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Background Headache is one of the major clinical presentations in pediatric Moyamoya disease. However, the clinical features and underlying mechanisms are not fully understood. This study aimed to clarify the clinical feature of headache in pediatric Moyamoya disease and the effect of surgical revascularization. Methods This study included 29 pediatric patients who underwent superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis and indirect bypass for Moyamoya disease. Their medical records were precisely evaluated to identify the clinical features of their headache. The findings on magnetic resonance imaging, positron emission tomography, and single-photon emission computed tomography also were analyzed. Results Preoperative headache was documented in 11 (38%) of 29 patients. The majority of them complained of severe headache in the frontal or temporal region in the morning. Headache was significantly related to more advanced disease stage and to the decreases in cerebral blood flow and its reactivity to acetazolamide. Surgical revascularization completely resolved headache in all 11 patients. Conclusions These findings strongly suggest that disturbed cerebral hemodynamics may play key roles in developing severe headache in pediatric Moyamoya disease. STA-MCA anastomosis and encephalo-duro-myo-arterio-pericranial synangiosis may be effective procedures to rapidly resolve headache by widely supplying collateral blood flow to the operated hemispheres. more...

Targeting improved spatial resolution, a three-dimensional positron-emission-tomography (PET) scanner employing CdTe semiconductor detectors and using depth-of-interaction (DOI) information was developed, and its physical performance was evaluated. This PET scanner is the first to use semiconductor detectors dedicated to the human brain and head-and-neck region. Imaging performance of the scanner used for 18F -fluorodeoxy glucose (FDG) scans of phantoms and human brains was evaluated. The gantry of the scanner has a 35.0-cm-diameter patient port, the trans-axial field of view (FOV) is 31.0 cm, and the axial FOV is 24.6 cm. The energy resolution averaged over all detector channels and timing resolution were 4.1% and 6.8 ns (each in FWHM), respectively. Spatial resolution measured at the center of FOV was 2.3-mm FWHM-which is one of the best resolutions achieved by human PET scanners. Noise-equivalent count ratio (NEC2R) has a maximum in the energy window of 390 to 540 keV and is 36 kcps/Bq/cm3 at 3.7 kBq/cm3 . The sensitivity of the system according to NEMA 1994 was 25.9 cps/Bq/cm3. Scatter fraction of the scanner is 37% for the energy window of 390 to 540 keV and 23% for 450 to 540 keV. Images of a hot-rod phantom and images of brain glucose metabolism show that the structural accuracy of the images obtained with the semiconductor PET scanner is higher than that possible with a conventional Bismuth Germanium Oxide (BGO) PET scanner. In addition, the developed scanner permits better delineation of the head-and-neck cancer. These results show that the semiconductor PET scanner will play a major role in the upcoming era of personalized medicine. more...

A thermophilic–mesophilic sequence of composting was compared with continuous thermophilic composting in a small-scale laboratory reactor. Dairy cattle manure was allowed to self-heat adiabatically for one week prior to individual temperature treatments at 20, 37, and 55 °C. Preliminary self-heating was carried out to naturally activated indigenous compost microorganisms to attain thermophilic condition. Microbial activity during composting was monitored by measuring oxygen uptake rate (OUR). Total active microbial biomass was measured using the adenosine triphosphate (ATP) bioluminescence technique. Organic matter degradation was determined by measuring the volatile solids content of compost samples. Results showed that composting at 55 °C promotes the rapid degradation of organic matter as shown by high cumulative oxygen uptake. Composting at 37 °C also exhibited high microbial activity probably due to degradation of complex organic compounds. Microbial biomass was found to be high at 20 and 37 °C, indicating larger microbial communities at lower compost temperatures. Organic matter degradation analysis revealed no large differences in the final solid degradation rate at 55 and 37 °C. The study suggests the importance of a thermophilic–mesophilic sequence in composting to maximise the extent of organic matter degradation. more...

