Includes bibliographical references. The venom from the Australian brown snakes (Pseudonaja spp.) contains a strong procoagulant component that produces bleeding due to consumption of clotting factors in bite victims. Investigation of the role of phospholipid and calcium found neither was essential for activity, but calcium could shorten the clotting time.

Cnidarians are the largest phylum of generally toxic animals, yet their toxins and venoms have not received as much scientific attention as those of many terrestrial (snakes, scorpions, spiders, etc.) and even some marine animals (i.e. cone snails). Approximately 13,000 living cnidarian species have been described by systematists. A major rationale for their study in the past, besides scientific curiousity, was to better treat victims of their envenomation. While that goal remains a high priority, it is now appreciated that the toxins of these mostly marine animals can be very useful molecular probes for the analysis of ion channels involved in electrical signaling, immune responses and other signal transduction processes of biomedical interest. For instance, anaphylaxis was discovered by Richet (1905) during experiments with sea anemone and hydrozoan tentacular extracts. Similarly, it has recently been shown that a toxin from another sea anemone is able to potently inhibit T-lymphocyte proliferation in models of certain autoimmune diseases. Thus, these natural substances continue to be of relevance for understanding and treating human diseases. In addition to introducing phylum Cnidaria (Coelenterata), we provide a short history of early (until about 1990) research on cnidarian toxins and venoms, to provide a perspective for appreciating the scientific advances of the past two decades that are summarized in the ensuing 19 papers in this special Toxicon issue.

In this investigation, venom from the giant Neotropical hunting ant Dinoponera australis (Order: Hymenoptera) has been harvested and subjected to chromatographic separations for the purpose of elucidating possible peptides that display neuroactivity by bioassay guided venom fractionation (BGVF). The venom of this arcane solitary predator paralyzes small invertebrate prey and causes highly exaggerated pain in large vertebrates. The hypothesis that the venom has a peptide component highly effective in modulating neuronal conduction by depolarization of cellular membranes has been tested and subsequent biochemical characterization has been performed to elucidate the primary structure. The data suggests that the modulation of neuronal conduction appears to result from the formation of a de novo pore that allows non-selective ion movements in a concentration dependent manner. The venom contains a variety of proteinaceous candidates and one particular peptide from the venom, -Dinoponeratoxin Da-1837, has been observed to cause very fast, large and sustained depolarization in two types of normally quiescent peripheral neurons (primary cultures of trigeminal and dorsal root ganglia) in whole cell patch clamp recordings. The profound depolarization is due to non-selective cationic flux which is irreversible at high concentrations. Preliminary studies suggest that the peptide also has a minor inhibitory effect on voltage-gated sodium channels, which does not contribute to the depolarization. Membrane assays with microsomes, fluorescent probes and lipid bilayers confirmed peptide-induced non-selective and concentration dependent permeabilization of the membrane. The primary structure of the peptide was determined by iterations of product ion scans in multiple configurations utilizing high resolution tandem mass spectrometry, commonly referred to as MS-MS data dependent acquisition. -DpTx Da-1837 is an eighteen residue peptide that is highly hydrophobic, positively charged at physiological pH and has one atypical post translational modification, i.e. C-terminal peptidyl-lysine. The authentication of the toxin was confirmed by the successful solid phase synthesis of an analog that showed neither biochemical nor physiological variation from the properties of the peptide isolated from Dinoponera australis. The conclusion of this study was the creation of derivative analogs that provide the platform for the first fundamental step in drug discovery: establishing the structure-function relationship. Although the purpose of these cytolytic peptides in venom may be to capture prey or discourage predation, the discoveries of new molecules that affect cell viability by interactions with the cellular envelope provide the genesis for studies of targeted cell death. As a novel anti-microbial agent or as a potent tumor suppressor, the development of peptide derivatives could also help direct the development of new therapeutic interventions.

Thesis (M.Tech.: Homoeopathy) -Dept. of Homoeopathy, Durban Institute of Technology, 2004 1 v. (various pagings) / The purpose of this investigation was to determine the effects of the thirtieth centesimal (30CH) potency of the venom of Bitis gabonica gabonica on healthy individuals in order to elucidate the total morbid symptomatology produced by the drug so that it may be prescribed by Homoeopathic practitioners according to the Law of Similars, as is required by Homoeopathic methodology. It was hypothesized that the 30CH potency of Bitis gabonica gabonica would produce clearly observable signs and symptoms in healthy Provers.

