Evaluation of ruminal evacuation versus marker dilution procedures for estimating particulate passage rate

Call number: LD2668 .T4 ASI 1988 B44Master of ScienceAnimal Sciences and Industr

Anchoring Phenomena with Light and Contact Forces

OpenSciEd is a curriculum designed for the NGSS based on science storylines, phenomena-based, coherent from students’ perspective, driven by evidence, collaborative, and equitable. Instructional units for Grades 6-8 are available and will expand to include elementary through high school. Experience anchoring phenomena from Grade 6.1 Light & Matter and Grade 8.1 Contact Forces. UNI Science Education will be supporting the use of OpenSciEd with resources and future professional development

How to Integrate STEM in Your Classroom with NGSS FOSS

STEM Enrichment NGSS Modules including Variables & Design (Grades 6-8), Sound & Design (Grades 3-5), and Forces in Action (Grades K-2) are now available. Join us as we explore these STEM Enrichment NGSS Modules and discuss how they can be used in your classroom. NGSS Modules Observing Nature (Grade Pre-K) and Weather and Seasons (Grade K) will also be available to be explored and reviewed

The human macrophage mannose receptor directs Mycobacterium tuberculosis lipoarabinomannan-mediated phagosome biogenesis

Mycobacterium tuberculosis (M.tb) survives in macrophages in part by limiting phagosome–lysosome (P-L) fusion. M.tb mannose-capped lipoarabinomannan (ManLAM) blocks phagosome maturation. The pattern recognition mannose receptor (MR) binds to the ManLAM mannose caps and mediates phagocytosis of bacilli by human macrophages. Using quantitative electron and confocal microscopy, we report that engagement of the MR by ManLAM during the phagocytic process is a key step in limiting P-L fusion. P-L fusion of ManLAM microspheres was significantly reduced in human macrophages and an MR-expressing cell line but not in monocytes that lack the receptor. Moreover, reversal of P-L fusion inhibition occurred with MR blockade. Inhibition of P-L fusion did not occur with entry via Fcγ receptors or dendritic cell–specific intracellular adhesion molecule 3 grabbing nonintegrin, or with phosphatidylinositol-capped lipoarabinomannan. The ManLAM mannose cap structures were necessary in limiting P-L fusion, and the intact molecule was required to maintain this phenotype. Finally, MR blockade during phagocytosis of virulent M.tb led to a reversal of P-L fusion inhibition in human macrophages (84.0 ± 5.1% vs. 38.6 ± 0.6%). Thus, engagement of the MR by ManLAM during the phagocytic process directs M.tb to its initial phagosomal niche, thereby enhancing survival in human macrophages

In vitro supplementation with different tocopherol homologues can affect the function of immune cells in old mice

Alpha-tocopherol (T) is the most common form of vitamin E in plasma and tissues. Alpha-T is also believed to be superior to its homologues β-T, γ-T, and δ-T in antioxidant activity. Biological activity of α-T has been intensively studied in a number of bodily systems. In contrast, the other homologues have received little attention beyond the evaluation of their relative antioxidant activity. We as well as others have previously shown that α-T can enhance cell-mediated immune function of aged animals and humans. Gamma-T is a principal form of vitamin E in the American diet and some cooking oils contain substantial amount of β-T and δ-T. Thus it is of public health interest to compare their biological effects with that of α-T in various systems. In this study, we used an in vitro supplementation protocol to determine immunologic effects of these T homologues on murine splenocytes. The results showed that all four T homologues enhance both spontaneous and mitogen-stimulated lymphocyte proliferation (LP) and the maximal enhancement produced by them was of the same magnitude. The dose range to produce maximal enhancement varied with different homologues. The efficiency was in the order of β-T ~ δ-T \u3e γ-T \u3e α-T. Interestingly, at 50 (optimal for α-T) and 150 μmol/L, while α-T enhanced LP, all the other homologues inhibited LP. This inhibition was found to be due to their cytotoxicity at these levels. T homologues had a differential effect on interleukin (IL)-2 and prostaglandin (PG)E2 production. IL-2 production by mouse splenocytes was not affected by α-T or β-T, but was increased by γ-T and δ-T. All T homologues, except for β-T, inhibited PGE2 production by mouse peritoneal macrophages. Cyclooxygenase activity, however, was inhibited by all T homologues. Analysis of cellular T showed that these T homologues were differentially incorporated into the cells in the order of β-T ~ δ-T \u3e γ-T \u3e α-T. Thus, all the T homologues enhance LP. However, the dose required to reach maximal enhancement varies among the homologues. On the other hand, they have a differential effect on IL-2 and PGE2 production. The difference in nature and magnitude of the effect on immune function does not correlate with their reported relative antioxidant activity and might be due to minor differences in their structure important to their other biological activities. Copyright (C) 2000 Elsevier Science Inc