Background. Lung resistance increases after induction of anaesthesia. We hypothesized that prophylactic bronchodilation with i.v. carperitide before tracheal intubation would decrease airway resistance and increase lung compliance after placement of the tracheal tube in both smokers and nonsmokers. Methods. Ninety-seven adults aged between 24 and 59 yr were randomized to receive i.v. normal saline (0.9% saline) (control) or carperitide, 0.2 m gk g � 1 min � 1 throughout the study. The 97 patients included smokers and nonsmokers. Thus the patients were allocated to one of the four groups: smokers who received normal saline (n=21), nonsmokers who received normal saline (n=27), smokers who received carperitide (n=19) or nonsmokers who received carperitide (n=30). Thirty minutes after starting normal saline or carperitide infusion, we administered thiamylal 5 mg kg � 1 and fentanyl 5 m gk g � 1 to induce general anaesthesia and vecuronium 0.3 mg kg � 1 for muscle relaxation. Continuous infusion of thiamylal 15 mg kg � 1 h � 1 followed anaesthetic induction. Mean airway resistance (Rawm), expiratory airway resistance (Rawe) and dynamic lung compliance (Cdyn) were determined 4, 8, 12 and 16 min after tracheal intubation and compared between the four groups. Results. At 4 min after intubation, Rawm and Rawe were higher and Cdyn lower in smokers than in nonsmokers in the control group. Rawm and Rawe were lower and Cdyn higher in smokers in the carperitide group than in smokers in the control group. Rawm and Rawe were lower in nonsmokers in the carperitide group than in nonsmokers in the control group. Conclusions. Marked bronchoconstriction occurred in the control groups (smokers and nonsmokers) 4 min after tracheal intubation. Prophylactic treatment with carperitide before induction of anaesthesia and tracheal intubation was advantageous, particularly in smokers. Br J Anaesth 2006; 96: 660–9 more...

A super radiation-resistant motor was developed for ITER, consisting of high radiation-durable organic insulation materials, such as poly(benzimidazole), poly-liquid-crystal (VECRUS/spl reg/, VECTRA/spl reg/), and poly(phenyl ether)/urea grease. The motor was subjected to irradiation tests carried out by /sup 60/Co /spl gamma/-ray at room temperature, and its radiation resistance was confirmed to be more than 100 MGy, which is 50 times of that of an ordinary radiation durable motor. The key factor for attaining high radiation resistance was the application of aluminum (Al) thin leaves (thickness: 0.2 /spl mu/m) mainly having faces. In a /sup 60/Co /spl gamma/-rays irradiation test conducted on VECRUS/spl reg/ paper containing Al leaves and overcoated by a silicon layer, an average absorption cross section for the Compton effect was found to decrease by 20% from the theoretical value calculated by the formula of Klein and Nishina. These results show that a secondary electron beam generated from a /spl gamma/-ray can easily pass through VECRUS/spl reg/ paper coated by a silicon layer including the dispersing Al leaf, by means of the channeling effect through the crystal lattice, thereby avoiding a close single collision and reducing serious damage. more...

A Monte Carlo model of imprisonment of Xe resonant photons and electronic de-excitation of the Xe resonance level, Xe*, in ac colour plasma displays is developed. The number of resonant photons arriving at phosphor are calculated for various discharge cell heights, discharge thicknesses, Xe mixture ratios, current pulse widths, and drive frequencies in 67 kPa Ne+Xe mixtures. From the calculations, it was found that only 23.2% of the total Xe* participate in generating photons, which arrive at the phosphor under a typical electron density of 5.0 × 1019 m−3. Photons from 22.5% Xe* reach the front glass plate where phosphor is not deposited, and 54.3% of Xe* are de-excited by electronic collisions. Driving the discharge cells at low current density is one of the effective methods of reducing the de-excitation loss. Optimized drive conditions, such as a narrow current pulse drive, can suppress the luminous efficiency degradation. An increase in the height of the discharge cell is preferable provided that the discharge fills the space. more...

