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1.
Eur J Clin Microbiol Infect Dis ; 40(12): 2633-2638, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34059933

RESUMEN

In order to improve the diagnosis of giardiasis, fecal samples (high/medium/low concentration of cysts) were processed by the parasitological methods used in the routine: Faust, Lutz e Ritchie modified (replacement of formaldehyde by distilled water). The cysts were quantified; the DNA was extracted and amplified by semi-nested PCR (GDH gene). Fifteen clinical samples were analyzed to validate the study by PCR-RFLP. The results showed that the parasite was only detected and genotyped correctly when samples from children with high, medium, and low parasitic load, belonging to genotype AII, were processed by the modified Ritchie method, different from what was observed for the other methods used in laboratory routine (Faust and Lutz). The modified Ritchie method proved to be more suitable, recovering a greater number of cysts from samples, regardless of parasitic load, which reduces the chance of false negative results and has epidemiological repercussions since individuals with low parasite load are usually asymptomatic and the main disseminators of this infection.


Asunto(s)
Técnicas de Genotipaje/métodos , Giardia lamblia/crecimiento & desarrollo , Giardia lamblia/aislamiento & purificación , Giardiasis/parasitología , Reacción en Cadena de la Polimerasa/métodos , Preescolar , Heces/parasitología , Femenino , Genotipo , Giardia lamblia/genética , Giardiasis/diagnóstico , Humanos , Lactante , Estadios del Ciclo de Vida , Masculino , Técnicas de Diagnóstico Molecular/métodos , Carga de Parásitos , Proteínas Protozoarias/genética
2.
Exp Parasitol ; 228: 108136, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34280400

RESUMEN

Strains of Trypanosoma cruzi, etiological agent of Chagas disease, are classified into different discrete typing units that may present distinct dynamics of infection and susceptibility to benznidazole (BZ) treatment. Mice that were orally inoculated with T. cruzi IV strains exhibited a more intense course of infection compared with intraperitoneally inoculated mice, reflected by higher parasite loads. We evaluated the efficacy of BZ treatment in Swiss mice that were inoculated with T. cruzi IV strains from the Western Brazilian Amazon. The mice were orally (OR) or intraperitoneally (IP) inoculated with 2 × 106 culture-derived metacyclic trypomastigotes of the AM14, AM16, AM64, and AM69 strains of T. cruzi that were obtained from two outbreaks of orally acquired acute Chagas disease in the state of Amazonas, Brazil. The animals were treated with BZ (100 mg/kg/day for 20 days). Fresh blood examination, hemoculture, conventional and quantitative real-time polymerase chain reaction were performed to monitor the therapeutic effects of BZ. Significant reductions in five of 24 parameters of parasitemia and parasite load were found in different tissues in the OR group, indicating worse response to BZ treatment compared with the IP group, in which significant reductions in nine of those 24 parameters were observed. The cure rates in the OR groups ranged from 18.2% (1/11) to 75.0% (9/12) and in the IP groups from 58.3% (7/12) to 91.7% (11/12), for the AM14 and AM69 strains, respectively. These findings indicate that treatment with BZ had fewer beneficial effects with regard to reducing parasitemia and parasite load in different tissues of mice that were OR inoculated with four TcIV strains compared with IP inoculation. Therefore, the route of infection with T. cruzi should be considered when evaluating the therapeutic efficacy of BZ in patients with Chagas disease.


Asunto(s)
Enfermedad de Chagas/parasitología , Nitroimidazoles/uso terapéutico , Tripanocidas/uso terapéutico , Trypanosoma cruzi/clasificación , Pared Abdominal/parasitología , Animales , Brasil/epidemiología , Enfermedad de Chagas/tratamiento farmacológico , Enfermedad de Chagas/epidemiología , Esófago/parasitología , Corazón/parasitología , Ratones , Nitroimidazoles/farmacología , Carga de Parásitos , Parasitemia/tratamiento farmacológico , Parasitemia/epidemiología , Parasitemia/parasitología , Estómago/parasitología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos
3.
Mol Biol Rep ; 47(2): 1233-1239, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31813130

RESUMEN

Molecular detection of Giardia duodenalis by polymerase chain reaction (PCR) is difficult in faecal samples due to inhibitors that contaminate DNA preparations, or due to low cyst concentrations. In order to eliminate inhibitors, improve cyst recovery and molecular detection of G. duodenalis, different types of water, distillates (MDs), deionized (MDz), injection (MI) or Milli-Q® (MM) were used instead of formaldehyde (F) in the laboratory routine method (Ritchie). Cysts were isolated from faecal samples with low cyst concentrations (< 1 cyst/field), medium (1-2 cysts/field) or high (> 2 cysts/field). Cyst recovery was improved using all water types (MDs, MDz, MI, MM) compared to formaldehyde. At all cyst concentrations, the use of MM consistently showed the greatest recovery of G. duodenalis cysts . DNA samples from recovered cysts were tested for the glutamate dehydrogenase (GDH) and ß-giardin (ßg) genes. The use of Milli-Q® water allowed to detect both genes in all cyst concentrations, including low. The method processed with the other types of water amplified these genes at high and medium cyst concentrations. GDH and ßg genes were not detected when the sample was processed with formaldehyde. These experimental results were confirmed in clinical samples. The results suggest that Milli-Q® water provides the highest cyst recovery from stool samples and, correspondingly, the highest sensitivity for detecting G. duodenalis by microscopy or PCR for GDH and ßg genes, even at low concentration of cysts.


