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Humanized mice are widely used to study the human immune system in vivo and develop therapies for various human diseases. Human peripheral blood mononuclear cells (PBMC)-engrafted NOD/Shi-scid IL2rγnull (NOG) mice are useful models for characterization of human T cells. However, the development of graft-versus-host disease (GVHD) limits the use of NOG PBMC models. We previously established a NOG-major histocompatibility complex class I/II double knockout (dKO) mouse model. Although humanized dKO mice do not develop severe GVHD, they have impaired reproductive performance and reduced chimerism of human cells. In this study, we established a novel beta-2 microglobulin (B2m) KO mouse model using CRISPR/Cas9. By crossing B2m KO mice with I-Ab KO mice, we established a modified dKO (dKO-em) mouse model. Reproductivity was slightly improved in dKO-em mice, compared with conventional dKO (dKO-tm) mice. dKO-em mice showed no signs of GVHD after the transfer of human PBMCs; they also exhibited high engraftment efficiency. Engrafted human PBMCs survived significantly longer in the peripheral blood and spleens of dKO-em mice, compared with dKO-tm mice. In conclusion, dKO-em mice might constitute a promising PBMC-based humanized mouse model for the development and preclinical testing of novel therapeutics for human diseases.

Resilience to soil water deficit is a priority of many maize breeding programmes. Its genetic analysis requires estimators that characterise each genotype in a reproducible way. We have tested and compared three methods for that, namely (i) the ability of hybrids to maintain leaf growth in a range of soil water potentials in a phenotyping platform, (ii) a direct estimator of resilience of seed number to water deficit in a network of field experiments and (iii) classical methods involving tolerance indices and variance analysis. A drought index was obtained by averaging soil water potential, measured with tensiometers, for the phenological phase during which seed number is determined (evaluated for each individual hybrid in each site). It closely correlated with seed number in each of the 19 hybrids that were analysed over 14 environmental situations in France, Hungary and Chile. The slope of the regression line between drought index and seed number, established for each hybrid, was taken as an estimate of the resilience to soil water deficit of that hybrid. Resilience estimated in this way varied 2-fold in the set of studied hybrids, and correlated with resilience of leaf growth to soil water deficit in short-term experiments in the phenotyping platform. In contrast, the resilience estimated via the interaction genotype × watering treatment resulted non-significant because of large differences in drought indices between genotypes in a given watering treatment. We therefore propose that direct estimation of resilience to water deficit is feasible in the field with a minimum amount of environmental measurements. This provides estimations that are consistent with those measured in a phenotyping platform. The combination of both estimates provides insight into the mechanisms associated with resilience of each hybrid, potentially contributing to accelerate the genetic gain.

International audience; The secretion of corticosterone in response to stress is thought to be an adaptive mechanism, which promotes immediate survival at the expense of current reproduction. However, at the individual level, the hypothesis of a corticosterone-related survival appears to be complex. In this study, we tested this hypothesis by combining for the first time an experimental manipulation of corticosterone levels and capture-mark-recapture (CMR) models. To do so, we increased corticosterone levels of chick-rearing Black-legged kittiwakes (Rissa tridactyla) via subcutaneous implants. Then, we monitored the long-term survival of kittiwakes over the 2 consecutive years. Corticosterone-implanted birds showed a significantly lower apparent annual survival than sham-implanted ones (46.9% vs 77.8%). This result is supported by the well-known deleterious effects of elevated corticosterone levels on cognitive and immune functions. Alternately and in the light of recent studies, our experimental manipulation may have down-regulated the endogenous secretion of corticosterone through a prolonged negative feedback. If so, the corticosterone-implanted kittiwakes may have failed to trigger an appropriate stress response during subsequent life-threatening perturbations, hence being unable to adjust their behavior and physiology toward immediate survival. This study highlights the complex long-term consequences of corticosterone manipulation on fitness in free-living vertebrates.

We examined how short-term impacts of experimentally increased foraging effort by one parent reverberate around the family in a monomorphic seabird (little auk, Alle alle), and whether these effects depend on offspring sex. In many species, more effort is required to rear sons successfully than daughters. However, undernourishment may have stronger adverse consequences for male offspring, which could result in a lower fitness benefit of additional parental effort when rearing a son. We tested two alternative hypotheses concerning the responses of partners to handicapping parents via feather clipping: partners rearing a son are (1) more willing or able to compensate for the reduced contribution of their mate, or (2) less willing or able to compensate, compared to those rearing a daughter. Hypothesis 1 predicts that sons will be no more adversely affected than daughters, and the impact on parents will be greater when rearing a son. Hypothesis 2 predicts that sons will be more adversely affected than daughters, and parents raising a son less affected. Although experimental chicks of both sexes fledged in poorer condition than controls, sons attained higher mass and more rapid growth than daughters in both groups. Clipped parents lost a similar proportion of their initial mass regardless of chick sex, whereas partners of clipped birds lost more mass when rearing a son. These results support hypothesis 1: impacts of increased foraging effort by one parent were felt by offspring, regardless of their sex, and by the partners of manipulated birds, particularly when the offspring was male.

E-type cyclins are thought to drive cell-cycle progression by activating cyclin-dependent kinases, primarily CDK2. We previously found that cyclin E-null cells failed to incorporate MCM helicase into DNA prereplication complex during G(0) --> S phase progression. We now report that a kinase-deficient cyclin E mutant can partially restore MCM loading and S phase entry in cyclin E-null cells. We found that cyclin E is loaded onto chromatin during G(0) --> S progression. In the absence of cyclin E, CDT1 is normally loaded onto chromatin, whereas MCM is not, indicating that cyclin E acts between CDT1 and MCM loading. We observed a physical association of cyclin E with CDT1 and with MCMs. We propose that cyclin E facilitates MCM loading in a kinase-independent fashion, through physical interaction with CDT1 and MCM. Our work indicates that-in addition to their function as CDK activators-E cyclins play kinase-independent functions in cell-cycle progression.

