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1.
J Theor Probab ; 37(1): 209-227, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38483969

RESUMEN

Let X1,X2,… be independent random variables with EXk=0 and σk2:=EXk2<∞ (k≥1). Set Sk=X1+⋯+Xk and assume that sk2:=ESk2→∞. We prove that under the Kolmogorov condition |Xn|≤Ln,Ln=o(sn/(loglogsn)1/2)we have 1logsn2∑k=1nσk+12sk2fSksk→12π∫Rf(x)e-x2/2dxa.s.for any almost everywhere continuous function f:R→R satisfying |f(x)|≤eγx2, γ<1/2. We also show that replacing the o in (1) by O, relation (2) becomes generally false. Finally, in the case when (1) is not assumed, we give an optimal condition for (2) in terms of the remainder term in the Wiener approximation of the partial sum process {Sn,n≥1} by a Wiener process.

2.
J Lond Math Soc ; 108(2): 409-440, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38515864

RESUMEN

Random walks on the circle group R/Z whose elementary steps are lattice variables with span α∉Q or p/q∈Q taken mod Z exhibit delicate behavior. In the rational case, we have a random walk on the finite cyclic subgroup Zq, and the central limit theorem and the law of the iterated logarithm follow from classical results on finite state space Markov chains. In this paper, we extend these results to random walks with irrational span α, and explicitly describe the transition of these Markov chains from finite to general state space as p/q→α along the sequence of best rational approximations. We also consider the rate of weak convergence to the stationary distribution in the Kolmogorov metric, and in the rational case observe a phase transition from polynomial to exponential decay after ≈q2 steps. This seems to be a new phenomenon in the theory of random walks on compact groups. In contrast, the rate of weak convergence to the stationary distribution in the total variation metric is purely exponential.

3.
J Clin Med ; 13(8)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38673520

RESUMEN

Background: After the increasingly common anterior cruciate ligament reconstruction (ACLR) procedure in competitive athletes, rehabilitation is crucial for facilitating a timely return to sports (RTS) and preventing re-injury. This pilot study investigates the patient-reported outcomes of postoperative rehabilitation in competitive athletes, comparing supervised rehabilitation (SVR) and home-based rehabilitation (HBR). Methods: After ACLR, 60 (out of 74 screened) athletes were recruited and equally divided into HBR and SVR groups using non-probability convenience sampling, with each group comprising 15 males and 15 females. The rehabilitation outcomes in the respective groups were evaluated at 8 months using measures (Tegner Activity Scale [TAS], International Knee Documentation Committee subjective knee form [IKDC-SKF], ACL Return to Sport after Injury [ACL-RSI]) and objective parameters (isometric muscle strength, hamstring/quadricep asymmetry). RTS was evaluated at 9 months, with ACL re-injury rates recorded approximately 6 months post-RTS. Results: Both groups exhibited decreased TAS scores (HBR: 8 to 6, SVR: 8 to 7), with the SVR group demonstrating superior postoperative IKDC-SKF scores (81.82 vs. 68.43) and lower ACL-RSI scores (49.46 vs. 55.25). Isometric and isokinetic muscle strength, along with asymmetry values, was higher in the SVR group 8 months post-ACLR (p < 0.05). The SVR group showed a higher RTS rate to the same level (76.6% vs. 53.3%), while the re-injury rate was the same in both the rehabilitation groups (3.3%). Conclusions: Although both rehabilitation approaches yielded comparable outcomes, SVR may demonstrate some superior biomechanical improvements in athletes, resulting in a higher RTS rate. However, the psychological outcomes and re-injury rates did not significantly differ between the groups, emphasizing the need to address individual psychological needs during rehabilitation. Further investigation is recommended with a larger sample size to address the differences of gender among competitive athletes.

4.
J Funct Morphol Kinesiol ; 7(2)2022 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-35736014

RESUMEN

Unaccustomed or strenuous eccentric exercise is known to cause delayed-onset muscle soreness. A recent hypothesis postulated that mechano-energetic microinjury of the primary afferent sensory neuron terminals in the muscle spindles, namely a transient Piezo2 channelopathy, could be the critical cause of delayed-onset muscle soreness in the form of a bi-phasic non-contact injury mechanism. This theory includes that this microlesion could delay the medium-latency response of the stretch reflex. Our aim with this study was to investigate this hypothesis. According to our knowledge, no study has examined the effect of delayed-onset muscle soreness on the medium-latency response of the stretch reflex. Our findings demonstrated that a significant delay in the medium-latency stretch reflex could be observed right after a multi-stage fitness test in the quadriceps femoris muscles of Hungarian professional handball players who consequently experienced delayed-onset muscle soreness. The long-latency stretch reflex and most likely short-latency stretch reflex were unaffected by delayed-onset muscle soreness in our study, which is in line with earlier findings. We translate these findings as indicative of proprioceptive Type Ia terminal microdamage in the muscle spindle in line with the aforementioned new acute non-contact compression axonopathy theory of delayed-onset muscles soreness.

