RESUMO
Human toxocariasis is a parasitic anthropozoonosis that is difficult to treat and control. A previous study carried out with Lactobacillus acidophilus ATCC 4356 revealed that the cell free supernatant (CFS) of this probiotic killed 100% of Toxocara canis larvae in vitro. The present study aimed to investigate the characteristics of the CFS of L. acidophilus ATCC 4356, which may be involved in its larvicidal effects on T. canis. L. acidophilus ATCC 4356 was cultured, and lactic and acetic acids present in the CFS were quantified by high performance liquid chromatography (HPLC). The levels of pH and H2O2 were also analyzed. To assess the larvicidal effect of the CFS, this was tested pure and diluted (1:2 to 1:128) on T. canis larvae. High concentrations of lactic and acetic acids were detected in the CFS. The acidity of the pure CFS was observed at pH 3.8, remaining acidic at dilutions of 1:2 to 1:16. Regarding the in vitro larvicidal effect, 100% death of T. canis larvae was observed using the pure CFS and 1:2 dilution. Based on these results, it can be inferred that the presence of higher concentrations of organic acids and low pH of the medium contributed to the larvicidal activity of the CFS of L. acidophilus ATCC 4356. In addition, the maintenance of the larvicidal effect, even after dilution, suggests a greater chance of the larvicidal effect of this CFS against T. canis in vivo.
Assuntos
Probióticos , Toxocara canis , Toxocaríase , Animais , Humanos , Lactobacillus acidophilus/metabolismo , Peróxido de Hidrogênio/farmacologia , Toxocaríase/parasitologia , Larva , Acetatos/metabolismo , Acetatos/farmacologiaRESUMO
Human toxocariasis is a neglected anthropozoonosis with global distribution. Treatment is based on the administration of anthelmintics; however, their effectiveness at the tissue level is low to moderate, necessitating the discovery of new drug candidates. Several groups of synthetic compounds, including coumarin derivatives, have demonstrated bioactivity against fungi, bacteria, and even parasites, such as Dactylogyrus intermedius, Leishmania major, and Plasmodium falciparum. The aim of this study was to evaluate the effect of ten coumarin-derived compounds against Toxocara canis larvae using in vitro, cytotoxicity, and in silico tests for selecting new drug candidates for preclinical tests aimed at evaluating the treatment of visceral toxocariasis. The compounds were tested in vitro in duplicate at a concentration of 1 mg/mL, and compounds with larvicidal activity were serially diluted to obtain concentrations of 0.5 mg/mL; 0.25 mg/mL; 0.125 mg/mL; and 0.05 mg/mL. The tests were performed in a microculture plate containing 100 T. canis larvae in RPMI-1640 medium. One compound (COU 9) was selected for cytotoxicity analysis using J774.A1 murine macrophages and it was found to be non-cytotoxic at any concentration tested. The in silico analysis was performed using computational models; the compound presented adequate results of oral bioavailability. To confirm the non-viability of the larvae, the contents of the microplate wells of COU 9 were inoculated intraperitoneally (IP) into female Swiss mice at 7-8 weeks of age. This confirmed the larvicidal activity of this compound. These results show that COU 9 exhibited larvicidal activity against T. canis larvae, which, after exposure to the compound, were non-viable, and that COU 9 inhibited infection in a murine model. In addition, COU 9 did not exhibit cytotoxicity and presented adequate bioavailability in silico, similar to albendazole, an anthelmintic, which is the first choice for treatment of human toxocariasis, supporting the potential for future investigations and preclinical tests on COU 9.
