Chitin Nanocomposites for Fused Filament Fabrication: Flexible Materials with Enhanced Interlayer Adhesion.

In this work, we present a series of nanocomposites for Fused filament fabrication (FFF) based on polycaprolactone (PCL) and chitin nanocrystals (ChNCs). The ChNCs were synthesized by acid hydrolysis using HCl or lactic acid (LA). The approach using LA, an organic acid, makes the ChNCs synthesis more sustainable and modifies their surface with lactate groups, increasing their compatibility with the PCL matrix. The ChNCs characterization by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy revealed that both ChNCs presented similar morphologies and crystallinity, while differential scanning calorimetry and thermogravimetric analysis proved that they can bear temperatures up to 210 °C without degrading, which allows their processing in the manufacturing of PCL composites by twin-screw extrusion. Therefore, PCL composites in the form of filaments containing 0.5-1.0 wt % ChNCs were produced and used as feedstock in FFF, and standard tensile and flexural specimens were printed at different temperatures, up to 170 °C, to assess the influence of the ChNCs in the mechanical properties of the material. The tensile testing results showed that the presence of ChNCs enhances the strength and ductility of the PCL matrix, increasing the elongation at break around 20-50%. Moreover, the vertically printed flexural specimens showed a very different bending behavior, such that the pure PCL specimens presented a brittle fracture at 7% strain, while the ChNCs composites were able to bend over themselves. Hence, this work proves that the presence of ChNCs aims to improve the interlayer adhesion of the objects manufactured by FFF due to their good adhesive properties, which is currently a concern for the scientific community and the industrial sector.

Relevance of the Adjuvant Effect between Cellular Homeostasis and Resistance to Antibiotics in Gram-Negative Bacteria with Pathogenic Capacity: A Study of Klebsiella pneumoniae.

Antibiotic resistance has become a global issue. The most significant risk is the acquisition of these mechanisms by pathogenic bacteria, which can have a severe clinical impact and pose a public health risk. This problem assumes that bacterial fitness is a constant phenomenon and should be approached from an evolutionary perspective to develop the most appropriate and effective strategies to contain the emergence of strains with pathogenic potential. Resistance mechanisms can be understood as adaptive processes to stressful conditions. This review examines the relevance of homeostatic regulatory mechanisms in antimicrobial resistance mechanisms. We focus on the interactions in the cellular physiology of pathogenic bacteria, particularly Gram-negative bacteria, and specifically Klebsiella pneumoniae. From a clinical research perspective, understanding these interactions is crucial for comprehensively understanding the phenomenon of resistance and developing more effective drugs and treatments to limit or attenuate bacterial sepsis, since the most conserved adjuvant phenomena in bacterial physiology has turned out to be more optimized and, therefore, more susceptible to alterations due to pharmacological action.

Differences urban versus non-urban trends in mortality from ischemic heart disease and diabetes in Italy and Spain, 2003-2019.

BACKGROUND AND AIMS: In recent years, mortality from ischemic heart disease and diabetes has decreased. There is an inequality in mortality reduction between urban and non-urban areas. This study aims to estimate the trend in mortality from ischemic heart disease and diabetes mellitus in urban and non-urban areas in Italy and Spain, throughout the first two decades of the 21st century. METHODS: Deaths and population data by age and sex, according to the area de residence, were obtained from the National Institutes of Statistics. Annual age-standardized mortality rates from ischemic heart disease and diabetes mellitus were calculated from 2003 to 2019, in each of the two areas of residence in both countries. The average annual percentage change (APC) in the mortality rate in each area was estimated using linear regression models and taking age-standardized mortality rates as dependent variable. RESULTS: Mortality rates from both causes of death decreased between the beginning and the end of the period analysed. In Italy, the APC in was -4.0% and -3.6% in mortality rate from ischemic heart disease and -1.5% and -1.3% in mortality rate from diabetes mellitus, in urban and non-urban areas, respectively. In Spain, the APC in was -4.4% and -3.7% in mortality rate from ischemic heart disease and -3.3% and -2.0% in mortality rate from diabetes mellitus, in urban and non-urban areas, respectively. CONCLUSION: Mortality from ischemic heart disease and mortality from diabetes have shown a greater reduction in urban than in non-urban areas since the first years of the 21st century in Spain and Italy.

