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1.
Micromachines (Basel) ; 15(9)2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39337783

RESUMEN

Plasma focus devices represent a class of hot and dense plasma sources that serve a dual role in fundamental plasma research and practical applications. These devices allow the observation of various phenomena, including the z-pinch effect, nuclear fusion reactions, plasma filaments, bursts, shocks, jets, X-rays, neutron pulses, ions, and electron beams. In recent years, considerable efforts have been directed toward miniaturizing plasma focus devices, driven by the pursuit of both basic studies and technological advancements. In this paper, we present the design and construction of a compact, portable pulsed plasma source based on plasma focus technology, operating at the ~2-4 Joule energy range for versatile applications (PF-2J: 120 nF capacitance, 6-9 kV charging voltage, 40 nH inductance, 2.16-4.86 J stored energy, and 10-15 kA maximum current at short circuit). The components of the device, including capacitors, spark gaps, discharge chambers, and power supplies, are transportable within hand luggage. The electrical characteristics of the discharge were thoroughly characterized using voltage and current derivative monitoring techniques. A peak current of 15 kiloamperes was achieved within 110 nanoseconds in a short-circuit configuration at a 9 kV charging voltage. Plasma dynamics were captured through optical refractive diagnostics employing a pulsed Nd-YAG laser with a 170-picosecond pulse duration. Clear evidence of the z-pinch effect was observed during discharges in a deuterium atmosphere at 4 millibars and 6 kilovolts. The measured pinch length and radius were approximately 0.8 mm and less than 100 µm, respectively. Additionally, we explore the potential applications of this compact pulsed plasma source. These include its use as a plasma shock irradiation device for analyzing materials intended for the first wall of nuclear fusion reactors, its capability in material film deposition, and its utility as an educational tool in experimental plasma physics. We also show its potential as a pulsed plasma thruster for nanosatellites, showcasing the advantages of miniaturized plasma focus technology.

2.
Sensors (Basel) ; 24(8)2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38676159

RESUMEN

The presence of green areas in urbanized cities is crucial to reduce the negative impacts of urbanization. However, these areas can influence the signal quality of IoT devices that use wireless communication, such as LoRa technology. Vegetation attenuates electromagnetic waves, interfering with the data transmission between IoT devices, resulting in the need for signal propagation modeling, which considers the effect of vegetation on its propagation. In this context, this research was conducted at the Federal University of Pará, using measurements in a wooded environment composed of the Pau-Mulato species, typical of the Amazon. Two machine learning-based propagation models, GRNN and MLPNN, were developed to consider the effect of Amazonian trees on propagation, analyzing different factors, such as the transmitter's height relative to the trunk, the beginning of foliage, and the middle of the tree canopy, as well as the LoRa spreading factor (SF) 12, and the co-polarization of the transmitter and receiver antennas. The proposed models demonstrated higher accuracy, achieving values of root mean square error (RMSE) of 3.86 dB and standard deviation (SD) of 3.8614 dB, respectively, compared to existing empirical models like CI, FI, Early ITU-R, COST235, Weissberger, and FITU-R. The significance of this study lies in its potential to boost wireless communications in wooded environments. Furthermore, this research contributes to enhancing more efficient and robust LoRa networks for applications in agriculture, environmental monitoring, and smart urban infrastructure.

3.
Sensors (Basel) ; 24(5)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38475155

RESUMEN

Designing and deploying telecommunications and broadcasting networks in the challenging terrain of the Amazon region pose significant obstacles due to its unique morphological characteristics. Within low-power wide-area networks (LPWANs), this research study introduces a comprehensive approach to modeling large-scale propagation loss channels specific to the LoRaWAN protocol operating at 915 MHz. The objective of this study is to facilitate the planning of Internet of Things (IoT) networks in riverside communities while accounting for the mobility of end nodes. We conducted extensive measurement campaigns along the banks of Universidade Federal do Pará, capturing received signal strength indication (RSSI), signal-to-noise ratio (SNR), and geolocated point data across various spreading factors. We fitted the empirical close-in (CI) and floating intercept (FI) propagation models for uplink path loss prediction and compared them with the Okumura-Hata model. We also present a new model for path loss with dense vegetation. Furthermore, we calculated received packet rate statistics between communication links to assess channel quality for the LoRa physical layer (PHY). Remarkably, both CI and FI models exhibited similar behaviors, with the newly proposed model demonstrating enhanced accuracy in estimating radio loss within densely vegetated scenarios, boasting lower root mean square error (RMSE) values than the Okumura-Hata model, particularly for spreading factor 9 (SF9). The radius coverage threshold, accounting for node mobility, was 945 m. This comprehensive analysis contributes valuable insights for the effective deployment and optimization of LoRa-based IoT networks in the intricate environmental conditions of the Amazon region.

