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Beekeepers who use honey bees (Apis mellifera L.) for crop pollination services, or have colonies making honey on or in close proximity to agricultural crops, are concerned about the reductions of colony foragers and ultimate weakening of their colonies. Pesticide exposure is a potential factor in the loss of foragers. During 2009-2010, we assessed changes in the field force populations of 9-10 colonies at one location per crop on each of the eight crops by counting departing foragers leaving colonies at regular intervals during the respective crop blooming periods. The number of frames of adult bees was counted before and after bloom period. For pesticide analysis, we collected dead and dying bees near the hives, returning foragers, crop flowers, trapped pollen, and corn-flowers associated with the cotton crop. The number of departing foragers changed over time in all crops except almonds; general patterns in foraging activity included declines (cotton), noticeable peaks and declines (alfalfa, blueberries, cotton, corn, and pumpkins), and increases (apples and cantaloupes). The number of adult bee frames increased or remained stable in all crops except alfalfa and cotton. A total of 53 different pesticide residues were identified in samples collected across eight crops. Hazard quotients (HQ) were calculated for the combined residues for all crop-associated samples and separately for samples of dead and dying bees. A decrease in the number of departing foragers in cotton was one of the most substantial crop-associated impacts and presented the highest pesticide risk estimated by a summed pesticide residue HQ.

Populations of pollinators are in decline worldwide. These declines are best documented in honey bees and are due to a combination of stressors. In particular, pesticides have been linked to decreased longevity and performance in honey bees; however, the molecular and physiological pathways mediating sensitivity and resistance to pesticides are not well characterized. We explored the impact of coumaphos and fluvalinate, the two most abundant and frequently detected pesticides in the hive, on genome-wide gene expression patterns of honey bee workers. We found significant changes in 1118 transcripts, including genes involved in detoxification, behavioral maturation, immunity, and nutrition. Since behavioral maturation is regulated by juvenile hormone III (JH), we examined effects of these miticides on hormone titers; while JH titers were unaffected, titers of methyl farnesoate (MF), the precursor to JH, were decreased. We further explored the association between nutrition- and pesticide-regulated gene expression patterns and demonstrated that bees fed a pollen-based diet exhibit reduced sensitivity to a third pesticide, chlorpyrifos. Finally, we demonstrated that expression levels of several of the putative pesticide detoxification genes identified in our study and previous studies are also upregulated in response to pollen feeding, suggesting that these pesticides and components in pollen modulate similar molecular response pathways. Our results demonstrate that pesticide exposure can substantially impact expression of genes involved in several core physiological pathways in honey bee workers. Additionally, there is substantial overlap in responses to pesticides and pollen-containing diets at the transcriptional level, and subsequent analyses demonstrated that pollen-based diets reduce workers' pesticide sensitivity. Thus, providing honey bees and other pollinators with high quality nutrition may improve resistance to pesticides.

This study measured part of the in-hive pesticide exposome by analyzing residues from live in-hive bees, stored pollen, and wax in migratory colonies over time and compared exposure to colony health. We summarized the pesticide burden using three different additive methods: (1) the hazard quotient (HQ), an estimate of pesticide exposure risk, (2) the total number of pesticide residues, and (3) the number of relevant residues. Despite being simplistic, these models attempt to summarize potential risk from multiple contaminations in real-world contexts. Colonies performing pollination services were subject to increased pesticide exposure compared to honey-production and holding yards. We found clear links between an increase in the total number of products in wax and colony mortality. In particular, we found that fungicides with particular modes of action increased disproportionally in wax within colonies that died. The occurrence of queen events, a significant risk factor for colony health and productivity, was positively associated with all three proxies of pesticide exposure. While our exposome summation models do not fully capture the complexities of pesticide exposure, they nonetheless help elucidate their risks to colony health. Implementing and improving such models can help identify potential pesticide risks, permitting preventative actions to improve pollinator health.

SUMMARYThe spermatozoa of ticks are anomalous in many respects: they are very large, cytoplasm-rich cells which lack a flagellum but move with a peculiar gliding motility. Their metamorphosis after deposition in the female has been well documented, but many of the subsequent events in the career of the spermatozoa are controversial or poorly documented. Our observations of motility imply that the many types of motility that have been reported (up to 5 different types in several reports) can be reduced to 2 apparently independent types of active motility: (1) gliding motility generated along the whole spermatozoon and (2) contortions of the anterior tip of the head. These types of motility appear as a consequence of sperm maturation after transfer to the female, but only become pronounced if the female has taken a recent bloodmeal. A consequence of this enhanced gliding motility after feeding is the movement of the spermatozoa out of the naturally ruptured neck of the spermatophore and up the female genital tract. This occurs without any apparent assistance from the female's musculature and likely is the prime mechanism of movement of the spermatozoa to the site of fertilization.

This chapter provides an overview of existing toxicity tests and their strengths and weaknesses, and discusses proposed modifications to existing studies, or additional studies that could address limitations in the current battery of studies. In the European Union (EU), regulatory authorities may require a bee brood feeding test to assess potential hazard of a pesticide on honey bee larvae. The chapter reports toxicity testing with some species of adult non-Apis bees with some frequency. It discusses some of the methods that have been developed to measure the potential sublethal effects of pesticides on honey bees. Laboratory toxicity tests are currently available for evaluating the potential effects of chemicals on bees. Laboratory-based studies will likely continue to focus on individual test organisms; and, although laboratory-based toxicity testing has historically focused on mortality, tests are evolving to provide insight on sublethal effects such as impaired behavior.

