% confidence interval (CI): 0.39 to 0.98). After 20 months of treatment, no effect of vitamin supplementation was seen when the changes in chronic esophagitis were compared in the four different treatment groups, although the risk of progression of chronic esophagitis was lower in the subjects allocated to receive retinol, beta-carotene and vitamin E (OR = 0.65; 95% CI: 0.29 to 1.48) A secondary analysis not based on the randomized design revealed a decrease in the prevalence of oral leukoplakia in men with medium (OR = 0.45; 95% CI: 0.21 to 0.96) and high (OR = 0.59; 95% CI: 0.29 to 1.20) blood concentrations of beta-carotene after 20 months of treatment. Risk of progression of chronic esophagitis was also lower in men with a high blood concentration of beta-carotene, odds ratios being 0.30 (95% CI: 0.10 to 0.89) and 0.49 (95% CI: 0.15 to 1.58) for medium and high levels, respectively. A decrease in risk, also statistically not significant, was observed for high vitamin E levels (OR = 0.39; 95% CI: 0.14 to 1.10). These results were based on levels of vitamins in blood drawn after 20 months of treatment.

Aged↗
PubMed1993

The effect of differing radiotherapeutic schedules on the response of glottic carcinoma of the larynx.

Laryngeal tumours, especially T1N0M0 and T2N0M0 lesions, are readily controlled by radiotherapy. Studies have shown that control varies with the dose of radiotherapy delivered to the tumour. Other factors, including the dose per fraction and the time over which the treatment schedule is delivered are also important. The varying biological effectiveness of a number of different dose fraction time schedules used in the management of laryngeal tumours of different stages are considered, the end points being tumour control and associated morbidity. Special attention has been given to the length of time over which the schedule is delivered. Of the schedules examined the results would suggest that a dose of 60 Gy given in 25 fractions over a period of 35 days is the best of the six schedules studied for T1, T2, T3 and T4 lesions with minimal associated morbidity. It is possible, however, that the poor results shown on the Kaplan-Meier curves for patients treated with the schedule of 60 Gy in 30 fractions over a period of 42 days could be due to geographical misses of the tumours as 56% were treated without a beam directed shell. The poor result obtained when patients were treated with the schedule of 60 Gy given in 30 fractions over 49+ days may be due to tumour repopulation occurring during the rest period though the possibility of geographical misses may contribute to the poor tumour control results. Mathematical modelling using linear quadratic analysis suggests that the shorter the period of time over which the treatment is given the better chance of achieving tumour control irrespective of the stage of the disease. These models were developed for patients treated with a beam directed shell thus excluding those patients who are most likely to be at risk from a geographic miss of the tumour. Linear quadratic analysis of the treatment data suggests that the ratio alpha/beta for tumour cells is estimated in the region of 13 Gy. For T1 lesions the tumour doubling time is in the order of 6 days, with longer doubling times for the more advanced stages. The analysis provides some support for investigative use of accelerated treatment schedules. This analysis also shows the importance of using beam directed shells when treating small fields especially in the head and neck region.

Adult↗
PubMed1993

Development and validation of a food frequency questionnaire in Spain.

To create a suitable instrument to estimate intakes of total calories, protein, carbohydrate, fats (saturated, mono and polyunsaturated), alcohol, cholesterol, fibre, vitamin A and vitamin C in epidemiological studies conducted in Spain, a food frequency questionnaire was developed and tested. In particular, the questionnaire was designed to be used in a large population-based case-control study of dietary factors in relation to breast and colorectal cancer among women from different Spanish regions. After identifying the most important food sources of the relevant nutrients in the study population, the final version of the questionnaire asked about consumption of 118 food items. Its reproducibility and validity were tested among 147 Spanish women aged 18-74 years. These subjects were asked to complete the questionnaire before and after completing four 4-day food records. The records were obtained at 3-month intervals designed to represent daily and seasonal changes (between 1990 and 1991). Using the information available from standard Spanish food composition tables, an ad hoc computer program was created to translate food consumption into nutrient intake. The reproducibility of the questionnaire was assessed by means of estimating correlations between nutrient scores measured with the same instrument twice, with a period of 1 year between estimates. Pearson correlation coefficients ranged from 0.51 for saturated fat to 0.88 for alcohol. In the validity study, correlation coefficients between diet records and the first and second questionnaires ranged between r = 0.20 for vitamin A and r = 0.88 for alcohol.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