Trichinella spiralis: monoclonal antibody against the muscular larvae for the detection of circulating and fecal antigens in experimentally infected rats.

In this work we search for antigens of Trichinella spiralis in sera and stool of rats experimentally infected. The kinetic of antibodies to excretory and secretory (ES) antigens of muscle larvae (ML) was also determined. Wistar rats were infected with 15 ML per gram of body weight and blood samples were collected weekly for 10 weeks. Antibodies were studied using an indirect ELISA. For detection of circulating antigens and coproantigens, a sandwich ELISA was developed with the use of polyclonal rabbit antibodies obtained against the total extract of ML and an IgM monoclonal antibody (Mab) against ES antigens of ML. No reactivity was observed between Mab and the total worm antigens of Angiostrongylus cantonensis, Ascaris suum, Echinococcus granulosus, Fasciola hepatica, Strongyloides stercoralis, Taenia solium, Toxocara canis and Trichuris trichiura. The IgM Mab recognized antigens of 45, 49, and 55 kDa in ES antigens and was unable to bind ES antigens deglycosylated with trifluoromethanesulphonic acid (TFMS) indicating that a glycan structure is present in the epitope recognized by this Mab. The sensitivity of sandwich ELISA was 1 ng/mL. Circulating antigens were detected in all infected rats between 3 and 8 weeks post infection and coproantigens were found during the first two days post infection. Antibodies were detected since the third week post infection through the end of experiment. These results suggested that antigen detection by our sandwich ELISA could be a useful complementary laboratory test for antibody detection.

Nanostructured Systems in Advanced Drug Targeting for the Cancer Treatment: Recent Patents.

BACKGROUND: Cancer is one of the leading causes of death in the world and it is necessary to develop new strategies for its treatment because most therapies have limited access to many types of tumors, as well as low therapeutic efficacy and high toxicity. OBJECTIVE: The present research aims to identify recent patents of drug delivery nanostructured systems that may have application in improving cancer treatment. METHODS: Recent patents regarding the drug delivery nanostructured systems for cancer treatment were obtained from the patent databases of the six main patent offices of the world: United States Patent and Trademark Office, European Patent Office, World Intellectual Property Organization, Japan Patent Office, State Intellectual Property Office of China and Korean Intellectual Property Office. RESULTS: A total of 1710 patent documents from 1998 to 2017 including "drug delivery nanostructured systems for cancer treatment" were retrieved. The top five countries in patent share were USA, China, South Korea, Canada and Germany. The universities and enterprises of USA had the highest amount of patents followed by institutions from China. CONCLUSION: There is a strong tendency for the development of new nanostructured systems for the release of drugs; particularly, in recent years, the development of nanoparticles has focused on nanodiscs, gold nanoparticles and immunoliposomes.

Comparative Diagnosis of Serum IgG1 and Coproantigen ELISA for Fasciolosis Detection of Goats in Mexico.

The objective of present study was to determine the prevalence of natural caprine fasciolosis in the Mixteca region of Mexico using coproantigen and serum IgG1 ELISA tests for comparative purposes. A total of 1070 serum and faecal samples were analyzed for IgG1 antibodies and coproantigens, using ELISA with E/S products as antigen and a monoclonal antibody-based sandwich ELISA. Prevalence of 73.46% was found using the serological ELISA and a percentage of 77.20 was found for coproantigen ELISA. The diagnostic sensitivity and specificity for serum ELISA were 86.7% and 96.4%, and for the coproantigen ELISA they were 93.1% and 97.8%, respectively. The seropositive samples were further categorized as low, medium, or high positivity. Results show a great proportion of low and medium positive goats when the serum ELISA test was used. Correlation coefficients between coproantigens and seropositivity were statistically significant (P < 0.01) for low seropositivity (r = 0.93) and medium seropositivity (r = 0.84). The accuracy of faecal antigen ELISA was higher compared to indirect ELISA serological test. Two ELISAs were shown to be useful for demonstrating the current status of F. hepatica infection in the endemic areas and can be employed in studies on epidemiology as well as anthelmintics treatment for preventing economic loss and the risk of transmission to humans.

