Identifications of two different mechanisms for sorghum midge resistance through QTL mapping.

Sorghum midge is the one of the most damaging insect pests of grain sorghum production worldwide. At least three different mechanisms are involved in midge resistance. The genetic bases of these mechanisms, however, are poorly understood.

Cholinergic modulation of memory in the basolateral amygdala involves activation of both m1 and m2 receptors.

Muscarinic cholinergic activation is a critical component of basolateral amygdala (BLA)-mediated modulation of memory consolidation. The receptor(s) mediating this activation during consolidation have not been elucidated. This study investigated the roles of muscarinic subtype 1 (m1) and subtype 2 (m2) receptors in memory enhancement, by post-training intra-BLA infusions of the non-selective muscarinic agonist oxotremorine.

Uncovering the mechanisms of deep brain stimulation for Parkinson's disease through functional imaging, neural recording, and neural modeling.

High-frequency deep brain stimulation (DBS) of the thalamus or basal ganglia represents an effective clinical technique for the treatment of several medically refractory movement disorders, including Parkinson's disease. However, understanding of the mechanisms of action of DBS remains elusive. The goal of this review is to address our understanding of the effects of high-frequency stimulation within the central nervous system based on results from functional imaging, neural recording, and neural modeling experiments.

Role of the basolateral amygdala in memory consolidation.

Memories of emotionally arousing events tend to be more vivid and to persist longer than do memories of neutral or trivial events. Moreover, memories of emotionally influenced information may endure after a single experience. Recent findings strongly suggest that the influence of emotional arousal on memory consolidation is mediated by the release of adrenal stress hormones (epinephrine and glucocorticoids) and neurotransmitters that converge in modulating the noradrenergic system within the amygdala.

Patterns of brain acetylcholine release predict individual differences in preferred learning strategies in rats.

Acetylcholine release was measured simultaneously in the hippocampus and dorsal striatum of rats before and during training on a maze that could be learned using either a hippocampus-dependent spatial strategy or a dorsal striatum-dependent turning strategy. A probe trial administered after rats reached a criterion of 9/10 correct responses revealed that about half of the rats used a spatial strategy and half a turning strategy to solve the task. Acetylcholine release in the hippocampus, as well as the ratio of acetylcholine release in the hippocampus vs.

Prediction of hybrid performance in grain sorghum using RFLP markers.

Heterosis is an important component of hybrid yield performance. Identifying high yielding hybrids is expensive and involves testing large numbers of hybrid combinations in multi-environment trials. Molecular marker diversity has been proposed as a more efficient method of selecting superior combinations.

Assessment of haemodialysis adequacy by ionic dialysance: intra-patient variability of delivered treatment.

Introduction: Adequate delivered dose of solute removal (as assessed by urea reduction and calculation of Kt/V) is an important determinant of clinical outcome in chronic haemodialysis (HD) patients. The requirement for multiple blood sampling and efforts taken to minimize the effects of rebound on post-treatment samples ensure Kt/V is measured only intermittently. On-line conductivity monitoring (using sodium flux as a surrogate for urea) allows the repeated non-invasive measurement of Kt/V on each HD treatment.

Amygdala modulation of memory consolidation: interaction with other brain systems.

There is a strong consensus that the amygdala is involved in mediating influences of emotional arousal and stress on learning and memory. There is extensive evidence that the basolateral amygdala (BLA) is a critical locus of integration of neuromodulatory influences regulating the consolidation of several forms of memory. Many drug and stress hormone influences converge in activating the release of norepinephrine (NE) within the BLA.

Long-term use of 1.1% amino acid dialysis solution in hypoalbuminemic continuous ambulatory peritoneal dialysis patients.

Introduction: Malnutrition is a common problem in patients treated with continuous ambulatory peritoneal dialysis (CAPD). Hypoalbuminemia in CAPD patients is an independent risk factor for death and is associated with malnutrition. Previous short-term studies have examined the use of amino acid based PD solutions in terms of albumin levels and anthropometric changes, but not clinical outcome.

Characterization of treatment dose delivered by albumin dialysis in the treatment of acute renal failure associated with severe hepatic dysfunction.

