Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Spiders”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 433 records · Page 24Linked to original sources
PubMed1997

Pulsed dye laser treatment of spider telangiectasia.

Spider telangiectasia is a common benign vascular malformation which can be a source of cosmetic concern for the patient. A retrospective review of 30 adults and children with spider telangiectasia treated by the flashlamp-pumped pulsed dye laser was undertaken. There was complete clearance of treated spider telangiectasia in 93% of patients after a single treatment. There were no reported permanent adverse effects with purpura being the only transient problem. Most patients were satisfied with the eventual results of treatment and would recommend treatment to other people with a similar problem. This laser should be considered as the treatment of choice for spider telangiectasia.

Adolescent↗
PubMed2002

Plant-related factors influence the effectiveness of Neoseiulus fallacis (Acari: Phytoseiidae), a biological control agent of spider mites on landscape ornamental plants.

The predatory mite Neoseiulus fallacis (Garman) was evaluated as a biological control agent of herbivorous mites on outdoor-grown ornamental landscape plants. To elucidate factors that may affect predator efficiency, replicated tests were conducted on 30 ornamental plant cultivars that varied in relationship to their generalized morphology (e.g., conifers, shade trees, evergreen shrubs, deciduous shrubs, and herbaceous perennials), production method (potted or field grown), canopy density, and the prey species present on each. Plant morphological grouping and foliar density appeared to be the most influential factors in predicting successful biological control. Among plant morphological groups, N. fallacis was most effective on shrubs and herbaceous perennials and less effective on conifers and shade trees. N. fallacis was equally effective at controlling spider mites on containerized (potted) and field grown plants, and there was no difference in control of mites on plants with Tetranychus spp. versus those with Oligonychus or Schizotetranychus spp. Moderate to unsuccessful control of spider mites by N. fallacis occurred mostly on tall, vertical plants with sparse canopies. Acceptable spider mite control occurred in four large-scale releases of N. fallacis into production plantings of Abies procera, Thuja occidentalis 'Emerald', Malus rootstock, and Viburnum plicatum 'Newport'. These data suggest that N. fallacis can be an effective biological control agent of multiple spider mite species in a range of low-growing and selected higher growing ornamental plants.

Acari↗
PubMed2005

Within-plant distribution of twospotted spider mites (Acari: Tetranychidae) on impatiens: development of a presence-absence sampling plan.

The twospotted spider mite, Tetranychus urticae Koch, is an important pest of impatiens, a floricultural crop of increasing economic importance in the United States. The large amount of foliage on individual impatiens plants, the small size of mites, and their ability to quickly build high populations make a reliable sampling method essential when developing a pest management program. In our study, we were particularly interested in using spider mite counts as a basis for releasing biological control agents. The within-plant distribution of mites was established in greenhouse experiments and these data were used to identify the sampling unit. Leaves were divided into three zones according to location on the plant: inner, intermediate, and other. On average, 40, 33, and 27% of the leaves belonged to the inner, intermediate, and other leaf zones, respectively. However, because 60% of the mites consistently were found on the intermediate leaves, intermediate leaves were chosen as the sampling unit. These results lead to the development of a presence-absence sampling method for T. urticae by using Taylor coefficients generic for this pest. The accuracy of this method was verified against an independent data set. By determining numerical or binomial sample sizes for consistently estimating twospotted spider mite populations, growers will now be able to determine the number of predatory mites that should be released to control twospotted spider mites on impatiens.

Animals↗
PubMed1997

Preliminary Study on the Primary Structure of Dragline Fibroin from the Spider Araneus ventrocosus.

The amino acid composition of the dragline fibroin from the spider fibroin of the spider Araneus ventrocosus was analysed and compared with that of the fibroins from different species of spiders. By means of partial acid hydrolysis and high performance liquid chromatography, several peptide fragments of the dragline fibroin were purified. The amino acid sequence analysis showed the sequences of these peptides to be different from that of the fibroin from the spider Nephila clavipes except for one common fragment with the sequence of GYGPG.

