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Stent grafts (SG) and drug eluting stents (DES) have emerged to combat intimal hyperplasia. It remains unclear which type of stent yields superior outcomes in femoropopliteal (FP) arterial lesions. This study compared the clinical data between the VIABAHN SG and the Eluvia DES two years after endovascular treatment.In this retrospective multicentre study, 504 cases with a lesion length10 cm treated either with SG or DES were analysed. Ankle brachial index (ABI) measurements were conducted before and after the endovascular procedure, and every three months thereafter. When the ABI dropped ≥ 0.15 compared with the baseline value, a duplex ultrasound was conducted to check stent patency. The outcome measures were stent patency rates, freedom from target lesion revascularisation (TLR), stent thrombosis, and acute limb ischaemia (ALI) accompanying loss of patency rates. Propensity score matching (PSM) was performed to adjust for confounding baseline characteristics.PSM extracted 219 limbs in the SG group and 109 limbs in the DES group. Compared with the SG group, the DES group had statistically significantly higher rates of freedom from TLR (86.0 ± 4.2% vs. 73.1 ± 4.8%, p = .040), and ALI accompanying loss of patency (98.9 ± 1.1% vs. 93.5 ± 1.8%, p = .029) at two years. Primary patency (75.9 ± 5.9% vs. 69.5 ± 5.9%, p = .087) and freedom from stent thrombosis (90.4 ± 3.3% vs. 81.2% ± 3.0%, p = .11) were not statistically significantly different. For lesions ≤ 15 cm, primary patency in the DES group was statistically significantly better than the SG group.FP lesions treated with Eluvia DES had a higher primary patency rate in lesions ≤ 15 cm, freedom from clinically driven TLR and ALI accompanying loss of patency than the VIABAHN SG.

A new type of ferroelectricity, originating from charge order and coupled to magnetism, occurs in YbFe2O4 containing triangular Fe/O double layers, which has recently generated great interest in this material. YbFe2O4 tolerates more than 10% iron deficiency even in bulk single crystals with space group R m. Even though a large number of Fe deficiencies are introduced in the thin film form due to vaporization of Fe ions during deposition at high temperatures, the crystal structure with the space group of R m in the films never changes within the Fe/Yb composition ratio from 1.3 to 2.2. In the previous research, the effects of the Fe/Yb composition ratio—especially in the large Fe deficient area (1.31–1.86)—on the lattice distortion and chemical bonding state of non-stoichiometric (0001)-oriented YbFe2O4 epitaxial thin films on (111) YSZ and (0001) sapphire substrates were examined. The variation of the lattice constant, Raman spectra, and optical absorption coefficient indicated that the existence of the stacking fault and the antisite Yb play an important role in the significant iron deficiency without changing the crystal structure of non-stoichiometric YbFe2O4 thin films.

The output characteristics of MEMS piezoelectric vibration energy harvesters (PVEHs) under random oscillations are analysed. We fabricated cantilever-type MEMS-PVEHs using Pb(Zr,Ti)O3 films. The autocorrelation function of the transient displacement of the cantilever tip under random oscillations features a narrow-band random vibration. From the power spectral density (PSD) of the output voltage of the PVEHs, the resonance frequency decreases and the full-width at half-maximum increases with increasing vibration acceleration. By comparing output properties under various sinusoidal oscillations, nonlinear effects including the soft-spring effect and nonlinear damping effect clearly influence the output characteristics under random oscillations. The power generation is proportional to the square of the vibration acceleration even in the acceleration region where nonlinear effects become conspicuous.

We present the design and fabrication of a 2D monolithic pixelated detector array using metalorganic vapor-phase epitaxy grown thick CdTe epitaxial layers on Si substrates. Each pixel in the array consists of a p-CdTe/n-CdTe/n+-Si heterojunction diode structure, and pixels were patterned by cutting deep vertical grooves using a dicing saw. We also developed a low-temperature conductive-epoxy based bonding technique to bond the array to the read out electronic circuit via an interface board. Preliminary evaluation shows that the fabricated array is capable of discriminating energies of the incident radiation and can be applied for the energy discriminating imaging purpose. Moreover, this fabrication technique is useful in developing larger imaging arrays.

