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1.
Med Vet Entomol ; 2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39400392

RESUMEN

In Mexico, Triatoma pallidipennis is a major vector of Trypanosoma cruzi, the causative agent of Chagas disease. Current efforts are focused on developing attractants to control these vectors, using volatile substances derived from vertebrate hosts or compounds known to attract hematophagous insects. However, the efficacy of these compounds in attracting parasite-infected triatomines remains to be evaluated. In this study, we assessed the attractant activity of octenol (1-octen-3-ol), nonanal and a mixture of odorants consisting of ammonium hydroxide, lactic acid and hexanoic acid (in a ratio of 1:0.2:0.4 respectively), at concentrations of 1, 10 and 100 ng on the N3, N4 and N5 nymphal stages of T. pallidipennis, both infected and non-infected with T. cruzi. We also evaluated the synergistic effect of the most effective compounds and doses. All experiments were performed in a laboratory using a Y-type glass olfactometer. We found that both infected and non-infected N3 and N4 nymphs were attracted to low doses of octenol, nonanal and the odorant mixture. Particularly noteworthy was the synergistic effect observed between the odorant mixture and nonanal, which significantly increased attraction of T. cruzi-infected individuals. These findings contribute to the development of baited traps utilising these compounds for monitoring triatomines in epidemiological studies or for mass trapping to control these vectors.

2.
Int J Mol Sci ; 25(11)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38892261

RESUMEN

Flatworms are known for their remarkable regenerative ability, one which depends on totipotent cells known as germinative cells in cestodes. Depletion of germinative cells with hydroxyurea (HU) affects the regeneration of the parasite. Here, we studied the reduction and recovery of germinative cells in T. crassiceps cysticerci after HU treatment (25 mM and 40 mM of HU for 6 days) through in vitro assays. Viability and morphological changes were evaluated. The recovery of cysticerci's mobility and morphology was evaluated at 3 and 6 days, after 6 days of treatment. The number of proliferative cells was evaluated using EdU. Our results show morphological changes in the size, shape, and number of evaginated cysticerci at the 40 mM dose. The mobility of cysticerci was lower after 6 days of HU treatment at both concentrations. On days 3 and 6 of recovery after 25 mM of HU treatment, a partial recovery of the proliferative cells was observed. Proteomic and Gene Ontology analyses identified modifications in protein groups related to DNA binding, DNA damage, glycolytic enzymes, cytoskeleton, skeletal muscle, and RNA binding.


Asunto(s)
Proliferación Celular , Hidroxiurea , Taenia , Hidroxiurea/farmacología , Animales , Proliferación Celular/efectos de los fármacos , Taenia/efectos de los fármacos , Taenia/genética , Taenia/crecimiento & desarrollo , Taenia/metabolismo , Proteómica/métodos , Proteínas del Helminto/metabolismo , Proteínas del Helminto/genética , Proteoma/metabolismo , Cysticercus/efectos de los fármacos , Cysticercus/metabolismo
3.
Pathogens ; 12(9)2023 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-37764892

RESUMEN

Symptoms in the acute phase of Chagas disease are usually mild and nonspecific. However, after several years, severe complications like dilated heart failure and even death may arise in the chronic phase. Due to the lack of specific symptoms in the acute phase, the aim of this work was to describe and analyze the cardiac histopathology during this phase in a CD1 mouse model by assessing parasitism, fibrotic damage, and the presence and composition of a cellular infiltrate, to determine its involvement in the pathogenesis of lesions in the cardiac tissue. Our results indicate that the acute phase lasts about 62 days post-infection (dpi). A significant increase in parasitemia was observed since 15 dpi, reaching a maximum at 33 dpi (4.1 × 106). The presence of amastigote nests was observed at 15-62 dpi, with a maximum count of 27 nests at 35 dpi. An infiltrate consisting primarily of macrophages and neutrophils was found in the cardiac tissue within the first 30 days, but the abundance of lymphocytes showed an 8 ≥ fold increase at 40-62 dpi. Unifocal interstitial fibrosis was identified after 9 dpi, which subsequently showed a 16 ≥ fold increase at 40-60 dpi, along with a 50% mortality rate in the model under study. The increased area of fibrotic lesions revealed progression in the extent of fibrosis, mainly at 50-62 dpi. The presence of perivasculitis and thrombus circulation disorders was seen in the last days (62 dpi); finally, cases of myocytolysis were observed at 50 and 62 dpi. These histopathological alterations, combined with collagen deposition, seem to lead to the development of interstitial fibrosis and damage to the cardiac tissue during the acute phase of infection. This study provides a more complete understanding of the patterns of histopathological abnormalities involved in the acute phase, which could help the development of new therapies to aid the preclinical tests of drugs for their application in Chagas disease.

