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Reproductive toxic effects of Tityus serrulatus scorpion venom in rats

CRUTTENDEN, Karen; NENCIONI, Ana Leonor A.; BERNARDI, Maria Martha; DORCE, Valquiria A. C.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD Publicador: PERGAMON-ELSEVIER SCIENCE LTD
Tipo: Artigo de Revista Científica
Português
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Tityus serrulatus is the most venomous scorpion in Brazil. Little is known about the effect of maternal exposure to the venom on fetal development. We investigated the effect of low to moderate doses of the venom (0.3 or 1.0 mg/kg s.c. on either day 5 or day 10 of gestation) on pregnant rats and on their offspring. For dams, we observed their body weight gain and reproductive parameters. For the offspring, we observed their body weight and weight of internal organs and the number of live and dead fetuses, and we investigated whether the venom caused external, visceral, skeletal or histopathological alterations in the offspring. The offspring were examined on gestational day 21. Injection of the venom on gestational day 5 did not change the reproductive parameters of the dams, their weight or fetuses` weight. Rats that received the high dose of the venom (1.0 mg/kg) on gestational day 10 had heavier placentas and heavier fetuses with heavier lungs. Injections on day 10 of gestation did not alter the reproductive parameters of the dams nor their weight gain at either dose. The venom did not cause malformations of the fetal skeleton or viscera and did not delay fetal development with either dose. In conclusion, subcutaneous administration of 0.3 or 1.0 mg/kg T. serrulatus venom to pregnant Wistar rats at either day 5 or day 10 of gestation did not cause maternal or clear fetal toxicity. Subtle increases in placental weight and fetal body and lung weights observed following treatment with 1.0 mg/kg on day 10 of gestation were not associated with histopathological findings. Whether these observations represent a reaction to treatment and...

Busca de novos substratos e/ou inibidores das enzimas timet oligopeptidase (E.C.3.4.24.15) e neurolisina (E.C.3.4.24.16) nas frações de baixa massa molecular do veneno do escorpião Tityus serrulatus.; Search for new substrates and/or inhibitors of thimet oligopeptidase (EC3.4.24.15) and neurolysin (EC3.4.24.16) enzymes in low molecular weight fractions of Tityus serrulatus scorpion venom.

Duzzi, Bruno
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/05/2014 Português
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59.126436%
O escorpião Tityus serrulatus é o responsável pelos acidentes mais graves no Brasil. Dentre os componentes já estudados de sua peçonha estão neurotoxinas capazes de interagir com canais iônicos, além de peptídeos biologicamente ativos também estarem presentes. Neste estudo foram isolados peptídeos da fração de baixa massa molecular da peçonha que interagiram com as oligopeptidases timet oligopeptidase (EP24.15) e neurolisina (EP24.16) através do emprego de substratos fluorescentes específicos como ferramentas. Usando espectrometria de massas, as sequências KEILG, FTR, YLPT e do análogo KELLG foram determinadas e posteriormente sintetizadas. In vitro, os peptídeos não foram substratos para enzimas já citadas, além de testes com a neprelisina e ECA. Em relação à inibição, os destaques ficam por conta de KELLG e KEILG, capazes de inibirem a EP 24.15 e de não inibirem a EP 24.16. Outro destaque foi o YLPT, apresentando um Ki de 0,94 mM perante a neprilisina. In vivo os peptídeos foram testados em relação à nocicepção, rolamento de leucócitos e reatividade vascular, onde se destacou o FTR, apresentando efeito antinociceptivo e o KEILG, capaz de aumentar o número de leucócitos, ressaltando a importância de pequenas moléculas na composição da peçonha.; The scorpion Tityus serrulatus is responsible for the most serious accidents in Brazil. Among the components already studied in its venom...

