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BACKGROUND: Telomere length has been investigated as a biomarker of biological aging and is associated with several diseases, lifestyle, and socioeconomic factors. OBJECTIVE: This study aimed to verify whether food insecurity is associated with shorter telomere length in older people. METHODS: This is a cross-sectional study carried out in a municipality in the interior of Brazil, with a sample of 440 older people from the community. For telomere length analysis, a blood sample was obtained from each participant, followed by real-time qPCR, and sociodemographic and health information was collected through interviews. Food security/insecurity was measured using the reduced version of the Brazilian Food Insecurity Scale. Descriptive analysis and multiple logistic regression were performed to analyze the factors associated with shorter telomere length, adopting a significance level of 5%. RESULTS: We found that food insecurity was significantly associated with shorter telomere length, regardless of age group, skin color, tabagism, physical activity, milk and dairy consumption, living arrangement, and basic activities of daily life. CONCLUSION: The findings show the importance of ensuring full access to adequate nutrition for the older population, who are physiologically and socially vulnerable.
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This study investigates the efficacy of nebivolol (NBV) in experimental models of toxoplasmosis, focusing on parasite burden reduction and neuronal protection. In the acute model of experimental toxoplasmosis, Swiss mice infected with RH strain tachyzoites received oral NBV chlorhydrate doses of 2 mg/kg/day and 4 mg/kg/day for 8 days. Treatment with NBV significantly reduced parasite burden compared to vehicle and standard drug (PYR) groups. In the chronic model of experimental toxoplasmosis, C57/BL6 mice infected with the ME49 strain received NBV chlorhydrate 41 days post-infection and were evaluated after 10 days of treatment. NBV chlorhydrate effectively reduced cyst number and area, as well as bradyzoite burden compared to controls. Histological analysis demonstrated that NBV chlorhydrate preserved neuronal count, with the 4 mg/kg/day dose yielding counts similar to non-infected mice. Statistical analysis confirmed significant differences compared to control groups. Furthermore, immunohistochemical analysis revealed a significant reduction in iNOS labeling in the brains of mice treated with NBV chlorhydrate, indicating a decrease in nitric oxide production compared to control groups. These findings suggest NBV's potential as a promising candidate for toxoplasmosis treatment, highlighting its ability to reduce parasite burden and protect neuronal integrity. Further research is warranted to elucidate NBV's mechanisms of action and its clinical application in managing toxoplasmosis.
Assuntos
Encéfalo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Nebivolol , Carga Parasitária , Toxoplasmose Animal , Animais , Nebivolol/farmacologia , Nebivolol/uso terapêutico , Camundongos , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Animal/parasitologia , Encéfalo/parasitologia , Encéfalo/patologia , Encéfalo/efeitos dos fármacos , Feminino , Neurônios/efeitos dos fármacos , Neurônios/parasitologia , Etanolaminas/farmacologia , Etanolaminas/uso terapêutico , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Antiprotozoários/administração & dosagem , Benzopiranos/farmacologia , Benzopiranos/uso terapêutico , Resultado do Tratamento , Óxido Nítrico/metabolismo , Toxoplasma/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismoRESUMO
Toxoplasmosis is a globally prevalent zoonotic disease with significant clinical implications, including neurotoxoplasmosis, a leading cause of cerebral lesions in AIDS patients. The current pharmacological treatments for toxoplasmosis face clinical limitations, necessitating the urgent development of new therapeutics. Natural sources have yielded diverse bioactive compounds, serving as the foundation for clinically used derivatives. The exploration of marine bacteria-derived natural products has led to marinoquinolines, which feature a pyrroloquinoline core and demonstrate in vitro and in vivo anti-Plasmodium activity. This study investigates the in vitro anti-Toxoplasma gondii potential of six marinoquinoline derivatives. Additionally, it conducts absorption, distribution, metabolism, excretion, and toxicity (ADMET) predictions, and evaluates the in vivo efficacy of one selected compound. The compounds displayed half-maximal effective concentration (EC50) values between 1.31 and 3.78 µM and half-maximal cytotoxic concentration (CC50) values ranging from 4.16 to 30.51 µM, resulting in selectivity indices (SI) from 3.18 to 20.85. MQ-1 exhibiting the highest in vitro SI, significantly reduced tachyzoite numbers in the peritoneum of RH-infected Swiss mice when it was orally administered at 12.5 mg/kg/day for eight consecutive days. Also, MQ-1 significantly reduced the cerebral parasite burden in chronically ME49 infected C57BL/6 mice when it was orally administered at 25 mg/kg/day for 10 consecutive days. These findings underscore the promising anti-T. gondii activity of marinoquinolines and their potential as novel therapeutic agents against this disease.
