Anti-Leishmania compounds can be screened using Leishmania spp. expressing red fluorescence (tdTomato)

The main challenges associated with leishmaniasis chemotherapy are drug toxicity, the possible emergence of resistant parasites, and a limited choice of therapeutic agents. Therefore, new drugs and assays to screen and detect novel active compounds against leishmaniasis are urgently needed. We thus validated Leishmania braziliensis (Lb) and Leishmania infantum (Li) that constitutively express the tandem tomato red fluorescent protein (tdTomato) as a model for large-scale screens of anti-Leishmania compounds. Confocal microscopy of Lb and Li::tdTomato revealed red fluorescence distributed throughout the entire parasite, including the flagellum, and flow cytometry confirmed that the parasites emitted intense fluorescence. We evaluated the infectivity of cloned promastigotes and amastigotes constitutively expressing tdTomato, their growth profiles in THP-1 macrophages, and susceptibility to trivalent antimony, amphotericin, and miltefosine in vitro. The phenotypes of mutant and wild-type parasites were similar, indicating that the constitutive expression of tdTomato did not interfere with the evaluated parameters. We applied our validated model to a repositioning strategy and assessed the susceptibility of the parasites to eight commercially available drugs. We also screened 32 natural plant and fungal extracts and 10 pure substances to reveal new active compounds. The infectivity and Glucantime treatment efficacy of BALB/c mice and golden hamsters infected with Lb and Li::tdTomato mutant lines, respectively, were very similar compared to animals infected with wild-type parasites. Standardizing our methodology would offer more rapid, less expensive, and easier assays to screen of compounds against L. braziliensis and L. infantum in vitro and in vivo. Our method could also enhance the discovery of active compounds for treating leishmaniasis.

Corrigendum: Assessment of the accuracy of 11 different diagnostic tests for the detection of Schistosomiasis mansoni in individuals from a Brazilian area of low endemicity using latent class analysis

[This corrects the article DOI: 10.3389/fmicb.2022.1048457.].

Accuracy of serological tests in diagnosing mucosal leishmaniasis

In this serum panel-based study, we evaluated the accuracy of serological tests originally developed for visceral leishmaniasis (VL), for diagnosis of mucosal leishmaniasis (ML). A total of five tests were evaluated, four of which are registered at the National Agency of Sanitary Surveillance (Agência Nacional de Vigilância Sanitária-ANVISA) (RIDASCREEN® Leishmania Ab from R-Biopharm AG., Leishmania ELISA IgG + IgM from Vircell S.L., IFI Leishmaniose Humana-BioManguinhos, and IT-LEISH® from Bio-Rad Laboratories, Inc.), and the other a direct agglutination test (DAT-LPC) prototype kit developed at Fiocruz. The panel was composed of 40 serum samples from patients with confirmed ML and 20 from patients with mucosal involvement and negative parasitological/molecular tests for leishmaniasis and confirmation of another etiology. All cases were treated from 2009 to 2016 in a referral center for leishmaniasis in Belo Horizonte, Minas Gerais, Brazil (Instituto René Rachou, Fiocruz). Diagnostic accuracy, based on the cut-off point for VL diagnosis, was 86.2% with RIDASCREEN® Leishmania Ab, 73.3% with Leishmania ELISA IgG + IgM, and 66.7% with IFI Leishmaniose Humana, while IT-LEISH® and DAT-LPC had the lowest accuracy (38.3%), despite high specificity (100% and 95%, respectively). New cut-off points defined with sera from ML patients improved accuracy from 86.2 to 89% (p = 0.64) and 73.3 to 88% (p = 0.04) for RIDASCREEN® Leishmania Ab and Leishmania ELISA IgG + IgM, respectively. Moreover, these tests presented greater sensitivity and immunoreactivity in patients with moderate/severe clinical ML forms. The data of this study suggest that ELISA assays can contribute to laboratory diagnosis, especially for patients with moderate or severe mucosal involvement.

Development and evaluation of an indirect ELISA using a multiepitope antigen for the diagnosis of intestinal schistosomiasis

The laboratory diagnosis of intestinal schistosomiasis, carried out by detecting parasite eggs in feces, has low sensitivity when applied to individuals with low parasitic load. Serological tests can be more sensitive for the diagnosis of the disease. Therefore, the objective of this work was to develop and evaluate an ELISA-based immunoenzymatic assay, using a Schistosoma mansoni multiepitope antigen (ELISA IgG anti-SmME). For this, the amino acid sequences of S. mansoni cathepsin B and asparaginyl endopeptidase were submitted to the prediction of B cell epitopes and, together with peptide sequences obtained from earlier works, were used in the construction of a minigene. The multiepitope protein was expressed in Escherichia coli and the performance of the ELISA IgG anti-SmME for schistosomiasis was evaluated using serum samples from 107 individuals either egg positive or negative. In addition, 11 samples from individuals with other helminth infections were included. The ELISA IgG anti-SmME showed a sensitivity of 81.1% and a specificity of 46.1%. Further analysis revealed a 77.2% sensitivity in diagnosis of individuals with egg counts of ≤12 epg (eggs per gram feces) and 87.5% for individuals with 13–99 epg. It is worth mentioning that, to our knowledge, this was the first study using a multiepitope recombinant antigen in an ELISA for diagnosis of intestinal schistosomiasis, which demonstrated promising results in the diagnosis of individuals with low parasitic loads.

A review of serological tests available in Brazil for intestinal schistosomiasis diagnosis

The World Health Organization (WHO) roadmap and recommendations for elimination of schistosomiasis were recently updated. With significant reductions in the prevalence and intensity of schistosomiasis infections worldwide, there is a need for more sensitive diagnostic methods. There are a few remaining transmission hotspots in Brazil, although low endemicity settings comprise most of the endemic localities. For the latter, serology may represent a tool for population screening which could help eliminate transmission of schistosomiasis. Here, we review serology tests currently available in Brazil from both public health and private laboratories: immunofluorescent antibody tests (IFATs) on adult worm sections and enzyme-linked immunosorbent assays (ELISAs) with soluble egg and adult worm antigens. Both in-house and commercially available tests have received less than adequate performance evaluations. Our review of immediate basic and operational research goals may help identify local adjustments that can be made to improve control interventions aimed at elimination of schistosomiasis as a public health problem.

Assessment of the accuracy of 11 different diagnostic tests for the detection of Schistosomiasis mansoni in individuals from a Brazilian area of low endemicity using latent class analysis

Background

Schistosomiasis is a parasitic disease associated with poverty. It is estimated that 7.1 million people are infected with Schistosoma mansoni in Latin America, with 95% of them living in Brazil. Accurate diagnosis and timely treatment are important measures to control and eliminate schistosomiasis, but diagnostic improvements are needed to detect infections, especially in areas of low endemicity.

Methodology

This research aimed to evaluate the performance of 11 diagnostic tests using latent class analysis (LCA). A cross-sectional survey was undertaken in a low endemicity area of the municipality of Malacacheta, Minas Gerais, Brazil. Feces, urine, and blood samples were collected from 400 residents older than 6 years of age, who had not been treated with praziquantel in the 12 months previous to the collection of their samples. The collected samples were examined using parasitological (Helm Test® kit Kato-Katz), nucleic acid amplification tests -NAATs (PCR, qPCR and LAMP on urine; PCR-ELISA, qPCR and LAMP on stool), and immunological (POC-CCA, the commercial anti-Schistosoma mansoni IgG ELISA kit from Euroimmun, and two in-house ELISA assays using either the recombinant antigen PPE or the synthetic peptide Smp150390.1) tests.

