Synthesis and monoamine transporter affinity of 2beta-carbomethoxy-3beta-(4'-p-substituted phenyl)-piperidine analogs of cocaine

A series of novel piperidine based analogs of cocaine was synthesized and evaluated in vitro against the three monoamine transporters to develop new potential selective SERT radiotracers. Modification of the phenyl substitution with five-membered heterocyclic groups resulted in a wide affinity and selectivity scale. Radiolabeling and mouse in vivo study was performed on the piperidine analog of ZIENT, which crossed the blood-brain barrier but failed to selectively accumulate in the regions of the brain rich in SERT.     

Flexible synthesis and biological evaluation of novel 5-deoxyadenophorine analogues

Adenophorine and its 5-deoxy analogue have been identified as natural iminosugars with efficient glycosidase inhibitory effects. The syntheses and biological evaluation of two new series of 5-deoxyadenophorine analogues in their racemic form are reported. The compounds 12e and 13d bearing a C11 and C7 alkyl chain, respectively, were found to be potent inhibitors of the beta-glucosidase from almond with Ki near to 60 microM. The compounds 13a,d which possess a 3,4-cis stereochemistry were efficient on glucosidases but also on the beta-galactosidase, what was not observed with the 3,4-trans series 12.     

Single argonaute protein from Toxoplasma gondii is involved in the double-stranded RNA induced gene silencing

Here, we report the characterization of the argonaute protein from Toxoplasma gondii. This is the first report on the function of an argonaute protein with structural features overlapping between argonaute proteins of archaeal bacteria and eukaryotes. The full-length cDNA clone has an open reading frame of 1575 bp, which encodes a 524 amino acid protein with a calculated molecular weight of 58.5 kDa and an estimated isoelectric point of 9.4. This argonaute protein, called TgAgo, exhibits unique features: (i) TgAgo is smaller than reported argonaute proteins derived from higher eukaryotic organisms (i.e. Arabidopsis, human and nematodes) but has a similar size to those from archaeal bacteria (i.e. Pyrococcus furiosus and Archaeoglobus fulgidus); (ii) TgAgo contains a conserved PIWI domain and non-conserved PAZ domain; (iii) TgAgo is mainly localized in the cytoplasm; and (iv) despite its small size, TgAgo participates in the double-stranded RNA induced gene silencing. Using a transgenic parasite line, in which TgAgo expression is lowered, we showed that the expression of TgAgo is required for the double-stranded RNA induced gene silencing, RNA interference mechanism.     

Autotoxicity Against Germination and Seedling Emergence in Cistus ladanifer L

Autotoxic species are those which adversely affect their own seeds’ germination and/or seedling development. Cistus ladanifer L (labdanum or jara) has been shown to have a pattern of allelopathic behaviour against the herbs that share its habitat. The present work studied whether an autotoxic effect also exists. The aqueous solution obtained from washing jara leaves was found by itself to inhibit germination and cotyledon emergence of the species’ seeds. When these same trials were carried out in soils, autotoxicity was observed only from leaves and soils collected in winter. This was so both in soils collected away from the influence of the jaral to which was added the greatest concentration of aqueous extract prepared from the leaves, and in soils collected within the jaral, except that in the latter group of soils germination was inhibited with or without the addition of C. ladanifer extracts. This autotoxic behaviour could be involved in the species’ own population control, and would explain the scant self-regeneration within established C. ladanifer stands.     

Proteomic analysis of Brucella suis under oxygen deficiency reveals flexibility in adaptive expression of various pathways

Low oxygen tension was proposed to be one of the environmental parameters characteristic of the patho‐physiological conditions of natural infections by Brucella suis. We previously showed that various respiratory pathways may be used by B. suis in response to microaerobiosis and anaerobiosis. Here, we compare the whole proteome of B. suis exposed to such low‐oxygenated conditions to that obtained from bacteria grown under ambient air using 2‐D DIGE. Data showed that the reduction of basal metabolism was in line with low or absence of growth of B. suis. Under both microaerobiosis and anaerobiosis, glycolysis and denitrification were favored. In addition, fatty acid oxidation and possibly citrate fermentation could also contribute to energy production sufficient for survival under anaerobiosis. When oxygen availability changed and became limiting, basic metabolic processes were still functional and variability of respiratory pathways was observed to a degree unexpected for a strictly aerobic microorganism. This highly flexible respiration probably constitutes an advantage for the survival of Brucella under the restricted oxygenation conditions encountered within host tissue.     

Tarsal morphology and attachment ability of the codling moth Cydia pomonella L. (Lepidoptera, Tortricidae) to smooth surfaces

Despite several studies on the attachment ability of different insect taxa, little is known about this phenomenon in adult Lepidoptera. In this study we combined morphological and experimental analyses of tarsal adhesive devices and the attachment ability of the codling moth Cydia pomonella (L.) (Lepidoptera, Tortricidae) to smooth surfaces. Pretarsi of C. pomonella attach to smooth substrates by means of their smooth, flexible and well developed arolia. Using the centrifugal force measurement technique, friction forces of males and females were assessed on hydrophobic and hydrophilic glass surfaces. Adults of both sexes generated similar forces in spite of the noticeable difference in their body masses. That is why males showed significantly higher safety factors (attachment force divided by body weight) compared to those of females. Hydrophobicity of the substrate had no considerable effect on friction forces. For females, friction forces (sliding parallel to the substrate plane) were compared with adhesive forces (pulling off perpendicularly from the substrate plane) measured on Plexiglas surfaces. It can be concluded that the attachment system of C. pomonella is rather robust against physico-chemical properties of the substrate and is able to achieve a very good attachment on vertical and horizontal substrata.     

