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Degueldre F, Aron S. Sperm competition increases sperm production and quality in Cataglyphis desert ants. Proc Biol Sci 2023; 290:20230216. [PMID: 36987648 PMCID: PMC10050944 DOI: 10.1098/rspb.2023.0216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 03/10/2023] [Indexed: 03/30/2023] Open
Abstract
Sperm competition is a pervasive evolutionary force that shapes sperm traits to maximize fertilization success. Indeed, it has been shown to increase sperm production in both vertebrates and invertebrates. However, sperm production is energetically costly, which may result in trade-offs among sperm traits. In eusocial hymenopterans, such as ants, mating dynamics impose unique selective pressures on ejaculate. Males are sperm limited: they enter adulthood with a fixed amount of sperm that will not be renewed. We explored whether sperm competition intensity was associated with sperm quantity and quality (i.e. sperm viability and DNA fragmentation) in nine Cataglyphis desert ants. Our results provide phylogenetically robust evidence that sperm competition is positively correlated with sperm production and sperm viability. However, it was unrelated to sperm DNA integrity, indicating the absence of a trade-off involving this trait. These findings underscore that sperm competition may strongly mould sperm traits and drive reproductive performance in eusocial Hymenoptera.
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Menashe-Oren A, Sánchez-Páez DA. Male Fertility and Internal Migration in Rural and Urban Sub-Saharan Africa. EUROPEAN JOURNAL OF POPULATION = REVUE EUROPEENNE DE DEMOGRAPHIE 2023; 39:10. [PMID: 36976350 PMCID: PMC10050504 DOI: 10.1007/s10680-023-09659-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 02/21/2023] [Indexed: 03/29/2023]
Abstract
Subnational differences in male fertility within sub-Saharan African countries have not been explored, nor the differences in male fertility according to migration status been sufficiently probed. We study divergences in rural and urban male fertility and investigate the relationship between male fertility and migration across 30 sub-Saharan African countries. We employ 67 Demographic and Health Surveys to estimate completed cohort fertility among men aged 50-64 according to migration status. Overall, we find that urban male fertility has declined faster than rural male fertility, widening the gap between the sectors. Rural-urban migrant men have lower fertility than their rural non-migrant counterparts. Men migrating within the rural sector have similarly high fertility as rural non-migrants, while urban-urban migrant men have even lower fertility than non-migrant urban men. Using country-fixed effects models, we find that among men with at least secondary education, differences in completed cohort fertility by migration status are widest. When we consider the timing of migration in relation to the timing of the birth of the last child, we observe that migrant men are a select group, having around two children less than non-migrant rural men. There is also evidence of adaptation to destination, though to a lesser extent. Furthermore, migration within the rural sector does not seem to be disruptive to fathering. These results indicate that rural-to-urban migration has the potential to delay rural fertility decline, and that urban male fertility is likely to decline further, especially as the proportion of urban-to-urban migration increases.
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178
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Duda E, Madayanad Suresh S, Hall D, Bagnich S, Saxena R, Cordes DB, Slawin AMZ, Beljonne D, Olivier Y, Köhler A, Zysman-Colman E. An Oligomer Approach for Blue Thermally Activated Delayed Fluorescent Emitters Based on Twisted Donor-Acceptor Units. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2023; 35:2027-2037. [PMID: 36936179 PMCID: PMC10018739 DOI: 10.1021/acs.chemmater.2c03438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 02/14/2023] [Indexed: 06/18/2023]
Abstract
The development of efficient blue donor-acceptor thermally activated delayed fluorescence (TADF) emitters remains a challenge. To enhance the efficiency of TADF-related processes of the emitter, we targeted a molecular design that would introduce a large number of intermediate triplet states between the lowest energy excited triplet (T1) and singlet (S1) excited states. Here, we introduce an oligomer approach using repetitive donor-acceptor units to gradually increase the number of quasi-degenerate states. In our design, benzonitrile (BN) moieties were selected as acceptors that are connected together via the amine donors, acting as bridges to adjacent BN acceptors. To preserve the photoluminescence emission wavelength across the series, we employed a design based on an ortho substitution pattern of the donors about the BN acceptor that induces a highly twisted conformation of the emitters, limiting the conjugation. Via a systematic photophysical study, we show that increasing the oligomer size allows for enhancement of the intersystem crossing and reverse intersystem crossing rates. We attribute the increasing intersystem crossing rate to the increasing number of intermediate triplet states along the series, confirmed by the time-dependent density functional theory. Overall, we report an approach to enhance the efficiency of TADF-related processes without changing the blue photoluminescence color.