Fascioliasis and intestinal parasitoses affecting schoolchildren in Atlixco, Puebla State, Mexico: epidemiology and treatment with nitazoxanide.

BACKGROUND: The Atlixco municipality, Puebla State, at a mean altitude of 1840 m, was selected for a study of Fasciola hepatica infection in schoolchildren in Mexico. This area presents permanent water collections continuously receiving thaw water from Popocatepetl volcano (5426 m altitude) through the community supply channels, conforming an epidemiological scenario similar to those known in hyperendemic areas of Andean countries. METHODOLOGY AND FINDINGS: A total of 865 6-14 year-old schoolchildren were analyzed with FasciDIG coproantigen test and Lumbreras rapid sedimentation technique, and quantitatively assessed with Kato-Katz. Fascioliasis prevalences ranged 2.94-13.33% according to localities (mean 5.78%). Intensities were however low (24-384 epg). The association between fascioliasis and the habit of eating raw vegetables was identified, including watercress and radish with pronouncedly higher relative risk than lettuce, corncob, spinach, alfalfa juice, and broccoli. Many F. hepatica-infected children were coinfected by other parasites. Entamoeba histolytica/dispar, Giardia intestinalis, Blastocystis hominis, Hymenolepis nana and Ascaris lumbricoides infection resulted in risk factors for F. hepatica infection. Nitazoxanide efficacy against fascioliasis was 94.0% and 100% after first and second treatment courses, respectively. The few children, for whom a second treatment course was needed, were concomitantly infected by moderate ascariasis burdens. Its efficacy was also very high in the treatment of E. histolytica/E. dispar, G. intestinalis, B. hominis, H. nana, A. lumbricoides, Trichuris trichiura, and Enterobius vermicularis. A second treatment course was needed for all children affected by ancylostomatids. CONCLUSIONS: Fascioliasis prevalences indicate this area to be mesoendemic, with isolated hyperendemic foci. This is the first time that a human fascioliasis endemic area is described in North America. Nitazoxanide appears as an appropriate alternative to triclabendazole, the present drug of choice for chronic fascioliasis. Its wide spectrum efficacy against intestinal protozooses and helminthiasis, usually coinfecting liver fluke infected subjects in human endemic areas, represents an important added value.

Regulación por helmintos de las respuestas inmunitarias del hospedero / Helminth regulation of host immune responses

Introducción: durante las últimas dos décadas se ha producido una rápida acumulación de conocimientos sobre la inmunología de las helmintosis. La información ahora disponible permite un mejor entendimiento de los mecanismos defensivos del hombre contra la infección por helmintos. Otra área del saber sobre la inmunología de las helmintosis, la relacionada con la regulación de las respuestas inmunitarias del hospedero ejercida por el parásito, con sus muy disímiles implicaciones clínicas y epidemiológicas, también se ha beneficiado de la expansión cognoscitiva de los últimos años. Objetivos: revisar lo publicado sobre las evidencias, mecanismos y consecuencias de la regulación de las respuestas inmunitarias del hospedero ejercida por los helmintos. Métodos: con el auxilio de diferentes buscadores electrónicos, se realiza una revisión de los artículos sobre helmintos, helmintosis y regulación de las respuestas inmunitarias del hospedero publicados durante el período 1995-2015. Algunas monografías y artículos originales fechados con anterioridad al intervalo mencionado también fueron consultados. Resultados: se expone y analiza, y hasta donde es posible se sistematiza, la información colectada sobre los temas seleccionados. Conclusiones: datos epidemiológicos, clínicos y experimentales evidencian que los helmintos logran modular las respuestas inmunitarias de sus respectivos hospederos y con ello sobrevivir en aquellos. Adicionalmente, la modulación de las respuestas inmunitarias del hospedero tiene importantes consecuencias clínicas y epidemiológicas que, en aras de una práctica médica de mejor calidad, deben ser conocidas por los profesionales relacionados con el diagnóstico, tratamiento y control de estas parasitosis(AU)