4.
J Acad Nutr Diet ; 124(4): 521-530.e4, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-37541326

RESUMEN

BACKGROUND: Public policies to contain the spread of coronavirus disease in Mexico could have had an effect on food purchase patterns. OBJECTIVE: The objective of the study was to assess changes in the quantity of food and beverages purchased and proportion spent on food consumed away from home during the coronavirus disease pandemic in Mexican households. DESIGN: This study is a secondary analysis of cross-sectional data from the National Household Income and Expenditure Survey 2014-2020. PARTICIPANTS/SETTING: The study included 234,631 households with information on food and beverages purchases from 2014 to 2020. MAIN OUTCOME MEASURES: Food and beverage purchases were classified into six categories: basic, nonbasic energy-dense foods, prepared food for consumption at home, water, milk, and sugar-sweetened beverages. In the National Household Income and Expenditure Survey 2014-2020, expenditures on food and beverages consumed away from home are not classified into any specific items but represents more than 10% of food and beverage expenditures; therefore, the analyses included the proportion of food and beverage expenditures spent on food consumed away from home. STATISTICAL ANALYSES PERFORMED: A two-part model was used to evaluate changes in the quantity of food purchased and the proportion spent away from home during the coronavirus disease pandemic in 2020 compared with 2018, adjusting for socio-demographic variables, gross domestic product and previous survey rounds. Results are presented at the national level, by income quintile and by place of residence. RESULTS: Purchases of basic food increased by 17 g/capita/day at the national level and 22.4 g/capita/day in urban areas (P < 0.001). Purchases of nonbasic energy-dense foods decreased both at the national level (-4.2 g/capita/day; P < 0.001) and by place of residence (-4.8 g/capita/day; P < 0.001 in urban areas and -2.5 g/capita/day; P = 0.001 in rural settings). Purchases of prepared food increased 16 g/capita/day (P < 0.001). In rural areas, purchases of sugar-sweetened beverages increased 7.2 mL/per capita/day (P < 0.001). For the lowest income quintile purchases of processed meat increased 2.4 g/capita/day (P < 0.001). The proportion spent on food consumed away from home decreased by -44.9% (P < 0.001). CONCLUSIONS: Results of this study show that during the coronavirus disease lockdown there was an increase in basic and prepared food purchases, whereas purchases of nonbasic energy-dense foods and the proportion spent on food consumed away from home decreased. However, findings showed an increase in sugar-sweetened beverages purchases among rural dwellers and an increase in purchases of processed meat among the lowest income quintile. Various factors such as income reductions, unemployment, mobility restrictions, or increases in prices may have led the observed changes. Future research should be conducted to analyze these potential pathways.


Asunto(s)
Infecciones por Coronavirus , Coronavirus , Humanos , Animales , México/epidemiología , Estudios Transversales , Pandemias , Bebidas , Comportamiento del Consumidor , Leche , Comercio
5.
Drug Deliv Transl Res ; 14(1): 62-79, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37566362

RESUMEN

The aim of this work was to develop a dense lamellar scaffold, as a biomimetic material with potential applications in the regeneration of tracheal tissue after surgical tumor resection. The scaffolds were produced by plastic compression technique, exploiting the use of total phenolic compounds (TPC) from Psidium guajava Linn as a potential cross-linking agent in a polymeric mixture based on collagen (COL), silk fibroin (SF), and polyethylene glycol 400 (PEG 400). Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) confirmed the chemical interactions between the polymers and the cross-linking of TPC between COL and SF. Morphological analyses showed scaffolds with porosity, interconnectivity, and a porous surface structure with a gyroid-like geometry. The analysis of the anisotropic degree resulted in anisotropic structures (0.1% TFC and 0.3% TFC) and an isotropic structure (0.5% TFC). In the mechanical properties, it was evidenced greater resistance for the 0.3% TFC formulation. The addition of TPC percentages did not result in a significant difference (p > 0.05) in swelling capacity and disintegration rate. The results confirmed that TPC were able to modulate the morphological, morphometric, and mechanical properties of scaffolds. Thus, this study describes a potential new material to improve the regeneration of major tracheal structures after surgical tumor removal.


