Background suppression of electrical activity is a potential biomarker of subsequent brain injury in a rat model of neonatal hypoxia-ischemia.

Electrographic seizures and abnormal background activity in the neonatal electroencephalogram (EEG) may differentiate between harmful versus benign brain insults. Using two animal models of neonatal seizures, electrical activity was recorded in freely behaving rats and examined quantitatively during successive time periods with field-potential recordings obtained shortly after the brain insult (i.e., 0-4 days). Single-channel, differential recordings with miniature wireless telemetry were used to analyze spontaneous electrographic seizures and background suppression of electrical activity after 1) hypoxia-ischemia (HI), which is a model of neonatal encephalopathy that causes acute seizures and a large brain lesion with possible development of epilepsy, 2) hypoxia alone (Ha), which causes severe acute seizures without an obvious lesion or subsequent epilepsy, and 3) sham control rats. Background EEG exhibited increases in power as a function of age in control animals. Although background electrical activity was depressed in all frequency bands immediately after HI, suppression in the ß and γ bands was greatest and lasted longest. Spontaneous electrographic seizures were recorded, but only in a few HI-treated animals. Ha-treated rat pups were similar to sham controls, they had no subsequent spontaneous electrographic seizures after the treatment and background suppression was only briefly observed in one frequency band. Thus, the normal age-dependent maturation of electrical activity patterns in control animals was significantly disrupted after HI. Suppression of the background EEG observed here after HI-induced acute seizures and subsequent brain injury may be a noninvasive biomarker for detecting severe brain injuries and may help predict subsequent epilepsy.NEW & NOTEWORTHY Biomarkers of neonatal brain injury are needed. Hypoxia-ischemia (HI) in immature rat pups caused severe brain injury, which was associated with strongly suppressed background EEG. The suppression was most robust in the ß and γ bands; it started immediately after the HI injury and persisted for days. Thus, background suppression may be a noninvasive biomarker for detecting severe brain injuries and may help predict subsequent epilepsy.

Perspectives in football medicine.

The high injury rate among men's professional football players is well-known. Therefore, the Union of European Football Associations (UEFA) launched an injury study already in 2001. This study, the UEFA Elite Club Injury Study (ECIS), currently includes data from a total of 51 clubs from 18 European countries with more than 14,000 registered injuries. With the 21st World Cup (WC) in Russia just around the corner, we have from our study identified a higher match injury rate and a higher proportion of severe injuries in the European Championships compared to the preceding club competitive seasons. Moreover, we have also recently showed that the muscle injury rate is higher when players are given a recovery window of five days or less between two matches. Considering the congested match schedule of the upcoming WC, it is therefore likely that injuries and fatigue once again will be a topic of discussion this summer.

Vascular characteristics in young women-Effect of extensive endurance training or a sedentary lifestyle.

AIM: To explore whether high-level endurance training in early age has an influence on the arterial wall properties in young women. METHODS: Forty-seven athletes (ATH) and 52 controls (CTR), all 17-25 years of age, were further divided into runners (RUN), whole-body endurance athletes (WBA), sedentary controls (SC) and normally active controls (AC). Two-dimensional ultrasound scanning of the carotid arteries was conducted to determine local common carotid artery (CCA) geometry and wall distensibility. Pulse waves were recorded with a tonometer to determine regional pulse wave velocity (PWV) and pulse pressure waveform. RESULTS: Carotid-radial PWV was lower in WBA than in RUN (P < .05), indicating higher arterial distensibility along the arm. Mean arterial pressure was lower in ATH than in CTR and in RUN than in WBA (P < .05). Synthesized aortic augmentation index (AI@75) was lower among ATH than among CTR (-12.8 ± 1.6 vs -2.6 ± 1.2%, P < .001) and in WBA than in RUN (-16.4 ± 2.5 vs -10.7 ± 2.0%, P < .05), suggesting a diminished return of reflection waves to the aorta during systole. Carotid-femoral PWV and intima-media thickness (IMT), lumen diameter and radial distensibility of the CCA were similar in ATH and CTR. CONCLUSION: Elastic artery distensibility and carotid artery IMT are not different in young women with extensive endurance training over several years and in those with sedentary lifestyle. On the other hand, our data suggest that long-term endurance training is associated with potentially favourable peripheral artery adaptation, especially in sports where upper body work is added. This adaptation, if persisting later in life, could contribute to lower cardiovascular risk.

