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Understanding of the evolutionary history of two closely related canid sister taxa, the geographically restricted, arid-adapted Rüppell’s fox (Vulpes rueppellii) and the widespread generalist red fox (Vulpes vulpes), has been hampered by limited sampling in the biogeographically complex region of North Africa and the Middle East. We sequenced mitochondrial DNA (mtDNA) cytochrome b and D-loop fragments from 116 samples for both species and combined these data with previously published sequences, resulting in 459 haplotypes. Obtained phylogenies showed high support for most branches, including for a newly described ‘Palearctic clade’ that includes North African and Asian individuals from both species. All V. rueppellii individuals fell within the Palearctic clade, forming two previously undescribed subclades that were intermingled with, but not shared with V. vulpes. Our robust placement of V. rueppellii within V. vulpes renders the latter paraphyletic. We propose three scenarios that could explain these observations: (1) rapid, recent speciation of V. rueppellii from V. vulpes, (2) incomplete lineage sorting, or (3) ancient divergence followed by introgression and secondary mtDNA similarity. The third scenario is in best agreement with evidence from the fossil record, and morphometric and ecological distinctiveness between the two taxa, and therefore seems most likely.

Cone snails are venomous predators comprising ~950 species widely distributed in different marine habitats. The production of bioactive molecules (known as conopeptides or conotoxins) marks the Conus as an utmost promising animal source for medicinal applications. This reflects the need for quick and reliable proof of the studied species’ identity. However, identification based on morphological characters has limitations and necessitates complementation with molecular techniques. DNA barcoding based on the mitochondrial cytochrome oxidase subunit I (COI) is currently used as a quick and reliable tool for species identification throughout the globe. The primary objective of this study is to establish reference sequences for Conus species from the Egyptian Red Sea coast, and to evaluate the capacity of DNA barcodes for specimen’ identification. The results of the present study revealed that COI sequences were matched for their maximum identity with those available in the GenBank and BOLD engine and gave matches to Conus species for all studied species (100% match rate). In all cases, DNA analyses were consistent with species classification based on shell characters. According to the phylogenetic tree, all Conus species were recovered as monophyletic and the seven studied species of Conus were well nested in seven separate clades/subclades with closely related species. In conclusion, our study successfully confirms the efficiency of DNA barcoding for specimen identification of different cone snails. Such analytical tool offers great chances for exploring Conus species to better evaluate their status in the Egyptian Red Sea coast, and more generally along the whole Red Sea coast.

Hepatitis C virus (HCV) is a global viral widespread without an available vaccine to prevent infection. HCV infection can cause serious liver diseases such as hepatocellular carcinoma (HCC). Current treatment of HCV infection depends on the FDA approved direct-acting antivirals (DAAs) which have side effects and expensive. Thus, development of a novel, more efficient, along with affordable pricing anti-HCV agents is still required. The purpose of the present study is to evaluate the antiviral effects of bee venom (BV) from the honeybee Apis mellifera on the HCV replication life cycle. The crude venom and its components were examined for their anti-HCV activities using Huh7it-1 cultured cells and the JFH1 strain of HCV genotype 2a. Results revealed that BV inhibited HCV infection with 50% inhibitory concentration (IC50) of 0.05 ng/ml, while the 50% cytotoxic concentration (CC50) being 20,000 ng/ml. The venom directly blocked HCV/cell entry by acting on virus particles in a dose dependent manner, whereas no interference on the host cells. Furthermore, venom showed no inhibitory effect on HCV replication and release. Interestingly, none of the main BV components including the mast cell degranulating peptide (MCD), mpamin, or the small peptides melittin (MLT) showed anti-HCV activity up to 5 μg/ml. In conclusion, these results suggest that BV has a direct virucidal activity against HCV and may exert its antiviral effect through a non-common peptide(s) or toxin complex within the crude venom. Therefore, the crude BV can be considered as a promising candidate for characterization and development of new and natural anti-HCV therapeutic agents.