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Toxoplasmosis is a significant public health concern with limited therapeutic options. The medicines for malaria venture (MMV) developed the pandemic response box (PRB) containing 400 drug-like molecules with broad pathogen activity. The aim of this work is to evaluate PRB compounds for their anti-Toxoplasma gondii activity and identify promising candidates for further evaluation. Screening identified 42 selective compounds with half effective concentration (EC50) ranging from 2.4 to 913.1 nm and half cytotoxic concentration (CC50) ranging from 6 µm to >50 µm. Selectivity index (SI) values (CC50/EC50) ranged from 11 to 17 708. Based on its in silico and in vitro profile and its commercial availability, RWJ-67657 was selected for further studies. Molecular docking analysis showed RWJ-67657 is predicted to bind to T. gondii p38 mitogen-activated protein kinase (TgMAPK). Oral administration of RWJ-67657 (20 mg kg day−1/10 days) significantly reduced parasite burden in chronically infected mice compared to mock-treated group (P < 0.01). These findings highlight the PRB as a promising source for anti-T. gondii compounds, with several showing favourable drug properties, including MMV1634492, MMV002731, MMV1634491, MMV1581551, MMV011565, MMV1581558, MMV1578577, MMV233495 and MMV1580482, firstly described here as anti-T. gondii agents. RWJ-67657 emerges as a valuable drug candidate for experimental chronic cerebral toxoplasmosis therapy.
Assuntos
Malária , Toxoplasma , Animais , Camundongos , Simulação de Acoplamento Molecular , PandemiasRESUMO
Toxoplasmosis, caused by the obligate intracellular parasite Toxoplasma gondii, affects about one-third of the world's population and can cause severe congenital, neurological and ocular issues. Current treatment options are limited, and there are no human vaccines available to prevent transmission. Drug repurposing has been effective in identifying anti-T. gondii drugs. In this study, the screening of the COVID Box, a compilation of 160 compounds provided by the "Medicines for Malaria Venture" organization, was conducted to explore its potential for repurposing drugs to combat toxoplasmosis. The objective of the present work was to evaluate the compounds' ability to inhibit T. gondii tachyzoite growth, assess their cytotoxicity against human cells, examine their absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties, and investigate the potential of one candidate drug through an experimental chronic model of toxoplasmosis. Early screening identified 29 compounds that could inhibit T. gondii survival by over 80% while keeping human cell survival up to 50% at a concentration of 1 µM. The Half Effective Concentrations (EC50) of these compounds ranged from 0.04 to 0.92 µM, while the Half Cytotoxic Concentrations (CC50) ranged from 2.48 to over 50 µM. Almitrine was chosen for further evaluation due to its favorable characteristics, including anti-T. gondii activity at nanomolar concentrations, low cytotoxicity, and ADMET properties. Administering almitrine bismesylate (Vectarion®) orally at dose of 25 mg/kg/day for ten consecutive days resulted in a statistically significant (p < 0.001) reduction in parasite burden in the brains of mice chronically infected with T. gondii (ME49 strain). This was determined by quantifying the RNA of living parasites using real-time PCR. The presented results suggest that almitrine may be a promising drug candidate for additional experimental studies on toxoplasmosis and provide further evidence of the potential of the MMV collections as a valuable source of drugs to be repositioned for infectious diseases.
Assuntos
COVID-19 , Malária , Toxoplasma , Toxoplasmose , Animais , Camundongos , Almitrina/farmacologia , Almitrina/uso terapêutico , Reposicionamento de Medicamentos , Toxoplasmose/tratamento farmacológico , Toxoplasmose/parasitologiaRESUMO
The Anoplocephalidae family comprises a group of parasites that affect reptiles, birds, and mammals. Humans can be accidentally infected by ingesting contaminated mites. We present a case of human bertiellosis in Brazil. Our report reinforces the importance of correctly identifying the parasite to provide adequate treatment.
