The diagnosis of visceral leishmaniasis (VL) has improved with the search of novel antigens; however, their performance is limited when samples from VL/human immunodeficiency virus (HIV)-coinfected patients are tested. In this context, studies conducted to identify more suitable antigens to detect both VL and VL/HIC coinfection cases should be performed. In the current study, phage display was performed using serum samples from healthy subjects and VL, HIV-infected and VL/HIV-coinfected patients; aiming to identify novel phage-exposed epitopes to be evaluated with this diagnostic purpose. Nine non-repetitive and valid sequences were identified, synthetized and tested as peptides in enzyme-linked immunosorbent assay experiments. Results showed that three (Pep2, Pep3 and Pep4) peptides showed excellent performance to diagnose VL and VL/HIV coinfection, with 100% sensitivity and specificity values. The other peptides showed sensitivity varying from 50.9 to 80.0%, as well as specificity ranging from 60.0 to 95.6%. Pep2, Pep3 and Pep4 also showed a potential prognostic effect, since specific serological reactivity was significantly decreased after patient treatment. Bioinformatics assays indicated that Leishmania trypanothione reductase protein was predicted to contain these three conformational epitopes. In conclusion, data suggest that Pep2, Pep3 and Pep4 could be tested for the diagnosis of VL and VL/HIV coinfection.

Evidence suggests that maternal prepregnancy body mass index (BMI) is associated with offspring cardiometabolic risk factors. This study was aimed at assessing the association of maternal prepregnancy BMI with offspring cardiometabolic risk factors in adolescence and adulthood. We also evaluated whether offspring BMI was a mediator in this association. The study included mother–offspring pairs from three Pelotas birth cohorts. Offspring cardiometabolic risk factors were collected in the last follow-up of each cohort [mean age (in years) 30.2, 22.6, 10.9]. Blood pressure was measured using an automatic device, cholesterol by using an enzymatic colorimetric method, and glucose from fingertip blood, using a portable glucose meter. In a pooled analysis of the cohorts, multiple linear regression was used to control for confounding. Mediation analysis was conducted using G-computation formula. In the adjusted model, mean systolic blood pressure of offspring from overweight and obese mothers was on average 1.25 (95% CI: 0.45; 2.05) and 2.13 (95% CI: 0.66; 3.59) mmHg higher than that of offspring from normal-weight mothers; for diastolic blood pressure, the means were 0.80 (95% CI: 0.26; 1.34) and 2.60 (95% CI: 1.62; 3.59) mmHg higher, respectively. Non-HDL cholesterol was positively associated with maternal BMI, whereas blood glucose was not associated. Mediation analyses showed that offspring BMI explained completely the association of maternal prepregnancy BMI with offspring systolic and diastolic blood pressure, and non-HDL cholesterol. Our findings suggest that maternal prepregnancy BMI is positively associated with offspring blood pressure, and blood lipids, and this association is explained by offspring BMI.

There is no suitable vaccine against human visceral leishmaniasis (VL) and available drugs are toxic and/or present high cost. In this context, diagnostic tools should be improved for clinical management and epidemiological evaluation of disease. However, the variable sensitivity and/or specificity of the used antigens are limitations, showing the necessity to identify new molecules to be tested in a more sensitive and specific serology. In the present study, an immunoproteomics approach was performed in Leishmania infantum promastigotes and amastigotes employing sera samples from VL patients. Aiming to avoid undesired cross-reactivity in the serological assays, sera from Chagas disease patients and healthy subjects living in the endemic region of disease were also used in immunoblottings. The most reactive spots for VL samples were selected, and 29 and 21 proteins were identified in the promastigote and amastigote extracts, respectively. Two of them, endonuclease III and GTP-binding protein, were cloned, expressed, purified and tested in ELISA experiments against a large serological panel, and results showed high sensitivity and specificity values for the diagnosis of disease. In conclusion, the identified proteins could be considered in future studies as candidate antigens for the serodiagnosis of human VL.