Journal Article↗
PubMed2005

Spider Screw: skeletal anchorage system.

The stability of the anchorage unit plays a very important role in orthodontic control. Controlled orthodontic movements such as retraction and/or protraction of teeth and intrusion of overerupted teeth are very difficult to achieve without patient cooperation and without causing undesirable reciprocal movement in the anchorage unit. The article describes characteristics, surgical procedure, and clinical use of the Spider Screw as an ideal non-dental and non-cooperation based anchorage system. The Spider Screws are self-tapping, titanium mini-screws with immediate loading capability. Their utilization involves a simple biomechanical principle combined with the utilization of minimum orthodontic mechanotherapy. Ideal orthodontic forces (in the range from 50 to 250 gr) can be applied to achieve the desired orthodontic movements. Complete osteointegration is neither expected nor desired with this anchorage system. The Spider Screw anchorage system can be used to support a variety of orthodontic movements specifically in clinical situations involving incomplete dental arches and limited cooperation as in many adult orthodontic cases. The ease of surgical placement combined with the reduced dimension of the Spider Screw diameter equally permits its use in clinical situations where anchorage recovery is necessary during treatment of complete dentitions in classical orthodontic therapy.

Adult↗
PubMed2005

The SPIDER Embolic Protection Device performance evaluation in the carotid artery during percutaneous transluminal angioplasty and or stenting.

Recently completed studies have compared carotid endarterectomy with carotid artery stenting, a nonsurgical method of improving blood flow in the carotid arteries. Embolic protection devices can prevent particles dislodged during carotid artery stenting from causing stroke or death. An ev3 Inc.-sponsored trial (PROTECT) evaluated the performance requirements of the SPIDER Embolic Protection Device in the carotid artery for CE Marking. Patients who were candidates for percutaneous transluminal angioplasty (PTA) and or stenting were enrolled. Performance was assessed by determining the incidence of major adverse neurological events (MANE) through 30 days post-procedure in 74 patients, along with the successful placement and recovery rates of the filter. MANE was defined as stroke or death. There were a total of 5 MANE events reported in 5 patients, 1 major stroke and 4 minor strokes. There were no deaths. The total MANE event rate was 6.8% (5 of 73). The overall SAE rate was 8.2% (6 of 73). An SAE was defined as an event that resulted in the hospitalization or prolongation of hospitalization due to potential disability, or due to danger of life that resulted in an intervention or that was terminal. Technical success of the SPIDER device was defined as placement of the filter at the distal edge of the lesion in the carotid artery, placement of the recovery catheter and successful retrieval of the filter with the recovery catheter. An inability to place or retrieve the filter was concluded to be a system failure. The SPIDER device was successfully placed in the carotid artery and retrieved with an overall successful placement rate of 88.1% (74 of 84), and a retrieval rate of 98.6% (73 of 74). In conclusion, the PROTECT Trial demonstrated that the performance of the SPIDER device in the carotid artery complied with the relevant Product Directives for CE Marking. The incidence of MANE was low and comparable to what has been reported in recently published literature.

Aged↗
PubMed1993

[Unilateral "nevoid" spider nevi].

A case of unilateral spider telangiectasia on the left side of the face initiating at puberty is reported. With respect to its therapy and prognosis this alteration must be distinguished from other telangiectasias. With unilateral nevoid telangiectasia it shares the unilateral distribution of the lesions and the predilection for the female sex during hormonal instability periods. Both of these types of acquired telangiectasia seem to occur in relation with endocrine influences. Unilateral nevoid telangiectasia may also show typical spider telangiectasia but occurs in combination with other telangiectatic alterations. Unilateral "nevoid" spider telangiectasia consists exclusively of spider telangiectasia. Pathogenesis and further differential diagnosis of this peculiar type of primary telangiectasia are outlined.

Adolescent↗
PubMed2004

Structure determination of an organometallic 1-(diazenylaryl)ethanol: a novel toxin subclass from the web of the spider Nephila clavipes.

