RAD51 restricts DNA over-replication from re-activated origins

Eukaryotic cells rely on several mechanisms to ensure that the genome is duplicated precisely once in each cell division cycle, preventing DNA over-replication and genomic instability. Most of these mechanisms limit the activity of origin licensing proteins to prevent the reactivation of origins that have already been used. Here, we have investigated whether additional controls restrict the extension of re-replicated DNA in the event of origin re-activation. In a genetic screening in cells forced to re-activate origins, we found that re-replication is limited by RAD51 and enhanced by FBH1, a RAD51 antagonist. In the presence of chromatin-bound RAD51, forks stemming from re-fired origins are slowed down, leading to frequent events of fork reversal. Eventual re-initiation of DNA synthesis mediated by PRIMPOL creates ssDNA gaps that facilitate the partial elimination of re-duplicated DNA by MRE11 exonuclease. In the absence of RAD51, these controls are abrogated and re-replication forks progress much longer than in normal conditions. Our study uncovers a safeguard mechanism to protect genome stability in the event of origin reactivation.

Treatment of infantile-onset Pompe disease in a rat model with muscle-directed AAV gene therapy

OBJECTIVE

Pompe disease (PD) is caused by deficiency of the lysosomal enzyme acid α-glucosidase (GAA), leading to progressive glycogen accumulation and severe myopathy with progressive muscle weakness. In the Infantile-Onset PD (IOPD), death generally occurs <1 year of age. There is no cure for IOPD. Mouse models of PD do not completely reproduce human IOPD severity. Our main objective was to generate the first IOPD rat model to assess an innovative muscle-directed adeno-associated viral (AAV) vector-mediated gene therapy.

METHODS

PD rats were generated by CRISPR/Cas9 technology. The novel highly myotropic bioengineered capsid AAVMYO3 and an optimized muscle-specific promoter in conjunction with a transcriptional cis-regulatory element were used to achieve robust Gaa expression in the entire muscular system. Several metabolic, molecular, histopathological, and functional parameters were measured.

RESULTS

PD rats showed early-onset widespread glycogen accumulation, hepato- and cardiomegaly, decreased body and tissue weight, severe impaired muscle function and decreased survival, closely resembling human IOPD. Treatment with AAVMYO3-Gaa vectors resulted in widespread expression of Gaa in muscle throughout the body, normalizing glycogen storage pathology, restoring muscle mass and strength, counteracting cardiomegaly and normalizing survival rate.

CONCLUSIONS

This gene therapy holds great potential to treat glycogen metabolism alterations in IOPD. Moreover, the AAV-mediated approach may be exploited for other inherited muscle diseases, which also are limited by the inefficient widespread delivery of therapeutic transgenes throughout the muscular system.

SIN3A histone deacetylase action counteracts MUS81 to promote stalled fork stability

During genome duplication, replication forks (RFs) can be stalled by different obstacles or by depletion of replication factors or nucleotides. A limited number of histone post-translational modifications at stalled RFs are involved in RF protection and restart. Provided the recent observation that the SIN3A histone deacetylase complex reduces transcription-replication conflicts, we explore the role of the SIN3A complex in protecting RFs under stressed conditions. We observe that Sin3A protein is enriched at replicating DNA in the presence of hydroxyurea. In this situation, Sin3A-depleted cells show increased RF stalling, H3 acetylation, and DNA breaks at stalled RFs. Under Sin3A depletion, RF recovery is impaired, and DNA damage accumulates. Importantly, these effects are partially dependent on the MUS81 endonuclease, which promotes DNA breaks and MRE11-dependent DNA degradation of such breaks. We propose that chromatin deacetylation triggered by the SIN3A complex limits MUS81 cleavage of stalled RFs, promoting genome stability when DNA replication is challenged.

Oxidative damage associated with exposure to heavy metals present in topsoils in central Chile

Exposure to heavy metals may cause the overproduction of reactive oxygen species, generating oxidative stress and consequently, various harms to human health. The soil surrounding the Ventanas Industrial Complex, in Puchuncaví and Quintero municipal districts on the central Chilean coast, contains heavy metal concentrations (As, Cu, Pb, Zn, among others) that far exceed the maximum permissible levels established by Italian soil standards (used as a reference). This study aimed to investigate the potential association between heavy metal exposure in humans and the levels of oxidative stress biomarkers in inhabitants of these locations. We took blood samples from 140 adults living in sites with high concentrations of heavy metals in the soil and compared them with blood samples from 140 adults living in areas with normal heavy metal concentrations. We assessed lipid peroxidation, damage to genetic material, and Total Antioxidant Capacity in these blood samples. Our results indicate an association between oxidative damage and heavy metal exposure, where the inhabitants living in exposed areas have a higher level of DNA damage compared with those living in control areas. Given that DNA damage is one of the main factors in carcinogenesis, these results are of interest, both for public health and for public policies aimed at limiting human exposure to environmental pollution.

Trends in mortality from cardiovascular diseases in Chile, 2000-2020

Objective

To analyze trends in mortality caused by cardiovascular diseases (CVD) in Chile during the period 2000-2020.

Methods

Data on age-adjusted mortality rates (AAMR) from CVD per 100 000 population in Chile for 2000-2020 were extracted from the World Health Organization Mortality Database. Joinpoint regression was used to analyze the trends and compute the average annual percent change (AAPC) in Chile. In addition, analyses were conducted by sex and type of CVD.

Results

Between 2000 and 2020, the AAMR from CVD decreased in Chile from 159.5 to 94.6 per 100 000 population, with a statistically significant decrease in the AAPC of 2.6% (95% CI [-2.8, -2.4]). No joinpoints were identified. The AAMR from CVD decreased annually by 2.6% (95% CI [-2.8, -2.4]) and 2.8% (95% CI [-3.5, -2.6]) in men and women, respectively. The AAMR from ischemic heart disease reduced annually by 3.6% (95% CI [-4.6, -2.7]) with two joinpoints in 2011 and 2015. In the case of stroke, the mortality rate decreased annually by 3.7% (95% CI [-4.5, -3.0]), with two joinpoints in 2008 and 2011.

Conclusions

Cardiovascular disease mortality rates have decreased significantly in Chile, in both sexes, especially in women. This decrease could be explained mainly by a significant reduction in the case fatality in recent decades. These results could be a reference for developing primary prevention and acute management of CVD policies focused on populations with higher mortality.

Validity and reliability of the international physical activity questionnaire short form in Chilean adults

PURPOSE

This study aimed to determine the test-retest reliability and concurrent validity of the International Physical Activity Questionnaire Short Form (IPAQ-SF) in Chilean adults.

METHODS

A cross-sectional validation study was carried out on 161 adults aged between 35 and 65, selected from a population-based study in Temuco, Chile. IPAQ-SF was completed twice, seven days apart, to analyze the test-retest reliability with the intraclass correlation coefficient (ICC). Objective PA was assessed by accelerometry (ActiGraph GT3X+) for seven consecutive days. Intraclass correlation coefficients were used to determine the reliability. Spearman correlation coefficients (rho) and Bland-Altman plots were calculated to assess validity.