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Cestoides , Ácaros , Animais , Humanos , Brasil , Mamíferos , AvesRESUMO
Considering that telomere length can be determined not only by issues related to cell biology but also by aspects related to social factors and environmental exposures, studies on the relationship between social aspects and telomere length can help to better understand the still scarcely known aspects of the human aging process. Thus, this research seeks to verify whether social support networks are associated with telomere length in older adults. This is a cross-sectional study conducted with 448 individuals aged at least 60 years living in the urban area of an inland Brazilian municipality. Relative quantification of telomere length was obtained through real-time qPCR. Social support was assessed through the Medical Outcomes Study Social Support Scale. Descriptive statistics and multiple logistic regression were used in data analysis. The evaluated social support networks for older adults consist in a mean of 16.4 people, and the percentage of older adults who reported up to five members in their network was 27.75%. Shorter telomere length was identified in 25% of the participants, and the older adults who reported having up to five members in their support network were more likely to have a shorter telomere length than those who reported more numerous networks (odds ratio: 1.89, p = 0.011) regardless of gender, age, household arrangement, cognitive decline, and dependence for basic and instrumental activities of daily living, which suggests that measures that stimulate the creation and maintenance of social support networks should be implemented to improve older adults' health.
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Atividades Cotidianas , Vida Independente , Humanos , Idoso , Estudos Transversais , Apoio Social , TelômeroRESUMO
Trypanosoma cruzi, the etiologic agent of Chagas disease, is widely distributed in the Americas and is transmitted through vectorial, transfusional, and oral routes. This study aimed to evaluate the risk of vectorial transmission of Chagas disease in municipalities located in southern Minas Gerais, Brazil, by analyzing triatomine specimens collected from 2014 to 2020. All 1522 hematophagous triatomines were identified as Panstrongylus megistus, and were subjected to parasitological and molecular examinations. From 2014 to 2016, approximately 10% of insects were positive in the microscopic analysis of intestinal content, and 27% were positive as detected by the quantitative polymerase chain reaction (qPCR) of the same sampling. However, in the last investigated years, an increase in infected triatomines was observed in microscopic analysis (22%) and qPCR methods (41%). This corroborates the findings of acute human Chagas disease cases, which have increased in the study area from a maximum of 2 cases in previous years to 20 cases in 2019, and 17 cases in 2020 through June. Additionally, bloodmeal sources of infected triatomines were investigated; human blood was detected in up to 85.7% of the samples. Moreover, canine blood was also detected in triatomine intestinal content in recent years, reaching 91% of analyzed insects in 2018. Data on bloodmeal sources have demonstrated human-vector contact and have suggested the participation of dogs in the parasite transmission cycle. These results indicate the risk of T. cruzi vectorial transmission in Southern Minas Gerais and São Paulo owing to the boundary between these states. Thus, enhanced surveillance and vector control of Chagas disease are highly recommended in these areas.
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Doença de Chagas , Doenças do Cão , Panstrongylus , Animais , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/transmissão , Doença de Chagas/veterinária , Doenças do Cão/epidemiologia , Cães , Humanos , Insetos Vetores , Panstrongylus/parasitologia , Trypanosoma cruziRESUMO
Changes in host immunity and parasite resistance to drugs are among the factors that contribute to decreased efficacy of antiparasitic drugs such as the antimonial compounds pentamidine, amphotericin (AMP B) and miltefosine. Bioactive natural products could be alternatives for the development of new drugs to treat neglected human diseases such as leishmaniasis. Natural coumarins and synthetic analogues have shown leishmanicidal activity, mainly in vitro. This study investigated the in vitro and in vivo leishmanicidal activity of synthetic coumarin compounds (C1-C5) in parasites Leishmania (L.) amazonensis and L. (L.) infantum chagasi. The cytotoxicity of these compounds in mammalian cells and their influence on production of reactive oxygen species was also investigated. In vitro assays showed that 8-methoxy-3-(4-nitrobenzoyl)-6-propyl-2H-chromen-2-one (C4) was as active as AMP B mainly in the amastigote form (p < 0.05); C4 presented a selectivity index (65.43) four times higher than C2 (15.4) in L. amazonensis and six times higher (33.94) than C1 (5.46) in L. infantum chagasi. Additionally, coumarin C4 reduced the H2O2 concentration 32.5% more than the control group in L. amazonensis promastigotes during the lag phase of proliferation. No interference of C4 was observed on the mitochondrial membrane potential of the parasites. In vivo, coumarin C4 in corn oil (oral route) led to a reduction in the number of amastigotes from L. infantum chagasi to 1.31 × 106 and 4.09 × 104 in the spleen and liver, respectively (p < 0.05). Thus, C4 represents a candidate for further studies aiming at new treatments of leishmaniasis.
