Disruption of NREM sleep and sleep-related spatial memory consolidation in mice lacking adult hippocampal neurogenesis.

Cellular plasticity at the structural level and sleep at the behavioural level are both essential for memory formation. The link between the two is not well understood. A functional connection between adult neurogenesis and hippocampus-dependent memory consolidation during NREM sleep has been hypothesized but not experimentally shown. Here, we present evidence that during a three-day learning session in the Morris water maze task a genetic knockout model of adult neurogenesis (Cyclin D2-/-) showed changes in sleep macro- and microstructure. Sleep EEG analyses revealed a lower total sleep time and NREM fraction in Cyclin D2-/- mice as well as an impairment of sleep specific neuronal oscillations that are associated with memory consolidation. Better performance in the memory task was associated with specific sleep parameters in wild-type, but not in Cyclin D2-/- mice. In wild-type animals the number of proliferating cells correlated with the amount of NREM sleep. The lack of adult neurogenesis led to changes in sleep architecture and oscillations that represent the dialog between hippocampus and neocortex during sleep. We suggest that adult neurogenesis-as a key event of hippocampal plasticity-might play an important role for sleep-dependent memory consolidation and modulates learning-induced changes of sleep macro- and microstructure.

Chapter One - Ubiquitination and Deubiquitination of G Protein-Coupled Receptors.

The seven-transmembrane containing G protein-coupled receptors (GPCRs) constitute the largest family of cell-surface receptors. Transmembrane signaling by GPCRs is fundamental to many aspects of physiology including vision, olfaction, cardiovascular, and reproductive functions as well as pain, behavior and psychomotor responses. The duration and magnitude of signal transduction is tightly controlled by a series of coordinated trafficking events that regulate the cell-surface expression of GPCRs at the plasma membrane. Moreover, the intracellular trafficking profiles of GPCRs can correlate with the signaling efficacy and efficiency triggered by the extracellular stimuli that activate GPCRs. Of the various molecular mechanisms that impart selectivity, sensitivity and strength of transmembrane signaling, ubiquitination of the receptor protein plays an important role because it defines both trafficking and signaling properties of the activated GPCR. Ubiquitination of proteins was originally discovered in the context of lysosome-independent degradation of cytosolic proteins by the 26S proteasome; however a large body of work suggests that ubiquitination also orchestrates the downregulation of membrane proteins in the lysosomes. In the case of GPCRs, such ubiquitin-mediated lysosomal degradation engenders long-term desensitization of transmembrane signaling. To date about 40 GPCRs are known to be ubiquitinated. For many GPCRs, ubiquitination plays a major role in postendocytic trafficking and sorting to the lysosomes. This chapter will focus on the patterns and functional roles of GPCR ubiquitination, and will describe various molecular mechanisms involved in GPCR ubiquitination.

Establishment of an in vitro method for evaluating whitefly resistance in tomato.

An accurate and simple evaluation method is crucial for identifying whitefly resistance in tomato breeding. We developed an in vitro method for evaluating resistance of tomato leaves and tested this on wild and cultivated tomato varieties. We found that young leaves observed for whitefly oviposition after 8 hours provided appropriate comparative conditions. This method effectively distinguished resistance among tomato cultivars and wild species and also demonstrated significant difference in oviposition rates among leaf positions on susceptible cultivars. The in vitro test was as precise as in vivo test using intact plants and had advantages over in vivo test, and can be used for evaluating resistance in large populations.

Endogenous lung stem cells and contribution to disease.

Epithelial branching during the process of lung development results in the establishment of distinct functional zones, each of which is characterized by a unique cellular composition and repertoire of local progenitor cells. Significant new insights into cellular and molecular mechanisms of epithelial maintenance that provide insights into the pathophysiology of lung disease have been made in recent years. This review focuses on the complex structure-function relationship in the airway epithelium, how this epithelium is maintained in the normal state and repaired following injury, and how deregulation may contribute to airway disease and cancer.

Effects of culturing on the population structure of a hyperthermophilic virus.

The existence of a culturing bias has long been known when sampling organisms from the environment. This bias underestimates microbial diversity and does not accurately reflect the most ecologically relevant species. Until now no study has examined the effects of culture bias on viral populations. We have employed culture-independent methods to assess the diversity of Sulfolobus spindle-shaped viruses (SSVs) from extremely hyperthermal environments. This diversity is then compared to the viral diversity of cultured samples. We detected a clear culturing bias between environmental samples and cultured isolates. This is the first study identifying a culture bias in a viral population.

Potential of solid phase extraction disks to aid determination of dislodgeable foliar residues of chlorpyriphos, malathion, diazinon, and acephate.