Cell transformation by simian virus 40 (SV40) results mostly from the highly oncogenic activities of the large T antigen (LT), which corrupts the cellular checkpoint mechanisms that guard cell division and the transcription, replication, and repair of DNA. The most prominent LT targets are the retinoblastoma protein (pRb) and p53. Here we report that LT binds directly to Fbw7, the substrate recognition component of the SCF(Fbw7) ubiquitin ligase and a human tumor suppressor. LT binding mislocalizes the nucleolar Fbw7gamma isoform to the nucleoplasm. Interestingly, the binding of LT to Fbw7 occurs via a decoy phospho-epitope within the C terminus of LT that closely mimics the consensus Cdc4 phospho-degron found within Fbw7 substrates. We demonstrate that, using this mode of interaction, LT can interfere with Fbw7-driven cyclin E turnover in vivo and causes increased cyclin E-associated kinase activity. Our data suggest that LT competes with cellular proteins for Fbw7 binding in a substrate-like fashion.

Autophosphorylation-triggered ubiquitination has been proposed to be the major pathway regulating cyclin E protein abundance: phosphorylation of cyclin E on T380 by its associated CDK allows binding to the receptor subunit, Fbw7, of the SCFFbw7 ubiquitin ligase. We have tested this model in vivo and found it to be an inadequate representation of the pathways that regulate cyclin E degradation. We show that assembly of cyclin E into cyclin E-Cdk2 complexes is required in vivo for turnover by the Fbw7 pathway; that Cdk2 activity is required for cyclin E turnover in vivo because it phosphorylates S384; that phosphorylation of T380 in vivo does not require Cdk2 and is mediated primarily by GSK3; and that two additional phosphorylation sites, T62 and S372, are also required for turnover. Thus, cyclin E turnover is controlled by multiple biological inputs and cannot be understood in terms of autophosphorylation alone.

The main objective of the research project is to develop market solutions and strategies for various forest outputs, which are considered to be not, or hardly, marketable. The phenomenon of ‘public goods’ is considered under dynamic conditions, in which marketability is rather a matter of product and framework development than of objective circumstances. Solutions were found on the basis of 98 case studies, field developments in cooperation with forest landowners and on literature studies. The RES products are mainly offered at market-oriented prices. With the broad field of services the creative possibilities with regard to the height and the mode of price-incline are much larger in comparison to mass products. Market development depends on contracting ability and existing transaction organization. The relationship between the character of products and the chosen form of contracting and distribution is shown on the basis of transaction–cost theory. Household surveys show that the acceptability of pricing can be quite high, depending on the kind of offer. In this context, it is important to differentiate between public opinion and specific user-group opinions. Finally, some basic ideas are presented on how the marketability of hardly marketable or so-called public goods can be improved. In this context, the market aspect of non-material values, the conditions of market development, the complexity of products and the human factor in marketability are discussed.

A new fluoride ion cleavable linker serves as starter unit for iterative asymmetric aldol reactions on a solid support. The synthetic protocol relies on the boron enolate chemistry of D. A. Evans and a cyclic reestablishment of key functionalities. It entails the opportunity for the generation of di- and triketide libraries.

With cost pressures brought to the forefront by the growth of managed care, the integration of healthcare information systems is more important than ever. Providers of healthcare information are under increasing pressure to provide timely information to end users in a cost effective manner. Organizations have had to decide between the strong functionality that a multi-vendor 'best of breed' architecture provides and the strong integration provided by a single-vendor solution. As connectivity between systems increased, these interfaces were migrated to work across serial and eventually, network, connections. In addition, the content of the information became standardized through efforts like HL7 and ANSI X12 and Edifact. Although content-based standards go a long way towards facilitating interoperability, there is also quite a bit of work required to connect two systems even when they both adhere to the standard. A key to accomplishing this goal is increasing the connectivity between disparate systems in the healthcare environment. Microsoft is working with healthcare organizations and independent software vendors to bring Microsoft's powerful enterprise object technology, ActiveX, to the healthcare industry. Whilst object orientation has been heralded as the 'next big thing' in computer applications development, Microsoft believe that, in fact, component software is the technology which will provide the greatest benefit to end users.

CDK1 has long been known to orchestrate the passage of mammalian cells into and through mitosis. Recent work revisits the idea that CDK1, in conjunction with cyclin E, participates in S-phase entry as well. The new results shed light on a recent cell-cycle mystery, and provide another dramatic example of apparent functional redundancy among cyclins and cyclin-dependent kinases.

The purpose of this clinical study was to evaluate the comparative cleaning efficacy of three surfactant cleaners: BAUSCH & LOMB® SENSITIVE EYES® Daily Cleaner, CooperVision∗ MiraFlow® Extra Strength Daily Cleaner, and Alcon Opti-Cleans® II Daily Cleaner. One hundred seventy-seven patients were entered into this 3-month, double-blind, one-eye/one-eye comparison study at six investigational sites. The results of investigator microscopic examination and laboratory quantitation of total protein deposition indicated no difference between the contact lenses cleaned with SENSITIVE EYES Daily Cleaner and Opti-Clean II (lens material groups 1 and 3) or MiraFlow Extra Strength (lens material groups 1, 3, and 4). Contact lenses from lens material group 2 cleaned with SENSITIVE EYES Daily Cleaner had less total protein than the lenses cleaned with MiraFlow.