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991.
J.A. Aguilera Sammaritano C.C. López Lastra A. Leclerque F. Vazquez M.E. Toro C.P. D’Alessandro 《Biocontrol Science and Technology》2016,26(12):1668-1682
Entomopathogenic Hypocreales were isolated from arid soils in Argentina using Tenebrio molitor as bait and tested for their biological performance at 30°C and 45–65% RH. Conidial germination was tested in three vegetable oils (sunflower, olive and maize) at two concentrations (1% and 10%) to evaluate their compatibility for further liquid formulations. According to radial growth and germination results, we selected four isolates to test their pathogenicity against second instar B. tabaci nymphs with the selected oil formulations at 30°C. CEP381 and CEP401 showed the highest radial growth. Isolates CEP381, CEP401, CEP413 and CEP409 (Metarhizium spp.) had similar germination percentages as compared with water control when germinated on either sunflower, olive or maize oils at 10% v/v. The highest mortality of B. tabaci was observed for the isolates CEP381 in sunflower oil and CEP401 in olive oil. Molecular identification of isolates was performed using ITS4–5 primers. All isolates belong to the Metarhizium core group. Tested isolates could grow and infect B. tabaci nymphs at 30°C in some of the vegetable oils as carriers, providing new possibilities for integrated pest management of Bemisia tabaci. 相似文献
992.
Alessandro Pratesi Damiano Cirri Mirjana D. Đurović Serena Pillozzi Giulia Petroni Živadin D. Bugarčić Luigi Messori 《Biometals》2016,29(5):905-911
Three structurally related gold(I) carbene complexes with bulky hydrophobic ligands i.e. 1–3 were investigated in solution for further consideration as candidate anticancer agents. Cytotoxic assays were subsequently conducted on bone marrow-derived preosteoclast cell line of human origin (FLG 29.1) and human colon cancer cells (HCT-116). A far greater cytotoxic activity was measured for compound 1 against HCT-116 cells compared to 2 and 3; conversely, all compounds were highly and similarly active against FLG 29.1 cells. Results obtained for the reaction of complexes 1 and 2 with RNase A documented the occurrence of a weak interaction with this model protein and the formation of a tiny amount of the corresponding adduct. Moreover, a certain reactivity of the complex 2 was also detected toward GSH. The general implications of the obtained results are discussed. 相似文献
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Alessandro Rubini Alessandro Frigo Emanuele Luigi Carniel 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):890-893
Context: Endocrinological factors have been recently described to affect respiratory mechanics.Objective: To review recent literature data, most of all obtained by the end-inflation occlusion method, describing the effects of molecules of endocrinological interest such as endothelin, erythropoietin and renin-angiotensin, on respiratory mechanics parameters.Methods: The papers considered in this review were found by inserting in Pubmed/Medline the following indexing terms: hormones, endothelin, erythropoietin, angiotensin and respiratory mechanics.Results: It was found that the above cited molecules, beside their well known physiological main effects, exhibit influences on respiratory mechanics, most of all on the airflow resistance, which was described to be increased by endothelin and angiotensin, and decreased by erythropoietin.Conclusions: A number of molecules of biological interest exhibit unexpected influences on respiratory mechanics. The clinical effects depend on the consequences of modified inspiratory pressure values the respiratory muscles have to perform for a given breathing pattern. 相似文献
996.
Exploring mild enzymatic sustainable routes for the synthesis of bio‐degradable aromatic‐aliphatic oligoesters 下载免费PDF全文
Alessandro Pellis Alice Guarneri Martin Brandauer Enrique Herrero Acero Henricus Peerlings Lucia Gardossi Georg M. Guebitz 《Biotechnology journal》2016,11(5):642-647
The application of Candida antarctica lipase B in enzyme‐catalyzed synthesis of aromatic‐aliphatic oligoesters is here reported. The aim of the present study is to systematically investigate the most favorable conditions for the enzyme catalyzed synthesis of aromatic‐aliphatic oligomers using commercially available monomers. Reaction conditions and enzyme selectivity for polymerization of various commercially available monomers were considered using different inactivated/activated aromatic monomers combined with linear polyols ranging from C2 to C12. The effect of various reaction solvents in enzymatic polymerization was assessed and toluene allowed to achieve the highest conversions for the reaction of dimethyl isophthalate with 1,4‐butanediol and with 1,10‐decanediol (88 and 87% monomer conversion respectively). Mw as high as 1512 Da was obtained from the reaction of dimethyl isophthalate with 1,10‐decanediol. The obtained oligomers have potential applications as raw materials in personal and home care formulations, for the production of aliphatic‐aromatic block co‐polymers or can be further functionalized with various moieties for a subsequent photo‐ or radical polymerization. 相似文献
997.
