RESUMEN
Toxin phospholipases-D present in the venom of Loxosceles spiders is the principal responsible for local and systemic effects observed in the loxoscelism. In this study, we describe the cloning, expression, functional evaluation, and potential biotechnological application of cDNAs, which code for two new phospholipase D isoforms, LIPLD1 and LIPLD2, of the spider Loxosceles laeta. The recombinant protein rLIPLD1 had hydrolytic activity on sphingomyelin and in vitro hemolytic activity on human red blood cells, whereas rLIPLD2 was inactive. The purified recombinant proteins and the venom are recognized by polyclonal anti-rLIPLD1 and rLIPLD2 sera produced in animals and conferred immunoprotection against the venom. These new isoforms reinforce the importance of the multigene family of phospholipases-D present in Loxosceles spiders. A highly immunogenic inactive isoform such as rLIPLD2 raises important expectation for its use as a potential immunogenic inducer of the immunoprotective response to the toxic action of the venom of Loxosceles laeta.
Asunto(s)
Biotecnología , Fosfolipasa D , Venenos de Araña/enzimología , Arañas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células Cultivadas , Clonación Molecular , Secuencia Conservada , ADN Complementario/genética , Eritrocitos/efectos de los fármacos , Hemólisis/efectos de los fármacos , Humanos , Isoenzimas , Datos de Secuencia Molecular , Fosfolipasa D/genética , Fosfolipasa D/inmunología , Fosfolipasa D/farmacología , Hidrolasas Diéster Fosfóricas/toxicidad , Filogenia , Alineación de Secuencia , Especificidad de la Especie , Venenos de Araña/toxicidad , Arañas/inmunología , Arañas/metabolismoRESUMEN
The venom of Loxosceles spiders produces severe dermonecrotic damage, intravascular hemolysis, systemic alterations and risk of death. Clostridium perfringens is present in the microbial flora of the fangs and venom glands of Loxosceles intermedia. Its inoculation with the venom may infect the wound site and exacerbate the dermonecrotic damage. This anaerobic bacterium is widely distributed in nature and capable of damage with similar characteristics and severity to the spider venom. In this study we isolated and characterized species of Clostridium from the fangs and venom glands of Loxosceles laeta, including C. perfringens. The sensitivity patterns of different isolates of C. perfringens were evaluated by minimum inhibitory concentration against penicillin, ampicillin, erythromycin, gentamicin, chloramphenicol, clindamycin and tetracycline, under anaerobic conditions, using the method of microdilution in broth. Strain C. perfringens H28 showed resistance to penicillin, ampicillin, tetracycline and chloramphenicol. Resistance to penicillin and ampicillin was mediated by beta-lactamase. In vivo evaluation of dermonecrosis in rabbits using L. laeta venom co-inoculated with isolate C. perfringens H28 produced an increase in the area of dermonecrotic lesions in the presence of penicillin and tetracycline, but not with gentamicin. Antibiotic therapy Loxosceles poisoning should be re-evaluated, considering the existence of multi-resistant strains of C. perfringens.
Asunto(s)
Antibacterianos/farmacología , Clostridium perfringens/aislamiento & purificación , Glándulas Exocrinas/microbiología , Hidrolasas Diéster Fosfóricas/efectos adversos , Picaduras de Arañas/microbiología , Venenos de Araña/efectos adversos , Arañas/microbiología , Diente/microbiología , Animales , Antivenenos/administración & dosificación , Clostridium perfringens/efectos de los fármacos , Clostridium perfringens/patogenicidad , Expresión Génica , Inyecciones Intradérmicas , Masculino , Necrosis/inducido químicamente , Resistencia a las Penicilinas/efectos de los fármacos , Resistencia a las Penicilinas/genética , Penicilinas/farmacología , Hidrolasas Diéster Fosfóricas/administración & dosificación , Hidrolasas Diéster Fosfóricas/análisis , Conejos , Piel/efectos de los fármacos , Picaduras de Arañas/tratamiento farmacológico , Venenos de Araña/administración & dosificación , Venenos de Araña/análisis , Tetraciclina/farmacología , Resistencia a la Tetraciclina/efectos de los fármacos , Resistencia a la Tetraciclina/genética , beta-Lactamasas/metabolismoRESUMEN
The incidence sexually transmitted diseases (STD) is a global public health problem, highly complicated by infections produced by the human immunodeficiency virus. Parasitic etiological agents of STD in Chile are limited to trichomonas vaginalis, sarcoptes scabiei and phthirus pubis. Only T. vaginalis has a trophozoite stage which can be diagnosed with a high degree of success in the laboratory. The present study reports on four culture methods which facilitate the primary isolation of this protozoan from clinical samples. The best results for primary isolation of T. vaginalis were obtained using modified diamond media. It was demonstrated that Kupferberg-Agar medium was the best for growth of T. vaginalis without re-inoculation. The optimal pH for the growth of T. vaginalis in the cultures was 6.5, and 10 percent horse serum gave the best yields in development and viability of T. vaginalis over time.