Introduction: the last two decades have witnessed a swift accumulation of knowledge about the immunology of helminthiases. The information now available allows to better understand human defense mechanisms against helminth infection. Another area of knowledge about the immunology of helminthiases which has also benefited from such recent expansion of knowledge is the regulation of host immune responses by the parasite, with its great variety of clinical and epidemiological implications. Objectives: review publications about the evidence, mechanisms and consequences of the regulation of host immune responses by helminths. Methods: using various search engines, a review was conducted of papers about helminths, helminthiasis and regulation of host immune responses published from 1995 to 2015. Several monographs and original papers dated before that period were also consulted. Results: the information gathered about the topics selected is presented, analyzed and whenever possible systematized. Conclusions: epidemiological, clinical and experimental data show that helminths can modulate the immune responses of their hosts and thus survive within them. Additionally, modulation of host immune responses has important clinical and epidemiological consequences which should be known by professionals related to the diagnosis, treatment and control of these parasitic diseases in order to improve the quality of medical practice(AU)

[Effect of 4B3 monoclonal antibody on the experimental Cryptococcus neoformans infection]. / Efecto del anticuerpo monoclonal 4B3 en la infección experimental por Cryptococcus neoformans.

INTRODUCTION: frequent relapses and high lethality of criptococcosis has encouraged the search for new therapeutic strategies. OBJECTIVES: to evaluate the effect of the monoclonal antibody 4B3 on the cryptococcal infection in Balb/c mice. METHODS: the kinetics in serum concentration of the studied monoclonal antibody was determined for intraperitoneal administration (500 microg) by quantitative sandwich ELISA. In order to assess its protective capability, were administered 500 microg of 4B3 and innoculated 2 x 10(22) cells/mL of Cryptococcus neoformans. The survival of mice was recorded and the yeast dissemination to the main target organs was evaluated. Macrophages P338.D1 cell lines were used to measure the effect of the monoclonal antibody 4B3 on the phagocytosis and lysis of the microorganism. RESULTS: the used dose helped to keep high values (38 microg/m) of 4B3 in serum for at least 46 days. It was found that the monoclonal antibody does not give protection, which makes the microorganism dissemination possible, along with the reduction in the survival of mice. Finally, the phagocytosis test showed that 4B3 increased the phagocytic activity of macrophages without any fungicidal effect. CONCLUSIONS: the monoclonal antibody 4B3 stimulates C. neoformans phagocytosis by macrophages without fungicidal effect, thus favoring yeast dissemination and decreasing the survival of mice due to cryptococcal infection

Angiostrongylus cantonensis: un parásito emergente en Ecuador / Angiostrongylus cantonensis: an emerging parasite in Ecuador

Introducción: en 2008 se notificó por primera vez la presencia de Angiostrongylus cantonensis en Ecuador, así como los primeros casos de una enfermedad emergente causada por sus larvas, la meningitis eosinofilica. Métodos: se realizó una revisión de la literatura básica y actualizada sobre aspectos generales de Angiostrongylus cantonensis en el mundo y particulares en Ecuador, que incluyó los hallazgos parasitológicos, clínicos y malacológicos relacionados con la enfermedad. Resultados: se informan los hallazgos iniciales acerca de la aparición del parásito en Ecuador, así como la amplia distribución geográfica de sus hospederos intermediarios en el territorio nacional. Además, se notifican los brotes de meningitis eosinofilica por Angiostrongylus cantonensis y un caso de angiostrongyliosis ocular, informados oficialmente por el Ministerio de Salud Pública. Conclusiones: Angiostrongylus cantonensis es un parásito emergente en Ecuador, cuyo diagnóstico en la actualidad es clínico y epidemiológico, de ahí la importancia de contar con métodos de laboratorio que lo oriente. Por otra parte, es importante que se promuevan campañas de promoción y prevención de salud que contribuyan a romper la cadena de transmisión de la enfermedad.