This study evaluated the trend in mortality from ischemic heart disease and diabetes in urban and non-urban areas in two Southern European countries, Italy and Spain, throughout the first two decades of the 21st century.A reduction in mortality from diabetes and ischemic heart disease was observed in both urban and non-urban areas in both countries.Residents in urban areas showed a greater reduction in mortality than residents in non-urban areas. The mortality advantage found in non-urban areas at the beginning of the study disappeared at the end of it or even mortality became higher in non-urban areas.

Optical coherence tomography features in vitreoretinal lymphoma compared with non-infectious uveitis.

BACKGROUND: Vitreoretinal lymphoma (VRL) is a rare intraocular malignancy that poses a diagnostic challenge due to the non-specific clinical presentation that resembles uveitis. The use of spectral domain optical coherence tomography (SD-OCT) has emerged as a valuable imaging tool to characterize VRL. Therefore, we sought to determine the specific OCT features in VRL compared to the uveitides. METHODS: Retrospective chart review of patients who were seen at Mayo Clinic from January 1, 2010 through December 31, 2022. The medical records and SD-OCT images at time of initial presentation were reviewed in patients with biopsy-proven VRL, intermediate uveitis, or biopsy-confirmed sarcoid posterior uveitis. Patients with VRL or similar uveitides including intermediate uveitis or sarcoid posterior uveitis were included. RESULTS: There were 95 eyes of 56 patients in the VRL group and 86 eyes of 45 patients in the uveitis group, of whom 15 (33.3%) were diagnosed with intermediate uveitis and 30 (66.7%) with sarcoid chorioretinitis. The SD-OCT features more commonly seen at initial presentation in VRL patients (vs. uveitis) included preretinal deposits (31.6% vs. 9.3%, p = 0.002), intraretinal infiltrates (34% vs. 3.5%, p < 0.001), inner retinal hyperreflective spots (15.8% vs. 0%, p < 0.001), outer retinal atrophy (22.1% vs. 2.3%, p < 0.001), subretinal focal deposits (21.1% vs. 4.7%, p = 0.001), retinal pigmented epithelium (RPE) changes (49.5% vs. 3.5%, p < 0.001), and sub-RPE deposits (34.7% vs. 0%, p < 0.001). Features more frequently seen in uveitis included epiretinal membrane (ERM) (82.6% vs. 44.2%, p < 0.001), central macular thickening (95.3% vs. 51.6%, p < 0.001), cystoid macular edema (36% vs. 11.7%, p < 0.001), subretinal fluid (16.3% vs 6.4%, p = 0.04), and subfoveal fluid (16.3% vs. 3.2%, p = 0.003). Multivariate regression analysis controlling for age and sex showed absence of ERM (OR 0.14 [0.04,0.41], p < 0.001) and absence of central macular thickening (OR 0.03 [0,0.15], p = 0.02) were associated with VRL as opposed to uveitis. CONCLUSION: OCT features most predictive of VRL (vs. uveitis) included absence of ERM and central macular thickening.

Retinal Dystrophies Associated With Peripherin-2: Genetic Spectrum and Novel Clinical Observations in 241 Patients.

