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Pregnancy is characterized by increased bone turnover and reversible loss of bone mineral density (BMD) to meet fetal calcium demands. The long-term effect of bone turnover and maternal diet in pregnancy on maternal bone is not well established.We aimed to determine if an association exists between [1] bone resorption, [2] dietary calcium, and [3] serum 25-hydroxyvitamin D in pregnancy with maternal BMD 5-year postpartum.This is a prospective, longitudinal study of 107 women recruited to the ROLO low glycemic index dietary intervention trial in pregnancy and followed-up at 13, 28, and 34 weeks' gestation and 5 years' postpartum. At 13 and 28 weeks' gestation, a biomarker of bone resorption, urine cross-linked N-telopeptide of type I collagen (uNTX), was measured. At the 5-year follow-up BMD was measured using dual-energy X-ray absorptiometry. Anthropometry, dietary intakes, and serum 25-hydroxyvitamin D were measured in pregnancy and at 5 years. Multiple linear regression, controlling for confounders, was used for analysis.Mean BMD at 5 years was 1.208 g/cmHigher bone resorption and low dietary calcium in pregnancy were associated with lower BMD 5 years later. These findings could enable the identification of women at risk of declining of BMD in later life, but further research is needed. Adequate dietary calcium should be advised in the antenatal setting to promote lifelong maternal bone health.

We describe a unique case of hyperphosphatemia associated with a very high bone turnover rate in a 51-year-old postmenopausal woman with undiagnosed anorexia nervosa (AN) who presented with a low-trauma hip fracture. In view of her severely malnourished state, she was not fit for surgery. She was treated according to a refeeding protocol that mandated bed rest. Contrary to expectation, she developed sustained hyperphosphatemia and borderline hypercalcemia. Bone remodelling markers, both resorption and formation, were markedly elevated. Parathyroid hormone (PTH) was low-normal at 1.7 pmol/L, C-terminal fibroblast growth factor 23 (FGF23) was high at 293 RU/ml, but tubular maximum reabsorption of phosphate (TmPO4/GFR) was elevated at 1.93 mmol/L. Denosumab 60 mg was administered that was followed by: rapid normalisation of serum phosphate; normalisation of resorption markers, transient hypocalcaemia with secondary hyperparathyroidism, and normalisation of both TmPO4/GFR and C-terminal FGF23. We speculate that prolonged immobilization as part of AN management led to a high remodelling state followed by hyperphosphatemia and high-normal calcium with appropriate suppression of PTH and that marked hyperphosphatemia and high TmP/GFR despite high FGF23 indicates the necessity of PTH adequacy for excess FGF23 to lower TmP/GFR.

Physical inactivity is a global health risk that can be addressed through application of exercise training suitable for an individual's health and age. People's willingness to participate in physical activity is often limited by an initially poor physical capability and early onset of fatigue. One factor associated with muscle fatigue during intense contractions is an inexcitability of skeletal muscle cells, reflecting impaired transmembrane Na

British military records provide an unexpected source of information on the lives of ordinary women of the popular classes in the mid-nineteenth-century. This article focuses on the women of the Royal Canadian Rifle Regiment, which served in small garrisons across British North America from 1841 to 1870 and included an unusually large number of families. The increasing regulation of the activities and morals of working-class women was characteristic of this era of middle-class reform. Women’s residence in open barrack rooms with soldiers was a cause of great concern, and led to close monitoring of their behaviour. Abstract: Les archives militaires britanniques constituent une source inattendue de renseignements a propos de la vie de femmes ordinaires des classes populaires au milieu du XIXe siecle. Le present article porte sur les femmes du Royal Canadian Rifle Regiment, qui a ete affecte dans de petites garnisons d’un bout a l’autre de l’Amerique du Nord britannique de 1841 a 1870 et qui comprenait un nombre inhabituellement eleve de familles. La reglementation croissante des activites et de la moralite des femmes de la classe ouvriere etait caracteristique de cette epoque de reforme de la classe moyenne. Le fait que les femmes residaient avec les soldats dans des pieces ouvertes de baraques etait une source de grande inquietude; aussi a-t-il mene a une surveillance etroite de leur comportement.

Guidelines for the prevention of glucocorticoid (GC) induced osteoporosis (GIOP) were implemented in a level 5 Irish Hospital with cross sectional audit of inpatient prescribing undertaken before and after. Prior to guideline implementation, elemental calcium (Ca) with Vitamin D (VitD) was prescribed for 11/66 (17%) of patients on GCs with 2/66 (3%) also receiving bisphosphonate (BP) therapy. Subsequent to guideline implementation, Ca with VitD was prescribed for 19/55 (35%) of patients on GCs with 11/55 (20%) also receiving BP therapy, representing a 2 and 6 fold respective increase. Internal promotion of guidelines is an effective strategy for healthcare improvement but needs refinement with or without repetition to achieve better patient outcomes.

