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Gold nanoparticles (AuNPs) are functionalized with a thermoresponsive polymer shell of a cross-linked poly(2-(2-methoxyethoxy)ethyl methacrylate) (P(MEO2MA)). To provide a covalent attachment of the polymer to the NP surface, AuNPs are first modified using butanoic acid to develop the encapsulation with the biocompatible thermoresponsive polymer formed by free-radical precipitation polymerization. Both the MEO2MA concentration and the shell cross-linking density can be varied and, in turn, the thickness and the shells' free volume can be fine-tuned. By downscaling the size of the polymeric shell, the lower critical solution temperature (LCST) is decreased. The LCST in the nanohybrids changes from 19.1 to 25.6 °C when increasing the MEO2MA content; it reaches almost 26 °C for P(MEO2MA) (bulk). The maximum decrease in the volume of the nanohybrids is around 40%, resulting in a modification of the light scattering properties of the system and causing a change in the turbidity of the gel network. The sizes of the nanohybrids are characterized using both transmission electron microscopy and dynamic light scattering measurements. Optical properties of the colloidal systems are determined using the derived count rate measurements as an alternative to absorbance or transmittance measurements, confirming the colloidal stability of the nanohybrid systems. [ABSTRACT FROM AUTHOR]

Background: Type 2 diabetes mellitus is a metabolic disorder characterized by insulin resistance (IR), which is prevalent worldwide and has significant adverse health effects. Metformin is commonly prescribed as a pharmacological treatment. Physical exercise is also recognized as an effective regulator of glycemia, independent of metformin. However, the effects of inter-day concurrent training (CT)—which includes both endurance and resistance exercises—combined with metformin treatment on metabolic markers and cardiorespiratory fitness in individuals with IR remain controversial. Objective: This study aimed to analyze the effects of a 12-week inter-day CT program on metabolic markers and cardiorespiratory fitness in overweight/obese individuals with IR, both with and without metformin treatment. Additionally, inter-individual responses to CT were examined. Materials and Methods: Data from the 2022–2023 Obesity Center database were retrospectively analyzed. According to the eligibility criteria, 20 overweight/obese individuals diagnosed with IR participated in a 12-week CT program (three weekly sessions: two endurance and one resistance exercise session). Participants were divided into three groups: the exercise group (E-G: n = 7, 32.86 ± 8.32 years, 85.2 ± 19.67 kg), the exercise–metformin group (E-MG: n = 6, 34.83 ± 12.91 years, 88.13 ± 12.66 kg), and the metformin-only control group (M-G: n = 7, 34.43 ± 13.96 years, 94.23 ± 13.93 kg). The M-G did not perform physical exercise during the 12 weeks but continued pharmacological treatment. Body composition, metabolic markers, and cardiorespiratory fitness were assessed before and after the 12-week CT program. Results: A group-by-time interaction was observed for fasting insulin (F2,17 = 34.059, p < 0.001, η2p = 0.88), the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) (F2,17 = 35.597, p < 0.001, η2p = 0.80), and maximal fat oxidation (MFO) (F2,17 = 4.541, p = 0.026, η2p = 0.348) following the CT program. The maximal oxygen uptake (VO2max) showed significant improvements in the E-G (F = 4.888, p = 0.041, ∆+13.3%). Additionally, the percentage of fat mass (%FM) and body mass (BM) were significantly reduced across all groups (F = 125.244, p < 0.001 and F = 91.130, p < 0.001, respectively). The BM decreased by ∆−9.43% in the E-G (five responders, Rs), ∆+9.21% in the EM-G (5 Rs), and ∆+5.15% in the M-G (3 Rs). The %FM was reduced in the E-G by ∆−22.52% (seven Rs). Fasting insulin and the HOMA-IR significantly improved in both the E-G and EM-G, with fasting insulin showing a ∆−82.1% reduction in the E-G (five Rs) and a ∆−85% reduction in the EM-G (six Rs). Similarly, the HOMA-IR improved by ∆+82.6% in the E-G (three Rs) and by ∆+84.6% in the EM-G (six Rs). Conclusions: The 12-week inter-day concurrent training program, whether combined with metformin or not, was similarly effective in improving metabolic markers in patients with insulin resistance as metformin treatment alone. Both exercise groups demonstrated a significant reduction in insulin sensitivity and an increase in maximal fat oxidation. Meanwhile, exclusive pharmacological treatment with metformin markedly decreased cardiorespiratory fitness, and consequently, fat oxidation. [ABSTRACT FROM AUTHOR]

BACKGROUND: In taekwondo the ability to repeat high-intensity efforts is characteristic of the sport. The Frequency speed of kick test (FSKT) is frequently used to assess this ability, although its influence on aerobic capacity and dynamic strength characteristics has received less attention in the literature. OBJECTIVE: To examine the relationship between specific high-intensity intermittent efforts with aerobic capacity and slow stretch-shortening cycle utilization in taekwondo athletes. METHODS: Nineteen taekwondo male athletes were assessed by squat jump (SJ), countermovement jump (CMJ), 20-meter shuttle run (20MSR), and frequency speed of kick test multiple (FSKT MULT). From the FSKT MULT , total kicks and kick decrement index [KDI] were calculated. Additionally, from both jump tests, the slow stretch-shortening cycle utilization (Slow SSC Utilization) was determined from the eccentric utilization ratio [EUR], pre-stretch augmentation [PSA], and reactive strength index [RSI]. RESULTS: There were positive and significant correlations between total kicks with 20MSR (r = 0.85; p = 0.00) and SJ (r = 0.66; p < 0.05). The multiple regression model demonstrated that total kicks where significantly influenced by 20MSR ( R 2 = 71%; p = 0.00). Additionally, only EUR and RSI explained total kicks performance to a greater proportion ( R 2 = 76%). CONCLUSIONS: The FSKT MULT total kicks performance is positively correlated and influenced by aerobic capacity and slow SSC utilization. [ABSTRACT FROM AUTHOR]

