Acidithiobacillia class members originating at sites within the Pacific Ring of Fire and other tectonically active locations and description of the novel genus 'Igneacidithiobacillus'.

Recent studies have expanded the genomic contours of the Acidithiobacillia, highlighting important lacunae in our comprehension of the phylogenetic space occupied by certain lineages of the class. One such lineage is 'Igneacidithiobacillus', a novel genus-level taxon, represented by 'Igneacidithiobacillus copahuensis' VAN18-1T as its type species, along with two other uncultivated metagenome-assembled genomes (MAGs) originating from geothermally active sites across the Pacific Ring of Fire. In this study, we investigate the genetic and genomic diversity, and the distribution patterns of several uncharacterized Acidithiobacillia class strains and sequence clones, which are ascribed to the same 16S rRNA gene sequence clade. By digging deeper into this data and contributing to novel MAGs emerging from environmental studies in tectonically active locations, the description of this novel genus has been consolidated. Using state-of-the-art genomic taxonomy methods, we added to already recognized taxa, an additional four novel Candidate (Ca.) species, including 'Ca. Igneacidithiobacillus chanchocoensis' (mCHCt20-1TS), 'Igneacidithiobacillus siniensis' (S30A2T), 'Ca. Igneacidithiobacillus taupoensis' (TVZ-G3 TS), and 'Ca. Igneacidithiobacillus waiarikiensis' (TVZ-G4 TS). Analysis of published data on the isolation, enrichment, cultivation, and preliminary microbiological characterization of several of these unassigned or misassigned strains, along with the type species of the genus, plus the recoverable environmental data from metagenomic studies, allowed us to identify habitat preferences of these taxa. Commonalities and lineage-specific adaptations of the seven species of the genus were derived from pangenome analysis and comparative genomic metabolic reconstruction. The findings emerging from this study lay the groundwork for further research on the ecology, evolution, and biotechnological potential of the novel genus 'Igneacidithiobacillus'.

Smart Design of ZnFe and ZnFe@Fe Nanoparticles for MRI-Tracked Magnetic Hyperthermia Therapy: Challenging Classical Theories of Nanoparticles Growth and Nanomagnetism.

Iron Oxide Nanoparticles (IONPs) hold the potential to exert significant influence on fighting cancer through their theranostics capabilities as contrast agents (CAs) for magnetic resonance imaging (MRI) and as mediators for magnetic hyperthermia (MH). In addition, these capabilities can be improved by doping IONPs with other elements. In this work, the synthesis and characterization of single-core and alloy ZnFe novel magnetic nanoparticles (MNPs), with improved magnetic properties and more efficient magnetic-to-heat conversion, are reported. Remarkably, the results challenge classical nucleation and growth theories, which cannot fully predict the final size/shape of these nanoparticles and, consequently, their magnetic properties, implying the need for further studies to better understand the nanomagnetism phenomenon. On the other hand, leveraging the enhanced properties of these new NPs, successful tumor therapy by MH is achieved following their intravenous administration and tumor accumulation via the enhanced permeability and retention (EPR) effect. Notably, these results are obtained using a single low dose of MNPs and a single exposure to clinically suitable alternating magnetic fields (AMF). Therefore, as far as the authors are aware, for the first time, the successful application of intravenously administered MNPs for MRI-tracked MH tumor therapy in passively targeted tumor xenografts using clinically suitable conditions is demonstrated.

Sol-gel derived B2O3-CaO borate bioactive glasses with hemostatic, antibacterial and pro-angiogenic activities.

Sol-gel borate bioactive glasses (BGs) are promising ion-releasing biomaterials for wound healing applications. Here, we report the synthesis of a series of binary B2O3-CaO borate BGs (CaO ranging from 50 to 90 mol%) using a sol-gel-based method. The influence of CaO content in B2O3-CaO borate BG on morphology, structure and ion release behavior was investigated in detail. Reduced dissolution (ion release) and crystallization could be observed in borate BGs when CaO content increased, while the morphology was not significantly altered by increasing CaO content. Our results evidenced that the ion release behavior of borate BGs could be tailored by tuning the B2O3/CaO molar ratio. We also evaluated the in vitro cytotoxicity, hemostatic, antibacterial and angiogenic activities of borate BGs. Cytocompatibility was validated for all borate BGs. However, borate BGs exhibited composition-dependent hemostatic, antibacterial and angiogenic activities. Generally, higher contents of Ca in borate BGs facilitated hemostatic activity, while higher contents of B2O3 were beneficial for pro-angiogenic activity. The synthesized sol-gel-derived borate BGs are promising materials for developing advanced wound healing dressings, given their fast ion release behavior and favorable hemostatic, antibacterial and angiogenic activities.

