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1.
Sensors (Basel) ; 24(5)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38474892

RESUMEN

This paper describes the design and optimization of a smart algorithm based on artificial intelligence to increase the accuracy of an ocean water current meter. The main purpose of water current meters is to obtain the fundamental frequency of the ocean waves and currents. The limiting factor in those underwater applications is power consumption and that is the reason to use only ultra-low power microcontrollers. On the other hand, nowadays extraction algorithms assume that the processed signal is defined in a fixed bandwidth. In our approach, belonging to the edge computing research area, we use a deep neural network to determine the narrow bandwidth for filtering the fundamental frequency of the ocean waves and currents on board instruments. The proposed solution is implemented on an 8 MHz ARM Cortex-M0+ microcontroller without a floating point unit requiring only 9.54 ms in the worst case based on a deep neural network solution. Compared to a greedy algorithm in terms of computational effort, our worst-case approach is 1.81 times faster than a fast Fourier transform with a length of 32 samples. The proposed solution is 2.33 times better when an artificial neural network approach is adopted.

2.
J Membr Biol ; 256(3): 271-285, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37140614

RESUMEN

The main objective of the present study was to find detergents that can maintain the functionality and stability of the Torpedo californica nicotinic acetylcholine receptor (Tc-nAChR). We examined the functionality, stability, and purity analysis of affinity-purified Tc-nAChR solubilized in detergents from the Cyclofos (CF) family [cyclofoscholine 4 (CF-4), cyclofoscholine 6 (CF-6), and cyclofloscholine 7 (CF-7)]. The functionality of the CF-Tc-nAChR-detergent complex (DC) was evaluated using the Two Electrode Voltage Clamp (TEVC) method. To assess stability, we used the florescence recovery after photobleaching (FRAP) in Lipidic Cubic Phase (LCP) methodology. We also performed a lipidomic analysis using Ultra-Performance Liquid Chromatography (UPLC) coupled to electrospray ionization mass spectrometry (ESI-MS/MS) to evaluate the lipid composition of the CF-Tc-nAChR-DCs. The CF-4-Tc-nAChR-DC displayed a robust macroscopic current (- 200 ± 60 nA); however, the CF-6-Tc-nAChR-DC and CF-7-Tc-nAChR-DC displayed significant reductions in the macroscopic currents. The CF-6-Tc-nAChR and CF-4-Tc-nAChR displayed higher fractional florescence recovery. Addition of cholesterol produced a mild enhancement of the mobile fraction on the CF-6-Tc-nAChR. The lipidomic analysis revealed that the CF-7-Tc-nAChR-DC displayed substantial delipidation, consistent with the lack of stability and functional response of this complex. Although the CF-6-nAChR-DC complex retained the largest amount of lipids, it showed a loss of six lipid species [SM(d16:1/18:0); PC(18:2/14:1); PC(14:0/18:1); PC(16:0/18:1); PC(20:5/20:4), and PC(20:4/20:5)] that are present in the CF-4-nAChR-DC. Overall, the CF-4-nAChR displayed robust functionality, significant stability, and the best purity among the three CF detergents; therefore, CF-4 is a suitable candidate to prepare Tc-nAChR crystals for structural studies.


Asunto(s)
Detergentes , Receptores Nicotínicos , Animales , Espectrometría de Masas en Tándem , Torpedo , Receptores Nicotínicos/química , Lípidos/química , Electrofisiología
3.
Sensors (Basel) ; 23(14)2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37514843

RESUMEN

Underwater sensor networks play a crucial role in collecting valuable data to monitor offshore aquaculture infrastructures. The number of deployed devices not only impacts the bandwidth for a highly constrained communication environment, but also the cost of the sensor network. On the other hand, industrial and literature current meters work as raw data loggers, and most of the calculations to determine the fundamental frequencies are performed offline on a desktop computer or in the cloud. Belonging to the edge computing research area, this paper presents an algorithm to extract the fundamental frequencies of water currents in an underwater sensor network deployed in offshore aquaculture infrastructures. The target sensor node is based on a commercial ultra-low-power microcontroller. The proposed fundamental frequency identification algorithm only requires the use of an integer arithmetic unit. Our approach exploits the mathematical properties of the finite impulse response (FIR) filtering in the integer domain. The design and implementation of the presented algorithm are discussed in detail in terms of FIR tuning/coefficient selection, memory usage and variable domain for its mathematical formulation aimed at reducing the computational effort required. The approach is validated using a shallow water current model and real-world raw data from an offshore aquaculture infrastructure. The extracted frequencies have a maximum error below a 4%.

