Blood pressure and hypertension in athletes: a systematic review.

OBJECTIVE: Hypertension is reported to be the most prevalent risk factor for cardiovascular disease in elite athletes. We aimed to review blood pressure (BP) and prevalence of hypertension in different elite athletes, and study whether there was an association between high BP and left ventricular hypertrophy (LVH). METHODS: A systematic review of studies reporting BP in athletes using search strategies developed for PubMed and EMBASE, including only studies with ≥100 participants. We collected data on BP, prevalence of hypertension, LVH and methods of BP measurement. RESULTS: Of 3723 records identified, 51 met the inclusion criteria. These included men and women (n=138,390), aged mostly between 18 and 40 years, from varied sports disciplines. Mean systolic BP varied from 109±11 to 138±7 mm Hg and mean diastolic BP from 57±12 to 92±10 mm Hg. Strength-trained athletes had higher BP than endurance-trained athletes (131.3±5.3/77.3±1.4 vs 118.6±2.8/71.8±1.2 mm Hg, p<0.05), and there was a trend towards a higher BP in athletes training ≥10 h compared with others (121.8±3.8/73.8±2.5 vs 117.6±3.3/66.8±6.9, p=0.058), but overall there was no significant difference in BP between athletes and controls. The prevalence of hypertension varied from 0% to 83%. Some studies showed an association between high BP and LVH. Measurement methods were poorly standardised. CONCLUSIONS: BP and prevalence of hypertension in athletes varied considerably partly because of variations in methodology, but type and intensity of training may contribute towards higher BP. High BP may be associated with LVH.

Prevalence of abnormal ECGs in male soccer players decreases with the Seattle criteria, but is still high.

Electrocardiogram (ECG) and echocardiography are mandatory in preparticipation cardiac screening in soccer players. Abnormal ECG findings usually require follow-up investigations. The main aim of this study was to compare the prevalence of abnormal ECG findings in male professional soccer players according to European Society of Cardiology's (ESC) recommendations and the Seattle criteria, and to assess the need for echocardiography. ECGs from 587 of 595 (99%) players were recorded with ClickECG, and measurements were derived with visually adjusted on-screen calipers on the computer-based averaged PQRST complex. Echocardiographic recordings were performed with Vivid 7/i and categorized according to reference values for athlete's heart. After the initial screening, 32 (5.5%) players were recommended for follow-up. The prevalence of abnormal ECGs was 29.3% vs 11.2% according to the ESC's recommendations and the Seattle criteria, respectively. None of the players with abnormal ECGs only according to the ESC's recommendations had abnormal echocardiograms. Echocardiography alone detected one player with abnormalities (athlete's heart). The Seattle criteria reduced the number of athletes with abnormal ECGs considerably compared with the ESC recommendations. Based on echocardiographic evaluations, this increased the specificity of the Seattle criteria, without increasing the number of false-negative ECGs. The need for mandatory echocardiography in soccer players seems limited.

Visual or computer-based measurements: important for interpretation of athletes' ECG.

BACKGROUND: ECG is recommended for preparticipation health examination in athletes. Owing to a lack of consensus on how to read and interpret athletes' ECGs, different criteria for abnormality are used. AIMS: To compare the prevalence of abnormal ECGs and test the correlation between visual and computer-based measurements. METHODS: In a preparticipation cardiac screening examination of 595 male professional soccer players aged 18-38 years, ECGs were categorised according to the European Society of Cardiology's (ESC) recommendations and the Seattle criteria, respectively. Visual measurements were conducted with callipers on-screen on the averaged PQRST complex in each lead, calculated by the trimmed mean. Computer-based measurements were derived from the medium beat. Heart rhythm and conduction were scored visually by a cardiologist. Categorical variables were compared by κ statistics (K) and continuous variables by intraclass correlation. RESULTS: ECGs of good quality were available from 579 players. According to the ESC's recommendations and Seattle criteria, respectively, ECGs were categorised as abnormal in 171 (29.5%) vs 64 (11.1%) players after visual assessment, and in 293 (50.6%; K=0.395) vs 127 (21.9%; K=0.564) after computer-based measurements. Intraclass correlation was very good for measurements of R and S wave amplitudes and moderate to very good for intervals. K was very good for pathological Q wave amplitudes and moderate for T wave inversions. CONCLUSIONS: Abnormal ECGs were more than twice as common after computer-based than after visual measurements. Such a difference will markedly influence the number of athletes who need further examinations. Reference values may need adjustments dependent on measurement methods.

