| t cell epitope specificity in human allergic and nonallergic subjects to bee venom phospholipase a2. | phospholipase a2 (pla) is a biochemically fully defined glycoprotein, representing the main allergen of bee venom. we have established cd4+ t cell clones specific to pla from subjects allergic and nonallergic to bee sting. by screening the epitope specificity of these clones with 62 synthetic overlapping dodecapeptides representing the pla molecule, two immunogenic epitopes, pla81-92 and pla113-124, were identified. additional screening, using longer peptides of up to 18 residues, revealed a thi ... | 1993 | 7682244 |
| bee venom hyaluronidase is homologous to a membrane protein of mammalian sperm. | the venom of honeybees, apis mellifera, contains several biologically active peptides and two enzymes, one of which is a hyaluronidase. by using degenerate oligonucleotides derived from the amino-terminal sequence of this hyaluronidase reported by others, clones encoding the precursor for this enzyme could be isolated from a cdna library prepared from venom glands of worker bees. the deduced amino acid sequence showed that bee venom hyaluronidase is a polypeptide composed of 349 amino acids cont ... | 1993 | 7682712 |
| characterization of murine monoclonal antibodies to phospholipase a2 and mellitin from bee venom. | 9 murine monoclonal antibodies (moabs), 7 to phospholipase a2 (pla2; api m i) and two to mellitin (api m iii) have been produced. specificities were demonstrated using immunoblotting and enzyme immunoassays (elisa). antibodies specific for pla2 were characterized in detail. epitope mapping of pla2-specific moabs identified three independent binding regions. 5 selected moabs bound to one of these sites compete with specific human ige. two of moabs characterized are suitable tools to quantify pla2 ... | 1993 | 7685217 |
| complete base sequence for the mitochondrial large subunit ribosomal rna of the gypsy moth lymantria dispar (l.). | a 1355 bp sequence (accession number l32141) isolated from a gypsy moth (lymantria dispar) cdna library showed 68-74% sequence identity to mitochondrial large subunit ribosomal rna (mt irrna) sequences of locusta migratoria, apis mellifera, aedes albopictus, anopheles gambiae and two drosophila species. a comparison of the primary sequences of the mt irrnas from the above insects in four orders and from esherichia coli demonstrated regions of conservation which presumably correspond to regions o ... | 1994 | 7704305 |
| phospholipase a2-activating protein induces the synthesis of il-1 and tnf in human monocytes. | phospholipase a2-activating protein (plap) is an important mediator of eicosanoid generation. plap can also be found in high concentrations in synovial fluid from patients with rheumatoid arthritis, and injection of plap into animal joints results in an inflammatory, rheumatoid-like lesion. we have demonstrated previously that tnf-alpha and il-1 beta stimulate formation of plap before phospholipase a2 (pla2) enzyme activation and production of eicosanoids. to further explore the mechanisms found ... | 1995 | 7706741 |
| effects of inorganic phosphorus compounds on the hydrolysis of phosphatidylcholine liposomes by phospholipid-deacylating enzymes. | structural requirements of inorganic phosphorus compounds as specific activators or inhibitors for phospholipase a2 and phospholipase b were investigated using orthophosphate, pyrophosphate and polyphosphate. it was observed that orthophosphate and pyrophosphate stimulated the activities of phospholipase a2 from bee venom, snake (naja naja) venom and pig pancreas, and also phospholipase b from the yeast torulaspora delbrueckii. however, polyphosphate was found to act as an inhibitor for phosphol ... | 1995 | 7710702 |
| localization of octopaminergic neurones in insects. | this paper reviews data on the localization of octopaminergic neurons revealed by immunocytochemistry in insects, primarily the locusts schistocerca gregaria and locusta migratoria, cricket gryllus bimaculatus, and cockroach periplaneta americana. supporting evidence for their octopaminergic nature is mentioned where available. in orthopteran ventral ganglia, the major classes of octopamine-like immunoreactive (-li) neurones include: (1) efferent dorsal and ventral unpaired median (dum, vum) neu ... | 1995 | 7712064 |
| [cloning and expression of a plasmid pbs195 gene, determining oxygenase activity, in escherichia coli cells]. | plasmid pbs195, detected in a strain of lactobacillus sp. isolated from long-living persons, has a broad host range, including gram-positive and gram-negative microorganisms [1]. plasmid-harboring colonies of the strain escherichia coli hb101 give a color reaction with catechol. this indicates that genes mediating the activity of oxygenase are present in this plasmid. the high activity level of this enzyme, mediated by pbs195, and substrate specificity, which has not bee detected in any known me ... | 1995 | 7721057 |
| direct effects of recombinant nuclear polyhedrosis viruses on selected nontarget organisms. | a limitation to effective field use of naturally occurring nuclear polyhedrosis viruses (npvs) is the slow rate at which they kill their host. in making npvs a more attractive pest management tool, this problem has been addressed by modifying npvs genetically to express insecticidal proteins resulting in substantial increases in their speed of action. one concern associated with these recombinant npvs, however, is their effects on nontarget insects associated with pests targeted for control by a ... | 1995 | 7722081 |
| [prevalence of pneumocystosis in hiv infected patients in a pneumology unit. autopsy study performed in abidjan (côte d'ivoire)]. | autopsies were performed in the pathology department of the treichville university hospital, abidjan, ivory coast in 70 hiv infected subjects who had died in the department of pneumophtisiology. the prevalence of pneumocystis carinii pneumonia was determined. none of the patients had received prophylaxis against p. carinii and none had bee treated for pneumocystosis. autopsies were performed within 6 to 48 hours after death and the diagnosis of pneumocystosis was confirmed with the gomori-grocot ... | 1994 | 7724970 |
| melittin increases ampa receptor affinity in rat brain synaptoneurosomes. | recent experimental evidence suggests that phospholipase-induced changes in binding properties of the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (ampa) subtype of glutamate receptors account for the increase in synaptic response observed in long-term potentiation (ltp). in the present study, we report that treatment of rat telencephalic synaptoneurosomes with the bee venom peptide melittin, a potent activator of endogenous phospholipases, increased [3h]ampa binding to the ampa recepto ... | 1995 | 7743208 |
| [effect of bee pollen on maternal nutrition and fetal growth]. | plant pollen collected by the honeybee is called bee pollen, which is a natural nutrient. we studied the effects of the bee pollen of brassia campestres l. on maternal nutrition and fetal growth. pregnant sprague-dawley rats at o-d were divided randomly into three groups. the control group (c) was fed with a diet. the other two groups (a) and (b) were fed with the diet plus bee pollen 20 g/kg.d-1 and 10 g/kg.d-1, respectively. all the dams in each group took a diet and drank water and libitm. po ... | 1994 | 7744390 |
