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1.
Microb Cell ; 3(1): 14-28, 2015 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-28357313

RESUMO

The protozoan parasite Leishmania causes a variety of sicknesses with different clinical manifestations known as leishmaniasis. The chemotherapy currently in use is not adequate because of their side effects, resistance occurrence, and recurrences. Investigations looking for new targets or new active molecules focus mainly on the disruption of parasite specific pathways. In this sense, ergosterol biosynthesis is one of the most attractive because it does not occur in mammals. Here, we report the synthesis of ergosterone coupled molecules and the characterization of their biological activity on Leishmania mexicana promastigotes. Molecule synthesis involved three steps: ergosterone formation using Jones oxidation, synthesis of Girard reagents, and coupling reaction. All compounds were obtained in good yield and high purity. Results show that ergosterone-triazol molecules (Erg-GTr and Erg-GTr2) exhibit an antiproliferative effect in low micromolar range with a selectivity index ~10 when compared to human dermic fibroblasts. Addition of Erg-GTr or Erg-GTr2 to parasites led to a rapid [Ca2+]cyt increase and acidocalcisomes alkalinization, indicating that Ca2+ was released from this organelle. Evaluation of cell death markers revealed some apoptosis-like indicators, as phosphatidylserine exposure, DNA damage, and cytosolic vacuolization and autophagy exacerbation. Furthermore, mitochondrion hyperpolarization and superoxide production increase were detected already 6 hours after drug addition, denoting that oxidative stress is implicated in triggering the observed phenotype. Taken together our results indicate that ergosterone-triazol coupled molecules induce a regulated cell death process in the parasite and may represent starting point molecules in the search of new chemotherapeutic agents to combat leishmaniasis.

2.
Toxicon ; 59(5): 547-54, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22310207

RESUMO

A mouse model was established to reproduce the haemorrhagic syndrome which occurs in humans after accidental contact with the hairs of the caterpillar Lonomia achelous (LA) and measures the haemostatic and inflammatory alterations that occur as a result of this contact. Mice were injected intradermally with different doses (0.4, 0.8 and 1.6 mg/animal) of L. achelous haemolymph (LAH). Haematological (haemoglobin, haematocrit, platelet count, differential leukocyte count), haemostatic (fibrinogen, plasminogen, factor XIII [FXIII], fibrinolytic activity) and inflammatory parameters (tumour necrosis factor alpha [TNF-α], nitric oxide [NO]) were measured at different times up to 48 h. C57BL/6 mice responded to LAH injection, in terms of these parameters, in a manner similar to that seen in humans, whereas the BALB/c mice were unresponsive. In C57BL/6 mice injected with LAH, time course measurements showed: a) a reduction in the haemoglobin, haematocrit, fibrinogen, FXIII and plasminogen levels, b) no effect on the platelet count and c) immediate leukocytosis and an increase in the fibrinolytic activity in plasma. An inflammatory response (TNF-α) was observed within 1 h post-injection, followed by a more persistent increase in serum NO. These findings suggest that C57BL/6 mice represent a useful model of the haemorrhagic syndrome observed in humans who have suffered contact with the caterpillar, permitting a deeper understanding of the role of the inflammatory response in the haematological and haemostatic manifestations of this syndrome.


Assuntos
Venenos de Artrópodes/toxicidade , Hemolinfa , Hemostasia/efeitos dos fármacos , Inflamação/etiologia , Mariposas , Animais , Fibrinogênio/análise , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Modelos Animais , Fator de Necrose Tumoral alfa/sangue
3.
Asian Pac J Trop Biomed ; 1(4): 279-84, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23569775

RESUMO

OBJECTIVE: To investigate the bioecological relationship between Chagas disease peridomestic vectors and reptiles as source of feeding. METHODS: In a three-story building, triatomines were captured by direct search and electric vacuum cleaner search in and outside the building. Then, age structure of the captured Triatoma maculata (T. maculata) were identified and recorded. Reptiles living in sympatric with the triatomines were also searched. RESULTS: T. maculata were found living sympatric with geckos (Thecadactylus rapicauda) and they bit residents of the apartment building in study. A total of 1 448 individuals of T. maculata were captured within three days, of which 74.2% (1 074 eggs) were eggs, 21.5% were nymphs at different stages, and 4.3% were adults. CONCLUSIONS: The association of T. maculata and T. rapicauda is an effective strategy of colonizing dwellings located in the vicinity of the habitat where both species are present; and therefore, could have implications of high importance in the intradomiciliary transmission of Chagas disease.


