Supplementation with a soluble β-glucan exported from Shiitake medicinal mushroom, Lentinus edodes (Berk.) singer mycelium: a crossover, placebo-controlled study in healthy elderly

Lentinus edodes (Shiitake) is a medicinal mushroom with a long tradition of use in Asia. The major active substance in L. edodes is a (1-6,1-3)-beta-glucan (lentinan). No clinical controlled studies have yet investigated the effect of orally administered lentinan on the immune response in healthy, elderly Caucasian subjects. We evaluated the effect and the safety of a beta-glucan from L. edodes mycelium, Lentinex, in healthy, elderly subjects in a double blind, crossover, placebo-controlled trial. Forty-two subjects were randomly allocated to two groups given orally either 2.5 mg/day Lentinex or placebo for 6 weeks; then after a washout period of 4 weeks, the alternate supplementation was given for 6 weeks. The changes in the number of B-cells were significantly different between the groups. The number ofNK cells increased significantly in both groups, but there was no significant difference between the groups. Other factors of the immune response (immunoglobulins, complement proteins, cytokines) were not altered. The safety blood variables (differential cell count, liver function, kidney function, and other blood chemistry) were not influenced by Lentinex, and the number, nature, and severity of adverse events were similar to placebo. Lentinex given orally to elderly subjects was safe and induced an increase in the number of circulating B-cells.     

Melphalan 100 mg/m2 with stem cell support as first relapse treatment is safe and effective for myeloma patients with long remission after autologous stem cell transplantation

Introduction: Today, a number of therapeutic options are available as the patient with myeloma relapses from initial treatment with high‐dose melphalan and autologous stem cell transplantation (ASCT). For patients who experience a durable response to primary ASCT, retreatment with high‐dose melphalan is recommended by many current guidelines. Yet, toxicity is an important aspect in the choice of relapse treatment, and a second ASCT in this setting could be associated with enhanced toxicity. As the goal for the treatment for relapsed myeloma should be disease control while maintaining quality of life, lower doses of melphalan might be preferable. Methods and Objectives: In this retrospective study, we account for the outcome of 66 patients with myeloma in first systemic relapse after ASCT, who were treated with intermediate‐dose melphalan, 100 mg/m², and stem cell support (MEL 100). The aim was to evaluate this treatment in relation to prior response duration after initial ASCT and with respect to response rate, toxicity and survival. Results: The overall response rate was 62%. There was limited, mostly haematological, toxicity, and no treatment–related mortality was observed. The median progression‐free survival (PFS) was 8.5 months, and the median overall survival was 24 months. Patients with time to progression of 34 months or more (n = 17; ≥75th percentile) after initial ASCT had a median PFS of 12.5 months after MEL 100. Conclusion: For patients with a long‐lasting response after ASCT, MEL 100 could be a therapeutic option with low toxicity and with efficacy comparable to newer immunomodulatory drugs.     

Case–control studies on risk factors for chronic obstructive pulmonary disease: how does the sampling of the cases and controls affect the results?

Introduction: Sampling is regarded as crucial to the validity of case–control studies. Ideally, cases and controls should be selected from the same source population, but deviations from this approach are often seen. Objective: Our objective was to examine how exposure–disease relationships in a study on chronic obstructive pulmonary disease (COPD) were affected by the sampling sources of cases and controls. Methods: A Norwegian case–control study on COPD including 1909 subjects used three sources of recruitment for cases (general population, hospital registry and volunteers) and two sources for controls (general population and volunteers). This resulted in six sampling combinations of cases and controls (groups A–F). We examined how the risk factors gender, age, smoking, educational level and comorbidity were associated with COPD in these six sampling groups. Results: Several exposure–disease associations were dependent on variation in sampling source, thereby demonstrating the possibility of selection bias. The theoretically most ideal sampling group is likely group A, where both cases and controls are recruited from a general population. When using group A as a reference, the groups containing either voluntary controls and/or hospital‐based cases deviated the most, suggesting higher susceptibility to selection bias in these groups. Conclusion: Recruitment from several sources made our study design vulnerable to selection bias. Our findings should bring about increased awareness to the sampling process, and encourage sampling of cases and controls from the same source population in future studies. Please cite this paper as: Sørheim I‐C, Johannessen A, Grydeland TB, Omenaas ER, Gulsvik A and Bakke PS. Case–control studies on risk factors for COPD: how does the sampling of the cases and controls affect the results? The Clinical Respiratory Journal 2010; 4: 89–96.