Smartphone-based safety plan for suicidal crisis: The SmartCrisis 2.0 pilot study.

Here we present the findings of the pilot phase of the SmartCrisis 2.0 Randomized Clinical Trial. This pilot study aimed to explore the feasibility and acceptability of a safety plan contained in a smartphone app. Our sample consisted patients with a history of recent suicidal behaviour who installed a smartphone-based safety plan. To explore the satisfaction with of the safety plan, two patient satisfaction surveys were conducted: one qualitative and one quantitative. To explore the objective use of the safety plan, we gained access to texts contained in the safety plans completed by the patients. Participation rate was 77%, while 48.9% patients completed both satisfaction surveys at the end of the pilot phase. N = 105 successfully installed the safety plan. In a scale from 1 to 10, users rated the usefulness of the security plan at 7.4, the usability at 8.9, the degree to which they would recommend it to others at 8.6 and the overall satisfaction with the project including evaluations at 9.6. The most widely completed tab was warning signs. Feeling sad or lonely was the warning sign most commonly reported by patients. The second most completed tab was internal coping strategies. Walking or practicing any other exercise was the strategy most commonly resorted to. Our smartphone-based safety plan appears to be a feasible intervention. Data obtained from this pilot study showed high participation rates and high acceptability by patients. This, together with the general satisfaction with the project, supports its implementation in the clinical practice.

Developing a bioactive glass coated dental floss: antibacterial and mechanical evaluations.

In the present study, we investigated commercial dental floss coated with chitosan or chitosan + mesoporous bioactive glass nanoparticles (MBGNs) in order to determine the antimicrobial and mechanical properties of the newly fabricated flosses. Whereas these coatings showed notable ability to inhibit growth of both Gram (+) and Gram (-) bacteria after 24 h, the impact was negligible at 3 h. Furthermore, the tensile strength of the floss was improved by the addition of these layers, making it more durable and effective for cleaning between teeth. We therefore propose enhanced investigations of these composites since they demonstrate enormous potential in promoting oral health.

Pangenome-level analysis of nucleoid-associated proteins in the Acidithiobacillia class: insights into their functional roles in mobile genetic elements biology.

Mobile genetic elements (MGEs) are relevant agents in bacterial adaptation and evolutionary diversification. Stable appropriation of these DNA elements depends on host factors, among which are the nucleoid-associated proteins (NAPs). NAPs are highly abundant proteins that bind and bend DNA, altering its topology and folding, thus affecting all known cellular DNA processes from replication to expression. Even though NAP coding genes are found in most prokaryotic genomes, their functions in host chromosome biology and xenogeneic silencing are only known for a few NAP families. Less is known about the occurrence, abundance, and roles of MGE-encoded NAPs in foreign elements establishment and mobility. In this study, we used a combination of comparative genomics and phylogenetic strategies to gain insights into the diversity, distribution, and functional roles of NAPs within the class Acidithiobacillia with a special focus on their role in MGE biology. Acidithiobacillia class members are aerobic, chemolithoautotrophic, acidophilic sulfur-oxidizers, encompassing substantial genotypic diversity attributable to MGEs. Our search for NAP protein families (PFs) in more than 90 genomes of the different species that conform the class, revealed the presence of 1,197 proteins pertaining to 12 different NAP families, with differential occurrence and conservation across species. Pangenome-level analysis revealed 6 core NAP PFs that were highly conserved across the class, some of which also existed as variant forms of scattered occurrence, in addition to NAPs of taxa-restricted distribution. Core NAPs identified are reckoned as essential based on the conservation of genomic context and phylogenetic signals. In turn, various highly diversified NAPs pertaining to the flexible gene complement of the class, were found to be encoded in known plasmids or, larger integrated MGEs or, present in genomic loci associated with MGE-hallmark genes, pointing to their role in the stabilization/maintenance of these elements in strains and species with larger genomes. Both core and flexible NAPs identified proved valuable as markers, the former accurately recapitulating the phylogeny of the class, and the later, as seed in the bioinformatic identification of novel episomal and integrated mobile elements.

Cost-effectiveness analysis of PCV20 to prevent pneumococcal disease in the Canadian pediatric population.

