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Activated complement component C4 (C4b) is the nonenzymatic component of the classical pathway (CP) convertases of the complement system. Preparation of C4 and C4b samples suitable for structural biology studies is challenging due to low yields and complexity of recombinant C4 production protocols reported so far and heterogeneity of C4 in native sources. Here we present a purification protocol for human C4 and describe sample preparation methods for structural investigation of C4 and its complexes by crystallography, small angle X-ray scattering, and electron microscopy.

Laboratory Adaptive Optics (AO) benches are the backbone of experimental testing and verification of new AO designs and architectures. These testbeds are particularly important when exploring unknown factors in the development of new instruments and facilities like future extremely large telescope AO systems. One of the key elements for simulating the performance of such systems in a smaller scale laboratory environment is the ability of projecting the precise intensity mask on the pupil plane. This mask often has binary (black or transparent/reflective) patterns that mimic the secondary obscuration and spider design of the telescope. Precise implementation of such intensity masks on the bench is important since studying effects such as “island/petaling effect” are critically dependent on the correct down-scaling and precise representation of the spider structure. Using a physical mask for such an application is very difficult since manufacturing and installing such fine structure pieces are difficult and hard to use. It is also necessary to build a new physical mask for each telescope system or scale that is desired for the experiment. In this paper, we introduce two methods of using a phase only Liquid Crystal on Silicon Spatial Light Modulator (LCoS-SLM) device as an alternative option to precisely and relatively easily inject the custom intensity mask into an optical bench. By implementing these methods on the LOOPS bench AO facilities of the LAM, we demonstrated that the contrast produced by both methods could be better than 2% (dark/bright ratio), which is sufficient for representing pupil obscuration in the majority of applications. We also show that by using one of these methods, it is possible to inject phase and binary intensity mask simultaneously which could greatly increase the versatility and ease of use of an experimental AO setup., Adaptive Optics Systems VII, December 14-18, 2020, Online Only, United States, Series: Proceedings of SPIE

IRIS is a diffraction limited instrument designed for first light of the Thirty Meter Telescope (TMT). It combines a nearinfrared integral field spectrograph (lenslet array and mirror slicer) and a wide-field imager with platescales as small as 4 mas. The project is nearing the end of its final design phase and will soon be ready for fabrication. Our team has created a wide variety of prototypes and design solutions for this advanced instrument. While many challenges like atmospheric dispersion correction and saturation are particularly acute due to the telescope diameter, many others arise from the large format detector arrays and wide range of science goals. We’ll present the overall design, results from our prototyping activities and discuss the astrophysical opportunities., Ground-based and Airborne Instrumentation for Astronomy VIII, December 14-18, 2020, Online Only, United States, Series: Proceedings of SPIE

Most proteins in the α-macroglobulin (αM) superfamily contain reactive thiol esters that are required for their biological function. Here, we have characterized the human α2-macroglobulin (A2M) and complement component C3 mutants A2M Q975C and C3 Q1013C, which replace the CGEQ thiol ester motifs of the original proteins with the disulfide-forming sequence CGEC. Mass spectrometry showed that the intended disulfide was formed in both proteins. The correct folding and native conformation of A2M Q975C were shown by its assembly to a tetramer, an initially slow electrophoretic mobility with a demonstrable conformational collapse induced by proteolysis, functional protease trapping, and conformation-dependent interactions with low-density lipoprotein receptor-related protein 1. However, A2M Q975C had a decreased capacity to inhibit trypsin and was more susceptible to cleavage by trypsin or thermolysin when compared to wild-type A2M. C3 Q1013C also folded correctly and was initially in a native conformation, as demonstrated by its cation exchange elution profile, electrophoretic mobility, and interaction with complement factor B, although it assumed a conformation that was distinct from native C3, C3b, or C3(H2O) when cleaved by trypsin. These results demonstrate that disulfides can substitute thiol esters and maintain the native conformations of A2M and C3. Additionally, they indicate that proteolysis is not the sole factor in the conformational changes of A2M and C3 and that thiol ester lysis also plays a role.