RESULTS

144 subjects (52.5 ± 8.8 years, 53.9% men) answered the IPAQ-SF on both occasions and had valid accelerometry data. The IPAQ-SF showed moderate reliability for sitting time (ICC = 0.62), while it was poor for walking (ICC = 0.40), moderate PA (ICC = 0.41), vigorous PA (ICC = 0.48), and total PA (ICC = 0.33). There were weak correlations between IPAQ-SF and accelerometry for sedentary behavior (rho = 0.28, p = 0.0005), walking (rho = 0.11, p = 0.17), moderate PA (rho = 0.13, p = 0.128), vigorous PA (rho = 0.18, p = 0.03), and total PA (rho = 0.26, p = 0.002).

CONCLUSIONS

The results suggest that the IPAQ-SF test and retest would provide an acceptable measure of total SB and MVPA, and a weak correlation between IPAQ-SF and accelerometer.

Regional Disparities in Prevalence and Causes of Visual Impairment and Blindness, Cataract Surgical Coverage and Ocular Findings in Adults 50 Years and Older in Brazil: A Comparative Analysis between Two Population-Based Cross-Sectional Surveys Performed Within a 10-Year Interval

PURPOSE

To investigate disparities in the prevalence and causes of visual impairment and blindness, cataract surgical coverage, and ocular findings in older adults from two Brazilian geo-socio-demographic areas, São Paulo and Parintins cities.

METHODS

Data from two population-based studies including participants 50 years and older from the cities of São Paulo (São Paulo Eye Study - SPES, 2004) and Parintins (Brazilian Amazon Region Eye Survey - BARES, 2014) were aggregated.

RESULTS

A total of 5318 participants (3677 from SPES;1641 from BARES) were included. The prevalence of severe visual impairment (SVI) and blindness were, respectively, 0.74% (0.46-1.02) and 0.77% (0.48-1.05) in SPES and 1.72% (1.09-2.35) and 3.44% (2.55-4.33) in BARES. SVI and blindness were associated with BARES study [OR = 2.27 (1.30-3.95); p = .004 - SVI] [OR:4.07 (2.51-6.60); p < .001- blindness]; and older age [OR = 10.93 (4.20-28.45); p < .001 - SPES; OR = 17.96 (8.75-36.83); p < .001 - BARES] while higher education level was a protective factor [OR = 0.21 (0.05-0.95) - SPES; p = .042; OR = 0.21 (0.05-0.91); p = .037 - BARES]. Cataract was the main cause of bilateral severe visual impairment (25.93% in SPES and 64.29% in BARES) and bilateral blindness (21.43% in SPES and 35.71% in BARES). Cataract surgical coverage was significantly lower in BARES (36.32%) compared to SPES (57.75%).

CONCLUSION

The prevalence of SVI and blindness was three times higher in older adults from the Brazilian Amazon compared to those living in São Paulo city, despite a 10-year interval between the two studies. These disparities should be mitigated by initiatives to promote access to eye care services targeting underprivileged and remote Brazilian areas.

Intergenerational sex and early sexual debut are associated with HIV infection among transgender women in Paraguay

INTRODUCTION

HIV prevalence among transgender women is high worldwide. The objectives of the present study were to estimate the current prevalence of HIV and identify factors associated with high HIV burden among transgender women in Paraguay.

METHODS

Transgender women aged ≥15 years in four regions of Paraguay were recruited by Starfish sampling between February and March 2021.

RESULTS

In total, 322 transgender women were included. Mean age was 31 years (range 15-67), and 102 had positive HIV test results (31.7%, 95% confidence interval [CI] 26.6-37.1). In multivariable analysis, factors associated with HIV infection were age at first intercourse ≤17 years (adjusted odds ratio [aOR] 5.47; 95% CI 1.05-28.42), >10 years difference in age with the last sexual partner (aOR 1.60; 95% CI 1.04-2.46), substance use (mostly cocaine) (aOR 3.00; 95% CI 1.47-6.12), higher risk perception (aOR 3.08; 95% CI 1.53-6.17), not testing for HIV (aOR 1.23; 95% CI 1.09-1.39), and accessed by a peer educator (aOR 3.86; 95% CI 1.77-8.38).

CONCLUSIONS

Sexual debut as a minor and a large age difference with sexual partners are associated with high burden of HIV among transgender women in Paraguay. Our study corroborates the finding of cocaine use during sex as a risk factor for HIV. Prevention programmes must address structural and social vulnerabilities to stem the tragically high burden of HIV among transgender women.

Association of screen time and physical activity with health-related quality of life in college students

OBJECTIVE

To determine the association between screen time and physical activity with quality of life among Chilean university students.

METHODS

Cross-sectional and analytical study conducted on 726 first-year university students who replied three questionnaires: Youth Risk Behavior Survey, WHO Quality of Life-BREF scale, and the International Physical Activity Questionnaire.

RESULTS

There were differences in overall quality of life (p < .001) and level of satisfaction in health (p < .01) according to screen exposure time. These results follow a linear trend for all the quality of life domains (p < .01), and they indicate that there is an inverse association between screen time and quality of life.

CONCLUSION

There is an inverse association between screen time and quality of life in university students. Students with a longer screen exposure time showed a lower quality of life, specifically in the domains of social relationships and psychological health, regardless of sex, physical activity, or socioeconomic level.

Integrated gene expression profiles reveal a transcriptomic network underlying the thermogenic response in adipose tissue

Obesity and type 2 diabetes are two closely related diseases representing a serious threat worldwide. An increase in metabolic rate through enhancement of non-shivering thermogenesis in adipose tissue may represent a potential therapeutic strategy. Nevertheless, a better understanding of thermogenesis transcriptional regulation is needed to allow the development of new effective treatments. Here, we aimed to characterize the specific transcriptomic response of white and brown adipose tissues after thermogenic induction. Using cold exposure to induce thermogenesis in mice, we identified mRNAs and miRNAs that were differentially expressed in several adipose depots. In addition, integration of transcriptomic data in regulatory networks of miRNAs and transcription factors allowed the identification of key nodes likely controlling metabolism and immune response. Moreover, we identified the putative role of the transcription factor PU.1 in the regulation of PPARγ-mediated thermogenic response of subcutaneous white adipose tissue. Therefore, the present study provides new insights into the molecular mechanisms that regulate non-shivering thermogenesis.

Impact of pterygium on central corneal thickness measured by optical coherence tomography in older adults

PURPOSE

To measure the central corneal thickness (CCT) using anterior segment optical coherence tomography (AS-OCT) in older adults with and without pterygium from the Brazilian Amazon Region Eye Survey (BARES).

METHODS

BARES is a population-based epidemiological cross-sectional study conducted in Parintins city. Participants were residents ≥45 years of age identified through a door-to-door interview. Eligible participants were invited for a comprehensive eye exam. Pterygium occurrence and severity were assessed by ophthalmologists through slit-lamp examination considering its location (nasal or/and temporal) and severity (lesion with extension <3 mm, ≥3 mm not reaching the pupillary margin or ≥3 mm reaching the pupillary margin). CCTs were obtained and measurements from the more severely affected eye were included. Images were analyzed offline by masked observers.

RESULTS

A total of 671 subjects, 533 (79.4%) with pterygium in at least one eye and 138 (20.6%) without pterygium in either eye, were examined. The mean CCT evaluated by multiple linear regression and adjusted for demographic variables and pterygium severity was 521 ± 34 μm (median = 521; range = 304-665). Decreased CCT was significantly associated with age and pterygium severity. Individuals aged 65-74 years had CCT 7 μm thinner than those aged 45-54 years (p = 0.044), individuals aged 75 years and older had CCT 15 μm thinner than those aged 45-54 years (p = 0.001), and eyes with severe pterygium had CCT 33 μm thinner than eyes without pterygium (p < 0.001).