Assuntos
Cordados/parasitologia , Ecossistema , Triatoma/crescimento & desenvolvimento , Trypanosoma cruzi/isolamento & purificação , Adulto , Animais , Doença de Chagas/transmissão , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Répteis/parasitologia , Venezuela
4.
Ann Hematol ; 86(12): 879-85, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17891398

RESUMO

The haemostatic components of venom from the genus Porthidium has been poorly studied, although it is known that severe manifestations occur when humans are envenomed, which include invasive oedema and disseminated ecchymosis. The effects of venom on blood platelets are commonly studied and are normally carried out with platelet-rich plasma (PRP). A series of crude venom dilutions was used to determine the effects of adenosine diphosphate (2 microM) and adrenaline (11 microM) induced platelet aggregation. Venom of Porthidium lansbergii hutmanni was fractioned by anionic exchange chromatography, and the fractions were also used to determine the 50% inhibition of adenosine diphosphate (ADP) and adrenaline-induced platelet aggregating dose (AD50). Crude venom has more effect in inhibiting adrenaline-induced aggregation (AD50 = 0.0043 microg) followed by the adenosine diphosphate (AD50 = 17 microg). Peaks I and II obtained by chromatography also inhibited adrenaline-induced platelet aggregation with an AD50 of 3.2 and 0.013 microg, respectively, and both peaks inhibited ADP-induced platelet aggregation with an AD50 of 10 microg. The main purpose of this work was to characterise the in vitro effects caused by P. lansbergii hutmanni crude venom and its fractions on the platelet aggregation mediated by adrenaline and ADP agonists.


Assuntos
Venenos de Crotalídeos/farmacologia , Fibrinolíticos/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Difosfato de Adenosina/antagonistas & inibidores , Difosfato de Adenosina/farmacologia , Animais , Cromatografia por Troca Iônica , Venenos de Crotalídeos/química , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Epinefrina/farmacologia , Fibrinolíticos/isolamento & purificação , Humanos , Inibidores da Agregação Plaquetária/isolamento & purificação , Especificidade da Espécie
5.
Arch. venez. farmacol. ter ; 25(1): 6-10, 2006. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-517128

RESUMO

El veneno de Apis mellífera es una mezcla compleja de compuestos por moléculas de alto y bajo peso molecular, enzimas y peptidos, de los cuales la fosfolipasa A2, melitina y apamina son los compuestos causantes de los accidentes fatales en el ser humano y mamíferos. Provocando además, daño local en el sitio de picadura y otos efectos graves, tales como reacciones sistémicas. La toxicidad del veneno de abeja, sobre los humanos, no se conoce con exactitud, la dosis letal 50 en ratones, del veneno liofilizado y purificado es de 2.5 a 2.8 mg/kg por vía endovenosa y la dosis letal es de 6 mg/kg por vía endovenosa. Cuando una abeja pica, inyecta de 50 a 100 µg de veneno. Los efectos tóxicos de la picadura son provocados inmediatamente, el inicio de la anaflaxis es típico y rápido, desencadenado minutos después de la picadura. La enfermedad del suero puede ocurrir 10 a 14 días después del accidente. Cien picaduras pueden ser necesarias para matar a un humano, auqnue hay otros casos donde una picadura puede provocar la muerte y otras que han picado 400 ó más y han sobrevivido.


