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PubMed2001

The widow spider Latrodectus tredecimguttatus: source of the remedy Tarentula hispanica?

The European wolf spider, Lycosa tarentula, said to have caused the historical phenomenon of 'tarantism', is the official medicinal source of the homeopathic remedy Tarentula hispanica. Yet, scientific evidence links the spider's venomous effects with mild necrotic and minor systemic effects that contrast with the proving symptoms of Tarentula hispanica which show a cerebral and neural component. A comparative investigation by use of toxicological, clinical findings, supported by modern and antique biological texts, as well as homeopathic materia medica, traces the source of the remedy Tarentula hispanica to the Mediterranean widow spider Latrodectus tredecimguttatus, thus warranting a re-evaluation of pharmacological preparation.

Animals↗
PubMed1992

Heterodimeric structure of the spider toxin omega-agatoxin IA revealed by precursor analysis and mass spectrometry.

We report the first molecular characterization of a precursor sequence for a small, Ca2+ channel blocking, peptide spider toxin, omega-agatoxin IA. By integrating information generated from a molecular genetic approach using agatoxin cDNAs with data provided from mass spectrometry of the mature toxin, we were able to deduce the likely mechanisms by which the toxin precursor peptide is processed to its mature heterodimeric form. A particularly interesting feature of the prepropeptide is the occurrence of two glutamate-rich sequences interposed between the signal sequences, the major peptide toxin, and the minor toxin peptide. Excision of the more distal glutamate-rich region appears to be signaled by flanking arginine residues but likely occurs only after a disulfide linkage has formed between the major and minor chains of the mature toxin. Our molecular genetic approach toward characterizing this toxin will allow us to quickly generate a series of spider sequences from which mature toxin structures can be deduced and eventually expressed. Additionally, this approach will provide insights into the evolutionary divergence observed among spider peptide toxins.

Agatoxins↗
PubMed2003

[The black widow spider--its appearance and control].

Between 1995 and 2002, a massive appearance of black widow (Latrodectus mactans tredecimguttatus, Rossi 1790) was recorded along the Croatia coast. This paper gives a historical review of latrodectism and observations from Istria and Dalmatia, paying particular attention to the spider's habitat. There are several reasons for the black widow to appear in a new habitat such as the introduction of leguminous plants, watermelons and melons where crops were grown earlier. Black widow can also be found near buildings and gardens. Human contacts with the spider are usually without consequences for humans, thanks to education and a relatively good visibility of the spider. The authors describe their experience in fighting black widow and emphasise the importance of education in preventing lactrodectism.

Animals↗
PubMed2004

Brown recluse spider bites to the head: three cases and a review.

Consequences of envenomation from the bite of a brown recluse spider (Loxosceles reclusa) range from mild itching to death. The bite of this spider causes the most severe form of arthropod-induced tissue necrosis. These bites pose several challenges to the clinician in that diagnosis can be difficult, systemic manifestations can occur, and healing can be resistant to conventional measures. Bites to the head and neck-particularly the face-are uncommon, and they have not been widely reported in the otolaryngology literature. As experts in facial soft tissue, otolaryngologists and facial plastic surgeons should be able to recognize and treat these lesions. Because no laboratory test is available to identify the cause of symptoms in these cases, the diagnosis is made clinically. Early intervention can make a significant difference in cosmetic outcome, so a high index of suspicion is warranted. Local wound care includes rest, ice, compression, and elevation of the affected part of the body. Drug therapy with dapsone may limit the severity of the bite and prevent complications. Because some bites cause systemic loxoscelism, clinicians should be familiar with its manifestations. When necrosis occurs despite adequate medical treatment, reconstructive procedures should be delayed until healing is complete. We report 3 cases of brown recluse spider bites to the head. These cases illustrate the broad spectrum of the disease course, and they highlight the therapeutic challenges that these lesions pose.

Female↗
PubMed2005

[Total upper lip necrosis and loxoscelism caused by violin spider bite].

Arthropods and in particular spiders are a common embodiment of our fears, despite the fact that only a few species are dangerous to man. The authors present a case involving severe local and general reactions to a loxosceles (brown recluse spider) bite. They give an overview of the occurrence of loxosceles spiders, the signs and symptoms of envenomation and the therapeutic possibilities. The severe symptoms presenting following loxosceles envenomation is termed loxoscelism. Loxoscelism is characterised by local soft tissue necrosis of varying degree at the site of the sting, and rarely, life-threatening general reactions, such as haemolysis with ensuing anaemia, and renal failure. Therapeutic interventions following loxosceles bites range from dapsone treatment to hyperbaric oxygen therapy, but the most promising therapy is the use of the antiserum, commercially available in certain South-American countries where loxosceles bites are common. Treatment of soft tissue necrosis consists of necrectomy and surgical reconstruction following the resolution of the inflammatory symptoms.

