Examination of fatigue development in elite soccer in a hot environment: a multi-experimental approach.

The study examines fatigue in elite soccer played in hot conditions. High-profile soccer players (n=20) were studied during match play at ∼31 °C. Repeated sprint and jump performances were assessed in rested state and after a game and activity profile was examined. Additionally, heart rate (HR), blood lactate, muscle temperature and body mass changes were determined. Repeated sprint and jump performances were reduced (P<0.05) by 2.6% and 8.2%, respectively, after the game. The fatigue index in the repeated sprint test was 6.0±0.7% after the game compared with 1.7±1.0% at rest (P<0.05). High-intensity running was 57±4% lower (P<0.05) during the last 15-min interval of the game compared with the first 15-min period. No differences were observed in mean HR or blood lactates between halves. Muscle temperature was 40.5±0.4 °C after the first half, which was 0.8±0.2 °C higher (P<0.05) than after the second half. Net fluid loss during the game was >2% of the body mass. Correlations were observed between net-fluid loss and repeated sprint test fatigue index after the game (r=0.73, P<0.05) and Yo-Yo intermittent recovery, level 1 test performance and high-intensity running during the final 15 min of the game (r=0.51, P<0.05). The study provides direct evidence of compromised repeated sprint and jump performances induced by soccer match play and pronounced reduction in high-intensity running toward the end of an elite game played in a hot environment. This fatigue could be associated training status and hyperthermia/dehydration.

Restoration of coral populations in light of genetic diversity estimates.

Due to the importance of preserving the genetic integrity of populations, strategies to restore damaged coral reefs should attempt to retain the allelic diversity of the disturbed population; however, genetic diversity estimates are not available for most coral populations. To provide a generalized estimate of genetic diversity (in terms of allelic richness) of scleractinian coral populations, the literature was surveyed for studies describing the genetic structure of coral populations using microsatellites. The mean number of alleles per locus across 72 surveyed scleractinian coral populations was 8.27 (±0.75 SE). In addition, population genetic datasets from four species (Acropora palmata, Montastraea cavernosa, Montastraea faveolata and Pocillopora damicornis) were analyzed to assess the minimum number of donor colonies required to retain specific proportions of the genetic diversity of the population. Rarefaction analysis of the population genetic datasets indicated that using 10 donor colonies randomly sampled from the original population would retain >50% of the allelic diversity, while 35 colonies would retain >90% of the original diversity. In general, scleractinian coral populations are genetically diverse and restoration methods utilizing few clonal genotypes to re-populate a reef will diminish the genetic integrity of the population. Coral restoration strategies using 10-35 randomly selected local donor colonies will retain at least 50-90% of the genetic diversity of the original population.

pH-Gated photoresponsive shuttling in a water-soluble pseudorotaxane.

A fluorescent bistable pseudorotaxane was devised and shown to display pH-gated photoresponsive ring shuttling. At pH > 7.5 shuttling does not take place after light stimulation while at pH ≈ 5 the macrocycle is quantitatively translocated.

Endovascular occlusion of intracranial aneurysms with electrically detachable coils: correlation of aneurysm neck size and treatment results.

PURPOSE: To devise a method to measure aneurysm neck size on angiographic films, and to correlate the sizes obtained with the extent of endovascular aneurysm occlusion, performed with electrically detachable coils. METHODS: The angiograms of 79 intracranial aneurysms treated by endovascular occlusion using electrically detachable coils were retrospectively analyzed. A method using the average reported caliber of the major intracranial vessels was applied to determine the aneurysm neck sizes on the diagnostic angiograms. The cases were divided into two groups according to neck size, 4 mm being the discriminative value for small and wide necks. The posttreatment angiogram of each case was analyzed to evaluate the degree of occlusion achieved by the technique. RESULTS: Necks were successfully measured in 95% of the aneurysms. Complete aneurysm thrombosis was observed in 85% of the small-necked aneurysms and in 15% of the wide-necked aneurysms. CONCLUSIONS: Accurate angiographic measurements of neck diameter can be obtained in most aneurysms. The size of an aneurysm neck correlates well with the results of the endovascular treatment. Small-necked aneurysms can be satisfactorily occluded with this technique. In wide-necked aneurysms this technique should be reserved for lesions having a high surgical risk.

Patency and flow of the internal jugular vein after functional neck dissection.

OBJECTIVES: To assess the patency and flow of the internal jugular vein after functional neck dissection. STUDY DESIGN: Prospective study of 54 internal jugular veins in 29 oncologic patients undergoing functional neck dissection between September 1994 and February 1997. METHODS: Patency, presence of thrombosis, characteristics of the vein wall, compressibility, area of the vein both in rest and during Valsalva maneuver, expiratory flow speed, Valsalva flow speed, jugular flow in each side, and total jugular flow were assessed in all veins before and after dissection. All patients were evaluated before and after the procedure by means of duplex Doppler ultrasonography. RESULTS: In no case was there thrombosis before or after the operation. Although total jugular flow decreases during the early postoperative period, it recovers to normal parameters within 3 months after surgery. CONCLUSIONS: According to these results, the patency of the internal jugular vein remains unaltered after functional neck dissection. Ultrasonographically there is no thrombosis after this procedure.

[Blood flow changes in the internal jugular veins after oncological neck surgery without lymph node dissection]. / Cambios de flujo en las venas yugulares internas tras cirugía oncológica cervical no ganglionar.

The effect of oncological surgery of the head and neck area without lymph node dissection on the patency and blood flow of the internal jugular veins (IJV) was assessed in a prospective study. Ten IJV of 8 patients who underwent surgery between September 1994 and February 1997 were evaluated. Ultrasound Doppler (UD) of both IJV was performed before and after surgery. Mean age of patients was 56.3 years (range, 38 to 72 years), and all but one were men. There was no case of postoperative thrombosis. No significant differences were found between the preoperative and postoperative measurements. Consequently, oncological surgery of the head and neck area without lymph node dissection did not seem to affect the patency and UD characteristics of the IJV.

Periosteal glomus tumor of the femur: a case report.

Osseous abnormalities produced by glomus tumors located in soft tissues of the periungual region have been described. More rare is the location of a glomus tumor within bone, which usually is located in the phalanx of the fingers. However, to the authors' knowledge, there is no previous description of a glomus tumor located in a periosteal location of a long bone. A 50-year-old man with a glomus tumor in a periosteal location of the lower metaphysis of the femur without neoplastic erosion of the cortical surface is reported. Magnetic resonance imaging and intraoperative ultrasonography were needed to locate the lesion.