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Notes: Summary We have analysed the pharmacokinetics ofα-human atrial natriuretic polypeptide (α-hANP) in healthy subjects, using a two-compartment open model following bolus intravenous injection. The plasma half-times for the fast and slow components were 1.7±0.07 min and 13.3±1.69 min respectively. V1 (the volume of the central compartment), Vz (volume of distribution) and Vss (volume of distribution at steady-state) were 5370±855 ml (89.5±14.3 ml·kg−1), 32000±4620 ml (533±77.0 ml·kg−1), and 11900±1530 ml (198±25.5 ml·kg−1) respectively. The mean plasma clearance was 1520±121 ml·min−1 (25.4±2.0 ml·min−1·kg−1.

Notes: Formation of a straight helical magnetic field is attempted by using ferromagnetic material. A shaped ferromagnetic cylinder, which modifies an external uniform magnetic field, is demonstrated to realize an l=3 helical magnetic field that is suitable for plasma experiments. The measured values for the angle of rotational transform and shear length agree with the predictions within a factor of 2, which is calculated without taking account of the self-demagnetization. This indicates that a rough configuration of magnetic field can be obtained even if the self-demagnetization is not known accurately. It is also suggested that this method is widely applicable to the formation of other complicated configurations of magnetic field.

Notes: A superconducting electron storage ring fully dedicated to x-ray lithography has been developed. It has a racetrack shape, consisting of two superconducting bending magnets, other normal conducting multipole magnets, rf system, vacuum system, and beam monitoring systems. The storage ring circumference is 16.8 m. The critical wavelength (λc) is 17.3 A(ring). The beam size (σ) at every synchrotron radiation source point is less than 1 mm. This machine employs the energy-boost-in-the-ring scheme; electrons are injected at around 15 MeV and then accelerated to 600 MeV in the ring. The injector is a newly developed linear accelerator with an energy compression system. Higher-energy injection is also available.

Notes: A normal-conducting accelerating ring (NAR) has been constructed with a Chasman–Green-type lattice. The NAR has two basic aims. One aim is to prove the feasibility of the novel accelerating and storage scheme, in which the NAR accelerates the injected 15-MeV electrons to the final energy of 800 MeV, and directly stores them. The other aim is to make the NAR a multipurpose ring. That is, it acts as a booster for the superconducting storage ring, and it supplies the synchrotron radiation with the critical wavelength, 20.2 A. To achieve a high beam current, particular considerations have been taken with injection, rf system, magnetic field tracking, and vacuum formation. The NAR has experienced acceleration and storage at the final energy, 800 MeV. The initial beam current is about 20 mA in the 800 MeV storage mode.

Notes: The aim of this study is to visualize the coronary artery with the intravenus injection of contrast media. We propose a method of rapid and successive acquisition of two-dimensional images in a digital processing system which uses a pair of video cameras, a shutter operation, and a beam-splitting apparatus. A prototype of the high-speed acquisition system was constructed. The two-monochromatic video-camera method was very suitable for quick acquisition. Electro-optical shutters (PLZT) were found practical with respect to the dynamic range and response time. The field blanking method was essential for the data acquisition.