Background: Acute liver cell failure (ALCF) commonly results in death and when complicated by acute renal failure (ARF), the mortality approaches 90%. Albumin dialysis allows partial replacement of some of the liver's excretory functions. The molecular absorbents recirculating system (MARS) has been recently introduced to provide this therapy.

Amygdala norepinephrine levels after training predict inhibitory avoidance retention performance in rats.

Previous findings indicate that footshock and several drugs that modulate memory consolidation alter norepinephrine (noradrenaline) release in the amygdala, as assessed by in vivo microdialysis and high-performance liquid chromatography. Such findings suggest that norepinephrine release in the amygdala may be critical for regulating memory consolidation. The present study was the first to examine the relationship between norepinephrine release in the amygdala assessed after inhibitory avoidance training and 24-h retention performance within individual animals.

Extracellular stimulation of central neurons: influence of stimulus waveform and frequency on neuronal output.

The objective of this project was to examine the influence of stimulus waveform and frequency on extracellular stimulation of neurons with their cell bodies near the electrode (local cells) and fibers of passage in the CNS. Detailed computer-based models of CNS cells and axons were developed that accurately reproduced the dynamic firing properties of mammalian motoneurons including afterpotential shape, spike-frequency adaptation, and firing frequency as a function of stimulus amplitude. The neuron models were coupled to a three-dimensional finite element model of the spinal cord that solved for the potentials generated in the tissue medium by an extracellular electrode.

Identification of compound classes in soil and peat fulvic acids as observed by electrospray ionization tandem mass spectrometry.

Soil and peat fulvic acids obtained from the International Humic Substances Society were fractionated by their solubility in methanol and analyzed by electrospray ionization tandem mass spectrometry. Precursor and product ion experiments produced mass spectra that indicated the presence of benzene, phenol, dihydroxy benzene, furan and thiophene carboxylic acids. Standards were used to substantiate the fragmentation patterns observed in the product ion spectra of the fulvic acid samples.

A prospective study of combination therapy for hyperphosphataemia with calcium-containing phosphate binders and sevelamer in hypercalcaemic haemodialysis patients.

Introduction: Hyperphosphataemia is predictive of death, in haemodialysis (HD) patients. Sevelamer is a mineral-free phosphate binder not limited by the hypercalcaemia often encountered when utilizing calcium-containing phosphate binders. Highly positive calcium balance is associated with ectopic calcification and potentially accelerated vascular disease.

Gas jet as a waveguide for air-coupled ultrasound.

The directional characteristics of an ultrasonic signal have been studied during propagation within an axial gas jet. The effects of nozzle shape, nozzle diameter, and variations in jet velocity, temperature and gas composition have been investigated. At high flow velocities of an air jet, divergence of the ultrasonic beam was observed.

Simultaneous non-surgical removal and insertion of peritoneal dialysis catheters for defective drainage: a bedside, day case technique.

Background: Outflow failure of peritoneal dialysis catheters is a commonly encountered problem. It may be possible to reposition the catheter by a variety of means, but this can be problematical and has variable long-term success. Commonly surgical catheter exchange is utilized, entailing inconvenience, expense and often, a reliance on temporary hemodialysis.

Self-esterification of fulvic acid model compounds in methanolic solvents as observed by electrospray ionization mass spectrometry.

The self-esterification of two fulvic acid model compounds in methanolic solvents was studied by electrospray ionization mass spectrometry (ESI-MS). The strongly acidic tetrahydrofurantetracarboxylic acid rapidly self-esterified to form mono- and dimethyl esters when stored in methanol, even at reduced temperatures. The weakly acidic analogue, cyclopentanetetracarboxylic acid, reacted minimally under the same conditions.

Pyridazine based inhibitors of p38 MAPK.

Trisubstituted pyridazines were synthesized and evaluated as in vitro inhibitors of p38MAPK. The most active isomers were those possessing an aryl group alpha and a heteroaryl group beta relative to the nitrogen atom in the 2-position of the central pyridazine. Additionally, substitution in the 6-position of the central pyridazine with a variety of dialkylamino substituents afforded a set of inhibitors having good (p38 IC50 1-20 nM) in vitro activity.