Introduction: the presence of Angiostrongylus cantonensis and the first cases of eosinophilic meningitis, an emerging disease caused by its larvae, were first reported in Ecuador in the year 2008. Methods: a review was conducted of the basic and current bibliography on general aspects of Angiostrongylus cantonensis both worldwide and in Ecuador, including parasitological, clinical and malacological findings. Results: initial findings are reported about the emergence of the parasite in Ecuador, as well as the broad geographic distribution of its intermediate hosts in the national territory. Information is also provided about outbreaks of eosinophilic meningitis due to Angiostrongylus cantonensis and a case of ocular angiostrongylosis, based on official reports by the Ministry of Public Health. Conclusions: Angiostrongylus cantonensis is an emerging parasite in Ecuador whose diagnosis is currently based on clinical and epidemiological findings. Hence the importance of developing relevant laboratory methods. On the other hand, it is important to foster health promotion and prevention campaigns aimed at stopping the transmission of the disease.

Evaluación de tres dietas alimentarias para el período larval de Aedes aegypti en condiciones de laboratorio / Assessment of three feeding diets for the Aedes aegypti larval stage under lab conditions

Introducción: la alimentación en el período larval del mosquito es sumamente importante, debido a que en esta etapa almacenan los nutrientes básicos para el desarrollo de la pupa y el adulto. Objetivo: evaluar la calidad de tres dietas como fuente nutritiva y su influencia en el desarrollo de las fases preadultas de Aedes aegypti. Métodos: se evaluaron tres dietas en el insectario del Instituto Pedro Kourí, concentrado CENPALAB, elaborado en el Centro para la Producción de Animales de Laboratorio (CENPALAB), levadura torula, subproducto de la caña de azúcar (ambas de producción nacional) y harina de pescado, producto de importación. Previamente, se determinó la calidad higiénica-microbiológica y química nutricional de las dietas. Se evaluaron variables biológicas como el número de pupas diarias por alimentos y la duración del ciclo larval; se determinó la cantidad de proteínas presentes en las larvas alimentadas con cada dieta, mediante el método de Lowry. Resultados: la calidad higiénica-microbiológica, así como la caracterización química nutricional de los 3 alimentos evaluados, aportaron resultados satisfactorios para el desarrollo de la investigación. Los valores mayores en la concentración de proteínas y en la actividad biológica en la fase larval del mosquito se obtuvieron con la harina de pescado. No se encontraron diferencias significativas en la concentración de proteínas entre las dietas en los primeros días del período larval, A partir del quinto hasta el séptimo día de vida, la harina de pescado fue superior al concentrado CENPALAB. La emergencia de pupas comenzó al sexto día para todas las dietas, obteniéndose el pico más alto al séptimo día con diferencias entre estas. El ciclo larval duró de 7 a 8 días. Conclusiones: se sugiere la utilización de las dietas de producción nacional en situaciones que lo requieran por carencia de la dieta importada, para no detener el desarrollo de las investigaciones

Introduction: feeding mosquitoes during the larval stage is an important process, since it is the stage in which basic nutrients are stored for the subsequent development of pupas and adults. Objective: to evaluate both the quality of three diets as nutritional source and the influence these diets have on the development of the Aedes aegypti in its pre-adult stage. Methods: three different diets were evaluated at the Insectarium of the Pedro Kourí Tropical Medicine Institute in Havana, Cuba. The diets evaluated were: CENPALAB Food Concentrate, elaborated at the Center for Laboratory Animal Production (CENPALAB, Spanish acronym) and torula yeast, a sugar cane byproduct (both of them from domestic production) as well as fish flour, an imported product

[Monoclonal antibody mimicking the structure of an immunoprotective epitope against Fasciola hepatica]. / Anticuerpo monoclonal que mimetiza la estructura de un epítope inmunoprotector contra Fasciola hepatica.