This study assessed the cost-effectiveness of the 20-valent pneumococcal conjugate vaccine (PCV20) in Canadian infants aged <2 years versus the standard of care (SoC), a 13-valent pneumococcal conjugate vaccine (PCV13), or a potential 15-valent pneumococcal conjugate vaccine (PCV15). A decision-analytic Markov model was developed to compare PCV20 with PCV13 or PCV15 in a 2 + 1 schedule over 10 years. Vaccine effect estimates (direct and indirect) across all ages were informed by PCV13 clinical effectiveness and impact studies as well as PCV7 efficacy studies. Epidemiologic, clinical, health state utilities, utility decrements, cost per event, and list price data were from Canadian sources where available. Clinical and economic outcomes related to invasive pneumococcal disease (IPD), hospitalized and non-hospitalized pneumonia, and simple and complex otitis media (OM) were calculated for each strategy. Cost-effectiveness was evaluated from the publicly funded healthcare system perspective. Over 10 years, PCV20 versus PCV13 was estimated to avert over 11,000 IPD cases, 316,000 hospitalized and non-hospitalized pneumonia cases, 335,000 simple and complex OM cases, and 15,000 deaths, resulting in cost savings of over 3.2 billion Canadian dollars (CAD) and 47,000 more quality-adjusted life years (i.e. dominant strategy). Compared with PCV15, PCV20 was estimated to result in over 1.4 billion CAD in cost savings and 21,000 more QALYs (i.e. dominant strategy). PCV20 was dominant over both PCV13 and PCV15. Given broader serotype coverage, substantial incremental benefits and cost-savings, PCV20 should be considered as a replacement for the SoC in the publicly funded Canadian infant immunization program.

Assessing Formability and Failure of UHMWPE Sheets through SPIF: A Case Study in Medical Applications.

This work presents a comprehensive investigation of an experimental study conducted on ultra-high molecular weight polyethylene (UHMWPE) sheets using single point incremental forming (SPIF). The analysis is performed within a previously established research framework to evaluate formability and failure characteristics, including necking and fracture, in both conventional Nakajima tests and incremental sheet forming specimens. The experimental design of the SPIF tests incorporates process parameters such as spindle speed and step down to assess their impact on the formability of the material and the corresponding failure modes. The results indicate that a higher step down value has a positive effect on formability in the SPIF context. The study has identified the tool trajectory in SPIF as the primary influencing factor in the twisting failure mode. Implementing a bidirectional tool trajectory effectively reduced instances of twisting. Additionally, this work explores a medical case study that examines the manufacturing of a polyethylene liner device for a total hip replacement. This investigation critically analyses the manufacturing of plastic liner using SPIF, focusing on its formability and the elastic recovery exhibited by the material.

Influence of mobile genetic elements and insertion sequences in long- and short-term adaptive processes of Acidithiobacillus ferrooxidans strains.

The recent revision of the Acidithiobacillia class using genomic taxonomy methods has shown that, in addition to the existence of previously unrecognized genera and species, some species of the class harbor levels of divergence that are congruent with ongoing differentiation processes. In this study, we have performed a subspecies-level analysis of sequenced strains of Acidithiobacillus ferrooxidans to prove the existence of distinct sublineages and identify the discriminant genomic/genetic characteristics linked to these sublineages, and to shed light on the processes driving such differentiation. Differences in the genomic relatedness metrics, levels of synteny, gene content, and both integrated and episomal mobile genetic elements (MGE) repertoires support the existence of two subspecies-level taxa within A. ferrooxidans. While sublineage 2A harbors a small plasmid related to pTF5, this episomal MGE is absent in sublineage 2B strains. Likewise, clear differences in the occurrence, coverage and conservation of integrated MGEs are apparent between sublineages. Differential MGE-associated gene cargo pertained to the functional categories of energy metabolism, ion transport, cell surface modification, and defense mechanisms. Inferred functional differences have the potential to impact long-term adaptive processes and may underpin the basis of the subspecies-level differentiation uncovered within A. ferrooxidans. Genome resequencing of iron- and sulfur-adapted cultures of a selected 2A sublineage strain (CCM 4253) showed that both episomal and large integrated MGEs are conserved over twenty generations in either growth condition. In turn, active insertion sequences profoundly impact short-term adaptive processes. The ISAfe1 element was found to be highly active in sublineage 2A strain CCM 4253. Phenotypic mutations caused by the transposition of ISAfe1 into the pstC2 encoding phosphate-transport system permease protein were detected in sulfur-adapted cultures and shown to impair growth on ferrous iron upon the switch of electron donor. The phenotypic manifestation of the △pstC2 mutation, such as a loss of the ability to oxidize ferrous iron, is likely related to the inability of the mutant to secure the phosphorous availability for electron transport-linked phosphorylation coupled to iron oxidation. Depletion of the transpositional △pstC2 mutation occurred concomitantly with a shortening of the iron-oxidation lag phase at later transfers on a ferrous iron-containing medium. Therefore, the pstII operon appears to play an essential role in A. ferrooxidans when cells oxidize ferrous iron. Results highlight the influence of insertion sequences and both integrated and episomal mobile genetic elements in the short- and long-term adaptive processes of A. ferrooxidans strains under changing growth conditions.