Purpose: To describe the clinical, electrophysiological and genetic spectrum of inherited retinal diseases associated with variants in the PRPH2 gene. Methods: A total of 241 patients from 168 families across 15 sites in 9 countries with pathogenic or likely pathogenic variants in PRPH2 were included. Records were reviewed for age at symptom onset, visual acuity, full-field ERG, fundus colour photography, fundus autofluorescence (FAF), and SD-OCT. Images were graded into six phenotypes. Statistical analyses were performed to determine genotype-phenotype correlations. Results: The median age at symptom onset was 40 years (range, 4-78 years). FAF phenotypes included normal (5%), butterfly pattern dystrophy, or vitelliform macular dystrophy (11%), central areolar choroidal dystrophy (28%), pseudo-Stargardt pattern dystrophy (41%), and retinitis pigmentosa (25%). Symptom onset was earlier in retinitis pigmentosa as compared with pseudo-Stargardt pattern dystrophy (34 vs 44 years; P = 0.004). The median visual acuity was 0.18 logMAR (interquartile range, 0-0.54 logMAR) and 0.18 logMAR (interquartile range 0-0.42 logMAR) in the right and left eyes, respectively. ERG showed a significantly reduced amplitude across all components (P < 0.001) and a peak time delay in the light-adapted 30-Hz flicker and single-flash b-wave (P < 0.001). Twenty-two variants were novel. The central areolar choroidal dystrophy phenotype was associated with 13 missense variants. The remaining variants showed marked phenotypic variability. Conclusions: We described six distinct FAF phenotypes associated with variants in the PRPH2 gene. One FAF phenotype may have multiple ERG phenotypes, demonstrating a discordance between structure and function. Given the vast spectrum of PRPH2 disease our findings are useful for future clinical trials.

Exploring the Associated Genetic Causes of Diabetic Retinopathy as a Model of Inflammation in Retinal Diseases.

To investigate potential biomarkers and biological processes associated with diabetic retinopathy (DR) using transcriptomic and proteomic data. The OmicsPred PheWAS application was interrogated to identify genes and proteins associated with DR and diabetes mellitus (DM) at a false discovery rate (FDR)-adjusted p-value of <0.05 and also <0.005. Gene Ontology PANTHER analysis and STRING database analysis were conducted to explore the biological processes and protein interactions related to the identified biomarkers. The interrogation identified 49 genes and 22 proteins associated with DR and/or DM; these were divided into those uniquely associated with diabetic retinopathy, uniquely associated with diabetes mellitus, and the ones seen in both conditions. The Gene Ontology PANTHER and STRING database analyses highlighted associations of several genes and proteins associated with diabetic retinopathy with adaptive immune response, valyl-TRNA aminoacylation, complement activation, and immune system processes. Our analyses highlight potential transcriptomic and proteomic biomarkers for DR and emphasize the association of known aspects of immune response, the complement system, advanced glycosylation end-product formation, and specific receptor and mitochondrial function with DR pathophysiology. These findings may suggest pathways for future research into novel diagnostic and therapeutic strategies for DR.

Predictive health monitoring: Leveraging artificial intelligence for early detection of infectious diseases in nursing home residents through discontinuous vital signs analysis.

This research addresses the problem of detecting acute respiratory, urinary tract, and other infectious diseases in elderly nursing home residents using machine learning algorithms. The study analyzes data extracted from multiple vital signs and other contextual information for diagnostic purposes. The daily data collection process encounters sampling constraints due to weekends, holidays, shift changes, staff turnover, and equipment breakdowns, resulting in numerous nulls, repeated readings, outliers, and meaningless values. The short time series generated also pose a challenge to analysis, preventing the extraction of seasonal information or consistent trends. Blind data collection results in most of the data coming from periods when residents are healthy, resulting in excessively imbalanced data. This study proposes a data cleaning process and then builds a mechanism that reproduces the basal activity of the residents to improve the classification of the disease. The results show that the proposed basal module-assisted machine learning techniques allow anticipating diagnostics 2, 3 or 4 days before doctors decide to start treatment with antibiotics, achieving a performance measured by the area-under-the-curve metric of 0.857. The contributions of this work are: (1) a new data cleaning process; (2) the analysis of contextual information to improve data quality; (3) the generation of a baseline measure for relative comparison; and (4) the use of either binary (disease/no disease) or multiclass classification, differentiating among types of infections and showing the advantages of multiclass versus binary classification. From a medical point of view, the anticipated detection of infectious diseases in institutionalized individuals is brand new.