Objectives: Brain distributions of [123I]iomazenil ([123I]IMZ) and [1-14C]octanoate were compared with CBF and histopathologic findings in a rat model of focal cerebral ischemia, in order to characterize [123I]IMZ and [1-11C]octanoate as markers of neuronal and astroglial functions, respectively. Methods: (1) Brain distributions of [123I]IMZ and [125I]IMP were determined by dual-tracer autoradiography. Microtubule-associated protein-2 (MAP-2) was immunostained. In situ DNA polymerase-I-dependent dUTP incorporation into damaged DNA was used as an indicator of DNA fragmentation. (2) Brain distributions of [1-14C]octanoate and [123I]IMP (or [123I]IMZ) were determined by dual-tracer autoradiography. HE stain was performed to evaluate histologic changes. Results: (1) Neither DNA fragmentation nor MAP-2 denaturation was detected in the ischemic regions with preserved [123I]IMZ accumulation. [123I]IMZ accumulation was significantly impaired in the regions with damaged DNA. (2) Uptake of [1-14C]octanoate and [123I]IMZ was decreased in the peri-infarct regions where necrotic cells were occasionally observed, while [1-14C]octanoate uptake was significantly higher than that of [123I]IMZ in the peri-infarct regions without morphological changes. Conclusion: Impairment of [123I] IMZ accumulation precedes DNA fragmentation. [1-14C]octanoate uptake was relatively preserved in the regions without morphological changes despite the reduced CBF and [123I]IMZ uptake. Our results provide the molecular basis for analyzing neuronal and glial functions with [123I]IMZ and [1-11C]octanoate. more...

Objectives: To shorten the scanning protocol for quantification of cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2), a new method has been developed using 15O-CO2, CO, O2 and PET. Methods: Fifteen patients with carotid occlusion or stenosis were employed. One-minute inhalation of 15O-CO and 3-min static scanning and blood sampling was performed to measure cerebral blood volume (CBV). With 2-min inhalation of 3 GBq 15O-CO2, serial dynamic scanning and arterial blood sampling was performed for 6 min. With 15-min inhalation of 15O-O2, steady state O2 image was scanned for 5 min, and arterial blood and plasma were sampled to measure oxygen extraction fraction (OEF) and CMRO2. In addition, to compare with conventional method, steady state CO2 image was scanned for 5 min with 15-min inhalation of 7.5 GBq 15O-CO2 and arterial blood and plasma sampling. CBF and partition coefficient of water in the brain were estimated by non-linear curve fitting to the tissue time-activity curves. A new method was developed to measure OEF and CMRO2 using the known ratio of arterial H2O and O2 concentration in O2 steady state. The method does not require measuring the plasma counts. For each subject, about 2000 regions of interest (ROIs) were positioned, estimates calculated from a new method (newCBF, newOEF, newCMRO2) were correlated with those from conventional steady state method (ssCBF, ssOEF, ssCMRO2). Results: newCBF, newOEF and newCMRO2 presented significant correlation with those from steady state method, respectively (newCBF (ml/min/100 g)=1.07 ssCBF (ml/min/100 g)+3.17, r=0.934, p more...

A zero-dimensional model of the positive column in Ar/Ne/Xe gas mixtures has been developed to help understand the measured dependence of the efficacy on operating conditions in a mercury-free flat fluorescent lamp in a dielectric barrier geometry. The experimental conditions are such that the radiation from the discharge is homogeneous over most of the discharge voltage. The model uses as input the discharge current waveform from the experiments, and it yields the time variations of the mean electron energy and the species densities. From these quantities we calculate the number of vacuum ultraviolet (VUV) photons emitted by the xenon resonance atoms and excimers during one current pulse and the efficiency for generation of VUV radiation in the positive column, which are compared with the measured luminance and efficacy for various voltages, pulse intervals, and lamp sizes. Over the range of conditions studied, we find that most electrical energy dissipated in xenon excitation is converted to VUV radiation; i.e. the losses of xenon excitation in stepwise and associative ionization processes are small. When the mean electron energy is low, energy dissipation in elastic momentum transfer collisions leads to a decrease in the efficiency. On the other hand, ionization and excitation of argon degrade the efficiency when the mean electron energy is high. To a lesser extent, stepwise excitation of the xenon metastables also decreases the efficiency for high current densities. more...