Assuntos
Apamina , Venenos de Abelha , Meliteno , Fosfolipases A , Toxicologia
6.
Rev. Fac. Med. (Caracas) ; 28(1): 12-16, 2005. ilus
Artigo em Espanhol | LILACS | ID: lil-422051

RESUMO

El conjunto de signos y síntomas cardiotóxicos, tales como taquicardia, bradicardia, trastornos del ritmo, que se describen en algunos pacientes envenenados por C. d. cumanensis, hace pensar, que existe actividad del veneno sobre las estructuras cardíacas. El veneno total del cascabel crótalus durissus cumanensis, procedente de Caruachi, estado Bolívar presentó una DL50 de 0,140 mg/Kg de peso. Los resultados de microscopia electrónica reportaron en las primeras 6 horas desorganización, pérdida del sistema contráctil y sistema sarcotubular hinchado. Capilares con abundantes prolongaciones y la luz parcialmente ocluida, el grosor de la pared endotelial fue variable con una notable disminución de vesículas pinocíticas y cavéolas, las mitocondrias hinchadas y degeneradas. A las 24 horas se observarón áreas con fibrillas contraídas, áreas de necrosis, por pérdida de la membrana plasmática. A las 48 horas los capilares se mostraron ocluidos, con aumento en el grosor de la pared, ruptura de la pared de la célula muscular, mitocondrias degeneradas y un aumento marcado de polisomas libres. Se apreció infiltrado de macrófagos. El objetivo de este trabajo se basa en describir por primera vez en la literatura, las alteraciones ultraestructurales del músculo cardíaco de ratones tratados con veneno crudo de crótalus durissus cumanensis


Assuntos
Humanos , Animais , Crotalus , Traumatismos Cardíacos , Venenos de Serpentes , Medicina Tropical , Venezuela
7.
Rev. Fac. Med. (Caracas) ; 28(1): 40-49, 2005.
Artigo em Inglês | LILACS | ID: lil-422056

RESUMO

En diciembre de 1997, CONTRASIDA (Organización No-Gubernamental) tomó un paso histórico en la lucha contra el Sida en Venezuela al intoducir el condón femenino. Un grupo particularmente en riesgo para la infección con virus de inmunodeficiencia humana (HIV), y susceptible de infectar otros con el HIV es el grupo de las trabajadoras sexuales (FCSWS). Teniendo múltiples compañeros, quienes frecuentemente rehúsan usar un método de barrera, así las FCSWS están en gran riesgo para adquirir la infección. Además, como el HIV no puede detectarse dentro de los 3-6 meses de adquirir la infección, estas mismas FCSWS puede inconscientemente infectar sus clientes, quienes a su vez pueden infectar a sus esposas y/o compañeras (os). Esto últimmo es lo que se denomina "la teoría sexual de red": gente conectada por sus contactos sexuales, y por lo tanto forma la llamada "modelos de redes sexuales". CONTRASIDA elaboró un cuestionario e implementó un proyecto de información que alcanzó 1.000 mujeres, la mayoría FCSWS en Venezuela. Dentro del marco de la "teoría sexual de red" CONTRASIDA incluyó también clientes/compañeros de FCSWS en los cursillos sobre el condón femenino. Además, organizó cursillos especiales para ama de casas, estudiantes y profesionales femeninos que participaron en el proyecto, como un instrumento efectivo en la lucha contra el HIV y otras enfermedades de transmisión sexual


Assuntos
Adulto , Humanos , Feminino , Síndrome da Imunodeficiência Adquirida , Controle de Doenças Transmissíveis , Preservativos , HIV , Infecções Sexualmente Transmissíveis , Medicina , Venezuela
8.
J Submicrosc Cytol Pathol ; 36(1): 91-6, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15311679

RESUMO

Biopsy specimens of cervico-scutular muscles obtained from animals injected with bee crude venom were prepared for electron microscopy studies. At 6 h from Apis mellifera venom injection, in mice under transmission electron microscopy, the muscular fibres presented different atrophy levels with increment of the intermyofibrillar spaces. Tubules and sarcoplasmic reticulum elements were altered, in some places only tubular fragments and an increment of the intermyofibrillar spaces were noticed as well as loss of fibre regularity and prominent triads. In subsarcolemma region, areas lacking myofibrils and mitochondria damages were observed. Muscular segmental necrosis and atrophy areas were observed. Neuromuscular junctions were altered. The number of synaptic vesicles was very variable and synaptic clefts showed irregularities. A decrease in the number and arrangement of the synaptic clefts, as well as free polysomes, suggesting regeneration processes, were also observed. The myelinic nerves exhibited in the axon or in the wall vacuolisation areas. The presence of severe muscular lesions, the finding of venom activities in the presynaptic region and the detection of damages in the neuromuscular junctions at different chronological stages of our experiments indicate that the bee venom is highly toxic for neuromuscular structures.