Asunto(s)
Heces/parasitología , Giardia lamblia/genética , Giardiasis/diagnóstico , Giardiasis/parasitología , Técnicas de Diagnóstico Molecular , Genotipo , Giardia lamblia/crecimiento & desarrollo , Glutamato Deshidrogenasa/genética , Humanos , Reacción en Cadena de la Polimerasa , Proteínas Protozoarias/genética
4.
Parasitol Res ; 117(8): 2403-2410, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29858942

RESUMEN

Mixed infections with Trypanosoma cruzi and Trypanosoma rangeli and their different genetic groups occur frequently in vertebrate hosts and are difficult to detect by serology. In the present study, we evaluated the limit of detection of polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) analysis of cytochrome oxidase II (COII) for the identification of genetic groups of these two parasites in blood and tissue from vertebrate hosts. Reconstitution experiments were performed using human blood (TcI/TcII and KP1+/KP1-) and mouse tissue (TcI/TcII). We tested blood from patients who were in the chronic phase of Chagas disease and tissue from animals that were experimentally infected with all possible combinations of six discrete typing units. In blood samples, T. cruzi and T. rangeli were detected when 5 parasites (pa) were present in the sample, and genetic groups were identified when at least 50 pa were present in the sample. T. cruzi alone could be detected with 1 pa and genotyped (TcI/TcII) with 2 pa. T. rangeli was detected with 2 pa and genotyped (KP+/KP1-) with 25 pa. The present method more readily detected TcII and KP1- in both admixtures and alone. In mouse tissue, TcI and TcII were detected with at least 25 pa. The analysis of blood samples from patients and tissue from animals that were experimentally infected revealed low parasite loads in these hosts, which were below the limit of detection of the present method and could not be genotyped. Our findings indicate that the performance of PCR/RFLP analysis of COII is directly related to the amount and proportion of parasites that are present in the sample and the genetic groups to which the parasites belong.


Asunto(s)
Enfermedad de Chagas/parasitología , Enfermedad de Chagas/veterinaria , Complejo IV de Transporte de Electrones/genética , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de Restricción , Proteínas Protozoarias/genética , Trypanosoma cruzi/aislamiento & purificación , Trypanosoma rangeli/aislamiento & purificación , Animales , Genotipo , Humanos , Límite de Detección , Ratones , Enfermedades de los Roedores/parasitología , Trypanosoma cruzi/enzimología , Trypanosoma cruzi/genética , Trypanosoma rangeli/enzimología , Trypanosoma rangeli/genética
5.
Exp Parasitol ; 176: 8-15, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28212811

RESUMEN

Trypanosoma cruzi is the etiologic agent of American trypanosomiasis has broad biological and genetic diversity. Remaining to be studied are polymorphisms of the blood forms and metacyclogenesis of different T. cruzi discrete typing units (DTUs). Our goal was to evaluate the relationship between T. cruzi DTUs, the morphology of blood trypomastigotes, and in vitro metacyclogenesis. T. cruzi strains that pertained to DTUs TcI, TcII, and TcIV from different Brazilian states were used. Parameters that were related to the morphology of eight strains were assessed in thin blood smears that were obtained from mice that were inoculated with blood or culture forms, depending on strain. The metacyclogenesis of 12 strains was measured using smears with Liver Infusion Tryptose culture medium and M16 culture medium (which is poor in nutrients and has a low pH) at the exponential phase of growth, both stained with Giemsa. The morphological pattern of TcII strains was consistent with broad forms of the parasite. In TcIV strains, slender forms predominated. The Y strain (TcII) was morphologically more similar to TcIV. Significant differences in polymorphisms were observed between DTUs. Metacyclogenesis parameters, although displaying large standard deviations, differed between the DTUs, with the following descending rank order: TcII > TcI > TcIV. The mean numbers of metacyclic trypomastigotes for TcII were significantly higher than the other DTUs. Although the DTUs presented overlapping characteristics, the general pattern was that different DTUs exhibited significantly different morphologies and metacyclogenesis, suggesting that the genetic diversity of T. cruzi could be related to parameters that are associated with the evolution of infection in mammalian hosts and its ability to disperse in nature.


