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Ventilation in the prone position improves the prognosis of patients with severe acute respiratory distress syndrome (ARDS). Contraindications to ventilation in this position include unstable systemic circulation. Only a few reports exist on the effects of prone ventilation in respiratory failure on systemic circulation. This animal study compared systemic hemodynamic changes between supine and prone positions in anesthetized rabbits under acute systemic hypoxia (breathing 15% O(2)). Cardiac output and the systemic O(2) extraction ratio increased under the hypoxia, but only in the supine group. Besides, the rate pressure product was higher in the prone group than in the supine group. This study showed that prone ventilation increases myocardial O(2) consumption and suppresses compensatory mechanisms to maintain aerobic metabolism during systemic hypoxia. First of all, it will be necessary to examine the effect of prone ventilation on the O(2) supply-demand balance in the ARDS model.

BACKGROUND: Breathing during a marathon is often empirically conducted in a so-called “2:2 breathing rhythm,” which is based on a four-phase cycle, consisting of the 1st and 2nd inspiratory and the 1st and 2nd expiratory phases. We developed a prototype ventilator that can perform intermittent positive pressure ventilation, mimicking the breathing cycle of the 2:2 breathing rhythm. This mode of ventilation was named the marathoners’ breathing rhythm ventilation (MBV). We hypothesized that MBV may have a lung protective effect. METHODS: We examined the effects of the MBV on the pulmonary pre-edema model in isolated perfused rabbit lungs. The pulmonary pre-edema state was induced using bloodless perfusate with low colloid osmotic pressure. The 14 isolated rabbit lung preparations were randomly divided into the conventional mechanical ventilation (CMV) group and MBV group, (both had an inspiratory/expiratory ratio of 1/1). In the CMV group, seven rabbit lungs were ventilated using the Harvard Ventilator 683 with a tidal volume (TV) of 8 mL/kg, a respiratory rate (RR) of 30 cycles/min, and a positive end-expiratory pressure (PEEP) of 2 cmH(2)O for 60 min. In the MBV group, seven rabbit lungs were ventilated using the prototype ventilator with a TV of 6 mL/kg, an RR of 30 cycles/min, and a PEEP of 4 cmH(2)O (first step) and 2 cmH(2)O (second step) for 60 min. The time allocation of the MBV for one cycle was 0.3 s for each of the 1st and 2nd inspiratory and expiratory phases with 0.2 s of intermittent resting between each phase. RESULTS: Peak airway pressure and lung wet-to-dry ratio after 60 min of ventilation were lower in the MBV group than in the CMV group. CONCLUSION: MBV was considered to have a lung-protective effect compared to CMV.

Small gauze is used in laparoscopy; therefore, retention of gauze can occur. We experienced a case of retention of a radiopaque thread that ruptured from a piece of gauze and moved into the peritoneum during a scheduled laparoscopy. The patient was a 65-year-old woman who underwent laparoscopic-assisted transverse colon resection for transverse colon cancer. A commercial gauze commonly used for laparoscopy was used during the surgery. To more easily identify the gauze during surgery, radiopaque threads extending up to 3.0 cm from the two diagonal corners of the gauze body were attached. After wound closure, radiography showed a radiopaque thread-like substance in the abdomen. Minor laparotomy was performed, and part of the radiopaque thread was discovered. On postoperative day 22, the patient was in remission and discharged.