Residual inorganic soil nitrogen in grass and maize on sandy soil.

Nitrogen (N) remaining as inorganic ('mineral') soil N at crop harvest (N(minH)) contributes to nitrate leaching. N(minH) data from 20 (grass) and 78 (maize) experiments were examined to identify main determinants of N(minH). N-rate (A) explained 51% (grass) and 34% (maize) of the variance in N(minH). Best models included in addition crop N-offtake (U), offtake in unfertilised plots (U(0)), and N(minH) in unfertilised plots (N(minH,0)) and then explained up to 75% of variance. At low N-rates where apparent N recovery rho keeps to its initial value rho(ini), N(minH) keeps to its base level N(minH,0). At N-rates that exceed the value A(crit) where rho drops below rho(ini), N(minH) rises above N(minH,0) by an amount proportional to (rho(ini)-rho)A. About 80% of (rho(ini)-rho)A was found as N(minH,) in grass as well as in maize. The fraction (1-rho(ini))A does not appear to contribute to N(minH) at low N-rates (A< or =A(crit)) or at high N-rates (A>A(crit)).

[A localized reaction to sublingual immunotherapy]. / Een lokale bijwerking van sublinguale immunotherapie.

An otherwise healthy 31-year-old woman with allergic rhinoconjunctivitis developed considerable swelling of the floor of her mouth after sublingual allergen-specific immunotherapy with the hyposensitization product 'Slit One grass pollen'. After discontinuation, complaints disappeared and she was successfully put on a regimen of subcutaneous immunotherapy. Despite a lack of reports of serious adverse reactions in clinical trials, the Inspectorate of Health Care and The Netherlands Pharmacovigilance Centre Lareb received several reports of sometimes serious localized reactions to oral and sublingual allergen-specific immunotherapy. Under-reporting is likely since local reactions are more or less expected. Caution should be exercised with allergen treatment, even in the case of non-invasive administration.

Limits to nitrogen use on grassland.

Data from nitrogen (N) response experiments on grassland in Belgium and the Netherlands were analysed with the help of a descriptive crop N response model, to identify permissible doses below which no accumulation occurs of residual mineral soil N in autumn. N(min). Using different years as separate sets, a total of 29 data sets were obtained from eight locations on various soil types. A large variation was found in N(min) base levels (unfertilised) between locations and between years at a given location. For doses low enough not to affect crop N recovery, every 100 kg N applied was associated with 3-4 kg residual N(min) in autumn. This is considered very low compared to N(min) base levels, but values differed significantly from zero. After normalising N-doses from different sources (mineral fertiliser and cattle slurry) with the help of a coefficient expressing effectiveness based on crop N uptake, no difference was found between fertiliser and slurry in terms of their effect on residual Nmin. The above also holds for nitrate leaching as measured. The sources do differ, however, with respect to long-term effects and these are quantified with a first-order approximation. It it shown that, also after incorporation of long-term effects, much higher N-doses on grassland are justified than the 170 kg N per ha per year in animal manures currently proposed by the European Commission. On normal productive cut grassland as in the analysed experiments, total N doses in cattle slurry up to 400 kg per ha per year have very little effect on residual N(min), if not accompanied by high fertiliser doses. Introducing limits to the use of animal manures on grassland without limiting the input of mineral fertiliser-N lacks any scientific ground.

Meralgia paresthetica is related to degenerative pubic symphysis.

OBJECTIVE: To investigate the relationship between meralgia paresthetica, a mononeuropathy of the lateral femoral cutaneous nerve that often starts in middle age, and radiological degeneration of the pubic symphysis. METHODS: A case-control study of patients aged 40 years and older with meralgia paresthetica who underwent surgical release of the lateral femoral cutaneous nerve; cases were included only when a pelvic radiograph was available. The control group was from a population study including persons aged 55 years and older and was matched to cases (4 controls per case) for sex and age as far as possible. We checked patient records from general practice to ensure control subjects had no symptoms of meralgia paresthetica during the previous 10 years. Radiological degeneration of the pubic symphysis was defined as present when 2 of 3 independent observers noted degeneration on the radiograph. RESULTS: Mantel-Haenszel procedure (stratified for age group and radiological osteoarthritis of the hip) showed a positive relationship (p = 0.004, OR = 4.38) between radiological degenerative pubic symphysis and meralgia paresthetica. In a separate analysis limited to men we also found this positive relationship. CONCLUSION: This study confirmed a positive relationship between radiological degeneration of the pubic symphysis and meralgia paresthetica.