Background Interictal brain single photon emission computed tomography (SPECT) is useful for the detection of seizure focus. Recent reports indicate a hypoperfusion in the ipsilateral thalamus as a seizure focus on interictal SPECT in temporal lobe epilepsy. In frontal lobe epilepsy (FLE), however, the alteration of perfusion in the thalamus has not been well documented. This study aimed to assess whether perfusion analysis on the thalamus may add useful information for the detection of epileptic foci in patients with FLE. Methods Interictal brain SPECT was performed in 11 patients with FLE. The asymmetry index for the thalamus and frontal area in the SPECT image was calculated in order to compare the laterality of the seizure foci. Results Thalamic asymmetry was seen in seven patients (64%), while cortial asymmetry was seen in six patients (55%). The concordance with the lateralization of the seizure foci was 6/7 (86%) in the thalamus, and 4/6 (67%) in the frontal area. Four patients showed only thalamic asymmetry. Concordance with the lateralization of the seizure focus was found in all of them. Conclusion These preliminary results suggest that hypoperfusion in the thalamus may have a complementary role to lateralize the epileptic foci in patients with FLE. more...

N-acetylchitooligosaccharides, fragments of the backbone of fungal cell wall, trigger rapid membrane responses such as transient depolarization, and elicit defense reactions including phytoalexin production in suspension-cultured rice cells. The generation of reactive oxygen species triggered by the oligosaccharide signal was analyzed with EPR spectroscopy using a spin trapping system, 4-pyridyl 1-oxideN-tert-butyl nitrone (4-POBN) and ethanol. OH generation was detected as the α-hydroxyethyl adduct of 4-POBN after elicitation. Superoxide dismutase, catalase or diethylenetriamine pentaacetic acid, a metal chelator, inhibited $${}^ \cdot O$$ generation, proposing the following reaction sequence: generation of $${}^ \cdot O_{2^ - } $$ in response to the oligosaccharide elicitor, followed by dismutation to H2O2, then generation of $${}^ \cdot OH$$ by the reaction of H2O2 with Fe2+ that is generated by the reduction of Fe3+ by $${}^ \cdot O_{2^ - } $$ . Generation of the same reactive oxygen species was also triggered by calyculin A, a protein phosphatase inhibitor, alone, suggesting the involvement of protein phosphorylation in its regulation during the oligosaccharide signal transduction. more...

The effect of mobile impurity doping on fracture behaviour has been investigated using plasma charging of light elements for Fe-2.5 wt.%Si alloy crystals with particular attention to the role of crack-impurity elastic interactions. FeSi crystals are markedly embrittled by plasma charging of helium as well as hydrogen at around room temperature, this being accompanied by slow crack growth. Neon charging contributes little to the embrittlement, but argon charging does not contribute. The crystals are also embrittled by nitrogen charging in the tests at 450 K and exhibit slow crack growth during the tests. Elastic analyses indicate that crack-impurity interactions are induced not only by the applied KI field but also by the stress modification due to ambient impurities in the presence of a crack. The interactions serve effectively to concentrate mobile impurities ahead of a crack tip, leading to the increase in the local stress intensity kI. The effect of interstitial impurities on crack extension is discussed in connection with the modification of stress states due to impurities around a crack tip. more...

Rheological properties of erythrocytes relate to the oxygen transfer to tissues in microcirculation. Erythrocytes deform by externally applied physical forces. The deformability modifies the pathway of oxygen diffusion inside the microvessel. The rate of oxygen release from flowing erythrocytes in a single microvessel is determined spectrophotometrically under the microscope. more...

