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University–industry R&D collaboration is an important means to improve innovation efficiency; many governments have issued policies to promote it. The most frequent policy instruments implemented by policy-makers to foster firms’ innovation are subsidies and tax incentives. The article elaborated on how subsidies and tax incentives influence the R&D collaboration efficiency through a panel dataset from 2009 to 2015 in China. The result showed that subsidies and tax incentives have a positive effect on collaboration efficiency, and the effect of subsidies on output is bigger than that of tax incentives. Taking the intensity of subsidy as a threshold variable, there is a significant single threshold effect on collaboration efficiency. However, there is no threshold effect when the intensity of the tax incentive used as the threshold variable.

Physiotherapy as a health profession is continuously evolving in high-income countries (HIC). The highest burden of disease globally, however, is in low-resource and conflict contexts (LR-CC), resulting in unmet rehabilitation needs. Rehabilitation service models from HIC often face challenges when applied to the fragile health systems of LR-CC. It is important to engage rehabilitation experts living and working in LR-CC to guide service development. This study aims to understand physiotherapists’ views and perspectives of current rehabilitation services, of how these services can be strengthened over the next 10 years and of the role of physiotherapy within this development. Focus group discussions (FGDs) were conducted with 31 physiotherapists from 18 LR-CC using English as a common language. Audio recordings were transcribed verbatim. Data analysis was guided by thematic analysis. Participants provided deep insights into the complexity of developing rehabilitation services within fragile health systems. Participants agreed that physiotherapy lacked recognition and resources to be utilised effectively. Interacting themes as crucial prerequisites for strengthening the sector included (1) significance of context, (2) professional identity, and (3) professionalisation supported by workforce development and advocacy. These results are an important evidence base for informing the development of rehabilitation programmes in LR-CC and for future research.

National audience; This contribution examines the strain pattern of the Archean Ntem Complex,located in the northwestern part of the Congo Craton (southern Cameroon). We carrieda detailed field study coupled with aeromagnetic map for the two main greenstone belts(Sangmelima and Nyabisan), focusing on the geometry of structures as well askinematics, and identifying several lithological facies with distinct petrologicalcharacters. The time constraints of magmatism, metamorphism and deformation wereobtained by U–Pb LA–ICP–MS dating on zircon and EPMA U–Th–Pb dating onmonazite.The Nyabissan Greenstone Belt is dominated by sub-vertical transpressive shearzones with steeply plunging stretch lineations. There are vertical regional fabricdomains with sub- horizontal foliation domains suggesting a strain partitioning at aregional scale. Different generations of syntectonic mafic and felsic intrusions attest tolong-lasting progressive deformation.In the Sangmelima granite-greenstone belt (SGB), charnockites and TTG suites formedbetween~ 3155 and 2850 Ma. The gabbro intrusion was dated at 2866±6 Ma.Migmatization of the TTG-gneiss, coeval with a sub-horizontal shorteningsynmetamorphic D1 event, is dated around 2843–2820 Ma using U–Pb LA–ICP–MSon zircon and chemical U–Th–Pb EPMA dating on monazite. Syn-kinematicmonzogranite emplaced 2838±6 Ma ago. D2 is associated with the F2 folds and C2 shearzones coeval with the second anatexis period between ~2788–2722 Ma marked bythe emplacement of high-K granite that peaked at ~2750 Ma. Ages of migmatisationand syn-kinematic granites (2843 to 2722 Ma) suggest a long-lasting tectonic processin the Sangmelima area. Late Neoarchean granitic pegmatite/aplite dikes and/or veinsemplaced during the brittle deformation D3 and ANC protracted cooling between~2670–2550 Ma.A synthesis of all results leads to the reconstruction of the general structure for theNtem Complex, from the Paleo and Neoproterozoic to the Archean domains. Inaddition, a new model of Archean geodynamic evolution in the NW Congo Craton from3.32 Ga to 2.55 Ga is proposed.