Results

The positivity rate of the 11 tests evaluated ranged from 5% (qPCR on urine) to 40.8% (commercial ELISA kit). The estimated prevalence of schistosomiasis was 12% (95% CI: 9-15%) according to the LCA. Among all tests assessed, the commercial ELISA kit had the highest estimated sensitivity (100%), while the Kato-Katz had the highest estimated specificity (99%). Based on the accuracy measures observed, we proposed three 2-step diagnostic approaches for the active search of infected people in endemic settings. The approaches proposed consist of combinations of commercial ELISA kit and NAATs tests performed on stool. All the approaches had higher sensitivity and specificity than the mean values observed for the 11 tests (70.4 and 89.5%, respectively).

Conclusion

We showed that it is possible to achieve high specificity and sensitivity rates with lower costs by combining serological and NAATs tests, which would assist in the decision-making process for appropriate allocation of public funding aiming to achieve the WHO target of eliminating schistosomiasis as a public health problem by 2030.

Characterization of agglutinating antibodies detected by the direct agglutination test for visceral leishmaniasis diagnosis

This study aimed to characterize agglutinating antibodies detected by the direct agglutination test (DAT-LPC) for the diagnosis of visceral leishmaniasis (VL). The DAT-LPC antigen/antibodies complex was recovered, washed, and used as antigenic substrate in a modified enzyme-linked immunosorbent assay (modified ELISA), revealed with anti-human IgM, IgG, and IgG subtype conjugates, and in the immunofluorescent antibodies test (IFAT), revealed with anti-human IgG and IgG1 conjugates. IgM antibodies were detected in 50%, IgG and IgG1 in 100%, and IgG3 in 52.8% of the 36 samples from VL patients. IFAT showed that agglutinating IgG and IgG1 antibodies recognized more intensely antigens located in the membrane and kinetoplast of the parasite. No antibodies were detected in the 15 samples from healthy individuals. This study shows for the first time that the antibodies responsible for agglutination in DAT-LPC are mostly of the IgG1 subtype.

Pamidronate, a promising repositioning drug to treat leishmaniasis, displays antileishmanial and immunomodulatory potential

Visceral leishmaniasis (VL) is an infectious disease caused by Leishmania infantum (L. infantum). Currently, there are no vaccines and/or prophylactic therapies against VL, and the recentpharmacological approaches come from the drug repositioning strategy. Here, we evaluated the anticancer drug pamidronate (PAM) to identify a new therapeutic option for the treatment of human VL. We assessed its in vitro antileishmanial activity against the promastigote and amastigote forms of L. infantum by evaluating cell cytotoxicity. The antileishmanial and immunomodulatory activities were assessed using human peripheral blood leukocytes ex vivo. PAM induced the formation of vacuoles in the cytoplasm of the promastigotes and alterations in the morphology of the kinetoplast and mitochondria in vitro, which indicates anti-promastigote activity. PAM also reduced the number of infected macrophages and intracellular amastigotes in a concentration-dependent manner, with cell viability above 70%. In ex vivo, PAM reduced the internalized forms of L. infantum in the classical monocyte subpopulation. Furthermore, it enhanced IL-12 and decreased IL-10 and TGF-β by monocytes and neutrophils. Increased IFN-γ and TNF levels for CD8^- and CD8⁺ T lymphocytes and B lymphocytes, respectively, were observed after the treatment with PAM, as well as a reduction in IL-10 by the lymphocyte subpopulations evaluated. Taken together, our results suggest that PAM may be eligible as a potential therapeutic alternative for drug repurposing to treat human visceral leishmaniasis.

Anti-mitochondrial Tryparedoxin Peroxidase Monoclonal Antibody-Based Immunohistochemistry for Diagnosis of Cutaneous Leishmaniasis

Cutaneous leishmaniasis (CL) remains a globally spreading public health problem. Among Latin America countries, Brazil has the greatest number of recorded CL cases with several Leishmania species being associated with human cases. Laboratory diagnosis is one of the major challenges to disease control due to the low accuracy of parasitological techniques, the restricted use of molecular techniques, and the importance of differential diagnosis with regard to several dermatological and systemic diseases. In response, we have developed and validated an immunohistochemistry (IHC) technique for CL diagnosis using anti-mTXNPx monoclonal antibody (mAb). Recombinant Leishmania–mTXNPx was produced and used as an immunogen for mAb production through the somatic hybridization technique. The viability of mAb labeling of Leishmania amastigotes was tested by IHC performed with skin biopsies from hamsters experimentally infected with Leishmania amazonensis, Leishmania braziliensis, and Leishmania guyanensis. The enzymes horseradish peroxidase (IHC-HRP) and alkaline phosphatase (IHC-AP), both biotin-free polymer detection systems, were used in the standardization step. The IHC was further validated with skin biopsies from 49 CL patients diagnosed by clinical examination and quantitative real-time polymerase chain reaction and from 37 patients presenting other dermatological infectious diseases. Other parasitological techniques, such as direct examination and culture, were also performed for confirmed CL patients. Histopathology and IHC were performed for all included patients. Overall, the highest sensitivity was observed for IHC-AP (85.7%), followed by IHC-HRP (79.6%), direct examination (77.6%), histopathological examination (HE; 65.3%), and in vitro culture (49%). Only IHC and HE presented specificity over 90% and were able to detect CL patients regardless of parasite burden (odds ratio > 1.94; 95%CI: 0.34–11.23). A significant increase in positivity rates was observed when IHC-AP was combined with direct examination (95.9%) and HE (93.9%). The IHC techniques evaluated in here detected the main Leishmania species causing CL in Brazil and can support diagnostic strategies for controlling this neglected disease, especially if used in combination with other approaches for an integrative laboratorial diagnosis.

Using data from a private provider of telemedicine to assess the severity of the early 2021 Covid-19 wave in Brazil

In early 2021, Brazil saw a dramatic recurrence in Covid-19 cases associated to the spread of a novel variant of the SARS-CoV-2 virus, the P1 variant. In light of previous reports showing that this variant is more transmissible and more likely to infect people who had recovered from previous infection, a retrospective analysis was conducted to assess if the early 2021 Covid-19 wave in Brazil was associated with an increase in the number of individuals presenting with a more severe clinical course. Fifty-one thousand and fourteen individuals who underwent telemedicine consultations were divided into two groups: patients seen on or before January 31, 2021, and on or after February 1, 2021. These dates were chosen based on the spread of the P1 variant in Brazil. Referral to the emergency department (ED) was used as a marker of a more severe course of the disease. No differences were seen in the proportion of patients referred to the ED in each group nor in the odds ratio of being referred to the ED from the 1st of February 2021 (OR=0.909; 95%CI: 0.81-1.01). Considering the entire cohort, age had an impact on the odds of being referred to the ED, with individuals older than 59 years showing twice the risk of the remaining population and those less than 19 years showing a lower risk.

Changes in gut-brain axis parameters in adult rats of both sexes with different feeding pattern that were early nicotine-exposed

Nicotine is an endocrine disruptor and imprinting factor during breastfeeding that can cause food intake imbalance in the adulthood. As nicotine affects the intestinal microbiota, altering the composition of the bacterial communities and short-chain fatty acids (SCFAs) synthesis in a sex-dependent manner, we hypothesized that nicotine could program the gut-brain axis, consequently modifying the eating pattern of adult male and female rats in a model of maternal nicotine exposure (MNE) during breastfeeding. Lactating Wistar rat dams received minipumps that release 6 mg/kg/day of nicotine (MNE group) or saline for 14 days. The progeny received standard diet from weaning until euthanasia (26 weeks of age). We measured: in vivo electrical activity of the vagus nerve; c-Fos expression in the nucleus tractus solitarius, gastrointestinal peptides receptors, intestinal brain-derived neurotrophic factor (BDNF), SCFAs and microbiota. MNE females showed hyperphagia despite normal adiposity, while MNE males had unchanged food intake, despite obesity. Adult MNE offspring showed decreased Bacteroidetes and increased Firmicutes, Actinobacteria and Proteobacteria. MNE females had lower fecal acetate while MNE males showed higher vagus nerve activity. In summary nicotine exposure through the milk induces long-term intestinal dysbiosis, which may affect eating patterns of adult offspring in a sex-dependent manner.

