Fatty acids stimulate trehalose synthesis in trophocytes of the cockroach (Periplaneta americana) fat body

Trophocytes from the disaggregated fat body of the cockroach (Periplaneta americana) respond to synthetic hypertrehalosemic hormone (HTH) by increasing the rate of trehalose synthesis. The cells give a similar response when incubated with stearic, oleic, linoleic, or arachidonic acid. A maximal increase in trehalose synthesis was obtained with 1-10 microM fatty acids. Synthesis of trehalose by the trophocytes was also increased by 1 microM prostaglandin F2alpha to nearly the same extent as that evoked by HTH. Furthermore, the data show that the trophocytes are capable of converting linoleic acid into arachidonic acid. This suggests that the cells may convert arachidonic acid, formed from the linoleic acid released by the action of HTH, to a prostaglandin which serves as an integral part of the hypertrehalosemic mechanism.     

Fine structure of the first optic ganglion (lamina) of the cockroach, Periplaneta americana

The stuctural organization of the first optic ganglion (lamina) of the cockroach (Periplaneta americana) was investigated by the use of light and electron microscopy. Each compound eye of the cockroach is composed of up to 2000 visual units (ommatidia) of the fused rhabdom type. The ommatidia themselves consist of eight receptor cells which terminate as axons in either the first or second optic ganglion. Three different short visual fibre types end in two separate strata in the lamina, and one long fibre type ends in the second optic ganglion. Monopolar second-order neurons with wide field branching patterns in the middle stratum of the first synaptic region have postsynaptic contacts with sort visual fibres. Horizontal fibre elements with branching patterns at different levels of the lamina apparently from three horizontal plexuses with presynaptic and/or postsynaptic connections to first-and second-order neurons. The lack of well-organized fibre cartridges containing a constant number of first and second order neurons in each fascicle and the presence of only unistratified wide field monopolar cells could represent, as compared to other insect orders, a primitive stage in the development of the first optic ganglion.     

Stress-induced release of octopamine in the American cockroach Periplaneta americana L

The level of arachidonic acid (AA) metabolites in the supernatants of cultured peritoneal exudate cells (PEC) were studied under various conditions using BCG and Corynebacterium parvum as stimulators. The metabolite levels were analyzed by thin layer chromatography (TLC). The degree of macrophage cytotoxic/cytostatic activity was dependent on the dose and character of stimulators used and the source of macrophages. The application of microcytotoxicity assay for the evaluation of tumor cell lysis (lung sarcoma SaL-1) in vitro revealed that peritoneal macrophages from healthy and tumor bearing BALB/c mice may affect the degree of antitumor response. In the supernatants of cultured PEC from tumor bearing mice AA level increased (by 10-fold) in comparison with PEC from healthy mice. Stimulation with BCG induced over a double level of AA in PEC isolated from tumor bearing mice nonstimulated or stimulated with C. parvum. A lower level of prostaglandins (PGs) was found in the supernatants of cultured PEC isolated from healthy mice (stimulated and non-stimulated), but the highest level of PGs was observed in the supernatants of cultured PEC isolated from tumor bearing mice stimulated with BCG. The unique metabolite of AA was found only in the supernatants from nonstimulated PEC from tumor bearing mice. PEC from tumor bearing mice produced metabolites of AA which were not detected in control group. These results suggest that macrophages also play a regulatory role by secretion of AA. This process can be modified by bacterial antigens.     

Isolation of a novel RFamide peptide from the midgut of the American cockroach, Periplaneta americana

In insects (FM)RFamide-immunoreactive endocrine cells are ubiquitously present in the midgut, but the identity of the peptide(s) produced by these cells is unknown. The major RFamide-immunoreactive peptide from the midgut of the American cockroach, Periplaneta americana, was isolated and identified as Ala-Asn-Arg-Ser-Leu-Arg-Leu-Arg-Pheamide. This is a novel member of an arthropod peptide family, previously known only from mosquitoes and horseshoe crabs. Its abundance in the midgut suggests that it plays an important function in digestion.     

Incubation effect in the cockroach (Periplaneta Americana).

Recorded in Exp I the activity of 72 cockroaches in an open field in which they had received footshock (FS) 1, 3, 10, 30, or 120 min before. The FS produced an incubation effect, i.e., a general decrease in activity, with the greatest decrease occurring at the longer intervals. In Exp II, activity of 77 cockroaches was recorded in an open field 120 min after 1 FS and 1, 3, 10, or 30 min after a 2nd. When no 2nd FS was administered, the cockroaches were inactive; however, when testing occurred within 10 min of the 2nd FS, activity was greatly increased. This gradient of hyperactivity paralleled exactly the incubation effect demonstrated in Exp I. Results of both experiments are almost identical to the results of comparable experiments in which rats have served as Ss. Thus, the incubation effect is an adaptive behavior pattern resulting from the transient activating effects of noxious stimulation. (29 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Locations and central projections of neurons associated with the retrocerebral neuroendocrine complex of the cockroach Periplaneta americana (L.)