International audience; The Sangmelima granite-greenstone belt (SGB) belongs to the Ntem Complex (NW Congo craton), and is represented by granite-gneiss terranes, granite-greenstone associations, mafic-ultramafic complexes, and mafic dyke swarms. Here, we present a new tectonic evolution model based on an aeromagnetic map, structural analysis, and geochronological data. Regional strain D1 is characterized by the development of steep foliations, steeply plunging lineations occasionally associated with vertical stretching of granitic dykes. D1 shear sense is top-toNNE oblique normal motion, inferred from the S 1 mylonitic fabric and the finite strain suggested that the vertical flow component dominates at the regional scale compared to the horizontal motions (Akame et al., 2020b). Syn-D1 melts, mineral assemblages and microstructures indicate that D1 took place under high-grade metamorphic conditions. D2 comprises deformation associated with sinistral strike slip and granitic dyke extractions. The C 2 shear zones are locally clogged by granitic melt and epidote-chlorite-biotite mineral recrystallizations, showing that the D2 transpressive deformation occurred from ductile to brittle conditions. The basement has thus been affected by a progressive D1-D2 strains induced by the bulk EW sub-horizontal shortening associated with vertical stretching in a transpressive tectonic style

International audience

Structural study of in the Sangmelima granite-greenstone terrains (SGB) provide a new overview of the evolution of the Ntem Complex (South Cameroon), the northwestern part of the Congo Craton. The regional deformation is marked by a strong steep dips foliation and steeply plunging mineral-stretching. D1-related structures are folding and shearing by a D2 deformation that is synchronous with extraction granitic dykes. D1–D2 structures were developed during regional E-W sub-horizontal shortening under ductile conditions associated with steeply dipping principal stretching in a transpressive regime, progressive strain localization along strike-slip shear zones. Syn-D1 mineral assemblages and high strain microstructures suggest that ductile deformation D1 occurred under high-grade metamorphic conditions, whereas D2 microstructures suggest a brittle deformation. The strain patterns in the SGB recorded a long-lasting Archean tectonic history within the Archean Ntem Complex (ca. 2.83–2.72Ga). Finally, some Archean structures were reactivated during a brittle deformation (D3), likely during the Eburnean event.

International audience; The Ntem Complex represents the northwestern margin of Congo Craton in southern Cameroon. It consists mainly of charnockites, TTG suites, potassic grantitoids, minor supracrustal and mafic rocks. The latter include gabbronorite enclave or sill, gabbro and dolerite dykes. The metagabbro are basaltic to andesitic in composition and show geochemical features of low-La Archean tholeiitic basalts, and LREE-depleted (LaN/SmN < 1) akin to modern N-MORB. The doleritic dykes show high TiO2/P2O5 (7.50–11.47) and (La/Yb)N ratios, and low NbTa values similar to modern intraplate continental basalts and intermediate-La Archean tholeiitic basalt, least affected by contamination from granitic continental crust. The partial melting of low-to high-K mafic rocks of oceanic and continental arc affinity generated the charnockites and low−/medium-pressure TTGs. The potassic granites were formed by partial melting of charnockite or TTG, and inherited many geochemical features of their sources. New LA–ICP–MS UPb zircon dates suggest that the charnockites and TTG suites formed at ~3155–2850 Ma. The gabbro intrusion was dated at 2866 ± 6 Ma. Migmatisation of TTG-gneiss was coeval whit the regional high–grade metamorphism event at 2843 ± 7 Ma. The potassic granites were probably crystallized at ~2758 Ma. The garnet-whole rock SmNd age of 2744 ± 31 Ma may represent the age of the second anatexis event coeval with D2 deformation. Literature data indicate the disruption or open isotopic systems in the Ntem Complex around 2500–2600 Ma.

International audience; The Sangmelima Greenstone Belt in southern Cameroon (NW Congo Craton) displays a D2 regional fabrics that consist of an S2 sub-vertical foliation, L2 stretching lineation and F2 folds resulting from a dextral transpressive regime. D3 late granulitic deformation synchronous with a migmatisation episode is characterized by F3 post-folds with oblique axes, sometimes associated with localized C3 shear zones showing inverse movements alongside an anatexy phenomenon. The plutons were emplaced during the regional deformation. The regional structure, combined with the existence of contemporary intrusive and extrusive rocks in the surface today, buttress a vertical tectonic model with burial of supra-crustal rocks in soft underlying material during the ENE-WSW to EW horizontal crustal shortening. The important magmatic intake within the craton allows a warming and a general softening of the lithosphere. Finally, CN has been affected by the Eburnean orogeny (D4), characterized by the development of the N40-60E transverse step with a generally sinusoidal component, to which some dextral conjugate bands are associated.