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Antiprotozoários/farmacologia , Cumarínicos/farmacologia , Leishmania/efeitos dos fármacos , Leishmaniose/prevenção & controle , Administração Oral , Anfotericina B/administração & dosagem , Anfotericina B/química , Anfotericina B/farmacologia , Animais , Antiprotozoários/administração & dosagem , Antiprotozoários/química , Cumarínicos/administração & dosagem , Cumarínicos/química , Cricetinae , Feminino , Interações Hospedeiro-Parasita/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Leishmania/classificação , Leishmania/fisiologia , Leishmaniose/parasitologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mesocricetus , Estrutura Molecular , Especificidade da EspécieRESUMO
A new series of silver compounds could be of interest on designing new drugs for the treatment of leishmaniasis. The compounds [Ag(phen)(imzt)]NO3(1), [Ag(phen)(imzt)]CF3SO3(2), [Ag(phen)2](BF4)·H2O (3), [Ag2(imzt)6](NO3)2(4), and imzt have been synthesized and evaluated in vitro for antileishmanial activity against Leishmania. (L.) amazonensis (La) and L. (L.) chagasi (Lc), and two of them were selected for in vivo studies. In addition to investigating the action on Leishmania, their effects on the hydrogen peroxide production and cysteine protease inhibition have also been investigated. As for antileishmanial activity, compound (4) was the most potent against promastigote and amastigote forms of La (IC50 = 4.67 and 1.88 µM, respectively) and Lc (IC50 = 9.35 and 8.05 µM, respectively); and comparable to that of amphotericin B, reference drug. Beside showing excellent activity, it also showed a low toxicity. In the in vivo context, compound (4) reduced the number of amastigotes in the liver and spleen when compared to the untreated group. In evaluating the effect of the compounds on Leishmania, the level of hydrogen peroxide production was maintained between the lag and log phases; however, in the treatment with compound (4) it was possible to observe a reduction of 25.44 and 49.13%, respectively, in the hydrogen peroxide rates when compared to the lag and log phases. It was noticed that the presence of a nitrate ion and imzt in compound (4) was important for the modulation of the antileishmanial activity. Thus, this compound can represent a potentially new drug for the treatment of leishmaniasis.
Assuntos
Complexos de Coordenação/farmacologia , Imidazolidinas/farmacologia , Tionas/farmacologia , Tripanossomicidas/farmacologia , Animais , Complexos de Coordenação/síntese química , Complexos de Coordenação/toxicidade , Feminino , Imidazolidinas/síntese química , Imidazolidinas/toxicidade , Leishmania infantum/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Mesocricetus , Camundongos , Testes de Sensibilidade Parasitária , Prata/química , Tionas/síntese química , Tionas/toxicidade , Tripanossomicidas/síntese química , Tripanossomicidas/toxicidadeRESUMO
Dogs are important hosts and reservoirs of leishmaniasis, a disease caused by protozoan parasites from the genus Leishmania, affecting ~12 million people worldwide. The detection of visceral leishmaniasis (VL) in dogs by real-time PCR (qPCR) may improve on diagnosis, but the different qPCR methods available for Leishmania DNA detection have not been established as routine in diagnostic tools and/or epidemiologic studies for canine VL. Here, we compared three qPCR assays (DNApol, Linj31, and LDON) in the detection of VL by Leishmania infantum in spleen (n = 48; 7), skin (n = 48; 7), and whole blood (n = 44; 7) samples from serologically positive and negative dogs, respectively. Overall, the DNApol performed better than the Linj31 and LDON assays in the detection of positive samples in all tissues tested, yielding from 66.7 to 100.0% of positivity for both skin and spleen samples. For spleen samples, we observed no statistically significant differences between positive detection by the LDON and DNApol assays. Whole blood samples yielded the lowest rates of positive detection, regardless of the qPCR assay used. In contrast, positive detection of Leishmania DNA was as efficient from skin samples using the DNApol assay as from spleen samples using either the DNApol or the LDON assay. Although qPCR assays from skin samples may not be practical for use in the field, our study suggests that the DNApol and LDON assays from skin samples could be used in future to evaluate canine VL treatment in veterinary clinics.