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179
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Houeis L, Dolmans MM. Summary of the ISFP congress, Brussels, 10-12 November, 2022. J Assist Reprod Genet 2023; 40:433-442. [PMID: 36765026 PMCID: PMC10033808 DOI: 10.1007/s10815-023-02720-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 01/10/2023] [Indexed: 02/12/2023] Open
Abstract
The 7th International Congress of the ISFP was held in Brussels in November 2022. Hundreds of attendees from all over the world had the rare opportunity to hear the most distinguished leaders discuss and debate the latest advances in the field. Participants were also able to attend workshops under the guidance of skilled practitioners. Numerous topics were considered, including a recap on fertility preservation approaches in cancer and benign pathologies and a section on male factor infertility. Other aspects covered were in vitro maturation and poor responders, the impact of chemotherapy on the ovary, and future perspectives. Participants had the chance to listen to a symposium on fertility preservation techniques, and finally, a keynote lecture on fertility preservation in gynecological cancers brought this prominent and highly influential event to a close.
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Coomans de Brachène A, Scoubeau C, Musuaya AE, Costa-Junior JM, Castela A, Carpentier J, Faoro V, Klass M, Cnop M, Eizirik DL. Exercise as a non-pharmacological intervention to protect pancreatic beta cells in individuals with type 1 and type 2 diabetes. Diabetologia 2023; 66:450-460. [PMID: 36401627 PMCID: PMC9676790 DOI: 10.1007/s00125-022-05837-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 10/06/2022] [Indexed: 11/21/2022]
Abstract
AIMS/HYPOTHESIS Diabetes is characterised by progressive loss of functional pancreatic beta cells. None of the therapeutic agents used to treat diabetes arrest this process; preventing beta cell loss remains a major unmet need. We have previously shown that serum from eight young healthy male participants who exercised for 8 weeks protected human islets and insulin-producing EndoC-βH1 cells from apoptosis induced by proinflammatory cytokines or the endoplasmic reticulum (ER) stressor thapsigargin. Whether this protective effect is influenced by sex, age, training modality, ancestry or diabetes is unknown. METHODS We enrolled 82 individuals, male or female, non-diabetic or diabetic, from different origins, in different supervised training protocols for 8-12 weeks (including training at home during the COVID-19 pandemic). EndoC-βH1 cells were treated with 'exercised' serum or with the exerkine clusterin to ascertain cytoprotection from ER stress. RESULTS The exercise interventions were effective and improved [Formula: see text] values in both younger and older, non-obese and obese, non-diabetic and diabetic participants. Serum obtained after training conferred significant beta cell protection (28% to 35% protection after 4 and 8 weeks of training, respectively) from severe ER stress-induced apoptosis. Cytoprotection was not affected by the type of exercise training or participant age, sex, BMI or ancestry, and persisted for up to 2 months after the end of the training programme. Serum from exercised participants with type 1 or type 2 diabetes was similarly protective. Clusterin reproduced the beneficial effects of exercised sera. CONCLUSIONS/INTERPRETATION These data uncover the unexpected potential to preserve beta cell health by exercise training, opening a new avenue to prevent or slow diabetes progression through humoral muscle-beta cell crosstalk.
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181
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Reina A, Bose T, Srivastava V, Marshall JAR. Asynchrony rescues statistically optimal group decisions from information cascades through emergent leaders. ROYAL SOCIETY OPEN SCIENCE 2023; 10:230175. [PMID: 36938538 PMCID: PMC10014242 DOI: 10.1098/rsos.230175] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 02/21/2023] [Indexed: 06/18/2023]
Abstract
It is usually assumed that information cascades are most likely to occur when an early but incorrect opinion spreads through the group. Here, we analyse models of confidence-sharing in groups and reveal the opposite result: simple but plausible models of naive-Bayesian decision-making exhibit information cascades when group decisions are synchronous; however, when group decisions are asynchronous, the early decisions reached by Bayesian decision-makers tend to be correct and dominate the group consensus dynamics. Thus early decisions actually rescue the group from making errors, rather than contribute to it. We explore the likely realism of our assumed decision-making rule with reference to the evolution of mechanisms for aggregating social information, and known psychological and neuroscientific mechanisms.
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182
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Simpson J, Ray A, Marcon C, dos Santos Natividade R, Dorrazehi GM, Durlet K, Koehler M, Alsteens D. Single-Molecule Analysis of SARS-CoV-2 Binding to C-Type Lectin Receptors. NANO LETTERS 2023; 23:1496-1504. [PMID: 36758952 PMCID: PMC9924085 DOI: 10.1021/acs.nanolett.2c04931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/27/2023] [Indexed: 06/18/2023]
Abstract
Despite intense scrutiny throughout the pandemic, development of efficacious drugs against SARS-CoV-2 spread remains hindered. Understanding the underlying mechanisms of viral infection is fundamental for developing novel treatments. While angiotensin converting enzyme 2 (ACE2) is accepted as the key entry receptor of the virus, other infection mechanisms exist. Dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN) and its counterpart DC-SIGN-related (DC-SIGNR, also known as L-SIGN) have been recognized as possessing functional roles in COVID-19 disease and binding to SARS-CoV-2 has been demonstrated previously with ensemble and qualitative techniques. Here we examine the thermodynamic and kinetic parameters of the ligand-receptor interaction between these C-type lectins and the SARS-CoV-2 S1 protein using force-distance curve-based AFM and biolayer interferometry. We evidence that the S1 receptor binding domain is likely involved in this bond formation. Further, we employed deglycosidases and examined a nonglycosylated S1 variant to confirm the significance of glycosylation in this interaction. We demonstrate that the high affinity interactions observed occur through a mechanism distinct from that of ACE2.