In the field of antimicrobial surfaces, the development of environmentally-friendly surface treatments and industrially viable processes remains a challenging research objective. The use of atmospheric plasma treatments, especially dielectric barrier discharge (DBD) plasma deposition, is a promising technological approach to confer a thin antibacterial coating to a surface. The aim of this work is to investigate the potentiality of atmospheric plasma polymer organosilicon-based coatings as a reactive layer for the immobilization of biologically active molecules on stainless steel surfaces. In this context, an atmospheric-pressure DBD afterglow is used for the first time to functionalize a steel surface with chemical groups in order to attach biomolecules and this process is compared with a direct DBD discharge. The organosilicon-containing plasma interlayer confers a silica-like skeleton to the coatings for adhesion and stability. Composition of the plasma films before and after peptide immobilization has been characterized by Fourier transform infrared spectroscopy (FTIR), static secondary ion mass spectrometry (TOF-SIMS) and X-ray photoelectron spectroscopy (XPS). It is shown that the covalent immobilization of the antibacterial nisin peptides onto the organosilicon interlayer leads to adherent and protective antibacterial coatings on stainless steel as demonstrated against Gram + bacteria using ISO 12296 antibacterial test. Nearly 4 log10 reduction of Gram + strain was obtained compared to uncoated stainless steel. Importantly the antibacterial surfaces were resistant to several cleaning conditions. The later is significant as the stability of such antibacterial surfaces in close to real life conditions is a major concern.

Peripartum cardiomyopathy (PPCM) is a life-threatening pregnancy-associated cardiomyopathy in previously healthy women. Although PPCM is driven in part by the 16-kDa N-terminal prolactin fragment (16K PRL), the underlying molecular mechanisms are poorly understood. We found that 16K PRL induced microRNA-146a (miR-146a) expression in ECs, which attenuated angiogenesis through downregulation of NRAS. 16K PRL stimulated the release of miR-146a-loaded exosomes from ECs. The exosomes were absorbed by cardiomyocytes, increasing miR-146a levels, which resulted in a subsequent decrease in metabolic activity and decreased expression of Erbb4, Notch1, and Irak1. Mice with cardiomyocyte-restricted Stat3 knockout (CKO mice) exhibited a PPCM-like phenotype and displayed increased cardiac miR-146a expression with coincident downregulation of Erbb4, Nras, Notch1, and Irak1. Blocking miR-146a with locked nucleic acids or antago-miRs attenuated PPCM in CKO mice without interrupting full-length prolactin signaling, as indicated by normal nursing activities. Finally, miR-146a was elevated in the plasma and hearts of PPCM patients, but not in patients with dilated cardiomyopathy. These results demonstrate that miR-146a is a downstream-mediator of 16K PRL that could potentially serve as a biomarker and therapeutic target for PPCM.

International audience; Despite impressive successes in protein design, designing a well-folded protein of more 100 amino acids de novo remains a formidable challenge. Exploiting the promising biophysical features of the artificial protein Octarellin V, we improved this protein by directed evolution, thus creating a more stable and soluble protein: Octarellin V.1. Next, we obtained crystals of Octarellin V.1 in complex with crystallization chaperons and determined the tertiary structure. The experimental structure of Octarellin V.1 differs from its in silico design: the (αβα) sandwich architecture bears some resemblance to a Rossman-like fold instead of the intended TIM-barrel fold. This surprising result gave us a unique and attractive opportunity to test the state of the art in protein structure prediction, using this artificial protein free of any natural selection. We tested 13 automated webservers for protein structure prediction and found none of them to predict the actual structure. More than 50% of them predicted a TIM-barrel fold, i.e. the structure we set out to design more than 10years ago. In addition, local software runs that are human operated can sample a structure similar to the experimental one but fail in selecting it, suggesting that the scoring and ranking functions should be improved. We propose that artificial proteins could be used as tools to test the accuracy of protein structure prediction algorithms, because their lack of evolutionary pressure and unique sequences features.