Right temporal lobe glioblastoma presenting in the left orbit. Case report.

Dissemination of gliomas outside the central nervous system without preceding neurosurgery is a rare phenomenon. Glial neoplasms presenting as bone lesions are even more rare. A case of glioblastoma multiforme (GBM) with initial presentation in the orbit following a single generalized seizure is described. Signs of intracranial hypertension resulted from subarachnoid tumor invasion. The patient was treated with whole-dose radiation therapy but survived for only 6 months following the initial presentation. An autopsy revealed a right temporal GBM with extensive subarachnoid spread and invasion in the left orbit and skull base. The literature on dissemination of primary tumors of the brain is reviewed.

Reduced light energy density decreases post-gel contraction while maintaining degree of conversion in composites.

The objective of the study was to evaluate the relationship between curing light intensity and (1) linear post-gel polymerization contraction strain, and (2) degree of conversion of a dental composite. Cylindrical specimens of a dental resin composite were cured from a distance of 7 mm for 40 s at four attenuated light intensities (71%, 49%, and 34% of control intensity and for 20 s at 71% plus 20 s at 100% intensity). A group cured at full intensity served as a control. Degree of conversion (DC) was measured at the top and bottom and linear contraction strain was measured at the bottom of the composite samples. DC at the sample top was significantly different (P < 0.05) between all groups except the 71% and 49% intensity groups. At the sample bottom, DC resulting from the two highest intensities (71% and 100%) were not significantly different from each other (P > 0.05). All other groups were significantly different from each other (P < 0.05). DC for the sample cured at two light intensities was not significantly different from those cured at the lower intensity or higher intensity for 40 s (P > 0.05). The sample cured with two intensities showed a 21.8% reduction from the contraction strain predicted by a light energy density calculation. Application of light at less than the maximum intensity of the curing light resulted in significant reduction of polymerization contraction strain without significantly affecting the degree of conversion.

In vitro aging of dental composites in water--effect of degree of conversion, filler volume, and filler/matrix coupling.

The purpose of this study was to evaluate the long-term effect of aging in water on the physical properties of experimental composites having systematically controlled differences in degree of conversion (DC), filler volume fraction (Vf), and percentage of silane-treated fillers. Composites were made with a 50% Bis-GMA:50% TEGDMA light-cured resin and a 1-2 microm (average size) strontium glass filler (+ 5 wt% SiO2 microfiller). For composites A-E, the DC was varied from 56-66% by changing the curing time; for D and F-I, the Vf was varied from 28-62 vol%; and for D and J-M, the percent of fillers with a silane coupling agent (gamma-MPS) was varied from 20-100%. Fracture toughness (KIc), flexure strength (FS), elastic modulus (E), and hardness (KHN) were tested after soaking in water at 37 degrees C for 1 day, 6 months, 1 year, and 2 years. The KIc was reduced 20-30% for all composites after 6 months, with minimal changes thereafter. The FS was reduced for several composites at 6 months, but only those with poor cure (A and B) were lower at 2 years than they were initially. The E was not reduced for most composites. Hardness was reduced for most composites after 6 months, but many returned to their original levels at 2 years. Long-term aging in water caused a reduction in the KIc, independent of composition, but had little effect on other properties, suggesting limited degradation of composites in water.

The influence of psychological variables on postoperative anxiety and physical complaints in patients undergoing lumbar surgery.

