13 research outputs found
Plant Health and Rhizosphere Microbiome: Effects of the Bionematicide Aphanocladium album in Tomato Plants Infested by Meloidogyne javanica
The artificial introduction in the soil of antagonistic microorganisms can be a successful strategy, alternative to agrochemicals, for the control of the root-knot nematodes (Meloidogyne spp.) and for preserving plant health. On the other hand, plant roots and the associated rhizosphere constitute a complex system in which the contribution of microbial community is fundamental to plant health and development, since microbes may convert organic and inorganic substances into available plant nutrients. In the present study, the potential nematicidal activity of the biopesticide Aphanocladium album (A. album strain MX-95) against the root-knot nematode Meloidogyne javanica in infected tomato plants was investigated. Specifically, the effect of the A. album treatment on plant fitness was evaluated observing the plant morphological traits and also considering the nematode propagation parameters, the A. album MX-95 vitality and population density. In addition, the treatment effects on the rhizosphere microbiome were analysed by a metabarcoding procedure. Treatments with A. album isolate MX-95 significantly decreased root gall severity index and soil nematode population. The treatment also resulted in increased rhizosphere microbial populations. A. album MX-95 can be favourably considered as a new bionematicide to control M. javanica infestation
Mechanistic Insight into the Inhibition of Matrix Metalloproteinases by Platinum Substrates
Platinum compounds are among the most used DNA-damaging anticancer drugs, however they can
also be tailored to target biological substrates different from DNA, for instance enzymes involved in
cancer progression. We recently reported that some platinum complexes with three labile ligands inhibit
matrix metalloproteinase activity in a selective way. We have now extended the investigation to a series
of platinum complexes having three chlorido or one chlorido and a dimethylmalonato leaving ligands.
All compounds are strong inhibitors ofMMP-3 by a noncompetitive mechanism, while platinum drugs
in clinical use are not. Structural investigations reveal that the platinum substrate only loses two labile
ligands, which are replaced by an imidazole nitrogen of His224 and a hydroxyl group, while it retains one
chlorido ligand. A chlorido and a hydroxyl group are also present in the zinc complex inhibitor of
carboxypeptidase A, whose active site has strong analogies with that of MMP-3
Platinum Complexes Can Inhibit Matrix Metalloproteinase Activity: Platinum-Diethyl[(methylsulfinyl)methyl]phosphonate Complexes as Inhibitors of Matrix Metalloproteinases 2, 3, 9, and 12
Platinum complexes able to inhibit matrix metalloproteinases (MMPs) through a noncompetitive mechanism are reported for the first time in this study. [PtCl2(SMP)] and [Pt(dimethylmalonato)(SMP)], characterized by the bisphosphonate-analogue ligand diethyl[(methylsulfinyl)methyl]phosphonate (SMP), are slight inhibitors of MMP-2 (IC50 = 258 +/- 38 and 123 +/- 14 mu M, respectively) but markedly inhibit MMP-9 (IC50 = 35.5 +/- 6 and 17 +/- 4 mu M), MMP-3 (IC50 = 5.3 +/- 2.9 and 4.4 +/- 2.2 mu M), and MMP-12 (IC50 = 10.8 +/- 3 and 6.2 +/- 1.8 mu M). In contrast, cisplatin, carboplatin, and the SMP ligand are inactive, and the bisphosphonate clodronate shows a broad-spectrum inhibitory activity in the high micromolar range (mean IC50 > 200 mu M). These results, along with mechanistic investigations (DNA interaction and tumor cell growth inhibition), demonstrate that ligand modifications of platinum compounds can be exploited to target also biological substrates distinct from DNA
Efficacy of ivermectin to control Strongyloides stercoralis infection in sheltered dogs
In dogs, information on treatments against S. stercoralis infection is rare and anecdotal. The aim of the present work was to evaluate the treatment outcome of S. stercoralis natural infection in sheltered dogs. Furthermore, based on the potential risk of infection, people working in the infected shelter were also tested. Seventeen sheltered dogs positive to S. stercoralis using the Baermann test were treated with ivermectin 200 ÎĽg/kg/sid/os for two consecutive days. Only two dogs showed clinical signs suggestive of strongyloidiasis (diarrhea, weigh loss) at diagnosis. All dogs showed consistently negative results for S. stercoralis at weekly monitoring after treatment using both the direct microscopy and Baermann test. Real-time PCR confirmed negative results at the last follow up 2 months after treatment. Serology performed at the first diagnosis showed that 82% and 41% of dogs were positive for S. stercoralis using an IFAT (titres ranging from 1:40 to 1:320) and ELISA, respectively. Two months after treatment, IFAT titres were strongly reduced in all animals. The results of clinical pathological laboratory tests at diagnosis in the positive dogs were within normal ranges, except for the two symptomatic dogs. Serum collected from two out of 14 shelter workers tested positive with titres 1:20 and 1:40 for S. stercoralis using an IFAT. Results of the study confirm that ivermectin was an effective treatment option to control S. stercoralis infection in dogs. Shelter workers are at risk of infection with S. stercoralis, thus the application of correct deworming protocols to reduce the environmental infective larval burden is essential to protect dogs and probably also shelter workers from the risk of infection