5.
BMC Sports Sci Med Rehabil ; 13(1): 149, 2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34823577

RESUMEN

BACKGROUND: Anterior cruciate ligament injury arises when the knee anterior ligament fibers are stretched, partially torn, or completely torn. Operated patients either end up re-injuring their reconstructed anterior cruciate ligament or majority develop early osteoarthritis regardless of the remarkable improvements of surgical techniques and the widely available rehabilitation best practices. New mechanism theories of non-contact anterior cruciate ligament injury and delayed onset muscle soreness could provide a novel perspective how to respond to this clinical challenge. MAIN BODY: A tri-phasic injury model is proposed for these non-contact injuries. Mechano-energetic microdamage of the proprioceptive sensory nerve terminals is suggested to be the first-phase injury that is followed by a harsher tissue damage in the second phase. The longitudinal dimension is the third phase and that is the equivalent of the repeated bout effect of delayed onset muscle soreness. Current paper puts this longitudinal injury phase into perspective as the phase when the long-term memory consolidation and reconsolidation of this learning related neuronal injury evolves and the phase when the extent of the neuronal regeneration is determined. Reinstating the mitochondrial energy supply and 'breathing capacity' of the injured proprioceptive sensory neurons during this period is emphasized, as avoiding fatigue, overuse, overload and re-injury. CONCLUSIONS: Extended use, minimum up to a year or even longer, of a current rehabilitation technique, namely moderate intensity low resistance stationary cycling, is recommended preferably at the end of the day. This exercise therapeutic strategy should be a supplementation to the currently used rehabilitation best practices as a knee anti-aging maintenance effort.

6.
Life (Basel) ; 11(5)2021 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-34069060

RESUMEN

Anterior cruciate ligament injury occurs when the ligament fibers are stretched, partially torn, or completely torn. The authors propose a new injury mechanism for non-contact anterior cruciate ligament injury of the knee. Accordingly, non-contact anterior cruciate ligament injury could not happen without the acute compression microinjury of the entrapped peripheral proprioceptive sensory axons of the proximal tibia. This would occur under an acute stress response when concomitant microcracks-fractures in the proximal tibia evolve due to the same excessive and repetitive compression forces. The primary damage may occur during eccentric contractions of the acceleration and deceleration moments of strenuous or unaccustomed fatiguing exercise bouts. This primary damage is suggested to be an acute compression/crush axonopathy of the proprioceptive sensory neurons in the proximal tibia. As a result, impaired proprioception could lead to injury of the anterior cruciate ligament as a secondary damage, which is suggested to occur during the deceleration phase. Elevated prostaglandin E2, nitric oxide and glutamate may have a critical neuro-modulatory role in the damage signaling in this dichotomous neuronal injury hypothesis that could lead to mechano-energetic failure, lesion and a cascade of inflammatory events. The presynaptic modulation of the primary sensory axons by the fatigued and microdamaged proprioceptive sensory fibers in the proximal tibia induces the activation of N-methyl-D-aspartate receptors in the dorsal horn of the spinal cord, through a process that could have long term relevance due to its contribution to synaptic plasticity. Luteinizing hormone, through interleukin-1ß, stimulates the nerve growth factor-tropomyosin receptor kinase A axis in the ovarian cells and promotes tropomyosin receptor kinase A and nerve growth factor gene expression and prostaglandin E2 release. This luteinizing hormone induced mechanism could further elevate prostaglandin E2 in excess of the levels generated by osteocytes, due to mechanical stress during strenuous athletic moments in the pre-ovulatory phase. This may explain why non-contact anterior cruciate ligament injury is at least three-times more prevalent among female athletes.