The pituitary is a complex gland comprising different cell types each secreting specific hormones. The extensive network of signaling molecules and transcription factors required for determination and terminal differentiation of specific cell types is still not fully understood. The SRY-like HMG-box (SOX) transcription factor Sox4 plays important roles in many developmental processes and has two homologs in zebrafish, Sox4a and Sox4b. We show that the sox4b gene is expressed in the pituitary anlagen starting at 24 h after fertilization (hpf) and later in the entire head region including the pituitary. At 48 hpf, sox4b mRNA colocalizes with that for TSH (tshβ), glycoprotein subunit α (gsuα), and the Zn finger transcription factor Gata2a. Loss of Sox4b function, using morpholino knockdown or expression of a dominant-negative Sox4 mutant, leads to a drastic decrease in tshβ and gsuα expression and reduced levels of gh, whereas other anterior pituitary gland markers including prl, slβ, pomc, and lim3 are not affected. Sox4b is also required for expression of gata2a in the pituitary. Knockdown of gata2a leads to decreased tshβ and gsuα expression at 48 hpf, similar to sox4b morphants. Injection of gata2a mRNA into sox4b morphants rescued tshβ and gsuα expression in thyrotrope cells. Finally, sox4b or gata2a knockdown causes a significant decrease of gonadotropin expression (lhβ and fshβ) at 4 d after fertilization. In summary, our results indicate that Sox4b is expressed in zebrafish during pituitary development and plays a crucial role in the differentiation of thyrotrope and gonadotrope cells through induction of gata2a expression in the developing pituitary.

The goal of this paper was to establish the durability profile of antibacterial multilayer thin films under storage and usage conditions. Thin films were built on stainless steel (SS) by means of a layer-by-layer process alternating a negatively charged polyelectrolyte, polyacrylic acid, with a cationic antibacterial peptide, nisin. SS coupons coated with the antibacterial film were challenged under environmental and usage conditions likely to be encountered in real-world applications. The change in antibacterial activity elicited by the challenge was used as an indicator of multilayer film resistance. Antibacterial SS samples could be stored for several weeks at 4°C in ambient air and antibacterial films were resistant to dipping and mild wiping in water and neutral detergent. The multilayer coating showed some weaknesses, however, that need to be addressed.

The 16-kDa angiostatic N-terminal fragment of human prolactin (16K hPRL) has been reported to be a new potent anticancer compound. This protein has already proven its efficiency in several mouse tumor models in which it prevented tumor-induced angiogenesis and delayed tumor growth. In addition to angiogenesis, tumors also stimulate the formation of lymphatic vessels, which contribute to tumor cell dissemination and metastasis. However, the role of 16K hPRL in tumor-induced lymphangiogenesis has never been investigated. We establish in vitro that 16K hPRL induces apoptosis and inhibits proliferation, migration, and tube formation of human dermal lymphatic microvascular endothelial cells. In addition, in a B16F10 melanoma mouse model, we found a decreased number of lymphatic vessels in the primary tumor and in the sentinel lymph nodes after 16K hPRL treatment. This decrease is accompanied by a significant diminished expression of lymphangiogenic markers in primary tumors and sentinel lymph nodes as determined by quantitative RT-PCR. These results suggest, for the first time, that 16K hPRL is a lymphangiostatic as well as an angiostatic agent with antitumor properties.

This paper highlights an innovative application of inorganic-binding peptides as quality control tools for detecting defects on inorganic surfaces of any shape. The approach involves attaching a fluorescent label to an inorganic-binding peptide and exploiting the peptide's high binding specificity to detect, by simple fluorescence microscopy, chemical composition defects of microm size and crystallographic state defects. Proof of concept was demonstrated by monitoring binding of a previously isolated ZnO-binding peptide to galvanized steel substrates. The approach was further validated for TiO(2) coatings and stainless steel, with two new, specific inorganic-binding peptides isolated by phage display.