We investigated changes in blood flow in normal muscle and in SCC-VII tumors treated by hyperthermia combined with hydralazine, to evaluate the enhancement of thermal tumor damage by hydralazine. We studied SCC-VII tumor-bearing C3H/He mice. Hydralazine was administered by intraperitoneal injection, and tumors were heated by a water bath. We measured blood flow using the laser Doppler method, and oxygen tension using polarography. The response of tumors to therapy was assessed using a growth delay analysis. In tumors, blood flow and O-2 tension significantly decreased with increasing doses of hydralazine. Compared to tumors treated by hydralazine alone or by hyperthermia alone, tumor blood flow was significantly decreased in the group treated by hyperthermia with hydralazine. In tumors treated by hyperthermia with hydralazine, blood flow was significantly decreased with increasing Hyd doses, heat durations, and temperatures. In normal muscle, no decrease in blood flow was induced by hyperthermia, hydralazine, or their combination. In tumors treated by hyperthermia (43 degrees C, 20 min) with hydralazine, a maximum additional growth delay was observed. Our results suggest that a decrease in tumor blood flow caused by hydralazine plays an important role in enhancement of the hyperthermic antitumor effect. more...

Trichlormethiazide was given orally at 1200 hrs or 2400 hrs to rats. Its diuretic effects were greater at 1200 hrs than at 2400 hrs. There were significant correlations between urinary trichlormethiazide and its effects in both trials. The regression lines of two trials did differ. These findings indicate that the effects of trichlormethiazide vary with its administration time. Time-dependent variations in urinary trichlormethiazide and susceptibility to the agent might be involved in this phenomenon. more...

We have previously reported that the responsiveness of blood pressure to nitrendipine, a dihydropyridine calcium antagonist, varies with its time of administration. The present study was undertaken to examine whether the diuretic effects of the agent also show diurnal variation. Nitrendipine was given orally at 12 a.m. or 12 p.m. to rats, and urine was collected for 8 hours after administration. The urine volume and urinary sodium excretion were greater at 12 p.m. than at 12 a.m. These data indicate that the cardiovascular as well as renal effects of nitrendipine vary with its time of administration. more...

Electron field emission has been studied with diamond-like carbon (DLC) films deposited from a liquid phase. The DLC films were deposited on Si substrate by electrolysis of methanol liquid. The field emission measurements were carried out with a parallel plate configuration using the deposited DLC films on Si substrate as a cathode, and an indium tin oxide (ITO) coated glass plate as an anode. We found several bright spots on a luminescent screen mounted on the ITO anode, indicating that the electrons are emitted from the isolated emission sites on the deposited DLC film. The emission current density is more than 10−7 A/cm2 at the electric field as low as 1.2 V/μm. This result suggests that the DLC film deposited from the liquid phase has a potential advantage for field emitter applications. more...

The characteristics of red cell deformation were studied, focusing on deformation response of the cells subjected to oscillatory shear stress. Red blood cells were fractionated into subpopulations of different densities, i.e., low-density and high-density cells. The deformation response of the fractionated cells was evaluated with a rheoscope varying their intracellular viscosity and oscillation frequency of the applied shear stress, and determinants of the deformation response were compared with those of whole cell deformation under stationary shear stress. When the fractionated cells were exposed to sinusoidally oscillated shear stress, the cells underwent oscillatory deformation. The degree of deformation of the low-density cells correspond to the magnitude of the applied shear stress up to an oscillation frequency of 2.7 Hz. Meanwhile, such an oscillatory deformation as to correspond to the applied shear stress was observed up to 1.7 Hz for the high-density cells. It was suggested that intracellular viscosity was an important factor to determine the deformation response of red cells to oscillatory shear stress. more...

Two main subjects of erythrocyte rheology, deformation and aggregation, are discussed in detail, on the basis of biochemical structure. The close relationship between the life span (or cell aging) and the rheology of individual erythrocytes is also briefly described. A currently important problem is emphasized, that is, the molecular aspect of the dynamic cytoskeletal structure and the mechanism of its regulation. This concerns not only the rheological function and the survival of circulating erythrocytes, but also the pathophysiology of abnormal erythrocytes. more...