Asunto(s)
Fibroínas , Neoplasias , Psidium , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Fibroínas/química , Colágeno/química , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier
6.
Clin Ophthalmol ; 17: 2405-2412, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37605764

RESUMEN

Purpose: To determine the energy expenditure in phacoemulsification surgery expressed as cumulative dissipated energy (CDE) among the divide and conquer, ultrachopper-assisted divide and conquer, and phaco-chop techniques for dense cataract removal. Patients and Methods: The clinical data were obtained from the medical charts of dense cataracts patients undergoing routine phacoemulsification employing any of three phaco-fragmentation techniques, including divide and conquer using the Kelman 0.9 mm tip, the ultrachopper tip, and the phaco-chop technique using the Kelman 0.9 mm tip. Cumulated dissipated energy (CDE), longitudinal ultrasound time (UST), and endothelial cell loss were compared among groups at the one-month postoperative. Results: Surgeries from 90 eyes were analyzed, among whom the conventional divide-and-conquer technique group included 30 patients, 32 in the ultrachopper group, and 28 in the phaco-chop technique group. The average CDE in the conventional divide and conquer group was 44.52 ± 23.00, the ultrachopper technique was 43.27 ± 23.18, and 20.11 ± 11.06 in the phaco-chop group. Phaco-fragmentation chop demonstrated significantly lower CDE than the other techniques (p= <0.0001). The phaco-chop technique showed statistically significantly lower CDE when compared to the other two groups (p=<0.0001) with 93.96 ± 39.71 seconds. There were no statistically significant differences in postoperative endothelial cell density between groups (p=0.4916). Conclusion: The use of the phaco-chop technique in hard cataract phacoemulsification represents a lower energy expenditure than divide and conquer and ultrachopper techniques; nevertheless, no differences regarding endothelial density loss were evidenced.

7.
Food Chem Toxicol ; 176: 113750, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37023972

RESUMEN

An unhealthy lifestyle is associated with metabolic disorders and neuroinflammation. In this study, the efficacy of m-trifluoromethyl-diphenyl diselenide [(m-CF3-PhSe)2] against lifestyle model-related metabolic disturbances and hypothalamic inflammation in young mice was investigated. From postnatal day 25 (PND25) to 66, male Swiss mice were subjected to a lifestyle model, an energy-dense diet (20:20% lard: corn syrup) and sporadic ethanol (3x/week). Ethanol was administrated intragastrically (i.g., 2 g/kg) to mice from PND45 to 60. From PND60 to 66, mice received (m-CF3-PhSe)2 (5 mg/kg/day; i. g). (m-CF3-PhSe)2 reduced relative abdominal adipose tissue weight, hyperglycemia, and dyslipidemia in mice exposed to the lifestyle-induced model. (m-CF3-PhSe)2 normalized hepatic cholesterol and triglyceride levels, and the activity of G-6-Pase increased in lifestyle-exposed mice. (m-CF3-PhSe)2 was effective in modulating hepatic glycogen levels, citrate synthase and hexokinase activities, protein levels of GLUT-2, p-IRS/IRS, p-AKT/AKT, redox homeostasis, and inflammatory profile of mice exposed to a lifestyle model. (m-CF3-PhSe)2 counteracted hypothalamic inflammation and the ghrelin receptor levels in mice exposed to the lifestyle model. (m-CF3-PhSe)2 reversed the decreased levels of GLUT-3, p-IRS/IRS, and the leptin receptor in the hypothalamus of lifestyle-exposed mice. In conclusion, (m-CF3-PhSe)2 counteracted metabolic disturbances and hypothalamic inflammation in young mice exposed to a lifestyle model.


Asunto(s)
Proteínas Proto-Oncogénicas c-akt , Roedores , Animales , Masculino , Ratones , Hipotálamo , Inflamación/tratamiento farmacológico
8.
Methods Mol Biol ; 2565: 283-296, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36205901

RESUMEN

Chromaffin granules isolated from adrenal glands constitute a powerful experimental tool to the study of secretory vesicle components and their participation in fusion and docking processes, vesicle aggregation, and interactions with cytosolic components. Although it is possible to isolate and purify chromaffin granules from adrenal glands of different species, bovine adrenal glands are the most used tissue source due to its easy handling and the large amount of granules that can be obtained from this tissue. In this chapter, we describe an easy-to-use and short-term protocol for efficiently obtaining highly purified chromaffin granules from bovine adrenal medulla. We additionally include protocols to isolate granules from cultured bovine chromaffin cells and PC12 cells, as well as a section to obtain chromaffin granules from mouse adrenal glands.