La incidencia de las enfermedades de transmisión sexual (ETS) se mantiene como problema de salud pública a nivel mundial, agravado por las infecciones por los virus de la inmunodeficiencia humana. Los agentes etiológicos parasitarios de ETS que existen en Chile se limitan a Trichomonas vaginalis, Sarcoptes scabiei y Phthirus pubis. T. vaginalis sólo posee estadio de trofozoito por lo que el diagnóstico de laboratorio es de alta exigencia. En este trabajo se evaluaron 4 medios de cultivo para facilitar el aislamiento primario de este protozoo a partir de muestras clínicas. Con el medio Diamond Modificado se obtuvo los mejores resultados para el aislamiento primario de T. vaginalis. Se comprobó que el medio Kupferberg-Agar fue el más adecuado para el crecimiento sin repique de T. vaginalis. Se determinó que el pH del medio de cultivo para el crecimiento óptimo de T. vaginalis, fue dr 6,5, y suero quino al 10 por ciento fue la concentración de mejor rendimiento para desarrollo y viabilidad en el tiempo de T. vaginalis.
Asunto(s)
Humanos , Masculino , Femenino , Medios de Cultivo , Trichomonas vaginalis/crecimiento & desarrollo , Trichomonas vaginalis/patogenicidad , Naranja de Acridina , Chile , Incidencia , Prevalencia , Enfermedades de Transmisión SexualRESUMEN
Diterpenoids with trichomonicidal activity were isolated from the aerial parts of Azorella yareta Hauman. One was 13beta-hydroxyazorellane, together with the known constituents mulinolic acid, mulin-11,13-dien-20-oic acid, azorellanol and 13alpha-hydroxyazorellane. Their structures were determined by spectroscopic and chemical methods.
Asunto(s)
Antiprotozoarios/aislamiento & purificación , Diterpenos/aislamiento & purificación , Magnoliopsida/química , Trichomonas vaginalis/efectos de los fármacos , Animales , Antiprotozoarios/química , Antiprotozoarios/farmacología , Diterpenos/química , Diterpenos/farmacologíaRESUMEN
The effect of El Niño/ENSO on terrestrial atmosphere appears to be extremely clear. However there are outstanding evidences showing its effect on humans and their activities. In fact, prevalence of some parasitic infections have increased during El Niño phenomenon. The reasons for that are the migrations of sylvatic mammals, fishes and birds as well as by environmental contamination. In this report, we show evidence respect of new cases of human infection by Diphyllobothrium pacificum clearly associated with a cyclic manifestation of El Niño in the Chilean Pacific coast during 1975-2000.
Asunto(s)
Difilobotriosis/etiología , Productos Pesqueros/parasitología , Conceptos Meteorológicos , Adolescente , Adulto , Animales , Niño , Preescolar , Chile , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
We report a 26 years old asymptomatic female that expelled spontaneously a 39 proglottid strobila. The taxonomic study of proglottids and eggs found in the stool examination concluded that the patient was infected by Diphyllobothrium pacificum. This infection was probably acquired by the ingestion of raw fish (Sciaena deliciosa) with lemon in a traditional plate called "cebiche". She was treated with a single dose of praziquantel in a dose of 10 mg/kg body weight. After 24 h of treatment there were no scolices on feces. The patient did not have anemia. All eight family members studied, did not have the infection. A follow up stool examination three months later remained negative.