7.
Antioxidants (Basel) ; 9(3)2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-32150878

RESUMEN

According to our hypothesis, delayed onset muscle soreness (DOMS) is an acute compression axonopathy of the nerve endings in the muscle spindle. It is caused by the superposition of compression when repetitive eccentric contractions are executed under cognitive demand. The acute compression axonopathy could coincide with microinjury of the surrounding tissues and is enhanced by immune-mediated inflammation. DOMS is masked by sympathetic nervous system activity at initiation, but once it subsides, a safety mode comes into play to prevent further injury. DOMS becomes manifest when the microinjured non-nociceptive sensory fibers of the muscle spindle stop inhibiting the effects of the microinjured, hyperexcited nociceptive sensory fibers, therefore providing the 'open gate' in the dorsal horn to hyperalgesia. Reactive oxygen species and nitric oxide play a cross-talking role in the parallel, interlinked degeneration-regeneration mechanisms of these injured tissues. We propose that the mitochondrial electron transport chain generated free radical involvement in the acute compression axonopathy. 'Closed gate exercises' could be of nonpharmacological therapeutic importance, because they reduce neuropathic pain in addition to having an anti-inflammatory effect. Finally, DOMS could have an important ontogenetical role by not just enhancing ability to escape danger to survive in the wild, but also triggering muscle growth.

8.
J Sport Health Sci ; 9(5): 405-414, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32780693

RESUMEN

MicroRNAs (miRs) are small regulatory RNA transcripts capable of post-transcriptional silencing of mRNA messages by entering a cellular bimolecular apparatus called RNA-induced silencing complex. miRs are involved in the regulation of cellular processes producing, eliminating or repairing the damage caused by reactive oxygen species, and they are active players in redox homeostasis. Increased mitochondrial biogenesis, function and hypertrophy of skeletal muscle are important adaptive responses to regular exercise. In the present review, we highlight some of the redox-sensitive regulatory roles of miRs.


Asunto(s)
Adaptación Fisiológica , Ejercicio Físico/fisiología , MicroARNs/metabolismo , Músculo Esquelético/metabolismo , Oxidación-Reducción , Animales , Humanos , Biogénesis de Organelos , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal
9.
Biochim Biophys Acta Mol Basis Dis ; 1866(10): 165778, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32222542

RESUMEN

Regular exercise induces a wide range of redox system-associated molecular adaptive responses to the nervous system. The intermittent induction of reactive oxygen species (ROS) during acute exercise sessions and the related upregulation of antioxidant/repair and housekeeping systems are associated with improved physiological function. Exercise-induced proliferation and differentiation of neuronal stem cells are ROS dependent processes. The increased production of brain derived neurotrophic factor (BDNF) and the regulation by regular exercise are dependent upon redox sensitive pathways. ROS are causative and associative factors of neurodegenerative diseases and regular exercise provides significant neuroprotective effects against Alzheimer's disease, Parkinson's disease, and hypoxia/reperfusion related disorders. Regular exercise regulates redox homeostasis in the brain with complex multi-level molecular pathways.


Asunto(s)
Ejercicio Físico/fisiología , Enfermedades Neurodegenerativas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Enfermedad de Alzheimer/metabolismo , Animales , Antioxidantes/metabolismo , Encéfalo/metabolismo , Lesiones Traumáticas del Encéfalo/metabolismo , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Homeostasis , Humanos , Hipoxia/metabolismo , Hipoxia-Isquemia Encefálica , Isquemia/metabolismo , Neuroprotección/fisiología , Oxidación-Reducción , Enfermedad de Parkinson/metabolismo , Accidente Cerebrovascular/metabolismo
10.
Sports Med Health Sci ; 2(2): 55-64, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34189484

RESUMEN

The SARS-CoV-2-caused COVID-19 pandemic has resulted in a devastating threat to human society in terms of health, economy, and lifestyle. Although the virus usually first invades and infects the lung and respiratory track tissue, in extreme cases, almost all major organs in the body are now known to be negatively impacted often leading to severe systemic failure in some people. Unfortunately, there is currently no effective treatment for this disease. Pre-existing pathological conditions or comorbidities such as age are a major reason for premature death and increased morbidity and mortality. The immobilization due to hospitalization and bed rest and the physical inactivity due to sustained quarantine and social distancing can downregulate the ability of organs systems to resist to viral infection and increase the risk of damage to the immune, respiratory, cardiovascular, musculoskeletal systems and the brain. The cellular mechanisms and danger of this "second wave" effect of COVID-19 to the human body, along with the effects of aging, proper nutrition, and regular physical activity, are reviewed in this article.