A machine learning approach for the identification of protein secondary structure elements from electron cryo-microscopy density maps

The accuracy of the secondary structure element (SSE) identification from volumetric protein density maps is critical for de-novo backbone structure derivation in electron cryo-microscopy (cryoEM). It is still challenging to detect the SSE automatically and accurately from the density maps at medium resolutions (～5-10 ?). We present a machine learning approach, SSELearner, to automatically identify helices and β-sheets by using the knowledge from existing volumetric maps in the Electron Microscopy Data Bank. We tested our approach using 10 simulated density maps. The averaged specificity and sensitivity for the helix detection are 94.9% and 95.8%, respectively, and those for the β-sheet detection are 86.7% and 96.4%, respectively. We have developed a secondary structure annotator, SSID, to predict the helices and β-strands from the backbone Cα trace. With the help of SSID, we tested our SSELearner using 13 experimentally derived cryo-EM density maps. The machine learning approach shows the specificity and sensitivity of 91.8% and 74.5%, respectively, for the helix detection and 85.2% and 86.5% respectively for the β-sheet detection in cryoEM maps of Electron Microscopy Data Bank. The reduced detection accuracy reveals the challenges in SSE detection when the cryoEM maps are used instead of the simulated maps. Our results suggest that it is effective to use one cryoEM map for learning to detect the SSE in another cryoEM map of similar quality.     

Grape seed and skin extract mitigates garlic-induced oxidative stress in rat liver

Garlic is a commonly used spice in folk medicine that can exert adverse health effects when given at a high dose. Grape seed and skin extract (GSSE) exhibits a variety of beneficial effects even at a high dose. In the present study we evaluated the toxicity of high-dose garlic treatment on liver and the protective effect of GSSE. Rats were intraperitoneally administered either with garlic extract (5 g·(kg body weight)(-1)) or GSSE (500 mg·(kg body weight)(-1)) or a combination of garlic and GSSE at the same doses daily for 1 month. Plasma and hepatic levels of cholesterol, triacylglycerol, and transaminases and liver antioxidant status were evaluated. Data showed that a high garlic dose induced liver toxicity and a pro-oxidative status characterized by increased malondialdehyde and decreased antioxidant enzyme activities as catalase, peroxidase, and superoxide dismutase. Garlic increased intracellular H(2)O(2) but decreased free iron and Ca(2+). GSSE alone or in co-treatment with garlic had the reverse effect and counteracted almost all garlic-induced deleterious impacts to near control levels. In conclusion, a high garlic dose induced a pro-oxidative state characterized by the Fenton reaction between H(2)O(2) and free iron, inducing Ca(2+) depletion, while GSSE exerted antioxidant properties and Ca(2+) repletion.     

Lack of nitric oxide synthases increases lipoprotein immune complex deposition in the aorta and elevates plasma sphingolipid levels in lupus

Systemic lupus erythematosus (SLE) patients display impaired endothelial nitric oxide synthase (eNOS) function required for normal vasodilatation. SLE patients express increased compensatory activity of inducible nitric oxide synthase (iNOS) generating excess nitric oxide that may result in inflammation. We examined the effects of genetic deletion of NOS2 and NOS3, encoding iNOS and eNOS respectively, on accelerated vascular disease in MRL/lpr lupus mouse model. NOS2 and NOS3 knockout (KO) MRL/lpr mice had higher plasma levels of triglycerides (23% and 35%, respectively), ceramide (45% and 21%, respectively), and sphingosine 1-phosphate (S1P) (21%) compared to counterpart MRL/lpr controls. Plasma levels of the anti-inflammatory cytokine interleukin 10 (IL-10) in NOS2 and NOS3 KO MRL/lpr mice were lower (53% and 80%, respectively) than counterpart controls. Nodule-like lesions in the adventitia were detected in aortas from both NOS2 and NOS3 KO MRL/lpr mice. Immunohistochemical evaluation of the lesions revealed activated endothelial cells and lipid-laden macrophages (foam cells), elevated sphingosine kinase 1 expression, and oxidized low-density lipoprotein immune complexes (oxLDL-IC). The findings suggest that advanced vascular disease in NOS2 and NOS3 KO MRL/lpr mice maybe mediated by increased plasma triglycerides, ceramide and S1P; decreased plasma IL-10; and accumulation of oxLDL-IC in the vessel wall. The results expose possible new targets to mitigate lupus-associated complications.     

Intra-specific variability in biomass partitioning and carbon isotopic discrimination under moderate drought stress in seedlings from four <Emphasis Type="Italic">Pinus pinaster</Emphasis> populations

The response to drought of 20 open-pollinated families from four Pinus pinaster Ait. populations covering a latitudinal cline (France, Central and Southern Spain, and Morocco) was assessed. The seedlings were cultivated in a greenhouse under controlled temperature and vapor pressure deficit for 120 days, and subjected to two watering regimes for 60 days. Different biomass partitioning variables, pre-dawn water potential, and isotopic discrimination of ¹³C in needles (Δ) as surrogate of long-term water use efficiency were estimated for each seedling at the end of the experiment. In response to the imposed drought, there was no change in the root biomass partitioning, but the overall Δ values decreased in response to water stress. All the families of the population from Morocco showed the highest investment in roots, regardless of the watering regime imposed. Inter-family differences within populations were also significant for most parameters as confirmed by the heritability values estimated (higher under the well-watered treatment). The studied P. pinaster populations showed different strategies of response to drought. This may represent an important mechanism by local populations in facing future climatic change. The results could be of value in forest conservation and breeding programs of maritime pine in the future.