4.
Int J Mol Sci ; 24(16)2023 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-37629165

RESUMEN

The pathogenesis of obesity-related-renal disease is unknown. Menopause can promote renal disease in obese women, but this interaction is unclear. In a previous study, we observed that obese male and female mice developed albuminuria, hyperfiltration, and glomerulomegaly, and these changes were more severe in those obese ovariectomized females. In this study, we also evaluated renal inflammation and lipotoxicity in that animal model. For six months, 43 males and 36 females C57BL6/J mice were randomized to standard diet (SD) or high fat diet (HFD). A group of female animals on SD or HFD was ovariectomized to simulate menopause. We evaluated cytokines: NF-κß p65, IL-1ß, MCP-1, TNF-α, total lipid content, lipid classes, and fatty acid profile in total lipid and individual lipid classes in renal tissue and urine. We found that obese males and females showed higher NF-kß p-65, TNF-α and MCP-1 in renal tissue, and obese females ovariectomized had higher IL-1ß and TNF-α compared with not-ovariectomized. Also, obese animals showed lower proinflammatory and higher anti-inflammatory fatty acids in kidney total lipids, while obese females ovariectomized had a more exacerbated pattern. In brief, obesity induces inflammation and an unbalanced lipidic profile in renal tissue. This pattern seems to be enhanced in obesity after menopause.


Asunto(s)
Enfermedades Renales , Nefritis , Obesidad , Animales , Femenino , Masculino , Ratones , Ácidos Grasos , Inflamación , Menopausia , Factores Sexuales , Factor de Necrosis Tumoral alfa , Distribución Aleatoria , Modelos Animales de Enfermedad
5.
Part Fibre Toxicol ; 18(1): 41, 2021 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-34809667

RESUMEN

BACKGROUND: Engineered stone silicosis is an emerging disease in many countries worldwide produced by the inhalation of respirable dust of engineered stone. This silicosis has a high incidence among young workers, with a short latency period and greater aggressiveness than silicosis caused by natural materials. Although the silica content is very high and this is the key factor, it has been postulated that other constituents in engineered stones can influence the aggressiveness of the disease. Different samples of engineered stone countertops (fabricated by workers during the years prior to their diagnoses), as well as seven lung samples from exposed patients, were analyzed by multiple techniques. RESULTS: The different countertops were composed of SiO2 in percentages between 87.9 and 99.6%, with variable relationships of quartz and cristobalite depending on the sample. The most abundant metals were Al, Na, Fe, Ca and Ti. The most frequent volatile organic compounds were styrene, toluene and m-xylene, and among the polycyclic aromatic hydrocarbons, phenanthrene and naphthalene were detected in all samples. Patients were all males, between 26 and 46 years-old (average age: 36) at the moment of the diagnosis. They were exposed to the engineered stone an average time of 14 years. At diagnosis, only one patient had progressive massive fibrosis. After a follow-up period of 8 ± 3 years, four patients presented progressive massive fibrosis. Samples obtained from lung biopsies most frequently showed well or ill-defined nodules, composed of histiocytic cells and fibroblasts without central hyalinization. All tissue samples showed high proportion of Si and Al at the center of the nodules, becoming sparser at the periphery. Al to Si content ratios turned out to be higher than 1 in two of the studied cases. Correlation between Si and Al was very high (r = 0.93). CONCLUSION: Some of the volatile organic compounds, polycyclic aromatic hydrocarbons and metals detected in the studied countertop samples have been described as causative of lung inflammation and respiratory disease. Among inorganic constituents, aluminum has been a relevant component within the silicotic nodule, reaching atomic concentrations even higher than silicon in some cases. Such concentrations, both for silicon and aluminum showed a decreasing tendency from the center of the nodule towards its frontier.


Asunto(s)
Exposición Profesional , Silicosis , Adulto , Polvo , Humanos , Masculino , Persona de Mediana Edad , Exposición Profesional/efectos adversos , Exposición Profesional/análisis , Cuarzo , Dióxido de Silicio
6.
Fetal Diagn Ther ; 48(7): 551-559, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34407539