Asunto(s)
Antiplatelmínticos/uso terapéutico , Difilobotriosis/diagnóstico , Productos Pesqueros/parasitología , Praziquantel/uso terapéutico , Adulto , Chile , Difilobotriosis/tratamiento farmacológico , Difilobotriosis/microbiología , Femenino , HumanosRESUMEN
The trypanocidad activity against amastigote forms of SPA-14, Tulahuen and G strains and CL Brener clone of Trypanosoma cruzi of diterpenoids isolated from Azorella compacta, Phil. (Llareta), a plant with ethnomedicinal prestige from prespanish age, was investigated. Amastigocidal activity was shown in azorellanol (2), diterpene isolated by first time, with an inhibitory concentration 50 (IC50) that varied between 60 M (CL Brener clone) and 84 M (SPA-14 strain), and in mulin -11,13 -dien-20-oico acid (5) with IC50 between 41 microM (G strain) and 87 mM (CL Brener clone). The cytotoxicity levels of both compounds against Hela and Vero cells and macrophages J144 are lower than nifurtimox and similar to gentian violet.
Asunto(s)
Extractos Vegetales/farmacología , Plantas Medicinales , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Chlorocebus aethiops , Células HeLa/efectos de los fármacos , Humanos , Macrófagos/efectos de los fármacos , Extractos Vegetales/química , Trypanosoma cruzi/citología , Células Vero/efectos de los fármacosRESUMEN
Among collections of Triatoma spinolai from various sites in northern Chile, adults from coastal populations are invariably wingless, whereas inland populations show balanced alary polymorphism between wingless females and males that are either winged or wingless. Laboratory crosses showed that male offspring from normal-winged parents were always winged (88% long-winged) and those from long-winged male parents were all long-winged. The male offspring from wingless males always included winged males: 11/33 = 33%, of which 8/11 = 73% were long-winged. An X-linked mutation is proposed to inhibit wing development. Field studies of population demography indicate that male alary polymorphism is advantageous in the desert environment of northern Chile.
Asunto(s)
Variación Genética , Triatoma/anatomía & histología , Alas de Animales/crecimiento & desarrollo , Animales , Chile , Femenino , Técnicas In Vitro , Masculino , Mutación , Dinámica Poblacional , Factores Sexuales , Triatoma/genéticaRESUMEN
In order to contribute to a better knowledge of the pediculosis capitis and scabies during March-December 1995, 1122 primary schoolchildren under 14 years of age in the city-port of Antofagasta in northern Chile (20 degrees South lat.), were examined. A total of 285 (25.4%) were found to be infested with Pediculus humanus capitis and only 20 (1.8%) with Sarcoptes scabiei. In general the rates of infestation to both ectoparasitic diseases were higher in groups of younger schoolchildren, also higher in women than in men and in those groups with high indexes of crowding and ignorance of the transmission mechanism of pediculosis capitis and scabies.
Asunto(s)
Infestaciones por Piojos/epidemiología , Escabiosis/epidemiología , Dermatosis del Cuero Cabelludo/epidemiología , Adolescente , Niño , Chile/epidemiología , Femenino , Humanos , Masculino , PrevalenciaRESUMEN
In order to assess the impact of a control program against Triatoma infestans launched in 1988, based on insecticide spraying of dwellings, a serological survey for chagasic infection was carried out during 1995 in three localities from San Pedro de Atacama County (22 degrees 55' South lat., 68 degrees 12' West long.), II Region of Antofagasta in northern Chile. Blood samples from 531 children and adolescents and 65 dogs were subjected to ELISA test and indirect immunofluorescent test for Chagas' disease respectively. Tests resulted positive in 12 (2.3%) persons, all above 5 years old, in contrast with the 16.8% serological positivity observed in 1985. Three (4.6%) dogs (two 0-12 months old) resulted positive. These results indicate that dwelling sprayings with long-term activity insecticides against T. infestans is a good tool to prevent new human infections with T. cruzi. However, active vector transmission among domestic animals (canines) could be recently acquired.