Microorganisms are able to attach to, grow on, and ultimately form biofilms on a large variety of surfaces, such as industrial equipment, food contact surfaces, medical implants, prostheses and operating rooms. Once organized into biofilms, bacteria are difficult to remove and kill, which increases the risk of cross-contamination and infection. One way to address the problem may thus be to develop antibacterial, anti-adhesion, 'easy cleaning' surfaces. In this study, stainless steel (SS) surfaces with antibacterial properties were created by embedding several antimicrobial peptides in a multilayer film architecture. The biocidal effect of these surfaces was demonstrated against both Gram-positive and Gram-negative bacteria according to two ISO tests. Also, coating SS surfaces with either mucin or heparin led to a reduction of S. epidermidis adhesion of almost 95% vs the bare substratum. Finally, by combining both antibacterial and anti-adhesion biomolecules in the same multilayer film, SS surfaces with better cleanability were produced. This surface coating property may help to delay the buildup of a dead bacterial layer which is known to progressively reduce exposure of the coating, leading to an undesirable decrease in the antibacterial effect of the surface.

In mice, the Nkx6 genes are crucial to alpha- and beta-cell differentiation, but the molecular mechanisms by which they regulate pancreatic subtype specification remain elusive. Here it is shown that in zebrafish, nkx6.1 and nkx6.2 are co-expressed at early stages in the first pancreatic endocrine progenitors, but that their expression domains gradually segregate into different layers, nkx6.1 being expressed ventrally with respect to the forming islet while nkx6.2 is expressed mainly in beta-cells. Knockdown of nkx6.2 or nkx6.1 expression leads to nearly complete loss of alpha-cells but has no effect on beta-, delta-, or epsilon-cells. In contrast, nkx6.1/nkx6.2 double knockdown leads additionally to a drastic reduction of beta-cells. Synergy between the effects of nkx6.1 and nkx6.2 knockdown on both beta- and alpha-cell differentiation suggests that nkx6.1 and nkx6.2 have the same biological activity, the required total nkx6 threshold being higher for alpha-cell than for beta-cell differentiation. Finally, we demonstrate that the nkx6 act on the establishment of the pancreatic endocrine progenitor pool whose size is correlated with the total nkx6 expression level. On the basis of our data, we propose a model in which nkx6.1 and nkx6.2, by allowing the establishment of the endocrine progenitor pool, control alpha- and beta-cell differentiation.

Pax6 is a well conserved transcription factor that contains two DNA-binding domains, a paired domain and a homeodomain, and plays a key role in the development of eye, brain, and pancreas in vertebrates. The recent identification of the zebrafish sunrise mutant, harboring a mutation in the pax6b homeobox and presenting eye abnormalities but no obvious pancreatic defects, raised a question about the role of pax6b in zebrafish pancreas. We show here that pax6b does play an essential role in pancreatic endocrine cell differentiation, as revealed by the phenotype of a novel zebrafish pax6b null mutant and of embryos injected with pax6b morpholinos. Pax6b-depleted embryos have almost no beta cells, a strongly reduced number of delta cells, and a significant increase of epsilon cells. Through the use of various morpholinos targeting intron-exon junctions, pax6b RNA splicing was perturbed at several sites, leading either to retention of intronic sequences or to deletion of exonic sequences in the pax6b transcript. By this strategy, we show that deletion of the Pax6b homeodomain in zebrafish embryos does not disturb pancreas development, whereas lens formation is strongly affected. These data thus provide the explanation for the lack of pancreatic defects in the sunrise pax6b mutants. In addition, partial reduction of Pax6b function in zebrafish embryos performed by injection of small amounts of pax6b morpholinos caused a clear rise in alpha cell number and in glucagon expression, emphasizing the importance of the fine tuning of the Pax6b level to its biological activity.