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Doenças do Cão/parasitologia , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/veterinária , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Bioensaio , DNA de Protozoário/genética , Cães , Feminino , Leishmania infantum/genética , Leishmania infantum/imunologia , Leishmaniose Visceral/parasitologia , Masculino , Pele/parasitologia , Baço/parasitologiaRESUMO
Bioactive molecules stored in dentin, such as transforming growth factor beta1 (TGF-b1), may be involved in the signaling events related to dental tissue repair. The authors conducted an in vitro evaluation of the amount of TGF-b1 released from dentin slices after treatment with 10% ethylenediaminetetraacetic acid (EDTA), 2.5% sodium hypochlorite (NaOCl) or phosphate-buffered saline (PBS), and the effect of this growth factor on stem cell migration from human exfoliated deciduous teeth (SHED). Sixty 1-mm-thick tooth slices were prepared with or without the predentin layer, and treated with either 10% EDTA for 1 minute, 2.5% NaOCl for 5 days or kept in PBS. Tooth slice conditioned media were prepared and used for TGF-b1 ELISA and migration assays. Culture medium with different concentrations of recombinant human TGF-b1 (0.5, 1.0, 5.0 or 10.0 ng/mL) was also tested by migration assay. The data were evaluated by ANOVA and Tukey's test. Optical density values corresponding to media conditioned by tooth slices either containing or not containing the predentin layer and treated with 10% EDTA were statistically greater than the other groups and close to 1 ng/mL. Increased rates of migration toward media conditioned by tooth slices containing the predentin layer and treated with PBS, 10% EDTA or 2.5% NaOCl were observed. Recombinant human TGF-b1 also stimulated migration of SHED, irrespective of the concentration used. EDTA may be considered an effective extractant of TGF-b1 from the dentin matrix. However, it does not impact SHED migration, suggesting that other components may account for the cell migration.
Assuntos
Movimento Celular/efeitos dos fármacos , Polpa Dentária/citologia , Dentina/efeitos dos fármacos , Ácido Edético/farmacologia , Irrigantes do Canal Radicular/farmacologia , Células-Tronco/efeitos dos fármacos , Fator de Crescimento Transformador beta1/efeitos dos fármacos , Análise de Variância , Células Cultivadas , Meios de Cultivo Condicionados , Polpa Dentária/efeitos dos fármacos , Dentina/ultraestrutura , Ensaio de Imunoadsorção Enzimática , Matriz Extracelular/efeitos dos fármacos , Humanos , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes , Hipoclorito de Sódio/farmacologia , Células-Tronco/fisiologia , Dente Decíduo/citologia , Dente Decíduo/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismoRESUMO
Visceral leishmaniasis is a systemic and chronic disease and dogs are the main reservoir of the etiologic agent, Leishmania infantum (syn L. chagasi). A serological and molecular investigation of canine visceral leishmaniasis (CVL) was performed in the municipality of Alfenas, located in the southern region of Minas Gerais, where the disease is not endemic. Samples from 87 dogs were submitted to serological tests including the Dual Path Platform (DPP (r) ) CVL Bio-Manguinhos rapid test, an in-house enzyme-linked immunosorbent assay (ELISA) and an immunofluorescence antibody test (IFAT), as well as molecular techniques such as a conventional polymerase chain reaction (PCR) with the RV1/RV2 primers and a quantitative PCR (qPCR) with the LinJ31, Ldon and DNApol primers. Of the 87 serum samples, eight (9.2%) were positive for Leishmania using the DPP rapid test, but only four (4.6%) were confirmed by ELISA and two (2.3%) by IFAT. In these two serologically confirmed cases, spleen and liver samples were positive by all the employed molecular and parasitological procedures performed on spleen samples. When whole blood samples were used in the molecular assays, two samples (2.3%) were positive only by qPCR. DNA extracted and amplified from the spleens of seropositive dogs was sequenced, showing 100% of similarity with the Leishmania infantum (syn L. chagasi) sequence. Thus, the first cases of CVL have been confirmed in the Alfenas region, suggesting the importance of canine surveys in non-endemic municipalities for CVL to monitor disease progression and to prevent outbreaks.
Assuntos
Anticorpos Antiprotozoários/sangue , Doenças do Cão/epidemiologia , Leishmania infantum , Leishmaniose Visceral/veterinária , Animais , Brasil/epidemiologia , Doenças do Cão/diagnóstico , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Imunofluorescência , Leishmania infantum/genética , Leishmania infantum/imunologia , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real/veterináriaRESUMO
Abstract: Bioactive molecules stored in dentin, such as transforming growth factor beta1 (TGF-b1), may be involved in the signaling events related to dental tissue repair. The authors conducted an in vitro evaluation of the amount of TGF-b1 released from dentin slices after treatment with 10% ethylenediaminetetraacetic acid (EDTA), 2.5% sodium hypochlorite (NaOCl) or phosphate-buffered saline (PBS), and the effect of this growth factor on stem cell migration from human exfoliated deciduous teeth (SHED). Sixty 1-mm-thick tooth slices were prepared with or without the predentin layer, and treated with either 10% EDTA for 1 minute, 2.5% NaOCl for 5 days or kept in PBS. Tooth slice conditioned media were prepared and used for TGF-b1 ELISA and migration assays. Culture medium with different concentrations of recombinant human TGF-b1 (0.5, 1.0, 5.0 or 10.0 ng/mL) was also tested by migration assay. The data were evaluated by ANOVA and Tukey's test. Optical density values corresponding to media conditioned by tooth slices either containing or not containing the predentin layer and treated with 10% EDTA were statistically greater than the other groups and close to 1 ng/mL. Increased rates of migration toward media conditioned by tooth slices containing the predentin layer and treated with PBS, 10% EDTA or 2.5% NaOCl were observed. Recombinant human TGF-b1 also stimulated migration of SHED, irrespective of the concentration used. EDTA may be considered an effective extractant of TGF-b1 from the dentin matrix. However, it does not impact SHED migration, suggesting that other components may account for the cell migration.
