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A hallmark of animals is the coordination of whole-body movement. Neurons and muscles are central to this, yet coordinated movements also exist in sponges that lack these cell types. Sponges are sessile animals with a complex canal system for filter-feeding. They undergo whole-body movements resembling "contractions" that lead to canal closure and water expulsion. Here, we combine live 3D optical coherence microscopy, pharmacology, and functional proteomics to elucidate the sequence and detail of shape changes, the tissues and molecular physiology involved, and the control of these movements. Morphometric analysis and targeted perturbation suggest that the movement is driven by the relaxation of actomyosin stress fibers in epithelial canal cells, which leads to whole-body deflation via collapse of the incurrent and expansion of the excurrent canal system. Thermal proteome profiling and quantitative phosphoproteomics confirm the control of cellular relaxation by an Akt/NO/PKG/PKA pathway. Agitation-induced deflation leads to differential phosphorylation of proteins forming epithelial cell junctions, implying their mechanosensitive role. Unexpectedly, untargeted metabolomics detect a concomitant decrease in antioxidant molecules during deflation, reflecting an increase in reactive oxygen species. Together with the secretion of proteinases, cytokines, and granulin, this indicates an inflammation-like state of the deflating sponge reminiscent of vascular endothelial cells experiencing oscillatory shear stress. These results suggest the conservation of an ancient relaxant-inflammatory response of perturbed fluid-carrying systems in animals and offer a possible mechanism for whole-body coordination through diffusible paracrine signals and mechanotransduction., Competing Interests: Declaration of interests M.N. is the founder of bionic consulting Dr. Michael Nickel., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The aim of this paper is to show how the analytical modelling of a simplified acoustic device (herein a simplified wind musical instrument) may be a relevant educational way to study several aspects of the behavior of an idealized component [herein a one-dimensional (1-D) resonator], which is the core component of the device considered. A time-dependent source, whether sinusoidal, impulse, or representing approximate valve-effects of the reed, is coupled to the resonator in the analytical modelling. The unavoidable thermo-viscous parietal dissipation, as well as an approximate radiation effect, are accounted for. After a brief presentation of the problem, precisely posed and solved in detail analytically in an approximate manner, results in both the frequency domain and in the time domain are presented. These results include the properties of the transient behaviors (both the starting transient and the transient decay), illustrating the main features of the resonator., (© 2023 Acoustical Society of America.)

Neisseria meningitidis (Nm) is asymptomatically carried in the nasopharynx of 5-10% adults, although certain populations, such as men who have sex with men (MSM), exhibit a higher colonisation rate. Interest in Nm carriage has been renewed, owed to meningitis outbreaks within populations of MSM. The aim of this study was to characterise Nm isolates and risk factors for its carriage among MSM attending a sexual health unit. A retrospective cross-sectional study was undertaken between June 2018 and December 2021. We took anal, oropharyngeal, urethral, and blood samples as part of the sexually transmitted infection screening procedures routinely implemented. Nm isolates were subjected to antimicrobial susceptibility testing; the serogroup and genogroup were determined by multi-locus sequence typing. A total of 399 subjects were recruited, and the Nm oropharyngeal carriage rate was 29%, similar among both people living with HIV (PLWH) and uninfected individuals. Nm carriage was less common in vaccinated individuals, especially those who had received the tetravalent vaccine (2.6% vs. 10.6%, p = 0.008). The most frequent serogroups were B (40%) and non-groupable (45%). Most of the isolates were susceptible to ciprofloxacin (96%) and ceftriaxone (100%). However, we identified 21 strains (20%) belonging to hyperinvasive lineages (CC11, CC4821, CC32, CC41/44, CC213, and CC269), most of which belonged to serogroup B. Given that vaccination with MenACWY was associated with a low Nm carriage, we encourage routine vaccination of all MSM. Moreover, the administration of the meningitis B vaccine should also be assessed considering that several invasive lines included in serogroup B are circulating among MSM., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Diatoms play a key role in the marine silica cycle, but recent studies have shown that sponges can also have an important effect on this dynamic. They accumulate large stocks of biogenic silica within their bodies over long periods, which are thought to vary little on an intra-annual scale. The observation of an abrupt decline in sponge biomass in parallel with large increases in abundance of a spongivorous nudibranch (Doris verrucosa) led us to conduct a year-long study on the effect of nudibranch predation on the silicon budget of a sponge (Hymeniacidon perlevis) population. After 5 months of predation, the abundance of sponge individuals did not change but their biomass decreased by 95%, of which 48% was explained by nudibranch predation. About 97% of sponge spicules ingested by nudibranchs while feeding was excreted, most of them unbroken, implying a high rate of sponge silica deposition in the surrounding sediments. After predation, sponges partially recovered their biomass stocks within 7 months. This involved a rapid growth rate and large assimilation of dissolved silicon. Surprisingly, the highest rates of silicon absorption occurred when dissolved silicon concentration in seawater was minimal (< 1.5 µM). These findings suggest that the annual sponge predation-recovery cycle triggers unprecedented intra-annual changes in sponge silicon stocks and boosts the cycling of this nutrient. They also highlight the need for intra-annual data collection to understand the dynamics and resilience of sponge ecosystem functioning., (© 2023. The Author(s).)

