Parasitic Infection and Immunity—A Special Biomedicines Issue

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The old and new therapeutic approaches to the treatment of giardiasis: Where are we?

Giardia lamblia is the causative agent of giardiasis, one of the most common parasitic infections of the human intestinal tract. This disease most frequently affects children causing abdominal pain, nausea, vomiting, acute or chronic diarrhea, and malabsorption syndrome. In undernourished children, giardiasis is a determining factor in retarded physical and mental development. Antigiardial chemotherapy focuses on the trophozoite stage. Metronidazole and other nitroimidazoles have been used for decades as the therapy of choice against giardiasis. In recent years many other drugs have been proposed for the treatment of giardiasis. Therefore, several synthetic and natural substances have been tested in search of new giardicidal compounds. This study is a review of drugs used in in vitro and in vivo tests, and also drugs tested in clinical trials (nonrandomized and randomized)

Dyeing of PA6.6 fibers - Effect of solvent and temperature on thermal properties

Dyeing fibers at low temperatures has many advantages such as savings in energy and avoiding alterations to the physical properties of the fibers being dyed or other fibers also present in blends, The problem of low temperature dyeing in synthetic fibers is that it difficults the dye diffusion into the fiber. In the case of polyamide 6.6 microfibers, by using benzyl alcohol as an auxiliary dyeing, it was shown that good diffusion was obtained for the dye exhaustion with metal complex dyes at temperatures more than 30°C below the normal dyeing temperature for the dye exhaustion with metal complex dyes. Using thermal analysis methods these results were shown to be caused by the lowering of the T g of the fiber when in the presence of benzyl alcohol.Fundação para a Ciência e a Tecnologia (FCT

Indicadores mineralógicos de drenagem ácida (ARD) em cortes de estrada em diferentes unidades litoestratigráficas

Construction of highways in some particular geological conditions exposes pyrite and other associated sulfides to oxidative weathering. This generates a process known as acid rock drainage. As a consequence, typical properties of acid drainage may develop, such as precipitation of soluble salts efflorescences. Also, acidic and metal-rich runoff from the exposed road cuts may pose concerns about the surface and groundwater contamination as well as regarding the structural robustness and the safety of the road slopes. In the North of Portugal, particularly in the Minho region there are geological conditions that promote the development of natural acidic and metal contamination. Such acid rock drainage appears as an exuberant phenomenon in several highway cuts, where the sulfide-rich exposed rocks are suffering oxidation. The present work reveals the occurrence of acid rock drainage sites in road cuts in the north of Portugal, relating this process with the geology of the terrains. Thus, it describes the sources of acid and metals and the respective genesis conditions, and presents the mineralogical indicators of such a geochemical process, which are dominated by magnesium sulfates. Moreover, remediation measures are pointed out, some of them already implemented in some sites.A construção de infraestruturas viárias em certas condições geológicas pode expor minerais como os sulfuretos a mecanismos de dissolução oxidativa. A complexa cadeia de reacções que se desencadeia gera um processo de drenagem ácida, que na bibliografia anglo-saxónica é conhecida por “Acid Rock Drainage” (ARD). Como consequência, desenvolvem-se propriedades típicas de uma contaminação ácida, idêntica à que se observa em contexto mineiro, tais como a precipitação de sais solúveis. Para além desta manifestação mineralógica, as águas de escorrência criam preocupações ambientais, especificamente no que respeita à qualidade do meio hídrico, mas também quanto à estabilidade dos taludes sujeitos a uma meteorização química acelerada. No Norte de Portugal, particularmente na região do Minho, existem condições geológicas favoráveis ao desenvolvimento deste processo, que se manifesta de forma exuberante nalguns cortes de auto-estrada. O presente trabalho revela a ocorrênca de sítios afectados, relacionando o processo com a geologia dos terrenos em que se implementaram estas vias. Descreve-se a origem da drenagem ácida e apresentam-se indicadores mineralógicos da evolução geoquímica das rochas mais reactivas, dominados pela presença de sulfatos de magnésio. Apontam-se ainda exemplos de medidas de remediação, algumas já implementadas em certos sectores das vias afectadas.This work was co-funded by the EU, based on COMPETE 2020, project ICT (UID/GEO/04683/2013), reference POCI-01-0145-FEDER-007690, national funds provided by FC