Mature Solid Teratoma of the Retroperitoneum Presenting as Sigmoid Colon Polyp with Lower Gastrointestinal Bleeding: A Case Report

Mature colonic teratomas are rare tumors and no case, to the best of our knowledge, has been reported from the African continent. In addition, some pedunculated teratomas in the colon have been treated by endoscopic polypectomy and classified as primary teratoma of the colon. We report a case of a distinct intra sigmoid pedunculated teratoma originating from the retroperitoneum of a 4-year-old African girl and we highlight the potential for misclassification of primary origin of endoscopically removed polypoid teratomas in the colon. CASE PRESENTATION: A 4-year-old black African female child who presented with abdominal pain and hematochezia. On clinical assessment, she was found to be anaemic and to have a sigmoid colon mass. At surgery, there was a mobile mass within the lumen of sigmoid colon and the mass was fixed to the retroperitoneum by a stalk of tissue. Pathologist's review of the resected sigmoid segment showed a pedunculated intra-sigmoid mass with the stalk traversing the wall of the colon. The mass was histologically proven a mature solid teratoma. CONCLUSION: This, to the best of our knowledge, is the first report of intra sigmoid teratoma from the African continent. It highlights the potential for misclassification of endoscopically resected colonic teratomas

Suppression of cardiomyocyte functions by ß-CTX isolated from the Thai king cobra (Ophiophagus hannah) venom via an alternative method

Beta-cardiotoxin (ß-CTX), the three-finger toxin isolated from king cobra (Ophiophagus hannah) venom, possesses ß-blocker activity as indicated by its negative chronotropy and its binding property to both ß-1 and ß-2 adrenergic receptors and has been proposed as a novel ß-blocker candidate. Previously, ß-CTX was isolated and purified by FPLC. Here, we present an alternative method to purify this toxin. In addition, we tested its cytotoxicity against different mammalian muscle cell types and determined the impact on cardiac function in isolated cardiac myocyte so as to provide insights into the pharmacological action of this protein. Methods: ß-CTX was isolated from the crude venom of the Thai king cobra using reverse-phased and cation exchange HPLC. In vitro cellular viability MTT assays were performed on mouse myoblast (C2C12), rat smooth muscle (A7r5), and rat cardiac myoblast (H9c2) cells. Cell shortening and calcium transient dynamics were recorded on isolated rat cardiac myocytes over a range of ß-CTX concentration. Results: Purified ß-CTX was recovered from crude venom (0.53% w/w). MTT assays revealed 50% cytotoxicity on A7r5 cells at 9.41 ± 1.14 µM (n = 3), but no cytotoxicity on C2C12 and H9c2 cells up to 114.09 µM. ß-CTX suppressed the extend of rat cardiac cell shortening in a dose-dependent manner; the half-maximal inhibition concentration was 95.97 ± 50.10 nM (n = 3). In addition, the rates of cell shortening and re-lengthening were decreased in ß-CTX treated myocytes concomitant with a prolongation of the intracellular calcium transient decay, indicating depression of cardiac contractility secondary to altered cardiac calcium homeostasis. Conclusion: We present an alternative purification method for ß-CTX from king cobra venom. We reveal cytotoxicity towards smooth muscle and depression of cardiac contractility by this protein. These data are useful to aid future development of pharmacological agents derived from ß-CTX.(AU)

Pseudotumor hemofílico. Reporte de caso / Hemophiliac Pseudotumor. Case report

Teniendo en cuenta la baja prevalencia del pseudotumor hemofílico en pacientes con hemofilia, consideramos de interés presentar los hallazgos en un niño de 13 años con uno localizado en la mandíbula. Caso clínico Se trata de un niño de 13 años de edad, con el antecedente de hemofilia tipo B, que consulta por una masa submandibular bilateral de crecimiento progresivo en 9 meses de evolución, dolorosa, la cual presentó ruptura espontánea con abundante sangrado y descompensación hemodinámica que requirió manejo en la unidad de cuidado intensivo y embolización de la arteria facial derecha. En el examen físico se observan masas submandibulares bilaterales, la del lado derecho con ulceración de fondo sanguinolento.