RESUMEN

OBJECTIVE: The aim of the study was to determine if customized fetal growth charts developed excluding obese and underweight mothers (CC(18.5-25)) are better than customized curves (CC) at identifying pregnancies at risk of perinatal morbidity. MATERIAL AND METHODS: Data from 20,331 infants were used to construct CC and from 11,604 for CC(18.5-25), after excluding the cases with abnormal maternal BMI. The 2 models were applied to 27,507 newborns and the perinatal outcomes were compared between large for gestational age (LGA) or small for gestational age (SGA) according to each model. Logistic regression was used to calculate the OR of outcomes by the group, with gestational age (GA) as covariable. The confidence intervals of pH were calculated by analysis of covariance. RESULTS: The rate of cesarean and cephalopelvic disproportion (CPD) were higher in LGAonly by CC(18.5-25) than in LGAonly by CC. In SGAonly by CC(18.5-25), neonatal intensive care unit (NICU) and perinatal mortality rates were higher than in SGAonly by CC. Adverse outcomes rate was higher in LGAonly by CC(18.5-25) than in LGAonly by CC (21.6%; OR = 1.61, [1.34-193]) vs. (13.5%; OR = 0.84, [0.66-1.07]), and in SGA only by CC(18.5-25) than in SGAonly by CC (9.6%; OR = 1.62, [1.25-2.10] vs. 6.3%; OR = 1.18, [0.85-1.66]). CONCLUSION: The use of CC(18.5-25) allows a more accurate identification of LGA and SGA infants at risk of perinatal morbidity than conventional CC. This benefit increase and decrease, respectively, with GA.


Asunto(s)
Peso Fetal , Delgadez , Peso al Nacer , Femenino , Gráficos de Crecimiento , Humanos , Lactante , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Obesidad/epidemiología , Embarazo , Estudios Retrospectivos
7.
Pediatr Res ; 88(1): 91-99, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31822017

RESUMEN

BACKGROUND: Delayed brain function development in small-gestational-age (SGA) infants has been reported. We aimed to quantify rates of immature neonatal EEG patterns and their association with neurodevelopment in SGA full-term neonates. METHODS: Using a cohort design, 50 SGA (birthweight <10th percentile) and 44 appropriate-gestational-age (AGA) term neonates underwent continuous video-EEG recordings lasting >3 h. Seventy-three of them were assessed at 2-years-old using Bayley-III-Scales. For EEG analysis, several segments of discontinuous/alternating EEG tracings were selected. MAIN OUTCOMES MEASURED: (1) Visual analysis (patterns of EEG maturity); (2) Power spectrum in δ, θ, α and ß frequency bands; and (3) scores in motor, cognitive and language development. RESULTS: (1) SGA infants, compared to AGA, showed: (a) higher percentages of discontinuous EEG, both asynchrony and interhemispheric asymmetry, and bursts with delta-brushes, longer interburst-interval duration and more transients/hour; (b) lower relative power spectrum in δ and higher in α; and (c) lower scores on motor, language and cognitive neurodevelopment. (2) Asymmetry >5%, interburst-interval >5 s, discontinuity >11%, and bursts with delta-brushes >11% were associated with lower scores on Bayley-III. CONCLUSIONS: In this prospective study, SGA full-term neonates showed high rates of immature EEG patterns. Low-birthweight and immaturity EEG were both correlated with low development scores.


Asunto(s)
Electroencefalografía/métodos , Retardo del Crecimiento Fetal/fisiopatología , Recién Nacido Pequeño para la Edad Gestacional , Peso al Nacer , Encéfalo/fisiopatología , Desarrollo Infantil , Estudios de Cohortes , Femenino , Retardo del Crecimiento Fetal/diagnóstico , Edad Gestacional , Humanos , Recién Nacido , Masculino , Pronóstico , Estudios Prospectivos , Visión Ocular
8.
Lupus ; 29(7): 761-766, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32362181

RESUMEN

INTRODUCTION: Lupus erythematosus (LE) is an autoimmune disease often treated with antimalarial drugs. The prolonged use of chloroquine and hydroxychloroquine can cause hyperpigmentation in the skin, oral mucosa and retinal pigment epithelium, which in turn can trigger toxicity in this epithelium, which in some cases causes vision loss. The objective of the present work was to establish the association between the presence of oral pigmented macules by antimalarial and secondary retinal toxicity. METHODS: A total of 105 patients diagnosed with LE being treated with chloroquine/hydroxychloroquine were evaluated. All patients were ophthalmologically evaluated for retinopathy screening. When the patient showed oral hyperpigmented maculae, an incisional biopsy was performed with the corresponding histopathological study with informed consent. The variables were compared using the chi-square test for quantitative variables and the non-parametric Mann-Whitney U-test for categorical variables. The confidence level was established at 95%, and p-values of ≤0.005 were considered statistically significant. RESULTS: Only 9.5% of the patients showed oral brown spots. Histopathologically, 100% of the oral macules showed characteristics of oral pigmentation by drug and 100% ophthalmological parameters of normality. Two patients presented with a diagnosis of pre-retinopathy, but none showed oral lesions. CONCLUSION: Hyperpigmented macules in the buccal mucosa in lupus patients receiving antimalarial treatment are not frequent and do not represent a predictive finding of toxicity of the drug.