Histological Findings in the Eyes of Abcc6 Knockout Rat Model of Pseudoxanthoma Elasticum.

Purpose: To describe the ocular findings of murine pseudoxanthoma elasticum (PXE) models with ATP-binding cassette subfamily C member 6 (Abcc6) gene knockout. Methods: This experiment was conducted in four Abcc6-/- rats and compared with six wild-type Abcc6+/+ control rats. The animals underwent necropsy at 6 months of age. Histological examination of the eyes was performed. Results: Histological examination of eight eyes from four Abcc6-/- rats revealed multiple nodular foci of calcification in the uvea, sclera, and conjunctiva, focally in perivascular distribution, as well as linear and nodular calcification of Bruch's membrane. Calcific foci were not associated with inflammation in the knockout rats. There was no evidence of calcification in control eyes. Discussion: The Abcc6-/- rat model shows that PXE can affect multiple ocular tissues beyond the calcification in Bruch's membrane noted in human eyes. Nodular calcific foci probably correspond to comet lesions seen in patients with PXE. The presence of ectopic calcium without inflammation distinguishes it from inflammatory calcium deposition in atherosclerosis. Further studies are needed to determine why PXE does not cause inflammatory infiltration. Translational Relevance: The Abcc6-/- murine model may be suitable for studying ocular PXE pathophysiology and ectopic calcification and developing effective therapies.

Pseudoxanthoma elasticum-associated angioid streaks near a scleral buckle.

Purpose: We report a patient with pseudoxanthoma elasticum (PXE) with angioid streaks near a scleral buckle site. Observations: A 46-year-old male with PXE presented for evaluation of blurry vision and was found to have classic PXE findings in both eyes and angioid streaks adjacent to the site of a scleral buckle in his left eye. He underwent multimodal imaging, genetic testing, and intravitreal aflibercept in the right eye. Conclusions and importance: Bruch's membrane is known to be fragile in PXE, and patients are often counseled about the heightened risk of playing contact sports. This report raises the question of whether tension from a scleral buckle in the setting of a calcified and brittle BM may increase the likelihood of angioid streaks near the buckle site. In the setting of retinal detachment, it may be worthwhile to carefully weigh the pros and cons of vitrectomy versus buckle for PXE patients.

New forays into measurement of ocular biomechanics.

PURPOSE OF REVIEW: The field of corneal biomechanics has rapidly progressed in recent years, reflecting technological advances and an increased understanding of the clinical significance of measuring these properties. This review will evaluate in-vivo biomechanical properties obtained by current technologies and compare them regarding their relevance to established biomechanical properties obtained by gold-standard ex-vivo techniques normally conducted on elastic materials. RECENT FINDINGS: Several new technologies have appeared in recent years, including vibrational optical coherence tomography (VOCT) and the corneal indentation device (CID). These techniques provide promising new opportunities for minimally invasive and accurate measurements of corneal viscoelastic properties. SUMMARY: Alterations in corneal biomechanics are known to occur in several corneal degenerative diseases and after refractive surgical procedures. The measurement of corneal biomechanical properties has the capability to diagnose early disease and monitor corneal disease progression. Several new technologies have emerged in recent years, allowing for more accurate and less invasive measurements of corneal biomechanical properties, most notably the elastic modulus.

Excess Mortality During 2020 in Spain: The Most Affected Population, Age, and Educational Group by the COVID-19 Pandemic.