4.
Pathogens ; 12(9)2023 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-37764932

RESUMEN

Chagas disease is caused by the hemoflagellate protozoan Trypanosoma cruzi. The main transmission mechanism for the parasite in endemic areas is contact with the feces of an infected triatomine bug. Part of the life cycle of T. cruzi occurs in the digestive tract of triatomines, where vector and parasite engage in a close interaction at a proteomic-molecular level. This interaction triggers replication and differentiation processes in the parasite that can affect its infectivity for the vertebrate host. With the aim of compiling and analyzing information from indexed publications on transcripts, proteins, and glycoproteins in the guts of fasting, fed, and T. cruzi-infected triatomines in the period 2000-2022, a systematic review was conducted following the PRISMA guidelines. Fifty-five original research articles retrieved from PubMed and ScienceDirect were selected; forty-four papers reported 1-26,946 transcripts, and twenty-one studies described 1-2603 peptides/proteins.

5.
Trop Med Infect Dis ; 8(7)2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37505656

RESUMEN

Chagas disease is one of the most important tropical infections in the world and mainly affects poor people. The causative agent is the hemoflagellate protozoan Trypanosoma cruzi, which circulates among insect vectors and mammals throughout the Americas. A large body of research on Chagas disease has shown the complexity of this zoonosis, and controlling it remains a challenge for public health systems. Although knowledge of Chagas disease has advanced greatly, there are still many gaps, and it is necessary to continue generating basic and applied research to create more effective control strategies. The aim of this review is to provide up-to-date information on the components of Chagas disease and highlight current trends in research. We hope that this review will be a starting point for beginners and facilitate the search for more specific information.

6.
Pathogens ; 12(2)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36839607

RESUMEN

In Chagas disease, the mechanisms involved in cardiac damage are an active field of study. The factors underlying the evolution of lesions following infection by Trypanosoma cruzi and, in some cases, the persistence of its antigens and the host response, with the ensuing development of clinically observable cardiac damage, are analyzed in this review.

7.
Pathogens ; 11(10)2022 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-36297198

RESUMEN

Trypanosoma cruzi is a parasite transmitted by the feces of triatomines. Many triatomine species are found in Mexico, and various T. cruzi variants have been isolated from these species, each showing very different virulence and cell tropism. The isolates were obtained from Meccus phyllosoma specimens in three localities in the state of Oaxaca, Mexico: Tehuantitla, Vixhana, and Guichivere. The virulence of each isolate was assessed by quantifying parasitemia, survival, and histopathologic findings. The lineage of each isolate was identified using the mini-exon gene. The expression of the tssa gene during infection was detected in the heart, esophagus, gastrocnemius, and brain. Our results show that the maximum post-infection parasitemia was higher for the Tehuantitla isolate. On genotyping, all isolates were identified as T. cruzi I. The amastigotes in the heart and gastrocnemius were verified for all isolates, but in the brain only for Tehuantitla and Vixhana. The tssa expression allowed us to detect T. cruzi isolates, for Tehuantitla, predominantly in the heart. For Vixhana, a higher tssa expression was detected in gastrocnemius, and for Guichivere, it was higher in the esophagus. Results show that virulence, tropism, and tssa expression can vary, even when the isolates are derived from the same vector species, in the same region, and at similar altitudes.