We present reverse bias current (dark current) characteristics of a two-dimensional monolithic pixel-type nuclear radiation detector array fabricated using metalorganic vapor-phase epitaxy (MOVPE)-grown thick CdTe epitaxial layers on Si substrate. The (14 × 8) pixel array was formed by cutting deep vertical trenches using a dicing saw, where each pixel possesses a p-CdTe/ n-CdTe/n+-Si heterojunction diode structure. The dark currents showed pixel-to-pixel variations when measured at higher applied biases exceeding 100 V. The dark current had a dependence on the pixel thickness, where pixels with lower CdTe thickness exhibited higher currents. Moreover, the temperature dependence of the dark current revealed that a deep level with activation energy of around 0.6 eV is responsible for the observed dark currents and their pixel-to-pixel variation. We discuss that the effective ratio of Te to Cd at the growth surface is a major factor that controls the thickness variation, and is also responsible for the formation of 0.6 eV deep levels.

We present fabrication process of two-dimensional (2D) energy discriminating pixel-type imaging arrays. Each pixel in the array possesses a p-CdTe/n-CdTe/n+-Si heterojunction diode structure. The array is fabricated using metalorganic vapour-phase epitaxy grown thick layers of single crystal CdTe on (211)Si substrates. In order to avoid the charge sharing problem among the adjacent pixels, we used a mechanical saw based pixel pattering technique, which produced pixels that are isolated from each other by narrow vertical trenches. Preliminary evaluation with room-temperature reverse biased dark current values exhibited uniform response from the entire pixels in the array. This opens a new possibility for developing large-area imaging arrays in a simple and efficient way. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Wavelength modulation over 500 kHz by a micromechanically tunable vertical-cavity surface-emitting laser (VCSEL) consisting of an InP-based half-VCSEL chip and a micromachined silicon-on-insulator chip with a concave movable mirror has been demonstrated for the first time. A peak power of 3.5 mW, a tuning range of 55 nm, and a side-mode suppression ratio of about 60 dB have been demonstrated.

Magnetic and magnetotransport properties of a magnetic semiconductor, Si:Ce films, were investigated. The as-deposited films exhibit n-type conduction due to their amorphous nature, with a temperature dependence of the resistivity (ρ–T) like a normal semiconductor with diamagnetic properties. By annealing at 973 K, the conduction and the magnetic susceptibility change to the p-type and become positive, respectively. The change in the magnetic susceptibility (χ–T) at a low magnetic field of 750 Oe against the measurement temperature exhibits spin-glasslike behavior showing a cusp around 38 K (Tg). The ρ–T curve increases exponentially from 273 K to 35 K, and then drastically decreases by three orders of magnitude below 33 K. Above Tg, the magnetoresistance behavior at a magnetic field below 0.5 T can be understood as that of a semiconductor caused by the Lorentz force. Below Tg, on the other hand, an extremely large magnetoresistance, which can not be explained by a Lorentz force alone, is observed.

We report the dielectric relaxation in a ternary system in which a trace amount of poly(n-hexyl isocyanate) (PHIC) is dissolved in concentrated toluene solutions of polybutadiene (PB). The dielectric response is due to the rod-like PHIC molecules having high dipole moment along its chain contour. Solutions of PB form entanglement networks which retard the reorientation of the PHIC molecules. With increasing concentration (CPB) of PB from 0 to 40 wt% the relaxation behaviour changed at a crossover concentration CPB+. In the range below CPB+, the relaxation time τ for reorientation of the PHIC molecules increased on account of the effect of entanglement. However above CPB+, τ decreased and at the same time the relaxation strength decreased with increasing CPB. The crossover concentration CPB+ depended on the molecular weight M of the PHIC, i.e. C+PB=0.13 at M=29,000, and CPB+=0.25 at M=20,000. The decrease of the relaxation strength can be attributed to the reduction of the effective dipole moment due to the restriction of motions of the PHIC chains in entanglement networks of PB chains.

