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1.
J Sport Rehabil ; 31(8): 971-977, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35523422

RESUMEN

CONTEXT: Upper-extremity (UE) pain is a concern among softball adolescent athletes. However, research on preseason screening of demographic characteristics and clinical measures among those with and without UE pain among adolescent softball athletes is underreported. This study sought to present functional outcomes and clinical measures of shoulder and hip complex flexibility, range of motion (ROM), and strength in adolescent softball athletes with and without UE pain. DESIGN: Cross-sectional study. METHODS: Sixty-seven athletes were assessed at the start of the spring season. The Kerlan-Jobe Orthopedic Clinic Shoulder and Elbow Questionnaire was administered to determine UE function. UE measurements included shoulder ROM, flexibility, and strength; lower-extremity measurements included hip ROM and strength. These variables were reported for players with and without UE pain as mean and SD. Independent samples t tests were performed to analyze differences between the groups. RESULTS: Thirteen (19.4%) athletes reported UE pain during preseason screening. Mean Kerlan-Jobe Orthopedic Clinic Shoulder and Elbow Questionnaire score among athletes with UE pain was 58.0 (17.6) compared with 97.1 (6.9) for athletes reporting no UE pain (P < .001). Athletes with UE pain presented with significantly less dominant side external rotation ROM (UE pain: 106.5 [10.4], no UE pain: 114.6 [11.3]) and total ROM (UE pain: 163.7 [14.5], no UE Pain: 174.8 [14.3]). CONCLUSION: These findings inform clinicians on function and preseason clinical measures in adolescent softball athletes who present with or without UE pain. Athletes with UE pain demonstrated lower outcome scores indicating likely impact on overall UE function. These athletes also appeared to demonstrate UE ROM differences compared with athletes without UE pain. Further research is needed to investigate larger sample sizes and positional differences at baseline and throughout the season to determine if clinical measures used in the current study are risk factors for pain and injury.


Asunto(s)
Béisbol , Lesiones del Hombro , Adolescente , Humanos , Béisbol/lesiones , Estudios Transversales , Rango del Movimiento Articular , Hombro , Dolor
2.
J Chem Phys ; 153(8): 084901, 2020 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-32872893

RESUMEN

Colloids that interact via a short-range attraction serve as the primary building blocks for a broad range of self-assembled materials. However, one of the well-known drawbacks to this strategy is that these building blocks rapidly and readily condense into a metastable colloidal gel. Using computer simulations, we illustrate how the addition of a small fraction of purely repulsive self-propelled colloids, a technique referred to as active doping, can prevent the formation of this metastable gel state and drive the system toward its thermodynamically favored crystalline target structure. The simplicity and robust nature of this strategy offers a systematic and generic pathway to improving the self-assembly of a large number of complex colloidal structures. We discuss in detail the process by which this feat is accomplished and provide quantitative metrics for exploiting it to modulate the self-assembly. We provide evidence for the generic nature of this approach by demonstrating that it remains robust under a number of different anisotropic short-ranged pair interactions in both two and three dimensions. In addition, we report on a novel microphase in mixtures of passive and active colloids. For a broad range of self-propelling velocities, it is possible to stabilize a suspension of fairly monodisperse finite-size crystallites. Surprisingly, this microphase is also insensitive to the underlying pair interaction between building blocks. The active stabilization of these moderately sized monodisperse clusters is quite remarkable and should be of great utility in the design of hierarchical self-assembly strategies. This work further bolsters the notion that active forces can play a pivotal role in directing colloidal self-assembly.

