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1.
Mol Divers ; 28(4): 1925-1945, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39097550

RESUMEN

Density Functional Theory (DFT) is extensively used in theoretical and computational chemistry to study molecular and crystal properties across diverse fields, including quantum chemistry, materials physics, catalysis, biochemistry, and surface science. Despite advances in DFT hardware and software for optimized geometries, achieving consensus in molecular structure comparisons with experimental counterparts remains a challenge. This difficulty is exacerbated by the lack of automated bond length comparison tools, resulting in labor-intensive and error-prone manual processes. To address these challenges, we propose MolGC, a Molecular Geometry Comparator algorithm that automates the comparison of optimized geometries from different theoretical levels. MolGC calculates the mean absolute error (MAE) of bond lengths by integrating data from various DFT software. It provides interactive and customizable visualization of geometries, enabling users to explore different views for enhanced analysis. In addition, it saves MAE computations for further analysis and offers a comprehensive statistical summary of the results. MolGC effectively addresses complex graph labeling challenges, ensuring accurate identification and categorization of bonds in diverse chemical structures. It achieves a 98.91% average rate in correct bond label assignments on an antibiotics dataset, showcasing its effectiveness for comparing molecular bond lengths across geometries of varying complexity and size. The executable file and software resources for running MolGC can be downloaded from https://github.com/AbimaelGP/MolGC/tree/main .


Asunto(s)
Algoritmos , Programas Informáticos , Teoría Funcional de la Densidad , Modelos Moleculares , Estructura Molecular
2.
Neuroradiology ; 66(11): 1955-1966, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39190159

RESUMEN

INTRODUCTION: Parkinson's disease (PD) is a neurodegenerative disorder characterized by dopaminergic neurons' degeneration of the substantia nigra, presenting with motor and non-motor symptoms. We hypothesized that altered diffusion metrics are associated with clinical symptoms in de novo PD patients. METHODS: Fractional Anisotropy (FA) and Mean (MD), Axial (AD), and Radial Diffusivity (RD) were assessed in 55 de novo PD patients (58.62 ± 9.85 years, 37 men) and 55 age-matched healthy controls (59.92 ± 11.25 years, 34 men). Diffusion-weighted images and clinical variables were collected from the Parkinson's Progression Markers Initiative study. Tract-based spatial statistics were used to identify white matter (WM) changes, and fiber tracts were localized using the JHU-WM tractography atlas. Motor and non-motor symptoms were evaluated in patients. RESULTS: We observed higher FA values and lower RD values in patients than controls in various fiber tracts (p-TFCE < 0.05). No significant MD or AD difference was observed between groups. Diffusion metrics of several regions significantly correlated with non-motor (state and trait anxiety and daytime sleepiness) and axial motor symptoms in the de novo PD group. No correlations were observed between diffusion metrics and other clinical symptoms evaluated. CONCLUSION: Our findings suggest microstructural changes in de novo PD fiber tracts; however, limited associations with clinical symptoms reveal the complexity of PD pathology. They may contribute to understanding the neurobiological changes underlying PD and have implications for developing targeted interventions. However, further longitudinal research with larger cohorts and consideration of confounding factors are necessary to elucidate the underlying mechanisms of these diffusion alterations in de novo PD.


Asunto(s)
Imagen de Difusión Tensora , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/diagnóstico por imagen , Masculino , Femenino , Persona de Mediana Edad , Imagen de Difusión Tensora/métodos , Estudios de Casos y Controles , Anisotropía , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Anciano
3.
J Anim Ecol ; 93(10): 1429-1441, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38953244

RESUMEN

Taylor's power law (TPL) describes the expected range of parameters of the mean-variance scaling relationship and has been extensively used in studies examining temporal variations in abundance. Few studies though have focused on biological and ecological covariates of TPL, while its statistical inherences have been extensively debated. In the present study, we focused on species-specific features (i.e. functional traits) that could be influential to temporal TPL. We combined field surveys of 180 fish species from 972 sites varying from small streams to large rivers with data on 31 ecological traits describing species-specific characteristics related to three main niche dimensions (trophic ecology, life history, and habitat use). For each species, the parameters of temporal TPL (intercept and slope) were estimated from the log-log mean-variance relationships while controlling for spatial dependencies and biological covariates (species richness and evenness). Then, we investigated whether functional traits explained variations in TPL parameters. Differences in TPL parameters among species were explained mostly by life history and environmental determinants, especially TPL slope. Life history was the main determinant of differences in TPL parameters and thereby aggregation patterns, with traits related to body size being the most influential, thus showing a high contrast between small-sized species with short lifespans and large-bodied migratory fishes, even after controlling for phylogenetic resemblances. We found that life history traits, especially those related to body size, mostly affect TPL and, as such, can be determinants of temporal variability of fish populations. We also found that statistical effects and phylogenetic resemblances are embedded in mean-variance relationships for fish, and that environmental drivers can interact with ecological characteristics of species in determining temporal fluctuations in abundance.


