The Biogeographical Distribution of Duncecap Larkspur (Delphinium occidentale) Chemotypes and Their Potential Toxicity

Larkspurs (Delphinium spp.) are poisonous plants found on rangelands in western North America. Larkspur’s toxicity has been attributed to the norditerpenoid alkaloids, which are divided into two main structural groups: the highly toxic (N-methylsuccinimido) anthranoyllycoctonine type (MSAL type) and the less toxic 7,8-methylenedioxylycoctonine type (MDL type). Plants high in the MSAL-type alkaloids are thought to be the most toxic to cattle, and the concentrations of these alkaloids have been used as a predictor of plant toxicity. Duncecap larkspur, Delphinium occidentale, occurs throughout much of the Intermountain West and Northwestern United States. Specimens from field collections and herbaria deposits were evaluated taxonomically and chemically. Two distinct alkaloid profiles were identified: one that contains the MSAL-type alkaloids and one that contains little, if any, MSAL-type alkaloids. Thus, plants with these two alkaloid profiles should differ in their toxic potential. Each profile was unique in its geographical distribution. These findings have important implications in grazing management decisions on D. occidentale-infested rangelands, and they demonstrate that botanical classification alone is not a good indicator to determine the toxic risk of D. occidentale.     

Effects of gender, construct type, occupational information, and career relevance on vocational differentiation.

A study was designed to replicate and extend previous research on 1 aspect of vocational structure, vocational differentiation (VOD). Results of a 2 (gender)?×?2 (occupational information)?×?2 (construct type)?×?3 (career relevance) between-Ss study revealed 2 sets of noteworthy findings. First, results replicated previous findings concerning the impact of each of these factors on levels of VOD. Higher levels of VOD were found in men than were found in women and were related to the use of personal constructs when Ss judged highly irrelevant career alternatives. Second, these effects were qualified by interaction between construct type (personal and provided) and career relevance (high, mixed, and low). Personally elicited constructs were used with greater differentiation than were standard provided ones only when participants evaluated highly relevant career alternatives. This effect challenges long-standing assumptions regarding differences between personal and provided vocational constructs, and the implications of this are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synthetic hydrogels 2. Polymerization induced phase separation in acrylamide systems

Acrylamide hydrogels were synthesized in the presence of various non-solvents for linear polyacrylamide to examine phase separation during polymerization. The process was found to be dependent upon the segmental volume, the chemical structure, and the concentration of the non-solvent. The concept of conversion-phase diagram for linear polymer is introduced and used qualitatively to understand polymerization induced phase separation (PIPS), and to predict the onset of PIPS during hydrogel synthesis.     

Diffusion MR in Biological Systems: Tissue Compartments and Exchange

The processes of diffusion in multi-compartmental tissue models are discussed using an analytical model of diffusion with exchange. Diffusion in the intracellular compartment has been found to be highly restricted, with the apparent diffusion coefficient (ADC₁) dependent on the experimental parameters. Extracellular diffusion mediated by tortuosity, depends on tissue geometry, but not on the experimental conditions. Both the intra- and extracellular diffusion can be anisotropic and exhibit non-monoexponential behavior. The cell membrane permeability is shown to significantly influence the diffusion measurement in tissues. In consequence, the phenomenological, bi-exponential models of diffusion cannot directly estimate the intrinsic characteristics of intra- and extracellular water. The mechanisms of the ADC decrease after stroke are also discussed.     

A constant humidity air supply system for pilot scale applications

This paper outlines the development of an apparatus to supply air with both controlled temperature and relative humidity, at a variety of flow rates up to 114 L min⁻¹. To achieve adjustable constant relative humidities in the air, the two-pressure principle was used. This method involved saturating the air at a higher pressure, and then passing the air through a pressure release valve to the lower working pressure to achieve the desired humidity, while controlling the temperature to the desired level. The absolute pressure when the saturation is achieved determines the humidity of the final air. Standard design procedures were followed to ensure the air approached saturation in the pressurized column and that the amount of water was sufficient to make sure the columns would not run out of water during an experiment. The problems encountered included a pressure fluctuation coming from the compressor through the pressure regulator, and a regular fluctuation in the temperature of the water, within a 90 min period, when the water temperature was used to control the air temperature exiting the column. These problems were overcome by using two-pressure regulators on the air supply and by controlling the temperature of the water rather than the air temperature. The result was a stable but adjustable temperature and relative humidity air supply.     