In many areas of the world where it is managed, the honeybee, Apis mellifera, has been plagued by diseases, pests and parasites. Of these, the parasitic mite, Varroa destructor Anderson and Truman (Acari:Varroidae), is considered by many as the most devastating. We found this mite in honeybee colonies throughout Kenya and in Tanzania for the first time in early 2009. Beekeepers surveyed were neither aware of the mite’s presence nor had they observed any negative impact on the survival and/or productivity of their bees. In March of 2009, we sampled 38 honeybee colonies (likely A. m. scutellata, and possibly A. m. scutellata hybrids) in seven locations in Central and Eastern Kenya. We employed a common sampling technique to determine mite presence/absence that utilizes powdered sugar to dislodge mites from adult bees (Macedo et al., 2002). An average of 717 ± 43 bees per colony were sampled and Varroa mites were found in all 38 colonies examined with numbers ranging from 3–108 per sample and averaging 26.3 ± 25.9 per colony. In a further similar survey (April–May, 2009) of 125 additional colonies located in the eastern, western and coastal regions of Kenya (69 colonies in 18 locations), coastal Tanzania (18 colonies in 4 locations) including Ugunja and Pemba Islands, collectively referred to as Zanzibar (likely A.m. litorea), and Western Uganda (14 colonies in 4 locations), 87% of the

The phagostimulatory response of some diabroticite cucumber beetles toward triterpene cucurbitacins is used as a model in support of an alternative hypothesis explaining the evolution of pharmacophagous feeding behavior in insects. Whereas the use of noxious compounds from nonhost sources for purposes other than nutrition or host-plant recognition (pharmacophagy) has historically been explained in terms of the ancestral host hypothesis, we suggest that the less than perfect specificity of the binding properties of some peripheral receptors provides an opportunity for novel compounds sharing the configuration and polarity of target molecules to elicit a feeding response by coincidence rather than adaptive design.

Although host-plant selection by insects is well documented, very little is known about the underlying feeding decision process. Many factors affect this decision, the most important of which are the chemosensory inputs. These inputs can be recorded using electrophysiological techniques, although there are serious limitations in interpreting the resulting records. The primary limitation is that responses to natural (plant) stimuli are often too complex to decipher, and consequently it is not known what sensory information is essential to feeding decisions. To attack this problem, we propose a systems-level approach with an operational model that can associate chemosensory inputs with behavioral outcomes across the entire host/non-host spectrum. Such a model will permit us to determine the operative rules of the feeding decision system, such as what types of sensory activity result in specific feeding behaviors, and it will help us to understand the complex, across-fiber sensory coding of responses to plant stimuli.

Taste chemoreception is essential for animals to select suitable foods. Gustatory sensilla concentrated on mouthparts, other external appendages, or the food canal are responsible for transduction of chemical stimuli into nerve signals that trigger behavioral acceptance or rejection of a potential nutrient source. Insects have primary taste neurons containing both a dendrite and a direct axonal connection to the central nervous system, whereas receptor cells and afferent neurons are separated by a synapse in vertebrates. Taste receptor proteins have not been successfully purified or cloned from any animal to date. Our recent work with western corn rootworm beetles, Diabrotica virgifera virgifera LeConte, implicates a γ-aminobutyric acid (GABA)/glycine receptor in the perception of phago-stimulants and -deterrents. GABA stimulates feeding in herbivorous members of four orders of insects. The merits of this ligand-gated receptor model for chemoreception of ‘sweet’, ‘bitter’ and other taste classes will be contrasted with those proposed from vertebrate studies. Possibly one receptor gene family allows for insect perception of both food cues and potentially toxic non-host or environmental chemicals prior to their action at critical internal sites. Studies of taste receptors offer advantages over other insect neuroreceptors by their external location which simplifies ligand pharmacodynamics and allows coupled use of behavioral and electrophysiological methods to directly link receptor pharmacology with function.

Background: Over the last two winters, there have been large-scale, unexplained losses of managed honey bee (Apis mellifera L.) colonies in the United States. In the absence of a known cause, this syndrome was named Colony Collapse Disorder (CCD) because the main trait was a rapid loss of adult worker bees. We initiated a descriptive epizootiological study in order to better characterize CCD and compare risk factor exposure between populations afflicted by and not afflicted by CCD. Methods and Principal Findings: Of 61 quantified variables (including adult bee physiology, pathogen loads, and pesticide levels), no single measure emerged as a most-likely cause of CCD. Bees in CCD colonies had higher pathogen loads and were co-infected with a greater number of pathogens than control populations, suggesting either an increased exposure to pathogens or a reduced resistance of bees toward pathogens. Levels of the synthetic acaricide coumaphos (used by beekeepers to control the parasitic mite Varroa destructor) were higher in control colonies than CCD-affected colonies. Conclusions/Significance: This is the first comprehensive survey of CCD-affected bee populations that suggests CCD involves an interaction between pathogens and other stress factors. We present evidence that this condition is contagious or the result of exposure to a common risk factor. Potentially important areas for future hypothesis-driven research, including the possible legacy effect of mite parasitism and the role of honey bee resistance to pesticides, are highlighted.