Assuntos
Cumarínicos , Larva , Toxocara canis , Animais , Larva/efeitos dos fármacos , Toxocara canis/efeitos dos fármacos , Cumarínicos/farmacologia , Cumarínicos/química , Anti-Helmínticos/farmacologia , Anti-Helmínticos/química , Disponibilidade Biológica , Camundongos , Simulação por Computador , Toxocaríase/tratamento farmacológico , Toxocaríase/parasitologiaRESUMO
Probiotics have shown promising results as a potential method to control toxocariasis in mice inoculated with embryonated eggs of Toxocara canis. This study aimed to evaluate the protective effect of Saccharomyces boulardii in mice fed in natura chicken livers infected with T. canis. Twenty 15-day-old male Sussex chickens were inoculated with 300 T. canis embryonated eggs via intragastric catheter (GI). After 72 h of infection, each liver was collected and individually offered to a group of 20 mice. Mice that received supplemented ration with S. boulardii (1.107 colony forming units) and consumed in natura chicken liver showed reduction in infection intensity of 67.1%. This study demonstrated that administration of S. boulardii has potential as a probiotic to assist in controlling visceral toxocariasis caused by the consumption of viscera from paratenic hosts containing infective parasite larvae.
Assuntos
Probióticos , Saccharomyces boulardii/fisiologia , Toxocaríase/microbiologia , Toxocaríase/parasitologia , Animais , Galinhas/microbiologia , Galinhas/parasitologia , Larva/efeitos dos fármacos , Fígado/parasitologia , Masculino , Camundongos , Toxocara canis/fisiologiaRESUMO
AIM: While the use of recombinant antigens is being widely investigated in the diagnosis of human toxocariasis, relatively little attention has been given to animal diagnostic models. For this reason, this study aimed to investigate the diagnosis potential of Toxocara canis TES-30 and TES-120 recombinant antigens in mice, the animal model for toxocariasis studies. METHODS AND RESULTS: Serum samples obtained from mice infected with T. canis or Toxocara cati were tested by indirect ELISA using T. canis TES-30 and TES-120 recombinant antigens produced in Escherichia coli. 90% of the samples reacted with rTES-30, whereas there was almost no reactivity with rTES-120. CONCLUSION: Despite rTES-120 being a good antigen for diagnosis in humans, it could not reproduce its reactivity in this animal model. As rTES-30 has good reactivity in mice, it is a valuable tool for diagnosis.
Assuntos
Antígenos de Helmintos/imunologia , Proteínas de Helminto/imunologia , Toxocara canis/imunologia , Toxocaríase/parasitologia , Animais , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Humanos , Camundongos , Proteínas Recombinantes , Toxocaríase/imunologiaRESUMO
Human toxocariasis is a neglected global parasitic zoonosis. The efficacy of drug treatment for this disease has been hindered by the biological complexity of the main etiological agent, the nematode Toxocara canis. Experimental studies have shown the potential of probiotics to promote a reduction in the parasite load of T. canis larvae. This study aimed to evaluate the effect of probiotic Lactobacillus rhamnosus ATCC 7469 on the parasite load of BALB/c mice with acute toxocariasis and evaluate the direct effect of this probiotic on T. canis larvae in vitro. In vivo administration of probiotics reduced the parasite load of T. canis larvae by 53.3% (p = 0.0018) during the early stage of infection in mice. However, when analyzed in vitro, it was observed that the probiotic did not present a deleterious effect on the larvae, as approximately 90% of these remained viable. These results demonstrate the potential of the probiotic L. rhamnosus in the reduction of T. canis larvae in BALB/c mice and suggest it could be used as an alternative means for the controlling of visceral toxocariasis. However, further studies are required to elucidate the mechanisms of action promoted by this probiotic.
Assuntos
Lacticaseibacillus rhamnosus/fisiologia , Probióticos/administração & dosagem , Toxocara canis/efeitos dos fármacos , Toxocaríase/tratamento farmacológico , Animais , Humanos , Larva/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Carga Parasitária , Toxocara canis/microbiologia , Toxocara canis/fisiologia , Toxocaríase/parasitologia , Zoonoses/tratamento farmacológico , Zoonoses/parasitologiaRESUMO
Considering the therapeutic potential of fatty acid amides, the present study aimed to evaluate their in vitro activity against Toxocara canis larvae and their cytotoxicity for the first time. Linoleylpyrrolidilamide was the most potent, with a minimal larvicidal concentration (MLC) of 0.05 mg/mL and 27% cytotoxicity against murine peritoneal macrophages C57BL/6 mice, as assessed by the MTT assay.