Asunto(s)
Cloroquina/efectos adversos , Hidroxicloroquina/efectos adversos , Hiperpigmentación/inducido químicamente , Lupus Eritematoso Sistémico/tratamiento farmacológico , Enfermedades de la Retina/inducido químicamente , Adolescente , Adulto , Anciano , Antimaláricos/administración & dosificación , Antimaláricos/efectos adversos , Cloroquina/administración & dosificación , Femenino , Humanos , Hidroxicloroquina/administración & dosificación , Masculino , Persona de Mediana Edad , Mucosa Bucal/patología , Factores de Riesgo , Venezuela , Adulto Joven
9.
Angew Chem Int Ed Engl ; 58(22): 7324-7328, 2019 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-30891840

RESUMEN

The P and M enantiomers of the octanuclear [Fe8 (µ4 -O)4 (µ-4-Cl-pz)12 Cl4 ] complex, having T symmetry, were resolved by temporary substitution of chloride ligands by racemic 4-s Bu-phenolates and subsequent crystallization, where the (S)- and (R)-phenolates coordinate selectively to the M and P complexes, respectively. The complexes were characterized by circular dichroism analysis and X-ray structure determination. This work constitutes a rare example of enantiomeric recognition resulting in spontaneous resolution upon crystallization.

10.
Pediatr Res ; 84(4): 564-567, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29991774

RESUMEN

OBJECTIVE: The aim of this study is to gain insights into the role of visceral adipose tissue as a source of C-reactive protein (CRP) in acute inflammation and to explore the potential relationship of CRP expression with the severity of appendicitis. METHODS: A total of 20 pediatric patients undergoing appendectomy were included in the study. Patients were divided into two groups according to appendicitis severity (uncomplicated and complicated). CRP levels were measured in visceral fat samples by western blotting, as well as in serum by biochemical testing. RESULTS: CRP was found to be expressed in visceral adipose tissue. The adipose tissue of patients with complicated appendicitis showed significantly higher CRP levels (p = 0.002) compared to patients with uncomplicated appendicitis. These results mirrored the CRP values obtained in serum (p = 0.018). CONCLUSION: In childhood, visceral adipose tissue is a source of CRP in acute inflammation, and its expression is potentially associated with the severity of local inflammation.


Asunto(s)
Apendicitis/sangre , Proteína C-Reactiva/análisis , Inflamación/metabolismo , Grasa Intraabdominal/metabolismo , Enfermedad Aguda , Apendicectomía , Biomarcadores/sangre , Niño , Femenino , Regulación de la Expresión Génica , Humanos , Recuento de Leucocitos , Masculino
11.
Fetal Diagn Ther ; 44(4): 256-263, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29393218

RESUMEN

INTRODUCTION: We evaluated the utility of placental volume and three-dimensional (3D) vascular flow indices to predict early and late preeclampsia. MATERIAL AND METHODS: In 1,004 pregnancies attending routine care, we recorded first-trimester screening program for aneuploidy (FTSA) parameter and measured uterine artery pulsatility index (uterine-a PI). Placental volume and vascular flow indices were obtained using 3D power Doppler and VOCAL techniques. RESULTS: Placental volume was lower and uterine-a PI was higher in both early and late preeclampsia groups versus nonaffected pregnancies. The prediction rate of placental volume in late preeclampsia was higher than that of uterine-a PI (AUROC 0.707 vs. 0.581, p < 0.011). The inclusion of placental volume improved significantly the prediction rate of total and late preeclampsia in the models constructed with maternal characteristics, FTSA, and uterine-a PI (AUROC 0.745 vs. 0.818, p < 0.004, and 0.740 vs. 0.812, p < 0.012, respectively). The inclusion of vascular indices did not improve the predictive value of these models. DISCUSSION: Placental volume was an independent predictor of total, early, and late preeclampsia and its inclusion in combined predictive models significantly improved prediction rates. Reduced placental volume observed at first trimester in women with early and late preeclampsia suggests that these entities are the clinical expression of a similar pathophysiological process.