Here we describe a new phenomenon, entombed pollen, which is highly associated with increased colony mortality. Entombed pollen is sunken, capped cells amidst ‘‘normal”, uncapped cells of stored pollen, and some of the pollen contained within these cells is brick red in color. There appears to be a lack of microbial agents in the pollen, and larvae and adult bees do not have an increased rate of mortality when they are fed diets supplemented with entombed pollen in vitro, suggesting that the pollen itself is not directly responsible for increased colony mortality. However, the increased incidence of entombed pollen in reused wax comb suggests that there is a transmittable factor common to the phenomenon and colony mortality. In addition, there were elevated pesticide levels, notably of the fungicide chlorothalonil, in entombed pollen. Additional studies are needed to determine if there is a causal relationship between entombed pollen, chemical residues, and colony mortality.

We discuss an improved neural spike classification technique that augments an amplitude classifier by including temporal information. An approximation of the interspike interval histogram is used in conjunction with the amplitude probability density function to estimate the joint amplitude interval classifier.

Feeding decisions are made by the insect central nervous system based on neural input from chemoreceptors responding to phytochemical stimuli. A computational model is being developed that simulates feeding decisions by a caterpillar choosing among acceptable and unacceptable plants. Inputs to the model are electrophysiological recordings from the gustatory neurons of the caterpillar. The objectives are to determine which components of the sensory data are important in the decision process, and to elucidate the rules by which these decisions are made. The three-stage model employs: (1) artificial neural networks (ANN) for processing and classifying action potentials; (2) an adaptive algorithm for integrating data from multiple sensory organs; and (3) fuzzy logic for determining the likelihood of feeding. This third "decision module" is "trained" to associate chemosensory data with behavioral responses to the same stimulus. When trained with response to a variety of acceptable and unacceptable plants, the model can be challenged with sensory responses to a untested stimulus and asked to predict the feeding decision. These simulated decisions can then be compared with experimentally derived behavioral data to verify the accuracy of the model. Analysis of the structure (e.g., the "synaptic weights") of a successfully trained ANN provides information about which activities and interactions of the chemosensory neurons shape the decision-making process.

Discusses the implementation of an automated apparatus for recording and quantifying food choice behavior by small animals. A computer controls the apparatus by positioning a video camera over each one of twelve petri dishes. When the camera is in position, an image of the underlying dish is captured and the digitized image is returned to the computer for further processing. Within the computer a digital image processing procedure analyzes and quantifies the observed behavior.

This paper presents an Artificial Neural Network (ANN) capable of sorting neural spikes contained in a single-channel multiunit recording. The ANN performs very well when compared with Template Matching and Principal Components, two of the conventional optimal spike classification methods that have been widely used for sorting action potentials.

In insects, the summed responses of neural activity can be obtained by recording from the exterior of a taste organ (sensillum) of an intact animal. These multiunit recordings are commonly used to understand sensory and behavioral physiology. It is possible to distinguish between the neural spikes produced by these chemosensory neurons using such features as amplitude and shape. We have developed an artificial neural network (ANN) spike classifier which is capable of distinguishing among neural responses of each insect taste organ. The ANN is "trained" on prototypical spikes produced by each of the constituent neurons. It performs very well when compared with conventional optimal methods of template matching and principal components.

Tumor necrosis factor-alpha (TNF-alpha) is a mediator of severe inflammatory processes, including rheumatoid arthritis. Suppression of TNF with a soluble type I or type II receptor molecule (TNF-RI or TNF-RII) has the potential to decrease cytokine levels and modulate inflammatory diseases in humans. However, it has recently been reported that treatment of mice with a TNF-RI:Fc immunoadhesin protein augmented Gram positive infections and subsequent mortality. To determine if TNF-alpha blockade with soluble TNF-alpha receptors might alter immune system function, assays were assessed in rodents treated with a dimeric form of the p55 TNF-RI, Tumor Necrosis Factor-binding protein (TNFbp). Administration of TNFbp resulted in suppression of primary and secondary IgG antibody responses and cell-mediated immune function. No treatment-related differences were detected in immune-enhancing assays or non-specific immune function parameters. Bacterial host resistance assays with Listeria monocytogenes, Staphylococcus aureus or Escherichia coli showed an increase in tissue colony counts only with L. monocytogenes challenged animals following TNFbp administration. These results suggest that TNFbp has the capacity to inhibit adaptive immune function in experimental animal models. Studies suggest that while reducing TNF-alpha is important in controlling cytokine-dependent disease states, maintenance of a threshold level may be critical for normal immune function.