Assuntos
Venenos de Abelha/toxicidade , Abelhas , Músculo Esquelético/efeitos dos fármacos , Junção Neuromuscular/efeitos dos fármacos , Nervos Periféricos/efeitos dos fármacos , Animais , Venenos de Abelha/administração & dosagem , Injeções Intraperitoneais , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/ultraestrutura , Músculo Esquelético/ultraestrutura , Junção Neuromuscular/ultraestrutura , Nervos Periféricos/ultraestrutura
9.
Vet Hum Toxicol ; 46(1): 10-4, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14748408

RESUMO

Many colubrid snakes produce toxic oral secretions. We studied venom (Duvernoy's gland secretion) collected from Venezuelan opisthoglyphous (rear-fanged) colubrid snakes. Different proteins were present in Thamnodynastes stigilis Duvernoy's gland secretion and were characterized by 20% SDS-PAGE protein electrophoresis. The venom displayed proteolytic (gelatinase) activity that was partially purified on a chromatography ionic exchange mono Q2 column. We demonstrated hemorrhagic activity of Thamnodynastes stigilis Duvernoy's gland secretion on chicken embryos and mouse skin and peritoneum. Mice inoculated with Thamnodynastes stigilis Duvernoy's gland secretion presented signs of neurotoxicity. Thamnodynastes stigilis Duvernoy's gland secretion had proteolytic, hemorrhagic, and neurotoxic activities, not previously described in this species and identifies the presence of a new venomous colubrid in Venezuela.


Assuntos
Colubridae , Hemorragia/induzido quimicamente , Venenos de Serpentes/toxicidade , Animais , Embrião de Galinha/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Gelatinases/efeitos dos fármacos , Dose Letal Mediana , Masculino , Camundongos , Peritônio/efeitos dos fármacos , Pele/efeitos dos fármacos
10.
Roum Arch Microbiol Immunol ; 63(3-4): 245-52, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17240793

RESUMO

This paper considers the effect of social and cultural factors on malaria spreading in rural Venezuela. It argues that standard vertical malaria control programs are inclined to ignore local workplace and living conditions instead of recruiting traditional practices into the planning scenario for more effective malaria control. An epidemiological survey on people migrating from malaria endemic areas to non-endemic region studied by blood films and a Plasmodium falciparum in vivo test. The results of the survey on people migrating from malaria endemic areas to non endemic regions revealed that 138 (118 males and 20 females) (23.3%) had fever (38.2-39 degrees C), malarial parasites were detected in the blood films of 49 (35.5%) from 138 febrile (parasitaemic) patients, and 45 (91.8%) of the parasitaemic cases were infected with P. falciparum; other four cases carried P. vivax only. Differences in prevalence, parasites load and the density of infection were observed between the three age groups. The asexual parasite load and the density of parasites (asexual and sexual forms) were appreciably higher in older children than in the other two age-groups (P < 0.001 for each). In the Plasmodium falciparum in vivo test, nine (22.5%) patients presented resistance grade III. People with transient jobs in malaria endemic areas could transport the parasites to non-endemic areas establishing a new malaria focus during seasonal migration activities.


Assuntos
Malária/epidemiologia , Saúde da População Rural , População Rural , Viagem , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Malária/transmissão , Masculino , Estações do Ano , Venezuela/epidemiologia
11.
Rev. Fac. Med. (Caracas) ; 27(2): 106-110, 2004. tab
Artigo em Inglês | LILACS | ID: lil-421209

RESUMO

Fueron estudiados retrospectivamente ciento cincuenta y ocho pacientes mordidos por serpientes venenosas en las historias médicas del Hospital Manuel Nuñez Tovar del estado Monagas, Venezuela desde enero de 1990 hasta diciembre de 1999. La mayoría de estos pacientes fueron trabajadores rurales: 124 (78 por ciento) hombres y 34 (22 por ciento) mujeres, en edades desde 1 hasta más de 60 años. Ciento cinco (67 por ciento) pacientes fueron diagnósticados con mordedura de serpientes del género Bothrops y 53 (33 por ciento) por Crotalus. Ciento veinte y un (76 por ciento) fueron mordidos en las piernas y 37 (24 por ciento) en los brazos. Los meses de enero, abril, mayo, septiembre, octubre, noviembre y diciembre fueron los de mayor incidencia para el envenenamiento bothrópico mientras en envenenamiento crotálico fue mayor en los meses de marzo, agosto y diciembre. Este trabajo mostró que la prevalencia del envenenamiento crotálico fue muy alta en comparación con otros estados del país. Estudios adicionales de epidemiología prospectiva serán necesarios para un mejor entendimiento de los hallazgos observados en este trabajo


