Simultaneous measurement of surface tension and kinematic viscosity using thermal fluctuations

We have developed a surface laser-light scattering apparatus to measure simultaneously surface tension and kinematic viscosity. In this method, we can obtain the surface properties by the laser heterodyne detection of light scattered from thermally excited capillary waves (called ripplon), which are typically of low amplitude (1 nm) and a characteristic wavelength (100m). Two gratings (d=100 and 200m) were employed to select the wave number of the capillary waves and to produce a reference beam for heterodyne detection. It was found through an experimental study on water that this contact-free method has considerable potential for application to measurements under extreme conditions such as high temperatures and high pressures.Paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24, 1994, Boulder, Colorado, U.S.A.     

Segmental liver resections for hilar cholangiocarcinoma

BACKGROUNDS/AIMS: Liver resection for hilar cholangiocarcinoma is now popular, and combined en bloc resection of the caudate lobe has become general practice, especially in Japan and some European countries. However, surgical procedure is not yet standardized, and many problems concerning surgical treatment of this disease still remain unsolved. METHODOLOGY: From April 1977 to December 1996, 173 patients with hilar cholangiocarcinoma were treated at The First Department of Surgery, Nagoya University Hospital. Of the 173 patients, 138 patients underwent surgical resection, including 124 liver resections and 14 bile duct resections. RESULTS: Several kinds of hepatic segmentectomy with en bloc resection of the caudate lobe were performed in the 124 patients: 109 underwent hepatic lobectomy or more extensive resection including central bisegmentectomy; 15 received resection of one or less segment of the liver. Aggressive resections, including combined portal vein and liver resection (n = 41) and hepatopan-creatoduodenectomy (n = 16), were applied to advanced hilar cholangiocarcinoma. The hospital death rate in hepatectomized patients was 9.7% (12/124). The 3- and 5-year rates for the 97 patients with curative hepatectomy were 42.7%, and 25.8%, respectively. CONCLUSIONS: Aggressive liver resection improves survival of patients with hilar cholangiocarcinoma. Resection procedures should be designed based on a precise diagnosis of the extent of carcinoma.     

Pharmacokinetic re-evaluation and phase I study of high dose epirubicin in advanced non-small cell lung cancer

We performed a phase I trial to evaluate the toxicity and the maximum tolerated dose of high dose epirubicin on a three-consecutive-day schedule on Japanese patients with advanced non-small cell lung cancer. Fourteen patients were entered in the study. At least three patients were assigned to each different dose level. Epirubicin was given intravenously daily for three day by bolus injection. The dose was started at 60 mg/m2/course and escalated by 30 mg/m2/course. Granulocytopenia was found to be the dose limiting toxicity with a maximum tolerated dose of 150 mg/m2/course. Thrombocytopenia and non-hematological toxicities were mild and well tolerated. The maximum tolerated dose was lower than that in Europe and Canada. Partial responses were observed in two out of five patients on 150 mg/m2/course. The recommended phase II dose for high dose epirubicin was demonstrated to be 120 mg/m2/course. A further dose-escalating study of epirubicin in conjunction with the administration of granulocyte colony stimulating factor is scheduled for the determination of its antitumor activity in non-small cell lung cancer.     

Free-space-wave drop demultiplexing waveguide device fabricated by use of the interference exposure method

Integration of free-space-wave add-drop multiplexers that consist of focusing grating couplers (FGCs) and distributed Bragg reflectors (DBRs) in thin-film waveguides have been investigated for construction of an intraboard wavelength-division-multiplexing optical interconnection. Compact optics of a Lloyd mirror configuration and a contact-type mask aligner were combined as an interference exposure system for fabrication of DBRs of 300 microm coupling length. DBRs were integrated with FGCs on a thin-film waveguide on a glass substrate for two-channel wavelength-drop demultiplexing from guided waves to free-space waves. Measured outcoupled wavelengths of two free-space waves from two pairs of a FGC and a DBR agreed with the design values of 845 and 849 nm.     

Effects of locally administered argatroban on restenosis after balloon angioplasty: experimental and clinical study

1. This study was undertaken to evaluate the preventive effects of locally administered argatroban, a competitive inhibitor of thrombin-induced platelet activation, on restenosis after balloon angioplasty. 2. A hydrogel-coated balloon catheter was immersed three times in argatroban/saline solution (1 mg/mL) for 60 s, inflated to a pressure of 606 kPa and left in the rabbit common carotid artery for 1 min. The same procedure was performed, without drug, as a control. The pharmacokinetics of delivered argatroban in the arterial wall were assessed using [14C]-argatroban. Platelet deposition 2 h after balloon injury was quantified by fluorescence studies using antiplatelet antibody. Vascular smooth muscle cell (VSMC) proliferation 3 days after balloon injury was assessed by immunohistochemical staining for proliferative cell nuclear antigen (PCNA). In a clinical study, we divided 50 elective patients into two groups: argatroban and control. 3. In the experimental study, the mean quantities of argatroban at 0, 2 and 6 h after deflation were 24.63, 0.49 and 0.11 nmol/g wet weight of artery, respectively. Argatroban was undetected 24 h after deflation. Two hours after deflation, argatroban-treated arteries showed less platelet adhesion than saline-treated controls. The mean number of PCNA-positive cells was 16.9 and 43.8% in the argatroban and control groups, respectively (P < 0.01). In the clinical study, the mean late gain loss was 8.2 and 27.3% in the argatroban and control groups, respectively (P < 0.05). The mean late restenosis rate was 11.1 and 41.4% in the argatroban and control groups, respectively (P < 0.05). 4. These data suggest that blood coagulation plays a significant role in VSMC proliferation after balloon injury and that locally administered argatroban using hydrogel-coated balloon catheter may prevent post-percutaneous transluminal coronary angioplasty restenosis.     

