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Histopathology ; 75(6): 799-812, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30861172


AIMS: The clinical implications of the programmed cell death 1 (PD1)/programmed cell death-ligand 1 (PD-L1) axis in patients with post-transplant lymphoproliferative disorders are largely unknown, and its association with Epstein-Barr virus (EBV) status and PD-L1 copy number alterations (CNAs) has not been thoroughly studied. METHODS AND RESULTS: PD1/PD-L1 expression was studied in 50 adult post-transplant lymphoproliferative disorders, and the correlations with PD-L1 CNAs, EBV, clinicopathological features and outcome were evaluated. Thirty-seven (74%) cases were classified as diffuse large B-cell lymphoma (DLBCL), nine (18%) cases were classified as polymorphic, and four (8%) cases were classified as classic Hodgkin lymphoma. Thirty-four cases were EBV-positive, with 29 of 34 (85%) having latency II or III, and 15 of 34 (44%) having viral replication. PD-L1 expression in tumour cells and tumour-associated macrophages was observed in 30 (60%) and 37 (74%) cases, respectively. PD1 positivity was seen in 16 (32%) cases. PD-L1 expression was associated with EBV with latency II or III (P = 0.001) and organ rejection (P = 0.04), and, in DLBCL, with non-germinal centre type DLBCL (P < 0.001). Cases with PD-L1-positive tumour cells showed a higher number of PD-L1 CNAs than PD-L1-negative cases (P = 0.001). Patients with EBV/latency III/replication and simultaneous PD-L1 expression showed the worst overall survival (P < 0.001). CONCLUSIONS: The PD1/PD-L1 axis is deregulated in post-transplant lymphoproliferative disorders, with frequent PD-L1 expression and PD1 negativity. PD-L1 expression is associated with EBV latency II or III and PD-L1 CNAs, and probably reflects a proinflammatory tumour microenvironment. The combined analysis of EBV status and PD-L1 expression may help to identify deeply immunosuppressed patients who can benefit from immune reconstitution approaches.

J Sports Sci Med ; 17(4): 571-579, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30479525


This study aimed to provide the first description of the whole-body bioimpedance vector of nine non-professional triathletes, and to assess body mass (BM) and vector variations evoked by an ultra-endurance triathlon event. Anthropometric and bioelectrical assessments were performed before (PRE), after (POST), and 48 hours following the race (POST48h). Bioimpedance vector analysis (BIVA) showed triathletes' vectors placed to the left of the major axis and mostly outside the 50% tolerance ellipse of the reference population. Vector migration in POST indicated dehydration, paralleled by a decrease in BM (p = 0.0001). Increased hydration status from POST to POST48h was suggested by a reversed vector migration and increased BM (p = 0.0001). Compared to PRE, POST48h values reflected fluid retention by changes in BIVA, while BM was still lower (p = 0.0001). Racing time was positively related to basal resistance -R/h- (r = 0.68; p = 0.04) and bioimpedance -Z/h- (r = 0.68; p = 0.045). Besides, basal R/h and Z/h were positively related to PRE-to-POST changes of R/h and Z/h (r = 0.80; p = 0.009). PRE-to-POST changes of R/h and Z/h were positively related to racing time (r = 0.80, p = 0.01) and internal workload (r = 0.80, p ≤ 0.02). Notwithstanding the lack of significant correlation between BM and bioelectrical parameters, the vector's behavior was explained from a multifactorial perspective (including BM variations) by using multiple regression analysis. On the other hand, BM changes were not related to racing time, internal workload or energy deficit (ranges: r = - 0.46 to 0.65; p = 0.06 to 0.98). In conclusion, these triathletes exhibit a specific bioelectrical distribution. Furthermore, vector migration was consistent with fluid loss induced by the event. Finally, vector analysis seems to provide additional information about hydration changes 48h after the event in comparison with BM alone.

Ciclismo/fisiologia , Peso Corporal , Impedância Elétrica , Corrida/fisiologia , Natação/fisiologia , Adulto , Antropometria , Atletas , Desidratação , Humanos , Masculino , Resistência Física
PLoS One ; 13(11): e0205226, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30496211