Assuntos
Amidas/química , Amidas/farmacologia , Antiprotozoários/química , Antiprotozoários/farmacologia , Ácidos Graxos/química , Toxocara canis/efeitos dos fármacos , Animais , Larva/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Toxocara canis/crescimento & desenvolvimentoRESUMO
OBJECTIVE: The objective of this study is to investigate the association between anti-Toxocara IgG seropositivity and asthma in children. METHODS: This was a case-control study conducted in a university hospital in south Brazil between May 2012 and June 2013. Were recruited 208 children up to 12 years old of whom 156 had asthma (cases) and 52 did not have asthma (controls), with a case-control ratio of 3:1 matched by age. Children's parents or guardians were interviewed using a structured questionnaire with closed questions. Serology was performed using enzyme-linked immunosorbent assay (ELISA) with excretory-secretory antigen of Toxocara canis (TES). RESULTS: The seroprevalence of IgG anti-T. canis antibodies was 12.8% in the cases and 7.7% in the controls. There was no significant association between seropositivity to T. canis and risk of asthma (adjusted odds ratio [OR]: 1.89, 95% CI: 0.52 to 6.89, p = 0.33). Household income < 2 minimum salaries, paternal school years < 9, allergic rhinitis in children, a positive family history of asthma and rhinitis and contact with cats were significantly associated with asthma, with adjusted ORs (95% CIs) of 3.05 (1.21 to 7.73), 2.83 (1.11 to 7.18), 10.5 (4.32 to 25.6), 2.65 (1.14 to 6.17), 2.49 (1.07 to 5.78) and 2.73 (1.03 to 7.27), respectively. CONCLUSIONS: This study did not find a statistically significant association between seropositivity to Toxocara sp. and risk of asthma in children. Low family income, low paternal education level, concomitant allergic rhinitis, family history of asthma and allergic rhinitis and contact with cats were independent factors associated with childhood asthma.
Assuntos
Asma/epidemiologia , Imunoglobulina G/sangue , Toxocara/imunologia , Toxocaríase/epidemiologia , Toxocaríase/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Brasil/epidemiologia , Estudos de Casos e Controles , Gatos , Criança , Pré-Escolar , Cães , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lactente , Masculino , Rinite Alérgica/epidemiologia , Fatores de Risco , Estudos Soroepidemiológicos , Fatores Socioeconômicos , Toxocaríase/transmissãoRESUMO
Human toxocariasis is a neglected parasitic zoonosis of worldwide distribution. The consumption of raw or undercooked meat and offal from paratenic hosts of the Toxocara canis nematode can cause infection in humans, but there have been a lack of studies examining specific prophylactic measures to combat this mode of transmission. The aim of this study was to evaluate the establishment of infection by T. canis larvae at the initial and chronic phases of visceral toxocariasis after the consumption of mouse liver subjected to cold treatment. This study was divided into two stages using groups (G) of five donor mice inoculated with 2,000 eggs of T. canis. Two days post-inoculation, the livers of donor mice in G1 and G2 were kept at -20 °C and between 0 and 4 °C, respectively, for 10 days. In the first stage of the study, the livers of mice from G1, G2, and G3 (control) were subjected to a tissue digestion technique and found to be positive for infection. In the second stage, which evaluated infection in mice that had consumed livers from donor mice, receiver mice of G4 and G7 were fed with livers of donor mice from G1 (freezing), receiver mice of G5 and G8 were fed with livers of donor mice from G2 (cooling), and receiver mice of G6 and G9 with livers from G3 (control). Then, the tissue digestion technique was performed for recovering larvae from organs and carcasses of mice, at 2 days (G4, G5, and G6) and 60 days after liver consumption (G7, G8, and G9). It was observed that freezing inhibited the viability of 100 % of the larvae, while cooling promoted 87.7 and 95.7 % reductions in the intensity of infection at 2 and 60 days after liver consumption, respectively. Under the studied conditions, cold treatment shows great potential to help control this parasitosis, both in the initial and chronic phases of toxocariasis.