To evaluate the safety, immunogenicity, pharmacokinetics, and efficacy of intravenous administration of tumor necrosis factor binding protein (TNFbp) dimer in patients with rheumatoid arthritis (RA).This phase I/II study was a multicenter, randomized, double blind, placebo controlled, ascending dose study evaluating TNFbp dimer administered by i.v. infusion. Thirty-three patients with RA divided into 3 cohorts received TNFbp dimer (30, 100, 300 microg/kg) or placebo during a 5 min infusion at baseline and at 3 and 6 weeks; patients were followed at routine intervals after each infusion through 77 days postinfusion. Pharmacokinetics were analyzed using a log-linear regimen and comparisons were made between half-life after first, 2nd, and 3rd doses. Plasma TNFbp dimer concentrations and serum antibody levels were used in the measurement of pharmacokinetics.Administration of 30 microg/kg of TNFbp dimer was generally well tolerated; the maximum tolerated dose was 100 microg/kg. No serious adverse events were reported. A significant antibody response affected the half-life and clearance of TNFbp dimer at each dose group. Anti-TNFbp antibodies were noncytotoxic and nonagonistic. Clinical evaluations provided evidence of in vivo activity of TNFbp dimer in these patients.TNFbp dimer administered to patients with long standing RA resulted in significant antibody production to the study drug. This effect reduced the half-life and clearance of the TNFbp. This TNFbp will not be a viable option for treating patients with RA secondary to immunogenicity.

The PV-4 isostatic press has a very large working volume (98 ft{sup 3}) that was designed for routine operations at internal pressures up to 30 ksi and is, therefore, a unique and valuable component of the U.S. DOE Y-12 manufacturing capability. More than 13,000 pressing operations have been conducted since initiation of operations in September 1960. The pressure vessel portion consists of three concentric cylinders of high-strength steel with the outer two cylinders shrink-fitted on the imermost cylinder to minimize tensile stresses on the inner surface of the vessel. The third, outermost cylinder consists of two sections; each section is one-half the length of the pressure vessel. The vessel is contained within a large frame which is made of T-1 steel. In 1982 and 1983 precision strain gauges were mounted at selected locations on the frame and the outer surface of the pressure vessel to monitor the operating stresses. Where possible, locations of the gauges mounted in 1982 and 1983 were at or near the same locations as the strain gauges mounted in 1960 to monitor stresses on the frame and vessel during preoperational testing and design verification of the press. This report presents the information obtained with these strain gauges for tests conducted in September 1960 prior to any operation of the press and for the period July 1983 to August 1997. On September 8 and 9, 1960, Sturm & Krouse used 120 strain gauges on the frame and 20 strain gauges on the outer surface of the pressure vessel to measure strains in PV-4 as a function of operating pressure from O to 33 ksi. Although the design maximum operating pressure of the press was 30 ksi, to provide a safety factor for operations at 30 ksi and to assure totally elastic behavior of the steel components of the frame and pressure vessel at pressures above the design pressure, strains were also measured at operating pressures of 32 and 33 ksi. Sturm & Krouse observed that the stresses on the frame and vessel were a linear function of operating pressure over the test range from O to 33 ksi. They verified the design performance and parameters of the press and linear elastic behavior to at least 10% higher than the design operating pressure. Stresses calculated from strain gauge measurements taken between July 29, 1983, and August 5, 1997, at an operating pressure of 30 ksi are in good to excellent agreement with those obtained in September 1960 on the frame and are in excellent agreement with those obtained on the pressure vessel. In addition, slopes of the measured strain as a function of internal pressure have remained the same from preoperational testing on September 8 and 9, 1960, through August 5, 1997, the last date on which strain measurements were conducted. Also, there have been no systematic changes in the zero strain values for measurements taken with the same data acquisitions ystem. The excellent agreement of the stresses and slopes measured from 1983 to 1997 with those measured in 1960 indicates that no cracks, defects, or other flaws have developed in the pressure vessel that could affect the integrity of the pressure vessel. Also, this excellent agreement indicates that there has not been any relaxation of the original shrink-fit pressures that were employed in fabrication of the vessel. Therefore, the original shrink-fit pressures may be used for stress analysis of the pressure vessel and for estimating the fatigue life of the vessel. The excellent agreement of the stresses and slopes of strain as a function of internal pressure obtained for the period 1983 to 1997 with those obtained in 1960 are exactly as expected for the metallurgical structure of the steels of which the press frame and pressure vessel were constructed. To assure long-term integrity of the pressure vessel and that the shrink-fit pressures are not relaxed, continued monitoring of the vessel with precision strain gauges is required.

Multiunit neural activity occurs often in electrophysiological studies when utilizing extracellular electrodes. In order to estimate the activity of the individual neurons each action potential in the recording must be classified to its neuron of origin. This paper compares the accuracy of two traditional methods of action potential classification--template matching and principal components--against the performance of an artificial neural network (ANN). Both traditional methods use averages of action potential shapes to form their corresponding classifiers while the artificial neural network 'learns' a nonlinear relationship between a set of prototype action potentials and assigned classes. The set of prototypic action potentials and the assigned classes is termed the training set. The training set contained action potentials from each class which exhibited the full range of amplitude variability. The ANN provided better classification results and was more robust in analysis of across-animal data sets than either of the traditional action potential classification methods.