A sample of 347 specimens of the northern brown shrimp Penaeus aztecus, a western Atlantic species, was collected from July 2019 to June 2020 by local bottom trawlers off two fishing areas, Abu-Qir Bay and Ma’deya, east of Alexandria Coast, Egypt. The species identification was confirmed by morphological and genetic characters. Some aspects of the species’ morphometry and its monthly abundance were briefly discussed. The collected adults were observed from May to November with higher percentage of occurrence in August (29% of total shrimp catch). Sex ratio was 1: 1.2 (F: M). The total length of the adult specimen ranged from 91 mm to 210 mm. COI sequences gave a maximum identity of 99.56% with P. aztecus from Texas and USA, and 99.44% with species from the Eastern Mediterranean. The genetic distance among the studied species from Egypt, USA and the Eastern Mediterranean ranged from 0.2 to 0.7%. The results of this study suggest that P. aztecus may become a new resource for coastal Mediterranean shrimp fisheries.

The highly toxic and medically important scorpion Leiurus quinquestriatus is the most common scorpion species in Egypt and in some regions, is medically problematic for the local population. We stu...

Diabetic wounds are characterized by a delayed closure rate due to the excess inflammation and the inhibition of angiogenesis. Natural products derived from Aloe vera have shown great promise due to their healing magnificent properties. Olive oil is another natural product with anti-microbial and anti-inflammatory properties that may contribute to the healing process. In the present investigation, we tried to evaluate the efficacy of topical application of Aloe gel and/or olive oil in the enhancement of diabetic wounds using histological and immunohistochemical analysis. Excisional wounds were created on the back skin of streptozotocin-induced diabetic rats. Topical treatments of Aloe gel and/or olive oil were applied separately and in a combination (AVO) daily for experimental groups. Macroscopic and microscopic observations of the excision wounds were monitored at time intervals (3, 6, 9, 14 days) post-wounding. Macroscopic observations of the AVO group exhibited almost complete healing at day 14, while other groups were still in progress. Similarly, immunohistochemical analysis of the AVO group showed a mild expression pattern of NF-κB.. While, the cell proliferation (Ki-67), and angiogenesis (CD34) markers were upregulated. Conclusively, the obtained results showed that the AVO combination effectively improved the healing process in diabetic excisional wounds with significant differences in the healing kinetics compared to wounds that received Aloe gel or olive oil separately.

Background Hepatitis C virus (HCV) infection is a major worldwide health problem that can cause liver fibrosis and hepatocellular carcinoma (HCC). The clinical treatment of HCV infection mainly relies on the use of direct-acting antivirals (DAAs) that are usually expensive and have side effects. Therefore, achieving the discovery of more successful agents is always urgent. In this context, antiviral compounds that inhibit viral infections and disease progression with important therapeutic activities have been identified in animal venoms including arthropod toxins. This indicates that arthropod venoms represent a good natural source of promising candidates for new antivirals. Methods The antiviral activity of the wasp venom (WV), isolated from the Oriental hornet (Vespa orientalis), was assessed using cell culture technique with human hepatocellular carcinoma-derived cell line (Huh7it-1) and the recombinant strain of HCV genotype 2a (JFH1). Results The results revealed that WV inhibited HCV infectivity with 50% inhibitory concentration (IC50) of 10 ng/mL, while the 50% cytotoxic concentration (CC50) was 11,000 ng/mL. Time of addition experiment showed that the WV blocked HCV attachment/entry to the cells probably through virucidal effect. On the other hand, the venom showed no inhibitory effect on HCV replication. Conclusion WV can inhibit the entry stage of HCV infection at non-cytotoxic concentrations. Therefore, it could be considered a potential candidate for characterization of natural anti-HCV agents targeting the entry step.

Background: Cell free DNA (cfDNA) analysis in patient plasma has been suggested for screening of different cancers. Healthy cells may shed more degraded DNA than non-apoptotic tumor cells. Objectives: Our goal was to check whether DNA fragments extracted from patient’s plasma with bladder cancer (BC) had higher integrity than DNA purified from plasma of healthy controls. Methods: cfDNA was extracted from the plasma of a healthy control group and patients with BC. The association between clinical status and length of DNA fragments was examined. Plasma cfDNA integrity was examined using multiplex PCR with specific primers producing progressively long PCR fragments (200, 400 & 800-bp). Length and concentration of PCR amplicons obtained from BC patients and healthy individuals were compared. Results: Using a multiplex PCR assay, the used p53 primers efficiently amplified the increasingly long fragments. High molecular weight DNA fragments (400 & 800-bp) in the plasma cfDNA are associated with the presence of cancer. Moreover, elevation of the 200-bp fragment concentration in the plasma cfDNA is significantly (p < 0.002) associated with the presence of cancer. Conclusions: The detected long DNA fragments in plasma cfDNA is associated with BC indicating that the multiplex PCR assay of plasma cfDNA integrity could be a useful future marker for the detection of BC.

