Conotoxins, are exocrine toxic peptides from the epithelial cells of the cone gastraopodavenom duct which, for hunting and defense are synthesized. Conotoxins, are neurotoxins or cytotoxin. Neurotoxins, are agents of the pain reliever in animal models and cytotoxin usually introduced as factors of the anti-tumor. Hemolytic activity of the conotoxins extractions of two species CONUScoronatus and CONUSfrigidus tested. Sampling was done in Zeiton Park, Qeshm Island. The venom ducts were isolated and then homogenized. The mixture centrifuged at 10000 × g for 5 min. Supernatant was considered as extracted venom. Peptides up and down 10 kDa, were isolated by the filter Falcon MWCO 10000 Millipore. Serial concentrations of crude conotoxin extracts, essences top and bottom 10 kDa were used to examine the hemolytic activity in 96-well plates on human and fish red blood cells. Hemolytic activity of crude and essences up and down 10 kDa were different and only on human blood, hemolytical effects were observed. Crude extracts, in low concentrations, have no hemolytic activity and at a concentration of 1, 000 micrograms per milliliter, the percentage of hemolytic on human blood, was the species 62% and 38% on C. coronatus and C. frigidus, respectively. The extracts top 10 kDa has more hemolytic effects than the extracts less than 10 kDa. The effects of hemolytic of conotoxin extracts is different according to blood type and cytotoxin activities of the extracts were in high concentrations, so cause the presence of peptide neurotoxins pain in these species, they can use in drugs since are not led to damage on red blood cells.

Background: Cone snails are a natural source of complex peptides with analgesic properties called conotoxins. These peptides are secreted in a complex venomic mixture and are predominantly smaller than 5 kDa. The present study aimed to document the analgesic activity of two species of CONUS coronatus (C. coronatus) and CONUS frigidus (C. frigidus) venom collected off the Iranian coast in a mouse behavioral test. Methods: Conotoxin containing fractions was extracted from the venom ducts and initially purified by column chromatography. The analgesic effect of the fractions was determined on formalin pain model and hot-plate test. Results: The results led to the identification of four fractions with analgesic activity in C. coronatus and two in C. frigidus. Only one fraction was able to reduce the flinching and licking in both acute pain and chronic pain phases of the formalin test. Moreover, the activity of this fraction remained 30 minutes on the hot-plate test. Purification of the fractions was carried out by RP-HPLC. LC-ESI-MS analysis of the fractions showed that the conotoxins of the analgesic fraction had molecular weights not previously reported. Conclusion: The findings give insight into the venom of two previously under-investigated CONUS species and reveal the therapeutic potential of the containing conopeptides.

Background and Aim: CONUS medullaris dermoid cysts are benign lesions, usually observed in the lumbosacral region of the spinal canal. Such lesions are often associated with congenital dermal sinus tracts and spinal dysraphism. Case Presentation: We reported a 37-year-old man with progressive paralysis distal part of the left lower limb presented to our clinic. The MRI of the lumbar spine, as a modality of choice, has revealed a well-defined sausage-shaped lesion, a multilobular cyst, and the heterogeneous contrast enhancement of an intra-and extra-medullary lesion in the CONUS medullaris region. Conclusion: Subtotal microsurgical resection was performed on the lesion. The result of histopathological examination confirmed the dermoid cyst, as well. After conducting the subtotal resection, an appropriate clinical result was achieved in the patient.

Dear EditorFinding a safe location for spinal block during surgical procedures is a matter that requires attention. CONUS medullaris (CM) is the most distal point of the spinal cord and dura that could be visualized on the sagittal sequence. CM location follows a normal distribution, from the lower third of L1 (ranging from the middle third of T12 to the upper third of L3) [1].