Limited information exists on the clinical behavior of the Ewing sarcoma family of tumors (ESFT) of the kidney. We reviewed the records of 30 patients (aged 8&ndash, 69 years) with ESFT of the kidney seen at our institution between 1990 and 2013. We analyzed the event-free survival (EFS) and overall survival (OS) for associations with patient demographics, disease group, tumor size, tumor thrombus, and treatment. Six patients (20%) had tumors confined to the kidney (Group I), seven (23.3%) had local tumor extension beyond the kidney (Group II), and 17 (56.7%) had distant metastasis at diagnosis (Group III). Twenty-five (83.3%) patients underwent radical (19 upfront, five delayed) or partial (one upfront) nephrectomy, 25 (83.3%) chemotherapy and four (13.3%) radiotherapy. The 4-year EFS and OS were 43% (95% CI, 26&ndash, 61%) and 63% (95% CI, 46&ndash, 81%), respectively. EFS and OS were significantly associated with disease group and chemotherapy (p &lt, 0.039). The presence of tumor thrombus in renal vein and/or inferior vena cava was associated with worse EFS (p = 0.053). Patients with disease confined to the kidney treated with nephrectomy and adjuvant chemotherapy have favorable outcomes. Local tumor extension beyond the kidney, tumor thrombus, and distant metastasis are unfavorable factors that warrant intensification or novel approaches of therapy.

Background: Pediatric, adolescent and young adult (PAYA) patients are less active than their healthy counterparts, particularly during inpatient stays. Methods: We conducted a quality improvement initiative to increase activity levels in patients admitted to our pediatric oncology and cellular therapy unit using a Plan-Do-Study-Act (PDSA) model. An interdisciplinary team was assembled to develop an incentive-based inpatient exercise and activity program titled Totally Excited About Moving Mobility and Exercise (TEAM Me). As part of the program, patients were encouraged by their care team to remain active during their inpatient stay. As an additional incentive, patients earned stickers to display on TEAM Me door boards along with tickets that could be exchanged for prizes. Activity was assessed by documentation of physical therapy participation, tests of physical function, and surveys of staff perceptions of patient activity levels, motivations, and barriers. Results: Compared to baseline, patient refusals to participate in physical therapy decreased significantly (24% vs. 2%) (p < 0.02), and staff perceptions of patient motivation to stay active increased from 40% to 70% in the post implementation period. There were no changes in physical function tests. Conclusions: An incentive-based exercise program for young oncology inpatients greatly improved patient activity levels, participation in physical therapy and influenced professional caregivers’ beliefs.

Acta crystallographica / D 73(10), 804 - 813 (2017). doi:10.1107/S2059798317013171, The generation of high-quality protein crystals and the loss of phase information during an X-ray crystallography diffraction experiment represent the major bottlenecks in the determination of novel protein structures. A generic method for introducing Hg atoms into any crystal independent of the presence of free cysteines in the target protein could considerably facilitate the process of obtaining unbiased experimental phases. Nanobodies (single-domain anti­bodies) have recently been shown to promote the crystallization and structure determination of flexible proteins and complexes. To extend the usability of nanobodies for crystallographic work, variants of the Nb36 nanobody with a single free cysteine at one of four framework-residue positions were developed. These cysteines could be labelled with fluorophores or Hg. For one cysteine variant (Nb36-C85) two nanobody structures were experimentally phased using single-wavelength anomalous dispersion (SAD) and single isomorphous replacement with anomalous signal (SIRAS), taking advantage of radiation-induced changes in Cys–Hg bonding. Importantly, Hg labelling influenced neither the interaction of Nb36 with its antigen complement C5 nor its structure. The results suggest that Cys–Hg-labelled nanobodies may become efficient tools for obtaining de novo phase information during the structure determination of nanobody–protein complexes., Published by Wiley-Blackwell, Oxford