CONCLUSIONS

The CCT analysis in this population-based sample shows that a thinner cornea is associated with pterygium severity and older age.

Barriers of Access to Opioid Medicines within the Context of Palliative Care in Latin America: The Perception of Health Professionals

Background: Different sets of barriers have been identified to explain the difficulties in the access and availability of opioid analgesics in palliative care, particularly in low- and middle-income countries, including Latin America. Objective: To validate a structured questionnaire for the access to opioid medicines and to investigate the perception of health professionals regarding access barriers to opioid analgesics in 17 countries of the Latin American Region. Design: Survey to identify the domains and barriers of access to opioid medicines according to health professionals, including physicians, nurses, and pharmacists affiliated to institutions that provide palliative care in Latin America between August 2019 and October 2020. Results: We analyzed responses from 426 health professionals. The median age was 44 years old (ranging from 23 to 73 years) with an average experience in palliative care of 10 years (range: 1-35), 71.8% were women, and 49.8% were affiliated to specialized health care facilities of urban areas (94.6%). The main barriers perceived to be extremely relevant by the respondents were "belief that patients can develop addiction" and "financial limitations of patients" for the patient's domain and the "appropriate education, instruction, and training of professionals" for health professional's domain. Conclusions: It is necessary to develop strategies to strengthen less-developed health systems of the region to review legal frameworks, ensure integrated palliative care systems, and deploy multidisciplinary strategies for sensitizing, training, and raising the awareness of patients, caregivers and, particularly, health professionals regarding appropriate prescription and rational use of opioid analgesics.

Structural validity and reliability of the "Oral Health Assessment Tool" applied by speech-language therapists in a population of older Chilean people

BACKGROUND

A good state of oral health allows people to communicate and eat. This topic is relevant in older people given its close relationship with their general health. At present, health challenges are directed at detecting and preventing oral disorders and are seen to exclusively by dentists, because the existing instruments can only be applied by them. However, speech-language therapists undergo similar training, which would allow them to collaborate in these processes. In this context, the Oral Health Assessment Tool (OHAT) is a detection instrument with good psychometric properties that is currently available for non-dental use. The objective of this study is the translation into Chilean Spanish of the OHAT and a structural validation of that version for application by these professionals.

MATERIALS AND METHODS

A mixed qualitative-quantitative study was carried out. The OHAT instrument was adapted to Chilean Spanish and subsequently subject to structural validity and evaluation of internal consistency reliability, as well as a valuation of its reproducibility in 286 older people (166 female, 120 male) from different health contexts.

RESULTS

The cultural adaptation of the instrument proved to be semantically consistent with the original instrument. Its application was considered to be speedy and simple in the pre-test. The confirmatory factor analysis evidenced the unidimensionality of the OHAT. In addition, the instrument shows good internal consistency and test-retest reliability.

CONCLUSIONS

The OHAT instrument was considered to possess adequate structural validity and test-retest reliability properties. Its usefulness in the context of oral health disorders of this population in Chile is discussed.

Validación de un método automatizado basado en espectrofotometría para el análisis de sulfito en vino

Si hay un aditivo al que aún es difícil renunciar en la elaboración de vinos es el sulfito. Hasta la fecha no se ha conseguido ningún producto que aglutine las cualidades antimicrobianas, antioxidantes y antioxidásicas de este compuesto. BioSystems dispone de un reactivo automatizado mediante el uso del analizador Y15, para la cuantificación de sulfito libre en vino y mosto. Se presentan los datos de la validación: el rango de linealidad es de 0 a 100 mg/l (r2>0,99). El LOQ es de 2,1 mg/l y los valores de precisión en todo el rango de medida están entre 1,0 y 1,3 % (repetibilidad) y 1,1 y 2,1 % (reproducibilidad). Las comparaciones con el método de referencia tipo II, Franz- Paul (OIV-MA-AS323-04B) realizadas en diversos laboratorios, muestran una buena correlación. El método Free Sulfite Y15 BioSystems automatizado, simple y rápido ha sido validado con éxito.

Deficiencias de cobre, hierro y zinc en niños menores de 5 años

Introducción: La determinación de niveles séricos de micronutrientes de los niños menores de 5 años, es un requerimiento básico para establecer la prevalencia de deficiencias nutricionales de la población infantil y es una estrategia útil para incentivar a Salud Pública para que tome medidas en cuanto a aplicación y/o modificación de las Políticas Alimentarias Nacionales. Objetivo: Determinar los niveles séricos de cobre, hierro y zinc en niños paraguayos menores de 5 años. Materiales y Métodos: Estudio observacional, descriptivo y de corte transversal. Se procesaron las muestras de sangre de 1.441 niños menores de 5 años de edad que provenían de los Departamentos de Alto Paraná, Caaguazú, Central y de la capital de Paraguay. Se realizaron hemogramas y se determinaron las concentraciones séricas de albúmina, cobre, ferritina y zinc, de todas las muestras. Resultados: Los niños tuvieron una edad promedio de 3 años y 3 meses, fueron 52,74% de sexo masculino y 47,26% de sexo femenino. La prevalencia de anemia fue de 45,25% y la prevalencia de hipoalbuminemia fue de 20,65%. Se detectaron deficiencias de cobre en 14,03%, de ferritina en 6,98% y de zinc en 43,62%, de los niños. Conclusión: Los resultados de este estudio avalan la necesidad de ampliar la cobertura del Programa Alimentario Nutricional Integral (PANI), de plantearse si se deben ajustar las cantidades de minerales y vitaminas de la fórmula nutricional del Programa y de mejorar el seguimiento de los controles prenatales de las madres.

A truncating variant of RAD51B associated with primary ovarian insufficiency provides insights into its meiotic and somatic functions

Primary ovarian insufficiency (POI) causes female infertility by abolishing normal ovarian function. Although its genetic etiology has been extensively investigated, most POI cases remain unexplained. Using whole-exome sequencing, we identified a homozygous variant in RAD51B -(c.92delT) in two sisters with POI. In vitro studies revealed that this variant leads to translation reinitiation at methionine 64. Here, we show that this is a pathogenic hypomorphic variant in a mouse model. Rad51bc.92delT/c.92delT mice exhibited meiotic DNA repair defects due to RAD51 and HSF2BP/BMRE1 accumulation in the chromosome axes leading to a reduction in the number of crossovers. Interestingly, the interaction of RAD51B-c.92delT with RAD51C and with its newly identified interactors RAD51 and HELQ was abrogated or diminished. Repair of mitomycin-C-induced chromosomal aberrations was impaired in RAD51B/Rad51b-c.92delT human and mouse somatic cells in vitro and in explanted mouse bone marrow cells. Accordingly, Rad51b-c.92delT variant reduced replication fork progression of patient-derived lymphoblastoid cell lines and pluripotent reprogramming efficiency of primary mouse embryonic fibroblasts. Finally, Rad51bc.92delT/c.92delT mice displayed increased incidence of pituitary gland hyperplasia. These results provide new mechanistic insights into the role of RAD51B not only in meiosis but in the maintenance of somatic genome stability.

