Potential Roles of Peroxidases in Caenorhabditis Elegans Innate Immunity

The production of ROS (reactive oxygen species) in response to pathogen detection is a rapid, nonspecific response that is evolutionarily conserved from nematodes to humans. ROS serve as direct and indirect effectors of innate and adaptive immunity. In Caenorhabditis elegans, a ROS burst is observed during infection and is mediated by the dual oxidase BLI-3, which produces H2O2. RNAi (RNA interference) to reduce the amount of BLI-3 results in a significant increase in susceptibility to pathogens, suggesting BLI-3 has a role in the immune response. However, H2O2 by itself is not a potent antimicrobial and in other systems is converted to a more potent oxidant by an affiliated peroxidase. During my work, I have characterized a group of previously unstudied peroxidases in C. elegans and determined their involvement in the host immune response to Enterococcus faecalis. In particular, I focused on SKPO-1 (ShkT-containing peroxidase) and how it contributes to the host immune response with respect to BLI-3. By RNAi and skpo-1 mutant analysis, I determined that SKPO-1 is involved in the host immune response during E. faecalis infection. By tissue-specific RNAi, I determined that SKPO-1 is functionally active in the hypodermis and required for wild type resistance to infection. Additionally, by immunohistochemistry, I observed that SKPO-1 is only expressed in the hypodermis and that its protein levels do not change in response to E. faecalis. In support of SKPO-1 acting as a peroxidase, I observed a significant increase in H2O2 levels when expression of the gene was reduced by RNAi. The increased H2O2 was observed only during infection and was BLI-3-dependent. Thus, I have characterized a likely BLI-3/SKPO-1 system, potentially similar to the oxidative burst systems present in higher eukaryotes

Direct observation of interface instability during crystal growth

The general aim of this investigation was to study interface stability and solute segregation phenomena during crystallization of a model system. Emphasis was to be placed on direct observational studies partly because this offered the possibility at a later stage of performing related experiments under substantially convection-free conditions in the space shuttle. The major achievements described in this report are: (1) the development of a new model system for fundamental studies of crystal growth from the melt and the measurement of a range of material parameters necessary for comparison of experiment with theory. (2) The introduction of a new method of measuring segregation coefficient using absorption of a laser beam by the liquid phase. (3) The comparison of segregation in crystals grown by gradient freezing and by pulling from the melt. (4) The introduction into the theory of solute segregation of an interface field term and comparison with experiment. (5) The introduction of the interface field term into the theories of constitutional supercooling and morphological stability and assessment of its importance

The Translational Apparatus of Plastids and Its Role in Plant Development

Chloroplasts (plastids) possess a genome and their own machinery to express it. Translation in plastids occurs on bacterial-type 70S ribosomes utilizing a set of tRNAs that is entirely encoded in the plastid genome. In recent years, the components of the chloroplast translational apparatus have been intensely studied by proteomic approaches and by reverse genetics in the model systems tobacco (plastid-encoded components) and Arabidopsis (nucleus-encoded components). This work has provided important new insights into the structure, function, and biogenesis of chloroplast ribosomes, and also has shed fresh light on the molecular mechanisms of the translation process in plastids. In addition, mutants affected in plastid translation have yielded strong genetic evidence for chloroplast genes and gene products influencing plant development at various levels, presumably via retrograde signaling pathway(s). In this review, we describe recent progress with the functional analysis of components of the chloroplast translational machinery and discuss the currently available evidence that supports a significant impact of plastid translational activity on plant anatomy and morphology

Fatigue testing a plurality of test specimens and method

Described is a fatigue testing apparatus for simultaneously subjecting a plurality of material test specimens to cyclical tension loading to determine the fatigue strength of the material. The fatigue testing apparatus includes a pulling head having cylinders defined therein which carry reciprocating pistons. The reciprocation of the pistons is determined by cyclical supplies of pressurized fluid to the cylinders. Piston rods extend from the pistons through the pulling head and are attachable to one end of the test specimens, the other end of the test specimens being attachable to a fixed base, causing test specimens attached between the piston rods and the base to be subjected to cyclical tension loading. Because all the cylinders share a common pressurized fluid supply, the breaking of a test specimen does not substantially affect the pressure of the fluid supplied to the other cylinders nor the tension applied to the other test specimens

ARE THERE ELECTRICAL DEVICES THAT CAN MEASURE THE BODY'S ENERGY STATE CHANGE TO AN ACUPUNCTURE TREATMENT? Part l, The Meridian Stress Assessment (MSA-21J Device

The general field of energy medicine is growing strongly but is still in great need of reliable monitoring instruments to assess the relative energetic state of humans with respect to a health/pathology ratio. Two commercial instruments: Bio-Meridian's MSA-21 and Korotkov's GDV were selected for an in-parallel study of the following question, "Can they meaningfully discriminate the effects of acupuncture treatment on the body's energy state?" In this part 1 paper we discuss the results obtained by Bio-Meridian' MSA-21. the experimental design was to determine if the MSA-21 and the GDV could discern a quantifiable difference between an authentic acupuncture session and a sham acupuncture session for 34 subjects. The single research hypothesis was, "If energy is added to andlor redistributed in the body via true acupuncture needling, as contrasted with sham acupuncture needling, a worthy measurement instrument must (at least) be able to discriminate this energy change contrast in a statistically significant fashion." Indeed, the MSA-21 instrument passed this test in good order and provided much useful adjunct information as well