The amount of Ca(2+) stored in the sarcoplasmic reticulum (SR) of muscle fibres is decreased in aged individuals, and an important question is whether this results from increased Ca(2+) leakage out through the Ca(2+) release channels (ryanodine receptors; RyRs). The present study examined the effects of blocking the RyRs with Mg(2+), or applying a strong reducing treatment, on net Ca(2+) accumulation by the SR in skinned muscle fibres from Old (∼70 years) and Young (∼24 years) adults. Raising cytoplasmic [Mg(2+)] and reducing treatment increased net SR Ca(2+) accumulation in type I fibres of Old subjects relative to that in Young. The densities of RyRs and dihydropyridine receptors were not significantly changed in the muscle of Old subjects. These findings indicate that oxidative modification of the RyRs causes increased Ca(2+) leakage from the SR in muscle fibres in Old subjects, which probably deleteriously affects normal muscle function both directly and indirectly.The present study examined whether the lower Ca(2+) storage levels in the sarcoplasmic reticulum (SR) in vastus lateralis muscle fibres in Old (70 ± 4 years) relative to Young (24 ± 4 years) human subjects is the result of increased leakage of Ca(2+) out of the SR through the Ca(2+) release channels/ryanodine receptors (RyRs) and due to oxidative modification of the RyRs. SR Ca(2+) accumulation in mechanically skinned muscle fibres was examined in the presence of 1, 3 or 10 mm cytoplasmic Mg(2+) because raising [Mg(2+)] strongly inhibits Ca(2+) efflux through the RyRs. In type I fibres of Old subjects, SR Ca(2+) accumulation in the presence of 1 mm Mg(2+) approached saturation at shorter loading times than in Young subjects, consistent with Ca(2+) leakage limiting net uptake, and raising [Mg(2+)] to 10 mm in such fibres increased maximal SR Ca(2+) accumulation. No significant differences were seen in type II fibres. Treatment with dithiothreitol (10 mm for 5 min), a strong reducing agent, also increased maximal SR Ca(2+) accumulation at 1 mm Mg(2+) in type I fibres of Old subjects but not in other fibres. The densities of dihydropyridine receptors and RyRs were not significantly different in muscles of Old relative to Young subjects. These findings indicate that Ca(2+) leakage from the SR is increased in type I fibres in Old subjects by reversible oxidative modification of the RyRs; this increased SR Ca(2+) leak is expected to have both direct and indirect deleterious effects on Ca(2+) movements and muscle function.

A capacitively coupled interdigital probe technique is described whereby the electrical characteristics of thin films at arbitrary frequencies in the range from about 100 kHz to beyond 1 GHz may be studied. Patterning of the film, deposition of electrodes, and bonding of electrical leads are unnecessary, so that all measurements are nondestructive and noninvasive. Preliminary measurements of the superconducting transition in thin films of the high-temperature superconductor YBa2Cu3O7−δ in magnetic fields up to 1.5 T are presented and discussed. They show a large field-dependent peak, attributable to tunneling effects, just below the onset temperature. Anomalies are also seen at higher temperatures, providing evidence of a structural phase transition.

Calcium cycling is integral to muscle performance during the rapid muscle contraction and relaxation of high-intensity exercise. Ca(2+) handling is altered by diabetes mellitus, but has not previously been investigated in human skeletal muscle. We investigated effects of high-intensity exercise and sprint training on skeletal muscle Ca(2+) regulation among men and women with type 1 diabetes (T1D, n = 8, 3F, 5M) and matched non-diabetic controls (CON, n = 8, 3F, 5M). Secondarily, we examined sex differences in Ca(2+) regulation. Subjects undertook 7 weeks of three times-weekly cycle sprint training. Before and after training, performance was measured, and blood and muscle were sampled at rest and after high-intensity exercise. In T1D, higher Ca(2+)-ATPase activity (+28%) and Ca(2+) uptake (+21%) than in CON were evident across both times and days (P0.05), but performance was similar. In T1D, resting Ca(2+)-ATPase activity correlated with work performed until exhaustion (r = 0.7, P0.01). Ca(2+)-ATPase activity, but not Ca(2+) uptake, was lower (-24%, P0.05) among the women across both times and days. Intense exercise did not alter Ca(2+)-ATPase activity in T1D or CON. However, sex differences were evident: Ca(2+)-ATPase was reduced with exercise among men but increased among women across both days (time × sex interaction, P0.05). Sprint training reduced Ca(2+)-ATPase (-8%, P0.05), but not Ca(2+) uptake, in T1D and CON. In summary, skeletal muscle Ca(2+) resequestration capacity was increased in T1D, but performance was not greater than CON. Sprint training reduced Ca(2+)-ATPase in T1D and CON. Sex differences in Ca(2+)-ATPase activity were evident and may be linked with fibre type proportion differences.

