ABSTRACT
Peripheral nerve sheath tumors (PNST) comprise schwannomas and neurofibromas. The finding of increased adipose tissue around benign PNSTs has been described as the "split fat sign" on magnetic resonance imaging exams, which is suggestive of an intramuscular or intermuscular location of the tumor. However, few studies have described this sign as a salient ultrasound feature of PNSTs. The main purpose of this study was to retrospectively evaluate the presence of increased fatty tissue deposition around benign PNSTs diagnosed by high-resolution ultrasound. In addition, we aimed to corroborate the presence of vascularization around the affected area. A retrospective analysis of ten cases of PNSTs and two cases of post-traumatic neuromas diagnosed by high-resolution ultrasound was performed with a Logiq® P8 ultrasound with a 2-11 MHz multifrequency linear probe L3-12-D (central frequency: 10 MHz). Localized types of neurofibromas and schwannomas in any location were seen as predominantly hypoechoic tumors with an oval or fusiform shape. Exiting and entering nerves (tail sign) were observed in six cases, showing localized lesions both in intermuscular and subcutaneous locations. The presence of increased hyperechoic tissue (the split fat sign) was noted in cases of solitary intermuscular and intramuscular peripheral nerve sheath tumors, mainly the schwannomas. Though small tumors did not demonstrate the tail sign, the increase in adipose tissue and vascularity on US was well demonstrated. In conclusion, the nerve in continuity forms the basis of the ultrasonographic diagnosis of PNSTs. However, high-resolution US can convincingly demonstrate the increased presence of fat in the upper and lower poles as well as circumferentially in intermuscular or intramuscular benign PNSTs.
ABSTRACT
Introducción: Las hormonas sexuales femeninas propias del ciclo menstrual no solo tienen funciones reproductivas, tambiéninfluyen en otros sistemas fisiológicos pudiendo afectar al rendimiento deportivo y cognitivo. El propósito del presente estudioha sido evaluar distintos aspectos como la composición corporal, la resistencia, la fuerza muscular y algunas capacidadescognitivas en diferentes etapas del ciclo menstrual. Material y método: En el estudio participaron ocho mujeres jóvenes eumenorreicas (edad = 23,1 ± 4,4 años) con ciclosmenstruales regulares. Se realizó una prueba de densitometría y una bioimpedancia para estudiar la composición corporal, unaprueba de memoria visual a corto plazo y un test de tiempo de reacción para evaluar habilidades cognitivas y se analizaroncaracterísticas del músculo (grosor y rigidez del recto anterior y fuerza muscular) junto a una prueba de esfuerzo para evaluarel rendimiento durante las fases folicular media (FF) y lútea media (FL) del ciclo menstrual de las participantes. Resultados: Durante la fase folicular las participantes registraron un mayor tiempo total (FF = 488,5 ± 93,18 s vs. FL = 468,6± 81,29 s; p = 0,015) y una frecuencia cardiaca inicial menor (FF = 83,3 ± 10,23 PPM vs. FL = 92,9 ± 7,67 PPM; p = 0,034) en laprueba de esfuerzo. Además, Respecto a las habilidades cognitivas, en la fase folicular se obtuvieron mejores resultados enel tiempo de reacción tanto con la mano derecha (FF = 0,426 ± 0,082 s vs. FL = 0,453 ± 0,087 s; p = 0,036) como con la manoizquierda (FF = 0,435 ± 0,096 s vs. FL = 0,466 ± 0,077 s; p = 0,034). Por otro lado, se encontró un mayor porcentaje de grasa(FF = 27,3 ± 5,1% vs. FL = 27,9 ± 5,0%; p = 0,041) en la fase lútea. Conclusión: El rendimiento en resistencia y en aspectos cognitivos como es el tiempo de reacción fue mejor en la FaseFolicular mientras que se observó un mayor porcentaje de grasa en la Fase Lútea. Sin embargo, la memoria, la fuerza y lascaracterísticas...(AU)
Introduction: The female sexual hormones typical of the menstrual cycle not only have reproductive functions, they alsoinfluence other physiological systems and can affect sports and cognitive performance. The purpose of this study has beento evaluate different aspects such as body composition, endurance, muscle strength and some cognitive abilities at differentstages of the menstrual cycle. Material and method: Eight young eumenorrheic women (age = 23.1 ± 4.4 years) with regular menstrual cycles participatedin the study. A densitometry and bioimpedance test were performed to study body composition, a short-term visual memorytest and a reaction time test to assess cognitive abilities, and muscle