Labrids (wrasses) are characterized by great phenotypic differentiation during development. Most wrasses are brightly colored, often with complex patterns. They usually display extreme color variation between sexes to the point of considering them different species. The purpose of this paper is to re-examine intra-specific sexual dimorphism in two common wrasses; Cheilinus lunulatus and Halichoeres hortulanus. We used morphometric and DNA barcoding analyses to determine whether morphological differences are due to gender or species differences. Results showed that most of body related measurements in males and females were sexually dimorphic. However, no distinct difference was observed in cytochrome oxidase subunit I (COI) sequence between the examined individuals of C. lunilatus and those of H. hortulanus, thus confirming that the phenotypic differences are due to sexual dimorphism and not species differences. Keywords: Sexual dimorphism, DNA barcoding, Labrid fish, Cheilinus lunulatus, Halichoeres hortulanus

Growing global viral infections have been a serious public health problem in recent years. This current situation emphasizes the importance of developing more therapeutic antiviral compounds. Hepatitis C virus (HCV) and dengue virus (DENV) belong to the Flaviviridae family and are an increasing global health threat. Our previous study reported that the crude venom of Scorpio maurus palmatus possessed anti-HCV and anti-DENV activities in vitro. We report here the characterization of a natural antiviral peptide (scorpion-like peptide Smp76) that prevents HCV and DENV infection. Smp76 was purified from S. m. palmatus venom and contains 76 amino acids with six residues of cysteine. Smp76 antiviral activity was evaluated using a cell culture technique utilizing Huh7it-1, Vero/SLAM, HCV (JFH1, genotype 2a) and DENV (Trinidad 1751, type 2). A potential antiviral activity of Smp76 was detected in culture cells with an approximate IC50 of 0.01 μg/ml. Moreover, Smp76 prevents HCV infection and suppresses secondary infection, by inactivating extra-cellular infectious particles without affecting viral replication. Interestingly, Smp76 is neither toxic nor hemolytic in vitro at a concentration 1000-fold higher than that required for antiviral activity. Conclusively, this report highlights novel anti-HCV and anti-DENV activities of Smp76, which may lay the foundation for developing a new therapeutic intervention against these flaviviruses.

The taxonomic identity of canids of the genus Canis in North Africa has been investigated using molecular phylogenetic analysis based on Cytochrome b mitochondrial DNA sequence analysis. Tissue samples from 18 Canis specimens collected from all known populations/taxa in Egypt were obtained and analyzed. The resulting Cyt b mt DNA sequences of current Canis taxa, described based morphological characters were compared to each other and to other Canis populations/taxa across North Africa and the Middle East. The results showed no detectable sequence differentiation among all populations, suggesting that the separation of the phenotypically differentiated populations of Egypt has been relatively recent. Estimate divergence time between different phylogroups of the genus and the phylogeographic history of the genus was discussed in a regional paleogeographic context.

Background: 2% to 3% of all living newborns showed at least one recognizable congenital malformation. Monosodium glutamate (MSG) is widely used as flavor enhancer. But, it induces embryonic and fetal toxicity in rats during the gestational periods. Aim of the work: this study aimed to detect the effects of MSG on placenta and fetal developmental stages at 15th and 19th days of gestation. Material and Methods: fifty mature pregnant Albino rats (Weight 200 ± 20 g) were categorized into two groups according to the time of dissection at 15thor 19th days of gestation. From each group, half of the pregnant mothers (G15 and G19)were daily administrated MSG ( 7 g/10mL/kg b. w. by oral)from the 9th to 14th days of gestation). The control groups (C15 and C 19) were received water only. Results: in G15 and G19 groups, the uterine and fetal shape, number of implantation sites, number of living fetuses, body length, fetal and placental weights and the placental co-efficient were negatively changed when compared to the control groups(C15 and C 19). Also, the placental tissue showed congested blood sinuses and large hemorrhagic areas which contained hemolysed blood cells. Some atrophied decidual cells and pyknotic nuclei were observed with highly distorted maternal and fetal placental layers. Conclusions: this study showed that shortterm MSG exposure caused several maternal and fetal changes. Therefore, MSG is considered as embryotoxic agent and the mothers must avoid administration of this substance during the gestation period