Asunto(s)
Peces , Rasgos de la Historia de Vida , Animales , Peces/fisiología , Ecosistema , Especificidad de la Especie , Ríos , Modelos Biológicos , Agua Dulce
4.
ACS Nano ; 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39066712

RESUMEN

Due to their physical properties including high thermal stability, very low vapor pressure, and high microwave absorption, ionic liquids have attracted great attention as solvents for the synthesis of nanomaterials, being considered as greener alternatives to traditional solvents. While usual solvents often need additives like surfactants, polymers, or other ligands to avoid nanoparticle coalescence, some ionic liquids can stabilize nanoparticles in dispersion without any additive. In order to quantify how the ionic liquids can affect both the aggregation thermodynamics and kinetics, molecular dynamics simulations were performed to simulate the evolution of concentrated dispersions and to compute the potential of mean force between nanoparticles of both hydrophilic and hydrophobic natures in two imidazolium-based ionic liquids, which differ from each other by the length of the cation alkyl group. Depending on the nature of the nanoparticle, structured layers of the polar and apolar regions of the ionic liquid can be formed close to its surface, and those layers lead to activation barriers for dispersed particles to get in contact. If the alkyl group of the ionic liquid is long enough to lead to domain segregation between the ionic and apolar portions of the solvent, the layered structure around the particle becomes more structured and propagates several nanometers away from its surface. This leads to stronger barriers close to the contact and also multiple barriers at larger distances that result from the unfavorable superposition of solvent layers of opposing nature when the nanoparticles approach each other. Those long-range solvent-mediated forces not only provide kinetic stability to dispersions but also affect their dynamics and lead to a long-range ordering between dispersed particles that can be explored as a template for the synthesis of complex materials.

5.
Sci Rep ; 14(1): 17219, 2024 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-39060371

RESUMEN

Fire plays a key role in grasslands, determining the distribution and evolution of species and boundaries with neighboring ecosystems. Evidence of community-wide responses to fire is largely based on taxonomic and functional descriptors, while the phylogenetic dimension is overlooked. Here we evaluated how the taxonomic and phylogenetic structure of grassland plant communities responded to a time since fire (TSF) gradient. We sampled 12 communities in Southern Brazil under varying TSF and calculated taxonomic species richness (S) and dominance (D), phylogenetic diversity (PD), and mean phylogenetic distances (MPD). We used Structural Equation Models to test the relationships between the environmental gradient and community descriptors. Communities with longer TSF presented higher PD and MPD but lower species richness and increased taxonomic dominance. These sites were dominated by monocots, specifically C4 grasses, but also presented exclusive clades, whereas recently-burned sites presented lower taxonomic dominance and more species distributed in a wider variety of clades. Our results indicate that these scenarios are interchangeable and dependent on fire management. Fire adaptation was not constrained by phylogenetic relatedness, contrasting with previous findings for tropical savannahs and indicating that temperate and tropical non-forest ecosystems from South America respond differently to fire, possibly due to different evolutionary histories.


Asunto(s)
Biodiversidad , Incendios , Pradera , Filogenia , Brasil , Plantas/clasificación , Plantas/genética , Poaceae/genética , Poaceae/clasificación , Ecosistema
6.
Clin Transl Oncol ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856872

RESUMEN

OBJECTIVE: Various systemic inflammation response indexes (SIRI) have repeatedly been described as prognostic factors in ovarian cancer. They have not been validated in prospective trials and published results are sometimes contradictory. We aimed to explore their role in a cohort of patients diagnosed with stage III and IV ovarian cancer treated at our institution. METHODS: We retrospectively examined the prognostic influence of the neutrophil-to-lymphocyte ratio (NLR), the platelet-to-lymphocyte ratio (PLR), the monocyte-to-lymphocyte ratio (MLR), the red cell distribution width (RDW), and the mean platelet volume (MPV). RESULTS: A total of 77 patients were analyzed. NLR > 2.243 at diagnosis, NLR before primary surgery, MLR at diagnosis, PLR > 289.1 at diagnosis, and PLR at diagnosis were significant in univariate Cox regression for progression-free survival, but none of them retained their significance in the multivariate Cox regression analysis. For overall survival, NLR > = 2.53 at diagnosis, MLR > = 0.245 at diagnosis, and PLR > = 198.3 at diagnosis resulted significant in univariate COX regression; only PLR > = 198.3 at diagnosis retained its significance in the multivariate analysis. CONCLUSION: In our cohort, PLR > = 198.3 was an independent prognostic factor for worse OS. The definitive role of SIRI in ovarian cancer has not yet been established. If their value as prognostic factors could finally be established, they would become a simple and economical method to predict prognosis in patients with advanced ovarian cancer. Therefore, it is time to conduct prospective, multicenter studies with larger samples to definitively establish its role in ovarian cancer, if any.