Occurrence of non-protein low molecular weight cardiotoxin in Indian King Cobra (Ophiophagus hannah) Cantor 1836, venom.

Pathophysiology due to snakebite is a combined effect of various actions of the complex venom constituents. Importance of protein toxins in snake envenomation is well known. The present investigation reports the existence of nonprotein/nonpetide low molecular weight toxin in Indian King Cobra venom, which plays an important role in envenomation consequences in experimental animal models. A group of non-peptidic toxins (OH-NPT1) was isolated from Indian King Cobra Ophiophagus hannah by thin layer chromatography and silica gel column chromatography. UV, IR, NMR and (ESI) TOF-MS studies characterized the OH-NPT1 as a mixture of aliphatic acids having molecular weights 256, 326 and 340Da. The minimum lethal dose of OH-NPT1 was found to be 2.5 microg/20g (iv) and 4microg/20g (ip) in male albino mice. The cardiotoxic property of OH-NPT1 was established through studies on isolated guinea pig heart and auricle preparations, ECG studies in albino rat and estimation of LDH1/LDH and CPK-MB/CPK ratio in Swiss albino mice. Commercial antiserum failed to neutralize the lethality and cardiotoxicity of the toxin. However, calcium and magnesium effectively neutralized the lethal action.

Hemolitic action of Naja naja atra cardiotoxin on erythrocytes from different animals

A comparative study on the sensitivity of erythrocytes from different vertebrate species (avian, mammalian and reptilian) to the hemolytic action caused by cardiotoxin isolated from Naja naja atra venom was carried out. Cardiotoxin was able to induce direct hemolysis in washed erythrocytes from several animals, except for llama. The EC50 values from hemolysis of the most sensitive (cat) and the most resistant (snake) animal varied approximately tenfold. According to the cell behavior, it was possible to characterize four types of behavior: The first was observed in cat, horse and human cells; the second in rat, rabbit and dog erythrocytes; and the third only in llama erythrocytes, which were resistant to cardiotoxin concentrations up to 300 æg/ml. Finally, avian and reptilian erythrocytes were more resistant to cardiotoxin III-induced hemolysis than those of the mammalian species.

Up-regulation of Bax and endonuclease G, and down-modulation of Bcl-X(L) involved in cardiotoxin III-induced apoptosis in K562 cells

Cardiotoxin III (CTX III), a basic polypeptide with 60 amino acid residues isolated from Naja naja atra venom, has been reported to have anticancer activity. CTX III-induced K562 cell apoptosis was confirmed by DNA fragmentation (DNA ladder, sub-G1 formation) and phosphatidylserine (PS) externalization with an IC50 value of 1.7 mug/ml at 48 h. A mechanistic analysis demonstrated that CTX III-induced apoptotic cell death was accompanied by up-regulation of both Bax and endonuclease G (Endo G), and downregulation of Bcl-X(L). CTX III had no effect on the levels of Bcl-2, Bid, XIAP survivin, and AIF proteins. CTX III treatment caused loss of the mitochondrial membrane potential (delta psi m), release of mitochondrial cytochrome c to the cytosol, and activation of both caspase-9 and -3. CTX III-induced apoptosis was significantly blocked by the broad-spectrum caspase inhibitor Z-VAD-FMK. However, CTX III did not generate reactive oxygen species (ROS) and antioxidants, including N-acetylcysteine and catalase, did not block CTX III-induced apoptosis in K562 cells. Modulation of Bax, Bcl-X(L), and the Endo G proteins, release of mitochondrial cytochome c, and activation of caspase-3 and -9 all are involved in the CTX III-triggered apoptotic process in human leukemia K562 cells.

