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.

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.

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.

Hybrid Cardiac Rehabilitation Program in a Low-Resource Setting: A Randomized Clinical Trial.

Importance: While effective, cardiovascular rehabilitation (CR) as traditionally delivered is not well implemented in lower-resource settings. Objective: To test the noninferiority of hybrid CR compared with traditional CR in terms of cardiovascular events. Design, Setting, and Participants: This pragmatic, multicenter, parallel arm, open-label randomized clinical trial (the Hybrid Cardiac Rehabilitation Trial [HYCARET]) with blinded outcome assessment was conducted at 6 referral centers in Chile. Adults aged 18 years or older who had a cardiovascular event or procedure, no contraindications to exercise, and access to a mobile telephone were eligible and recruited between April 1, 2019, and March 15, 2020, with follow-up until July 29, 2021. Interventions: Participants were randomized 1:1 in permuted blocks to the experimental arm, which received 10 center-based supervised exercise sessions plus counseling in 4 to 6 weeks and then were supported at home via telephone calls and text messages through weeks 8 to 12, or the control arm, which received the standard CR of 18 to 22 sessions with exercises and education in 8 to 12 weeks. Main Outcomes and Measures: The primary outcome was cardiovascular events or mortality. Secondary outcomes were quality of life, return to work, and lifestyle behaviors measured with validated questionnaires; muscle strength and functional capacity, measured through physical tests; and program adherence and exercise-related adverse events, assessed using checklists. Results: A total of 191 participants were included (mean [SD] age, 58.74 [9.80] years; 145 [75.92%] male); 93 were assigned to hybrid CR and 98 to standard CR. At 1 year, events had occurred in 5 unique participants in the hybrid CR group (5.38%) and 9 in the standard CR group (9.18%). In the intention-to-treat analysis, the hybrid CR group had 3.80% (95% CI, -11.13% to 3.52%) fewer cardiovascular events than the standard CR group, and relative risk was 0.59 (95% CI, 0.20-1.68) for the primary outcome. In the per-protocol analysis at different levels of adherence to the intervention, all 95% CIs crossed the noninferiority boundary (eg, 20% adherence: absolute risk difference, -0.35% [95% CI, -7.56% to 6.85%]; 80% adherence: absolute risk difference, 3.30% [95% CI, -3.70% to 10.31%]). No between-group differences were found for secondary outcomes except adherence to supervised CR sessions (79.14% [736 of 930 supervised sessions] in the hybrid CR group vs 61.46% [1201 of 1954 sessions] in the standard CR group). Conclusions and Relevance: The results suggest that a hybrid CR program is noninferior to standard center-based CR in a low-resource setting, primarily in terms of recurrent cardiovascular events and potentially in terms of intermediate outcomes. Hybrid CR may induce superior adherence to supervised exercise. Clinical factors and patient preferences should inform CR model allocation. Trial Registration: ClinicalTrials.gov Identifier: NCT03881150.

Influence of different midsole foam in advanced footwear technology use on running economy and biomechanics in trained runners.

BACKGROUND: Ethylene and vinyl acetate (EVA) and polyether block amide (PEBA) are recently the most widely used materials for advanced footwear technology (AFT) that has been shown to improve running economy (RE). This study investigated the effects of these midsole materials on RE and biomechanics, in both fresh and worn state (after 450 km). METHODS: Twenty-two male trained runners participated in this study. Subjects ran four 4-min trials at 13 km‧h-1 with both fresh EVA and PEBA AFT and with the same models with 450 km of wear using a randomized crossover experimental design. We measured energy cost of running (W/kg), spatiotemporal, and neuromuscular parameters. RESULTS: There were significant differences in RE between conditions (p = 0.01; n2 = 0.17). There was a significant increase in energy cost in the worn PEBA condition compared with new (15.21 ± 1.01 and 14.87 ± 0.99 W/kg; p < 0.05; ES = 0.54), without differences between worn EVA (15.13 ± 1.14 W/kg; p > 0.05), and new EVA (15.15 ± 1.13 w/kg; ES = 0.02). The increase in energy cost between new and worn was significantly higher for the PEBA shoes (0.32 ± 0.38 W/kg) but without significant increase for the EVA shoes (0.06 ± 0.58 W/kg) (p < 0.01; ES = 0.51) with changes in step frequency and step length. The new PEBA shoes had lower energy cost than the new EVA shoes (p < 0.05; ES = 0.27) with significant differences between conditions in contact time. CONCLUSION: There is a clear RE advantage of incorporating PEBA versus EVA in an AFT when the models are new. However, after 450 km of use, the PEBA and EVA shoes had similar RE.