| phospholipase a2 domain formation in hydrolyzed asymmetric phospholipid monolayers at the air/water interface. | phospholipase a2 (pla2) catalyzed hydrolysis of asymmetric 1-caproyl-2-palmitoyl-phosphatidylcholine (6,16-pc) and 1-palmitoyl-2-caproyl-phosphatidylcholine (16,6-pc) lipid monolayers at the air/water interface was investigated. surface pressure isotherms, surface potential and fluorescence microscopy at the air/water interface were used to characterize the asymmetric monolayer systems. cobra (n. naja naja) and bee venom pla2 exhibit hydrolytic activity towards 16,6-pc monolayers at all surface ... | 1995 | 7756350 |
| [study of conformation transitions in proteins by tryptophan fluorescence and phosphorescence at low temperatures]. | the well-known conformational changes in proteins containing a single tryptophan residue, such as ph-induced n-->f transition in human serum albumin, ph-induced acidic transition in cod parvalbumin, and kcl-induced tetramerization of bee venom melittin were monitored by changes in low temperature phosphorescence and fluorescence spectra suggesting two independent series of normal components. parameters of low temperature tryptophan luminescence were sensitive to chromophore environment. a correl ... | 1995 | 7783738 |
| [immunomodulatory effect of honeybee flower pollen load]. | primary and secondary humoral immune response (the level of specific igm and igg) as well as the intensity of delayed-type hypersensitivity to sheep erythrocytes were investigated in rabbits fed with apis flower pollen load for a month. it is shown that apis flower pollen load is an immunomodulator. it stimulated humoral immune response and changed the reaction of delayed-type hypersensitivity. | 1994 | 7785092 |
| [antioxidant system of rat erythrocytes under conditions of prolonged intake of honeybee flower pollen load]. | the state of erythrocyte redox system of rats feeding on apis flower pollen load during a month was investigated. it was established that the content of glutathione, total sh-groups as well as activities of glutathione peroxidase and glutathione reductase in these animals in comparison with the control group were increased. simultaneously a decrease of malondialdehyde and dienic conjugates in erythrocytes was shown. the activity of catalase and superoxide dismutase were increased, but it was not ... | 1994 | 7785093 |
| biochemical characterization of a glycosylphosphatidylinositol-linked hyaluronidase on mouse sperm. | on the basis of dna homology to bee venom hyaluronidase, it was recently suggested that the gpi-linked mammalian sperm antigen, ph-20, may function as a cell surface hyaluronidase [gmachl, m., & kreil, g. (1993) proc. natl. acad. sci. u.s.a. 90, 3569-3573]. we have quantified the activity of the soluble acrosomal hyaluronidase of mouse sperm and further demonstrate the existence of a membrane-bound hyaluronidase, detected on both acrosome-intact and acrosome-reacted mouse sperm, distinct from th ... | 1995 | 7794889 |
| the asparagine-linked carbohydrate of honeybee venom hyaluronidase. | hyaluronidase from the venom of the honeybee (apis mellifera) has been purified by gelpermeation and cation exchange chromatography. its asparagine-linked carbohydrate chains were released from tryptic glycopeptides with n-glycosidase a and reductively aminated with 2-aminopyridine. separation of the fluorescent derivatives by size-fractionation and reversed-phase hplc afforded eighteen fractions which were analysed by two-dimensional hplc mapping combined with exoglycosidase digestions. the bul ... | 1995 | 7795417 |
| induction by melittin of protein phosphorylation in bovine mammary gland and suppression of the phosphorylation by phosphatidylserine. | the protein kinase c (pkc) inhibitor sphingosine induces phosphorylation of an 18-kda protein in jurkat t cells and of a 19-kda protein in bovine mammary gland, and suppresses phosphorylation of substrate proteins for pkc. melittin, a toxic amphiphilic peptide from bee venom known to inhibit pkc activity, was examined to determine whether it, like sphingosine, induced phosphorylation of the 19-kda protein. melittin inhibited pkc activity in both cytosolic and total particulate fractions of bovin ... | 1994 | 7801316 |
| altered glycosylation and selected mutation in recombinant human complement component c9: effects on haemolytic activity. | recombinant wild-type and mutated forms of human complement component c9 have been synthesized in baculovirus-infected insect cells. wild-type recombinant c9 was indistinguishable from native c9, as judged by haemolytic activity, trypsin and alpha-thrombin digestion, reaction with antibodies to c9, enzymatic deglycosylation to the same core size and polymerization in the presence of zn2+. replacement of the native signal peptide with the honey-bee melittin signal peptide, and replacement of spod ... | 1994 | 7835977 |
| carbohydrate-dependent, hla class ii-restricted, human t cell response to the bee venom allergen phospholipase a2 in allergic patients. | the t cell-independent antibody response to polysaccharide antigen (ag) is believed to result from their inability to bind major histocompatibility complex (mhc) restriction elements. however, recent studies using glycosylated analogues of known immunogenic peptides revealed that glycopeptides can interact with mhc molecules and are able to elicit specific t cell responses in experimental animals. this raises questions about the possible role which carbohydrates can play in t cell responses foll ... | 1995 | 7875217 |
| sequence identity and antigenic cross-reactivity of white face hornet venom allergen, also a hyaluronidase, with other proteins. | white face hornet (dolichovespula maculata) venom has three known protein allergens which induce ige response in susceptible people. they are antigen 5, phospholipase a1, and hyaluronidase, also known as dol m 5, 1, and 2, respectively. we have cloned dol m 2, a protein of 331 residues. when expressed in bacteria, a mixture of recombinant dol m 2 and its fragments was obtained. the fragments were apparently generated by proteolysis of a met-met bond at residue 122, as they were not observed for ... | 1995 | 7876212 |
| horizontal transmission, vertical inactivation, and stochastic loss of mariner-like transposable elements. | horizontal transmission has been well documented as a major mechanism for the dissemination of mariner-like elements (mles) among species. less well understood are mechanisms that limit vertical transmission of mles resulting in the "spotty" or discontinuous distribution observed in closely related species. in this article we present evidence that the genome of the common ancestor of the melanogaster species subgroup of drosophila contained an mle related to the mellifera (honey bee) subfamily. ... | 1995 | 7877497 |
| solubilization of neuropathy target esterase and other phenyl valerate carboxylesterases from chicken embryonic brain by phospholipase a2. | membrane-bound neuropathy target esterase (nte) and associated phenyl valerate carboxylesterases were solubilized from chicken embryo brain by phospholipase a2. phospholipase a2 from bee or cobra (naja) venoms were the most effective preparations in solubilizing brain nte and other phenyl valerate carboxylesterases. phospholipase c and several proteinases (endoproteinase, pronase e, proteinase k, thermolysin, trypsin) did not solubilize brain membrane-bound carboxylesterases but reduced their ac ... | 1994 | 7881804 |
