Multiple forms of amylase in leaf extracts: electrophoretic transfer of the enzyme forms into amylose-containing polyacrylamide gels

A method for the analysis of multiple forms of glucan-degrading enzymes is described. The procedure consists of the separation of the proteins by electrophoresis or isoelectric focusing in glucan-free polyacrylamide gels followed by the nondenaturing electrophoretic transfer into a second polyacrylamide layer which contains immobilized glucans. The method combines the resolving power of electrophoretic separations in glucan-free media with the sensitivity of amylase activity detection in amylose-containing polyacrylamide gels. The procedure is especially useful when samples containing low amylase activity, but a large number of multiple enzyme forms, are to be analyzed.     

Application of the imidate procedure to α-d-galactosyltion

Using the imidate procedure, 2,3,4,6-tetra-O-benzyl-1-O-(N-methylacetimidoyl)-β-d-galactopyranose was condensed with various monosaccharides to provide, in good yield and with high stereoselectivity, α-linked disaccharides.     

Block by phencyclidine of acetylcholine and barium induced adrenal catecholamine secretion

Activation of the sympathetic system by phencyclidine (PCP) should result in catecholamine release from the adrenals. However, adrenalectomy does not reduce PCP-induced hypertension. In an attempt to rectify this inconsistency, the direct effects of PCP on the bovine adrenal medulla were examined. At (3×10^?6M), PCP reduced the acetylcholine-(ACh)-induced catecholamine release by 50%. Surprisingly, barium-induced secretion of catecholamines was also reduced by PCP. ACh-induced catecholamine release was not altered by 10^?3M 4-aminopyridine (4 AP), the potassium channel blocker. Thus, calcium antagonist actions of PCP and consequent block of catecholamine secretion from adrenal medulla may explain the lack of effect of adrenalectomy on PCP-induced hypertension. Possible contributions of calcium and/or potassium channel blockade to other manifestations of PCP overdosage are discussed.     

Influence of increasing levels of β-glucanase on the productive value of barley diets for broiler chickens

The influence on the productive value of diets for broiler chickens based on barley harvested at two stages of ripeness, when including β-glucanase in increasing amounts, was evaluated in a production experiment over three weeks. Feed consumption and live weight increased (P < 0.001) and feed conversion was improved (P < 0.001) by including β-glucanase in the diets. Dry matter content of excreta increased significantly as a result of β-glucanase inclusion. Broiler chickens receiving diets based on barley harvested at combine ripeness were slightly heavier (P < 0.05) at three weeks than those fed on barley harvested at early yellow ripeness.     

Single-step,rapid separation of acidic and basic isoenzymes from commercial horseradish peroxidase

A simple and sensitive high-performance liquid chromatography method with electrochemical detector is described for the determination of free 3-methoxy-4-hydroxyphenylacetic acid (HVA) in human plasma. The method does not involve any extraction, is specific and reproducible, and has the potential to measure serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) simultaneously. The plasma concentration of free HVA in eight normal, healthy adult volunteers was 10.9 ± 4.6 (mean ± SD). In a preliminary study, in one schizophrenic patient the plasma HVA increased twofold after neuroleptic treatment.     

Neuron differentiation and axon growth in the developing wing of Drosophila melanogaster

Sensory neurons in the wing of Drosophila originate locally from epithelial cells and send their axons toward the base of the wing in two major bundles, the L1 and L3 nerves. We have estimated the birth times of a number of identified wing sensory neurons using an X-irradiation technique and have followed the appearance of their somata and axons by means of an immunohistochemical stain. These cells become immunoreactive and begin axon growth in a sequence which mirrors the sequence of their birth times. The earliest ones are born before pupariation and begin axonogenesis within 1 to 2 hr after the onset of metamorphosis; the last are born and differentiate some 12 to 14 hr later. The L1 and L3 nerves are formed in sections, with specific neurons pioneering defined stretches of the pathways during the period between 0 and 4 hr after pupariation (AP), and finally joining together around 12 hr AP. By 16 hr AP the adult complement of neurons is present and the adult peripheral nerve pattern has been established. Pathway establishment appears to be specified by multiple cues. In places where neurons differentiate in close proximity to one another, random filopodial exploration followed by axon growth to a neighboring neuron soma might be the major factor leading to pathway construction. In other locations, filopodial contact between neighboring somata does not appear to occur, and axon pathways joining neural neighbors by the most direct route are not established. We propose that in these cases additional factors, including veins which are already present at the time of axonogenesis, influence the growth of axons through non-neural tissues.     

Ordination and classification of operational geographic units in Southwest Sweden

The vascular plant distributions of Dalsland and northern Bohuslän (Southwest Sweden) were subjected to multivariate analyses in order to delimit geographically coherent floristic zones. 271 squares of 5×5 km were the Operational Geographic Units; the data matrix comprises presence/absence species records for each OGU. Different ordination and classification methods were tested and detailed results are presented for detrended correspondence analysis (DCA), UPGMA and ordination space partitioning (OSP). A weighting procedure, neighbour-weighting, which gives pseudo-frequency scores along the nominal scale 0–9 depending on the species' distribution patterns, is introduced. The superior method for delimiting geographically coherent floristic zones was judged to be ordination space partitioning, using DCA and neighbour-weighted species scores.Abbreviations DCA Detrended Correspondence Analysis - OGU Operational Geographical Unit - OSP Ordination Space Partitioning - UPGMA Unweighted Pair-Group Method using Arithmetic Averages     

Plasma catecholamines: effects of footshock level and hormonal modulators of memory storage

Plasma levels of norepinephrine (NE) and epinephrine (EPI) were measured in male Sprague-Dawley rats before and at several times after training injections of agents known to enhance or to impair later retention performance for a one-trial inhibitory (passive) avoidance task. Two days before testing, each animal was surgically prepared with a chronic tail artery catheter that allows for repeated blood sampling in unhandled rats. Exposure to a single, intense training footshock (3.0 mA, 2.0 sec duration) resulted in an immediate but transient increase in plasma levels of EPI and to a lesser extent NE. Plasma levels of both catecholamines did not differ between unshocked controls and animals that received a weak training footshock (0.6 mA, 0.5 sec duration). An injection of EPI at a dose that enhances retention performance (0.1 mg/kg, sc) resulted in increments in plasma EPI levels of 0.8-1.9 ng/ml from 5 to 40 min after injection. An injection of EPI (0.5 mg/kg, sc) at a dose that produces retrograde amnesia resulted in increments in plasma EPI ranging from 3.7 to 4.5 ng/ml during the 40 min after injection. Plasma NE levels were not significantly altered following an EPI injection. A single injection of adrenocorticotropin (ACTH, 0.3 or 3.0 IU per rat) did not alter the plasma catecholamine responses to training with a weak footshock. Similarly, the synthetic ACTH analog, Organon 2766 (125 or 250 mg/Kg) did not affect plasma catecholamines in untrained (unshocked) rats.These results demonstrate that significant increments in plasma levels of NE and EPI occur shortly after inhibitory avoidance training. Furthermore, an injection of EPI that enhances retention of an inhibitory avoidance task mimics the magnitude, though not the temporal characteristics, of the endogenous adrenal medullary response to a training footshock. Other hormonal treatments (ACTH and Organon 2766) which enhance memory storage do not affect plasma levels of NE and EPI.