8.
Parasit Vectors ; 14(1): 385, 2021 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-34348795

RESUMEN

BACKGROUND: Relatively little is known about how pathogens transmitted by vector insects are affected by changing temperatures analogous to those occurring in the present global warming scenario. One expectation is that, like their ectothermic vectors, an increase in temperature could reduce their fitness. Here, we have investigated the effect of high temperatures on the abundance of Trypanosoma cruzi parasites during infection in the vector Triatoma pallidipennis. METHODS: We exposed T. pallidipennis nymphs to two strains (Morelos and Chilpancingo) of T. cruzi. Once infected, the fifth-instar bugs were distributed among three different temperature groups, i.e. 20, 30, and 34 °C, and the resulting parasites were counted when the bugs reached adulthood. RESULTS: The number of parasites increased linearly with time at 20 °C and, to a lesser extent, at 30 °C, especially in the Chilpancingo compared to the Morelos strain. Conversely, at 34 °C, the number of parasites of both strains decreased significantly compared to the other two temperatures. CONCLUSIONS: These results suggest negative effects on the abundance of T. cruzi in T. pallidipennis at high temperatures. This is the first evidence of the effect of high temperatures on a pathogenic agent transmitted by an insect vector in the context of global warming. Further tests should be done to determine whether this pattern occurs with other triatomine species and T. cruzi strains.


Asunto(s)
Insectos Vectores/parasitología , Triatoma/parasitología , Trypanosoma cruzi/fisiología , Animales , Cambio Climático , Femenino , Calor , Modelos Lineales , Masculino , México , Ratones , Ninfa/parasitología , Recto/parasitología , Factores de Tiempo
9.
Front Vet Sci ; 7: 568745, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33134353

RESUMEN

Cardiopathy is a common, irreversible manifestation of the chronic phase of Chagas disease; however, there is controversy as to how the causes for progression from the acute to the chronic phase are defined. In this work, the presence of the parasite is correlated with the occurrence of cell infiltration and fibrosis in cardiac tissues, as well as IgG detection and disease progression in a murine model. Fifty CD1 mice were infected intraperitoneally with Trypanosoma cruzi, while 30 control were administered with saline solution. Parasitemia levels were determined, and IgG titers were quantified by ELISA. At different times, randomly selected mice were euthanized, and the heart was recovered. Cardiac tissue slides were stained with HE and Masson trichrome stain. A significant increase in parasitemia levels was observed after 15 days post-infection (dpi), with a maximum of 4.1 × 106 parasites on 33 dpi, ending on 43 dpi; amastigote nests were observed on 15-62 dpi. Histological analysis revealed lymphocytic infiltration and fibrotic lesions from 8 dpi until the end of the study, on 100 dpi. The presence of plasma cells in the myocardium observed on 40-60 dpi, accompanied by seropositivity to ELISA on 40-100 dpi, was regarded as the hallmark of the transition phase. Meanwhile, the chronic phase, characterized by the absence of amastigotes, presence of cell infiltration, fibrotic lesions, and seropositivity, started on 62 dpi. A strong correlation between parasitemia and the presence of amastigote nests was found (r 2 = 0.930), while correlation between the presence of fibrosis and of amastigote nests was weak (r 2 = 0.306), and that between fibrosis and lymphocyte infiltration on 100 dpi was strong (r 2 = 0.899). The murine model is suitable to study Chagas disease, since it can reproduce the chronic and acute phases of the human disease. The acute phase was determined to occur on 1-60 dpi, while the chronic phase starts on 62 dpi, and fibrotic damage is a consequence of the continuous inflammatory infiltration; on the other hand, fibrosis was determined to start on the acute phase, being more apparent in the chronic phase, when Chagas disease-related cardiopathy is induced.

