A leucine-rich repeat peptide derived from the Drosophila Toll receptor forms extended filaments with a beta-sheet structure.

Leucine-rich repeats (LRRs) are 22-28 amino acid-long sequence motifs found in a family of cytoplasmic, membrane and extracellular proteins. There is evidence that LRRs function in signal transduction, cellular adhesion and protein-protein interactions. Here we report unusual properties of a synthetic LRR peptide derived from the sequence of the Drosophila membrane receptor Toll. In neutral solution the peptide forms a gel revealed by electron microscopy to consist of extended filaments approximately 8 nm in thickness. As the gel forms, the circular dichroism spectrum of the peptide solution changes from one characteristic of random coil to one associated with beta-sheet structures. Molecular modelling suggests that the peptide form an amphipathic structure with a predominantly apolar and charged surface. Based on these results, models for the gross structure of the peptides filaments and a possible molecular mechanism for cellular adhesion are proposed.

A comparison of large-scale Sf9 insect cell growth and protein production: stirred vessel vs. airlift.

A simple and relatively inexpensive stirred-vessel system for the large-scale growth of insect cells (Sf9) is described. Sf9 cell growth in a stirred-vessel fermentor and an airlift fermentor were compared on the basis of maximum cell density and average population doubling time. Also, both fermentor systems were compared with respect to the large-scale production of a recombinant human protein (protein kinase C-eta). No significant differences in Sf9 cell growth or protein expression levels were apparent between the two fermentor systems. However, large differences in cost and scale-up of each system are discussed with respect to the large-scale production of recombinant proteins.

Octopamine-containing neurons in the alimentary tract of the earthworm (Eisenia fetida).

Octopamine-containing nerve cells have been demonstrated in the enteric plexus of the earthworm (Eisenia fetida), applying immunocytochemistry and HPLC assay. A few octopamine-immunoreactive neurons occurred in the fore- and hindgut, whereas their number in the midgut was considerably greater. Octopamine levels detected by HPLC correlated with the distribution of octopamine-containing nerve cells. A regulatory role for these intrinsic octopaminergic neurons is suggested in the enteric plexus in the earthworm alimentary tract. This is the first report on the occurrence of octopamine-containing nerve cells in the peripheral nervous system of an invertebrate.

Inhibition of neutrophil chemotaxis by protease inhibitors. Differential effect of inhibitors of serine and thiol proteases.

Previous studies have demonstrated that neutrophils possess an active serine protease(s) which may be involved in the process of chemotaxis but the precise identity of this enzyme(s) remains to be determined. In this study fourteen different protease inhibitors were tested over a wide concentration range for their ability to inhibit unstimulated neutrophil movement and chemotaxis to C5a, fMLP and IL-8. Pretreatment of neutrophils with aspartyl or metallo-protease inhibitors had no effect on either chemotaxis or random cell movement. The thiol protease inhibitors E-64 and cystatin, as well as the thiol/serine inhibitors antipain and leupeptin, diminished only C5a-induced chemotaxis. Pretreatment of neutrophils with the serine protease inhibitors PMSF or 3,4-DCI significantly reduced chemotaxis to C5a, fMLP and IL-8. The inhibitor of trypsin-like serine proteases, TLCK, and the neutrophil elastase inhibitor MeO-Suc-AAPV-CMK had no inhibitory effect on cell movement. However, two different inhibitors of chymotrypsin-like serine proteases, TPCK and chymostatin, significantly inhibited movement to any chemoattractant. These results suggest that an active chymotrypsin-like serine protease is essential for neutrophils to respond to chemotactic stimuli.

Structure and conformation of epimers derived from the antibiotic teicoplanin.

Basic hydrolyses carried out on the glycopeptide antibiotic teicoplanin or its acidic hydrolysis products give rise to epimeric species which retain little antibiotic activity. The detailed structure of a sample epimer has been determined using 1H NMR spectroscopy.

Life-threatening angioedema.

Angioedema is a well-recognized edema involving the deeper layers of the skin, subcutaneous tissue, and mucosa. From July 1986 to July 1989 the authors have observed and treated 10 patients admitted to the Medical College of Virginia (MCV) Hospitals in Richmond, Virginia, with life-threatening angioedema as a complication of enalapril or captopril ingestion. Both drugs are angiotensin-converting enzyme (ACE) inhibitors prescribed for antihypertensive activity and the ability to improve symptoms in patients with congestive heart failure. We describe the clinical symptoms, diagnosis, and management of these patients, as well as reasons for each occurrence. Sporadic reports of angioedema secondary to ACE inhibitor therapy have appeared in the literature. This represents the first time a significant series of patients from the same institution have encountered this complication over a short period of time, suggesting that the complication may be much more common than has been thought.

Unchanged intestinal absorption in rats fed a high sweet paprika-containing diet.