3.
Histochem Cell Biol ; 152(2): 155-166, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31111198

RESUMEN

Trace amine-associated receptors are G protein-coupled receptors of which TAAR1 is the most well-studied. Recently, Vattai et al. (J Cancer Res Clin Oncol 143:1637-1647 https://doi.org/10.1007/s00432-017-2420-8 , 2017) reported that expression of TAAR1 may be a marker of breast cancer (BC) survival, with a positive correlation also suggested between TAAR1 expression and HER2 positivity. Neither a role for TAAR1 in breast tissue, nor in cancer, had previously been suspected. We, therefore, sought to provide independent validation and to further examine these putative relationships. First, a bioinformatic analysis on 58 total samples including normal breast tissue, BC-related cell lines, and tumour samples representing different BC sub-types found no clear correlation between TAAR1 mRNA levels and any BC subtype, including HER2 + . We next confirmed the bioinformatics data correlated to protein expression using a well validated anti-human TAAR1 antibody. TAAR1 mRNA levels correlated with the relative intensity of immunofluorescence staining in six BC cell lines (MCF-7, T47D, MDA-MB-231, SKBR3, MDA-MB-468, BT-474), but not in the MCF-10A immortalized mammary gland line, which had high mRNA but low protein levels. As expected, TAAR1 protein was intracellular in all cell lines. Surprisingly MCF-7, SKBR3, and MDA-MB-468 showed pronounced nuclear localization. The relative protein expression in MCF-7, MDA-MB-231, and MCF-10A lines was further confirmed by semi-quantitative flow cytometry. Finally, we demonstrate that the commercially available anti-TAAR1 antibody has poor selectivity, which likely explains the lack of correlation with the previous study. Therefore, while we clearly demonstrate variable expression and sub-cellular localization of TAAR1 across BC cell lines, we find no evidence for association with BC subtype.


Asunto(s)
Neoplasias de la Mama/genética , Receptores Acoplados a Proteínas G/análisis , Receptores Acoplados a Proteínas G/genética , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/metabolismo , Línea Celular , Biología Computacional , Femenino , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Humanos , ARN Mensajero/análisis , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
4.
J Cutan Pathol ; 45(6): 443-452, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29484694

RESUMEN

Biphasic lesions comprised of melanocytic and epithelial components are rare entities believed to arise either as a collision of 2 histologically distinct lesions in the same anatomic location or as a singular progenitor tumor differentiating along 2 differing lineages. Regardless of mechanism of origin, these tumors present unique challenges in pathologic interpretation and in determining appropriate measurements, which assigns subsequent prognosis to the patient. We present 4 tumors of melanoma co-existing with basal cell carcinoma (BCC) and discuss relevant literature regarding these biphasic entities. Patients consisted of 3 males and 1 female, ranging in age from 62 to 93, with lesions located on the shoulder, frontal scalp, forearm and nose. Three of 4 lesions showed melanoma cells limited to BCC tumor lobules, without evidence of direct dermal invasion by melanoma cells, raising the question of whether or not these tumors should be classified as in situ or invasive melanoma. These cases highlight the complexity that such lesions pose to dermatopathologists, in terms of their uncertain origin and variable microscopic appearance. In the absence of data regarding outcomes for these tumors (given their rarity), it is important to utilize a case-by-case approach, with careful clinical correlation and appropriate use of ancillary techniques.


Asunto(s)
Carcinoma Basocelular/patología , Melanoma/patología , Neoplasias Primarias Múltiples/patología , Neoplasias Cutáneas/patología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
5.
Pediatr Exerc Sci ; 30(1): 150-156, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29376457

RESUMEN

BACKGROUND: Mobile Internet-connected electronic devices provide access to activities that have traditionally been associated with sedentary behavior. Because they are portable, these devices can be utilized in any environment. Therefore, providing children with access to these devices in environments that typically promote physical activity may result in a reduction in physical activity behavior. PURPOSE: To assess children's physical and sedentary (ie, sitting) activity with and without the presence of a mobile Internet-connected tablet computer. METHODS: A total of 20 children [6.7 (1.9) y old] participated in 2 simulated recess conditions in a gymnasium on separate days. During each condition, children had free-choice access physical activity options and a table of sedentary activities for 40 minutes. During 1 session, the iPad was present, and in the other session, it was not. Physical activity was monitored via an accelerometer, and sedentary time was monitored via a stopwatch. RESULTS: Children significantly (P ≤ .03) reduced average physical activity intensity and increased their sedentary behavior with the iPad present [4.4 (4.0) metabolic equivalents/min and 20.9 (12.4) min sitting] versus the condition without the iPad present [5.3 (4.0) metabolic equivalents/min and 13.6 (13.2) min sitting]. CONCLUSION: Introducing an mobile Internet-connected tablet computer into a gymnasium reduced children's physical activity intensity by 17% and increased sedentary behavior by 54%.