Asunto(s)
Enfermedad de Chagas/parasitología , Parasitemia/parasitología , Polimorfismo Genético , Trypanosoma cruzi/genética , Animales , Brasil/epidemiología , Enfermedad de Chagas/sangre , Enfermedad de Chagas/epidemiología , Humanos , Ratones , Zarigüeyas , Parasitemia/sangre , Parasitemia/epidemiología , Rhodnius , Trypanosoma cruzi/clasificación , Trypanosoma cruzi/crecimiento & desarrollo
6.
Parasitol Res ; 116(3): 939-944, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28039497

RESUMEN

In this study were proposed different protocols for the treatment of mice naturally infected with Giardia muris. Male Swiss mice were divided into seven groups, with five animals each, in a blind, controlled, randomized by drawing lots and once-repeated experiment. Parasite detection and cure control were performed using the Faust method and search by trophozoites in the intestinal mucosa. Clinical parameters (weight, water and feed consumption, elimination of excreta, aspect of the fur and feces) were also evaluated. All animals were treated with metronidazole (M), fenbendazole (F), and probiotics (P), administered intragastrically, during 7 days. M1, FM1, and F1 groups were treated 1×/day; M3, FM3, and PM3 groups 3×/day; and ST (control group) received only water. After the 5th and 7th days of treatment, the animals in FM1/FM3 and PM3/M3 groups presented, respectively, negative results and remained negative in the following 10 days. Animals in F1 group consumed less water (p = 0.00010) compared with FM1/FM3/PM3. The animals in M1 group compared with FM3/M3, F1 compared with M3, and ST compared with FM1/FM3/M3/PM3 consumed a larger amount of feed (p = 0.00001). The animals in F1 group compared with FM3/M1/M3/PM3, FM1 compared with FM3, and ST compared with FM3/M1/M3/PM3 eliminated lower volume of excreta (p = 0.00001). The results show that the association between F and M potentiates the effects, indicating a synergistic action of these two drugs, and FM1 is the best protocol due to early negativity in the animals, lower concentrations of the drugs, lower risk of toxicity and stress, and less alterations in clinical parameters.


Asunto(s)
Antiprotozoarios/administración & dosificación , Fenbendazol/administración & dosificación , Giardia/efectos de los fármacos , Giardiasis/tratamiento farmacológico , Metronidazol/administración & dosificación , Animales , Peso Corporal/efectos de los fármacos , Sinergismo Farmacológico , Heces/parasitología , Femenino , Giardia/fisiología , Giardiasis/parasitología , Giardiasis/fisiopatología , Humanos , Mucosa Intestinal/parasitología , Masculino , Ratones , Trofozoítos/efectos de los fármacos , Trofozoítos/fisiología
7.
Exp Parasitol ; 166: 44-50, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26995535

RESUMEN

Trypanosoma cruzi is the etiological agent of American trypanosomiasis (Chagas' disease), which affects 6-7 million people worldwide, mainly in Latin America. It presents great genetic and biological variability that plays an important role in the clinical and epidemiological features of the disease. Our working hypothesis is that the genetic diversity of T. cruzi has an important impact on detection of the parasite using diagnostic techniques. The present study evaluated the diagnostic performance of parasitological, molecular, and serological techniques for detecting 27 strains of T. cruzi that belonged to discrete typing units (DTUs) TcI (11 strains), TcII (four strains), and TcIV (12 strains) that were obtained from different hosts in the states of Amazonas and Paraná, Brazil. Blood samples were taken from experimentally infected mice and analyzed by fresh blood examination, hemoculture in Liver Infusion Tryptose (LIT) medium, polymerase chain reaction (PCR), and enzyme-linked immunosorbent assay (ELISA). Polymerase chain reaction presented the best detection of TcI, with 80.4% positivity. For all of the detection methods, the animals that were inoculated with TcII presented the highest positivity rates (94.1-100%). ELISA that was performed 7 months after inoculation presented a higher detection ability (95.4%) for TcIV. Intra-DTU comparisons showed that the reproducibility of the majority of the results that were obtained with the different methods was weak for TcI and good for TcII and TcIV. Our data indicate that the detection capability of different techniques varies with the DTUs of the parasites in mammalian blood. The implications of these findings with regard to the diagnosis of human T. cruzi infection are discussed.


Asunto(s)
Enfermedad de Chagas/parasitología , Parasitemia/parasitología , Trypanosoma cruzi/aislamiento & purificación , Animales , Brasil , Enfermedad de Chagas/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Humanos , Masculino , Ratones , Parasitemia/diagnóstico , Reacción en Cadena de la Polimerasa , Sensibilidad y Especificidad , Trypanosoma cruzi/genética , Trypanosoma cruzi/inmunología
8.
Int J Environ Health Res ; 26(5-6): 600-5, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27604245

RESUMEN

Toxoplasma gondii oocysts are an important form of contamination with a high dispersion in the environment, but their detection is still a challenge. This study evaluated the recovery of oocysts from strawberries and crisphead lettuce. Samples (250 g of strawberries or one head of lettuce) were experimentally inoculated with 10, 10(2), 10(3) and 10(4) T. gondii oocysts, by two separate processes, spot dripping and immersion. Then, 50 g of each sample was washed, filtered through a cellulose ester membrane, and concentrated by centrifugation. Three aliquots were taken for DNA extraction in a direct way, after freeze-thaw (FT) cycles or ultrasound (US), followed by PCR (B22-B23 and Tox4-Tox5 primers). The T. gondii DNA was amplified with the primers B22-B23 in all samples contaminated by dripping and when DNA extraction was carried out after FT or US. These techniques may be useful in epidemiological surveillance in the control of this zoonosis.