Aged↗
PubMedDate not supplied

[Poisoning caused by Latrodectus Mactans (Black Widow) spider bite among children. Clinical features and therapy].

INTRODUCTION: Poisoning caused by "black widow" spider bite, is not commonly observed during childhood, it is not exempt from complications, and must be treated in time or the patient can die. In Mexico we do not have accurate data on the exact number of accidents due to this condition. OBJECTIVE: Identify the signs and characteristic symptoms of children treated at the Children's Hospital from the state of Sonora with the aim of starting early treatment. MATERIAL AND METHODS: We reviewed 43 clinical records of hospitalized patients admitted for "black widow " spider bite between 1978 - 2004. Demographic variables were: age, gender, place of origin, place where accident took place, treatment given prior to hospital admittance, degree of envenomation measured by signs and symptoms, treatment and clinical evolution. RESULTS: 69.7% of cases were male, we did not find differences in the number of patients between infant, pre-school, elementary school children and teenagers. During summer and afternoon hours we registered 44% and 37% cases respectively; 74% patients were poisoned by the spider at home; the anatomical areas most affected were: arms, hands and thorax. Signs and symptoms in infants were: irritability, constanty cry, sialorrea, agitation erythema on wounded areas and seizures. Among elementary school children and teenagers signs included pain in wounded area, abdominal and thoracic, muscle spasms, fine tremor and residual signs. Patients who received fabotherapic treatment had better evolution and less time of hospitalization. No deaths were reported. CONCLUSIONS: The different signs and symptoms between infants, preschool, elementary school children and teenagers allowed us to clearly identify evenommation and differentiate it form confounding diseases. In our study, specific fabotherapy constituted the best treatment choice.

Adolescent↗
PubMed1980

Cutaneous necrosis caused by the bite of Chiracanthium spiders.

Spiders of the genus Chiracanthium are very common in and about homes in southern Africa. The bite of this spider results in cutaneous necrosis. The clinical and histopathological features and the natural history and identification of these spiders are discussed briefly.

Animals↗
PubMed1993

Passive hemagglutination inhibition test for diagnosis of brown recluse spider bite envenomation.

Our goal was to recreate a passive hemagglutination inhibition (PHAI) test to diagnose brown recluse spider (BRS; Loxosceles reclusa) bite envenomation for treatment trials. Guinea pigs received intradermal injections of concentrated spider venom from the following species: Loxosceles reclusa, Argiope aurantia, Argiope trifasciata, Phidippus audax, and Lycosa frondicola. Skin lesion exudate was collected and tested with the BRS venom PHAI assay. From 51 separate collections of exudate, test sensitivity was 90% as long as 3 days after venom injection. Specificity was 100% with venom from the other spider species listed above in vivo (7 test samples) and in vitro (5 test samples), as well as with random bacterial exudate with and without added serial dilutions of BRS venom (10 test samples). The test was reproducible over repetitive assays to within one 10-fold dilution. A positive PHAI test result could function as an entry criterion for BRS bite victims in human treatment trials.

Animals↗
PubMed1996

[Black widow spider (Latrodectus tredecimguttatus) bite. Presentation of 12 cases].

The most severe cases of arachnidism are those due to Latrodectus tredecimguttatus spider-bite. The Mediterranean area is the habitat of the L. tredecimguttatus species. In the last few years no series of patients with latrodectism has been reported in Spain. A retrospective study of the patients admitted for L. tredecimguttatus spider bite in the Torrecárdenas Hospital in Almeria, Spain from 1984 to 1994 was performed. Twelve patients were diagnosed with latrodectism. Eleven were bitten while carrying out agricultural tasks, 8 of which were performed in greenhouses. The mean time between the bite and the appearance of the general symptoms was 40 minutes (20-120 minutes), with the most common signs and symptoms being: pain and abdominal stiffness (10 cases), erythema (10 cases) or pain (8 cases) at the site of the bite, thoracic pain, pain in extremities and contractures and psychomotor alterations (6 cases). Laboratory findings were limited to leukocytosis (4 cases), increase in creatinphosphokinase count (4 cases) and proteinuria (3 cases). All the patients received analgesics, 6 were administered myorelaxants and calcium gluconate was given in 6 cases. The evolution was good without complications in all of the patients. Latrodectism is a rare phenomenon Spain. The diagnosis is difficult when there is absence of a clear history of spider bite and due to the lack of knowledge as to its semiology. Antivenom serum is not usually required.

Adolescent↗
PubMed1996

Danger expectancies and insight in spider phobia.