To investigate acute changes in biochemical markers of bone and cartilage turnover in response to moderate intensity exercise with and without joint impact in healthy human subjects.A randomized, cross-over, exploratory, clinical study was conducted. Twenty healthy subjects with no history of joint trauma completed 30 min interventions of standardized moderate intensity cycling and running as well as a resting intervention 1 week apart. Blood samples were taken immediately before, four times after exercise and again the next day. Urine was sampled, before, after and the next day. On the day of rest, samples were taken at timepoints similar to the days of exercise. Markers of type I (CTX-I), II (C2M, CTX-II) and VI (C6M) collagen degradation, cartilage oligomeric matrix protein (COMP) and procollagen C-2 (PRO-C2) was measured.NCT04542655, 02 September 2020, retrospectively registered.CTX-I was different from cycling (4.2%, 95%CI: 0.4-8.0%, p = 0.03) and resting (6.8%, 95%CI: 2.9-10.7%, p = 0.001) after running and the mean change in COMP was different from cycling (10.3%, 95%CI: 1.1-19.5%, p = 0.03), but not from resting (8.6%, 95%CI: - 0.7-17.8%, p = 0.07) after running. Overall, changes in other biomarkers were not different between interventions.In this exploratory study, running, but not cycling, at a moderate intensity and duration induced acute changes in biomarkers of bone and cartilage extra-cellular matrix turnover.

Switching perception of friend and foe Lysine motif receptors in plants perceive glycans that signal the presence of pathogenic or symbiotic nitrogen-fixing microbes. Bozsoki et al. now define the portions of these receptors that create the discriminatory binding pocket (see the Perspective by Bisseling and Geurts). The motifs were conserved in receptors that initiate immune responses, reflecting the invariable nature of the chitin fragments that they sense. Conversely, the motifs in receptors that respond to symbiotic signals were more varied, reflecting the greater diversity of the lipochitooligosaccharides (Nod factors) that they sense. With domain swapping, the authors switched the Nod factor specificity of receptors from two legume species and also enabled a chitin receptor that was otherwise dedicated to the detection of pathogenic microbes to instead recognize Nod factors. Science , this issue p. 663 ; see also p. 620

Some human antibodies may paradoxically inhibit complement activation on bacteria and enhance pathogen survival in humans. This property was also claimed for IgG antibodies reacting with terminal galactose‐α‐1,3‐galactose (Galα3Gal; IgG anti‐αGal), a naturally occurring and abundant antibody in human plasma that targets numerous different pathogens. To reinvestigate these effects, we used IgG anti‐αGal affinity isolated from a pool of normal human IgG and human hypogammaglobulinaemia serum as a complement source. Flow cytometry was performed to examine antibody binding and complement deposition on pig erythrocytes, Escherichia coli O86 and Streptococcus pneumoniae serotype 9V. Specific nanobodies were used to block the effect of single complement factors and to delineate the complement pathways involved. IgG anti‐αGal was capable of activating the classical complement pathway on all the tested target cells. The degree of activation was exponentially related to the density of bound antibody on E. coli O86 and pig erythrocytes, but more linearly on S. pneumoniae 9V. The alternative pathway of complement amplified complement deposition. Deposited C3 fragments covered the activating IgG anti‐αGal, obstructing its detection and highlighting this as a likely general caveat in studies of antibody density and complement deposition. The inherent capacity for complement activation by the purified carbohydrate reactive IgG anti‐αGal was similar to that of normal human IgG. We propose that the previously reported complement inhibition by IgG anti‐αGal relates to suboptimal assay configurations, in contrast to the complement activating property of the antibodies demonstrated in this paper.