For thin film metalorganic chemical vapor deposition (MOCVD), a stoichiometric gas phase can be obtained from a mixture of the precursors in the desired mole ratios, in spite of differences in the volatilities of the individual compounds. Proper film composition is obtained by controlling the velocity of a carriage containing the precursors through the heating zone of a vaporizer. YBaCuO (YBCO) superconducting films were prepared on yttrium stabilized zirconia (YSZ) (001) crystal substrates by single source MOCVD using a mixture of powders of Y(thd)/sub 3/, Ba(thd)/sub 2/ and Cu(thd)/sub 2/ as sources. Nondestructive measurements of resistivity, critical current, composition, and surface morphology were performed on these films. A single crystal film with T/sub co/=89 K was made under optimum conditions. Its homogeneity was investigated by resistivity and T/sub co/ measurements and by atomic force microscopy (AFM) at several points of the surface along a diameter of this film. The roughness of the film is higher at the edge than at the center, and this appears to be correlated with the normal state resistivity. The c-axis and a-axis YBCO phases compete with each other at substrate temperatures ranging from 750 to 820/spl deg/C. The c-axis YBCO phase shows spiral growth structure and the spiral step height is about 12.

Oxidation can decrease or increase the Ca2+ sensitivity of the contractile apparatus in rodent fast-twitch (type II) skeletal muscle fibres, but the reactions and molecular targets involved are unknown. This study examined whether increased Ca2+ sensitivity is due to S-glutathionylation of particular cysteine residues. Skinned muscle fibres were directly activated in heavily buffered Ca2+ solutions to assess contractile apparatus Ca2+ sensitivity. Rat type II fibres were subjected to S-glutathionylation by successive treatments with 2,2′-dithiodipyridine (DTDP) and glutathione (GSH), and displayed a maximal increase in pCa50 (−log10 [Ca2+] at half-maximal force) of ∼0.24 pCa units, with little or no effect on maximum force or Hill coefficient. Partial similar effect was produced by exposure to oxidized gluthathione (GSSG, 10 mM) for 10 min at pH 7.1, and near-maximal effect by GSSG treatment at pH 8.5. None of these treatments significantly altered Ca2+ sensitivity in rat type I fibres. Western blotting showed that both the DTDP–GSH and GSSG–pH 8.5 treatments caused marked S-glutathionylation of the fast troponin I isoform (TnI(f)) present in type II fibres, but not of troponin C (TnC) or myosin light chain 2. Both the increased Ca2+ sensitivity and glutathionylation of TnI(f) were blocked by N-ethylmaleimide (NEM). S-nitrosoglutathione (GSNO) also increased Ca2+ sensitivity, but only in conditions where it caused S-glutathionylation of TnI(f). In human type II fibres from vastus lateralis muscle, DTDP–GSH treatment also caused similar increased Ca2+ sensitivity and S-glutathionylation of TnI(f). When the slow isoform of TnI in type I fibres of rat was partially substituted (∼30%) with TnI(f), DTDP–GSH treatment caused a significant increase in Ca2+ sensitivity (∼0.08 pCa units). TnIf in type II fibres from toad and chicken muscle lack Cys133 present in mammalian TnIf, and such fibres showed no change in Ca2+ sensitivity with DTDP–GSH nor any S-glutathionylation of TnI(f) (latter examined only in toad). Following 40 min of cycling exercise in human subjects (at ∼60% peak oxygen consumption), TnI(f) in vastus lateralis muscle displayed a marked increase in S-glutathionylation (∼4-fold). These findings show that S-glutathionylation of TnI(f), most probably at Cys133, increases the Ca2+ sensitivity of the contractile apparatus, and that this occurs in exercising humans, with likely beneficial effects on performance.

