Dual ifgMosaic: A Versatile Method for Multispectral and Combinatorial Mosaic Gene-Function Analysis.

Improved methods for manipulating and analyzing gene function have provided a better understanding of how genes work during organ development and disease. Inducible functional genetic mosaics can be extraordinarily useful in the study of biological systems; however, this experimental approach is still rarely used in vertebrates. This is mainly due to technical difficulties in the assembly of large DNA constructs carrying multiple genes and regulatory elements and their targeting to the genome. In addition, mosaic phenotypic analysis, unlike classical single gene-function analysis, requires clear labeling and detection of multiple cell clones in the same tissue. Here, we describe several methods for the rapid generation of transgenic or gene-targeted mice and embryonic stem (ES) cell lines containing all the necessary elements for inducible, fluorescent, and functional genetic mosaic (ifgMosaic) analysis. This technology enables the interrogation of multiple and combinatorial gene function with high temporal and cellular resolution.

Questioning the fetal microbiome illustrates pitfalls of low-biomass microbial studies.

Whether the human fetus and the prenatal intrauterine environment (amniotic fluid and placenta) are stably colonized by microbial communities in a healthy pregnancy remains a subject of debate. Here we evaluate recent studies that characterized microbial populations in human fetuses from the perspectives of reproductive biology, microbial ecology, bioinformatics, immunology, clinical microbiology and gnotobiology, and assess possible mechanisms by which the fetus might interact with microorganisms. Our analysis indicates that the detected microbial signals are likely the result of contamination during the clinical procedures to obtain fetal samples or during DNA extraction and DNA sequencing. Furthermore, the existence of live and replicating microbial populations in healthy fetal tissues is not compatible with fundamental concepts of immunology, clinical microbiology and the derivation of germ-free mammals. These conclusions are important to our understanding of human immune development and illustrate common pitfalls in the microbial analyses of many other low-biomass environments. The pursuit of a fetal microbiome serves as a cautionary example of the challenges of sequence-based microbiome studies when biomass is low or absent, and emphasizes the need for a trans-disciplinary approach that goes beyond contamination controls by also incorporating biological, ecological and mechanistic concepts.

Arterialization requires the timely suppression of cell growth.

The formation of arteries is thought to occur by the induction of a highly conserved arterial genetic programme in a subset of vessels that will later experience an increase in oxygenated blood flow1,2. The initial steps of arterial specification require both the VEGF and Notch signalling pathways3-5. Here, we combine inducible genetic mosaics and transcriptomics to modulate and define the function of these signalling pathways in cell proliferation, arteriovenous differentiation and mobilization. We show that endothelial cells with high levels of VEGF or Notch signalling are intrinsically biased to mobilize and form arteries; however, they are not genetically pre-determined, and can also form veins. Mechanistically, we found that increased levels of VEGF and Notch signalling in pre-arterial capillaries suppresses MYC-dependent metabolic and cell-cycle activities, and promotes the incorporation of endothelial cells into arteries. Mosaic lineage-tracing studies showed that endothelial cells that lack the Notch-RBPJ transcriptional activator complex rarely form arteries; however, these cells regained the ability to form arteries when the function of MYC was suppressed. Thus, the development of arteries does not require the direct induction of a Notch-dependent arterial differentiation programme, but instead depends on the timely suppression of endothelial cell-cycle progression and metabolism, a process that precedes arterial mobilization and complete differentiation.

iSuRe-HadCre is an essential tool for effective conditional genetics.

Methods for modifying gene function at high spatiotemporal resolution in mice have revolutionized biomedical research, with Cre-loxP being the most widely used technology. However, the Cre-loxP technology has several drawbacks, including weak activity, leakiness, toxicity, and low reliability of existing Cre-reporters. This is mainly because different genes flanked by loxP sites (floxed) vary widely in their sensitivity to Cre-mediated recombination. Here, we report the generation, validation, and utility of iSuRe-HadCre, a new dual Cre-reporter and deleter mouse line that avoids these drawbacks. iSuRe-HadCre achieves this through a novel inducible dual-recombinase genetic cascade that ensures that cells expressing a fluorescent reporter had only transient Cre activity, that is nonetheless sufficient to effectively delete floxed genes. iSuRe-HadCre worked reliably in all cell types and for the 13 floxed genes tested. This new tool will enable the precise, efficient, and trustworthy analysis of gene function in entire mouse tissues or in single cells.

