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High genetic variation and extensive gene flow may help forest trees with adapting to ongoing climate change, yet the genetic bases underlying their adaptive potential remain largely unknown. We investigated range-wide patterns of potentially adaptive genetic variation in 64 populations of European beech (Fagus sylvatica L.) using 270 SNPs from 139 candidate genes involved either in phenology or in stress responses. We inferred neutral genetic structure and processes (drift and gene flow) and performed differentiation outlier analyses and gene-environment association (GEA) analyses to detect signatures of divergent selection.Beech range-wide genetic structure was consistent with the species’ previously identified postglacial expansion scenario and recolonization routes. Populations showed high diversity and low differentiation along the major expansion routes. A total of 52 loci were found to be putatively under selection and 15 of them turned up in multiple GEA analyses. Temperature and precipitation related variables were equally represented in significant genotype-climate associations. Signatures of divergent selection were detected in the same proportion for stress response and phenology-related genes. The range-wide adaptive genetic structure of beech appears highly integrated, suggesting a balanced contribution of phenology and stress-related genes to local adaptation, and of temperature and precipitation regimes to genetic clines. Our results imply a best-case scenario for the maintenance of high genetic diversity during range shifts in beech (and putatively other forest trees) with a combination of gene flow maintaining within-population neutral diversity and selection maintaining between-population adaptive differentiation.

Identification of a common Diels-Alder pattern in three classes of bioactive natural products led us to study the synthesis and cycloaddition of a new class of cyclic dienes readily available from β,γ-unsaturated lactams. A practical and readily scalable route to the parent p-methoxybenzyl-protected 6- and 7-membered β,γ-unsaturated lactams was developed. These were readily transformed into the corresponding O-silylated dienes, which were reacted with dimethyl and diethyl fumarate to yield stereoselectively highly functionalized bicyclic adducts. These exhibited unexpected and versatile transformations upon acid hydrolysis depending on the nature of the dienophile substituents and the acid catalyst. All reactions have been performed on multigram quantities. These transformations provide a convenient, economical, and easily scalable pathway for the rapid construction of functionally and stereochemically dense privileged scaffolds for the construction of libraries of natural products-inspired molecules of pharmacological relevance.

Stem cell therapy has shown great promise for organ repair and regeneration. In the context of lung disease, such as radiation-induced lung damage (RILD) in cancer radiotherapy, mesenchymal stem cells (MSCs) have shown the ability to reduce damage possibly due to their immunomodulatory properties and other unknown mechanisms. However, once MSCs are transplanted into the body, little is known as to their localization or their mechanisms of action. In this work, we proposed, implemented, and validated a fluorescence endomicroscopy (FE) imaging technique that allows for the real-time detection and quantification of transplanted pre-labeled MSCs in vivo and tracking in a rat model. This protocol covers aspects related to MSCs extraction, labeling, FE imaging, and image analysis developed in a RILD rat model but applicable to other biological systems. © 2018 by John Wiley & Sons, Inc.

Introduction Hairy root cultures of Linum sp. are an alternative for the high production of lignans. Linum perenne is known to produce arylnaphthalene-type lignans such as justicidin B, isojusticidin and diphyllin. Objective To elucidate the presence of aryltetralin-type lignan diastereoisomers, besides the known arylnaphthalene-type lignans, in hairy roots of Linum perenne, and to determine the configurations of one diastereoisomer of 6-methoxypodophyllotoxin (6-MPTOX). Methods Lignans from hairy root cultures of Linum perenne were extracted and separated by HPLC. Arylnaphthalene-type lignans were identified by LC-MS, according to the literature. Two diastereoisomers of aryltetralin-type lignans were analysed by mass spectrometry and NMR spectroscopy. Results Numerous arylnaphthalene-type lignans (diphyllin-2-hexose-pentose, diphyllin-3-pentose and diphyllin-hexose) were identified in hairy root cultures. Methoxypodophyllotoxin, an aryltetralin-type lignan, was also identified, as well as one diastereoisomer. This aryltetralin-type lignan could be derived via 7-hydroxymatairesinol as a hypothetical biosynthetic pathway. The stereochemical configurations of aryltetralin isomers were determined. Conclusion Arylnaphthalene and two diastereoisomers of aryltetralin-type lignans are produced in Linum perenne hairy root cultures. Matairesinol, the precursor of justicidin B, also seems to be converted into 6-MPTOX via 7-hydroxymatairesinol. This is the first report of the stereochemical configurations of an aryltetralin-type lignan other than podophyllotoxin (PTOX). Copyright © 2015 John Wiley & Sons, Ltd.