There is considerable interest in potential ergogenic and therapeutic effects of increasing skeletal muscle carnosine content, although its effects on excitation-contraction (EC) coupling in human muscle have not been defined. Consequently, we sought to characterize what effects carnosine, at levels attained by supplementation, has on human muscle fiber function, using a preparation with all key EC coupling proteins in their in situ positions. Fiber segments, obtained from vastus lateralis muscle of human subjects by needle biopsy, were mechanically skinned, and their Ca(2+) release and contractile apparatus properties were characterized. Ca(2+) sensitivity of the contractile apparatus was significantly increased by 8 and 16 mM carnosine (increase in pCa(50) of 0.073 ± 0.007 and 0.116 ± 0.006 pCa units, respectively, in six type I fibers, and 0.063 ± 0.018 and 0.103 ± 0.013 pCa units, respectively, in five type II fibers). Caffeine-induced force responses were potentiated by 8 mM carnosine in both type I and II fibers, with the potentiation in type II fibers being entirely explicable by the increase in Ca(2+) sensitivity of the contractile apparatus caused by carnosine. However, the potentiation of caffeine-induced responses caused by carnosine in type I fibers was beyond that expected from the associated increase in Ca(2+) sensitivity of the contractile apparatus and suggestive of increased Ca(2+)-induced Ca(2+) release. Thus increasing muscle carnosine content likely confers benefits to muscle performance in both fiber types by increasing the Ca(2+) sensitivity of the contractile apparatus and possibly also by aiding Ca(2+) release in type I fibers, helping to lessen or slow the decline in muscle performance during fatiguing stimulation.

Production of reactive oxygen species (ROS) in skeletal muscle is markedly increased during exercise and may be essential for exercise adaptation. We, therefore, investigated the effects of infusion with the antioxidant N-acetylcysteine (NAC) on exercise-induced activation of signalling pathways and genes involved in exercise adaptation in human skeletal muscle.Subjects completed two exercise tests, 7 days apart, with saline (control, CON) or NAC infusion before and during exercise. Exercise tests comprised of cycling at 71% VO(2peak) for 45 min, and then 92% VO(2peak) to fatigue, with vastus lateralis biopsies at pre-infusion, after 45-min cycling and at fatigue.Analysis was conducted on the mitogen-activated protein kinase signalling pathways, demonstrating that NAC infusion blocked the exercise-induced increase in JNK phosphorylation, but not ERK1/2, or p38 MAPK. Nuclear factor-κB p65 phosphorylation was unaffected by exercise; however, it was reduced in NAC at fatigue by 14% (P0.05) compared with pre-infusion. Analysis of exercise and/or ROS-sensitive genes demonstrated that exercise-induced mRNA expression is ROS dependent of MnSOD, but not PGC-1α, interleukin-6, monocyte chemotactic protein-1, or heat-shock protein 70.These results suggest that inhibition of ROS attenuates some skeletal muscle cell signalling pathways and gene expression involved in adaptations to exercise.

We observed novel ultrasonic absorption peaks in helimagnetic and Ferro-I phases of gadolinium alloys. These peaks occur only for longitudinal waves propagating along the direction of spontaneous spin ordering, in the presence of an external thus indicating the existence of a novel spin-phonon coupling mechanism, not predicted by conventional models of spin-phonon interactions.

We have made meaurements of the layer-by-layer growth of solid 4 He from the superfluid onto a graphite substrate, and at temperatures below 0.95 K and up to eight layers we have observed remarkable and unexpected behavior which gives clear evidence of a two-stage layering transition. It is speculated that the two stages may result from the different binding energies at step and kink sites (possibly involving quantum kinks) or an incommensurate-commensurate transition

Investigations of many quantum and solid-state systems of interest require measurements on samples that are either very fragile, as in the aerogel- 4 He system, very small, such as samples of high-Tc materials, or both small and fragile, such as a single grain quasicrystal. Many relevant properties of these systems can be deduced from sound-velocity measurements; we present here some techniques for making such measurements, using acoustic resonators and novel transduction mechanisms. The use of acoustic resonance, as opposed to pulses, for measuring sound velocity permits relatively low frequencies to be used; in addition, frequency becomes the primary quantity of interest, which can be measured with ease and precision.

In this paper, a new photoacoustic technique is described for measuring very low optical absorption in crystals and glasses. The technique differs from the conventional photoacoustic technique in that it does not use a high‐power laser pulse to excite an acoustic signal in the sample, but instead uses a continuous laser with the beam modulated at an acoustic resonance frequency of the sample. By exciting the sample at resonance, the acoustic signal is enhanced by a factor proportional to the quality factor (Q) of the resonance. Because highly transparent crystals and glasses may have a Q on the order of 104 to 106, the technique is orders of magnitude more sensitive than conventional techniques. The Q is enhanced through the use of noncontact acoustic transducers, which also eliminate the problem of background signals due to scattered light. Measurements with various quartz samples have been used to verify the technique. Using a 10‐W continuous laser, the noise level of the resonant photoacoustic techniqu...