Integrated post-genomic cell wall analysis reveals floating biofilm formation associated with high expression of flocculins in the pathogen Pichia kudriavzevii.

The pathogenic yeast Pichia kudriavzevii, previously known as Candida krusei, is more distantly related to Candida albicans than clinically relevant CTG-clade Candida species. Its cell wall, a dynamic organelle that is the first point of interaction between pathogen and host, is relatively understudied, and its wall proteome remains unidentified to date. Here, we present an integrated study of the cell wall in P. kudriavzevii. Our comparative genomic studies and experimental data indicate that the general structure of the cell wall in P. kudriavzevii is similar to Saccharomyces cerevisiae and C. albicans and is comprised of ß-1,3-glucan, ß-1,6-glucan, chitin, and mannoproteins. However, some pronounced differences with C. albicans walls were observed, for instance, higher mannan and protein levels and altered protein mannosylation patterns. Further, despite absence of proteins with high sequence similarity to Candida adhesins, protein structure modeling identified eleven proteins related to flocculins/adhesins in S. cerevisiae or C. albicans. To obtain a proteomic comparison of biofilm and planktonic cells, P. kudriavzevii cells were grown to exponential phase and in static 24-h cultures. Interestingly, the 24-h static cultures of P. kudriavzevii yielded formation of floating biofilm (flor) rather than adherence to polystyrene at the bottom. The proteomic analysis of both conditions identified a total of 33 cell wall proteins. In line with a possible role in flor formation, increased abundance of flocculins, in particular Flo110, was observed in the floating biofilm compared to exponential cells. This study is the first to provide a detailed description of the cell wall in P. kudriavzevii including its cell wall proteome, and paves the way for further investigations on the importance of flor formation and flocculins in the pathogenesis of P. kudriavzevii.

Heterogeneity of SOS response expression in clinical isolates of Escherichia coli influences adaptation to antimicrobial stress.

In recent years, new evidence has shown that the SOS response plays an important role in the response to antimicrobials, with involvement in the generation of clinical resistance. Here we evaluate the impact of heterogeneous expression of the SOS response in clinical isolates of Escherichia coli on response to the fluoroquinolone, ciprofloxacin. In silico analysis of whole genome sequencing data showed remarkable sequence conservation of the SOS response regulators, RecA and LexA. Despite the genetic homogeneity, our results revealed a marked differential heterogeneity in SOS response activation, both at population and single-cell level, among clinical isolates of E. coli in the presence of subinhibitory concentrations of ciprofloxacin. Four main stages of SOS response activation were identified and correlated with cell filamentation. Interestingly, there was a correlation between clinical isolates with higher expression of the SOS response and further progression to resistance. This heterogeneity in response to DNA damage repair (mediated by the SOS response) and induced by antimicrobial agents could be a new factor with implications for bacterial evolution and survival contributing to the generation of antimicrobial resistance.

Heart Failure With Preserved Ejection Fraction: Heterogeneous Syndrome, Diverse Preclinical Models.

Heart failure with preserved ejection fraction (HFpEF) represents one of the greatest challenges facing cardiovascular medicine today. Despite being the most common form of heart failure worldwide, there has been limited success in developing therapeutics for this syndrome. This is largely due to our incomplete understanding of the biology driving its systemic pathophysiology and the heterogeneity of clinical phenotypes, which are increasingly being recognized as distinct HFpEF phenogroups. Development of efficacious therapeutics fundamentally relies on robust preclinical models that not only faithfully recapitulate key features of the clinical syndrome but also enable rigorous investigation of putative mechanisms of disease in the context of clinically relevant phenotypes. In this review, we propose a preclinical research strategy that is conceptually grounded in model diversification and aims to better align with our evolving understanding of the heterogeneity of clinical HFpEF. Although heterogeneity is often viewed as a major obstacle in preclinical HFpEF research, we challenge this notion and argue that embracing it may be the key to demystifying its pathobiology. Here, we first provide an overarching guideline for developing HFpEF models through a stepwise approach of comprehensive cardiac and extra-cardiac phenotyping. We then present an overview of currently available models, focused on the 3 leading phenogroups, which are primarily based on aging, cardiometabolic stress, and chronic hypertension. We discuss how well these models reflect their clinically relevant phenogroup and highlight some of the more recent mechanistic insights they are providing into the complex pathophysiology underlying HFpEF.