10.
Bull Entomol Res ; 110(3): 363-369, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31690355

RESUMEN

Triatomine bugs carry the parasitic protozoa Trypanosoma cruzi, the causal agent of Chagas disease. It is known that both the parasite and entomopathogenic fungi can decrease bug survival, but the combined effect of both pathogens is not known, which is relevant for biological control purposes. Herein, the survival of the triatomine Meccus pallidipennis (Stal, 1872) was compared when it was coinfected with the fungus Metarhizium anisopliae (Metschnikoff) and T. cruzi, and when both pathogens acted separately. The immune response of the insect was also studied, using phenoloxidase activity in the bug gut and hemolymph, to understand our survival results. Contrary to expectations, triatomine survival was higher in multiple than in single challenges, even though the immune response was lower in cases of multiple infection. We postulate that T. cruzi exerts a protective effect and/or that the insect reduced the resources allocated to defend itself against both pathogens. Based on the present results, the use of M. anisopliae as a control agent should be re-considered.


Asunto(s)
Coinfección , Metarhizium/patogenicidad , Triatominae/microbiología , Triatominae/parasitología , Trypanosoma cruzi/patogenicidad , Animales , Agentes de Control Biológico , Enfermedad de Chagas/prevención & control , Insectos Vectores/microbiología , Insectos Vectores/parasitología , Ratones , Monofenol Monooxigenasa/metabolismo , Ninfa/inmunología , Ninfa/microbiología , Ninfa/parasitología , Triatominae/enzimología , Triatominae/inmunología
11.
Rev Med Inst Mex Seguro Soc ; 57(2): 97-106, 2019 Jul 31.
Artículo en Español | MEDLINE | ID: mdl-31618564

RESUMEN

Background: Educational curricula require constant improvement to respond to the needs of students, institutions and society. Objective: To evaluate the Plan de Estudios 2010 of the Facultad de Medicina de la Universidad Nacional Autónoma de México. Methods: Documentary and qualitative study of three phases. First, revision of trends of general medicine in special databases and comparison of curricula between universities. Second, focus groups with clinical teachers and basic sciences to investigate experiences and opinions in relation to trends in general medicine. Third, a "Generalists Committee" was convened to whom the results were presented (phase one and two) and the recommendations were adapted to adapt the results to the general practitioner's context. The participants were informed about the research objective and their participation was voluntary, the anonymity of theirs comments was protected. Results: The trend towards specialization in clinical practice defines the future of general medicine, and the administrative uses have an impact on the practices of the general practitioner and on the patient's medical relationship. Conclusion: Various aspects mainly educational and assistance hindered the quality of the practice of general medicine.


Introducción: los currículos educativos requieren estar en constante perfeccionamiento para responder a las necesidades de estudiantes, instituciones y de la sociedad. Objetivo: evaluar el Plan de Estudios 2010 de la carrera de medicina de la Facultad de Medicina de la Universidad Nacional Autónoma de México. Métodos: estudio documental y cualitativo, de tres fases. En la primera se revisaron las tendencias de la medicina general en bases de datos especializadas y se compararon los planes de estudios entre universidades. En la segunda, se realizaron grupos focales con docentes clínicos y de ciencias básicas para indagar experiencias y opiniones en relación con las tendencias de la medicina general. En la tercera, se convocó a un "Comité de Generalistas" a quienes se les presentaron los resultados de las fases anteriores, y se realizaron las recomendaciones pertinentes para adecuar los resultados al contexto del médico general. La participación de los entrevistados fue voluntaria, fueron informados sobre el objetivo de investigación y se resguardó el anonimato de sus testimonios. Resultados: la tendencia hacia la especialidad en la práctica clínica define el futuro de la medicina general; asimismo, los intereses administrativos repercuten en las prácticas del médico general y en la relación médico-paciente. Conclusión: diversos aspectos, principalmente educativos y asistenciales, obstaculizan la calidad de la práctica de la medicina general.