Asunto(s)
Parasitología de Alimentos/métodos , Frutas/parasitología , Lactuca/parasitología , Toxoplasma/aislamiento & purificación , Brasil , Fragaria/parasitología , Oocistos/citología , Hojas de la Planta/parasitología , Reacción en Cadena de la Polimerasa
9.
Homeopathy ; 104(1): 48-56, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25576271

RESUMEN

UNLABELLED: This study evaluates the effect of Trypanosoma cruzi biotherapy 17dH (BIOT) on mice of different ages, infected with the protozoa concerned. METHOD: Performing a blind, controlled, randomized by drawing experiment, 110 animals four or eight-week-old, Swiss, male mice were divided into infected control treated hydroalcoholic 7% (CI-4 = 34 or CI-8 = 21 animals) and infected control treated with biotherapy 17dH-0.2 mL/animal/20 consecutive days/oral regimen (BIOT-4 = 33 or BIOT-8 = 21 animals). Animals were inoculated intraperitoneally with 1400 trypomastigote, T. cruzi Y-strain. Parasitological, immunological and histopathologic parameters were evaluated statistically, using Statistica-8.0 and R 3.0.2 program to analysis of survival. The study was approved by the Ethics Committee for Animal Experimentation/UEM. RESULTS: Four-week-old mice showed no statistical difference in parasitemia (P = 0.5718) between the treated and control group. Eight-week-old mice from the treated group had a higher parasite peak (P = 0.0424) and higher parasitemia (P < 0.005) than the control. To both groups of 4 and 8 weeks of age, treated or untreated, survival of mice was higher in the treated group than in the control, although it was not statistically significant (p-value = 0.32, 0.55 respectively). Four-week-old mice displayed a spleen section with a number of amastigote nests significantly higher in BIOT-4 than CI-4 (P = 0.01). In eight-week-old mice the number of amastigote nests (P < 0.001) and inflammatory foci (P < 0.06-10% significance) in the liver section were smaller in BIOT-8 than CI-8. Spleen giant cells were significantly higher in CI-8 than in BIOT-8 (P < 0.01). Eight-week-old animals treated with biotherapy showed higher parasitemia and lower tissue parasitism. Opposite pattern was observed in four-week-old animals. CONCLUSION: There is a difference of high diluted medication effect in four and eight-week-old mice. In the group of animals 8 weeks the immunomodulatory effect seems to have been higher. Hence, treatment with the medicine produced from T. cruzi modulates the inflammatory response with increased apoptosis and decreased serum levels of TGF-ß.


Asunto(s)
Terapia Biológica/métodos , Enfermedad de Chagas/terapia , Homeopatía , Animales , Enfermedad de Chagas/inmunología , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/patología , Inflamación/terapia , Hígado/patología , Masculino , Ratones , Factor de Crecimiento Transformador beta/sangre , Trypanosoma cruzi
10.
Dig Dis Sci ; 59(2): 307-14, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24185679

RESUMEN

BACKGROUND: Trypanosoma cruzi causes neuronal myenteric depopulation compromising intestinal function. AIM: The purpose of this study was to evaluate the influence of moderate physical exercise on NADH diaphorase (NADH-d)-positive neurons in the myenteric plexus and intestinal wall of the colon in mice infected with T. cruzi. MATERIALS AND METHODS: Forty 30-day-old male Swiss mice were divided into the following groups: trained infected (TI), sedentary infected (SI), trained control (TC), and sedentary control. The TC and TI groups were subjected to a moderate physical exercise program on a treadmill for 8 weeks. Three days after finishing physical exercise, the TI and SI groups were intraperitoneally inoculated with 1,300 blood trypomastigotes of the Y strain of Trypanosoma cruzi. Parasitemia was evaluated from days 4 to 61 after inoculation. On day 75 of infection, myenteric neurons in the colon were quantified (NADH-d), and inflammatory foci were counted. Tumor necrosis factor-α (TNF-α) and transforming growth factor-ß (TGF-ß) levels were evaluated in plasma. The results were compared using analysis of variance and the Kruskal-Wallis test at a 5 % significance level. RESULTS: Moderate physical exercise reduced the parasite peak on day 8 of infection (p = 0.0132) and total parasitemia (p = 0.0307). It also prevented neuronal depopulation (p < 0.01), caused hypertrophy of these cells (p < 0.05), prevented the formation of inflammatory foci (p < 0.01), and increased the synthesis of TNF-α (p < 0.01) and TGF-ß (p > 0.05). CONCLUSION: These results reinforce the therapeutic benefits of moderate physical exercise for T. cruzi infection.