Differences between phobic and normal subject perceptions of danger were examined. Nineteen spider-fearful subjects and a matched set of controls gave danger ratings before and during a spider-avoidance test. When detached from the phobic stimulus, spider-fearful subjects: (1) gave higher estimates of the probability of being bitten than did controls, (2) gave higher estimates of the injuries that would result from being bitten, and (3) believed their high levels of anticipated anxiety were more reasonable and appropriate to the demands of the situation than did controls. These findings are inconsistent with both the traditional account and Beck and Emery's (1985) more recent view that, when detached from the phobic situation, patients can accurately evaluate the danger of potential phobic encounters. The present results question the view that phobic individuals have complete insight into the inappropriateness of their own distress.

Adaptation, Psychological↗
PubMed2002

Efferent innervation of photoreceptors in spiders.

The anterior median (AM) eye of the nocturnal spider Araneus ventricosus showed a marked circadian oscillation of sensitivity, but that of the diurnal spider Menemerus confusus showed no circadian oscillation. The AM eyes of the noct/diurnal spiders Argiope amoena and A. bruennichii have two types of photoreceptor cells with different sensitivities. The more sensitive cells showed a circadian oscillation of sensitivity, but the less sensitive cells did not. The circadian sensitivity change of the eyes was controlled by efferent neurosecretory fibers in the optic nerve. Illuminating the brain increased the frequency of efferent impulses in the optic nerve of Argiope, showing that certain photosensitive neurons are present in the brain. However, it seemed that the cerebral photosensitive neurons may be different from the efferent neurosecretory cells. The response of the cerebral photosensitive neurons increased transiently following diminution of the light intensity striking the eyes. The interaction between the cerebral photosensitive neurons and the eyes seemed to play a role in increasing this response.

Animals↗
PubMed2006

Impact of cypermethrin on feeding behaviour and mortality of the spider Pardosa amentata in arenas with artificial 'vegetation'.

Pesticides can modify invertebrate movement and feeding behaviour which could reduce predation in agroecosystems. Previous assays have exposed the spider Pardosa amentata (Clerck) to the synthetic pyrethroid cypermethrin and monitored prey items consumed in small containers (requiring very little movement to capture prey). The current study used larger arenas containing artificial 'vegetation' (a plastic analogue) to encourage spiders to hunt and capture prey. The period 24 h after exposure produced greatest variability in prey item consumption between treatments and was used to examine treatment effects. At this time, cypermethrin reduced prey consumption rates but these effects did not persist. Findings did not suggest that the presence of artificial vegetation in arenas modified prey consumption rates, which was consistent for individuals treated with cypermethrin and a control group. This is despite the majority of pesticide-treated individuals exhibiting both ataxia and paralysis of the hind legs (these effects persisting for a maximum of 3 and 6 days respectively). These findings were consistent for both sexes. Spider longevity under starvation conditions was not significantly reduced by cypermethrin exposure but overall females survived longer than males. The findings are discussed in the context of the arenas used and the ecology of this common predator.

Animals↗
PubMed2001

The effect of the herbicide glyphosate on non-target spiders: Part II. Indirect effects on Lepthyphantes tenuis in field margins.

We have examined the indirect effect of the herbicide glyphosate on the spider Lepthyphantes tenuis in field margins. Glyphosate was applied to a randomised block design field experiment comprising 360, 720 and 1440 g glyphosate AE ha-1 treatments and an unsprayed control. Spiders were sampled in each month from June to October 1998. Spider abundance was significantly lower in all the treatments than in the unsprayed control. Abundance was also significantly lower in the 720 and 1440 g treatments than in the 360 g treatment. No significant difference could be detected between the 720 and 1440 g treatments. Poisson regression models showed that patterns of decline in L tenuis were related to increasing dead vegetation and decreasing vegetation height. Glyphosate applications only had a within-season indirect habitat effect on L tenuis as field margins sprayed 16 months after an application of 360 g glyphosate ha-1 showed no detrimental effect.

Agriculture↗
PubMed1991

Arylamine spider toxins antagonize NMDA receptor-mediated synaptic transmission in rat hippocampal slices.

The effects of arylamine spider toxins on synaptic transmission in rat hippocampal slices were investigated. Two different responses were monitored: the AMPA receptor-mediated population spike recorded in control buffer (selectively antagonized by DNQX) and the NMDA receptor-mediated EPSP recorded in nominally magnesium-free buffer containing 20 microM DNQX (selectively antagonized by AP5, AP7, and dizocilpine (MK-801)). The synthetic arylamine spider toxins JSTX-3, argiotoxin-636, and argiotoxin-659 were 26 to 73 times more potent at antagonizing the NMDA receptor-mediated EPSP (IC50 values ranging from 12 to 24 microM) than the AMPA receptor-mediated population spike (IC50 values ranging from 612 to 878 microM). These results indicate that arylamine spider toxins are selective antagonists of NMDA receptors in the mammalian CNS.