Superfluid $^{4}\mathrm{He}$ is interesting acoustically because it can support more than one mode of sound propagation, and these can be used to study critical properties. Recently, there has been interest in superfluid-filled aerogels, but for such compressible materials one does not observe the ordinary (fourth) sound; instead there is a mode intermediate between first and fourth sound and a second-sound-like mode. We present a theory for the modes and the first observation of the aerogel second-sound-like mode, which is important because it propagates near the critical temperature.

Exercise increases Na(+)-K(+) pump isoform gene expression and elevates muscle reactive oxygen species (ROS). We investigated whether enhanced ROS scavenging induced with the antioxidant N-acetylcysteine (NAC) blunted the increase in Na(+)-K(+) pump mRNA during repeated contractions in human and rat muscle. In experiment 1, well-trained subjects received saline or NAC intravenously prior to and during 45 min cycling. Vastus lateralis muscle biopsies were taken pre-infusion and following exercise. In experiment 2, isolated rat extensor digitorum longus muscles were pre-incubated without or with 10 mm NAC and then rested or stimulated electrically at 60 Hz for 90 s. After 3 h recovery, muscles were frozen. In both experiments, the muscles were analysed for Na(+)-K(+) pump alpha(1), alpha(2), alpha(3), beta(1), beta(2) and beta(3) mRNA. In experiment 1, exercise increased alpha(2) mRNA by 1.0-fold (P = 0.03), but alpha(2) mRNA was reduced by 0.40-fold with NAC (P = 0.03). Exercise increased alpha(3), beta(1) and beta(2) mRNA by 2.0- to 3.4-fold (P0.05), but these were not affected by NAC (P0.32). Neither exercise nor NAC altered alpha(1) or beta(3) mRNA (P0.31). In experiment 2, electrical stimulation increased alpha(1), alpha(2) and alpha(3) mRNA by 2.3- to 17.4-fold (P0.05), but these changes were abolished by NAC (P0.07). Electrical stimulation almost completely reduced beta(1) mRNA but only in the presence of NAC (P0.01). Neither electrical stimulation nor NAC altered beta(2) or beta(3) mRNA (P0.09). In conclusion, NAC attenuated the increase in Na(+)-K(+) pump alpha(2) mRNA with exercise in human muscle and all alpha isoforms with electrical stimulation in rat muscle. This indicates a regulatory role for ROS in Na(+)-K(+) pump alpha isoform mRNA in mammalian muscle during repeated contractions.

We aimed to examine the differences between patients with cystic fibrosis-related diabetes (CFRD), and those with normal glucose handling in adults with cystic fibrosis (CF) in Ireland. We conducted a retrospective analysis of patients who attend the national referral centre for adult CF. Patients were diagnosed as having CFRD by the American Cystic Fibrosis Foundation criteria for diagnosis of CFRD. Of 259 patients, 150 were classifiable and 81 (54%) were classified as having CFRD. The groups with and without CFRD were not significantly different with regard to age (median 28.4 vs 26.0 years), sex (males 56% vs 55%) or BMI (median 20.9 vs 21.3 kg/m2). The group with CFRD had poorer lung function (mean % predicted FEV1 49.9 vs 66.4, P0.001), poorer bone mineral density (T-scores at the lumbar spine -1.95 vs -1.44, P0.05 and femur -1.19 vs -0.57, P0.01) and a greater proportion of PSEUDOMONAS AERUGINOSA positive sputum cultures (82.5% vs 64.2%, P0.05). No patients with CFRD carried the R1 17H mutation whilst 19% of the group without CFRD were heterozygous for this defect (P0.001). In conclusion, CFRD was highly prevalent in adults. The presence of CFRD was associated with poorer lung function, poorer bone mineral density and an increased prevalence of PSEUDOMONAS AERUGINOSA in sputum. The R1 17H mutation may be protective for CFRD.

The detection of concealed weapons at a distance is a critical security issue that has been a great challenge for different imaging approaches. In this paper, we discuss the use of ultrasonics in a novel way to probe for metallic and nonmetallic materials under clothing. Conventional ultrasonics has problems penetrating clothing and produces false positives from specular reflections. Our approach is to use ultrasonics to create a localized zone where nonlinear interactions generate a lower frequency acoustic wave that is able to penetrate clothing better than direct ultrasonics. The generation of a probing beam for concealed weapons is described in this brief summary showing comparisons of the physical models with the experimental data. An imaging scan of concealed improvised weapons seized by officials at corrections institutes is presented to highlight the value of this approach

Surface acoustic wave (SAW) velocity and attenuation measurements have been performed on high-temperature superconducting YBa2Cu3O7−δ (YBCO) thin films (deposited on nonpiezoelectric substrates), and YBCO single crystals. A “bridge” technique is employed in which piezoelectric substrates, patterned with interdigital transducers, are bonded to the sample under investigation. The temperature dependence of 168 MHz SAW attenuation in a single crystal near its superconducting transition has been measured in applied magnetic fields up to 1.6 T. Features are seen above the superconducting transition temperature which may be indicative of a transition in the electric polarization of the material. A field-dependent attenuation peak, seen in the superconducting state, is discussed in terms of the theory of thermally activated vortex motion.