Corelease of Genotoxic Polycyclic Aromatic Hydrocarbons and Nanoparticles from a Commercial Aircraft Jet Engine - Dependence on Fuel and Thrust.

Jet engines are important contributors to global CO2 emissions and release enormous numbers of ultrafine particles into different layers of the atmosphere. As a result, aviation emissions are affecting atmospheric chemistry and promote contrail and cloud formation with impacts on earth's radiative balance and climate. Furthermore, the corelease of nanoparticles together with carcinogenic polycyclic aromatic hydrocarbons (PAHs) affects air quality at airports. We studied exhausts of a widely used turbofan engine (CFM56-7B26) operated at five static thrust levels (idle, 7, 30, 65, and 85%) with conventional Jet A-1 fuel and a biofuel blend composed of hydro-processed esters and fatty acids (HEFA). The particles released, the chemical composition of condensable material, and the genotoxic potential of these exhausts were studied. At ground operation, particle number emissions of 3.5 and 0.5 × 1014 particles/kg fuel were observed with highest genotoxic potentials of 41300 and 8800 ng toxicity equivalents (TEQ)/kg fuel at idle and 7% thrust, respectively. Blending jet fuel with HEFA lowered PAH and particle emissions by 7-34% and 65-67% at idle and 7% thrust, respectively, indicating that the use of paraffin-rich biofuels is an effective measure to reduce the exposure of airport personnel to nanoparticles coated with genotoxic PAHs (Trojan horse effect).

Diagnosis of peripartum depression disorder: A state-of-the-art approach from the COST Action Riseup-PPD.

BACKGROUND: Peripartum depression (PPD) is a major depression disorder (MDD) episode with onset during pregnancy or within four weeks after childbirth, as defined in DSM-5. However, research suggests that PPD may be a distinct diagnosis. The goal of this study was to summarize the similarities and differences between PPD and MDD by synthesizing the current research on PPD diagnosis concerning different clinical features and give directions for improving diagnosis of PPD in clinical practice. METHODS: To lay the groundwork for this narrative review, several databases were searched using general search phrases on PPD and its components of clinical diagnosis. RESULTS: When compared to MDD, peripartum depression exhibits several distinct characteristics. PPD manifests with a variety of symptoms, i.e., more anxiety, psychomotor symptoms, obsessive thoughts, impaired concentration, fatigue and loss of energy, but less sad mood and suicidal ideation, compared to MDD. Although PPD and MDD prevalence rates are comparable, there are greater cross-cultural variances for PPD. Additionally, PPD has some distinct risk factors and mechanisms such as distinct ovarian tissue expression, premenstrual syndrome, unintended pregnancy, and obstetric complications. CONCLUSION: There is a need for more in-depth research comparing MDD with depression during pregnancy and the entire postpartum year. The diagnostic criteria should be modified, particularly with (i) addition of specific symptoms (i.e., anxiety), (ii) onset specifier extending to the first year following childbirth, (iii) and change the peripartum onset specifier to either "pregnancy onset" or "postpartum onset". Diagnostic criteria for PPD are further discussed.

Hygiene-based measures for the prevention of cytomegalovirus infection in pregnant women: a systematic review.