Mini-dissertation submitted in partial compliance with the requirements of the Master’s Degree in Technology: Homoeopathy in the Faculty of Health Sciences at the Durban University of Technology, 2008. / The aim of this study was to elicit and document the effects, in the form of signs and symptoms produced in relatively healthy volunteers, of the venom of Hemachatus haemachatus, prepared in accordance with the methods set out in the homoeopathic pharmacopoeia. These signs and symptoms form the indications for the prescription of the remedy, according to the homoeopathic Law of Similars. A further aim of this study was a comparative analysis of symptoms produced by Hemachatus haemachatus 30ch with existing remedies derived from snake venom used in homeopathy, with the aim of highlighting the similarities and differences between them. The homoeopathic drug proving of Hemachatus haemachatus 30ch took the form of a double-blind, placebo controlled trial. The proving population consisted of 30 healthy subjects who met with the necessary inclusion criteria (Appendix B). Eighty percent (24 subjects) served as the experimental group, receiving the active verum in a randomised manner, while twenty percent (6 subjects) formed the placebo group, receiving non-medicated placebo powders in a randomised manner. Provers were unaware of either the nature or potency of the substance. Verum and placebo were indistinguishable from each other, and neither researcher nor volunteers knew who received verum and who received placebo. Intra-individual control was achieved through a pre-proving observation period of a week’s duration, during which provers recorded the signs and symptoms of their normal state. This symptom picture served as a baseline for comparison with symptoms noted after administration of the remedy. Verum and placebo were dispensed in the form of six powders to be taken sublingually three times a day for a period of two days, or until the onset of symptoms. Data was primarily collected in the form of a diary or journal kept by each prover in which they recorded symptoms on a daily basis. Provers were closely monitored by the researchers during this period. Data collected by the researchers during daily telephonic contacts, as well as during the pre-proving consultation, was also considered. Information obtained from the journals was then assessed by the researchers for suitability for inclusion in the materia medica of Hemachatus haemachatus. The data did not require statistical analysis. In a concurrent study of similar methodology, Cahill (2008) conducted a comparison of the symptom complex produced in the proving of Hemachatus haemachatus, with other homeopathic remedies which scored highest on repertorisation. Symptoms from both studies were collated and included in the materia medica and repertory of Hemachatus haemachatus. The investigation supported the hypothesis that Hemachatus haemachatus would produce clear and observable signs and symptoms in healthy proving volunteers. During the course of this study provers experienced a wide range of mental, emotional and physical symptoms. The highest number of symptoms was produced on the mental and emotional level. Provers experienced elation, joy, increased confidence, enthusiasm and energy. On the other hand, there was lack of confidence, vulnerability, anxiety, decreased motivation, decreased concentration, lethargy, depression and indifference. There were sudden changes in mood and provers experienced marked irritability. On the physical level, many provers experienced headaches, irritation of the eyes, symptoms resembling allergic rhinitis, sore throats, nausea, heartburn, abdominal pain and flatulence, menstrual disturbances, lumbar pain, rheumatic joint pains, and skin eruptions. There were disturbances in normal sleep patterns, subjective perceptions of increased body temperature with hot flushes, and generalised tiredness and lethargy. Symptoms obtained from the proving of Hemachatus haemachatus were analysed as part of a comparative study with other remedies derived from snake venom: Lachesis muta, Naja tripudians, Elaps corallinus, Naja mossambica and Bitis arietans arietans. This comparison highlighted both the similarities and differences between these remedies and Hemachatus haemachatus. / M

No description available.

No description available.

Cone snails are predatory marine animals that rely on their venom components to immobilize and capture their prey. According to the type of prey preference, cone snails can be divided into three groups: vermivorous, molluscivorous and piscivorous. Conus ermineus had been identified as the only piscivorous snail of the Atlantic Ocean. Cone snail venom is a complex and rich sources of natural toxins. The majority of the components of the venom are peptidic in nature, and they act over different ionic channels and membrane receptors. Initial studies using mixture of venom collected from dissected venom ducts concluded that the venom from the same species do not exhibit unusual peptide polymorphism [Olivera, Hillyard, et al., 1995] and that the only major difference between individuals of the same species are different concentrations of the venom components [Vianna, et al., 2005]. For this study, peptides in the injected venom were collected from individual snails and characterized usin g analytical RP-HPLC for a maximum of three years. The different fractions collected were processed through capillary HPLC coupled with Q-TOF ESI-MS, and compared with analytical RP-HPLC fractions processed with MALDI-TOF MS. This study demonstrates that there is an animal-to-animal variation in the peptide components of the injected venom. The injected venom remains relatively constant over time for specific specimens in captivity. Finally, there are some peptides that had been found in all specimens both by MALDI-TOF MS and by ESI-MS. In this study, these peptides are called "molecular fingerprint" peptides. Based on matches of their derived masses to those predicted by published cDNA sequences, nine novel peptides were putatively identified. This study establishes that variations due to enzymatic posttranslational modification are omitted when we consider only information extrapolated from cDNA. / The results of this study support the idea of the existence of a novel regulatory mechaism to expressed specific venom peptides for injection into the prey. / by Jose A. Rivera-Ortiz. / Thesis (Ph.D.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.

The venom of marine gastropods belonging to the genus Conus has yielded numerous structurally and functionally diverse peptidic components. The increase variety of bioactive peptides identified in cone snail venoms is the product of the variety of molecular adaptations taken by Conus species in evolving neuroactive molecules to suit their diverse biological purposes. Toxins from cone snails are classified into two major groups. One group consists of disulfide-rich peptides commonly termed conotoxins; the second group comprises peptides with only one disulfide bond or none. In this work, we present the discovery and characterization from the marine snails C. planorbis and C. ferrugineus. Both species are commonly found in the Indo-Pacific region and are very similar and is not distinguishable by size and shape of the shell. Novel P and T-Supefamiles were found in both species along with small linear peptides with have a high frequency of tyrosine residues. Each chapter contains a detailed look at the discovery process for the isolation and characterization of C. planorbis and C. ferrugineus. At discussion part, we also compared the peptides isolated in this work with other peptides from the literature. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

Thesis (M. Ph.)--Chinese University of Hong Kong. / Bibliography: l. 73-78.