Retrograde diffusion and precipitation of Co2+ reveals in the ipsilateral pars lateralis (PL) and contralateral pars intercerebralis (PI) of the brain neurons that enter the corpus cardiacum (CC), and, possibly, the corpus allatum (CA) on each side. The PL group consists of 29.6 +/- 8.4 somata that fill. Of these, 5.6 +/- 0.6 exceed 25 micrometer in diameter, 14.3 +/- 2.7 range from 15--25 micrometer, and 9.6 +/- 7.6 are smaller than 15 micrometer. After CoCl2 was applied to the right CC-CA of two males, 239 and 265 somata in the left PI stained. Except for 16 ranging from 30--45 micrometers and chiefly located anteriorly, a majority of these somata measured 10--25 micrometer. The only somata revealed by staining whole brains with the performic acid-resorcin fuchsin method are neurosecretory cells 10--20 micrometer in diameter located within the PI. In starved adult males there are 92.4 +/- 8.1 on the right, and 93.2 +/- 6.9 on the left. The largest somata in the PL group contain numerous granules that stain with paraldehyde fuchsin. These somata also fill with Co2+, and belong to neurosecretory cells that extend into the CC-CA. The cerebral distribution of branches from the PL group, and the relationship of these to the corpora pedunculata, central body, and arborizations from the PI decussation are described.     

Influence of the subesophageal ganglion on the electrical activity of neurons of the metathoracic ganglion of the cockroach Periplaneta americana

Studies have been made of non-specific effect of suboesophageal gnaglion on excitability of the segmental centers in the cockroach P. americana. It was shown that the electrical stimulation of the ganglion increases the frequency of the spontaneous activity and decreases the threshold of the evoked reactions in neurons of the metathoracic ganglion. The level of activation depends on the intensity of stimulation. Application of GABA (0.1 M) to the suboesophageal ganglion decreases the frequency of the background activity in the segmental neurons, this effect being presumably due to activation of the inhibitory structures. The descending influences from the suboesophageal ganglion may spread to centers of the metathoracic ganglion along monosynaptic pathways.     

The influence of reinforcement and punishment in a minimal social situation.

"Two Ss, isolated from each other, were provided with two push buttons by means of which each could give the other a shock or score. The Ss were divided into a Weak Shock and a Strong Shock group. All Ss were merely told that they could press the two buttons in any manner that they pleased (no information was given concerning the purpose of the buttons). Each S was told to make as many points as possible. His score was indicated on a counter in front of S. It was found that the proportion of the total number of responses (both score and shock) that were correct (score responses) was significantly higher for the Strong Shock group. Learning occurred in the Strong Shock group within the first 5 minutes of the 25 minute experimental session. Learning was not, however, evident in the Weak Shock group." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of intermittent and constant punishment on resistance to punishment in a free operant situation for the albino rat.

Trained male Wistar albino rats (10 experimental and 9 control Ss) to barpress for food reinforcement in a 2-bar cyclic response chain situation. Responding on 1 bar led also to a punishment (footshock) on either an intermittent or constant schedule. Both punishment schedules led to increased responding on the nonpunished bar and to initial response suppression followed by recovery on the punished bar. For Ss on the intermittent schedule, the response increase on the nonpunished bar was seen only after a punishment on the other bar. Similar effects were found for transfer time between the 2 bars. The effects of punishment on response to both bars were more pronounced for the intermittent punishment groups. Results are discussed in terms of the motivational constructs of A. Amsel and of R. K. Banks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of diflubenzuron on the incorporation of UDP-N-acetyl-[3H]glucosamine (UDP-[3H]NAGA) to chitin in permeabilized, and isolated integuments from the newly molted American cockroach Periplaneta americana

1. Diflubenzuron (DFB) was found to inhibit the incorporation of UDP-N-acetyl-[3H]glucosamine (UDP-[3H]NAGA) to chitin in permeabilized and isolated integument from newly molted American cockroach. 2. The favorable experimental conditions demonstrating the effect of diflubenzuron were: 10 mM phosphate, low calcium concentration (10(-6) M-10(-8) M), high potassium concentration (> 100 mM), and high pH (> or = 7). 3. The action of diflubenzuron was completely erased by preincubating the isolated integument with valinomycin, FCCP, or A23187. 4. By lowering the external pH to 5.2, it was also possible to reduce the rate of UDP-[3H]NAGA incorporation to the extent that DFB's effect was no longer recognizable. 5. Both Cs+ and Rb+ could replace K+ in maintaining a high level of chitin synthesis and the inhibitory action of DFB under the optimum conditions.     

Quantitative structure-activity studies of octopaminergic 2-(arylimino)thiazolidines and oxazolidines against the nervous system of Periplaneta americana L

The quantitative structure-activity relationship (QSAR) of octopaminergic 2-(arylimino)thiazolidines (AITs) and 2-(arylimino)oxazolidines (AIOs) against the thoracic nerve cord of the American cockroach, Periplaneta americana L., was analysed using reported physicochemical parameters and regression analysis. The more electron-donating, the less bulky at m-position, and the more hydrophobic the substituent, the greater the activity. The plots of observed log Vmax values against calculated log Vmax values having substituents on the m-position deviated downwards from those of compounds having substituents at the 0- and/or p-positions. The more hydrophobic and the more electron-withdrawing the substituent, the greater the activity. AIO with a 2, 3, 4-trichlorophenyl group (58) was more active than its thiazolidine derivative, 2-(2,3,4-trichlorophenylimino)thiazolidine (38) in terms of Vmax:Vmax of 58 was 30% relative to octopamine (OA), whereas that of 38 has been 9% relative to OA, respectively. Superimposition of energy-minimized OA and 58 revealed structural and conformational similarities that might account for the high activity of 58.     

