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At least 19 recordsLinked to original sources
PubMed1992

[Transcatheter embolization for huge pulmonary arteriovenous fistula using metallic "spider" and spring embolus--application of hand-made metallic "spider" using partial monorail technique].

We performed transcatheter embolization in two cases with huge pulmonary arteriovenous fistula (AVF) using a metallic "spider" and spring embolus. Conventional spring embolus or detachable balloon could not be used in these cases. Metallic spider was indicated for pulmonary AVF with a feeding artery diameter of more than 16 mm to prevent embolus passing through the AVF. In the first case, we used large handmade metallic spiders of 25 mm in diameter followed by embolization by numerous spring coils. At that time, a partial monorail technique was newly devised to carry the large metallic spider into the feeding artery, otherwise the spider could not pass into a 9F catheter. After embolization, symptoms and PaO2 in arterial blood improved remarkably in both cases. In the second case, a spring coil migrated into the normal pulmonary artery, but no infarction resulted. In conclusion, the metallic spider was very useful for embolization of hugee pulmonary AVF to avoid the embolus passing through and to tangle spring coils together with it. If commercially available "spiders" are too small, ones can be made easily.

Adult↗
PubMed1990

Spiders and spider bites.

The only spiders of real medical importance to humans in the United States are the Loxosceles and Latrodectus species, primarily the brown recluse and the black window, respectively. These spiders bite humans only when trapped or crushed against the skin. Severe brown recluse spider bites produce dermonecrosis within 72-96 hours, which should be treated with rest, ice compresses, antibiotics, dapsone, and surgery delayed for several weeks. Using systemic corticosteroids may be helpful in treating the much rarer systemic loxoscelism, which has minimal skin changes but produces massive hemolysis. Black widow bites do not produce marked skin changes but primarily produce muscle cramping, pain, and other neuromuscular-related symptoms. Though a specific antivenin for black widow bites is available, pain control, muscle relaxants, and calcium gluconate are generally adequate treatment. Many other spiders inflict painful bites, but arachnids do not medically deserve the bad reputation that they generally have with the public.

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↗
PubMed1977

Action of brown widow spider venom and botulinum toxin on the frog neuromuscular junction examined with the freeze-fracture technique.

1. Structural changes which normally accompany transmitter release at frog neuromuscular junctions are visualized with the freeze-fracture technique. The effects of brown widow spider venom and botulinum toxin were evaluated in terms of their ability to block or produce these structural changes. Changes produced by these neuropoisons were correlated with their known effects on neurotransmitter release. 3. Fusion of synaptic vesicles with the presynaptic plasmalemma, normally evoked by electrical stimulation, was abolished at neuromuscular junctions from frogs treated with botulinum toxin. 3. The concentration of large intramembranous particles in the presynaptic plasmalemma, an indication of the excess of synaptic vesicle fusion over recovery of synaptic vesicle membrane, was increased by treatment with brown widow spider venom, even in the presence of botulinum toxin. 4. When external calcium was present, sites of vesicle fusion induced by brown widow spider venom, as well as by electrical stimulation, were located mainly in the active zone. In the absence of external calcium, many plasmalemmal deformations, also though to be sites of vesicle fusion, were more evenly dispersed over the presynaptic surface of nerve terminals. 5. Botulinum toxin decreased the number of vesicle fusion sites in the active zone induced by spider venom in the presence of external calcium but had little effect on the number of fusion sites induced by spider venom in the absence of external calcium. 6. Nerve terminals soaked in a sodium-free Ringer solution were partially depleted of vesicles. Addition of spider venom to this Ringer did not cause additional depletion of vesicles. 7. Formation of cation-permeable channels in the presynaptic membrane could account for these effects of spider venom on the frog neuromuscular junction. Botulinum toxin blocks vesicle fusion by some means which is not yet understood.

Animals↗
PubMed1992

Clinical presentation and treatment of black widow spider envenomation: a review of 163 cases.