Asunto(s)
Enfermedad de Chagas/terapia , Colon/inervación , Plexo Mientérico/parasitología , Neuronas/parasitología , Esfuerzo Físico , Trypanosoma cruzi/patogenicidad , Animales , Enfermedad de Chagas/sangre , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/patología , Dihidrolipoamida Deshidrogenasa/metabolismo , Modelos Animales de Enfermedad , Hipertrofia , Mediadores de Inflamación/sangre , Masculino , Ratones , Plexo Mientérico/metabolismo , Plexo Mientérico/patología , Neuronas/metabolismo , Neuronas/patología , Factores de Tiempo , Factor de Crecimiento Transformador beta/sangre , Factor de Necrosis Tumoral alfa/sangre
11.
Exp Parasitol ; 146: 34-42, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25296157

RESUMEN

The geographical heterogeneity of Chagas disease (ChD) is mainly caused by genetic variability of the etiological agent Trypanosoma cruzi. Our hypothesis was that the pathogenicity for mice may vary with the genetic lineage (or Discrete Typing Unit - DTU) of the parasite. To test this hypothesis, parasitological and histopathological evaluations were performed in mice inoculated with strains belonging to the DTU T. cruzi IV (TcIV) from the State of Amazonas (northern Brazil), or the DTU T. cruzi II (TcII) from the State of Paraná (southern Brazil). Groups of 10 Swiss mice were inoculated with eight strains of TcIV obtained from acute cases (7) from two outbreaks of orally acquired ChD, and from the triatomine Rhodnius robustus (1) from Amazonas; and three strains of TcII obtained from chronic patients in Paraná. We evaluated the pre-patent period, patent period, maximum peak of parasitemia, day of maximum peak of parasitemia, area under the parasitemia curve, inflammatory process, and tissue parasitism in the acute phase. TcIV was less virulent than TcII, and showed significantly (p < 0.005) lower parasitemia levels. Although the levels of tissue parasitism did not differ statistically, mice infected with TcIV displayed significantly (p < 0.001) fewer inflammatory processes than mice infected with TcII. This supported the working hypothesis, since TcIV from Amazonas was less pathogenic than TcII from Paraná; and agreed with the lower severity of human cases of ChD in the Amazon region.


Asunto(s)
Enfermedad de Chagas/parasitología , Trypanosoma cruzi/patogenicidad , Animales , Encéfalo/parasitología , Encéfalo/patología , Brasil/epidemiología , Enfermedad de Chagas/epidemiología , Enfermedad de Chagas/patología , Corazón/parasitología , Miembro Posterior , Hígado/parasitología , Hígado/patología , Masculino , Ratones , Músculo Esquelético/parasitología , Músculo Esquelético/patología , Miocardio/patología , Parasitemia/epidemiología , Parasitemia/parasitología , Parasitemia/patología , Bazo/parasitología , Bazo/patología , Trypanosoma cruzi/clasificación
12.
Int J Environ Health Res ; 24(5): 450-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24256564

RESUMEN

In this study, the prevalence and risk factors for enteroparasites were determined in food handlers from Maringá, Paraná State, southern Brazil. Fecal and subungual materials of 150 street food vendors were analyzed by the methods of Lutz, Faust, and Mello, respectively. A questionnaire on hygiene and sanitary conditions of the workplace and of domicile was applied. The prevalence of enteroparasites was 28%, and the protozoa infection was more expressive (21.3%) than by helminths (6.7%), but without significant difference (p > 0.05). Entamoeba coli was the most frequent species occurring in 15.3%, while the prevalence of protozoa pathogenic was low (Giardia lamblia: 2.7% and Entamoeba histolytica: 0.7%). The subungual material presented negative results. The presence of pets in domiciles has increased twice the risk of infection. The working conditions of the majority of street food vendors were inappropriate. The results highlight the need for more rigorous programs of continuing education, parasitological examination every six months, and health surveillance. In this way, the quality of the service provided to the population can be improved and the transmission of food-borne diseases can be prevented.