BACKGROUND: Human Cytomegalovirus (HCMV) is the most frequent congenital infection worldwide causing important sequelae. However, no vaccine or antiviral treatments are currently available, thus interventions are restricted to behavioral measures. The aim of this systematic review was to assess evidence from available intervention studies using hygiene-based measures to prevent HCMV infection during pregnancy. METHODS: Studies published from 1972 to 2023 were searched in Medline, PsycInfo, and Clinical Trials (PROSPERO, CRD42022344840) according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Methodological quality was assessed by two authors, using ROBE-2 and MINORS. RESULTS: After reviewing 6 selected articles, the outcome analysis suggested that implementation of hygiene-based interventions during pregnancy prevent, to some extent, the acquisition of congenital HCMV. CONCLUSIONS: However, these conclusions are based on limited and low-quality evidence available from few studies using this type of intervention in clinical practice. Thus, it would be necessary to perform effective and homogeneous intervention studies using hygiene-based measures, evaluated in high-quality randomized controlled trials (RCTs).

Identification of population-informative markers from high-density genotyping data through combined feature selection and machine learning algorithms: Application to European autochthonous and cosmopolitan pig breeds.

Large genotyping datasets, obtained from high-density single nucleotide polymorphism (SNP) arrays, developed for different livestock species, can be used to describe and differentiate breeds or populations. To identify the most discriminating genetic markers among thousands of genotyped SNPs, a few statistical approaches have been proposed. In this study, we applied the Boruta algorithm, a wrapper of the machine learning random forest algorithm, on a database of 23 European pig breeds (20 autochthonous and three cosmopolitan breeds) genotyped with a 70k SNP chip, to pre-select informative SNPs. To identify different sets of SNPs, these pre-selected markers were then ranked with random forest based on their mean decrease accuracy and mean decrease gene indexes. We evaluated the efficiency of these subsets for breed classification and the usefulness of this approach to detect candidate genes affecting breed-specific phenotypes and relevant production traits that might differ among breeds. The lowest overall classification error (2.3%) was reached with a subpanel including only 398 SNPs (ranked based on their mean decrease accuracy), with no classification error in seven breeds using up to 49 SNPs. Several SNPs of these selected subpanels were in genomic regions in which previous studies had identified signatures of selection or genes associated with morphological or production traits that distinguish the analysed breeds. Therefore, even if these approaches have not been originally designed to identify signatures of selection, the obtained results showed that they could potentially be useful for this purpose.

Performance of oxygenation indices and risk scores to predict invasive mechanical ventilation and mortality in COVID-19.

BACKGROUND: Information on the performance of oxygenation indices (OIs) and risk scores in patients requiring invasive mechanical ventilation (IMV) is limited. We determine the performance of the OIs and risk scores in hospitalized patients with COVID-19 to predict the requirement of IMV and death at 28 days after admission. METHODS: A retrospective study of diagnostic tests in patients admitted to the emergency department, hospitalization, and intensive care unit diagnosed with COVID-19. The receiver operating characteristic curve (ROC-curve) were built with the OIs and risk scores to predict IMV and mortality. RESULTS: A total of 1402 subjects entered the final analysis, of whom 19.5% (274/1402) received IMV and 23.0% (323/1402) died at 28 days. The ROC-curve of the delta PaO2/FiO2 ratio for the requirement of IMV and mortality at 28-day was 0.589 (95% CI: 0.546-0.632) and 0.567 (95% CI: 0.526-0.608), respectively. PaO2/FiO2 ≤ 300 shows a ROC curve of 0.669 (95% CI: 0.628-0.711) to predict IMV. PaO2/FiO2 ≤ 300 and 4 C mortality score in mortality at 28 days showed an ROC-curve of 0.624 (95% CI: 0.582-0.667) and 0.706 (95% CI: 0.669-0.742), respectively. CONCLUSION: PaO2/FiO2 ≤ 300, 4 C mortality score ≥ 8, SOFA score ≥ 4 y SaO2/FiO2 ≤ 300 were weak predictors of the IMV requirement from admission, and 4 C mortality score ≥ 8 was weak predictors of the mortality from admission in patients with pulmonary involvement by COVID-19.