PURPOSE: This study compared subcutaneous adipose tissue (SAT) measurements using a skinfold caliper and Renco Lean-Meater Series 12 A-mode portable ultrasound scanner (A-US). It aimed to assess their inter- and intra-rater reliability and measure the agreement between both methods. METHODS: Eighty-four volunteers of different fitness levels were divided into three groups by Æ©6 skinfolds: G1 ≤ 55 mm (n = 33 males); G2 > 55 mm (n = 32 males); G3 = 98.0 ± 52.3 mm (n = 19 females). Triceps, subscapular, biceps, iliac crest, supraspinal, abdominal, front thigh and medial calf were assessed by ultrasound and skinfolds. Two technicians for both tools performed triplicate measures. Intraclass correlation (ICC), technical error of measurement (TEM) and coefficients of variation (CVs) were applied for test-retest and inter-rater reliability. Non-Parametric statistics were used in order to establish possible statistical differences and correlation between skinfolds thickness and uncompressed subcutaneous adipose tissue thickness from ultrasound. The amount of agreement between both methods was assessed with Lin's coefficient and a scatterplot of all site locations. A Bland-Altman plot was constructed to establish limits of agreement between groups and regression analysis was employed to assess the ability of skinfolds to explain the variance of ultrasound. RESULTS: Test-retest ICC for skinfolds and ultrasound were higher than 0.989 and 0.793, respectively. Inter-rater ICC for skinfolds was 0.999 with a 95% CI of 0.995 to 0.999 and for ultrasound was 0.755 with a much larger 95% CI of 0.622 to 0.841. TEMs (> 8.50%) and CVs (> 6.72%) compromised ultrasound reliability. Statistical differences were found in most of the analysed anatomical sites (p < 0.001) except in biceps G2 (Z = -1.150, p = 0.25) and G3 (Z = -1.309, p = 0.19). Good correlations (r > 0.7, p ≤ 0.05) were reported at almost all anatomical sites and groups except for biceps (G1: Rho = 0.26, p = 0.140) and abdominal (G2: Rho = -0.16, p = 0.38; G3: Rho = 0.43, p = 0.068). Lin's concordance correlation coefficient registered low values of agreement between skinfolds and A-mode ultrasound (ranged from-0.009-0.646). The scatterplot and the estimated regression line drawn through the midst of all anatomical sites of the whole sample had a slope of 0.51 and R2 adjusted = 0.62 was obtained. The combined analysis between the Bland-Altman plot and the linear regression showed that specifically in the G2 and G3 groups, as the SAT increases the differences between skinfolds and ultrasounds measurements also increases. CONCLUSIONS: The Renco Lean-Meater ultrasound is not interchangeable with skinfold measures. Its utility is questionable, particularly for assessing SAT in active adult populations. Its poor test-retest and inter-rater reliability as well as the lack of agreement when compared to the skinfolds would exclude the free use of the A-mode ultrasound scanner in its hypothetical replacing of the classical calipers.

Composição Corporal/fisiologia , Músculo Esquelético/fisiologia , Gordura Subcutânea/fisiologia , Ultrassonografia/métodos , Abdome/fisiologia , Adulto , Braço/fisiologia , Gorduras/metabolismo , Feminino , Humanos , Masculino , Pregas Cutâneas
PLoS One ; 13(6): e0197957, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29879146


BACKGROUND: Bioelectrical impedance vector analysis (BIVA) is a general concept that includes all methodologies used in the analysis of the bioelectrical vector, whereas the "classic" BIVA is a patented methodology included among these methods of analysis. Once this was clarified, the systematic review of the literature provides a deeper insight into the scope and range of application of BIVA in sport and exercise. OBJECTIVE: The main goal of this work was to systematically review the sources on the applications of BIVA in sport and exercise and to examine its usefulness and suitability as a technique for the evaluation of body composition, hydration status, and other physiological and clinical relevant characteristics, ultimately to trace future perspectives in this growing area, including a proposal for a research agenda. METHODS: Systematic literature searches in PubMed, SPORTDiscus and Scopus databases up to July, 2017 were conducted on any empirical investigations using phase-sensitive bioimpedance instruments to perform BIVA within exercise and sport contexts. The search included healthy sedentary individuals, physically active subjects and athletes. RESULT: Nineteen eligible papers were included and classified as sixteen original articles and three scientific conference communications. Three studies analysed short-term variations in the hydration status evoked by exercise/training through whole-body measurements, eleven assessed whole-body body composition changes induced by long-term exercise, four compared athletic groups or populations using the whole-body assessment, and two analysed bioelectrical patterns of athletic injuries or muscle damage through localised bioimpedance measurements. CONCLUSIONS: BIVA is a relatively new technique that has potential in sport and exercise, especially for the assessment of soft-tissue injury. On the other hand, the current tolerance ellipses of "classic" BIVA are not a valid method to identify dehydration in individual athletes and a new approach is needed. "Specific" BIVA, a method which proposes a correction of bioelectrical values for body geometry, emerges as the key to overcome "classic" BIVA limitations regarding the body composition assessment. Further research establishing standardised testing procedures and investigating the relationship between physiology and the bioelectrical signal in sport and exercise is needed.

