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1.
Int J Biol Macromol ; 269(Pt 1): 132108, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38710258

ABSTRACT

Natural and synthetic biodegradable polymers are widely used to obtain more sustainable films with biological, physicochemical, and mechanical properties for biomedical purposes. The incorporation of essential oils (EOs) in polymeric films can optimize the biological activities of these EOs, protect them from degradation, and serve as a prototype for new biotechnological products. This article aims to discuss updates over the last 10 years on incorporating EOs into natural and synthetic biodegradable polymer films for biomedical applications. Chitosan, alginates, cellulose, and proteins such as gelatine, silk, and zein are among the natural polymers most commonly used to prepare biodegradable films for release EOs. In addition to these, the most cited synthetic biodegradable polymers are poly(L-lactide) (PLA), poly(vinyl alcohol) (PVA), and poly(ε-caprolactone) (PCL). The EOs of clove, cinnamon, tea tree, eucalyptus, frankincense, lavender, thyme and oregano incorporated into polymeric films have been the most studied EOs in recent years in the biomedical field. Biomedical applications include antimicrobial activity against pathogenic bacteria and fungi, anticancer activity, potential for tissue engineering and regeneration with scaffolds and wound healing as dressings. Thus, this article reports on the importance of incorporating EOs into biodegradable polymer films, making these systems especially attractive for various biomedical applications.

2.
Adapt Phys Activ Q ; : 1-14, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38648885

ABSTRACT

The journey of Brazilian female Paralympians transcends mere statistical increases in women's participation. Behind the modest athlete growth lies the reality of women who are doubly marginalized by the intersection of gender and disability in an arena tailored for able-bodied men. Our study aimed to catalyze critical discourses surrounding the historical trajectory of Paralympic women's sports. Through a comprehensive documentary analysis based on the Brazilian Paralympic Committee's official documents from 1976 to 2021, we sought to shed light on this complex scenario. Numerically, Brazil's representation comprised 229 women who, predominantly, had physical impairments and engaged in individual sports. In addition to a sporting legacy deeply entrenched in physical rehabilitation with limited opportunities for team-based sports, we observed negative influences stemming from ableist and sexist narratives. A thorough investigation into Paralympic milestones revealed a multitude of social barriers and highlighted the significant impact of societal changes in reshaping athletic opportunities and challenging traditional stereotypes.

3.
Adv Mater ; : e2313961, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38593210

ABSTRACT

The advent of covalent adaptable networks (CANs) through the incorporation of dynamic covalent bonds has led to unprecedented properties of macromolecular systems, which can be engineered at the molecular level. Among the various types of stimuli that can be used to trigger chemical changes within polymer networks, light stands out for its remote and spatiotemporal control under ambient conditions. However, most examples of photoactive CANs need to be transparent and they exhibit slow response, side reactions, and limited light penetration. In this vein, it is interesting to understand how molecular engineering of optically active dynamic linkages that offer fast response to visible light can impart "living" characteristics to CANs, especially in opaque systems. Here, the use of carbazole-based thiuram disulfides (CTDs) that offer dual reactivity as photoactivated reshuffling linkages and iniferters under visible light irradiation is reported. The fast response to visible light activation of the CTDs leads to temporal control of shape manipulation, healing, and chain extension in the polymer networks, despite the lack of optical transparency. This strategy charts a promising avenue for manipulating multifunctional photoactivated CANs in a controlled manner.

4.
ACS Sens ; 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38639453

ABSTRACT

Noninvasive monitoring of biofabricated tissues during the biomanufacturing process is needed to obtain reproducible, healthy, and functional tissues. Measuring the levels of biomarkers secreted from tissues is a promising strategy to understand the status of tissues during biofabrication. Continuous and real-time information from cultivated tissues enables users to achieve scalable manufacturing. Label-free biosensors are promising candidates for detecting cell secretomes since they can be noninvasive and do not require labor-intensive processes such as cell lysing. Moreover, most conventional monitoring techniques are single-use, conducted at the end of the fabrication process, and, challengingly, are not permissive to in-line and continual detection. To address these challenges, we developed a noninvasive and continual monitoring platform to evaluate the status of cells during the biofabrication process, with a particular focus on monitoring the transient processes that stem cells go through during in vitro differentiation over extended periods. We designed and evaluated a reusable electrochemical immunosensor with the capacity for detecting trace amounts of secreted osteogenic markers, such as osteopontin (OPN). The sensor has a low limit of detection (LOD), high sensitivity, and outstanding selectivity in complex biological media. We used this OPN immunosensor to continuously monitor on-chip osteogenesis of human mesenchymal stem cells (hMSCs) cultured 2D and 3D hydrogel constructs inside a microfluidic bioreactor for more than a month and were able to observe changing levels of OPN secretion during culture. The proposed platform can potentially be adopted for monitoring a variety of biological applications and further developed into a fully automated system for applications in advanced cellular biomanufacturing.