The ES-78 monoclonal antibodiy recognizes excretory-secretory antigens of Fasciola hepatica. This monoclonal antibody is used for diagnosis of humans and cattle fasciolosis. The production of 4 anti-idiotype monoclonal antibodies (3G5, 5G1, 3H4 and 1H6) inhibiting the antigen-monoclonal antibody ES 78 reaction was reported. This antibody recognizes excretion-secretion antigens of Fasciola hepatica and it is used for the diagnosis in faeces of fascioliasis in the bovine cattle and in humans. When the 3G5 was used in rabbits as an immunogen there was a response of antibodies against the excretion-secretion antigen of Fasciola hepatica without a previous contact wih it. The utilization of this anti-idiotype monoclonal antibody as an immunogen mimmicking a protective epitope against fascioliasis together with appropriate adjuvants may be a new way of reducing the parasitic burden in experimental models of fascioliasis.

[Recognition of intact cells from Cryptococcus neoformans by the anti-glucuronoxylomannan 4B3 monoclonal antibody]. / Reconocimiento de células intactas de Cryptococcus neoformans por el AcM 4B3 antiglucuronoxilomanano.

The capacity of the 4B3 monoclonal antibody, previously obtained by immunization of BALB/c mice with the capsular polysaccharide of Cryptococcus neoformans was studied to recognize this structure as part of the intact cell of this yeast. With this aim, 4B3 was evaluated by cellular ELISA and indirect immunofluorescence, using as an antigen a cell suspension of the 028 LMIPK C. neoformans strain. Serum from the mouse used in the fusion for obtaining 4B3 monoclonal antibody was used as a positive control, whereas an anti-dengue monoclonal antibody was used as a negative control. Both methods demonstrated that the above mentioned monoclonal antibody is capable of recognizing the native antigen, which will allow its future evaluation for diagnostic and therapeutic purposes.

Efecto del anticuerpo monoclonal 4B3 en la infección experimental por Cryptococcus neoformans / Effect of 4B3 monoclonal antibody on the experimental Cryptococcus neoformans infection

Introducción: las frecuencias de recaídas y elevada letalidad de la criptococosis se mantienen altas, lo cual incentiva la búsqueda de nuevas estrategias terapéuticas. Objetivos: evaluar el efecto del anticuerpo monoclonal 4B3 sobre la infección criptocócica en ratones BALB/c. Métodos: se determinó la cinética de la concentración sérica del anticuerpo monoclonal para su administración intraperitoneal (500 µg), que fue medida por ELISA cuantitativo de doble anticuerpo. La capacidad protectora se observó mediante el registro de supervivencia de ratones BALB/c administrados con 500 µg de anticuerpo monoclonal 4B3 e inoculados con 2 x 10(2,2) células/mL de Cryptococcus neoformans, así como por evaluación de la diseminación de la levadura a los principales órganos diana. Se identificó el efecto del anticuerpo monoclonal 4B3 sobre la fagocitosis y lisis del microorganismo por células de la línea de macrófagos P338.D1. Resultados: la dosis empleada fue suficiente para mantener valores séricos elevados del 4B3 (38 µg/mL) durante al menos 46 d. Se determinó que el 4B3 no confiere protección, lo cual potencia la diseminación del microorganismo y disminuye el tiempo de vida de los animales. El ensayo de fagocitosis mostró que el anticuerpo evaluado incrementa la actividad fagocítica de los macrófagos sin lograr un efecto fungicida. Conclusiones: el anticuerpo monoclonal 4B3 estimula la fagocitosis de C. neoformans por macrófagos, pero sin efecto fungicida. Con ello favorece la diseminación de la levadura y disminuye el tiempo de vida de los ratones a la infección.

Introduction: frequent relapses and high lethality of criptococcosis has encouraged the search for new therapeutic strategies. Objectives: to evaluate the effect of the monoclonal antibody 4B3 on the cryptococcal infection in Balb/c mice. Methods: the kinetics in serum concentration of the studied monoclonal antibody was determined for intraperitoneal administration (500 µg) by quantitative sandwich ELISA. In order to assess its protective capability, were administered 500 µg of 4B3 and innoculated 2 x 10(2.2) cells/mL of Cryptococcus neoformans. The survival of mice was recorded and the yeast dissemination to the main target organs was evaluated. Macrophages P338.D1 cell lines were used to measure the effect of the monoclonal antibody 4B3 on the phagocytosis and lysis of the microorganism. Results: the used dose helped to keep high values (38 µg/m) of 4B3 in serum for at least 46 days. It was found that the monoclonal antibody does not give protection, which makes the microorganism dissemination possible, along with the reduction in the survival of mice. Finally, the phagocytosis test showed that 4B3 increased the phagocytic activity of macrophages without any fungicidal effect. Conclusions: the monoclonal antibody 4B3 stimulates C. neoformans phagocytosis by macrophages without fungicidal effect, thus favoring yeast dissemination and decreasing the survival of mice due to cryptococcal infection.