Asunto(s)
Conducta Infantil , Computadoras de Mano , Ejercicio Físico , Conducta Sedentaria , Acelerometría , Niño , Femenino , Humanos , Internet , Masculino
6.
J Strength Cond Res ; 32(4): 1166-1173, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28445228

RESUMEN

Johnson, CD, Whitehead, PN, Pletcher, ER, Faherty, MS, Lovalekar, MT, Eagle, SR, and Keenan, KA. The relationship of core strength and activation and performance on three functional movement screens. J Strength Cond Res 32(4): 1166-1173, 2018-Current measures of core stability used by clinicians and researchers suffer from several shortcomings. Three functional movement screens appear, at face-value, to be dependent on the ability to activate and control core musculature. These 3 screens may present a viable alternative to current measures of core stability. Thirty-nine subjects completed a deep squat, trunk stability push-up, and rotary stability screen. Scores on the 3 screens were summed to calculate a composite score (COMP). During the screens, muscle activity was collected to determine the length of time that the bilateral erector spinae, rectus abdominis, external oblique, and gluteus medius muscles were active. Strength was assessed for core muscles (trunk flexion and extension, trunk rotation, and hip abduction and adduction) and accessory muscles (knee flexion and extension and pectoralis major). Two ordinal logistic regression equations were calculated with COMP as the outcome variable, and: (a) core strength and accessory strength, (b) only core strength. The first model was significant in predicting COMP (p = 0.004) (Pearson's Chi-Square = 149.132, p = 0.435; Nagelkerke's R-Squared = 0.369). The second model was significant in predicting COMP (p = 0.001) (Pearson's Chi-Square = 148.837, p = 0.488; Nagelkerke's R-Squared = 0.362). The core muscles were found to be active for most screens, with percentages of "time active" for each muscle ranging from 54-86%. In conclusion, performance on the 3 screens is predicted by core strength, even when accounting for "accessory" strength variables. Furthermore, it seems the screens elicit wide-ranging activation of core muscles. Although more investigation is needed, these screens, collectively, seem to be a good assessment of core strength.


Asunto(s)
Prueba de Esfuerzo/métodos , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Equilibrio Postural/fisiología , Adolescente , Adulto , Estudios Transversales , Electromiografía/métodos , Ejercicio Físico/fisiología , Femenino , Humanos , Masculino , Movimiento/fisiología , Contracción Muscular/fisiología , Rango del Movimiento Articular , Torso/fisiología , Adulto Joven
7.
J Pediatr ; 170: 206-10, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26725460

RESUMEN

OBJECTIVES: To assess the amount, intensity, enjoyment, and preference of children's physical activity in a controlled gymnasium setting under 3 experimental, social conditions: alone, with a parent watching, and with a parent participating. STUDY DESIGN: Children (n = 10 girls, 10 boys), 3-6 years old, along with 1 parent (n = 17 mothers, 3 fathers) per child participated in each social condition on separate days for 30 minutes in which they could choose from a variety of physical and/or sedentary activities. RESULTS: A greater number of accelerometer counts (P ≤ .02) were accumulated during the parent participating (109,523 ± 32,155 counts) condition than the alone (67,938 ± 37,857 counts) and parent watching (85,624 ± 44,985 counts) conditions. Counts during parent watching were also greater (P = .01) than alone. More time (P ≤ .008) was allocated to sedentary activities during the alone (16.2 ± 9.6 minutes) condition than parent watching (9.6 ± 9.3 minutes) and parent participating (3.8 ± 5.1 minutes). Children liked (P ≤ .02) the parent participating (9.9 ± 0.45 cm) condition more than alone (8.0 ± 2.72 cm) and parent watching (8.7 ± 1.52 cm). A greater (P < .001) proportion of children identified the parent participating (80%) as their preferred condition over either the parent watching (10%) or alone (10%) conditions. CONCLUSIONS: Parental participation during physical activity (or at minimum direct supervision) may be an important component in the development of physical activity environments intended to maximize physical activity behavior in children.


Asunto(s)
Ejercicio Físico , Conductas Relacionadas con la Salud , Relaciones Padres-Hijo , Padres , Acelerometría/instrumentación , Adulto , Niño , Preescolar , Metabolismo Energético , Femenino , Humanos , Masculino
9.
Mol Pharm ; 11(11): 4249-57, 2014 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-25294389