Background: monosodium glutamate (MSG) is a widely used flavor enhancer and stabilizer in readymade or packaged foods. The excessive use of MSG increases the oxidative stress in the different body systems and causes teratogenic effects on fetuses of mothers treated with it in the gestational periods. Aim of the work: this study investigated effects of MSG on maternal and fetal liver tissue. Material and Methods: the present work was carried out on fifty mature pregnant Albino rats (Weight 200 ± 20 g) and six male rats in the reproductive age (Older than 60 days). The first group was served as the control group. The remnant pregnant rats were categorized into two sub- groups. Animals of the 1st sub group were dissected on day 15th of gestation (C15) and the second was dissected on day 19th (C19) of gestation. The second group was administrated monosodium glutamate daily with the dose of 7 g/10mL/kg body weight from the 9th to 14th of gestation. Then the pregnant mothers were categorized into two sub- groups, the first was dissected on the 15th day (G15) and the second on the 19th day (G19) of gestation. The pregnant mothers were dissected after anesthesia which was performed by Halothane produced by Pharco. Comp. The uterine horns were removed from the surrounding fats then fetuses were removed from the surrounding amniotic membranes. Histopathological and histochemical studies were done on the maternal and fetal liver tissue through hematoxylin-eosin stain and Feulgen reaction. Results: numerous degenerative changes were detected in both maternal and fetal liver tissues of G15 and G19 groups. These changes included: vacuolation in hepatocytes, degenerative and necrotic areas and atrophied size of hepatocytes with pyknotic nuclei. These changes were observed in the centrolobular zones and the portal zones. Conclusions: This study showed that short-term MSG exposure in the gestational periods caused several histological and histochemical changes in the maternal and fetal liver tissues. These findings should be re-evaluated in additional long-term studies.

The Egyptian Wolf Canis lupaster was recently rediscovered as a distinct species on the basis of both morphologic and molecular genetic evidence. Phenotypical variability, including coat colour of ...

The geographical distribution and diversity of the scorpion fauna of Egypt was examined based on a large collection covering most of the country and in view of recent revisionary systematics. Six ecologically distinct zoogeographical regions are targeted in a collection scheme. The ecological and historical biogeography of the present-day distribution of the scorpion fauna of Egypt is discussed.

Background: The medically important desert-horned or Egyptian sand viper (Cerastes cerastes) is one of the most familiar snakes of the great deserts of North Africa and the Middle East. It is a poisonous and widely distributed snake in Africa and inhabits the sandy deserts of Egypt. Male and female specimens of C. cerastes have been compared from different aspects. Results: Morphologically, tail length relative to snout-vent length was compared. Males significantly showed longer tails than do females. From the venom aspect, males showed a significant (p

Acanthodactylus is a genus of lacertid lizard, commonly referred to as fringe-fingered lizards or fringe-toed lizards. The systematics of the genus Acanthodactylus was classically based on external morphological traits, osteological characters and morphology of the hemipenes. In this study, partial sequences of 18S rRNA gene were used to estimate the relationships among three lacertide species from Egypt: Acanthodactylus boskianus, Acanthodactylus scutellatus and Acanthodactylus longipes. These data were used together with morphological information, to evaluate the relationships among these three species. DNA was extracted from the collected specimens, 988 bp fragment of 18S rRNA was amplified using universal primers and sequenced. The obtained sequences were analyzed and a phylogenetic tree was constructed. Results of analysis revealed that A. scutellatus and A. longipes form a very well supported clade with 86% bootstrap. A. boskianus was found to constitute a separate clade. The resultant tree based on DNA sequence data was similar to that produced from a differentially weighted data set of morphological characters. In conclusion, the 18S rRNA gene sequence seems to be a good marker for phylogenetic analysis of Acanthodactylus species.