Notes: Ischemic heart disease is one of the most popular and lethal diseases for aged peoples in the world, and is usually diagnosed by transarterial selective coronary arteriography. However, it is rather invasive and somewhat dangerous, so that the selective coronary arteriography is not feasible for prospective screening of coronary occlusive heart disease. Conventional digital subtraction angiography (DSA) is widely known as a relatively noninvasive and useful technique is making a diagnosis of arterial occlusive disease, especially in making the diagnosis of ischemic heart disease. Conventional intravenous subtraction angiography by temporal subtraction, however, has several problems when applying to the moving objects. Digital subtraction method using high-speed switching above and below the K edge could be the ideal approach to this solution. We intend to make a synchrotron radiation digital K-edge subtraction angiography in the above policy, and to apply it to the human coronary ischemic disease on an outpatient basis. The principles and experimental systems have already been described in detail by our coworkers.Our prototype experimental system is situated at the AR (accumulation ring) for TRISTAN project of high energy physics. The available beam size is 70 mm by 120 mm. The electron energy of AR is 6.5 GeV and average beam current is approximately 10 mA. This paper will show the animal experiments of our K-edge subtraction system, and discuss some problems and technical difficulties. Three dogs, weighing approximately 15 kg, were examined to evaluate the ability of our prototype synchrotron radiation DSA unit, that we are now constructing. The dogs were anaesthetized with pentobarbital sodium, intravenously (30 mg/kg). Six french-sized (1.52 mm i.d.) pigtail catheter with multiple side holes were introduced via the right femoral vein into the right atrium by the cutdown technique under conventional x-ray fluoroscopic control. Respiration of the dogs was controlled by a mechanical ventilator. The respirations were held for several seconds when taking the images. Approximately 10 to 15 ml of 76% water soluble iodinated contrast medium (Urografin 76, Schering) was injected by an automatic electronic injector at the rate of approximately 10 ml/s. Three or four times injections were done so as not to exceed the normal renal excretion threshold.Intravenous drip infusion of saline (500 ml/2 h) was used to accelerate the washout of contrast medium via renal system. One hundred micrograms of nitroglycerin were administered, intravenously to dilate the coronary arteries, approximately 3 min prior to contrast injection. Sometimes we used 0.1 mg/kg of beta blockage agent (Propranorol) to decrease the heart rate. Subsequently, the heart rate of the dogs was decreased from approximately 200/s to 100/s. These techniques are commonly used in human examinations. Materials are positioned at left anterior oblique view. The sequential images are now detected above the iodine K edge by an image intensifier (RTP 9240F, Toshiba) and recorded at high signal-to-noise ratio analog video recording system (C1900, Hamamatsu Photonics, S/N 45 dB). Proximal coronary arteries are well visualized, however the distal portions are unsatisfactory, because of the overlapping of the contrast-filled dense heart chambers and pulmonary vessels. Bolus injection of contrast medium is also necessary, unless overlapping is inevitable, so are the same in conventional intravenous DSA. The energy above and below the K edge is now changed by tilting the angle of crystal, mechanically, so it has not sufficient speed to subtract the moving material. Real time A/D converter and frame buffering memories have not been available, until now. Even though there are many limitations in the hardware and many problems to overcome, our preliminary animal experiments allow us to have high expectations.

Notes: Sonic extract (SE) from periodontopathic bacteria were studied for their effects on the immune response and adjuvanticity. The preparations of SE from A. actinomycetemcomitans, B. intermedius and B. gingivalis were found to have strong immunomodulating activity against the antigen itself and also sheep erythrocytes (SRBC) in in vivo experiments using C3H/HeN mice. All the SE enhanced the immune response to antigen and SRBC at low concentration. A strong immuno suppressive effect, however, was found at high concentrations of A. actinomycetemcomitans and B. intermedius but not of B. gingivalis. Moreover, these immunosuppressive effects were enhanced by the 3-day-prior injection to SRBC even at low concentrations, including that of B. gingivalis. The suppressive effect of SE from A. actinomycetemcomitans was dependent on the protein fraction in the SE tested, because suppressed anti-SRBC immune response was restored by pronase treatment or heating. Failure to recover immune response, found in a similar experiment using Bacteroides intermedius, indicated that its suppressive effect was due to a heat-stable and pronase-resistant substance. These findings, along with the data presented in this paper, support the hypothesis that patients who harbor these bacteria could suffer systemic immune suppression not only from the initial periodontopathic bacteria but also from secondary infecting bacteria. These suppressive effects may also enhance the pathogenicity of other opportunistic organisms in the gingival crevice.

Notes: Abstract This paper deals with a new anti-fouling method by hydrogen peroxide with ferrous ion for a marine cooling water system. Emphasis is on macrofouling which decreased less than 10% of the amount of the control after the chemical treatment of seawater. The duration of the chemical effectiveness was examined with 60-m unheated model channels from April to July 1986. Since hydrogen peroxide and ferrous ion were reduced by 20% and 40%, respectively, within 10 min, the retention period of seawater in the system is necessary to extrapolate test results from pilot studies to actual application. It is suggested that the active oxygen radical produced in seawater from the reaction of hydrogen peroxide with ferrous ion, affects attachment and subsequent growth of sedentary larvae of marine animals. The results indicated that for barnacles, the chemicals did not disturb the settling behavior of the cyprid, but inhibited the growth of the young after settling. For mussels, on the other hand, which were collected offshore of Tokushima Prefecture from March to June 1986, the chemicals hampered the pelagic pediveliger or plantigrade substantially during the exploratory phase.