Asunto(s)
Medicina General/educación , Médicos Generales/educación , Comités Consultivos/organización & administración , Curriculum , Grupos Focales , Medicina General/normas , Medicina General/tendencias , Humanos , México , Facultades de Medicina
12.
Parasit Vectors ; 12(1): 219, 2019 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-31068226

RESUMEN

BACKGROUND: Little is known about how human disease vectors will modify their life history patterns and survival capacity as a result of climate change. One case is that of Chagas disease, which has triatomine bugs and Trypanosoma cruzi as vectors and parasite, respectively. This work aimed to determine: (i) the activity of the prophenoloxidase system (prophenoloxidase and phenoloxidase activity, two indicators of immune ability) in three intestine regions (anterior midgut, posterior midgutand rectum) of the triatomine bug Meccus pallidipennis under three temperature conditions (20 °C, 30 °C and 34 °C) against two T. cruzi strains [ITRI/MX/14/CHIL (Chilpancingo) and ITRI/MX/12/MOR (Morelos)], and (ii) whether vector survival varies under these three temperatures after infection by these T. cruzi strains. RESULTS: Our results indicate that prophenoloxidase activity was lower at higher temperatures, that the level of prophenoloxidase activity elicited by each strain was different (higher in Chilpancingo than in Morelos strains), and that prophenoloxidase activity was more intense in the anterior midgut than in the posterior midgut or rectum. Survival rates were lower in insects maintained at higher temperatures and infected by Chilpancingo strains. CONCLUSIONS: These results indicate that climate change could lead to lower prophenoloxidase activity and survival rates in triatomines when infected with different T. cruzi strains, which could reduce the vector capacity of M. pallidipennis.


Asunto(s)
Catecol Oxidasa/metabolismo , Cambio Climático , Precursores Enzimáticos/metabolismo , Temperatura , Triatoma/parasitología , Trypanosoma cruzi/fisiología , Animales , Femenino , Tracto Gastrointestinal/anatomía & histología , Tracto Gastrointestinal/parasitología , Insectos Vectores/enzimología , Insectos Vectores/parasitología , Masculino , Triatoma/enzimología
13.
Artículo en Inglés | MEDLINE | ID: mdl-30984116

RESUMEN

Originally an anthropozoonosis in the Americas, Chagas disease has spread from its previous borders through migration. It is caused by the protozoan Trypanosoma cruzi. Differences in disease severity have been attributed to a natural pleomorphism in T. cruzi. Several post-translational modifications (PTMs) have been studied in T. cruzi, but to date no work has focused on O-GlcNAcylation, a highly conserved monosaccharide-PTM of serine and threonine residues mainly found in nucleus, cytoplasm, and mitochondrion proteins. O-GlcNAcylation is thought to regulate protein function analogously to protein phosphorylation; indeed, crosstalk between both PTMs allows the cell to regulate its functions in response to nutrient levels and stress. Herein, we demonstrate O-GlcNAcylation in T. cruzi epimastigotes by three methods: by using specific antibodies against the modification in lysates and whole parasites, by click chemistry labeling, and by proteomics. In total, 1,271 putative O-GlcNAcylated proteins and six modification sequences were identified by mass spectrometry (data available via ProteomeXchange, ID PXD010285). Most of these proteins have structural and metabolic functions that are essential for parasite survival and evolution. Furthermore, O-GlcNAcylation pattern variations were observed by antibody detection under glucose deprivation and heat stress conditions, supporting their possible role in the adaptive response. Given the numerous biological processes in which O-GlcNAcylated proteins participate, its identification in T. cruzi proteins opens a new research field in the biology of Trypanosomatids, improve our understanding of infection processes and may allow us to identify new therapeutic targets.

14.
Bioorg Chem ; 86: 452-458, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30772646

RESUMEN

The increasing use of dendrimers shows promise for the treatment of inflammatory diseases, Chagas disease and other conditions such as cancer. In this study, the activity of 1st and 2nd generation dendrimers over T. cruzi in the epimastigote stage was tested. Dendrimers were derived from α-ethynylestradiol (EE) modified with PAMAM-type dendrons through a triazole ring. The activity of each compound was evaluated in five doses (from 1.3 to 20 µmol/mL) by flow cytometry, including benznidazole (Bz) as positive control. The findings show that an equivalent concentration of 14.8 µmol/mL of 2nd generation (G) dendrimer is 8 times more effective than Bz at 24 h, and it maintains its superiority at 48 h with an IC50 = 1.25 ±â€¯0.19 µmol/mL. A TUNEL assay showed that dendrimers induce cell death in T. cruzi epimastigotes mostly via apoptosis, unlike Bz, which induces death via necrosis in more than 50% of cells.