5.
Percept Mot Skills ; : 315125241247859, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38669451

ABSTRACT

Improvements in race times for male and female Para canoe athletes across different sports classes have led to a reduction in relative differences between classes over time. However, there is a lack of research examining the comparative developmental trajectories between high-performance Paralympic (PCS) and Olympic (OCS) canoe sprint. In this study, we compared the developmental trajectories of 200-meter kayak performances among PCS and OCS athletes. In total, we analyzed 628 race results obtained from public online databases, for nine competitions between 2015 and 2023. Race times were reduced over the years except in specific sports classes (KL3-M, K1-M, and K1-F; KL: Kayak Level, M: male, F: female), with a poor positive correlation (r = 0.17 to 0.33) between time and the years. For the remaining sports classes, these correlations ranged from poor to fair (r = -0.58 to -0.13). OCS K1 athletes outperformed their Paralympic counterparts. Among Paralympic classes, KL1 had slower times than KL2 and KL3 (p ≤ .05), with KL2 times significantly lower than KL3 in the female category. OCS athletes exhibited less variability in race times compared to PCS athletes. In the male category, there were no significant differences in the coefficients of variation (CV) and amplitude of race times between sport classes, except for KL1-M, which had a larger CV than K1 (p ≤ .05). In the female category, the CV and amplitude of race times were significantly higher in KL1-F compared to KL3-F and K1-F. OCS times remained stable from 2015, with KL3-M following a similar trend. PCS displayed greater race time variability, particularly in higher impairment classes, notably KL1. This underscores the existence of distinct developmental stages within the canoe sprint modality, particularly emphasizing the early developmental phase of KL1. It also provides valuable insights for coaches and sports selection, especially concerning athletes with more severe impairments, including those in Rehabilitation Centers and during athlete recruitment.

6.
Front Public Health ; 12: 1335311, 2024.
Article in English | MEDLINE | ID: mdl-38577282

ABSTRACT

Introduction: The use of normative values and/or standards of functional fitness in adults is relevant to overall health and well-being. The objectives of the study were: to identify the physical tests of the senior fitness test (SFT) that have been applied since its proposal and to describe the proposed percentiles according to age, sex and country. Methods: A systematic review study was conducted in the Pubmed and Scopus databases. As eligibility criteria, we considered the period from 1999 to 2022 that presented data on SFT test used in the population over 60 years of age and that described normative values through percentiles. MeSH were used as: (1) Physical fitness, Exercise test, Senior Fitness Test, Functional fitness, Cardiorespiratory fitness, (2) older adult, aged, (3) Reference standards, standards, standards of care. Boolean operators "AND" and "OR" were included. Data extracted from the selected studies included: year of publication, country, sample age, sample size, sample sex, fitness component. Results and discussion: Seven studies were identified in five countries (03 in China, 01 in Poland, 01 in Portugal, 01 in Spain and 01 in United States). The age range ranged from 60 to 103 years. The studies were conducted in both sexes. The study with the smallest sample size was by Chung et al. (China) with 944 participants and the largest number of participants was the study by Rikli and Jones in the United States with 7,183 participants. In general, no study was able to complete 100% (8 components) of the tests proposed in the SFT. Normative values were presented through percentile distribution (p10, p50 and p90) organized by age ranges. Males presented better performance in FPF tests than females in all tests. Since the first publication of the SFT until 2022, seven articles have been published in countries such as United States, China (three regional studies), Poland, Portugal and Spain. No study has published the complete battery with its eight components. The percentiles of functional fitness reflect decline with advancing age. Systematic review registration: PROSPERO (CRD42023441294: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023441294).