Virtual fractional flow reserve derived from coronary angiography – artery and lesion specific correlations

Introduction

Virtual Fractional flow reserve (vFFR) from standard non-hyperaemic invasive coronary angiography (ICA) has emerged as a promising non-invasive test to assess hemodynamic severity of coronary artery disease (CAD).

Purpose

To investigate the difference in vFFR analysis between vessels and specific lesions.

Methods

Retrospective analysis of consecutive patients (pts) who underwent invasive functional assessment (iFA) in a tertiary center between 2019 and 2020. vFFR was calculated using dedicated software (CAAS Workstation 8.4) based on coronary angiograms of the acquired in ≥2 different projections, by operators blinded to iFA results. Diagnostic performance of vFFR was evaluated and correlated with iFA, according to coronary vessel, vessel diameter at stenosis, diameter stenosis and area stenosis at lesion. vFFR was considered positive when <0.80. FFR <0.8 and iFR/RFR <0.90 were classified as positive according to current clinical standards.

Results

106 coronary arteries of 95 pts (78% male, mean age 67.8±9.7 years) underwent vFFR evaluation. ICA indications were chronic coronary syndrome in 63% or acute coronary syndrome (non-culprit lesion) in the remaining pts. VFFR accuracy was good (AUC 0.839 (p<0.001) and Pearson's correlation coefficient 0.533 (p<0.001) when vFFR was measured in the distal vessel segment. The correlation improved when vFFR were assessed at lesion site (r=0.631, p<0.001) or up to 1cm below the stenosis (0.610, p<0.001). Binary concordance of 89% were observed in RCA and LAD (Sensibility -S 68%, Specificity-Sp 96%, False positive -FP 3.8%, False negative - FN 31%, predictive positive value-PPV 87%, predictive negative value- PNV 89%), while in the circumflex coronary artery binary concordance were of 77% (S 50%; Sp 82%; FP 18%; FN 50%; PPV 33% and PNV 90%). Correlation between vFFR and iFA was higher in vessels ≥2mm (r=0.730, p<0.001). and in lesions in the extremes of the severity spectrum (Table 1).

Conclusion

vFFR has a moderate to high linear correlation to iFA, depending on the artery and type of lesion studied. The higher correlation was found when vFFR were measured at lesion site, in non-circumflex artery stenosis, in vessels ≥2mm and in vessels with mild or severe stenosis.

Funding Acknowledgement

Type of funding sources: None.

Feasibility of virtual fractional flow reserve derived from coronary angiography and its correlation with invasive functional assessment

Introduction

Invasive functional assessment (iFA) of coronary artery disease (CAD) needs expensive devices, has potential procedure-related complications and is still underutilized. Virtual Fractional Flow Reserve (vFFR) derived from invasive coronary angiography (ICA) has the potential to overcome these limitations.

Purpose

To investigate the feasibility of vFFR analysis and its correlation with iFA (iFR, RFR or FFR).

Methods

Retrospective analysis of consecutive patients (pts) who underwent iFA in a tertiary center between 2019 and 2020. vFFR was calculated using a dedicated software (CAAS Workstation 8.4) based on standard non-hyperaemic coronary angiograms acquired in ≥2 different projections, by operators blinded to iFA results. Diagnostic performance and accuracy of vFFR were evaluated. vFFR was considered positive when <0.80. FFR <0.8 and iFR/RFR <0.90 were classified as positive according to current clinical standards.

Results

Out of 113 coronary arteries of 102 pts, vFFR was successfully analysed in 106 (94%). Reasons for vFFR analysis failure were: vessel projection overlap (48%), <2 angiographic projections (28%) and table movement while acquisition (24%). From 106 coronary arteries of 95 pts with analysable vFFR (78% male, mean age 67.8±9.7 years), 90 (85%) showed agreement with the respective iFA result. The vFFR predicted which lesions were physiologically significant and which were not with accuracy, sensitivity, specificity, positive and negative predictive values of 73%, 73%, 83%, 53%, and 92% respectively. The mean difference between vFFR and iFA were −0.0484±0.096 and Pearson's correlation coefficient was 0.533 (p<0.001). The ROC area under the curve was 0.839 (0.751–0.928, p<0.001).

Conclusion

FFR were feasible in 94% of cases analysed retrospectively. As compared to gold-standard iFA, vFFR had an overall moderate accuracy in detecting ischemia-producing lesions and a negative predictive value >90%. vFFR has the potential to substantially simplify physiological coronary lesion assessment and thus improve its current uptake.

Funding Acknowledgement

Type of funding sources: None. Bland-Altman plot between vFFR and IFA

Headache service quality evaluation: implementation of quality indicators in primary care in Europe

BACKGROUND

Lifting The Burden (LTB) and European Headache Federation (EHF) have developed a set of headache service quality indicators, successfully tested in specialist headache centres. Their intended application includes all levels of care. Here we assess their implementation in primary care.

METHODS

We included 28 primary-care clinics in Germany (4), Turkey (4), Latvia (5) and Portugal (15). To implement the indicators, we interviewed 111 doctors, 92 nurses and medical assistants, 70 secretaries, 27 service managers and 493 patients, using the questionnaires developed by LTB and EHF. In addition, we evaluated 675 patients' records. Enquiries were in nine domains: diagnosis, individualized management, referral pathways, patient education and reassurance, convenience and comfort, patient satisfaction, equity and efficiency of headache care, outcome assessment and safety.

RESULTS

The principal finding was that Implementation proved feasible and practical in primary care. In the process, we identified significant quality deficits. Almost everywhere, histories of headache, especially temporal profiles, were captured and/or assessed inaccurately. A substantial proportion (20%) of patients received non-specific ICD codes such as R51 ("headache") rather than specific headache diagnoses. Headache-related disability and quality of life were not part of routine clinical enquiry. Headache diaries and calendars were not in use. Waiting times were long (e.g., about 60 min in Germany). Nevertheless, most patients (> 85%) expressed satisfaction with their care. Almost all the participating clinics provided equitable and easy access to treatment, and follow-up for most headache patients, without unnecessary barriers.

CONCLUSIONS

The study demonstrated that headache service quality indicators can be used in primary care, proving both practical and fit for purpose. It also uncovered quality deficits leading to suboptimal treatment, often due to a lack of knowledge among the general practitioners. There were failures of process also. These findings signal the need for additional training in headache diagnosis and management in primary care, where most headache patients are necessarily treated. More generally, they underline the importance of headache service quality evaluation in primary care, not only to identify-quality failings but also to guide improvements. This study also demonstrated that patients' satisfaction is not, on its own, a good indicator of service quality.

A Real-Time PCR Assay for the Diagnosis of Intestinal Schistosomiasis and Cure Assessment After the Treatment of Individuals With Low Parasite Burden

The laboratorial diagnosis of the intestinal schistosomiasis is always performed using Kato-Katz technique. However, this technique presents low sensitivity for diagnosis of individuals with low parasite burden, which constitutes the majority in low endemicity Brazilian locations for the disease. The objective of this study was developed and to validate a real-time PCR assay (qPCR) targeting 121 bp sequence to detect Schistosoma spp. DNA for the diagnosis of intestinal schistosomiasis and a sequence of the human β-actin gene as internal control. Firstly, the qPCR was standardized and next it was evaluated for diagnosis and cure assessment of intestinal schistosomiasis in the resident individuals in Tabuas and Estreito de Miralta, two locations in Brazil endemic for intestinal schistosomiasis. The qPCR assay results were compared with those of the Kato-Katz (KK) test, examining 2 or 24 slides, Saline Gradient (SG) and “reference test” (24 KK slides + SG). The cure assessment was measured by these diagnostic techniques at 30, 90, and 180 days post-treatment. In Tabuas, the positivity rates obtained by the qPCR was 30.4% (45/148) and by “reference test” was of 31.0% (46/148), with no statistical difference (p = 0.91). The presumed cure rates at 30, 90, and 180 days post-treatment were 100, 94.4, and 78.4% by the analysis of 24 KK slides, 100, 94.4, and 78.4% by the SG, and 100, 83.3, and 62.1% by the qPCR assay. In Estreito de Miralta, the positivity obtained by qPCR was 18.3% (26/142) and with “reference test” was 24.6% (35/142), with no statistical difference (p = 0.20). The presumed cure rates were 93.3, 96.9, and 96.5% by the KK, 93.3, 96.9, and 100% by the SG, and 93.3, 93.9, and 96.5% by the qPCR at 30, 90, and 180 days post-treatment, respectively. This study showed that the diagnostic techniques presented different performance in the populations from the two districts (Tabuas and Estreito de Miralta) and reinforces the need of combining techniques to improve diagnosis accuracy, increasing the detection of individuals with low parasite burden. This combination of techniques consists an important strategy for controlling the disease transmission.

