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1.
J Pers Med ; 14(4)2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38673006

RESUMEN

AIM: The temporal avascular area of the retina and the duration of mechanical ventilation (DMV) may predict the need to treat retinopathy of prematurity (ROP). This study considers whether the rate of retinal vascularisation and related risk factors should be included in a predictive model of the need for ROP treatment. METHODS: This single-centre, observational retrospective case-control study was conducted on 276 preterm infants included in an ROP screening programme. All had undergone at least three examinations of the fundus. The main outcome measures considered were DMV (in days of treatment), the temporal avascular area (in disc diameters, DD) and the rate of temporal retinal vascularisation (DD/week). RESULTS: The multivariate logistic model that best explains ROP treatment (R2 = 63.1%) has three significant risk factors: each additional day of mechanical ventilation (OR, 1.05 [95% CI, 1.02-1.09]; p = 0.001); each additional DD of temporal avascular area (OR, 2.2 [95% CI, 1.7-2.9]; p < 0.001) and a vascularisation rate <0.5 DD/week (OR, 19.0 [95% CI, 6.5-55.5]; p < 0.001). Two tables are presented for calculating the expected need for ROP treatment according to these three risk factors. CONCLUSIONS: A greater DMV, a broad avascular area of the temporal retina at the first binocular screening and slow retinal vascularisation strongly predict the need for ROP treatment. The predictive model we describe must be validated externally in other centres.

2.
Nanoscale ; 16(14): 7093-7101, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38497989

RESUMEN

Pyrazole derivatives are key in crystal engineering and liquid crystal fields and thrive in agriculture, pharmaceutical, or biomedicine industries. Such versatility relies in their supramolecular bond adaptability when forming hydrogen bonds or metal-pyrazole complexes. Interestingly, the precise structure of pyrazole-based macrocycles forming widespread porous structures is still unsolved. We bring insight into such fundamental question by studying the self-assembled structures of a bis-pyrazole derivative sublimed in ultra-high-vacuum conditions (without solvents) onto the three (111) noble metal surfaces. By means of high-resolution scanning tunneling microscopy that is validated by gas phase density functional theory calculations, we find a common hexagonal nanoporous network condensed by triple hydrogen bonds at the molecule-metal interface. Such assembly is disrupted and divergent after annealing: (i) on copper, the molecular integrity is compromised leading to structural chaos, (ii) on silver, an incommensurate new oblique structure requiring molecular deprotonation is found and, (iii) on gold, metal-organic complexes are promoted yielding irregular chain structures. Our findings confirm the critical role of these metals on the different pyrazole nanoporous structure formation, discarding their preference for metal incorporation into the connecting nodes whenever there is no solvent involved.

3.
Acta Ophthalmol ; 102(4): e628-e634, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38146930

RESUMEN

PURPOSE: Twin-twin transfusion syndrome (TTTS) is a condition wherein monochorionic twins share a common placenta with placental anastomoses between the two foetal circulations. Most infants who survive TTTS are born prematurely. This study aimed to determine whether fetoscopic laser ablation (FLA) can reduce the risk of retinopathy of prematurity (ROP) and whether TTTS was a risk factor for ROP. METHODS: This single-centre, retrospective, comparative study included 32 monochorionic twins with TTTS matched for gestational age, birthweight and sex to premature twins and singletons without TTTS (n = 68; twins, n = 34; and singletons, n = 34) born between 2003 and 2022. A single ophthalmologist recorded the fundus findings. FLA was performed using Solomon's technique to separate the vascular systems of the twins with TTTS. RESULTS: The gestational age and weight of premature infants with TTTS treated with FLA were significantly higher than those of untreated infants (p = 0.001 and p = 0.001, respectively); however, the hyaline membrane grade was lower (p = 0.004). A significant increase in weight (g/day) (p = 0.002) and lesser avascular area in the peripheral temporal retina (p = 0.045) was observed at postnatal week 4. The risk of ROP in the FLA group was 2.6 times (13.3% vs. 35.3%) lower than that in the non-FLA group; however, this difference was not significant. The incidence of any stage of ROP (25% vs. 18%) and treatment for ROP type 1 (6.25% vs. 5.9%) did not differ significantly between monochorionic twins with TTTS and premature infants without TTTS. CONCLUSION: The gestational age of premature infants with TTTS treated with FLA was higher than that of untreated infants. Moreover, a reduction in complications of prematurity was also observed. Laser fetoscopy in twin-twin transfusion syndrome may reduce the risk of ROP, but the difference was not statistically significant in this small study.