7.
High Blood Press Cardiovasc Prev ; 31(3): 251-259, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38704794

RESUMEN

INTRODUCTION: A lower ability to buffer pulse pressure (PP) in the face of increasing mean arterial pressure (MAP) may underlie the disproportionate increase in systolic blood pressure (SBP) in women from young adulthood through middle-aged relative to men. AIM: To evaluate the contribution of MAP to the change in PP and pressure wave contour in men and women from young adulthood to middle age. METHODS: Central pressure waveform was obtained from radial artery applanation tonometry in 312 hypertensive patients between 16 to 49 years (134 women, mean age 35 ± 9 years), 185 of whom were on antihypertensive treatment. RESULTS: Higher MAP levels (≥ 100 mmHg) were significantly associated with higher brachial and central SBP (P < 0.001), PP (P < 0.001), incident wave (P = 0.005), AP (P < 0.001), and PWV (P < 0.001) compared to lower MAP levels. The relationship between MAP and brachial PP (P < 0.001), central PP (P < 0.001), incident wave (P < 0.001), and AP (P < 0.01), but not PWV, strengthens with age. The age-related increase in the contribution of MAP to brachial PP (P < 0.001), central PP (P < 0.001), and incident wave (P < 0.001) was more prominent in women than in men beginning in the fourth decade. In multiple regression analyses, MAP remained a significantly stronger predictor of central PP and incident wave in women than in men, independent of age, heart rate, and antihypertensive treatment. In turn, age remained a significantly stronger predictor of central PP and incident wave in women than in men, independent of MAP, heart rate, and antihypertensive treatment. CONCLUSIONS: Women of reproductive age showed a steeper increase in PP with increasing MAP, despite comparable increases in arterial stiffness in both sexes. The difference was driven by a greater contribution of MAP to the forward component of the pressure wave in women.


Asunto(s)
Antihipertensivos , Presión Arterial , Hipertensión , Análisis de la Onda del Pulso , Humanos , Femenino , Masculino , Persona de Mediana Edad , Adulto , Factores Sexuales , Factores de Edad , Adulto Joven , Hipertensión/fisiopatología , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Adolescente , Antihipertensivos/uso terapéutico , Rigidez Vascular , Manometría , Factores de Riesgo , Arteria Radial/fisiología , Estudios Transversales
8.
Am J Obstet Gynecol ; 231(4): 395-407.e4, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38460833

RESUMEN

OBJECTIVE: This study aimed to assess global trends in mean birthweights at term, as reported in peer-reviewed literature. DATA SOURCES: We electronically searched PubMed, Embase, and Web of Science up to September 2023, using combinations of the search terms: "birth weight"; "birth-weight"; "birthweight"; "trend". There were no restrictions based on language or geographic area. STUDY ELIGIBILITY CRITERIA: We included all ecological and observational studies reporting mean birthweight at term as a continuous numerical variable over time. METHODS: We assessed the quality of included studies using the Dufault and Klar checklist modified by Betran et al. Univariate and multivariate linear models were used to examine the effects of time (years) and geographical origins. Subgroup analyses focused on national data sources and on data collected from 1950 onward. RESULTS: Among 6447 reviewed articles, 29 met our criteria, reporting mean birthweight data from over 183 million infants worldwide. Most studies were hospital-based (48.3%), 44.8% used national data, and a minority used municipality, community, or regional data (6.9%). Geographically, North America (31.0%) had the highest representation, followed by Asia and Europe (27.6% each), and South America and Oceania (6.9% each). Our univariate linear regression model (Model 1) revealed a significant increase in mean birthweight at term over time (4.74 g/y; 95% confidence interval, 3.95-5.53; P<.001). Model 2, incorporating continental dummy variables into the first model, confirmed this trend (3.85 g/y; 95% confidence interval, 2.96-4.74; P<.001). Model 3, focusing on available national data, did not find a significant relationship. Model 4 narrowed its focus on records from 1950 onward, reporting a robust annual increase of 7.26 g/y (95% confidence interval, 6.19-8.33; P<.001). Model 5, adjusting for the number of participants included in each study, reported a conclusive mean term birthweight increase of 1.46 g/y (95% confidence interval, 0.74-2.18; P<.001). CONCLUSION: This systematic review of 29 studies shows an increase in term birthweights over time, particularly when considering data since 1950. Limitations include study quality variations, data source diversity, and data sparsity, underscoring the need for future research to use precise gestational age distinctions and predetermined time frames to gain a deeper understanding of this trend and its implications for maternal and child health.