Summary ParagraphMosquito-borne viruses have recently spread globally, with major impacts on human health. Zika virus (ZIKV) emerged from obscurity in 2013 to spread from Asia to the South Pacific and the Americas, where millions of people were infected. For the first time, severe clinical manifestations, including Guillain Barré syndrome and defects to the fetuses of pregnant women, were detected. Phylogenetic studies have shown that ZIKV evolved in Africa and later spread to Asia, and that the Asian lineage is responsible for the recent epidemics. However, the reasons for the sudden emergence of ZIKV remain incompletely understood. Accumulating evidence on other arboviruses like chikungunya and West Nile suggest the likelihood that viral mutations could be determinants of change in ZIKV transmission efficiency responsible for efficient spread. Using evolutionary analyses, we determined that four mutations, which occurred just before ZIKV introduction to the Americas, represent direct reversions of previous mutations that accompanied spread many decades ago from ZIKV’s native Africa to Asia and early circulation there. Experimental infections of mosquitoes, human cells, and mice using ZIKV strains with and without these mutations demonstrated that the original mutations reduced fitness for urban transmission, while the reversions restored fitness, increasing epidemic risk. Overall, our findings include the three newly identified, transmission-adaptive ZIKV mutations, and demonstration that these and one identified previously restored fitness for epidemic transmission soon before introduction into the America. The initial mutations may have followed founder effects and/or drift when the virus was introduced into Asia, or could be related to changes on host or vector utilization within Asia.

The severity of burn and smoke inhalation-induced acute lung injury (BSI-ALI) is associated with alveolar and interstitial edema, bronchospasm, and airway mucosal hyperemia. Previously, we have reported beneficial effects of epinephrine nebulization on BSI-ALI. However, the underlying mechanisms of salutary effects of nebulized epinephrine remain unclear. The present study compared the effects of epinephrine, phenylephrine, and albuterol on a model of BSI-ALI. We tested the hypothesis that both α1- and β2-agonist effects are required for ameliorating more efficiently the BSI-ALI. Forty percent of total body surface area, 3rd-degree cutaneous burn, and 48-breaths of cotton smoke inhalation were induced to 46 female Merino sheep. Postinjury, sheep were mechanically ventilated and cardiopulmonary hemodynamics were monitored for 48 h. Sheep were allocated into groups: control, n = 17; epinephrine, n = 11; phenylephrine, n = 6; and albuterol, n = 12. The drug nebulization began 1 h postinjury and was repeated every 4 h thereafter. In the results, epinephrine group significantly improved oxygenation compared to other groups, and significantly reduced pulmonary vascular permeability index, lung wet-to-dry weight ratio, and lung tissue growth factor-β1 level compared with albuterol and control groups. Epinephrine and phenylephrine groups significantly reduced trachea wet-to-dry weight ratio and lung vascular endothelial growth factor-A level compared with control group. Histopathologically, epinephrine group significantly reduced lung severity scores and preserved vascular endothelial-cadherin level in pulmonary arteries. In conclusion, the results of our studies suggest that nebulized epinephrine more effectively ameliorated the severity of BSI-ALI than albuterol or phenylephrine, possibly by its combined α1- and β2-agonist properties.

The complement system is an intricate cascade of the innate immune system and plays a key role in microbial defense, inflammation, organ development, and tissue regeneration. There is increasing interest in developing complement regulatory and inhibitory agents to treat complement dysfunction. In this study, we describe the nanobody hC3Nb3, which is specific for the C-terminal C345c domain of human and mouse complement component C3/C3b/C3c and potently inhibits C3 cleavage by the alternative pathway. A high-resolution structure of the hC3Nb3–C345c complex explains how the nanobody blocks proconvertase assembly. Surprisingly, although the nanobody does not affect classical pathway–mediated C3 cleavage, hC3Nb3 inhibits classical pathway–driven hemolysis, suggesting that the C-terminal domain of C3b has an important function in classical pathway C5 convertase activity. The hC3Nb3 nanobody binds C3 with low nanomolar affinity in an SDS-resistant complex, and the nanobody is demonstrated to be a powerful reagent for C3 detection in immunohistochemistry and flow cytometry. Overall, the hC3Nb3 nanobody represents a potent inhibitor of both the alternative pathway and the terminal pathway, with possible applications in complement research, diagnostics, and therapeutics.