The Diagnostic Accuracy of Transvaginal Ultrasound for Detection of Ureteral Involvement in Deep Infiltrating Endometriosis: A Systematic Review and Meta-Analysis.

OBJECTIVE: The aim of this study is to determine the accuracy of transvaginal ultrasound (TVU) for the diagnosis of ureteral involvement in women with deep infiltrating endometriosis (DIE). METHODS: The meta-analysis included primary studies comparing the use of TVU for diagnosing endometriotic involvement of the ureter, using laparoscopic surgery and histological diagnosis as the reference standard. Search was performed in several databases (Scopus, Web of Science, and PubMed/MEDLINE). The studies' quality and bias risk were assessed using the Quality Assessment of Diagnostic Accuracy Study-2 (QUADAS-2). Diagnostic performance was estimated by assessing pooled sensitivity and specificity. RESULTS: A total of 496 citations were found. Six articles were ultimately selected for this systematic review and meta-analysis after the inclusion and exclusion criteria were applied. Pooled sensitivity and specificity were 0.81 (95% CI: 0.42-0.96), 1.00 (95% CI: 0.93-1.00). The heterogeneity observed was high for both sensitivity and specificity. Overall risk of bias was low. CONCLUSION: TVU is a valuable tool for the pre-operative identification of ureteral involvement by DIE.

Empathy-based counterspeech can reduce racist hate speech in a social media field experiment.

Despite heightened awareness of the detrimental impact of hate speech on social media platforms on affected communities and public discourse, there is little consensus on approaches to mitigate it. While content moderation-either by governments or social media companies-can curb online hostility, such policies may suppress valuable as well as illicit speech and might disperse rather than reduce hate speech. As an alternative strategy, an increasing number of international and nongovernmental organizations (I/NGOs) are employing counterspeech to confront and reduce online hate speech. Despite their growing popularity, there is scant experimental evidence on the effectiveness and design of counterspeech strategies (in the public domain). Modeling our interventions on current I/NGO practice, we randomly assign English-speaking Twitter users who have sent messages containing xenophobic (or racist) hate speech to one of three counterspeech strategies-empathy, warning of consequences, and humor-or a control group. Our intention-to-treat analysis of 1,350 Twitter users shows that empathy-based counterspeech messages can increase the retrospective deletion of xenophobic hate speech by 0.2 SD and reduce the prospective creation of xenophobic hate speech over a 4-wk follow-up period by 0.1 SD. We find, however, no consistent effects for strategies using humor or warning of consequences. Together, these results advance our understanding of the central role of empathy in reducing exclusionary behavior and inform the design of future counterspeech interventions.

Comparative study of intracytoplasmic sperm injection using the traditional holding and the oocyte-holding pipette without aspiration.

Despite the high level of standardization of the intracytoplasmic sperm injection (ICSI) technique, there are some aspects that deserve special attention and should still be improved. The major drawback of the technique is its invasiveness, as during cytoplasmic aspiration different structures of the oocyte may be lost or damaged. This is partly because the microtools used in ICSI were not specially designed for assisted reproduction but for other medical-biological disciplines. In view of the above caveats, the aim of the study was to compare the results of ICSI with the traditional oocyte-holding pipette and the oocyte-holding pipette without aspiration (PiWA). In total, 155 patients and 1037 oocytes were included in the study. In each ICSI cycle, half of the oocytes were microinjected using a traditional holding pipette and the other half using a PiWA. In result, the PiWA technique produced a significant increase in the fertilization rate: 88.12% (95%CI: 84.62-90.92%); holding pipette: 73.33% (95%CI: 68.72-77.49%). Also, it produced a significant decrease in the embryo degeneration rate compared with the traditional holding pipette [PiWA: 2.07% (95%CI: 1.11-3.8%); holding pipette: 4.51% (95%CI: 3.06-6.59%)]. Pregnancy rate depended on the holding technique used, both in single embryo transfers (n = 59; χ2 = 4.608; P-value = 0.032) and double embryo transfers (n = 156; χ2 = 4.344; P-value = 0.037); with PiWA presenting a significantly higher pregnancy rate than the traditional holding technique. Based on current evidence and the present results, improvements should focus on decreasing the invasiveness of the microinjection itself by minimizing or avoiding aspiration and cytoplasmic disorganization, as is successfully achieved with PiWA.