Background Isoflurane and sevoflurane protect lungs with ischemia–reperfusion (IR) injury. We examined the influence of desflurane on IR lung injury using isolated rabbit lungs perfused with a physiological salt solution. Methods The isolated lungs were divided into three groups: IR, desflurane-treated ischemia–reperfusion (DES-IR), and ventilation/perfusion-continued control (Cont) groups (n = 6 per group). In the DES-IR group, inhalation of desflurane at 1 minimum alveolar concentration (MAC) was conducted in a stable 30-min phase. In the IR and DES-IR groups, ventilation/perfusion was stopped for 75 min after the stable phase. Subsequently, they were resumed. Each lung was placed on a balance, and weighed. Weight changes were measured serially throughout this experiment. The coefficient of filtration (Kfc) was determined immediately before ischemia and 60 min after reperfusion. Furthermore, bronchoalveolar lavage fluid (BALF) was collected from the right bronchus at the completion of the experiment. After the completion of the experiment, the left lung was dried, and the lung wet-to-dry weight ratio (W/D) was calculated. Results The Kfc values at 60 min after perfusion were 0.40 ± 0.13 ml/min/mmHg/100 g in the DES-IR group, 0.26 ± 0.07 ml/min/mmHg/100 g in the IR group, and 0.22 ± 0.08 (mean ± SD) ml/mmHg/100 g in the Cont group. In the DES-IR group, the Kfc at 60 min after the start of reperfusion was significantly higher than in the other groups. In the DES-IR group, W/D was significantly higher than in the Cont group. In the DES-IR group, the BALF concentrations of nitric oxide metabolites were significantly higher than in the other groups. In the DES-IR group, the total amount of vascular endothelial growth factor in BALF was significantly higher than in the Cont group. Conclusions The pre-inhalation of desflurane at 1 MAC exacerbates pulmonary IR injury in isolated/perfused rabbit lungs.

The relationship between abrasive particle size and polishing rate (PR) of a chemical mechanical polishing (CMP) process is studied both experimentally and theoretically. PR of NiP-plated aluminum substrates polished by spherical silica particles of a uniform size becomes the maximum around at 50nm in particle size. A simple mechanical model for CMP is proposed to describe this behavior. It is also shown experimentally that mixing silica particles of different sizes can enhance PR.

Phosphoenolpyruvate (PEP) is an intermediate metabolite of the glycolytic pathway and an in vivo high-energy phosphate compound. We have examined the protective effects of PEP on ischemia–reperfusion lung injury in isolated rabbits lungs perfused with a physiological salt solution. The lungs were divided into three treatment groups: (1) ischemia–reperfusion (IR), (2) ischemia–reperfusion with PEP treatment (PEP-IR), in which 1 mM PEP was pre-administered into the perfusate during the stable period, and (3) ventilation–perfusion continued without interruption (Cont). In the IR and PEP-IR groups, ventilation–perfusion was discontinued for about 60 min after a 30-min stable period and then restarted. The capillary filtration coefficients (K fc) and pyruvate concentration in the perfusate were determined immediately before ischemia and 30 and 60 min after reperfusion. The left lungs were dried at the end of the experiment to calculate the tissue wet-to-dry weight ratio (W/D). The K fc values after reperfusion were significantly higher in the IR group than in the other two groups. Pyruvate concentrations were significantly higher at three time-points in the PEP-IR group than in the other two groups. The W/D was significantly higher in the IR group than in the other two groups. Based on these results, we conclude that the administration of PEP prior to lung ischemia alleviates lung ischemia–reperfusion injury.

Oligothiophene cation radical salts were first prepared by the electrochemical oxidation method employing large-sized anions PF6−, AsF6, TaF6, BF4 and GaCl4. Several large-sized anions (AsF6, TaF6 and GaCl4) gave black-needle crystalline salts. All the salts showed semiconductive behavior with the electrical conductivities of 10−4–10−6 S/cm. Electrical conductivity and spectroscopic measurements on the cation radical salts have suggested that oligothiophene moiety in the present salts is highly oxidized, as in oligothiophene doped with nitrosyl salt.

The real part of a.c. conductivity of C 60 -doped poly( o -ethylaniline) (PEA) has been measured to analyze the a.c. conduction mechanism in the frequency range 10 1 –10 7 Hz. A clear difference was seen in the frequency dependence of the conductivity between the pristine and the C 60 -doped PEA samples. It has been concluded that the quantum-mechanical tunneling (QMT) model accounts for the a.c. conduction mechanism of these samples, although certain reservation should be made for the C 60 -doped PEA. There is no polaron hopping in the present polymer system, since C 60 cannot generate enough numbers of positive polarons in the polyaniline skeleton.