Mussel-Inspired Polydopamine Composite Mesoporous Bioactive Glass Nanoparticles: An Exploration of Potential Metal-Ion Loading Platform and In Vitro Bioactivity.

Exploring new approaches to realize the possibility of incorporating biologically active elements into mesoporous silicate bioactive glass nanoparticles (MBG NPs) and guaranteeing their meso- structural integrity and dimensional stability has become an attractive and interesting challenge in biomaterials science. We present a postgrafting strategy for introducing different metal elements into MBG NPs. This strategy is mediated by polydopamine (PDA) coating, achieving uniform loading of copper or copper-cobalt on the particles efficiently and ensuring the stability of MBG NPs in terms of particle size, mesoporous structure, and chemical structure. However, the PDA coating reduced the ion-binding free energy of the MBG NPs for calcium and phosphate ions, resulting in the deposition of minimal CaP clusters on the PDA@MBG NP surface when immersed for 7 days in simulated body fluid, indicating the absence of hydroxyapatite mineralization.

Correlación del ácido úrico con el grosor de la íntima media de la carótida en adolescentes con obesidad / Correlation of uric acid with carotid intima media thickness in obese adolescents

Introducción: la obesidad en la población pediátrica es un problema de salud pública. Se ha demostrado la correlación del ácido úrico y el grosor de la íntima media de la carótida en adultos. Objetivo: identificar la correlación del ácido úrico y el grosor de la íntima media de la carótida en adolescentes con obesidad. Material y métodos: se realizó un estudio observacional, transversal. Se incluyeron pacientes de diez a 16 años con diagnóstico de obesidad. Se determinó ácido úrico, perfil de lípidos y grosor de la íntima media carotidea. En el análisis estadístico, se correlacionó el grosor de la íntima media carotídea con los niveles de ácido úrico a través del coeficiente de correlación de Spearman. Resultados: se incluyeron 169 adolescentes con una mediana para la edad de 13 años, sin predominio de sexo. Se identificó una correlación positiva del ácido úrico con el grosor de la íntima media carotídea (r = 0,242, p = 0,001). Al estratificarse de acuerdo con el sexo, no hubo correlación en las mujeres (r = -0,187, p = 0,074), mientras que en los hombres aumentó (r = 0,36, p = 0,001) y por estadio puberal, los adolescentes varones púberes tuvieron una correlación positiva (p = 0,384, p = 0,002). Conclusión: se identificó una correlación positiva débil entre el grosor de la íntima de la carótida y el ácido úrico en adolescentes con obesidad. (AU)

Introduction: obesity in the pediatric population is a public health problem. The correlation of uric acid and carotid intima media thickness in adults has been demonstrated.Objective: to identify the correlation of uric acid and carotid intima media thickness in adolescents with obesity.Material and methods: an observational, cross-sectional study was carried out. Patients aged ten to 16 years with a diagnosis of obesity were included. Uric acid, lipid profile and carotid intima media thickness were determined. In relation to the statistical analysis, carotid intima media thickness was correlated with uric acid levels through Spearman's correlation coefficient. Results: one hundred and sixty-nine adolescents were included with a median age of 13 years, without predominance of sex. A positive correlation of uric acid with carotid intima media thickness was identified (r = 0.242, p = 0.001). When stratified according to sex, there was no correlation in women (r = -0.187, p = 0.074), while in men it increased (r = 0.36, p = 0.001) and by pubertal stage, pubertal male adolescents had a positive correlation (p = 0.384, p = 0.002).Conclusion: a weak positive correlation was identified between carotid intimal thickness and uric acid in obese adolescents. (AU)

[Correlation of uric acid with carotid intima media thickness in obese adolescents]. / Correlación del ácido úrico con el grosor de la íntima media de la carótida en adolescentes con obesidad.