Injuries in male professional football: A prospective comparison between individual and team-based exposure registration.

Methodological considerations of football injury epidemiology have only scarcely been described. The aim of this study was to evaluate the inter-rater agreement in injury capture rate and injury categorization for data registered in two different prospective injury surveillance audits studying the same two Norwegian male professional football clubs for two consecutive seasons, 2008-2009. One audit used team-based exposure (TBE) recording and the other individual-based exposure (IBE). The number of injuries recorded and corresponding injury rates (injuries/1000 h exposure) were compared between audits. Cohen's kappa and prevalence-adjusted bias-adjusted kappa (PABAK) coefficients were calculated for injury variables. Of 323 injuries included, the IBE audit captured 318 (overall capture rate 98.5%, training 98.9%, match 97.8%) and the TBE audit 303 injuries (overall capture rate 93.8%, training 91.4%, match 97.1%). Agreement analysis showed kappa and PABAK coefficients regarded as almost perfect (> 0.81) for 8 of 9 injury variables, and substantial (ƙ 0.75) for the variable injury severity. In conclusion, the capture rate for training injuries was slightly higher with IBE recording, and inter-agreement in injury categorization was very high.

Ischemic injury suppresses hypoxia-induced electrographic seizures and the background EEG in a rat model of perinatal hypoxic-ischemic encephalopathy.

The relationship among neonatal seizures, abnormalities of the electroencephalogram (EEG), brain injury, and long-term neurological outcome (e.g., epilepsy) remains controversial. The effects of hypoxia alone (Ha) and hypoxia-ischemia (HI) were studied in neonatal rats at postnatal day 7; both models generate EEG seizures during the 2-h hypoxia treatment, but only HI causes an infarct with severe neuronal degeneration. Single-channel, differential recordings of acute EEG seizures and background suppression were recorded with a novel miniature telemetry device during the hypoxia treatment and analyzed quantitatively. The waveforms of electrographic seizures (and their behavioral correlates) appeared virtually identical in both models and were identified as discrete events with high power in the traditional delta (0.1-4 Hz) and/or alpha (8-12 Hz) bands. Although the EEG patterns during seizures were similar in Ha- and HI-treated animals at the beginning of the hypoxic insult, Ha caused a more severe electrographic seizure profile than HI near the end. Analyses of power spectral density and seizure frequency profiles indicated that the electrographic seizures progressively increased during the 2-h Ha treatment, while HI led to a progressive decrease in the seizures with significant suppression of the EEG background. These data show that 1) the hypoxia component of these two models drives the seizures; 2) the seizures during Ha are substantially more robust than those during HI, possibly because ongoing neuronal damage blunts the electrographic activity; and 3) a progressive decrease in background EEG, rather than the presence of electrographic seizures, indicates neuronal degeneration during perinatal HI.

Co-administration of subtherapeutic diazepam enhances neuroprotective effect of COX-2 inhibitor, NS-398, after lithium pilocarpine-induced status epilepticus.

RATIONALE: Seizures during status epilepticus (SE) cause neuronal death and induce cyclooxygenase-2 (COX-2). Pilocarpine-induced SE was used to determine if COX-2 inhibition with NS-398, when administered alone or with diazepam, decreases the duration and/or intensity of SE and/or reduces neuronal injury in the rat hippocampus. METHODS: Electroencephalogram (EEG) electrodes were implanted in male Sprague-Dawley rats. SE was induced with lithium-pilocarpine, and continuous EEG and video monitoring were performed for 24 h. Rats were divided into four groups (n=8-14 rats/group) and received NS-398, diazepam, NS-398 and diazepam, or vehicle 30 min after the first motor seizure. Six hours later, NS-398 injection was repeated in the NS-398 and in the NS-398+diazepam groups. The duration of SE (continuous spiking) and the EEG power in the γ-band were analyzed. FluoroJade B staining in the dorsal hippocampus at 24h after SE was analyzed semi-quantitatively in the CA1, CA3 and hilus. RESULTS: The duration and intensity of electrographic SE was not significantly different across the four groups. In rats treated with NS-398 alone, compared to vehicle-treated rats, neuronal damage was significantly lower compared to vehicle-treated rats in the CA3 (27%) and hilus (27%), but neuroprotection was not detected in the CA1. When NS-398 was administered with diazepam, decreased neuronal damage was further obtained in all areas investigated (CA1: 61%, CA3: 63%, hilus: 60%). CONCLUSIONS: NS-398, when administered 30 min after the onset of SE with a repeat dose at 6h, decreased neuronal damage in the hippocampus. Administration of diazepam with NS-398 potentiates the neuroprotective effect of the COX-2 inhibitor. These neuroprotective effects occurred with no detectable effect on electrographic SE.