Asunto(s)
Placenta/diagnóstico por imagen , Circulación Placentaria , Preeclampsia/diagnóstico , Primer Trimestre del Embarazo , Estudios de Cohortes , Femenino , Humanos , Placenta/irrigación sanguínea , Valor Predictivo de las Pruebas , Embarazo , Resultado del Embarazo
12.
Biochim Biophys Acta ; 1858(1): 47-56, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26454038

RESUMEN

In our previous study we examined the functionality and stability of nicotinic acetylcholine receptor (nAChR)-detergent complexes (nAChR-DCs) from affinity-purified Torpedo californica (Tc) using fluorescence recovery after photobleaching (FRAP) in Lipidic Cubic Phase (LCP) and planar lipid bilayer (PLB) recordings for phospholipid and cholesterol like detergents. In the present study we enhanced the functional characterization of nAChR-DCs by recording macroscopic ion channel currents in Xenopus oocytes using the two electrode voltage clamp (TEVC). The use of TEVC allows for the recording of macroscopic currents elicited by agonist activation of nAChR-DCs that assemble in the oocyte plasma membrane. Furthermore, we examined the stability of nAChR-DCs, which is obligatory for the nAChR crystallization, using a 30 day FRAP assay in LCP for each detergent. The present results indicate a marked difference in the fractional fluorescence recovery (ΔFFR) within the same detergent family during the 30 day period assayed. Within the cholesterol analog family, sodium cholate and CHAPSO displayed a minimum ΔFFR and a mobile fraction (MF) over 80%. In contrast, CHAPS and BigCHAP showed a marked decay in both the mobile fraction and diffusion coefficient. nAChR-DCs containing phospholipid analog detergents with an alkylphosphocholine (FC) and lysofoscholine (LFC) of 16 carbon chains (FC-16, LFC-16) were more effective in maintaining a mobile fraction of over 80% compared to their counterparts with shorter acyl chain (C12, C14). The significant differences in macroscopic current amplitudes, activation and desensitization rates among the different nAChR-DCs evaluated in the present study allow to dissect which detergent preserves both, agonist activation and ion channel function. Functionality assays using TEVC demonstrated that LFC16, LFC14, and cholate were the most effective detergents in preserving macroscopic ion channel function, however, the nAChR-cholate complex display a significant delay in the ACh-induce channel activation. In summary, these results suggest that the physical properties of the lipid analog detergents (headgroup and acyl chain length) are the most effective in maintaining both the stability and functionality of the nAChR in the detergent solubilized complex.


Asunto(s)
Detergentes/química , Membrana Dobles de Lípidos/química , Oocitos/fisiología , Fosfolípidos/química , Receptores Nicotínicos/química , Torpedo/metabolismo , Animales , Membrana Celular/química , Membrana Celular/fisiología , Colesterol/química , Ácidos Cólicos/química , Cristalización , Detergentes/clasificación , Potenciales Evocados/fisiología , Recuperación de Fluorescencia tras Fotoblanqueo , Microinyecciones , Oocitos/química , Técnicas de Placa-Clamp , Unión Proteica , Estabilidad Proteica , Receptores Nicotínicos/aislamiento & purificación , Receptores Nicotínicos/fisiología , Colato de Sodio/química , Relación Estructura-Actividad , Termodinámica , Xenopus laevis/metabolismo
13.
J Anat ; 230(1): 66-74, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27485947

RESUMEN

The methodology for sex determination in human skeletal remains depends on the different bone morphologies presented by men and women. Due to their direct implications in reproduction, the whole pelvis, particularly the os coxae, shows different characteristics in either sex. The sacrum and the os coxae constitute the birth canal. In this research study, the os coxae shape is analyzed using geometric morphometrics, providing information on morphology, regardless of size or any other factor beyond the geometry itself. A total of 46 adult ossa coxae from a Spanish archaeological collection were studied using geometric morphometrics. The results show that there is a restriction on the shape of female os coxae. In contrast, male os coxae presents a greater range of variation. The biological reason for this difference is the obstetrical dilemma; a concept defined as the anatomical conflict between bipedalism and the full-term birth of a neonate whose large head requires greater dimensions in the pelvic cavity. Our experimental data reinforce the validity of the obstetrical dilemma as source of the restriction on the shape of female ossa coxae. Additionally, according to the results obtained, size itself does not represent a condition for belonging to one sex or another.