Introduction: Pre-exposure prophylaxis (PrEP) has become a useful tool to reduce the transmission of human immunodeficiency virus (HIV) in key populations. In this article we assessed the effectiveness, safety, adherence, sexually transmitted infections (STIs) dynamics, and frequency of anal dysplasia among a real-life cohort of PrEP users in Northwest Spain., Methods: A retrospective cohort study was undertaken in the Alvaro-Cunqueiro Hospital, Vigo which included every individual who started daily emtricitabine/tenofovir-disoproxil-fumarate (FTC/TDF) between November-2019 and October-2021. Clinical and epidemiological data were obtained from the patient's medical records. The effectiveness and safety of FTC/TDF were assessed by HIV serology and renal function monitoring every 3 months. Anal, urethral, and oropharyngeal exudates were collected quarterly after the baseline visit., Results: A total of 126 individuals were considered eligible, most of the participants had previously been diagnosed with a STI (60.3%), 22% had consumed recreational drugs in the year prior, and 13% had engaged in chemsex. At the end of the follow-up, no cases of HIV infection were detected; 3 patients had discontinued FTC/TDF because of side effects but none of them had presented renal toxicity. In addition, the diagnosis of STIs during the follow-up was common (100 cases in 54 patients). Moreover, engagement in chemsex was more common within this latter group (22 vs. 6%, p = 0.013). Among the study population included in the anal screening programme, the frequency of dysplasia was 9%., Conclusions: FTC/TDF was effective, safe, and tolerable in a real-life cohort; adherence remained high throughout the study period (79%). However, a high number of STIs were diagnosed, especially among patients who engaged in chemsex., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Pérez-González, Represa, Coll, Potel, Rodríguez-Rivero, Flores, Vázquez-Estévez, Ocampo, Pousada and Poveda.)

Implant-associated infection due to biofilm formation is a growing problem. Given that silver nanoparticles (Ag-NPs) have shown antibacterial effects, our goal is to study their effect against multispecies biofilm involved in the development of peri-implantitis. To this purpose, Ag-NPs were synthesized by laser ablation in de-ionized water using two different lasers, leading to the production of colloidal suspensions. Subsequently, part of each suspension was subjected to irradiation one and three times with the same laser source with which it was obtained. Ag-NPs were immobilized on the surface of titanium discs and the resultant materials were compared with unmodified titanium coupons. Nanoparticles were physico-chemically analysed to determine their shape, crystallinity, chemical composition, and mean diameter. The materials were incubated for 90 min or 48 h, to evaluate bacterial adhesion or biofilm formation respectively with Staphylococcus aureus or oral mixed bacterial flora composed of Streptococcus oralis , Actinomyces naeslundii , Veionella dispar , and Porphyromonas gingivalis . Ag-NPs help prevent the formation of biofilms both by S. aureus and by mixed oral bacterial flora. Nanoparticles re-irradiated three times showed the biggest antimicrobial effects. Modifying dental implants in this way could prevent the development of peri-implantitis.