Asunto(s)
Peso al Nacer , Salud Global , Femenino , Humanos , Recién Nacido , Embarazo , Asia/epidemiología , Europa (Continente)/epidemiología , Salud Global/estadística & datos numéricos , Modelos Lineales , América del Norte/epidemiología , Oceanía/epidemiología , América del Sur/epidemiología , Nacimiento a Término
9.
Cir Cir ; 92(1): 52-58, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38537226

RESUMEN

OBJECTIVE: This study aimed to evaluate the value of platelet activation markers in predicting preeclampsia and its severity. Preeclampsia is a serious pregnancy complication that affects 3-5% of pregnancies and can lead to significant morbidity and mortality for both the mother and the fetus. METHODS: The study included 99 patients diagnosed with preeclampsia and 60 healthy pregnant women as a control group. Platelet activation markers such as mean platelet volume (MPV), platelet distribution width (PDW), platelet count, and plateletcrit were evaluated along with other clinical parameters. RESULTS: The results of the study showed that platelet activation markers, particularly PDW and MPV, are valuable in the diagnosis and follow-up of preeclampsia. However, they are not sufficient to predict the severity of the disease. CONCLUSION: The study suggests that platelet activation markers could aid in predicting, diagnosing, and managing preeclampsia. However, further research is needed to determine the role of these markers in predicting the severity of the disease. The findings of this study could contribute to the development of more effective strategies for the prevention and management of preeclampsia, which could ultimately improve maternal and fetal outcomes.


OBJETIVO: El estudio tuvo como objetivo determinar el valor de los marcadores de activación plaquetaria en la predicción de la preeclampsia y su gravedad. MÉTODO: Se incluyeron 99 pacientes diagnosticadas con preeclampsia, incluyendo 36 casos graves, y un grupo control de 60 mujeres embarazadas sanas. Se evaluaron diversas variables, como el volumen plaquetario medio, el recuento de plaquetas, el hematocrito plaquetario y la amplitud de distribución plaquetaria. RESULTADOS: Los resultados mostraron que el volumen plaquetario medio y la amplitud de distribución plaquetaria son parámetros valiosos en el diagnóstico y seguimiento de la preeclampsia, aunque no son suficientes para predecir su gravedad. El análisis estadístico reveló que la edad, el volumen plaquetario medio, la amplitud de distribución plaquetaria, la semana de gestación y los puntajes de Apgar al primer y quinto minuto fueron significativamente diferentes en el grupo de preeclampsia en comparación con el grupo control. CONCLUSIONES: En conclusión, estos resultados sugieren que los marcadores de activación plaquetaria pueden ser útiles para el diagnóstico y seguimiento de la preeclampsia, y que el volumen plaquetario medio y la amplitud de distribución plaquetaria, por ser parámetros económicos y accesibles, podrían ayudar a predecir, diagnosticar y manejar esta complicación durante el embarazo.


Asunto(s)
Preeclampsia , Complicaciones del Embarazo , Humanos , Femenino , Embarazo , Preeclampsia/diagnóstico , Volúmen Plaquetario Medio , Activación Plaquetaria , Recuento de Plaquetas/métodos
10.
Mar Environ Res ; 197: 106457, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38519355

RESUMEN

Recent estimates of the size at first maturity (L50) of Sardinella brasiliensis showed contradictory results with a decreasing in the fish stock biomass encompassed by increasing values of L50. The methodological approach used hereby allowed to separate sardines classified in the virginal maturity stage from those categorized in the recovery stage, and ready for one next spawning event. This study evaluated the hypothesis of the existence of separated stocks experiencing distinct environmental conditions and fishing pressures which may have altered L50 estimates using a robust dataset based on biological samples collected along the entire species distribution area in the southeast-south Brazilian coast [Rio de Janeiro (RJ), São Paulo (SP), Paraná (PR), Santa Catarina (SC) and Rio Grande do Sul (RS)] between 2000 and 2018. A reclassification of the gonadal maturity stages provided a more realistic estimate of L50. Combining biological, reproductive, fishing data and the mean temperature of the catch (MTC), the leave-one-out classification correctly re-assigned individuals with an overall accuracy of 85% [100% (RJ), 45% (SP), 99% (PR), 99% (SC) and 82% (RS)]. The connectivity between the local populations of S. brasiliensis off RJ (23°S) and the southern populations is limited, contrasting to spatial structured semi-discrete population-units found between SP and RS (24°S-30°S). The northern extreme population-unit (RJ, 22°S-23°S) showed an expressive reduction of L50, and a negative correlation was detected between the increasing MTC values and the abundance of early maturing individuals and recruits of the species. Stock specific L50 estimates seemed to act as indicators of long term environmental fluctuations.


