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We have identified fifty-eight samples that were positive for Dengue-4 among 119 samples with negative diagnoses for dengue via the Platelia™ dengue NS1 Ag in Aracaju, State of Sergipe, Brazil. We determined that the low sensitivity of the NS1 Ag test could be related to secondary dengue infections in the studied population. Therefore, we concluded that the sensitivity and specificity of the Platelia™ dengue NS1 Ag test as a screening method for monitoring circulating dengue serotypes must be reevaluated. In addition, regional endo-epidemic profiles should also be considered due to the prevalence of secondary responses.

Abstract Background Bacillus thuringiensis (Bt) is a widely used biopesticide. The bioinsecticide based on Bt is obtained by fermentation, but the substrates currently used for its production constitute ingredients of high commercial value. In this context, the use of agro-industrial residues as substrates is an alternative to make the fermentation process viable on a large scale, in addition to minimizing environmental problems and contributing to the destination of these residues for biotechnological purposes. Results In the first part of this study, a previously isolated spore forming soil bacteria (Bv5) harboring and expressing a novel cry 8A gene was confirmed as B. thuringiensis based on its morphological characteristics, Gram staining, scanning electron microscopy (SEM) and genome sequencing. Bv5 was established as a Gram-positive spore forming bacteria with ellipsoidal spores and small round toxins. Bv5 genome comprised of the 5.30 Mb chromosome and two megaplasmids of 450 kb and 261 kb, respectively, with cry 8A gene located on the smallest megaplasmid. In the second part of the study, the physiological profile of the Bv5 strain during fermentation in different agro-industrial biowastes (cassava wastewater, orange pulp wash and whey) was analyzed. The fermentation experiment was divided into two stages. In the first stage, the agro-industrial waste with or without salts with the best results for biomass, spores and proteins production was selected. In the second stage, the effect of the selected medium in original and diluted form with the C:N balance was evaluated, in two different fermentation times (72 h and 96 h). Pulp wash enriched with salts was selected as the most suitable medium for the growth of Bv5 strain in the first stage. In the second stage pulp wash (without dilution) with the addition of salts, and with nitrogen supplementation, was considered the best for cell growth, spore and toxin production by Bv5. Conclusions To conclude, our study provide a new alternative for bio-waste from the orange juice industry, as well as potential culture medium for the Bt commercial scale production.

Leishmaniasis is one of the deadliest neglected tropical diseases affecting 12–15 million people worldwide, especially in middle- and low-income countries. Rapid and accurate diagnosis of the disease is important for its adequate management and treatment. Several techniques are available for the diagnosis of leishmaniasis. Among these, parasitological and immunological tests are most widely used. However, in most cases, the utilized diagnostic techniques are not good enough, showing cross-reactivity and reduced accuracy. In recent years, many new methods have been reported with potential for improved diagnosis. This review focuses on the diagnosis of Leishmania exploring the biosensors and nanotechnology-based options for their detection. New developments including the use of nanomaterials as fluorophores, fluorescence quenchers as reducing agents and as dendrimers for signal improvement and amplification, together with the use of aptamers to replace antibodies are described. Future research opportunities to overcome the current limitations on the available diagnostic approaches are also discussed.

The use of lipid nanoparticles as drug delivery systems has been growing over recent decades. Their biodegradable and biocompatible profile, capacity to prevent chemical degradation of loaded drugs/actives and controlled release for several administration routes are some of their advantages. Lipid nanoparticles are of particular interest for the loading of lipophilic compounds, as happens with essential oils. Several interesting properties, e.g., anti-microbial, antitumoral and antioxidant activities, are attributed to carvacrol, a monoterpenoid phenol present in the composition of essential oils of several species, including Origanum vulgare, Thymus vulgaris, Nigellasativa and Origanum majorana. As these essential oils have been proposed as the liquid lipid in the composition of nanostructured lipid carriers (NLCs), we aimed at evaluating the influence of carvacrol on the crystallinity profile of solid lipids commonly in use in the production of NLCs. Different ratios of solid lipid (stearic acid, beeswax or carnauba wax) and carvacrol were prepared, which were then subjected to thermal treatment to mimic the production of NLCs. The obtained binary mixtures were then characterized by thermogravimetry (TG), differential scanning calorimetry (DSC), small angle X-ray scattering (SAXS) and polarized light microscopy (PLM). The increased concentration of monoterpenoid in the mixtures resulted in an increase in the mass loss recorded by TG, together with a shift of the melting point recorded by DSC to lower temperatures, and the decrease in the enthalpy in comparison to the bulk solid lipids. The miscibility of carvacrol with the melted solid lipids was also confirmed by DSC in the tested concentration range. The increase in carvacrol content in the mixtures resulted in a decrease in the crystallinity of the solid bulks, as shown by SAXS and PLM. The decrease in the crystallinity of lipid matrices is postulated as an advantage to increase the loading capacity of these carriers. Carvacrol may thus be further exploited as liquid lipid in the composition of green NLCs for a range of pharmaceutical applications.