Nuclear pore complexes (NPCs) are the main conduits for molecular exchange across the nuclear envelope. The NPC is a modular assembly of ~500 individual proteins, called nucleoporins or nups. Most scaffolding nups are organized in two multimeric subcomplexes, the Nup84 or Y complex and the Nic96 or inner ring complex. Working in S. cerevisiae, and to study the assembly of these two essential subcomplexes, we here develop a set of twelve nanobodies that recognize seven constituent nucleoporins of the Y and Nic96 complexes. These nanobodies all bind specifically and with high affinity. We present structures of several nup-nanobody complexes, revealing their binding sites. Additionally, constitutive expression of the nanobody suite in S. cerevisiae detect accessible and obstructed surfaces of the Y complex and Nic96 within the NPC. Overall, this suite of nanobodies provides a unique and versatile toolkit for the study of the NPC., Characterizing the assembly of the nuclear pore complex (NPC) remains challenging. Here, the authors develop a set of nanobodies that recognize seven constituent nucleoporins, study their binding characteristics, and apply them to probe accessible and obstructed NPC surfaces in yeast.

This paper discusses the impacts of large voltage drops on very long HVDC transmission lines, especially when operating in a monopolar mode. The effect of using dedicated metallic return (DMR) conductors is discussed. The main focus is on the potential rise at the neutral point of the converters and the need for an increased range for the converter transformer tap changers. Two grounding schemes for multiterminals transnational HVDC systems are presented: single point low impedance grounding and high impedance multi-point grounding. The advantages of the high impedance scheme are discussed. An innovative compensation method for voltage drop effects using a series HVDC converter is presented along with simulation results. The novel series converter can address both issues of neutral voltage rise and the impractical tap changer range. To put the ideas into the perspective, a realistic example of a transnational HVDC connecting China, central Asia, Russia and West Europe is presented.

The complement system is a tightly controlled proteolytic cascade in the innate immune system, which tags intruding pathogens and dying host cells for clearance. An essential protein in this process is complement component C3. Uncontrolled complement activation has been implicated in several human diseases and disorders and has spurred the development of therapeutic approaches that modulate the complement system. Here, using purified proteins and several biochemical assays and surface plasmon resonance, we report that our nanobody, hC3Nb2, inhibits C3 deposition by all complement pathways. We observe that the hC3Nb2 nanobody binds human native C3 and its degradation products with low nanomolar affinity and does not interfere with the endogenous regulation of C3b deposition mediated by Factors H and I. Using negative-stain EM analysis and functional assays, we demonstrate that hC3Nb2 inhibits the substrate-convertase interaction by binding to the MG3 and MG4 domains of C3 and C3b. Furthermore, we notice that hC3Nb2 is cross-reactive and inhibits the lectin and alternative pathway in murine serum. We conclude that hC3Nb2 is a potent, general, and versatile inhibitor of the human and murine complement cascades. Its cross-reactivity suggests that this nanobody may be valuable for analysis of complement activation within animal models of both acute and chronic diseases.

Shortage in autograft to cover burn wounds involves a frequent use of cadaver skin (CS) as a temporary cover to prevent infection, dehydration and preparation of wounds for subsequent autografting. We aimed to establish an ovine model of burn wound healing using ovine CS (OCS). Quality and efficacy of fresh and frozen OCS overlaid on to excised 3rd degree flame burn wounds in sheep were evaluated in comparison to autograft. Histologically, autografted wounds maintained normal skin structure at different time points. Wounds overlaid with fresh OCS graft showed signs of rejection starting from day 7. At day 14, the epidermis was mostly rejected. The rejection was completed by day 20 with signs of immunoreaction and presence of many immune cells. Frozen OCS was rejected in the same pattern. Immediately prior to grafting, the thickness was comparable between freshly prepared and frozen OCS for 10 or 40 days. Significant reduction in viability was detected in OCS frozen for 40 days. Both fresh or frozen ovine OCS were rejected within 10 days that mimics CS rejection time in humans (∼8.4 days), suggesting that ovine model of burn wound grafted with OCS can successfully be used in burn wound research mimicking clinical scenario.