Asunto(s)
Transfusión Feto-Fetal , Fetoscopía , Edad Gestacional , Terapia por Láser , Retinopatía de la Prematuridad , Humanos , Transfusión Feto-Fetal/cirugía , Femenino , Retinopatía de la Prematuridad/cirugía , Retinopatía de la Prematuridad/diagnóstico , Estudios Retrospectivos , Embarazo , Fetoscopía/métodos , Recién Nacido , Masculino , Terapia por Láser/métodos , Factores de Riesgo , Incidencia , Peso al Nacer
4.
BMC Nurs ; 22(1): 236, 2023 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-37420220

RESUMEN

BACKGROUND: 'Learning by doing' is a learning model based on performing actions and gaining experience. The 'nursing process' is a systematic, rational method for providing nursing care. During their university education, nursing students need to acquire the ability to promote healthy lifestyles. OBJECTIVE: To determine the effectiveness of a learning strategy based on learning by doing and grounded in the use of the nursing process, on the lifestyle of nursing students. METHODS: This quasi-experimental intervention (before-after), performed over 2011-2022, involved 2300 nursing students at a university nursing school in Spain. The risk factors for chronic diseases-being a smoker, being overweight, or having high blood pressure-to which each student was exposed were recorded. Those positive for at least one risk factor selected companion students as 'support nursing students' who became responsible for designing an individualised care plan to reduce the risk(s) faced. To ensure the correct use of the nursing process, teachers approved and monitored the implementation of the care plans. Whether risk-reduction objectives were met was determined three months later. RESULTS: The students with risk factors largely improved their lifestyles (targets for reducing smoking/body weight were met) with the help of their supporting peers. CONCLUSIONS: The learning by doing method demonstrated its effectiveness, improving the lifestyle of at-risk students via the use of the nursing process.

5.
J Flow Chem ; : 1-18, 2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-37359287

RESUMEN

Nucleosides modification via conventional cross-coupling has been performed using different catalytic systems and found to take place via long reaction times. However, since the pandemic, nucleoside-based antivirals and vaccines have received widespread attention and the requirement for rapid modification and synthesis of these moieties has become a major objective for researchers. To address this challenge, we describe the development of a rapid flow-based cross-coupling synthesis protocol for a variety of C5-pyrimidine substituted nucleosides. The protocol allows for facile access to multiple nucleoside analogues in very good yields in a few minutes compared to conventional batch chemistry. To highlight the utility of our approach, the synthesis of an anti-HSV drug, BVDU was also achieved in an efficient manner using our new protocol. Supplementary Information: The online version contains supplementary material available at 10.1007/s41981-023-00265-1.

6.
Sci Total Environ ; 884: 163847, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37127158

RESUMEN

The use of apicultural matrices for the environmental monitoring of pesticides is a widely employed approach that facilitates to a great extent the sampling procedures. Honey bees are one of the most commonly employed matrices in these studies due to their abundance in the colonies and their direct contact with the beehive and the environment. However, the analysis of this matrix is associated to a lack of representativity of the contaminants accumulated within the beehive, due mainly to the limited number of honey bees that are sampled and analyzed compared to the population in a hive. This small proportion of organisms which are sampled from the colony may lead to underestimations or overestimations of the total pesticide load, depending on the specific individuals that are included in the analysis. In the present work, the passive, non-invasive APIStrip-based sampling approach is compared to active bee sampling with a total of 240 samples taken from 15 apiaries from Austria, Denmark and Greece over a two-month period in 2022. The APIStrips have been found to provide a more comprehensive image of the pesticide residues accumulated in the beehive in terms of number of identified residues and robustness of the results. A total of 74 different pesticide residues were detected: the use of APIStrips allowed to detect 66 pesticides in the three countries, compared to 38 residues in honey bees. The use of APIStrips also resulted in a higher percentage of positive samples (containing at least one pesticide residue). The results provided by the passive sampling approach were also more consistent among the replicates and over time, which reveals an increased sampling robustness.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Abejas , Animales , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Apicultura , Monitoreo del Ambiente/métodos , Austria
7.
Diabetes Res Clin Pract ; 199: 110650, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37015259