OBJECTIVE: The objective of this work was to study mortality increase in Spain during the first and second academic semesters of 2020, coinciding with the first 2 waves of the Covid-19 pandemic; by sex, age, and education. METHODS: An observational study was carried out, using linked populations and deaths' data from 2017 to 2020. The mortality rates from all causes and leading causes other than Covid-19 during each semester of 2020, compared to the 2017-2019 averages for the same semester, was also estimated. Mortality rate ratios (MRR) and differences were used for comparison. RESULTS: All-cause mortality rates increased in 2020 compared to pre-covid, except among working-age, (25-64 years) highly-educated women. Such increases were larger in lower-educated people between the working age range, in both 2020 semesters, but not at other ages. In the elderly, the MMR in the first semester in women and men were respectively, 1.14, and 1.25 among lower-educated people, and 1.28 and 1.23 among highly-educated people. In the second semester, the MMR were 1.12 in both sexes among lower-educated people and 1.13 in women and 1.16 in men among highly-educated people. CONCLUSION: Lower-educated people within working age and highly-educated people at older ages showed the greatest increase in all-cause mortality in 2020, compared to the pre-pandemic period.

Genetic analysis of ocular tumour-associated genes using large genomic datasets: insights into selection constraints and variant representation in the population.

BACKGROUND: Large genomic databases enable genetic evaluation in terms of haploinsufficiency and prevalence of missense and synonymous variants. We explored these parameters in ocular tumour-associated genes. METHODS: A curated list of ocular tumour-associated genes was assessed using the genomic databases Genome Aggregation Database (gnomAD) and DatabasE of genomiC varIation and Phenotype in Humans using Ensembl Resources (DECIPHER) and compared with breast and lung cancer-associated gene lists. Haploinsufficiency was determined based on specific criteria: probability of loss of function index ≥0.9 in gnomAD, upper CI O/E limit <0.35 for loss of function variants in gnomAD and/or a DECIPHER pHaplo ≥0.86. UniProt was used for further gene characterisation, and gene ontology Protein Analysis THrough Evolutionary Relationships was explored for common biological pathways. In addition, we identified genes with under-representation/over-representation of missense/synonymous variants. RESULTS: Fifty-seven genes were identified in association with ocular and extraocular tumours.Regarding haploinsufficiency, 41% of genes met the criteria for negative selection, with 57% categorised as tumour-suppressing and 39% as oncogenic. Most genes were involved in regulatory processes. Regarding triplosensitivity, 33% of genes reached significance and 83% of these were haploinsufficient. Analysis of variants revealed under-representation of missense variants in 23% of genes and over-representation of synonymous variants in 5% of genes. Ocular tumour-associated genes exhibited higher scores for haploinsufficiency and triplosensitivity compared with breast and lung cancer-associated genes. Pathway analysis revealed significant enrichment in cellular proliferation, differentiation and division. Encoded proteins of ocular tumour-associated genes were generally longer than the median of the UniProt database. CONCLUSION: Our findings highlight the importance of negative selection in ocular tumour genes, supporting cranial gene conservation. This study provides insights into ocular tumourigenesis and future research avenues.

Detection of TTR Amyloid in the Conjunctiva Using a Novel Fluorescent Ocular Tracer.

Background: Transthyretin amyloidosis (ATTR) is a significant cause of cardiomyopathy and other morbidities in the elderly and Black Americans. ATTR can be treated with new disease-modifying therapies, but large shortfalls exist in its diagnosis. The objective of this study was to test whether TTR amyloid can be detected and imaged in the conjunctiva using a novel small-molecule fluorescent ocular tracer, with the implication that ATTR might be diagnosable by a simple eye examination. Methods: Three approaches were used in this study. First, AMDX-9101 was incubated with in vitro aggregated TTR protein, and changes in its excitation and emission spectra were quantified. Second, a cadaver eye from a patient with familial amyloid polyneuropathy type II TTR mutation and a vitrectomy sample from an hATTR patient were incubated with AMDX-9101 and counterstained with Congo Red and antibodies to TTR to determine whether AMDX-9101 labels disease-related TTR amyloid deposits in human conjunctiva and eye. Last, imaging of in vitro aggregated TTR amyloid labeled with AMDX-9101 was tested in a porcine ex vivo model, using a widely available clinical ophthalmic imaging device. Results: AMDX-9101 hyper-fluoresced in the presence of TTR amyloid in vitro, labeled TTR amyloid deposits in postmortem human conjunctiva and other ocular tissues and could be detected under the conjunctiva of a porcine eye using commercially available ophthalmic imaging equipment. Conclusions: AMDX-9101 enabled detection of TTR amyloid in the conjunctiva, and the fluorescent binding signal can be visualized using commercially available ophthalmic imaging equipment. Translational Relevance: AMDX-9101 detection of TTR amyloid may provide a potential new and noninvasive test for ATTR that could lead to earlier ATTR diagnosis, as well as facilitate development of new therapeutics.