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Chopin C, de Wergifosse S, Marchal N, Van Velthem P, Piraux L, Abreu Araujo F. Memristive and Tunneling Effects in 3D Interconnected Silver Nanowires. ACS OMEGA 2023; 8:6663-6668. [PMID: 36844586 PMCID: PMC9948158 DOI: 10.1021/acsomega.2c07171] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 01/20/2023] [Indexed: 06/18/2023]
Abstract
A network of silver nanowires (Ag-NWs) is grown by electrodeposition in a nanoporous membrane with interconnected nanopores. This bottom-up approach fabrication method gives a conducting network with a 3D architecture and a high density of Ag-NWs. The network is then functionalized during the etching process, which leads to a high initial resistance as well as memristive behavior. The latter is expected to arise from the creation and the destruction of conducting silver filaments in the functionalized Ag-NW network. Moreover, after several cycles of measurement, the resistance of the network switches from a high-resistance regime in the GΩ range with tunnel conduction to a low-resistance regime presenting negative differential resistance in the kΩ range.
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184
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Asher M, Bardini M, Catalano L, Jouclas R, Schweicher G, Liu J, Korobko R, Cohen A, Geerts Y, Beljonne D, Yaffe O. Mechanistic View on the Order-Disorder Phase Transition in Amphidynamic Crystals. J Phys Chem Lett 2023; 14:1570-1577. [PMID: 36748229 PMCID: PMC9940296 DOI: 10.1021/acs.jpclett.2c03316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 01/09/2023] [Indexed: 06/18/2023]
Abstract
We combine temperature-dependent low-frequency Raman measurements and first-principles calculations to obtain a mechanistic understanding of the order-disorder phase transition of 2,7-di-tert-butylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene (ditBu-BTBT) and 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-pentacene) semiconducting amphidynamic crystals. We identify the lattice normal modes associated with the phase transition by following the position and width of the Raman peaks with temperature and identifying peaks that exhibit nonlinear dependence toward the phase transition temperature. Our findings are interpreted according to the "hardcore mode" model previously used to describe order-disorder phase transitions in inorganic and hybrid crystals with a Brownian sublattice. Within the framework of this model, ditBu-BTBT exhibits an ideal behavior where only one lattice mode is associated with the phase transition. TIPS-pentacene deviates strongly from the model due to strong interactions between lattice modes. We discuss the origin of the different behaviors and suggest side-chain engineering as a tool to control polymorphism in amphidynamic crystals.
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185
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Dantis C, Rizzi EL, Baudin T. The Association between Religiosity and Fertility Intentions Via Grandparenting: Evidence from GGS Data. EUROPEAN JOURNAL OF POPULATION = REVUE EUROPEENNE DE DEMOGRAPHIE 2023; 39:1. [PMID: 36790655 PMCID: PMC9931957 DOI: 10.1007/s10680-023-09652-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 10/16/2022] [Indexed: 02/16/2023]
Abstract
Although the literature concerning the association between religiosity and fertility in European countries is already quite extensive, studies exploring the mechanisms of action of religiosity are rare. The main aim of this article is to investigate whether grandparental childcare is a mediating or moderating variable in the association between attendance at religious services and the intention to have a second or third child. Building on previous literature, we assume that parents who are more religious might put more effort into establishing a positive relation with the grandparents of their child/children. Consequently, compared to parents who are less religious, those who are more religious could be more receptive to possible encouragement from grandparents to have another child and may be more optimistic regarding grandparents' involvement with an additional child. Using Generations and Gender Survey (GGS) data for eleven European countries, we find evidence of a strong and positive effect of attendance at religious services on fertility intentions. Receipt of regular or weekly help from grandparents positively moderates the association between attendance at religious services and fertility intentions, albeit only for male respondents and mainly for the intention to have a second child.
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186
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Bettoni R, Hudson C, Williaume G, Sirour C, Yasuo H, de Buyl S, Dupont G. Model of neural induction in the ascidian embryo. PLoS Comput Biol 2023; 19:e1010335. [PMID: 36735746 PMCID: PMC9931142 DOI: 10.1371/journal.pcbi.1010335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 02/15/2023] [Accepted: 01/17/2023] [Indexed: 02/04/2023] Open
Abstract
How cell specification can be controlled in a reproducible manner is a fundamental question in developmental biology. In ascidians, a group of invertebrate chordates, geometry plays a key role in achieving this control. Here, we use mathematical modeling to demonstrate that geometry dictates the neural-epidermal cell fate choice in the 32-cell stage ascidian embryo by a two-step process involving first the modulation of ERK signaling and second, the expression of the neural marker gene, Otx. The model describes signal transduction by the ERK pathway that is stimulated by FGF and attenuated by ephrin, and ERK-mediated control of Otx gene expression, which involves both an activator and a repressor of ETS-family transcription factors. Considering the measured area of cell surface contacts with FGF- or ephrin-expressing cells as inputs, the solutions of the model reproduce the experimental observations about ERK activation and Otx expression in the different cells under normal and perturbed conditions. Sensitivity analyses and computations of Hill coefficients allow us to quantify the robustness of the specification mechanism controlled by cell surface area and to identify the respective role played by each signaling input. Simulations also predict in which conditions the dual control of gene expression by an activator and a repressor that are both under the control of ERK can induce a robust ON/OFF control of neural fate induction.