| addition-order dependent modulation of the sensitivity of rabbit erythrocyte membrane to bee venom phospholipase a2 by oleic acid, lysophosphatidyl choline and albumin. | the addition of exogenous oleic acid to erythrocyte membranes induces a characteristic membrane crenation and sensitises the cells to the lytic action of phospholipase a2 enzymes. both effects are extremely sensitive to inhibition by endogenous lysophosphatidyl choline (lpc), but the strength of inhibition depends of the order in which the reagents are added to the cells. these responses are further enhanced when the reagents are extracted from the cell membranes by treatment with albumin. thus ... | 1994 | 7886704 |
| cdna sequence and expression of the ceratotoxin gene encoding an antibacterial sex-specific peptide from the medfly ceratitis capitata (diptera). | ceratotoxins are antibacterial 3-kda molecular mass amphiphilic peptides isolated from the female reproductive accessory glands of the medfly ceratitis capitata. they are physiologically related to bee melittin and show amino acid sequence homology with magainin peptides. in this paper, we report the complete sequence of cdna coding for ceratotoxin a and the expression of the gene during the life cycle of the insect. experimental data show that the ceratotoxin is a gene expressed exclusively in ... | 1995 | 7890755 |
| allozyme polymorphisms in spanish honeybees (apis mellifera iberica). | earlier studies have shown two types of mitochondrial dna in spanish honeybees (apis mellifera iberica): a western european or a. m. mellifera type, which predominates in northern spain, and a north african or a. m. intermissa type, which predominates in southern spain. adult workers from 28 colonies sampled in northern and southern spain were surveyed for polymorphisms at eight allozyme loci. polymorphisms were found in mdh1 (two alleles) and pgm (five alleles). three of the pgm alleles have no ... | 1995 | 7890926 |
| learning and memory in the honeybee. | insects are favorable subjects for neuroethological studies. their nervous systems are relatively small and contain many individually identifiable cells. the cns is highly compartmentalized with clear separations between multisensory higher order neuropiles in the brain and neuropiles serving sensory-motor routines in the ventral cord (huber, 1974). the rich behavior of insects includes orientation in space and time, visual, chemical, and mechanical communication, and complex motor routines for ... | 1995 | 7891123 |
| electrophysiological properties of guinea pig trigeminal motoneurons recorded in vitro. | 1. intracellular recording and stimulation were made from guinea pig trigeminal motoneurons (tmns) in brain stem slices. electrophysiological properties were examined and the underlying currents responsible for motoneuron excitability were investigated by the use of current clamp and single electrode voltage clamp (sevc) techniques. 2. the voltage responses to subthreshold hyperpolarizing or depolarizing current pulses showed voltage- and time-dependent inward rectification. sevc analysis demons ... | 1994 | 7908952 |
| cloning of an apamin binding protein of vascular smooth muscle. | the receptor for the bee venom derived neurotoxin, apamin, is widely believed to be an integral component of the small conductance calcium-activated potassium channel in many excitable cells. by affinity chromatography on immobilized apamin, a 78 kd apamin binding protein of the bovine brain synaptosomes was isolated. antibodies were elicited against this protein and used to clone a cdna from a porcine vascular smooth muscle expression library. this gene (kcal 1.8) codes for a 438 amino protein ... | 1994 | 7912073 |
| the spatial and temporal dynamics of sax1 (chox3) homeobox gene expression in the chick's spinal cord. | sax1 (previously chox3) is a chicken homeobox gene belonging to the same homeobox gene family as the drosophila nk1 and the honeybee hho genes. sax1 transcripts are present from stage 2 h&h until at least 5 days of embryonic development. however, specific localization of sax1 transcripts could not be detected by in situ hybridization prior to stage 8-, when sax1 transcripts are specifically localized in the neural plate, posterior to the hindbrain. from stages 8- to 15 h&h, sax1 continues to be ... | 1994 | 7924989 |
| development of a new, more sensitive immunoassay for human tryptase: use in systemic anaphylaxis. | tryptase, a neutral protease, is selectively concentrated in the secretory granules of human mast cells, and its release into the circulation serves as a clinical marker of mast cell activation. the current study describes a new, more sensitive elisa utilizing a newly developed, mouse monoclonal igg1 antibody for capture called b12 and capable of detecting tryptase in normal plasma and serum. the greater sensitivity of the new immunoassay results in part from a greater portion of tryptase being ... | 1994 | 7929694 |
| severe and fatal mass attacks by 'killer' bees (africanized honey bees--apis mellifera scutellata) in brazil: clinicopathological studies with measurement of serum venom concentrations. | in são paulo state, brazil, five males, aged between 8 and 64 years, were attacked by 'africanized' honey bees (apis mellifera scutellata). the estimated number of stings received by each patient ranged from > 200 to > 1000. all five were transferred to intensive care units in são paulo city. clinical features included intravascular haemolysis, respiratory distress with ards, hepatic dysfunction, rhabdomyolysis (with myoglobinaemia and myoglobinuria), hypertension and myocardial damage (perhaps ... | 1994 | 7938407 |
| invertebrate vision. bees learn how to look. | honey bee vision, like human vision, involves active learning: the bees adjust the way they scan a scene so as to improve their uptake of useful information. | 1994 | 7953559 |
| in vivo monitoring system for structure-function relationship analysis of the antibacterial peptide apidaecin. | a unique antibacterial peptide derivative found in immune honeybee lymph, apidaecin 1b (ap1), was randomly mutagenized and characterized by a newly established system to analyze in vivo its structure-function relationship. initially, a high-level expression host-vector system for ap1 in escherichia coli was constructed by creating a fusion protein with the highly stable streptomyces subtilisin inhibitor (ssi) molecule. expression of the ssi-ap1 fusion protein was found to depend on the concentra ... | 1994 | 7986034 |
| the relationship between phospholipid content and ca2+-atpase activity in the sarcoplasmic reticulum. | the relationship between the phospholipid composition of sarcoplasmic reticulum and the activity of the ca2+, mg2+-stimulated atpase was analyzed by digestion of membrane phospholipids with phospholipase c and a2 enzymes of diverse specificity and by detergent extraction. phospholipase c of clostridium perfringens and clostridium welchii, that hydrolyze preferentially phosphatidylcholine (pc), inhibited the ca2+-atpase activity parallel with the depletion of phosphatidylcholine from the membrane ... | 1994 | 7986804 |
| modulation of the delayed rectifier k+ current by apamin in guinea-pig heart. | modulation of the cardiac delayed rectifier k+ current (ik) by apamin was studied in guinea-pig ventricular myocytes using the whole-cell configuration of the patch-clamp technique. apamin, a peptide toxin isolated from bee venom, is known to inhibit ca(2+)-activated k+ channel activity. bath application of apamin prolonged the action potential duration and partially inhibited ik in a concentration-dependent fashion with a half-maximal concentration of 34.4 nm and a hill coefficient of 1.2. the ... | 1994 | 8001647 |