Assuntos
Tecnologia de Alimentos/métodos , Doenças Transmitidas por Alimentos/prevenção & controle , Doenças Transmitidas por Alimentos/parasitologia , Fígado/parasitologia , Toxocara canis/efeitos da radiação , Toxocaríase/prevenção & controle , Toxocaríase/parasitologia , Estruturas Animais/parasitologia , Animais , Modelos Animais de Doenças , Doenças Transmitidas por Alimentos/patologia , Congelamento , Larva/efeitos da radiação , Camundongos , Refrigeração , Análise de Sobrevida , Toxocara canis/isolamento & purificação , Toxocaríase/patologiaRESUMO
Toxocariasis is an anthropozoonosis caused by the helminth Toxocara canis that shows different clinical manifestations as visceral, ocular, or neurological toxocariasis forms. Probiotics have been studied as alternatives to prevent and treat this parasitosis. Lactobacillus rhamnosus is a prospect that presents immunomodulatory activity that acts to strengthen the intestinal barrier. In this context, the main objective of this study was to evaluate the protective capacity and immunomodulatory action of the probiotic Lactobacillus rhamnosus at the level of the intestinal mucosa in different stages of T. canis infection (acute and chronic). Mice were supplemented by oral gavage with 1 × 107 UFC/mL L. rhamnosus for 15 days before inoculation with 100 embryonated eggs of T. canis. Euthanasia of mice was conducted at three different time points: 2, 15 and 30 days post-inoculation (PI). The brain, lungs and liver were collected to evaluate the intensity of infection. The small intestines were removed, and mucosal cells of the duodenum were collected to perform gene analysis of IFN-γ, IL-10, IL-4 and IL-13 by real-time polymerase chain reaction (qPCR). Jejunum and ileum segments were analysed by histological techniques. A reduction of 51% in infection intensity was observed in the tissue of supplemented animals evaluated 2 days PI; however, analysis of groups 15 and 30 days PI did not show a protective effect. The intestinal mucosa of supplemented animals presented an inflammatory process that initiated at 2 days PI, persisted at 15 days PI and had regressed at 30 days PI. IL-13 transcription was increased in the probiotic group 2 days after supplementation ended; however, the same increase was not observed in the group that was supplemented and infected. Toxocara canis modulated the local immune system, with suppression of IFN-γ at 2 days PI and increased levels of IL-4 and IL-10 at 15 days PI. These results indicate that, under the studied conditions, the protective effect of Lactobacillus rhamnosus against infection caused by T. canis is not related to IL-4, IL-10 or IFN-γ but could be influenced by IL-13 action at 2 days PI. The probiotic stimulated immune cell recruitment to the intestinal mucosa, which can be involved in the diminished capacity of larval penetration in the mucosa, resulting in the reduced infection intensity observed during acute infection.
Assuntos
Lacticaseibacillus rhamnosus , Probióticos , Toxocara canis , Toxocaríase , Animais , Camundongos , Toxocaríase/patologia , Interleucina-10 , Interleucina-4 , Interleucina-13 , Mucosa Intestinal/patologia , ImunomodulaçãoRESUMO
Visceral toxocariasis is a serious public health problem with a cosmopolitan distribution. Children are susceptible due to their immature immune system and high risks of infection. Nevertheless, the few completed studies about immunosuppression have had controversial results. To evaluate the effect of two immunosuppressive drugs on the larval burden of Toxocara canis, four groups of ten Swiss strain mice each were inoculated on day 0 with 1,200 embryonated T. canis eggs. Fifteen days before the experimental infection, group 1 (control) was treated via intraperitoneal injection (IP) with sterile distilled water and groups 2 and 3 were treated with dexamethasone (DEX) at 1 and 5 mg/kg/day, respectively. Additionally, group 4 was treated IP with cyclophosphamide (CY) at 50 mg/kg at two times per week for 2 weeks. Sixty days following infection, the mice were euthanised to recover the larvae by means of the tissue digestion technique. The levels of antibodies detected by indirect ELISA were not associated with the larval burden. Administration of CY (50 mg/kg) and DEX (5 mg/kg) resulted in an increase of the larval burden of 162.1% and 50.8%, respectively, in relation to the control group. These two treatments, especially CY (50 mg/kg), promoted immunosuppression and the establishment of a significant larval burden, supporting its further utilisation in studies related to immunosuppression in visceral toxocariasis.