The topical toxicities of five commercial grade pesticides commonly sprayed in apple orchards were estimated on adult worker honey bees, Apis mellifera (L.) (Hymenoptera: Apidae) and Japanese orchard bees, Osmia cornifrons (Radoszkowski) (Hymenoptera: Megachilidae). The pesticides were acetamiprid (Assail 30SG), λ-cyhalothrin (Warrior II), dimethoate (Dimethoate 4EC), phosmet (Imidan 70W), and imidacloprid (Provado 1.6F). At least 5 doses of each chemical, diluted in distilled water, were applied to freshly-eclosed adult bees. Mortality was assessed after 48 hr. Dose-mortality regressions were analyzed by probit analysis to test the hypotheses of parallelism and equality by likelihood ratio tests. For A. mellifera, the decreasing order of toxicity at LD50 was imidacloprid, λ-cyhalothrin, dimethoate, phosmet, and acetamiprid. For O. cornifrons, the decreasing order of toxicity at LD50 was dimethoate, λ-cyhalothrin, imidacloprid, acetamiprid, and phosmet. Interaction of imidacloprid or acetamiprid with the fungicide fenbuconazole (Indar 2F) was also tested in a 1∶1 proportion for each species. Estimates of response parameters for each mixture component applied to each species were compared with dose-response data for each mixture in statistical tests of the hypothesis of independent joint action. For each mixture, the interaction of fenbuconazole (a material non-toxic to both species) was significant and positive along the entire line for the pesticide. Our results clearly show that responses of A. mellifera cannot be extrapolated to responses of O.cornifrons, and that synergism of neonicotinoid insecticides and fungicides occurs using formulated product in mixtures as they are commonly applied in apple orchards.

Before the widespread use of vitamin E in any dosage regimen can be recommended for the prevention of CAD, more information on its efficacy and adverse effects must be obtained. Unfortunately, the results of ongoing studies will not be available for several years. Until then, pharmacists can play a major role in monitoring vitamin E supplementation and educating both patients and other healthcare professionals about its potential role in decreasing the risk of coronary artery disease.

The last 400 million years or so has seen a very complex process of coevolution between plants and phytophagous insects (Ehrlich and Raven, 1964; Futuyma and Keese, 1992). Plants, apart from creating physical and mechanical barriers, rely mostly on chemical protection against insect feeding. Numerous terpenoid, alkaloid, and phenolic feeding inhibitors have evolved in the course of this arms race between plants and insects (Harborne, 1993; Rosenthal and Berenbaum, 1992; Rosenthal and Janze, 1979). The proposed process is that a random mutation within the plant genome led to the synthesis of a new compound which prevented an insect from feeding on the plant. Those insects faced with strong selection pressures exerted by plant allelochemicals evolved a mechanism or mechanisms that allowed them to overcome the deterrent or toxic effects of the new compounds. In this way some defensive compounds were successfully counteracted by one or more insect species which allowed their use as unique feeding stimulants (e.g., cucurbitacins and diabroticite beetles); however, the phagodeterrent activity remained preserved against a great many other insects. The current list of phagodeterrents is very long and their potency varies greatly among insect species, suggesting that there are many highly diverse insect—plant relationships. It appears that phagodeterrents rather than nutrients are a major force in the development of present insect—plant interactions as was proposed more than 30 years ago by Thorsteinson (Thorsteinson, 1960) and has seen renewed emphasis (Berenbaum, 1986).

Background Spray adjuvants are often applied to crops in conjunction with agricultural pesticides in order to boost the efficacy of the active ingredient(s). The adjuvants themselves are largely assumed to be biologically inert and are therefore subject to minimal scrutiny and toxicological testing by regulatory agencies. Honey bees are exposed to a wide array of pesticides as they conduct normal foraging operations, meaning that they are likely exposed to spray adjuvants as well. It was previously unknown whether these agrochemicals have any deleterious effects on honey bee behavior. Methodology/Principal Findings An improved, automated version of the proboscis extension reflex (PER) assay with a high degree of trial-to-trial reproducibility was used to measure the olfactory learning ability of honey bees treated orally with sublethal doses of the most widely used spray adjuvants on almonds in the Central Valley of California. Three different adjuvant classes (nonionic surfactants, crop oil concentrates, and organosilicone surfactants) were investigated in this study. Learning was impaired after ingestion of 20 µg organosilicone surfactant, indicating harmful effects on honey bees caused by agrochemicals previously believed to be innocuous. Organosilicones were more active than the nonionic adjuvants, while the crop oil concentrates were inactive. Ingestion was required for the tested adjuvant to have an effect on learning, as exposure via antennal contact only induced no level of impairment. Conclusions/Significance A decrease in percent conditioned response after ingestion of organosilicone surfactants has been demonstrated here for the first time. Olfactory learning is important for foraging honey bees because it allows them to exploit the most productive floral resources in an area at any given time. Impairment of this learning ability may have serious implications for foraging efficiency at the colony level, as well as potentially many social interactions. Organosilicone spray adjuvants may therefore contribute to the ongoing global decline in honey bee health.

A group of sensilla present on the maxillary galea of adult western corn rootworm,Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) beetles has been identified morphologically and physiologically to be involved in taste mediation. There are approximately 15 chemosensory hairs on each galea. Bilateral removal of these structures resulted in a significantly reduced consumption of a strongly phagostimulant triterpenoid, cucurbitacin B, and led to increased ingestion of a phagodeterrent alkaloid, strychnine. Electrophysiological responses obtained via tip-recording of galeal chemosensilla with submillimolar concentrations of host and nonhost plant compounds resulted in dose responses overlapping with the effective behavioral ranges. Cucurbitacin B was found to evoke chemosensory responses at levels as low as 0.1µM. Sinceγ-aminobutyric acid (GABA) is an agonist. (-)-β-hydrastine and strychnine are antagonists, and cucurbitacin B has been proposed to act at a separate modulatory site of classical synaptic GABA and glycine receptor-channel complexes, results reported here raise the possibility that there are peripheral chemosensory receptor sites that may resemble, functionally and structurally, synaptic receptor sites in the central nervous system.