Assuntos
Mordeduras de Serpentes , Venenos de Serpentes , Serpentes , Viperidae , Medicina Tropical , Venezuela
12.
Rev. Fac. Med. (Caracas) ; 27(1): 25-28, 2004. tab
Artigo em Inglês | LILACS | ID: lil-406105

RESUMO

Se estudia retrospectivamente los aspectos clínicos y epidemiológicos de los pacientes con mordeduras de serpientes en el Estado Bolívar, Venezuela. Se revisaron los expedientes de 284 pacientes del Hospital Universitario "Ruíz y Páez" en Ciudad Bolívar, Venezuela, desde enero 1990 hasta diciembre 1999 que sufrieron mordeduras de serpientes. La mayoría de estos pacientes fueron trabajadores rurales, 155 (76,4) hombres y 48 (23,6 por ciento) mujeres, con edades entre un año y mayores de sesenta años. Ciento cuatro (51,7 por ciento) pacientes fueron mordidos por serpientes del genero Bothrops, 75 (37,0 por ciento) por Crotalus y 23 (11,3 por ciento) por Lachesis. Cientoveinticuatro (86,2 por ciento) fueron mordidos en las piernas y 28 (13,8 por ciento) en el brazo. De enero a noviembre fueron los meses de mayor incidencia de envenamientos botrópicos, mientras los envenenamientos crotálicos fueron de junio a diciembre. Los envenenamientos lachésicos fueron de octubre a diciembre. Este estudio mostró que la prevalencia de envenenamientos crotálicos en el estado Bolívar fue más elevado que en otra región de Venezuela. promover estudios epidemiológicos prospectivos será necesario para una mejor comprensión de estas conclusiones


Assuntos
Humanos , Masculino , Feminino , Estudos Epidemiológicos , População Rural , Mordeduras de Serpentes , Medicina Tropical , Venezuela
13.
J Submicrosc Cytol Pathol ; 35(3): 309-14, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14690180

RESUMO

Bee accidents incidence is underestimated because many people do not consult to the physicians. Here it is described for the first time the severe mice adrenal gland damage induced by Apis mellifera venom. Biopsy specimens were obtained from mice adrenal gland and after sample preparation observed in Hitachi H-7100 electron microscope. In this work the ultrastructural analysis showed, 6 h after injection, a non homogeneous smooth endothelial reticulum, and in some places loss of plasma membrane. The fenestrae spaces were bigger and detritus in the capillary lumen were observed. Erythrocytes were seen in a cortical cell. After 48 h of venom injection, expanded fenestrae were observed. Capillary basal membrane was interrupted. Myelin-like figures and autophagic vacuoles were noticed. Swollen smooth endoplasmic reticulum elements and endothelial unfolding to the light were seen. Moreover, swollen Golgi and mitochondria were observed, in some places forming myelinic-like figures. At 144 h after venom injection, widened spaces were noticed in capillary fenestrae. Cellular section showed swollen and lost smooth endoplasmic reticulum elements. Smooth endoplasmic reticulum tubules disappearance suggested non steroidogenesis. In conclusion, we suggest that some of the bee envenoming human clinical manifestations, as is observed in mice, are determined by suprarenal gland damage produced by toxins present in this venom.