Asunto(s)
Evolución Biológica , Huesos Pélvicos/anatomía & histología , Adulto , Femenino , Humanos , Análisis de Componente Principal/métodos
14.
J Pediatr Gastroenterol Nutr ; 64(4): 605-609, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28333827

RESUMEN

BACKGROUND: Evidence of silicon's importance to health has been gradually accumulating. Nevertheless, there are few studies comparing serum silicon levels in newborns with maternal levels. Likewise, little is known concerning the inter-relation between silicon and other trace elements. OBJECTIVE: The present study evaluated maternal and newborn levels of serum silicon and their relation to those of zinc and copper. METHODS: We measured serum silicon, copper, and zinc in 66 pregnant women, in the umbilical cord of their infants, and in 44 newborns, by atomic absorption spectrophotometry. All the samples were from fasted subjects. RESULTS: Serum silicon level in term newborns (20.6 ±â€Š13.2 µmol/L) was significantly higher than in umbilical cord (8.9 ±â€Š3.5 µmol/L; P < 0.0001). Mean serum silicon level in maternal vein (7.7 ±â€Š3.4 µmol/L) was lower than that in umbilical cord, although differences were not significant. We also found higher levels of zinc (P = 0.008) and lower levels of copper (P < 0.0001) in cord blood compared with maternal blood. Umbilical venous/maternal venous level ratios of zinc, copper, and silicon were 1.5 ±â€Š0.5, 0.2 ±â€Š0.1, and 1.3 ±â€Š0.7, respectively. There was a positive correlation between silicon and zinc levels (r = 0.32), and a negative correlation between copper and zinc levels (r = -0.35). CONCLUSIONS: It seems that there is a positive gradient of silicon from the mother to her fetus. Silicon levels were higher in newborn than in cord blood, and correlated significantly with that of zinc but not copper. Additional investigations are needed to further define the role of silicon and its interaction with other trace elements during the perinatal period.


Asunto(s)
Cobre/sangre , Fenómenos Fisiológicos Nutricionales del Lactante , Intercambio Materno-Fetal , Fenómenos Fisiologicos de la Nutrición Prenatal , Silicio/sangre , Oligoelementos/sangre , Zinc/sangre , Adulto , Biomarcadores/sangre , Estudios Transversales , Femenino , Sangre Fetal/metabolismo , Humanos , Recién Nacido , Masculino , Embarazo , Espectrofotometría Atómica
15.
Prenat Diagn ; 35(12): 1247-54, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26395429

RESUMEN

OBJECTIVE: To analyze placental volume and vascularization at first trimester in women with pre-eclampsia, and secondarily, the effect of maternal characteristics on placental development and perinatal outcomes. METHODS: This was a prospective cohort study including women seen between 11 and 14 weeks of pregnancy. Biophysical and biochemical markers included in the screening program for aneuploidy were recorded. Placental volume and vascularization indices were obtained using three-dimensional power-Doppler imaging and Virtual Organ Computer-aided Analysis (VOCAL) techniques. RESULTS: We compared 84 women with pre-eclampsia versus 904 non-affected. Placental volume and all vascular indices were lower in those with pre-eclampsia. Multivariate analysis showed that parity and maternal weight had a significant effect on placental volume and vascularization indices (p = 0.004 and p = 0.011). In women with pre-eclampsia, multiparity showed a negative effect on placental volume, gestational age, birth weight and Apgar test score. By contrast, in the non-affected group, multiparity had a protective effect. Low maternal weight had a significantly worse effect on placental vascularization and perinatal outcomes in women with pre-eclampsia. CONCLUSIONS: Women with pre-eclampsia showed significantly lower placental volume and vascularization indices at first trimester. Multiparity and low maternal weight independently exacerbated the negative effects of pre-eclampsia on placental characteristics and perinatal outcomes. © 2015 John Wiley & Sons, Ltd.


Asunto(s)
Placenta/patología , Preeclampsia/patología , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Imagenología Tridimensional , Tamaño de los Órganos , Placenta/irrigación sanguínea , Embarazo , Primer Trimestre del Embarazo , Estudios Prospectivos , Ultrasonografía Prenatal , Adulto Joven
16.
Fetal Diagn Ther ; 37(2): 117-22, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25170557

RESUMEN

OBJECTIVE: To determine whether the use of customized curves (CC) allows better detection of large- (LGA) or small-for-gestational age (SGA) infants at risk of adverse perinatal morbidity than non-CC in women with diabetes mellitus (DM). MATERIAL AND METHODS: A model of CC was applied to all infants of diabetic mothers (IDM) who attended the Hospital Universitario Materno Infantil de Canarias between 2008 and 2011. We compared perinatal outcomes of IDM classified as LGA or SGA by non-CC versus CC. RESULTS: One of 4 LGA was appropriate for gestational age (AGA) by CC (false-positive rate: 25%) and 30% of SGA by CC were not identified by non-CC (false-negative rate). False-positive LGA and SGA showed similar perinatal outcomes to AGA infants. The rates of cesarean section, cephalopelvic disproportion, total fetal distress and shoulder dystocia were significantly higher in false-negative LGA than in AGA by CC (p < 0.004, p < 0.02, p < 0.04 and p < 0.04, respectively). Fetal distress was higher in false-negative SGA than in AGA by CC (p < 0.03). DISCUSSION: In pregnancies complicated by DM, the use of CC allowed more accurate identification of LGA and SGA infants at high risk of perinatal morbidity than non-CC.