STUDY OBJECTIVE: To review cases of black widow spider envenomation to describe the clinical presentation and evaluate the efficacy of treatment. DESIGN: Retrospective chart review. SETTING: An urban toxicology referral center. TYPE OF PARTICIPANTS: All patients attended by the toxicology service and discharged from our hospital between January 1982 and December 1990 with a diagnosis of black widow spider envenomation. INTERVENTIONS: Inclusion criteria were either a positive black widow spider identification or a visible envenomation site ("target lesion"). Depending on the clinical presentation, patients were categorized as grade 1, 2, or 3 in severity. The efficacy and side effects of treatment alternative were evaluated. MEASUREMENTS AND MAIN RESULTS: One hundred sixty-three patients met the inclusion criteria. The most common sites of envenomation were the upper and lower extremities. The most common presenting complaint was generalized abdominal, back, and leg pain. One hundred eighteen patients initially presented to our institution, and 45 were transfers. Pain relief of grade 2 and 3 envenomations was achieved most effectively with either black widow spider-specific antivenin alone or a combination of IV opioids and muscle relaxants. Fifty-eight patients received antivenin with complete resolution of symptoms in a mean time of 31 +/- 26.7 minutes. Of the 118 patients initially seen at our institution, the mean total duration of symptoms was 9 +/- 22.7 hours in patients receiving antivenin and 22 +/- 24.9 hours in patients not receiving antivenin. Fifty-two percent of patients not receiving antivenin required hospitalization, whereas only 12% of those receiving antivenin were admitted. One patient died of severe bronchospasm after receiving antivenin. Calcium gluconate was not effective in providing symptomatic relief in this series, with 96% of the grade 2 and 3 envenomations treated initially with calcium gluconate requiring the addition of IV opioids or other analgesics for symptomatic relief. Fifty-five percent of patients initially receiving IV morphine and 70% of those initially receiving both IV morphine and benzodiazepines obtained symptomatic relief without additional medication. CONCLUSION: One hundred sixty-three envenomations by black widow spiders were reviewed and graded according to severity with treatment modalities evaluated. Although calcium gluconate usually has been considered the first-line treatment of severe envenomations by black widow spiders, we found it ineffective for pain relief compared with a combination of IV opioids and benzodiazepines. The use of antivenin significantly shortened the duration of symptoms in severe envenomations.

Adolescent↗
PubMed1975

[Role of the principal and accessory eyes in the photomenotactic orientation of the funnel spider Agelena labyrinthica (CL.)].

The photomenotactic orientation of funnel spiders (Agelena labyrinthica [Cl.]) returning to their retreat was studied by measuring the direction of their course on the horizontal webs. 1. If a lamp was shifted 90 degrees just before the spider caught its prey the mean return course deviated less than 90 degrees from the direction of the retreat. This deviation was not only a function of the azimuth of the light and of the amount it had been moved, but also varied with the course taken when approaching the prey, the duration of the interval without light stimulation while the lamps were changed, the light stimulation experienced while at the retreat, the extent to which vision was experimentally reduced, and the light intensity. 2. Elimination of the principal or of the accessory eyes had little or no significant effect on the photomenotactic orientation. Spiders able to use only the median eye or one principal eye could no longer use the lamp to orient by. 3. Animals with full vision showed an increased (decreased) deviation from the direction of the retreat if the light intensity was abruptly increased (decreased), as did animals without principal eyes or without accessory eyes. The mean return directions were, however, not dependent upon light intensity changes before reaching the prey or after an interruption of web contact. The threshold for photomenotactic orientation using the accessory eyes is 0.366-10(-4) sb; the corresponding value for the principal eyes is 100 times larger. 4. If the lamp was not visible on the outward run the spiders were unable to perform correct return runs by light orientation without optical information from previous runs. If they could see a lamp while at the retreat their return course was shifted in the direction away from the light. Animals without principal eyes did not show this effect. 5. Spiders that had not performed an outward run did not keep to a straight course. Animals with full vision spontaneously showed negative phototactic orientation, those without principal eyes were usually positively phototactic. 6. Animals, whose web contact had been interrupted or animals without principal eyes showed a similar deviation from the correct return direction as did unmanipulated animals.

Animals↗
PubMed1986

Channels produced by spider venoms in bilayer lipid membrane: mechanisms of ion transport and toxic action.

The selectivity of ion channels produced by latrotoxin obtained from a black widow spider venom and by venom from the spider Steatoda paykulliana in bilayer phospholipid membrane was studied. Experimental current-voltage curves of these channels were used for the estimation of parameters of a two barrier model of their energy profiles. Selectivities of both types of channels are similar. Alkaline earth cations are permeable, the permeability increasing in the order Mg2+ less than Ca2+ less than Sr2+ less than Ba2+. In contrast transition metal cations block the channel, their efficiency decreases in the order: Cd2+ greater than or equal to Ni2+ greater than Zn2+ greater than Co2+ greater than Mn2+ (Steatoda paykulliana spider venom) and Cd2+ greater than Co2+ greater than Ni2+ greater than Zn2+ greater than Mn2+ (latrotoxin). Amplitudes of current carried by corresponding ions are mainly determined by the depth of the potential well for this ion, i.e., by its affinity to the cation binding site in the channel. The channels are also permeable to monovalent cations but they do not bind them. Selectivity for monovalent cations depends on Ca2+ concentration at the cis-side of membrane in the micromolar range. However, the addition of Ca2+ to the trans-side up to 10 mM does not affect currents carried by monovalent ions. It is suggested that venom-induced calcium channels have two conformational states with different selectivities which interconvert upon binding one calcium ion. Possible general schemes for the organisation of calcium channels in excitable membranes are also discussed. Finally, using a mathematical model of synaptic transmission, possible mechanisms of toxic action of spider venoms are considered.