RESUMEN

BACKGROUND: Metabolic surgery is the most effective therapeutic strategy for the management of type 2 diabetes (T2DM). Several preoperative clinical factors have been associated with T2DM remission after metabolic surgery. However, other potential predictors remain unexplored. AIM: To assess the role of basal (pre-surgery) clinical and biochemical parameters in T2DM remission after metabolic surgery. METHODS: A prospective study including 98 patients with T2DM undergoing metabolic surgery was performed. Clinical, anthropometric, and biochemical data were collected at baseline and 1 year following metabolic surgery. RESULTS: Patients without T2DM remission 1 year after metabolic surgery presented a longer duration of diabetes and higher glycated hemoglobin (HbA1c) levels; a higher percentage of these subjects were using insulin therapy, antihypertensive drugs, and lipid-lowering therapies before metabolic surgery, compared to those patients with T2DM remission. A lower percentage of T2DM remission after metabolic surgery was observed among patients with hypertension/hypercholesterolemia before surgery, compared to those patients without hypertension/hypercholesterolemia (51.7 % vs 86.8 %, p < 0.001, and 38.5 % vs 75 %, p < 0.001, respectively), and among patients with longer duration of diabetes (≥5 years vs <5 years; 44.4 % vs 83 %, respectively; p < 0.001). In the logistic regression model, diabetes duration, basal HbA1c, and the presence of hypertension and hypercholesterolemia before surgery were inversely related to T2DM remission following metabolic surgery, after adjusting for sex, age, waist circumference, and type of surgery. CONCLUSIONS: In a cohort of patients with obesity and T2DM, preoperative hypertension and hypercholesterolemia, together with a longer diabetes duration and higher HbA1c concentrations, were independent predictors of T2DM persistence after metabolic surgery.


Asunto(s)
Cirugía Bariátrica , Diabetes Mellitus Tipo 2 , Hipercolesterolemia , Hiperlipidemias , Hipertensión , Obesidad Mórbida , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/cirugía , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada , Estudios Prospectivos , Glucemia/metabolismo , Hipertensión/complicaciones , Inducción de Remisión , Resultado del Tratamiento , Obesidad Mórbida/complicaciones
8.
ACS Appl Polym Mater ; 5(1): 381-390, 2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36686062

RESUMEN

The rampant evolution of resistance in Plasmodium to all existing antimalarial drugs calls for the development of improved therapeutic compounds and of adequate targeted delivery strategies for them. Loading antimalarials in nanocarriers specifically targeted to the parasite will contribute to the administration of lower overall doses, with reduced side effects for the patient, and of higher local amounts to parasitized cells for an increased lethality toward the pathogen. Here, we report the development of dendronized hyperbranched polymers (DHPs), with capacity for antimalarial loading, that are coated with heparin for their specific targeting to red blood cells parasitized by Plasmodium falciparum. The resulting DHP-heparin complexes exhibit the intrinsic antimalarial activity of heparin, with an IC50 of ca. 400 nM, added to its specific targeting to P. falciparum-infected (vs noninfected) erythrocytes. DHP-heparin nanocarriers represent a potentially interesting contribution to the limited family of structures described so far for the loading and targeted delivery of current and future antimalarial compounds.