Asociación entre utilización de Guía de Referencia Clínica a Ortodoncia y derivación pertinente

Objetivo Los Servicios de Salud en Chile tienen una demanda insatisfecha en ortodoncia y muchas de las interconsultas no son pertinentes. Buscando una solución, el Servicio de Salud Metropolitano Norte (SSMN) implementó la "Guía de Referencia Clínica Ortodoncia (GRCO) para Servicios Públicos de Salud". El objetivo de este estudio fue evaluar si existe asociación entre utilizar GRCO y pertinencia en derivaciones a Ortodoncia realizadas por odontólogos de Atención Primaria. Materiales y Métodos Se realizó un estudio observacional analítico en 167 pacientes derivados por odontólogos que utilizaron la GRCO y 167 pacientes derivados por odontólogos que no la utilizaron. Una especialista en ortodoncia evaluó pertinencia en la derivación. Los datos se analizaron mediante la prueba de chi-cuadrado, y la prueba t-test. Resultados De los odontólogos que usaron la guía solo un 3% de sus derivaciones fueron no pertinentes, mientras que aquellos que no la usaron, tuvieron un 54% de derivaciones no pertinentes (p <0,001). Odontólogos que no usan la GRCO presentan 38 veces más probabilidad de realizar una derivación no pertinente. (OR 38,8; IC 14,9 - 125,9). Conclusión El uso de Guía de Referencia Clínica a Ortodoncia se asocia fuertemente con la pertinencia en la derivación de pacientes a la especialidad ortodoncia.

Objective. Health Services in Chile have an unsatisfied demand in orthodontics and the largest waiting list for dental specialties, with many of the referrals being irrelevant. Seeking a solution, the North Metropolitan Health Service (SSMN) implemented the "Orthodontic Clinical Referral Guideline (GRCO) for Public Health Services", to define the appropriateness of referrals. The objective of this study was to assess whether there is an association between the GRCO and the appropriateness of orthodontic referrals made by Primary Health Care dentists of the SSMN. Materials and methods. An analytical observational study was carried out in 167 patients referred by dentists who used the GRCO and 167 patients referred by dentists who did not use it. A calibrated orthodontic specialist assessed the relevance of the referral. The data was analyzed using the chi-square test, and the t-test. Results. Only 3% of the referrals made by dentists who used the GRCO were inappropriate, compared to 54% of those who did not use it. Dentists who do not use the GRCO are 38 times more likely to make an inappropriate referral than those who adhere to the GRCO (OR 38.8; CI 14.9 - 125.9) Conclusion. The use of the Orthodontic Clinical Referral Guideline is strongly associated with appropriateness in referring patients to the orthodontic specialty.

Perfil de transmisión del SARS-COV-2 en una región sanitaria del Paraguay

Introducción: La transmisión viral a menudo se propaga en grupos, donde las infecciones se pueden rastrear hasta un caso índice o una ubicación geográfica, para así poder tomar medidas de prevención al respecto. Entender el perfil de transmisión del SARS-CoV-2 es esencial para desarrollar estrategias efectivas de prevención y control de la enfermedad. Objetivo: Determinar el perfil de transmisión del Sars-Cov-2, a partir de clúster con casos índices identificados, en la V región sanitaria (Caaguazu) del Paraguay, entre julio y octubre del 2020. Metodología: Se realizó un estudio observacional, descriptivo, de corte transversal, con fichas de notificación de casos de COVID-19 y resultados laboratoriales de la RT_PCR en pacientes diagnosticados con COVID-19 en la V Región Sanitaria entrejulio y octubre del 2020. Resultados: Fueron identificadas 703 personas con Sars-Cov-2 positivo. El 55,49 % de las personas no reconoció algún nexo de contagio. Con respecto al tipo de evento donde ocurrían con mayor frecuencia los contagios, ocurrieron en Eventos Sociales en 58,14 % de los casos y en el Ambiente Familiar en el 33,89 %. La transmisión secundaria se observó en el 17,40 % de los casos. Fueron identificados 58 Clústers, con una mediana de tamaño de los mismos de 3 (RIQ 2-4), y 267 personas (37,98 %) asociadas a los mismos. Discusión: La mayoría de las personas no reconocieron su nexo de contagio, sin embargo, en los que, si conocieron, se puede observar que la participación en eventos sociales fue el principal nexo, por lo que es fundamental realizar este tipo de ejercicios para hacer el seguimiento oportuno de los casos.