The utility of solid phase extraction (SPE) for concentrating four organophosphate insecticides from solutions of water and sodium dioctyl sulfosuccinate, a surfactant, was evaluated. Reverse phase (C18, octadecyl bonded silica) sorbent in the form of a disk was the SPE medium evaluated. Chlorpyriphos, malathion, and diazinon, but not acephate, were retained on and eluted from the SPE disks. For pesticides that were retained on SPE disks, recoveries from the disks were equal to or higher than recoveries achieved by solvent partitioning. Dislodgeable foliar residues of acephate were successfully concentrated for analysis by lyophilization of water-surfactant solutions. Recoveries of pesticides from SPE disks stored at -15 degrees C for one week were equal to or higher than those of pesticides stored in water-surfactant for one week at -15 degrees C. Malathion- and diazinon-fortified samples in watersurfactant and on SPE disks were prepared in one state and shipped for analysis in another state. Pesticides in the water-surfactant samples were concentrated by solvent partitioning and were underestimated by 41% (diazinon) and 16% (malathion). Conversely, diazinon samples on the SPE disks were on average underestimated by 3% and malathion was overestimated by an average of 55%. The overestimation of malathion was attributed to a matrix effect during analysis associated with the presence of surfactant, which was retained on and subsequently eluted from the SPE disks. The retention of surfactant by the SPE disks and its subsequent elution may considerably limit their usefulness in determination of dislodgeable foliar residues.

Sustainable soil management practices and quality of potato grown on erodible lands.

Land productivity can decline when top soil is lost. In Kentucky, limited resource farmers often produce vegetable crops on erodible lands. The objectives of this study were 1) to quantify the impact of three soil management practices (SMPs) on quantity of potato produced on erodible land, 2) to evaluate the impact of pyrethrin and azadirachtin insecticides on potato tuber quality, and 3) to assess the impact of yard waste compost on the chemical composition (ascorbic acid, free sugars, phenol contents) of potato tubers. Potatoes (Solanum tuberosum L. cv. Kennebec) were grown in a silty loam soil of 10% slope. Plots (n= 18) were 3.7 m wide and 22 m long (10% slope), with metal borders of 20 cm above ground level. Two botanical insecticides, Multi-Purpose Insecticide (containing pyrethrin 0.2%) and Neemix 4EC (containing 0.25% azadirachtin) were sprayed twice on potato foliage during each of two growing seasons (1997 and 1999) at the recommended rates of 6 lbs and 2 gallons.acre(-1), respectively. The SMPs were tall fescue strips (FS) intercropped between each two potato rows, soil mixed with yard waste compost (COM) and no-mulch (NM) treatment (roto-tilled bare soil). The experimental designwas a 2 x 3 x 3 factorial with main factors of two insecticides and three SMPs replicated three times. Average potato yield was lowest in NM and FS and highest in COM treatments. Yield obtained from the bottom of the plots was greater than that obtained from the top of plots. Tuber defects (rot, scab, sun green, hollow heart, necrosis, and vascular discoloration) were significantly different between the two growing seasons. The two insecticidal treatments did not have much influence on potato yield or tuber defects. Tubers obtained from tall fescue treatments had low levels of ascorbic acid and reducing sugars compared to compost treatments.

Pyrethrins and piperonyl butoxide residues on potato leaves and in soil under field conditions.

Residues of pyrethrin-I (Py-I) and pyrethrin-II (Py-II), the major insecticidal components of the pyrethrum daisy (Tanacetum cinerariifolium) as well as residues of piperonyl butoxide (PBO, a pyrethrum synergist) were determined in soil and on potato foliage grown under field conditions. A pyrethrum formulation (Multi-Purpose Insecticide) containing the three active ingredients was sprayed twice at the rate of 6 lbs of formulated product.acre(-1) ( 5.4 and 27.2 g A.I. of pyrethrin and PBO, respectively) on potato foliage during the growing season. In soil, three management practices (yard waste compost, grass filter strips, and a no mulch treatment) were used to study the impact of surface soil characteristics on the amount of pyrethrins (Pys) and PBO retained in soil. Soil samples and potato leaves were collected at different time intervals after spraying. Samples were purified and concentrated using solid-phase extraction columns containing C18-Octadecyl bonded silica. Residues were quantified by high-performance liquid chromatograph equipped with a UV detector. The first spray resulted in mean initial deposits of 0.18, 0.40, and 0.99 microg.g(-1) potato leaves for Py-I, Py-II, and PBO, respectively. Residues in soil were higher in compost treatments compared to no mulch treatments.

Repellency to two-spotted spider mite,Tetranychus urticae Koch, as related to leaf surface chemistry ofLycopersicon hirsutum accessions.