Assuntos
Humanos , Irrigantes do Canal Radicular/farmacologia , Células-Tronco/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Ácido Edético/farmacologia , Polpa Dentária/citologia , Dentina/efeitos dos fármacos , Fator de Crescimento Transformador beta1/efeitos dos fármacos , Hipoclorito de Sódio/farmacologia , Células-Tronco/fisiologia , Dente Decíduo/citologia , Dente Decíduo/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Microscopia Eletrônica de Varredura , Células Cultivadas , Reprodutibilidade dos Testes , Análise de Variância , Meios de Cultivo Condicionados , Polpa Dentária/efeitos dos fármacos , Dentina/ultraestrutura , Matriz Extracelular/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismoRESUMO
Visceral leishmaniasis represents an important public health issue in different parts of the world, requiring that measures be put in place to control the spread of the disease worldwide. The canine leishmaniasis diagnosis is not easy based on clinical signs, since dogs may not develop the infection with recognizable signs. Thus, the laboratorial diagnosis is essential to ascertain the incidence and prevalence of canine leishmaniasis especially in areas with major control efforts. Although, the diagnosis can be performed by the use of different approaches, the molecular methods such as PCR have become an indispensable tool for leishmaniases diagnosis. A TaqMan assay for real-time PCR (Linj31-qPCR) was developed to determine the parasite occurrence in clinical cases of leishmaniasis. The assay targets an L. (L.) infantum hypothetical protein region. The specificity of the assay was verified by using Leishmania World Health Organization reference strains including parasites belonging to subgenus L. (Leishmania), subgenus L. (Viannia), other Leishmania species and Trypanosoma cruzi. The sensitivity was verified by using isolates of L. (L.) amazonensis and L. (L.) infantum. The usefulness of the assay for diagnosis was ascertained by testing 277 samples from dogs in regions endemic for visceral and/or cutaneous leishmaniasis and from regions in which leishmaniasis was not endemic in São Paulo State, Brazil. Diagnosis of canine visceral leishmaniasis (CVL) was determined on these animals by conventional PCR and three serological tests. The dog samples were divided into four groups. I, dogs with CVL (n = 101); II, dogs with other diseases and without CVL (n = 97); III, dogs with American cutaneous leishmaniasis (n = 7), and, IV, dogs without CVL (n = 72) from areas where leishmaniasis was not endemic as control group. Results indicated that Linj31-qPCR was able to identify parasites belonging to subgenus L. (Leishmania) with no cross-amplification with other parasite subgenera. The Linj31-qPCR detected Leishmania parasites DNA in 98% of samples from Group I. In conclusion this methodology can be used as routine diagnostic tools to detect parasites from subgenus Leishmania.
Assuntos
Doenças do Cão/diagnóstico , Leishmania infantum/genética , Leishmaniose Visceral/veterinária , Proteínas de Protozoários/genética , Animais , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Doenças do Cão/parasitologia , Cães , Leishmania/química , Leishmania/classificação , Leishmania/genética , Leishmania infantum/química , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/parasitologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Padrões de Referência , Sensibilidade e EspecificidadeRESUMO
Leishmania spp. is a protozoan that maintains its life cycle in domestic and wild animals and it may include bats, a population that has increased in urban environments. This study aimed to investigate the presence of Leishmania spp. in bats captured strictly in urban areas that are endemic for visceral leishmaniasis. The spleen and skin samples of 488 bats from 21 endemic cities in northwestern São Paulo State, Brazil, were tested for the presence of Leishmania kDNA using real-time PCR. Differentiation from Trypanosoma spp. was achieved by amplifying a DNA fragment of the ribosomal RNA gene. The presence of Leishmania spp. kDNA was verified in 23.9% of bats and Trypanosoma spp. DNA was identified in 3.9%. Leishmania species differentiation revealed the presence of Leishmania amazonensis in 78.3% of the bats; L. infantum in 17.4%, and 1 sample (4.3%) showed a mix pattern of L. infantum and L. amazonensis. We also detected, for the first time, L. infantum and L. amazonensis DNA in Desmodus rotundus, the hematophagous bat. The presence of Leishmania spp. DNA in bats strictly from urban areas endemic for visceral leishmaniasis in the State of São Paulo, Brazil indicates that these wild and abundant animals are capable of harboring Leishmania spp. in this new scenario. Due to their longevity, high dispersion capacity and adaptability to synanthropic environments, they may play a role in the maintenance of the life cycle of Leishmania parasites.