Asunto(s)
Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/veterinaria , Enfermedades de los Perros/epidemiología , Adolescente , Animales , Enfermedad de Chagas/sangre , Niño , Preescolar , Chile , Enfermedades de los Perros/sangre , Perros , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Prevalencia , Estudios SeroepidemiológicosRESUMEN
In the present work we have investigated the serum antibody spectrum to parasite antigens involved in human T. cruzi infection. Analysis was performed by conventional serology (IHA, IFAT and ELISA), complement-mediated lysis, anti-gal antibody assay and reactivity against recombinant and synthetic peptides and metacyclic antigens by immunowestern-blotting. All the sera showed a significant reactivity in IHA, IFAT and ELISA. We found that 84.2% of the sera showed lytic activity and thirty serum samples (78.9%) which showed a lytic activity higher than 50%, also showed anti-gal antibodies at serum dilutions higher than 1:1,600. Ninety-four percent of sera reacted with one or more of the recombinant DNA clones and 97.3% reacted with one or more of the synthetic peptides. A pool of serum samples with a lytic activity higher than 75% were able to produce 60% to 78% inhibition of cell invasion. Thirty-six of the serum samples (94.7%) were able to react by immunowestern blotting with a T. cruzi metacyclic antigen with molecular size of 70 kDa. The results obtained give preliminary information about the humoral immune response and the possible role of antibodies in protection against T. cruzi infection of chronic patients from the highlands of Chile.
Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Antígenos de Protozoos/inmunología , Enfermedad de Chagas/inmunología , Trypanosoma cruzi/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Formación de Anticuerpos , Enfermedad de Chagas/sangre , Chile , Ensayo de Inmunoadsorción Enzimática , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Pruebas de Hemaglutinación , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Twenty-one Trypanosoma cruzi stocks isolated from Triatoma infestans and humans of the Chilean Andean highlands were studied at the genotypic level by schizodeme and molecular karyotype analyses, which allowed a clear distinction of the parasites from those hosts. A phenotypical characterization was performed by proteolytic activity after electrophoretic fractionation without discrimination among the stocks. Metacyclic trypomastigotes obtained in vitro proved to be infective to Swiss mice and the study of immune response and biological behavior was assessed. Of a total of 21 T. cruzi stocks, only 11 proved to be infective in mice due to difficulties in obtaining metacyclic trypomastigotes with the parasite populations isolated from humans. Western blot analysis revealed a complex immune response even in the first days postinfection with each T. cruzi strain studied. Antigenic recognition by each immune serum is characteristic, although several major and common antigens were detected. Lytic antibodies were studied by the in vitro complement-mediated lytic assay using purified metacyclic trypomastigotes as target cells. All the T. cruzi isolates tested induced lytic antibodies in this experimental model. Parasitemias were moderate and characteristic for each T. cruzi strain. Results are compared with metacyclic forms of the infective and pathogenic Tulahuen strain.
Asunto(s)
Enfermedad de Chagas/parasitología , Triatoma/parasitología , Trypanosoma cruzi/aislamiento & purificación , Animales , Anticuerpos Antiprotozoarios/sangre , Western Blotting , Enfermedad de Chagas/sangre , Enfermedad de Chagas/inmunología , Chile , ADN Protozoario/análisis , ADN Protozoario/genética , Geografía , Humanos , Cariotipificación , Ratones , Proteínas Protozoarias/análisis , Proteínas Protozoarias/metabolismo , Trypanosoma cruzi/genética , Trypanosoma cruzi/fisiologíaRESUMEN
Antibodies levels against Gal alpha 1,3 Gal epitopes were studied in 407 human sera (92 chagasic and 315 non-chagasic), by means of hemagglutination with rabbit erytrocytes reactivity of serum having high titres of anti-Gal antibodies in presence of Escherichia coli and Serratia marcescens antigen was studied by immunoelectrotransference. Finally, using a purified anti-Gal antibody, Gal alpha 1,3 Gal epitopes were identified in metacyclic forms from 12 high Andean Chilean strains of Trypanosoma cruzi. Among the chagasic sera, it was demonstrated that in 63 (68.5%) were detected antibodies anti-Gal at the same or higher titer than 1:1,600; while i the non chagasic sera only 49 (15.6%) showed and anti-Gal response at similar titers. Immunoelectrotransference showed that the sera of people infected with T. cruzi recognize antibodies present in E. coli and S. marcescens, which reinforces the idea that at least in part, these bacterias would be capable of stimulating these responses. The autoradiographic analysis using purified anti-Gal antibodies, showed differences in the Gal alpha 1,3 Gal epitopes expressed in the different strains of T. cruzi. These results suggest that anti-Gal antibodies could have a real significance on the natural immunity mechanisms and protection of human infection with T. cruzi.
Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Enfermedad de Chagas/inmunología , Disacáridos/inmunología , Enterobacteriaceae/inmunología , Inmunoglobulina G/sangre , Trypanosoma cruzi/inmunología , Animales , Especificidad de Anticuerpos , Epítopos/inmunología , Humanos , Leishmaniasis/inmunologíaRESUMEN
Antofagasta, the big city-port in North Chile is a triatomines free locality. Chagas infection was serologically diagnosed in 44 out of 2063 (2.1%) pregnant women from Antofagasta, studied by means of an indirect immunoflourescence test (IIFT), during 1991-1993. Out of the 44 seropositive mothers, 31 and 10 were born in the II (moderate endemic area) and IV Región (hiperendemic area), respectively. The usefulness of a screening programme for congenital Chagas' disease at primary health care in Chile is discussed.
Asunto(s)
Enfermedad de Chagas/epidemiología , Complicaciones Parasitarias del Embarazo/epidemiología , Adolescente , Adulto , Chile/epidemiología , Femenino , Humanos , Recién Nacido , Embarazo , Prevalencia , Estudios SeroepidemiológicosRESUMEN
In order to contribute to a better knowledge of the chronic chagasic myocardiopathy, a post-mortem serological and anatomopathological study of Chagas' disease was carried out in 40 corpses. Between november 1987 and august 1988, autopsies were performed at the Pathological Anatomy Service of Antofagasta Regional Hospital and the Legal Medicine Section of the Ministry of Justice in Antofagasta. Positive postmortem chagasic serology, by using an indirect immunofluorescence test in pericardial fluid, was confirmed in three cases, among which the study of the histopathology of the cardiac muscle showed "Trypanosoma cruzi type" elements of the damage. The macroscopic morphological study did not show relevant findings. Results reveal the need to implement anatomopathological study systems for routines which contribute to evaluate the chagasic etiology as a cause of death among population of the endemic Chilean area.
Asunto(s)
Cardiomiopatía Chagásica/sangre , Cardiomiopatía Chagásica/patología , Adulto , Anciano , Cadáver , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miocardio/patología , Pruebas SerológicasRESUMEN
In January 1989--December 1991 period we verified 35 cases of symptomatic intestinal amebiasis in Antofagasta, the main city of the North of Chile. Out of the total number of studied patients 23 were adults (77.1% males and 22.9% females) and all of them were permanent residents of Antofagasta. E.histolytica was frequently detected in association with other parasites and/or commensals, and observed alone in only seven cases. The clinical and epidemiological aspects of these 35 cases are discussed.
Asunto(s)
Disentería Amebiana/epidemiología , Adolescente , Adulto , Niño , Preescolar , Chile/epidemiología , Disentería Amebiana/diagnóstico , Disentería Amebiana/tratamiento farmacológico , Femenino , Humanos , Lactante , Masculino , Metronidazol/uso terapéutico , Persona de Mediana Edad , Tinidazol/uso terapéuticoRESUMEN
Se presenta un estudio enteroparasitológico practicado a 212 niños en edad preescolar y escolar de dos comunidades altiplánicas (San Pedro de Atacama y Toconao) ubicadas entre los 22o55' y 23o11' lat. sur y 68o12' y 68o long. oeste, en la II región, Antofagasta. El 94,8% de los encuestados presentó infección por protozoos o helmintos intestinales. Entre los protozoos parásitos destacan Giardia Lamblia (35,4%) y Entamoeba Histolytica (3,8%), mientras que entre los comensales (índice de fecalismo humano), lo fueron Entamoeba Coli (79,7%); Endolimax Nana (56,1%) y Iodamoeba Bustchlii (31,1%). Los enterohelmintos más frecuentemente encontrados fueron: Enterobius vermicularis (46,7%) e Hymenolepis Nana (22,6%) Los antecedentes epidemiológicos en ambas comunidades revelan: déficit en la educación sanitaria, alto grado de hacinamiento por vivienda, consumo de agua no potable, eliminación de basuras y excretas a campo abierto. Estos factores son los que condicionan la mantención y propagación de las infecciones por protozoos y helmintos intestinales, particularmente en las comunidades altiplánicas rurales indoamericanas