Asunto(s)
Médula Suprarrenal , Células Cromafines , Células Neuroendocrinas , Glándulas Suprarrenales , Animales , Bovinos , Gránulos Cromafines , Ratones , Células PC12 , Ratas
9.
Sensors (Basel) ; 22(21)2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36365860

RESUMEN

We demonstrate, numerically, a new concept for on-chip magneto-optical (MO) modulation in dense wavelength division multiplexing (DWDM) applications. Our idea uses materials and mechanisms that are compatible with current silicon-on-insulator fabrication and CMOS technologies for monolithic integration. The physics behind our idea stems in the exploitation of the enhanced MO activity of a micro-ring, made of cerium substituted yttrium iron garnet (Ce:YIG) material, to actively manipulate the resonance wavelengths of an adjacent micro-ring resonator (MRR) of silicon (Si). This active manipulation of the latter MO-MRR structure is used to modulate the optical signal traveling through a side-coupled Si bus waveguide. Moreover, by proper tailoring multiple MO-MRRs (side-coupled to the single Si bus waveguide) to match wavelength channels in DWDM across the entire C-band optical communications spectrum, we extend our proposal to massive and dynamic MO modulation in DWDM applications. Significantly, we noticed that the active MO shifting of the resonant wavelength (used for MO modulation here) can be used for improvements in the spectrum utilization efficiency in future elastic optical networks (EONs).

10.
Front Endocrinol (Lausanne) ; 13: 916042, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35813659

RESUMEN

Gestational diabetes mellitus (GDM), is one of the most important pregnancy complications affecting approximately 15% of pregnant women. It is related to several gestational adverse outcomes in the fetus, e.g., macrosomia, shoulder dystocia, stillbirth, neonatal hypoglycemia, and respiratory distress. Women with GDM have a high risk of developing type 2 diabetes in the future. The pathogenesis of GDM is not completely understood; nevertheless, two factors could contribute to its development: ß-cell dysfunction and failure in insulin secretion in response to insulin resistance induced by gestation. Both processes, together with the physiological activities of the insulin-like growth factors (IGFs), play a crucial role in glucose transport to the fetus and hence, fetal growth and development. IGFs (both IGF-1 and IGF-2) and their binding proteins (IGFBPs) regulate glucose metabolism and insulin sensitivity. Maternal nutritional status determines the health of the newborn, as it has substantial effects on fetal growth and development. Maternal obesity and an energy-dense diet can cause an increase in insulin and IGF-1 serum levels, producing metabolic disorders, such as insulin resistance, GDM, and high birth weight (> 4,000 g) due to a higher level of body fat. In this way, in GDM pregnancies there is an increase in IGF-1 and IGF-2 serum levels, and a decrease in IGFBP-1 and 4 serum levels, suggesting the crucial role of the insulin/IGF system in this gestational outcome. Here, the present review tries to elucidate the role that energy-dense diets and the insulin/IGF-1 signaling pathway perform in GDM pregnancies.


Asunto(s)
Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Resistencia a la Insulina , Dieta , Femenino , Humanos , Recién Nacido , Insulina , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor II del Crecimiento Similar a la Insulina , Embarazo
11.
Front Psychol ; 13: 803326, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35874367

RESUMEN

Diets based on meals that provide a large amount of energy and consumed frequently often increase the rate of growth of the body mass index (overweight or obesity) and, in turn, the risk of suffering from non-communicable diseases. In order to make a food choice, it is necessary to search for foods in the environment, taking into account physical and social variables (contextual variables) which, together with individual variables, delimit the situation of food selection. The objective of this study was to evaluate the effect of social facilitation, portion size, salience of food, and food preference or rejection on the selection of energy-dense foods by young college students. To do so, we performed a factorial experiment in which unaccompanied and accompanied participants (levels of social facilitation) as they went through the process of choosing from different options of main dishes, beverages, and desserts then noted the reasons for their selection (preference or rejection of the food). Results showed significant differences between the group of accompanied participants and salience of food in the selection of the energy-dense main dishes and desserts (pizza, spaghetti, and chocolate cake). A significant relationship was also identified between accompanied participants, hedonistic/sensory reasons (food preference or rejection category), and salience of food in the selection of the energy-dense main dishes. In conclusion, key findings of the variables that constitute the situation that predicts the selection of energy-dense foods have emerged from this study, when participants and the given level of social facilitation (in this case, being accompanied) were faced with the conditions of the food salience of the meals of their preference regarding its taste and appearance.