Estimated drinking water fluoride exposure and risk of hip fracture: a cohort study.

The cariostatic benefit from water fluoridation is indisputable, but the knowledge of possible adverse effects on bone and fracture risk due to fluoride exposure is ambiguous. The association between long-term (chronic) drinking water fluoride exposure and hip fracture (ICD-7-9: '820' and ICD-10: 'S72.0-S72.2') was assessed in Sweden using nationwide registers. All individuals born in Sweden between January 1, 1900 and December 31, 1919, alive and living in their municipality of birth at the time of start of follow-up, were eligible for this study. Information on the study population (n = 473,277) was linked among the Swedish National In-Patient Register (IPR), the Swedish Cause of Death Register, and the Register of Population and Population Changes. Estimated individual drinking water fluoride exposure was stratified into 4 categories: very low, < 0.3 mg/L; low, 0.3 to 0.69 mg/L; medium, 0.7 to 1.49 mg/L; and high, ≥ 1.5 mg/L. Overall, we found no association between chronic fluoride exposure and the occurrence of hip fracture. The risk estimates did not change in analyses restricted to only low-trauma osteoporotic hip fractures. Chronic fluoride exposure from drinking water does not seem to have any important effects on the risk of hip fracture, in the investigated exposure range.

Neuronal degeneration is observed in multiple regions outside the hippocampus after lithium pilocarpine-induced status epilepticus in the immature rat.

Although hippocampal sclerosis is frequently identified as a possible epileptic focus in patients with temporal lobe epilepsy, neuronal loss has also been observed in additional structures, including areas outside the temporal lobe. The claim from several researchers using animal models of acquired epilepsy that the immature brain can develop epilepsy without evidence of hippocampal neuronal death raises the possibility that neuronal death in some of these other regions may also be important for epileptogenesis. The present study used the lithium pilocarpine model of acquired epilepsy in immature animals to assess which structures outside the hippocampus are injured acutely after status epilepticus. Sprague-Dawley rat pups were implanted with surface EEG electrodes, and status epilepticus was induced at 20 days of age with lithium pilocarpine. After 72 h, brain tissue from 12 animals was examined with Fluoro-Jade B, a histochemical marker for degenerating neurons. All animals that had confirmed status epilepticus demonstrated Fluoro-Jade B staining in areas outside the hippocampus. The most prominent staining was seen in the thalamus (mediodorsal, paratenial, reuniens, and ventral lateral geniculate nuclei), amygdala (ventral lateral, posteromedial, and basomedial nuclei), ventral premammillary nuclei of hypothalamus, and paralimbic cortices (perirhinal, entorhinal, and piriform) as well as parasubiculum and dorsal endopiriform nuclei. These results demonstrate that lithium pilocarpine-induced status epilepticus in the immature rat brain consistently results in neuronal injury in several distinct areas outside of the hippocampus. Many of these regions are similar to areas damaged in patients with temporal lobe epilepsy, thus suggesting a possible role in epileptogenesis.

Recording EEG in immature rats with a novel miniature telemetry system.