Maurizio Mazzei Baldassare Fronte Simona Sagona Maria Luisa Carrozza Mario Forzan Federica Pizzurro Carlo Bibbiani Vincenzo Miragliotta Francesca Abramo Francesca Millanta Marco Bagliacca Alessandro Poli Antonio Felicioli 《PloS one》2016,11(11)
The Western Honeybee is a key pollinator for natural as well as agricultural ecosystems. In the last decade massive honeybee colony losses have been observed worldwide, the result of a complex syndrome triggered by multiple stress factors, with the RNA virus Deformed Wing Virus (DWV) and the mite Varroa destructor playing crucial roles. The mite supports replication of DWV to high titers, which exert an immunosuppressive action and correlate with the onset of the disease.The aim of this study was to investigate the effect of 1,3–1,6 β-glucan, a natural innate immune system modulator, on honeybee response to low-titer natural and high-titer experimental DWV infection. As the effects exerted by ß-glucans can be remarkably different, depending on the target organism and the dose administered, two parallel experiments were performed, where 1,3–1,6 ß-glucan at a concentration of 0.5% and 2% respectively, was added to the diet of three cohorts of newly emerged honeybees, which were sampled from a Varroa-free apiary and harboured a low endogenous DWV viral titer. Each cohort was subjected to one of the following experimental treatments: no injection, injection of a high-copy number DWV suspension into the haemocel (experimental DWV infection) or injection of PBS into the haemocoel (physical injury). Control bees fed a ß-glucan-free diet were subjected to the same treatments. Viral load, survival rate, haemocyte populations and phenoloxidase activity of each experimental group were measured and compared. The results indicated that oral administration of 0.5% ß-glucan to naturally infected honeybees was associated with a significantly decrease of the number of infected bees and viral load they carried, and with a significant increase of the survival rate, suggesting that this natural immune modulator molecule might contribute to increase honeybee resistance to viral infection. 相似文献
998.
Christopher Delgado-Ratto Dionicia Gamboa Veronica E. Soto-Calle Peter Van den Eede Eliana Torres Luis Sánchez-Martínez Juan Contreras-Mancilla Anna Rosanas-Urgell Hugo Rodriguez Ferrucci Alejandro Llanos-Cuentas Annette Erhart Jean-Pierre Van geertruyden Umberto D’Alessandro 《PLoS neglected tropical diseases》2016,10(1)
Background
Characterizing the parasite dynamics and population structure provides useful information to understand the dynamic of transmission and to better target control interventions. Despite considerable efforts for its control, vivax malaria remains a major health problem in Peru. In this study, we have explored the population genetics of Plasmodium vivax isolates from Iquitos, the main city in the Peruvian Amazon, and 25 neighbouring peri-urban as well as rural villages along the Iquitos-Nauta Road.Methodology/ Results
From April to December 2008, 292 P. vivax isolates were collected and successfully genotyped using 14 neutral microsatellites. Analysis of the molecular data revealed a similar proportion of monoclonal and polyclonal infections in urban areas, while in rural areas monoclonal infections were predominant (p = 0.002). Multiplicity of infection was higher in urban (MOI = 1.5–2) compared to rural areas (MOI = 1) (p = 0.003). The level of genetic diversity was similar in all areas (He = 0.66–0.76, p = 0.32) though genetic differentiation between areas was substantial (PHIPT = 0.17, p<0.0001). Principal coordinate analysis showed a marked differentiation between parasites from urban and rural areas. Linkage disequilibrium was detected in all the areas ( = 0.08–0.49, for all p<0.0001). Gene flow among the areas was stablished through Bayesian analysis of migration models. Recent bottleneck events were detected in 4 areas and a recent parasite expansion in one of the isolated areas. In total, 87 unique haplotypes grouped in 2 or 3 genetic clusters described a sub-structured parasite population.Conclusion/Significance
Our study shows a sub-structured parasite population with clonal propagation, with most of its components recently affected by bottleneck events. Iquitos city is the main source of parasite spreading for all the peripheral study areas. The routes of transmission and gene flow and the reduction of the parasite population described are important from the public health perspective as well for the formulation of future control policies. 相似文献999.
We measured the chemiluminescence (CL) of human neutrophils (PMNLs) exposed to different concentrations of ofloxacin (2, 4, and 6 μg/ml) readily achievable in therapy. CL reaction during zymosan phagocytosis by PMNLs obtained from human healthy volunteers was registered in a computer-linked LKB 1251 luminometer. Ofloxacin did not induce significant variations on the respiratory burst of PMNLs. 相似文献
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