Challenging the Limits of Binarization: A New Scheme Selection Policy Using Reinforcement Learning Techniques for Binary Combinatorial Problem Solving.

In this study, we introduce an innovative policy in the field of reinforcement learning, specifically designed as an action selection mechanism, and applied herein as a selector for binarization schemes. These schemes enable continuous metaheuristics to be applied to binary problems, thereby paving new paths in combinatorial optimization. To evaluate its efficacy, we implemented this policy within our BSS framework, which integrates a variety of reinforcement learning and metaheuristic techniques. Upon resolving 45 instances of the Set Covering Problem, our results demonstrate that reinforcement learning can play a crucial role in enhancing the binarization techniques employed. This policy not only significantly outperformed traditional methods in terms of precision and efficiency, but also proved to be extensible and adaptable to other techniques and similar problems. The approach proposed in this article is capable of significantly surpassing traditional methods in precision and efficiency, which could have important implications for a wide range of real-world applications. This study underscores the philosophy behind our approach: utilizing reinforcement learning not as an end in itself, but as a powerful tool for solving binary combinatorial problems, emphasizing its practical applicability and potential to transform the way we address complex challenges across various fields.

Reliability and accuracy of artificial intelligence ChatGPT in providing information on ophthalmic diseases and management to patients.

PURPOSE: To assess the accuracy of ophthalmic information provided by an artificial intelligence chatbot (ChatGPT). METHODS: Five diseases from 8 subspecialties of Ophthalmology were assessed by ChatGPT version 3.5. Three questions were asked to ChatGPT for each disease: what is x?; how is x diagnosed?; how is x treated? (x = name of the disease). Responses were graded by comparing them to the American Academy of Ophthalmology (AAO) guidelines for patients, with scores ranging from -3 (unvalidated and potentially harmful to a patient's health or well-being if they pursue such a suggestion) to 2 (correct and complete). MAIN OUTCOMES: Accuracy of responses from ChatGPT in response to prompts related to ophthalmic health information in the form of scores on a scale from -3 to 2. RESULTS: Of the 120 questions, 93 (77.5%) scored ≥ 1. 27. (22.5%) scored ≤ -1; among these, 9 (7.5%) obtained a score of -3. The overall median score amongst all subspecialties was 2 for the question "What is x", 1.5 for "How is x diagnosed", and 1 for "How is x treated", though this did not achieve significance by Kruskal-Wallis testing. CONCLUSIONS: Despite the positive scores, ChatGPT on its own still provides incomplete, incorrect, and potentially harmful information about common ophthalmic conditions, defined as the recommendation of invasive procedures or other interventions with potential for adverse sequelae which are not supported by the AAO for the disease in question. ChatGPT may be a valuable adjunct to patient education, but currently, it is not sufficient without concomitant human medical supervision.

Osteogenic organoid for bone regeneration: Healing of bone defect in congenital pseudoarthrosis of the tibia.