Chemically modified antigen-binding proteins are widely applied for their targeting abilities in the fields of biotechnology, medicine, and diagnostics. However, the production of site-selectively modified proteins remains a challenge. Here, we have designed a chemical probe for the introduction of a reactive aldehyde on nanobodies by metal-complex-guided conjugation. The probe design allows for purification of the conjugates, and the aldehyde constitutes an efficient handle for further modification of the nanobodies. In vitro experiments confirmed the binding activity and selectivity of fluorescent conjugates toward the native antigen. Furthermore, the modification strategy allowed for production of a nanobody-drug conjugate that was active in vitro.

Complement receptor 3 (CR3, also known as Mac-1, integrin αMβ2, or CD11b/CD18) is expressed on a subset of myeloid and certain activated lymphoid cells. CR3 is essential for the phagocytosis of complement-opsonized particles such as pathogens and apoptotic or necrotic cells opsonized with the complement fragment iC3b and to a lesser extent C3dg. While the interaction between the iC3b thioester domain and the ligand binding CR3 αM I-domain is structurally and functionally well characterized, the nature of additional CR3-iC3b interactions required for phagocytosis of complement opsonized objects remain obscure. Here we analyzed the interaction between iC3b and the 150 kDa headpiece fragment of the CR3 ectodomain. Surface plasmon resonance experiments demonstrated a 30 nM affinity of CR3 for iC3b compared to 515 nM for the iC3b thioester domain. Small angle x-ray scattering analysis revealed that iC3b adopts an extended but preferred conformation in solution. Upon interaction with CR3, iC3b rearranges to form a compact receptor-ligand complex. Overall, the data suggest that the iC3b-CR3 interaction is of high affinity and relies on minor contacts formed between CR3 and regions outside the iC3b thioester domain. Our results rationalize the more efficient phagocytosis elicited by iC3b than by C3dg and pave the way for development of specific therapeutics for treatment of inflammatory and neurodegenerative diseases that do not interfere with recognition of non-complement CR3 ligands.

Smoke inhalation injury (SII) affects more than 50,000 people annually causing carbon monoxide (CO) poisoning. Although the increased blood level of carboxyhemoglobin (CO-Hb) is frequently used to confirm the diagnosis of SII, knowledge of its elimination in the acute phase is still limited. The aim of this study is to determine CO-Hb elimination rates and their differences in arterial (aCO-Hb) and mixed-venous (vCO-Hb) blood following severe SII in a clinically relevant ovine model. Forty-three chronically instrumented female sheep were subjected to SII (12 breaths, 4 sets) through tracheostomy tube under anesthesia and analgesia. After the SII, sheep were awakened and placed on a mechanical ventilator (FiO(2)=1.0, tidal volume 12 mL/kg, and PEEP=5cmH(2)O) and monitored. Arterial and mixed-venous blood samples were withdrawn simultaneously for blood gas analysis at various time points to determine CO-HB half-lifetime and an elimination curve. The mean of highest aCO-Hb level during SII was 70.8±13.9%. The aCO-Hb elimination curve showed an approximated exponential decay during the first 60 minutes. Per mixed linear regression model analysis, aCO-Hb significantly (p