Assuntos
Ciclofosfamida/administração & dosagem , Dexametasona/administração & dosagem , Imunossupressores/administração & dosagem , Toxocara canis/imunologia , Toxocara canis/patogenicidade , Toxocaríase/imunologia , Toxocaríase/parasitologia , Estruturas Animais/parasitologia , Animais , Feminino , Larva/imunologia , Larva/patogenicidade , Camundongos , Carga Parasitária , Toxocara canis/isolamento & purificaçãoRESUMO
Helicobacter pylori infects nearly 50% of the world's population. This microorganism is accepted as the most important agent of gastritis and as a risk factor for peptic ulcer disease and gastric adenocarcinoma. Currently many diagnostic methods exist for detecting H. pylori, however they all have limitations, thus it is recommend a combination of at least two methods. The aim of this study was to evaluate diagnostic methods, such as in-house urease test, culture and Polymerase Chain Reaction (PCR), for the detection of the H. pylori in gastric biopsy specimens of 144 dyspeptic patients, using as gold standard the association between histology and rapid urease test. According to the gold standard used in this study, 48 (33.3%) patients were infected with H. pylori, while 96 (66.7%) were classified as not infected. The in-house urease test and the PCR were the most sensitive methods (100%), followed by culture (85.4%). However, the inhouse urease test and the culture were the most specific (100%), followed by PCR (75%). In conclusion, this study showed that, in comparison with the combination of histology and rapid urease test, the in-house urease test and the PCR presented 100% of sensitivity in the diagnosis of gastric infection by H. pylori, while the in-house urease test and the culture reached 100% of specificity. These finding suggest that the combination of two or more methods may improve the accuracy of the H. pylori detection.
RESUMO
Human toxocariasis consists of chronic tissue parasitosis that is difficult to treat and control. This study aimed to evaluate the action of the probiotic Lactobacillus acidophilus ATCC 4356 on larvae of Toxocara canis and the effect of IFN-γ cytokine on parasite-host in vivo (1.109 CFU) and in vitro (1.106, 1.107, 1.108, 1.109 CFU) interactions. Four groups of six BALB/c mice were formed: G1 - L. acidophilus supplementation and T. canis infection; G2 - T. canis infection; G3 - L. acidophilus supplementation; and G4 - PBS administration. Mice were intragastrically suplemented with probiotics for 15 days before inoculation and 48 h after inoculation with 100 T. canis eggs. The inoculation of T. canis was also perfomed intragastrically. The recovery of larvae took place through digestion of liver and lung tissues; the evaluation of IFN-γ gene transcription in leukocytes was performed by qPCR. The in vitro test consisted of incubating the probiotic with T. canis larvae. The supplementation of probiotics produced a reduction of 57.7% (p = 0.025) in the intensity of infection of T. canis larvae in mice, whereas in the in vitro test, there was no larvicidal effect. In addition, a decrease in the IFN-γ gene transcription was observed in both, T. canis-infected and uninfected mice, regardless of whether or not they received supplementation. The probiotic L. acidophilus ATCC 4356 reduced T. canis infection intensity in mice, however, the probiotic did not have a direct effect on larvae, demonstrating the need of interaction with the host for the beneficial effect of the probiotic to occur. Yet, the proinflammatory cytokine IFN-γ did not apparently contributed to the observed beneficial effect of probiotics.
Assuntos
Lactobacillus acidophilus/efeitos dos fármacos , Probióticos/administração & dosagem , Toxocara canis/efeitos dos fármacos , Toxocaríase/tratamento farmacológico , Toxocaríase/prevenção & controle , Animais , Lactobacillus , Larva/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Probióticos/farmacologia , Toxocara canis/microbiologia , Toxocara canis/fisiologia , Toxocaríase/parasitologiaRESUMO
This study identified pathogenicity genes in 40 Helicobacter pylori clinical isolates. The cagA, vacA, and iceA genes were detected in 65%, 97.5%, and 97.5% of the isolates, respectively. The cagA, iceA1, and vacAs1a/m1 genes were related to erosive gastritis, whereas the vacAs2/m2 and iceA2 genes were associated with enanthematous gastritis.
