Anthelmintic Effect of Cannabidiol against Echinococcus granulosus sensu stricto.

Cystic echinococcosis is a global parasitic zoonosis caused by infection with the larval stage of Echinococcus granulosus sensu lato. Cystic echinococcosis affects more than 1 million people worldwide, causing important economic costs in terms of management and livestock associated losses. Albendazole is the main drug used in treating human cystic echinococcosis. In spite of this, its low aqueous solubility, poor absorption, and consequently erratic bioavailability are the cause of its chemotherapeutic failures. Based on the described problem, new treatment alternatives urgently need to be developed. The aim of the present research was to study the in vitro and in vivo efficacy of cannabidiol (CBD), the second most abundant component of the Cannabis sativa plant, was demonstrated against E. granulosus sensu stricto. CBD (50 µg/mL) caused a decrease in protoscoleces viability of 80 % after 24 h of treatment which was consistent with the observed tegumental alterations. Detachment of the germinal layer was observed in 50 ± 10% of cysts treated with 50 µg/mL of CBD during 24 h. In the clinical efficacy study, all treatments reduced the weight of cysts recovered from mice compared with the control group. However, this reduction was only significant with ABZ suspension and the CBD + ABZ combination. As we could observe by the SEM study, the co-administration of CBD with ABZ suspension caused greater ultrastructural alteration of the germinal layer in comparison with that provoked with the monotherapy. Further in vivo research will be conducted by changing the dose and frequency of CBD and CBD + ABZ treatments and new available CBD delivery systems will also be assayed to improve bioavailability in vivo.

Stable and Reusable Fe3 O4 /ZIF-8 Composite for Encapsulation of FDH Enzyme under Mild Conditions Applicable to CO2 Reduction.

The enzymatic reduction of carbon dioxide presents limited applicability due to denaturation and the impossibility of biocatalyst recovery; disadvantages that can be minimized by its immobilization. Here, a recyclable bio-composed system was constructed by in-situ encapsulation under mild conditions using formate dehydrogenase in a ZIF-8 metalorganic framework (MOF) in the presence of magnetite. The partial dissolution of ZIF-8 in the enzyme's operation medium can be relatively inhibited if the concentration of magnetic support used exceeds 10 mg mL-1 . The bio-friendly environment for immobilization does not harm the integrity of the biocatalyst, and the production of formic acid is improved 3.4-fold compared to the free enzyme because the MOFs act as concentrators of the enzymatic cofactor. Furthermore, the bio-composed system retains 86 % of its activity after a long time of five cycles, thus indicating an excellent magnetic recovery and a good reusability.

Carrier recombination and transport dynamics in superstrate solar cells analyzed by modeling the intensity modulated photoresponses.

The dynamics of carrier recombination and transport of two CuInS2 superstrate solar cells was studied by intensity modulated photovoltage and photocurrent spectroscopy (IMVS and IMPS respectively). For the analysis of the resulting data two different approaches were implemented. In the first approach, the typically used analysis in Dye Sensitized Solar Cells (DSSC) was adapted to obtain the characteristic times of the processes involved. The second approach was based on the fittings of both the IMVS and IMPS data to the solution of the continuity equation. These fittings allow the calculation of different dynamic parameters of the cells. Moreover, consistency between the obtained parameters was observed, in good agreement with the typical analysis for DSSC. The resulting dynamics was associated with the presence and distribution of defect states among the samples. Moreover, from the performed analysis, a relation between the results and the post-treatment applied to the solar cells could be established. The difference in the dynamics of the cells is mainly observed in the difference between the electron lifetimes of both solar cells.

Evidence on dye clustering in the sensitization of TiO2 by aluminum phthalocyanine.

As previous studies have shown, the photocatalytic reduction of Cr(VI) to Cr(III) in the presence of 4-chlorophenol can be carried out efficiently under visible irradiation using TiO2 modified with hydroxoaluminum-tricarboxymonoamide phthalocyanine (AlTCPc) in spite of the high aggregation tendency of the dye. In the present work, photocurrent and absorption spectra of AlTCPc modified TiO2 films are studied together with absorption and fluorescence of the dye in solution as a function of the concentration of the dye to clarify (a) the role of aggregates and the nature of the species responsible for electron injection into the semiconductor and (b) the reasons why, as reported earlier, the photocatalytic activity is nearly independent of dye loading at constant TiO2 mass. Results are consistent with the presence of AlTCPc clusters with similar properties both on the TiO2 surface and in H2O-DMSO solution. The actual photoactive species is the monomeric dye electronically coupled to the semiconductor. Monomer concentration depends only slightly on AlTCPc analytical concentration, in a way similar to surfactant monomers in micellar equilibrium, thus explaining the independence of photocatalytic activity on dye concentration.

Photoreduction of Cr(VI) using hydroxoaluminiumtricarboxymonoamide phthalocyanine adsorbed on TiO2.

Hydroxoaluminiumtricarboxymonoamide phthalocyanine (AlTCPc) adsorbed at different loadings on TiO(2) Degussa P-25 was tested for Cr(vi) photocatalytic reduction under visible irradiation in the presence of 4-chlorophenol (4-CP) as sacrificial donor. A rapid reaction takes place in spite of the presumable aggregation of the dye on the TiO(2) surface. The removal of Cr(vi) is fairly negligible under visible-light irradiation, either without photocatalyst or in the presence of bare TiO(2). The fast capture of conduction band electrons by Cr(vi), which forms a surface complex with TiO(2), inhibits the formation of reactive oxygen species in the reductive pathway. This fact and the easier oxidation of 4-CP as compared to AlTCPc hinder the photobleaching of the dye and make feasible Cr(vi) reduction under visible irradiation. The consumption of Cr(vi) follows a pseudo-first order kinetics; the decay constant depends, in the studied range, on the photocatalyst mass, but it is barely affected by dye loading. The presence of 4-CP is essential, but its concentration has no effect on the Cr(vi) decay rate. Oxidation products of 4-CP, such as hydroquinone, catechol or benzoquinone, are not observed. Direct evidence of the one-electron reduction of Cr(vi) to Cr(v) was obtained by EPR spectroscopy using citric acid as Cr(v) trapping agent. In this case, disappearance of Cr(v) also follows a first order decay, but conduction band electrons do not seem to be involved. The fact that oxidation products of 4-CP are not observed is consistent with the fast dark removal of reaction intermediates by Cr(v), proved by EPR.

Electron transfer from photoexcited TiO2 to chelating alizarin molecules: reversible photochromic effect in alizarin@TiO2 under UV irradiation.

Reduction of alizarin molecules coupled to TiO(2) nanoparticles (A@TiO(2)) occurs on UV irradiation in the presence of a sacrificial electron donor. Evidence is presented that reduction is mediated by conduction-band electrons and yields a 1,2,9,10-tetrahydroxyanthracene species which remains coupled to the TiO(2) nanoparticles. The spectrum of the reduced complex displays two overlapping broad bands centred at 480 and 650 nm which can harvest visible photons besides 900 nm, in agreement with theoretical predictions by TDDFT. The potential relevance of the dual-redox behaviour of strongly TiO(2) coupled anthraquinone dyes in the field of photocatalysis and in connection with their utilization in the development of dye-sensitized TiO(2) solar cells is briefly discussed.