Subject(s)
Cardiorespiratory Fitness , Physical Fitness , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Exercise , Exercise Test/methods
7.
Nutr. clín. diet. hosp ; 44(2): 67-74, Abr. 2024. tab, graf
Article in Spanish | IBECS | ID: ibc-VR-1

ABSTRACT

Introducción: La evaluación del crecimiento físico y la aptitud física es considerada una tarea beneficiosa para la salud y del rendimiento deportivo. Objetivo: Comparar el crecimiento físico y la aptitud física de jóvenes nadadores y no-nadadores de una región del Perú. Metodología: Se efectuó un estudio descriptivo (comparativo) en niños y adolescentes de 6 a 13 años. Se conformó dos grupos de estudio. Grupo 1: Practicantes de natación (nadadores) y Grupo 2: No-practicantes de natación (no-nadadores). Se evaluó las medidas antropométricas de peso, estatura, circunferencia de la cintura (CC) y las pruebas físicas de salto horizontal (SH) y agilidad. Se calculó el Índice de Masa Corporal (IMC) y el estado de madurez. Resultados: No hubo diferencias en el peso y estatura entre ambos grupos en todos los rangos de edad (p>0,05). En la CC, los nadadores de ambos sexos mostraron valores inferiores en relación a los no-nadadores al menos desde los 6-7 años, 8-9 años y 10-11 años (p<0,05). En las pruebas físicas, no hubo diferencias en la agilidad entre ambos grupos (p>0,05), sin embargo, en el SH, los nadadores mostraron mejor despeño que sus similares no-nadadores (P<0,05), en los hombres a los 10-11 años y 12-13 años (p<0,05) y en las mujeres en todos los rangos de edad (p<0,05). Conclusión: Los jóvenes nadadores y no-nadadores presentaron un similar patrón de crecimiento físico en peso y estatura, excepto en la CC, donde los no-nadadores mostraron valores superiores. En las pruebas físicas, ambos grupos evidenciaron similares valores de agilidad en todos los rangos de edad y los nadadores mostraron mejores resultados en el SH que sus similares no nadadores. Estos resultados sugieren la práctica de la natación de tres veces por semana, lo que podría ayudar a mantener un adecuado perfil antropométrico y mejorar la fuerza de los miembros inferiores.(AU)


Introduction: The evaluation of physical growth and fit-ness is considered a beneficial task for health and sports per-formance.Objective: To compare the physical growth and fitness ofyoung swimmers and non-swimmers in a region of Peru Methodology: A descriptive (comparative) study was car-ried out in children and adolescents aged 6 to 13 years. Twostudy groups were formed. Group 1: Swimming practitioners(swimmers) and Group 2: Non-swimming practitioners (non-swimmers). Anthropometric measurements of weight, height,sitting height, waist circumference (WC) and the physicaltests of horizontal jump (HH) and agility were evaluated.Body Mass Index (BMI) and maturity status were calculated.Significant differences were determined by means of the “t”test for independent samples.Results: There were no differences in weight, sittingheight and height between both groups in all age ranges(p>0.05). In CC, swimmers of both sexes showed lower val-ues in relation to non-swimmers at least from 6-7 years, 8-9years and 10-11 years (p<0.05). In the physical tests, therewere no differences in agility between both groups (p>0.05),however, in the SH, swimmers showed better performancethan their similar non-swimmers (P<0.05), in males at 10-11years and 12-13 years (p<0.05) and in females in all ageranges (p<0.05).Conclusion: Young swimmers and non-swimmers pre-sented a similar pattern of physical growth in weight andheight, except in CC, where non-swimmers showed highervalues. In the physical tests, both groups evidenced similaragility values in all age ranges and swimmers showed betterresults in SH than their similar non-swimmers. These resultssuggest that the practice of swimming three times a week hasa positive role on the anthropometric profile, adipose andlower limb strength performance.(AU)


Subject(s)
Humans , Male , Female , Child , Adolescent , Physical Endurance , Physical Fitness , Swimming , Growth , Body Weight , Epidemiology, Descriptive , Peru
8.
Future Microbiol ; 19: 317-334, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38440893

ABSTRACT

Aims: This work describes the encapsulation of ceftazidime and tobramycin in zein nanoparticles (ZNPs) and the characterization of their antibacterial and antibiofilm activities against Gram-negative bacteria. Materials & methods: ZNPs were synthesized by nanoprecipitation. Cytotoxicity was assessed by MTT assay and antibacterial and antibiofilm assays were performed by broth microdilution and violet crystal techniques. Results: ZNPs containing ceftazidime (CAZ-ZNPs) and tobramycin (TOB-ZNPs) showed drug encapsulation and thermal stability. Encapsulation of the drugs reduced their cytotoxicity 9-25-fold. Antibacterial activity, inhibition and eradication of biofilm by CAZ-ZNPs and TOB-ZNPs were observed. There was potentiation when CAZ-ZNPs and TOB-ZNPs were combined. Conclusion: CAZ-ZNPs and TOB-ZNPs present ideal physical characteristics for in vivo studies of antibacterial and antibiofilm activities.