The objective of this study was to verify the occurrence of intestinal parasites in 3 to 6-year-old children from daycare centers maintained by the municipal government of Belo Horizonte, Minas Gerais, Brazil. Coproparasitological tests performed in 472 children have shown that 24.6% of them had some type of parasites, 6.6% of the children having more than one type. Among protozoa, Entamoeba coli (14.0%) and G. duodenalis (9.5%) were the most prevalent, whereas Ascaris lumbricoides (3.0%) and Trichuris trichiura (1.1%) were the most frequent among the helminths. Thus, we can observe that intestinal parasites still represent a serious public health problem in Belo Horizonte, especially among children and in areas where the socioeconomic conditions are less favorable.O objetivo deste trabalho foi verificar a ocorrência de parasitos intestinais em crianças de 3 a 6 anos de idade, oriundas de creches mantidas pela Prefeitura Municipal de Belo Horizonte, Minas Gerais, Brasil. Exames coproparasitológicos realizados em 472 crianças demonstraram que 24,6% apresentavam algum tipo de parasitose, sendo que 6,6% apresentavam mais de um parasito. Entre os protozoários, Entamoeba coli (14,0%) e G. duodenalis (9,5%) foram os mais prevalentes, enquanto Ascaris lumbricoides (3,0%) e Trichuris trichiura (1,1%) foram os mais encontrados entre os helmintos. Desta forma, observa-se que as parasitoses intestinais ainda são um problema de saúde pública em Belo Horizonte, principalmente entre a população infantil e em áreas onde as condições sócio-econômicas são menos favoráveis.

BACKGROUND AND AIMS: Rotavirus causes severe diarrhoea and Brazil introduced the Rotarix G1P[8] vaccine in 2006. We aimed to describe changes in rotavirus incidence and diarrhoea epidemiology before and after vaccine introduction. METHODS: DESIGN: (i) hospital-based survey of children with diarrhoea (2006-2012); (ii) diarrhea-mortality and hospitalization surveillance (1999-2012). SETTING: (i) Aracaju and (ii) state and national level. RESULTS: 1841 children were enrolled and 231 (12.5%) had rotavirus. Rotavirus was less frequent from January-June than from July-December (9.4% versus 20.9%, p

Although Entamoeba dispar displays a similar morphology to Entamoeba histolytica, cellular and molecular studies have revealed significant differences between these two amoebae, including the former being characterized as non-pathogenic and the later as pathogenic. However, recent in vivo and in vitro experiments have shown that E. dispar strains of different origin are capable of causing liver damage and destroying cell culture lines in the presence of common intestinal bacteria. These results suggested that E. dispar may present pathogenic behavior according to the specific E. dispar strain, culture and environmental conditions. To investigate this possibility, we carried out in vivo and in vitro studies using a xenic strain E. dispar (ICB-ADO) isolated from a symptomatic non-dysenteric Brazilian patient. This strain was able to induce liver necrosis in a hamster model that was more severe than that produced by E. histolytica. The ICB-ADO isolate also caused significantly more destruction of cultured MDCK cells and increased loss of transepithelial resistance than did the E. histolytica. Xenic E. dispar exhibited high proteolytic activity, which was partially inhibited by the addition of cysteine-protease inhibitors. Based on our biochemical and molecular characterization of E. dispar (ICB-ADO) xenic culture and its ability to produce liver abscesses, we conclude that this specific strain can indeed produce tissue damage, distinct from the frequently used non-pathogenic E. dispar SAW 760 strain.