Characterization of expression of, and consequently also the acute exercise effects on, Na(+),K(+)-ATPase isoforms in human skeletal muscle remains incomplete and was therefore investigated. Fifteen healthy subjects (eight males, seven females) performed fatiguing, knee extensor exercise at approximately 40% of their maximal work output per contraction. A vastus lateralis muscle biopsy was taken at rest, fatigue and 3 and 24 h postexercise, and analysed for Na(+),K(+)-ATPase alpha(1), alpha(2), alpha(3), beta(1), beta(2) and beta(3) mRNA and crude homogenate protein expression, using Real-Time RT-PCR and immunoblotting, respectively. Each individual expressed gene transcripts and protein bands for each Na(+),K(+)-ATPase isoform. Each isoform was also expressed in a primary human skeletal muscle cell culture. Intense exercise (352 +/- 69 s; mean +/-s.e.m.) immediately increased alpha(3) and beta(2) mRNA by 2.4- and 1.7-fold, respectively (P0.05), whilst alpha(1) and alpha(2) mRNA were increased by 2.5- and 3.5-fold at 24 h and 3 h postexercise, respectively (P0.05). No significant change occurred for beta(1) and beta(3) mRNA, reflecting variable time-dependent responses. When the average postexercise value was contrasted to rest, mRNA increased for alpha(1), alpha(2), alpha(3), beta(1), beta(2) and beta(3) isoforms, by 1.4-, 2.2-, 1.4-, 1.1-, 1.0- and 1.0-fold, respectively (P0.05). However, exercise did not alter the protein abundance of the alpha(1)-alpha(3) and beta(1)-beta(3) isoforms. Thus, human skeletal muscle expresses each of the Na(+),K(+)-ATPase alpha(1), alpha(2), alpha(3), beta(1), beta(2) and beta(3) isoforms, evidenced at both transcription and protein levels. Whilst brief exercise increased Na(+),K(+)-ATPase isoform mRNA expression, there was no effect on isoform protein expression, suggesting that the exercise challenge was insufficient for muscle Na(+),K(+)-ATPase up-regulation.

A technique was developed which allows for surface acoustic wave (SAW) experiments up to 500 MHz in YBCO single crystals and films on piezoelectric as well as non-piezoelectric substrates. Experimental data on a granular YBCO film show a field dependent attenuation peak below T/sub c/ which is indicative of temperature dependent changes of the coupling of the magnetic vortex system to the crystal lattice and might be related to melting or depinning of the vortex lattice.

Ultrasonic attenuation and sound velocity were measured at frequencies ranging from 25 MHz to 305 MHz in a large single crystal of La/sub 2-x/Sr/sub x/CuO/sub 4/ with nominal x of about 0.15. The observed features in attenuation and velocity suggest a relaxation process of magnetic origin at about 27 K, and those at /spl sim/37.9 K originate in the superconducting transition and a possible structural instability slightly above it.

According to a radiograph survey in 1982, Paget's disease of bone is common in Ireland but, to date, there have been no clinical reports. In a survey of 24 patients with Paget's disease of bone, we found monostotic disease in 8 and polyostotic disease in 16. Complications were common including deformity (21%), fracture (17%) and deafness (8%). Bisphosphonate therapy induced a remission in 22 patients.

This study investigated whether hypoxic exposure increased muscle buffer capacity (beta(m)) and mechanical efficiency during exercise in male athletes. A control (CON, n=7) and a live high:train low group (LHTL, n=6) trained at near sea level (600 m), with the LHTL group sleeping for 23 nights in simulated moderate altitude (3000 m). Whole body oxygen consumption (VO2) was measured under normoxia before, during and after 23 nights of sleeping in hypoxia, during cycle ergometry comprising 4 x 4-min submaximal stages, 2-min at 5.6 +/- 0.4 W kg(-1), and 2-min 'all-out' to determine total work and VO(2peak). A vastus lateralis muscle biopsy was taken at rest and after a standardized 2-min 5.6 +/- 0.4 W kg(-1) bout, before and after LHTL, and analysed for beta(m) and metabolites. After LHTL, beta(m) was increased (18%, P0.05). Although work was maintained, VO(2peak) fell after LHTL (7%, P0.05). Submaximal VO2 was reduced (4.4%, P0.05) and efficiency improved (0.8%, P0.05) after LHTL probably because of a shift in fuel utilization. This is the first study to show that hypoxic exposure, per se, increases muscle buffer capacity. Further, reduced VO2 during normoxic exercise after LHTL suggests that improved exercise efficiency is a fundamental adaptation to LHTL.