Isolation, homology modeling and renal effects of a C-type natriuretic peptide from the venom of the Brazilian yellow scorpion (Tityus serrulatus)

Alves, Renata S.; Ximenes, Rafael M.; Jorge, Antonio R.C.; Nascimento, Nilberto R.F.; Martins, René D.; Rabello, Marcelo M.; Hernandes, Marcelo Z.; Toyama, Daniela O.; Toyama, Marcos H.; Martins, Alice M.C.; Havt, Alexandre; Monteiro, Helena S.A.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 19-26
Português
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59.233594%
Mammalian natriuretic peptides (NPs) have been extensively investigated for use as therapeutic agents in the treatment of cardiovascular diseases. Here, we describe the isolation, sequencing and tridimensional homology modeling of the first C-type natriuretic peptide isolated from scorpion venom. In addition, its effects on the renal function of rats and on the mRNA expression of natriuretic peptide receptors in the kidneys are delineated. Fractionation of Tityusserrulatus venom using chromatographic techniques yielded a peptide with a molecular mass of 2190.64Da, which exhibited the pattern of disulfide bridges that is characteristic of a C-type NP (TsNP, T. serrulatus Natriuretic Peptide). In the isolated perfused rat kidney assay, treatment with two concentrations of TsNP (0.03 and 0.1μg/mL) increased the perfusion pressure, glomerular filtration rate and urinary flow. After 60min of treatment at both concentrations, the percentages of sodium, potassium and chloride transport were decreased, and the urinary cGMP concentration was elevated. Natriuretic peptide receptor-A (NPR-A) mRNA expression was down regulated in the kidneys treated with both concentrations of TsNP, whereas NPR-B, NPR-C and CG-C mRNAs were up regulated at the 0.1μg/mL concentration. In conclusion...

Effect of toxin-g from Tityus serrulatus scorpion venom on gastric emptying in rats

Bucaretchi,F.; Vinagre,A.M.; Chavéz-Olórtegui,C.; Collares,E.F.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/1999 Português
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69.031973%
The effect of toxin-g from Tityus serrulatus scorpion venom on the gastric emptying of liquids was studied in 176 young adult male Wistar rats (2-3 months of age) divided into subgroups of 8 animals each. Toxin-g was injected iv at doses of 25, 37.5, 50 or 100 µg/kg and the effect on gastric emptying was assessed 30 min and 8 h later. A time-course study was also performed by injecting 50 µg of toxin-g /kg and measuring the effect on gastric emptying at times 0.25, 0.5, 1, 2, 4, 8, 24 and 48 h post-venom. Each envenomed animal was paired with its saline control and all received a saline test meal solution containing phenol red (60 µg/ml) as a marker. Ten minutes after administering the test meal by gavage the animals were sacrificed and gastric retention was determined by measuring the residual marker concentration of the test meal. A significant delay in gastric emptying, at 30 min and 8 h post-venom, was observed only after 50 and 100 µg of toxin-g /kg compared to control values. The responses to these two doses were significantly different after 8 h post-venom. Toxin-g (50 µg/kg) significantly delayed the gastric emptying of liquids at all times studied...

Age effects on the pharmacokinetics of tityustoxin from Tityus serrulatus scorpion venom in rats

Nunan,E.A.; Arya,V.; Hochhaus,G.; Cardoso,V.N.; Moraes-Santos,T.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2004 Português
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69.145356%
The pharmacokinetics of scorpion venom and its toxins has been investigated in experimental models using adult animals, although, severe scorpion accidents are associated more frequently with children. We compared the effect of age on the pharmacokinetics of tityustoxin, one of the most active principles of Tityus serrulatus venom, in young male/female rats (21-22 days old, N = 5-8) and in adult male rats (150-160 days old, N = 5-8). Tityustoxin (6 µg) labeled with 99mTechnetium was administered subcutaneously to young and adult rats. The plasma concentration vs time data were subjected to non-compartmental pharmacokinetic analysis to obtain estimates of various pharmacokinetic parameters such as total body clearance (CL/F), distribution volume (Vd/F), area under the curve (AUC), and mean residence time. The data were analyzed with and without considering body weight. The data without correction for body weight showed a higher Cmax (62.30 ± 7.07 vs 12.71 ± 2.11 ng/ml, P < 0.05) and AUC (296.49 ± 21.09 vs 55.96 ± 5.41 ng h-1 ml-1, P < 0.05) and lower Tmax (0.64 ± 0.19 vs 2.44 ± 0.49 h, P < 0.05) in young rats. Furthermore, Vd/F (0.15 vs 0.42 l/kg) and CL/F (0.02 ± 0.001 vs 0.11 ± 0.01 l h-1 kg-1, P < 0.05) were lower in young rats. However...