The absorption rate of radiolabelled nutrients (22Na, 45Ca, [35S]methionine, [3H]leucine) was investigated in vivo in Sprague-Dawley rats at the end of a feeding period of 135 days on a semisynthetic diet containing 32% sweet paprika powder. No effect was seen on the intestinal absorption of these compounds, nor on the nutritive experimental parameters in these animals.

Evaluation of testosterone response to intramuscular injection of GnRH and its correlation with sperm quality parameters in cockerels.

Eight 40-week-old New Hampshire cockerels (average liveweight: 3.10 +/- 0.2 kg) were used for studying the testosterone response to a single intramuscular dose (5 micrograms/kg b.w.) of exogenous 6D-Phe gonadotropin releasing hormone (GnRH). Serum samples were collected at 15-min intervals during the first hour and at half-hour intervals up to two hours post injection. The semen samples were collected 24 h before GnRH treatment. Testosterone peaks were found 45 to 60 min after the treatment. The coefficient of correlation between the semen quality parameters and the testosterone response to GnRH was evaluated both by Rank correlation and by multiple regression analyses. Rank correlation showed moderate but not significant values while multiple regression analyses showed a close correlation (multiple R = 0.72). The results show that testosterone response to GnRH may be used as a marker of semen quality in cockerels.

Motility and agglutination of fowl spermatozoa in media of different amino acid content and pH value in vitro.

The objective of the present experiments was to study some properties of fowl spermatozoa which may play a role in the sperm storage and emptying mechanism of the uterovaginal sperm storage tubules (SST) of the hen. The effects exerted by different amino acids (aspartic acid, Asp; glutamic acid, Glu; gamma-aminobutyric acid, GABA; glycine, Gly) and by the pH of the environment at 24 and 39 degrees C on the motility and agglutination of cock spermatozoa were studied in vitro. The spermatozoa did not show agglutination in the presence of Asp and Glu, and became immobilised if the concentration of Glu or the acidity of the environment was increased. In neutral solutions of GABA and Gly or in a faintly alkaline solution characteristic plait-like conglomerations could be seen. The motility of spermatozoa immobilised by Glu could be restored in a varying degree by the addition of GABA or Gly. At a temperature of 24 degrees C, the spermatozoa became immobilised in a medium of pH 6.0 while showed maximum motility at pH 7.1. At 39 degrees C, the spermatozoa were immobilised at higher pH (6.2) and required a pH value as high as 7.4-7.5 to show the highest motility. Spermatozoa inactivated in an acidic solution could be immediately mobilised by alkalisation of the medium, irrespective of the Ca2+ content of the solution. Thus, Ca2+ was not found to play a role in the reactivation of spermatozoa. Nevertheless, marked differences were observed in the maintenance of sperm motility between solutions either containing or lacking Ca2+. As the concentration changes of the above-mentioned amino acids and the pH changes were found to affect the motility and agglutination of spermatozoa in vitro, they may influence also the regulatory mechanism of the uterovaginal SST during the egg-formation cycle in vivo.

Amino acid secretion of the hen's oviduct during the egg formation cycle.

The free amino acid content of 34 hens' oviducts was determined in different phases of the egg formation cycle. In addition, quantitative changes of transmitter-type amino acids (glutamic acid, aspartic acid, taurine, glycine) were monitored in comparison with those of other amino acids participating in protein synthesis (e.g., lysine, tyrosine, valine). Different portions of the hen's oviduct, primarily the magnum and the uterus, were characterised by substantial amino acid secreting activity. The amino acids detectable in the highest quantity were taurine, glutamic acid, glycine and aspartic acid. These amino acids were present in high concentrations throughout the egg formation cycle, but their quantity abruptly decreased at the time of oviposition and ovulation. The quantitative changes of transmitter-type amino acids are mostly independent of those of other amino acids participating in protein synthesis. Since in our earlier in vitro studies the concentration changes of the transmitter amino acids studied were found to affect the motility and agglutination of spermatozoa, they--besides other factors--can be assumed to exert an influence on the sperm storage and release processes of the uterovaginal sperm storage tubules located in the oviduct of birds.

Reorganization of the GABAergic system following brain extirpation in the earthworm (Eisenia fetida, Annelida, Oligochaeta).

The reorganization of the GABAergic system was studied by means of immunohistochemistry after the symmetrical and asymmetrical (unilateral) extirpation of the brain of the annelid Eisenia fetida. GABA-immunoreactive neurons were first observed in the wound tissue on the 3rd postoperative day. Thereafter the number of labelled cells gradually increased, and by postoperative days 76-80 all GABA-immunoreactive cells (approx. 140 neurons) could be found in their final positions in the symmetrically regenerated brain. After asymmetrical brain extirpation, nearly all cells (70-75) could be detected in the regenerating hemisphere by postoperative days 50-56. In the early stages of the asymmetrical regeneration of the brain, more GABAergic cells were concentrated dorsally and laterally in the preganglion than during the symmetrical type of regeneration. In both types of regeneration, the immunoreactive neurons in the regenerated brain originated in part from undifferentiated neuroblasts situated in different parts of the body, and in part from dividing neurons localized mainly in the pharyngeal nerve plexus. Both exogenous GABA and picrotoxin, applied during the early stages (days 10- 12) of brain regeneration, inhibited the development of the wound tissue and the migration of the neuroblasts and the enteric neurons. At the same time, exogenous GABA application accelerated the proliferation of the pharyngeal neurons. No effect on the process of regeneration could be demonstrated when exogenous GABA and picrotoxin were given together.