Animals↗
PubMed1977

Quantitative analysis of orb web patterns in four species of spiders.

The orb webs of the four species Araneus pima (species nova), Araneus diadematus (Clerck), Argiope aurantia (Lucas), and Neoscona domiciliorum (Hentz) built under controlled laboratory conditions were compared and evaluated quantitatively at two different points in the life cycle in regard to size, regularity, shape, and fine structure. Orb webs of two species from one genus can be distinguished, but are more alike than webs from different genera. Mature spiders built highly specific webs, a fact which may play a role in species isolation during courtship. In adults, web measures correlated in size with the spiders' taxon; young spiders' web size measurements corresponded rather to their body weight or leg length. A web's regularity seemed to be closely related to age. Adult and young spiders built oval-shaped webs with eccentric hubs. Mesh width was correlated with leg length at both age levels. Web data support the likelihood of a monophyletic evolution of the four species.

Age Factors↗
PubMed1991

Imagery ability and exposure in vivo in spider phobia.

The present study deals with the effect of imagery ability on treatment outcome in spider phobias. Thirty-eight spider phobics completed the Questionnaire on Mental Imagery (QMI) and the Spider Questionnaire (SPQ). Subjects also went through a behavioral approach task (BAT) during which heart rate and avoidance behavior were measured. Each subject was then given one-session treatment as described by Ost. Immediately after treatment, SPQ and BAT data were again obtained. On the basis of their QMI scores, subjects were assigned to a 'good', 'moderate', or 'poor' imagers group. Neither pre-treatment nor post-treatment measures were found to vary as a function of imagery ability. Thus it appears that, at least for specific phobias such as spider fear, imagery ability is not a relevant variable for predicting the effects of in vivo exposure.

Adolescent↗
PubMed1991

Covariation bias and electrodermal responding in spider phobics before and after behavioural treatment.

The present study investigated whether a covariation bias is present in severe spider phobics and whether such bias is modified by successful treatment. In addition, this study sought to examine whether a covariation bias is linked to differential autonomic responding. Subjects were 20 untreated phobics, 19 treated phobics, and 18 no-fear controls. Subjects were exposed to a series of 72 slides comprising three categories: spiders (fear-relevant), mushrooms, and flowers. At slide offset one of three possible outcomes occurred: a shock, a tone, or nothing at all. All slide-outcome combinations occurred equally frequent. The results show that an equally strong covariation bias is present in severe spider phobics, in successfully treated phobics, and in no-fear controls. Thus, the present data only partially sustain earlier findings of Tomarken, A. J., Mineka, S. & Cook, M. (1989) (Journal of Abnormal Psychology, 98, 381-394). The covariation bias appeared to be mimicked by differentially heightened autonomic responding. The current data suggest that both the covariation bias and the heightened physiological responding reflect a "beloningness" between spider slides and aversive outcome.

Adolescent↗
PubMed1989

Zinc ion enhances the blocking potency of synthetic analogs of spider toxin (JSTX) on the glutamate receptor.

The effect of synthetic spider toxin analogs containing aza-crown in combination with zinc and copper was studied on the lobster neuromuscular synapse. The suppressive action of N4-type spider toxin analog (N4) on excitatory postsynaptic potentials (EPSPs) was markedly enhanced in the presence of 10(-5)-10(-4) M Zn2+. Cu2+ (10(-4) M) also had a potentiating effect on the suppression of EPSPs by N4 but to a lesser degree than Zn2+. While N6-type spider toxin analog (N6) suppressed EPSPs more effectively than N4, additional suppression was not pronounced in the presence of Zn2+ or Cu2+. The results suggest that chelatable divalent metal ions play an important role in the blocking mechanism of glutamate receptor by the spider toxin.

Action Potentials↗
PubMed1991

Chemical attraction of kleptoparasitic flies to heteropteran insects caught by orb-weaving spiders.

