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1.
Sensors (Basel) ; 24(14)2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39066028

RESUMEN

This paper presents a deep learning approach for predicting rail corrugation based on on-board rolling-stock vertical acceleration and forward velocity measurements using One-Dimensional Convolutional Neural Networks (CNN-1D). The model's performance is examined in a 1:10 scale railway system at two different forward velocities. During both the training and test stages, the CNN-1D produced results with mean absolute percentage errors of less than 5% for both forward velocities, confirming its ability to reproduce the corrugation profile based on real-time acceleration and forward velocity measurements. Moreover, by using a Gradient-weighted Class Activation Mapping (Grad-CAM) technique, it is shown that the CNN-1D can distinguish various regions, including the transition from damaged to undamaged regions and one-sided or two-sided corrugated regions, while predicting corrugation. In summary, the results of this study reveal the potential of data-driven techniques such as CNN-1D in predicting rails' corrugation using online data from the dynamics of the rolling-stock, which can lead to more reliable and efficient maintenance and repair of railways.

2.
Prev Vet Med ; 229: 106241, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38878496

RESUMEN

Oral vaccination is one of the most effective interventions for disease control in wildlife. As a result of the recent global reemergence of African swine fever and ongoing classical swine fever and animal tuberculosis, oral vaccination of Eurasian wild boar (Sus scrofa) receives increased interest. Several baits for wild boar and feral pigs have been described, but developing more stable and personalized formulations is important. This paper proposes a new bait formulation primarily composed of corn flour, piglet feed, sugar, and honey as a binder to obtain improved elasticity. The bait consists of a matrix with no protective coats, has a hemispherical shape (ø 3.4 ×1.6 cm), and displays an anise aroma and blue color. The color and aroma did not affect bait choice by wild boar, while bait coloring contributed to avoid consumption by non-target species (corvids). Baits with the new formulation were significantly more resistant to humidity and high temperatures than previous versions. Simulations suggest that baits with the new formulation are elastic enough to resist impacts from a maximum altitude of 750 m. Thus, the new bait prototype solves several problems of previous bait formulations while keeping a format that can be selectively consumed by piglets and adult wild boar.


Asunto(s)
Sus scrofa , Animales , Administración Oral , Porcinos , Vacunación/veterinaria , Vacunación/métodos , Alimentación Animal/análisis , Vacunas/administración & dosificación , Miel/análisis , Zea mays , Animales Salvajes , Azúcares
3.
J Perinatol ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38844521

RESUMEN

OBJECTIVE: To explore the association between antenatal magnesium sulfate (MgSO4), mortality and incidence of intraventricular hemorrhage (IVH) in very low birth weight (VLBW) infants. STUDY DESIGN: Retrospective, cohort study of infants <32 weeks' GA born at centers of NEOCOSUR Network between January 2015 and December 2020. Subjects were categorized as exposed vs non-exposed to antenatal MgSO4. Primary outcomes were death, incidence of severe IVH (Grade III-IV) and severe IVH/death. Secondary outcomes included relevant morbidities. RESULTS: 7418 VLBW infants were eligible. Antenatal MgSO4 was associated with a significantly decreased death rate after admission (aOR 0.67 [95% CI, 0.49-0.94]) and severe IVH/ death (aOR 0.68 [95% CI, 0.50-0.93]). No significant reduction in severe IVH was observed (aOR 1.11 [95% CI, 0.72-1.71]). No differences between groups were observed in rates of morbidities. CONCLUSION: Antenatal MgSO4 was associated with a decreased death rate after admission and in severe IVH/ death.

4.
EMBO J ; 43(6): 1043-1064, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38360996

RESUMEN

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.


Asunto(s)
Proteínas de Unión al ADN , Recombinasa Rad51 , ADN/genética , Replicación del ADN , Proteínas de Unión al ADN/metabolismo , Proteína Homóloga de MRE11/metabolismo , Recombinasa Rad51/genética , Recombinasa Rad51/metabolismo , Humanos
5.
Cell Rep ; 43(2): 113778, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38341854

RESUMEN

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.