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187
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August A, Marichal T. Eosinophils and Lung Mucosal Antibody Production: Is Location the Key? Am J Respir Cell Mol Biol 2023; 68:124-126. [PMID: 36306503 PMCID: PMC9986563 DOI: 10.1165/rcmb.2022-0410ed] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
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188
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Biliak K, Nikitin D, Ali-Ogly S, Protsak M, Pleskunov P, Tosca M, Sergievskaya A, Cornil D, Cornil J, Konstantinidis S, Košutová T, Černochová Z, Štěpánek P, Hanuš J, Kousal J, Hanyková L, Krakovský I, Choukourov A. Plasmonic Ag/Cu/PEG nanofluids prepared when solids meet liquids in the gas phase. NANOSCALE ADVANCES 2023; 5:955-969. [PMID: 36756512 PMCID: PMC9891094 DOI: 10.1039/d2na00785a] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 12/22/2022] [Indexed: 06/18/2023]
Abstract
Since the time of Faraday's experiments, the optical response of plasmonic nanofluids has been tailored by the shape, size, concentration, and material of nanoparticles (NPs), or by mixing different types of NPs. To date, water-based liquids have been the most extensively investigated host media, while polymers, such as poly(ethylene glycol) (PEG), have frequently been added to introduce repulsive steric interactions and protect NPs from agglomeration. Here, we introduce an inverse system of non-aqueous nanofluids, in which Ag and Cu NPs are dispersed in PEG (400 g mol-1), with no solvents or chemicals involved. Our single-step approach comprises the synthesis of metal NPs in the gas phase using sputtering-based gas aggregation cluster sources, gas flow transport of NPs, and their deposition (optionally simultaneous) on the PEG surface. Using computational fluid dynamics simulations, we show that NPs diffuse into PEG at an average velocity of the diffusion front of the order of μm s-1, which is sufficient for efficient loading of the entire polymer bulk. We synthesize yellow Ag/PEG, green Cu/PEG, and blue Ag/Cu/PEG nanofluids, in which the color is given by the position of the plasmon resonance. NPs are prone to partial agglomeration and sedimentation, with a slower kinetics for Cu. Density functional theory calculations combined with UV-vis data and zeta-potential measurements prove that the surface oxidation to Cu2O and stronger electrostatic repulsion are responsible for the higher stability of Cu NPs. Adopting the De Gennes formalism, we estimate that PEG molecules adsorb on the NP surface in mushroom coordination, with the thickness of the adsorbed layer L < 1.4 nm, grafting density σ < 0.20, and the average distance between the grafted chains D > 0.8 nm. Such values provide sufficient steric barriers to retard, but not completely prevent, agglomeration. Overall, our approach offers an excellent platform for fundamental research on non-aqueous nanofluids, with metal-polymer and metal-metal interactions unperturbed by the presence of solvents or chemical residues.
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Ainelo A, Caballero-Montes J, Bulvas O, Ernits K, Coppieters ‘t Wallant K, Takada H, Craig SZ, Mazzucchelli G, Zedek S, Pichová I, Atkinson GC, Talavera A, Martens C, Hauryliuk V, Garcia-Pino A. The structure of DarB in complex with Rel NTD reveals nonribosomal activation of Rel stringent factors. SCIENCE ADVANCES 2023; 9:eade4077. [PMID: 36652515 PMCID: PMC9848473 DOI: 10.1126/sciadv.ade4077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 12/20/2022] [Indexed: 06/17/2023]
Abstract
Rel stringent factors are bifunctional ribosome-associated enzymes that catalyze both synthesis and hydrolysis of the alarmones (p)ppGpp. Besides the allosteric control by starved ribosomes and (p)ppGpp, Rel is regulated by various protein factors depending on specific stress conditions, including the c-di-AMP-binding protein DarB. However, how these effector proteins control Rel remains unknown. We have determined the crystal structure of the DarB2:RelNTD2 complex, uncovering that DarB directly engages the SYNTH domain of Rel to stimulate (p)ppGpp synthesis. This association with DarB promotes a SYNTH-primed conformation of the N-terminal domain region, markedly increasing the affinity of Rel for ATP while switching off the hydrolase activity of the enzyme. Binding to c-di-AMP rigidifies DarB, imposing an entropic penalty that precludes DarB-mediated control of Rel during normal growth. Our experiments provide the basis for understanding a previously unknown mechanism of allosteric regulation of Rel stringent factors independent of amino acid starvation.