Assuntos
Córtex Suprarrenal/efeitos dos fármacos , Venenos de Abelha/toxicidade , Abelhas , Córtex Suprarrenal/ultraestrutura , Animais , Abelhas/fisiologia , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Organelas/efeitos dos fármacos , Organelas/ultraestrutura
14.
Rev. Fac. Med. (Caracas) ; 26(2): 100-104, jul.-dic. 2003. tab
Artigo em Inglês | LILACS | ID: lil-406463

RESUMO

Fueron estudiados retrospectivamente ciento cincuenta y ocho pacientes mordidos por serpientes venenosas en las historias médicas del Hospital Manuel Nuñez Tovar del estado Monagas, Venezuela desde enero de 1990 hasta diciembre 1999. La mayoría de estos pacientes fueron trabajadores rurales: 124 (78 por ciento) hombres y 34 (22 por ciento) mujeres, en edades desde 1 hasta mas de 60 años. Ciento cinco (67 por ciento) pacientes fueron diagnosticados con mordedura de serpientes del género Bothrops y 53 (33 por ciento) por Crotalus. Ciento veinte y un (76 por ciento) fueron mordidos en las piernas y 37 (24 por ciento) en los brazos. Los meses de enero, abril, mayo, septiembre, octubre noviembre y diciembre fueron los de mayor incidencia para el envenenamiento bothrópico, mientras el envenenamiento crotálico fue mayor en los meses de marzo, agosto y diciembre. Este trabajo mostró que la prevalencia del envenenamiento crotálico fue muy alta en comparación con otros estados del país. Estudios adicionales en epidemiología prospectiva serán necesarios para un mejor entendimiento de los hallazgos observados en este trabajo


Assuntos
Masculino , Feminino , Braço , Crotalus , Perna (Membro) , Estudos Retrospectivos , Mordeduras de Serpentes , Viperidae , Medicina , Venezuela
15.
Rev. toxicol ; 20(3): 199-203, sept.-dic. 2003. tab, ilus
Artigo em Es | IBECS | ID: ibc-28969

RESUMO

Las actividades tóxicas y enzimáticas del veneno de serpiente mapanare (Bothrops colombiensis), cuya acción abarca casi todos los tejidos de mamíferos, no han sido estudiadas, estructural o ultraestructuralmente de manera exhaustiva, en el Sistema Nervioso Central (SNC).Se inocularon ratones adultos C57/Bl por vía endovenosa con concentraciones de veneno de 0,25 mg/kg de peso. Se sacrificaron a las 24 horas después de la inoculación de veneno y se hizo extracción del encéfalo, se fijó inmediatamente con paraformaldehído y se realizaron cortes vértico-tranversales, tomando áreas representativas de corteza cerebral y cerebelosa, asta de Amón, núcleos grises basales y tallo encefálico. Se prepararon para estudio de histología convencional (hematoxilina y eosina) y para microscopía electrónica, en un equipo de transmisión Hitachi HS-500. A1 extraer el encéfalo y hacer cortes coronales no se observaron lesiones macroscópicas, a pesar de verse intensa hemorragia en las áreas dérmicas. A la microscopía óptica, los cerebros de ratones mostraron eritrocitos extravasados en las leptomeninges y pericapilares, en los núcleos grises centrales, así como ligera espongiosis subpial, pericapilar y en el neuropilo. En el ámbito ultrastructural, las células endoteliales de los capilares corticales se encontraban tumefactas con algunas vesículas de pinocitosis en la superficie luminal, la luz capilar ocluida y mitocondrias hinchadas. Además se observó tumefacción de las prolongaciones astrogliales pericapilares. El endotelio de los capilares de los plexos coroideos mostró algunas figuras mielínicas citoplasmáticas y engrosamiento de la membrana basal.En conclusión, la actividad del veneno de Bothrops colombiensis no fue de la intensidad que se observa en otros tejidos del organismo, probablemente por el efecto protector de la barrera hematoencefálica, que pudiera bloquear la acción de muchos componentes tóxicos y enzimáticos del veneno. Este hecho es observado en pacientes humanos mordidos por serpientes de esta especie, donde los hallazgos de daño del SNC son escasos (AU)


Assuntos
Animais , Camundongos , Mordeduras de Serpentes/diagnóstico , Venenos de Serpentes/efeitos adversos , Venenos de Serpentes/toxicidade , Hematoxilina/análise , Hematoxilina/efeitos adversos , Hematoxilina/toxicidade , Tecido Nervoso/fisiopatologia , Tecido Nervoso/patologia , Microscopia Eletrônica/métodos , Microscopia Eletrônica , Hemorragia/complicações , Hemorragia/diagnóstico , Hemorragia/etiologia , Peptídeo Hidrolases/análise , Peptídeo Hidrolases/efeitos adversos , Peptídeo Hidrolases/toxicidade , Colagenases/análise , Colagenases/toxicidade
16.
Mycoses ; 45(1-2): 19-21, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11856432