This study assessed the changes in blood flow volume in elderly hemiplegic patients before and after rehabilitation training. Total hemoglobin accumulation (blood flow volume) was measured using near-infrared spectroscopy (NIRS) in both the affected and unaffected gastrocnemius muscles before and after walking. In the gastrocnemius on the affected side, the blood flow volume was larger during the recovery period than during the rest period, and the blood flow volume did not decrease during the recovery period after the subjects walked a corridor. By contrast, the blood flow volume recovered faster on the unaffected side than on the affected side. After the subjects walked the stairs, the blood flow volume increased in the gastrocnemius muscles on both sides. These results suggested that the level of training involved in walking a corridor was too light for the unaffected side, although it was effective for the affected side. In our subjects, walking the stairs was effective rehabilitation training for both the unaffected and affected sides. Our results suggested that NIRS was an objective tool useful for planning rehabilitation training. more...

Although e-commerce is becoming popular, product rules, which describe various conditions such as prices, applicability, and discount conditions are still expressed in natural languages. These rules are difficult to deal with in relational databases because logics are separated from data. There is no system to search on multiple rules, so buyers have to check business rules one by one. In this paper, we take the case of airline tickets, hotel bookings and others as an example, and describe them in dynamic constraint conditions. We also show several queries written in Dynamic Constraint Algebra (DCA), and the result of the Dynamic Constraint Algebra Query Processing Engine can be utilized to present buyers available options, and to check how variables affect prices. more...

Network communication architecture for cooperative humanoids are designed and realized. The humanoids are operated to walk by two legs. The network is a LAN whose nodes are one master PC and other controller PCs. The master PC works as a central control machine which contains a blackboard, an image processor, and mediators for the controller PCs. The controller PC includes a collaborator and a motion controller. The collaborator communicates with the mediator and the image processor. The motion controller regulates the two-legged humanoid. Under such a combination of computing and communication systems, the walking humanoids carry a bulky box without falling down. The total job is successful if position and angle errors of the humanoids in front of the object are within an admissible range. Thus, this paper successfully adds evidences that walking humanoids can cooperate. The network communications were essential more...

Prenatal stress has long-lasting effects on cognitive function and on the hypothalamic-pituitary-adrenal response to stress. We previously reported that the serotonin concentration and synaptic density in the hippocampus were reduced following prenatal stress [Int J Dev Neurosci 16 (1998) 209]. Since serotonin plays a role in the formation and maintenance of synapses, we hypothesized that a neonatal reduction in hippocampal serotonin levels may lead to learning disabilities in prenatally stressed mice. To test this hypothesis, we treated prenatally stressed mice with a selective serotonin reuptake inhibitor in order to normalize their postnatal serotonin turnover levels. What we found was that the oral administration of a selective serotonin reuptake inhibitor to prenatally stressed mice during postnatal weeks 1-3 but not 6-8 normalized their corticosterone response to stress, serotonin turnover in the hippocampus, and density of dendritic spines and synapses in the hippocampal CA3 region. Concomitantly, such treatment partially restored their ability to learn spatial information. more...

Both the therapeutic and the adverse effects of drugs can be profoundly influenced by the activity of enzymes of drug metabolism. Biotransformation is effected by a number of families of structurally and functionally related enzymes, which inactivate and ultimately enable the excretion of therapeutic agents. The enzymes of drug metabolism exhibit broad and overlapping substrate specificities. Many of these enzymes are now known to exhibit polymorphic expression, due often to point mutations in the structural gene. The result may be a large difference in metabolic activity, and consequently in the pharmacokinetics, between phenotypes. Examples of polymorphic enzymes include CYP2D6, CYP2C9, CYP2C19 and NAT2. Some drug transporters such as ABCB1 (P-glycoprotein) are also polymorphic. The consequences of such polymorphism will depend upon a number of factors, including the steepness of the concentration-effect curve, the contribution of the polymorphic pathway to overall elimination and the magnitude of other sources of variability in the effect of the polymorphic enzyme. In this last case, whilst it might be possible to demonstrate clear differences in effect between phenotypes in healthy volunteers, other sources of variability, including the disease itself, may dominate differences in response in patients. There are some clear examples of the importance of polymorphic drug metabolism in the effects of drugs, such as CYP2C9 and warfarin and NAT2 and hydralazine. However, it is likely that the extent to which genotyping might benefit the individual patient will be established only in adequate clinical studies. more...