12.
Free Radic Biol Med ; 132: 33-41, 2019 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-30389495

RESUMEN

The decrease in cognitive/motor functions and physical abilities severely affects the aging population in carrying out daily activities. These disabilities become a burden on individuals, families and society in general. It is known that aging conditions are ameliorated with regular exercise, which attenuates the age-associated decline in maximal oxygen uptake (VO2max), production of reactive oxygen species (ROS), decreases in oxidative damage to molecules, and functional impairment in various organs. While benefits of physical exercise are well-documented, the molecular mechanisms responsible for functional improvement and increases in health span are not well understood. Recent findings imply that exercise training attenuates the age-related deterioration in the cellular housekeeping system, which includes the proteasome, Lon protease, autophagy, mitophagy, and DNA repair systems, which beneficially impacts multiple organ functions. Accumulating evidence suggests that exercise lessens the deleterious effects of aging. However, it seems unlikely that systemic effects are mediated through a specific biomarker. Rather, complex multifactorial mechanisms are involved to maintain homeostatic functions that tend to decline with age.


Asunto(s)
Envejecimiento/fisiología , Ejercicio Físico/fisiología , Oxidación-Reducción , Anciano , Animales , Reparación del ADN , Genes Esenciales/genética , Homeostasis , Humanos , Especies Reactivas de Oxígeno/metabolismo
13.
Am J Sports Med ; 34(2): 220-5, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16210575

RESUMEN

BACKGROUND: The security of the graft fixation is an important factor of anterior cruciate ligament reconstruction, especially in the early postoperative period. HYPOTHESIS: The femoral press-fit fixation technique is a safe, alternative technique for the fixation of the bone-patellar tendon-bone graft. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Between January 1, 1998, and June 30, 2002, 285 patients, with a mean age of 29.1 years, underwent operation and observation in our department. All patients had arthroscopic anterior cruciate ligament reconstruction using bone-patellar tendon-bone graft with femoral press-fit and tibial interference screw fixation. The mean follow-up period was 35.8 months (range, 24-77 months). During each patient's evaluation, a physical examination, a subjective evaluation, the International Knee Documentation Committee and Lysholm scores, KT-1000 arthrometer testing, and radiological evaluation were performed. The paired Student t test or chi(2) test was used for statistical analysis. RESULTS: According to the International Knee Documentation Committee score, 241 patients (85%) had good (46 normal and 195 nearly normal) results, whereas 39 patients had abnormal and 5 patients had severely abnormal overall results. The preoperative mean Lysholm score was 63.5 +/- 12.7 points. At the final examination, the mean value was 93.5 +/- 7.8 points (P < .01). One hundred ninety-seven athletes could return to their previous sports activity level, whereas 13 patients gave up their sports career. The KT-1000 arthrometer results showed a side-to-side difference of 1.91 +/- 2.1 mm at the maximum manual strength tests. CONCLUSION: The femoral press-fit fixation is an alternative fixation method for the bone-patellar tendon-bone graft and provides good stability for the anterior cruciate ligament reconstruction. The use of press-fit fixation technique avoids most interference screw or other hardware-induced complications at the femoral side.


Asunto(s)
Ligamento Cruzado Anterior/cirugía , Artroplastia/métodos , Plastía con Hueso-Tendón Rotuliano-Hueso/métodos , Fijadores Internos , Traumatismos de la Rodilla/cirugía , Adolescente , Adulto , Lesiones del Ligamento Cruzado Anterior , Artroplastia/instrumentación , Plastía con Hueso-Tendón Rotuliano-Hueso/instrumentación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
14.
Neurochem Int ; 46(8): 635-40, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15863241

RESUMEN

We have tested the hypothesis that training with moderate- (MT), strenuous- (ST), or over- (OT) load can cause alterations in memory, lipid peroxidation, protein oxidation, DNA damage, activity of 8-oxoG-DNA glycosylase (OGG1) and brain-derived neurotrophic factor (BDNF), in rat brain. Rat memory was assessed by a passive avoidance test and the ST and OT group demonstrated improved memory. The content of BDNF was increased only in the OT group. The oxidative damage of lipids and DNA, as measured by thiobarbituric acid reactive substances (TBARS), and 8-hydroxydeoxyguanosine (8-OHdG), did not change significantly with exercise. Similarly, the activity of DNA repair enzyme, 8-oxoguanine DNA glycosylase (OGG1), was not altered with exercise training. On the other hand, the content of reactive carbonyl derivatives (RCDs) decreased in all groups and the decrease reached significance levels in the ST and OT groups. The activity of the proteasome complex increased in the brain of OT. The findings of this study imply that over-training does not induce oxidative stress in the brain and does not cause loss of memory. The improved memory was associated with enhanced BDNF content.


