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1.
Artigo em Inglês | MEDLINE | ID: mdl-32065095

RESUMO

BACKGROUND: Drugs used for Parkinson's disease (PD) are based only on relieving main symptoms, but may present several side effects that are typical of such pharmacological treatment. METHODS: This study aimed to use in silico methods for drug designing inhibitors of PD therapeutic target monoamine oxidase B (MAO-B). Thus, 20 MAO-B inhibitors from BindingDB database were selected, then it was performed a calculation of their descriptors at DFT B3LYP/6-31G** level of theory. RESULTS: Statistical analysis considering a Pearson correlation matrix, led to the selection of electrophilicity index as a descriptor related to the biological activity of inhibitors. Furthermore, based on the prediction of suitable ADME/Tox properties, the molecule CID 54583085 was selected as a template to carry out structural modifications to obtain 3 analogues, whereas molecules B and C showed significant improvement in mutagenicity and carcinogenicity, in relation to the template. CONCLUSION: Thus, it is concluded that the proposed modifications led us to satisfactory results, since there was an improvement in toxicological properties of molecules, however, further studies must be carried out to evaluate their biological activities as possible MAO-B inhibitors for PD treatment.

2.
Anat Sci Int ; 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32078150

RESUMO

Sunao Tawara, who was born in 1873 and died in 1952, is considered the father of modern cardiac electrophysiology. He published his monumental monograph describing the atrioventricular conduction axis in 1906. He achieved this task in the face of multiple tribulations as a doctoral student working in a cultural environment that was not his own. Although his letters underscoring the publication of the monograph have been published, little emphasis has been placed on the potential problems he encountered in bringing his task to fruition. For example, it was not until the final 6 months of his studies that he resolved the issue of the connection between the atrioventricular bundle and the so called "Purkinje cardiomyocytes". His exchanges with his mentor, Ludwig Aschoff, emphasized that the difficulties he encountered in making the connection caused him quite some turmoil. We believe that this issue, and others that he identified in his correspondence, are worthy of further attention.

3.
Rev Soc Bras Med Trop ; 53: e20190364, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31994667

RESUMO

The present report describes the first case of postpartum disseminated histoplasmosis in a 24-year-old HIV-negative woman. On the tenth day after vaginal delivery, the patient presented with dyspnea, fever, hypotension, tachycardia, and painful hepatomegaly. Yeast-like Histoplasma capsulatum features were isolated in the buffy coat. The phylogenetic analysis demonstrated that the fungal isolate was similar to other H. capsulatum isolates identified in HIV patients from Ceará and Latin America. Thus, histoplasmosis development in individuals with transitory immunosuppression or during the period of immunological recovery should be carefully examined.

4.
Environ Monit Assess ; 192(2): 88, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31900672

RESUMO

The formation of an oil-suspended particulate material aggregate (OSA) is one of the weathering processes that occur after the spill of oil in marine environments, responsible for the dispersion of hydrocarbons. Oil and particle aggregates are formed from the interaction between small oil droplets and suspended particulate matter (SPM). In general, SPM are fine particles which may be inorganic minerals or organic particles in the water column. OSAs provide vertical dispersion of oil along the water column depending on the acquired density (buoyancy), and may remain near the surface, water column, or bottom of water bodies. The present study examines the formation of these aggregates through the laboratory simulation of an oil spill in the waters of the São Paulo river estuary. The main objective was to investigate the dispersion of polycyclic aromatic hydrocarbons (PAHs), verifying which estuary characteristics most influenced the formation of OSAs and in addition to determine the regions of probable ecotoxicological impact due to the negative buoyancy of the formed aggregate. The results show that there was greater dispersion to the water column, mainly of lighter PAHs, ranging from 85,804.05 ng g-1 (P11C) to 566,989.84 ng g-1 (P17C). The percentage of dispersed PAH concentration per experimental unit ranged from 9.90% in unit P2 to 75.27% in unit P18. The formation of OSAs was influenced mainly by salinity and chlorophyll a. As the most vulnerable regions, the impacts are one mouth (P2 and P4), one central region (P7, P8, and P10), and one source (P18).