Hepatocellular carcinoma downstaging for liver transplantation in the era of systemic combined therapy with anti-VEGF/TKI and immunotherapy

Hepatocellular carcinoma remains a global health challenge affecting close to 1 million cases yearly. Liver transplantation provides the best long-term outcomes for those meeting strict criteria. Efforts have been made to expand these criteria, whereas others have attempted downstaging approaches. Although locoregional approaches to downstaging are appealing and have demonstrated efficacy, limitations and challenges exists including poor imaging modality to assess response and appropriate endpoints along the process. Recent advances in systemic treatments including immune checkpoint inhibitors alone or in combination with tyrosine kinase inhibitors have prompted the discussion regarding their role for downstaging disease prior to transplantation. Here, we provide a review of prior locoregional approaches for downstaging, new systemic agents and their role for downstaging, and finally, key and critical considerations of the assessment, endpoints, and optimal designs in clinical trials to address this key question.

[Psychomotor development trajectories according to nutritional status in breastfed children]

OBJECTIVE

To describe psychomotor development (PMD) trajectories and nutrition in children fed with breastfeeding (BF) and to evaluate possible associations.

SUBJECTS AND METHOD

Prospective co hort of full-term infants, without known pathologies, fed with BF. The intake of BF was evaluated with an isotopic technique at three months. At six successive ages, the nutritional status was evaluated according to the body mass index (BMI) for age and the PMD using the Ages and Stages Questionnai re (ASQ-3). Children who had at least two follow-up evaluations were included. Multivariate analysis of the trajectories by the PMD domain was performed according to BMI/A and BF, controlled by bio- socio-demographic variables.

RESULTS

53 children were included (60% male), 76 % were eutrophic, and 62% and 38% were fed exclusively or predominantly with BF, respectively. The nutritional and PMD trajectories were stable and within the normal range; there were no infants in the obesity ran ge. In the multivariate analysis, the Communication domain was significantly associated with BMI (p = 0.049) and BF (p = 0.032). Problem Solving domain was associated with BMI (p = 0.040). No significant associations were found in the trajectories of motor and socio-individual domains. Con clusion: The nutritional trajectories and each PMD domains were stable and within normal ranges. Exclusive BF was associated with a better Communication trajectory, while the BMI was associated with better Communication and Problem-Solving.

Sensitivity and Specificity of Patient-Reported Clinical Manifestations to Diagnose COVID-19 in Adults from a National Database in Chile: A Cross-Sectional Study

Simple Summary

COVID-19 is frequently suspected based on clinical features, such as fever, cough, headache, or loss of taste. However, it remains unclear whether these manifestations are reliable indicators of disease. We sought to evaluate the diagnostic accuracy of clinical manifestations in identifying patients with COVID-19. Data from a nationwide database comprising of 2,187,962 patients who sought medical care in Chile were analysed. Information regarding age, gender, type of insurance, a history of a close contact with COVID-19, and several clinical features was obtained. The most common complaints were headache, muscle aches, and cough. No single clinical feature was precise enough to fully confirm or exclude COVID-19. The combination of several of these manifestations with epidemiological risk factors into a model showed a reasonable accuracy in detecting cases of COVID-19.

Abstract

(1) Background: The diagnosis of COVID-19 is frequently made on the basis of a suggestive clinical history and the detection of SARS-CoV-2 RNA in respiratory secretions. However, the diagnostic accuracy of clinical features is unknown. (2) Objective: To assess the diagnostic accuracy of patient-reported clinical manifestations to identify cases of COVID-19. (3) Methodology: Cross-sectional study using data from a national registry in Chile. Infection by SARS-CoV-2 was confirmed using RT-PCR in all cases. Anonymised information regarding demographic characteristics and clinical features were assessed using sensitivity, specificity, and diagnostic odds ratios. A multivariable logistic regression model was constructed to combine epidemiological risk factors and clinical features. (4) Results: A total of 2,187,962 observations were available for analyses. Male participants had a mean age of 43.1 ± 17.5 years. The most common complaints within the study were headache (39%), myalgia (32.7%), cough (31.6%), and sore throat (25.7%). The most sensitive features of disease were headache, myalgia, and cough, and the most specific were anosmia and dysgeusia/ageusia. A multivariable model showed a fair diagnostic accuracy, with a ROC AUC of 0.744 (95% CI 0.743–0.746). (5) Discussion: No single clinical feature was able to fully confirm or exclude an infection by SARS-CoV-2. The combination of several demographic and clinical factors had a fair diagnostic accuracy in identifying patients with the disease. This model can help clinicians tailor the probability of COVID-19 and select diagnostic tests appropriate to their setting.

Arsenic concentration in topsoil of central Chile is associated with aberrant methylation of P53 gene in human blood cells: a cross-sectional study

Gene expression can be modified in people who are chronically exposed to high concentrations of heavy metals. The soil surrounding the Ventanas Industrial Complex, located on the coastal zone of Puchuncaví and Quintero townships (Chile), contain heavy metal concentrations (As, Cu, Pb, Zn, among others) that far exceed international standards. The aim of this study was to determine the potential association of the heavy metals in soils, especially arsenic, with the status of methylation of four tumor suppressor genes in permanent residents in those townships. To study the methylation status in genes p53, p16, APC, and RASSF1A, we took blood samples from adults living in areas near the industrial complex for at least 5 years and compared it to blood samples from adults living in areas with normal heavy metal concentrations of soils. Results indicated that inhabitants of an area with high levels of heavy metals in soil have a significantly higher proportion of methylation in the promoter region of the p53 tumor suppressor gene compared with control areas (p-value: 0.0035). This is the first study to consider associations between heavy metal exposure in humans and aberrant DNA methylation in Chile. Our results suggest more research to support consistent decision-making on processes of environmental remediation or prevention of exposure.

AAV-mediated BMP7 gene therapy counteracts insulin resistance and obesity

Type 2 diabetes, insulin resistance, and obesity are strongly associated and are a major health problem worldwide. Obesity largely results from a sustained imbalance between energy intake and expenditure. Therapeutic approaches targeting metabolic rate may counteract body weight gain and insulin resistance. Bone morphogenic protein 7 (BMP7) has proven to enhance energy expenditure by inducing non-shivering thermogenesis in short-term studies in mice treated with the recombinant protein or adenoviral vectors encoding BMP7. To achieve long-term BMP7 effects, the use of adeno-associated viral (AAV) vectors would provide sustained production of the protein after a single administration. Here, we demonstrated that treatment of high-fat-diet-fed mice and ob/ob mice with liver-directed AAV-BMP7 vectors enabled a long-lasting increase in circulating levels of this factor. This rise in BMP7 concentration induced browning of white adipose tissue (WAT) and activation of brown adipose tissue, which enhanced energy expenditure, and reversed WAT hypertrophy, hepatic steatosis, and WAT and liver inflammation, ultimately resulting in normalization of body weight and insulin resistance. This study highlights the potential of AAV-BMP7-mediated gene therapy for the treatment of insulin resistance, type 2 diabetes, and obesity.

Implant site development requirements in an advanced dental education program: A series of 290 implants

PURPOSE

Our purpose was to assess the frequency and impact of various site development procedures provided before, during, and after implant placement in an advanced dental education program.