Membrane dysfunction induced by in vitro ischemia in immature rat hippocampal CA1 neurons. We investigated differences between immature and mature hippocampal neurons in their response to deprivation of oxygen and glucose (in vitro ischemia), using intracellular recording techniques from CA1 pyramidal neurons in rat brain slices. The membrane was more depolarized in immature hippocampal CA1 neurons (postnatal day 7, P7) compared with the adult neurons (P140), and the apparent input resistance in immature neurons was higher than that in adult neurons. In immature neurons, the threshold for action potential generation was high, and the peak amplitude of the action potential was low in comparison with adult neurons. A time-dependent inward rectification, at potentials negative than the resting potential, was prominent in neurons of P14 and P21. After P21, the resting membrane potential, the apparent input resistance, and the threshold and the peak amplitude of the action potential did not significantly change with increasing age. In adult neurons, application of ischemia-simulating medium caused irreversible changes in membrane potential consisting of an initial hyperpolarization followed by a slow depolarization and a rapid depolarization. Once the rapid depolarization occurred, reintroduction of oxygen and glucose failed to restore the membrane potential, a state referred to as irreversible membrane dysfunction. In neurons of ages P7 or P14, the initial hyperpolarization was not apparent, whereas a slow depolarization followed by a rapid depolarization was observed. With development of the neurons, the latency for onset of the rapid depolarization became shorter and its maximal slope increased. Moreover, neurons of ages P14 or P21 showed a partial or complete recovery after reintroduction of oxygen and glucose, unlike mature neurons. In summary, the present study has demonstrated that the initial hyperpolarization and rapid depolarization induced by in vitro ischemia is age dependent. The rapid depolarization is not readily produced in the neurons in age less than P21 during ischemic exposure.

For Zn1-xMnx O/ZnO heterostructures pseudomorphically grown on ZnO (000) single-crystal substrates, spontaneous and piezoelectric polarization-induced sheet charges were investigated. The sheet carrier concentration of a Zn0.88Mn0.12O/ZnO heterostructure with a 10-nm-thick ZnMnO spacer layer was determined to be 5.6×1012 cm–2 by Hall measurement. For x = 0.12, the number of free electrons induced by spontaneous and piezoelectric polarizations was calculated to be 1.8×1012 cm–2, which is less than the experimental value. This discrepancy can be explained by considering an additional electric field generated by the ZnMnO/ZnO conduction band offset and ZnMnO spacer layer. Therefore, for ZnMnO/ZnO heterostructures, the effect of electric field should also be considered together with spontaneous and piezoelectric polarizations in carrier confinement. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

To understand the intrinsic magnetic nature of ZnMnO thin films without the influence of the clustering and segregating Mn ions due to the formation of misfit dislocations and staking faults, ZnO films with the Mn concentration up to 10 at% were prepared on ( 0 0 0 1 ¯ ) ZnO single-crystal substrate by pulsed laser deposition (PLD) method. The lattice constant along the c-axis of the ZnMnO films linearly increases with increasing the Mn concentration, and that along a-axis does not change from that of ZnO substrate showing the pseudomorphic growth of the ZnMnO films. The intrinsic magnetization behavior could be obtained by using these ZnMnO films. The ZnMnO films up to 10 at% Mn exhibit typical paramagnetic nature at 1.85 K including the antiferromagnetic interaction of Mn–O–Mn superexchange.

Group-IV diluted magnetic semiconductor (DMS), Si:Ce thin films with Ce concentration below 4.0 at% were grown by low-temperature molecular beam epitaxy (LT-MBE) on (0 0 1) Si substrates. Low-temperature growth enables uniform distribution of Ce in Si without hillock and pit formations. Smooth surface and abrupt interface of Si:Ce thin film grown at the growth temperature of 430 °C were observed. Magnetic properties of Si:Ce thin films were investigated by a superconducting quantum interference device (SQUID). All the samples exhibited positive magnetization at 4.2 K. The ferromagnetic interaction was enhanced when the Si:Ce film had p-type conduction. However, the film with n-type conduction also exhibited ferromagnetic behavior when the film included high Ce concentration above 4.0 at%.