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190
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Waeytens J, De Meutter J, Goormaghtigh E, Dazzi A, Raussens V. Determination of Secondary Structure of Proteins by Nanoinfrared Spectroscopy. Anal Chem 2023; 95:621-627. [PMID: 36598929 PMCID: PMC9851152 DOI: 10.1021/acs.analchem.2c01431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 10/21/2022] [Indexed: 01/05/2023]
Abstract
Nanoscale infrared spectroscopy (AFMIR) is becoming an important tool for the analysis of biological sample, in particular protein assemblies, at the nanoscale level. While the amide I band is usually used to determine the secondary structure of proteins in Fourier transform infrared spectroscopy, no tool has been developed so far for AFMIR. The paper introduces a method for the study of secondary structure of protein based on a protein library of 38 well-characterized proteins. Ascending stepwise linear regression (ASLR) and partial least square (PLS) regression were used to correlate spectrum characteristic bands with the major secondary structures (α-helixes and β-sheets). ASLR appears to provide better results than PLS. The secondary structure predictions are characterized by a root mean square standard error in a cross validation of 6.39% for α-helixes and 6.23% for β-sheets.
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191
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Chauvin A, Puglisi W, Thiry D, Satriano C, Snyders R, Bittencourt C. Combining physical vapor deposition structuration with dealloying for the creation of a highly efficient SERS platform. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2023; 14:83-94. [PMID: 36761681 PMCID: PMC9843236 DOI: 10.3762/bjnano.14.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 12/20/2022] [Indexed: 06/18/2023]
Abstract
Nanostructured noble metal thin films are highly studied for their interesting plasmonic properties. The latter can be effectively used for the detection of small and highly diluted molecules by the surface-enhanced Raman scattering (SERS) effect. Regardless of impressive detection limits achieved, synthesis complexity and the high cost of gold restrict its use in devices. Here, we report on a novel two-step approach that combines the deposition of a silver-aluminum thin film with dealloying to design and fabricate efficient SERS platforms. The magnetron sputtering technique was used for the deposition of the alloy thin film to be dealloyed. After dealloying, the resulting silver nanoporous structures revealed two degrees of porosity: macroporosity, associated to the initial alloy morphology, and nanoporosity, related to the dealloying step. The resulting nanoporous columnar structure was finely optimized by tuning deposition (i.e., the alloy chemical composition) and dealloying (i.e., dealloying media) parameters to reach the best SERS properties. These are reported for samples dealloyed in HCl and with 30 atom % of silver at the initial state with a detection limit down to 10-10 mol·L-1 for a solution of rhodamine B.
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192
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van de Velde SJ, Dale AW, Arndt S. Bioturbation and the δ 56Fe signature of dissolved iron fluxes from marine sediments. ROYAL SOCIETY OPEN SCIENCE 2023; 10:220010. [PMID: 36704258 PMCID: PMC9874279 DOI: 10.1098/rsos.220010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 01/05/2023] [Indexed: 06/18/2023]
Abstract
We developed a reaction-transport model capable of tracing iron isotopes in marine sediments to quantify the influence of bioturbation on the isotopic signature of the benthic dissolved (DFe) flux. By fitting the model to published data from marine sediments, we calibrated effective overall fractionation factors for iron reduction (-1.3‰), oxidation (+0.4‰), iron-sulfide precipitation (+0.5‰) and dissolution (-0.5‰) and pyrite precipitation (-0.7‰) that agree with literature values. Results show that for bottom-water oxygen concentrations greater than 50 µM, higher bioturbation increased the benthic DFe flux and its δ 56Fe signature. By contrast, for oxygen concentrations less than 50 µM, higher bioturbation decreased the benthic DFe flux and its δ 56Fe signature. The expressed overall fractionation of the benthic DFe flux relative to the δ 56Fe of the iron oxides entering the sediment ranges from -1.67‰ to 0.0‰. On a global scale, the presence of bioturbation increases sedimentary DFe release from approximately 70 G mol DFe yr-1 to approximately 160 G mol DFe yr-1 and decreases the δ 56Fe signature of the DFe flux.