Feeding aspects of Knodus heteresthes (Eigenmann, 1908) and Moenkhausia lepidura (Kner, 1858) (Characiformes, Characidae) in the Teles Pires and Juruena Rivers, southern Amazon

The composition of the diet of two species of characids (Knodus heteresthes and Moenkhausia lepidura) was evaluated in the Teles Pires and Juruena Rivers, sampled in September and October 2016. We analyzed 226 stomachs of K. heteresthes and 425 of M. lepidura. The analysis of the stomach contents was based on volumetric and frequency of occurrence methods, applying the food importance index. For the similarity of the diets between the species we calculated the niche overlap with Pianka's index. Both species in the Juruena River have a dietary preference for arthropods (IAi > 0.95). In the Teles Pires River the diet is concentrated in three sources for both species: arthropods (IAi > 0.52), vegetables (IAi > 0.33) and fish (IAi > 0.12). The diet was dissimilar when compared to environments (ANOSIM, R ≥ 0.57, p < 0.001) with high trophic niche overlap (α > 0.97), regardless of the sampled environment. In the Teles Pires River, both species were classified as omnivorous with an insectivorous tendency and in the Juruena River the insectivorous behaviour occurs.

Nicotine exposure during lactation causes disruption of hedonic eating behavior and alters dopaminergic system in adult female rats

Tobacco smoke during gestation is associated with increased consumption of palatable foods by the offspring in humans and rats. Postpartum relapse is observed in lactating women who quit smoking during pregnancy, putting their children at risk of adverse health outcomes caused by secondhand smoke. Nicotine is transferred through milk and alters the dopaminergic reward system of adult male rats, reducing dopamine action in the nucleus accumbens (NAc) and hypothalamic arcuate nucleus. Here, we evaluated the long-term effects of nicotine-only exposure during lactation on eating behavior, anxiety, locomotion, dopaminergic system, hypothalamic leptin signaling and nicotinic receptor in the adult female rat progeny. Two days after birth (PN2), Wistar rat dams were separated into control and nicotine (Nic) groups for implantation of osmotic minipumps that released respectively saline or 6 mg/kg nicotine. Lactating dams were kept with 6 pups. After weaning (PN21; nicotine withdrawal), only the female offspring were studied. Euthanasia occurred at PN180. Nic females showed hyperphagia, preference for a high-sucrose diet, increased anxiety-like behavior, lower tyrosine hydroxylase (TH), lower dopamine transporter and higher dopamine receptor (Drd2) in NAc; lower Drd1 in prefrontal cortex and lower TH in dorsal striatum (DS). These animals showed changes that can explain their hyperphagia, such as: lower leptin signaling pathway (Lepr^b, pJAK2, pSTAT3) and Chrna7 expression in hypothalamus. Neonatal nicotine exposure affects the brain reward system of the female progeny differently from males, mainly decreasing dopamine production in NAc and DS. Therefore, Nic females are more susceptible to develop food addiction and obesity.

The heterologous expression of Escherichia coli MutT enzyme is involved in the protection against oxidative stress in Leishmania braziliensis

BACKGROUND Oxidative stress is responsible for generating DNA lesions and the 8-oxoguanine (8-oxoG) is the most commonly lesion found in DNA damage. When this base is incorporated during DNA replication, it could generate double-strand DNA breaks and cellular death. MutT enzyme hydrolyzes the 8-oxoG from the nucleotide pool, preventing its incorporation during DNA replication. OBJECTIVES To investigate the importance of 8-oxoG in Leishmania infantum and L. braziliensis, in this study we analysed the impact of heterologous expression of Escherichia coli MutT (EcMutT) enzyme in drug-resistance phenotype and defense against oxidative stress. METHODS Comparative analysis of L. braziliensis and L. infantum H2O2 tolerance and cell cycle profile were performed. Lines of L. braziliensis and L. infantum expressing EcMutT were generated and evaluated using susceptibility tests to H2O2 and SbIII, cell cycle analysis, γH2A western blotting, and BrdU native detection assay. FINDINGS Comparative analysis of tolerance to oxidative stress generated by H2O2 showed that L. infantum is more tolerant to exogenous H2O2 than L. braziliensis. In addition, cell cycle analysis showed that L. infantum, after treatment with H2O2, remains in G1 phase, returning to its normal growth rate after 72 h. In contrast, after treatment with H2O2, L. braziliensis parasites continue to move to the next stages of the cell cycle. Expression of the E. coli MutT gene in L. braziliensis and L. infantum does not interfere in parasite growth or in susceptibility to SbIII. Interestingly, we observed that L. braziliensis EcMutT-expressing clones were more tolerant to H2O2 treatment, presented lower activation of γH2A, a biomarker of genotoxic stress, and lower replication stress than its parental non-transfected parasites. In contrast, the EcMutT is not involved in protection against oxidative stress generated by H2O2 in L. infantum. MAIN CONCLUSIONS Our results showed that 8-oxoG clearance in L. braziliensis is important to avoid misincorporation during DNA replication after oxidative stress generated by H2O2.

0804 Sleep Bruxism, Awake Bruxism and Sleep Related Breathing Disorders in Adults With Down Syndrome

Introduction

To our knowledge, no studies have accessed theawake bruxism (AB) and stage by stage sleep bruxism (SB) in adults with Down syndrome. Recent works have shown that portable PSG systems are accurate for SB assessment even in the absence of audio-video recording. We aimed to evaluate the prevalence of awake bruxism, stage-by-stage sleep bruxism and Sleep Related Breathing Disorders (SRBD) in adults with Down syndrome.

Methods

Twenty-three adults with Down Syndrome (DS) were enrolled in this study. General health, dental status, parafunctional habits and temporomandibular symptoms were assessed. The history of SB/AB was taken from a questionnaire to the caregivers. A portable PSG type II system (Embla Embletta MPR+PG ST+Proxy, Natus, California-USA) was used to perform a full-sleep study at patients’ home. RMMA activity was defined as low (&gt;1 and &lt;2 episodes/h of sleep), moderate (&gt;2 and &lt;4 episodes/h of sleep), or high (&gt;4 episodes/h of sleep). PSG diagnose of SB was assumed if RMMA index was &gt;2 episodes/h of sleep.

Results

According to caregiver’s report, AB was present in all patients whereas only 13.1% had SB. PSG records showed a SB prevalence of 91.3%, with a mean RMMA index 40.0±30.0/h. Only 2 (8,7%) showed RMMA index of 0.0/h. SB episodes were predominant in N3 and REM sleep stage in 14 and 9 patients, respectively. All but one (95,7%) patient (isolated snoring) presented with OSA (AHI=32.8±28.6). A unique TMD symptom (pain on palpation) was present in 8,7% of the global sample.

Conclusion

The high prevalence of “definitive SB” together with the high prevalence of OSA and snoring point in favor to the recommendation of routine PSG in adults with DS. Furthermore, the low sensitivity of parent-oriented questionnaires reinforces the need of more accurate assessment tools in order to get a better standard of care in this particular group of patients.