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Clorofila A , Ecotoxicologia , Estuários , Sedimentos Geológicos , Material Particulado/análise , Poluição por Petróleo/análise , Rios , Salinidade
5.
Clin Infect Dis ; 70(3): 518-520, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31638142

RESUMO

We describe a second case of human infection caused by Thelazia gulosa (the cattle eye worm), likely acquired in California. For epidemiologic purposes, it is important to identify all Thelazia recovered from humans in North America to the species level.

6.
Mycoses ; 63(2): 145-150, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31715053

RESUMO

Cryptococcal meningitis is a several disease common in late stage of HIV infection. Detection of cryptococcal antigen (CrAg) is an important for early diagnosis of this invasive mycosis. The pre-emptive treatment for isolated antigenemia prevents the onset of meningoencephalitis. Screening CrAg in patients with low CD4 count is cost-effective in countries with prevalence of antigenemia above 3%. However, in Brazil, the number of prevalence studies on cryptococcosis and HIV is insufficient. The objective of this study is to estimate the prevalence of CrAg and describe clinical characteristics from a cohort of patients followed at a reference center in Brazil. CrAg screening was performed in 89 inpatients with CD4 count ≤200 cells/mm3 or WHO stage III/IV from the National Institute of Infecttious Disease, Rio de Janeiro. Patients with isolated antigenemia received pre-emptive therapy with fluconazole and patients with meningoencephalitis were treated with Amphotericin B. Individuals were followed up for 12 months. Prevalence of serum CrAg was 11.23%, cryptococcal meningoencephalitis 6.74% and isolated antigenemia 4.81%. None of the patients with isolated antigenemia developed meningoencephalitis during the follow up. Signs and symptoms of meningoencephalitis were unspecific or absent. Our study suggests the need of CrAg screening in Brazil and highlights that lumbar puncture is mandatory in all individuals CrAg positive to exclude asymptomatic meningoencephalitis.

7.
Heart Rhythm ; 17(1): 123-130, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31377422

RESUMO

BACKGROUND: The right ventricular outflow tract is the most common source of ventricular arrhythmias in nonstructural heart disease. Most of these arrhythmias are of endocardial origin, but their morphologic substrate is mostly unknown. OBJECTIVE: The purpose of this study was to identify potential morphologic substrates for such arrhythmias originating within the right ventricular outflow tract. METHODS: Three adult human hearts that had been fixed in 4% formaldehyde were examined. In 2 of the hearts, which were obtained subsequent to necropsies, the base of the anterior papillary muscle of the tricuspid valve was removed at the site of its fusion with the moderator band. The block of removed myocardium was submitted to routine histologic processing and sectioned at 5-µm thickness. The free-standing subpulmonary infundibulum also was removed as a series of macroscopic preparations, which were sectioned in their short axis at 5-µm thickness. The third heart was assessed using microcomputed tomography after it had been stained with 7.5% I2KI contrast agent for 14 days, with the contrast agent refreshed on the seventh day. RESULTS: Specialized conducting cardiomyocytes from the base of the anterior papillary muscle to the supraventricular crest and subpulmonary infundibulum were identified and tracked using histology in 2 hearts and microcomputed tomography in the other. Transitional cells were also found at these sites. CONCLUSION: The existence of such specialized cardiomyocytes within the infundibulum is of clinical significance because they could be the morphologic substrate for arrhythmias known to originate from these sites.

8.
Mycopathologia ; 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31845177

RESUMO

Histoplasmosis is considered the most common invasive opportunistic fungal disease in the Americas, with outbreaks and micro-epidemics reported for over 80 years. In Brazil, this disease has been described since 1946, reaching a remarkable incidence in the population, especially during the HIV-AIDS pandemic. In this study, published and unpublished outbreaks and micro-epidemics of histoplasmosis in Brazil were revisited by accessing different database sources and evaluating epidemiological and clinical features. We have found reports spanning 1946-2017, across 10 Brazilian states and with involvement of 370 humans and 2 dogs, and 13 disseminated cases and 3 deaths were reported. Rio de Janeiro had the largest number of outbreaks (n = 20/40; 50%) reported in this study. The majority of outbreaks and micro-epidemics was reported in caves (n = 21/40; 52.5%), followed by reports in abandoned/deactivated sites (n = 6/40; 15%), mines (n = 5/40; 12.5%), chicken coops (n = 4/40; 10%). Histoplasmosis is a serious health issue in Brazil considering the attractive and growing market of ecotourism throughout more than 7000 caves, and all levels of poultry farming activity are important to raise awareness about how dangerous this neglected disease can be and establish ways to decrease exposure to contaminated environmental sources through adequate preventive measures.