BACKGROUND: Congenital pseudoarthrosis of the tibia (CPT) is an uncommon disease associated with failure to achieve bone union and recurrent fractures. There is evidence showing that CPT is associated with decreased osteogenesis. Based on the capacity of mesenchymal stromal cells (MSCs) to induce osteogenesis, we develop an osteogenic organoid (OstO) constituted by these cells, and other components of the bone niche, for inducing bone formation in a child diagnosed with CPT. AIM: To evaluate the capacity of an OstO to induce bone formation in a patient with CPT. METHODS: The OstO was fabricated with allogeneic bone marrow MSCs from a healthy donor, collagen microbeads (CM) and PRP clot. The CM and PRP function as extracellular matrix and scaffolds for MSC. The OstO was placed at the site of non-union. Internal and external fixation was placed in the tibia. Radiological evaluation was performed after MSCs transplantation. RESULTS: After 4 months of MSCs transplantation, radiographic imaging showed evidence of osteogenesis at the site of CPT lesion. The tibia showed bone consolidation and complete healing of the non-union CPT lesion after 6 months. Functional improvement was observed after 1 year of MSC transplantation. CONCLUSIONS: The OstO is a bone-like niche which promote osteogenesis in patients with failure in bone formation, such as CPT. To our knowledge, these results provide the first evidence showing CPT healing induced by an OstO constituted by allogeneic MSCs. Future studies incorporating a larger number of patients may confirm these results.

[Daily use of HIV pre-exposure prophylaxis among gay, bisexual and other men who have sex with men in Spain: Prevalence and associated factors]. / El uso diario de la profilaxis preexposición para el VIH en hombres gais, bisexuales y otros hombres que tienen sexo con hombres en España: prevalencia y factores asociados.

OBJECTIVE: We aim to estimate the prevalence of daily HIV pre-exposure prophylaxis (PrEP) use 6 months after public funding approval in Spain and identify associated factors in a national sample of gay, bisexual and other men who have sex with men (GBMSM). MATERIAL AND METHODS: We analysed 4692 HIV-undiagnosed GBMSM men recruited via an online questionnaire distributed nationally via gay contact apps and websites between May and July 2020. We estimated the proportion of participants using daily PrEP and identified associated factors using Poisson regression with robust variance. RESULTS: Daily PrEP use was reported by 2.8% (95% CI 2.3-3.3) of all participants. Daily PrEP use was independently associated with being recruited into community programmes, being older than 30 years, living in a large city, living with men, having condomless anal intercourse with more than 10 sexual partners, using drugs for sex, especially chemsex drugs, and being diagnosed with a sexually transmitted infection. CONCLUSION: Six months after PrEP was approved in Spain, the prevalence of daily use is low in a national sample of GBMSM men. There is a need to promote access, demand and interest in PrEP, especially among young GBMSM men, those living in small and medium-sized cities, and those who hide their relationships with other men.

Heavy Drinking by Occupation in Spain: Differences Between Weekdays and the Weekend.

Estimating occupational disparity in heavy drinking jointly for weekdays and the weekend may be misleading for prevention purposes, because reasons for disparity in both periods may differ. The main objective was to assess occupational disparity in heavy average drinking (HAD) by week period and sex. 42,108 employees aged 16-64 were recruited from national surveys in Spain between 2011 and 2020. The outcome was HAD, defined as daily alcohol intake over 20 g (men) or 10 g (women). Occupation was classified in 15 categories. HAD adjusted prevalence ratios (HAD-aPRs) taking all occupations as reference, and relative adjusted excess prevalences (HAD-aEPs) comparing the weekend to weekdays in each occupation, were estimated using Poisson regression models with robust variance adjusted for sociodemographic and health covariates. The HAD-aPRs comparing each occupation with all occupations ranged 0.63-1.92 on weekdays and 0.65-1.45 on the weekend, with the highest aPRs on weekdays in construction, hospitality and primary-sector workers (1.92-1.62). The weekend-weekdays HAD-aEPs by occupation ranged 2.60-8.33, with the highest values in technicians/administrators, other professionals, teachers and health professionals (8.33-6.44). The global aEP was higher in women (6.04) than in men (3.92), especially in occupations just mentioned (8.70-11.73 in women vs. 3.64-6.32 in men). There was a considerable relative disparity in HAD risk between occupations on weekdays, with the highest risks in certain low-skilled occupations. Such disparity decreased on the weekend. The relative weekend increase in HAD risk was greater in women and in certain high-skilled occupations. This should be considered when designing prevention interventions on harmful drinking.