Introduction: Introduction: obesity in the pediatric population is a public health problem. The correlation of uric acid and carotid intima media thickness in adults has been demonstrated. Objective: to identify the correlation of uric acid and carotid intima media thickness in adolescents with obesity. Material and methods: an observational, cross-sectional study was carried out. Patients aged ten to 16 years with a diagnosis of obesity were included. Uric acid, lipid profile and carotid intima media thickness were determined. In relation to the statistical analysis, carotid intima media thickness was correlated with uric acid levels through Spearman's correlation coefficient. Results: one hundred and sixty-nine adolescents were included with a median age of 13 years, without predominance of sex. A positive correlation of uric acid with carotid intima media thickness was identified (r = 0.242, p = 0.001). When stratified according to sex, there was no correlation in women (r = -0.187, p = 0.074), while in men it increased (r = 0.36, p = 0.001) and by pubertal stage, pubertal male adolescents had a positive correlation (p = 0.384, p = 0.002). Conclusion: a weak positive correlation was identified between carotid intimal thickness and uric acid in obese adolescents.

Introducción: Introducción: la obesidad en la población pediátrica es un problema de salud pública. Se ha demostrado la correlación del ácido úrico y el grosor de la íntima media de la carótida en adultos. Objetivo: identificar la correlación del ácido úrico y el grosor de la íntima media de la carótida en adolescentes con obesidad. Material y métodos: se realizó un estudio observacional, transversal. Se incluyeron pacientes de diez a 16 años con diagnóstico de obesidad. Se determinó ácido úrico, perfil de lípidos y grosor de la íntima media carotidea. En el análisis estadístico, se correlacionó el grosor de la íntima media carotídea con los niveles de ácido úrico a través del coeficiente de correlación de Spearman. Resultados: se incluyeron 169 adolescentes con una mediana para la edad de 13 años, sin predominio de sexo. Se identificó una correlación positiva del ácido úrico con el grosor de la íntima media carotídea (r = 0,242, p = 0,001). Al estratificarse de acuerdo con el sexo, no hubo correlación en las mujeres (r = -0,187, p = 0,074), mientras que en los hombres aumentó (r = 0,36, p = 0,001) y por estadio puberal, los adolescentes varones púberes tuvieron una correlación positiva (p = 0,384, p = 0,002). Conclusión: se identificó una correlación positiva débil entre el grosor de la íntima de la carótida y el ácido úrico en adolescentes con obesidad.

Burden of Acute-Care Hospitalization for Community-Acquired Pneumonia in Canadian Adults Aged 50 Years or Older: Focusing on Most Responsible Diagnosis Tells Only Part of the Story.

The burden of all-cause community-acquired pneumonia (CAP), including pneumococcal pneumonia, is typically estimated using ICD codes where pneumonia is coded as the most responsible diagnosis (MRDx). Pneumonia may also be coded as other than most responsible diagnosis (ODx) based on administrative and reimbursement criteria. Analyses including pneumonia as MRDx only likely underestimate hospitalized CAP incidence. The aim of this study was to estimate the burden of hospitalized all-cause CAP in Canada and to assess the contribution of ODx-coded cases to the overall disease burden. This longitudinal retrospective study obtained data from the Canadian Institutes of Health Information (CIHI) for adults 50+ years hospitalized for CAP between 1 April 2009 and 31 March 2019. Cases were identified as those where pneumonia was either diagnosis code type M (MRDx) or pre-admit comorbidity type 1 (ODx). Reported outcomes include pneumonia incidence rate, in-hospital mortality, hospital length of stay, and cost. Outcomes were stratified by age group, case coding, and comorbidity. Between 2009-2010 and 2018-2019, CAP incidence increased from 805.66 to 896.94 per 100,000. During this time, 55-58% of cases had pneumonia coded as ODx. Importantly, these cases had longer hospital stays, higher in-hospital mortality, and higher cost of hospitalization. The burden of CAP remains substantial and is significantly greater than that estimated by solely focusing on MRDx-coded cases. Our findings have implications for policy decision making related to current and future immunization programs.

Global phylogenomic novelty of the Cas1 gene from hot spring microbial communities.