Lactic acid bacteria (LAB) of the genus Lactiplantibacillus have been explored as potential mucosal vaccine vectors due to their ability to elicit an immune response against expressed foreign antigens and to their safety. However, tools for monitoring LAB distribution and persistence at the mucosal surfaces are needed. Here, we characterize Lactiplantibacillus plantarum bacteria expressing the infrared fluorescent protein IRFP713 for exploring their in vivo distribution in the mucosa and potential use as a mucosal vaccine vector. This bacterial species is commonly used as a vaginal probiotic and was recently found to have a niche in the human nose. Three different fluorescent L. plantarum strains were obtained using the nisin-inducible pNZRK-IRFP713 plasmid which contains the nisRK genes, showing stable and constitutive expression of IRFP713 in vitro. One of these strains was further monitored in BALB/c mice using near-infrared fluorescence, indicating successful colonization of the nasal and vaginal mucosae for up to 72 h. This study thus provides a tool for the in vivo spatiotemporal monitoring of lactiplantibacilli, allowing non-invasive bacterial detection in these mucosal sites. KEY POINTS: • Stable and constitutive expression of the IRFP713 protein was obtained in different L. plantarum strains. • IRFP713 + L. plantarum 3.12.1 was monitored in vivo using near-infrared fluorescence. • Residence times observed after intranasal and vaginal inoculation were 24-72 h., (© 2022. The Author(s).)

Using heat maps provides frame and relevance to topics covered in physical acoustics courses as students can more easily visualize complex ideas and situations. Students can also form a much better understanding of the physical phenomena involved and build more advanced critical thinking when heat maps are used. It is the aim of the paper to provide ways for students to interact with heat maps by using two examples: first, the interaction of a plane wave (not only monochromatic) with an interface separating a fluid and a solid medium and, second, the interaction of an acoustic beam with such an interface (including a solid layer). These heat maps permit both to describe non-specular effects for the reflected acoustic beam due to the generation of a modal wave and, in the case of anisotropic media, highlight the difference between the direction predicted by Snell-Descartes law and that predicted by energy flux.

The aim of this paper is to briefly present ways to improve the interest of students who begin to attend physical acoustic courses and give examples of exercises (among many others) dedicated to the deepening of their training. Regarding the interest of students who are just beginning, two particular questions arise: how is the attention of these students gained? and how would the students be properly trained when starting out? An attempt to answer these questions is given at the beginning of the paper. Then, the paper continues with a brief presentation of some problems, which are extracted from a three-volume textbook that was published recently, precisely posed, and solved in detail analytically in an exact or approximate manner, even numerically, according to the three levels (bachelor, master, and Ph.D.) while offering an opportunity to deal extensively with the modeling of important topics in acoustics, which are treated as having several ways to be addressed.

The aim of this study was to characterize the evolution of gonorrhea in the general population by correlating epidemiological, genotypic, and antimicrobial resistance data of Neisseria gonorrhoeae isolates collected in northern Spain from 2014 to 2018. One hundred ninety-four strains underwent antimicrobial susceptibility testing and were genetically analyzed by N. gonorrhoeae multiantigen sequence typing. Increasing cases of gonococcal infections have been observed after 2015. Most occurred in male with urethritis. Sequence type (ST)-9972 and ST-1576, the predominant genotypes identified, have not been previously described as epidemic clones. Of great concern was the significant increase in azithromycin-resistant N. gonorrhoeae . More than 30% of these isolates were obtained from men who have sex with men (MSM). ST-12302 was the most prevalent clone among the azithromycin-resistant strains, and was also resistant to penicillin, ciprofloxacin, and tetracycline. This multidrug-resistant clone was exclusively isolated from MSM during 2018. The incidence rates of gonorrhea and azithromycin-resistant N. gonorrhoeae have significantly increased due to the emergence of new clones. ST-12302 has recently been recognized as an epidemic clone; therefore, its surveillance could be the key in controlling further dissemination of azithromycin resistance. These data highlight the need to perform local studies to update treatment guidelines and reinforce preventive measures against gonorrhea.