Asunto(s)
Encéfalo/metabolismo , Trastornos de la Memoria/etiología , Degeneración Nerviosa/etiología , Estrés Oxidativo/fisiología , Condicionamiento Físico Animal/efectos adversos , 8-Hidroxi-2'-Desoxicoguanosina , Animales , Reacción de Prevención/fisiología , Biomarcadores/metabolismo , Encéfalo/fisiopatología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Daño del ADN/fisiología , ADN Glicosilasas/metabolismo , Reparación del ADN/fisiología , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Peroxidación de Lípido/fisiología , Trastornos de la Memoria/metabolismo , Trastornos de la Memoria/fisiopatología , Degeneración Nerviosa/metabolismo , Degeneración Nerviosa/fisiopatología , Pruebas Neuropsicológicas , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Regulación hacia Arriba/fisiología
15.
Brain Res Bull ; 65(6): 487-93, 2005 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-15862920

RESUMEN

Chronic swimming training and phytotherapeutic supplementation are assumed to alleviate oxidative damage, and support cell survival in the brain. The effect of forced, chronic swimming training, and enriched lab chow containing 1% (w/w) dried nettle (Urtica dioica) leaf were investigated for oxidative stress, inflammation and neurotrophic markers in Wistar rat brains. The rats were divided into groups subjected to swimming training (6 weeks) or to nettle supplementation (8 weeks) or to a combination of these two treatments. The level of oxidative stress was measured by electron spin resonance (EPR), and by the concentration of carbonylated proteins. Nettle supplementation resulted in a decreased concentration of free radicals in both cerebellum and frontal lobe. Swimming, however, did not influence significantly the oxidative damage nor was it reflected in the carbonyl content. The protein content of nerve growth factor (NGF), and brain-derived neurotrophic factors (BDNF) was evaluated by E-Max ImmunoAssay in the cerebellum. No changes occurred either with exercise or nettle diet treatments. On the other hand, nuclear factor kappa B (NF-kappaB) binding activity to DNA increased with the combined effect of swimming training and nettle diet, while the activator protein1 (AP-1) DNA binding activity showed a more profound elevation in the nettle treated animals. The amount of c-Jun decreased by swimming training. In conclusion, the results suggest that both exercise and nettle influenced physiological brain functions. Nettle supplementation reduces the free radical concentration and increases the DNA binding of AP-1 in the brain. Nettle was found to be an effective antioxidant and possible antiapoptotic supplement promoting cell survival in the brain. Exercise, as a downregulator of c-Jun and in combined group as an upregulator of NF-kappaB, may play also a role in antiapoptotic processes, which is important after brain injury.


Asunto(s)
Encéfalo/metabolismo , Estrés Oxidativo/fisiología , Condicionamiento Físico Animal/fisiología , Preparaciones de Plantas/farmacología , Urtica dioica/química , Animales , Conducta Animal , Encéfalo/anatomía & histología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , ADN/metabolismo , Suplementos Dietéticos , Espectroscopía de Resonancia por Spin del Electrón/métodos , Ensayo de Cambio de Movilidad Electroforética/métodos , Inmunoensayo/métodos , FN-kappa B/metabolismo , Factor de Crecimiento Nervioso/metabolismo , Estrés Oxidativo/efectos de los fármacos , Fosforilación , Unión Proteica/fisiología , Proteínas Proto-Oncogénicas c-jun/metabolismo , Ratas , Ratas Wistar , Factor de Transcripción AP-1/metabolismo
16.
Orv Hetil ; 146(10): 471-5, 2005 Mar 06.
Artículo en Húngaro | MEDLINE | ID: mdl-15835345