Assuntos
Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/patogenicidade , Fatores de Virulência/genética , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Helicobacter pylori/isolamento & purificação , Humanos , Reação em Cadeia da PolimeraseRESUMO
The nematode Toxocara canis is of public health importance and is the main causative agent of toxocariasis in humans. This disease is difficult to diagnose due to several factors, including the possibility of cross-reactions with other nematodes in the ELISA. To overcome this problem, molecular tests have been recommended as an alternative to identify the parasite. The quantitative real-time polymerase chain reaction (qPCR) technique was used in this study to identify and quantify the parasite load of T. canis in the mouse brain. To this end, 24 mice were divided into six groups, five of which were challenged with different infective doses of T. canis larvae (L3) (1000, 500, 250, 100 and 50 larvae), while the sixth group, uninfected, acted as negative control. Forty-five days after infection, the animals were euthanized to collect the brain, from which two portions of 20 mg of tissue were taken for DNA extraction, while the rest of the brain tissue was digested to quantify the number of larvae by microscopy. The number of DNA copies was calculated from the standard DNA quantification curve, showing values of E = 93.4%, R2 = 0.9655 and Y = -3.415. A strong positive correlation (R = 0, 81; p < .001) was found between the number of copies and the recovery of larvae from brain. However, the parasite's DNA was also identified even in animals from whose brain no larvae were recovered after tissue digestion. The results of this study therefore confirm that the qPCR technique can be a valuable tool for the detection and quantification of T. canis DNA in murine hosts, even in animals whose with tissues contain very few parasites.
Assuntos
Encéfalo/parasitologia , DNA de Helmintos/análise , Olho/parasitologia , Carga Parasitária/métodos , Parasitologia/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Toxocara canis/isolamento & purificação , Animais , Feminino , Larva/crescimento & desenvolvimento , Camundongos , Carga Parasitária/instrumentação , Parasitologia/instrumentação , Toxocara canis/crescimento & desenvolvimentoRESUMO
Toxocariasis is a zoonotic disease that affects humans and animals alike. Although recombinant proteins are widely used for its diagnosis in humans, their performance in companion and production animals remains unknown. This study aimed to investigate the serodiagnostic potential of the recombinant proteins rTES-30 and rTES-120 from Toxocara canis in an indirect ELISA for cattle, horses, and sheep. Serum samples collected from the animals were tested with indirect ELISA and Western Blotting using T. canis TES-30 and TES-120 recombinant proteins produced in Escherichia coli, as well as native-TES. In the ELISA, rTES-30 showed high serodiagnostic potential in sheep and horses (92.6% and 85.2%, respectively), while the sensitivity of rTES-120 was higher in cattle and horses (97.2% and 92.6%, respectively). Furthermore, a highly positive association was observed between native and recombinant proteins in seropositive samples, while a moderately positive association was observed in seronegative samples, probably due to the lower specificity of native TES. In conclusion, our study indicates that the use of recombinant proteins in an indirect ELISA is an effective tool for the serodiagnosis of toxocariasis in animals, with the choice of protein being species-dependent.
Assuntos
Proteínas de Helminto/imunologia , Proteínas Recombinantes/imunologia , Testes Sorológicos/métodos , Toxocara canis/imunologia , Toxocaríase/diagnóstico , Animais , Bovinos , Feminino , Cavalos , Masculino , Ovinos , Toxocaríase/imunologia , Toxocaríase/parasitologiaRESUMO
Toxocariasis is a neglected zoonosis that affects children and adults. Recombinant proteins have been widely investigated for diagnosis, achieving high sensitivity and specificity in an overall population; however, little is known about age as a factor in its application. This study aims to investigate the diagnostic potential of Toxocara canis TES-30 and TES-120 recombinant proteins in humans, differentiating between its performance in children and adults. Serum samples collected from children and adults seropositive to Toxocara spp. were tested with indirect ELISA using T. canis TES-30 and TES-120 recombinant proteins produced in Escherichia coli. While rTES-30 sensitivity was not affected by age (81.8% in children and 87% in adults), rTES-120 sensitivity severely decreased in children to only 63.6%, down from 95.7% in adults. Furthermore, the sensitivity of rTES-30 increased to 97.8% after Western blotting confirmation. High specificity (>94%) against other geohelminths was reported for both recombinant proteins. Our study favors the use of rTES-30 with total IgG as the primary antibody in an indirect ELISA assay as a tool for epidemiological human studies.