Support

State of Sao Paulo Research Support Foundation - FAPESP grant number: 2017/06835-8

0657 Impact of Treatment With Mandibular Advancement Oral Appliance on Respiratory Parameters, Sleep and Cardiometabolic Risk Factors of CPAP Non-Adherent Patients With Severe Obstructive Sleep Apnea

Introduction

Obstructive sleep apnea (OSA) may trigger systemic changes linked to important cardiometabolic risk factors such as hypertension, stroke and diabetes II. As a life-threatening, multifactorial disorder, OSA demands a multiprofessional approach. The most common worldwide treatments are Continuous Positive Airway Pressure (CPAP) and Mandibular Advancement Oral Appliance (OAm). The aim of this study was to evaluate the impact of OAm treatment on CPAP non-adherent patients with severe OSA, comparing objective and subjective data between baseline and follow up.

Methods

A prospective study was carried out including non-adherent severe OSA patients, which were referred to OAm therapy evaluation. Patients presenting with snoring, gasping/choking during sleep, fatigue and daily sleepiness were evaluated by a sleep medicine specialist and the diagnosis of severe OSA with a basal polysomnography (PSG). All the patients were treated with a standard OAm (PMPositioner®). Baseline and Follow up (6 months) sleep parameters (PSG and Epworth Sleepiness Scale - ESS) were compared to assess treatment efficacy.

Results

Seventeen patients (9 with hypertension and 8 with hypertension + diabetes) met the inclusion criteria and 13 finished the protocol. After treatment with OAm the following parameters improved significantly: OSA severity (44.5±13.5 to 9.0±4.3, p≤0.001), ODI (46.8±11.6 to 12.1±9.1(p&lt;0.05)), REM (18.4± 4.8 to 21.5± 2.9 (p&lt;0.05)) and SaO2nadir (75.7± 9.4 to 87.0±3.6, p&lt;0.001), ESS (p&lt;0.005). Ten patients (58%) reported a reduction either in systolic and diastolic blood pressure with 3 of them (30%) reduced the hypertensive drug dose.

Conclusion

Our findings show that OAm is a safe and effective treatment option to CPAP non-adherent severe OSA patients. Furthermore OAm therapy had also a positive impact on cardiometabolic risk factors which are particularly relevant outcomes in OSA patients.

Support

State of Sao Paulo Research Support Foundation (FAPESP).

Leishmania infantum induces high phagocytic capacity and intracellular nitric oxide production by human proinflammatory monocyte

BACKGROUND

The mechanism of resistance to Sb^III in Leishmania is complex, multifactorial and involves not only biochemical mechanisms, but also other elements, such as the immune system of the host.

OBJECTIVES

In this study, putative changes in the immunological profile of human monocytes infected with wild-type (WT) and antimony (Sb^III)-resistant Leishmania (Viannia) braziliensis and Leishmania (Leishmania) infantum lines were evaluated.

METHODS

Susceptibility assays WT and SbIII-resistant L. braziliensis and L. infantum were performed using lines THP-1 human monocytic lineage. Phagocytic capacity, cytokine profile, intracellular nitric oxide (NO) production and surface carbohydrate residues profile were performed in peripheral blood monocytes by flow cytometry.

FINDINGS

The phagocytic capacity and intracellular NO production by classical (CD14⁺⁺CD16^-) and proinflammatory (CD14⁺⁺CD16⁺) monocytes were higher in the presence of L. infantum lines compared to L. braziliensis lines. The results also highlight proinflammatory monocytes as the cellular subpopulation of major relevance in a phagocytosis event and NO expression. It is important to note that L. infantum induced a proinflammatory cytokine profile characterised by higher levels of TNF-α in culture supernatant than L. braziliensis. Conversely, both Leishmania lines induce high levels of IL-6 in culture supernatant. Analysis of the expression profile of surface carbohydrates showed that L. braziliensis presents 4.3-fold higher expression of galactose(β1,4)N-acetylglucosamine than L. infantum line. Interestingly, the expression level of α-N-acetylgalactosamine residues was 2-fold lower in the Sb^III-resistant L. braziliensis line than its counterpart WT line, indicating differences in surface glycoconjugates between these lines.

MAIN CONCLUSIONS

Our results showed that L. braziliensis and L. infantum induce different innate immune responses and a highly inflammatory profile, which is characteristic of infection by L. infantum, the species associated with visceral disease.

Laboratorial algorithm for serological diagnosis of visceral leishmaniasis using rK39-ICT, DAT-LPC and FC-Simplex IgG1

The performance of distinct serological tests (rK39-ICT, IFAT, DAT-LPC, FC-Simplex IgG1) was assessed and a laboratorial algorithm was proposed for accurate diagnosis of VL. DAT-LPC and FC-Simplex IgG1 showed outstanding accuracy (AUC = 0.93) to identify VL patients. The use of a sequential serological algorithm (rK39-ICT screening followed by DAT-LPC or FC-Simplex IgG1) improved the global accuracy for VL (97.2%) diagnosis. An alternative approach for diagnosis of VL has been also assessed for interchangeable use of serum/whole blood lysate samples in DAT-LPC and FC-Simplex IgG1. Our data showed an outstanding agreement for the results obtained with whole blood lysate samples as compared to serum samples (DAT-LPC =100%; FC-Simplex IgG1 = 99%). Together, these findings provide insights to improve the current overall accuracy of VL diagnosis and present innovative laboratorial tests and alternative samples from use in public health services.

Transmission control of schistosomiasis mansoni in a low endemicity area through a single intervention with rigorous prospection of infected cases treated with praziquantel: evaluation after 7 years of intervention

A prospective cohort study with rigorous searching for schistosomiasis cases was conducted among residents of Pedra Preta, Montes Claros, Minas Gerais State, Brazil, seven years after an intervention. Kato-Katz (KK), Saline Gradient, Miracidia Hatch and Polymerase Chain Reaction (PCR) were used as the diagnostic methods in 2008. In the period of 2013-2016, 175 patients remaining in the area were examined using the diagnostic methods Kato-Katz (24 slides, 1 g of feces) and Saline Gradient (2 procedures, 1 g of feces). Sixty-eight out of the 69 infected and treated individuals in 2008 tested negative. The percentage of new cases was 2.29% (4/175), and the 4 infected individuals presented low parasitic load [1, 6, 7 and 19 eggs per gram (EPG)]. All the participants answered epidemiological questionnaires on risky behavior. All residences had pit latrines and domiciliary water supply. The primary transmission focus (lake) was dry for several months. Malacological surveys showed a few non-infected specimens of Biomphalaria glabrata . A clear dominance of Biomphalaria straminea was observed. It can be inferred that a significant decrease in the disease transmission occurred after a single action through an intense search for infected and treated cases under the ecoepidemiological conditions of this area.

Novel ultrastructural findings in bovine oocytes matured in vitro

The ultrastructural morphology of the bovine oocyte at different maturation stages has been previously analyzed but without detailed structural observations at the mature stage. The objective of the present study was thus to establish the ultrastructural characteristics of the mature bovine oocyte in full detail. Oocytes from Bos taurus (Holstein-Friesian) cows were aspirated from ovaries collected after being slaughtered at a local abattoir. After in vitro culture for 24 h, some of them were processed for electron microscopy. We described the ultrastructure of the zona pellucida, which presented three different regions, and novel cytoplasmic findings. There were two types of electron-lucent vesicles (heterogeneous and striated), which were suggested to give rise to lipid droplets, and presence of receptor-mediated endocytosis. In conclusion, our results indicate that although the mature bovine oocyte is devoid of evident yolk, it might be filled with an extensive lipid factory. In addition, even before fertilization, the mature oocyte seemed to absorb nutrients through receptor-mediated endocytosis, indicating active energy use or storage.