Serial EEG recordings from immature rat pups are extremely difficult to obtain but important for analyzing animal models of neonatal seizures and other pediatric neurological conditions as well as normal physiology. In this report, we describe the features and applications of a novel miniature telemetry system designed to record EEG in rat pups as young as postnatal day 6 (P6). First, we have recorded electrographic seizure activity in two animal models of neonatal seizures, hypoxia- and kainate-induced seizures at P7. Second, we describe a viable approach for long-term continuous EEG monitoring of naturally reared rat pups implanted with EEG at P6. Third, we have used serial EEG recordings to record age-dependent changes in the background EEG signal as the animals matured from P7 to P11. The important advantages of using miniature wireless EEG technology are: 1) minimally invasive surgical implantation; 2) a device form-factor that is compatible with housing of rat pups with the dam and littermates; 3) serial recordings of EEG activity; and 4) low power consumption of the unit, theoretically allowing continuous monitoring for up to 2 yr without surgical reimplantation. The miniature EEG telemetry system provides a technical advance that allows researchers to record continuous and serial EEG recordings in neonatal rodent models of human neurological disorders, study the progression of the disease, and then assess possible therapies using quantitative EEG as an outcome measure. This new technical approach should improve animal models of human conditions that rely on EEG monitoring for diagnosis and therapy.

Regional differences in injury incidence in European professional football.

The objective of this study was to investigate regional differences in injury incidence in men's professional football in Europe. A nine-season prospective cohort study was carried out between 2001-2002 and 2009-2010 involving 1357 players in 25 teams from nine countries. Teams were categorized into different regions according to the Köppen-Geiger climate classification system. Teams from the northern parts of Europe (n = 20) had higher incidences of injury overall [rate ratio 1.12, 95% confidence interval (CI) 1.06 to 1.20], training injury (rate ratio 1.16, 95% CI 1.05 to 1.27), and severe injury (rate ratio 1.29, 95% CI 1.10 to 1.52), all statistically significant, compared to teams from more southern parts (n = 5). In contrast, the anterior cruciate ligament injury incidence was lower in the northern European teams with a statistically significant difference (rate ratio 0.43, 95% CI 0.25 to 0.77), especially for noncontact anterior cruciate ligament injury (rate ratio 0.19, 95% CI 0.09 to 0.39). In conclusion, this study suggests that there are regional differences in injury incidence of European professional football. However, further studies are needed to identify the underlying causes.

Stress fractures in elite male football players.

The objective was to investigate the incidence, type and distribution of stress fractures in professional male football players. Fifty-four football teams, comprising 2379 players, were followed prospectively for 189 team seasons during the years 2001-2009. Team medical staff recorded individual player exposure and time-loss injuries. The first team squads of 24 clubs selected by UEFA as belonging to the 50 best European teams, 15 teams of the Swedish Super League and 15 teams playing their home matches on artificial turf pitches were included. In total, 51 stress fractures occurred during 1,180,000 h of exposure, giving an injury incidence of 0.04 injuries/1000 h. A team of 25 players can therefore expect one stress fracture every third season. All fractures affected the lower extremities and 78% the fifth metatarsal bone. Stress fractures to the fifth metatarsal bone, tibia or pelvis caused absences of 3-5 months. Twenty-nine percent of the stress fractures were re-injuries. Players that sustained stress fractures were significantly younger than those that did not. Stress fractures are rare in men's professional football but cause long absences. Younger age and intensive pre-season training appear to be risk factors.

Correlations between clinical variables and gene-expression profiles in carotid plaque instability.

OBJECTIVE: Strokes, a major cause of disability, are often caused by embolism from unstable carotid plaques. The aim of this study was to validate a biobank of human carotid endarterectomies as a platform for further exploration of pathways for plaque instability. For this purpose, we investigated the relationship between clinical parameters of plaque instability and expression of genes previously shown to be associated with either plaque instability or healing processes in the vessel wall. METHODS: A database of clinical information and gene-expression microarray data from 106 carotid endarterectomies were used. RESULTS: Expression of matrix metalloproteinase (MMP)-9 and MMP-7 was 100-fold higher in plaques than in normal artery. In general, genes associated with inflammation (such as RANKL and CD68) were overexpressed in symptomatic compared with asymptomatic plaques. Plaques obtained from patients undergoing surgery within 2 weeks after an embolic event showed up-regulation of genes involved in healing reactions in the vessel wall (including elastin and collagen). Statin treatment, as well as echodense lesions, were associated with a more stable phenotype. CONCLUSION: Here, we demonstrate that gene-expression profiles reflect clinical parameters. Our results suggest that microarray technology and clinical variables can be used for the future identification of central molecular pathways in plaque instability.

Lithium pilocarpine-induced status epilepticus in postnatal day 20 rats results in greater neuronal injury in ventral versus dorsal hippocampus.