Previous research has indicated that postoperative distress is influenced by diverse biographic, medical and psychological variables, such as personality, coping behaviours and anxiety. The influence of state variables, apart from anxiety and coping behaviour, has received scant attention. Furthermore, the influence of coping behaviour has remained unclear. The present study investigated coping behaviour and indications of physical distress, i.e., preoperative fatigue, leg pain and back pain, besides preoperative anxiety, as predictors of postoperative anxiety and physical complaints in 126 patients undergoing lumbar surgery. Preoperative anxiety and leg pain independently predicted more postoperative anxiety beyond the influence of age, sex and medical variables. Preoperative anxiety and fatigue independently predicted more postoperative physical complaints. No associations were found between the coping behaviours and the postoperative variables. The implications of these results are discussed in relation to intervention strategies aimed at diminishing the stress of surgery.

Fracture toughness of experimental dental composites aged in ethanol.

Fracture toughness (KIc) is an intrinsic property which may be related to the ability of a restorative material to resist fracture and abrasion. This property may change for a dental composite restorative due to the effects of various oral solvents. The hypothesis to be tested was that aging in ethanol would cause a reduction in the fracture toughness of dental composites, and that the extent of this reduction might be dependent upon certain compositional variables. The fracture toughnesses of three series of experimental composites with various degrees of conversion, filler volume, and percent of silane-treated fillers were compared after the composites were aged for periods of one month and six months in 75% ethanol/water, a solvent which serves as a food-simulating liquid. An unfilled Bis-GMA/TEGDMA resin served as the control. All composites, with the exception of one subjected to a post-light-curing heat treatment, experienced a significant reduction (from 30 to 56%) in KIc after being aged in 75% ethanol for six months. A similar reduction in KIc of 58% for the unfilled resin suggested that the reduction for the composites was due to a weakening of the resin matrix, which facilitated crack propagation. A simultaneous reduction in microhardness was also demonstrated. One month of aging in ethanol also produced large reductions in KIc for specimens with insufficient cure and minimal filler volume, suggesting that the properties of the resin matrix predominated for these composites.(ABSTRACT TRUNCATED AT 250 WORDS)

Histological preparation of the undecalcified rat otic bulla for mesoscopic observations.

Otic bullas of the rat, obtained by excision and formalin fixed, are successfully embedded in methylmethacrylate by dehydration and subsequent infiltration with plastic under vacuum. Sections 10 microns thick are obtained by cutting the trimmed and sandpapered acrylic blocks on an LKB multirange microtome. The sections are collected on adhesive tape and stained with a Trichrome stain (modified Weigert-van Gieson). Finally, the sections attached to the tape are mounted on microscope slides with glycerin-gelatin and sealed in the same medium. Serial sections are used for three-dimensional graphic reconstruction.

Electrophysiological aspects of the middle ear muscle reflex in the rat: latency, rise time and effect on sound transmission.

The latency, the rise time and the influence of the acoustic reflex on sound transmission were investigated in the adult rat during ketamin anesthesia. This was done by recordings of the cochlear microphonics (CM) and electromyographic (EMG) recordings of the reflex responses of the tensor tympani muscle. The acoustic reflex was elicited by contralateral acoustic stimuli of which the intensity and frequency was varied. Ipsilaterally, the effect on sound transmission was determined by estimating the change in amplitude of the CM's of ipsilateral administered subliminal stimuli. It was shown that both the tensor tympani muscle and the stapedius muscle contribute in the reflex. The latency as well as the rise time of the reflex determined by CM recordings showed to be short (minimal values: 12 and 7 ms respectively). The mean latency of the tensor tympani muscle reflex, measured by EMG, was about 7 ms. The attenuation of 0.25-8 kHz tone bursts upto 115 dB SPL is limited to a mean maximum of 15 dB SPL. The maximal attenuation was shown to occur at 1 kHz. Frequencies above 2 kHz appeared to be the best elicitor of the middle ear muscle reflex.

Three-dimensional graphic reconstruction of the tympanic bulla of the rat with special reference to the middle ear muscles.

On the basis of functional questions, graphic three-dimensional reconstructions of the tympanic bulla of the rat were made to gain insight into the spatial organisation of the contents of the bulla and especially of the tympanic membrane--ossicular chain--middle ear muscle complex. For this purpose drawings of microscopical sections of complete bullae were fed into the computer to make three-dimensional graphic reconstructions with hidden line removal. From these reconstructions plastic representations were made by the medical artist. The topographical anatomy of the tympanic bulla is discussed in detail and compared to the anatomy of the middle ear in man. It is postulated that, despite differences in spatial organisation of the middle ear of the rat compared to that of man, the middle ear muscles influence the ossicular chain in a comparable way. On the basis of the topographical anatomy it is feasible that the muscles in the rat act synergistically in increasing the stiffness of the ossicular chain.