Development of a natural molluscicide prototype kit (MoluSchall) for the control of schistosomiasis mansoni transmission

INTRODUCTION

In Brazil, Biomphalaria glabrata, B. tenagophila, and B. straminea are intermediate hosts of Schistosoma mansoni, the etiological agent of schistosomiasis mansoni. Molluscicide use is recommended by the WHO for controlling the transmission of this parasite. Euphorbia milii latex has shown promising results as an alternative molluscicide. Thus, a natural molluscicide prototype kit based on freeze-dried E. milii latex was developed and evaluated against Biomphalaria spp.

METHODS

E. milii latex was collected, processed, and lyophilized. Two diluents were defined for freeze-dried latex rehydration, and a prototype kit, called MoluSchall, was produced. A stability test was conducted using prototype kits stored at different temperatures, and a toxicity assay was performed using Danio rerio. Additionally, MoluSchall was tested against B. glabrata under semi-natural conditions according to defined conditions in the laboratory.

RESULTS

MoluSchall was lethal to three Brazilian snail species while exhibiting low toxicity to D. rerio. Regardless of storage temperature, MoluSchall was stable for 24 months and was effective against B. glabrata under semi-natural conditions, with the same LD100 as observed under laboratory conditions.

CONCLUSIONS

MoluSchall is a natural, effective, and inexpensive molluscicide with lower environmental toxicity than existing molluscicides. Its production offers a possible alternative strategy for controlling S. mansoni transmission.

Hypothalamic Neuropeptides Expression and Hypothalamic Inflammation in Adult Rats that Were Exposed to Tobacco Smoke during Breastfeeding: Sex-Related Differences

The hypothalamus controls food intake and energy expenditure. In rats, maternal exposure to nicotine during breastfeeding alters the hypothalamic circuitry of the adult offspring, resulting in leptin resistance, neuropeptides changes and gliosis. Tobacco smoke exposure during lactation causes greater adiposity, hyperphagia and hyperleptinemia in the adult progeny. To understand the central mechanisms underlying the obese phenotype of adult rats that were directly and indirectly exposed to cigarette smoke during lactation, we investigated leptin signaling, orexigenic and anorexigenic neuropeptides expression, as well as astrocyte and microglia markers in hypothalamus. From postnatal day (PND) 3 to 21, Wistar lactating rat dams and their pups were divided into two groups: SE, smoke-exposed in a cigarette-smoking machine (four times/day); Crtl, exposed to filtered air. Offspring of both sexes were euthanized at PND180. The leptin pathway was not altered in SE animals from both sexes. SE males showed increased NPY (arcuate nucleus, ARC), CRH (paraventricular nucleus, PVN), as well as higher GFAP fiber density (ARC and PVN) and IL6 protein content. TRH (PVN) immunohistochemistry was reduced. SE females had lower CART-positive cells (ARC) and lower α-MSH immunostaining intensity (PVN and lateral hypothalamus), with no change of GFAP or IL-6. The protein contents of CX3CR1 (marker of activated microglia) and α7nAChR (anti-inflammatory marker) were not altered in both SE males and females. Neonatal cigarette smoke is deleterious to the hypothalamic circuitry, inducing changes in energy homeostasis favoring hyperphagia and decreased energy expenditure at adulthood in both sexes; however sex-dependent mechanisms were observed.

P3747Does pulmonary vein isolation have similar results for treating AF in Chagas disease?

Background

AF is reported in up to 20% of patients with Chagas, a prevalent disease in Latin-America. PV isolation (PVI) in the cornerstone of AF ablation. However, in Chagas cardiopathy (ChC), microvascular and autonomic abnormalities, atrial fibrosis and sinoatrial dysfunction are possible mechanisms of AF. Therefore, the results of PVI may be different in this subgroup.

Objectives

To describe long-term results of AF ablation in pts with Chagas versus non-Chagas disease (ChC x NonCh) and evaluate risk factors for post-ablation recurrence.

Methods

This is a prospective, single-center study that included pts with nonvalvular AF who underwent PVI between 2013 and 2016. All procedures were guided by eletroanatomic mapping and intracardiac echocardiogram. Categorical variables were analyzed using chi-square test and numerical variables with t-student test. Binary logistic regression was performed to identify independent predictors of recurrence of any sustained atrial tachyarrhythmias.

Results

Ablation was performed in 160 pts (54±15 yo, 59% male): 42 pts with ChC (26%, 62±8 yo) and 118 NonChC (74%, 53±15 yo; p<0,001)). There was no difference in AF type (38x34% paroxysmal, 42x43% persistent, and 19x23% long-term persistent, p=NS) and left atrium diameter (38±5 vs 40±8mm, p=NS). In ChC the mean CHADSVASC score was higher (2.4 vs 1.4, p<0,001) and LVEF was lower (52±18% vs 64±8%, p=0.02). After a follow-up of 31±14 mo and 1.1 ablation per group, recurrence of AF/AT was higher in ChC (33% vs 14%, p=0.03) although more pts with Chagas were on AAD (71 vs 31%, p<0,001). During follow-up, occurrence of embolic events and cardiac or all-cause mortality were not different between groups (0% vs 1.7%, p=NS and 2.4 vs 1.7% p=NS; for ChC vs and NonChC, respectively).

At multivariate analysis, long-term persistent AF, hypertension and Chagas disease (HR= 2.21, 3.36 and 3.16, respectively) were independent predictors of recurrence.

Conclusions

Chagas disease is an independent predictor of recurrence after PVI. Further studies should address which strategy is more appropriate to this group of patients.

Early weaning alters the thermogenic capacity of brown adipose tissue in adult male and female rats

PURPOSE

Early weaning (EW) is a risk factor for obesity development. Brown adipose tissue (BAT) hypofunction is related to obesity onset. Here, we evaluated whether sympathetic nervous system (SNS) activity in BAT and the thermogenic function of BAT are decreased in adulthood in obese rats from two EW models.

METHODS

At the time of birth, lactating Wistar rats and their pups (three males and three females) were separated into three groups: the control group, in which pups consumed milk throughout lactation; the non-pharmacological EW (NPEW) group, in which suckling was interrupted with a bandage during the last 3 days of lactation; and the pharmacological EW (PEW) group, in which dams were treated with bromocriptine (0.5 mg/twice a day) 3 days before weaning. The offspring were sacrificed on PN180.

RESULTS

Adult male rats from both EW models exhibited lower BAT SNS activity. Female rats from the PEW group showed a decrease in BAT SNS activity. The protein levels of UCP1 were lower in the NPEW males, while PGC1α levels were lower in both PEW and NPEW males. Both groups of EW females showed reductions in the levels of β3-AR, TRβ1, and PGC1α. The UCP1 protein level was reduced only in the NPEW females. The EW groups of both sexes had lower AMPK protein levels in BAT. In the hypothalamus, only the PEW females showed an increase in AMPK protein levels. In both groups of EW males, adrenal catecholamine was increased and tyrosine hydroxylase was decreased, while in EW females, adrenal catecholamine was decreased.

CONCLUSIONS

Early weaning alters the thermogenic capacity of BAT, which partially contributes to obesity in adulthood, and there are sex-related differences in these alterations.

Characterization of CCDC103 expression profiles: further insights in primary ciliary dyskinesia and in human reproduction

PROPOSE

To study CCDC103 expression profiles and understand how pathogenic variants in CCDC103 affect its expression profile at mRNA and protein level.

METHODS

To increase the knowledge about the CCDC103, we attempted genotype-phenotype correlations in two patients carrying novel homozygous (missense and frameshift) CCDC103 variants. Whole-exome sequencing, quantitative PCR, Western blot, electron microscopy, immunohistochemistry, immunocytochemistry, and immunogold labelling were performed to characterize CCDC103 expression profiles in reproductive and somatic cells.

RESULTS

Our data demonstrate that pathogenic variants in CCDC103 gene negatively affect gene and protein expression in both patients who presented absence of DA on their axonemes. Further, we firstly report that CCDC103 is expressed at different levels in reproductive tissues and somatic cells and described that CCDC103 protein forms oligomers with tissue-specific sizes, which suggests that CCDC103 possibly undergoes post-translational modifications. Moreover, we reported that CCDC103 was restricted to the midpiece of sperm and is present at the cytoplasm of the other cells.