Asunto(s)
Dendrímeros/farmacología , Poliaminas/farmacología , Esteroides/farmacología , Trypanosoma cruzi/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Química Clic , Dendrímeros/síntesis química , Dendrímeros/química , Relación Dosis-Respuesta a Droga , Humanos , Linfocitos/efectos de los fármacos , Estructura Molecular , Pruebas de Sensibilidad Parasitaria , Poliaminas/química , Esteroides/síntesis química , Esteroides/química , Relación Estructura-Actividad , Trypanosoma cruzi/crecimiento & desarrollo
15.
Acta Trop ; 178: 134-141, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29180164

RESUMEN

In Chagas disease the clinical, acute and chronic manifestations are the result of the interaction between the parasite and the host factors. The balance between inflammatory and anti-inflammatory immune responses is essential for the increase or resolution of the manifestations in individuals infected with T. cruzi. To identify if children with chronic Chagas disease and heart injury is related with non-regulated Th1, Th2 and Th17 responses. We included 31 children with T. cruzi confirmed chronic infection from endemic areas of Mexico. Subsequently, they were separated according to their ECHO and ECG results into three groups according to the severity of cardiac involvement. Circulating Th1, Th2 and Th17 cytokine profiles were performed by Luminex assays and the results were analyzed by bivariate and multivariable analysis. Patients were classified in asymptomatic chronic (group 1, N=12); individuals with IRBBB in ECG and incipient lesions in ECHO (Group 2, N=8) and Patients with severe chronic symptomatic disease (Group 3, N=11). The analysis of immune mediators revealed that patients with severe cardiac manifestations had significant higher levels (p <0.05) of Th17 related cytokines including IL-17 and IL-6 as well as IFN-γ and IL-2. Also patients with severe cardiomyopathy exhibit increased levels of IL-13 (p <0.05) after multivariate analysis. High levels of Th17 related cytokines including IL-17, IFN-γ, IL-6 and IL-2 and pro-fibrotic factors such as IL-13 could be associated to the severity of cardiac involvement in children with chronic T. cruzi infection. These cytokines could be useful as indicators for the early identification of cardiac damage associated to the T. cruzi infection.


Asunto(s)
Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/patología , Citocinas/sangre , Enfermedades Endémicas , Trypanosoma cruzi/inmunología , Animales , Biomarcadores/sangre , Enfermedad de Chagas/sangre , Enfermedad de Chagas/parasitología , Niño , Femenino , Humanos , Masculino , México/epidemiología
16.
Tohoku J Exp Med ; 240(3): 243-249, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27890871

RESUMEN

Chagas disease is a parasitic infection mainly found in Latin America; it is transmitted by a triatomine, also known as assassin bug or kissing bug. In humans, the parasite causes mostly cardiac disorders. Two-thirds of the Mexican territory are regarded as risk areas for vector transmission of Trypanosoma cruzi, the causal agent. The parasite can be found as a blood-borne trypomastigote or as an intracellular amastigote. The progression and severity of lesions could be due to frequent reinfections or to infection by highly virulent strains. A total of 3,327 individuals younger than 18 years old, living in risk areas for this disease in the rural setting of the States of Queretaro, San Luis Potosi, and Veracruz, underwent a seroepidemiological study. Among them, 37 subjects were seropositive for T. cruzi, and were studied to look for signs of cardiac pathology, which has only been reported in adults. A clinical record was prepared for all included individuals, and electrocardiography (ECG) and echocardiography (ECHO) studies were performed; 25 cases showed lesions compatible with the onset of Chagas cardiomyopathy. The other 12 patients showed either normal ECG and ECHO data or showed abnormal parameters that were not regarded as significant. Lesions found in the onset of Chagas cardiomyopathy in children are herein reported, along with 14 cases of cardiac pathology compatible with Chagas disease. Our results indicate that patients younger than 18 years can show a cardiac pathology similar to that observed in adults.