A phylogenomic analysis of Limosilactobacillus reuteri reveals ancient and stable evolutionary relationships with rodents and birds and zoonotic transmission to humans.

BACKGROUND: Gut microbes play crucial roles in the development and health of their animal hosts. However, the evolutionary relationships of gut microbes with vertebrate hosts, and the consequences that arise for the ecology and lifestyle of the microbes are still insufficiently understood. Specifically, the mechanisms by which strain-level diversity evolved, the degree by which lineages remain stably associated with hosts, and how their evolutionary history influences their ecological performance remain a critical gap in our understanding of vertebrate-microbe symbiosis. RESULTS: This study presents the characterization of an extended collection of strains of Limosilactobacillus reuteri and closely related species from a wide variety of hosts by phylogenomic and comparative genomic analyses combined with colonization experiments in mice to gain insight into the long-term evolutionary relationship of a bacterial symbiont with vertebrates. The phylogenetic analysis of L. reuteri revealed early-branching lineages that primarily consist of isolates from rodents (four lineages) and birds (one lineage), while lineages dominated by strains from herbivores, humans, pigs, and primates arose more recently and were less host specific. Strains from rodent lineages, despite their phylogenetic divergence, showed tight clustering in gene-content-based analyses. These L. reuteri strains but not those ones from non-rodent lineages efficiently colonize the forestomach epithelium of germ-free mice. The findings support a long-term evolutionary relationships of L. reuteri lineages with rodents and a stable host switch to birds. Associations of L. reuteri with other host species are likely more dynamic and transient. Interestingly, human isolates of L. reuteri cluster phylogenetically closely with strains from domesticated animals, such as chickens and herbivores, suggesting zoonotic transmissions. CONCLUSIONS: Overall, this study demonstrates that the evolutionary relationship of a vertebrate gut symbiont can be stable in particular hosts over time scales that allow major adaptations and specialization, but also emphasizes the diversity of symbiont lifestyles even within a single bacterial species. For L. reuteri, symbiont lifestyles ranged from autochthonous, likely based on vertical transmission and stably aligned to rodents and birds over evolutionary time, to allochthonous possibly reliant on zoonotic transmission in humans. Such information contributes to our ability to use these microbes in microbial-based therapeutics.

Characterization of Anisotropic Salt Weathering through Nondestructive Techniques Mapping Using a GIS Environment.

Doctrinal texts on architectural heritage conservation emphasize the importance of fully understanding the structural and material characteristics and utilizing information systems. Photogrammetry allows for the generation of detailed, geo-referenced Digital Elevation Models of architectural elements at a low cost, while GIS software enables the addition of layers of material characteristic data to these models, creating different property maps that can be combined through map algebra. This paper presents the results of the mechanical characterization of materials and salt-related decay forms of the polygonal apse of the 13th-century monastery of Santa María de Bonaval (Guadalajara, Spain), which is primarily affected by salt crystallization. Rock strength is estimated using on-site nondestructive testing (ultrasound pulse velocity and Leeb hardness). They are mapped and combined through map algebra to derive a single mechanical soundness index (MSI) to determine whether the decay of the walls could be dependent on the orientation. The presented results show that salt decay in the building is anisotropic, with the south-facing side of the apse displaying an overall lower MSI than the others. The relative overheating of the south-facing side of the apse enhances the effect of salt crystallization, thereby promoting phase transitions between epsomite and hexahydrite.

"Social support and stressful life events: risk factors for antenatal depression in nulliparous and multiparous women".