Leishmaniasis is a neglected tropical disease affecting more than 1.5 million people annually, with an annual mortality of over 20.000. The drugs used for its treatment are toxic, expensive, require extended treatment times and present variable efficacy. The disease severity and therapy limitations suggest the need for new antileishmanial agents. In this context, in order to identify new options for treatment, a number of studies based on nanotechnological strategies have been carried out. Poloxamers are triblock copolymers very often utilized for nanotherapeutic solutions, resulting in products with better solubility, higher stability, superior therapeutic efficacy and less toxicity. This review will discuss the physicochemical properties of the copolymers, as well as describe the use of poloxamers for the development of therapeutic formulations to treat leishmaniasis., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Leishmaniasis are a group of neglected infectious diseases caused by protozoa of the genus Leishmania with distinct presentations. The available leishmaniasis treatment options are either expensive and/or; cause adverse effects and some are ineffective for resistant Leishmania strains. Therefore, molecules derived from natural products as the monoterpene carvacrol, have attracted interest as promising anti-leishmania agents. However, the therapeutic use of carvacrol is limited due to its low aqueous solubility, rapid oxidation and volatilization. Thus, the development of nanostructured lipid carriers (NLCs) was proposed in the present study as a promising nanotechnology strategy to overcome these limitations and enable the use of carvacrol in leishmaniasis therapy. Carvacrol NLCs were obtained using a warm microemulsion method, and evaluated regarding the influence of lipid matrix and components concentration on the NLCs formation. NLCs were characterized by DSC and XRD as well. In addition, to the in vitro carvacrol release from NLCs, the in vitro cytotoxicity and leishmanicidal activity assays, and the in vivo pharmacokinetics evaluation of free and encapsulated carvacrol were performed. NLCs containing carvacrol were obtained successfully using a warm microemulsion dilution method. The NLCs formulation with the lowest particle size (98.42 ± 0.80 nm), narrowest size distribution (suitable for intravenous administration), and the highest encapsulation efficiency was produced by using beeswax as solid lipid (HLB=9) and 5% of lipids and surfactant. The in vitro release of carvacrol from NLCs was fitted to the Korsmeyer and Peppas, and Weibull models, demonstrating that the release mechanism is probably the Fickian diffusion type. Moreover, carvacrol encapsulation in NLCs provided a lower cytotoxicity in comparison to free carvacrol (p<0.05), increasing its in vitro leishmanicidal efficacy in the amastigote form. Finally, the in vivo pharmacokinetics of carvacrol after IV bolus administration suggests that this phenolic monoterpene undergoes enterohepatic circulation and therefore presented a long half-life (t 1/2 ) and low clearance (Cl). In addition, C 0 , mean residence time (MRT) and V dss of encapsulated carvacrol were higher than free carvacrol (p < 0.05), favoring a higher distribution of carvacrol in the target tissues. Thus, it is possible to conclude that the developed NLCs are a promising delivery system for leishmaniasis treatment., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Due to contact and misuse of water drainage channels, schistosomiasis has spread and become a constant concern in northeastern Brazil. The aim of this study was to monitor human cases of Schistosomiasis mansoni and the breeding areas of the snail intermediate host Biomphalaria glabrata through spatial analysis in a community named Invasão do Canal do Guaxinim, located in Barra dos Coqueiros City in an endemic coastal part of the state of Sergipe, Brazil. This research was performed as a cross-sectional epidemiological study conducted with parasitological and malacological surveys. To verify the spatial analysis, a two-year spatial point pattern analysis was performed by means of Kernel intensity estimation using TerraView software 4.2.2. A schistosomiasis prevalence reduction from 8.1% (2013) to 4.9% (2014) was observed but mild infection prevailed in adolescents and/or young adults during the two-year study. In malacological research, 387 specimens of snails of the genus B. glabrata were collected and all were negative with regard to schistosomiasis. Spatial analysis showed a strong, spatial trend of increased transmission risk areas north and south of the community, both in 2013 and 2014. In Invasão do Canal do Guaxinim itself, the increased risk was only seen in the northern part. When combined, the human and the malacological spatial analyses constituted an important methodological approach for monitoring and controlling this parasitic disease.

For over 30 years it has been established that the Entamoeba histolytica protozoan included two biologically and genetically different species, one with a pathogenic phenotype called E. histolytica and the other with a non-pathogenic phenotype called Entamoeba dispar. Both of these amoebae species can infect humans. E. histolytica has been considered as a potential pathogen that can cause serious damage to the large intestine (colitis, dysentery) and other extraintestinal organs, mainly the liver (amebic liver abscess), whereas E. dispar is a species that interacts with humans in a commensal relationship, causing no symptoms or any tissue damage. This paradigm, however, should be reconsidered or re-evaluated. In the present work, we report the detection and genotyping of E. dispar sequences of DNA obtained from patients with amebic liver abscesses, including the genotyping of an isolate obtained from a Brazilian patient with a clinical diagnosis of intestinal amebiasis that was previously characterized as an E. dispar species. The genetic diversity and phylogenetic analysis performed by our group has shown the existence of several different genotypes of E. dispar that can be associated to, or be potentiality responsible for intestinal or liver tissue damage, similar to that observed with E. histolytica.