Tc 99m - SCORPION VENOM: LABELLING, BIODISTRIBUTION AND SCINTIIMAGING

MURUGESAN,S.; RADHA KRISHNA MURTHY,K.; NORONHA,O. P. D.; SAMUEL,A. M.
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/1999 Português
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69.53664%
Labelling of scorpion (Mesobuthus tamulus concanesis Pocock) venom was successfully achieved with Tc 99m using direct tin reduction procedure. Biodistribution studies were carried out in Wistar rats at different time intervals after i.v. administration of the labelled venom. Scintiimages were obtained after scorpion envenoming using a large field of view gamma camera to ascertain the pharmacological action of venom in the body. Within 5 min of administration, labelled venom was found in the blood (27.7%), muscle (30.11%), bone (13.3%), kidneys (11.5%), liver (10.4%), and other organs. The level of venom in the kidneys was higher than in the liver. The labelled venom was excreted through renal and hepatobiliary pathways. An immunoreactivity study was carried out in rabbits after i.v. injection of labelled scorpion venom followed by the injection of the species specific antivenom. A threefold increase in uptake by the kidneys was observed compared with that seen with scorpion venom alone. The neutralisation of the venom in the kidneys was higher than in the liver.

The use of antivenom reverses hematological and osmotic fragility changes of erythrocytes caused by indian red scorpion Mesobuthus tamulus concanesis POCOCK in experimental envenoming

RADHA KRISHNA MURTHY,K.; ABBAS ZARE,M.
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2001 Português
Relevância na Pesquisa
59.4153%
Acute myocarditis was induced in experimental dogs by subcutaneous (SC) injection of 3mg/kg of scorpion venom from Mesobuthus tamulus concanesis POCOCK (earlier called Buthus tamulus). An increase in hemoglobin (Hb), mean corpuscular hemoglobin concentration (MCHC), packed cell volume (PCV), plasma hemoglobin (Plasma Hb) levels, and increased osmotic fragility of erythrocytes in vivo was observed after envenoming. An increase in osmotic fragility of red blood cells (RBC) was also observed when the blood in vitro was incubated with different concentrations of scorpion venom. Species- specific scorpion antivenom (SAV) was administered to different groups of animals at different time intervals following scorpion envenoming. This resulted in a decrease in Hb, MCHC, PCV, and plasma Hb levels in the envenomed animals and reversal of osmotic fragility changes of erythrocytes. It has been suggested that scorpion venom causes an autonomic storm releasing massive amounts of counter-regulatory hormones, such as catecholamines, angiotensin-II, glucagon, cortisol, and changes in insulin secretion resulting in hematological and osmotic fragility changes of erythrocytes. Administration of SAV effectively neutralized, prevented, and reversed scorpion venom toxicity and related osmotic fragility changes of erythrocytes.

SCORPION ANTIVENOM REVERSES METABOLIC, ELECTROCARDIOGRAPHIC, AND HORMONAL DISTURBANCES CAUSED BY THE INDIAN RED SCORPION Mesobuthus tamulus concanesis, Pocock ENVENOMATION

MURTHY,K. RADHA KRISHNA; ZARE,M. ABBAS
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2002 Português
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59.3695%
Electrocardiographic (ECG) changes were induced in dogs by injection of scorpion venom from Mesobuthus tamulus concanesis, Pocock. Venom (3 mg/kg body weight) was given subcutaneously (SQ) while 10 ml of scorpion antivenom (SAV) was administered intravenously (IV) to experimental dogs. Group 1 received only the venom; Groups 2, 3, and 4 received SAV at 0, 30, and 60 min, respectively, following envenoming. Thick, ropy and profuse salivation; muscle fasciculation; clonus and tetany-like contractions; frequent urination; and bowel emptying sometimes stained with bile and occasionally blood and bile were observed 20-25 minutes after envenoming. Following envenoming, hyperglycemia, increase in free fatty acid (FFA) levels, and reduction in triglyceride levels were observed in Groups 1, 3, and 4. There was an initial rise in insulin levels at 30 min followed by a reduction at 60 min. SAV caused a subsequent rise in insulin levels but there was a reduction in blood sugar to euglycemia levels and lipogenesis (reduction in FFA and increase in triglycerides levels) in Groups 3 and 4. Abnormal ECG changes and arrhythmias were not observed after SAV. Normal sinus rhythm was restored in Group 4. Scorpion envenoming with multi-system-organ failure (MSOF)...

