Egg dispersion in codling moth: Influence of egg extract and of its fatty acid constituents

Codling moth females (Cydia pomonella, Lepidoptera: Tortricidae) (CM) usually lay single eggs and have a tendency to disperse. In a first experiment we observed that single females exposed to 20 apples distribute their eggs regularly among apples, suggesting a dispersive oviposition behavior. In a dual-choice situation, isolated females avoided oviposition on areas of cardboard treated with a methylene dichloride egg extract at the dose of ca. 1.0 egg equivalent/cm². A strong avoidance was obtained in response to a 20-fold dose, which was accompanied by a significant reduction of total oviposition. Seven major compounds found by GC analyses in the methylene dichloride extract of 2 to 3-day-old eggs were saturated or unsaturated C₁₄-C₁₈ straight-chain fatty acids: myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid. This was confirmed by GC-MS analysis of an extract made by ethyl ether. Smaller amounts of three methyl esters were also identified as methyl myristate, methyl palmitate, and methyl stearate. A blend of the seven fatty acids (FA) mimicked rather well the avoidance provoked by the extract, and this avoidance was confirmed by choice between treated and untreated fruits by single females. The treatment of apples with the 7FA mixture induced an aggregative distribution of the eggs among apples. We also found that the amounts of fatty acids harvested in the extract depend on the egg age. Amounts of fatty acids increased until eggs were 4 days old and then decreased before hatching. In this paper we discuss the possible role of simple molecules, such as fatty acids and their esters, as semiochemicals indicative of juvenile tissues.     

Gymnastic wrist injuries

The evolution of enteral feeding via tubes, syringes, and other mechanical devices probably began in Egypt before the birth of Christ. Today's feeding tubes are a safe and effective means for providing long-term feeding to patients unable to maintain sufficient nutrition by oral intake. The needs of enterally-fed patients are presently being met with feeding tubes that are biocompatible, easy to use, and relatively inexpensive to manufacture.     

Effects of angiotensin II generated by an angiotensin converting enzyme-independent pathway on left ventricular performance in the conscious baboon

Human chymase is a serine proteinase that converts angiotensin (Ang) I to Ang II independent of angiotensin converting enzyme (ACE) in vitro. The effects of chymase on systemic hemodynamics and left ventricular function in vivo were studied in nine conscious baboons instrumented with a LV micromanometer and LV minor axis and wall thickness sonomicrometer crystal pairs. Measurements were made at baseline and after [Pro11DAla12] Ang I, a specific substrate for human chymase, was given in consecutive fashion as a 0.1 mg bolus, an hour-long intravenous infusion of 5 mg, a 3 mg bolus, and after 5 mg of an Ang II receptor antagonist. [Pro11DAla12]Ang I significantly increased LV systolic and diastolic pressure, LV end-diastolic and end systolic dimensions and the time constant of LV relaxation and significantly decreased LV fractional shortening and wall thickening. Administration of a specific Ang II receptor antagonist reversed all the hemodynamic changes. In separate studies, similar results were obtained in six of the baboons with ACE blockade (20 mg, intravenous captopril). Post-mortem studies indicated that chymase-like activity was widely distributed in multiple tissues. Thus, in primates, Ang I is converted into Ang II by an enzyme with chymase-like activity. This study provides the first in vivo evidence of an ACE-independent pathway for Ang II production.     

In vivo pharmacology of an angiotensin AT1 receptor antagonist with balanced affinity for AT2 receptors

L-163,017 (6-[benzoylamino]-7-methyl-2-propyl-3-[[2'-(N-(3-methyl-1-butoxy) carbonylaminosulfonyl)[1,1']-biphenyl-4-yl]methyl]-3H-imidazo[4,5- b]pyridine) is a potent, orally active, nonpeptide angiotensin II receptor antagonist. Conscious rats and dogs were dosed p.o. and i.v.; in both species the plasma bioequivalents are similar at the angiotensin AT1 and AT2 receptor sites indicating balanced activity is maintained in vivo. L-163,017 prevents the pressor response to intravenous (i.v.) angiotensin II in the conscious rat, dog, and rhesus monkey. L-163,017 also significantly reduces blood pressure in a renin-dependent model of hypertension, similar to an angiotensin converting enzyme inhibitor (Enalapril) and an angiotensin AT1 receptor-selective antagonist (L-159,282). These studies indicate that neither the angiotensin AT2 receptor nor bradykinin is important in the acute antihypertensive activity of angiotensin converting enzyme inhibitors or angiotensin II receptor antagonists.     