Conservación de heces humanas para la detección de antígenos de excreción-secreción de Fasciola hepatica / Preservation of human stools for the detection of Fasciola hepatica excretory secretory antigens

INTRODUCCIÓN: la fasciolosis en Cuba es una enfermedad endémica en el ganado y en los últimos años ha tenido un incremento en el número de casos reportados en humanos. OBJETIVOS: por causa de las dificultades para realizar el diagnóstico de esta enfermedad en zonas rurales o alejadas del laboratorio se ha hecho necesario buscar soluciones preservantes, que permitan conservar las muestras de heces hasta el momento de la determinación de antígeno por el método de FasciDIG®. MÉTODOS: se utilizaron diferentes soluciones preservantes (dicromato de potasio 2 por ciento, hibitane acuoso 0,5 por ciento, glutaral 2 por ciento, cloruro de benzalconio 1 por ciento, azida sódica 0,04 por ciento y agua destilada con tween 20 0,05 por ciento) a temperatura ambiente, 4 ºC y - 20 ºC. RESULTADOS: en las muestras preservadas a temperatura ambiente, las que no tenían preservo sufrieron un gran deterioro, mostraron valores superiores a las conservadas con agua tween 20 y con azida sódica. Esta última es un producto altamente tóxico, por ser un inhibidor de la cadena respiratoria y requeriría de un mayor cuidado en su utilización. CONCLUSIONES: se sugiere que la solución preservante de agua destilada con tween 20 0,05 por ciento a temperatura ambiente mostró los mejores resultados en el estudio.

INTRODUCTION: fascioliasis is an endemic disease in cattle in Cuba, but in the last few years, there has been an increase in the number of reported human cases. OBJECTIVES: the difficulties in diagnosing this disease in rural areas or in zones far away from the laboratory make it necessary to find adequate solutions that allow preserving the stool specimens until the antigen is detected by the FasciDIG® method. METHODS: several preserving solutions were used (2 percent potassium dichromate, 0,5 percent aqueous hibitane, 2 percent glutaral, 1 percent benzalkonium chloride, 0,04 percent sodic azide and 0,05 percent distilled water with 20 tween) at room temperature, 4 ºC and - 20 ºC. RESULTS: among the samples kept at room temperature, those with no preserve suffered a significant deterioration, and their values were higher than the ones of the samples conserved with distilled water with tween 20 and with sodium azide. The latter is a very toxic product and its use would require a greater care. CONCLUSIONS: 0,05 percent distilled water with 20 tween at room temperature was the preserving solution with the best results in this study.

Infección humana por Trichomonas vaginalis y su relación con otros agentes patógenos / Human infection from Trichomonas vaginalis and its relation to other pathogen agent

Trichomonas vaginalis es un protozooo flagelado causante de la trichomonosis urogenital en humanos. La asociación y coexistencia de T. vaginalis con otros agentes patógenos causantes de infecciones de transmisión sexual es bastante común. Se realizó una revisión de la literatura, incluyendo las últimas publicaciones sobre las principales manifestaciones clínicas de T. vaginalis y su relación con otros agentes de transmisión sexual

Trichomonas vaginalis is a flagellate protozoon causing urogenital trichomoniasis in humans. Association and co-existence of T. vaginalis with other pathogen agents causing of sexually transmitted infections is fairly common. A bibliographic review was carried out including the last publications on the main clinical manifestations from T. vaginalis, and its relation to other sexual transmission agents