Nulliparous (pregnant women who are giving birth for the first time) and multiparous (women who have multiple children) may have different concerns, which may be associated with risk of antenatal depression. This study aims to examine the role of social support and stressful life events as risk factors for antenatal depression in nulliparous and multiparous women. The sample included 1,524 pregnant women recruited from an obstetrics setting at the end of the first trimester of pregnancy from two Spanish tertiary-care public hospitals. The sample completed the Patient Health Questionnaire (PHQ-9), and the "social support" and "stressful life events" subscales of the Postpartum Depression Predictor Inventory-Revised (PDPI-R). Nulliparous women reported a lower prevalence of depressive symptoms (15.6 percent) compared to multiparous mothers (20.1 percent). In both groups, marriage/partner problems (NP: ß = 0.178, p < .01 vs MP: ß = 0.164, p < .01) and a perceived lack of instrumental support from friends (NP: ß = -0.154, p < .01 vs MP: ß = -0.154, p < .01) were significant risk factors for antenatal depression. However, nulliparous women have more risk factors such as unemployment (ß = 0.096, p < .05), job change (ß = 0.127, p < .01), financial problems (ß = 0.145, p < .01) and lack of instrumental support from partner (ß = -0187, p < .01). For multiparous women, moving (ß = 0.080, p < .05) and lack of instrumental support from family (ß = -0.151, p < .01) were risk factors. These results suggest the critical need for screening and designing preventive interventions adapted and taking into consideration parity to provide more effective health care during pregnancy.

Three-dimensional representation of the Vita Toothguide 3D-Master: An in vivo clinical study.

STATEMENT OF PROBLEM: The Vita Toothguide 3D-Master (Vita Zahnfabrik) is considered the dental shade guide in which the three dimensions of color - lightness, hue, and chroma - are most well-ordered in the CIELAB color space. No research has yet explored how well the Vita Toothguide 3D-Master is ordered in the 3D color space by recording color coordinates in vivo. PURPOSE: To evaluate the spatial color distribution of the Vita Toothguide 3D-Master's lightness, chroma, and hue groups and its 26 physical shade tabs. MATERIALS AND METHODS: The dental color (L*, C*, h°, a*, and b* color coordinates) of a healthy maxillary central incisor was recorded for 1361 participants (aged between 18 and 89 years) using a Vita Easyshade Compact spectrophotometer (Vita Zahnfabrik). The R 2.7.2. statistics program was used to create the visual representations. RESULTS: The five lightness levels are those that are best distributed in the color space, in relation to the L* coordinates, followed by the chroma group and, finally, the hue group. The 5M1, 5M2, and 5M3 physical shade tabs are situated at a greater distance apart from the other tabs in the color space. CONCLUSIONS: The Vita Toothguide 3D-Master's 26 physical shade tabs are satisfactorily distributed in three-dimensional space, although strict mathematical criteria are not followed. The natural dental shades that fall lower on the lightness scale are the most poorly represented by the physical shade tabs. CLINICAL IMPLICATIONS: Darker teeth are poorly represented by the Vita Toothguide 3D-Master's physical shade tabs. The spatial distribution of dental shade guides needs to be improved to ensure they provide homogeneous coverage of the entire chromatic spectrum corresponding to natural teeth. This would help reduce the errors inherent to the subjective visual color selection process.

Violence on social networks related to the body image of young women and its repercussions on health.

INTRODUCTION: Social networking sites perpetuate gender stereotypes, inequalities, and gender violence, generating adverse health effects. METHODS: This study aimed to analyze the relationship between Instagram, alcohol consumption and effects on health, through interviews and discussion groups involving adolescents (high school or university students and workers), during the period from the third to the sixth wave of the COVID-19 pandemic. RESULTS: A total of 118 individuals participated in the study. Three coding clusters were identified: (1) Inequality in the representation of men and women on SNSs; (2) Violence towards women's bodies and sexual violence on SNSs; and (3) Health problems derived from violence against women's body image on SNSs. The main focus of our analysis was the exhibition of the female body, in which eroticization of the body prevails and gender roles are perpetuated. Violence is generated towards women in the form of misogynistic attacks for daring to challenge conventional stereotypes. Many interviewees coincide that the main health effects include low self-esteem, anxiety and eating disorders. CONCLUSIONS: The institutional response to the abuses and violence committed on SNSs against women is weak, and public policies are needed to protect women in these environments where they are especially vulnerable.