RESUMEN

Bevacizumab and cetuximab are approved for the treatment of cancer. However, in advanced colorectal cancer, addition of cetuximab to chemotherapy with bevacizumab did not improve survival. The reason for the lack of activity remains unclear. The aim of this study was to determine the effect of cetuximab on VEGF expression and targeting of bevacizumab to the tumor. Mice with subcutaneous SUM149 or WiDr xenografts were treated with cetuximab, bevacizumab, or a combination of the two. Before the start of cetuximab treatment and after 7 and 21 days of treatment, the uptake of radiolabeled bevacizumab in the tumor was measured by immunoSPECT/CT. Tumor growth of SUM149 xenografts was significantly inhibited by cetuximab, bevacizumab, or their combination, whereas growth of WiDr xenografts was not affected. Cetuximab caused a significant reduction of bevacizumab uptake in SUM149 xenografts, whereas tumor-to-blood ratios in mice with WiDr xenografts did not change. Biodistribution studies with an irrelevant antibody in the SUM149 model also showed significantly reduced tumor-to-blood ratios. Cetuximab treatment did not decrease VEGF expression. Without decreasing VEGF levels, cetuximab reduces tumor targeting of bevacizumab. This could, at least partly, explain why the combination of bevacizumab and cetuximab does not result in improved therapeutic efficacy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Receptores ErbB/metabolismo , Terapia Molecular Dirigida , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Anticuerpos Monoclonales Humanizados/administración & dosificación , Bevacizumab , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Cetuximab , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Técnicas para Inmunoenzimas , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Imagen Multimodal , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
10.
J Chem Phys ; 141(19): 194901, 2014 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-25416906

RESUMEN

Using numerical simulations, we study how a solution of small active disks, acting as depletants, induces effective interactions on large passive colloids. Specifically, we analyze how the range, strength, and sign of these interactions are crucially dependent on the shape of the colloids. Our findings indicate that while colloidal rods experience a long-ranged predominantly attractive interaction, colloidal disks feel a repulsive force that is short-ranged in nature and grows in strength with the size ratio between the colloids and active depletants. For colloidal rods, simple scaling arguments are proposed to characterize the strength of these induced interactions.

11.
Parasit Vectors ; 17(1): 313, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39030610

RESUMEN

BACKGROUND: Canine acaricides with rapid onset and sustained activity can reduce pathogen transmission risk and enhance pet owner experience. This randomized, complete block design, investigator-masked study compared the speed of kill of Amblyomma americanum provided by three monthly-use isoxazoline-containing products. METHODS: Eight randomized beagles per group were treated (day 0), per label, with sarolaner (combined with moxidectin and pyrantel, Simparica Trio™), afoxolaner (NexGard™), or lotilaner (Credelio™), or remained untreated. Infestations with 50 adult A. americanum were conducted on days - 7, - 2, 21, and 28, and tick counts were performed on day - 5 (for blocking), and at 4, 8, 12, 24, 48, and 72 h following treatment and subsequent infestations. Efficacy calculations were based on geometric mean live tick counts. A linear mixed model was used for between-group comparisons. RESULTS: On day 0, only lotilaner significantly reduced an A. americanum infestation by 12 h (43.3%; P = 0.002). Efficacy of lotilaner and afoxolaner at 24 h post-treatment was 95.3% and 97.6%, respectively, both significantly different from sarolaner (74%) (P = 0.002, P < 0.001, respectively). On day 21, at 12 h postinfestation, lotilaner efficacy (59.6%) was significantly different from sarolaner (0.0%) (P < 0.001) and afoxolaner (6.3%) (P < 0.001). At 24 h, lotilaner efficacy (97.4%) was significantly different (P < 0.001) from sarolaner and afoxolaner (13.6% and 14.9%, respectively). On day 28, at 12 h postinfestation, lotilaner efficacy (47.8%) was significantly different from sarolaner (17.1%) (P = 0.020) and afoxolaner (9.0%) (P = 0.006). At 24 h, lotilaner efficacy (92.3%) was significantly different from sarolaner 4.9% (P < 0.001) and afoxolaner (0.0%) (P < 0.001). Speed of kill for sarolaner and afoxolaner, but not lotilaner, significantly declined over the study period. Following reinfestation on day 28, neither sarolaner nor afoxolaner reached 90% efficacy by 48 h. By 72 h, sarolaner efficacy was 97.4% and afoxolaner efficacy was 86.3%. Only lotilaner achieved ≥ 90% efficacy by 24 h post-treatment and 24 h postinfestation on days 21 and 28. Time to ≥ 90% efficacy following new infestations consistently occurred 24-48 h earlier for lotilaner compared with sarolaner or afoxolaner. CONCLUSIONS: Credelio (lotilaner) has a more rapid onset of acaricidal activity against A. americanum than Simparica Trio (sarolaner-moxidectin-pyrantel) and NexGard (afoxolaner). Only lotilaner's speed of tick kill is sustained throughout the dosing period.