Asunto(s)
Explotaciones Pesqueras , Reproducción , Animales , Brasil , Gónadas , Peces , Océano Atlántico
11.
J Microsc ; 296(3): 184-198, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38420882

RESUMEN

Nowadays, the use of super-resolution microscopy (SRM) is increasing globally due to its potential application in several fields of life sciences. However, a detailed and comprehensive guide is necessary for understanding a single-frame image's resolution limit. This study was performed to provide information about the structural organisation of isolated cellulose fibres from garlic and agave wastes through fluorophore-based techniques and image analysis algorithms. Confocal microscopy provided overall information on the cellulose fibres' microstructure, while techniques such as total internal reflection fluorescence microscopy facilitated the study of the plant fibres' surface structures at a sub-micrometric scale. Furthermore, SIM and single-molecule localisation microscopy (SMLM) using the PALM reconstruction wizard can resolve the network of cellulose fibres at the nanometric level. In contrast, the mean shift super-resolution (MSSR) algorithm successfully determined nanometric structures from confocal microscopy images. Atomic force microscopy was used as a microscopy technique for measuring the size of the fibres. Similar fibre sizes to those evaluated with SIM and SMLM were found using the MSSR algorithm and AFM. However, the MSSR algorithm must be cautiously applied because the selection of thresholding parameters still depends on human visual perception. Therefore, this contribution provides a comparative study of SRM techniques and MSSR algorithm using cellulose fibres as reference material to evaluate the performance of a mathematical algorithm for image processing of bioimages at a nanometric scale. In addition, this work could act as a simple guide for improving the lateral resolution of single-frame fluorescence bioimages when SRM facilities are unavailable.


Asunto(s)
Algoritmos , Celulosa , Microscopía Confocal , Celulosa/química , Microscopía Confocal/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen Individual de Molécula/métodos , Microscopía de Fuerza Atómica/métodos , Microscopía Fluorescente/métodos , Ajo/química
12.
Anat Histol Embryol ; 53(1): e13011, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38230831

RESUMEN

This study aimed to evaluate radiographic and sonographic features, and histogram parameters based on grayscale ultrasound of the liver and spleen in healthy toco toucans. Fifteen adult toco toucans (Ramphastos toco), seven females and eight males, weighing approximately 650 g, were enrolled in the study. On the right lateral radiographic view, the liver was visualized in the midventral region of the coelomic cavity; ultrasonographically, the liver was located in the middle portion of the coelomic cavity in close relationship to the heart, and thoracic and abdominal air sacs. Two hepatic lobes were identified; the right lobe was larger than the left one. The spleen was visualized in 10 toco toucans on radiographs and only in eight toucans on ultrasound exams. The gallbladder was identified only on ultrasound. On the right lateral radiographic view, the spleen was visualized dorsal to the proventriculus and ventral to the lungs/air sacs as an oval shape. Ultrasonographically, the spleen was observed caudal to the liver, cranial to the proventriculus and craniodorsal to the ventriculus. There was no significant difference in spleen length for either radiographic or ultrasound measurements. The brightness intensity (BI) for mean gray level (G) and standard deviation of gray levels (SG ) in the liver were 101.315 (± 16.170) and 12.453 (± 2.616), respectively. Mean G and SG levels in the spleen were 63.940 (± 18.321) and 7.494 (± 3.595), respectively. In conclusion, the sonographic features and histogram parameters indicated that the liver is more echogenic and heterogeneous than the spleen, which must be considered for diagnosing alterations in these organs.


Asunto(s)
Abdomen , Bazo , Femenino , Masculino , Animales , Bazo/diagnóstico por imagen , Hígado/diagnóstico por imagen , Ultrasonografía/veterinaria , Corazón , Aves
13.
Ultrasound Obstet Gynecol ; 63(3): 350-357, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37774112