The Cas1 protein is essential for the functioning of CRISPR-Cas adaptive systems. However, despite the high prevalence of CRISPR-Cas systems in thermophilic microorganisms, few studies have investigated the occurrence and diversity of Cas1 across hot spring microbial communities. Phylogenomic analysis of 2,150 Cas1 sequences recovered from 48 metagenomes representing hot springs (42-80°C, pH 6-9) from three continents, revealed similar ecological diversity of Cas1 and 16S rRNA associated with geographic location. Furthermore, phylogenetic analysis of the Cas1 sequences exposed a broad taxonomic distribution in thermophilic bacteria, with new clades of Cas1 homologs branching at the root of the tree or at the root of known clades harboring reference Cas1 types. Additionally, a new family of casposases was identified from hot springs, which further completes the evolutionary landscape of the Cas1 superfamily. This ecological study contributes new Cas1 sequences from known and novel locations worldwide, mainly focusing on under-sampled hot spring microbial mat taxa. Results herein show that circumneutral hot springs are environments harboring high diversity and novelty related to adaptive immunity systems.

Influence of Copper-Strontium Co-Doping on Bioactivity, Cytotoxicity and Antibacterial Activity of Mesoporous Bioactive Glass.

Mesoporous bioactive glass (MBG) is an extensively studied biomaterial used for the healing of bone defects. Its biological applications can be tailored by introducing metallic ions, such as strontium (Sr) and copper (Cu), which can enhance its functionalities, including osteogenetic, angiogenetic and antibacterial functionalities. In this study, Cu and Sr ions were co-doped (ratio 1:1) with x = 0.5, 1 and 2 mol% each in glass with an intended nominal composition of 80SiO2-(15-2x)CaO-5P2O5-xCuO-xSrO and synthesized with an evaporation-induced self-assembly (EISA)-based sol-gel technique. XRD confirmed the amorphous nature of the glass, while compositional analysis using ICP-OES confirmed the presence of dopant ions with the required amounts. A TEM study of the MBG powders showed fringes that corresponded to the formation of a highly ordered mesoporous structure. The Cu-Sr-doped MBG showed a positive effect on apatite formation when immersed in SBF, although the release of Cu and Sr ions was relatively slow for 1 mol% of each co-dopant, which signified a stable network structure in the glass. The impact of the Cu and Sr ions on the osteoblast-like cell line MG-63 was assessed. At the particle concentrations of 1 wt./vol.% or lower, the cell viability was above 50%. An antibacterial test was conducted against Gram-negative E. coli and Gram-positive S. aureus bacteria. With a sequential increase in the co-doped ion content in the glass, the zone of inhibition for bacteria increased. The results suggest that the doping of MBG with Cu and Sr ions at up to 2 mol% can result in tailored sustained release of ions to enhance the applicability of the studied glass as a functional biomaterial for bone regeneration applications.

Effect of Boron-Doped Mesoporous Bioactive Glass Nanoparticles on C2C12 Cell Viability and Differentiation: Potential for Muscle Tissue Application.

Mesoporous bioactive glasses (MBGs) exhibit a high surface area and a highly ordered mesoporous structure. MBGs have potential for both hard and soft tissue engineering applications. MBGs may be doped with biologically active ions to tailor their biological activity. Boron is being widely studied as a dopant of bioactive glasses. Recently, research has demonstrated the potential of boron-containing bioactive glasses for muscle regeneration. In this study, boron-containing MBGs, 10B-MBG and 18B-MBG nanoparticles, were produced by a microemulsion-assisted sol-gel approach for potential muscle regeneration applications. First, X-ray diffraction (XRD), Fourier transform infrared (FTIR), and energy-dispersive X-ray spectroscopy (EDX) analyses were conducted to study the chemical structure and composition of the nanoparticles. To examine the nanoparticle morphology, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images were analyzed. Both SEM images and particle size distribution determined by dynamic light scattering (DLS) indicated a decrease of the average particle size after boron doping. TEM images indicated a slit-shaped mesoporous structure of nanoparticles for all compositions. The ζ potential was measured, and a negative surface charge was found for all study groups due to the presence of silanol groups. Cytocompatibility and fluorescence microscopy studies were also carried out. The results indicated that low concentrations (0.1 and 1 mg mL-1) of all MBG nanoparticles led to high viability of C2C12 cells. Fluorescence microscopy images indicated that at lower nanoparticle concentrations (0.1 and 1 mg mL-1), C2C12 cells appeared to differentiate into myotubes, which was indicated by a spindle-shaped morphology. For 10 mg mL-1 concentration of nanoparticles, C2C12 cells had a lower aspect ratio (estimated qualitatively by inspection of the images), which implied a lower degree of differentiation. Boron-doped MBG nanoparticles in reduced concentrations are suitable to induce differentiation of C2C12 cells into myotubes, indicating their potential for applications in muscle tissue repair.