9.
Clin Anat ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31749249

RESUMO

It was Sunao Tawara who, in 1906, established the foundations for knowledge of the arrangement of the atrioventricular conduction axis in man and other mammals. Study of the hearts of ungulates was a central part in his investigation, which assessed other species, including man. He described several subtle differences between the mammals. We have now ourselves studied the cardiac conduction tissue of the ox heart, comparing our findings with our knowledge of the arrangement in man, and providing new insights into the differences illustrated by Tawara. It is, perhaps, surprising that these differences, although subtle, have not attracted more attention. We show that the major difference is the fact that the noncoronary aortic sinus in the ox heart is mainly supported by the myocardium of the ventricular septum, whereas in the human heart the sinus, and its leaflet, are in fibrous contiguity with the aortic leaflet of the mitral valve. It is this feature that determines the difference in the arrangement of the conduction axis between the species. We also show that the emergence of the left bundle branch on the left ventricular aspect of the muscular septum is more variable than previously described. Clin. Anat., 2019. © 2019 Wiley Periodicals, Inc.

10.
Sci Rep ; 9(1): 11789, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409874

RESUMO

Histoplasmosis is a worldwide-distributed deep mycosis that affects healthy and immunocompromised hosts. Severe and disseminated disease is especially common in HIV-infected patients. At least 11 phylogenetic species are recognized and the majority of diversity is found in Latin America. The northeastern region of Brazil has one of the highest HIV/AIDS prevalence in Latin America and Ceará State has one of the highest death rates due to histoplasmosis in the world, where the mortality rate varies between 33-42%. The phylogenetic distribution and population genetic structure of 51 clinical isolates from Northeast Brazil was studied. For that morphological characteristics, exoantigens profile, and fungal mating types were evaluated. The genotypes were deduced by a MSLT in order to define local population structure of this fungal pathogen. In addition, the relationships of H. capsulatum genotypes with clinically relevant phenotypes and clinical aspects were investigated. The results suggest two cryptic species, herein named population Northeast BR1 and population Northeast BR2. These populations are recombining, exhibit a high level of haplotype diversity, and contain different ratios of mating types MAT1-1 and MAT1-2. However, differences in phenotypes or clinical aspects were not observed within these new cryptic species. A HIV patient can be co-infected by two or more genotypes from Northeast BR1 and/or Northeast BR2, which may have significant impact on disease progression due to the impaired immune response. We hypothesize that co-infections could be the result of multiple exposure events and may indicate higher risk of disseminated histoplasmosis, especially in HIV infected patients.

11.
Int. j. cardiovasc. sci. (Impr.) ; 32(4): 396-407, July-Aug. 2019. graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1012340

RESUMO

The use of technology has increased tremendously, by means of more reliable, smaller, more accessible and specially more user-friendly devices, which provide a wider range of features, and promote significant benefits for the population and health professionals. It is in this context that monitors and apps for heart rate (HR) measurement have emerged. HR is a clinical vital sign of diagnostic and prognostic importance. In response to body movement, HR tends to increase, in a direct relationship with the intensity of exercise. HR was primarily measured by the count of arterial pulse, and recently, HR can be precisely measured by monitors, bracelets and smartphone apps capable to perform real-time measurements and storage of data. This paper aimed to make a brief and updated review on the theme, providing a broader view of advantages and limitations of these resources for HR measurement in exercise. HR monitors and apps use basically two types of technology, optical sensor (photoplethysmography) and electrical signal from the heart. In general, these devices have shown good accuracy in measuring HR and HR variability at rest, but there are differences between brands and models considering the type, mode and intensity of exercise. HR measurements by monitors and smartphone apps are simple, accessible and may help cardiologists in the monitoring of the intensity of aerobic exercise, focusing on health promotion and on primary and secondary prevention of cardiovascular diseases