A novel chemical subclass of toxin, [1-(3-diazenylphenyl)ethanol]iron, was identified among the compounds present in the web of the spider Nephila clavipes. This type of compound is not common among natural products, mainly in spider-venom toxins; it was shown to be a potent paralytic and/or lethal toxin applied by the spider over its web to ensure prey capture only by topical application. The structure was elucidated by means of ESI mass spectrometry, 1H-NMR spectroscopy, high-resolution (HR) mass spectrometry, and ICP spectrometry. The structure of [1-(3-diazenylphenyl)ethanol]iron and the study of its insecticidal action may be used as a starting point for the development of new drugs for pest control in agriculture.

Animals↗
PubMed2002

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and high-performance liquid chromatography study of quantitative and qualitative variation in tarantula spider venoms.

Animal venoms are important sources of novel pharmacological tools, useful in biochemical characterization of their receptors. Venom quality control, batch-to-batch homogeneity and high reproducibility of venom fractionation and toxin purification are crucial issues for biochemical and pharmacological studies. To address these issues, a study of the variability of tarantula spider venom samples was undertaken. Venom profiles of samples collected from individuals of different age and sex, and from sibling spiders of the same species, were generated by high-performance liquid chromatography (HPLC) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and analyzed to assess venom variability and method accuracy. Sex-linked venom variation was studied on eight species. Clear qualitative differences were observed for six out of eight species, as well as quantitative differences. Age-related variation studied in Poecilotheria rufilata showed essentially age-related quantitative differences between adults of both sexes and immature juveniles. The venoms of nine siblings and three wild-collected Pterinochilus murinus were studied for individual variation, showing only very minor quantitative differences. On the same samples, the quality of MALDI-TOFMS venom fingerprinting was demonstrated to be highly reproducible. Our results show that tarantula venom peptide fingerprinting is a highly reliable identification method, that pooled batches of venom from several animals can be used for venom purification, that venom composition does not appear to be qualitatively related to ontogenesis in the spiders studied, and that qualitative sex-linked variation occurs across most species and may be important in activity studies.

Aging↗
PubMed2003

Isolation and characterization of hainantoxin-IV, a novel antagonist of tetrodotoxin-sensitive sodium channels from the Chinese bird spider Selenocosmia hainana.

A neurotoxin, named hainantoxin-IV, was purified from the venom of the spider Selenocosmia hainana. The amino acid sequence was determined by Edman degradation, revealing it to be a 35-residue polypeptide amidated at its C terminal and including three disulfide bridges: Cys2-Cys17, Cys9-Cys24, and Cys16-Cys31 assigned by partial reduction and sequence analysis. Hainantoxin-IV shares 80% sequence identity with huwentoxin-IV from the spider S. huwena, a potent antagonist that acts at site 1 on tetrodotoxin-sensitive (TTX-S) sodium channels, suggesting that hainantoxin-IV adopts an inhibitor cystine knot structural motif like huwentoin-IV. Under whole-cell voltage-clamp conditions, this toxin has no effect on tetrodotoxin-resistant voltage-gated sodium channels in adult rat dorsal root ganglion neurons, while it blocks TTX-S sodium channels in a manner similar to huwentoxin-IV, and the actions of both toxins on sodium currents are very similar to that of tetrodotoxin. Thus, they define a new family of spider toxins affecting sodium channels.

Amino Acid Sequence↗
PubMed2000

Immunocytochemical localization and secretion process of the toxin CSTX-1 in the venom gland of the wandering spider Cupiennius salei (Araneae: Ctenidae).