In the current study, phage-exposed mimotopes as targets against tegumentary leishmaniasis (TL) were selected by means of bio-panning cycles employing sera of TL patients and healthy subjects, besides the immune stimulation of peripheral blood mononuclear cells (PBMCs) collected from untreated and treated TL patients and healthy subjects. The clones were evaluated regarding their specific interferon-γ (IFN-γ) and interleukin-4 (IL-4) production in the in vitro cultures, and selectivity and specificity values were calculated, and those presenting the best results were selected for the in vivo experiments. Two clones, namely A4 and A8, were identified and used in immunization protocols from BALB/c mice to protect against Leishmania amazonensis infection. Results showed a polarized Th1 response generated after vaccination, being based on significantly higher levels of IFN-γ, IL-2, IL-12, tumour necrosis factor-α (TNF-α) and granulocyte-macrophage colony-stimulating factor (GM-CSF); which were associated with lower production of specific IL-4, IL-10 and immunoglobulin G1 (IgG1) antibodies. Vaccinated mice presented significant reductions in the parasite load in the infected tissue and distinct organs, when compared with controls. In conclusion, we presented a strategy to identify new mimotopes able to induce Th1 response in PBMCs from TL patients and healthy subjects, and that were successfully used to protect against L. amazonensis infection.

A study was conducted over eight consecutive days in February 2010 in which daily variations in the vertical distributions of heterotrophic bacteria, mesozooplankton and ichthyoplankton at 1–1200 m in the South-western Atlantic Ocean were investigated. Diurnal and nocturnal samples were collected at an oceanographic station at four regional depths: Tropical Water (TW) (1 m), South Atlantic Central Water (SACW) (250 m), Antarctic Intermediate Water (AAIW) (800 m) and Upper Circumpolar Deep Water (UCDW) (1200 m). Bacterial, mesozooplankton and larval fish densities significantly differed between sample depths but not between sampling tow times. In total, 154 zooplankton species and 18 larval fish species were identified. The highest number of taxa was obtained from the night-time TW trawls. This depth zone had the highest densities of mesozooplankton, larval fish and bacterioplankton (auto and heterotrophic), associated with the highest temperature and salinity and the lowest inorganic nutrient concentrations. Two sample groups were identified based on their mesozooplankton and larval fish compositions: night-time TW and other water masses (daytime TW, SACW, AAIW and UCDW). Thirty-two indicator species were detected in night-time TW. The copepod Nullosetigera impar was, to the best of our knowledge, identified for the first time on the Brazilian coast. Our results showed significant variability in the abundance and vertical distribution of mesozooplankton, bacterioplankton and larval fish along the water column in an oceanic area. We have provided new data and insights on the composition and vertical distribution of mesozooplankton, larval fish and bacterioplankton in deep waters in the South-western Atlantic Ocean.

In the analysis of stability in bifurcation problems it is often assumed that the (appropriate reduced) equations are in normal form. In the presence of symmetry, the truncated normal form is an equivariant polynomial map. Therefore, the determination of invariants and equivariants of the group of symmetries of the problem is an important step. In general, these are hard problems of invariant theory and, in most cases, they are tractable only through symbolic computer programs. Nevertheless, it is desirable to obtain some of the information about invariants and equivariants without actually computing them, for example, the number of linearly independent homogeneous invariants or equivariants of a certain degree. Generating functions for these dimensions are generally known as ‘Molien functions'.

We obtain formulae for the number of linearly independent homogeneous invariants or equivariants for Hopf bifurcation in terms of characters. We also show how to construct Molien functions for invariants and equivariants for Hopf bifurcation. Our results are then applied to the computation of the number of invariants and equivariants for Hopf bifurcation for several finite groups and the continuous group $\mathbb{O}(3)$.

We consider the standard action of the dihedral group $\bf{D}_n$ of order $2n$ on $\bf{C}$. This representation is absolutely irreducible and so the corresponding Hopf bifurcation occurs on $\bf{C} \oplus \bf{C}$. Golubitsky and Stewart (Hopf bifurcation with dihedral group symmetry: Coupled nonlinear oscillators. In: Multiparameter Bifurcation Series, M. Golubitsky and J. Guckenheimer, eds., Contemporary Mathematics 46, Am. Math. Soc., Providence, R.I. 1986, 131–173) and van Gils and Valkering (Hopf bifurcation and symmetry: standing and travelling waves in a circular chain. Japan J. Appl. Math.3, 207–222, 1986) prove the generic existence of three branches of periodic solutions, up to conjugacy, in systems of ordinary differential equations with $\bf{D}_n$-symmetry, depending on one real parameter, that present Hopf bifurcation. These solutions are found by using the Equivariant Hopf Theorem. We prove that generically, when $n\neq 4$ and assuming Birkhoff normal form, these are the only branches of periodic solutions that bifurcate from the trivial solution.