BACKGROUND: Magnesium supplementation may reduce the incidence of arrhythmias, which often occur after cardiac surgery; however, recent findings of the effectiveness of magnesium prophylaxis have yielded discrepant results. METHODS: We searched electronic databases for randomized controlled trials of magnesium for the prevention of arrhythmias after cardiac surgery. The primary outcomes comprised the incidence of supraventricular and ventricular arrhythmias, and the secondary outcomes comprised serum magnesium concentration, length of hospital stay, myocardial infarction, and mortality. Effect sizes were estimated using a random-effects model. RESULTS: Seventeen trials (n 2069 patients) met the inclusion criteria. Pooled serum magnesium concentration at 24 hours after surgery in the treatment group was significantly higher than that in the control group (weighted mean difference 0.45 mmol/L [1.1 mg/dL]; 95% confidence interval [CI]: 0.30 to 0.59 mmol/L [0.7 to 1.4 mg/dL]; P 0.001). Magnesium supplementation reduced the risk of supraventricular arrhythmias (relative risk [RR] 0.77; 95% CI: 0.63 to 0.93; P 0.002) and ventricular arrhythmias (RR 0.52; 95% CI: 0.31 to 0.87; P 0.0001), but had no effect on the length of hospital stay (weighted mean difference 0.28 days; 95% CI: 0.70 to 1.27 days; P 0.48), the incidence of perioperative myocardial infarction (RR 1.03; 95% CI: 0.52 to 2.05; P 0.99), or mortality (RR 0.97; 95% CI: 0.43 to 2.20; P 0.94). CONCLUSION: Administration of prophylactic magnesium reduced the risk of supraventricular arrhythmias after cardiac surgery by 23% (atrial fibrillation by 29%) and of ventricular arrhythmias by 48%. Supplementation had no notable benefit with respect to length of hospitalization, incidence of myocardial infarction, or mortality. Am J Med. 2004;117:325–333. ©2004 by Elsevier Inc. more...

Time-dependent changes in lung fields after chest irradiation were analyzed using multidetector-row CT. Routine scans at 3-mm raw thickness and 8-mm recon thickness and precision scans at 0.5-mm raw thickness and 0.5-mm recon thickness were compared with respect to the number of each finding and the time-dependent changes in the rate of each finding. Among the findings visualized by these scans, ground-glass opacity (GGO) showed the highest overall appearance rate. Precision scans exceeded routine scans in the rates of all findings except GGO and confluent shadows, and the two types of scans showed the greatest difference in the rate of GGO. Since we found that GGO tended to be overestimated on routine scans, we confirmed it by a phantom experiment. Precision scans were similar or superior to routine scans in the rates of findings except 3 months after irradiation. We consider that the concomitant use of precision scans is useful in that it allows more accurate evaluation of various post-irradiation changes in lung fields including GGO, in which the lesion is in a reversible stage. more...