Asunto(s)
Acaricidas , Amblyomma , Azetidinas , Enfermedades de los Perros , Isoxazoles , Infestaciones por Garrapatas , Animales , Perros , Infestaciones por Garrapatas/veterinaria , Infestaciones por Garrapatas/tratamiento farmacológico , Infestaciones por Garrapatas/prevención & control , Acaricidas/administración & dosificación , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/parasitología , Isoxazoles/administración & dosificación , Isoxazoles/uso terapéutico , Amblyomma/efectos de los fármacos , Azetidinas/administración & dosificación , Azetidinas/uso terapéutico , Femenino , Compuestos de Espiro/administración & dosificación , Compuestos de Espiro/uso terapéutico , Masculino , Factores de Tiempo , Naftalenos/administración & dosificación , Naftalenos/uso terapéutico , Resultado del Tratamiento , Oxazoles , Tiofenos
12.
J Strength Cond Res ; 27(12): 3419-25, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24270457

RESUMEN

The purpose of this study was to investigate the effects of an 8-week aquatic treadmill running (ATM) Tabata interval-training program on various performance variables including body fat percentage, force production, flexibility, and anaerobic power. Totally, 25 participants (17 males and 8 females) were randomized into either a control group (CON), which only completed Pre- and Posttesting, or exercise group (EX), which took part in the 8-week ATM Tabata interval-training program. Pre- and Posttesting consisted of the following measurements: body fat percentage, flexibility, force production, and anaerobic power. The Tabata interval-training program consisted of sprinting on an ATM at 7.5 miles⋅h and with the front jets turned on at 80, 85, 90, and 95% progressively increasing throughout the 8 weeks. A 2-way repeated measures analysis of variance revealed a significant effect of time (F = 236.13; p < 0.001) and group by time interaction (F = 1.95; p = 0.02). Paired-samples t-test revealed a significant difference in the CON group from Pre- to Posttesting for mean power from the Wingate test (t = -2.20; p = 0.05) and a significant difference in the EX group for right leg goniometry (t = -2.34; p = 0.04) and mean power from the Wingate test (t = -2.81; p = 0.02). These results are favorable because it demonstrates that participants who engage in an ATM Tabata interval-training program can elicit a strong enough stimulus to improve flexibility and anaerobic power in terms of mean power while decreasing musculoskeletal impact placed on the ligaments, joints, and tendons.


Asunto(s)
Rendimiento Atlético/fisiología , Carrera/fisiología , Agua , Adiposidad , Umbral Anaerobio , Análisis de Varianza , Artrometría Articular , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Rango del Movimiento Articular , Adulto Joven
13.
PLoS One ; 18(4): e0284883, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37083701

RESUMEN

A lateral jump assessment may provide unique benefits in sports such as basketball that require multidirectional performance optimization. This study aimed to examine selected force-plate derived metrics as predictors of lateral jump task distance in men's basketball players. Twenty-two NCAA Division-I men's basketball players (19.4 ± 1.3 years, 95.0 ± 12.5 kg, 196.5 ± 8.1 cm) each performed six single leg lateral jumps while standing on a force plate (1200 Hz, Kistler Instrument Corp). The lateral jump task involved the subject beginning by standing on the force plate and jumping sideways off one foot and then landing on the floor with the opposite foot. Three-dimensional ground reaction force curves were used to identify the eccentric and concentric phases of the jump and variables were computed each from the lateral (y), vertical (z), and resultant (r) force traces. Peak ground reaction force (pGRF), ground reaction force angle (θr), eccentric braking rate of force development (ECC-RFD), average concentric force (CON-AVG), total jump duration, eccentric phase duration, and eccentric to total time ratio were evaluated for predictive ability. Three regression models were able to significantly (p<0.05) predict jump distance: (1) pGRFy, pGRFz, and θr (p<0.001, R2 = 0.273), (2) Relative pGRFy, Relative pGRFz, and θr ((p<0.001, R2 = 0.214), and (3) Relative CON-AVGy and Relative pGRFr (p<0.001, R2 = 0.552). While several force plate-derived metrics were identified as significant predictors, a model with Relative CON-AVGy and Relative pGRFr explained a greater variability in performance (R2 = 0.55) compared to the other variables which were low, yet also significant. These results suggest that lateral ground reaction forces can be used to evaluate lateral jump performance with the use of three-dimensional force plates. The identified predictors can be used as a starting point for performance monitoring, as basketball training interventions can be directed at specific improvements in the identified metrics.