The number of ganglion cells in the intact and regenerated nervous system in the earthworm (Lumbricus terrestris).

1. The nerve cell number is higher in the cerebral ganglion than in the subesophageal or segmental ganglia of Lumbricus terrestris. 2. The nerve cell number of the subesophageal ganglion is similar to that of the segmental ganglia in spite that the latter developed from a fusion of several ganglia. 3. Segmental ganglia in front and behind the clitellum can be considered as "typical" ganglia. 4. The most caudal segmental ganglia are less differentiated and resembles to the embryological state. 5. Nerve cells of the regenerating ganglia, at least in part, originate from undifferentiated nerve cells of the intact ganglia.

Distribution of Eisenia tetradecapeptide immunoreactive neurons in the nervous system of earthworms.

A detailed mapping of Eisenia-tetradecapeptide-immunoreactive neurons in the central and peripheral nervous system combined with quantitative morphological measurements was performed in Eisenia fetida and Lumbricus terrestris. In Eisenia, most labelled neurons were observed in the ganglia of the ventral cord (20.38% of the total cell number of the ganglion) and 15.67% immunoreactive cells occurred in the brain, while 6% of the neurons could be shown in the subesophageal ganglion. In the case of Lumbricus, most immunoreactive cells were found in the subesophageal ganglion (16.17%) and in the ventral ganglia (12.54%). The brain contained 122 ETP-immunoreactive cells (5.6%). The size of the immunoreactive cells varied between 35-75 microm. A small number of Eisenia-tetradecapeptide immunoreactive fibres were seen to leave the ventral ganglia via segmental nerves, and labelled processes could also be observed in the stomatogastric system and the body wall. Labelled axon branches originating from the segmental nerves formed an immunoreactive plexus both between the circular and longitudinal muscle layer and on the inner surface of the longitudinal muscle layer. This inner plexus was especially rich in the setal sac. Among the superficial epithelial cells the body wall contained a significant number of immunoreactive cells. Only a few Eisenia-tetradecapeptide immunoreactive neurons and fibres occurred in the stomatogastric ganglia. In the enteric plexus the number of immunoreactive neurons and fibres decreased along the cranio-caudal axis of the alimentary tract. Eisenia-tetradecapeptide immunoreactive cells were also present among the epithelial cells in the alimentary canal. Some of these cells resembled sensory neurons in the foregut, while others showed typical secretory cell morphology in the midgut and hindgut.

Reorganization of peptidergic systems during brain regeneration in Eisenia fetida (Oligochaeta, Annelida).

After the extirpation of the brain reorganization of the peptidergic (FMRFamide, neuropeptide Y, proctolin) systems was studied in the newly forming cerebral ganglion of the annelid Eisenia fetida. During regeneration, all immunoreactive fibres appear on the 1st-2nd postoperative day. At the beginning of regeneration, immunoreactive neurons and fibres form a mixed structure in the wound tissue. On the 3rd postoperative day, FMRFamide positive and neuropeptide Y-immunoreactive, while on the 7th postoperative day proctolin-immunoreactive neurons appear in the loose wound tissue. From the 25th postoperative day a capsule gradually develops around it. The neurons of the preganglion move to the surface of the newly appearing preganglion. The number of these cells gradually increase, and by the 72th-80th postoperative days the localization and number of peptide-immunoreactive neurons is similar to that in the intact one. The neurons of all examined peptidergic systems may originate from the neuroblasts, situated on the inner and outer surface of the intact ganglia (e.g. suboesophageal and ventral cord ganglia). In addition FMRFamide and proctolin immunoreactive neurons may take their derive by mitotic proliferation from the pharyngeal neurons, too.

[Roentgen diagnosis of congenital hip dysplasia]. / A veleszületett csípö-dysplasia röntgendiagnosztikája.

The X-ray of 4000 infants between the age of 4-6 months have been examined, regarding correlations between the measured Hilgenreiner's acetabular roof angle and the position of the pelvis during X-raying. Faulty positioning often was found, and only in 34,2% was the pelvis symmetric and the pelvic inclination normal, when the photos were made. The change of the acetabular roof angle due to the incorrect pelvic position is not always significant. The geometrical correction of these values is therefore not important and the other radiological signs of CDH can be relied on.