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Balcaen T, Piens C, Mwema A, Chourrout M, Vandebroek L, Des Rieux A, Chauveau F, De Borggraeve WM, Hoffmann D, Kerckhofs G. Revealing the three-dimensional murine brain microstructure by contrast-enhanced computed tomography. Front Neurosci 2023; 17:1141615. [PMID: 37034159 PMCID: PMC10076597 DOI: 10.3389/fnins.2023.1141615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 03/08/2023] [Indexed: 04/11/2023] Open
Abstract
To improve our understanding of the brain microstructure, high-resolution 3D imaging is used to complement classical 2D histological assessment techniques. X-ray computed tomography allows high-resolution 3D imaging, but requires methods for enhancing contrast of soft tissues. Applying contrast-enhancing staining agents (CESAs) ameliorates the X-ray attenuating properties of soft tissue constituents and is referred to as contrast-enhanced computed tomography (CECT). Despite the large number of chemical compounds that have successfully been applied as CESAs for imaging brain, they are often toxic for the researcher, destructive for the tissue and without proper characterization of affinity mechanisms. We evaluated two sets of chemically related CESAs (organic, iodinated: Hexabrix and CA4+ and inorganic polyoxometalates: 1:2 hafnium-substituted Wells-Dawson phosphotungstate and Preyssler anion), for CECT imaging of healthy murine hemispheres. We then selected the CESA (Hexabrix) that provided the highest contrast between gray and white matter and applied it to a cuprizone-induced demyelination model. Differences in the penetration rate, effect on tissue integrity and affinity for tissue constituents have been observed for the evaluated CESAs. Cuprizone-induced demyelination could be visualized and quantified after Hexabrix staining. Four new non-toxic and non-destructive CESAs to the field of brain CECT imaging were introduced. The added value of CECT was shown by successfully applying it to a cuprizone-induced demyelination model. This research will prove to be crucial for further development of CESAs for ex vivo brain CECT and 3D histopathology.
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Boutsen L, Costenoble E, Pollé O, Erdem K, Bugli C, Lysy PA. Influence of the occurrence and duration of partial remission on short-term metabolic control in type 1 diabetes: the DIABHONEY pediatric study. Ther Adv Endocrinol Metab 2023; 14:20420188221145550. [PMID: 36699944 PMCID: PMC9869204 DOI: 10.1177/20420188221145550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 11/26/2022] [Indexed: 01/22/2023] Open
Abstract
OBJECTIVE To evaluate the residual effect of partial remission (PR) on immediate post-PR glycemic control according to its occurrence and duration in a cohort of children with type 1 diabetes mellitus (T1DM). PATIENTS AND METHODS Values of glycemic control parameters [i.e. HbA1C, insulin dose-adjusted hemoglobin A1C (IDAA1C), glycemic target-adjusted HbA1C (GTAA1C)] and data from glucose monitoring devices from 189 pediatric patients with new-onset type 1 diabetes were collected retrospectively from 24 months. Patients were characterized according to their remission status (PR+ and PR-). PR+ patients were subdivided into three subgroups regarding PR duration [i.e. short (⩾3-⩽6 months), intermediate (>6-⩽12 months), and long PR (>12-⩽14 months)]. We compared glycemic control data from each PR+ subgroup at +6 and +12 months post-PR with PR- patients at the same postdiagnosis time. Second, PR+ subgroups were compared with each other. RESULTS PR+ patients showed improved glycemic control (i.e. HbA1C, IDAA1C, and GTAA1C) at + 6 months post-PR when compared with nonremitters (PR-), independently of the PR duration subgroups (p < 0.05). Interestingly, patients in long PR+ subgroup exhibited higher positive residual effect than short PR+ subgroup with lower GTAA1C scores (p = 0.02), better time in range (TIR) (p = 0.003), less time in hypoglycemia (10.45 versus 16.13%, p = 0.03) and less glycemic variability (83.1 mg/dl versus 98.84 mg/dl, p = 0.03). No significant differences were found for glucose control between PR+ and PR- patients at +12 months post-PR. CONCLUSION This study supports the positive impact of PR occurrence and duration on short-term metabolic control (better HbA1C levels, IDAA1C and GTAA1C scores, TIR, and less glycemic variability) with the residual effect increasing according to PR duration.
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Lee JR, Terauds A, Carwardine J, Shaw JD, Fuller RA, Possingham HP, Chown SL, Convey P, Gilbert N, Hughes KA, McIvor E, Robinson SA, Ropert-Coudert Y, Bergstrom DM, Biersma EM, Christian C, Cowan DA, Frenot Y, Jenouvrier S, Kelley L, Lee MJ, Lynch HJ, Njåstad B, Quesada A, Roura RM, Shaw EA, Stanwell-Smith D, Tsujimoto M, Wall DH, Wilmotte A, Chadès I. Threat management priorities for conserving Antarctic biodiversity. PLoS Biol 2022; 20:e3001921. [PMID: 36548240 PMCID: PMC9778584 DOI: 10.1371/journal.pbio.3001921] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 11/16/2022] [Indexed: 12/24/2022] Open
Abstract
Antarctic terrestrial biodiversity faces multiple threats, from invasive species to climate change. Yet no large-scale assessments of threat management strategies exist. Applying a structured participatory approach, we demonstrate that existing conservation efforts are insufficient in a changing world, estimating that 65% (at best 37%, at worst 97%) of native terrestrial taxa and land-associated seabirds are likely to decline by 2100 under current trajectories. Emperor penguins are identified as the most vulnerable taxon, followed by other seabirds and dry soil nematodes. We find that implementing 10 key threat management strategies in parallel, at an estimated present-day equivalent annual cost of US$23 million, could benefit up to 84% of Antarctic taxa. Climate change is identified as the most pervasive threat to Antarctic biodiversity and influencing global policy to effectively limit climate change is the most beneficial conservation strategy. However, minimising impacts of human activities and improved planning and management of new infrastructure projects are cost-effective and will help to minimise regional threats. Simultaneous global and regional efforts are critical to secure Antarctic biodiversity for future generations.