Structure-activity relationships of spontaneous nitric oxide releasers, FK409 and its derivatives

(+/-)-(E)-4-Ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (FK409) shows both potent in vitro vasorelaxant and antiplatelet activities via nitric oxide (NO) generated spontaneously from the compound. In this study, we measured spontaneous NO-releasing rates of a series of FK409 derivatives, of which chain lengths or substituents were systematically modified, in sodium-phosphate buffer solution at pH 7.4. Furthermore, we studied their in vitro antiplatelet and vasorelaxant effects to evaluate relationships between spontaneous NO-releasing activities of FK409 analogs and their biological activities. FK409 derivatives were found to possess different spontaneous NO-releasing rates and biological activities according to their structural modification. In addition, these studies revealed a close correlation between NO-releasing rates of FK409 derivatives and their in vitro antiplatelet activities in human platelet-rich plasma, whereas the in vitro vasorelaxant activities of these compounds in isolated rat aorta did not correlate with the rates of NO liberation. The vasorelaxant effects were supposed to be affected by the structural properties of FK409 derivatives as well as their NO-releasing abilities.     

Optimal software release scheduling based on artificial neural networks

The determination of the optimal software release schedule plays an important role in supplying sufficiently reliable software products to actual market or users. In the existing methods, the optimal software release schedule was determined by assuming the stochastic and/or statistical model called software reliability growth model. In this paper, we propose a new method to estimate the optimal software release timing which minimizes the relevant cost criterion via artificial neural networks. Recently, artificial neural networks are actively studied with many practical applications and are applied to assess the software product reliability. First, we interpret the underlying cost minimization problem as a graphical one and show that it can be reduced to a simple time series forecasting problem. Secondly, artificial neural networks are used to estimate the fault-detection time in future. In numerical examples with actual field data, we compare the new method based on the neural networks with existing parametric methods using some software reliability growth models and illustrate its benefit in terms of predictive performance. A comprehensive bibliography on the software release problem is presented. This revised version was published online in June 2006 with corrections to the Cover Date.     

Evaluation of liposomal behavior in the gastrointestinal tract after oral administration using real-time in vivo imaging

Liposomes are regarded as promising drug carriers for enhancing the pharmacological effects of poorly absorbed drugs, such as peptides, following oral administration. Liposomal surface modifications by mucoadhesive polymers could improve drug absorption through interactions with the mucus layer. The main purpose of this study was to establish a method of monitoring the behavior of liposomes within the body after oral administration, particularly in the gastrointestinal (GI) tract, using a real-time in vivo imaging system (IVIS) to elucidate the behavior of surface-modified liposomes. Indocyanine green (ICG) was used as a near-infrared dye to label chitosan (CS) or glycol CS (GCS)-modified liposomes, and to observe the dynamic behavior of the liposomes in rats by noninvasive IVIS after oral administration. First, we validated IVIS results of the rat abdomens by comparing them to quantitative measurements of ICG fluorescence intensity in tissue homogenates. Nano-sized small unilamellar vesicles were retained longer than micro-sized multilamellar vesicles in the GI tract. Furthermore, surface-modified liposomes showed longer-term retention in the GI tract than unmodified liposomes in fasted rats. Moreover, surface modification by CS or GCS effectively prevented the excretion of liposomes from the GI tract and prolonged retention in fed rats.     

Male-Released Sex Pheromone of the Stink Bug Piezodorus hybneri

Male-released semiochemicals of the stink bug Piezodorus hybneri (Heteroptera: Pentatomidae) elicit attraction of male and female bugs and homosexual behavior in males. Three active components were isolated from the airborne volatiles of males by flash chromatography, with the activity monitored by GC-EAD and behavioral bioassay. The pheromone system was characterized as a mixture of -sesquiphellandrene, (R)-15-hexadecanolide, and methyl 8-(Z)-hexadecenoate (ratio: 10:4:1), and the activity of the semiochemicals was assessed with authentic samples. Enantiomerically pure samples of the R and S macrolactones were obtained by Yamaguchi's and Mitsunobu's macrolactonization of a key intermediate, (R)-15-hydroxyhexadecanoic acid. The nonnatural S stereoisomer was neither a beneficial nor a behavioral antagonist. Individual constituents or binary mixtures were active, but the optimal male response was elicited only by the full mixture. Behavioral observation and the fact that the onset of pheromone production is coincident with ovarian development strongly suggest that these semiochemicals are, in fact, sex pheromones.