AimMuscle contraction stimulates skeletal muscle glucose transport. Since it occurs independently of insulin, it is an important alternative pathway to increase glucose uptake in insulin-resistant states, but the intracellular signalling mechanisms are not fully understood. Muscle contraction activates group I p21-activated kinases (PAKs) in mouse and human skeletal muscle. PAK1 and PAK2 are downstream targets of Rac1, which is a key regulator of contraction-stimulated glucose transport. Thus, PAK1 and PAK2 could be downstream effectors of Rac1 in contraction-stimulated glucose transport. The current study aimed to test the hypothesis that PAK1 and/or PAK2 regulate contraction-induced glucose transport.MethodsGlucose transport was measured in isolated soleus and extensor digitorum longus (EDL) mouse skeletal muscle incubated either in the presence or absence of a pharmacological inhibitor (IPA-3) of group I PAKs or originating from whole-body PAK1 knockout (KO), muscle-specific PAK2 (m)KO or double whole-body PAK1 and muscle-specific PAK2 knockout mice.ResultsIPA-3 attenuated (−22%) the increase in muscle glucose transport in response to electrically-stimulated contraction. PAK1 was dispensable for contraction-stimulated glucose uptake in both soleus and EDL muscle. Lack of PAK2, either alone (−13%) or in combination with PAK1 (−14%), reduced contraction-stimulated glucose transport compared to control littermates in EDL, but not soleus muscle.ConclusionContraction-stimulated glucose transport in isolated glycolytic mouse EDL muscle is partly dependent on PAK2, but not PAK1.

Today’s world is characterized by increasing population density, human mobility, urbanization, and climate and ecological change. This global dynamic has various effects, including the increased appearance of emerging infectious diseases (EIDs), which pose a growing threat to global health security. Outbreaks of EIDs, like the 2013–2016 Ebola outbreak in West Africa or the current Ebola outbreak in Democratic Republic of the Congo (DRC), have not only put populations in low- and middle-income countries (LMIC) at risk in terms of morbidity and mortality, but they also have had a significant impact on economic growth in affected regions and beyond. The Coalition for Epidemic Preparedness Innovation (CEPI) is an innovative global partnership between public, private, philanthropic, and civil society organizations that was launched as the result of a consensus that a coordinated, international, and intergovernmental plan was needed to develop and deploy new vaccines to prevent future epidemics. CEPI is focusing on supporting candidate vaccines against the World Health Organization (WHO) Blueprint priority pathogens MERS-CoV, Nipah virus, Lassa fever virus, and Rift Valley fever virus, as well as Chikungunya virus, which is on the WHO watch list. The current vaccine portfolio contains a wide variety of technologies, ranging across recombinant viral vectors, nucleic acids, and recombinant proteins. To support and accelerate vaccine development, CEPI will also support science projects related to the development of biological standards and assays, animal models, epidemiological studies, and diagnostics, as well as build capacities for future clinical trials in risk-prone contexts.

Aim Muscle contraction stimulates skeletal muscle glucose transport. Since it occurs independently of insulin, it is an important alternative pathway to increase glucose transport in insulin‐resistant states, but the intracellular signaling mechanisms are not fully understood. Muscle contraction activates group I p21‐activated kinases (PAKs) in mouse and human skeletal muscle. PAK1 and PAK2 are downstream targets of Rac1, which is a key regulator of contraction‐stimulated glucose transport. Thus, PAK1 and PAK2 could be downstream effectors of Rac1 in contraction‐stimulated glucose transport. The current study aimed to test the hypothesis that PAK1 and/or PAK2 regulate contraction‐induced glucose transport. Methods Glucose transport was measured in isolated soleus and extensor digitorum longus (EDL) mouse skeletal muscle incubated either in the presence or absence of a pharmacological inhibitor (IPA‐3) of group I PAKs or originating from whole‐body PAK1 knockout, muscle‐specific PAK2 knockout or double whole‐body PAK1 and muscle‐specific PAK2 knockout mice. Results IPA‐3 attenuated (−22%) the increase in glucose transport in response to electrically stimulated contractions in soleus and EDL muscle. PAK1 was dispensable for contraction‐stimulated glucose transport in both soleus and EDL muscle. Lack of PAK2, either alone (−13%) or in combination with PAK1 (−14%), partly reduced contraction‐stimulated glucose transport compared to control littermates in EDL, but not soleus muscle. Conclusion Contraction‐stimulated glucose transport in isolated glycolytic mouse EDL muscle is partly dependent on PAK2, but not PAK1., In this study, we show that contraction‐stimulated glucose transport in isolated mouse skeletal muscle is unaffected by whole‐body knockout of PAK1. On the contrary, muscle‐specific knockout of PAK2 either alone or in combination with whole‐body PAK1 knockout partially reduces contraction‐stimulated glucose transport in glycolytic EDL muscle. These data suggest that contraction‐stimulated glucose transport in isolated glycolytic mouse EDL muscle is partly dependent on PAK2, but not PAK1.