Sox7 and Sox18 are members of the F-subgroup of Sox transcription factors family and are mostly expressed in endothelial compartments. In humans, dominant mutations in Sox18 are the underlying cause of the severe hypotrichosis–lymphedema–telangiectasia disorder characterized by vascular defects. However little is known about which vasculogenic processes Sox7 and Sox18 regulate in vivo. We cloned the orthologs of Sox7 and Sox18 in zebrafish, analysed their expression pattern and performed functional analyses. Both genes are expressed in the lateral plate mesoderm during somitogenesis. At later stages, Sox18 is expressed in all axial vessels whereas Sox7 expression is mainly restricted to the dorsal aorta. Knockdown of Sox7 or Sox18 alone failed to reveal any phenotype. In contrast, blocking the two genes simultaneously led to embryos displaying dysmorphogenesis of the proximal aorta and arteriovenous shunts, all of which can account for the lack of circulation observed in the trunk and tail. Gene expression analyses performed with general endothelial markers on double morphants revealed that Sox7 and Sox18 are dispensable for the initial specification and positioning of the major trunk vessels. However, morphants display ectopic expression of the venous Flt4 marker in the dorsal aorta and a concomitant reduction of the artery-specific markers EphrinB2a and Gridlock. The striking similarities between the phenotype of Sox7/Sox18 morphants and Gridlock mutants strongly suggest that Sox7 and Sox18 control arterial–venous identity by regulating Gridlock expression.

Tumor metastases, the most fearsome aspect of cancer, are generally resistant to conventional therapies. Angiogenesis is a crucial aspect of tumor growth and metastatic dissemination. Antiangiogenic therapy, therefore, holds potential as an attractive strategy for inhibiting metastasis development. Human 16K PRL (16K hPRL), a potent inhibitor of angiogenesis, has been demonstrated to prevent tumor growth in two xenograft mouse models, but whether it also affects tumor metastasis is unknown. In this study we will investigate the ability of 16K hPRL to prevent the establishment of metastasis. We demonstrate that 16K hPRL administered via adenovirus-mediated gene transfer, inhibits tumor growth by 86% in a subcutaneous (SC) B16-F10 mouse melanoma model. Computer-assisted image analysis shows that 16K hPRL treatment results in a reduction of tumor-vessel length and width, leading to a 57% reduction of average vessel size. In a pre-established tumor model, moreover, 16K hPRL can significantly delay tumor development. Finally, for the first time, we provide evidence that 16K hPRL considerably reduces the establishment of B16-F10 metastasis in an experimental lung metastasis model. Both the number and size of metastases are reduced by 50% in 16K hPRL-treated mice. These results highlight a potential role for 16K hPRL in anticancer therapy for both primary tumors and metastases.

In amniotes, the pancreatic mesenchyme plays a crucial role in pancreatic epithelium growth, notably through the secretion of fibroblast growth factors. However, the factors involved in the formation of the pancreatic mesenchyme are still largely unknown. In this study, we characterize, in zebrafish embryos, the pancreatic lateral plate mesoderm, which is located adjacent to the ventral pancreatic bud and is essential for its specification and growth. We firstly show that the endoderm, by expressing the fgf24 gene at early stages, triggers the patterning of the pancreatic lateral plate mesoderm. Based on the expression of isl1, fgf10 and meisgenes, this tissue is analogous to the murine pancreatic mesenchyme. Secondly,Fgf10 acts redundantly with Fgf24 in the pancreatic lateral plate mesoderm and they are both required to specify the ventral pancreas. Our results unveil sequential signaling between the endoderm and mesoderm that is critical for the specification and growth of the ventral pancreas, and explain why the zebrafish ventral pancreatic bud generates the whole exocrine tissue.

In the corpus luteum (CL), blood vessels develop, stabilize, and regress. This process depends on the ratio of pro- and antiangiogenic factors, which change during the ovarian cycle. The present study focuses on the possible roles of 23,000 (23K) prolactin (PRL) in the bovine CL and its antiangiogenic NH2-terminal fragments after extracellular cleavage by cathepsin D (Cath D). PRL RNA and protein were demonstrated in the CL tissue, in luteal endothelial cells, and in steroidogenic cells. Cath D was detected in CL tissue, cell extracts, and corresponding cell supernatants. In the intact CL, 23K PRL levels decreased gradually, whereas Cath D levels concomitantly increased between early and late luteal stages. In vitro, PRL cleavage occurred in the presence of acidified homogenates of CL tissue, cells, and corresponding cell supernatants. Similar fragments were obtained with purified Cath D, and their appearance was inhibited by pepstatin A. The aspartic protease specific substrate MOCAc-GKPILF∼FRLK(Dnp)-d- R-NH2was cleaved by CL cell supernatants, providing further evidence for Cath D activity. The 16,000 PRL inhibited proliferation of luteal endothelial cells accompanied by an increase in cleaved caspase-3. In conclusion, 1) the bovine CL is able to produce PRL and to process it into antiangiogenic fragments by Cath D activity and 2) PRL cleavage might mediate angioregression during luteolysis.

