Michael M. McChesney

Recombinant Bacille Calmette-Guérin Expressing the Measles Virus Nucleoprotein Protects Infant Rhesus Macaques from Measles Virus Pneumonia

Measles virus infection continues to be a major cause of infant mortality. There is a need for a measles vaccine that can be administered at birth in the presence of maternal neutralizing antibody. Infant rhesus monkeys were immunized with recombinant bacille Calmette-Guérin expressing the full-length measles virus nucleoprotein (BCG-N) and subsequently challenged with measles virus. Nucleoprotein-specific lymphocyte proliferative responses were detected in the absence of anti-N antibody after vaccination. Vaccination with BCG-N did not prevent systemic measles virus infection; however, there was a significant reduction of lung inflammation after challenge. Virus titers in lymph nodes were significantly lower, and the duration of nasopharyngeal viral shedding was shorter in some vaccinated monkeys after challenge. These results suggest that measles virus-specific T cells were primed by BCG-N vaccination and that they prevented virus-induced lung pathology.

Influences of blood sampling procedures on basal hypothalamic‐pituitary‐adrenal hormone levels and leukocyte values in rhesus macaques (Macaca mulatta)

Abstract: The influences of housing location and temporal factors on the results of blood sampling were examined to determine their contributions to levels of hypothalamic‐pituitary‐adrenal hormones, as well as leukocyte subset counts from peripheral blood in rhesus monkeys. Differences in housing location and the amount of room disturbance associated with blood sampling have a significant impact on cell counts, but not on ACTH or Cortisol levels.

A multiresidue method by high performance liquid chromatography-based fractionation and gas chromatographic determination of trace levels of pesticides in air and water

A multiresidue analytical method is described for pesticides, transformation products, and related toxicants based upon high performance liquid Chromatographic (HPLC) fractionation of extracted residue on a Partisil® silica gel normal phase column followed by selective-detector gas chromatographic (GC) determination of components in each fraction. The HPLC mobile phase gradient (hexane to methylt-butyl ether) gave good Chromatographic efficiency, resolution, reproducibility and recovery for 61 test compounds, and allowed for collection in four fractions spanning polarities from low polarity organochlorine compounds (fraction 1) to polarN-methylcarbamates and organophosphorus oxons (fraction 4). The multiresidue method was developed for use with air samples collected on XAD-4® and related trapping agents, and water samples extracted with methylene chloride. Detection limits estimated from spiking experiments were generally 0.3–1 ng/m3 for high-volume air samples, and 0.01–0.1 μg/L for one-liter water samples. Applications were made to determination of pesticides in fogwater and air samples.

Separation of paraoxon and mipafox sensitive esterases by sucrose density gradient sedimentation

Paraoxon- and mipafox-sensitive phenyl valerate (PV) hydrolases found in chicken nervous tissue were solubilized by Triton X-100 and separated by sucrose density gradient centrifugation. Enzyme activity from chick embryo brain with properties of neurotoxic esterase (NTE, insensitive to 40 microM paraoxon, sensitive to 50 microM mipafox) migrated in a 9S peak.

Studies of the distribution, drift, and volatilization of diazinon resulting from spray application to a dormant peach orchard

Abstract An experiment was conducted to determine the spray distribution, spray drift, and volatilization of diazinon applied in the conventional manner with an air-blast sprayer to a dormant peach orchard. Copper hydroxide and a dormant oil were applied along with the diazinon. Soil samples and tree rinse samples were used to determine the distribution in the orchard. Airborne losses were calculated by the integrated horizontal flux method from measurements of wind speed and pesticide concentration profiles obtained during and for several days following application. Diazinon was not distributed evenly between the trees and the soil in the orchard according to their relative areas. Most of the diazinon accounted for was found to be on the soil. The residue on the soil dissipated with a 19 day half life. Application drift losses were small compared to long-term volatilization losses, and we conclude that most of the diazinon in Californias Central Valley atmosphere during the dormant spray season results from volatilization. This result has important implications for designing strategies for controlling inadvertent contamination of other crops and the environment.

Models for assessing the volatilization of herbicides applied to flooded rice fields

Abstract Volatilization rates of MCPA, thiobencarb, and molinate from water were calculated using the EXAMS aquatic fate computer model, and measured in a laboratory chamber and in flooded rice fields. A fair to good correlation was obtained between EXAMS-calculated and chamber-measured rates for all three herbicides. Field-measured values correlated well with chamber-measured rates for thiobencarb and molinate. For MCPA, field-measured values were much higher than expected for volatilization from water alone. In this case, the presence of plant and other surface residues in the field made the major contribution to observed volatilization. For MCPA, 4-chloro-o-cresol flux was comparable to that of the parent herbicide.

Residues of toxaphene, DEF, and paraquat in plant parts and gin waste from a treated cotton field.

The origin and fate of the gin waste residues of three chemicals—toxaphene, DEF, and paraquat—used frequently in cotton production in California were studied. Residues were determined for foliage and bolls in the live plants, for lint and seed in harvested seed cotton, and for gin waste and its lint and non-lint components, following commercial treatments to the cotton crop. Gin waste residues were followed during five months of open storage to ascertain dissipation rates in a typical waste sample. Relatively high residues of each of the three chemicals persisted at harvest, during storage prior to ginning, and in stored gin waste. The major proportion of gin waste residue was associated with the non-lint components—leaf parts, burrs, stems and other foreign matter. Average stored gin waste residues in the lint and non-lint components were 13 and 60, 11 and 58, and 5 and 10 ppm for toxaphene, DEF, and paraquat, respectively, during the open storage period.

Chemical residues during screening, composting, and soil incorporation of cotton gin waste

Abstract Residues of pesticides and harvest aid chemicals (defoliants) were studied in the products of ginning of cotton. Particular emphasis was on residue partitioning during the mechanical separation of cotton gin waste into its clean (primarily lint) and fines (primarily dirt and plant parts) fractions following rotating screen separation. The higher residues were associated with the fines fraction among the two chemicals (DEF and dicofol) studied in this regard. The behaviour of residues of five chemicals was studied during aerobic and semi‐anaerobic Composting of both whole gin waste and the fines fraction. Propargite, methidathion, and chlorate residues declined significantly during both composting treatments while DEF and paraquat were stable to composting, when composted gin wastes were amended to field soil, residue levels were generally very low to undetectable in the soil, indicating little potential hazard for a composting‐amendment operation. Analysis of air samples indicated that only the s...

Structure of aspecioside from the monarch butterfly larvae foodplants Asclepias speciosa and A. syriaca

Aspecioside, a 7β,8β-epoxycardenolide glycoside isolated from Asclepias speciosa(Asclepiadaceae), has been shown by 400 MHz 1H n.m.r., 13C n.m.r., mass spectrometry, and biogenetic considerations to be 12β-hydroxy-5α-tanghinigenin-3-(6-deoxy-β-D-allopyranoside). It is also found in A. syriaca.