12.
Indian J Ophthalmol ; 70(1): 107-111, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34937218

RESUMEN

PURPOSE: To assess the axial length (AL) measurement failure rate using partial-coherence interferometry (PCI) and swept-source optical coherence tomography (SS-OCT) in dense cataracts. As a secondary outcome, the SS-OCT biometry was compared to immersion ultrasound. METHODS: This is a prospective cross-sectional and comparative study. Seventy eyes from 70 patients with dense cataracts were enrolled in this study. Dense cataract was defined according to the Lens Opacities Classification System III (LOCS III) scores equal to or more than NO4, NC4, C4, and P3. The failure rate of AL measurement was evaluated using PCI and SS-OCT. Anterior chamber depth (ACD), lens thickness (LT), and AL measurements obtained by SS-OCT were compared with IUS. RESULTS: AL measurement failure rate with PCI was 68.57% and 21.43% with SS-OCT (P = 0.007). AL measurement was achieved in 69.23% of NO4, 66.6% of P3, and 15.3% of mixed cataracts using PCI, while SS-OCT was achieved in 100% of NO4, NO5, P3, and P5 and 76.9% of mixed cataracts. Cortical cataracts alone did not influence AL measurement. Biometric data of ACD, LT, and AL were statistically different comparing US and SS-OCT with a good correlation of AL. CONCLUSION: SS-OCT significantly improves the rate of successful AL measurements when compared to PCI in dense cataracts. The LOCS III clinical cut-off for the use of SS-OCT ocular biometry may well be up to P4 and NO5.


Asunto(s)
Catarata , Tomografía de Coherencia Óptica , Cámara Anterior , Longitud Axial del Ojo/diagnóstico por imagen , Biometría , Catarata/diagnóstico , Estudios Transversales , Humanos , Inmersión , Interferometría , Estudios Prospectivos , Reproducibilidad de los Resultados
13.
Acupunct Med ; 40(2): 169-177, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34758667

RESUMEN

BACKGROUND: Neuropathic pain (NP) is a complex disease that remains challenging to treat. Low-frequency dense-and-disperse (DD) electroacupuncture (EA) has been used as adjuvant therapy for neuropathic pain; however, its analgesic effect decreases as stimulation time increases, or when it is repeatedly used. We hypothesized that a new frequency parameter could improve the effectiveness of EA, and aimed to compare the efficacy and duration of the analgesic effect between classic DD-EA and non-repetitive and non-sequential frequency (random frequency (RF)-EA) in neuropathic rats. Furthermore, the effect of RF-EA at local traditional acupuncture point locations versus auricular vagus nerve stimulation (aVNS) was evaluated. METHODS: Male Wistar rats with peripheral neuropathy were subjected to a single session of DD-EA or RF-EA for 20 or 40 min at ST36 + GB34. An additional group of rats was treated with RF-EA for 20 min using aVNS at the appropriate ear point locations. Paw pressure test, von Frey filaments and spontaneous pain scores were evaluated. Sham-operated rats were used as controls. RESULTS: In all, 20 min of RF-EA reversed hyperalgesia (for 24 h) and allodynia (for 8 h), showing a longer analgesic effect than DD-EA. Both RF-EA and DD-EA induced partial inhibition of spontaneous pain for 8 h. Forty minutes of DD-EA did not interfere with the NP phenomena; however, RF-EA induced significant long-term analgesia. aVNS induced an analgesic effect similar to local stimulation. CONCLUSION: This pilot study shows that RF-EA at both local traditional acupuncture point and auriculotherapy point locations induces long-lasting analgesia in neuropathic rats, and more effectively so than classical DD-EA.


Asunto(s)
Electroacupuntura , Neuralgia , Animales , Masculino , Neuralgia/terapia , Proyectos Piloto , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Roedores
14.
Pap. avulsos zool ; 62: e202262026, 2022. tab, graf
Artículo en Inglés | VETINDEX | ID: biblio-1386613

RESUMEN

Mixed flocks are associations of two or more species that are formed and maintained through mutual behavioral responses, with advantages such as maximizing foraging and protecting against predation. This study aimed to evaluate the composition, temporal dynamics, and presence of core species in mixed flocks of birds in a remnant of the Submontane Atlantic Rain Forest in the Parque Nacional Aparados da Serra, southern Santa Catarina state, Brazil. Data collection took place from October 2016 to September 2017 through monthly campaigns, consisting of three consecutive observation days, with sampling sessions of six hours per day, resulting in a total effort of 216 h of observations. For each contact with the flocks, we recorded the species and number of individuals, stratum of occurrence, substrates of search, and agonistic interactions. We recorded 152 mixed flocks, with a total of 76 species belonging to 24 families, and five orders, with Thraupidae, Tyrannidae, Furnariidae, and Rhynchocyclidae being the richest. The flocks had an average of 4.5 ± 2.7 species and 8.7 ± 5.8 individuals, with richness and the number of individuals being positively correlated (R² = 0.8). Mixed flocks occurred throughout the year. There was a great variation in the number of contacts from October to February (from 5 to 20 contacts). Meanwhile from March to September, the coldest period of the year in the region, the number of contacts did not vary (from 9 to 14 contacts). However, there was no difference in the number of contacts between these months (z = 0.37; p = 0.691). Basileuterus culicivorus and Habia rubica were the core species because, in addition to their high participation (46.7 and 32.9%, respectively), they showed frequent and conspicuous movement and vocalization. Thus, a high capacity to enlist a greater number of individuals from different species for the flocks was demonstrated.(AU)