Asunto(s)
Proteínas de Ciclo Celular , Cromatina , Acetilación , Procesamiento Proteico-Postraduccional , ADN
6.
Mol Metab ; 81: 101899, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38346589

RESUMEN

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.


Asunto(s)
Enfermedad del Almacenamiento de Glucógeno Tipo II , Ratones , Ratas , Humanos , Animales , Enfermedad del Almacenamiento de Glucógeno Tipo II/genética , Enfermedad del Almacenamiento de Glucógeno Tipo II/terapia , Enfermedad del Almacenamiento de Glucógeno Tipo II/patología , Músculo Esquelético/metabolismo , Glucógeno/metabolismo , Terapia Genética/métodos , Cardiomegalia/metabolismo , Cardiomegalia/patología , Cardiomegalia/terapia
7.
JAMA Netw Open ; 7(1): e2350301, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38194236

RESUMEN

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.


Asunto(s)
Rehabilitación Cardiaca , Enfermedades Cardiovasculares , Teléfono Celular , Adulto , Humanos , Masculino , Persona de Mediana Edad , Femenino , Calidad de Vida , Lista de Verificación , Enfermedades Cardiovasculares/prevención & control
8.
Scand J Med Sci Sports ; 34(1): e14526, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37858294

RESUMEN

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.


Asunto(s)
Ácidos Borónicos , Carrera , Humanos , Masculino , Fenómenos Biomecánicos , Estudios Cruzados , Zapatos
9.
Med. clín. soc ; 7(3)dic. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1528990

RESUMEN

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.

10.
Int. j interdiscip. dent. (Print) ; 16(3): 187-190, dic. 2023. tab
Artículo en Español | LILACS | ID: biblio-1528751

RESUMEN

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.


Asunto(s)
Humanos , Masculino , Femenino , Ortodoncia , Pacientes , Guía de Práctica Clínica , Servicios de Salud Dental
11.
Rev Panam Salud Publica ; 47: e127, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38024444

RESUMEN

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.

13.
PLoS One ; 18(10): e0291604, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37788251

RESUMEN

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.


Asunto(s)
Ejercicio Físico , Masculino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Femenino , Chile , Reproducibilidad de los Resultados , Estudios Transversales , Encuestas y Cuestionarios
14.
Environ Geochem Health ; 45(12): 9891-9901, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37882916

RESUMEN

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.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Adulto , Humanos , Chile , Monitoreo del Ambiente/métodos , Metales Pesados/toxicidad , Metales Pesados/análisis , Estrés Oxidativo , Suelo , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Medición de Riesgo , China
15.
ACS Appl Nano Mater ; 6(17): 15374-15384, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37706066

RESUMEN

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.

16.
Respir Care ; 68(2): 173-179, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-37610360

RESUMEN

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.


Asunto(s)
Hospitales , Personal de Enfermería , Humanos , Niño , Masculino , Lactante , Femenino , Estudios de Casos y Controles , Oportunidad Relativa , Respiración Artificial
17.
Biochim Biophys Acta Gene Regul Mech ; 1866(4): 194963, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37499936

RESUMEN

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.


Asunto(s)
Proteínas de Unión al ADN , Factores de Transcripción , Animales , Humanos , Ratones , Factores de Transcripción/metabolismo , Proteínas de Unión al ADN/metabolismo , Células HEK293 , ARN Mensajero/metabolismo , Fibroblastos/metabolismo , Hipoxia
18.
Cancer Med ; 12(14): 15632-15649, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37326348

RESUMEN

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.


Asunto(s)
Fosfofructoquinasas , Neoplasias del Cuello Uterino , Femenino , Humanos , Biomarcadores/metabolismo , Glucólisis/genética , L-Lactato Deshidrogenasa/genética , L-Lactato Deshidrogenasa/metabolismo , Lactato Deshidrogenasa 5/metabolismo , Fosfofructoquinasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Neoplasias del Cuello Uterino/genética
20.
HIV Med ; 24(9): 990-999, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37128161

RESUMEN

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.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Personas Transgénero , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Infecciones por VIH/epidemiología , Paraguay/epidemiología , Conducta Sexual , Factores de Riesgo , Prevalencia
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