The structural, magnetic and electric properties of calcinated BaCo/sub 1-x/Mn/sub x/O/sub 3/ (x = 0.0-0.25) oxides are investigated by X-ray diffraction (XRD) and transmission electron microscopy, SQUID measurements, and conventional four-probe technique, respectively. XRD data show a 2H-type perovskite at x = 0.0, 10H-type crystal structure at x = 0.15, and mixed phases (2H- and 10H-types) at x = 0.05 and 0.10. The magnetisation-temperature curves reveal the antiferromagnetic phase of the 2H single phase and ferromagnetic behavior (brought by the observed hysteresis and remanent magnetization) at 5 K of the 10H-type structure. A transition from ferromagnetic to paramagnetic state is also observed with a transition temperature of around 47 K. Around this temperature region, specifically at 50 K, a semiconductor-insulator transition is found with a dielectric constant /spl epsiv/ = 1.13. These results suggest that the 10H-type structure around the obtained transition temperature is a possible candidate for device applications of ferromagnetic oxides with dielectric properties.

We observe the formation of an ordered structure in Si1−xGex films grown on Ge(100) substrates, as well as on Si(100) substrates, by molecular beam epitaxy. The structural characterization of these ordered films is performed. The degree of order in the films is quantitatively measured using x‐ray diffraction. The dependence of the degree of order on Ge composition is similar between films on Ge(100) and Si(100) substrates. By careful x‐ray diffraction analysis, we find that the degree of order is not equivalent in variants.

BaFeO/sub 3/ (BFO) epitaxial thin films on [001] SrTiO/sub 3/ substrates have been successfully produced by pulsed laser beam deposition. The epitaxially grown BFO was found to have tetragonal crystal structure with some amount of oxygen deficiencies. The magnetic susceptibilities of the samples strongly depended on the (hkl) directions of BFO varied in accordance with the crystalline directions, i.e., /spl chi//sub (100)/

We have prepared single-crystalline films of BaFeO3, which may contain high valent Fe4+ ions, on (100) SrTiO3 substrates by pulsed laser-beam deposition. The reflection high-energy electron diffraction patterns for the films apparently show a C4 symmetry operation, suggesting that the sample had a pseudocubic perovskite structure rather than hexagonal unit cell. The films were found to be highly insulating, and showed a high value of dielectric constant of e=59. At 300 K, the magnetization loop of the film apparently shows hysteresis, as well as small remanent magnetization. These characteristics are totally different from those of bulk BaFeO3.

A direct HPLC separation method was developed for the determination of the enantiomers of racemic precursors to diltiazem (I) and its 8-chloro derivatives (II). The enantiomers were successfully separated on a chiral ovomucoid column using an aqueous-organic mobile phase (reversed-phase HPLC). The influence of the organic modifier and buffer pH on the retention and enantioselectivity was investigated. The chromatographic conditions chosen for the separation permitted complete resolution of the enantiomers of both the acid (Ib and IIb) and methyl ester precursors (Ia and IIa) within 20 min. The influence of sample load on retention times, theoretical plates numbers, peak heights and peak areas was also investigated. The peak areas showed a good linearity over the concentration range examined, although all the others were influenced significantly by the sample size. An optical antipode of the intermediate to be determined could be detected by the area-percentage method down to ca. 0.1%, together with the determination of its precursor, including its optical purity.

Solid-state reactions of titanium thin films on Si surfaces damaged and amorphized by CHF3/O2 plasma treatment were investigated. The formation temperature of the C49–TiSi2 phase increased due to plasma-induced damage and contamination from decomposed gas elements. The presence of a plasma-induced damage layer suppressed the interdiffusion of Ti and Si. The Ti5Si3 phase was formed initially at an annealing temperature of 400 °C when a plasma-induced damage layer was present at the interface. The increase of the C49–TiSi2 formation temperature may be caused by the transformation of the Ti5Si3 phase into C49–TiSi2 rather than by the direct nucleation of the C49–TiSi2 phase with a clean interface.