Asunto(s)
Peso al Nacer , Atención Perinatal/tendencias , Resultado del Embarazo/epidemiología , Embarazo en Diabéticas/diagnóstico , Embarazo en Diabéticas/epidemiología , Adulto , Peso al Nacer/fisiología , Femenino , Humanos , Recién Nacido , Masculino , Atención Perinatal/métodos , Embarazo , Estudios Retrospectivos
17.
Nanomaterials (Basel) ; 14(2)2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38251167

RESUMEN

Silicon is a promising alternative to graphite as an anode material in lithium-ion batteries, thanks to its high theoretical lithium storage capacity. Despite these high expectations, silicon anodes still face significant challenges, such as premature battery failure caused by huge volume changes during charge-discharge processes. To solve this drawback, using amorphous silicon as a thin film offers several advantages: its amorphous nature allows for better stress mitigation and it can be directly grown on current collectors for material savings and improved Li-ion diffusion. Furthermore, its conductivity is easily increased through doping during its growth. In this work, we focused on a comprehensive study of the influence of both electrical and structural properties of intrinsic and doped hydrogenated amorphous silicon (aSi:H) thin-film anodes on the specific capacity and stability of lithium-ion batteries. This study allows us to establish that hydrogen distribution in the aSi:H material plays a pivotal role in enhancing battery capacity and longevity, possibly masking the significance of the conductivity in the case of doped electrodes. Our findings show that we were able to achieve high initial specific capacities (3070 mAhg-1 at the 10th cycle), which can be retained at values higher than those of graphite for a significant number of cycles (>120 cycles), depending on the structural properties of the aSi:H films. To our knowledge, this is the first comprehensive study of the influence of these properties of thin films with different doping levels and hydrogen distributions on their optimization and use as anodes in lithium-ion batteries.

18.
Am J Biol Anthropol ; 183(1): 157-164, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37724468

RESUMEN

OBJECTIVES: Studying rib torsion is crucial for understanding the evolution of the hominid ribcage. Interestingly, there are variables of the rib cross section that could be associated with rib torsion and, consequently, with the morphology of the thorax. The aim of this research is to conduct a comparative study of the shape and mineralized tissues of the rib cross section in different hominids to test for significant differences and, if possible, associate them to different thoracic morphotypes. MATERIALS AND METHODS: The sample consists of the rib cross sections at the midshaft taken from 10 Homo sapiens and 10 Pan troglodytes adult individuals, as well as from A. africanus Sts 14. The shape of these rib cross sections was quantified using geometric morphometrics, while the mineralized tissues were evaluated using the compartmentalization index. Subsequently, covariation between both parameters was tested by a Spearman's ρ test, a permutation test and a linear regression. RESULTS: Generally, P. troglodytes individuals exhibit rib cross sections that are rounder and more mineralized compared to those of H. sapiens. However, the covariation between both parameters was only observed in typical ribs (levels 3-10). Although covariation was not found in the rib cross sections of Sts 14, their parameters are closer to P. troglodytes. DISCUSSION: On the one hand, the differences observed in the rib cross sections between H. sapiens and P. troglodytes might be related to different degrees of rib torsion and, consequently, to different thoracic 3D configurations. These findings can be functionally explained by considering their distinct modes of breathing and locomotion. On the other hand, although the rib cross sections belonging to Sts 14 are more similar to those of P. troglodytes, previous publications determined that their overall morphology is closer to modern humans. This discrepancy could reflect a diversity of post-cranial adaptations in Australopithecus.


Asunto(s)
Hominidae , Pan troglodytes , Adulto , Animales , Humanos , Pan troglodytes/anatomía & histología , Hominidae/anatomía & histología , Tórax/anatomía & histología , Costillas/anatomía & histología , Cráneo
19.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 1): 1-9, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38312155