RESUMO

The susceptibility to Crotalus venom of 14 yeast and 10 mould fungal isolates was assessed. This venom was tested in a standardized well diffusion test, using 400 microg/20 microl well. The percentage of susceptibility to yeast isolates was 78.6% (> 8 mm); that for filamentous isolates was 50% (> 8 mm).


Assuntos
Antifúngicos/farmacologia , Venenos de Crotalídeos/farmacologia , Crotalus , Fungos/efeitos dos fármacos , Animais , Humanos , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/efeitos dos fármacos , Leveduras/efeitos dos fármacos
17.
J Submicrosc Cytol Pathol ; 34(4): 447-59, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12575843

RESUMO

Acute renal insufficiency related to acute tubular necrosis is the most important complication caused by crotalid bite. For structural and ultrastructural studies of renal tissue, mice injected with crude venom or C. vegrandis haemorrhagic fraction, and controls were tested. Light microscopy analysis of kidneys at 24 h after injection of crude venom showed only moderate alterations such as tubular epithelia microvacuolisation. After 120 h marked glomerular and tubular capillaries congestion and interstitial oedema were observed. At 24 h after Uracoina-1 i.p. injection, intense glomerular and peritubular capillaries congestion was observed. Electron microscopic analysis of kidneys 24 h after i.p. injection of crude venom showed, capillary endothelial cell debris and pleomorphic mitochondria. Loss of interdigitations regularity, abundant dense bodies and light widening of the basal membrane were observed. Autophagic vacuoles were present as well as endothelia unfolding to the lumen and altered forms of podocytes. At 48 h, augmented endothelia without fenestrae formation with sequestration of low optical density debris inside the protrusions were noticed. At 120 h, capillary residues with loss of the endothelium were present and the basal membrane was widened. At 15 days, the number of vesicles and vacuoles in the tubules was increased and only few interdigitations were noticed. Autophagic vacuoles and mitochondrial matrix low electron density were observed. At 120 h after injection of crude venom, vascular damage with loss of capillary cell structures and collagen fibres were observed. At 24 h of haemorrhagic fraction injection, presence of autophagic vacuoles and myelinic figures were noticed.


Assuntos
Venenos de Crotalídeos/toxicidade , Crotalus , Rim/efeitos dos fármacos , Animais , Capilares/efeitos dos fármacos , Capilares/ultraestrutura , Venenos de Crotalídeos/administração & dosagem , Venenos de Crotalídeos/isolamento & purificação , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/patologia , Injeções Intraperitoneais , Rim/patologia , Glomérulos Renais/irrigação sanguínea , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/ultraestrutura , Túbulos Renais/irrigação sanguínea , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/ultraestrutura , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos , Ratos , Ratos Sprague-Dawley
18.
Biochim Biophys Acta ; 1548(1): 57-65, 2001 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-11451438

RESUMO

Uracoan rattlesnake (Crotalus vegrandis) venom was subjected to chromatographic, electrophoretic, biochemical and in vivo haemorrhagic analysis. A haemorrhagic toxin (Uracoina-1) active on skin at the site of inoculation in mice was purified by Mono Q2 anion-exchange chromatography and size exclusion (SE) high-performance liquid chromatography. The purified preparation was a protein of M(r) 58,000 as revealed by sodium dodecyl sulphate--polyacrylamide gel electrophoresis under denatured conditions and with silver staining. The use of EDTA, EGTA and 1,10-phenanthroline inhibited haemorrhagic and proteolytic activities. Inhibitors of serine proteinases such as PMSF and TCLK had no effect on the haemorrhagic fraction. Uracoina-1 hydrolyses casein, hide powder azure and fibrinogen have an optimal pH of 8.2. It rapidly digests the A alpha-chain of fibrinogen. Thermal denaturation of Uracoina-1 after exposure at 60 degrees C for 15 min led to inactivation of the haemorrhagic activity. In addition, Uracoina-1 is myotoxic, lacking haemolytic, defibrinating and lethal effects. The N-terminal amino acid sequence (20 residues) was determined.