To develop and validate a patient-based instrument to measure both facial impairment and disability, the Facial Clinimetric Evaluation (FaCE) Scale.Prospective instrument validation.Eighty-six patients with a documented history of facial paralysis completed a preliminary, 51-item instrument (alpha FaCE Scale), as well as the previously developed Facial Disability Index (FDI) and the Medical Outcomes Study Short Form 36 Item Questionnaire (SF-36). Two weeks after completing these instruments, 76 patients again completed the alpha FaCE Scale. Forty-one of the patients were also evaluated using the House-Brackmann Grading System (HBGS) and the Facial Grading System (FGS).Exploratory principal component factor analysis grouped 15 FaCE Scale items into 6 impairment and disability categories (domains), forming the beta FaCE Scale. Overall, the test-retest reliability of the FaCE Scale was high (Spearman's correlation coefficient (r) = 0.88, P.01), as were the reliability coefficients of the individual domains (r = 0.81-0.92, P.01). The FaCE Scale domains showed appropriate correlation to global visual analogue scale questions posed on the original alpha FaCE Scale (r = 0.65-0.81, P.01). Overall, the FaCE Scale showed significant correlation with HBGS and FGS scores (r = -0.55 and 0.57, respectively; P.01). However, not all FaCE Scale domains correlated with the HBGS and FGS scores.A reliable and valid patient-based system to measure impairment and disability in facial paralysis has been developed. This system appears to be better than traditional, physician-graded scales for evaluating quality-of-life issues affected by facial disability.

To determine if angiogenic growth factors including vascular endothelial growth factor (VEGF) and platelet-derived endothelial cell growth factor (PD-ECGF) are expressed in human paragangliomas.A histopathologic and molecular examination of paraganglioma specimens obtained from surgical cases or retrieved from the Pathology Department of the Massachusetts Eye and Ear Infirmary.Fresh tumor or archival, paraffin-embedded paraganglioma specimens were analyzed by immunohistochemistry, Western blotting, and ELISA.Positive immunohistochemical staining for VEGF was observed in five of nine surgical specimens and in six of eight archival specimens (11/17, or 65%). PD-ECGF immunoreactivity was detected in four of five surgical specimens and six of eight archival specimens (10/13, or 77%). The presence of PD-ECGF was confirmed by Western blot assay and ELISA confirmed the presence of VEGF in tumor extract.Both VEGF and PD-ECGF are expressed in paragangliomas and may contribute to the extreme vascularity of these tumors. Key Words. Vascular endothelial growth factor, platelet-derived, endothelial cell growth factor, hypoxia, tumor vasculature.

The use of antibiotics before and after surgery has made infectious complications of neurotologic surgery rare. The neurosurgical literature cites a rate of postoperative meningitis between 1% and 2% for "clean" cases and 1.5% to 2.5% for "clean contaminated" cases, such as cerebrospinal fluid contact with the middle ear or mastoid. Reports of infections after neurotologic procedures are rare in the otologic literature. In this report, two patients with brain abscess occurring in a delayed fashion after surgery are described.The study design was a retrospective chart review and case report.The study was conducted at a tertiary referral center.Patient 1 underwent a suboccipital craniotomy for removal of an acoustic neuroma and had an uneventful postoperative recovery. Three months after surgery, he reported mild unsteadiness. Examination revealed mild ataxia, which led to repeat magnetic resonance imaging (MRI) and a diagnosis of cerebellar abscess. Patient 2 underwent translabyrinthine removal of an acoustic neuroma complicated by postoperative Pseudomonas aeruginosa meningitis, which responded promptly to intravenous antibiotics. Fifteen months after surgery, he visited a neurologist after having a seizure and was treated with anticonvulsants. After a second episode of seizure, imaging studies showed a temporal lobe abscess.The signs of intracranial abscess may be subtle and can occur weeks or months after surgery, requiring vigilance and a high index of suspicion for diagnosis. A change in postoperative symptoms after acoustic neuroma surgery should signal further investigation using MRI with gadolinium.