CONCLUSIONS

Overall, our data support the CCDC103 involvement in PCD and suggest that CCDC103 may have different assemblies and roles in cilia and sperm flagella biology that are still unexplored.

Performance of serological tests available in Brazil for the diagnosis of human visceral leishmaniasis

Background

Visceral leishmaniasis (VL) is the most severe form of leishmaniasis and is potentially fatal if not diagnosed and treated. Accurate and timely diagnosis is considered one of the pillars needed for the reduction in disease-related lethality. Brazil is currently one of the three eco-epidemiological hotspots for this disease. Several serological tests are commercially available in this country for VL diagnosis, although information on the performance of these tests is fragmented and insufficient. The aim of this study was to directly compare the performance of six commercial kits: three enzyme-linked immunosorbent assays (ELISAs), two immunofluorescence antibody tests (IFATs), one immunochromatographic test (ICT), besides one ICT, currently not commercially available in Brazil and one in-house direct agglutination test (DAT-LPC), not yet marketed.

Methodology/Principal findings

A panel of 236 stored samples from patients with clinically suspected VL, including 77 HIV-infected patients, was tested. IT-LEISH and DAT-LPC showed the highest accuracy rate among the non-HIV-infected patients, 96.2% [CI95%: 92.8–99.7%] and 95.6% [CI95%: 91.9–99.3%], respectively. For the ELISA tests evaluated, the maximum accuracy was 91.2%, and in the inter HIV-status group analysis, no significant differences were observed. For both IFATs evaluated, the maximum accuracy was 84.3%, and a lower accuracy rate was observed among the HIV-infected patients (p = 0.039) than among the non-HIV-infected patients. The DAT-LPC was the most accurate test in the HIV-infected patients (p≤0.115). In general, no significant difference in accuracy was observed among the VL-suspected patients stratified by age.

Conclusions/Significance

In summary, the differences in the performance of the tests available for VL in Brazil confirm the need for local studies before defining the diagnostic strategy.

Visceral leishmaniasis (VL) is a tropical disease distributed worldwide. In the Americas, Brazil reports about 96% of VL cases, which has been highlighted by the increase in lethality in last years. Accurate VL diagnosis is of utmost importance. Despite this, the performance of some commercial tests currently available in Brazil is unknown, especially for HIV-infected patients. Accordingly, in this study we present a comparative performance analysis of six commercial kits available in Brazil for the diagnosis of VL in non-HIV and HIV-infected patients, besides one immunochromatographic test (ICT) and one in-house direct agglutination test (DAT-LPC) currently not commercially available in Brazil. ICTs and DAT-LPC showed better performance among non-HIV infected patients. Despite the known limitation of serological tests for the diagnosis of patients with HIV, the direct agglutination test was more accurate in this specific group of patients. Our results demonstrate significant differences in the performance of different serological tests and confirm that the use of serology should be qualified with previous information on the performance of the tests.

Improving the reference standard for the diagnosis of canine visceral leishmaniasis: a challenge for current and future tests

BACKGROUND

Studies aimed at validating canine visceral leishmaniasis diagnostic tests present heterogeneous results regarding test accuracy, partly due to divergences in reference standards used and different infection evolution periods in animals.

OBJECTIVE

This study aimed to evaluate the accuracy of the rapid test-dual path platform (TR-DPP) (Biomanguinhos®), EIE-Leishmaniose-Visceral-Canina-Biomanguinhos (EIE-LVC) (Biomanguinhos®), enzyme-linked immunosorbent assay (ELISA) rK39 (in-house), and the direct agglutination test (DAT-Canis) against a reference standard comprising parasitological and molecular techniques.

METHODS

A phase II/III validation study was carried out in sample sera from 123 predominantly asymptomatic dogs living in an area endemic for visceral leishmaniasis.

FINDINGS

Sixty-nine (56.1%) animals were considered infected according to the reference standard. For each test, the sensitivity and specificity, respectively, were as follows: TR-DPP, 21.74% [confidence interval (CI)95% 13.64% to 32.82%] and 92.59% (CI95% 82.45% to 97.08%); EIE-LVC, 11.59% (CI95% 5.9% to 21.25%) and 90.74% (CI95% 80.09% to 95.98%); ELISA rK39, 37.68% (CI95% 27.18% to 49.48%) and 83.33% (CI95% 71.26% to 90.98%); and DAT-Canis, 18.84% (CI95% 11.35% to 29.61%) and 96.30% (CI95% 87.46% to 98.98%).

CONCLUSION

We concluded that improving the sensitivity of serum testing for diagnosing asymptomatic dogs must constitute a priority in the process of developing new diagnostic tests to be used in the visceral leishmaniasis control program in Brazil.

Effectiveness of the Brazilian Visceral Leishmaniasis Surveillance and Control Programme in reducing the prevalence and incidence of Leishmania infantum infection

Background

Control strategies adopted by the Brazilian Visceral Leishmaniasis Surveillance and Control Programme (VLSCP) include identifying and culling seropositive infected dogs, early diagnosis and treatment of human cases, chemical control of the vector and population awareness. This study evaluated the effectiveness of the VLSCP on the prevalence and incidence rates of Leishmania infantum in children residing in areas under different VLSCP intervention times.

Methods

A quasi-experimental epidemiological study with a panel (two cross-sectional) and a concurrent cohort was performed in three areas of Belo Horizonte, southeast Brazil. The first cross-sectional study (I) was carried out with 1875 children, 478 of which were enrolled in the cohort study. In the second cross-sectional study (II), 413 additional children were included, totalizing 891 children. Laboratory diagnosis was performed by ELISA-rK39. Analyses included multilevel logistic and Poisson regression models.

Results

The incidence rates of L. infantum infection were: 14.4% in the area where VLSCP intervention was initiated in 2006 (AI2006); 21.1% in the area where intervention was initiated in 2008 (AI2008); and 11.6% in the area where intervention was initiated in 2010 (AI2010 - control area). A follow-up period of 24 months showed that the persons-time incidence rates in AI2006, AI2008, and AI2010 were: 6.2/100, 10/100, and 5.6/100 persons/24 months, respectively. The final prevalence rates of infection (cross-sectional II - in 2012), compared to the initial rates (cross-sectional I - in 2010), increased 83.7% in AI2006, 74.1% in AI2008, and decreased 5% in AI2010. Analysis of the effectiveness revealed that children residing in AI2008 are more likely to be infected (OR = 1.84; 95% CI: 1.06-3.23) and present a higher risk of infection (IRR = 1.76; 95% CI: 1.05-2.95) compared to those in AI2010. No statistically significant differences were observed in asymptomatic infection (OR and IRR) in AI2006 compared to AI2010.

Conclusions

The VLSCP was not effective at controlling L. infantum infection in areas where interventions had respectively been carried out for six and four years. However, it is unclear what the consequences in terms of human infection and diseases would be in the absence of the VLSCP. Efforts to improve the effectiveness of control measures remain a necessary priority.

Electronic supplementary material

The online version of this article (10.1186/s13071-018-3166-0) contains supplementary material, which is available to authorized users.

Development of a laboratorial platform for diagnosis of schistosomiasis mansoni by PCR-ELISA

Objective

We developed a laboratorial platform to release a commercial platform used in the PCR-ELISA for the molecular diagnosis of schistosomiasis mansoni. On following, PCR-ELISA platform laboratorial was evaluated in 206 feces samples collected of individual living in a Brazilian low endemicity area.

Results

The PCR-ELISA laboratorial platform indicated a prevalence rate of 25.2%, which was higher than the Kato-Katz technique (18.4%) and lower than the commercial platform (30.1%). Considering Kato-Katz technique as the reference, there were 97.4% and 91.1% of relative sensitivity and specificity rates, respectively. The laboratorial platform presented good precision, performance diagnostic, and can be used in replacement to the commercial platform for diagnosis of schistosomiasis by PCR-ELISA.