Cytotoxic and apoptotic effects of scorpion Leiurus quinquestriatus venom on 293T and C2C12 eukaryotic cell lines

Omran,M. A. A.
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2003 Português
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59.29732%
Scorpion venom toxicity is of major concern due to its influence on human activities and public health. The cytotoxicity and apoptosis induced by scorpion L. quinquestriatus venom on two established eukaryotic cell lines (293T and C2C12) were analyzed. Both cultured cell lines were incubated with varying doses (10, 20, and 50 µg/ml) of scorpion venom in serum free medium (SFM) for 0.5, 1, 2, 4, and 8 hours at 37°C. The percentage of total lactate dehydrogenase (LDH) released in the culture during venom incubation was used as an index of cell damage. Control culture was treated with an equal amount of SFM. Cell injury was recognized morphologically and apoptosis was researched by a Fluorescing Apoptosis Detection System using the principle of TUNEL (TdT-mediated dUTP Nick-End Labelling) assay and confirmed by another assay concerning nuclear DNA staining with DAPI stain. Cytotoxicity was remarkable and cell survival highly reduced at the highest tested concentration (50 µg/ml). These effects were rapid and observed within 30 minutes. The apparent initial damage to the nucleus and lysis of the plasmalemma and/or organelle membranes, which was evident by a significant increase in cytosolic LDH release, suggested that this toxin acts at the membrane level. The morphological changes that occurred in apoptotic cells include condensation and compartmentalization of nuclear and cytoplasmic materials into structurally preserved membrane-bound fragments or blebs. The cytotoxic effects are dose and time dependent and cell death by apoptosis was more characteristic of 293T cells than C2C12 cells. The apoptotic effects were more prominent and clear in the early stages of toxicity...

The effects of a sodium and a calcium channel blocker on lethality of mice injected with the yellow scorpion (Leiurus quinquestriatus) venom

Al-Shanawani,A. R.; Fatani,A. J.; El-Sayed,F. H.
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2005 Português
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59.35209%
Scorpion venom toxins generally produce similar effects by mainly acting on sodium channels, and to a lesser extent, on potassium, calcium, and chloride channels. This leads to increased release of neurotransmitters and mediators, resulting in a cascade of pathological events, involving the central nervous system, the autonomic nervous system, the cardiovascular and the respiratory system, eventually leading to death. The objective of this paper was to discover whether a sodium channel blocker, lidocaine, or a calcium channel blocker, verapamil, would prolong the survival of mice injected with the venom from the common yellow scorpion Leiurus quinquestriatus quinquestriatus (LQQ). For this purpose, mice were divided into 2 groups, each injected with a different venom dose (250 or 300 µg.kg-1, s.c.). Subgroups (n=10) from each group were given venom alone; different doses of lidocaine (4, 10, 15, or 20 mg.kg-1); or several doses of verapamil (0.01, 0.03, 0.1, 0.3, or 1 mg.kg-1). All doses of lidocaine and verapamil were intravenously administered 3 minutes before, 1, 5, and 15 minutes after venom injection. Percent surviving after 24 hours was recorded in addition to the time of death. In general, lidocaine significantly prolonged survival at the dose of 10 mg.kg-1 (P<0.05 and P<0.01...

Biochemical changes and manifestations of envenomation produced by Odonthobuthus doriae venom in rabbits

Mirakabadi,A. Z.; Jalali,A.; Jahromi,A. E.; Vatanpur,H.; Akbary,A.
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2006 Português
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59.126436%
Many toxins from scorpion venoms cause neurotransmitters release by activating the autonomic system. The aim of the present work was to determine osmotic fragility of red blood cells (RBCs) and serum biochemical changes produced by the venom of Odonthobuthus doriae (O. doriae), a dangerous species of scorpion in Iran. For this study we selected 2 groups, each one containing 10 New Zealand white rabbits weighing 2 ± 0.2 kg. In vivo and in vitro osmotic fragilities as well as packed cell volume (PCV) were determined. Serum was separated and used for determination of glucose, blood urea nitrogen (BUN), creatinine, uric acid (UA), triglycerides, cholesterol, aspartate aminotransferase (AST, EC 2.6.1.1), and alanine aminotransferase (ALT, EC 2.6.1.2). Results indicate that Odonthobuthus doriae venom (0.5 mg/kg, IV) causes a significant increase (p<0.05) of serum glucose, UA, PCV, ALT, and AST. Increase was also observed in BUN, but it was not statistically significant. On the other hand a significant decrease (p<0.05) was observed in triglycerides and cholesterol levels. Increased in vivo osmotic fragility of RBCs was significant too, but in vitro osmotic fragility did not show a significant change. These results support the hypothesis that the biochemical variation caused by scorpion venom can be due to an autonomic storm and release of catecholamines.