Introduction: Viral transmission often spreads in clusters, where infections can be traced to an index case or a geographic location, in order to take preventive measures in this regard, understanding the transmission profile of SARS-CoV-2 is essential. to develop effective disease prevention and control strategies. Objective: to determine the transmission profile of Sars-Cov-2, from clusters with identified index cases, in the V health region (Caaguazú) of Paraguay, between July and October 2020. Methodology: We carried out an observational, descriptive, cross-sectional study, with notification sheets of COVID-19 cases and laboratory results of the RT_PCR in patients diagnosed with COVID-19 in the V Sanitary Region between July and October 2020. Results: We identified 703 people with positive Sars-Cov-2. 55.49% of people did not recognize any contagion link. Regarding the type of event where infections occurred most frequently, was in Social Events in 58.14% of the cases and the Family Environment in 33.89%, secondary transmission was observed in 17.40% of the cases. 58 Clusters were identified, with a median size of 3 (IQR 2-4), and 267 people (37.98%) associated with them. Discussion: Most of the people did not recognize their contagion link, however, in those who did know, the main link was because they participated in social events, so it is essential to carry out this type of exercise to do timely follow-up. of the cases.

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.

Trends in mortality from cardiovascular diseases in Chile, 2000–2020 / Tendencias de la mortalidad por enfermedades cardiovasculares en Chile, 2000-2020 / Tendências de mortalidade por doenças cardiovasculares no Chile, 2000-2020

[ABSTRACT]. 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.

[RESUMEN]. Objetivo. Analizar las tendencias de la mortalidad por enfermedades cardiovasculares (ECV) en Chile durante el período 2000-2020. Métodos. Los datos sobre la tasa de mortalidad ajustada por la edad (TMAE) por ECV por 100 000 habitantes en Chile durante el período 2000-2020 se extrajeron de la base de datos de mortalidad de la Organización Mundial de la Salud. Se utilizó la regresión de tipo joinpoint (punto de cambio) para analizar las tendencias y calcular el cambio porcentual anual promedio (CPAP) en Chile. Además, se realizaron análisis por sexo y por tipo de ECV. Resultados. Entre el 2000 y el 2020, la TMAE por ECV disminuyó en Chile de 159,5 a 94,6 por 100 000 habi- tantes, con una disminución del CPAP estadísticamente significativa del 2,6% (IC del 95% [-2,8 a -2,4]). No se detectó ningún punto de cambio (joinpoint). La TMAE por ECV disminuyó anualmente un 2,6% (IC del 95% [-2,8 a -2,4]) en los hombres y un 2,8% (IC del 95% [-3,5 a -2,6]) en las mujeres. La TMAE por cardiopatía isquémica se redujo anualmente en un 3,6 % (IC del 95 % [-4,6 a -2,7]), encontrándose dos puntos de cambio en el 2011 y el 2015. En el caso de los ataques cerebrovasculares, la tasa de mortalidad disminuyó anual- mente un 3,7% (IC del 95% [-4,5 a -3,0]), encontrándose dos puntos de cambio en el 2008 y el 2011. Conclusiones. La tasa de mortalidad por ECV ha disminuido significativamente en Chile en ambos sexos, pero en especial en las mujeres. Este descenso podría explicarse principalmente por la reducción significa- tiva de la letalidad observada en las últimas décadas. Estos resultados podrían constituir una referencia para la elaboración de políticas de prevención primaria y manejo de casos agudos de ECV que estén centradas en aquellos grupos poblacionales donde la mortalidad es más alta.