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3571-7) contains supplementary material, which is available to authorized users.

Neonatal tobacco smoke reduces thermogenesis capacity in brown adipose tissue in adult rats

Maternal smoking is a risk factor for progeny obesity. We have previously shown, in a rat model of neonatal tobacco smoke exposure, a mild increase in food intake and a considerable increase in visceral adiposity in the adult offspring. Males also had secondary hyperthyroidism, while females had only higher T4. Since brown adipose tissue (BAT) hypofunction is related to obesity, here we tested the hypothesis that higher levels of thyroid hormones are not functional in BAT, suggesting a lower metabolic rate. We evaluated autonomic nerve activity in BAT and its function in adult rats that were exposed to tobacco smoke during lactation. At birth, litters were adjusted to 3 male and 3 female pups/litter. From postnatal day (PND) 3 to 21, Wistar lactating rats and their pups were divided into SE group, smoke-exposed in a cigarette smoking machine (4 times/day) and C group, exposed to filtered air. Offspring were sacrificed at PND180. Adult SE rats of both genders had lower interscapular BAT autonomic nervous system activity, with higher BAT mass but no change in morphology. BAT UCP1 and CPT1a protein levels were decreased in the SE groups of both genders. Male SE rats had lower β3-AR, TRα1, and TRβ1 expression while females showed lower PGC1α expression. BAT Dio2 mRNA and hypothalamic POMC and MC4R levels were similar between groups. Hypothalamic pAMPK level was higher in SE males and lower in SE females. Thus, neonatal cigarette smoke exposure induces lower BAT thermogenic capacity, which can be obesogenic at adulthood.

Expression of iron-related proteins in feline and canine mammary gland reveals unexpected accumulation of iron

Dysregulation of cellular iron homeostasis in human breast cancer is reflected by the altered expression of regulatory proteins. The expressions of iron-related proteins in the mammary glands of cats and dogs have not been assessed. We evaluated the expressions of ferritin, ferroportin, hepcidin and transferrin receptor 1 in benign and malignant mammary gland lesions in cats and dogs. Iron deposition was detected using Perls' Prussian blue staining. We found no major differences in the expression of iron-related proteins between benign and malignant mammary gland lesions in either cats or dogs; however, these species exhibited accumulation of iron in benign lesions. Our findings provide an explanation for the absence of higher iron requirements by tumor cells in these animals. Further investigation of local iron homeostasis in cats and dogs and differences in their physiology compared to human breast cancer is required.

Metabolism of broilers subjected to different lairage times at the abattoir and its relationship with broiler meat quality

ABSTRACT An investigation was made into the effects of different lairage times and the position of chicken crates during transport to the slaughterhouse on the biochemical and hematological profile and physical parameters of broilers, such as color and pH of their breast meat. The treatments were defined by the animals slaughtered after 0, 2, 4 and 6 hours of lairage time at the slaughterhouse, transported in crates located in the top and bottom layers of the truck. It was found that increasing the lairage time at the slaughterhouse to over two hours reduced the number of lymphocytes and increased the heterophil/lymphocyte (H/L) ratio and the basophil count in the hemogram. In addition, lactate dehydrogenase (LDH) activity and cholesterol levels increased and plasma triglyceride and glucose levels decreased. The position of the crates in the truck altered the creatine kinase (CK) activity, and the highest enzyme activity was found in birds transported in the top layer of crates in the truck. Furthermore, the long lairage time in the slaughterhouse increased the pH and the value of a* (redness value) and decreased the lightness value of breast fillets. The interaction significant between 4 and 6 hours of lairage time and the position of the crate in the top layer of the truck favored the development of dark, firm, dry (DFD) meat.

Acceptance and potential barriers to effective use of diagnostic tests for visceral leishmaniasis in an urban area in Brazil

INTRODUCTION

Acceptance of the IT LEISH(r) and direct agglutination test- made in the Laboratório de Pesquisas Clínicas (DAT-LPC) by healthcare professionals and patients suspected of visceral leishmaniasis (VL) in Ribeirão das Neves was evaluated.

METHODS

Ninety-two patients and 47 professionals completed three questionnaires.

RESULTS

Eighty-eight (96%) patients considered fingertip blood collection a positive test feature, and 86% (37) and 91% of professionals considered the IT LEISH(r) easy to perform and interpret, respectively. All professionals classified the DAT-LPC as simple and easy.

CONCLUSIONS

Patients and healthcare professionals in Ribeirão das Neves demonstrated a high degree of acceptance of the IT LEISH(r) and DAT-LPC.

Early redox imbalance is associated with liver dysfunction at weaning in overfed rats

Neonatal overfeeding induced by litter size reduction leads to further obesity and other metabolic disorders, such as liver oxidative stress and microsteatosis at adulthood. We hypothesized that overfeeding causes an early redox imbalance at weaning, which could programme the animals to future liver dysfunction. Thus, we studied lipogenesis, adipogenesis, catecholamine status and oxidative balance in weaned overfed pups. To induce early overfeeding, litters were adjusted to three pups at the 3rd day of lactation (SL group). The control group contained 10 pups per litter until weaning (NL group). Peripheral autonomic nerve function was determined in vivo at 21 days old. Thereafter, pups were killed for further analysis. Differences were considered significant when P < 0.05. The SL pups presented with a higher visceral adipocyte area, higher content of lipogenic enzymes (ACC, FAS) and with a lower content of adipogenic factors (CEBP, PPARγ) in visceral adipose tissue (VAT). Although autonomic nerve activity and adrenal catecholamine production were not significantly altered, catecholamine receptor (β3ADR) content was lower in VAT. The SL pups also presented with higher triglyceride, PPARγ, PPARα and PGC1α contents in liver. In plasma and liver, the SL pups showed an oxidative imbalance, with higher lipid peroxidation and protein oxidation. The SL group presented with a higher serum alanine aminotransferase (ALT). The early increase in lipogenesis in adipose tissue and liver in weaned overfed rats suggests that the higher oxidative stress and lower catecholamine content in VAT are associated with the early development of liver dysfunction and adipocyte hypertrophy.

Calcium reduces vitamin D and glucocorticoid receptors in the visceral fat of obese male rats

Rats overfed during lactation show higher visceral adipose tissue (VAT) mass and metabolic dysfunctions at adulthood. As both vitamin D and glucocorticoids change adipogenesis, parameters related to metabolism and action of these hormones in the adipocyte can be altered in rats raised in small litters (SL). We also studied the antiobesity effects of high calcium diet since it decreases visceral fat in obesity models. On postnatal day (PN) 3, litter size was adjusted to 3pups/dam (SL) to induce overfeeding. Control litters (NL) remained with 10pups/dam until weaning. From PN120 to PN180, half of the SL rats were fed standard chow (SL) and the other half was fed a calcium-supplemented chow (SL-Ca, 10g CaCO3/kg). Both SL groups were heavier and hyperphagic when compared with the NL group; however, SL-Ca rats ate less than SL. SL-Ca rats had decreased VAT mass and adipocyte size, associated with lower hypothalamic NPY content, VAT fat acid synthase content and leptinemia. At PN120, SL rats had increased plasma 25(OH)D3, Cyp27b1 mRNA and glucocorticoid receptor (GR-α) in the VAT, but lower vitamin D receptor (Vdr) mRNA. At PN180, Cyp27b1 and GR-α remained higher, while Vdr normalized in SL rats. SL-Ca rats had normal VAT Cyp27b1 and GR-α, but lower Vdr Thus, higher body mass and glucocorticoid receptors in the VAT of SL rats are normalized by calcium-enriched diet, and Vdr expression in this tissue is reduced, suggesting a possible role of glucocorticoids and vitamin D in calcium action in the adipocyte.