Development of a new aortoscope system for the use of endovascular intervention.

"Balloon aortoscopy" is a technique for viewing inner wall of aorta and used in clinics. By this method, endoluminal aortic surface could be clearly monitored, however, during this period, the aortic blood flow is blocked off by the inflated balloon. To solve this clinical problem, we have been developing a prototype aortoscope system without blocking off aortic flow aiming for the use of an assistive technique for endovascular interventions such as stent-graft placement for aortic aneurysm and have been evaluating through in vitro and in vivo tests. The technique introduced for this purpose was the use of intermittent and instantaneous saline jet controlled by a high-speed electromagnetic valve synchronized to heart beat (diastolic phase). In the previous study, we designed an endoscope with two channels (one for saline discharge and the other for forceps insertion), and confirmed the validity of this method by in vitro and in vivo tests. Based on these findings, in this study, we have newly designed a conventional and low price endoscope system aiming for wide clinical use. From the results of in vitro tests using a mock circulation system, it was confirmed that the newly designed system was capable of visualizing a target installed on an inner surface of the mock system suggesting an availability of the system for an aortoscope without blocking off aortic flow.

A new proposal of tailored bioinstrumentation using rapid prototyping and three-dimensional CAD--first trial to develop individually designed cuff-units for continuous blood pressure measurement.

The concept of tailored bioinstrumentation using rapid prototyping and three-dimensional CAD (3D-CAD) was proposed. This concept is to make individually designed and fabricated sensor unit to attach human body. Within the proposed concept, cuff-units for continuous blood pressure measurement were individually designed using 3D-CAD and fabricated automatically. As the result, blood pressure wave forms can be obtained using the finally developed cuff units. Using rapid prototyping device, the design and fabrication process were accelerated without any artisan-like high skilled persons.

Feasibility study on driver's stress detection from differential skin temperature measurement.

Prolonged monotonous driving may lower a driver's awareness level as well as increasing their stress level due to the compulsion to maintain safe driving, which may result in an increased risk of a traffic accident. There is therefore an opportunity for technological assessment of driver physiological status to be applied in-car, hopefully reducing the incidence of potentially dangerous situations. As part of our long-term aim to develop such a system, we describe here the investigation of differential skin temperature measurement as a possible marker of a driver's stress level. In this study, healthy male (n=18) & female (n=7) subjects were investigated under environment-controlled conditions, whilst being subjected to simulated monotonous travel at constant speed on a test-course. We acquired physiological variables, including facial skin temperature which consists of truncal and peripheral skin temperatures (Ts) using thermography, beat-by-beat blood pressure (BP), cardiac output (CO), total peripheral resistance (TPR), and normalized pulse volume (NPV) used as an indicator of local peripheral vascular tone. We then investigated the driver's reactivity in terms of skin temperatures with this background of cardiovascular haemodynamics. We found that the simulated monotonous driving produced a gradual drop in peripheral Ts following the driving stress, which, through interpretation of the TPR and NPV recordings, could be explained by peripheral sympathetic activation. On the other hand, the truncal Ts was not influenced by the stress. These findings lead us to suggest that truncal-peripheral differential Ts could be used as a possible index indicative of the driver's stress.

A preliminary study on driver's stress index using a new method based on differential skin temperature measurement.

Prolonged periods of driving in monotonous situations may lower a driver's activation state as well as increasing their stress level due to the compulsion to maintain safe driving, which may result in an increased risk of a traffic accident. There is therefore an opportunity for technological assessment of driver physiological status to be applied in-car, hopefully reducing the incidence of potentially dangerous situations. As part of our long-term aim to develop such a system, we describe here the investigation of differential skin temperature measurement as a possible marker of a driver's stress level. 10 healthy male subjects were studied, under environment-controlled conditions, whilst being subjected to simulated monotonous travel at constant speed on a test-course. We acquired measurements of relevant physiological variables, including truncal and peripheral skin temperatures (T(s)), beat-by-beat blood pressure (BP), cardiac output (CO), total peripheral resistance (TPR), and normalized pulse volume (NPV) used as an indicator of local peripheral vascular tone. We then investigated the driver's reactivity in terms of cardiovascular haemodynamics and skin temperatures. We found that the simulated monotonous driving produced a gradual drop in peripheral T(s) following the driving stress, which, through interpretation of the TPR and NPV recordings, could be explained by peripheral sympathetic activation. On the other hand, the truncal T(s) was not influenced by the stress. These findings lead us to suggest that truncal-peripheral differential T(s) might be used as a possible index indicative of the driver's stress.