Insects of the heteropteran families Pentatomidae (stink bugs) and Coreidae (squash bugs), when being eaten by the orb-weaving spider Nephila clavipes, attract flies of the family Milichiidae. The flies aggregate on the bugs and, as kleptoparasites, share in the spider's meal. Stink bugs and squash bugs typically eject defensive sprays when attacked; they do so when caught by Nephila, but the spray only minimally affects the spider. Evidence is presented indicating that it is the spray of the bugs that attracts milichiids to the spider's catch.

Aldehydes↗
PubMed1975

[Basic analysis of the effective system of homing in spider Agelena labyrinthica (Cl.)].

1. The spider Agelena labyrinthica Cl. determined its home direction by integrating the information of each element of the outgoing path to the prey in continuous interaction with the incident light. 2. A vector hypothesis explaining how the direction and the length of the homing track was determined was verified: if the azimuth of the incident light was displaced by 90 degrees as soon as the spider had reached a certain point on the web, the vector of the theoretical course originating from this point was rotated by about 60 degrees. The end point of this rotated vector ("fictitious retreat point") was not only the goal for the homing course from this point, but also for the course originating from any other point of the web. 3. Spiders starting at the fictitious retreat point did not keep straight courses. Their movements were either at random or they were directed in slightly preferred directions caused by the phototactic influence of the previously performed outward course. 4. If the light had been displaced before the spider was lifted from the web, the lifting had no effect on the orientation performance. 5. The mean distance between the points of direction changes and the starting points varied linearly with the mean length of the outward course; therefore these distances were used as an indication for the distance orientation. 6. Contrary to all other formerly published hypotheses on the photomenotactic orientation of arthropods MITTELSTAEDTs' hypothesis about the homing of Agelena, which is similar to my vector hypothesis, is compatible with the data compiled by this investigation.

Animals↗
PubMed1992

Cuticular spinning structures reveal evolutionary relationships in araneomorph spiders.

The present paper reviews the results from the study of spigots, i.e. cuticular spinning structures obtained by the scanning of 52 genera belonging to 28 families of araneomorph spiders. The finding of eight morphologically different forms of these structures being attached to ducts of the pyriform type of silk glands is of fundamental importance for the final conclusions. The comparative observations enable me to create a hypothesis dealing with the existence of several evolutionary lines of spiders, each of which is represented with their own form of spigots. Nevertheless the character of these spigots undoubtedly reflects phylogenetic relationships between the spider taxa. The detection of a special mechanoreceptive field on top of the anterolateral spinnerets increases the knowledge of the functional morphology of the spider's spinning apparatus.

Animals↗
PubMed1989

[Histochemical detection of enzymes in the spinning glands of spiders].

The spider's spinning apparatus equipped with numerous glands of several types appears to be a suitable model for studying tissues which produce large amounts of fibrillar proteins. Heterogeneous glandular system is of special benefit for study of the function of different enzymes taking part both in the synthesis and the degradation of mentioned proteins. It is evident that the activity of the enzyme is dependent not only on the physiologic condition or a certain phase of spider's life cycle, but it is also given by the type of gland, i. e., defined by the structure and properties of protein to be emitted. Histochemical study of enzymes brings some new and more precise views on the spinning apparatus function. Also a participation of individual gland types in some definite spider's life period is so indicated as well as it is convenient for better understanding biologic function of structures performed by spider.

Animals↗
PubMed1979

Inactivation of complement by Loxosceles reclusa spider venom.

Zymosan depletion of serum complement in guinea pigs rendered them highly resistant to lesion by Loxosceles reclusa spider venom. Guinea pigs deficient in C4 of the complement system are as sensitive to the venom as normal guinea pigs. The injection of 35 micrograms of whole recluse venom intradermally into guinea pigs lowered their complement level by 35.7%. Brown recluse spider venom in concentrations as slight as 0.02 micrograms protein/ml can totally inactivate one CH50 of guinea pig complement in vitro. Bee, scorpion, and other spider venoms had no influence on the hemolytic titer of complement. Fractionation of recluse spider venom by Sephadex G-200 filtration separated the complement-inactivating property of the venom into three major regions which could be distinguished on the basis of heat stability as well as size. None was neutralized by antivenom. Polyacrylamide gel electrophoresis of venom resolved the complement inactivators into five fractions. Complement inactivated by whole venom or the Sephadex fractions could be restored to hemolytic activity by supplements of fresh serum but not by heat-inactivated serum, pure C3, pure C5, or C3 and C5 in combination.

Animals↗