METHODS

We evaluated all implant cases completed by two residents in each of three consecutive periodontics residency classes. Dependent variables included implant failure, complication occurrence, presence of radiographic bone loss, and need for tissue augmentation. We analyzed these outcomes against a panel of explanatory covariates.

RESULTS

Our study sample involved 370 site development procedures at 290 implant sites in 160 patients. Three factors exhibited statistically significant associations with need for tissue augmentation: alveolar ridge preservation (ARP) (odds ratio [OR] 0.28; 95% confidence interval [CI] 0.13, 0.57), immediate implant placement (IIP) (OR 0.21; 95% CI 0.10, 0.47), and implant submergence (OR 8.3; 95% CI 4.5, 15.3). Four factors predicted treatment complications: ARP (OR 6.1; 95% CI 1.3, 29.1), IIP (OR 6.1; 95% CI 1.06, 35.3), implant submergence (OR 5.3; 95% CI 1.1, 24.9), and mandibular arch (OR 31.3; 95% CI 1.9, 500). Anterior sites (OR 2.7; 95% CI 1.3, 5.8) were more likely to receive IIP.

CONCLUSIONS

In the evaluated sample, implant placement at a site exhibiting a favorable volume of native bone was rare. Seventy-eight percent of sites received hard tissue grafting during the treatment phase. The use of ARP or IIP at tooth extraction reduced subsequent tissue augmentation requirements. Education and training in ARP and other site development procedures may enhance the clinical practice and treatment outcomes of implant surgeons.

Varicocele at high altitude. Venous outflow restriction by hypobaric hypoxia?

BACKGROUND

Testicular aches have been reported to occur on exposure to high altitude (HA). As a painful expression of venous congestion at the pampiniform plexus, varicocele (VC) might be a consequence of cardiovascular adjustments at HA. Chile's National Social Security Regulatory Body (SUSESO) asked to evaluate this condition in the running follow-up study "Health effects of exposure to chronic intermittent hypoxia in Chilean mining workers."

OBJECTIVES

To investigate the prevalence of VC in a population usually shifting between sea level and HA, thereby intermittently being exposed to hypobaric hypoxia.

METHODOLOGY

Miners (n=492) agreed to be examined at their working place by a physician, in the context of a general health survey, for the presence of palpable VC, either visible or not. Among them was a group exposed to low altitude (LA) <2,400 m; n=123; another one, exposed to moderate high altitude (MHA) working 3,050 m; n=70, and a third one exposed to very high altitude (VHA) >3,900 m, n=165. The Chi2 test and Kruskal-Wallis test were used in the descriptive analysis, and logistic regression was applied to evaluate the association of VC with exposure to HA. The Ethics Committee for Research in Human Beings, Faculty of Medicine, University of Chile, approved this project.

RESULTS

VC prevalence (grades 2 and 3) was found to be 10% at LA, 4.1% at MHA and 16.7% at VHA (p≤0.05). Hemoglobin oxygen saturation (SaO2) was lower, and hemoglobin concentrations were higher in workers with high grade VC at VHA compared with LA and MHA (Wilcoxon tests, p<0.001). Odds ratios (OR) for association of VC with HA were 3.7 (95%CI: 1.26 to 12.3) and 4.06 (95%CI: 1.73 to 11.2) for MHA and VHA, respectively Conclusions: Association of VC with HA, a clinically relevant finding for its own sake, may be related to blood volume centralization as mediated by hypobaric hypoxia.

Two-Minute Step Test as a Complement to Six-Minute Walk Test in Subjects With Treated Coronary Artery Disease

The 2-Minute Step Test (2MST) has been presented as an alternative to the 6-Minute Walk Test (6MWT) based on the association between the two tests in older adults; however, some authors propose that it should not be a substitute but rather a complement to the latter in the fitness evaluation. Specifically, in coronary disease, despite the potential and clinical utility of 2MST, the relationship of both tests in this population is unknown. This study aimed to determine the relationship between 6MWT and 2MST and to explore the relationship of biodemographic factors for both tests in subjects with treated coronary artery disease. For this, the 6MWT and the 2MST were applied to patients with coronary artery disease treated in 6 hospitals in Chile between May 2019 and February 2020. Additionally, lower limb strength was assessed by a chair-stand test, grip strength was assessed by a dynamometer, and physical measurements were applied. In total, 163 participants underwent both tests (average age = 58.7 ± 9.8 years; 73.6% men; 64.4% revascularized by angioplasty; 28.2% revascularized by surgery, and 7.4% treated by drugs or thrombolysis). Heart rate was higher at the end of the 6MWT, while the perception of effort was greater at the end of the 2MST. There was a weak positive correlation between the 6MWT and the 2MST in subjects with treated coronary disease (r = 0.28, p = 0.0003). While age (r = –0.27), weight (r = 0.25), height (r = 0.49), and strength of both lower limbs (r = 0.41) and grip strength (r = 0.53) correlated weakly or moderately to the covered distance in 6MWT, the number of steps by the 2MST correlated only weakly to height (r = 0.23), lower limb strength (r = 0.34), and grip strength (r = 0.34). Age, weight, height, lower limb strength, and grip strength would explain better the meters walked in the 6MWT than the steps achieved in the 2MST. With these findings, we can conclude that, in patients with treated coronary artery disease, it does not seem advisable to replace 6MWT with 2MST when it is possible to do so. Additionally, the 2MST may provide additional information in the fitness evaluation. However, the usefulness of 2MST in this population needs to be further studied.

Association between eating habits and quality of life among Chilean university students

Objective To estimate the association between eating habits and quality of life (QOL) in Chilean university students. Participants: 1,212 students from the Universidad de La Frontera, Chile (mean age 18.7 ± 2.15) were surveyed in January-March 2018. Methods: Participants completed a cross-sectional self-report survey to evaluate QOL using the WHOQOL-BREF scale and eating habits with a food habits survey. Results: Students reporting a better healthy eating habits score also presented a higher QOL. Eating breakfast and eating home-cooked meals is a protective factor for QOL in each domain. The consumption of sweet snacks was shown to be a risk factor for the physical health and environment domains. The consumption of fast food is shown as the greatest risk factor in the physical domain. Conclusion: Healthy and unhealthy eating habits are associated with different dimensions of QOL. University authorities should develop new policies to improve the QOL of the entire university community.

A cross sectional study found differential risks for COVID-19 seropositivity amongst health care professionals in Chile

Objective

Health care workers (HCWs) are at increased risk for SARS-CoV-2 infection, however not all face the same risk. We aimed to determine IgG/IgM prevalence and risk factors associated with seropositivity in Chilean HCWs.

Study Design and Setting

This was a nationwide, cross-sectional study including a questionnaire and COVID-19 lateral flow IgG/IgM antibody testing. All HCWs in the Chilean public health care system were invited to participate following the country's first wave.

Results

IgG/IgM positivity in 85,529 HCWs was 7.2%, ranging from 1.6% to 12.4% between regions. Additionally, 9.7% HCWs reported a positive PCR of which 47% were seropositive. Overall, 10,863 (12.7%) HCWs were PCR and/or IgG/IgM positive. Factors independently associated with increased odds ratios (ORs) for seropositivity were: working in a hospital, night shifts, contact with Covid-19, using public transport, male gender, age>45, BMI ≥30, and reporting ≥2 symptoms. Stress and/or mental health disorder and smoking were associated with decreased ORs. These factors remained significant when including PCR positive cases in the model.