Assuntos
Venenos de Crotalídeos/química , Venenos de Crotalídeos/isolamento & purificação , Proteínas/isolamento & purificação , Viperidae , Sequência de Aminoácidos , Animais , Fracionamento Químico , Cromatografia por Troca Iônica , Creatina Quinase/sangue , Venenos de Crotalídeos/antagonistas & inibidores , Venenos de Crotalídeos/farmacologia , Venenos de Crotalídeos/toxicidade , Crotalus , Eletroforese em Gel de Poliacrilamida , Inibidores Enzimáticos/farmacologia , Hemorragia/induzido quimicamente , Concentração de Íons de Hidrogênio , Injeções Intradérmicas , Injeções Intramusculares , Masculino , Camundongos , Dados de Sequência Molecular , Doenças Musculares/sangue , Doenças Musculares/induzido quimicamente , Proteínas/antagonistas & inibidores , Proteínas/farmacologia , Pele/efeitos dos fármacos
19.
J Nat Toxins ; 10(2): 91-7, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11405280

RESUMO

The main aim of this work was the development of a primary hepatocyte culture from Didelphis marsupialis, to determine the possible use of culture medium supernatants as a source of inhibitors of the Bothrops lanceolatus venom hemorrhagic activity. The cellular culture was carried out from isolated hepatocytes by the double perfusion technique, and digestion of the liver with collagenase and culturing the hepatocytes in a liquid media under continuous agitation at 37 degrees C in 5% CO2. The hemorrhagic activity inhibition assays were performed inoculating intradermically, a mixture of Bothrops lanceolatus venom plus a pool of liver spheroids culture supernatants, in mice. These liver Didelphis marsupialis spheroid cultures were adequate to obtain large supernatant volumes with inhibitors of hemorrhagic activity.


Assuntos
Venenos de Crotalídeos/efeitos adversos , Venenos de Crotalídeos/antagonistas & inibidores , Hepatócitos/fisiologia , Fígado/química , Gambás/fisiologia , Animais , Bioensaio , Técnicas de Cultura de Células , Meios de Cultura , Hemorragia/etiologia , Masculino , Camundongos , Esferoides Celulares
20.
Rev. Fac. Med. (Caracas) ; 24(1): 88-92, ene.-jun. 2001. tab
Artigo em Espanhol | LILACS | ID: lil-327339

RESUMO

La zona minera en estudio presenta una alta población flotante, que vive de la actividad minera extractiva rudimentaria, basado en motores hidráulicos y batea, afectando de manera irreversible al paisajismo y contaminando el medio ambiente físico, social, sanitario y económico. A través de la aplicación de la investigación-acción, refiriendo las características generales de la zona dentro del marco de la salud ambiental, la actividad económica local, el individuo y sus relaciones sociales, médico-asistenciales, y de calidad de vida se realizó un estudio etnográfico de la población, el cual describe el patrón de asentamiento local, permitiendo poner en práctica técnicas de evaluación cualitativa validadas a posteriori con técnicas de evaluación cuantitativa. El trabajo de campo en una primera fase permitió el conocimiento e interrelación con la comunidad a fin de sensibilizarla hacia la investigación, en una segunda fase la definición de la muestra seleccionada para la realización de exámenes clínicos y paraclínicos con la toma de datos epidemiológicos y, una tercera fase de entrega de resultados médicos y tratamientos específicos, acompañada de la entrega de conclusiones a la comunidad. El análisis epidemiológico permite describir la prevalencia de enfermedades de transmisión sexual, su interrelación con el ambiente y el modelo de desarrollo predominante. Una vez que se ha logrado la integración de los datos se concluye las claras relaciones de la triada ecológica entre el individuo, el agente y el ambiente local, llegando a la necesidad de hacer planteamientos acerca de políticas de desarrollo en la zona


Assuntos
Humanos , Masculino , Feminino , Ouro , Ecologia Humana , Mineração , Infecções Sexualmente Transmissíveis , Venezuela
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