RESUMEN

OBJECTIVE: Pre-eclampsia (PE) is a serious complication of pregnancy associated with maternal and fetal morbidity and mortality. As current prediction models have limitations and may not be applicable in resource-limited settings, we aimed to develop a machine-learning (ML) algorithm that offers a potential solution for developing accurate and efficient first-trimester prediction of PE. METHODS: We conducted a prospective cohort study in Mexico City, Mexico to develop a first-trimester prediction model for preterm PE (pPE) using ML. Maternal characteristics and locally derived multiples of the median (MoM) values for mean arterial pressure, uterine artery pulsatility index and serum placental growth factor were used for variable selection. The dataset was split into training, validation and test sets. An elastic-net method was employed for predictor selection, and model performance was evaluated using area under the receiver-operating-characteristics curve (AUC) and detection rates (DR) at 10% false-positive rates (FPR). RESULTS: The final analysis included 3050 pregnant women, of whom 124 (4.07%) developed PE. The ML model showed good performance, with AUCs of 0.897, 0.963 and 0.778 for pPE, early-onset PE (ePE) and any type of PE (all-PE), respectively. The DRs at 10% FPR were 76.5%, 88.2% and 50.1% for pPE, ePE and all-PE, respectively. CONCLUSIONS: Our ML model demonstrated high accuracy in predicting pPE and ePE using first-trimester maternal characteristics and locally derived MoM. The model may provide an efficient and accessible tool for early prediction of PE, facilitating timely intervention and improved maternal and fetal outcome. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Eficiencia de un enfoque de aprendizaje automático para la predicción de la preeclampsia en un país de ingresos medios OBJETIVO: La preeclampsia (PE) es una complicación grave del embarazo asociada a morbilidad y mortalidad materna y del feto. Dado que los modelos de predicción actuales tienen limitaciones y pueden no ser aplicables en situaciones con recursos limitados, se propuso desarrollar un algoritmo de aprendizaje automático (AA) que ofrezca una solución con potencial para desarrollar una predicción precisa y eficiente de la PE en el primer trimestre. MÉTODOS: Se realizó un estudio de cohorte prospectivo en Ciudad de México para desarrollar un modelo de predicción de la PE pretérmino (PEp) en el primer trimestre utilizando AA. Para la selección de variables se utilizaron las características maternas y los múltiplos de la mediana (MdM) obtenidos localmente para la presión arterial media, el índice de pulsatilidad de la arteria uterina y el factor de crecimiento placentario sérico. El conjunto de datos se dividió en subconjuntos de datos de entrenamiento, de validación y de test estadístico. Se empleó un método de red elástica para la selección de predictores, y el rendimiento del modelo se evaluó mediante el área bajo la curva de características operativas del receptor (ABC) y las tasas de detección (TD) con tasas de falsos positivos (TFP) del 10%. RESULTADOS: El análisis final incluyó a 3050 mujeres embarazadas, de las cuales 124 (4,07%) desarrollaron PE. El modelo de AA mostró una buena eficiencia, con un ABC de 0,897, 0,963 y 0,778 para la PEp, la PE de aparición temprana (PEat) y cualquier tipo de PE (todas las PE), respectivamente. Las TD con TFP del 10% fueron del 76,5%, 88,2% y 50,1% para la PEp, PEat y todas las PE, respectivamente. CONCLUSIONES: Nuestro modelo de AA demostró una alta precisión en la predicción de la PEp y la PEat utilizando características maternas del primer trimestre y MdM calculados localmente. El modelo puede proporcionar una herramienta eficiente y accesible para la predicción temprana de la PE, facilitando la intervención oportuna y la mejora de los resultados maternos y del feto.


Asunto(s)
Preeclampsia , Recién Nacido , Embarazo , Femenino , Humanos , Preeclampsia/diagnóstico , Factor de Crecimiento Placentario , Estudios Prospectivos , Biomarcadores , Primer Trimestre del Embarazo
14.
Mol Pharm ; 21(1): 38-52, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37646561

RESUMEN

The cisplatin encapsulation into carbon nanohorns (CNH) is a promising nanoformulation to circumvent the drug dissipation and to specifically accumulate it in tumor sites. Herein, biased molecular dynamics simulations were used to analyze the transmembrane transport of the CNH loaded with cisplatin through a breast cancer cell membrane prototype. The simulations revealed a four-stage mechanism: approach, insertion, permeation, and internalization. Despite the lowest structural disturbance of the membrane provided by the nanocarrier, the average free energy barrier for the translocation was 55.2 kcal mol-1, suggesting that the passive process is kinetically unfavorable. In contrast, the free energy profiles revealed potential wells of -6.8 kcal mol-1 along the insertion stage in the polar heads region of the membrane, which might enhance the retention of the drug in tumor sites; therefore, the most likely cisplatin delivery mechanism should involve the adsorption and retention of CNH on the surface of cancer cells, allowing the loaded cisplatin be slowly released and passively transported through the cell membrane.


Asunto(s)
Neoplasias de la Mama , Cisplatino , Humanos , Femenino , Cisplatino/química , Carbono , Neoplasias de la Mama/tratamiento farmacológico , Transporte Biológico , Membrana Celular
15.
Neuroradiol J ; 37(1): 60-67, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37915211

RESUMEN

BACKGROUND: Multiple sclerosis (MS) is an important cause of acquired neurological disability in young adults, characterized by multicentric inflammation, demyelination, and axonal damage. OBJECTIVE: The objective is to investigate white matter (WM) damage progression in a Brazilian MS patient cohort, using diffusion tensor imaging (DTI) post-processed by tract-based spatial statistics (TBSS). METHODS: DTI scans were acquired from 76 MS patients and 37 sex-and-age matched controls. Patients were divided into three groups based on disease duration. DTI was performed along 30 non-collinear directions by using a 1.5T imager. For TBSS analysis, the WM skeleton was created, and a 5000 permutation-based inference with a threshold of p < .05 was used, to enable the identification of abnormalities in fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD). RESULTS: Decreased FA and increased RD, MD, and AD were seen in patients compared to controls and a decreased FA and increased MD and RD were seen, predominantly after the first 5 years of disease, when compared between groups. CONCLUSION: Progressive WM deterioration is seen over time with a more prominent pattern after 5 years of disease onset, providing evidence that the early years might be a window to optimize treatment and prevent disability.