The clinical benefits of oseltamivir (Tamiflu) are well established, but the effects of antiviral treatment on the immune response are poorly understood. By use of flow cytometric analyses and the mouse model, we thoroughly investigated the impact of such a treatment on the immune response and the generation of protective immunity to influenza. We demonstrated that influenza-specific CD8(+) effector T cell recruitment was reduced up to 81% in the lungs of mice treated with oseltamivir (5 or 50 mg/kg twice daily; EC50 49 nM in vitro) compared to saline controls, but cell generation was unaffected in draining lymph nodes. Importantly, we showed that oseltamivir administration significantly decreased the pools of tissue-resident and circulating effector memory (93.7%) and central memory CD8(+) T cells (45%) compared to saline controls. During heterologous secondary infection, a decreased memory CD8(+) T cell pool combined with reduced generation of secondary influenza-specific effectors in the lymph nodes resulted in 10-fold decreased CD8(+) T cell recall responses, which increased mouse morbidity and delayed viral clearance. Furthermore, antiviral administration led to a significant 5.7-fold decreased production of functional anti-influenza antibodies. Thus, our study demonstrates that antiviral treatment affects the development of the adaptive immune response and protective immunity against influenza.

Afin de montrer l'importance de la reglementation et de la productivite naturelle dans la valorisation des surfaces de production ostreicoles, nous avons estime une fonction de prix hedonique des concessions ostreicoles arcachonnaises. Les « terres ostreicoles » ont comme particularite d'etre des concessions du Domaine Public Maritime et sont a ce titre soumises a son regime protecteur. Neanmoins, loin d'entraver l'activite ostreicole par les contraintes qu'elle impose, la reglementation se revele etre une garante du maintien d'un niveau satisfaisant de productivite naturelle des concessions pour permettre une reproduction et une croissance des huitres dans des conditions favorables. Ainsi, les resultats de la modelisation montrent que plus de la moitie du prix d'echange des concessions est determine par les conditions reglementaires regissant leur utilisation. Ils soulignent egalement que les conditions du milieu ne sont pas identiques sur l'ensemble du Bassin d'Arcachon justifiant une reglementation adaptee aux differences de productivite naturelle. To demonstrate the importance of regulation and the natural productivity in the economic valuation of oyster production areas, we estimated a hedonic price function of oyster leases in Arcachon Bay. The “oyster land” have the particularity to be concessions of Maritime Public Domain and are therefore subject to its protective system. Nevertheless, far from hindering the oyster farming by the constraints it imposes, the regulation appears to be a guarantor of maintaining a level of natural productivity concessions allowing a satisfactory reproduction and growth of oysters in favorable conditions. Thus, the modeling results show that more than half the price of trade concessions is determined by the regulatory requirements governing their use. They also show that environmental conditions are not identical across the Bay of Arcachon, while justifying the regulation has to be adaptive to the natural productivity differences.

Miscanthus × giganteus is often regarded as one of the most promising crops to produce sustainable bioenergy. This perennial crop, renowned for its high productivity associated with low input requirements, in particular regarding fertilizers, is thought to have low environmental impacts, but few data are available to confirm this. Our study aimed at assessing nitrate leaching from Miscanthus × giganteus crops in farmers' fields, thus including a wide range of soil and cropping system conditions. We focused on the first years of growth after planting as experimental studies have suggested that Miscanthus × giganteus, once established, results in low nitrate leaching. We combined on-farm measurements and modeling to estimate drainage, leached nitrogen, and nitrate concentration in drainage water in 38 fields located in Center-East France during two winters (November 2010 to March 2011, November 2011 to March 2012). Nitrate leaching and nitrate concentration in drainage water were on average very low. Nitrate leaching averaged 6 kg N ha−1 whereas nitrate concentration averaged 12 mg l−1. These low values are attributable to the low estimates of drainage water (mean = 166 mm) but also to the low soil mineral nitrogen contents measured at the beginning of winter (mean = 37 kg N ha−1). Our results were, however, very variable, mainly due to the crop age: nitrate leaching and nitrate concentration were critically higher during the winter following the first growth year of Miscanthus × giganteus, reflecting the low development of the crop. This variability was also explained by the range of soil and cropping conditions explored in the on-farm design: shallow and/or sandy soils as well as fields where establishment failed had a higher risk of nitrate leaching.

In search of a next generation molecule to the novel wake-promoting agent modafinil, a series of aryl-heteroayl-derived wakefulness enhancing agents (in rats) was developed. From this work, compound 16 was separated into its enantiomers to profile them individually.