Feeding and oviposition decisions are made by the insect central nervous system based on neural input from chemoreceptors responding to phytochemical stimuli. There are four or more chemosensory neurons in most gustatory sensilla, and each substance or plant elicits a response from more than one. The mixture of neuronal responses represents a “pattern” that is repeatable when stimulating with the same substance or plant on the same sensillum. Presumably patterns elicited by acceptable substances or plants are different from those of unacceptable ones. In attempting to understand what these input patterns mean to the animal, we have used a cybernetic approach to analyze the information content of the sensory inputs to help us understand the types of information needed for a behavioral decision. The eventual goal is to have the computer find patterns in the data that the insect uses or might use to differentiate between host plants and non-host plants. The specific question we address here is whether neural network algorithms can be “trained” with raw electrophysiological recordings as inputs, and, if so, whether they can then “recognize” similarities in other recordings submitted as “test” data.

A rare type I equivalent Monteggia lesion in a child, diaphyseal ulna and proximal radius fracture with a posterior elbow dislocation, is described, as well as the probable mechanism of injury. An excellent result was obtained with nonoperative treatment.

Tarnished plant bugs spent more time feeding than non-locomotion, locomotion, tapping, or probing on mustard, alfalfa, and cotton plants. More time was spent feeding on mustard than on any other host plant. Frequency and duration of rostral tapping and time to initiate feeding were inversely related to duration of feeding. There was no significant difference in the mean number of stylet probes on any host plant. Ingestion of sucrose was decreased from significantly greater amounts ( P = 0.05) to amounts not significant from that of water, by allowing the insects to contact a P -mercuribenzoate (PMB)-saturated disc placed over a feeding container. Ingestion was decreased to amounts significantly lower than that of water when PMB was added to sucrose below parafilm-covered feeding containers. It is suggested that differential inhibition of rostral tip and epipharyngeal chemosensilla by PMB is responsible for this reduction in ingestion. A model of the sequence of events, with sensory input involved in host selection and feeding of the tarnished plant bug, is proposed.

Selected sugars, amino acids and allelochemicals were tested over a range of concentrations to determine their effect on the ingestion rates of adult tarnished plant bugs. Experiments were performed with a two-choice bioassay technique utilizing artificial membranes. Sucrose was the most effective feeding stimulant of all the compounds tested. Glucose was an effective stimulant but was 8 times less potent than sucrose. Fructose was 50 times less potent than sucrose. Methionine and phenylalanine were the only amino acids of seven tested which stimulated feeding. Leucine produced a deterrent effect. Cotton tannin was the most effective deterrent of all allelochemicals tested and was 10 times more potent than gossypol. The quinone, 1, 4-napthoquinone, and the alkaloid, tomatine, were also effective feeding deterrents. Sinigrin and its aglycone, ethyl isothiocyanate, were among the weakest deterrents of all the allelochemicals tested. Hydroquinone was the least potent deterrent of all compounds tested. The results indicate a strong chemosensory component regulating the feeding response of the tarnished plant bug. It is suggested that this response is mediated by epipharyngeal chemosensitive sensilla.