Asunto(s)
Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Sustancia Blanca , Adulto Joven , Humanos , Sustancia Blanca/diagnóstico por imagen , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Brasil , Anisotropía , Encéfalo
16.
Anat Histol Embryol ; 53(1): e12996, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38018271

RESUMEN

This study aimed to describe sonographic features of the liver, gallbladder and hepatic histogram from grey-scale ultrasound in three species of healthy non-venomous snakes. Twenty-eight adult snakes were enrolled in the study, including 10 common boas (Boa constrictor), eight black-tailed pythons (Python molurus) and 10 rainbow boas (Epicrates crassus). The snakes fasted for 30 days and were manually restrained while conscious. For B. constrictor and P. molurus the liver and gallbladder were best visualized in ventral recumbency, and E. crassus in dorsal recumbency. A single elongated hepatic lobe was identified in all snakes. The gallbladder was positioned caudal and separated from the liver, with an oval shape and homogeneous anechoic content in the lumen, and thin and regular walls. A region of interest by pixel number was chosen for the liver, fat bodies, left kidney, and splenopancreas. The mean grey level (G) of the organs had significant differences within each species. Standard deviation of grey levels (SG ) had significant differences within B. constrictor and E. crassus. P. molurus had no significant difference among organs. The comparison among snakes showed that E. crassus had G of liver and splenopancreas lower than B. constrictor and P. molurus. The SG of the liver in E. crassus was lowest compared to B. constrictor and P. molurus. P. molurus showed the highest values in mean of G and SG . In conclusion, despite the liver and gallbladder having similar sonographic features, the grey-level histogram showed that liver echotexture and echogenicity differ among species.


Asunto(s)
Boidae , Vesícula Biliar , Animales , Vesícula Biliar/diagnóstico por imagen , Hígado/diagnóstico por imagen , Riñón , Serpientes
17.
Rev. Paul. Pediatr. (Ed. Port., Online) ; 42: e2023016, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1521605

RESUMEN

ABSTRACT Objective: To examine the neutrophil-lymphocyte ratio, red cell distribution width and mean platelet volume in patients with febrile seizure and to determine their role in febrile seizure classification. Methods: This was a retrospective hospital-based study conducted among patients aged 5 to 72 months admitted with febrile seizure. Children who had febrile seizures due to upper respiratory tract infection were included in the study. The children were divided into two groups: simple febrile seizures and complex febrile seizures. Patients with a history of febrile status epilepticus, previous convulsions, use of antiepileptic or other chronic drugs, foci of infection other than the upper respiratory tract infection, abnormal biochemical parameters, and chronic mental or physical disease were excluded from the study. Clinical and laboratory findings of the patients were obtained from digital medical records. Results: The records of 112 febrile seizure patients were reviewed, and 89 were grouped as simple and 23 as complex febrile seizures. Although there was no statistically significant difference between the two groups in terms of the mean red cell distribution width values (p=0.703), neutrophil-lymphocyte ratio and mean platelet volume were significantly higher in patients with complex febrile seizures (p=0.034, p=0.037; respectively). Conclusions: This study showed that neutrophil-lymphocyte ratio and mean platelet volume could be practical and inexpensive clinical markers for febrile seizure classification. A similar result could not be reached for red cell distribution width in this study. These findings should be supported by multicenter studies with large samples.


RESUMO Objetivo: Examinar a relação linfócitos-neutrófilos, amplitude de distribuição de hemácias e volume médio de plaquetas em pacientes com convulsão febril, e determinar seu papel na classificação de convulsão febril. Métodos: Este foi um estudo retrospectivo de base hospitalar realizado com pacientes de 5 a 72 meses admitidos com convulsão febril. Crianças que tiveram convulsões febris em razão de infecção do trato respiratório superior foram incluídas no estudo. As crianças foram divididas em dois grupos: convulsões febris simples e complexas. Pacientes com história de Status epiléptico febril, convulsões prévias, uso de drogas antiepilépticas ou outras drogas crônicas, com focos de infecção que não a do trato respiratório superior, parâmetros bioquímicos anormais e doenças crônicas mentais ou físicas foram excluídos do estudo. Os achados clínicos e laboratoriais dos pacientes foram obtidos a partir dos prontuários médicos digitais. Resultados: Registros de 112 pacientes com convulsão febril foram revisados: 89 com convulsões febris simples e 23 com complexas. Embora não tenha havido diferença estatisticamente significativa entre os dois grupos em termos de valor médio de amplitude de distribuição de hemácias (p=0,703), a relação linfócitos-neutrófilos e o volume médio de plaquetas foram significativamente mais elevados em pacientes com convulsões febris simples (p=0,034, p=0,037; respectivamente). Conclusões: Este estudo mostrou que a relação linfócitos-neutrófilos e o volume médio de plaquetas podem ser marcadores clínicos práticos e de baixo custo para a classificação de convulsão febril. Um resultado semelhante não pôde ser alcançado para a amplitude de distribuição de hemácias neste estudo. Esses achados devem ser apoiados por estudos multicêntricos com grandes amostras.