A nanotechnology product was developed to treat diseases caused by bacteria. This prototype showed the ideal characteristics and could be administered by ingestion through the mouth, aspiration through the nose or injection into the veins. The prototype did not harm or kill human cells. It killed the bacteria and prevented the formation of a type of protection against antibiotics that bacteria can produce, called a biofilm. Nanotechnology products are a promising alternative for the treatment of bacterial infections.


Subject(s)
Nanoparticles , Zein , Ceftazidime/pharmacology , Tobramycin/pharmacology , Zein/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Gram-Negative Bacteria , Microbial Sensitivity Tests
9.
Pharmaceuticals (Basel) ; 17(3)2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38543106

ABSTRACT

This study aimed to co-encapsulate ceftazidime and tobramycin in zein nanoparticles coated with chitosan and to characterize and evaluate the antibacterial and antibiofilm activity against antibiotic-resistant Pseudomonas aeruginosa and Klebsiella pneumoniae. Zein nanoparticles, synthesized using the nanoprecipitation method, were characterized by their particle size (Ø), polydispersity index (PDI), zeta potential (ζ), pH, and encapsulation efficiency (%EE). The chitosan coating provided stability, and physicochemical analyses revealed chemical interactions, efficient drug encapsulation, and thermal stability. The release kinetics demonstrated controlled release in simulated gastric and intestinal pH. The antibacterial activity, assessed by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), indicated effectiveness against both pathogens. Antibiofilm assays, conducted using the crystal violet method, demonstrated the inhibition and eradication of biofilms. The chitosan-coated zein nanoparticles with CAZ and/or TOB exhibited Ø (315-335 nm), PDI (<0.2), ζ (+40 to +50 mV), pH (5), and %EE (>55%). Notably, the co-encapsulation formulation (CAZ-TOB-ZNP-CH) showed enhanced antibacterial and antibiofilm activities compared to the individual formulations. These findings suggest that the developed nanoparticles present a promising alternative for treating respiratory and intestinal infections caused by antibiotic-resistant and biofilm-producing P. aeruginosa and K. pneumoniae.

10.
BMC Sports Sci Med Rehabil ; 16(1): 65, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38449019

ABSTRACT

BACKGROUND: Fat Free Mass (FFM) is an important and essential indicator in various sports populations, since greater muscle and bone mass generates greater strength, endurance and speed in athletes. OBJECTIVE: The purpose of the study was to validate Body Surface Area (BSA) as an anthropometric indicator to estimate FFM in young basketball players. METHODS: A descriptive cross-sectional study was carried out in 105 male basketball players of the Brazilian Basketball Confederation of Sao Paulo (Campinas), Brazil. The age range was 11 to 15 years. Weight and height were evaluated. BSA, body mass index (BMI) and maturity status (MS) were calculated. Total body scanning was performed by dual X-ray absorptiometry (DXA). The components were extracted: Fat mass (FM), Fat free mass (FFM), percentage of fat mass (%FM) and bone mass (BM). The data were analyzed using the correlation coefficient of concordance (CCC) in terms of precision and accuracy. RESULTS: Three regression equations were generated: equation 1 had age and body weight as predictors [FFM= -30.059+(2.926*age)+(0.625*Weight)] (R2 = 92%, precision = 0.96 and accuracy = 0.99), equation 2 used age and BSA [FFM=-45.719+(1.934*age)+(39.388*BSA)] (R2 = 94%, precision = 0.97 and accuracy = 0.99) and equation 3 was based on APHV and BSA [FFM=-15.284+(1.765*APHV)+(37.610*(BSA)] (R2 = 94%, precision = 0.96 and accuracy = 0.99). CONCLUSIONS: The results suggest the use of anthropometric equation using decimal age and BSA to estimate FFM in young basketball players. This new method developed can be used to design, evaluate and control training programs and monitor the weight status of athletes.

11.
Angew Chem Int Ed Engl ; 63(18): e202401281, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38462499

ABSTRACT

Carbon dioxide (CO2) is an abundant C1 feedstock with tremendous potential to produce versatile building blocks in synthetic applications. Given the adverse impact of CO2 on the atmosphere, it is of paramount importance to devise strategies for upcycling it into useful materials, such as polymers and fine chemicals. To activate such stable molecule, superbases offer viable modes of binding to CO2. In this study, a superbase cyclopropenimine derivative was found to exhibit exceptional proficiency in activating CO2 and mediating its polymerization at ambient temperature and pressure for the synthesis of polyurethanes. The versatility of this reaction can be extended to monofunctional amines and alcohols, yielding a variety of functional carbonates and carbamates.