9.
Acta Ophthalmol ; 101(3): e294-e301, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36217834

RESUMEN

AIM: The aim of the study was to assess the influence of blood product transfusions on the development and severity of retinopathy of prematurity (ROP). METHODS: A retrospective cohort study was conducted of very low birth weight (VLBW) newborns with less than 32 weeks gestational age (GA) admitted to the neonatal unit of a tertiary care hospital during the period from 1 January 2008 to 31 December 2021. Data on the degree of ROP and the transfusions received were obtained and analysed. Both univariate and multivariate analyses were performed, by logistic regression. RESULTS: A total of 565 VLBW newborns were recruited, of whom 263 received a red blood cell transfusion prior to 36 weeks corrected GA. The newborns with ROP received significantly more red blood cell transfusions than those not presenting this condition. After adjusting for oxygen therapy and GA, the risk of ROP was found to be 2.77 times higher (95% CI 1.31-5.88) after receiving three or more transfusions, with a 3.95 times higher risk (95% CI 1.40-11.1) of developing severe ROP. Having received the first red blood cell transfusion before 32 weeks corrected GA is associated with an increased risk of ROP (OR 2.18; 95% CI: 1.09-4.36). CONCLUSION: In VLBW neonates, the number of red blood cell transfusions and their administration before 32 weeks corrected GA are important risk factors for ROP.


Asunto(s)
Recien Nacido Prematuro , Retinopatía de la Prematuridad , Recién Nacido , Humanos , Estudios de Cohortes , Estudios Retrospectivos , Retinopatía de la Prematuridad/diagnóstico , Retinopatía de la Prematuridad/epidemiología , Retinopatía de la Prematuridad/etiología , Recién Nacido de muy Bajo Peso
10.
Am J Perinatol ; 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36451626

RESUMEN

OBJECTIVE: This article describes the results of a study investigating the sensitivity and specificity of the Newborn Infant Parasympathetic Evaluation (NIPE) index for detecting the physiological changes resulting from nociception in painful procedures in very low birth weight (VLBW) infants. STUDY DESIGN: A prospective observational study was carried on of 44 newborns at 23 to 32 weeks' gestational age. The sensitivity and specificity of the NIPE index are analyzed using a receiver operating characteristic curve. Most of the painful procedures performed were skin-lancing and venipunctures. Nonpainful procedures consist of no intervention, with an interval of at least 1 hour with painful procedures in each newborn. RESULTS: The accuracy of the NIPE index to diagnose mild nociceptive stimulation in VLBW newborns is 73.2%. CONCLUSION: The NIPE index is a useful technique for assessing nociceptive stimulation in newborns, presenting less observer-dependent variability than other pain assessment scales. KEY POINTS: · The NIPE index offers an objective assessment of pain.. · Moderate-high sensitivity of the NIPE index in the evaluation of pain in premature newborns.. · Painful procedures in VLBW newborns are reflected as a decrease in the NIPE score..

11.
Nanomaterials (Basel) ; 12(22)2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36432312

RESUMEN

A series of six polybenzylic dendrons with an alkynyl focal point were synthesized for their incorporation to gold nanoparticles. Five of these compounds showed columnar mesomorphism in a wide range of temperatures. These dendrons were reacted with gold nanoparticles stabilized with a combination of a dodecanethiol and 11-azidoundecane-1-thiol. The azido group of the last compound allowed the functionalization of the nanoparticles with the six polybenzylic dendrons by 1,3-dipolar cycloaddition between their alkynyl groups and the terminal azido groups of the thiols. A high efficiency of the cycloaddition process (47-69%) was confirmed by several experimental techniques and no decomposition or aggregation phenomena were detected in the dendron-coated nanoparticles. The involved mechanism and the resulting percentage composition of the final materials are discussed. The results of the ulterior growth of the nanoparticles by thermal treatment are influenced by the size and the shape of the dendron and the temperature of the process. The structures of the final nanoparticles were investigated by TEM, DSC, TGA, NMR and UV-Vis spectroscopy. These nanoparticles do not show liquid crystal properties. However, a melting process between a crystalline and a fluid phase is observed. In the solid phase, the nanomaterials prepared show a short-range interaction between nanoparticles with a 2D local hexagonal order. A near-field effect was observed in the UV-vis spectra by coupling of different surface plasmon resonance bands (SPR) probably due to the short-range interactions. The main novelty of this work lies in the scarcity of previous studies of gold nanoparticles coated with dendrons forming themselves columnar mesophases. Most of the studies reported in the literature deal with gold nanoparticles coated with calamitic mesogens. Additionally, the effect of the thermal treatment, which in a previous paper was shown to increase the mean size of the nanoparticles without increasing their size polydispersity, has been studied in these materials.