The band structure of orthorhombic Rb 1 C 60 ( o -Rb 1 C 60 ) using the crystal structure obtained by X-ray diffraction measurements was studied based on the tight-binding calculation including both σ and π electrons. The Fermi surface of this substance shows a certain nesting property in the plane perpendicular to the Γ-H direction but is three-dimensional due to the interchain interaction. The bandwidth is still smaller by one order of magnitude than the on-ball Coulomb repulsion U , in spite of some increase due to the interchain interaction.

The electronic properties of the polymer models involving C 60 molecules incorporated into either polymer skeleton or side chain are first examined based on the one-dimensional (1D) tight-binding crystal orbital method in the framework of the extended Huckel approximation. The band structure characteristic of each polymer model is discussed particularly with respect to the interruption of the π-conjugation of the rest of the main chain.

Electronic properties of p-type doped oligothiophenes have been studied based on the electron spin resonance (ESR) and the molecular orbital (MO) calculation analyses. It has been found that in the lightly doped regime dimer cation radicals of oligothiophenes are generated and that in the heavily doped regime singlet dimer dications are partially formed.

Doping effect of C60 on polyaniline has been re-examined using soluble polyanilines (poly(o-ethylaniline) and poly(o-phenetidine)), for which inert solvent to C60 can be used. An increase in the electrical conductivity from 5.0 × 10 −9 to 1.8 × 10 −7 S/cm has been found in the emeraldine-base form of poly(o-ethylaniline). With the combination of the electron spin resonance, infrared absorption and ultraviolet and visible absorption measurements for the C60-doped soluble polyanilines, C60 can have a rather weak charge-transfer interaction with these polymers generating no appreciable numbers of polarons in the polyaniline main chain.

When the applied cricoid pressure is too strong, or the place or direction of the pressure application is not appropriate, glottal closure may occur, but its details are unclear.We evaluated possible changes in the size of the rima glottides due to backward pressure on the cricoid cartilage or backward pressure or backward, upward, and rightward pressure (BURP) on the thyroid cartilage using a video laryngoscope (Fine View' Laryngoscope, Tray Medical, Tokyo) in 6 adult males and 6 females with Cormack and Lehane grade 1.The right-to-left distance of the rima glottides was 5.1 +/- 1.2 mm without pressure application but was reduced to 3.8 +/- 1.7, 3.5 +/- 1.8, 2.8 +/- 1.9, 2.4 +/- 1.8, and 2.6 +/- 1.2 mm by 20 N and 30 N backward pressure on the cricoid cartilage and 20 N and 30 N backward pressure and BURP on the thyroid cartilage, respectively. Compared with the absence of pressure application, 20 N and 30 N backward pressure and BURP on the thyroid cartilage significantly reduced it. It was reduced to 1 mm by 30 N backward cricoid pressure in 1 patient while glottal closure occurred due to 30 backward thyroid pressure in 1 patient.The right-to-left distance of the rima glottides was significantly reduced by backward pressure or BURP on the thyroid cartilage, and was also markedly reduced by cricoid pressure in 1 of the 12 patients.

Phosphoenolpyruvate (PEP) is a glycolytic substrate which can be metabolized to pyruvate with concomitant formation of ATP. We examined the effects of PEP on hypoxic pulmonary vasoconstriction (HPV).Isolated rabbit lungs (n = 6) were reperfused at a flow rate of 40 ml x kg(-1) body weight x min(-1) with a mixture of the physiological salt solution and autologous blood. They were ventilated with a mixture of 21% O2, 5% CO2, and balance N2. The HPV response was induced by reduction of inspired O2 concentration from 21 to 3% for 5 min and was evaluated by an increase of the pulmonary arterial pressure (PAP) with inhalation of nitric oxide (NO) at concentration of 0, 10, 20 ppm in random order. Next, PEP with the final concentration of 10 mM was added to the reservoir. After 30-min equilibration, the above protocol of hypoxic stimulations was repeated.PEP did not alter the basal PAP, but augmented the HPV response. Without and with PEP, inhaled NO depressed the HPV response in a dose-related manner and the half inhibition values (ED50) were 9.4 +/- 2.2, 14.9 +/- 10.3 ppm (mean +/- SD), respectively.The combination of intravenous PEP and inhaled NO may improve PaO2 without increasing PAP in acute respiratory failure.