Assuntos
Quirópteros/parasitologia , Leishmania/isolamento & purificação , Leishmaniose Visceral/epidemiologia , Animais , Animais Selvagens/parasitologia , Brasil/epidemiologia , Reservatórios de Doenças , Geografia , Leishmania/genética , Leishmaniose Visceral/parasitologia , Reação em Cadeia da Polimerase em Tempo Real , População UrbanaRESUMO
A leishmaniose visceral americana (LVA) é um sério problema de saúde pública. No período de 2003 a 2009 foram registrados no Brasil mais de 34 mil casos de leishmaniose visceral. Até a década de 80, a maioria dos casos concentrava-se em áreas rurais dos municípios. Esse perfil mudou e vários casos são notificados nas áreas urbanas. No Estado de São Paulo a doença é autóctone desde 1998. A partir de 2003 foram registrados também casos autóctones caninos nas redondezas da região metropolitana de São Paulo. Uma das formas de se avaliar a propagação da infecção é o estudo dos transmissores. Embora Lutzomyia longipalpis seja uma espécie prevalente em zonas urbanas, tem sido a única responsável pela transmissão na área urbana dos municípios da região Oeste do Estado. Contudo, na Região Metropolitana de São Paulo a sua presença ainda não foi detectada. Este fenômeno leva a supor que outra espécie de flebotomíneos ou outros ectoparasitas de cães como os carrapatos Rhipicephalus sanguineus e as pulgas Ctenocephalides felis felis possam estar envolvidos na transmissão da LVA. Este estudo mostra que os cães estão densamente infestados por pulgas e carrapatos em todos os estádios evolutivos. Além disso, material genético positivo para L. (L.) infantum chagasi, foi encontrado no interior desses ectoparasitas com uma positividade variando de 53,1% nas pulgas a 77,7% nas ninfas, inclusive após a ecdise de ninfa para o estádio adulto sugerindo a capacidade dos carrapatos de preservar parasitas vivos. Com a utilização da PCR em tempo real, foi possível quantificar o DNA presente no interior dos ectoparasitas. A PCR em tempo real single se mostrou eficiente na detecção de espécies do subgênero Leishmania e com a PCR multiplex foi possíveldiferenciar entre as espécies dos subgênero Viannia e as do complexodonovani. O marcador molecular (CY5) da PCR em tempo real multiplex foicapaz detectar todas as espécies de Leishmania spp analisadas sendo útilpara detectar...
Assuntos
Animais , Cães , Artrópodes , Leishmaniose Visceral , RNA Mensageiro , Reação em Cadeia da Polimerase em Tempo Real , Carrapatos , SifonápterosRESUMO
BACKGROUND: Cerebral toxoplasmosis (CT) continues to cause significant morbidity and mortality in human immunodeficiency virus (HIV)-infected patients in Brazil. In clinical practice, the initial diagnosis is usually presumptive and alternative diagnosis tools are necessary. Our objective was to evaluate whether the detection of high titers of IgG anti-Toxoplasma gondii and T. gondii DNA in blood samples are associated with the diagnosis of CT. METHODS: In this case-control study we included 192 patients with HIV-1 infection: 64 patients with presumptive CT (cases) and 128 patients with other diseases (controls). Blood samples to perform indirect immunofluorescense reaction (IFI) to detect anti-T. gondii IgG antibodies and polymerase chain reaction (PCR) were collected before or within the first three days of anti-Toxoplasma therapy. Two multivariate logistic regression models were performed: one including the variable qualitative serology and another including quantitative serology. RESULTS: In the first model, positive IgG anti-T. gondii (OR 4.7, 95% CI 1.2-18.3; p = 0.027) and a positive T. gondii PCR result (OR 132, 95% CI 35-505; p < 0.001) were associated with the diagnosis. In the second model, IgG anti-T. gondii titres > 1:1024 (OR 7.6, 95% CI 2.3-25.1; p = 0.001) and a positive T. gondii PCR result (OR 147, 95% CI 35-613; p < 0.001) were associated with the diagnosis. CONCLUSIONS: Quantitative serology and molecular diagnosis in peripheral blood samples were independently associated with the diagnosis of CT in HIV-infected patients. These diagnostic tools can contribute to a timely diagnosis of CT in settings where Toxoplasma infection is common in the general population.
