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At least 55 records · Page 3Linked to original sources
PubMed1988

Color development upon reaction of ferric ion with the toxin JSTX, a glutamate receptor blocker present in the venom gland of the spider Nephila clavata (Joro spider).

A spider toxin, JSTX, derived from Nephila clavata, which blocks glutamate receptor was found to react with Fe3+. Mechanism of the coloration may be chelate formation since the green color completely faded upon the addition of EDTA. The colored JSTX significantly lost its neurophysiological activity. This unique coloration may be useful for not only detecting specific blockers of the glutamate receptor in spider venom but also for characterizing the glutamate receptor.

Animals↗
PubMed1977

The distribution of acetylcholinesterase in the central nervous system of jumping spiders and wolf spiders (Arachnida, Araneida: Salticidae et Lycosidae).

The distribution and activity pattern of acetylcholinesterase in the central nervous system of salticid and lycosid spiders has been studied. Enzyme activity was limited to the neuropile mass. The salticid and lycosid species investigated showed different intensities of enzyme reactions in the protocerebrum. The differences observed may be related to the somewhat contrasting habits of these spider families. Reactions were strong especially in the optic ganglia (lamina glomerularis, corpora pedunculata) and in the cerebral ganglion, while the central body showed only weak to moderate activity. In the cheliceral ganglia, as in the pedipalpal and the leg ganglia, including the fibre tracts of the ventral cord the demonstration of acetylcholinesterase was of moderate to strong intensity.

Acetylcholinesterase↗
PubMed2005

Female genital system of the folding-trapdoor spider Antrodiaetus unicolor (Hentz, 1842) (Antrodiaetidae, Araneae): ultrastructural study of form and function with notes on reproductive biology of spiders.

The genitalia of the female folding-trapdoor spider Antrodiaetus unicolor are characterized by two pairs of spermathecae that are arranged in a single row and connected to the roof of the bursa copulatrix. Each single spermatheca is divided into three main parts: stalk, bowl, and bulb, which are surrounded by the spermathecal gland. The epithelium of the spermathecal gland is underlain by a muscle meshwork and consists of different types of cells partly belonging to glandular cell units (Class 3 gland cells) that extend into pores in the cuticle of the stalk and bowl. Interestingly, the bulb lacks glandular pores and is characterized by a weakly sclerotized cuticle. This peculiarly structured bulb probably plays an important role in the discharge of the sperm mass. It is suggested that by contraction of the muscle layer the sperm mass may be squeezed out, when the bulb invaginates and expands into the spermathecal lumen, pushing the sperm to the uterus lumen. Each glandular unit consists of usually one or two central secretory cells that are for the most part surrounded by a connecting cell that again is surrounded by a canal cell. The canal cell, finally, is separated from the other epithelial cells (intercalary cells) located between the glandular units by several thin sheath cells that form the outer enveloping layer of the unit. The secretions are released through a cuticular duct that originates proximally between the apical part of the connecting cell and the apical microvilli of the secretory cells and runs into a pore of the spermathecal cuticle. The glandular products of the Class 3 gland cells likely contribute to the conditions allowing long-term storage of the spermatozoa in this species. Details regarding the ovary, the uterus internus, and the uterus externus are reported. Most of the secretion that composes the chorion of the egg is produced in the ovary. Glandular cell units observed in the uterus externus differ structurally from those in the spermathecae and likely play a different role. Finally, we briefly discuss our results on the female genitalia of A. unicolor in the light of knowledge about the reproductive biology of spiders.

Animals↗
PubMedDate not supplied

[Local dermonecrotic loxoscelism in children bitten by the spider Loxosceles reclusa (the "violin" spider)].

This is an observational retrospective study. Our goal is to describe the local dermonecrotic reaction occurring after a spider bite in eleven pediatric patients. In seven (63.7%), the spider was identified as Loxosceles reclusa, and in four, bites were presumptive. The main symptoms and signs were pain, erythema, swelling, blisters, and vasculitis in five patients. There was a significant relationship between the time of onset before the treatment and the severity of the lesions (63.4 hours in the severe cases vs 14.4 hours in the mild cases, p < 0.05), as well the time spent in the emergency room (50 hours vs 10 hours respectively, p < 0.05). Treatment with dapsone, 1 mg/kg/24 h, and/or paracetamol and dicloxacillin was successful; one case required surgical treatment. No systemic loxoscelism occurred in this patient.

Acetaminophen↗
PubMed1999

Circadian oscillation of sensitivity of spider eyes: diurnal and nocturnal spiders.

The circadian oscillation of sensitivity of the anterior median eye of a nocturnal spider Araneus ventricosus and that of a diurnal spider Menemerus confusus were examined by recording electroretinograms. The anterior median eye of Araneus ventricosus showed a marked circadian oscillation of sensitivity, but that of Menemerus confusus showed no circadian oscillation.

Journal Article↗
PubMed2004

The wonderful world of spiders: preface to the special Toxicon issue on spider venoms.

Spiders are remarkable for their complete reliance on predation as a trophic strategy. Their evolutionary success is due in large part to production of a complex venom that is designed to rapidly subdue or kill their prey. This issue provides an overview of the fascinating complexity of these venoms, a realistic account of the danger they pose to humans, and an examination of their immense but largely untapped potential for drug and insecticide discovery.

Animals↗
PubMed1998

Structures of spider toxins: hydroxyindole-3-acetylpolyamines and a new generalized structure of type-E compounds obtained from the venom of the Joro spider, Nephila clavata.