| multiplication of clostridium botulinum in dead honey-bees and bee pupae, a likely source of heavy contamination of honey. | multiplication of clostridium botulinum in honey-bees was examined to explain the heavy contamination of honey which may occur with this pathogen. when dead bees were inoculated with c. botulinum spores at levels of 10(2)-10(3) and incubated aerobically for 10 days, the organisms increased to 10(4)-10(5). when botulinum spores were inoculated together with bacillus alvei, the growth of most strains was significantly enhanced (10(5)-10(7)). similar results were obtained in bee pupae, but not in b ... | 1994 | 8024976 |
| comparable 30-kda apamin binding polypeptides may fulfill equivalent roles within putative subtypes of small conductance ca(2+)-activated k+ channels. | apamin, a peptide neurotoxin from bee venom, blocks small conductance ca(2+)-activated k+ channels in central synapses and peripheral tissues. using 125i-apamin, single classes of high affinity binding sites (kd 1-3 pm) were identified on plasma membranes from rat, rabbit, guinea pig, and bovine brain and from rabbit, guinea pig, and bovine liver. binding was sensitive to scyllatoxin, dequalinium, gallamine, and d-tubocurarine but not to charybdotoxin, toxin i, or mast cell degranulating peptide ... | 1994 | 8027065 |
| bacillus dna in fossil bees: an ancient symbiosis? | we report here the isolation of dna from abdominal tissue of four extinct stingless bees (proplebeia dominicana) in dominican amber, pcr amplification of a 546-bp fragment of the 16s rrna gene from bacillus spp., and their corresponding nucleotide sequences. these sequences were used in basic local alignment search tool searches of nonredundant nucleic acid data bases, and the highest scores were obtained with 16s rrna sequences from bacillus spp. phylogenetic inference analysis by the maximum-l ... | 1994 | 8031102 |
| peptide amidation in an invertebrate: purification, characterization, and inhibition of peptidylglycine alpha-hydroxylating monooxygenase from the heads of honeybees (apis mellifera). | peptidylglycine alpha-hydroxylating monooxygenase (phm), an enzyme involved in formation of neuropeptides with a c-terminal amide functionality in mammals and amphibians, was isolated from the head of an invertebrate, the honeybee, apis mellifera, and purified 220-fold in 1% overall yield. the bee phm has a molecular weight of 71,000, is membrane associated but can be solubilized with a detergent (n-octyl-beta-d-glucopyranoside), and cross-reacts with rabbit antibodies generated toward bacterial ... | 1994 | 8054657 |
| cardiac noradrenaline in experimental rat envenomation with africanized bee venom. | the concentration of cardiac tissue noradrenaline (nor) was determined in wistar rats injected with 1.5 microliters/100 g body weight africanized bee venom (abv) (ld50 = 0.8 microliter/100 g body weight by the intravenous route). the animals were injected with abv by the intramuscular (im), intraperitoneal (ip), subcutaneous (sc) and intravenous (iv) routes. animals injected by the im, ip and sc routes were sacrificed 4, 7 and 24 hours after injection. the animals injected by the iv route were s ... | 1994 | 8054829 |
| pneumolysin activates phospholipase a in pulmonary artery endothelial cells. | pneumolysin has been identified as a virulence factor in streptococcus pneumoniae disease. in addition to producing tissue injury through its cytolytic effect, pneumolysin might injure tissues indirectly by eliciting an inflammatory response. we demonstrate for the first time that pneumolysin is a rapid and potent activator of cellular phospholipase a in bovine pulmonary artery endothelial cells. in contrast to other toxin-activated phospholipases, pneumolysin-stimulated phospholipase a showed n ... | 1994 | 8063399 |
| expression and export in escherichia coli of fusion proteins containing carboxy-terminally located honeybee prepromelittin. | the aim of this work was to express a eukaryotic pre-protein in escherichia coli so that it could be obtained intact, without cleavage, by bacterial leader peptidase. to this end, cdna coding for honeybee prepromelittin was ligated to the 3' end of genes coding for truncated forms of either protein a or beta-galactosidase (beta-gal) under the control of inducible promoters, with an oligonucleotide coding for the factor xa cleavage site at the junction between the two proteins. the protein a fusi ... | 1994 | 8068210 |
| groups i, ii and iii extracellular phospholipases a2: selective inhibition of group ii enzymes by indomethacin but not other nsaids. | the three types (groups i, ii and iii) of stable extracellular 14 kda phospholipase a2 enzymes differ in their primary amino acid sequences and their properties. it may thus be possible to design low-molecular weight inhibitors targeted to the secretory form of mammalian pla2. this enzyme has been implicated in inflammatory disorders. we have studied the inhibition of four distinct pla2 enzymes by a range of nsaids, using 3h-oleate release from prelabelled membranes of e. coli for assay. the enz ... | 1994 | 8079814 |
| control of expression, glycosylation, and secretion of hiv-1 gp120 by homologous and heterologous signal sequences. | the hiv-1 gp120 signal sequence of 30 amino acids is longer than most glycoprotein signal sequences and contains an average of 5 positively charged amino acids. the hiv-1 gp120 gene with its natural signal sequence expressed in any prokaryotic or eukaryotic expression systems showed extremely low levels of synthesis and secretion. however, deletion of the hiv-1 gp120 signal sequence results in production of large quantities of a nonglycosylated form of gp120 in spodoptera frugiperda cells. subst ... | 1994 | 8091657 |
| melittin potentiates guanylate cyclase activation stimulated by atrial natriuretic factor and atp. | the biologically relevant receptor for atrial natriuretic factor (anf) has been shown to be membrane-bound guanylate cyclase. while guanylate cyclase is known to be activated by anf and atp, the molecular mechanism of the enzyme activation remains unclear. we now show that melittin, the main peptide toxin of bee venom, activates membrane-bound guanylate cyclase and potentiates anf- and atp-stimulated guanylate cyclase activity in rat lung membranes. melittin stimulated basal guanylate cyclase ac ... | 1993 | 8095264 |
| ricin enhances ige responses by inhibiting a subpopulation of early-activated ige regulatory cd8+ t cells. | ricin, a toxic lectin from castor beans greatly enhances ige responses to bee venom phospholipase a2 (pla2) in high and low ige responder strains of rat. the increase in ige is accompanied by a 60% reduction in the number of cd8+ but not cd4+ t cells in the spleen. optimal enhancement of ige by ricin occurs when it is given at the same time as the antigen or 24 hr later, suggesting that it acts on cells which were activated as a consequence of immunization. radio ligand-binding studies with 125i ... | 1993 | 8097181 |