The basis-set expansion method has been applied to the nonrelativistic and relativistic ground states of one-electron atoms H, Ar17+, Xe53+, Hg79+, and U91+ in the uniformly charged sphere (UCS) and the point-change (PC) models of atomic nucleus, using the Gaussian-type basis functions. The energies and the radial expectation values, especially 1/r2, converges faster in the UCS model than in the PC model. In the PC model, larger values of the exponent parameters of the basis functions are required both in the nonrelativistic and the relativistic calculations. Even in the UCS model, the larger values of the exponent parameters are needed in the relativistic calculations.

We have adopted the uniformly charged sphere model of atomic nucleus for one-electron atoms H, Ar17+, Xe53+, Hg79+, and U91+ and calculated several energy levels by solving the matching equations of the inward and the outward radial wave functions for the Schrodinger as well as for the Dirac equations. The finite-size effect (FSE) of the atomic nucleus on the energy levels of nonrelativistic atoms has been found one order of magnitude smaller than the effect on the relativistic atoms. The FSE works mainly on s states for nonrelativistic atoms, whereas for relativistic atoms, it works on s and p1/2 states. The energy levels of p states have been calculated lower than the energies of the corresponding s states when we have included the FSE.

A reversed-phase high-performance liquid chromatographic (HPLC) method was developed to determine the optical purity of denopamine, which is a new cardiotonic agent having an asymmetric carbon in a molecule. The enantiomers were converted to diastereomeric thiourea derivatives using 2,3,4,6-Tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate (GITC) reagent. Separation of the enantiomers of denopamine as diastereomers was successfully achieved by reversed-phase HPLC within 10 min using an ODS column and UV detection. Derivatization of denopamine proceeded rapidly under the alkaline conditions and the ambient temperature. This method was applied to the determination of the optical purity of denopamine drug substances and those in tablets. The favorable UV absorption of the derivatives enabled the optical antipode to be determined down to the 0.2% level.

Eight asthmatic patients with hard metal asthma due to cobalt underwent bronchial provocation challenge with nickel sulphate. Seven patients developed a fall in FEV1 of 20% or more after inhaling nickel sulphate, four showing an immediate response and three a late response. Eight control subjects, including six asthmatic patients, with no history of hard metal exposure, showed no bronchoconstriction in response to a provocation challenge with nickel sulphate. Specific antibodies to nickel conjugated human serum albumin were present in four of the eight patients with sensitivity to cobalt conjugated human serum albumin but were absent from the serum of 60 unexposed asthmatic patients and 25 exposed symptom free workers. These results suggest that nickel as well as cobalt sensitivity plays a part in hard metal asthma.

A model of the ordering mechanism in SiGe films is developed to explain the occurrence of two types of ordered structures. We investigate the stability of ordered structures by strain energy calculation. It is suggested that atomic diffusion, which is enhanced by strain in a film, influences the formation of ordered structures. The process of atomic exchange that forms the ordered structure at a reconstructed surface during growth is also discussed.

We propose a novel speech processing framework, where all of the speech data are encoded into universal phonetic code (UPC) sequences and speech processing systems, such as speech recognition, retrieval, digesting, etc., are constructed on this UPC domain. As the first step, we introduce a sub-phonetic segment (SPS) set, based on IPA (international phonetic alphabet), to deal with multilingual speech and develop a procedure to estimate acoustic models of the SPS from IPA-like phone models. The key point of the framework is to employ environment adaptation into the SPS encoding stage. This makes it possible to normalize acoustic variations and extract the language factor contained in speech signals as encoded SPS sequences. We confirm these characteristics by constructing a speech retrieval system on the SPS domain. The system can retrieve key phrases, given by speech, from different environment speech data in a vocabulary-free condition. We show several preliminary experimental results on this system, using Japanese and English sentence speech sets.

A diluted magnetic semiconductor, Si:Ce thin films with the Ce concentration below 4.3 at%, were prepared by solid source molecular beam epitaxy. The lattice constant of the Si:Ce film increases with increasing the Ce concentration, while it decreases above Ce 0.2 at%. Magnetization measured at 4.2 K for the samples with the Ce concentration up to 0.2 at% also increases with increasing the Ce concentration up to 0.2 at%. The amount of substituted Ce in Si is considered to play an important role for the magnetic properties.