Effect of selected anti-inflammatory drugs on the lethal actions of Leiurus quinquestriatus venom

Abdoon,N. A.; Ali,A. A.; Alnema,A. A.; Hag-Ali,M.; Fatani,A. J.
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2006 Português
Relevância na Pesquisa
59.383213%
The cumulative actions of scorpion neurotoxins are complex and may be traced to activation of different ion channels with subsequent release of various transmitters and modulators including inflammatory mediators. This could lead to various pathological manifestations such as acute respiratory distress syndrome (ARDS), systemic inflammatory response syndrome (SIRS), and multiple organ failure (MOF). Several approaches have been advocated to treat the multitude of scorpion-venom-elicited pathological changes. However, few have tried to combat the venom-induced effects on the inflammatory process, which manifest as ARDS, SIDS and MOF. Thus, the aim of this study was to determine the capability of inhibitors of different steps of the inflammatory sequence of events in scorpion envenomation to ameliorate the detrimental action of the venom and prolong survival of mice injected with Leiurus quinquestriatus quinquestriatus (LQQ) venom. Animals were divided into groups (n = 10) and given montelukast (10 or 20 mg.kg-1, orally), hydrocortisone (5 or 10 mg.kg-1, intravenously) or indomethacin (10 or 20 mg kg-1, intravenously). Then, all animals were subcutaneously injected with either 0.25 or 0.3 mg.kg-1 LQQ venom. Signs and symptoms of envenomation were recorded and survival percentages after 24 hours as well as survival time were determined in each group. To analyze data...

Embriotoxic effects of maternal exposure to Tityus serrulatus scorpion venom

Barão,A. A. S.; Nencioni,A. L. A.; Dorce,V. A. C.
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2008 Português
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59.148184%
Tityus serrulatus is the most venomous scorpion in Brazil; however, it is not known whether its venom causes any harm to the offspring whose mothers have received it. This study investigates whether the venom of T. serrulatus may lead to deleterious effects in the offspring, when once administered to pregnant rats at a dose that causes moderate envenomation (3mg/kg). The venom effects were studied on the 5th and on the 10th gestation day (GD5 and GD10). The maternal reproductive parameters of the group that received the venom on GD5 showed no alteration. The group that received the venom on GD10 presented an increase in post-implantation losses. In this group, an increase in the liver weight was also observed and one-third of the fetuses presented incomplete ossification of skull bones. None of the groups that received the venom had any visceral malformation or delay in the fetal development of their offspring. The histopathological analysis revealed not only placentas and lungs but also hearts, livers and kidneys in perfect state. Even having caused little effect on the dams, the venom may act in a more incisive way on the offspring, whether by stress generation or by a direct action.

Histology and histochemistry of the venom apparatus of the black scorpion Androctonus crassicauda (Olivier, 1807) (Scorpiones: Buthidae)

Jarrar,BM; Al-Rowaily,MA
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2008 Português
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59.238345%
The venom apparatus of the black scorpion Androctonus crassicauda has been characterized histologically and histochemically in the present study. The results showed that this apparatus consists of paired venom glands, each of which initially presents its own canal and posteriorily both fuse into a single common one. Each gland is covered by a sheath of striated muscle and is lined with extensively folded secretory epithelium (formed of non-secretory and secretory venom-producing cells). The outcomes also revealed that the venom-producing cells of both glands produce neutral mucosubstances, sialomucins, sulfomucins and proteins, but are devoid of glycogen. Cysteine, tyrosine, tryptophan and arginine were also detected along with activities of acid and alkaline phosphatases, mitochondrial adenosine triphosphatase, aminopeptidase, cholinesterase and non-specific esterases. Structure and secretion of scorpion venom glands are discussed within the context of the present results.