| genomic organization and expression of the planarian homeobox genes dth-1 and dth-2. | we have characterized the genomic organization of dth-1 and dth-2, planarian homeobox-containing genes, previously described at the cdna level (j. garcia-fernàndez, j. baguñà and e. saló (1991), proc. natl. acad. sci. usa, 88, 7338-7342). genomic analysis shows that dth-1 and dth-2 genes encode proteins of 533 and 363 amino acids respectively. the open reading frame of dth-1 is interrupted by two large introns of 8 kb and 12 kb dth-2 also shows two introns, but these are short (42 bp and 44 bp) ... | 1993 | 8104142 |
| inferences concerning crossbridges from work on insect muscle. | this paper presents a number of separate results concerning crossbridge attachment: [1] x-ray diffraction from live bumble bee flight muscle shows a set of layer lines distinct from that of relaxed lethocerus, in which the apparent myosin helix is shorter than that of the actin. [2] rigor crossbridges of lethocerus are not rotatable by stretch. [3] rabbit and lethocerus fibres in rigor relaxed by atp at -35 degrees c show evidence of non-rigor crossbridge attachment. | 1993 | 8109367 |
| [the effect of varroa jacobsoni invasion on bee colonies with queens of different breeds in the fourth year of the disease]. | the objective of the work was to determine the effect of invasion of varroa jacobsoni on the bee colonies of different breeds in the fourth year of varrosis. it was found out that bee colonies which were not treated died in the fourth year of the disease, while treated ones were debilitated. the main loss concerned the bee colonies with augustonian and carnica queens. the most resistant were colonies with caucasian queens. | 1993 | 8122424 |
| deaths from bee stings. | | 1994 | 8128565 |
| [effectiveness of the preparation of bayvarol-strips (r) in control of varroa jacobsoni mites]. | there were investigated plastic strips with active ingredient flumethrin: bayvarol-strips (r). there were used 4 strips for a treatment. they were placed between combs of honey bee colony. the mean effectiveness of te medication was 95.6%. bayvarol-strips (r) were harmless for bees. | 1993 | 8128731 |
| melittin-binding of troponin c. | ca(2+)-dependent interaction between skeletal muscle troponin c and a bee venom melittin, which can be regarded as a mimic of the troponin c-binding peptide of troponin i, was investigated. sephadex gel chromatography revealed that melittin bound to troponin c irrespective of the presence or absence of ca2+ in 50 mm kcl and 50 mm tris-hcl, ph 7.5. at high salt concentration, 0.5-1.2 m kcl, melittin was removed from apo troponin c but still bound to ca(2+)-loaded troponin c. hydrophobic affinity ... | 1993 | 8138531 |
| cytolytic and antibacterial activity of synthetic peptides derived from amoebapore, the pore-forming peptide of entamoeba histolytica. | the pore-forming peptide amoebapore is considered part of the cytolytic armament of pathogenic entamoeba histolytica. amoebapore is composed of 77 amino acid residues arranged in four alpha-helical domains. for structure-function analysis, synthetic peptides were constructed corresponding to these four domains: h1 (residues 1-22), h2 (25-39), h3 (40-64), and h4 (67-77). the peptides h1 and h3, representing two highly amphipathic alpha-helical regions of amoebapore, possessed pore-forming activit ... | 1994 | 8146160 |
| polymers for delivering peptides and proteins. | the use of polymers for delivering peptide and protein drugs is described. soluble-polymer technology attempts to bind a polymer to all sites on therapeutic protein molecules that cause the body to recognize the molecules as foreign. goals include a stable linkage, water solubility, low immunogenicity, prolonged half-life, and intact biological activity. polyethylene glycol (peg)-adenosine deaminase (ada), or pegademase bovine, has fda-approved labeling as replacement therapy for ada deficiency ... | 1994 | 8160672 |
| anti-ige autoantibodies in asthma: a diagnostic artefact or an explanation for non-allergic asthma? | autoantibodies to ige can be detected in sera of individuals with atopic disease, but occasionally elevated levels are also found in sera of normal individuals. during the last years we studied therefore the functional properties of such autoantibodies. depending on the studied in vitro system one can always detect minimally two different antibody types. antibodies have been found that either trigger or inhibit mediator release from basophils, that enhance or inhibit binding of ige to the low ig ... | 1994 | 8171227 |
| deaths from bee stings. | | 1994 | 8171803 |
| improved cumulated nitrogen balance after administration of recombinant human growth hormone in patients undergoing gastrointestinal surgery. | to examine the effect of recombinant human growth hormone (rhgh) on the catabolic state following major gastrointestinal surgery. | 1994 | 8173309 |
| rate and quantity of delivery of venom from honeybee stings. | to determine the rate and completeness of delivery of venom from honeybee stings, european bees were collected at the entrance of a hive and studied with the use of two laboratory models. in one model bees were induced to sting the shaved skin of anesthetized rabbits. the stings were removed from the skin at various time intervals after autotomization, and residual venom was assayed with a hemolytic method. in the other model the bees were induced to sting preweighed filter paper disks, which we ... | 1994 | 8182223 |
| antigenic surface of the bee venom allergen phospholipase a2. structural functional analysis of human igg4 antibodies reveals potential role in protection. | in the human immune response to the main bee venom allergen phospholipase a2 (pla2), abs of the igg4 isotype are associated with protection. the antigenic sites of pla2 that are recognized by two mab of this isotype have been analyzed at the molecular level. the interaction of pla2 with these two abs has previously been shown to depend on the conformation of the ag and to be sensitive to lysine modifications. therefore, genetically engineered ag displaying single point mutations of lysine residu ... | 1994 | 8189069 |
| electrophysiological characteristics of immunochemically identified rat oxytocin and vasopressin neurones in vitro. | 1. intracellular recordings were made from supraoptic neurones in vitro from hypothalamic explants prepared from adult male rats. neurones were injected with biotinylated markers, and of thirty-nine labelled neurones, nineteen were identified immunocytochemically as containing oxytocin-neurophysin and twenty as containing vasopressin-neurophysin. 2. vasopressin and oxytocin neurones did not differ in their resting membrane potential, input resistance, membrane time constant, action potential hei ... | 1994 | 8189384 |
| enhancement of protein synthesis efficiency in parenterally fed trauma victims by adjuvant recombinant human growth hormone. | in the early catabolic phase of severe injury, conventional nutritional support is inadequate to reverse negative nitrogen balance and an anabolic stimulus may be beneficial. the utilization efficiency of body energy sources after injury could be improved by adjuvant recombinant human growth hormone (rhgh) therapy. we measured the protein kinetic response to exogenous rhgh in trauma patients fed parenterally (tpn). severely injured (mean iss, 31 +/- 2), highly catabolic (mean nitrogen loss, 19 + ... | 1994 | 8189476 |
| dna fingerprinting analysis of parent-offspring conflict in a bee. | demonstrating the importance of haplodiploidy in the evolution of eusociality among the hymenoptera (bees, wasps, and ants) requires estimation of four parameters: relatedness between cooperating individuals, effective mating frequency, sex ratio, and rates of worker reproduction. multilocus dna fingerprinting techniques permitted the precise determination of these parameters for the primitively eusocial bee augochlorella striata (halictidae). dna fingerprints revealed an unprecedented resolutio ... | 1994 | 8197197 |