Asunto(s)
Cardiomiopatía Chagásica/epidemiología , Adolescente , Cardiomiopatía Chagásica/diagnóstico por imagen , Niño , Preescolar , Ecocardiografía , Electrocardiografía , Femenino , Geografía , Humanos , Masculino , México/epidemiología
17.
Rev. Fac. Med. UNAM ; 59(3): 6-16, may.-jun. 2016. graf
Artículo en Español | LILACS | ID: biblio-957088

RESUMEN

Resumen México es un país endémico para la enfermedad de Chagas, donde dos terceras partes del territorio pueden ser consideradas en riesgo de transmisión vectorial, es decir que 1'100,000 individuos podrían estar infectados con Trypanosoma cruzi y 29'500,000 en riesgo de contraer la infección. En la morbimortalidad del padecimiento son importantes las características de la vivienda, condiciones biológicas, ambientales y factores socioculturales. El tamizaje en bancos de sangre, a la fecha, es de observancia obligatoria con una cobertura mayor al 92%. El diagnóstico no se establece frecuentemente debido al desconocimiento de la enfermedad por parte del personal de salud y de la población. La fase aguda generalmente pasa desapercibida y en la crónica, la patología se presenta principalmente en el corazón, con evolución lenta. La patogénesis de la miocardiopatía crónica es muy compleja y se presentan lesiones con mayor frecuencia en el sistema nervioso autónomo y miocardio, lo que genera trastornos en la conductibilidad y contractilidad del órgano. Se describen los principales mecanismos patogénicos implicados en el desarrollo de la enfermedad.


Abstract Mexico is a country endemic for Chagas disease in which two thirds of the territory can be considered at risk of vector-borne infection. This means that 1.1 million people could be infected with Trypanosoma cruzi and 29.5 million at risk of infection. Dwelling characteristics of poverty in these rural areas linked with biological conditions, lifestyle, environmental and sociocultural factors are important in the morbidity and mortality of the disease. Nowadays, the screening for the parasite is mandatory and at least 92% of blood banks are covered. The inadequate knowledge of the disease by the health personnel and the population limits the possibility of the diagnosis. The acute phase of the disease courses undetected. The main affected organ in Chagas disease is the heart, with a slow evolution; the pathogenesis of chronic cardiomyopathy is complex and lesions occur mainly in the autonomic nervous system and myocardium leading to disturbances in the conductivity and contractility of the organ. The main pathogenic mechanisms involved in the development of the disease are described.

18.
Parasit Vectors ; 9: 176, 2016 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-27012246

RESUMEN

BACKGROUND: Chagas disease is a key health problem in Latin America and is caused and transmitted by Trypanosoma cruzi and triatomine bugs, respectively. Control of triatomines has largely relied on the use pyrethroids, which has proved to be ineffective in the long term. Alternatively, the use of entomopathogenic fungi has been implemented to control triatomine bugs. These fungi are highly efficient as they induce a reduction in immune response on insects. Meccus pallidipennis is the main triatomine vector of Chagas disease in Mexico. In this work we investigated the effects of two entomopathogenic fungi, Metarhizium anisopliae and Isaria fumosorosea, on M. pallidipennis nymphs in terms of insect survival and immune response. METHODS: We had an infected and a control group for each fungal species and assessed: a) insect survival during 30 days; and, b) phenoloxidase (PO) and prophenoloxidase (proPO; two key traits in insect immune response) at 24, 48, 96 and 144 h. For survival we used Kaplan-Meier survival analysis while for immune response we used factorial, repeated-measures ANOVA for each fungal species. RESULTS: Animals treated with M. anisopliae died sooner than animals treated with I. fumosorosea. Infected animals showed lower PO and proPO values than sham individuals, with a clear decrease in these parameters at 24 h with no further changes after this time. CONCLUSIONS: Our study widens the possibility of entomopathogenic fungi being used for triatomine control. The negative effect on PO and proPO seems mediated by a down-regulation of the triatomine immune response.