The role of social experience in the production of gastric ulcers in hooded rats placed in a conflict situation.

40 male hooded rats were used in an investigation concerning the relation of social experience to ulcer formation in a long-term approach-avoidance conflict situation. The hypotheses were: "1. Animals placed in the conflict situation alone are less resistant to ulceration than animals tested with other animals present. 2. Animals reared in isolation are less resistant to ulceration than animals reared together. 3. Interaction effects between these 2 sets of conditions exist." The first hypothesis was confirmed at the .01 level; the second and third hypotheses were not confirmed, probably owing to the limitations in the sensitivity of the experimental procedures. 21 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Vicarious punishment in a work setting.

Investigated the effects of punishment on the attitudes and behavior of co-workers (CWs) who observed a peer receiving punishment to test the hypothesis that observing a CW receive punishment will have a positive effect on observers' productivity without damaging job satisfaction. 60 students were hired through a university placement office for temporary clerical employment. Ss were exposed to observing either a CW receiving a reduction in pay or a threat of a reduction in pay or to no punishment (controls). Results support the hypothesis that punishment may be used effectively in work settings: Ss who observed a CW receiving a reduction in pay produced significantly more than controls and Ss who observed a threat of a reduction in pay. These effects did not diminish after 1 wk, and Ss across groups did not differ in levels of job satisfaction. Because none of the Ss knew each other, it is suggested that the absence of negative side effects may not have held if CWs had observed someone they knew receiving punishment. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of punishment (electric shock) on perceptual learning.

3 experiments were conducted to explore the consequences of the association of punishment with percepts and to trace its residual effects. Electric shock was associated with tactual profiles of faces. Voltage, temporal contiguity, and ability to escape shock were varied. The results showed that there was more reporting of the non-shocked profile as intensity of shock increased, that escape conditions lead to more reporting of the shocked profiles, the shocked profile is recalled more vividly, and as the delay between exposure and recall increases there is more reporting of the nonshocked profile. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Crime and punishment in the Army.

The relationship between crime and punishment is examined, and a dilemma in this relationship is identified. Labeling theory suggests that leaders responsible for enforcing the law respond to the crime they see by increasing punishment, under the assumption that punishment will deter crime, whereas recipients often respond to this punishment with a feeling of injustice, which then incites them to break the law more frequently, resulting in more serious problems on a delayed basis. The operation of this sort of dilemma in a US Army population was tested with cross-lagged panel correlation, using companies (groups of about 200 soldiers) as the unit of analysis. In 50 companies, company leaders punished their subordinates, particularly Blacks, as a response to the lawlessness they attributed to these subordinates, while subordinates responded to this punishment in the ensuing months with a sense of injustice and increased lawlessness. Observations are offered about the usefulness of the methodology and about the implications of the dilemma that has been identified for law-abidingness. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Identification of the swine pathogen Serpulina hyodysenteriae in rheas (Rhea americana)

Recently intestinal spirochetes were isolated from rheas in Ohio and Iowa with a necrotizing typhlocolitis. These intestinal spirochetes, strains R1 and NIV-1, were characterized and compared with other intestinal spirochetes, including strains of S. hyodysenteriae. Both rhea spirochetes were indole positive, strongly beta-hemolytic, grew under a 1% O2:99% N2 atmosphere, and were morphologically similar to spirochetes in the genus Serpulina. Analysis of rRNA gene restriction patterns (ribotypes), and immunoblots of whole cell proteins, indicated both spirochetes were similar to Serpulina hyodysenteriae strains from swine. Comparisons of nearly complete sequences (> 1458 bases) of the 16S rRNA gene of the two rhea spirochetes with S. hyodysenteriae strains confirmed that rhea spirochetes R1 and NIV-1 were strains of S. hyodysenteriae. These results indicate that S. hyodysenteriae has a broader host range than previously recognized.     

Pulmonary atresia with intact i.v. septum (author''s transl)

Eight cases of pulmonary atresia with intact ventricular septum, are reviewed. Three corresponded to the group with small or hypoplastic right ventricle and five to the one with normal or enlarged right ventricular cavity. The electrocardiogram was of less value than plain chest radiography for the differential diagnosis of both groups. Cardiac catheterization revealed a right to left atrial shunt and the suprasystemic level of the right ventricular pressure. Selective angiocardiography demonstrates the stop of contrast at the level of pulmonary valve. Five patients were operated. An ascending aorta to right pulmonary artery anastomosis, Waterston type, was performed in three patients. Pulmonary valvotomy was carried out in the others.