Assuntos
Humanos , Masculino , Feminino , Palpação/métodos , Exercício , Monitores de Aptidão Física , Frequência Cardíaca , Arritmias Cardíacas , Prognóstico , Esportes , Débito Cardíaco , Doenças Cardiovasculares/diagnóstico , Tecnologia Biomédica , Teste de Esforço/métodos
12.
Int J Infect Dis ; 86: 147-156, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31330326

RESUMO

BACKGROUND: Histoplasmosis is a systemic disease caused by the dimorphic fungus Histoplasma capsulatum. Diagnosis is often delayed, or it is misdiagnosed as tuberculosis. In Brazil, the infection is common and cases of histoplasmosis have been described in all regions of the country; however, the real problem is underestimated since notification of histoplasmosis is not mandatory. METHODS: Human histoplasmosis cases diagnosed in Brazil and published up to December 2018 were identified through a search conducted in the PubMed/MEDLINE, SciELO, and Web of Science databases. Moreover, the isolation of H. capsulatum from animals or environmental sources in Brazil was also evaluated. RESULTS: A total of 207 articles fulfilled the inclusion criteria and were evaluated, involving a total of 3530 patients with a diagnosis of histoplasmosis during the period studied. Of these patients, 78.3% were male, giving a male-to-female ratio of approximately 4:1. Histoplasmosis presented a higher frequency in individuals between the fourth and fifth decades of life. Disseminated disease was the most common form of histoplasmosis. Isolation of H. capsulatum on culture media and histopathology using staining methods were the diagnostic methods with the best efficiency. The best results in the identification of the H. capsulatum were achieved for samples from mononuclear phagocyte system components, skin and mucosa, and hematological samples. Regarding predisposing factors for histoplasmosis, HIV infection was the most common underlying condition. The overall mortality rate was 33.1%. CONCLUSIONS: This study represents the first available systematic review demonstrating Brazilian cases of histoplasmosis in the literature and highlights that the disease is more widespread in the Brazilian territory than has previously been thought.


Assuntos
Histoplasmose/epidemiologia , Animais , Brasil/epidemiologia , Feminino , Infecções por HIV/complicações , Histoplasma/isolamento & purificação , Histoplasmose/complicações , Histoplasmose/diagnóstico , Humanos , Masculino
13.
Cent Nerv Syst Agents Med Chem ; 19(2): 75-99, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31057125

RESUMO

INTRODUCTION: Neurodegenerative diseases (NDDs) are progressive, directly affecting the central nervous system (CNS), the most common and recurrent are Alzheimer's disease (AD) and Parkinson's disease (PD). One factor frequently mentioned in the etiology of NDDs is the generation of free radicals and oxidative stress, producing cellular damages. Studies have shown that the consumption of foods rich in polyphenols, especially those of the flavonoid class, has been related to the low risk in the development of several diseases. Due to the antioxidant properties present in the food, a fruit that has been gaining prominence among these foods is the Euterpe oleracea Mart. (açaí), because it presents in its composition significant amounts of a subclass of the flavonoids, the anthocyanins. METHODS: In the case review, the authors receive a basic background on the most common NDDs, oxidative stress and antioxidants. In addition, revisiting the various studies related to NDDs, including flavonoids and consumption of açaí. RESULTS: Detailed analysis of the recently reported case studies reveal that dietary consumption of flavonoid-rich foods, such as açaí fruits, suggests the efficacy to attenuate neurodegeneration and prevent or reverse the age-dependent deterioration of cognitive function. CONCLUSION: This systematic review points out that flavonoids presenting in açaí have the potential for the treatment of diseases such as PD and AD and are candidates for drugs in future clinical research. However, there is a need for in vitro and in vivo studies with polyphenol that prove and ratify the therapeutic potential of this fruit for several NDDs.


Assuntos
Antioxidantes/uso terapêutico , Euterpe , Flavonoides/uso terapêutico , Doenças Neurodegenerativas/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Humanos , Doenças Neurodegenerativas/metabolismo , Estresse Oxidativo/fisiologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Resultado do Tratamento
14.
Microbiol Resour Announc ; 8(20)2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31097501

RESUMO

We present here the draft genome sequences of Leishmania (Leishmania) amazonensis, Leishmania (Leishmania) mexicana, and Leishmania (Leishmania) aethiopica, potential etiological agents of diffuse cutaneous leishmaniasis (DCL). Sequence data were obtained using PacBio and MiSeq platforms. The PacBio assemblies generated using Canu v1.6 are more contiguous than are those in the available data.