Asunto(s)
Hypocreales/patogenicidad , Insectos Vectores , Metarhizium/patogenicidad , Triatominae/inmunología , Triatominae/microbiología , Animales , Control de Enfermedades Transmisibles/métodos , México , Ninfa/inmunología , Ninfa/microbiología , Control Biológico de Vectores/métodos , Análisis de Supervivencia
19.
Gac Med Mex ; 151(1): 6-13, 2015.
Artículo en Español | MEDLINE | ID: mdl-25739478

RESUMEN

INTRODUCTION: Conventional serology was used for the detection of Trypanosoma cruzi infection, with diverse sensitivity and specificity results. Due to the number of samples with doubtful results, it is necessary to develop additional confirmation tests such as the immunoblot. OBJECTIVE: The aim of this study was identify major immunogenic proteins of T. cruzi isolate and establish criteria for immunoblot positivity with diagnostic purposes. METHODS: Immunoblot initial standardization was performed, determining optimal concentrations of antigen, serum, and second antibody. Thirty-five positive and thirty negative sera were assayed to evaluate different criteria of positivity and determine which provides greater sensitivity and specificity. RESULTS: Immunoblot of T. cruzi positive sera shared a rich pattern of components with molecular weights between 10-250 kDa. Twelve components had a recognition rate higher than 50%, of which the polypeptides of 27, 32, 34, and 38 kDa were close to 100%. Of the positivity criteria evaluated, the recognition of the components of 27 and 32 kDa provided sensitivity and specificity of 100%. DISCUSSION: The Immunoblot is suitable for confirmation of infection by T. cruzi, so it is strongly recommended for confirmation and discrimination of discordant cases.


Asunto(s)
Western Blotting/métodos , Enfermedad de Chagas/diagnóstico , Trypanosoma cruzi/aislamiento & purificación , Enfermedad de Chagas/inmunología , Electroforesis en Gel de Poliacrilamida/métodos , Humanos , Sensibilidad y Especificidad , Trypanosoma cruzi/inmunología
20.
Eur J Med Chem ; 87: 23-9, 2014 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-25238291

RESUMEN

In this study thiosemicarbazones derivatives of 5-[(trifluoromethyl)phenylthio]-2-furaldehyde were synthesized and evaluated in terms of their efficiency in challenging the growth of epimastigote forms of Trypanosoma cruzi, the etiological agent of Chagas' disease. A number of compounds were synthesized from 5-bromo-2-furfuraldehyde using nucleophilic aromatic substitution, with a series of trifluoromethyl thiolates, followed by condensation reactions with thiosemicarbazide. Their molecular structures were determined by (1)H, (13)C and (19)F NMR, MS and IR spectroscopy. When tested with T. cruzi, they showed a stronger reaction, similar to nifurtimox and benznidazole, with the 5-[nitro-4-(trifluoromethyl)phenyltio]-2-furaldehyde thiosemicarbazone (compound 4) showing the highest antiparasitic activity. This improved activity may be explained due to the nitro group present in the molecule, which potentiates its activity. The thiosemicarbazone derivatives in this study showed no apoptosis in platelets or monocytes, nor did they induce platelet activation. The trypanocidal activity of these substances represents a good starting point for a medicinal chemistry program aimed at therapy for Chagas' disease.


Asunto(s)
Plaquetas/efectos de los fármacos , Enfermedad de Chagas/tratamiento farmacológico , Monocitos/efectos de los fármacos , Activación Plaquetaria/efectos de los fármacos , Tiosemicarbazonas/química , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Apoptosis/efectos de los fármacos , Plaquetas/parasitología , Células Cultivadas , Citometría de Flujo , Humanos , Técnicas In Vitro , Estructura Molecular , Monocitos/parasitología , Tripanocidas/química
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