Facile structure determination of acylpolyamines, glutamatergic nerve blocker obtained from the venom of the Joro spider (Nephila clavata) was carried out with the use of micro-column LC/MS and high energy collision induced dissociation (CID) mass spectrometry. 6-hydroxyindole-3-acetyl was proposed previously as a putative partial structure, for the acyl moiety of hydroxyindole-type polyamines (NPTX-1 to -6). The NMR data obtained for NPTX-6, NPTX-687 and hydroxyindole-3-acetic acid which was released by acid hydrolysis of Nephila clavata crude venom extracts proved that the lipophilic head is the 4-hydroxyindole-3-acetic acid. Various hydroxyindole-3-acetyl polyamines were found in N. Clavata venom and characterized by mass spectrometry. As a result, type-E, a new class of generalized acylpolyamine structure was proposed in addition to the previously reported polyamine backbones type-A to -D.

Chromatography, Liquid↗
PubMedDate not supplied

The unique ribbon morphology of the major ampullate silk of spiders from the genus Loxosceles (recluse spiders).

The morphology of silk produced by recluse spiders (Loxosceles arizonica) was investigated by scanning electron microscopy, atomic force microscopy, and transmission electron microscopy. This silk consisted entirely of very long, thin ribbons of width 2-4 microm and thicknesses of no more than 40 nm. The correspondence in shape and dimension between the silk ribbons and the elongated aperture of the major ampullate spigot indicated that these ribbons were major ampullate silk. Selected area electron diffraction patterns from single ribbons were indexed with an orthorhombic unit cell (a = 9.43(2) A, b = 8.96(3) A, c = 6.96(1) A). This unit cell is in good agreement with that previously reported for synthetic poly(L-alanylglycine). Thus it is likely that the crystalline regions of the major ampullate silk of L. arizonica consist of an alternating glycine-L-alanine motif that has adopted a beta-sheet structure. The amino acid composition achieved with the silk of L. arizonica as well as that of L. laeta confirmed that the major amino acid constituents of this silk were glycine and L-alanine in nearly equal amounts. As it was noticed that the dry ribbons were highly electrostatic, it is suggested that the electrostatic interaction plays an important role in prey capture for Loxoseles.

Amino Acids↗
PubMed2000

Cues by which Portia fimbriata, an araneophagic jumping spider, distinguishes jumping-spider prey from other prey.

Portia fimbriata from Queensland, Australia, is an araneophagic jumping spider (Salticidae) that includes in its predatory strategy a tactic (cryptic stalking) enabling it to prey effectively on a wide range of salticids from other genera. Optical cues used by P. fimbriata to identify the salticid species on which it most commonly preys, Jacksonoides queenslandicus, were investigated experimentally in the laboratory using odorless lures made from dead prey on which various combinations of features were altered. P. fimbriata adopted cryptic stalking only against intact salticid lures and modified lures on which the large anterior-median eyes were visible. Ordinary stalking was usually adopted when the lure did not have the anterior-median eyes visible. There was no evidence that cues from the legs of prey salticids influence the choice of stalking style of P. fimbriata, but cues from the legs do appear to influence strongly whether a prey is stalked at all. Cues from the cephalothorax and abdomen also influenced the stalking tendency, but to a lesser degree than cues from the legs. An algorithm to describe the perceptual processes of P. fimbriata when visually discriminating between salticid and non-salticid prey is discussed.

Animals↗
PubMed1992

[Studies on the spiders as folk medicines (II). Species of the medicinal spiders in Japan].

In old Japanese literature of natural history, there were some descriptions on the medicinal spiders. We investigated these descriptions and could determine 14 groups as follows: 1. Latouchia typica, 2. Atypus karschi, 3. Loxosceles rufescens, 4. Achaearanea tepidariorum, 5. Araneus ventricosus, 6. Argiope amoena, 7. A bruennichii, 8. Nephila clavata, 9. Tetragnatha spp., 10. Uroctea compactilis, 11. Agelena limbata, 12. Tegenaria domestica, 13. Heteropoda venatoria, 14. Menemerus confusus and some species belonging to the family Salticidae.

Animals↗
PubMed2005

Induced production of extrafloral nectar in intact lima bean plants in response to volatiles from spider mite-infested conspecific plants as a possible indirect defense against spider mites.

We found that intact lima bean plants increased the secretion of extrafloral nectar (EFN) after exposure to Tetranychus urticae-induced plant volatiles. Predatory mites, Phytoseiulus persimilis, dispersed more slowly from an exposed intact plant than from a control plant (plant exposed to volatiles from intact conspecific). The predators also dispersed more slowly from those plants that were provided with extra EFN than from untreated plants. We further show that EFN was a potential alternative food source for P. persimilis. From these results, we concluded that increased EFN was involved in the slow dispersal of P. persimilis from the plants exposed to herbivore-induced plant volatiles. Our data suggest that the increase of EFN in an HIPV-exposed intact plant could be an induced indirect defense against spider mites.

Fabaceae↗
PubMed2004

Re-visioning the spider woman archetype in Kiss of the Spider Woman.

The article examines the transformation of spider woman archetype from Manuel Puig's adaptation of his novel to a play, and other adaptations into a film and a musical. The paper examines how the archetype's image and function shift when 're-visioned' by various artists and performed in disparate social contexts.

Humans↗