Animals↗
PubMed1993

Effects of the pyrethroid insecticide Cypermethrin on the locomotor activity of the wolf spider Pardosa amentata: quantitative analysis employing computer-automated video tracking.

Wildlife in areas surrounding arable land is almost inevitably exposed to pesticide spray. Even at doses far below the lethal level, this presents a threat to vulnerable species. The widely used pyrethroid insecticides, including Cypermethrin, are known for their direct effect on the locomotor apparatus of animals, inducing varying degrees of paresis. Quantitative measurements of the voluntary locomotion of animals express an integrated response to changes in biochemical and physiological processes. In the present study, the effect of Cypermethrin on the voluntary locomotion of the wolf spider Pardosa amentata was quantified in an open field setup, using computer-automated video tracking. Each spider was recorded for 24 hr prior to pesticide exposure. After topical application of 4.6 ng of Cypermethrin, the animal was recorded for a further 48 hr. Finally, after 9 days of recovery, the spider was tracked for 24 hr. Initially, Cypermethrin induced an almost instant paralysis of the hind legs and a lack of coordination in movement seen in the jagged and circular track appearance. This phase culminated in total quiescence, lasting approximately 12 hr in males and 24-48 hr in females. Following paresis, the effects of Cypermethrin were evident in reduced path length, average velocity, and maximum velocity and an increase in the time spent in quiescence. Also, the pyrethroid disrupted the consistent distributions of walking velocity and periods of quiescence seen prior to pesticide application. Our results suggest that normal locomotion had returned 9 days after Cypermethrin application, but that recovery of high velocities was still incomplete.

Animals↗
PubMed2002

Evolution of spider silk proteins: insight from phylogenetic analyses.

Spider silks have astounding mechanical properties. In fact, dragline silk has greater tensile strength than commonly used synthetic materials such as nylon filament and capture spiral silk is among the most elastic protein known. The recent cloning of spider silk genes has revealed that silk proteins are composed of tandem arrayed ensembles of a small number of amino-acid sequence motifs. These repetitive motifs form the structural modules within silk fibers, and ae critical for determining the mechanical attributes of the silk. In this chapter, I examine the evolution of these motifs in the 11 published spider silk gene sequences. Extensive rearrangements of the motifs have occurred among the orthologous and paralogous proteins. Phylogenetic analyses suggest that numerous length mutations and recombination events have taken place in orthologous genes from closely related species and even within sets of alleles from the same species. Such genetic events appear to be critical for the homogenization of amino acid repeats within the silk proteins. The characterization of additional silk genes will clarify the relationships among novel amino acid motifs, the homogenization of motifs within a protein, and the function of silk fibers.

Amino Acid Sequence↗
PubMed1979

Phosphatases in the central nervous system of spiders (Arachnida, Araneae).

The central nervous systems of web-building spiders (Araneidae, Agelenidae) and hunting spiders (Lycosidae, Salticidae) were tested for non-specific and specific phosphatases. Acid phosphatase exhibited weakly to moderately positive reactions in the neuronal cell bodies and in the neuropile fibre mass of all species investigated. Alkaline phosphatase could only be demonstrated in the external and internal neural lamellae of the brain and ventral cord of several specimens of the araneid species investigated. Tests for thiamine pyrophosphatase were negative with both the lead and calcium-cobalt methods. Distinctive positive reactions for adenosine triphosphatase were visible in the nervous system of all the species used, being especially strong in the optic ganglia of the hunting spiders. The demonstration of adenosine triphosphatase was only possible when applying the calcium-cobalt method after Padykula and Herman, while the lead method after Wachstein and Meisel did not produce any staining reaction at all. Controls of the histochemical reaction showed that the enzyme was activated by Ca2+ and inhibited by sulphydryl destroying reagents (e.g. PCMB), but was insensitive to ouabain. It could be probably classified as a mitochondrial proton-translocating adenosine triphosphatase.

Acid Phosphatase↗
PubMed1991

The toxic effect of deltamethrin on linyphiid and erigonid spiders in connection with ambient temperature, humidity, and predation.

The first part of this study concerns the effect of temperature and air humidity on the toxicity of deltamethrin to the erigonid Oedothorax apicatus. The second part concerns the effect of deltamethrin on behavior of linyphiids and erigonids with respect to their ability to escape from predators and to select between unfavorable (dry) and favorable (moist) habitat conditions. The toxic effect of deltamethrin was highest at the combination of high temperature and low air humidity. It was concluded that the spider's sensitivity to drought is increased by this pyrethroid. Affected spiders, however, are less able to select moist habitat conditions than unaffected ones. Walking speed of spiders was decreased by exposure to deltamethrin and their predation by carabid beetles was increased. It was concluded that the effect observed under field conditions is the result of a combination of neurological, physiological, and behavioral disturbance.

Animals↗