Health benefits for the terminally ill: reality and perception

This paper examines the availability and scope of hospice benefits as well as employers' attitudes and knowledge about care for the terminally ill. Data are drawn from a national random sample of 1,502 employers with 200 or more workers and from focus groups with employee benefits managers and their insurance advisers, brokers, and consultants. Major findings are that 83 percent of employers offer explicit hospice benefits, with most other firms covering hospice through high-cost case management. Most employers support the concept of hospice care because they believe that it reduces medical expenses.     

Family variables in substance-misusing male adolescents: the importance of maternal disorder

Production of hydrogen by anaerobes, facultative anaerobes, aerobes, methylotrophs, and photosynthetic bacteria is possible. Anaerobic Clostridia are potential producers and immobilized C. butyricum produces 2 mol H2/mol glucose at 50% efficiency. Spontaneous production of H2 from formate and glucose by immobilized Escherichia coli showed 100% and 60% efficiencies, respectively. Enterobactericiae produces H2 at similar efficiency from different monosaccharides during growth. Among methylotrophs, methanogenes, rumen bacteria, and thermophilic archae, Ruminococcus albus, is promising (2.37 mol/mol glucose). Immobilized aerobic Bacillus licheniformis optimally produces 0.7 mol H2/mol glucose. Photosynthetic Rhodospirillum rubrum produces 4, 7, and 6 mol of H2 from acetate, succinate, and malate, respectively. Excellent productivity (6.2 mol H2/mol glucose) by co-cultures of Cellulomonas with a hydrogenase uptake (Hup) mutant of R. capsulata on cellulose was found. Cyanobacteria, viz., Anabaena, Synechococcus, and Oscillatoria sp., have been studied for photoproduction of H2. Immobilized A. cylindrica produces H2 (20 ml/g dry wt/h) continually for 1 year. Increased H2 productivity was found for Hup mutant of A. variabilis. Synechococcus sp. has a high potential for H2 production in fermentors and outdoor cultures. Simultaneous productions of oxychemicals and H2 by Klebseilla sp. and by enzymatic methods were also attempted. The fate of H2 biotechnology is presumed to be dictated by the stock of fossil fuel and state of pollution in future.     

Uptake of seven myocardial tracers during increased myocardial blood flow by dobutamine infusion

RATIONALE AND OBJECTIVES: Direct comparison of myocardial perfusion tracers has been made difficult by variability in experimental models, and by a virtual absence of data comparing tracer uptake to myocardial blood flow under conditions of increased myocardial oxygen consumption, similar to what occurs with dynamic exercise. METHODS: Tracer uptake versus myocardial blood flow was evaluated for thallium-201 (201TI) and six technetium-99m (99mTc) myocardial-imaging agents in 24 open-chest canines with an occluded left-anterior descending coronary artery during dobutamine infusion. Data were fitted to the exponential model y = ax(1 - exp[-PSc/x]), where y is the tissue tracer/g normalized to normal (activity at 1 mL/minute/g) and x is the blood flow measured by the radioactive microsphere method. RESULTS: With dobutamine, myocardial tracer uptake was linear across a wide range of ischemic and hyperemic flows for each tracer. Based on the permeability surface area product, 201TI and 99mTc Q3 provided the best tracer estimate of myocardial blood flow (5.30+/-0.86 mL/minute/g, r = 0.91; 5.46+/-0.58 mL/minute/g, r = 0.94, respectively). Correlation coefficient (r) values for other tracers studied were 99mTc Q4 (r =0.93), 99mTc Q12 (r = 0.93), 99mTc sestamibi (r = 0.90), 99mTc tetrofosmin (r = 0.96), and 99mTc-N-Noet (r = 0.82). CONCLUSIONS: Of the 99mTc tracers examined under conditions of dobutamine-altered myocardial contractility, the myocardial uptake properties of 99mTc Q3 were most similar to those of 201TI.     

Instability of primary dendrite arms in columnar Chernov crystals

Some features of dendrite coarsening are studied on individual columnar dendrites in a large steel ingot. The coarsening of dendrite arms in Chernov columnar crystals is observed only in the zone of conventional solidification. In the tips of crystals that penetrate into the shrinkage cavity of the ingot, the initial sizes of the dendrite arms do not change. The coarsening of the primary arms is shown to cause crystal fragmentation into individual dendrites.