Many quantitative animal studies examining the possible relationship between hippocampal neuronal loss and the development of epilepsy have examined only the dorsal hippocampus. The ventral hippocampus, however, represents the more homologous structure to the anterior hippocampus in humans, which is the area associated with the maximal damage in patients with temporal lobe epilepsy. This study tested the hypothesis that the ventral hippocampus has greater neuronal injury than the dorsal hippocampus in an animal model of chemoconvulsant-status epilepticus at postnatal day 20. Status epilepticus was induced in postnatal day 20 Sprague-Dawley rat pups with the chemoconvulsant lithium-pilocarpine and brain tissue was examined with Fluoro-Jade B. Horizontal sections (n=7) favoring a visualization of the ventral hippocampus showed marked Fluoro-Jade B staining in CA1, CA3, and hilar region. Coronal sections favoring a visualization of the dorsal hippocampus did not consistently show as robust a staining pattern in these regions. In coronal sections where both the dorsal and ventral hippocampus could be viewed, greater staining was always seen in ventral versus dorsal hippocampus. Quantitative analysis of cell counts demonstrated a significant difference between ventral and dorsal hippocampus in CA1 and CA3, but not hilus. These results demonstrate that in ventral hippocampus, lithium pilocarpine-induced status epilepticus consistently results in hippocampal neuronal injury in postnatal day 20 rats. This study shows the importance of including the ventral hippocampus in any analysis of seizure-induced hippocampal neuronal injury, and raises concerns about the accuracy of studies quantifying hippocampal neuronal loss when only the dorsal hippocampus is examined.

Expression of fatty acid-binding protein 4/aP2 is correlated with plaque instability in carotid atherosclerosis.

OBJECTIVE: the molecular basis for atherosclerotic plaque vulnerability with high risk of plaque rupture and thromboembolism is complex. We investigated whether clinical estimates of plaque stability correlate with differentially expressed mRNA transcripts within the lesion. METHODS AND RESULTS: endarterectomy samples from patients undergoing surgery for symptomatic and asymptomatic carotid stenosis were prospectively collected and clinical parameters recorded in the Biobank of Karolinska Carotid Endarterectomies. mRNA expression profiling (n = 40) and quantitative RT-PCR (n = 105) revealed increased levels of fatty acid-binding protein 4 (FABP4/aP2) in lesions from patients with recent symptoms of plaque instability compared to asymptomatic patients (array: FC = 2, P < 0.05; RT-PCR: P < 0.05). At the mRNA level, FABP4/aP2 correlated with the cell markers CD36, CD68 and CD163 of monocyte/macrophage lineage as well as with CD4-positive T cells. FABP4/aP2 mRNA expression was also correlated with enzymes of the leukotriene pathway, 5-lipoxygenase and leukotriene A4 hydrolase. In addition, analysis of transcript profiles identified CD52 and adipophilin as the mRNAs with the highest correlation with FABP4/aP2. Expression of FABP4/aP2 by macrophages and CD52 by T cells in the lesion was confirmed by immunohistochemistry. CONCLUSIONS: expression of FABP4/aP2 is increased at the mRNA level in unstable carotid plaques. Immunohistochemical analyses showed localization of FABP4/aP2 to macrophage populations. These FABP4/aP2-positive macrophages constitute an important and prevalent phenotype and could provide a new link between scavenging-mediated lipid uptake and cellular metabolic stress in plaque. In addition FABP4/aP2 correlates with other important signs of inflammation and plaque instability, such as T cells and leukotriene enzymes. Taken together, these results indicate that FABP4/aP2 is a key factor connecting vascular and cellular lipid accumulation to inflammation.

Comparison of injuries sustained on artificial turf and grass by male and female elite football players.

The objective of this study was to compare incidences and patterns of injury for female and male elite teams when playing football on artificial turf and grass. Twenty teams (15 male, 5 female) playing home matches on third-generation artificial turf were followed prospectively; their injury risk when playing on artificial turf pitches was compared with the risk when playing on grass. Individual exposure, injuries (time loss) and injury severity were recorded by the team medical staff. In total, 2105 injuries were recorded during 246,000 h of exposure to football. Seventy-one percent of the injuries were traumatic and 29% overuse injuries. There were no significant differences in the nature of overuse injuries recorded on artificial turf and grass for either men or women. The incidence (injuries/1000 player-hours) of acute (traumatic) injuries did not differ significantly between artificial turf and grass, for men (match 22.4 v 21.7; RR 1.0 (95% CI 0.9-1.2); training 3.5 v 3.5; RR 1.0 (0.8-1.2)) or women [match 14.9 v 12.5; RR 1.2 (0.8-1.8); training 2.9 v 2.8; RR 1.0 (0.6-1.7)]. During matches, men were less likely to sustain a quadriceps strain (P=0.031) and more likely to sustain an ankle sprain (P=0.040) on artificial turf.