12.
Biology (Basel) ; 11(7)2022 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-36101440

RESUMEN

(1) Background: This study was conducted to investigate the effects of a 10-week neuromuscular training program (NMT) on the sum of six skinfolds (Σ6S) and body composition variables in elite female soccer players. (2) Methods: Forty-four Spanish elite female soccer players (age: 24.0 ± 4.2 years; height: 164.3 ± 5.5 cm; body mass: 60.4 ± 5.5 kg; body mass index (BMI): 22.4 ± 2.2 kg/m2) were randomly assigned to a control group (CG) or to an experimental group (EG). Participants in the EG completed a specific NMT program of 24 min, three times per week, which included exercises from six different categories (mobility, dynamic stability, anterior chain strength, lumbopelvic control, posterior chain strength, and change of direction). The CG followed their normal strength and conditioning program. Pre- and post-intervention assessments included anthropometric measurements (weight, height, limb circumferences, and bone breadths), and subsequently, body composition factors BMI, Σ6S, body mass, muscle mass, and lean body mass were calculated. Nutrition was standardized by a nutritionist and also load monitored. (3) Results: A two-way mixed analysis of variance (group × time) revealed that there was a significant (p ≤ 0.001) group × time interaction between body mass, fat mass, and Σ6S in favor of NMT. A significant interaction was also observed for body skeletal muscle mass and lean body mass favoring NMT. (4) Conclusions: The application of an NMT program seems to be a useful strategy to improve body composition in elite female soccer players.

13.
Chem Rec ; 22(12): e202200179, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36094784

RESUMEN

Modification of unprotected nucleosides has been attracting continuous interest, since these building blocks themselves and their phosphate-upgraded corresponding nucleotides have shown a plethora of uses in fields like biochemistry or pharmacy. Pd-catalyzed cross-coupling reactions, conducted in water or its mixtures with polar organic solvents, have frequently been the researchers' choice for the functionalization of the purine/pyrimidine base of the unprotected nucleosides. In this scenario, the availability of hydrophilic ligands and its water-soluble palladium complexes has markedly set the pace of the advances. The approach of our group to the synthesis of such complexes, Pd-imidates specifically, has faced critical stages, namely the jump to synthesize water soluble complexes from our experience working in conventional solvents, the preparation of phosphine free complexes and the overall goal of getting catalytic systems able to work close to room temperature. The continuous feedback with Kapdi's group, experienced in the chemistry of nucleosides, has produced over the last decade the interesting results in both fields presented here.


Asunto(s)
Paladio , Agua , Agua/química , Catálisis , Paladio/química , Nucleósidos , Solventes/química
14.
Biomater Sci ; 10(10): 2706-2719, 2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35441621

RESUMEN

Gene therapy has become a relevant tool in the biomedical field to treat or even prevent some diseases. The effective delivery of genetic material into the cell remains a crucial step to succeed in this purpose. In the search for efficient non-viral vectors, a series of amino-terminated dendronized hyperbranched polymers (DHPs) of different generations based either on bis-MPA or bis-GMPA have been designed. All of them have demonstrated an accurate ability to complex two types of genetic materials, a plasmid DNA and a siGFP, yielding dendriplexes. Moreover, some of them have proved to be able to deliver the genetic material inside the cells, resulting in the effective accomplishment of the desired genetic modification and improving the activity of some commercial transfection reagents. Different cell lines, including cancer and mesenchymal stem cells, have been studied here to evaluate the ability of DHPs as vectors for transfection. Treatments based on mesenchymal stem cells are gaining importance due to their pluripotency. Thus, it is of special relevance to introduce a genetic modification into a mesenchymal cell line as it allows it to act over a wide spectrum of tissues after inducing cellular differentiation.


