Dual pulsed laser deposition system for the growth of complex materials and heterostructures

Here, we present an integrated ultra-high-vacuum (UHV) apparatus for the growth of complex materials and heterostructures. The specific growth technique is the Pulsed Laser Deposition (PLD) by means of a dual-laser source based on an excimer KrF ultraviolet and solid-state Nd:YAG infra-red lasers. By taking advantage of the two laser sources-both lasers can be independently used within the deposition chambers-a large number of different materials-ranging from oxides to metals, to selenides, and others-can be successfully grown in the form of thin films and heterostructures. All of the samples can be in situ transferred between the deposition chambers and the analysis chambers by using vessels and holders' manipulators. The apparatus also offers the possibility to transfer samples to remote instrumentation under UHV conditions by means of commercially available UHV-suitcases. The dual-PLD operates for in-house research as well as user facility in combination with the Advanced Photo-electric Effect beamline at the Elettra synchrotron radiation facility in Trieste and allows synchrotron-based photo-emission as well as x-ray absorption experiments on pristine films and heterostructures.

Application of Poloxamers for the Development of Drug Delivery System to Treat Leishmaniasis: A Review

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.

Spatial analysis of the prevalence of schistosomiasis in an endemic coastal area in north-eastern Brazil

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.

Human amebiasis: breaking the paradigm?

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.