Impedância Elétrica , Exercício , Esportes , Humanos
PLoS One ; 12(6): e0178819, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28591135


PURPOSE: The assessment of body hydration is a complex process, and no measurement is valid for all situations. Bioelectrical impedance vector analysis (BIVA) has emerged as a relatively novel technique for assessing hydration status in sports. We applied BIVA a) to determine hydration changes evoked by an intense synchronized swimming (SS) training session; b) to characterize the sample of young elite swimmers in relation with a nonathletic reference population; and c) to generate its 50%, 75% and 95% percentiles of the bioelectrical variables. METHODS: Forty-nine elite SS female swimmers of two age categories, comen (Co: 13.9 ± 0.9 years, n = 34) and junior (Jr: 16.3 ± 0.6 years, n = 15), performed a long, high intensity training session. Body mass (BM) and bioelectrical variables (R, resistance; Xc, reactance; PA, phase angle; and Z, impedance module) were assessed pre- and post-training. BIVA was used to characterize 1) the distribution pattern of the bioelectrical vector (BIA vector) for both age groups, and 2) pre- to post-training BIA vector migration. Bioelectrical variables were also correlated with BM change values. RESULTS: Most swimmers were mostly located outside the 75% and some beyond the 95% percentile of the bioelectrical tolerance ellipses of the general population. The BIA vector showed statistically significant differences in both Co (T2 = 134.7, p = 0.0001) and Jr (T2 = 126.2, p < 0.001). Both groups were also bioelectrically different (T2 = 17.6, p < 0.001). After the training session, a decrease in BM (p = 0.0001) and an increase in BIA variables (p = 0.01) was observed. BIVA also showed a significant pre-post vector migration both in Co (T2 = 82.1; p < 0.001) and Jr (T2 = 41.8; p < 0.001). No correlations were observed between BM changes and bioelectrical variables. CONCLUSIONS: BIVA showed specific bioelectrical characteristics in young elite SS athletes. Considering the decrease in BM and the migration of the BIA vector, we conclude that the homeostatic hydration status of these young elite female swimmers was affected by the execution of intense training sessions. From a methodological perspective, BIVA appears to be sensitive enough to detect subtle hydration changes, but further research is needed to ensure its validity and reliability. Moreover, these findings highlight the importance of ensuring adequate fluid intake during training in young SS athletes.

Atletas , Água Corporal/fisiologia , Impedância Elétrica , Natação/fisiologia , Adolescente , Antropometria , Feminino , Humanos
Apunts, Med. esport ; 44(161): 18-28, ene.-mar. 2009. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-61409


Introducción y objetivos: El objeto del presente estudio fue caracterizar, a lo largo de la edad, el comportamiento de la talla y el peso (7-25 años), el somatotipo y la composición corporal (12-18 años), en gimnastas masculinos de élite. Métodos: Basándose en un diseño mixto-longitudinal se analizó de cada una de las variables: a) evolución a lo largo de la edad, y b) diferencias en relación con una muestra de referencia. El somatotipo se analizó mediante el método Heath-Carter, la masa grasa mediante la fórmula de Slaughter y la masa muscular mediante la fórmula de Poort-mans. Resultados: Los gimnastas son significativamente más bajos y ligeros que la muestra de referencia. Además, los mejores gimnastas lo son aún más que el resto de compañeros de entrenamiento, salvo los especialistas en suelo y salto, donde el tren inferior es protagonista. El pico de crecimiento de la talla se produce a la edad de 14 años, a la misma edad que en la muestra de referencia. El 90% de los gimnastas se clasifica en un perfil ecto-mesomórfico. Poseen un porcentaje de masa grasa significativamente inferior al de la muestra de referencia. El somatotipo, la masa libre de grasa y el porcentaje de masa muscular no describen incrementos significativos a lo largo de la edad. Conclusiones: Los gimnastas españoles muestran un patrón de crecimiento, en las variables de estudio analizadas (talla, peso, somatotipo y composición corporal), que responde a la normalidad. Las principales diferencias entre éstos y la muestra de referencia se producen desde las primeras edades analizadas. Todos estos factores sugieren la implicación de un proceso de selección, tanto previo como el que el propio proceso de entrenamiento realiza a lo largo de los años, antes de alcanzar la elite deportiva(AU)

Introduction and aims: The aim of the present study was to characterize the evolution of height and weight (from 7 to 25 years old) and somatotype and body composition (from 12 to 18 years old) in elite male gymnasts. Method: For each of the variables, a mixed-longitudinal design was used to analyze: a) its evolution with age and b) its differences with respect to a reference population. Somatotype was analyzed with the Heath-Carter method, fat free mass with the Slaughter formula and muscle mass with the Poortman formula. Results: Male gymnasts were significantly shorter and lighter than the reference population. The best gymnasts were even more so with respect to their fellow gymnasts, except for specialists in vault and floor where the lower limbs are especially important. The peak height velocity occured at the age of 14, at the same age as in the reference population. The somatotype was ecto-mesomorphic in 90% of the gymnasts. Fat mass percentage was significantly lower than in the reference population. Somatotype, fat free mass and muscle mass showed no significant increases with age. Conclusions: Gymnasts showed a growth pattern considered as normal in the variables analyzed in the present study. The main differences between the gymnasts and the reference group were observed from the beginning of the follow-up. These findings suggest the effects of a selection process, both before and during the training process, before the elite level is reached(AU)

Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Ginástica/fisiologia , Crescimento/fisiologia , Atividade Motora/fisiologia , Peso Corporal/fisiologia , Estatura/fisiologia , Composição Corporal/fisiologia , Somatotipos/fisiologia
Apunts, Med. esport ; 43(159): 118-126, jul.-sept. 2008. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-67830


Introducción y objetivos: Si bien las necesidades nutricionalesy el perfil somático del esgrimista de élite han sidodescritos, no sucede así en jóvenes esgrimistas. El objetivodel presente estudio fue doble: describir el perfil cineantropométricode un grupo de jóvenes esgrimistas de competicióny valorar sus hábitos alimentarios.Métodos: El presente estudio, de carácter observacional ydescriptivo, agrupa las variables analizadas en dos valoraciones:a) valoración nutricional (registro de 24 h): energíatotal, hidratos de carbono, proteínas, lípidos, fibra, colesterol,contenido en agua de la dieta, vitaminas y minerales; b)valoración cineantropométrica: talla, peso, somatotipo ycomposición corporal.Resultados: El 26,3% del grupo se situó por encima de losvalores recomendados de ingesta energética, mientras queel 57,9% lo hizo por debajo. El consumo de hidratos de carbonofue inferior a los valores recomendados, mientras quela ingesta de proteínas y lípidos fue superior. El 89,5 y el63,2% del grupo se situó por debajo de las recomendacionesde grasas monoinsaturadas y poliinsaturadas, respectivamente.El 89,5% registró valores de grasas saturadas porencima de la ingesta recomendada. El consumo de fibra fuedeficitario en el 52,6% de los casos. El consumo de colesterolfue en cambio superior (73,7%). Se registraron valoresde vitaminas acordes con las recomendaciones, no siendoasí en el caso de algunos minerales. Ambos sexos conformangrupos notablemente heterogéneos a nivel somático.Conclusiones: La mayoría de los jóvenes esgrimistas analizadosposeen hábitos alimentarios no adecuados para mantenerun estado de vida saludable ni para la práctica deportiva.Resulta necesario corregir dichos hábitos basándose enuna correcta educación y seguimiento nutricional. Más aún silo que se pretende es optimizar su rendimiento deportivo.La valoración cineantropométrica ratifica estos resultados

Introduction and objectives: Although the nutritional requirements and somatic profile of the elite fencer havebeen described, this information is lacking in young fencers.The aim of the present study was two-fold: firstly, to describethe kinanthropometric profile of a group of youngcompetitive fencers and, secondly, to assess their nutritionalhabits.Methodology: The present observational, descriptivestudy classified the variables analyzed into two categories:a) nutritional assessment (24 h recording): total energy,carbohydrates, proteins, lipids, fiber, cholesterol, dietarywater content, vitamins and minerals; b) kinanthropometricassessment: height, weight, somatotype, and body composition.Results: Total energy intake was above recommended levelsin 26.3% of the group and below these levels in 57.9%.Carbohydrate intake was lower than recommended, whereasprotein and lipid intake was higher. Intake of monounsaturatedand polyunsaturated fats was below recommendedlevels in 89.5% and 63.2% of young fencers,respectively. Saturated fat intake was higher than recommendedintake in 89.5% of the fencers. Fiber consumptionwas deficient in 52.6% of the fencers. In contrast, cholesterolintake was higher than recommended consumption in73.7%. Vitamin intake was in line with recommended levelsbut intake of some minerals was deficient. Both sexes wereremarkably heterogeneous in somatic profile.Conclusions: Nutritional habits in most of the young fencersanalyzed were unsuitable both to maintain a state ofhealth and to practice sport. These habits should be correctedthrough proper education and nutritional follow-upwith further interventions to optimize sports performance.The kinanthropometric assessment confirms these results

Humanos , Masculino , Feminino , Adolescente , Antropometria/métodos , Medicina Esportiva/métodos , Valor Nutritivo , Estado Nutricional , Comportamento Alimentar/fisiologia , Sinais e Sintomas , Nutrição em Saúde Pública/fisiologia , Vigilância Nutricional , Educação Alimentar e Nutricional , Avaliação Nutricional , Estudos Transversais , Micronutrientes/fisiologia