Fall armyworm larvae, Spodoptera frugiperda (J. G. Smith), were exposed to leaf disks treated with the feeding deterrent aristolochic acid under two types of regimes: In group 1, untreated leaf tissue was replenished as soon as it was consumed; in group 2, the control tissue was not replenished. A strong feeding deterrence was evident during the early stages of the assay in both groups, but eventually declined in group 2. When the experiment was continued through a second 24 h period, the control tissue was not replenished for either group. During this second trial, group 2 larvae, which had previously fed on treated tissue, fed more rapidly on treated tissue than did group 1 larvae. Moreover, group 2 larvae fed more readily and extensively on treated tissue than they had in the first trial. The time for the onset of behavioral desensitization was determined by subtracting the median onset of feeding on untreated tissue from the median interval between when a larva finished all of the control tissue and when it started feeding on treated tissue under no-choice conditions. Once larvae began to feed on treated tissue, their rate of consumption was equal to that of larvae feeding on control tissue. A general model for determining the onset and degree of desensitization was developed. The implications of these results for future experiments aimed at determining the underlying physiological mechanisms and the use of antifeedants in plant protection are discussed. RESUME Modele general destine a quantifier la comportement d'accoutumance aux phagodissuadants L'avenir des phagodissuadants en protection des cultures depend, en particulier, de l'aptitude des insectes a devenir insensibles a ces substances. Les phagodissuadants sont classes en relatifs ou absolus, suivant que les insectes consomment les tissus traitees ou se laissent mourir de faim. Cette propriete depend beaucoup de la structure chimique, mais les parametres biologiques n'ont pas ete etudies a fond. Des experiences ont donc ete entreprises pour apprecier les effets combines de jeune et d'autres facteurs physiologiques dans l'apparition et l'evolution de la desensibilisation chez une espece polyphage: Spodoptera frugiperda (Lep. Noctuidae). Des experiences preliminaires ont montre qu'un alcaloide, l'acide aristolochique, est un puissant phagodissuadant pour S. frugiperda. Les chenilles, reparties en deux groupes experimentaux, ont toutes ete isolees et ont recu chacune deux feuilles de Phaseolus lunatus: une temoin et une traitee avec 1 000 ppm. Dans le groupe 1), les feuilles etaient remplacees des consommation; dans le groupe 2), elles ne l'etaient pas. Un puissant effet dissuadant a ete observe tout au long de l'experience pour le groupe 1); dans le groupe 2), les chenilles ont finalement consomme les feuilles traitees. L'apparition de la desensibilisation etait liee au jeune. Quelques individus ont commence a s'alimenter sur la rondelle traitee 3,5 heures apres avoir totalement consomme la rondelle temoin; le temps median du debut de cette consommation a ete de 5,7 h. Une fois la repulsion surmontee, les chenilles ont consomme le feuillage traite de la měme facon que le feuillage temoin. Les experiences ont ete recommencees avec les měmes insectes, mais sans que les feuilles temoins aient alors ete remplacees dans aucun des 2 groupes. Dans cette seconde experience, les chenilles, qui avaient precedemment consomme des feuilles traitees, sont a nouveau dissuadees lors de choix binaires; cependant elles ont mange plus rapidement les feuilles traitees, que ne l'ont fait les chenilles qui avaient dispose d'une source inepuisable de feuilles temoins. Elles se sont alimentees aussi plus facilement et plus generalement au cours de cette seconde experience qu'au cours de la premiere. Quoi qu'il en soit, les deux groupes ont presente finalement une desensibilisation. Un modele mathematique general est propose pour evaluer l'apparition et l'evolution de la desensibilisation. Les possibilites d'utilisation des phagodissuadants dans la protection des cultures sont discutees a la lumiere de ces resultats.

The behavior of adults of clerid beetle Thanasimus dubius (F.) preying upon adult southern pine beetles, Dendroctonus frontalis Zimmerman, in an arena in the laboratory is described by classifying the acts according to their consequences. A sequence of five stereotyped acts is performed by the predator: either searching or ambush, seizure of prey, alignment of prey, consumption of prey, and grooming. Handling time by the predator consists of the sums of the durations of the four acts of seizure through grooming, which was not significantly different for male and female predators, but was significantly longer for male prey (13.81 min) than for female prey (10.49 min). Consumption of prey (8–9 min) is the major component of handling time. Predators searched or waited in ambush an average of 5.8 mm before seizing a prey, and captured prey with an efficiency of 72%. Blinding predators had no significant effect on their efficiency at capturing prey. Maxillary and labial palpectomy alone or in combination significantly reduced efficiency of capture, and reduced numbers of prey consumed.

A mutant cell line (designated M.9.1.1) requiring ethanolamine for growth was derived from Chinese hamster ovary (CHO-K1) cells using 5-bromodeoxyuridine enrichment. The ethanolamine requirement was readily replaced by 20 microM phosphatidylserine and 10 microM lysophosphatidylethanolamine. When M.9.1.1 cells were supplemented with phosphatidyl[3H]serine it was rapidly taken up, and subsequently decarboxylated to form phosphatidyl[3H]ethanolamine. The incorporation of [3H]serine into phosphatidylserine in the mutant cells was 57% of that in the parental cells. Phosphatidylethanolamine synthesis from [3H]serine in the mutant cells was 35% of that in parental cells. When M.9.1.1 cells were deprived of ethanolamine for 48 h the level of phosphatidylserine decreased 34% and the level of phosphatidylethanolamine decreased 26% compared to parental cells. At the same time the rate of turnover of phosphatidylserine was reduced to half that found in parental cells. Examination of the enzymes of phosphatidylserine metabolism indicated defective phosphatidylserine synthase activity in the mutant. When exogenous phosphatidylcholine was used as the phospholipid substrate for the reaction the apparent kinetic constants were Vmax (mutant) = 5.7 pmol/min/mg protein and Vmax (parental) = 17.5 pmol/min/mg protein. Measurement of the back reaction (ATP-independent incorporation of choline into phospholipid) gave no detectable activity in the mutant cells. The data indicate that the phosphatidylcholine-dependent synthesis of phosphatidylserine is the primary lesion in M.9.1.1.

To investigate the role of MR imaging in wallerian degeneration, a series of animal models of increasingly complex peripheral nerve injury were studied by in vivo MR. Proximal tibial nerves in brown Norway rats were either crushed, transected (neurotomy), or transected and grafted with Lewis rat (allograft) or brown Norway (isograft) donor nerves. The nerves distal to the site of injury were imaged at intervals of 0-54 days after surgery. Subsequent histologic analysis was obtained and correlated with MR findings. Crush injury, neurotomy, and nerve grafting all resulted in high signal intensity along the course of the nerve observed on long TR/TE sequences, corresponding to edema and myelin breakdown from wallerian degeneration. The abnormal signal intensity resolved by 30 days after crush injury and by 45-54 days after neurotomy, when the active changes of wallerian degeneration had subsided. These changes were not seen in sham-operated rats. Our findings suggest that MR is capable of identifying traumatic neuropathy in a peripheral nerve undergoing active wallerian degeneration. The severity of injury may be reflected by the corresponding duration of signal abnormality. With the present methods, MR did not distinguish inflammatory from simple posttraumatic neuropathy.