Otosclerosis does not occur outside the temporal bone.The widely accepted assumption that otosclerosis is confined to the temporal bone has never been tested. It is important to investigate this issue, particularly because of evidence that otosclerosis may be a systemic (genetic) disease that could affect other bones.Biopsies from 9 to 11 skeletal sites were obtained from 2 patients with clinical otosclerosis. Two hundred forty-one nontemporal bone sections were examined by light microscopy.No nontemporal skeletal bone section showed histologic evidence of otosclerosis. The data indicate, with 95% confidence, that the true prevalence of otosclerosis in the extratemporal skeleton of the 2 patients examined was3%.These findings suggest that otosclerosis is unlikely to occur outside the temporal bone. Factors unique to the otic capsule that may predispose it to otosclerosis are lack of bone remodeling and the presence of globuli interossei.

Staining for mast cells in undecalcified sections of bone was evaluated with a variety of toluidine blue (TB) preparations. Attention was given to color change in granules, nuclear clarity, background staining, and appearance of bone. Our buffered TB stain, which was developed to highlight bone detail, resulted in violaceous staining of the granules in mast cells, often restricting their identification. An acidified TB stain and a new stain of TB dissolved in 30% ethanol resulted in purple granules. Prestaining with Congo red prior to acidified TB allowed good bone detail and full expression of metachromasia with red appearance of the granules, giving the best view of the mast cell. (The J Histotechnol 13: 49, 1990)

Otosclerosis is related to mild osteogenesis imperfecta with genetic defects in type I collagen.Otosclerosis is a common bone disease of the human otic capsule that has an underlying hereditary predisposition. The histopathology and clinical manifestations are strikingly similar to the milder forms of osteogenesis imperfecta in which mutations of type I collagen genes have been established as the underlying cause.The authors investigated the genetic basis of otosclerosis by conducting an association study using polymorphic DNA markers from patients with clinical otosclerosis and random control subjects.This study showed a significant association between clinical otosclerosis and the type I collagen COL1A1 gene using three different polymorphic markers within the gene.Some cases of clinical otosclerosis may be related to mutations within the COL1A1 gene that are similar to those found in mild forms of osteogenesis imperfecta and result in null expression of the mutant allele.

Investigation of a possible viral etiology for otosclerosis was initiated because of the clinical and histopathologic similarities between otosclerosis and Paget's disease of bone and the mounting evidence of a viral etiology in Paget's disease. Thus far, ultrastructural and immunohistochemical studies have revealed measles-like structures and antigens in active otosclerotic lesions. A method for isolation and identification of both DNA and RNA sequences in archival human temporal bone specimens using the polymerase chain reaction technique has been developed. With use of this technique, a 115-base pair sequence of the measles nucleocapsid gene has been identified in 8 of 11 different temporal bone specimens with histologic evidence of otosclerosis. Zero of nine control specimens without histologic evidence of otosclerosis were positive. The association between the presence of the measles nucleocapsid gene sequence and histologic otosclerosis was significant (p0.01). This study provides further evidence for a possible measles virus etiology in otosclerosis.

The subtemporal transpetrous approach to the petroclival region uses a combination of techniques, including a petrosectomy and a subtemporal and suboccipital craniotomy. Ligation of the greater petrosal sinus, sigmoid sinus, and retraction of the temporal lobe affords wide exposure to the petroclival region and ventral brainstem and minimizes the need for facial nerve translocation. This approach has been successfully used in the management of 10 large tumors of the region, including chondrosarcomas, chordomas, meningiomas, and schwannomas. The history and evolution of this technique and its relation to other similar approaches is discussed.

Patients with satisfactory facial nerve function [House-Brackmann (HB) grade I or II] immediately after acoustic neuroma surgery are at risk for delayed facial paralysis. To study this problem, 255 consecutive patients who underwent acoustic neuroma excision with facial nerve preservation were identified. Delayed facial paralysis occurred in 62 (24.3%) patients; 90% ultimately recovered to their initial postoperative HB grade, and 98.3% recovered to within one grade of their initial HB level. Paralysis occurred at an average of 3.65 postoperative days (range, 1-16 days). The average time to maximal recovery for those with changes of 1, 2, 3, and 4 HB grades was 5.6, 21.5, 39.8, and 50.5 weeks, respectively. The early onset of paralysis (48 h after surgery) resulted in shorter average recovery times. Of patients who demonstrated nerve deterioration to grades IV-VI, 20 of 38 required tarsorrhaphy or gold-weight placement. We conclude that the over-whelming majority of patients with delayed facial paralysis after acoustic neuroma surgery do eventually recover to their postoperative HB grade. The magnitude and timecourse of delayed facial paralysis are predictive factors for subsequent recovery.