Five foliar constituents were measured seasonally from the three subspecies of big sagebrush in Montana. Monoterpene, crude terpenoid, and crude fat levels were lowest in the spring, increased through the summer with maximum quantities at flowering or in the fall and winter months thereafter. Crude protein and total nonstructural carbohydrates were at highest concentrations in the spring, decreased in the summer, and rose again in the fall. Sagebrush foliage consists of an external and internal component. The external material is glandular secondary metabolic products, primarily terpenoids, and cuticular waxes. The internal constituents are cell-wall polymers, protein, nonstructural carbohydrates, and lipids. A S-mhmte chloroform extraction of fresh whole leaves removed the external material (crude terpenoids) with minimal affect on the internal components. Steam distillation extracted the epidermal terpenoids and the internal nonstructural carbohydrates leaving the cuticular waxes and protein in the dry matter residue. Plants are capable of biosynthesizing a tremendous number of chemicals that have potential uses as food, fiber, fuels, and chemicals (Buchanan et al. 1978 a,b). Many of these resources, however, have been unutilized because of high costs, inadequate technology and limited knowledge of chemical composition. The rising cost of fossil fuels, particularly oil, has stimulated an interest in the chemicals and biomaterials that can bederived from plants. In the United States and Mexico research is being directed toward both native and introduced species that have evolved and adapted to the harsh semiarid and arid environments (Campos-Lopez and Roman-Alemany 1980, Johnson and Hinman 1980), where inadequate water supplies have limited agricultural development. On these drier sites, new crops could be established without affecting current food and fiber production. Big sagebrush (Artemisia tridentata) is an abundant shrub on semiarid rangelands with considerable economic and biological impact (Gifford et al. 1979). Its distribution and population densities have increased during the last century due to overgrazing of the associated grasses, fire control, and the shrubs' inherent resistance to herbivores (Morris et al. 1976, Younget al. 1979). Improvement of sagebrush-grasslands for livestock production is a desirable management practice and requires the eradication of sagebrush. This can be accomplished by a variety of techniques with variable costs and returns (Nielsen 1979). Harvesting the shrubs for their biomaterials might be a feasible alternative to destroying them and could provide some management flexibility for sagebrushgrasslands. Sagebrush biomass has two distinct components, wood and foliage. The stems and branches are primarily cell-wall polysaccharides held together with lignin and chemically similar to the wood of other angiosperms (Shafizadeh and Buckwa 1970). The foliage The authors are research associate professor, graduate student, and professor, Wood Chemistrv Laboratorv. Deoartment of Ch...
Samples of current year's growth of leaves and stems were collected in February 1983 from basin big sagebrush (Artemisia tridcntotoNuit.-), Wyoming big sagebrush (A. t. wyomingensis Beetle and Young), mountain big sagebrush (A.t. vaseyana [Rydb.] Rectle), and black sagebrush (A. nova Nels.) on a mule deer (Odocoikushemionushemionu) winter range near Cardiner, Montana. Samples were from both lightly and heavily used plants (form classes) within each taxon. Crude terpenoids were separated into 3 groups: beadspace vapors, volatile, and nonvolatile crude terpenoids. Compounds in each group are thought to stimulate the sensory organs of mule deer. Individual compounds were identified and quantified for comparison with preference ranks among taxa and between utilixation form classes. Seven compounds were selected by discrhnlnant analysis as indicators among the 4 taxa, with methacrolein+ethanol, p-cymene, and the smquiterpene lactones the most probable preference determinants. Seven other compounds were found useful for separating plants within taxa into form classes. Chemical differences between the 2 form classes, however, were less distinguishable than were those among the 4 taxa.
Therapeutic use of the anticonvulsant valproate (VPA) has been associated with a rare, but severe and often fatal hepatotoxicity. Cases usually present with lethargy, anorexia, and vomiting with rapid progression to coma. Liver histopathology is characterized by steatosis with and without necrosis. In some instances only necrosis was present. Several hypotheses of pathogenesis have been postulated. These deal mainly with biochemical systems that are known to be affected by VPA, or with the possible idiosyncratic production of toxic VPA metabolites, especially delta 4-VPA. At present, no hypothesis entirely explains the diverse characteristics of the disorder.
Earlier we showed that the structural requirements for adjuvanticity among the aminoalkyl glucosaminide 4-phosphate (AGP) class of synthetic immunostimulants may be less strict than those for other endotoxic activities, including the induction of nitric oxide synthase in murine macrophages and cytokine production in human whole blood. The known role of nitric oxide and pro-inflammatory cytokines in the activation of host defenses against infection prompted us to examine the ability of certain AGPs to enhance non-specific resistance in mice to Listeria monocytogenes and influenza infections as well as to stimulate the production of pro-inflammatory cytokines in mouse splenocytes, human PBMCs, and human U937 histiocytic lymphoma cells. Intranasal administration of RC-524 or RC-529 to mice 2 days prior to a lethal influenza challenge provided significant protection in each case. Similarly, the intravenous administration of these AGPs induced resistance to L. monocytogenes infection as measured by survival or reduction of bacteria in the spleen. Activation of the innate immune response by AGPs appears to involve activation of Toll-like receptor 4 (TLR4) because RC-524 failed to elicit a protective effect in C3H/HeJ mice which have a defect in TLR4 signaling or induce significant cytokine levels in C3H/HeJ splenocytes. Both AGPs also stimulated pro-inflammatory cytokine release in human cell cultures in a dose-dependent manner.
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