Suppression of human melanoma metastasis following introduction of chromosome 6 is independent of NME1 (Nm23)

BACKGROUND: Nasal immunotherapy with single allergen extracts, following premedication with cromolyn, has been reported to be effective in treating seasonal and perennial allergic rhinitis. METHODS: We conducted a double-blind, placebo-controlled study to assess the efficacy, tolerability, and mechanism of action of nasal immunotherapy for allergic rhinitis caused by weed pollens from three unrelated families. Twenty-seven weed-allergic patients underwent baseline nasal provocation and titrated skin test with a mixed weed extract containing ragweed, sage, and Chenopod extracts. Patients were randomized to receive either mixed weed extract or placebo. Nasal immunotherapy was self-administered daily to alternate nostrils preceded by 5.2 mg intranasal cromolyn. Beginning with 1:2500 wt/vol the concentration was increased to 1:10 wt/vol over an average period of 36 days. The maintenance dose (1:10 wt/vol) was administered daily for 12 to 16 weeks through the weed pollen season. Patients recorded nasal and eye symptoms and the use of rescue medications throughout the study. A nasal lavage for cytokine levels and nasal scraping with Rhinoprobe for nasal cytology were performed at the peak of the weed season. Nasal provocation and titrated skin tests with mixed weed extract were repeated after the weed season. Nasal lavage and scraping were also performed before and 24 hours after the final nasal provocation. RESULTS: During the peak weeks of the weed season the group receiving mixed weed extract by nasal instillation, compared with those treated with placebo, had significantly lower total nasal symptom scores, total eye symptom scores, and symptom medication scores. There were no significant differences in the nasal cytology or cytokines levels between the two groups, except for elevated IL-10 in the nasal lavage in the treated group at the peak of the season. Nasal symptoms and medication use were higher preseasonally in the active treatment group. CONCLUSION: Nasal immunotherapy with aqueous mixed weed extract administered with cromolyn sodium pretreatment for 17 to 21 weeks was effective in reducing both nasal and ocular symptoms of weed pollen-induced allergic rhinitis. There were increased nasal symptoms in the treated group preseasonally.     

Involvement of calcium and L-type channels in nicotine-induced antinociception

The nature of the signaling process activated by neuronal nicotinic receptors has not been fully defined; however, several recent studies have implicated the involvement of calcium ion fluxes in the response to nicotine on a cellular level. Alteration of nicotine-induced antinociception in mice after systemic administration was therefore investigated in the presence of several drugs that increase intracellular calcium. Calcium, (+/-)-BAYK 8644, thapsigargin, glyburide and A23187 administered intrathecally (i.t.) were found to enhance nicotine-induced antinociception by shifting its dose-response curve to the left. Conversely, i.t. administration of agents which decrease intracellular calcium, such as EGTA and alpha-calcitonin gene-related peptide, blocked nicotine-induced antinociception. These findings support a role for spinal intracellular calcium in the pharmacological effects of nicotine. Additionally, blockade of antinociception by nimodipine and nifedipine indicates that a L-type calcium channel is involved in nicotine's effect. However, nicotine did not compete for [3H] nitrendipine binding. Intrathecal administration of mecamylamine, a nicotinic antagonist, resulted in a blockade of antinociception produced by the i.t. injection of thapsigargin, A23187, calcium and (+/-)-BAYK 8644. The mechanism of mecamylamine's antagonism of nicotine is uncertain. However, these results suggest that mecamylamine blocks the effects of drugs which increase intracellular calcium by either a modulation of intracellular calcium-dependent mechanisms or a blockade of calcium channels. Thus, mecamylamine could modulate a calcium signaling process secondary to receptor activation resulting in blockade of antinociception produced by diverse agents.     

High-power, spectrally coherent array of monolithic flaredamplifier-master oscillator power amplifiers (MFA-MOPAs)

A monolithically integrated array of InGaAs/AlGaAs flared amplifiers driven by a single DBR laser through a power splitter network is described. This architecture is capable of providing single-mode, diffraction-limited performance from each emitter and is scalable to unprecedented power levels. Over 20 W of pulsed, spectrally coherent emission is generated at 955 nm from a 4-element array, and 39 W is obtained from an 8-element array     

Changing the rape-supportive attitudes of traditional and nontraditional male and female college students.

This study tested whether individuals possessing traditional sex role attitudes could have their rape-related attitudes influenced by a psychoeducational intervention that has been effective with less traditional individuals. Male and female undergraduates (N?=?245) were classified on the basis of their sex role traditionality and received the intervention or served as no-treatment controls. A multivariate analysis of variance revealed that intervention recipients adhered less to rape myths and expressed less rape-supportive attitudes than did controls. Participants were subsequently contacted with a phone appeal regarding women's safety projects that they thought was unrelated to the experiment. On 1 phone appeal measure, experimental participants' responses were significantly less rape-supportive than were control participants' responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)