A newly described scorpion species, Leiurus abdullahbayrami (Scorpion: Buthidae), and the lethal potency and in vivo effects of its venom

Ozkan,O; Yagmur,EA; Ark,M
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 Português
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59.620137%
Currently, medically significant scorpion species belong to the Buthidae family and are represented by the genera Androctonus, Buthus, Mesobuthus, Hottentotta, Parabuthus, Tityus, Centruroides, Leiurus. Although Leiurus was originally considered a monotypic genus, four additional species have since been described. Leiurus abdullahbayrami (previously identified as L. quinquestriatus in Turkey) was classified as a new Leiurus species. This is the first report conducted on the lethality and biologic effects of L. abdullahbayrami scorpion venom in mice. In this study, the electrophoretic protein pattern of its venom was also determined. Two protein bands with molecular masses of 4 and 6 kDa were more strongly detected than other protein bands in the venom sample. Electrophoresis showed that L. abdullahbayrami scorpion venom possesses both short- and long-chain neurotoxins. The median lethal dose of this venom was found to be 0.19 mg/kg by subcutaneous (SC) injection in mice. Animals experimentally envenomed with L. abdullahbayrami venom exhibited hyperexcitability, agitation, aggressive behavior, squeaking and fighting, tachypnea, weakness, convulsions, and death due to cardiac and respiratory failure. In further studies, the potency of antivenom should be investigated in relation to the scorpion venom. Molecular and pharmacological studies are also required to identify and characterize L. abdullahbayrami scorpion venom.

Embryotoxicity following repetitive maternal exposure to scorpion venom

Hmed,BN; Riadh,B; Serria,H; Kamel,J; Khaled,Z
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 Português
Relevância na Pesquisa
59.276055%
Although it is a frequent accident in a few countries, scorpion envenomation during pregnancy remains scarcely studied. In the present study, the effects of repetitive maternal exposure to Buthus occitanus tunetanus venom are investigated and its possible embryotoxic consequences on rats. Primigravid rats received a daily intraperitoneal dose of 1 mL/kg of saline solution or 300 µg/kg of crude scorpion venom, from the 7th to the 13th day of gestation. On the 21st day, the animals were deeply anesthetized using diethyl-ether. Then, blood was collected for chemical parameter analysis. Following euthanasia, morphometric measurements were carried out. The results showed a significant increase in maternal heart and lung absolute weights following venom treatment. However, the mean placental weight per rat was significantly diminished. Furthermore, blood urea concentration was higher in exposed rats (6.97 ± 0.62 mmol/L) than in those receiving saline solution (4.94 ± 0.90 mmol/L). Many organs of venom-treated rat fetuses (brain, liver, kidney and spleen) were smaller than those of controls. On the contrary, fetal lungs were significantly heavier in fetuses exposed to venom (3.2 ± 0.4 g) than in the others (3.0 ± 0.2 g). Subcutaneous blood clots...

A biodistribution study of Hemiscorpius lepturus scorpion venom and available polyclonal antivenom in rats

Seyedian,R; Jalali,A; Babaee,MH; Pipelzadeh,MH; Rezaee,S
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 Português
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The purpose of the present study was to investigate the biodistribution profile of the venom of Hemiscorpius lepturus, the most dangerous scorpion in Iran. Blood and tissue samples were taken at various predetermined intervals during a 400-minute period for the venom and a 360-minute period for the antivenom in rats. The radio-iodination was carried out using the chloramine-T method. The results showed that the descending order of venom uptake was skin, kidneys and intestine, respectively. The descending order of polyclonal antivenom uptake was kidneys, intestine, heart and lungs. The calculated pharmacokinetic parameters of the venom were Telimination half-life = 521.5 ± 12.6 minutes; Vd/F (apparent volume of distribution) = 14.9 ± 3.3 mL; clearance (CL/F, apparent total clearance of the drug from plasma) 0.02 ± 0.005 mL/minute and for the antivenom Telimination half-life = 113.7 ± 7.4 minutes; Vd/F = 13 ± 1.2 mL and CL/F 0.08 ± 0.01 mL/minute. The pharmacokinetics profile comparison of the venom with that of the antivenom shows that serotherapy may be more effective if administered within 2-4 hours following envenomation by H. lepturus.