The transferrin receptor, present on reticulocytes and nucleated cells in tissue culture, has been measured with both immunoassay techniques and transferrin binding studies. The total cellular immunoreactive receptor is rapidly lost from erythrocytes during the process of reticulocyte maturation (from as many as 400,000 molecules to20,000 molecules/reticulocyte). This event parallels the loss of cell surface transferrin binding sites and RNA content, and correlates with previous studies that have measured the decline in hemoglobin synthesis.Nonhemoglobin-producing normal human fibroblasts, which appear to have a much lower iron requirement than reticulocytes, contain similar numbers of immunoreactive receptors per cell (400,000 receptor molecules), when in an active state of proliferation. Although receptor density on fibroblasts is directly related to cell proliferation, our studies demonstrate that nonproliferating fibroblasts still retain significant numbers of immunoreactive receptors (150,000 molecules/cell) and transferrin binding sites. Since additional studies indicate that proliferating cells have increased iron uptake, a simple hypothesis would predict that the parallel increase in transferrin binding sites and total cellular immunoreactive receptor associated with proliferation is related to an increased cellular iron requirement. However, the number of immunoreactive receptor molecules and transferrin binding sites is not changed when cells are grown in iron-deficient media, or in media with added transferrin-iron. This result and the lack of marked differences in receptor number on both hemoglobin-producing and nonhemoglobin-producing cells indicate that other factors besides receptor density play major roles in the regulation of cellular iron uptake, retention, and loss.

A mutant cell line (designated M.9.1.1) requiring ethanolamine for growth was derived from Chinese hamster ovary (CHO-K1) cells using 5-bromodeoxyuridine enrichment. The ethanolamine requirement was readily replaced by 20 microM phosphatidylserine and 10 microM lysophosphatidylethanolamine. When M.9.1.1 cells were supplemented with phosphatidyl[3H]serine it was rapidly taken up, and subsequently decarboxylated to form phosphatidyl[3H]ethanolamine. The incorporation of [3H]serine into phosphatidylserine in the mutant cells was 57% of that in the parental cells. Phosphatidylethanolamine synthesis from [3H]serine in the mutant cells was 35% of that in parental cells. When M.9.1.1 cells were deprived of ethanolamine for 48 h the level of phosphatidylserine decreased 34% and the level of phosphatidylethanolamine decreased 26% compared to parental cells. At the same time the rate of turnover of phosphatidylserine was reduced to half that found in parental cells. Examination of the enzymes of phosphatidylserine metabolism indicated defective phosphatidylserine synthase activity in the mutant. When exogenous phosphatidylcholine was used as the phospholipid substrate for the reaction the apparent kinetic constants were Vmax (mutant) = 5.7 pmol/min/mg protein and Vmax (parental) = 17.5 pmol/min/mg protein. Measurement of the back reaction (ATP-independent incorporation of choline into phospholipid) gave no detectable activity in the mutant cells. The data indicate that the phosphatidylcholine-dependent synthesis of phosphatidylserine is the primary lesion in M.9.1.1.

The etiology, pathogenesis, diagnosis, and treatment of reflux esophagitis are reviewed. Reflux esophagitis is the subjective or objective response to gastroesophageal reflux (GER), which is defined as the entrance of gastroduodenal contents into the esophagus not associated with vomiting or belching. The pathogenesis of reflux esophagitis may involve a number of mechanisms, including changes in lower esophageal sphincter pressure, gastric volume, composition of the refluxate, esophageal acid clearance, and esophageal tissue resistance. The most common symptom of reflux esophagitis is heartburn. Regurgitation of fluid into the mouth, usually after bending or during the night, is an unequivocal symptom of GER. Treatment can be divided into three phases. Phase 1 involves the avoidance of certain foods and habits, elevation of the bed head, antacid, and alginic acid-antacid therapy. Phase 2 involves drug therapy with agents not yet approved by the FDA for this indication: bethanechol chloride, cimetidine, and metoclopramide hydrochloride. Bethanechol chloride 25 mg is generally given four times daily. Cimetidine is given in doses of 300-400 mg after meals and at bedtime. Metoclopramide hydrochloride is administered in doses of 10 mg before meals and at bedtime. Phase 3 is antireflux surgery. Clinical experience has shown that phase 1 therapy is successful for about 75% of all patients. Of the 25% that do not respond to phase 1 therapy, about 90% will respond to phase 2 therapy, leaving only 5-10% of all patients with this disorder who will require phase 3 treatment. Current data favor cimetidine and bethanechol over metoclopramide. The least proof of efficacy and the most frequent adverse side effects are seen with metoclopramide. Cimetidine and bethanechol appear to have similar efficacy and relatively infrequent side effects. Evidence confirming the superiority of cimetidine over bethanechol is lacking. Further research is needed to determine the optimal pharmacologic combinations and treatment regimens.