Asunto(s)
Manipulación de Alimentos , Enfermedades Transmitidas por los Alimentos/epidemiología , Parasitosis Intestinales/epidemiología , Exposición Profesional , Adulto , Anciano , Brasil/epidemiología , Femenino , Enfermedades Transmitidas por los Alimentos/parasitología , Humanos , Parasitosis Intestinales/parasitología , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Adulto Joven
13.
Exp Parasitol ; 135(3): 511-7, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23994765

RESUMEN

Oral infection has become the most important transmission mechanism of Chagas disease in Brazil. For this study, the development of Trypanosoma cruzi infection in mice, induced by the oral and intraperitoneal (IP) routes, was compared. Four groups of Swiss mice were used to evaluate the influence of parasite genetics, number of parasites, inoculation volume and developmental stages on the development of the orally induced infection: 1 - blood trypomastigotes (BT) via oral; 2 - BT via IP; 3 - culture metacyclic trypomastigotes (MT) via oral; and 4 - culture MT via IP. Animals inoculated orally showed levels of parasitemia, as well as infectivity and mortality rates, lower than animals inoculated via IP, regardless of DTU (discrete typing unit) and inoculum. Animals infected with TcII showed higher levels of these parameters than did animals infected with TcI. The larger volume of inoculum showed a greater capacity to cause an infection when administered via the oral route. BT infection was more virulent than culture MT infection for both routes (oral and IP). However, mice inoculated orally with BT showed lower levels than via IP, while mice inoculated orally with culture MT showed similar levels of infection to those inoculated via IP. Mice inoculated with culture MT showed more histopathological changes than those inoculated with BT, regardless of the inoculation route. These results indicate that this alternative experimental model is useful for evaluating infection by T. cruzi isolates with subpatent parasitemia and low virulence, such as those belonging to the TcI and TcIV DTUs, which are prevalent in outbreaks of orally transmitted Chagas disease.


Asunto(s)
Enfermedad de Chagas/parasitología , Trypanosoma cruzi/clasificación , Administración Oral , Animales , Enfermedad de Chagas/patología , Enfermedad de Chagas/transmisión , Contaminación de Alimentos , Parasitología de Alimentos , Masculino , Ratones , Cavidad Peritoneal/parasitología , Trypanosoma cruzi/crecimiento & desarrollo , Trypanosoma cruzi/patogenicidad , Virulencia
14.
Exp Parasitol ; 130(4): 321-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22406038

RESUMEN

The biological behaviour of 23 Trypanosoma cruzi isolates in Swiss mice was compared. Nineteen isolates were obtained from patients in the acute phase of Chagas disease (13), sylvatic reservoir hosts (Didelphis marsupialis) (3), and triatomine bugs (Rhodnius robustus) (3) from four regions of the State of Amazonas (AM). Four isolates were obtained from chronic chagasic patients in the State of Paraná (PR): three autochthones, and one allochthone from the State of Minas Gerais. Only one isolate was unable to infect the mice. The AM and PR isolates showed the largest number of significant differences from each other. The former had lower mean values in the pre-patent (5.4 days) and patent (4.6 days) periods (PP), with the parasitaemia (Pmax) reaching a peak of 9.9×10(4) blood trypomastigotes (BT)/mL of blood by the 7th day following inoculation. The AM isolates also had higher positivity to fresh-blood examination (FBE) (84.1%) compared to haemoculture (HC) (58.7%) and polymerase chain reaction (PCR) (33.3%), in addition to higher mortality (2.9%). The PR isolates had higher values for PP (18.5 days) and Pmax (99.9×10(4)BT/mL) as well as higher positivity to FBE (87.2%), HC (100%), and PCR (83.3%). The correlations between the biological behaviour of the T. cruzi isolates and the clinical and epidemiological characteristics of Chagas disease are discussed.


Asunto(s)
Enfermedad de Chagas/parasitología , Trypanosoma cruzi/fisiología , Animales , Brasil , Enfermedad de Chagas/mortalidad , Didelphis , Humanos , Masculino , Ratones , Parasitemia/parasitología , Rhodnius , Trypanosoma cruzi/patogenicidad , Virulencia
15.
Parasitol Int ; 86: 102484, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34688884

RESUMEN

In this study, a combination therapy of several natural products was evaluated in vivo in the Giardia duodenalis infection model. G. duodenalis infected mice were treated as follows: distilled water (infected control C+), BIOintestil® (BIO; natural products of Cymbopogon martinii and Zingiber officinale), MicrobiomeX® (MBX; extract of Citrus sinensis and Citrus paradisi), MBX + BIO, Camellia sinensis tea (CPR; black tea). These natural compounds were administered in a dose of 100 mg/day and were compared to G. duodenalis-infected mice treated with albendazole (ALB; 50 mg/Kg/day) and metronidazole (MET; 500 mg/Kg/day), the conventional therapies used to this day. One group remained un-infected and untreated as our control group (C-). Treatment started 8 days after infection, and after 5 days of treatment (7 days for MET), all animals were followed for 15 days. We continuously checked for the presence of G. duodenalis by Faust method, in association with detection of the parasite by PCR from feces, as well for the presence of trophozoites in the intestinal mucosa after sacrifice. Animals treated with MBX, BIO and MBX + BIO presented an undetectable parasitic load until the 15th day of monitoring, while animals treated with CPR, MET and ALB continued to release cysts. Animals in the MBX, MBX + BIO, ALB groups consumed lower feed, MBX, CPR, MET had greater weight and MBX, MBX + BIO, BIO, CPR, C- consumed more water when compared to infected-group control. MBX and BIO alone or associated eliminated G. duodenalis without apparent adverse effects and animals of these groups showed better clinical performance in relation to those with high parasitic load. MET, ALB and CPR only decreased the number of cysts, indicating limitations and therapeutic failure.