BACKGROUND: Explosive strength and change of direction speed (CODS) are relevant physical abilities in karate. OBJECTIVE: To examine the relationship between the characteristics of explosive strength and the 5-m linear sprint (5M) with CODS performance and ii) to examine the influential characteristics of explosive strength on CODS performance. METHODS: Eighteen cadet and junior karate athletes, eight females and ten males were evaluated. The physical abilities assessments included: squat jump (SJ), countermovement jump (CMJ), 5M and CODS. Also, pre-stretch percentage increase (PSA), eccentric utilization index (EUR) reactive strength index (RSI) were calculated. RESULTS: Superior performance (p < 0.05) was documented in SJ, CMJ and CODS in male vs. female. Also, significant correlations between CODS with SJ and CMJ (r = - 0.70 to - 0.80; R 2 = - 0.51 to - 0.73; p < 0.05, respectively) and correlations (r = - 0.14 to - 0.22; R 2 = 0.01 to 0.04; p > 0.05) between CODS with RSI, EUR and PSA. Multiple regression model documented that only SJ significantly influenced CODS performance in male ( R 2 = 60%; p = 0.009) and female ( R 2 = 71%; p = 0.001). CONCLUSION: CODS correlate with SJ and CMJ. In particular, SJ influence CODS independently of gender. [ABSTRACT FROM AUTHOR]

BACKGROUND: Explosive strength and change of direction speed (CODS) are relevant physical abilities in karate. OBJECTIVE: To examine the relationship between the characteristics of explosive strength and the 5-m linear sprint (5M) with CODS performance and ii) to examine the influential characteristics of explosive strength on CODS performance. METHODS: Eighteen cadet and junior karate athletes, eight females and ten males were evaluated. The physical abilities assessments included: squat jump (SJ), countermovement jump (CMJ), 5M and CODS. Also, pre-stretch percentage increase (PSA), eccentric utilization index (EUR) reactive strength index (RSI) were calculated. RESULTS: Superior performance (p < 0.05) was documented in SJ, CMJ and CODS in male vs. female. Also, significant correlations between CODS with SJ and CMJ (r = - 0.70 to - 0.80; R 2 = - 0.51 to - 0.73; p < 0.05, respectively) and correlations (r = - 0.14 to - 0.22; R 2 = 0.01 to 0.04; p > 0.05) between CODS with RSI, EUR and PSA. Multiple regression model documented that only SJ significantly influenced CODS performance in male ( R 2 = 60%; p = 0.009) and female ( R 2 = 71%; p = 0.001). CONCLUSION: CODS correlate with SJ and CMJ. In particular, SJ influence CODS independently of gender. [ABSTRACT FROM AUTHOR]

Resumen Objetivos Desarrollar recomendaciones sobre la actividad física y el ejercicio para pacientes con espondiloartritis (EspA) basadas en la opinión de expertos. Métodos Dos grupos de expertos, uno de fisioterapeutas, rehabilitadores y profesionales de la actividad física y deporte y otro de reumatólogos con interés en EspA, se reunieron para discutir los resultados de grupos focales con pacientes sobre barreras al ejercicio y de una encuesta a reumatólogos sobre ejercicio en EspA. A continuación se redactaron unas recomendaciones preliminares que fueron sometidas a la opinión de los expertos de ambos grupos mediante metodología Delphi a dos rondas. Resultados Se emitieron 21 recomendaciones que cubren el ejercicio físico, la adaptación al paciente, el modo de dar los mensajes, el manejo del dolor, el tipo de ejercicios indicado y el seguimiento. El grado de acuerdo varía ligeramente entre los grupos de expertos pero en general fue alto. Los ítems discordantes o con poco acuerdo fueron eliminados del consenso. Conclusiones Se han emitido recomendaciones sobre cuándo y cómo prescribir ejercicio físico y monitorizarlo en pacientes con EspA basadas en la opinión de expertos en espondilitis y en la prescripción de ejercicio. Deberemos confirmar si estas recomendaciones son útiles para la práctica clínica y tienen efecto en los pacientes con EspA atendidos por reumatólogos. Abstract Objective To develop expert-based recommendations on physical activity and exercise for patients with spondyloarthritis (SpA). Methods Two discussion groups, one of physical therapists, rehabilitation physicians, and professionals of physical activity and sports, and another of rheumatologists interested in SpA, were held to discuss the results of a survey of rheumatologists on exercise and two focus groups with patients on barriers to exercise. Preliminary recommendations were drafted. These were submitted to the opinion of the experts in both groups according to a two round Delphi methodology. Results Twenty one recommendations covering general aspects of exercise, adaptation to patient, how to deliver messages, pain management, and type of exercise and monitoring were issued. The level of agreement varied slightly between expert groups but it was high overall. Items with poor agreement were removed from the consensus. Conclusions We present recommendations on when and how to prescribe and monitor exercise in patients with SpA based on the opinion of experts in exercise and in SpA. We must now test whether these recommendations are useful for clinical practice and have an effect on patients with SpA seen by rheumatologists. [ABSTRACT FROM AUTHOR]