Conclusions

HCWs in the hospital were at highest risk for COVID-19, and several independent risk factors for seropositivity and/or PCR positivity were identified.

[Prevalence and incidence of ictus in Europe: systematic review and meta-analysis]

BACKGROUND

Stroke is the second cause of death and the first cause of disability in Europe. The number of stroke patients shows a rapidly increasing due to the increase in the elderly population. The aim of this meta-analysis is to evaluate the prevalence and incidence of stroke in Europe.

METHOD

We conducted a literature search in MEDLINE, SCOPUS, CINAHL Complete and EMBASE, using the keywords "stroke", "cerebrovascular accident", "epidemiology", "prevalence", "incidence" and "Europe". In order to evaluate the quality and risk of bias, we used the Hoy's modified scale for prevalence studies and the Newcastle Ottawa Scale for incidence studies. A random effects model with 95% confidence intervals (95%CI) was used for the meta-analysis. The I2 statistic was applied to assess heterogeneity.

RESULTS

The prevalence of stroke in Europe adjusted for sex was estimated at 9.2% (95%CI: 4.4-14.0). The prevalence was 9.1% (95%CI: 4.7-13.6) in men and 9.2% (95%CI: 4.1-14.4) in women, and increased with age. The incidence of stroke in Europe adjusted for sex was 191.9 per 100,000 person-years (95%CI: 156.4-227.3); it was 195.7 per 100,000 person-years (95%CI: 142.4-249.0) in men and 188.1 per 100,000 person-years (95%CI: 138.6-237.7) in women. Again, these rates increased with age.

CONCLUSION

The prevalence of stroke in Europe is 9.2%. The incidence of stroke in Europe is 191.9 per 100,000 person-years. The prevalence of stroke has increased, whereas the incidence of stroke is stable in comparison with studies conducted at the beginning of the 21st century.

Health Effects of Chronic Intermittent Hypoxia at a High Altitude among Chilean Miners: Rationale, Design, and Baseline Results of a Longitudinal Study

OBJECTIVES

This study aims to assess the health effects on mining workers of exposure to chronic intermittent hypoxia (CIH) at high- and very high-altitude mining compared with similar work at lower altitudes in Chile, and it also aims to constitute the baseline of a 5-year follow-up study.

METHODS

We designed a cross-sectional study to assess health conditions in 483 miners working at 2 levels of altitude exposure: 336 working at a very high or high altitude (HA; 247 above 3900-4400 m, and 89 at 3000-3900 m), and 147 below 2400 m. Subjects were randomly selected in two stages. First, a selection of mines from a census of mines in each altitude stratum was made. Secondly, workers with less than 2 years of employment at each of the selected mines were recruited. The main outcomes measured at the baseline were mountain sickness, sleep alterations, hypertension, body mass index, and neurocognitive functions.

RESULTS

Prevalence of acute mountain sickness (AMS) was 28.4% in the very high-altitude stratum (P = 0.0001 compared with the low stratum), and 71.7% experienced sleep disturbance (P = 0.02). The adjusted odds ratio for AMS was 9.2 (95% confidence interval: 5.2-16.3) when compared with the very high- and low-altitude groups. Motor processing speed and spatial working memory score were lower for the high-altitude group. Hypertension was lower in the highest-altitude subjects, which may be attributed to preoccupational screening even though this was not statistically significant.

CONCLUSIONS

Despite longer periods of acclimatization to CIH, subjects continue to present AMS and sleep disturbance. Compromise of executive functions was detected, including working memory at HA. Further rigorous research is warranted to understand long-term health impacts of high-altitude mining, and to provide evidence-based policy recommendations.

Treatment of skeletal and non-skeletal alterations of Mucopolysaccharidosis type IVA by AAV-mediated gene therapy

Mucopolysaccharidosis type IVA (MPSIVA) or Morquio A disease, a lysosomal storage disorder, is caused by N-acetylgalactosamine-6-sulfate sulfatase (GALNS) deficiency, resulting in keratan sulfate (KS) and chondroitin-6-sulfate accumulation. Patients develop severe skeletal dysplasia, early cartilage deterioration and life-threatening heart and tracheal complications. There is no cure and enzyme replacement therapy cannot correct skeletal abnormalities. Here, using CRISPR/Cas9 technology, we generate the first MPSIVA rat model recapitulating all skeletal and non-skeletal alterations experienced by patients. Treatment of MPSIVA rats with adeno-associated viral vector serotype 9 encoding Galns (AAV9-Galns) results in widespread transduction of bones, cartilage and peripheral tissues. This led to long-term (1 year) increase of GALNS activity and whole-body correction of KS levels, thus preventing body size reduction and severe alterations of bones, teeth, joints, trachea and heart. This study demonstrates the potential of AAV9-Galns gene therapy to correct the disabling MPSIVA pathology, providing strong rationale for future clinical translation to MPSIVA patients.

Gallbladder cancer who is really cured?

BACKGROUND

Although gallbladder cancer (GBCA) is characterized by a dismal prognosis, there is a proportion of patients who are cured. The aim of this study was to analyze the profile of these patients.

METHODS

A database was queried for patients who underwent curative resection with a follow-up of at least 5 years. Patients were prospectively treated and registered by the same surgical team. A multivariate regression analysis was used to identify factors associated with long-term survival.

RESULTS

From 1988 to 2013, 461 patients were evaluated and 112 who underwent resection were analyzed. Among the patients, five year survival was 57% while lymph node and liver compromise were the only independent factors associated with survival. On the other hand, the elapsed time between the cholecystectomy and the resection, the differentiation grade and the level of wall invasion did not have an independent effect on the prognosis.

CONCLUSION

Despite its poor prognosis, a subset of patients can be cured of GBCA. R0 resection of patients without lymph and liver infiltration are key to GBCA survival.

[Diagnostic properties of case definitions of suspected COVID-19 in Chile, 2020Características diagnósticas das definições de caso suspeito de COVID-19 no Chile, 2020]

Objective

Compare the diagnostic properties of five case definitions of suspected COVID-19 that were used or proposed in Chile during the first eight months of the pandemic.

Methods

An analysis was done of the diagnostic properties (sensitivity, specificity, and positive and negative predictive values) of three case definitions of suspected COVID-19 used in Chile between March and October 2020, as well as two alternative proposed definitions. The sample was 2,019 people with known results for the polymerase chain reaction (PCR) test for SARS-CoV-2. Stepwise logistic regression was used to develop criterion 5, optimizing sensitivity and specificity values. Multifactor logistic regression was used to explore the association between demographic variables, symptoms and signs, and PCR positivity. Different positivity scenarios were analyzed and ROC curves were compared.

Results

The presence of anosmia (OR = 8.00; CI95%: 5.34-11.99), fever (OR = 2.15; CI95%: 1.28-3.59), and having been in close contact with a person sick with COVID-19 (OR = 2.89; CI95%: 2.16-3.87) were associated with a positive PCR result. According to the analysis of the ROC curve, criterion 5 had the highest capacity for discrimination, although there were no significant differences with the other four criteria.

Conclusions

Criterion 5-based on anosmia, close contact with people with COVID-19, and fever as sufficient unique elements-was the most sensitive in identifying suspected cases of COVID-19, a key aspect in controlling the spread of the pandemic.