characteristics (thickness and stiffness of the anteriorrectus and muscle strength) along with a progressive test to exhaustion were analyzed to assess performance during themid-follicular (FF) and mid-luteal (FL) phases of the participants menstrual cycle. Results: During the follicular phase, the participants registered a greater total time (FF = 488.5 ± 93.18 s vs. FL = 468.6 ± 81.29 s;P = 0.015) and a lower initial heart rate (FF = 83.3 ± 10.23 PPM vs. FL = 92.9 ± 7.67 PPM; P = 0.034) in the progressive test toexhaustion. Regarding cognitive abilities, in the follicular phase, better results were obtained in reaction time both with theright hand (FF = 0.426 ± 0.082 s vs. FL = 0.453 ± 0.087 s; P = 0.036) and with the left hand (FF = 0.435 ± 0.096 s vs. FL = 0.466 ±0.077 s; P = 0.034). On the other hand, a higher percentage of fat (FF = 27.3 ± 5.1% vs. FL = 27.9 ± 5.0%; P = 0.041) was foundin the luteal phase. Conclusion: Performance in endurance and in cognitive test, such as reaction time was better in the Follicular Phase, whilea higher percentage of fat was observed in the Luteal Phase. However, memory, strength and muscular characteristics werenot affected by the hormonal fluctuations of the menstrual cycle.(AU)
Subject(s)
Humans , Female , Young Adult , Adult , Menstrual Cycle/psychology , Physical Functional Performance , Cognition , Motor Activity , Follicular Phase , Corpus Luteum , Sports Medicine , Psychology, Sports , Densitometry , MenstruationABSTRACT
α-Actinin-3 is a protein with a structural role at the sarcomeric Z-line in skeletal muscle. As it is only present in fast-type muscle fibers, α-actinin-3 is considered a key mechanical component to produce high-intensity muscle contractions and to withstand external tension applied to the skeletal muscle. α-Actinin-3 is encoded by the gene ACTN3, which has a single-nucleotide polymorphism (p.R577X; rs1815739) that affects the expression of α-actinin-3 due to the presence of a stop codon. Individuals homozygous for the 577R allele (i.e., RR genotype) and RX heterozygotes express functional α-actinin-3, while those homozygous for the 577X (i.e., XX genotype) express a non-functional protein. There is ample evidence to support the associations between the ACTN3 genotype and athletic performance, with higher frequencies of the 577R allele in elite and professional sprint and power athletes than in control populations. This suggests a beneficial influence of possessing functional α-actinin-3 to become an elite athlete in power-based disciplines. However, no previous investigation has determined the frequency of the ACTN3 genotypes in elite badminton players, despite this sport being characterized by high-intensity actions of intermittent nature such as changes of direction, accelerations, jumps and smashes. The purpose of this study was to analyze ACTN3 R577X genotype frequencies in professional badminton players to establish whether this polymorphism is associated with elite athlete status. A total of 53 European Caucasian professional badminton players competing in the 2018 European Badminton Championships volunteered to participate in the study. Thirty-one were men (26.2 ± 4.4 years) and twenty-two were women (23.4 ± 4.5 years). Chi-squared tests were used to analyze the differences in the distribution of ACTN3 genotypes (RR, RX and XX) between categories and sexes. The ACTN3 RR genotype was the most frequent in the sample of professional badminton players (RR = 49.1%, RX = 22.6% and XX = 28.3%). None of the badminton players ranked in the world's top ten possessed the XX genotype (RX = 60%, RR = 40%). The distribution of the ACTN3 genotypes was similar between male and female professional badminton players (men: RR = 45.2%, RX = 25.8% and XX = 29.0%; women: RR = 54.5%, RX = 18.2% and XX = 27.3%; χ2 = 0.58; p = 0.750). The distribution of the ACTN3 genotypes in badminton players was different from the 1000 genome database for the European population (χ2 = 15.5; p < 0.001), with an overrepresentation of the RR genotype (p < 0.05) and an underrepresentation of the RX genotype (p < 0.01). In conclusion, the expression of functional α-actinin-3, associated with RR and RX genotypes in the ACTN3 gene may confer an advantage for reaching the status of elite athlete in badminton, and especially the world's top-ten ranking. Large-scale studies with different ethnic backgrounds are needed to confirm the association of the R allele of ACTN3 with badminton performance.