Bioassays employingTetranychus urticae Koch were used to examine repellency of leaves and trichome secretions of one cultivar of tomato,Lycopersicon esculentum, and 11 accessions ofL. hirsutum consisting of seven accessions ofL. hirsutum f.typicum and four accessions ofL. hirsutum f.glabratum. Leaves of f.typicum were more repellent to mites than were those of f.glabratum orL. esculentum. Removal of trichomes and their secretions by wiping leaves of f.typicum accessions with 95% ethanol rendered them less repellent, indicating that trichomes or their secretions were potentially responsible for repellency. Gas and thin-layer chromatography of leaflet washes obtained by steeping leaflets in hexane indicated that the chemical composition of the washes differed among accessions. The main difference between botanical forms was the presence in leaflet washes from f.typicum accessions of compounds eluting late on the gas Chromatograph and migrating further on reverse-phase thin-layer chromatography; compounds having these characteristics were absent in washes of f.glabratum andL. esculentum. The compositions of secretions taken directly from type I, type IV, and type VI trichomes were similar to that of the leaflet wash obtained from the same f.typicum plant, indicating that leaflet washes contained mainly compounds of trichomal origin. Leaflet washes from f.typicum plants were generally more repellent toT. urticae than were washes from f.glabratum when tested by choice and nonchoice bioassays. Taken together, the data indicate that trichome secretions of f.typicum are likely responsible for potent repellency to two-spotted spider mites observed in this taxon; the likely active compounds are sesquiterpene acids or other polar constituents of trichome secretions.

2,3-Dihydrofarnesoic acid, a unique terpene from trichomes ofLycopersicon hirsutum, repels spider mites.

Lycopersicon hirsutum, a wild relative of the tomato, is highly resistant to arthropod herbivores. Both botanic forms ofL. hirsutum, L. hirsutum f.glabratum (C.H. Mull.) andL. hirsutum f.typicum (Humb. & Bonpl.), are resistant to two-spotted spider mites,Tetranychus urticae Koch. However, leaves and trichome secretions from f.typicum repel mites more so than those from f.glabratum. We have previously demonstrated that trichome secretions from LA 1363 and LA 1927, accessions of f.typicum, repelled mites. In this paper we report the identification of the primary component of trichome secretions responsible for repellency. Leaflet washes having compositions similar to trichome secretions were collected and separated into neutral and acid fractions; repellency was mainly associated with the acid fraction, which, when applied to nonrepellent leaflets of f.glabratum, rendered them repellent. Separation of leaflet washes by HPLC allowed purification and subsequent identification by gas chromatography-mass spectrometry and nuclear magnetic resonance of 2,3-dihydrofamesoic acid (3,7,11-trimethyl-6, 10-dodecadienoic acid) as the primary chemical component responsible for repellency. Application of this acid to leaflets ofL. esculentum rendered them repellent. Other volatile compounds present in minor amounts in the acid fractions were farnesoic acid and 16∶0, 16∶3, 18∶0, 18∶2, and 18∶3 fatty acids. This is the first report of the natural occurrence of 2,3-dihydrofarnesoic acid.

Orthostatic hypotension: a potential side effect of psychiatric medications.

1. Orthostatic hypotension is a major underrecognized side effect of antipsychotic and antidepressant medications. It has been associated with falls, fractures, and lacerations, particularly in the elderly. 2. Orthostatic vital signs need to be routinely measured in patients susceptible to orthostasis. A standardized procedure should be available and must include a stable baseline measurement in the supine position at 30 seconds and 2 minutes in the sitting or standing position. 3. Measures to counteract orthostasis include nutrition/hydration assessment, environmental safety, and patient teaching.

When staff are assaulted. A nursing consultation support service.

Increasing patient to staff assaults led to the development of a Nursing Consultation Service, which can respond to the needs of assault victims and set the tone for institutional attitudes of nonblaming concern. A member of the consultation service meets with each known assault victim to review the incident, offer support, and provide assistance in addressing issues aroused by the incident. Implementation of this service and the use of a continuous monitor to track assault incidents is vital to highlight problem areas and develop assault prevention strategies.

Consensus and difference among hospital professionals in evaluating child maltreatment.

The decision-making process in suspected cases of child maltreatment involves reaching interprofessional consensus. Interprofessional consensus in seriousness ratings of maltreatment incidents for the welfare of the child was examined by surveying 39 case vignette ratings by 295 pediatric hospital professionals from five occupations. The survey instrument was derived from research by Giovannoni and Becerrra (1979). An exploratory factor analysis yielded five categories of maltreatment: physical abuse, sexual abuse, general failures in care, minor neglect/discipline, and lifestyles/values. A sixth category, parental sexual preference, was rated not very serious and did not appear to belong in the maltreatment domain. Nurses and social workers rated incidents as most serious, differing significantly from psychiatrists and, often, from physicians and psychologists. Professions agreed on rank ordering of categories by seriousness. Variables such as sex, parenthood status, years of experience, and medical specialty showed some relationship to ratings within some professional groups.

Rapid estimation of potato tuber total protein content with coomassie brilliant blue G-250.

A new method for measuring protein with Coo-massie Brilliant Blue G-250 has been adapted for use as a screening method in a potato tuber protein improvement breeding program. The method is simple, fast and inexpensive, and has successfully estimated the total protein content of a broad range of tuber genotypes having dissimilar amino acid profiles and tuber maturities. Correlation between the Coomassie method and a modified micro-Kjeldahl method, the standard method used in the potato breeding program, was 0.93. Free amino acids and other compounds which interfere with other methods for measuring protein do not interfere with the Coomassie Brilliant Blue procedure.