Trichomonas vaginalis: la versatilidad de un parásito tenaz

Trichomonosis is one of the most prevalent nonviral sexually transmitted infection (S.T.I.) worldwide, with an estimated 276 million cases per year according to WHO overview. Little attention is paid to this disease, although more than 50% of S.T.I. curable are caused by this protozoon. Clinically, Trichomonas vaginalis infection can produce a wide range of pathological manifestations, from asymptomatic presentation to severe inflammatory and invasive lesions in the genitourinary tract of both men and women. The possible role displayed by T. vaginalis as a viral vector might also explain its role as a risk factor in the development of cervical and prostate neoplasia. In addition, trichomonosis is strongly associated with transmission and acquisition of other bacterial and viral pathogens like HIV. T. vaginalis is a very complex organism and has developed diverse mechanisms for the colonization of the genitourinary tract probably due to its extensive genome. This parasite must survive in a hostile environment exposed to continue fluctuations. Surprisingly, T. vaginalis possesses one of the largest and most repetitive genomes, with a core set of 60,000 protein-coding genes. According to all these features, T. vaginalis could be considered an excellent model of parasite to be studied in order to better understand the dynamics and immune evasion mechanisms of such versatile parasite.La tricomonosis urogenital humana, causada por el parásito Trichomonas vaginalis, es una de las infecciones de transmisión sexual (I.T.S.) de mayor prevalencia en el mundo, con un total de 276 millones de casos cada año, según la OMS.Algunos autores la han calificado como una enfermedad desatendida u olvidada ligada a la pobreza, a pesar de que más del 50% de las I.T.S. curables se deben a este agente etiológico. La tricomonosis cursa con un rango amplio de manifestaciones clínicas, que van desde casos asintomáticos hasta cuadros más graves e invasivos de los conductos genitourinarios. Se ha relacionado la infección con el riesgo de adquisición y transmisión del VIH y de lesiones preneoplásicas de cérvix y próstata. Este protozoo parásito presenta una gran variabilidad intraespecífica en su comportamiento patogénico, probablemente por el tamaño y complejidad de su genoma, con más de 60.000 genes codificantes. Es capaz de sobrevivir y colonizar un nicho complejo sometido a constantes fluctuaciones, el aparato genitourinario, pasando desapercibido en muchos casos. El tamaño y complejidad de su genoma convierten a T. vaginalis en un parásito de gran interés científico para el estudio de los mecanismos de patogenia y evasión de la respuesta inmune

Enfermedad de Chagas: El desenlace de un conflicto entre el Parásito y el Sistema Inmunitario

Chagas´ disease was described more than one hundred years ago, but its pathogenesis remains controversial. For several decades it has been considered as an autoimmune disease. Molecular mimicry responsible for anti-parasite-responses that “crossreact” with self-molecules in Trypanosoma cruzi-infected host, epitopes dissemination and polyclonal activation support the autoimmune etiology of the disease. However, in the last years, parasites have been detected in tissues of hosts with chronic infections by using more sensitive techniques and also a correlation among inflammation and parasite antigens and/or DNA has been demonstrated. So, rather than discarding the autoimmune hypothesis, Chagas´ disease is considered as a parasite-induced disorder. This review resumes and analyzes the role of the persistence of parasites, the autoimmunity, as well as other factors possibly involved as microvascular changes and neurogenic alterations, in such a disease that interest both parasitologists and immunologists.Transcurridos más de cien años de su descubrimiento, la patogénesis de la enfermedad de Chagas sigue siendo un tema controvertido. Durante décadas se ha dado mayor relevancia a las consecuencias de la respuesta inmunitaria, hasta el punto de estar considerada como una enfermedad autoinmune. El mimetismo molecular entre antígenos del parásito y del hospedador, la diseminación de epitopos y la activación policlonal son algunos de los mecanismos que explicarían el carácter autoinmune de la enfermedad. Sin embargo, en los últimos años, el interés vuelve a centrarse en el parásito. La utilización de técnicas más sensibles no sólo ha puesto en evidencia su presencia en tejidos, sino que se ha demostrado que existe una correlación entre inflamación y antígenos y/o ADN parasitario. En base a ello, sin descartar la importancia de la respuesta inmune, la necesidad de que persista el parásito está inclinando la balanza hacia consideración como enfermedad parasitaria. Este artículo resume y analiza la participación del parásito, del sistema inmune, así como la influencia de otros factores, como cambios microvasculares o alteraciones neurogénicas, en la patogénesis de una enfermedad que apasiona a parasitólogos e inmunólogos