The innervation of the middle ear muscles of the rat.

The innervation of the tensor tympani muscle and the stapedius muscle in the rat was studied. This was done by acetylcholinesterase in toto staining of the tympanic bullae and of muscles dissected separately, acetylcholinesterase staining of serial cross-sections of the muscles, silver impregnation of serial sections of complete tympanic bullae, serial semithin sections stained according to Laczko & Levai and electron microscopy of both muscles. The gross innervation of the muscles and the relation to other nerves in the bulla are described. It is shown that both muscles are innervated by very thin nerve fibres which form a well-organised elaborate network in the muscles, with very short branches that connect with motor endplates. Electron microscopically there are indications that the endplates in the stapedius muscle seem to enable faster activation of the muscle fibres than those of tensor tympani muscle. No morphological evidence for any sensory innervation of the muscles could be detected in the muscles themselves, in the connective tissue related to the muscles, or in the contents of the bulla tympanica. It is postulated that the afferent input of the acoustic middle ear muscle reflex is sound alone and that sensory information from the muscles themselves or from other structures in the tympanic bulla do not contribute to the reflex.

Detailed morphology of the stapedius muscle of the rat. An integrated light microscopical, morphometrical, histochemical, immunohistochemical and electron microscopical study in relation to function.

The stapedius muscle of the rat, a very small muscle, appeared to have several atypical morphological characteristics. The muscle fibres were found to be irregularly shaped and composed of relatively small bundles of myofibrils. Mitochondria were distributed irregularly, i.e. in long strands, between the bundles of myofibrils. Enzyme histochemically, most fibres could be classified as fast oxidative glycolytic fibres (IIA). Only 5% of the fibres appeared to be slow twitch fibres; however, these fibres also had a high glycolytic capacity and therefore could not be classified as the classical slow twitch fibres. The immunohistochemical staining with monoclonal anti-heavy chain myosin isotypes showed discrepancies when compared to the enzyme histochemical results. Moreover, different adult heavy chain myosin isotypes appeared to coexist in one single muscle fibre. The results suggest that the muscle has an isometric contraction pattern and that it can contract rapidly with great endurance. This endows the muscle with properties suitable for a function in the prevention of noise-induced hearing loss and also in impact noise over longer periods of time.

Detailed morphology of the tensor tympani muscle of the rat. An integrated light microscopical, morphometrical, histochemical, immunohistochemical and electron microscopical study in relation to function.

The gross anatomy, microscopical anatomy, morphometry, enzyme histochemistry, immunohistochemistry and electron microscopy of the tensor tympani muscle of the rat was studied. The aim of the study was to create an integrated insight into the morphology of the muscle and to discuss functional implications. The tensor tympani muscle of the rat is an atypical muscle. It is a small muscle composed of very small muscle fibres with a complex microscopical and submicroscopical architecture. Histochemically the muscle consists mainly of fast oxidative glycolytic fibres, but discrepancies are found when anti-heavy chain myosin antibodies are used for fibre typing. Different adult heavy chain myosin isotypes coexist in one single muscle fibre. The electron microscopical study shows that bundles of myofilaments branch and interconnect with other bundles of myofilaments. The findings suggest that the muscle is able to contract fast and is fatigue-resistant. Both features seem to suggest that the muscle has a function in protecting the inner ear against noise damage.

[Lymphographic and clinical studies following arterial reconstruction in the aortoiliac area and the extremities]. / Lymphographische und klinische Untersuchungen nach arteriellen Rekonstruktionen im aortoiliakalen Abschnitt und im Extremitätenbereich.

Lymphography was carried out in 41 patients after arterial reconstruction in the aorto-iliac territory or in the extremities: 13 of these patients had been examined pre-operatively. In addition to lymphography, the circumference of the limbs was measured. Lymphographic changes and oedema could be demonstrated in all patients, the extent depending on the type of surgical intervention. There was correlation between the extent of lymphatic damage and the oedema. The duration of post operative oedema depended on effective regeneration of the lymphatics; according to the severity of the surgical injury, regeneration was largely complete from 12 weeks to six months after surgery.