Asunto(s)
Animales , Passeriformes/fisiología , Distribución Temporal , Distribución Animal , Brasil , Biota
15.
Metabolites ; 11(12)2021 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-34940565

RESUMEN

Type 2 diabetes mellitus and insulin resistance feature substantial modifications of the lipoprotein profile, including a higher proportion of smaller and denser low-density lipoprotein (LDL) particles. In addition, qualitative changes occur in the composition and structure of LDL, including changes in electrophoretic mobility, enrichment of LDL with triglycerides and ceramides, prolonged retention of modified LDL in plasma, increased uptake by macrophages, and the formation of foam cells. These modifications affect LDL functions and favor an increased risk of cardiovascular disease in diabetic individuals. In this review, we discuss the main findings regarding the structural and functional changes in LDL particles in diabetes pathophysiology and therapeutic strategies targeting LDL in patients with diabetes.

16.
Rev. colomb. cienc. pecu ; 34(3): 189-199, July-Sept. 2021. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1408020

RESUMEN

Abstract Background: The use of early nutrient-restriction programs in broilers can prevent complications such as increased body fat deposition and its consequences. However, feed restriction not always gives the expected results. Objective: To assess the effect of two levels of feed restriction followed by a re-alimentation period with five increasing nutrient levels on growth performance and immune response of broiler chickens. Methods: A total of 330 animals were used. The treatments were: 25 (T25) and 35% (T35) quantitative feed restriction during the starting period, and 0, 2.5, 5, 7.5, 10, and 15% increased energy and protein contents during the growing and finishing periods. Results: For all the T25 treatments, except for T25-0, feed intake (FI) and body weight gain (BWG) were higher, and feed conversion rate (FCR) was lower (p<0.05) compared to the control treatment. In that group, the response of FI and BWG to the increased nutrient density was mostly quadratic (p<0.001), whereas that of FCR was linear (p<0.001). The FI and BWG results were less homogeneous in the T35 treatments, but FCR was lower compared to the control treatment (p<0.05) in all of them. The FCR showed no differences (p>0.05) between treatments during the finishing period. Conclusion: Feeding a nutrient-dense diet after a period of mild feed restriction gives the best results, while increasing nutrient density after a more severe feed restriction does not improve productive results compared to a standard diet. Carcass traits and immune function were not affected by restriction level or nutrient density.


Resumen Antecedentes: El uso de programas de restricción alimenticia temprana en pollos de engorde puede prevenir el incremento de la deposición de grasa corporal y sus consecuencias. Sin embargo, la restricción alimenticia no proporciona siempre los resultados esperados. Objetivo: Investigar los efectos de dos niveles de restricción alimenticia seguida por un período de realimentación con cinco niveles crecientes de nutrientes sobre el rendimiento productivo y la respuesta inmune de pollos de engorde. Métodos: Se utilizaron 330 animales. Los tratamientos fueron: restricción cuantitativa del 25 (T25) y del 35% (T35) durante el periodo de iniciación y aumento de la energía y contenido proteico de la dieta del 0, 2,5, 5, 7,5, 10 y 15% durante los periodos de crecimiento y finalización. Resultados: Para casi todos los T25 el consumo de alimento (FI) y el aumento de peso corporal (BWG) fueron mayores y el índice de conversión (FCR) menor (p<0,05) en comparación con el control. La respuesta del FI y el BWG al aumento de la densidad de nutrientes en este grupo fue mayoritariamente cuadrática (p<0,001), mientras que en el caso del FCR fue lineal (p<0,001). Los resultados del FI y el BWG fueron menos homogéneos en los T35, pero el FCR fue menor que en el control (p<0,05). El FCR no mostró diferencias (p>0,05) entre tratamientos durante el periodo de acabado. Conclusión: La alimentación con una dieta rica en nutrientes después una restricción ligera proporciona los mejores resultados, mientras que el incremento de la densidad de la dieta después de una restricción severa no mejora los resultados productivos en comparación con una dieta estándar. Las características de la canal y la respuesta inmune no se vieron afectadas por el nivel de restricción o la densidad de nutrientes de la dieta.