Fluorescein and horseradish peroxidase-labeled monoclonal antibodies were used to localize the predominant toxic peptide CSTX-1 in the venom gland of the spider Cupiennius salei. There was no polarity of CSTX-1 expression in repleted glands, whereas the glands of previously milked spiders showed a decreasing immunofluorescent response from the distal to the proximal portion. Detailed investigation revealed a new structure in the venom-secreting epithelium, which is postulated to be an evolutionary adaptation to increasing gland volume. CSTX-1 was found to be synthesized and stored as a fully active toxin within complex units, composed of long interdigitating cells running perpendicular to the muscular sheath and extending into the central lumen of the gland. These venom-producing units were found in all sectors of the gland, including the transitional region between the main gland and the venom duct. The venom is liberated from the venom-producing units into the glandular lumen following the contraction of the surrounding muscle layer. Free nuclei or other cellular fragments, which would have provided evidence for a holocrine secretion process, were not found in the glandular lumen or in the crude venom obtained by electrical stimulation. The fine regulation of the spider's venom injection process is postulated to be the function of the bulbous ampulla, situated in the anterior third of the venom duct.

Adaptation, Physiological↗
PubMed2005

Case report: compartment syndrome after a suspected black widow spider bite.

Widow spider envenomations generally produce systemic neurologic syndromes without significant local injury. We report a patient who sustained a black widow spider bite to the left forearm and presented to the emergency department with rhabdomyolysis and compartment syndrome. We documented a decrease in symptoms and compartment pressure after administration of antivenom. No surgical intervention was performed. We believe this report to be the first documenting compartment syndrome associated with black widow spider bite.

Animals↗
PubMed2026

Sex- and development-specific transcriptomic profiling of venom and silk genes in the wolf spider Pardosa astrigera provides insights into ecological adaptation and predatory strategies.

Spider venom and silk glands are two major secretory systems that contribute to prey capture, defense, and reproduction, but their sex- and development-specific molecular regulation in wandering wolf spiders remains poorly understood. Here, the transcriptome of Pardosa astrigera, an important agricultural natural enemy in China, revealed significant sex- and development-associated molecular differentiation among adult females, adult males, and spiderlings. A total of 100,025 unigenes were obtained, of which 23,852 were functionally annotated, providing a comprehensive transcriptomic resource for this species. Differential expression patterns showed marked variation among groups, with 531, 1792, and 832 DEGs detected in PAF vs PAS, PAM vs PAS, and PAF vs PAM, respectively. These genes were mainly associated with metabolic, oxidation-reduction, cuticle development, MAPK signaling, and lysosome pathways. Fifteen co-expression modules revealed distinct expression patterns. The turquoise, pink, yellow, and red modules were development-related, whereas the blue module was male-biased. Venom- and spidroin-related genes were distributed across multiple modules, suggesting coordinated regulation. Overall, 42 venom peptides, 21 venom proteins, and 11 spidroins were identified. Representative genes showed strongly biased expression, including spiderling-biased U3_Pp1a and U5_Pp1e, female-biased U4_Pp1a, and male-biased SMase D_108750 and PaTuSp_108466. These findings reveal sex- and development-biased expression patterns of venom- and silk-related candidate genes in P. astrigera and may provide molecular insights into ecological adaptation and predatory strategies in wandering wolf spiders.

Animals↗
PubMed2005

Enzymatic characterization, antigenic cross-reactivity and neutralization of dermonecrotic activity of five Loxosceles spider venoms of medical importance in the Americas.