This paper proposes a novel speech processing framework, where all of the speech data are once encoded into universal phonetic code (UPC) sequences and speech processing systems, such as speech recognition, retrieval, digesting, are constructed on this UPC domain. First of all, we introduce an IPA-based sub-phonetic segment (SPS) set as the UPC to deal with multilingual speech. In the UPC (SPS) domain, each UPC accompanies a reference acoustic model which is independent of real acoustic models used in the encoding process. Processing, such as recognition, in the UPC domain is conducted based on the distance between UPC sequences estimated by using the reference acoustic models. We confirm the proposed framework by constructing a speech recognition and a vocabulary-free speech retrieval system on the SPS domain. We show several experimental results on these systems, using Japanese and English speech data sets.

The memory retention properties of Pt/YMnO3/Y2O3/Si capacitors were investigated for the application of ferroelectric gate transistors. The epitaxially grown Pt/YMnO3/Y2O3/Si capacitors showed ferroelectric type hysteresis loop on the capacitance-voltage properties. Although the retention time of the as-deposited capacitors was ∼103 s, it was prolonged up to 104 s when the leakage current density was reduced from 4×10−8 A/cm2 to 2×10−9 A/cm2 by the annealing under N2 ambience. To reveal the relationship between the retention time and leakage current, the leakage current mechanism was investigated comparing several conduction mechanisms. It was found that the dominant leakage mechanisms at high and low electric fields were Poole-Frenkel emission from the Y2O3 layer and ohmic conduction, respectively. This result indicates that the leakage current was limited by the Y2O3 layer at high electric field and was mainly dominated by the amount of defects in the YMnO3 layer at low electric field. From the pseudo isothermal capacitance transient spectroscopy (ICTS), it was determined that the trap density was in an order of 1015 cm−3. Since the variation of the leakage current by annealing was observed only in the low electric field region, it is suggested that the retention properties of the Pt/YMnO3/Y2O3/Si capacitors was influenced by the amount of defects in the YMnO3 layer.

We have much difficulty in developing good software efficiently for embedded microprocessors (MPs) because of insufficient requirements analysis and incomplete product specification. To improve the situation, we often consider adopting an upper CASE tool. However, it is not clear that an upper CASE tool is effective in developing software for embedded MPs. We researched the software development environments and the use of upper CASE tools in Japan and the USA. As a result, we found differences in the software development environments of the two countries, and particularly we found differences in the use, effects and evaluation of upper CASE tools. It seems that Japanese vendors have not used upper CASE tools in an expedient way yet. >

Tongue swelling after surgery is a rare but potentially lethal postoperative complication. This is a case report of a 62-yr-old patient who developed tongue swelling after intraoperative monitoring by transesophageal echocardiography. The patient underwent replacement of the descending aorta with an interposition graft under cardiopulmonary bypass. A transesophageal echocardiography (TEE) probe was inserted after the induction of general anesthesia. Surgery and anesthesia were uneventful. After the surgical procedure, the TEE probe was removed. At that time, marked swelling of the tongue was noted. However, there was no diffuse edema in the neck, face, supraglottic structures or the larynx. The tongue swelling was thought to have been caused by local mechanical compression of the tongue with the TEE probe. The tongue returned to normal size the next day. Care should be taken to prevent the occurrence of this complication during and after TEE examination under general anesthesia.