Resumo Antecedentes: O uso de programas de restrição precoce de nutrientes em frangos de corte tem o potencial de prevenir complicações como o aumento da deposição de gordura corporal e suas consequências. No entanto, a restrição alimentar nem sempre dá os resultados esperados. Objetivo: Investigar os efeitos de dois níveis de restrição alimentar seguidos de um período de re-alimentação com cinco níveis crescentes de nutrientes no rendimento produtivo e na resposta imune de frangos de corte. Métodos: Foram utilizados 330 animais. Os tratamentos foram: restrição quantitativa de 25 (T25) e 35% (T35) durante o período inicial e aumento do conteúdo energético e proteico da dieta de 0, 2,5, 5, 7,5, 10 e 15% durante os períodos de crescimento e finalização. Resultados: Para todos os tratamentos T25, menos para T25-0, consumo de ração (FI) e ganho de peso corporal (BWG) foram maiores e a taxa de conversão (FCR) foi menor (p<0,05) o controle. A resposta do FI e do BWG ao aumento da densidade de nutrientes nesse grupo foi principalmente quadrática (p<0,001), enquanto no caso da FCR foi linear (p<0,001). Os resultados do FI e do BWG foram menos homogêneos nos tratamentos T35, mas o FCR foi menor que no tratamento controle (p<0,05). O FCR não apresentou diferenças (p>0,05) entre os tratamentos durante o período de terminação. Nenhuma tendência clara foi observada no peso relativo dos órgãos linfóides ou na resposta imune devido aos tratamentos testados. Conclusão: A alimentação de uma dieta rica em nutrientes após um período de restrição leve proporcionou os melhores resultados, enquanto o aumento da densidade de nutrientes na dieta após uma restrição severa não melhorou os resultados produtivos em comparação com uma dieta padrão.

17.
MethodsX ; 8: 101374, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34430270

RESUMEN

Two types of secretory vesicles co-exist at some presynaptic terminals. Clear synaptic vesicles (CSV) release their contents at the synaptic active zone, upon single impulses, while dense-core vesicles (DCV) usually release their contents in the periphery of the terminal upon repetitive stimulation. Part of the transmitter released by DCV diffuses to produce paracrine effects, and part of it reaches the postsynaptic terminal, adding its effect to that of synaptic release. This article presents an analytical method to separate the contribution of CSV and DCV to the postsynaptic responses, based on the kinetics of postsynaptic currents (PSCs). Since stimulation with single presynaptic impulses usually triggers release only from CSV, the kinetics of the resulting PSC can be used as a template to model the postsynaptic response to release from CSV during stimulation trains, accounting for the variations in the amplitude of PSCs due to short-term synaptic plasticity. Subtraction of this model simulation to the total recorded PSC renders the response to DCV peri­synaptic release, which has slower kinetics. The method can be further simplified by measuring only the amplitudes of the PSC peaks for synaptic release and the integral of the current for peri­synaptic release.•The postsynaptic current in response to presynaptic release from clear synaptic vesicles is modeled using the kinetics of the PSC in response to single impulses.•The model synaptic response is subtracted from the total recorded PSC to obtain the response to peri­synaptic release from dense-core vesicles.

18.
BMC Cancer ; 21(1): 525, 2021 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-33964923

RESUMEN

BACKGROUND: Benefit of carboplatin and dose-dense weekly paclitaxel (ddCT) in first line treatment of ovarian cancer patients has been different in Western and Asian studies. In the present study we compare progression-free survival (PFS) of ddCT to three-weekly carboplatin and paclitaxel (CT) in first-line treatment of ovarian carcinoma in a single institution in a Western population. MATERIALS AND METHODS: We conducted a retrospective review of medical records from patients with ovarian carcinoma treated in a tertiary cancer center from 2007 to 2018. All patients treated with ddCT or CT in the first-line setting were included. Patients who received first-line bevacizumab were not included. PFS and overall survival (OS) were compared in a propensity score-matched cohort to address selection bias. Patients were matched according to age, ECOG performance status, CA 125, FIGO stage, residual disease, and histological subtype, in a 1:2 ratio. RESULTS: Five hundred eighty-eight patients were eligible for propensity score matching, the final cohort consisted of 69 patients treated with ddCT and 138 CT group. Baseline characteristics were well-balanced. After a median follow-up of 65.1 months, median PFS was 29.3 vs 20.0 months, favouring ddCT treatment (p = 0.035). In the multivariate cox regression ddCT showed a 18% lower risk of progression (HR 0.82, 95% CI 0.68-0.99, p = 0.04). Overall survival data is immature, but suggested better outcomes for ddCT (not reached versus 78.8 months; p = 0.07). CONCLUSION: Our retrospective study has shown superior PFS of ddCT over CT regimen in first-line treatment of ovarian carcinoma in a Western population not treated with bevacizumab.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carboplatino/administración & dosificación , Neoplasias Ováricas/tratamiento farmacológico , Paclitaxel/administración & dosificación , Puntaje de Propensión , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/mortalidad , Estudios Retrospectivos
19.
Caries Res ; 55(3): 183-192, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33853058