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Alagh A, Annanouch FE, Sierra-Castillo A, Haye E, Colomer JF, Llobet E. Three-Dimensional Assemblies of Edge-Enriched WSe 2 Nanoflowers for Selectively Detecting Ammonia or Nitrogen Dioxide. ACS APPLIED MATERIALS & INTERFACES 2022; 14:54946-54960. [PMID: 36469520 PMCID: PMC9756288 DOI: 10.1021/acsami.2c16299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
Herein, we present, for the first time, a chemoresistive-type gas sensor composed of two-dimensional WSe2, fabricated by a simple selenization of tungsten trioxide (WO3) nanowires at atmospheric pressure. The morphological, structural, and chemical composition investigation shows the growth of vertically oriented three-dimensional (3D) assemblies of edge-enriched WSe2 nanoplatelets arrayed in a nanoflower shape. The gas sensing properties of flowered nanoplatelets (2H-WSe2) are investigated thoroughly toward specific gases (NH3 and NO2) at different operating temperatures. The integration of 3D WSe2 with unique structural arrangements resulted in exceptional gas sensing characteristics with dual selectivity toward NH3 and NO2 gases. Selectivity can be tuned by selecting its operating temperature (150 °C for NH3 and 100 °C for NO2). For instance, the sensor has shown stable and reproducible responses (24.5%) toward 40 ppm NH3 vapor detection with an experimental LoD < 2 ppm at moderate temperatures. The gas detecting capabilities for CO, H2, C6H6, and NO2 were also investigated to better comprehend the selectivity of the nanoflower sensor. Sensors showed repeatable responses with high sensitivity to NO2 molecules at a substantially lower operating temperature (100 °C) (even at room temperature) and LoD < 0.1 ppm. However, the gas sensing properties reveal high selectivity toward NH3 gas at moderate operating temperatures. Moreover, the sensor demonstrated high resilience against ambient humidity (Rh = 50%), demonstrating its remarkable stability toward NH3 gas detection. Considering the detection of NO2 in a humid ambient atmosphere, there was a modest increase in the sensor response (5.5%). Furthermore, four-month long-term stability assessments were also taken toward NH3 gas detection, and sensors showed excellent response stability. Therefore, this study highlights the practical application of the 2H variant of WSe2 nanoflower gas sensors for NH3 vapor detection.
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Dosso J, Oubaha H, Fasano F, Melinte S, Gohy JF, Hughes CE, Harris KDM, Demitri N, Abrami M, Grassi M, Bonifazi D. Boron Nitride-Doped Polyphenylenic Organogels. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2022; 34:10670-10680. [PMID: 36530943 PMCID: PMC9753561 DOI: 10.1021/acs.chemmater.2c01766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 11/03/2022] [Indexed: 06/17/2023]
Abstract
Herein, we describe the synthesis of the first boron nitride-doped polyphenylenic material obtained through a [4 + 2] cycloaddition reaction between a triethynyl borazine unit and a biscyclopentadienone derivative, which undergoes organogel formation in chlorinated solvents (the critical jellification concentration is 4% w/w in CHCl3). The polymer has been characterized extensively by Fourier-transform infrared spectroscopy, solid-state 13C NMR, solid-state 11B NMR, and by comparison with the isolated monomeric unit. Furthermore, the polymer gels formed in chlorinated solvents have been thoroughly characterized and studied, showing rheological properties comparable to those of polyacrylamide gels with a low crosslinker percentage. Given the thermal and chemical stability, the material was studied as a potential support for solid-state electrolytes. showing properties comparable to those of polyethylene glycol-based electrolytes, thus presenting great potential for the application of this new class of material in lithium-ion batteries.