Injury incidence and injury patterns in professional football: the UEFA injury study.

OBJECTIVE: To study the injury characteristics in professional football and to follow the variation of injury incidence during a match, during a season and over consecutive seasons. DESIGN: Prospective cohort study where teams were followed for seven consecutive seasons. Team medical staff recorded individual player exposure and time-loss injuries from 2001 to 2008. SETTING: European professional men's football. PARTICIPANTS: The first team squads of 23 teams selected by the Union of European Football Associations as belonging to the 50 best European teams. MAIN OUTCOME MEASUREMENT: Injury incidence. RESULTS: 4483 injuries occurred during 566 000 h of exposure, giving an injury incidence of 8.0 injuries/1000 h. The injury incidence during matches was higher than in training (27.5 vs 4.1, p<0.0001). A player sustained on average 2.0 injuries per season, and a team with typically 25 players can thus expect about 50 injuries each season. The single most common injury subtype was thigh strain, representing 17% of all injuries. Re-injuries constituted 12% of all injuries, and they caused longer absences than non re-injuries (24 vs 18 days, p<0.0001). The incidence of match injuries showed an increasing injury tendency over time in both the first and second halves (p<0.0001). Traumatic injuries and hamstring strains were more frequent during the competitive season, while overuse injuries were common during the preseason. Training and match injury incidences were stable over the period with no significant differences between seasons. CONCLUSIONS: The training and match injury incidences were stable over seven seasons. The risk of injury increased with time in each half of matches.

UEFA injury study: a prospective study of hip and groin injuries in professional football over seven consecutive seasons.

BACKGROUND: Groin injury is a common injury in football and a complicated area when it comes to diagnosis and therapy. There is a lack of comprehensive epidemiological data on groin injuries in professional football. OBJECTIVE: To investigate the incidence, pattern and severity of hip and groin injuries in professional footballers over seven consecutive seasons. STUDY DESIGN: Prospective cohort study. SETTING: European professional football. METHODS: During the 2001/2 to 2007/8 seasons, between nine and 17 clubs per season (23 clubs in total) were investigated, accounting for 88 club seasons in total. Time loss injuries and individual exposure during club and national team training sessions and matches were recorded. MAIN OUTCOME MEASURE: Injury incidence. RESULTS: A total of 628 hip/groin injuries were recorded, accounting for 12-16% of all injuries per season. The total injury incidence was 1.1/1000 h (3.5/1000 match hours vs 0.6/1000 training hours, p<0.001) and was consistent over the seasons studied. Eighteen different diagnostic entities were registered, adductor (n = 399) and iliopsoas (n = 52) related injuries being the most common. More than half of the injuries (53%) were classified as moderate or severe (absence of more than a week), the mean absence per injury being 15 days. Reinjuries accounted for 15% of all registered injuries. In the 2005/6 to 2007/8 seasons, 41% of all diagnoses relied solely on clinical examination. CONCLUSIONS: Hip/groin injuries are common in professional football, and the incidence over consecutive seasons is consistent. Hip/groin injuries are associated with long absences. Many hip/groin diagnoses are based only on clinical examination.

UEFA injury study--an injury audit of European Championships 2006 to 2008.