Asunto(s)
Antiparasitarios/farmacología , Giardia lamblia/efectos de los fármacos , Giardiasis/tratamiento farmacológico , Microbiota , Extractos Vegetales/farmacología , Albendazol/química , Albendazol/farmacología , Animales , Antiparasitarios/química , Citrus/química , Suplementos Dietéticos/análisis , Masculino , Metronidazol/química , Metronidazol/farmacología , Ratones , Extractos Vegetales/química , Distribución Aleatoria , Té/química
16.
Homeopathy ; 100(4): 237-43, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21962198

RESUMEN

OBJECTIVE: To evaluate the effects of different forms of administration of the blood trypomastigotes biotherapy 7dH in mice experimentally infected with Trypanosoma cruzi. MATERIAL AND METHODS: Male swiss mice were inoculated with 1400 blood trypomastigotes of the Y strain of T. cruzi and allocated into 5 treatment groups: IC (distilled water); TCBZ (benznidazole); TBA(7dH) (biotherapy 7dH 20 days after infection); TBB(7dH)7 (biotherapy 7dH seven days before infection); TBB(7dH)30 (biotherapy 7dH 30 days before infection). Parasitological parameters assessed included pre-patent and patent periods, parasitemia peak, total parasitemia, mortality and survival rates. Cure index was obtained by fresh blood examination, hemoculture and polymerase chain reaction (PCR). RESULTS: The TBB(7dH)7 group showed a reduction in parasitemia peak, parasitemia area under the curve and total parasitemia. TBB(7dH)30 showed a tendency to increased pre-patent and survival periods, peak parasitemia was increased without increased total parasitemia. TBA(7dH) did not present significant alterations in the parasitological parameters analyzed. CONCLUSIONS: Biotherapy 7dH given before infection (7 or 30 days) produces different effects suggesting modulation of the host's immune system. The effects range from reduced parasitemia to its effective increase. The use of biotherapy to treat T. cruzi infection including dose, potency and schedule deserves further investigation.


Asunto(s)
Enfermedad de Chagas/tratamiento farmacológico , Homeopatía , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Enfermedad de Chagas/parasitología , Modelos Animales de Enfermedad , Masculino , Ratones , Nitroimidazoles/farmacología
17.
Acta Parasitol ; 66(4): 1561-1564, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33893607

RESUMEN

PURPOSE: Our goal was to analyze the outcome of infection and response to benznidazole (BZ) treatment in mice intragastrically inoculated with trypomastigotes forms of Trypanosoma cruzi from different origins. METHODS: Twenty-four Swiss mice were divided in two groups and inoculated, by gavage, with 1 × 104 blood trypomastigotes (BT) or insect-derived metacyclic trypomastigotes (IT) of AM14 strain (T. cruzi IV). Half of the animals of each group were treated with BZ (TBZ), from 10 to 30th days after the inoculation, and the other constituted the untreated control groups (NT). After the etiological treatment, all mice were immunosuppressed with cyclophosphamide for three weeks. Parasitological and molecular parameters, infectivity, cumulative mortality, and reactivation post-immunosuppression rates were obtained. RESULTS: Animals inoculated with BT showed lower pre-patent period and early day of the maximum parasitemia, as well as a higher maximum peak of parasitemia than the IT animals. However, both, BT and IT animals, did not respond to BZ treatment (0.0% of cure). CONCLUSION: We conclude that the infective form influences in the outcome of infection, but not the response to the etiological treatment in mice intragastrically infected with the T. cruzi IV strain studied.


Asunto(s)
Enfermedad de Chagas , Trypanosoma cruzi , Animales , Enfermedad de Chagas/tratamiento farmacológico , Insectos , Ratones , Parasitemia/tratamiento farmacológico
18.
Exp Parasitol ; 126(4): 435-40, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20433834

RESUMEN

The goals of this study were to evaluate the effect of the Canova medication, a homeopathic immune-system modulator, on the evolution of infection induced by the Trypanosoma cruzi Y strain in mice. The animals were divided into five groups: (i) untreated infected controls (I), (ii) infected animals treated with benznidazole (Bz), (iii) infected animals treated with the Canova medication (CM), (iv) infected animals treated with benznidazole and the Canova medication (Bz+CM), and (v) uninfected controls that received only the vehicle (grain alcohol) (C). The parameters evaluated were: parasitemia, mortality, control of cure, and tissue parasitism analysis. Our results showed that the evolution of the experimental infection was modified by treatment with CM, and that daily and consecutive doses were harmful to the animals, causing death in 100% of the infected animals in a brief period. The analysis of parasitism performed on the organs on the 12th day postinfection showed that in infected animals treated with CM, the number of amastigote/nests in the spleen was significantly reduced, while in cardiac tissue, intestine, and liver the number was significantly increased compared with infected control animals. These results indicate that CM has a negative influence on the host-parasite relationship, modifying the tropism of the parasite for tissues, and increasing the parasitemia peak in this experimental model.