Adjuvant polyarthritis (AP) in rats is known to result in extensive bone loss. This study investigates the mechanisms responsible for the early trabecular osteopenia evaluated at a single point in time--2 weeks after adjuvant injection--in the hindpaw of female Lewis rats using biochemical and histomorphometric methods. At this early point in time, the inflammation was generalized (inflammatory score, 20; albumin/globulin, -80% versus control). Histomorphometric analysis of the noninjected femur showed that the trabecular bone volume was significantly decreased (-28% versus control) in both proximal and distal parts, and the femur growth rate was unaffected. The trabecular osteopenia was associated with a 90% decrease in osteoid surface and a concomitant thinning (-19%) of the trabeculae. Both the double-fluorescence-labeled surface and the osteoblast surface were also markedly decreased (-75%). In addition, the mineral apposition rate was reduced (-50%) and the bone formation rate was decreased by as much as 90%. The trabecular bone volume was decreased in relation with the extent of double-fluorescence labeling (r = 0.38, p = 0.03) and bone formation rate (r = 0.42, p = 0.01), suggesting that the generalized osteopenia resulted from the reduced bone formation. This was associated with a 26% reduction in plasma osteocalcin. Neither the osteoclast surface nor the number of osteoclasts was consistently affected. However, urinary hydroxyproline was increased by 100-200%, which likely reflected the cartilage and bone destruction at the site of injection. The present data show that the early extensive osteopenia observed 2 weeks after AP induction in rats results from defective bone formation with unchanged bone resorption. The role of cytokines in such an inhibitory effect on bone formation remains to be determined.

Sugars modulate many vital metabolic and developmental processes in plants, from seed germination to flowering, senescence and protection against diverse abiotic and biotic stresses. However, the exact mechanisms involved in morphogenesis, developmental signalling and stress tolerance remain largely unknown. Here we report the characterization of a novel Arabidopsis thaliana mutant, sweetie, with drastically altered morphogenesis, and a strongly modified carbohydrate metabolism leading to elevated levels of trehalose, trehalose-6-phosphate and starch. We additionally show that the disruption of SWEETIE causes significant growth and developmental alterations, such as severe dwarfism, lancet-shaped leaves, early senescence and flower sterility. Genes implicated in sugar metabolism, senescence, ethylene biosynthesis and abiotic stress were found to be upregulated in sweetie. Our physiological, biochemical, genetic and molecular data indicate that the mutation in sweetie was nuclear, single and recessive. The effects of metabolizable sugars and osmolytes on sweetie morphogenesis were distinct; in light, sweetie was hypersensitive to sucrose and glucose during vegetative growth and a partial phenotypic reversion took place in the presence of high sorbitol concentrations. However, SWEETIE encodes a protein that is unrelated to any known enzyme involved in sugar metabolism. We suggest that SWEETIE plays an important regulatory function that influences multiple metabolic, hormonal and stress-related pathways, leading to altered gene expression and pronounced changes in the accumulation of sugar, starch and ethylene.

Objective To study the effects of a matrix metalloproteinase (MMP) inhibitor (S-34219) on osteoarthritis (OA) cartilage cultures and in the meniscectomized guinea pig model of OA. Methods The inhibitory activity of S-34219 on MMPs and aggrecanase was studied by fluorimetry and immunoassay, respectively. The effects of S-34219 on proteoglycan and collagen degradation were studied in cultures of rabbit and human cartilage. Medial meniscectomy was performed on 29 Hartley male guinea pigs, and these animals were randomly allocated to 1 of 3 groups: a control meniscectomized group (MNXc) receiving the vehicle, or a meniscectomized group receiving either 10 mg/kg or 20 mg/kg S-34219, administered twice per day by oral gavage for 12 weeks from day 1 after surgery. An additional group comprised sham-operated animals. Tibial cartilage from the operated left knee was processed for histologic assessment of OA lesions. Results The 50% inhibitory concentration (IC50) of S-34219 on MMPs 1, 2, 3, 8, 9, and 13 was 55, 0.1, 0.5, 0.1, 0.03, and 0.2 nM, respectively; the IC50 on aggrecanase 1 was 190 nM. In cultured rabbit cartilage, 100 nM S-34219 strongly inhibited MMP-dependent degradation of collagen and proteoglycans. A concentration 100 times higher was needed to inhibit aggrecanase-dependent degradation. In cultures of human OA cartilage, 100 nM S-34219 inhibited spontaneous type II collagen degradation by 66% and proteoglycan degradation by only 22%. For in vivo studies, treated groups were compared with the MNXc group and the results, expressed as the percentage variation versus MNXc, were as follows: in the 10 and 20 mg/kg groups, a significant decrease (P < 0.05) in global histologic score (−12% and −14%, respectively) was observed, and this was associated with a significant increase (P < 0.05) in cartilage thickness (+19% and +18%, respectively). Neither dose level changed the proteoglycan content. Conclusion In both treated animal groups, S-34219 significantly prevented the loss of cartilage thickness, probably by inhibiting collagen breakdown that normally leads to the erosion of fibrillated superficial areas. The absence of a protective effect on glycosaminoglycan loss, both in vitro and in vivo, suggests that aggrecanases may have an important role in cartilage loss. This study reinforces the relevance of these models for testing chondroprotective drugs, and the potential role of dual inhibitors of collagenase and aggrecanase as disease-modifying drugs in the management of OA.