Asociación del fitness cardiorrespiratorio con marcadores de adiposidad corporal: estudio de corte transversal de la Encuesta Nacional de Salud Chile 2016-2017 / Association of cardiorespiratory fitness with adiposity markers

BACKGROUND: Cardiorespiratory fitness (CRF) is inversely associated with metabolic diseases and adiposity markers. Aim: To assess the association of CRF with body mass index (BMI), waist circumference (WC) and obesity in a representative sample of the Chilean population. MATERIAL AND METHODS: Data from 5,958 participants in the Chilean National Health Survey 2016-1027 aged 15 years or above were analyzed. CRF was estimated by an equation that included sociodemographic, anthropometric and health-related data and expressed in metabolic equivalent units (METs). The association between CRF and adiposity was assessed using linear and Poisson regression models and the results were presented as Prevalence Ratio (PR). RESULTS: One MET increment in CRF was associated with a 3.27 kg/m2 (95% confidence intervals (CI): -3.35; -3.2) and 4.56 kg/m2 (95% CI: -4.67; -4.46) lower BMI in men and women, respectively. Waist circumference was 6.7 cm [95% CI: -6.98; -6.42] and 9 cm [95% CI: -9.33; -8.67] lower per 1-MET increment in CRF. With one MET increment, the probability of being obese was 34% (PR = 0.66 [95%CI: 0.63; 0.69]) and 36% (PR = 0.64 [95%CI: 0.61; 0.67]) lower in men and women, respectively. The probability of having a central obesity was 26% (PR = 0.74 [95%CI: 0.71; 0.77]) and 30% (PR = 0.70 [95%CI: 0.68; 0.73]) lower in men and women, respectively. Conclusions: A higher estimated CRF was associated with lower adiposity levels and a lower risk of being obese in both men and women. Public health policies aiming to increase physical activity are needed to increase the CRF of the Chilean population.

Influence of Femtosecond Laser Modification on Biomechanical and Biofunctional Behavior of Porous Titanium Substrates.

Bone resorption and inadequate osseointegration are considered the main problems of titanium implants. In this investigation, the texture and surface roughness of porous titanium samples obtained by the space holder technique were modified with a femtosecond Yb-doped fiber laser. Different percentages of porosity (30, 40, 50, and 60 vol.%) and particle range size (100-200 and 355-500 µm) were compared with fully-dense samples obtained by conventional powder metallurgy. After femtosecond laser treatment the formation of a rough surface with micro-columns and micro-holes occurred for all the studied substrates. The surface was covered by ripples over the micro-metric structures. This work evaluates both the influence of the macro-pores inherent to the spacer particles, as well as the micro-columns and the texture generated with the laser, on the wettability of the surface, the cell behavior (adhesion and proliferation of osteoblasts), micro-hardness (instrumented micro-indentation test, P-h curves) and scratch resistance. The titanium sample with 30 vol.% and a pore range size of 100-200 µm was the best candidate for the replacement of small damaged cortical bone tissues, based on its better biomechanical (stiffness and yield strength) and biofunctional balance (bone in-growth and in vitro osseointegration).

Anticoncepción de emergencia, evaluación de conocimiento en adolescentes / Emergency contraception, knowledge assessment in teenagers / Contracepção de emergência, avaliação de conhecimento em adolescentes

El inicio sexual temprano, conlleva numerosos riesgos como embarazos precoces o enfermedades de transmisión sexual, abortos; por ello, la importancia de que los adolescentes conozcan la anticoncepción de emergencia, sobre todo, para la prevención del embarazo no deseado y las secuelas del aborto. Objetivo. Describir la anticoncepción de emergencia y la evaluación de su conocimiento en adolescentes. Materiales y métodos. Revisión sistemática, basado en criterios de inclusión y exclusión, se realizó la búsqueda de documentos entre los años 2020 y 2021, de las bases de datos PubMed, Cochrane, Science Direct, Redalyc, Scielo. Se usaron las palabras clave de los DeCS y MeSH; además, se utilizó los operadores booleanos AND, OR. Se obtuvieron 18 artículos para elaborar esta investigación. Resultados. El uso de anticoncepción de emergencia (AE) varía entre el 10,6% hasta un 60% en dependencia de la población estudiada, además, gran parte de los factores de rechazo radican en una desinformación acerca de su mecanismo de acción y a la estigmatización de la misma, el cual es visto como un método abortivo. El nivel de conocimiento acerca de la AE es baja, destacando factores como el hecho de asistir a un colegio de menor nivel académico y ser inmigrante, los que se asocian con un menor conocimiento de la misma. Conclusiones. Pese a los esfuerzos por garantizar una salud sexual y reproductiva los niveles de conocimiento sobre el AE son bajos, siendo reflejado en la prevalencia de utilización y en los factores que limitan su adquisición y uso.