| deaths from bee stings. | | 1994 | 8197691 |
| phospholipid asymmetry in plasma membrane vesicles derived from bhk cells. | the transbilayer distribution of phospholipids in plasma membrane vesicles derived from bhk cells by treatment with iodoacetamide or fluoride and merocyanine 540 has been examined by exposing the vesicles to bee venom phospholipase a2 (pla2) or to bacillus cereus sphingomyelinase. the results show that almost all of the phosphatidylserine (ps) is on the inner lipid leaflet and most of the sphingomyelin is on the outer lipid leaflet. in contrast, about 50% of the phosphatidylcholine (pc) and 30-4 ... | 1994 | 8204655 |
| toxic effects of human pancreatic and snake and bee venom phospholipases a2 on mcf-7 cells in culture. | the toxicity of phospholipase a2 (pla2) has been suggested to be involved in the pathology of a number of severe diseases including septic shock and acute pancreatitis. however, testing the toxicity of these substances is difficult in vivo. in the present study we compared the toxicity of pla2s from three snake venoms, bee venom and human pancreas on mcf-7 cells grown in culture. tetrazolium microculture assays were developed to test the cytostatic and cytotoxic effects of pla2 on mcf-7 cells. t ... | 1993 | 8212029 |
| [an immunological study of workers exposed to diphenylmethane diisocyanate (mdi)]. | the average (od values) and positive rates of specific ige antibodies to a mdi-human serum albumin (hsa) conjugate in 25 workers exposed to mdi were significantly lower than those in 8 subjects of mdi asthma, while they were significantly higher than those in the 30 control subjects who had never bee exposed to mdi before. the positive rates of specific ige antibodies in symptomatic mdi-workers were significantly higher than those in asymptomatic mdi-workers. the results of studies of specific i ... | 1993 | 8243177 |
| demonstration of membrane-associated phospholipase a2 in cultivated heart muscle cells by immunogold-technique in surface replicas. | recently we produced mab's to phospholipase a2 (pia2) from bee venom for different purposes (allergen-identification and -standardization). obviously one of these monoclonal antibodies "5d5" binds to a conserved (cross reactive) epitope of membrane pia2 of intact cells. in this study we demonstrate binding of 5d5 to membrane associated phospholipase a2 of rat heart muscle cells by means of two-step immunogold technique in combination with replica technique. | 1993 | 8279236 |
| high-level expression and purification of secreted forms of herpes simplex virus type 1 glycoprotein gd synthesized by baculovirus-infected insect cells. | two forms of herpes simplex virus glycoprotein gd were recombined into autographa californica nuclear polyhedrosis virus (baculovirus) and expressed in infected spodoptera frugiperda (sf9) cells. each protein was truncated at residue 306 of mature gd. one form, gd-1(306t), contains the coding sequence of patton strain herpes simplex virus type 1 gd; the other, gd-1(qaat), contains three mutations which eliminate all signals for addition of n-linked oligosaccharides. prior to recombination, each ... | 1994 | 8289380 |
| human leukocytes contain angiotensin i, angiotensin ii and angiotensin metabolites. | angiotensin i (ang i) and angiotensin ii (ang ii) were measured radioimmunologically in human leukocytes extracted with a mixture of acetone, 1n hcl and water (40:1:10 vol). the analytical recoveries of 125i-ang i and 125i-ang ii, which were added prior to extraction, were 92.00 +/- 3.10 and 99.19 +/- 0.91% (mean +/- sem; n = 12). the concentration of ang i- and ang ii-like material in leukocytes from healthy volunteers was 32.04 +/- 3.64 and 13.05 +/- 1.26 fmol/mg protein (n = 24). the immunore ... | 1994 | 8292902 |
| [clinical and experimental investigation on the radioprotective effect of riboxine in low-dose fractionated irradiation]. | in experiments with dogs (fractionated y-irradiation, accumulated dose 1gy) as well as in clinical testing of the group of men, recieved 0,25 gy being engaged in the chernobyl nps disaster repairment, the positive influence of riboxin (purine nucleoside) course treatment on parameters of peripheral blood and non-specific resistance system has bee n shown. | 1993 | 8293105 |
| glycosylation and high-level secretion of human tumour necrosis factor-beta in recombinant baculovirus-infected insect cells. | human tumour necrosis factor-beta (tnf-beta) was produced in eukaryotic cells using the insect baculovirus cloning and expression system. a novel insect signal sequence, the honey-bee (apis mellifera) prepromelittin secretory sequence, was used to aid in the post-translational modifications, glycosylation and secretion of recombinant human tnf-beta. human tnf-beta cdna was cloned using the insect baculovirus vector pacc4s. expression of the human tnf-beta was regulated by the insect autographa c ... | 1993 | 8297505 |
| transfer of paternal mitochondrial dna during fertilization of honeybee (apis mellifera l.) eggs. | strict maternal inheritance of mitochondrial (mt) dna is believed to be the rule in most eukaryotic organisms because of exclusion of paternal mitochondria from the egg cytoplasm during fertilization. in honeybees, polyspermic fertilization occurs, and many spermatozoa, including their mitochondria-rich flagellum, can completely penetrate the egg, thus allowing for a possibly high paternal leakage. in order to identify paternal mtdna in honeybee eggs, restriction fragment length polymorphisms (r ... | 1993 | 8299176 |
| a g protein-activated k+ current in bovine adrenal chromaffin cells: possible regulatory role in exocytosis. | guanine nucleotide binding proteins (g proteins) act as signal transducers between membrane receptors and ion channels. in the present study, the whole-cell arrangement of the patch clamp technique was used to examine the effect of g proteins on k+ channels in cultured bovine adrenal chromaffin cells. internal dialysis of chromaffin cells with guanosine 5'-o-(3-thiotriphosphate) (gtp gamma s) or external application of aif-4, to stimulate g proteins, resulted in a voltage-dependent increase in t ... | 1994 | 8302269 |
| is an amphiphilic region responsible for the haemolytic activity of bacillus thuringiensis toxin? | the amino acid sequence of the 27 kda protein responsible for the haemolytic activity of bacillus thuringiensis subsp. israelensis toxin has been analysed by secondary structure prediction, helical wheel/net diagrams and molecular mechanics calculations. we found that segment 116-126 presumably forms a strongly amphiphilic alpha-helix. this is supported by the findings that the synthesized segment 116-126 (a) has a significant alpha-helical content in water, and (b) displays an in vitro haemolyt ... | 1993 | 8307684 |
| effect of a series of 1-alkyl ether lipids on inhibition of phospholipase a2 activity and paf responses. | several 1-alkyl ether lipids were studied for their ability to inhibit pla2 and antagonize paf responses. studies with synthetic micellar substrate (1-stearyl-2-arachidonyl phosphocholine), at concentrations ranging from 0.02 to 1000 microm, demonstrate that cl 118326 inhibits porcine pancreatic pla2 in vitro. as the substrate concentration increases, there is a dose-dependent increase in the ic50 value (ic50 ranges: 1.6-84.6 micrograms/ml or 2.6-137 microm). cl 118326 inhibits mammalian pancrea ... | 1993 | 8330926 |
