Citations

AbstractCalcium channel blockers block calcium signal-mediated apoptosis. It is hypothesized that the use of these drugs may be associated with the development of cancer. This study investigated the association between daily use of calcium channel blockers and prostate cancer in a community-based cohort of men who participated in a longitudinal study of lower urinary tract symptoms. Study subjects were men ages 40 to 79 years by January 1, 1990, and were randomly selected from Olmsted County in Minnesota. At baseline, participants underwent an interview to determine all medications taken on a daily basis, including calcium channel blockers and to elicit a family history of prostate cancer. During follow-up, all men with a histological diagnosis of prostate cancer were identified through patient self-report and by a review of the complete medical record. Over 12,668 person years of follow-up, 15 (6.8%) of 220 calcium channel blocker users and 120 (10.5%) of 1142 nonusers developed prostate cancer (P = 0.09; odds ratio, 0.62; 95% confidence interval, 0.36–1.10). With adjustment for age and family history of prostate cancer, the risk (odds ratio, 95% confidence interval) of prostate cancer was 0.55 (0.31–0.97) in calcium channel blocker users compared with nonusers. In analyses stratified by family history of prostate cancer, the risk of prostate cancer was 0.45 (0.23–0.88) in men without a family history and 2.64 (0.82–8.47) in men with a family history of prostate cancer (P = 0.006). These findings suggest an association between prostate cancer and daily use of calcium channel blockers that varies by family history of prostate cancer.

SummaryImmunity to measles is conferred by the interplay of humoral and cellular immune responses, the latter being critical in maintaining long-term recall response. Therefore, it is important to evaluate measles-specific humoral and cellular immunity in populations several years after vaccination and understand the correlations among these measures of immunity. We examined measles-specific antibodies, lymphoproliferation and the Th1/Th2 signature cytokines, interferon (IFN)-γ and interleukin (IL)-4, in a population-based cohort of healthy children from Olmsted County, Minnesota after two doses of measles–mumps–rubella-II (MMR-II) vaccine. We detected positive measures of measles-specific cellular and humoral immunity in the majority of our study population. However, a small proportion of subjects demonstrated an immune response skewed towards the Th2 type, characterized by the presence of either IL-4 and/or measles-specific antibodies and a lack of IFN-γ production. Further, we observed a significant positive correlation between lymphoproliferation and secretion of IFN-γ (r = 0·20, P = 0·0002) and IL-4 (r = 0·15, P = 0·005). Measles antibody levels were correlated with lymphoproliferation (r = 0·12, P = 0·03), but lacked correlation to either cytokine type. In conclusion, we demonstrated the presence of both long-term cellular and humoral responses after MMR-II vaccination in a significant proportion of study subjects. Further, a positive correlation between lymphoproliferation and IL-4 and IFN-γ suggests that immunity to measles may be maintained by both Th1 and Th2 cells. We speculate that the Th2 biased response observed in a subset of our subjects may be insufficient to provide long-term immunity against measles. Further examination of the determinants of Th1 versus Th2 skewing of the immune response and long-term follow-up is needed.

SummarySmith–Lemli–Opitz syndrome is a rare autosomal recessive disorder characterized by multiple congenital anomalies and various degrees of cognitive deficits. This condition results from a deficiency of 7‐dehydrocholesterol reductase, a critical step in cholesterol biosynthesis. Children with Smith–Lemli–Opitz syndrome have frequent infections, particularly of the respiratory tract. Immunodeficiency, however, is not recognized as a part of this metabolic condition. Frequent infections are usually attributed to a decreased patient mobility and reduced respiratory effort secondary to muscular hypotonia and mental retardation, which are often present in affected individuals. We describe a patient with Smith–Lemli–Opitz syndrome and recurrent respiratory infections who was found to have a selective antibody deficiency. The immunological diagnosis was based on an absent immune response to Pneumovax. She also had no immunological response to hepatitis B vaccine and was unable to break down red cells with isoagglutinin B. Therapy with intravenous IgG (IVIG) was initiated. Infections were less severe, although they still occurred in a high frequency after initiation of the IVIG therapy. This finding prompts the need for a higher index of suspicion for an underlying immune deficiency in patients with Smith–Lemli–Opitz syndrome who present with recurrent and chronic infections. Early recognition and appropriate therapeutic interventions may decrease the severity of infections, prevent potentially fatal infections, and eventually improve the quality of life in these patients.