It is well known that the immune response decreases during aging, leading to a higher susceptibility to infections, cancers and autoimmune disorders. Most widely studied have been alterations in the adaptive immune response. Recently, the role of the innate immune response as a first-line defence against bacterial invasion and as a modulator of the adaptive immune response has become more widely recognized. One of the most important cell components of the innate response is neutrophils and it is therefore important to elucidate their function during aging. With aging there is an alteration of the receptor-driven functions of human neutrophils, such as superoxide anion production, chemotaxis and apoptosis. One of the alterations underlying these functional changes is a decrease in signalling elicited by specific receptors. Alterations were also found in the neutrophil membrane lipid rafts. These alterations in neutrophil functions and signal transduction that occur during aging might contribute to the significant increase in infections in old age.

Since tamoxifen is widely used in breast cancer treatment and has been proposed for the prevention of breast cancer, its endometrial iatrogenic effects must be carefully examined. We have investigated the association between endometrial cancer and tamoxifen use or other treatments in women treated for breast cancer in a case-control study. Cases of endometrial cancer diagnosed after breast cancer (n = 135) and 467 controls matched for age, year of diagnosis of breast cancer and hospital and survival time with an intact uterus were included. Women who had received tamoxifen were significantly more likely to have endometrial cancer diagnosed than those who had not (crude relative risk = 4.9, p = 0.0001). Univariate and adjusted analyses showed that the risk increased with the length of treatment (p = 0.0001) or the cumulative dose of tamoxifen received (p = 0.0001), irrespective of the daily dose. Women who had undergone pelvic radiotherapy also had a higher risk (crude relative risk = 7.8, p = 0.0001). After adjusting for confounding factors, the risk was higher for tamoxifen users (p = 0.0012), treatment for more than 3 years (all p < 0.03) and pelvic radiotherapy (p = 0.012). Women who had endometrial cancer and had received tamoxifen had more advanced disease and poorer prognosis than those with endometrial cancer who had not received this treatment. Our results suggest a causal role of tamoxifen in endometrial cancer, particularly when used as currently proposed for breast cancer prevention. Pelvic radiotherapy may be an additional iatrogenic factor for women with breast cancer. Endometrial cancers diagnosed in women treated with tamoxifen have poorer prognosis. Women who receive tamoxifen for breast cancer should be offered gynaecological surveillance during and after treatment. A long-term evaluation of the risk-benefit ratio of tamoxifen as a preventive treatment for breast cancer is clearly warranted.

A 54-year-old patient, admitted to the intensive care unit with a diagnosis of severe pancreatitis, developed circulatory shock that failed to respond to standard vasopressor treatment: epinephrine and norepinephrine. Addition of vasopressin helped reduce standard catecholamine need while maintaining adequate arterial blood pressure. Vasopressin appears to be a promising agent for maintaining arterial pressure during septic shock or systemic inflammatory response syndrome, but due to limited data and potential side effects, its use as first-line treatment for these indications is not recommended.

Only one of the four enantiomers of 5-fluoromethylornithine 1 was an irreversible inhibitor of ornithine aminotransferase. The active enantiomer 1a was synthesized from diaminoadipic acid 2 with a chemical diastereomeric separation and an enantiomeric resolution by hydrolysis of a phenylacetamide with benzylpenicillinase.

Metabolism of arachidonic acid through the 5-lipoxygenase (LO) pathway generates compounds that stimulate osteoclastic bone resorption; since LO metabolites might play a role in bone loss due to excessive resorption it was tried to develop a series of antiresorptive agents starting from an already known LO inhibitor. Of the 35 compounds synthesized, 11 strongly inhibited (10 mumol/l) retinoic acid-induced bone resorption in cultured mouse calvariae; they were also tested for their effect on LO activity using rat peritoneal neutrophils, but no correlation could be drawn between inhibition of LO and bone resorption. Other pathways, still to be identified, must therefore be targeted by these compounds even though LO inhibition might contribute to their effects on bone. Two compounds selected for further studies were found active on parathyroid hormone-induced osteolysis, while they had no effect on basal resorption; they must, therefore, act at some key point in the process of activation of osteoclastic resorption. This series of compounds may represent a new way for the treatment of bone loss due to excessive resorption.

A concise approach to 5-arylamino-4H-pyran-4-ones is described via palladium-catalyzed amination reaction. The methodology involved in this Letter is based on protection/deprotection protocols and on manipulation of the 5-hydroxy group of readily available kojic acid. It would provide a new entry to a range of 5-arylamino-4H-pyran-4-ones via Buchwald–Hartwig-type amination reaction on 4H-pyran-4-one unit.