| molecules and cognition: the latterday lessons of levels, language, and lac. evolutionary overview of brain structure and function in some vertebrates and invertebrates. | the characteristics of the nervous systems of a number of organisms in different phyla are examined at the recombinant dna, protein, neuroanatomic, neurophysiological, and cognitive levels. among the invertebrates, special attention is paid to the advantages as well as the shortcomings of the fly drosophila melanogaster, the worm caenorhabditis elegans, the honey bee apis mellifera, the sea hare aplysia californica, the octopus octopus vulgaris, and the squid loligo pealei. among vertebrates, th ... | 1993 | 8331341 |
| toxicity of the venom from nasonia vitripennis (hymenoptera: pteromalidae) toward fly hosts, nontarget insects, different developmental stages, and cultured insect cells. | a venom preparation from nasonia vitripennis, a wasp ectoparasitoid of fly pupae, was assayed for lethality in different stages of insects representing ten different orders and in cultured insect cells. in most cases, the motor activity of the injected insects remained completely normal for 1-2 days after the injection and displayed none of the symptoms of paralysis commonly reported for venoms of the hymenoptera. a natural host, the flesh fly sarcophaga bullata, was highly sensitive in the pupa ... | 1993 | 8342173 |
| influence of different signal peptides and prosequences on expression and secretion of human tissue plasminogen activator in the baculovirus system. | foreign secretory pathway proteins are often produced in surprisingly low amounts in the baculovirus/insect cell expression system. one possible reason for this is that heterologous signal peptides might be inefficiently recognized by the insect cell protein translocation machinery. this idea was supported by a recent study showing that secretion of a plant protein in the baculovirus system was enhanced when its signal peptide was replaced with an insect-derived signal peptide (tessier, d. c., t ... | 1993 | 8344955 |
| proteolytic processing of the vitellogenin precursor in the boll weevil, anthonomus grandis. | the soluble proteins of the eggs of the coleopteran insect anthonomus grandis boheman, the cotton boll weevil, consist almost entirely of two vitellin types with m(r)s of 160,000 and 47,000. we sequenced their n-terminal ends and one internal cyanogen bromide fragment of the large vitellin and compared these sequences with the deduced amino acid sequence from the vitellogenin gene. the results suggest that both the boll weevil vitellin proteins are products of the proteolytic cleavage of a singl ... | 1993 | 8347856 |
| inhibitory effect of caffeic acid esters on azoxymethane-induced biochemical changes and aberrant crypt foci formation in rat colon. | previous work from this laboratory established that caffeic acid esters, present in the propolis of honey bee hives, are potent inhibitors of human colon tumor cell growth, suggesting that these compounds may possess antitumor activity against colon carcinogenesis. the present study was designed to investigate (a) the inhibitory effects of methyl caffeate (mc) and phenylethyl caffeate (pec) on azoxymethane (aom)-induced ornithine decarboxylase (odc), tyrosine protein kinase (tpk), and arachidoni ... | 1993 | 8364913 |
| phospholipase a2 activity can protect renal tubules from oxygen deprivation injury. | during hypoxic or ischemic renal tubular injury, phospholipase a2 (pla2) induces membrane deacylation, causing fatty acid accumulation and phospholipid breakdown. because these changes can compromise cellular integrity, pla2 activity has been widely proposed as a critical mediator of hypoxic renal tubular injury and, hence, of ischemic acute renal failure. to explore this hypothesis, isolated rat proximal tubules were subjected to continuous oxygenation or to hypoxic injury with or without exoge ... | 1993 | 8367497 |
| stimulus-associated protein in gastric parietal cell detected using antimelittin antibody. | the bee venom polypeptide melittin binds to and inhibits the gastric hydrogen-potassium-adenosinetriphosphatase (h(+)-k(+)-atpase). a search for parietal cell proteins with a melittin-like structure was carried out. a 67-kda (doublet) protein, which reacted with a polyclonal antimelittin antibody, was found in purified rabbit parietal cells. the protein exhibited reversible stimulus-dependent redistribution from cytosol to (total) membranes. it was also found to be associated with h(+)-k(+)-atpa ... | 1993 | 8386462 |
| characterization of structural and functional phosphoinositide domains in human erythrocyte membranes. | in the erythrocyte membrane, only a fraction (50-60%) of phosphatidylinositol 4,5-bisphosphate (pip2) and of phosphatidylinositol 4-phosphate (pip) is rapidly turned over by specific kinases and phosphatases and accessible to hydrolysis by the polyphosphoinositide (ppi)-specific phospholipase c (plc). to investigate whether the metabolic segregation of ppi resulted from preferential interactions with proteins, we have measured the accessibility of ppi to bee venom phospholipase a2 (pla2) in nati ... | 1993 | 8389583 |
| role of the na+,k+ pump in herpes simplex type 1-induced cell fusion: melittin causes specific reversion of syncytial mutants with the syn1 mutation to syn+ (wild-type) phenotype. | to evaluate the importance of the na+,k+ pump and ionic gradients in virus-induced cell fusion, we investigated the effects of melittin, a 26 amino acid bioactive peptide found in honey bee venom, on cell fusion caused by hsv-1 syncytial mutants. melittin inhibited fusion of vero cells caused by hsv-1 mutant viruses mp(mp), kos (syn20) and kos (ffv3) containing the syncytial mutation syn1 in glycoprotein k. however, it did not affect cell fusion caused by mutants hfem(tsb5) or kos amb1511-7 with ... | 1993 | 8396802 |
| [comparison of anti-inflammatory, analgesic activities, anaphylactogenicity and acute toxicity between bee venom and its peptides]. | bee venom 1.0-2.0 mg/kg and bee venom peptides 1.0-2.0 mg/kg inhibited several inflammatory processes, such as ear swelling induced by xylene in mice, edema produced by injecting 1% carrageenin 0.1 ml beneath the plantar surface of hind paw in rats and showed a marked analgesic action induced by the hot plate and potassium antimony tartrate. bee venom peptides had a markedly more effective action as compared with bee venom itself. the anaphylactogenicity of bee venom peptides was apparently mild ... | 1993 | 8400773 |
| modulation of alpha 1-acid glycoprotein (agp) gene induction following honey bee venom administration to adjuvant arthritic (aa) rats; possible role of agp on aa development. | honey bee venom (hbv) administration to adjuvant arthritic (aa) rats resulted in a significant suppression of arthritis and in suppression of the hepatic acute phase alpha 1-acid glycoprotein (agp) gene induction at the early stages of disease development. agp administration in aa rats resulted in acceleration of arthritis development and in increase of severity and duration of the disease. il-1, il-6, tumour necrosis factor (tnf) and glucocorticoids alone are not responsible for the hbv-mediate ... | 1993 | 8403499 |