12.
Appl Microbiol Biotechnol ; 108(1): 241, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38413482

ABSTRACT

The present work aimed to develop, characterize, and evaluate the antibacterial and antibiofilm activity of two nanoemulsions (NEs) containing 500 µg/mL of curcumin from Curcuma longa (CUR). These NEs, produced with heating, contain olive oil (5%) and the surfactants tween 80 (5%) and span 80 (2.5%), water q.s. 100 mL, and were stable for 120 days. NE-2-CUR presented Ø of 165.40 ± 2.56 nm, PDI of 0.254, ζ of - 33.20 ± 1.35 mV, pH of 6.49, and Entrapment Drug Efficiency (EE) of 99%. The NE-4-CUR showed a Ø of 105.70 ± 4.13 nm, PDI of 0.459, ζ of - 32.10 ± 1.45 mV, pH of 6.40 and EE of 99.29%. Structural characterization was performed using DRX and FTIR, thermal characterization using DSC and TG, and morphological characterization using SEM, suggesting that there is no significant change in the CUR present in the NEs and that they remain stable. The MIC was performed by the broth microdilution method for nine gram-positive and gram-negative bacteria, as well as Klebsiella pneumoniae clinical isolates resistant to antibiotics and biofilm and efflux pump producers. The NEs mostly showed a bacteriostatic profile. The MIC varied between 125 and 250 µg/mL. The most sensitive bacteria were Staphylococcus aureus and Enterococcus faecalis, for which NE-2-CUR showed a MIC of 125 µg/mL. The NEs and ceftazidime (CAZ) interaction was also evaluated against the K. pneumoniae resistant clinical isolates using the Checkerboard method. NE-2-CUR and NE-4-CUR showed a synergistic or additive profile; there was a reduction in CAZ MICs between 256 times (K26-A2) and 2 times (K29-A2). Furthermore, the NEs inhibited these isolates biofilms formation. The NEs showed a MBIC ranging from 15.625 to 250 µg/mL. Thus, the NEs showed physicochemical characteristics suitable for future clinical trials, enhancing the CAZ antibacterial and antibiofilm activity, thus becoming a promising strategy for the treatment of bacterial infections caused by multidrug-resistant K. pneumoniae. KEY POINTS: • The NEs showed physicochemical characteristics suitable for future clinical trials. • The NEs showed a synergistic/additive profile, when associated with ceftazidime. • The NEs inhibited biofilm formation of clinical isolates.


Subject(s)
Anti-Infective Agents , Curcumin , Anti-Bacterial Agents/pharmacology , Ceftazidime/pharmacology , Curcumin/pharmacology , Curcumin/chemistry , Olive Oil/pharmacology , Gram-Positive Bacteria , Gram-Negative Bacteria , Anti-Infective Agents/pharmacology , Klebsiella pneumoniae , Microbial Sensitivity Tests
13.
Nat Commun ; 15(1): 1202, 2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38378761

ABSTRACT

The Russian invasion of Ukraine on February 24, 2022, has had devastating effects on the Ukrainian population and the global economy, environment, and political order. However, little is known about the psychological states surrounding the outbreak of war, particularly the mental well-being of individuals outside Ukraine. Here, we present a longitudinal experience-sampling study of a convenience sample from 17 European countries (total participants = 1,341, total assessments = 44,894, countries with >100 participants = 5) that allows us to track well-being levels across countries during the weeks surrounding the outbreak of war. Our data show a significant decline in well-being on the day of the Russian invasion. Recovery over the following weeks was associated with an individual's personality but was not statistically significantly associated with their age, gender, subjective social status, and political orientation. In general, well-being was lower on days when the war was more salient on social media. Our results demonstrate the need to consider the psychological implications of the Russo-Ukrainian war next to its humanitarian, economic, and ecological consequences.