Parasitismo intestinal en una cohorte de escolares en 2 municipios de Ciudad de La Habana / Intestinal parasitism found in a school children cohort from two municipalities in the City of Havana province

Introducción: en Cuba el parasitismo intestinal constituye aún un problema de salud aunque mucho menor que en otros países subdesarrollados. Objetivo: esclarecer su magnitud en un grupo de escolares de Ciudad de La Habana. MÉTODOS: se estudiaron 312 niños de los 2 sexos, en edades comprendidas de 8 a 15 años, pertenecientes a la población escolar de las áreas de salud Vedado y Punta Brava, en los años 2002 y 2004. A cada niño se le realizó análisis de las heces mediante las técnicas de examen directo y de Kato Katz. Resultados: la prevalencia correspondió a una tasa de 45,2 /100 habitantes en 2004 y 48,4/100 habitantes en 2002. Los protozoos prevalecieron en ambos estudios. Blastocystis hominis fue el parásito más frecuente diagnosticado, que presentó cifras mayores en 2004 con una tasa de prevalencia de 19,2/100 habitantes y 15,7/100 habitantes en 2002. Entamoeba histolytica/dispar tuvo una prevalencia mayor en 2004 (6/100 habitantes). Dentro de los helmintos, Trichuris trichiura y Ascaris lumbricoides tuvieron una prevalencia mayor en 2002 con cifras de 11,2/100 habitantes y 5,1/100 habitantes, respectivamente. El dolor abdominal fue el síntoma más referido con una mayor asociación en el niño parasitado (RR> 2; p< 0,001). La coincidencia de niños parasitados en ambos años fue de 20,8 por ciento, y de estos, 38,4 por ciento mostró un bajo percentil y se destaca 35,3 por ciento de niños que nunca tuvieron parásitos. Conclusiones: los resultados obtenidos demuestran que a pesar del avance alcanzado por el sistema de salud, el parasitismo intestinal continúa siendo un desafío.

Background: Intestinal parasitism is still a health problem in Cuba, although much less serious than in other underdeveloped countries. Objective: to determine the extent of this disease in a group of school children from the City of Havana. Methods: Three hundred and twelve children from both sexes aged 8-15 years, who belonged to the school population from Vedado and Punta Brava health areas, were studied in the years 2002 and 2004. Each child´s feces were analyzed by direct examination and Kato Katz techniques. RESULTS: the prevalence rate was 48.4/100 pop in 2002 and 45.2/100 pop in 2004. Protozoa prevailed in both studies. Blastocystis hominis was the most diagnosed parasite presenting higher figures in 2004, with a prevalence rate of 19.2 /100 pop, whereas the figure was 15.7/100 pop in 2002. Entamoeba histolytica/dispar was more prevalent in 2004 (6/100 pop). Among the helminths, Trichuris trichiura y Ascaris lumbricoides exhibited higher prevalence rates in 2002, with 11.2/100 pop and 5.1/100 pop respectively. Abdominal pain was the most referred symptom, mostly associated to the affected child (RR> 2; p< 0.001). The coincident percentage of children with parasites was 20.8 percent in both years; of these, 38.4 percent showed low percentile and 35.3 percent of children did never suffer from parasitism. Conclusions: the results revealed that despite the advances of the healthcare system in Cuba, the intestinal parasitism continues to be a real challenge.

Anticuerpo monoclonal que mimetiza la estructura de un epítope inmunoprotector contra Fasciola hepatica / Monoclonal antibody mimicking the structure of an immunoprotective epitope against Fasciola hepatica

Se reportó la producción de 4 anticuerpos monoclonales anti-idiotipos (3G5, 5G1, 3H4 y 1H6) que inhiben la reacción antígeno-anticuerpo monoclonal ES-78, el cual reconoce antígenos de excreción-secreción de Fasciola hepatica y se emplea para el diagnóstico en heces de la fasciolosis en el ganado bovino y en humanos. Cuando se utilizó en conejos el 3G5, como inmunógeno, se produjo una respuesta de anticuerpos contra antígeno de excreción-secreción de Fasciola hepatica sin un previo contacto con este. El empleo como inmunógeno de este anticuerpo monoclonal anti-idiotipo, que mimetiza un epítope protector contra la fasciolosis, junto a adyuvantes apropiados puede ser una manera novedosa de disminuir la carga parasitaria en modelos experimentales de fasciolosis