OBJECTIVE: To study the incidence and nature of injuries at European Championships, to compare training and match injury characteristics and to study differences in injury incidence between tournaments. DESIGN: Team physicians prospectively recorded individual player exposure and time loss injuries during 12 European Championships (men's EURO n = 1, men's Under-21 n = 2, men's Under-19 n = 3, men's Under-17 n = 3, women's Under-19 n = 3) from 2006 to 2008. SETTING: International football tournaments. PARTICIPANTS: 1594 men and 433 women. MAIN OUTCOME MEASUREMENT: Injury incidence. RESULTS: 224 injuries (45 training, 179 match play) were registered among 208 (10%) players. No differences in training injury incidence were seen between tournaments (range 1.3-3.9 injuries/1000 hours). The men's EURO had the highest match injury incidence (41.6 injuries/1000 hours) followed by the men's Under-21 tournaments (33.9). The lowest match injury incidence was seen in the women's Under-19 tournaments (20.5). Training injuries constituted 20% of all injuries and caused 26% of all match unavailability. A greater proportion of match injuries were due to trauma (83 vs 47%, p<0.001) and occurred from player contact (75 vs 48%, p = 0.018) compared to training injuries. A higher frequency of re-injury was found among training injuries than match injuries (20 vs 6%, p = 0.009). CONCLUSIONS: Match injury incidence increased with age, indicating greater risk with higher intensity of play. Training injury incidence was relatively low, but training injuries were responsible for a quarter of all match unavailability and may thus have a profound impact on team performance and should be the object of preventive measures.

Injuries among male and female elite football players.

All 12 female football clubs (228 players) and 11 of 14 male clubs (239 players) in the Swedish premier league were followed prospectively during the 2005 season. Individual exposure (playing time), injuries (time loss), and injury severity (days lost due to injury) were recorded by the team medical staffs. Injury incidence was higher for male players during both training (4.7 vs 3.8 injuries/1000 h, P=0.018) and match play (28.1 vs 16.1, P<0.001). However, no difference was found in the incidence of severe injury (absence >4 weeks) (0.7/1000 h in both groups). The thigh, especially the hamstrings, was the overall most commonly injured region in both sexes, while the hip/groin was more commonly injured in male players and the knee in female players. Knee ligament injuries accounted for 31% and 37% of the total time lost from football for male and female players, respectively. In conclusion, male elite players had a higher injury incidence than their female counterparts although no difference was observed in the incidence of moderate to severe injury. We recommend that preventive measures should be focused on hamstring and knee ligament injury in order to reduce the overall injury burden.

High-resolution comprehensive radiation hybrid maps of the porcine chromosomes 2p and 9p compared with the human chromosome 11.

We are constructing high-resolution, chromosomal 'test' maps for the entire pig genome using a 12,000-rad WG-RH panel (IMNpRH2(12,000-rad))to provide a scaffold for the rapid assembly of the porcine genome sequence. Here we present an initial, comparative map of human chromosome (HSA) 11 with pig chromosomes (SSC) 2p and 9p. Two sets of RH mapping vectors were used to construct the RH framework (FW) maps for SSC2p and SSC9p. One set of 590 markers, including 131 microsatellites (MSs), 364 genes/ESTs, and 95 BAC end sequences (BESs) was typed on the IMNpRH2(12,000-rad) panel. A second set of 271 markers (28 MSs, 138 genes/ESTs, and 105 BESs) was typed on the IMpRH(7,000-rad) panel. The two data sets were merged into a single data-set of 655 markers of which 206 markers were typed on both panels. Two large linkage groups of 72 and 194 markers were assigned to SSC2p, and two linkage groups of 84 and 168 markers to SSC9p at a two-point LOD score of 10. A total of 126 and 114 FW markers were ordered with a likelihood ratio of 1000:1 to the SSC2p and SSC9p RH(12,000-rad) FW maps, respectively, with an accumulated map distance of 4046.5 cR(12,000 )and 1355.2 cR(7,000 )for SSC2p, and 4244.1 cR(12,000) and 1802.5 cR(7,000) for SSC9p. The kb/cR ratio in the IMNpRH2(12,000-rad) FW maps was 15.8 for SSC2p, and 15.4 for SSC9p, while the ratio in the IMpRH(7,000-rad) FW maps was 47.1 and 36.3, respectively, or an approximately 3.0-fold increase in map resolution in the IMNpRH(12,000-rad) panel over the IMpRH(7,000-rad) panel. The integrated IMNpRH(12,000-rad) andIMpRH(7,000-rad) maps as well as the genetic and BAC FPC maps provide an inclusive comparative map between SSC2p, SSC9p and HSA11 to close potential gaps between contigs prior to sequencing, and to identify regions where potential problems may arise in sequence assembly.