Assuntos
Proteínas Recombinantes/metabolismo , Testes Sorológicos/métodos , Toxocara , Adulto , Animais , Criança , Pré-Escolar , Custos e Análise de Custo , Humanos , Lactente , Prognóstico , Sensibilidade e Especificidade , Testes Sorológicos/economia , Fatores de TempoRESUMO
The main etiological agent of toxocariasis is the helminth Toxocara canis. Several difficulties are found in the diagnosis of this disease, because of nonspecific clinical signs and possible cross-reactions that may occur in the available test, the indirect ELISA. Therefore, molecular diagnosis has been indicated as an alternative to conventional diagnosis. The purpose of this study was to evaluate the polymerase chain reaction (PCR) technique for the identification of T. canis in tissues of experimentally infected mice. To this end, nine mice were inoculated with 1500 embryonated eggs and were divided into two groups, the first euthanized 48â¯h (G1) and the other 30 days post inoculation (G2). Lungs, brain, liver and blood were collected from all the animals for DNA Extraction and tissue digestion, also was collected blood samples for DNA extraction and ELISA test (serum). Toxocara canis DNA was identified in all the inoculated animals using the ITS-2 target gene. The PCR test successfully identified the parasite in the brain, lung and liver of the animals euthanized 48â¯h PI and 30 days PI. This technique yielded good results in the identification of the parasite in the brain, being more sensitive than the method for the recovery of larvae, in the group with acute infection (48â¯h PI). The infection was confirmed by PCR within 48â¯h after infection, while the ELISA indicated serological conversion occurred only 14 days after inoculation. This study demonstrates the ability of PCR to identify T. canis in the liver, lungs and brain during acute and chronic infection.
Assuntos
DNA/isolamento & purificação , Larva/imunologia , Toxocara canis/genética , Toxocara canis/imunologia , Toxocaríase/diagnóstico , Toxocaríase/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , CamundongosRESUMO
Toxocariasis is a neglected and geographically widespread parasitic disease. The detection of specific antibodies associated with this disease is required to confirm its clinical diagnosis and to aid in prevention. Although helminth infection during pregnancy can promote foetal immune responses with long-term effects, specific information regarding the risk of Toxocara spp. infection to the human foetus during pregnancy is lacking. Therefore, the present study aimed to investigate the frequency of antibodies against Toxocara spp. in umbilical cord serum samples to determine the neonatal risk factors associated with Toxocara spp. infection. A cross-sectional study of the frequency of specific antibodies against Toxocara spp. was performed on umbilical cord samples of 280 neonates. A cord blood sample was obtained from each newborn after parturition, and serum samples were examined by enzyme-linked immunoassay. Epidemiological data were obtained through a questionnaire regarding obstetric history (abortion history, premature birthhistory, and pregnancy and birth numbers), general aspects (animal contact anddiet) and socio-economic factors. The frequency of anti-Toxocara spp. IgG antibodies in the umbilical cords of neonates was 20% in serum pre-adsorbed with Ascaris spp. antigen. Family income and dog ownership were considered risk factors associated with infection. No association was found between reproductive disorders and Toxocara seropositivity. The 20% frequency rate of anti-Toxocara spp. IgG antibodies in sera from umbilical cords of newborns can be related to IgG binding at the maternal-foetal interface, requiring greater care during pregnancy. Anti-Toxocara IgM and IgE antibodies no were found in umbilical cord serum samples, indicating that no vertical transmission of these parasites occurred in this population. Studies regarding antibodies against Toxocara spp. in umbilical cord sera are important for determining neonatal exposure to these parasites.