Asunto(s)
Enfermedad de Chagas/tratamiento farmacológico , Venenos de Crotálidos/uso terapéutico , Formularios Homeopáticos como Asunto , Extractos Vegetales/uso terapéutico , Trypanosoma cruzi/efectos de los fármacos , Animales , Enfermedad de Chagas/parasitología , Venenos de Crotálidos/farmacología , Quimioterapia Combinada , Corazón/parasitología , Interacciones Huésped-Patógeno/efectos de los fármacos , Intestinos/parasitología , Hígado/parasitología , Masculino , Ratones , Nitroimidazoles/farmacología , Nitroimidazoles/uso terapéutico , Parasitemia/tratamiento farmacológico , Parasitemia/parasitología , Extractos Vegetales/farmacología , Bazo/parasitología , Tripanocidas/farmacología , Tripanocidas/uso terapéutico , Trypanosoma cruzi/crecimiento & desarrollo , Trypanosoma cruzi/fisiología
19.
Arq Gastroenterol ; 57(2): 161-166, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32609158

RESUMEN

BACKGROUND: Intestinal constipation (IC) in patients with the digestive form of Chagas disease is one of the main reasons for seeking medical care. Population data indicate that the practice of physical activity improves gastrointestinal motility. OBJECTIVE: This study evaluated the bowel frequency and symptoms of constipation and their relationship with the level of physical activity in patients with and without Chagas disease. METHODS: Patients (n=120) of both genres, aged between 35 and 84 years, in which 50% (n=60) were in the Chagas group and 50% (n=60) were in the control group, were evaluated regarding the level of IC using the Constipation Assessment Scale (CAS) and regarding the level of physical activity using the International Physical Activity Questionnaire (IPAQ). RESULTS: - Patients in the Chagas group classified as active (IPAQ 2) had higher proportion (P=0.0235) of moderate IC with severe abdominal distension (P=0.0159) and decreased evacuation frequency (P=0.0281) than the patients in the control group, considered to be very active (IPAQ 1). The sedentary lifestyle was greater (P=0.0051) in the Chagas group with duration, intensity and frequency of physical activity lower than the control group. The health perception in the Chagas group was regular for 46.7% (P=0.0035) and poor for 8.3% (P=0.0244). CONCLUSION: There is a lower risk of developing intestinal constipation in more active individuals, evidencing that the level of physical activity interferes with bowel frequency and symptoms of constipation in patients with and without Chagas disease. The level of physical activity and health perception were worse in the Chagas group, reinforcing the disease stigma, which should be modified by the training of health professionals who routinely attend these patients.


Asunto(s)
Enfermedad de Chagas , Estreñimiento , Ejercicio Físico , Motilidad Gastrointestinal , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Intestinos , Persona de Mediana Edad
20.
Vector Borne Zoonotic Dis ; 19(11): 828-834, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31241422

RESUMEN

Trypanosoma cruzi is a parasitic protozoan that infects a diversity of hosts constituting the cycle of enzootic transmission in wild environments and causing disease in humans (Chagas disease) and domestic animals. Wild mammals constitute natural reservoirs of this parasite, which is transmitted by hematophagous kissing bugs of the family Reduviidae. T. cruzi is genetically subdivided into six discrete typing units (DTUs), T. cruzi (Tc)I to TcVI. In Brazil, especially in the state of Paraná, TcI and TcII are widely distributed. However, TcII is less frequently found in wild reservoirs and triatomine, and more frequently found in patients. The goal of this study was to investigate the natural occurrence of T. cruzi in wild synanthropic mammals captured in urban forest fragments of the Atlantic Forest of Paraná, southern Brazil. In this way, 12 opossums and 35 bats belonging to five species were captured in urban forest parks of the city of Maringá, Paraná, an area considered endemic for Chagas disease. PCR-kinetoplast DNA molecular diagnostic reveals Trypanosoma sp. infection in 12 (100%) Didelphis albiventris and 10 (40%) Artibeus lituratus. In addition to demonstrating the presence of Trypanosoma in the two groups of mammals studied, we obtained an isolate of the parasite genotyped as TcII by amplification of the cytochrome oxidase II gene by PCR, followed by restriction fragment length polymorphism with AluI, and confirmed by PCR of rDNA 24Sα. This is the first record of the encounter in wild mammals of Trypanosoma DNA (in A. lituratus) and T. cruzi DTU TcII (in D. albiventris) in the state of Paraná.


Asunto(s)
Quirópteros/parasitología , Didelphis/parasitología , Trypanosoma cruzi/aislamiento & purificación , Animales , Brasil/epidemiología , ADN Protozoario , Bosques , Genotipo , Reacción en Cadena de la Polimerasa , Trypanosoma cruzi/genética
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