Harry R. Hill

Different doses of supplemental vitamin D maintain interleukin-5 without altering skeletal muscle strength: a randomized, double-blind, placebo-controlled study in vitamin D sufficient adults

BackgroundSupplemental vitamin D modulates inflammatory cytokines and skeletal muscle function, but results are inconsistent. It is unknown if these inconsistencies are dependent on the supplemental dose of vitamin D. Therefore, the purpose of this study was to identify the influence of different doses of supplemental vitamin D on inflammatory cytokines and muscular strength in young adults.MethodsMen (n = 15) and women (n = 15) received a daily placebo or vitamin D supplement (200 or 4000 IU) for 28-d during the winter. Serum 25-hydroxyvitamin D (25(OH)D), cytokine concentrations and muscular (leg) strength measurements were performed prior to and during supplementation. Statistical significance of data were assessed with a two-way (time, treatment) analysis of variance (ANOVA) with repeated measures, followed by a Tukeys Honestly Significant Difference to test multiple pairwise comparisons.ResultsUpon enrollment, 63% of the subjects were vitamin D sufficient (serum 25(OH)D ≥ 30 ng/ml). Serum 25(OH)D and interleukin (IL)-5 decreased (P < 0.05) across time in the placebo group. Supplemental vitamin D at 200 IU maintained serum 25(OH)D concentrations and increased IL-5 (P < 0.05). Supplemental vitamin D at 4000 IU increased (P < 0.05) serum 25(OH)D without altering IL-5 concentrations. Although serum 25(OH)D concentrations correlated (P < 0.05) with muscle strength, muscle strength was not changed by supplemental vitamin D.ConclusionIn young adults who were vitamin D sufficient prior to supplementation, we conclude that a low-daily dose of supplemental vitamin D prevents serum 25(OH)D and IL-5 concentration decreases, and that muscular strength does not parallel the 25(OH)D increase induced by a high-daily dose of supplemental vitamin D. Considering that IL-5 protects against viruses and bacterial infections, these findings could have a broad physiological importance regarding the ability of vitamin D sufficiency to mediate the immune systems protection against infection.

Modulation of inflammation by vitamin E and C supplementation prior to anterior cruciate ligament surgery.

Muscle atrophy commonly follows anterior cruciate ligament (ACL) injury and surgery. Proinflammatory cytokines can induce and exacerbate oxidative stress, potentiating muscle atrophy. The purpose of this study was to evaluate the influence of prior antioxidant (AO) supplementation on circulating cytokines following ACL surgery. A randomized, double-blind, placebo-controlled trial was conducted in men undergoing ACL surgery, who were randomly assigned to either: (1) AO (200 IU of vitamin E (50% d-alpha-tocopheryl acetate and 50% d-alpha-tocopherol) and 500 mg ascorbic acid), or (2) matching placebos (PL). Subjects took supplements twice daily for 2 weeks prior to and up to 12 weeks after surgery. Each subject provided five blood samples: (1) baseline (Bsl, prior to supplementation and approximately 2 weeks prior to surgery), (2) presurgery (Pre), (3) 90 min, (4) 72 h, and (5) 7 days postsurgery. Following surgery, inflammation and muscle damage increased in both groups, as assessed by increased circulating IL-6, C-reactive protein, and creatine kinase. During AO supplementation, plasma alpha-T and AA increased while gamma-T concentrations decreased significantly (P< 0.05). At 90 min the AO group displayed a significant decrease in AA, an inverse correlation between AA and (interleukin) IL-8 (r(2)= 0.50, P< 0.05), and a significantly lower IL-10 response than that of the PL group. IL-10 was significantly elevated at 90 min and 72 h in the PL group. In summary, our findings show that circulating inflammatory cytokines increase and AO supplementation attenuated the increase in IL-10 in patients post-ACL surgery.

Measurement of Antibodies to Pneumococcal Polysaccharides with Luminex xMAP Microsphere-Based Liquid Arrays

The 23 valent pneumococcal polysaccharide vaccine (PPV) is often used to assess an individuals ability to produce antibodies to polysaccharides. The Luminex xMAP microsphere-based liquid array system, when applied to the determination of antibodies to pneumococcal polysaccharides (PnPs), allows for the antibody response to the 23 serotypes to be determined simultaneously. Multiplexing saves considerable time and expense over the traditional method of testing each PnPs serotype individually by the enzyme-linked immunosorbent assay (ELISA). This chapter describes methods for (a) conjugation of poly-L: -lysine (PLL) to PnPs, (b) coupling of PnPs-PLL conjugates to Luminex microspheres, and (c) a multiplex Luminex assay for the measurement of serotype-specific IgG concentrations to pneumococcal serotypes.

Reference Laboratory Agreement on Multianalyte Pneumococcal Antibody Results: An Absolute Must!

Published ahead of print 22 May 2013 The views expressed in this Commentary do not necessarily reflect the views of the journal or of ASM.

Eliminating Subjective Reading of Microneutralization Assays in Microtiter Plates

© Automation of microneutralization assays has been difficult in the past. Typically, the assays are performed in 96 well microtiter plates, read under a light microscope, and then transcribed to a Laboratory Information System (LIS). While this method is functional and has been used for many years, it is not a very efficient method. The reading of the assay is extremely subjective. The individual reading the assay must be highly trained and disciplined to maintain a high level of quality over time. Once the reading has been performed, the data (the microtiter plate itself) from which the results were obtained are disposed. No permanent record of the microtiter plate is retained for future reference; only the final result determinations are typically recorded. There is the potential for individuals to miss troublesome patterns in the assay, where the sample should be repeated rather than have a result determination made. Often, the algorithm for result determination science [generalist | chemistry]