| stimulatory effect of phospholipase a2 treatment on glucose utilization in human erythrocytes. | we examined whether modification of membrane phospholipids of human erythrocytes by hydrolysis with phospholipase a2 (pla2 from bee venom) would affect glucose utilization, chosen as a typical model of intracellular metabolism, and, if so, intended to clarify the mechanism of the alteration of glycolysis. treatment of erythrocytes with pla2 induced a marked shape change (i.e., crenation) and significantly increased the rate of lactate production from glucose. available evidence indicated that th ... | 1993 | 8418896 |
| postmortem diagnosis of acute anaphylaxis by serum tryptase analysis. a case report. | systemic anaphylaxis is an acute allergic emergency resulting from generalized mast cell degranulation. in the united states, it is estimated that anaphylaxis accounts for about 500 deaths each year. hymenoptera-sting hypersensitivity is one of the most common causes of systemic anaphylaxis. the authors report a case of a healthy 26-year-old man who developed acute anaphylaxis after a bee sting, could not be resuscitated, and died within 1 hour. at autopsy, performed 14 hours after the event, th ... | 1993 | 8422006 |
| specificity of factor xa in the cleavage of fusion proteins. | the precursor protein honey bee prepromelittin has been expressed as a fusion protein in escherichia coli joined to the c-terminus of a truncated form of the bacteriophage gene 10 protein via an engineered recognition sequence for factor xa. factor xa was found to cleave poorly at the engineered site, giving a low yield of the required prepromelittin. in contrast, cleavage on the c-terminal side of the sequence vlgr at residue 67 in the gene 10 sequence proceeded in high yield. factor xa may be ... | 1993 | 8427626 |
| responses of purified phospholipases a2 to phospholipase a2 activating protein (plap) and melittin. | the role of the phospholipase a2 (pla2) stimulating protein plap in the regulation of pla2 activity was assessed by determination of the effects of plap on two purified pla2s. an approx. 14 kda enzyme was purified from mouse thymoma cells, el-4 cells, by cation ion exchange hplc and immunoaffinity hplc (with antiserum to the n-terminal sequence of an inflammatory exudate pla2). an approx. 110 kda enzyme was purified from mouse mammary carcinoma derived cells by sequential hydrophobic, anion exch ... | 1993 | 8431486 |
| melittin-induced hyperactivation of phospholipase a2 activity and calcium influx in ras-transformed cells. | the activated ras oncogene is a key mediator of cellular transformation and is present in a wide variety of primary human neoplasms. the biochemical role of the ras oncogene in cellular transformation is at present unclear, and hence approaches to control its activities in transformed cells have met with limited success. previous studies have demonstrated the ability of melittin, a 26 amino acid amphipathic peptide from bee venom, to specifically counterselect for cells in culture that express h ... | 1993 | 8455945 |
| functional and chemical characterization of hymenoptaecin, an antibacterial polypeptide that is infection-inducible in the honeybee (apis mellifera). | as part of our ongoing search for novel antimicrobial agents and their use in singular or combined drug therapy, we have isolated a series of polypeptides from the lymph fluid of honeybees. these polypeptides are synthesized de novo, following experimental infection of the insect with live escherichia coli cells, and confer a broad-spectrum antibacterial defense to the host. we have dissected this humoral "immune" system into its constituent components. in addition to the previously characterize ... | 1993 | 8463238 |
| apidaecin multipeptide precursor structure: a putative mechanism for amplification of the insect antibacterial response. | apidaecins are the most prominent components of the honeybee humoral defense against microbial invasion. our analysis of cdna clones indicated that up to 12 of these short peptides (2 kda) can be generated by processing of single precursor proteins; different isoforms are hereby linked in one promolecule. assembly of the multipeptide precursors and the putative three-step maturation are strongly reminiscent of yeast alpha-mating factor. bioactive apidaecins are flanked by the two 'processing' se ... | 1993 | 8467807 |
| cytochemical evidence for the presence of phospholipids in epithelial tight junction strands. | previous freeze-fracture experiments using either glutaraldehyde-fixed and cryoprotected specimens or unfixed rapid-frozen samples led to the proposal that cylindrical strands of the tight junction (tj) observed in freeze-fracture preparations are inverted cylindrical micelles made up of membrane lipids and, possibly, membrane proteins. however, no one has yet been able to directly label the structural fibrils of the tj. to test the hypothesis that tj strands observed on freeze-fracture preparat ... | 1993 | 8468446 |
| memory processing and apamin induce immediate early gene expression in mouse brain. | the present study analyses the effects of learning on the spatial pattern and the time-course of changes of immediate early gene messenger rna's (c-fos and c-jun) in mouse brain produced by training in an appetitive bar-pressing task. activation of c-fos and c-jun after training is strictly located in the hippocampal formation and is learning-dependent. levels of both proto-oncogene mrnas in the trained group were 4 to 5 times higher than in the sham-conditioned group. injections of apamin, a be ... | 1993 | 8479285 |
| elimination of ige regulatory rat cd8+ t cells in vivo differentially modulates interleukin-4 and interferon-gamma but not interleukin-2 production by splenic t cells. | intraperitoneal immunization of hooded lister rats with a soluble antigen such as bee venom phospholipase a2 (pla2), or ovalbumin (ova) together with the toxic lectin, ricin, eliminates a population of early-activated cd8+ t cells which regulate ige production. these early-activated cd8+ t cells are eliminated because they bear increased ricin-binding glycoproteins on their surface. this immunization regimen produces a vigorous and long-lived ige response. the effect of this treatment on the cap ... | 1993 | 8495968 |
| the impact of predators on livestock in the abruzzo region of italy. | free-living populations of wolves (canis lupus linnaeus, 1758) and brown bears (ursus arctos linnaeus, 1758) regularly cause damage to livestock in the abruzzo region of italy. the laws of the region provide for compensation payments to owners for losses caused by predators. in the present paper, 4,993 validated claims made between 1980 and 1988 are examined. losses ascribed to wolf, bear and wild boar attacks were 92.1%, 7.8% and 0.1%, respectively, of the total losses caused by predators durin ... | 1993 | 8518446 |
| the cultural production of bioterapia: psychic healing and the natural medicine movement in slovakia. | despite powerful opposition, natural medicine (nm) has achieved a toe-hold in the state-run biomedical system in the slovak republic. the physician-leader of the nm movement hopes to leverage his ministerial post as nm 'supreme expert' and his interlocking nm clinical and research facilities to achieve a complex, unified health care system under control of medical doctors. this health care model simultaneously reinforces biomedical hegemony and decenters classical medicine by substituting a bioe ... | 1995 | 8545679 |