RESUMEN

INTRODUCTION: The histological properties of the femoral press-fit fixation in anterior cruciate ligament reconstruction have not been extensively examined. The purpose of the study was to analyse the histological properties of the bone-patellar tendon graft in the bone tunnel area during the early stages of healing in an animal model. Furthermore the authors wanted to draw conclusions for the postoperative rehabilitation program on the basis of their data. MATERIAL AND METHODS: ACL reconstruction was performed in pigs using femoral press-fit fixation. After 3 and 6 weeks the incorporation of the bone block in the femur in 2 pigs was histological and radiological evaluated. RESULTS: After 3 and 6 weeks the examination showed almost similar histology on the bony side the grafts except (1) a higher amount of fibrotic tissue in-between the lamellae of the inserted patellar bone after 6 weeks, (2) the presence of direct osseous unions between the two lamellar systems and (3) thicker lamellae at the base than toward the condylar tissue. CONCLUSIONS: Concerning the progression of graft healing by histological findings our study showed, that after 6 weeks the femoral press-fit fixation appear to have good incorporation after ACL reconstruction.


Asunto(s)
Ligamento Cruzado Anterior/cirugía , Artroplastia/métodos , Fémur , Articulación de la Rodilla/patología , Articulación de la Rodilla/fisiopatología , Animales , Ligamento Cruzado Anterior/patología , Ligamento Cruzado Anterior/fisiopatología , Modelos Animales de Enfermedad , Articulación de la Rodilla/cirugía , Periodo Posoperatorio , Rango del Movimiento Articular , Porcinos , Cicatrización de Heridas
17.
Life Sci ; 72(14): 1627-33, 2003 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-12551751

RESUMEN

Reactive oxygen and nitrogen species generated either as products of aerobic metabolism or as a consequence of environmental mutagens, oxidatively modify DNA. Formamidopyrimidine-DNA glycosylase (Fpg) and endonuclease III (endo III) or their functional mammalian homologues repair 7,8-dihydro-8-oxoguanine (8-oxoG) and damaged pyrimidines, respectively, to curb the deleterious effects of oxidative DNA alterations. A single bout of physical exercise can induce oxidative DNA damage. However, its effect on the activity of repair enzymes is not known. Here we report that the activity of a functional homolog of Fpg, human 8-oxoG DNA glycosylase (hOGG1), is increased significantly, as measured by the excision of 32P labeled damaged oligonucleotide, in human skeletal muscle after a marathon race. The AP site repair enzyme did not change significantly. Despite the large individual differences among the six subjects measured, data suggest that a single-bout of aerobic exercise increases the activity of hOGG1 which is responsible for the excision of 8-oxoG. The up-regulation of DNA repair enzymes might be an important part of the regular exercise induced adaptation process.


Asunto(s)
Daño del ADN , Reparación del ADN , Desoxirribonucleasa (Dímero de Pirimidina) , Endodesoxirribonucleasas/genética , Proteínas de Escherichia coli , Músculo Esquelético/enzimología , N-Glicosil Hidrolasas/genética , Carrera , Biopsia , ADN/química , ADN-Formamidopirimidina Glicosilasa , Endodesoxirribonucleasas/metabolismo , Humanos , Masculino , N-Glicosil Hidrolasas/metabolismo
18.
Am J Sports Med ; 32(4): 899-908, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15150035

RESUMEN

BACKGROUND: Tegner and Lysholm described their generally acknowledged activity score in 1985. It was originally tested for knee ligament injuries, but for the past 17 years it has been used for other joint evaluations as well. The development of already existing and new kinds of sports, differences between knee and ankle loading, and different injury rates provided reasons for developing an ankle-specific activity score. HYPOTHESIS: The new score should have a higher reliability, validity, and sensitivity than the Tegner score when evaluating ankle-related activity changes. STUDY DESIGN: Methodological study. METHODS: Fifty-three sports, 3 working activities, and 4 general activities were inserted into a 0-to-10 category system based on the rankings of a 7 x 2-point pre-evaluation system, followed by a direct comparison with the Tegner score and reliability, validity, and sensitivity testing on 2 different patient populations. RESULTS: In direct comparison, there is a strong overall correlation of the 2 activity-scoring systems (r = 0.7565), but the ankle activity score proved to be different from the Tegner score in the higher categories, especially in the top 4 ankle score categories (r = 0.1450). Further tests demonstrated the high reliability (1.00) of the new score. Analysis of variance proved that activity changes measured by the ankle score correspond well to the difference between the patients' subjective results and their Karlsson functional scores (P =.0119). This is not the case when we measure ankle activity changes using the knee-specific Tegner score (P =.0987). Furthermore, ankle score differences spread over a wider range (-1.18 +/- 2.12) than did Tegner score differences (-0.68 +/- 1.29), which demonstrates the higher sensitivity of the new score. CONCLUSIONS: Based on these results, the new ankle activity score could be a better complement in the complex evaluation of ankle instability.