Actividad microbicida de la ribonucleasa y desoxirribonucleasa en cepas de bacterias patógenas in vitro / Microbicidal activity of ribonuclease and deoxyribonuclease in pathogenic bacterias strains in vitro

Las nucleasas son enzimas que por muchos años se han relacionado exclusivamente con la actividad digestiva. Sin embargo, diversos estudios han demostrado que en condiciones naturales, tienen una función microbicida importante. El presente trabajo se desarrolló con el objetivo de demostrar in vitro la acción germicida de la ribonuclease (RNasa) y la desoxirribonucleasa (DNasa) cuando se aplican exógenamente en algunas cepas patógenas. Surge como una necesidad de analizar la acción directa de las nucleasas sobre ciertos microorganismos, debido a que al aplicarse terapéuticamente en pacientes afectados de procesos infecciosos producidos por estos microorganismos, se ha obtenido el control del padecimiento. En cultivos de cepas puras de Staphylococcus, Proteus vulgaris, proteus mirabilis, Klebsiella pneumoniase, Pseudomonas aeruginosa, Salmonella typhi y Escherichia coli, se aplicaron directamente al medio de cultivo soluciones al 0.1, 1, 10, 25, 50, y 75 por ciento de RNasa (0.00070 mg/mL) y/o DNasa (0.00035 mg/mL). Se valoró la viabilidad y el crecimiento de las colonias bacterianas conservadas en condiciones óptimas de nutrición, temprana, pH y osmolaridad, a las 24, 48, 72 y 192 horas de exposición a estas nucleasas. Se observó que el efecto lítico se manifiesta en la mayor concentración y que las distintas cepas muestran una sensibilidad diferente a las enzimas, ya sea que se apliquen individualmente o en forma simultánea. Se concluye, que las nucleasas tienen actividad antimicrobiana selectiva in vitro, que corrobora el efecto que se ha observado in vivo, en donde además, de demostrar el efecto microbicida selectivo y lisar directamente a los microorganismos, controlan la infección porque destruyen a las células infectadas e inhiben la replicación de los microorganismos que se mantienen en el interior de algunas células.

Comparison of refolding patterns of erabutoxin b and cardiotoxin 3.10.2 from snake venom.

The refolding patterns of erabutoxin b (a neurotoxin) and cardiotoxin 3.10.2 (from Naja naja siamensis venom) have been studied by reducing both the proteins by treatment with reduced dithiothreitol followed by renaturation by treatment with oxidised dithiothreitol. Isoelectric focusing of the samples trapped at varying time intervals during renaturation of the proteins reveals formation of intermediates in the folding pathway with cardiotoxin 3.10.2. having fewer intermediates than erabutoxin b and faster rate of refolding (1 hr and 3 hr respectively).

Actividad hemolítica de venenos de serpientes de los géneros Bothrops, Lachesis, Crotalus y Micrurus (Serpentes: Viperidae y Elapidae) / Haemolytic activity of venoms from snakes of the genera Bothrop, Lachesis, Crotalus and Micrurus (Serpentes: Viperidae and Elapidae)

Hemolytic activity of eight Peruvian snake venoms from the families Viperidae and Elapidae (Bothrops atrox, B. pictus, B. hyoprorus, B. bilineatus, B. neuwedii, Lachesis m. muta, Crotalus d. terrificus, Microrus tschudi), and three Brazilian viperids (B. jararacussu, B. alternatus and C. d. collilineatus) is described. None of the venoms cause direct lysis on washed human erythrocytes. However, all of then caused indirect hemolysis provided that the incubation medium contains an exogenous source of lecithin. Venom of Micrurus tschudi was the most hemolytic (HD50 2.8 ug/ml) while that of B. bilineatus was the least (HD50 681.3 ug/ml). Only six of eleven venoms showed parallel curves of hemolytic activity, and the HD50 varied from 198 to 681 ug/ml and the following decreasing order of hemolytic activity was obtained: L. muta, C. d. terrificus, C. d. collilineatus, B. hyoprorus, B. bilineatus, B. alternatus

In vitro cytotoxicity of Rhodnius prolixus hemolytic factor and mellitin towards different trypanosomatids

Trypanosoma cruzi strain Y and clone Dm28c and other trypanosomatids were exposed to two lytic agents, Rhodnius prolixus hemolytic factor (RHF) and mellitin, in vitro. In both cases, the result was a significant decrease in the number of parasites after a 30-min treatment at 37-C. RHF and mellitin had distinct activities on differente strains and species of trypanosomatids. These observations suggest that RHF may be an important factor in selecting resistant strains of trypanosomes for development in the vector's gut