[RESUMO]. Objetivo. Analisar as tendências de mortalidade causada por doenças cardiovasculares (DCV) no Chile no período de 2000 a 2020. Métodos. Taxas de mortalidade por DCV ajustadas por idade no Chile referentes ao período de 2000 a 2020 foram extraídas do Banco de Dados de Mortalidade da Organização Mundial da Saúde. Foi usado um modelo de regressão linear segmentada (joinpoint) para analisar tendências e calcular a variação percentual média anual no Chile. Além disso, foram realizadas análises por sexo e tipo de DCV. Resultados. No Chile, entre 2000 e 2020, a taxa de mortalidade por DCV ajustada por idade caiu de 159,5 para 94,6 por 100 mil habitantes, com uma redução estatisticamente significante da variação percentual média anual de 2,6% (IC de 95% [-2,8; -2,4]). Não foram identificados pontos de inflexão. Anualmente, a taxa de mortalidade por DCV ajustada por idade caiu 2,6% (IC 95% [-2,8; -2,4]) e 2,8% (IC 95% [-3,5; -2,6]) entre homens e mulheres, respectivamente. A taxa de mortalidade por doença cardíaca isquêmica ajustada por idade caiu 3,6% (95% CI [-4,6; -2,7]) por ano, com dois pontos de inflexão (em 2011 e 2015). No caso do acidente vascular cerebral, a taxa de mortalidade diminuiu 3,7% (IC de 95% [-4,5; -3,0]) por ano, com dois pontos de inflexão (em 2008 e 2011). Conclusões. As taxas de mortalidade por doenças cardiovasculares diminuíram significativamente no Chile em ambos os sexos, especialmente nas mulheres. Essa queda pode ser explicada principalmente por uma redução significativa na letalidade observada nas últimas décadas. Esses resultados podem ser uma referên- cia para o desenvolvimento de políticas de prevenção primária e manejo de casos agudos de DCV voltadas para populações com maiores taxas de mortalidade.

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.

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.

Thermal Conductivity of Carbon/Boron Nitride Heteronanotube and Boron Nitride Nanotube Buckypapers: Implications for Thermal Management Composites.

To date, there has been limited reporting on the fabrication and properties of macroscopic sheet assemblies (specifically buckypapers) composed of carbon/boron nitride core-shell heteronanotubes (MWCNT@BNNT) or boron nitride nanotubes (BNNTs). Herein we report the synthesis of MWCNT@BNNTs via a facile method involving Atmospheric Pressure Chemical Vapor Deposition (APCVD) and the safe h-BN precursor ammonia borane. These MWCNT@BNNTs were used as sacrificial templates for BNNT synthesis by thermal oxidation of the core carbon. Buckypaper fabrication was facilitated by facile sonication and filtration steps. To test the thermal conductivity properties of these new buckypapers, in the interest of thermal management applications, we have developed a novel technique of advanced scanning thermal microscopy (SThM) that we call piercing SThM (pSThM). Our measurements show a 14% increase in thermal conductivity of the MWCNT@BNNT buckypaper relative to a control multiwalled carbon nanotube (MWCNT) buckypaper. Meanwhile, our BNNT buckypaper exhibited approximately half the thermal conductivity of the MWCNT control, which we attribute to the turbostratic quality of our BNNTs. To the best of our knowledge, this work achieves the first thermal conductivity measurement of a MWCNT@BNNT buckypaper and of a BNNT buckypaper composed of BNNTs not synthesized by high energy techniques.

Factors Associated With Accidental Decannulation in Tracheostomized Children.

BACKGROUND: Tracheostomy has many benefits for pediatric patients in the ICU, but it is also associated with complications. Accidental decannulation (AD) is a frequent complication and cause of mortality in this population. Our study aimed to determine the factors associated with AD in tracheostomized pediatric subjects. METHODS: This was a case-control study with 1:2 allocation ratio. Participants were tracheostomized children hospitalized in a prolonged mechanical ventilation hospital between 2013-2018. Each child who experienced decannulation during the study period was included as a case at the time of the event. Controls were obtained from the same population and were defined as subjects without an AD event during the same period. RESULTS: One hundred forty patients were hospitalized at Josefina Martinez Hospital at the time, of whom 41 were selected as cases and 82 as controls. Median (interquartile range) age was 20 (12-36) months, being 60% male. The median time from tracheostomy placement to AD event was 364 (167-731) d. Eighty-four percent of subjects were mechanically ventilated. AD mainly occurred by self-decannulation (53.7%). The risk of AD was higher in children who reached the midline in a sitting position (odds ratio 9.5 [95% CI 1.59-53.90]), inner diameter (ID) tracheostomy tube size ≤ 4.0 mm (odds ratio 5.18 [95% CI 1.41-19.06]), and who had been hospitalized in hospital rooms with a low ratio of nursing staff for each subject (1 nurse to 4 subjects) (odds ratio 4.48 [95% CI 1.19-16.80]). CONCLUSIONS: Factors associated with a higher risk of AD in tracheostomized children included the ability to reach the midline in a sitting position, the use of a smaller tracheostomy tube (≤ 4.0 mm ID), and lower supervision from staff.