Asunto(s)
Traumatismos en Atletas/diagnóstico , Inestabilidad de la Articulación/diagnóstico , Deportes/clasificación , Adulto , Traumatismos en Atletas/fisiopatología , Femenino , Indicadores de Salud , Humanos , Inestabilidad de la Articulación/fisiopatología , Masculino , Evaluación de Resultado en la Atención de Salud , Pronóstico
19.
Orv Hetil ; 143(50): 2769-73, 2002 Dec 15.
Artículo en Húngaro | MEDLINE | ID: mdl-12583316

RESUMEN

UNLABELLED: The authors have reported the experiences at femoral press-fit fixation technique used in anterior cruciate ligament reconstruction with bone-patellar tendon-bone autograft. Their surgical technique have been described and early results have been compared with those from anterior cruciate ligament plasties with the interference screw fixation technique during a prospective study. PATIENTS AND METHODS: 665 anterior cruciate ligament reconstructions were performed between September 1997 and August 1999 at the Department of Sports Surgery of the National Institute for Sports Medicine. 418 of them were operated on by transtibial technique using free bone--patellar tendon--bone autografts with 265 femoral press-fit and 153 interference screw fixations. 110 patients from the press-fit and 72 from the interference screw group could be followed-up (average follow-up period: 19 months). Physical examination, evaluation by International Knee Documentation Committee and Lysholm scores, radiology, and stability test by KT-1000 arthrometer were used as follow-up tests with statistical comparison. RESULTS: According to the International Knee Documentation Committee score, 77% of the patients with the interference screw and 87% of the patients from the press-fit group turned out to get to the normal or nearly normal categories. Neither the Lachman, anterior drawer and pivot shift tests, nor the results of the KT-1000 measurements have shown statistically significant difference between the two groups of patients. Mild (3-5 degrees) extension deficit has been detected at 14% of the patients with interference screw and 8% of the patients in the press-fit group. Mild (6-15 degrees) flexion deficit has been observed at 22% of the patients with interference screw and 24% of the patients from press-fit group with moderate (16-25 degrees) of flexion deficit at 4% of the patients. The subjective opinions of more than 90% of the patients were that the operation proved to be excellent or good. Based on the functional and stability data of the follow-up study, 87% of the patients operated on with femoral press-fit autograft fixation technique for their anterior cruciate ligament have shown excellent or good results. CONCLUSIONS: When compared with the interference screw technique well-accepted in the literature, no statistically significant difference could be found, therefore this method can be recommended as alternative one for the femoral fixation of the anterior cruciate ligament graft.


Asunto(s)
Ligamento Cruzado Anterior/fisiopatología , Ligamento Cruzado Anterior/cirugía , Articulación de la Rodilla/fisiopatología , Articulación de la Rodilla/cirugía , Procedimientos Ortopédicos/métodos , Trasplante Óseo , Femenino , Fémur/cirugía , Humanos , Masculino , Rótula/cirugía , Rango del Movimiento Articular , Recuperación de la Función , Trasplante Autólogo
20.
Orv Hetil ; 143(5): 235-8, 2002 Feb 03.
Artículo en Húngaro | MEDLINE | ID: mdl-11875836

RESUMEN

INTRODUCTION: Based on the literature data in the last ten years the endoscopic carpal tunnel release seems to be an advantageous alternative method in the treatment of carpal tunnel syndrome. AIMS: Based on minimum 5 year follow-up the authors report the long-term results of endoscopic surgery introduced since 1993. PATIENTS AND METHODS: On 46 hand of 42 patients endoscopic procedure was performed. Thirty-two patients returned to follow-up, they filled out questionnaire, underwent physical examination and 15 patients had electrophysiological test. RESULTS: Twenty-eight patients were without any complaints and symptoms, 3 patients had thenar atrophy. One patient was reoperated on because of residual symptoms. The authors make a comparison between their data and the great experienced Chow's results and they review the literature data of open procedure. CONCLUSIONS: They conclude that the long-term results of the endoscopic surgery are similar to the outcome of the open procedures. The electrophysiologic tests have not always any relationship with the patient's complaints and symptoms.


Asunto(s)
Síndrome del Túnel Carpiano/cirugía , Endoscopía/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
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