Septate cytoplasmic vacuoles, which are one of the cytologic findings characteristic of papillary thyroid carcinoma, are small, uniform, and well-defined vacuoles, with defined strands of cytoplasm separating them. We report on a case with histologic and ultrastructural findings corresponding to septate cytoplasmic vacuoles, which have not been previously described. The patient was a 51-yr-old man with a mass in the left anterior of the neck, measuring 4.0 x 3.5 cm in diameter. Aspiration cytology smears revealed findings typical of papillary thyroid carcinoma, including papillary tissue fragments, intranuclear inclusions, nuclear grooves, powdery chromatin, and psammoma bodies. The tumor cells which were located at the periphery of small three-dimensional clusters, and others which showed a sheet-like arrangement, demonstrated uniform, small vacuoles in relatively abundant, dense cytoplasm. Histologically, a small number of papillary thyroid carcinoma cells with multiple vacuoles were observed, which were limited to the hobnail-shaped cells located at papillary configurations or floating tumor cells within the papillary lumen. Ultrastructurally, the hobnail-shaped tumor cells demonstrated various-sized dilated rough endoplasmic reticulum and rich heterochromatin. We emphasize that septate cytoplasmic vacuoles correspond to dilated rough endoplasmic vacuoles and are probably related to degenerative changes.

We examined clinical features and outcomes of mechanically ventilated patient (n = 11) retrospectively who had developed acute respiratory failure during treatments with immunosuppressive drugs. The mean APACHE II score was 22.6, and the mean lung injury score was 2.9. In eight patients chest X-ray and computed tomography showed interstitial pneumonia. Fungus and/or cytomegalovirus were isolated most often from patients with interstitial pneumonia. Observed mortality (72.7%) was significantly (P0.001) higher than predicted mortality (45.1%) in the APACHE II score. Patients, who were complicated with septic shock caused by fungus infection, showed poor mortality. These results suggest that the fungus and cytomegalovirus infections might be associated with poor prognosis in patients with acute respiratory failure during treatment with immunosuppressive drugs.

Phosphodiesterase (PDE) inhibitors are occasionally used in patients receiving non-depolarizing muscle relaxants during anesthesia and intensive care. However, little is known about the influence of PDE III inhibitors on the effects of non-depolarizing muscle relaxants. The aim of this study was to elucidate the effects of milrinone, a PDE III inhibitor, on d-tubocurarine (dTc)-induced muscle relaxation in vitro and then to compare its effects with those of other activators of the adenylate cyclase (AC) system (aminophylline, a non-selective PDE inhibitor; forskolin, a direct AC activator; and isoproterenol, a beta-adrenoceptor agonist). Isometric twitch tensions of rat nerve-hemidiaphragm preparations elicited by indirect or direct stimulation (0.1 Hz) were measured. Indirectly elicited twitch tension partially depressed by dTc (1 microM) was antagonized by milrinone, aminophylline, and forskolin but was attenuated by isoproterenol. Directly elicited twitch tension was increased by aminophylline, forskolin, and isoproterenol but was not altered by milrinone. The results indicate that milrinone antagonizes dTc-induced muscle relaxation by recovering the neuromuscular transmission. It is noteworthy that PDE inhibitors and a beta-adrenergic agonist affect non-depolarizing muscle relaxation in opposite direction.

Prolonged effects of non-depolarizing muscle relaxants in septic patients have been reported, although the influence of sepsis on neuromuscular transmission has not yet been clarified satisfactorily. These studies were intended to elucidate the influence of sepsis on neuromuscular transmission and on the action of drugs being utilized for regulation of muscle tone (a neuromuscular blocker and anti-cholinesterase (anti-ChE) drugs).The effect of d-tubocurarine (dTc) on neuromuscular transmission and the antagonistic action of anti-ChE drugs (neostigmine and edrophonium) on dTc-induced twitch depression were estimated using sham control and septic rat nerve-hemidiaphragm preparations in vitro. Isometric twitch tension elicited by indirect (phrenic nerve) or direct (muscle) stimulation at 0.1 Hz was evaluated.Sepsis induced by panperitonitis attenuated the twitch tension elicited by indirect or direct stimulation (P0.01) without obvious morphological inflammatory damage to the diaphragm. dTc dose-dependently decreased twitch tension elicited by indirect stimulation (P0.01) less intensely in the septic group than in the sham group (P0.01). The antagonistic actions of the anti-ChE drugs on dTc (1 microM)-induced twitch depression were less intense in the septic group (P0.01 or 0.05).These results demonstrate that sepsis in the acute phase attenuates the effects of a neuromuscular blocker and anti-ChE drugs and depresses muscle contractility simultaneously.