Reconocimiento de células intactas de Cryptococcus neoformans por el AcM 4B3 antiglucuronoxilomanano / Recognition of intact cells from Cryptococcus neoformans by the anti-glucuronoxylomannan 4B3 monoclonal antibody

Se estudió la capacidad del anticuerpo monoclonal 4B3, obtenido mediante inmunización de ratones BALB/c con el polisacárido capsular de Cryptococcus neoformans, para reconocer a dicha estructura como parte de la célula intacta de esta levadura. Con este propósito el anticuerpo 4B3 fue evaluado mediante ELISA celular e inmunofluorescencia indirecta empleando como antígeno una suspensión de células de la cepa 028 LMIPK de Cryptococcus neoformans. Se usó como control positivo suero del ratón empleado en la fusión para la obtención del anticuerpo monoclonal 4B3 y como control negativo un anticuerpo monoclonal anti-dengue. Ambos métodos demostraron que este anticuerpo monoclonal es capaz de reconocer al antígeno nativo, lo que permitirá su posterior evaluación con fines diagnósticos y terapéuticos

The capacity of the 4B3 monoclonal antibody, previously obtained by immunization of BALB/c mice with the capsular polysaccharide of Cryptococcus neoformans was studied to recognize this structure as part of the intact cell of this yeast. With this aim, 4B3 was evaluated by cellular ELISA and indirect immunofluorescence, using as an antigen a cell suspension of the 028 LMIPK C. neoformans strain. Serum from the mouse used in the fusion for obtaining 4B3 monoclonal antibody was used as a positive control, whereas an anti-dengue monoclonal antibody was used as a negative control. Both methods demonstrated that the above mentioned monoclonal antibody is capable of recognizing the native antigen, which will allow its future evaluation for diagnostic and therapeutic purposes.

Inmunización intranasal de ratones con la proteína SAG2 de Toxoplasma gondii asociada con la toxina colérica / Intranasal immunization of mice with Toxoplasma gondii SAG2 protein associated with cholera toxin

Se estudió la capacidad como inmunógeno de la proteína SAG2 nativa del taquizoíto de T. gondii administrada por vía intranasal asociada con toxina colérica en ratones. El grupo de animales inmunizados con la proteína SAG2 sin adyuvante, presentó una menor carga de quistes cerebrales después del reto por vía oral con quistes de la cepa 76K de T. gondii. Se demostró la presencia de anticuerpos específicos contra esta proteína tanto en el nivel serológico (IgG), como en saliva (IgA), en todos los animales que recibieron la SAG2 en el esquema de inmunización

Mecanismo de acción del anticuerpo monoclonal ES-78 contra la fasciolosis / Action mechanism of ES-78 monoclonal antibody against fasciolosis

Se reportó recientemente que el anticuerpo monoclonal ES-78 es capaz de conferir protección pasiva contra fasciolosis. Se realizó la identificación de uno de los mecanismos mediante el cual ejerce su acción protectora contra la enfermedad. Este anticuerpo monoclonal fue capaz de realizar citotoxicidad mediada por anticuerpo tanto sobre células Raji marcadas con el antígeno de excreción-secreción de Fasciola hepatica como sobre parásitos recién desenquistados. Este anticuerpo monoclonal no inhibió la actividad de cisteíno proteinasa utilizando azocaseína como sustrato.

It was recently reported that the ES-78 monoclonal antibody is capable of giving passive protection against fasciolosis. One of the mechanisms by which it exerts its protective action against the disease was identified. We also demonstrated in this report the capability of this monoclonal antibody to produce antibody dependent cell citotoxicity on Raji cells coated with excretory-secretory antigens, as well as on newly disencysted parasites.. No inhibition of proteinase activity was found in presence of this monoclonal antibody when azocasein substrate was used.