Continuous epidural administration of droperidol at 2.5 mg x day(-1) or less was performed in 837 patients after surgery. In 4 of these patients, an extrapyramidal reaction occurred. Patient 1 was a 10-year-old girl who developed the symptom 29 hours after the start of administration, with a total dose of 3.0 mg. Patient 2 was a 16-year-old girl in whom the symptom occurred 24 hours after the start, with a total of 5.3 mg. Patient 3 was a 22-year-old female with the symptom occurring 26 hours after the start, with a total of 5.2 mg. Patient 4 was a 74-year-old female in whom the symptom occurred 24 hours after the start, with a total of 1.3 mg. With respect to the age distribution, the total of 837 patients consisted of 16 patients aged 10 to 19 years, 85 patients aged 20 to 29 years, 91 patients aged 30 to 39 years, 90 patients aged 40 to 49 years, 77 patients aged 50 to 59 years, 148 patients aged 60 to 69 years, 240 patients aged 70 to 79 years, 97 patients aged 80 to 89 years, and 9 patients aged 90 to 99 years. Extrapyramidal reactions related to epidural administration may readily develop at younger ages.

The electronic structure of a C60-polymer chain was studied based on the tight-binding calculation including both σ and π electrons. The C60-polymer turns out semiconducting with a finite band gap (ca 1.1 eV) and its lowest unoccupied (LU) band is no more degenerate. The LU bandwidth of this polymer is generally smaller than that of A3C60 by more than one order of magnitude around the Fermi level assuring that C60−1-polymer (o-RbC60) is a strongly correlated system ( U t ⪢ 1 ) and can have the antiferromagnetic ground state. Such reduction of t comes from the cut of π-conjugation on the surface of C60 molecule by the bridging.

The reduction of micro-waviness (Wa), roll-off, micro-bump, scratch, and surface residue is required of a substrate for ultrahigh (over 80Gbit/in/sup 2/) magnetic recording density. Wa for 80Gbit/in/sup 2/ substrates can be achieved in using the slurry including the smaller particle size abrasive and the polishing rate accelerating technique of first polishing slurry (1P-slurry) and second polishing slurry (2P-slurry).

The role of volatile anaesthetics on nitric oxide (NO)-dependent relaxation is unclear in the pulmonary circulation. We examined the effects of isoflurane on NO-dependent relaxation in isolated perfused rabbit lungs.Eighteen rabbit lungs were perfused in a constant-flow recirculation manner. In study 1 (n = 12), acetylcholine (ACh, 4 x 10(-10)-10(-8) M) or nitroglycerine (NTG, 6 x 10(-10)-10(-8) M) was cumulatively injected into the pulmonary artery in the absence or presence of isoflurane (1, 2 MAC). In study 2 (n = 6), ACh was injected as in study 1 in the presence or absence of N omega-nitro-L-arginine methyl ester (L-NAME, 100 microM), an NO synthesis blocker. In all experiments, indomethacin was administered to prevent formation of vasoactive prostanoid metabolites, and the pulmonary vessels were preconstricted with prostaglandin F2 alpha (PGF2 alpha) infused before ACh or NTG injection. The ACh- or NTG-induced relaxation was expressed as % decrease in PGF2 alpha preconstriction.Isoflurane at 2 MAC attenuated the dose-dependent relaxation to ACh at doses of 4 x 10(-9) M and 4 x 10(-8) M from 27.8 +/- 4.3% and 38.8 +/- 5.3% to 17.0 +/- 3.5% and 25.5 +/- 4.9%, respectively (P0.05). Isoflurane did not change the dose-dependent relaxation to NTG and L-NAME abolished the ACh-induced relaxation.Isoflurane inhibited NO-dependent relaxation in the pulmonary circulation at a site distal to the endothelial cell receptor-mediated responses but proximal to guanylate cyclase activation of vascular smooth muscle. Acetylcholine-induced relaxation in isolated perfused rabbit lungs was regulated primarily by NO.