Multimerization of HIF enhances transcription of target genes containing the hypoxia ancillary sequence.

Transcriptional activity of the hypoxia inducible factor (HIF) relies on the formation of a heterodimer composed of an oxygen-regulated α-subunit and a stably expressed ß-subunit. Heterodimeric HIF activates expression by binding to RCGTG motifs within promoters of hypoxia-activated genes. Some hypoxia targets also possess an adjacent HIF ancillary sequence (HAS) reported to increase transcription but whose function remains obscure. Here, we investigate the contribution of the HAS element to the hypoxia response and its mechanism of action, using the HAS-containing prolyl 4-hydroxylase subunit α1 (P4HA1) as a gene model in NIH/3T3 mouse embryonic fibroblasts and HEK293 human embryonic kidney cells. Our HIF overexpression experiments demonstrate that the HAS motif is essential for full induction by hypoxia and that the presence of the tandem HAS/HIF, as opposed to HIF-only sequences, provides HIF proteins with the capacity to form complexes of stoichiometry beyond the classical heterodimer, likely tetramers, to cooperatively potentiate hypoxia-induced transcription. We also provide evidence of the crucial role played by the Fα helix of the PAS-B domain of the HIF1ß subunit to support the interaction between heterodimers. Functional analysis showed that human genes containing the HAS/HIF motifs are better responders to hypoxia, and their promoters are enriched for specific transcription factor binding sites. Gene ontology enrichment revealed a predominance of HAS/HIF in genes primarily related to tissue formation and development. Our findings add an extra level of regulation of the hypoxia/HIF signaling through multimerization of HIF proteins on regulatory elements containing the HAS/HIF motifs.

The mRNA and protein levels of the glycolytic enzymes lactate dehydrogenase A (LDHA) and phosphofructokinase platelet (PFKP) are good predictors of survival time, recurrence, and risk of death in cervical cancer patients.

INTRODUCTION: Patients with cervical cancer (CC) may experience local recurrence very often after treatment; when only clinical parameters are used, most cases are diagnosed in late stages, which decreases the chance of recovery. Molecular markers can improve the prediction of clinical outcome. Glycolysis is altered in 70% of CCs, so molecular markers of this pathway associated with the aggressiveness of CC can be identified. METHODS: The expression of 14 glycolytic genes was analyzed in 97 CC and 29 healthy cervical tissue (HCT) with microarray; only LDHA and PFKP were validated at the mRNA and protein levels in 36 of those CC samples and in 109 new CC samples, and 31 HCT samples by qRT-PCR, Western blotting, or immunohistochemistry. A replica analysis was performed on 295 CC from The Cancer Genome Atlas (TCGA) database. RESULTS: The protein expression of LDHA and PFKP was associated with poor overall survival [OS: LDHA HR = 4.0 (95% CI = 1.4-11.1); p = 8.0 × 10-3 ; PFKP HR = 3.3 (95% CI = 1.1-10.5); p = 4.0 × 10-2 ] and disease-free survival [DFS: LDHA HR = 4.5 (95% CI = 1.9-10.8); p = 1.0 × 10-3 ; PFKP HR = 3.2 (95% CI = 1.2-8.2); p = 1.8 × 10-2 ] independent of FIGO clinical stage, and the results for mRNA expression were similar. The risk of death was greater in patients with overexpression of both biomarkers than in patients with advanced FIGO stage [HR = 8.1 (95% CI = 2.6-26.1; p = 4.3 × 10-4 ) versus HR = 7 (95% CI 1.6-31.1, p = 1.0 × 10-2 )] and increased exponentially as the expression of LDHA and PFKP increased. CONCLUSIONS: LDHA and PFKP overexpression at the mRNA and protein levels was associated with poor OS and DFS and increased risk of death in CC patients regardless of FIGO stage. The measurement of these two markers could be very useful for evaluating clinical evolution and the risk of death from CC and could facilitate better treatment decision making.

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.