Assuntos
Anticorpos Anti-Helmínticos/sangue , Toxocara/imunologia , Toxocaríase/epidemiologia , Cordão Umbilical/imunologia , Animais , Anticorpos Anti-Idiotípicos/sangue , Ascaris/imunologia , Brasil/epidemiologia , Estudos Transversais , Cães , Feminino , Hospitais Universitários , Humanos , Recém-Nascido , Animais de Estimação , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos , Fatores SocioeconômicosRESUMO
BACKGROUND: Trichomoniasis is the most prevalent non-viral sexually transmitted disease (STD) in the world; however, it remains a neglected parasitic disease. This study aimed to determine the prevalence of trichomoniasis and its associated epidemiological factors among women treated at a hospital in southern Brazil. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional study was performed to determine the prevalence of this infection in women treated at Hospital Universitário (HU) in Rio Grande, Rio Grande do Sul, Brazil, between January 2012 and January 2015. This study consisted a self-administered questionnaire regarding demographic, clinical, and behavioural data and a molecular diagnosis with polymerase chain reaction (PCR) using the TVK3/7 primer set, which was confirmed with sequence analysis. Of the 345 women surveyed, the overall prevalence of Trichomonas vaginalis (T. vaginalis) was 4.1% (14/345). The prevalence rates were 5.9% among pregnant women, 8.5% among HIV-positive women, and 10.1% among HIV-positive pregnant women. The rates for groups with other significant demographic and clinical features were as follows: 6.6% among women with white skin, 12.3% among women with an income below the minimum monthly wage, 7.4% among women with a vaginal pH greater than or equal to 4.6, and 7.9% among women with a comorbid STD. The multivariate analysis confirmed that pregnant women who were HIV-positive (p = 0.001) and had low incomes (p = 0.026) were the most likely to have this infection. CONCLUSIONS: A multivariate analysis confirmed that HIV-positive pregnant women with low incomes were the participants most likely to have trichomoniasis. These results are important because this Brazilian region presents a high prevalence of HIV-1 subtype C, which is associated with greater transmissibility. Additionally, low family income reveals a socioeconomic fragility that might favour the transmission of this STD.
Assuntos
Infecções por HIV/epidemiologia , HIV-1/isolamento & purificação , Complicações Infecciosas na Gravidez/epidemiologia , Vaginite por Trichomonas/epidemiologia , Trichomonas vaginalis/isolamento & purificação , Adulto , Brasil/epidemiologia , Estudos Transversais , Feminino , Infecções por HIV/complicações , Infecções por HIV/diagnóstico , Hospitais Universitários , Humanos , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Prevalência , Fatores de Risco , Vaginite por Trichomonas/complicações , Vaginite por Trichomonas/diagnóstico , Adulto JovemRESUMO
Introduction Toxoplasmosis a parasitic zoonosis of global distribution, responsible for disorders during gestation can cause fetal death or congenital anomalies. Objective To evaluate the knowledge of toxoplasmosis among pregnant and postpartum women treated at the University Hospital of the city of Rio Grande, Rio Grande do Sul, Brazil. Methods This was a cross-sectional study of 100 pregnant and postpartum women at the University Hospital. Participants answered a self-administered questionnaire and gave consent for data relating to serological examinations to be abstracted from their medical records. Results The proportion of women who received information about toxoplasmosis was higher among those who received care in the private health care system (52.9%) than among those cared for in the public health care system (25.0%). Only 55.7% of women reported having some knowledge about toxoplasmosis. Of these, 53.7% received information during the prenatal period. However, most participants were unable to answer questions about preventive measures and modes of infection. Of the 100 patients in the study, only 46 underwent serologic testing for toxoplasmosis, 65.2% of whom tested negative (IgG). Conclusion Findings from this study are relevant to the training of health professionals regarding toxoplasmosis education and prevention. Improved education for health care providers and patients can lead to earlier diagnoses and reductions in adverse outcomes.