A Track Geometry Measuring System Based on Multibody Kinematics, Inertial Sensors and Computer Vision

This paper describes the kinematics used for the calculation of track geometric irregularities of a new Track Geometry Measuring System (TGMS) to be installed in railway vehicles. The TGMS includes a computer for data acquisition and process, a set of sensors including an inertial measuring unit (IMU, 3D gyroscope and 3D accelerometer), two video cameras and an encoder. The kinematic description, that is borrowed from the multibody dynamics analysis of railway vehicles used in computer simulation codes, is used to calculate the relative motion between the vehicle and the track, and also for the computer vision system and its calibration. The multibody framework is thus used to find the formulas that are needed to calculate the track irregularities (gauge, cross-level, alignment and vertical profile) as a function of sensor data. The TGMS has been experimentally tested in a 1:10 scaled vehicle and track specifically designed for this investigation. The geometric irregularities of a 90 m-scale track have been measured with an alternative and accurate method and the results are compared with the results of the TGMS. Results show a good agreement between both methods of calculation of the geometric irregularities.

Prevalencia y factores de riesgo para sífilis en población indígena masculina de Paraguay, 2017

Objetivo. Determinar la prevalencia y los factores de riesgo para sífilis en población indígena masculina de Paraguay durante el año 2017. Material y métodos. Se realizó un estudio observacional, descriptivo, con muestro probabilístico, estratificado y multietápico. Fueron incluidos indígenas de sexo masculino, mayores de 15 años de edad, de cinco familias lingüísticas residentes en Paraguay durante el periodo de estudio. Resultados. La prevalencia de sífilis en hombres de la población indígena de Paraguay fue de 4.50%. Los indígenas que tenían entre 15 y 20 años tuvieron 2.70 probabilidades de presentar sífilis. Asimismo, los participantes que reportaron múltiples parejas en el último año, sexo transaccional y consumir alcohol en la última relación sexual tuvieron 2.69, 3.06 ym 2.16 veces la probabilidad de presentar sífilis, respectivamente. Conclusiones. Se encontró una prevalencia moderada de sífilis en la población indígena masculina. La prevalencia fue de dos veces más para aquéllos que tenían más de dos parejas sexuales, sexo transaccional y que involucraban alcohol durante la práctica sexual.

High HIV prevalence among transgender women in Paraguay

Transgender women have been understudied and underserved in Paraguay; data are urgently needed to understand their HIV prevention and care needs. To estimate HIV prevalence and related risk and preventive behaviors among trans women in Paraguay, we conducted a cross-sectional survey in 2017. We employed starfish sampling - a hybrid venue-based and peer-referral method combining recruitment at randomly sampled venues and randomly selected clients from program lists, followed by short-chain referrals of eligible peers. Among 304 trans women enrolled, HIV prevalence was 24.8% (95% confidence interval [CI] 18.5-31.2%), with risk increasing with age (adjusted odds ratio [AOR] 1.06 per year, 95% CI 1.03-1.10), residence in Asunción department (AOR 4.75, 95% CI 1.57-14.36), and cocaine use (AOR 2.09, 95% CI 1.11-3.95). Trans women in Paraguay need to be prioritized for interventions with high HIV prevention efficacy. Substance use interventions to address cocaine use may also yield prevention benefits for trans women in our context.

Trends in mortality from stroke in the European Union, 1996-2015

BACKGROUND AND PURPOSE

Stroke is the second largest single cause of death in Europe, responsible for 9% and 13% of all deaths in men and women, respectively. There have been large overall declines in stroke mortality rates in the majority of European countries in recent decades. The aim of this study was to analyse trends in mortality caused by stroke in the 28 member countries of the European Union (EU) over the last two decades.

METHODS

We extracted data for age-standardized stroke mortality rates per 100 000 in the EU for the period 1996-2015 from the World Health Organization database. Joinpoint regression analysis was used to analyse the trends and compute the annual percent change (APC) in the EU as a whole and by country. Analyses were conducted by gender and by European region.

RESULTS

Mortality from stroke has decreased in the EU over the study period by an average APC of 4.2%. All countries showed downward trends, with the sharpest decreases in Estonia, Portugal and Austria. We recorded statistically significant decreases of 4.2% and 4.3% in mortality rates in men and women, respectively, in the whole EU. Southern and western countries showed the steepest decreases, whereas mortality has increased in northern countries in recent years.

CONCLUSIONS

Stroke mortality has decreased in the EU, in both sexes, especially in southern and western European countries. Our results could be a reference for the development of primary prevention and acute management of stroke policies focused on countries with higher mortality.

The Correlation between the Water Content and Electrolyte Permeability of Cation-Exchange Membranes

The salt permeability through three commercial cation-exchange membranes with different morphologies is investigated in aqueous NaCl solutions. Ion-exchange membranes (IEMs) find application in different processes such as electrodialysis, reverse osmosis, diffusion dialysis, membrane electrolysis, membrane fuel cells and ion exchange bioreactors. The aim of this paper is the experimental determination of the electrolyte permeability in the following membranes: MK-40 membrane, Nafion N324 membrane and Nafion 117 membrane. The latter is selected as being a reference membrane. The effect of an increase in the NaCl concentration in the solutions on membranes transport properties is analyzed. With regard to membranes sorption, a decrease in the water content was observed when the external electrolyte concentration is increased. Concerning permeation through the membranes, the salt permeability increased with concentration for the Nafion 117 membrane and remained nearly constant for the other two membranes. A close relation between the degree of liquid sorption by the membranes and the electrolyte permeability was observed.

Autoimmune and demyelinating optic neuritis

The knowledge on demyelinating and autoimmune optic neuropathies has experienced a revolution the last decade since the discovery of anti-aquaporin 4 antibody. Improvements in diagnostic techniques, and the finding of new targets, along with advances in neuro-immunology have led to the detection of antibodies related to demyelinating diseases. A review is presented on the classical and new concepts in optic neuritis. The debate on the classification of demyelinating and autoimmune optic neuritis is presented. Furthermore, the updated diagnostic criteria in multiple sclerosis and neuro-myelitis optics are described. Finally, the latest insights into Myelin Oligodendrocyte Glycoprotein (MOG) disorders and chronic-recurring optic neuropathies (CRION) are highlited.

Application and Experimental Validation of a Multibody Model with Weakly Coupled Lateral and Vertical Dynamics to a Scaled Railway Vehicle

In this paper, a multibody dynamic model of a railway vehicle that assumes that vertical and lateral dynamics are weakly coupled, has been experimentally validated using an instrumented scaled vehicle running on a 5-inch-wide experimental track. The proposed linearised model treats the vertical and lateral dynamics of the multibody system almost independently, being coupled exclusively by the suspension forces. Several experiments have been carried out at the scaled railroad facilities at the University of Seville in order to test and validate the simulation model under different working conditions. The scaled vehicle used in the experiments is a bogie instrumented with various sensors that register the accelerations and angular velocities of the vehicle, its forward velocity, its position along the track, and the wheel–rail contact forces in the front wheelset. The obtained results demonstrate how the proposed computational model correctly reproduces the dynamics of the real mechanical system in an efficient computational manner.