RESUMEN

Two new copper dimers, namely, bis-(dimethyl sulfoxide)-tetra-kis-(µ-pyrene-1-carboxyl-ato)dicopper(Cu-Cu), [Cu2(C17H9O2)4(C2H6OS)2] or [Cu2(pyr-COO-)4(DMSO)2] (1), and bis-(di-methyl-formamide)-tetra-kis-(µ-pyrene-1-carboxyl-ato)dicopper(Cu-Cu), [Cu2(C17H9O2)4(C3H7NO)2] or [Cu2(pyr-COO-)4(DMF)2] (2) (pyr = pyrene), were synthesized from the reaction of pyrene-1-carb-oxy-lic acid, copper(II) nitrate and tri-ethyl-amine from solvents DMSO and DMF, respectively. While 1 crystallized in the space group P , the crystal structure of 2 is in space group P21/n. The Cu atoms have octa-hedral geometries, with four oxygen atoms from carboxyl-ate pyrene ligands occupying the equatorial positions, a solvent mol-ecule coordinating at one of the axial positions, and a Cu⋯Cu contact in the opposite position. The packing in the crystal structures exhibits π-π stacking inter-actions and short contacts through the solvent mol-ecules. The Hirshfeld surfaces and two-dimensional fingerprint plots were generated for both compounds to better understand the inter-molecular inter-actions and the contribution of heteroatoms from the solvent ligands to the crystal packing. In addition, a Cu2+/Cu1+ quasi-reversible redox process was identified for compound 2 using cyclic voltammetry that accounts for a diffusion-controlled electron-donation process to the Cu dimer.

20.
J Pharmacol Exp Ther ; 347(1): 100-16, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23892571

RESUMEN

Bombesin-receptor-subtype-3 (BRS-3) is an orphan G-protein-coupled receptor of the bombesin (Bn) family whose natural ligand is unknown and which does not bind any natural Bn-peptide with high affinity. It is present in the central nervous system, peripheral tissues, and tumors; however, its role in normal physiology/pathophysiology is largely unknown because of the lack of selective ligands. Recently, MK-5046 [(2S)-1,1,1-trifluoro-2-[4-(1H-pyrazol-1-yl)phenyl]-3-(4-{[1-(trifluoromethyl)cyclopropyl]methyl}-1H-imidazol-2-yl)propan-2-ol] and Bantag-1 [Boc-Phe-His-4-amino-5-cyclohexyl-2,4,5-trideoxypentonyl-Leu-(3-dimethylamino) benzylamide N-methylammonium trifluoroacetate], a nonpeptide agonist and a peptide antagonist, respectively, for BRS-3 have been described, but there have been limited studies on their pharmacology. We studied MK-5046 and Bantag-1 interactions with human Bn-receptors-human bombesin receptor subtype-3 (hBRS-3), gastrin-releasing peptide receptor (GRP-R), and neuromedin B receptor (NMB-R)-and compared them with the nonselective, peptide-agonist [d-Tyr6,ßAla11,Phe13,Nle14]Bn-(6-14) (peptide #1). Receptor activation was detected by activation of phospholipase C (PLC), mitogen-activated protein kinase (MAPK), focal adhesion kinase (FAK), paxillin, and Akt. In hBRS-3 cells, the relative affinities were Bantag-1 (1.3 nM) > peptide #1 (2 nM) > MK-5046 (37-160 nM) > GRP, NMB (>10 µM), and the binding-dose-inhibition curves were broad (>4 logs), with Hill coefficients differing significantly from unity. Curve-fitting demonstrated high-affinity (MK-5046, Ki = 0.08 nM) and low-affinity (MK-5046, Ki = 11-29 nM) binding sites. For PLC activation in hBRS-3 cells, the relative potencies were MK-5046 (0.02 nM) > peptide #1 (6 nM) > GRP, NMB, Bantag-1 (>10 µM), and MK-5046 had a biphasic dose response, whereas peptide #1 was monophasic. Bantag-1 was a specific hBRS-3-antagonist. In hBRS-3 cells, MK-5046 was a full agonist for activation of MAPK, FAK, Akt, and paxillin; however, it was a partial agonist for phospholipase A2 (PLA2) activation. The kinetics of activation/duration of action for PLC/MAPK activation of MK-5046 and peptide #1 differed, with peptide #1 causing more rapid stimulation; however, MK-5046 had more prolonged activity. Our study finds that MK-5046 and Bantag-1 have high affinity/selectivity for hBRS-3. The nonpeptide MK-5046 and peptide #1 agonists differ markedly in their receptor coupling, ability to activate different signaling cascades, and kinetics/duration of action. These results show that their hBRS-3 receptor activation is not always concordant and could lead to markedly different cellular responses.


Asunto(s)
Imidazoles/farmacología , Pirazoles/farmacología , Receptores de Bombesina/agonistas , Receptores de Bombesina/antagonistas & inhibidores , Células 3T3 , Animales , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Humanos , Imidazoles/metabolismo , Ratones , Ratones Endogámicos BALB C , Oligopéptidos/química , Oligopéptidos/metabolismo , Oligopéptidos/farmacología , Pirazoles/metabolismo , Receptores de Bombesina/metabolismo
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