18.
Clinics (Sao Paulo) ; 78: 100308, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38041986

RESUMEN

OBJECTIVES: Traumatic hemorrhagic shock is a major death-related factor contributing to mortality in emergencies and can be effectively handled by the Limited Fluid Resuscitation (LFR) method. In the current investigation, the authors analyzed the influence of different administrating blood pressure on the treatment outcomes of LFR. METHODS: 276 participants were enrolled in the current study retrospectively from January 2016 to December 2021 and were divided into three groups based on the administrating blood pressure of LFR. The difference among the three groups regarding serum levels of cytokines as well as blood hemodynamics parameters was analyzed. RESULTS: The results showed after the T2 stage treatment, cytokine levels in the three groups were all significantly influenced by different LFR strategies with medium MAP showing the strongest effects on the expression of all cytokine genes. Moreover, the MAP value was in positive correlation with IL-6, IL-10, and TNF-α levels, but showed no clear relation with IL-4 level in all three groups. Regarding the effects on hemodynamics parameters, the levels of CVP, CO, and CI were slightly increased by the different LFR administrating strategies, and the effect of medium and high MAP was statistically stronger than that of low MAP. CONCLUSION: The present results showed that LFR would influence serum inflammatory levels by improving blood hemodynamics parameters. Medium MAP showed the strongest improving effects with the least side effects, which can be employed as the optimal administrating strategy for LFR in the future.


Asunto(s)
Choque Hemorrágico , Humanos , Choque Hemorrágico/terapia , Estudios Retrospectivos , Hemodinámica , Citocinas , Resultado del Tratamiento , Fluidoterapia/métodos , Resucitación/métodos
19.
Front Plant Sci ; 14: 1276424, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38023915

RESUMEN

Wood density (WD) is a key functional trait related to ecological strategies and ecosystem carbon dynamics. Despite its importance, there is a considerable lack of information on WD in tropical Andean forests, particularly regarding its relationship with forest succession and ecosystem carbon cycling. Here, we quantified WD in 86 upper Andean tree and shrub species in central Colombia, with the aim of determining how WD changes with forest succession and how it is related to productivity. We hypothesized that WD will increase with succession because early successional forests will be colonized by acquisitive species, which typically have low WD, while the shaded understory of older forests should favor higher WD. We measured WD in 481 individuals from 27 shrub and 59 tree species, and quantified aboveground biomass (AGB), canopy height, net primary production (NPP) and species composition and abundance in 14, 400-m2, permanent plots. Mean WD was 0.513 ± 0.114 (g/cm3), with a range between 0.068 and 0.718 (g/cm3). Shrubs had, on average, higher WD (0.552 ± 0.095 g/cm3) than trees (0.488 ± 0.104 g/cm3). Community weighted mean WD (CWMwd) decreased with succession (measured as mean canopy height, AGB, and basal area); CWMwd also decreased with aboveground NPP and stem growth. In contrast, the percentage of NPP attributed to litter and the percent of shrubs in plots increased with CWMwd. Thus, our hypothesis was not supported because early successional forests had higher CWMwd than late successional forests. This was related to a high proportion of shrubs (with high WD) early in succession, which could be a consequence of: 1) a low seed availability of trees due to intense land use in the landscape and/or 2) harsh abiotic conditions early in succession that filter out trees. Forest with high CWMwd had a high %NPP attributed to litter because they were dominated by shrubs, which gain little biomass in their trunks. Our findings highlight the links between WD, succession and carbon cycling (biomass and productivity) in this biodiversity hotspot. Thus, WD is an important trait that can be used to understand upper Andean forest recovery and improve forest restoration and management practices.

20.
Entropy (Basel) ; 25(11)2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37998168

RESUMEN

The security of a network requires the correct identification and characterization of the attacks through its ports. This involves the follow-up of all the requests for access to the networks by all kinds of users. We consider the frequency of connections and the type of connections to a network, and determine their joint probability. This leads to the problem of determining a joint probability distribution from the knowledge of its marginals in the presence of errors of measurement. Mathematically, this consists of an ill-posed linear problem with convex constraints, which we solved by the method of maximum entropy in the mean. This procedure is flexible enough to accommodate errors in the data in a natural way. Also, the procedure is model-free and, hence, it does not require fitting unknown parameters.

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