UAP56/DDX39B is a major cotranscriptional RNA-DNA helicase that unwinds harmful R loops genome-wide

In this study, Pérez-Calero et al. set out to investigate the role of UAP56/DDX39B in R-loop removal. Using in vitro and in vivo approaches, the authors demonstrate that UAP56 functions as a DNA–RNA helicase required to eliminate harmful cotranscriptional RNA structures that otherwise would block transcription and replication.

Nonscheduled R loops represent a major source of DNA damage and replication stress. Cells have different ways to prevent R-loop accumulation. One mechanism relies on the conserved THO complex in association with cotranscriptional RNA processing factors including the RNA-dependent ATPase UAP56/DDX39B and histone modifiers such as the SIN3 deacetylase in humans. We investigated the function of UAP56/DDX39B in R-loop removal. We show that UAP56 depletion causes R-loop accumulation, R-loop-mediated genome instability, and replication fork stalling. We demonstrate an RNA–DNA helicase activity in UAP56 and show that its overexpression suppresses R loops and genome instability induced by depleting five different unrelated factors. UAP56/DDX39B localizes to active chromatin and prevents the accumulation of RNA–DNA hybrids over the entire genome. We propose that, in addition to its RNA processing role, UAP56/DDX39B is a key helicase required to eliminate harmful cotranscriptional RNA structures that otherwise would block transcription and replication.

Adaptation and validation of the PEDSQL™ oral health scale for toddlers in Chilean population

BACKGROUND

The Pediatric Quality of Life Inventory™ (PedsQL™) Oral Health Scale was developed to measure oral health-related quality of life (OHRQoL). The aim of this study was to cross-culturally adapt the parent-reported version for toddlers of PedsQL™ Oral Health Scale into Spanish and to assess the acceptability, reliability and validity of this version in Chilean preschool population.

METHODS

The PedsQL™ Oral Health Scale for toddlers was cross-culturally adapted for the Spanish language using the recommended standards. To assess metric properties, a cross-sectional study was carried out with 301 children aged 2 to 5 years in Carahue, Chile. Chilean versions of the PedsQL™ Oral Health Scale, PedsQL™ 4.0 Generic Core Scales, and Early Childhood Oral Health Impact Scale (ECOHIS) were completed by the children's parents. Dental caries, malocclusion and dental trauma were examined by trained dentists. The PedsQL™ Oral Health Scale was administrated a second time 14-21 days after. The reliability of the scale was verified by analysis of internal consistency (Cronbach's alpha) and reproducibility (Intraclass correlation coefficient - ICC). The validity of the construct was assessed by confirmatory factor analysis and known groups method. The convergent validity was assessed by calculating the Spearman's correlation with the ECOHIS questionnaire.

RESULTS

The PedsQL™ Oral Health Scale demonstrated good reliability, with Cronbach's alpha coefficient of 0.79 and ICC of 0.85. A moderate-to-strong correlation was found between the PedsQL™ Oral Health Scale and the ECOHIS questionnaire (- 0.64); the PedsQL™ Oral Health Scale score was lower in children with poor than those with excellent/very good oral health (median 100 vs 85, p < 0.001); it also was lower in children with caries than in those caries-free (median 100 vs 90, p < 0.001). No statistically significant differences were found among groups according to malocclusion and traumatic dental injuries.

CONCLUSIONS

The PedsQL™ Oral Health Scale for toddlers in Spanish showed to be equivalent to the original version, and its psychometric properties were satisfactory for application in a Chilean pre-school population.

Differences in clinical manifestations and increased severity of systemic lupus erythematosus between two groups of Hispanics: European Caucasians versus Latin American mestizos (data from the RELESSER registry)

Background

Systemic lupus erythematosus (SLE) is regarded as a prototype autoimmune disease because it can serve as a means for studying differences between ethnic minorities and sex. Traditionally, all Hispanics have been bracketed within the same ethnic group, but there are differences between Hispanics from Spain and those from Latin America, not to mention other Spanish-speaking populations.

Objectives

This study aimed to determine the demographic and clinical characteristics, severity, activity, damage, mortality and co-morbidity of SLE in Hispanics belonging to the two ethnic groups resident in Spain, and to identify any differences.

Methods

This was an observational, multi-centre, retrospective study. The demographic and clinical variables of patients with SLE from 45 rheumatology units were collected. The study was conducted in accordance with Good Clinical Practice guidelines. Hispanic patients from the registry were divided into two groups: Spaniards or European Caucasians (EC) and Latin American mestizos (LAM). Comparative univariate and multivariate statistical analyses were carried out.

Results

A total of 3490 SLE patients were included, 90% of whom were female; 3305 (92%) EC and 185 (5%) LAM. LAM patients experienced their first lupus symptoms four years earlier than EC patients and were diagnosed and included in the registry younger, and their SLE was of a shorter duration. The time in months from the first SLE symptoms to diagnosis was longer in EC patients, as were the follow-up periods. LAM patients exhibited higher prevalence rates of myositis, haemolytic anaemia and nephritis, but there were no differences in histological type or serositis. Anti-Sm, anti-Ro and anti-RNP antibodies were more frequently found in LAM patients. LAM patients also had higher levels of disease activity, severity and hospital admissions. However, there were no differences in damage index, mortality or co-morbidity index. In the multivariate analysis, after adjusting for confounders, in several models the odds ratio (95% confidence interval) for a Katz severity index >3 in LAM patients was 1.45 (1.038–2.026; p = 0.02). This difference did not extend to activity levels (i.e. SLEDAI >3; 0.98 (0.30–1.66)).

Conclusion

SLE in Hispanic EC patients showed clinical differences compared to Hispanic LAM patients. The latter more frequently suffered nephritis and higher severity indices. This study shows that where lupus is concerned, not all Hispanics are equal.

Population-Based Cataract Surgery Complications and Their Impact on Visual Status in the Brazilian Amazon Region

PURPOSE

To investigate cataract surgery prevalence, complications, visual outcomes, and coverage in a population of older adults from the Brazilian Amazon region.

DESIGN

Population-based cross-sectional study.

METHODS

Individuals ≥45 years of age from urban and rural areas of Parintins City, Brazil, were identified by cluster random sampling. Participants underwent ophthalmic examination, including uncorrected visual acuity, acuity with presenting correction (APC), and best-corrected visual acuity (BCVA) from each eye. In those with previous cataract surgery, surgical technique and complications including its contribution to vision impairment were noted. The association of surgical complications and surgical coverage with sociodemographic variables was assessed by multiple logistic regression.

RESULTS

A total of 2,384 persons were determined to be eligible, and 2,041 (85.6%) were examined. Overall, prevalence of cataract surgery was 8.6%, with 11.3% urban and 5.0% rural. Surgical complications were associated with males, older age, and urban residency and were found in 60.4%, with posterior capsule opacification in 29.6% and posterior capsule rupture in 16.3%. Among the 270 eyes having cataract surgery, APC ≥20/32 was found in 44.4%, APC 20/40 to 20/63 in 20.8%, APC <20/63 to 20/200 in 14.4%, APC <20/200 to 20/400 in 2.6%, and APC <20/400 in 17.8%. Low surgical coverage was found with 57.9% of those with visual impairment due to cataract not being treated surgically.

CONCLUSIONS

Although a reasonable prevalence of cataract surgery was found, a high complication rate, poor visual outcomes, and low cataract surgery coverage indicated that actions to improve quality and appropriate postsurgical management should be planned and implemented by public health authorities.