15.
Int J Nanomedicine ; 14: 3375-3388, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31123402

RESUMO

Background: Magnetic nanoparticles (MNPs) have been successfully tested for several purposes in medical applications. However, knowledge concerning the effects of nanostructures on elderly organisms is remarkably scarce. Purpose: To fill part of this gap, this work aimed to investigate biocompatibility and bio-distribution aspects of magnetic nanoparticles coated with citrate (NpCit) in both elderly and young healthy mice. Methods: NpCit (2.4 mg iron) was administered intraperitoneally, and its toxicity was evaluated for 28 days through clinical, biochemical, hematological, and histopathological examinations. In addition, its biodistribution was evaluated by spectrometric (inductively coupled plasma optical emission spectrometry) and histological methods. Results: NpCit presented age-dependent effects, inducing very slight and temporary biochemical and hematological changes in young animals. These changes were even weaker than the effects of the aging process, especially those related to the hematological data, tumor necrosis factor alpha, and nitric oxide levels. On the other hand, NpCit showed a distinct set of results in the elderly group, sometimes reinforcing (decrease of lymphocytes and increase of monocytes) and sometimes opposing (erythrocyte parameters and cytokine levels) the aging changes. Leukocyte changes were still observed on the 28th day after treatment in the elderly group. Slight evidence of a decrease in liver and immune functions was detected in elderly mice treated or not treated with NpCit. It was noted that tissue damage or clinical changes related to aging or to the NpCit treatment were not observed. As detected for aging, the pattern of iron biodistribution was significantly different after NpCit administration: extra iron was detected until the 28th day, but in different organs of elderly (liver and kidneys) and young (spleen, liver, and lungs) mice. Conclusion: Taken together, the data show NpCit to be a stable and reasonably biocompatible sample, especially for young mice, and thus appropriate for biomedical applications. The data showed important differences after NpCit treatment related to the animals' age, and this emphasizes the need for further studies in older animals to appropriately extend the benefits of nanotechnology to the elderly population.


Assuntos
Envelhecimento/fisiologia , Ácido Cítrico/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Nanopartículas de Magnetita/química , Animais , Feminino , Ferro/química , Pulmão/efeitos dos fármacos , Nanopartículas de Magnetita/ultraestrutura , Camundongos , Óxido Nítrico/sangue , Especificidade de Órgãos/efeitos dos fármacos , Distribuição Tecidual/efeitos dos fármacos , Fator de Necrose Tumoral alfa/sangue
16.
Ann Noninvasive Electrocardiol ; 24(4): e12644, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30938470

RESUMO

The criteria for left bundle branch block have gained growing interest in the last few years. In this overview, we discuss diagnostic and prognostic aspects of different criteria. It was already shown that stricter criteria, including longer QRS duration and slurring/notching of the QRS, better identify responders to cardiac resynchronization therapy. We also include aspects of ST/T concordance and discordance and vectorcardiography, which could further improve in the fine-tuning of the left bundle branch criteria.

17.
Braz J Phys Ther ; 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30872005

RESUMO

BACKGROUND: There are a limited number of tests for the assessment of shoulder and pelvic girdle stability. Reliable instruments are important to evaluate movement dysfunction at these joints in order to provide more objective parameters. OBJECTIVE: To evaluate the inter-day reliability of the Upper Body Test in young adults. METHODS: A reliability study was carried out with three assessments of the shoulder and pelvic girdle stability within 48-h intervals (Monday, Wednesday, and Friday). The OctoBalance® platform was used to perform the Upper Body Test in 31 active young adults (24.5±8 years). Intraclass Correlation Coefficient (ICC2,2) two-way mixed model, Coefficient of Variation, and Bland-Altman plots were used to verify the reliability of the test. The standard error of measurement (SEM) and the minimum detectable difference (MDD95%) were calculated for clinical applicability. RESULTS: The Intraclass Correlation Coefficient ranged from 0.87 to 0.94 - Featuring a mean difference of 0.89 (95%CI=-0.19-1.97) to left and 0.95 (95%CI=-0.38-2.27) for the right side, with a low variation coefficient (3.31-5.91%) between the second and third days of assessment. There was a statistically significant difference between the first assessment day and the other test sessions. The Bland-Altman analyses revealed low bias with scores within the limits of agreement. Minimum detectable difference scores were between 4.02 and 5.10, and standard error of measurement between 1.75 and 2.72, depending on the movement side. CONCLUSION: The Upper Body Test presented good inter-day reliability for assessing the stability of the shoulder and pelvic girdle in young active healthy adults.