Hepatitis C virus (HCV) infection is a major worldwide health problem which can cause chronic hepatitis, liver fibrosis and hepatocellular carcinoma (HCC). There is still no vaccine to prevent HCV infection. Currently, the clinical treatment of HCV infection mainly relies on the use of direct-acting antivirals (DAAs) which are expensive and have side effects. Here, BmKDfsin3, a scorpion defensin from the venom of Mesobuthus martensii Karsch, is found to dose-dependently inhibit HCV infection at noncytotoxic concentrations and affect viral attachment and post-entry in HCV life cycle. Further experimental results show that BmKDfsin3 not only suppresses p38 mitogen-activated protein kinase (MAPK) activation of HCV-infected Huh7.5.1 cells, but also inhibits p38 activation of Huh7.5.1 cells stimulated by tumor necrosis factor-&alpha, (TNF-&alpha, ), interleukin-1&beta, (IL-1&beta, ) or lipopolysaccharide (LPS). BmKDfsin3 is also revealed to enter into cells. Using an upstream MyD88 dimerization inhibitor ST2345 or kinase IRAK-1/4 inhibitor I, the inhibition of p38 activation represses HCV replication in vitro. Taken together, a scorpion defensin BmKDfsin3 inhibits HCV replication, related to regulated p38 MAPK activation.

B lymphocyte induced maturation protein (Blimp-1) is present in a variety of organisms from nematode to human as a factor carrying well conserved five DNA binding zinc fingers and relatively conserved PR/SET domain. Blimp-1 was found to play important roles in various aspects of development in many organisms andworks mainly as a repressor to suppress many different genes. Blimp-1 inDrosophila was identified as a transcriptional repressor binds to the promoter region of the ftz-f1 gene. To understand the mechanism of how Drosophila Blimp-1 controls expression of its target genes, Blimp-1 was purified from prepared nuclear extract with its interacting proteins. The purified proteins were identified using Liquid chromatography-mass spectrometry (LC-MS/MS) after trypsin digestion. Results of this analysis revealed presence of several peptides of Histone H4 as interacting protein. It could be suggested that Blimp-1 function through a histone-masking mechanism and has an important regulatory chromatin remodeling.

Various bioactive peptides have been identified in scorpion venom, but there are many scorpion species whose venom has not been investigated. In this study, we characterized venom components of the North African scorpion, Buthacus leptochelys, by mass spectrometric analysis and evaluated their insect toxicity. This is the first report of chemical and biological characterization of the B. leptochelys venom. LC/MS analysis detected at least 148 components in the venom. We isolated four peptides that show insect toxicity (Bl-1, Bl-2, Bl-3, and Bl-4) through bioassay-guided HPLC fractionation. These toxins were found to be similar to scorpion &alpha, and &beta, toxins based on their N-terminal sequences. Among them, the complete primary structure of Bl-1 was determined by combination of Edman degradation and MS/MS analysis. Bl-1 is composed of 67 amino acid residues and crosslinked with four disulfide bonds. Since Bl-1 shares high sequence similarity with &alpha, like toxins, it is likely that it acts on Na+ channels of both insects and mammals.

A novel anti-mollusk conopeptide pn4c was isolated from the Conus pennaceus venom by repeated HPLC fractionation based on the activity against freshwater snails. The primary structure of pn4c was determined by the mass spectrometric de novo sequencing analysis. In addition, pn3a was isolated from the same fraction containing pn4c, as a peptide with unknown functions.

The taxonomy and diversity of the scorpion fauna of Egypt was examined based on a large collection from most parts of the country and in view of recent revisionary systematics. We assessed the validity of listed records in light of new taxonomic findings and geographic distribution data and present a new list and an identification key to the scorpion fauna of Egypt consisting of 31 species, 18 of which were collected during this survey. Four species were not accepted for the list because no voucher material was available.

Scorpions use their venom to immobilize prey items and defend themselves against predators. Scorpion venom is a complex mixture composed of a wide array of substances such as salts, small molecules, peptides, and proteins. During analysis of the prey capture behavior of the scorpion Parabuthus leiosoma, we noticed that the scorpion stings the prey several successive stings in different specific regions. The stings started with ventral surface of the abdomen followed by thorax, shoulders and finally the head. This finding raised the possibility that the scorpion might use the venom with different composition in different contexts. To check this possibility, venom was collected as sequential drops (stings) by electrical stimulation (20 Volt) of the telson of the Parabuthus leiosoma. Protein content was determined by spectrophotometer using total protein KIT. The results showed marked variation of the total protein among the consecutive stings of each of the investigated scorpions. To go further, the protein profiles for all the collected stings were analyzed separately using 10% SDS-polyacrylamide electrophoresis (SDS-PAGE). Similarly, differences were observed among the stings, not only in the number of the protein bands, but also in the intensity of the bands. Thus, these results indicated that different venom components are unequally represented among consecutive stings supporting the venom-metering hypothesis.