Assuntos
Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Anticorpos Antiprotozoários/sangue , DNA de Protozoário/sangue , Imunoglobulina G/sangue , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Cerebral/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/parasitologia , Adulto , Estudos de Casos e Controles , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Masculino , Reação em Cadeia da Polimerase , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Cerebral toxoplasmosis (CT) continues to cause significant morbidity and mortality in human immunodeficiency virus (HIV)-infected patients in Brazil. In clinical practice, the initial diagnosis is usually presumptive and alternative diagnosis tools are necessary. Our objective was to evaluate whether the detection of high titers of IgG anti-Toxoplasma gondii and T. gondii DNA in blood samples are associated with the diagnosis of CT. METHODS: In this case-control study we included 192 patients with HIV-1 infection: 64 patients with presumptive CT (cases) and 128 patients with other diseases (controls). Blood samples to perform indirect immunofluorescense reaction (IFI) to detect anti-T. gondii IgG antibodies and polymerase chain reaction (PCR) were collected before or within the first three days of anti-Toxoplasma therapy. Two multivariate logistic regression models were performed: one including the variable qualitative serology and another including quantitative serology. RESULTS: In the first model, positive IgG anti-T. gondii (OR 4.7, 95 percent CI 1.2-18.3; p = 0.027) and a positive T. gondii PCR result (OR 132, 95 percent CI 35-505; p < 0.001) were associated with the diagnosis. In the second model, IgG anti-T. gondii titres > 1:1024 (OR 7.6, 95 percent CI 2.3-25.1; p = 0.001) and a positive T. gondii PCR result (OR 147, 95 percent CI 35-613; p < 0.001) were associated with the diagnosis. CONCLUSIONS: Quantitative serology and molecular diagnosis in peripheral blood samples were independently associated with the diagnosis of CT in HIV-infected patients. These diagnostic tools can contribute to a timely diagnosis of CT in settings where Toxoplasma infection is common in the general population.
Assuntos
Adulto , Feminino , Humanos , Masculino , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Anticorpos Antiprotozoários/sangue , DNA de Protozoário/sangue , Imunoglobulina G/sangue , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Cerebral/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/parasitologia , Estudos de Casos e Controles , Técnica Indireta de Fluorescência para Anticorpo , Reação em Cadeia da Polimerase , Sensibilidade e EspecificidadeRESUMO
A toxoplasmose é uma das mais comuns infecções parasitárias com alta prevalência em humanos. É uma infecção de caráter oportunista que acomete principalmente mulheres grávidas e pode ameaçar a vida dos pacientes imunocomprometidos, principalmente aqueles com a síndrome da imunodeficiência adquirida (AIDS). Ela é causada por Toxoplasma gondii, um protozoário parasita intracelular obrigatório. A doença pode causar danos graves no sistema nervoso central pela ocorrência da encefalite toxoplásmica. A doença cerebral era uma rara infecção antes da epidemia da AIDS, tornando-se a causa mais comum de lesões expansivas intracranianas e a terceira doença definidora de AIDS. Este estudo avaliou o diagnóstico molecular e imunológico da toxoplasmose cerebral e determinou os perfis sorológicos dos pacientes. Foram analisadas as 256 amostras obtidas de 207 pacientes divididos em dois grupos. O grupo I foi composto de 64 pacientes com toxoplasmose cerebralobtendo um total de 82 amostras (64 de sangue e 18 de LCR). O grupo II foi composto de 143 pacientes com outras doenças oportunistas, sendo 95 neurológicas e 79 doenças sistêmicas, obtendo um total de 174 amostras(128 de sangue e 46 de LCR). A análise molecular das amostras foi realizada pela reação da polimerase em cadeia (PCR), utilizando iniciadores B22 e B23 do gene B1, e a análise imunológica pela imunofluorescênciaindireta (IFI) e pela reação imunoenzimática (ELISA). A PCR mostrou ser igualmente sensível e muito mais específica que os testes imunológicos na análise das amostras de LCR e sangue. O grave envolvimento neurológico na maioria dos pacientes estudados e a altaprevalência de toxoplasmose no Brasil podem ter contribuído para o aumento da sensibilidade da PCR. Os perfis sorológicos dos pacientes do grupo I apresentaram títulos significativamente mais altos daqueles encontrado no grupo II, e sugerem a presença da toxoplasmose cerebral ou um alto risco ...