RESUMEN

In January 2014, taxes on sugar-sweetened beverages and nonessential energy-dense food were implemented in Mexico to discourage the consumption of these products. Published evaluations have shown reductions in purchases of taxed food and beverages associated with the implementation of this fiscal policy. Although there are some studies on the impact on health based on simulation studies, no evaluations with empirical data on changes in oral health have been published. We used administrative records and data from an epidemiological surveillance system to estimate changes in (1) outpatient visits related to dental caries; (2) having experienced dental caries: Decayed, Missing and Filled Teeth (DMFT) >0 for permanent dentition or dmft >0 for primary dentition (dmft); (3) number of teeth with caries experience (DMFT and dmft), (4) cases with DMFT >0 or dmft >0, and (5) the series of mean DMFT or dmft, associated with the taxes. We estimated probit and negative binomial models for outcomes at individual level, and interrupted time series analysis for population-level outcomes. The implementation of the taxes was associated with negative changes in the trends of outpatient visits, as well as for cases with DMFT >0, dmft >0 and mean DMFT. Taxes were also associated with a lower probability of having experienced dental caries and with a lower number of teeth with caries experience in the samples studied. Our results suggest positive impacts of the implementation of taxes on unhealthy food and beverages in the oral health of Mexicans, which are the first health benefits observed, and add to the health benefits predicted by modeling studies.


Asunto(s)
Caries Dental , Salud Bucal , Bebidas/efectos adversos , Índice CPO , Caries Dental/epidemiología , Caries Dental/etiología , Caries Dental/prevención & control , Humanos , México/epidemiología , Impuestos
20.
Front Plant Sci ; 12: 591587, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33664755

RESUMEN

Plant height (PH) is an essential trait in the screening of most crops. While in crops such as wheat, medium stature helps reduce lodging, tall plants are preferred to increase total above-ground biomass. PH is an easy trait to measure manually, although it can be labor-intense depending on the number of plots. There is an increasing demand for alternative approaches to estimate PH in a higher throughput mode. Crop surface models (CSMs) derived from dense point clouds generated via aerial imagery could be used to estimate PH. This study evaluates PH estimation at different phenological stages using plot-level information from aerial imaging-derived 3D CSM in wheat inbred lines during two consecutive years. Multi-temporal and high spatial resolution images were collected by fixed-wing (P l a t F W ) and multi-rotor (P l a t M R ) unmanned aerial vehicle (UAV) platforms over two wheat populations (50 and 150 lines). The PH was measured and compared at four growth stages (GS) using ground-truth measurements (PHground) and UAV-based estimates (PHaerial). The CSMs generated from the aerial imagery were validated using ground control points (GCPs) as fixed reference targets at different heights. The results show that PH estimations using P l a t F W were consistent with those obtained from P l a t M R , showing some slight differences due to image processing settings. The GCPs heights derived from CSM showed a high correlation and low error compared to their actual heights (R 2 ≥ 0.90, RMSE ≤ 4 cm). The coefficient of determination (R 2) between PHground and PHaerial at different GS ranged from 0.35 to 0.88, and the root mean square error (RMSE) from 0.39 to 4.02 cm for both platforms. In general, similar and higher heritability was obtained using PHaerial across different GS and years and ranged according to the variability, and environmental error of the PHground observed (0.06-0.97). Finally, we also observed high Spearman rank correlations (0.47-0.91) and R 2 (0.63-0.95) of PHaerial adjusted and predicted values against PHground values. This study provides an example of the use of UAV-based high-resolution RGB imagery to obtain time-series estimates of PH, scalable to tens-of-thousands of plots, and thus suitable to be applied in plant wheat breeding trials.

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