Asunto(s)
Rendimiento Atlético , Baloncesto , Masculino , Humanos , Fenómenos Biomecánicos , Extremidad Inferior
14.
Sci Total Environ ; 834: 155332, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35460788

RESUMEN

Selenium (Se) is a toxic contaminant with multiple anthropogenic sources, including 79Se from nuclear fission. Se mobility in the geosphere is generally governed by its oxidation state, therefore understanding Se speciation under variable redox conditions is important for the safe management of Se contaminated sites. Here, we investigate Se behavior in sediment groundwater column systems. Experiments were conducted with environmentally relevant Se concentrations, using a range of groundwater compositions, and the impact of electron-donor (i.e., biostimulation) and groundwater sulfate addition was examined over a period of 170 days. X-Ray Absorption Spectroscopy and standard geochemical techniques were used to track changes in sediment associated Se concentration and speciation. Electron-donor amended systems with and without added sulfate retained up to 90% of added Se(VI)(aq), with sediment associated Se speciation dominated by trigonal Se(0) and possibly trace Se(-II); no Se colloid formation was observed. The remobilization potential of the sediment associated Se species was then tested in reoxidation and seawater intrusion perturbation experiments. In all treatments, sediment associated Se (i.e., trigonal Se(0)) was largely resistant to remobilization over the timescale of the experiments (170 days). However, in the perturbation experiments, less Se was remobilized from sulfidic sediments, suggesting that previous sulfate-reducing conditions may buffer Se against remobilization and migration.


Asunto(s)
Agua Subterránea , Selenio , Contaminantes Radiactivos del Agua , Sedimentos Geológicos/química , Agua Subterránea/química , Oxidación-Reducción , Selenio/química , Sulfatos , Contaminantes Radiactivos del Agua/química
15.
Clin Biomech (Bristol, Avon) ; 91: 105533, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34847471

RESUMEN

BACKGROUND: Injury to the anterior cruciate ligament (ACL) can lead to long-lasting biomechanical alterations that put individuals at risk of a second ACL injury. Examining the total support moment may reveal between- and within-limb compensatory strategies. METHODS: Twenty-six participants who were cleared to return to sport following ACL reconstruction were recruited. Each participant completed the single-leg and double-leg stop jump tasks. These tasks were analyzed using force plates and a 3D motion analysis system. The total support moment was calculated by summing the internal moments of the hip, knee and ankle at peak vertical ground reaction force. FINDINGS: Internal knee extensor moment was lower in the involved limb compared to the uninvolved for both tasks (17.6%, P = 0.022; 18.4%, P = 0.008). No significant between-limb differences were found for the total support moment. The involved limb exhibited an 18.2% decrease in knee joint contribution (P = 0.01) and a 21.6% increase in ankle joint contribution (P = 0.016) to the total support moment compared to the uninvolved limb in the single-leg stop jump task. INTERPRETATION: Compensation for the involved knee is likely due to altered biomechanics that redistributes load to the uninvolved knee or to adjacent joints of the same limb. A partial shift in joint contribution from the knee to the ankle during the single-leg stop jump task demonstrates a tendency to decrease load to the knee. Further studies are needed to investigate how these adaptations impact the prevalence of subsequent injury and poor joint health.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Lesiones del Ligamento Cruzado Anterior/cirugía , Fenómenos Biomecánicos , Humanos , Articulación de la Rodilla/cirugía , Pierna , Extremidad Inferior/cirugía
16.
Int J Sports Phys Ther ; 17(7): 1330-1339, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36518832