Loxosceles spiders have a wide distribution in the temperate and tropical regions of the world. Loxoscelism is characterized by necrotic skin ulceration at the bite site and, less commonly, a systemic illness that may be fatal. The purpose of this study was to characterize and compare aspects of the major medically important Loxosceles spider venoms in a standardized manner, particularly considering their neutralization by two Brazilian antivenoms. By SDS-PAGE (12% acrylamide), Loxosceles deserta, Loxosceles gaucho, Loxosceles intermedia, Loxosceles laeta and Loxosceles reclusa venoms had similar electrophoretic profiles, with the major protein bands of 32-35 kDa. All venoms exhibited gelatinolytic, caseinolytic and fibrinogenolytic activities in vitro with a large array of proteases, mainly between 18.1 and 31.8 kDa. Most of these enzymes were metalloproteases as this activity was abolished by 1,10-phenanthroline. Hyaluronidase activity was detected in a protein band of approximately 44 kDa in all venoms. Sphingomyelinase activity was demonstrated in all five venoms. Antigenic cross-reactivity, by Western blotting, was also observed among all venoms studied using commercial equine antivenoms produced in Brazil (Institute Butantan and CPPI). These antivenoms recognized mainly components between 25 and 40 kDa in all venoms with several minor components of >89 kDa. Strong cross-reactivity was also seen among all venoms through the ELISA technique (titre range: 64,000-512,000). All venoms (5 microg doses) induced a similar local reaction when injected intradermally into the flank of rabbits, demonstrating dermonecrosis, hemorrhage, vasoconstriction, edema, and erythema. However, no reaction was observed when each venom was pre-incubated (1 h, 37 degrees C) with Brazilian commercial sera prior to injection. The antivenoms also abolished the sphingomyelinase activity in vitro, suggesting the venoms of the major medically important Loxosceles spider species have generally similar toxic and enzymatic characteristics. Thus, as Brazilian commercial antivenoms are able to neutralize the dermonecrosis induced by Loxosceles venoms of diverse geographical origin, clinical studies should be undertaken on the potential for a single global Loxosceles antivenom.

Animals↗
PubMed2005

Characterization of the venom from the Brazilian Brown Spider Loxosceles similis Moenkhaus, 1898 (Araneae, Sicariidae).

Accidents caused by brown spiders (Loxosceles genus) are frequent in Brazil and are associated with dermonecrotic lesions and, eventually, systemic reactions that may be lethal. The major species implicated with human envenoming have been: L. intermedia, L. gaucho and L. laeta. In this study we characterized the venom from Loxosceles similis, a species of spider normally found inside caves. L. similis venom was characterized by two-dimensional gel electrophoresis and enzymatic activity (dermonecrosis and haemolysis). The lethal dose to mice and the capacity of commercial anti-serum to neutralize this venom were also analysed. The cross-reactivity with anti-venoms against L. intermedia, L. laeta and L. gaucho were studied. Our results showed that this venom was able to induce severe dermonecrotic lesions and showed the presence of the bacteria Clostridium septicum in association with the fangs. In addition, we have cloned the DNA coding for a dermonecrotic protein (LsD1), using the genomic DNA of L. similis. The deduced amino acid sequence showed a toxin of approximately 31.2 kDa with an estimated pI of 7.37 and sequence similar to LiD1, a protein from the dermonecrotic family of Loxosceles intermedia spider venom, a synanthropic species of medical importance.

Animals↗
PubMed2006

Verified bites by the woodlouse spider, Dysdera crocata.

Bites by the woodlouse spider, Dysdera crocata, are virtually innocuous. The main symptom is minor pain, typically lasting less than 1h, probably due mostly to mechanical puncture of the skin. However, because the spider has a strong proclivity to bite, has large fangs which it bares when threatened and is commonly mistaken for the medically important brown recluse spider in the United States, documentation of the mild effects of its bites may prevent excessive, unwarranted and possibly harmful treatment. We present information on eight verified bites reported to us as well as eight additional bites recorded in the literature.

Adolescent↗
PubMed2002

Novel insecticidal toxins from the venom of the spider Segestria florentina.

Three insecticidal polypeptide toxins (F5.5, F5.6, F5.7) with molecular masses 4973, 4993 and 5159Da were isolated from the venom of the central Asian spider Segestria florentina. These toxins caused the complete flaccid paralysis of Heliothis virescens (Lepidoptera: Noctuidae) larvae (LD(50) 4-10 microg/g), whereas they were inactive upon intravenous injections into mice. On the basis of N-terminal amino acid sequences a family of eight genes encoding highly homologues polypeptides (SFI1-SFI8) was revealed, some of which encode polypeptides actually demonstrated to be present in S. florentina venom. All deduced polypeptides consist of 46 amino acids residues. Comparison of primary structures of SFI1-SFI8 with other spider toxins suggests that this family might share structural and functional relationships with other small spider neurotoxins, several of which are known to be highly selective agonists/antagonists of different voltage-dependent Ca(2+) channels.

Amino Acid Sequence↗