Myocardial ischemia is a risk factor during off-pump coronary artery bypass procedures. The development of new regional wall motion abnormalities assessed by transesophageal echocardiography (TEE) is a very sensitive sign of myocardial ischemia. To facilitate anastomosis, the epicardial area of the anastomosis site is often immobilized by a "stabilizer." This study was designed to investigate whether cardiac wall stabilization with an epicardial stabilizer could affect the interpretation of wall motion during coronary anastomosis without cardiopulmonary bypass.The TEE videotapes of 15 adult patients were investigated. Left ventricular (LV) transgastric short and long axis views were divided according to a modified 16-segment method. LV wall motion was scored using a 5-grade scale by two independent blinded investigators during pre-occlusion, occlusion, and reperfusion of anastomosed coronary arteries. The wall motion scores of a stabilized segment combined with two adjacent segments were compared with those of non-stabilized segments. Interobserver agreement was assessed using the weighted kappa statistic.A total of 216 segments were analyzed by two investigators. The interobserver kappa coefficient in pre-occlusion and reperfusion periods was 0.87, 0.87 and 0.86, 0.87, respectively, indicating high agreements without stabilizer. During the occlusion period in stabilized and non-stabilized segments, it was 0.59 and 0.76, respectively, showing significantly less reproducibility in the presence of stabilizer.Cardiac wall stabilization affects the reproducibility in the interpretation of regional wall motion during off-pump coronary artery bypass surgery. Caution should be used when monitoring for myocardial ischemia using TEE during coronary artery bypass surgery with epicardial stabilizer. more...

Determination of the magnitudes of motion-dependent equalizing pulses for reducing the gray scale disturbances on plasma display panels (PDPs) has been examined. First, amounts of light intensity perceived by the retina are calculated. Then the pixels to which to add the equalizing pulses are determined by checking whether the disturbance is dark or bright. Also appropriate sub-fields of each pixel are chosen for emission compensation. Finally, a feedback loop is provided for a fine adjustment of luminance. The technique is applicable to any sub-field configuration. more...

Electroconvulsive therapy (ECT) is commonly associated with acute hyperdynamic cardiovascular responses, and we hypothesize that intravenous lignocaine can blunt this response. We have measured the effect of lignocaine 1.5 mg/kg IV on heart rate and mean arterial pressure during electroconvulsive therapy. Furthermore, we also assessed seizure duration using both the cuff method and two-lead electroencephalography. We studied 25 patients using a randomized, double-blind, placebo-controlled crossover study design. Patients in the control group were given intravenous saline 0.075 ml/kg, and those in the lignocaine group were given intravenous lignocaine 2% 1.5 mg/kg, and this treatment was conducted one minute before intravenous propofol 1.5 mg/kg to induce unconsciousness. Succinylcholine 1.5 mg/kg was then administered intravenously and electrical stimulation was administered after fasciculation. Measurements were taken at the baseline, prior to succinycholine, prior to electroconvulsive therapy and at the peak response after electroconvulsive therapy. Intravenous lignocaine significantly reduced the increases in heart rate after electroconvulsive therapy, as compared with the placebo. The use of intravenous lignocaine was, however, associated with a remarkably shortened seizure duration. Due to the reduction in seizure duration, routine administration of intravenous lignocaine may not be advisable since it may interfere with the psychotherapeutic efficacy of electroconvulsive therapy. However, intravenous lignocaine medication for electroconvulsive therapy is potentially useful for reducing tachycardia in high-risk patients and reducing the severity of propofol injection pain in comparison with a placebo. more...

The inhomogeneity of tissue structure greatly affects the sensitivity of tissue oxygenation measurement by reflectance NIRS. We have proposed a method for correcting the influence of a subcutaneous fat layer on muscle oxygenation measurement. The correction is based on an inverse relationship between the measurement sensitivity and detected light intensity. In this study, this method was validated by measuring the peak-to-peak variation of muscle oxygenation in periodic exercise tests on the vastus lateralis. A multisensor probe consisting of a light source and four photodiodes with source-detector distances of 7-40 mm was newly developed. A proximal detector with a 7-mm separation was used to eliminate the effect of skin. The fat layer thickness was also measured by ultrasonography. Results of the tests clearly showed that the presence of a fat layer greatly decreases the sensitivity of measurement and increases the light intensity at the detectors. Sensitivity correction by detected light intensity resulted in almost the same changes in muscle oxygenation due to periodic exercise among subjects regardless of different fat layer thicknesses. The proximal detector was also effective for reducing the effect of skin. more...