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Lizcano-Perret B, Lardinois C, Wavreil F, Hauchamps P, Herinckx G, Sorgeloos F, Vertommen D, Gatto L, Michiels T. Cardiovirus leader proteins retarget RSK kinases toward alternative substrates to perturb nucleocytoplasmic traffic. PLoS Pathog 2022; 18:e1011042. [PMID: 36508477 PMCID: PMC9779665 DOI: 10.1371/journal.ppat.1011042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 12/22/2022] [Accepted: 12/01/2022] [Indexed: 12/14/2022] Open
Abstract
Proteins from some unrelated pathogens, including small RNA viruses of the family Picornaviridae, large DNA viruses such as Kaposi sarcoma-associated herpesvirus and even bacteria of the genus Yersinia can recruit cellular p90-ribosomal protein S6 kinases (RSKs) through a common linear motif and maintain the kinases in an active state. On the one hand, pathogens' proteins might hijack RSKs to promote their own phosphorylation (direct target model). On the other hand, some data suggested that pathogens' proteins might dock the hijacked RSKs toward a third interacting partner, thus redirecting the kinase toward a specific substrate. We explored the second hypothesis using the Cardiovirus leader protein (L) as a paradigm. The L protein is known to trigger nucleocytoplasmic trafficking perturbation, which correlates with hyperphosphorylation of phenylalanine-glycine (FG)-nucleoporins (FG-NUPs) such as NUP98. Using a biotin ligase fused to either RSK or L, we identified FG-NUPs as primary partners of the L-RSK complex in infected cells. An L protein mutated in the central RSK-interaction motif was readily targeted to the nuclear envelope whereas an L protein mutated in the C-terminal domain still interacted with RSK but failed to interact with the nuclear envelope. Thus, L uses distinct motifs to recruit RSK and to dock the L-RSK complex toward the FG-NUPs. Using an analog-sensitive RSK2 mutant kinase, we show that, in infected cells, L can trigger RSK to use NUP98 and NUP214 as direct substrates. Our data therefore illustrate a novel virulence mechanism where pathogens' proteins hijack and retarget cellular protein kinases toward specific substrates, to promote their replication or to escape immunity.
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Gomez-Lopez A, Grignard B, Calvo I, Detrembleur C, Sardon H. Accelerating the Curing of Hybrid Poly(Hydroxy Urethane)-Epoxy Adhesives by the Thiol-Epoxy Chemistry. ACS APPLIED POLYMER MATERIALS 2022; 4:8786-8794. [PMID: 36532887 PMCID: PMC9745729 DOI: 10.1021/acsapm.2c01195] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Accepted: 09/30/2022] [Indexed: 06/17/2023]
Abstract
The polyaddition between dicyclic carbonates and diamines leading to poly(hydroxy urethane)s (PHUs) has emerged as the preferred method for the synthesis of green, non-isocyanate polyurethanes. However, when proposed for use as structural adhesives, the long times for completion of aminolysis of the 5-membered cyclic carbonates under ambient conditions force the use of complementary chemistries to accelerate the curing process. In this work, a system that combines an amino-terminated PHU (NH2-PHU-NH2), an epoxy resin, and a thiol compound was employed to develop high-shear strength PHU-epoxy hybrid adhesives able to cure at room temperature in short times. A NH2-PHU-NH2 prepolymer synthesized by using a sub-stoichiometric quantity of dicyclic carbonates was mixed with a bisphenol A-based epoxy resin for the preparation of the structural adhesive. While this adhesive showed good lap-shear strength and shear resistance under static load and temperature, the curing process was slow. In order to speed up the curing process, a thiol (trimethylolpropane tris(3-mercapto propionate)) was added and its impact on the curing process as well as on the adhesive properties was evaluated. The trifunctional thiol additive allowed for faster curing in the presence of the 1,1,3,3-tetramethylguanidine basic catalyst. Moreover, a combination of NH2-PHU-NH2 and the thiol as curing agents for the epoxy resin resulted in adhesives with superior toughness, without any deterioration of the ultimate lap-shear strength or shear resistance under load and temperature, making these adhesives suitable for high-demand applications in the automotive industry.
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Quintero-Yanes A, Mayard A, Hallez R. The two-component system ChvGI maintains cell envelope homeostasis in Caulobacter crescentus. PLoS Genet 2022; 18:e1010465. [PMID: 36480504 PMCID: PMC9731502 DOI: 10.1371/journal.pgen.1010465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 10/09/2022] [Indexed: 12/13/2022] Open
Abstract
Two-component systems (TCS) are often used by bacteria to rapidly assess and respond to environmental changes. The ChvG/ChvI (ChvGI) TCS conserved in α-proteobacteria is known for regulating expression of genes related to exopolysaccharide production, virulence and growth. The sensor kinase ChvG autophosphorylates upon yet unknown signals and phosphorylates the response regulator ChvI to regulate transcription. Recent studies in Caulobacter crescentus showed that chv mutants are sensitive to vancomycin treatment and fail to grow in synthetic minimal media. In this work, we identified the osmotic imbalance as the main cause of growth impairment in synthetic minimal media. We also determined the ChvI regulon and found that ChvI regulates cell envelope architecture by controlling outer membrane, peptidoglycan assembly/recycling and inner membrane proteins. In addition, we found that ChvI phosphorylation is also activated upon antibiotic treatment with vancomycin. We also challenged chv mutants with other cell envelope related stress and found that treatment with antibiotics targeting transpeptidation of peptidoglycan during cell elongation impairs growth of the mutant. Finally, we observed that the sensor kinase ChvG relocates from a patchy-spotty distribution to distinctive foci after transition from complex to synthetic minimal media. Interestingly, this pattern of (re)location has been described for proteins involved in cell growth control and peptidoglycan synthesis upon osmotic shock. Overall, our data support that the ChvGI TCS is mainly used to monitor and respond to osmotic imbalances and damages in the peptidoglycan layer to maintain cell envelope homeostasis.
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