RESUMEN

Background: Anterior cruciate ligament (ACL) injury is extremely common among athletes. Rate of second ACL injury due to surgical graft rupture or contralateral limb ACL injury is approximately 15-32%. Psychological readiness to return to sport (RTS) may be an important predictor of successful RTS outcomes. Psychological readiness can be quantified using the ACL Return to Sport after Injury (ACL-RSI) questionnaire, with higher scores demonstrating greater psychological readiness. Purpose: The purpose of this study was to investigate differences in functional performance and psychological readiness to return to sport among athletes who have undergone primary ACL reconstruction (ACLR). Study Design: Descriptive cohort study. Methods: Eighteen athletes who had undergone primary ACLR were tested at time of RTS clearance. The cohort was divided into two groups, high score (HS) and low score (LS), based on median ACL-RSI score, and performance on static and dynamic postural stability testing, lower extremity isokinetic and isometric strength testing, and single leg hop testing was compared between the groups using an independent samples t-test. Results: The median ACL-RSI score was 74.17. The average ACL-RSI score was 83.1±6.2 for the HS group and 61.8±8.0 for the LS group. High scorers on the ACL-RSI performed significantly better on isometric knee flexion as measured via handheld dynamometry (22.61% ±6.01 vs. 12.12% ±4.88, p=0.001) than the low score group. Conclusion: The findings suggest that increased knee flexion strength may be important for psychological readiness to RTS after primary ACLR. Further research is indicated to explore this relationship, however, a continued emphasis on improving hamstring strength may be appropriate during rehabilitation following ACLR to positively impact psychological readiness for RTS. Level of Evidence: III.

17.
Int J Sports Phys Ther ; 17(4): 556-565, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35693866

RESUMEN

Purpose: There is a high rate of second anterior cruciate ligament (ACL) injury (ipsilateral graft or contralateral ACL) upon return-to-sport (RTS) following ACL reconstruction (ACLR). While a significant amount of epidemiological data exists demonstrating sex differences as risk factors for primary ACL injury, less is known about sex differences as potential risk factors for second ACL injury. The purpose of this study is to determine if there are sex-specific differences in potential risk factors for second ACL injury at the time of clearance for RTS. Methods: Ten male and eight female athletes (age: 20.8 years ±6.3, height: 173.2 cm ±10.1, mass: 76.6 kg ±18.3) participated in the study following ACLR at time of RTS (mean 10.2 months). Performance in lower extremity isokinetic and isometric strength testing, static and dynamic postural stability testing, and a single leg stop-jump task was compared between the sexes. Results: Normalized for body weight, males had significantly greater isokinetic knee flexion (141±14.1 Nm/kg vs. 78±27.4 Nm/kg, p=0.001) and extension strength (216±45.5 Nm/kg vs. 159±53.9 Nm/kg, p=0.013) as well as isometric flexion (21.1±6.87% body weight vs. 12.5±5.57% body weight, p=0.013) and extension (41.1±7.34% body weight vs. 27.3±11.0% body weight, p=0.016) strength compared to females. In the single-leg stop jump task, males had a greater maximum vertical ground reaction force during landing (332±85.5% vs. 259±27.4% body weight, p=0.027) compared to females. Conclusions: Based on these results, there are significant differences between sexes following ACLR at the time of RTS. Lower knee flexion and extension strength may be a potential risk factor for second ACL injury among females. Alternatively, the increased maximum vertical force observed in males may be a potential risk factor of second ACL injury in males. Although these results should be interpreted with some caution, they support that rehabilitation programs in the post-ACLR population should be individualized based on the sex of the individual. Level of Evidence: Level 3.

18.
Int J Sports Phys Ther ; 16(1): 64-71, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33604136

RESUMEN

BACKGROUND: Lower extremity (LE) injuries are common across many sports. Both core strength (including hip strength) deficits and poor postural stability have been linked to lower extremity (LE) injury. The relationship between these two characteristics is unknown. PURPOSE: To explore the relationships between hip strength, static postural stability, and dynamic postural stability. STUDY DESIGN: Descriptive Cross-Sectional Study. METHODS: 162 Division I student-athletes (111 males and 51 females) participated in this study. Isometric hip strength was measured using a hand-held dynamometer and both single-leg static (eyes open EO and eyes closed EC) and dynamic postural stability were assessed with a force plate. Pairwise correlations were calculated to examine the relationship between the hip strength variables and the postural stability scores for all subjects and separately for males and females. RESULTS: There were no significant correlations between hip strength and dynamic postural stability for any of the pairwise correlations. Significant, albeit minimal, correlations between EO and EC static postural stability and each of the hip strength variables for all subjects and male subjects (correlation coefficients ranged from -0.19 to -0.34). However, there were only two significant correlations between hip strength and EC static postural stability (hip internal/external rotation) and one for hip strength and EO postural stability (hip internal rotation) found for female subjects (correlation coefficients ranged from -0.28 to -0.31). CONCLUSION: There was no relationship between isometric hip strength and dynamic postural stability; whereas, there were some relationships between the strength measures and static postural stability. These significant, but minimal correlations were observed in more of the comparisons within the male cohort potentially demonstrating a sex difference. LEVEL OF EVIDENCE: 3b.