Early sexual initiation carries numerous risks such as early pregnancy or sexually transmitted diseases, abortions; therefore, it is important for adolescents to know about emergency contraception, especially for the prevention of unwanted pregnancy and the sequelae of abortion. Objective. To describe emergency contraception and the evaluation of its knowledge in adolescents. Materials and methods. Systematic review, based on inclusion and exclusion criteria, we searched for documents between 2020 and 2021, from PubMed, Cochrane, Science Direct, Redalyc, Scielo databases. DeCS and MeSH keywords were used; in addition, the Boolean operators AND, OR were used. Eighteen articles were obtained to prepare this research. Results. The use of emergency contraception (EC) varies from 10.6% to 60% depending on the population studied. In addition, a large part of the rejection factors lie in misinformation about its mechanism of action and its stigmatization, which is seen as an abortive method. The level of knowledge about EC is low, with factors such as the fact of attending a school with a lower academic level and being an immigrant being associated with a lower level of knowledge. Conclusions. Despite the efforts to guarantee sexual and reproductive health, the levels of knowledge about EC are low, being reflected in the prevalence of use and in the factors that limit its acquisition and use.

A iniciação sexual precoce acarreta inúmeros riscos, como gravidez precoce ou doenças sexualmente transmissíveis, abortos; portanto, é importante que as adolescentes estejam cientes da contracepção de emergência, especialmente para a prevenção da gravidez indesejada e das conseqüências do aborto. Objetivo. Para descrever a anticoncepção de emergência e a avaliação de seus conhecimentos em adolescentes. Materiais e métodos. Revisão sistemática, baseada em critérios de inclusão e exclusão, pesquisamos documentos entre 2020 e 2021, nas bases de dados PubMed, Cochrane, Science Direct, Redalyc, Scielo. Foram utilizadas as palavras-chave DeCS e MeSH; além disso, foram utilizados os operadores Booleanos AND, OR. Dezoito artigos foram obtidos para esta pesquisa. Resultados. O uso da anticoncepção de emergência (CE) varia de 10,6% a 60% dependendo da população estudada. Além disso, uma grande parte dos fatores de rejeição reside na desinformação sobre seu mecanismo de ação e sua estigmatização, o que é visto como um método abortivo. O nível de conhecimento sobre CE é baixo, com fatores como o fato de freqüentar uma escola com um nível acadêmico inferior e ser um imigrante sendo associado a um nível de conhecimento inferior. Conclusões. Apesar dos esforços para garantir a saúde sexual e reprodutiva, os níveis de conhecimento sobre CE são baixos, como refletido na prevalência do uso e nos fatores que limitam sua aquisição e uso.

Iron-Gold Nanoflowers: A Promising Tool for Multimodal Imaging and Hyperthermia Therapy.

The development of nanoplatforms prepared to perform both multimodal imaging and combined therapies in a single entity is a fast-growing field. These systems are able to improve diagnostic accuracy and therapy success. Multicomponent Nanoparticles (MCNPs), composed of iron oxide and gold, offer new opportunities for Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) diagnosis, as well as combined therapies based on Magnetic Hyperthermia (MH) and Photothermal Therapy (PT). In this work, we describe a new seed-assisted method for the synthesis of Au@Fe Nanoparticles (NPs) with a flower-like structure. For biomedical purposes, Au@Fe NPs were functionalized with a PEGylated ligand, leading to high colloidal stability. Moreover, the as-obtained Au@Fe-PEG NPs exhibited excellent features as both MRI and CT Contrast Agents (CAs), with high r2 relaxivity (60.5 mM-1⋅s-1) and X-ray attenuation properties (8.8 HU mM-1⋅HU). In addition, these nanoflowers presented considerable energy-to-heat conversion under both Alternating Magnetic Fields (AMFs) (∆T ≈ 2.5 °C) and Near-Infrared (NIR) light (∆T ≈ 17 °C). Finally, Au@Fe-PEG NPs exhibited very low cytotoxicity, confirming their potential for theranostics applications.