The association between low-dose aspirin use and the incidence of colorectal cancer: a nationwide cohort study.

BACKGROUND: Considerable evidence suggests that aspirin has a chemopreventive effect on colorectal cancer (CRC). However, optimal dose and treatment duration have not been defined, and data on the effects of low-dose aspirin are contradictory. AIM: To determine if the incidence of CRC in patients with low-dose aspirin use was lower than in those without aspirin use. METHOD: From Taiwan's National Health Insurance research database, aspirin users (n = 1985) were defined as adults (age ≥20 years) with at least 3.5 years of regular low-dose aspirin use (50-150 mg per day) between 1998 and 2002. Non-users (n = 7940) were those who did not use aspirin and were matched 4:1 with the user group by age, gender, date of ambulatory care (index date), and presence of known risk factors for cardiovascular disease (including hypertension, diabetes mellitus and hyperlipidaemia). Follow-up of the two study groups was made until the end of 2010, and incidences and hazard ratios of colorectal cancer were determined. RESULTS: During a median follow-up period of 8.9 years, 129 non-users and 14 users developed CRC, corresponding to incidence rates of 180.43 and 79.42 per 100,000 person-years respectively. Duration of aspirin use among users ranged from 3.5 to 12.6 years (mean 8.7 years). The multivariate-adjusted hazard ratio for CRC was 0.5 (95% confidence interval 0.28-0.87) among users as compared with non-users. CONCLUSIONS: Long-term use of low-dose aspirin appears to be associated with a lower incidence of CRC in patients with high cardiovascular risk. Further randomised clinical trials are necessary to confirm these findings.

Cancer risk among patients with systemic sclerosis: a nationwide population study in Taiwan.

OBJECTIVES: Systemic sclerosis (SSc) has been associated with high cancer risk. We compared the cancer risk among SSc patients with that among the general Taiwanese population. METHODS: The catastrophic illness registry of the Taiwan National Health Insurance Research Dataset (NHIRD) was used to identify patients diagnosed with SSc and cancer in Taiwan during 1996-2008. The standardized incidence ratio (SIR) for cancer was calculated, and mortality was ascertained using the data from the National Death Registry. RESULTS: Data analysis revealed that 2053 (472 men, 1581 women) Taiwanese individuals were diagnosed with SSc during the study period and 83 (30 men, 53 women) had cancer. The incidence of cancer was 6.9/1000 person-years. The most common cancer sites in male SSc patients were the lung (n = 10), oral cavity and pharynx (n = 8), and gastrointestinal tract (n = 4), and those in female patients were the breast (n = 11), lungs (n = 11), and blood (n = 6). Compared to the Taiwanese population of 1996, the all-cancer SIR for SSc was 1.63 [95% confidence interval (CI) 1.31-2.01]. Cancer risk was elevated for cancers of the lung (SIR 4.20), oral cavity and pharynx (SIR 3.67), and blood (SIR 3.50). A cancer diagnosis in SSc patients was associated with a hazard ratio (HR) of 2.15 (95% CI 1.30-3.53). Among cancer patients, a diagnosis of SSc was not associated with increased mortality. CONCLUSIONS: SSc patients are at high risk of developing cancer, especially of the lung, oral cavity and pharynx, and blood.

Incidence, cancer risk and mortality of dermatomyositis and polymyositis in Taiwan: a nationwide population study.

BACKGROUND: Nationwide data on the epidemiology of dermatomyositis (DM) and polymyositis (PM) were limited. OBJECTIVES: This study was to estimate the incidence, occurrence of cancer and mortality of DM and PM in Taiwan. METHODS: Both the register of critical illness of the Taiwan National Health Insurance Research Dataset and the National Death Registry of Taiwan were used to calculate estimates of the incidence, cancer association, and mortality of DM and PM between 2003 and 2007. RESULTS: A total of 803 DM and 500 PM cases were identified between 2003 and 2007. Mean age at diagnosis was 44·0 ± 18·3 years for DM and 49·2 ± 15·9 years for PM. The overall annual incidences of DM and PM were 7·1 (95% CI 6·6-7·6) and 4·4 (95% CI 4·0-4·8) cases per million population. The incidence of both DM and PM increased with age and reached a peak at age 50-59 years. One hundred and eleven (13·8%) patients with DM and 31 (6·2%) patients with PM had cancers. The diagnosis of most cancers was made after the diagnoses of DM (n = 71; 64·0%) and PM (n = 21; 67·7%). Overall, the standardized incidence ratios (SIR) for cancer were 5·36 (4·12-6·87) and 1·80 (1·10-2·79) among patients with DM and PM; however, during the first year, SIRs for cancer were 24·55 (95% CI 18·62-31·79) and 9·17 (95% CI 14·82-15·93) in patients with DM and PM, respectively. The most common types of cancer were nasopharyngeal cancer for men and breast cancer for women. Patients with DM and PM had standardized mortality ratios of 7·68 (6·41-9·01) and 5·29 (4·28-6·48). CONCLUSION: This study reports robust estimates of important aspects of the epidemiology of both DM and PM in Taiwan. This highlights the rarity of these diseases, and their associated cancer risks and increased mortality.

A procedure for purifying jack bean urease for clinical use.

Urease with a purity meeting the requirements of analytical use was purified from jack bean meal through steps consisting of 20% acetone extraction, heat treatment, acid precipitation, and lyophilization. For extraction of urease, one part of bean meal was mixed with 5 parts of 20% acetone containing 1 mM EDTA and 1 mM 2-mercaptoethanol, and stirred at 20 degrees C for 5 min. Milky substances in the extract were removed by heat treatment. Urease in the clear yellow supernatant was precipitated by adjusting the pH of the solution to 5.4 with citric acid. The acid precipitated urease was neutralized by dissolving in 0.015 M phosphate buffer, pH 8.5 (final pH 6.8 to 7.0) and then lyophilized. By this procedure, the purity of the enzyme was increase 14.7 fold, the recovery of activity was 63%, and the yield was 6.75 g from 1 kg of bean seeds. The specific activity of the preparation was 411 units/mg protein (240 units/mg solid), and the free ammonia content was less than 0.01 microgram per unit. Some other proteins were present in the urease preparation as examined by gel filtration and gradient polyacrylamide gel electrophoresis. The molecular weight of the enzyme estimated by gel filtration was 480,000. However, two urease activity bands with molecular weight of 230,000 and 480,000 were observed in the polyacrylamide gel electrophoregram. From the result of determination of blood urea nitrogen (BUN), this simple purification procedure could be used for practical preparation of urease from jack bean meal for clinical analysis.