We report a case with radical neck clipping following incomplete embolization with coils and imperfect neck clipping. A 43-year-old woman suffered from a subarachnoid hemorrhage (HuntHess Grade IV) due to the rupture of a left paraclinoid internal carotid aneurysm on 28 October, 1996. Neck clipping of the aneurysm was performed at day 1. Follow-up angiogram at 2 weeks after surgery showed however a small residual aneurysm. The second angiogram 1.5 months later showed the growth of the residual aneurysm. The residual part of the aneurysm was then treated with endovascular embolization using interlocking detachable coils (IDC), resulting in incomplete occlusion of the aneurysm. The direct surgical clipping of the residual aneurysm was performed via Dolenc approach. A fenestrated clip was applied to the partial embolized aneurysm, when the aneurysmal wall was ruptured between the occluded part of the aneurysm and the residual dome. The fenestrated clip was then reapplied successfully under temporary occlusion of the parent artery. Because of the stenosis of the parent artery, STA-MCA anastomosis was then performed. Postoperative recovery of the patient was uneventful and postoperative angiogram showed stenosis of the parent artery with patent bypass flow. The patient was discharged without complications. Technical problems in neck clipping following incomplete embolization with coils are discussed.

Fujimura, N., E. Tanaka, S. Yamamoto, M. Shigemori, and H. Higashi. Contribution of ATP-sensitive potassium channels to hypoxic hyperpolarization in rat hippocampal CA1 neurons in vitro. J. Neurophysiol. 77: 378–385, 1997. To investigate the mechanism of generation of the hypoxia-induced hyperpolarization (hypoxic hyperpolarization) in hippocampal CA1 neurons in rat tissue slices, recordings were made in current-clamp mode and single-electrode voltage-clamp mode. Superfusion with hypoxic medium produced a hyperpolarization and corresponding outward current, which were associated with an increase in membrane conductance. Reoxygenation produced a further hyperpolarization, with corresponding outward current, followed by a recovery to the preexposure level. The amplitude of the posthypoxic hyperpolarization was always greater than that of the hypoxic hyperpolarization. In single-electrode voltage-clamp mode, it was difficult to record reproducible outward currents in response to repeated hypoxic exposure with the use of electrodes with a high tip resistance. The current-clamp technique was therefore chosen to study the pharmacological characteristics of the hypoxic hyperpolarization. In 60–80% of hippocampal CA1 neurons, glibenclamide or tolbutamide (3–100 μM) reduced the amplitude of the hypoxic hyperpolarization in a concentration-dependent manner by up to ∼70%. The glibenclamide or tolbutamide concentrations producing half-maximal inhibition of the hypoxic hyperpolarization were 6 and 12 μM, respectively. The chord conductance of the membrane potential between −80 and −90 mV in the absence of glibenclamide (30 μM) or tolbutamide (100 μM) was 2–3 times greater than that in the presence of glibenclamide or tolbutamide. In contrast, the reversal potential of the hypoxic hyperpolarization was approximately −83 mV in both the absence and presence of tolbutamide or glibenclamide. In ∼40% of CA1 neurons, diazoxide (100 μM) or nicorandil (1 mM) mimicked the hypoxic hyperpolarization and pretreatment of these drugs occluded the hypoxic hyperpolarization. When ATP was injected into the impaled neuron, hypoxic exposure could not produce a hyperpolarization. The intracellular injection of the nonhydrolyzable ATP analogue 5′-adenylylimidodiphosphate lithium salt reduced the amplitude of the hypoxic hyperpolarization. Furthermore, application of dinitrophenol (10 μM) mimicked the hypoxic hyperpolarization, and the dinitrophenol-induced hyperpolarization was inhibited by either pretreatment of tolbutamide or intracellular injection of ATP, indicating that the hypoxic hyperpolarization is highly dependent on intracellular ATP. It is therefore concluded that in the majority of hippocampal CA1 neurons, exposure to hypoxic conditions resulting in a reduction in the intracellular level of ATP leads to activation of ATP-sensitive potassium channels with concomitant hyperpolarization.