Subject(s)
Disease Outbreaks , Psychological Well-Being , Humans , Ukraine/epidemiology , Europe/epidemiology , Mental Health
14.
Disabil Rehabil Assist Technol ; : 1-7, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38164068

ABSTRACT

PURPOSE: Wheelchair users and people with disabilities have limited access to physical exercise due to various factors, including medical follow-up and training facilities. Although tele-exercise guided by experts has become a viable option, there is limited knowledge about the acute performance decrement (APD) resulting from remote training methods. The current cross-sectional study aimed to: (1) assess the APD of muscle resistance strength after three synchronous tele-exercise training methods in wheelchair users and (2) compare the training loads associated with each training method. MATERIALS AND METHODS: Eighteen male and female wheelchair users who participated in tele-exercise strength practices were recruited. The participants performed a maximum resistance strength test by synchronous tele-assessment (push-up test, PUT) at baseline and immediately after three training methods: high-intensity interval training (HIIT), moderate-intensity continuous training (MICT) and sprint interval training (SIT). The primary outcome was the APD, which was measured by the percentage decrease in the number of repetitions of the PUT immediately after the training methods. RESULTS: APD was observed for all three training methods, with no significant differences between them (-34.8%, -29.9% and -38.0% for MICT, SIT and HII, respectively), and presented a non-significant correlation with the training loads. HIIT had a significantly higher training load than MICT and SIT. CONCLUSIONS: APD occurred in all training sessions, but did not correlate with training load, indicating that it is not an appropriate metric for comparison. Findings provide insight into APD response and highlight the need to consider multiple metrics when comparing training protocols.


Synchronous moderate-intensity continuous training (MICT), sprint interval training (SIT) and high-intensity interval training tele-exercises provided similar acute performance decrement in wheelchair users and people with disabilities.High-intensity interval training showed a higher training load compared to MICT and SIT performed remotely.Acute performance decrement did not correlate with the training load.

15.
ACS Macro Lett ; : 181-188, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38252690

ABSTRACT

Organocatalyzed ring-opening polymerization is a powerful tool for the synthesis of a variety of functional, readily degradable polyesters and polycarbonates. We report the use of (thio)ureas in combination with cyclopropenimine bases as a unique catalyst for the polymerization of cyclic esters and carbonates with a large span of reactivities. Methodologies of exceptionally effective and selective cocatalyst combinations were devised to produce polyesters and polycarbonates with narrow dispersities (D = 1.01-1.10). Correlations of the pKa of the various ureas and cyclopropenimine bases revealed the critical importance of matching the pKa of the two cocatalysts to achieve the most efficient polymerization conditions. It was found that promoting strong H-bonding interactions with a noncompetitive organic solvent, such as CH2Cl2, enabled greatly increased polymerization rates. The stereoselective polymerization of rac-lactide afforded stereoblock poly(lactides) that crystallize as stereocomplexes, as confirmed by wide-angle X-ray scattering.

16.
Life Sci ; 341: 122462, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38281542

ABSTRACT

Colorectal cancer (CRC) remains a significant global health concern, necessitating continuous investigation into its etiology and potential risk factors. Recent research has shed light on the potential role of pKs-positive Escherichia coli (pKs + E. coli) and colibactin in the development and progression of CRC. Therefore, this review aimed to provide an updated analysis of the prevalence and implications of pKs + E. coli in colorectal cancer. We conducted a literature review search in major scientific databases to identify relevant studies exploring the association between pKs + E. coli and CRC. The search strategy included studies published up to the present date, and articles were carefully selected based on predefined inclusion criteria. Thus, the present study encompasses scientific evidence from clinical and epidemiological studies supporting the presence of pKs + E. coli in CRC patients, demonstrating a consistent and significant association in multiple studies. Furthermore, we highlighted the potential mechanisms by which colibactin may promote tumorigenesis and cancer progression within the colorectal mucosa, including the production of genotoxic virulence factors. Additionally, we explored current diagnostic methods for detecting pKs + E. coli in clinical settings, emphasizing the importance of accurate identification. Moreover, we discussed future strategies that could utilize the presence of this strain as a biomarker for CRC diagnosis and treatment. In conclusion, this review consolidated existing evidence on the prevalence and implications of pKs + E. coli in colorectal cancer. The findings underscore the importance of further research to elucidate the precise mechanisms linking this strain to CRC pathogenesis and to explore its potential as a therapeutic target or diagnostic marker. Ultimately, a better understanding of the role of pKs + E. coli in CRC may pave the way for innovative strategies in CRC management and patient care.