Comparison between two methods of scorpion venom milking in Morocco

Oukkache,Naoual; Chgoury,Fatima; Lalaoui,Mekki; Cano,Alejandro Alagón; Ghalim,Noreddine
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 Português
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Background The present study compared two methods used successfully in a large-scale program for the collection of scorpion venoms, namely the milking of adult scorpions via manual and electrical stimulation. Results Our immunobiochemical characterizations clearly demonstrate that regularly applied electrical stimulation obtains scorpion venom more easily and, most importantly, in greater quantity. Qualitatively, the electrically collected venom showed lack of hemolymph contaminants such as hemocyanin. In contrast, manual obtainment of venom subjects scorpions to maximal trauma, leading to hemocyanin secretion. Our study highlighted the importance of reducing scorpion trauma during venom milking. Conclusions In conclusion, to produce high quality antivenom with specific antibodies, it is necessary to collect venom by the gentler electrical stimulation method.

General characterization of Tityus fasciolatus scorpion venom. Molecular identification of toxins and localization of linear B-cell epitopes

Mendes, T. M.; Guimaraes-Okamoto, P. T. C.; Machado-de-Avila, R. A.; Oliveira, D.; Melo, M. M.; Lobato, Z. I.; Kalapothakis, E.; Chavez-Olortegui, C.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 109-117
Português
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); This communication describes the general characteristics of the venom from the Brazilian scorpion Tityus fasciolatus, which is an endemic species found in the central Brazil (States of Goias and Minas Gerais), being responsible for sting accidents in this area. The soluble venom obtained from this scorpion is toxic to mice being the LD50 is 2.984 mg/kg (subcutaneally). SDS-PAGE of the soluble venom resulted in 10 fractions ranged in size from 6 to 10-80 kDa. Sheep were employed for anti-T. fasciolatus venom serum production. Western blotting analysis showed that most of these venom proteins are immunogenic. T. fasciolatus anti-venom revealed consistent cross-reactivity with venom antigens from Tityus serrulatus. Using known primers for T. serrulatus toxins, we have identified three toxins sequences from T. fasciolatus venom. Linear epitopes of these toxins were localized and fifty-five overlapping pentadecapeptides covering complete amino acid sequence of the three toxins were synthesized in cellulose membrane (spot-synthesis technique). The epitopes were located on the 3D structures and some important residues for structure/function were identified. (C) 2015 Elsevier Ltd. All rights reserved.

Mild reproductive effects of the Tityus bahiensis scorpion venom in rats

Dorce,Ana Leticia C; Dorce,Valquiria AC; Nencioni,Ana Leonor A
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 Português
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Background Scorpion envenoming is a public health problem in Brazil, where Tityus serrulatus and T. bahiensis are considered the most dangerous scorpions. They are well adapted to urbanized environments, and there is an increasing probability of human exposure to these venoms, including during pregnancy. Not much is known about the effects of prenatal exposure to the venom, and no information is available to aid in the rational treatment of victims stung during pregnancy. Thus, this study aimed to investigate whether venom from the scorpion T. bahiensis administered once to pregnant female rats at a dose that causes a moderate envenomation may lead to deleterious effects on the reproductive performance of the dams and on the development of their offspring. This is the first work demonstrating that T. bahiensis venom, when administered experimentally to rats, alters maternal reproductive performance and the morphological development of fetuses. The venom was given to dams on the 5th (GD5) or on the 10th (GD10) gestational day. After laparotomy, on GD21, fetuses and placentas were counted, weighed and externally analyzed. The corpora lutea were counted. The sex and vitality of fetuses were evaluated, and each litter was then randomly divided for visceral or skeletal analyses. Data were analyzed by ANOVA followed by the Tukey-Kramer test and Fisher's exact test. The significance level for all tests was set at p < 0.05. Results : GD5 group presented an increased number of pre-implantation losses. Weight gains in fetuses and placentas were observed in the GD5 and GD10 groups. Weights of the heart and lungs were elevated in GD5 and GD10 and liver weight in GD10. Conclusions : Moderate envenomation by T. bahiensis scorpion venom alters maternal reproductive performance and fetal development. However...