The capillary counterdiffusion method is a very efficient crystallization technique for obtaining high-quality protein crystals. This technique requires a convection-free environment, which can be achieved using either gelled solutions, very thin capillaries, or microgravity conditions. To study the influence of a convection-free environment on protein crystal quality and to evaluate two different experimental implementations to achieve it, we have made a comparative analysis of crystals grown by capillary counterdiffusion in agarose, a convective-free environment on Earth, and crystals grown in microgravity at the International Space Station. Thermotoga maritima triose phosphate isomerase (TIM) was chosen as a model for this study. The statistical analysis reveals a significant improvement for the crystals grown in microgravity in terms of their R-merge, B-value, and mosaicity, but the statistical evidence is insufficient to show a similar benefit for the resolution and mean intensity parameters. These results are quite surprising because it is known that, unlike gels, the noisy microgravity scenario offered by the ISS cannot sustain a convection-free environment on the time scale of days required for protein crystallization experiments.

In endothelial cells, binding of vascular endothelial growth factor (VEGF) to the receptor VEGFR2 activates multiple signaling pathways that trigger processes such as proliferation, survival, and migration that are necessary for angiogenesis. VEGF-bound VEGFR2 becomes internalized, which is a key step in the proangiogenic signal. We showed that the urokinase plasminogen activator receptor (uPAR) interacted with VEGFR2 and described the mechanism by which this interaction mediated VEGF signaling and promoted angiogenesis. Knockdown of uPAR in human umbilical vein endothelial cells (HUVECs) impaired VEGFR2 signaling, and uPAR deficiency in mice prevented VEGF-induced angiogenesis. Upon exposure of HUVECs to VEGF, uPAR recruited the low-density lipoprotein receptor-related protein 1 (LRP-1) to VEGFR2, which induced VEGFR2 internalization. Thus, the uPAR-VEGFR2 interaction is crucial for VEGF signaling in endothelial cells.

Angiogenesis is a crucial step in many pathologies, including tumor growth and metastasis. Here, we show that tilted peptides exert antiangiogenic activity. Tilted (or oblique-oriented) peptides are short peptides known to destabilize membranes and lipid cores and characterized by an asymmetric distribution of hydrophobic residues along the axis when helical. We have previously shown that 16-kDa fragments of the human prolactin/growth hormone (PRL/GH) family members are potent angiogenesis inhibitors. Here, we demonstrate that all these fragments possess a 14-aa sequence having the characteristics of a tilted peptide. The tilted peptides of human prolactin and human growth hormone induce endothelial cell apoptosis, inhibit endothelial cell proliferation, and inhibit capillary formation both in vitro and in vivo . These antiangiogenic effects are abolished when the peptides' hydrophobicity gradient is altered by mutation. We further demonstrate that the well known tilted peptides of simian immunodeficiency virus gp32 and Alzheimer's β-amyloid peptide are also angiogenesis inhibitors. Taken together, these results point to a potential new role for tilted peptides in regulating angiogenesis.

The cristallisation by counterdiffusion is a very efficient technique for obtaining high-quality protein crystals. A prerequisite for the use of counterdiffusion techniques is that mass transport must be controlled by diffusion alone. Sedimentation and convection can be avoided by either working in gelled systems, working in systems of small dimensions, or in the absence of gravity. We present the results from experiments performed on the ISS using the Protein Microscope for the International Space Station (PromISS), using digital holography to visualise crystal growth processes. We extensively characterised three model proteins for these experiments (cablys3*lysozyme, triose phosphate isomerase, and parvalbumin) and used these to assess the ISS as an environment for crystallisation by counterdififusion. The possibility to visualise growth and movement of crystals in different types of experiments (capillary counterdiffusion and batch-type) is important, as movement of crystals is clearly not negligible.