18.
Clin Anat ; 32(4): 585-596, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30786071

RESUMO

A rule of human anatomy is that all structures within the body should be described relative to the so-called "anatomical position." Along with those describing structures such as the skull and liver, those accounting for the components of the heart consistently break this rule, describing the organ as if removed from the body and positioned on its apex, the so-called "Valentine position." Although potentially appropriate to some animal species, this approach produces problems when used in human anatomy, even if the right and left ventricles are only viewed in truly right-sided and left-sided positions when assessed in the Valentine fashion. The names of the ventricles, of course, are never going to change. This is not necessarily the case with other cardiac components. Consider the artery that extends between the ventricles on their diaphragmatic surface. Blockage produces inferior myocardial infarction, which is to be expected, since the vessel is located in inferior and interventricular position. It is incorrect to describe the artery as being posterior and descending. Such infelicities are now the more obvious with the advent of techniques that, in clinical cardiology, show the components of the heart as it lies within the chest. In this review, we have assessed the frequency of use of the Valentine approach in popular textbooks used by students of human anatomy. We show that, using the conduction tissues as a model, this system also being incorrectly described in the majority of the textbooks, the situation can be improved by use of attitudinally appropriate description. Clin. Anat. 32:585-596, 2019. © 2019 Wiley Periodicals, Inc.


Assuntos
Anatomia/educação , Coração/anatomia & histologia , Humanos
19.
Artigo em Inglês | MEDLINE | ID: mdl-30746520

RESUMO

We present here the first draft genome sequence of Leishmania (Viannia) lainsoni strain 216-34, sequenced using PacBio and MiSeq platforms. PacBio contigs were generated from de novo assemblies using CANU version 1.6 and polished using Illumina reads.

20.
Parasitol Res ; 118(5): 1559-1572, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30796516

RESUMO

Congenital toxoplasmosis is a serious health problem that can lead to miscarriage. HTR-8/SVneo is a first trimester extravillous trophoblast, while BeWo is a choriocarcinoma with properties of villous trophoblast cells. In the placenta, iron is taken up from Fe-transferrin through the transferrin receptor being the ion an important nutrient during pregnancy and also for Toxoplasma gondii proliferation. The aim of this study was to evaluate the role of iron in T. gondii proliferation in BeWo and HTR-8/SVneo cells and in human chorionic villous explants. The cells were infected with T. gondii, iron supplemented or deprived by holo-transferrin or deferoxamine, respectively, and parasite proliferation and genes related to iron balance were analyzed. It was verified that the addition of holo-transferrin increased, and DFO decreased the parasite multiplication in both trophoblastic cells, however, in a more expressive manner in HTR-8/SVneo, indicating that the parasite depends on iron storage in trophoblastic cells for its growth. Also, tachyzoites pretread with DFO proliferate normally in trophoblastic cells demonstrating that DFO itself does not interfere with parasite proliferation. Additionally, T. gondii infection induced enhancement in transferrin receptor mRNA expression levels in trophoblastic cells, and the expression was higher in HTR-8/SVneo compared with BeWo. Finally, DFO-treatment was able to reduce the parasite replication in villous explants. Thus, the iron supplementation can be a double-edged sword; in one hand, it could improve the supplement of an essential ion to embryo/fetus development, and on the other hand, could improve the parasite proliferation enhancing the risk of congenital infection.


Assuntos
Ferro/metabolismo , Complicações Infecciosas na Gravidez/parasitologia , Toxoplasma/crescimento & desenvolvimento , Toxoplasma/metabolismo , Toxoplasmose/metabolismo , Trofoblastos/parasitologia , Linhagem Celular Tumoral , Citoplasma/metabolismo , Feminino , Células HeLa , Humanos , Placenta/química , Placenta/parasitologia , Gravidez , RNA Mensageiro/biossíntese
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