Subject(s)
Colorectal Neoplasms , Escherichia coli , Polyketides , Humans , Prevalence , Peptides , Colorectal Neoplasms/epidemiology
17.
J Pediatr (Rio J) ; 100(2): 189-195, 2024.
Article in English | MEDLINE | ID: mdl-37944907

ABSTRACT

OBJECTIVES: The aim was to estimate the pubertal growth height of children and adolescents living in a high-altitude region of Peru using the Preece-Baines model 1 (1 PB). METHODS: A cross-sectional study was conducted in schoolchildren from the department of Puno (Peru) between 3841 and 3874 masl. The age range was between 4 and 17 years. Standing height was evaluated. 1 PB was used to infer the mathematical and biological parameters of stature. RESULTS: Mathematical parameters estimated by the 1 PB model reflected small residual standard error (RSE) values in both sexes (0.25 in boys and 0.27 in girls). In boys, the age at which peak velocity was reached (APHV) was estimated at 13.21 ± 0.33years. While in girls it was 9.96 ± 0.26years (p < 0.05). In general, girls reached APHV (y) 3.25 years earlier than boys. On the other hand, the growth velocity of maximum height [APHV (cm/y)] of boys was higher (6.33 ± 6.06 cm/y) relative to girls (6.06 ± 0.32 cm/y). Estimated final adult height (EFAH) in boys was reached at 166.020 ± 0.99 cm and height at maximum growth velocity (HPHV) was 153.07 ± 0.67 cm, while in girls they were significantly lower (EFAH; 153.74 ± 0.44 cm and HPHV: 139.73 ± 0.84 cm). CONCLUSIONS: This study showed that girls living in Puno at a high altitude in Peru reached APHV 3 years earlier than boys and at the same time reflected slower PHV. These results suggest that pubertal growth at high altitudes is slower in both sexes and especially in girls. Thus, modeling physical growth may be an important step in understanding the onset of puberty at different latitudes.


Subject(s)
Altitude , Puberty , Male , Child , Female , Humans , Adolescent , Child, Preschool , Peru , Cross-Sectional Studies , Body Height , Growth
18.
J Equine Vet Sci ; 132: 104964, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37989472

ABSTRACT

Cribbing, a stereotypic oral behavior observed in horses, involves placing incisors on a fixed object, arching the neck, pulling against the object, and emitting an audible grunt. This behavior has been associated with gastrointestinal (GI) dysfunction and gastric ulceration. In this randomized crossover study, we investigated the impact of a GI support supplement (SPL) on the GI environment and physiology of four cribbing (CB) and four non-cribbing horses (NCB). Mature Quarter Horses, acclimated to individual stalls for 16 hours daily with paddock turnout in pairs for 8 hours per day, were randomly assigned to receive either the SPL or placebo for 21 days, followed by a 2-week washout period. Fecal and gastric samples were collected for pH determination and blood samples were analyzed for serum cortisol and gastrin levels. Endoscopic examinations assessed gastric ulcer severity, and cribbing frequency and bouts were recorded via video surveillance. Data were analyzed using a mixed-model ANOVA. Results showed no differences in fecal and gastric pH between cribbing statuses. However, an interaction between supplementation and cribbing status was observed for squamous mucosa ulcer scores (P=0.003). There were no differences in glandular mucosa ulcer scores, serum cortisol, serum gastrin, and crib-bite count between CB and NCB horses or between supplementation groups. Crib-bout duration did not differ with supplementation, but differences were found between periods (P<0.05) and hour ranges (P<0.001). Our findings suggest that the GI support supplement may not effectively address cribbing behavior or alter the GI environment in NCB or CB horses.


Subject(s)
Horse Diseases , Stomach Ulcer , Animals , Cross-Over Studies , Gastrins/blood , Horse Diseases/drug therapy , Horses , Hydrocortisone , Stereotyped Behavior/physiology , Stomach Ulcer/drug therapy , Stomach Ulcer/veterinary , Ulcer/veterinary
19.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1528270

ABSTRACT

Esta investigación tuvo como objetivo relatar la evolución del movimiento paralímpico y su vínculo con el escenario político nacional e internacional. Los Juegos Paralímpicos de Verano hicieron su debut en 1960, mientras que Chile participó por primera vez en 1992. Por otro lado, los Juegos Paralímpicos de Invierno comenzaron en 1976, y la primera participación chilena en este evento se produjo en 2002. Para el desarrollo del estudio se utilizó un análisis documental, donde se analizaron las convocatorias oficiales de las delegaciones chilenas, junto con las planillas de resultados generales obtenidos en los Juegos Paralímpicos, se extrajo de los documentos: el número de atletas participantes de ambos sexos y deportes, información que posteriormente fue agrupada en presencia o no de medallas y tipo de medalla obtenida y, a partir de aquello, se analizó por tipo de discapacidad y año de participación. A través de los años, Chile vivenció constantes procesos y cambios en los periodos de gestión, a esto se suma la promulgación de leyes, tanto nacionales como internacionales, junto con la constante ayuda recibida de distintas agrupaciones privadas y gubernamentales, resultando en un paulatino incremento de deportistas paralímpicos, situación que colaboró en gran medida con el desarrollo integral del movimiento paralímpico chileno hasta lo que es en la actualidad; este crecimiento facilitó resultados exitosos, como el obtenido en el año 2012 con la conquista de la primera medalla paralímpica de Chile, llegando a un total de siete medallas distribuidas en cuatro deportes en los Juegos Paralímpicos Tokio 2020, quedando situado en el ranking paralímpico en la cuadragésima quinta posición.