Regulatory mechanisms controlling the timing of developmental events are crucial for proper development to occur. ftz-fl is expressed in a temporally regulated manner following pulses of ecdysteroid and this precise expression is necessary for the development of Drosophila melanogaster. To understand how insect hormone ecdysteroids regulate the timing of FTZ-F1 expression, we purified a DNA binding regulator of ftz-fl. Mass spectroscopy analysis revealed this protein to be a fly homolog of mammalian B lymphocyte-induced maturation protein 1 (Blimp-1). Drosophila Blimp-1 (dBlimp-1) is induced directly by 20-hydroxyecdysone, and its product exists during high-ecdysteroid periods and turns over rapidly. Forced expression of dBlimp-1 and RNA interference analysis indicate that dBlimp-1 acts as a repressor and controls the timing of FTZ-F1 expression. Furthermore, its prolonged expression results in delay of pupation timing. These results suggest that the transient transcriptional repressor dBlimp-1 is important for determining developmental timing in the ecdysone-induced pathway.

Over 200 components with molecular mass ranging mainly from 400 to 4000 Da were characterized from the venom of the vermivorous cone snail Conus fulgetrum that inhabit Egyptian Red Sea. One major component having a molecular mass of 2946 Da was purified by HPLC, and its primary structure was determined by a combination of Edman degradation and MS/MS analysis.

During the development of multicellular organisms, many events occur with precise timing. In Drosophila melanogaster, pupation occurs about 12 hours after puparium formation, and its timing is believed to be determined by the release of a steroid hormone, ecdysone (E), from the prothoracic gland. Here, we demonstrate that the ecdysone-20-monooxygenase, Shade, determines the pupation timing by converting E to 20-hydroxyecdysone (20E) in the fat body, which is the organ that senses nutritional status. The timing of shade expression is determined by its transcriptional activator βFTZ-F1. The βFTZ-F1 gene is activated after a decline in the expression of its transcriptional repressor Blimp-1, which is temporally expressed around puparium formation in response to a high titer of 20E. The expression level and stability of Blimp-1 is critical for the precise timing of pupation. Thus, we propose that Blimp-1 molecules function as sands in an hourglass for this precise developmental timer system. Furthermore, our data suggest a biological advantage results from both the use of a transcriptional repressor for the time determination, and association of developmental timing with nutritional status of the organism.

Background Hepatitis C virus (HCV) is a major global health problem, causing chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. Development of well-tolerated regimens with high cure rates and fewer side effects is still much needed. Recently, natural antimicrobial peptides (AMPs) are attracting more attention as biological compounds and can be a good template to develop therapeutic agents, including antiviral agents against a variety of viruses. Various AMPs have been characterized from the venom of different venomous animals including scorpions. Methods The possible antiviral activities of crude venoms obtained from five Egyptian scorpion species (Leiurus quinquestriatus, Androctonus amoreuxi, A. australis, A. bicolor and Scorpio maurus palmatus) were evaluated by a cell culture method using Huh7.5 cells and the J6/JFH1-P47 strain of HCV. Time-of-addition experiments and inactivation of enzymatic activities of the venoms were carried out to determine the characteristics of the anti-HCV activities. Results S. maurus palmatus and A. australis venoms showed anti-HCV activities, with 50% inhibitory concentrations (IC50) being 6.3 ± 1.6 and 88.3 ± 5.8 μg/ml, respectively. S. maurus palmatus venom (30 μg/ml) impaired HCV infectivity in culture medium, but not inside the cells, through virocidal effect. The anti-HCV activity of this venom was not inhibited by a metalloprotease inhibitor or heating at 60°C. The antiviral activity was directed preferentially against HCV. Conclusions S. maurus palmatus venom is considered as a good natural source for characterization and development of novel anti-HCV agents targeting the entry step. To our knowledge, this is the first report describing antiviral activities of Egyptian scorpion venoms against HCV, and may open a new approach towards discovering antiviral compounds derived from scorpion venoms.