19.
Behav Brain Res ; 413: 113466, 2021 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-34271036

RESUMEN

Autism spectrum disorder (ASD) is a pervasive neurodevelopmental disorder characterized by impairments in social interaction, cognition, and communication, as well as the presence of repetitive or stereotyped behaviors and interests. ASD is most often studied as a neurodevelopmental disease, but it is a lifelong disorder. Adults with ASD experience more stressful life events and greater perceived stress, and frequently have comorbid mood disorders such as anxiety and depression. It remains unclear whether adult exposure to chronic stress can exacerbate the behavioral and neurodevelopmental phenotypes associated with ASD. To address this issue, we first investigated whether adult male and female Engrailed-2 deficient (En2-KO, En2-/-) mice, which display behavioral disturbances in avoidance tasks and dysregulated monoaminergic neurotransmitter levels, also display impairments in instrumental behaviors associated with motivation, such as the progressive ratio task. We then exposed adult En2-KO mice to chronic environmental stress (CSDS, chronic social defeat stress), to determine if stress exacerbated the behavioral and neuroanatomical effects of En2 deletion. En2-/- mice showed impaired instrumental acquisition and significantly lower breakpoints in a progressive ratio test, demonstrating En2 deficiency decreases motivation to exert effort for reward. Furthermore, adult CSDS exposure increased avoidance behaviors in En2-KO mice. Interestingly, adult CSDS exposure also exacerbated the deleterious effects of En2 deficiency on forebrain-projecting monoaminergic fibers. Our findings thus suggest that adult exposure to stress may exacerbate behavioral and neuroanatomical phenotypes associated with developmental effects of genetic En2 deficiency.


Asunto(s)
Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/fisiopatología , Reacción de Prevención/fisiología , Conducta Animal/fisiología , Interacción Gen-Ambiente , Motivación/fisiología , Proteínas del Tejido Nervioso/deficiencia , Estrés Psicológico/fisiopatología , Animales , Modelos Animales de Enfermedad , Femenino , Proteínas de Homeodominio , Masculino , Ratones
20.
Int J Cardiol ; 299: 56-62, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31229262

RESUMEN

BACKGROUND: Coronary artery calcium (CAC) scanning has evolved into an important subclinical prediction method for cardiovascular diseases in asymptomatic subjects. However, the prognostic implication of CAC scanning in symptomatic individuals is less clear. OBJECTIVES: To assess the prognostic utility of CAC in predicting risk of major adverse cardiac events (MACE) in stable patients with suspected CAD. METHODS: We did a systematic electronic literature search for studies presenting original data in CAC score, and reporting cardiovascular events in stable, symptomatic patients as primary outcome. Primary outcome of the meta-analysis was the occurrence of MACE, a composite of late coronary revascularization, hospitalization for unstable angina or heart failure, nonfatal myocardial infarction, and cardiac death or all-cause mortality. Using random effects models, we pooled relative risk ratios of CAC for MACE, and adjusted hazard ratios (HR) of the associations between different CAC strata (CAC 0-100,100-400, and ≥ 400, versus CAC = 0) and incident MACE. RESULTS: We included 19 observational studies (n = 34,041). In total, 1601 events were analyzed, of which 158 in patients with CAC = 0. The pooled relative risk ratio was 5.71 (95%-CI: 3.98;8.19) for subjects with CAC > 0. The pooled estimate of adjusted HRs demonstrated increasing, positive associations, with the strongest association for CAC > 400 (HR: 4.88; 95%-CI: 2.44;9.27). CONCLUSIONS: This meta-analysis demonstrated that increased levels of CAC are strongly and independently associated with increased risk for MACE in stable, symptomatic patients with suspected CAD, showing increasing risk with greater CAC scores. Application of CAC scanning as a prediction method could be useful for a considerable number of such patients.


Asunto(s)
Calcio/sangre , Vasos Coronarios/diagnóstico por imagen , Estudios Observacionales como Asunto/métodos , Calcificación Vascular/sangre , Calcificación Vascular/diagnóstico por imagen , Angiografía Coronaria/métodos , Humanos , Pronóstico , Tomografía Computarizada por Rayos X/métodos
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