Asunto(s)
Dendrímeros , Poliésteres , Línea Celular , Técnicas de Transferencia de Gen , Terapia Genética , Vectores Genéticos/genética , Polímeros , Transfección
15.
Dalton Trans ; 51(6): 2370-2384, 2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-35043803

RESUMEN

Commercially available Quadrol, N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine (THPEN), has been used for the first time as a N^N-donor neutral hydrophilic ligand in the synthesis and characterization of new water soluble palladium(II) complexes containing chloride, phthalimidate or saccharinate as co-ligands. [PdCl2(THPEN)] (1) [Pd(phthal)2(THPEN)] (2), [Pd(sacc)2(THPEN)] (3) and the analogous complex with the closely related N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine (THEEN) [Pd(sacc)2(THEEN)] (4) were efficiently prepared in a one-pot reaction from [PdCl2(CH3CN)2] or Pd(OAc)2. Structural characterization of 1 and 3 by single crystal X-ray diffraction produced the first structures reported to date of palladium complexes with Quadrol. The resultant palladium complexes are highly soluble in water and were found to be effective as phosphine-free catalysts for the synthesis of functionalized nucleoside analogues under room-temperature Suzuki-Miyaura cross-coupling conditions between 5-iodo-2'-deoxyuridine (& 5-iodo-2'-deoxycytidine) with different aryl boronic acids in neat water. This is the first report of the coupling process performed on nucleosides in water at room temperature.


Asunto(s)
Etilenodiaminas
16.
BMC Sports Sci Med Rehabil ; 13(1): 157, 2021 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-34915917

RESUMEN

BACKGROUND: The aim of this study was to analyse the physical demands and technical-tactical actions for each playing position according to game location and final outcome in professional soccer players. METHODS: A convenience sample was obtained from twenty-one professional male soccer players, belonged to same soccer team of the Spanish Second Division. Players' physical demands were monitored during each match using a portable 18 Hz GPS unit and 600 Hz triaxial accelerometer. These analysed demands were total distance, moderate speed running distance (>14.4 km·h-1), high-speed running distance (>19.8. km·h-1), sprint distance (>25.0 km·h-1), number of accelerations between 2 and 4 m·s-2 and above 4 m·s-2, and number of decelerations between 2 and 4 m·s-2 and above 4 m·s-2. The data related to technical-tactical actions were obtained from WyScout®, a computerized multiple-camera tracking system based on the OPTA® track analysis tool. The obtained indicators were general, defensive and offensive. RESULTS: For all players, higher total distance (p = 0.045; effect size [ES] = 0.24, small effect) was covered and greater deceleration 2-4 m·ss-2 (p = 0.001; ES = 0.68, medium effect) was performed when the team plays at home and lose and for all players, playing at home and winning demanded higher defensive volume (p =0.014; ES = - 1.49, large effect) and nº interceptions (p =0.031; ES = - 1.40, large effect) in comparison to playing at home and losing. CONCLUSIONS: The physical demands and technical-tactical actions vary when contextual game factors (i.e., match location and final outcome) are considered. We can confirm that, although the training of physical demands does not influence the final result of the match, the training of technical tactical actions could help to achieve an optimal performance of the team to win matches.