Valorization of residues from refining of used vegetable oils

This study investigates the advantages of two-phase anaerobic digestion for treating a mixture (1/5 v/v) of used vegetable oils processing wastes and pig manure using two semi-continuous digesters operated at mesophilic temperature (37±1 ºC). The experiments were conducted at hydraulic retention times (HRT) of 0.5, 1, 2 and 4 days in the first stage (acidifier) and at HRT of 11.5, 15, 18 and 20 days in the second stage (methanizer). The results revealed that the HRT had a high influence on the soluble chemical oxygen demand (CODs) and total dissolved solids (TDS) removal. The maximum total CODs removal efficiency of 86.4% and TDS removal efficiency of 81.9% was achieved at 20 days of global HRT. The maximum biogas production of 0.65 m3 per kilogramme of volatile dissolved solids (VDS) removed (65% CH4) was also achieved at 20 days of HRT

Thio- and selenosemicarbazones as antiprotozoal agents against Trypanosoma cruzi and Trichomonas vaginalis

Herein, we report the preparation of a panel of Schiff bases analogues as antiprotozoal agents by modification of the stereoelectronic effects of the substituents on N-1 and N-4 and the nature of the chalcogen atom (S, Se). These compounds were evaluated towards Trypanosoma cruzi and Trichomonas vaginalis. Thiosemicarbazide 31 showed the best trypanocidal profile (epimastigotes), similar to benznidazole (BZ): IC50 (31)=28.72 μM (CL-B5 strain) and 33.65 μM (Y strain), IC50 (BZ)=25.31 μM (CL-B5) and 22.73 μM (Y); it lacked toxicity over mammalian cells (CC50 > 256 µM). Thiosemicarbazones 49, 51 and 63 showed remarkable trichomonacidal effects (IC50 =16.39, 14.84 and 14.89 µM) and no unspecific cytotoxicity towards Vero cells (CC50 ≥ 275 µM). Selenoisosters 74 and 75 presented a slightly enhanced activity (IC50=11.10 and 11.02 µM, respectively). Hydrogenosome membrane potential and structural changes were analysed to get more insight into the trichomonacidal mechanism.Junta de Andalucía Grant PID2020- 116460RB-I00, funded by MCIN/AEI/10.13039/50110001103

Promising hit compounds against resistant trichomoniasis: Synthesis and antiparasitic activity of 3-(ω-aminoalkoxy)-1-benzyl-5-nitroindazoles

A series of 11 3-(ω-aminoalkoxy)-1-benzyl-5-nitroindazoles (2–12) has been prepared starting from 1-benzyl-5-nitroindazol-3-ol 13, and evaluated against sensitive and resistant isolates of the sexually transmitted protozoan Trichomonas vaginalis. Compounds 2, 3, 6, 9, 10 and 11 showed trichomonacidal profiles with IC50 < 20 µM against the metronidazole-sensitive isolate. Moreover, all these compounds submitted to cytotoxicity assays against mammalian cells exhibited low non-specific cytotoxic effects, except compounds 3 and 9 which displayed moderate cytotoxicity (CC50 = 74.7 and 59.1 µM, respectively). Those compounds with trichomonacidal effect were also evaluated against a metronidazole-resistant culture. Special mention deserve compounds 6 and 10, which displayed better IC50 values (1.3 and 0.5 µM respectively) than that of the reference drug (IC50 MTZ = 3.0 µM). The high activity of these compounds against the resistant isolate reinforces the absence of cross-resistance with the reference drug. The remarkable trichomonacidal results against resistant T. vaginalis isolates suggest the interest of 3-(ω-aminoalkoxy)-1-benzyl-5-nitroindazoles to be considered as good prototypes to continue in the development of new drugs with enhanced trichomonacidal activity, aiming to increase the non-existent drugs to face clinical resistance efficiently for those patients in whom therapy with 5-nitroimidazoles is contraindicated

Modelos tridimensionales para el aprendizaje práctico de la Inmunología

Depto. de Microbiología y ParasitologíaFac. de FarmaciaFALSEsubmitte

B-learning en Helmintología: su aplicación al laboratorio virtual

Presentaciones animadas de esquemas morfológicos y ciclos biológico de los principales cestodos y nematodos parásitos del hombr

Synthesis and biological properties of new 5-nitroindazole derivatives

A series of new 3-alkoxy- or 3-hydroxy-1-[ω-(dialkylamino)alkyl]-5- nitroindazoles have been synthesized and their trichomonacidal, antichagasic and antineoplastic properties studied. Five derivatives (5, 6, 8, 9 and 17) showed remarkable trichomonacidal activity against Trichomonas vaginalis at 10 μg/mL concentration. Three compounds (8, 10, 11) exhibited interesting antichagasic activity and these same compounds moderate antineoplastic activity against TK-10 and HT-29 cell lines. Unspecific cytotoxicity against macrophages has also been evaluated and only compounds 9, 10 and 11 resulted cytotoxic at the higher dose evaluated (100 μg/mL), loosing cytotoxicity at lower doses. QSAR studies have been carried out. X-ray crystallographic study of compound 8 has been performed. © 2005 Elsevier Ltd. All rights reserved.Peer Reviewe