Properdin stabilizes the alternative C3 convertase (C3bBb), whereas its role as pattern-recognition molecule mediating complement activation is disputed for decades. Previously, we have found that soluble collectin-12 (sCL-12) synergizes complement alternative pathway (AP) activation. However, whether this observation is C3 dependent is unknown. By application of the C3-inhibitor Cp40, we found that properdin in normal human serum bound to Aspergillus fumigatus solely in a C3b-dependent manner. Cp40 also prevented properdin binding when properdin-depleted serum reconstituted with purified properdin was applied, in analogy with the findings achieved by C3-depleted serum. However, when opsonized with sCL-12, properdin bound in a C3-independent manner exclusively via its tetrameric structure and directed in situ C3bBb assembly. In conclusion, a prerequisite for properdin binding and in situ C3bBb assembly was the initial docking of sCL-12. This implies a new important function of properdin in host defense bridging pattern recognition and specific AP activation. Copyright Zhang et al. This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.

HVDC technology has gone through major developments in the past decades, resulting in higher power ratings, increased efficiency, and the availability of effective means for HVDC grid protection. These developments have made overlay HVDC grids a viable option to accommodate the shift towards a carbon-free power system by enabling optimal use of renewable resources. In particular, overlay HVDC grids greatly increase the prospects of building (trans-)continental supergrids to facilitate global economic development. Notwithstanding the significant progress made over the last decades, overlay HVDC grids still encounter challenges due to the distance and amount of power involved. This paper focuses on analyzing the readiness of the current technologies and the challenges associated with overlay HVDC grids. An in-depth analysis is carried out to evaluate the applicability of current technologies for overlay HVDC grids. Based on the review of recent R&D efforts, the gaps and challenges towards the realization of a global HVDC grid are summarized. ispartof: CSEE Journal of Power and Energy Systems vol:7 issue:4 status: Published online

We describe a new approach for modelling airborne transient electromagnetic (TEM) data which combines the use of on- and off-time data for inversion. Specifically, the response is modelled using system response convolution both during and after transmitter ramp-down. High near-surface sensitivity can be achieved through a combination of fast transmitter ramp-down, broad receiver system bandwidth, efficient suppression or explanation of the primary field, and by combining the use of on-time gates with accurate knowledge of the system response. The system response can either be calculated based on the transfer function of the individual system components (i.e. receiver coil, amplifiers, low-pass filters and current waveform) or it can be measured at high altitude. The latter approach has the advantage of avoiding the specific modelling of individual system components. By comparing model parameter uncertainty when the on-time gates are included in the inversion versus when they are not, we show that a significant improvement in near-surface sensitivity is obtained. The method is used to invert both synthetic and field data. In the inversion of synthetic data, we see clear improvements in the determination of thin shallow layers, especially when they are resistive. This is confirmed by inversion of field data where we observe more pronounced structures with better definition of layer boundaries and layer resistivities.

This paper presents a low voltage, and large stroke Lorentz-force actuated continuous deformable polymer mirror for adaptive optics. A 5 × 5 actuator array clamped on the rigid mounting rail are formed from single crystal silicon flexible serpentine springs on either side of a rigid crossbar containing a narrow contact pillar. For the mirror, an epoxy-based SU-8 photoresist is used, which enables low voltage operation combined with Lorentz actuator. The Lorentz DM were tested and demonstrated a large 40 μm deformation at 9 mA actuation current, and needing