17.
Sports (Basel) ; 9(12)2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34941796

RESUMEN

BACKGROUND: This study compared the effects of performing different unilateral combined training interventions on diverse vertical and horizontal jumping performance parameters, change of direction, concentric and eccentric mean power, and their associated inter-limb asymmetries in young soccer players. METHODS: Forty-seven young male soccer players (age: 15.5 ± 0.9 years) were distributed into three groups. Two groups performed the same training volume with both legs, beginning with the weaker leg (Stronger Volume Weaker leg group (SVW), n = 14) or with the stronger leg (Stronger Volume Stronger leg group, (SVS), n = 15). The third group executed double the volume with the weaker leg and also commenced with such leg (Double Volume Weaker leg group (DVW), n = 16) during a 10-week period. Pre- and post-intervention tests included a single-leg hop, single-leg lateral hop, triple hop, bilateral and unilateral countermovement jumps, a change of direction speed test, concentric and eccentric mean power during the lateral squat test, and their corresponding asymmetries. RESULTS: Single-leg hop weaker leg, triple hop weaker leg, and bilateral countermovement jump improvements were achieved in the SVW (ES: 0.29 to 0.46) and DVW (ES: 0.55 to 0.73) groups. Between-groups analysis showed better results in single-leg hop in the SVW and DVW compared to group SVS. The DVW group achieved better improvements in countermovement jump in comparison to groups SVS and SVW. CONCLUSIONS: Groups that started with the weaker leg seemed to achieve a greater volume of significant changes than when starting with the stronger leg. Performing a double volume on the weaker limb does not guarantee further improved performance compared to other groups.

19.
Artículo en Inglés | MEDLINE | ID: mdl-34444018

RESUMEN

BACKGROUND: The present study compared the effects of performing the lateral squat exercise in three different formats from eccentric overload training on concentric/eccentric peak/mean power and inter-limb asymmetries in young soccer players. METHODS: Forty-five young male (U-17) soccer players were distributed into three groups. Two groups performed the same training volume with both legs, beginning with the weaker leg (SVW, n = 15) or with the stronger leg (SVS, n = 15). The third group executed double volume with the weaker leg and also commenced with such leg (DVW, n = 15) in the lateral squat during a 10-week period. Pre- and post-intervention metrics included concentric and eccentric peak/mean power during the lateral squat test and their corresponding asymmetries. RESULTS: All groups improved all power variables. Concentric mean and peak power asymmetry were substantially reduced in the SVW (ES: 0.89), DVW (ES: 0.43), and in SVW (ES: 1.60). Eccentric mean and peak power asymmetry were also substantially decreased in SVW (ES: 0.81) and in DVW (ES: 0.68). Between-group analyses showed substantially better performance in concentric and eccentric variables with stronger and weaker legs in SVW and DVW groups compared with SVS. CONCLUSIONS: Those groups which started with the weaker leg showed greater both power enhancements and reductions on inter-limb asymmetries.


Asunto(s)
Rendimiento Atlético , Entrenamiento de Fuerza , Fútbol , Adolescente , Ejercicio Físico , Humanos , Pierna , Masculino , Fuerza Muscular
20.
Int J Mol Sci ; 22(11)2021 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-34072169

RESUMEN

Highly functional macromolecules with a well-defined architecture are the key to designing efficient and smart materials, and these polymeric systems can be tailored for specific applications in a diverse range of fields. Herein, the formation of a new liquid crystalline polymeric network based on the crosslinking of dendrimeric entities by the CuI-catalyzed variant of the Huisgen 1,3-dipolar cycloaddition of azides and alkynes to afford 1,2,3-triazoles is reported. The polymeric material obtained in this way is easy to process and exhibits a variety of properties, which include mesomorphism, viscoelastic behavior, and thermal contraction. The porous microstructure of the polymer network determines its capability to absorb solvent molecules and to encapsulate small molecules, like organic dyes, which can be released easily afterwards. Moreover, all these properties may be easily tuned by modifying the chemical structure of the constituent dendrimers, which makes this system a very interesting one for a number of applications.


Asunto(s)
Dendrímeros/química , Cristales Líquidos/química , Polímeros/química , Algoritmos , Fenómenos Químicos , Técnicas de Química Sintética , Cristales Líquidos/ultraestructura , Fenómenos Mecánicos , Modelos Teóricos , Estructura Molecular , Difracción de Rayos X
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