Frequency dependence of microflows upon acoustic interactions with fluids

Rayleigh surface acoustic waves (SAWs), generated on piezoelectric substrates, can interact with liquids to generate fast streaming flows. Although studied extensively, mainly phenomenologically, the effect of the SAW frequency on streaming in fluids in constrained volumes is not fully understood, resulting in sub-optimal correlations between models and experimental observations. Using microfluidic structures to reproducibly define the fluid volume, we use recent advances modeling the body force generated by SAWs to develop a deeper understanding of the effect of acoustic frequency on the magnitude of streaming flows. We implement this as a new predictive tool using a finite element model of fluid motion to establish optimized conditions for streaming. The model is corroborated experimentally over a range of different acoustic excitation frequencies enabling us to validate a design tool, linking microfluidic channel dimensions with frequencies and streaming efficiencies. We show that in typical microfluidic chambers, the length and height of the chamber are critical in determining the optimum frequency, with smaller geometries requiring higher frequencies

Tree Growth and Cattle Weight Gain in a Ponderosa Pine System

Integrated timber and livestock systems (silvopastoral) are common in several regions of the United States. Grazing of three timber stands in eastern Nebraska showed no signs of tree damage due to rubbing or soil compaction. Steer gains were lower under the silvopastoral system compared to a typical pasture system (1.05 lb/day versus 1.70 lb/day). Growth of timber in silvopastoral stands was reduced (35.0 cubic feet per year versus 37.8 cubic feet per year); however, total productivity of the silvopastoral system (timber plus livestock) was greater ($20.98/acre) than with traditional timber systems

Exercise-induced diaphragm fatigue in a Paralympic champion rower with spinal cord injury

Introduction. The aim of this case report was to determine whether maximal upper-body exercise was sufficient to induce diaphragm fatigue in a Paralympic champion adaptive rower with low-lesion spinal cord injury (SCI). Case Presentation. An elite arms-only oarsman (age 28 y, stature 1.89 m, mass 90.4 kg) with motor-complete SCI (T12) performed a 1000 m time-trial on an adapted rowing ergometer. Exercise measurements comprised pulmonary ventilation and gas exchange, diaphragm EMG-derived indices of neural respiratory drive and intrathoracic pressure-derived indices of respiratory mechanics. Diaphragm fatigue was assessed by measuring pre- to post-exercise changes in the twitch transdiaphragmatic pressure (Pdi,tw) response to anterolateral magnetic stimulation of the phrenic nerves. The time-trial (248 ± 25 W, 3.9 min) elicited a peak O2 uptake of 3.46 L·min−1 and a peak pulmonary ventilation of 150 L·min−1 (57% MVV). Breath-to-stroke ratio was 1:1 during the initial 400 m and 2:1 thereafter. The ratio of inspiratory transdiaphragmatic pressure to diaphragm EMG (neuromuscular efficiency) fell from rest to 600 m (16.0 vs. 3.0). Potentiated Pdi,tw was substantially reduced (−33%) at 15-20 min post-exercise, with only partial recovery (−12%) at 30-35 min. Conclusions. This is the first report of exercise-induced diaphragm fatigue in SCI. The decrease in diaphragm neuromuscular efficiency during exercise suggests that the fatigue was partly due to factors independent of ventilation (e.g., posture and locomotion)

High-level expression of the HIV entry inhibitor griffithsin from the plastid genome and retention of biological activity in dried tobacco leaves

The global HIV epidemic continues to grow, with 1.8 million new infections occurring per year. In the absence of a cure and an AIDS vaccine, there is a pressing need to prevent new infections in order to curb the disease. Topical microbicides that block viral entry into human cells can potentially prevent HIV infection. The antiviral lectin griffithsin has been identified as a highly potent inhibitor of HIV entry into human cells. Here we have explored the possibility to use transplastomic plants as an inexpensive production platform for griffithsin. We show that griffithsin accumulates in stably transformed tobacco chloroplasts to up to 5% of the total soluble protein of the plant. Griffithsin can be easily purified from leaf material and shows similarly high virus neutralization activity as griffithsin protein recombinantly expressed in bacteria. We also show that dried tobacco provides a storable source material for griffithsin purification, thus enabling quick scale-up of production on demand

Finite size effects with variable range exchange coupling in thin-film Pd/Fe/Pd trilayers

The magnetic properties of thin-film Pd/Fe/Pd trilayers in which an embedded ~1.5 A-thick ultrathin layer of Fe induces ferromagnetism in the surrounding Pd have been investigated. The thickness of the ferromagnetic trilayer is controlled by varying the thickness of the top Pd layer over a range from 8 A to 56 A. As the thickness of the top Pd layer decreases, or equivalently as the embedded Fe layer moves closer to the top surface, the saturated magnetization normalized to area and the Curie temperature decrease whereas the coercivity increases. These thickness-dependent observations for proximity-polarized thin-film Pd are qualitatively consistent with finite size effects that are well known for regular thin-film ferromagnets. The critical exponent $\beta$ of the order parameter (magnetization) is found to approach the mean field value of 0.5 as the thickness of the top Pd layer increases. The functional forms for the thickness dependences, which are strongly modified by the nonuniform exchange interaction in the polarized Pd, provide important new insights to understanding nanomagnetism in two-dimensions.Comment: 14 pages, 5 figures, submitted to JMM