The aim of this paper was to describe the evolution of the Paralympic movement and its connection with the national and international political scenario. The Summer Paralympic Games made their debut in 1960, while Chile first participated in 1992. On the other hand, the Winter Paralympic Games began in 1976, and Chile's first participation in this event occurred in 2002. A documentary analysis was conducted for the study, in which the official documents of the Chilean delegations were analyzed, along with the overall results obtained in the Paralympic Games. The documents provided information on the number of participating athletes of both genders, results and sports. This information was later grouped based on the presence or absence of medals and the type of medal obtained. It was further analyzed by type of disability and year of participation. Over the years, Chile experienced constant processes and changes in management, in addition to the enactment of laws, both national and international. The constant support received from various private and governmental organizations contributed to the gradual increase in paralympic athletes, which greatly facilitated the overall development of the Chilean Paralympic movement to its current state. This growth led to successful outcomes, such as Chile's 1st Paralympic medal in 2012, and the country has now achieved a total of 7 medals in 4 disciplines in Paralympic Games Tokyo 2020, placing it in the 45th position in paralympic medal board.


O presente trabalho tem como objetivo relatar a evolução do movimento paralímpico e sua relação com o cenário político nacional e internacional. Os Jogos Paralímpicos de Verão fizeram sua estreia em 1960, enquanto o Chile participou pela primeira vez em 1992. Por outro lado, os Jogos Paralímpicos de Inverno começaram em 1976, e a primeira participação chilena neste evento ocorreu em 2002. O estudo foi realizado através de análise documental, de onde foram extraídas informações sobre as delegações chilenas, juntamente com as planilhas de resultados gerais obtidos dos Jogos Paralímpicos. As variáveis registradas foram número de atletas participantes de ambos os sexos, modalidades e esportes. As informações posteriormente foram agrupadas em quantidade de medalhas e tipo da medalha obtida, sendo analisadas por tipo de deficiência e ano de participação. Ao longo dos anos, o Chile experimentou constantes processos e mudanças nos períodos de gestão, como a promulgação de leis, tanto nacionais como internacionais, juntamente com a ajuda constante recebida de diferentes grupos privados e governamentais, resultando em aumento de atletas paralímpicos, situação que contribuiu com o desenvolvimento integral do movimento paralímpico chileno. Este crescimento facilitou resultados exitosos, como o obtido em 2012 com a conquista da primeira medalha paralímpica do Chile, alcançando hoje um total de 7 medalhas distribuídas em 4 disciplinas em Tóquio 2022, colocando-se na quadragésima quinta posição do quadro de medalhas.

20.
Rev. andal. med. deporte ; 16(3-4)dic.-2023. tab
Article in Spanish | IBECS | ID: ibc-ADZ-350

ABSTRACT

Objetivo: El propósito de este estudio fue describir el impacto del confinamiento causado por la pandemia de COVID-19 en la calidad de vida de para-atletas chilenos con lesiones cerebrales. Método: En este estudio participaron cuarenta futbolistas masculinos pertenecientes a equipos de clubes locales para-deportivos de Chile. Todos los participantes completaron el cuestionario de calidad de vida WHOQOL-BREF en dos momentos diferentes (antes y durante la pandemia). Resultados: Se encontró una reducción significativa en la percepción general de la calidad de vida entre los diferentes periodos. Además, los dominios físico, psicológico, social y ambiental presentaron puntuaciones más bajas durante el periodo de pandemia. Conclusiones Estos resultados sugieren que el impacto del confinamiento redujo la percepción de la calidad de vida en todos los dominios. Se necesitan estrategias diferenciadas con apoyo profesional multidisciplinario para hacer frente a las consecuencias psicosociales de la pandemia COVID-19 en para-atletas con lesiones cerebrales. (AU)


Subject(s)
Humans , Male , Pandemics , Coronavirus , Quality of Life , Sports , Athletes
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