A new non-invasive method for measuring blood glucose using instantaneous differential near infrared spectrophotometry.

We describe further development of a novel method for non-invasive measurement of blood glucose concentration (BGL), named Pulse Glucometry, based on differential near infrared spectrophotometry. Sequential temporal differences of infrared transmittance spectra from the radiation intensity (I(lambda)) emerging from a fingertip containing an arterial pulse component (DeltaI(lambda)) are analysed. To perform the measurements we developed a new high-speed spectrophotometer, covering the wavelength range from 900 to 1700 nm, scanning at a maximum spectral rate of 1800 spectra/s, with a minimum exposure time of 20 micros. Spectra related only to the pulsatile blood component are derived, thus minimising influences of basal components such as resting blood volume, skin, muscle and bone. We have now improved the performance of the spectrophotometer and in the present paper we describe new in vivo measurements carried out in 23 healthy volunteers undergoing glucose tolerance tests. Blood samples were collected from the cephalic vein simultaneously with radiation intensity measurements in the fingertip every 10 min before and after oral administration of glucose solution for 120 min. BGL values were then predicted using a PLS calibration model and compared with blood values determined by colorimetric assay. The precision and accuracy of the non-invasive determinations are encouraging.

Hemodynamic responses during simulated automobile driving in a monotonous situation.

Long hours of automobile driving under monotonous situations may cause the lowering of what we term a driver's activation state (DAS) or in other words the production of drowsiness, resulting in an increased risk of a traffic accident. There is therefore a need to create a newly advanced system focused on the DAS in-car, hopefully thus avoiding potentially dangerous situations. In order to develop such a system as a final goal, we have firstly set out to acquire such cardiovascular variables as beat-by-beat blood pressure (BP), RR interval from ECG and normalized pulse volume (NPV) used as a peripheral vascular tone of alpha-adrenergic sympathetic activity, during presentation to the driver of a screen movie simulating monotonous travel at constant speed on a test-course. Subsequently, we have investigated the reactivity in terms of the driver's cardiovascular hemodynamics. Through the successful monitoring of cardiovascular parameters during the movie presentation obtained in 11 healthy male subjects, the following results were obtained: The monotonous driving produces a statistically significant gradual rise in BP following drowsiness, which could be explained by enhancement of sympathetic activity using a time-frequency analysis of BP and RR. This finding strongly indicates that continuous driving in such monotonous situations can make a driver considerably stressful and thus may cause a gradual increase in BP, and that this gradual BP increase may be used as a possible index relevant to the DAS. This finding was also confirmed by the analysis of NPV, suggesting that the gradual increase in BP during the monotonous driving would be rather caused by a regulation of peripheral vasomotor constriction.

Nitric oxide contribution to vascular wall oxygen consumption in arterioles.

To study the role of nitric oxide (NO) in regulating oxygen consumption by vessel walls, the oxygen consumption rate of arteriolar walls in rat cremaster muscle was measured in vivo during flow-induced vasodilation and after inhibiting NO synthesis. The oxygen consumption rate of arteriolar was calculated based on the intra- and peri-vascular oxygen tension (P0(2)) values measured by phosphorescence quenching laser microscopy. The peri-vascular PO(2) value of the arterioles during vasodilation was significantly higher than under control conditions, although the intravascular PO(2) values under both conditions were approximately the same. On the other hand, inhibition of NO synthesis caused a significant decrease in both the intra- and peri-vascular P0(2) values of the arterioles. The inhibition of NO synthesis increased the oxygen consumption rate of the walls by 42%, whereas enhancement of flow-induced NO release decreased it by 34%. These results suggest that NO plays an important role not only as a regulator of peripheral vascular tone, but also as a modulator of tissue oxygen consumption by reducing oxygen consumption by vessel walls.

Assessing the Effectiveness of Increased FIO2for Enhancing Driver's Activation State Using Simulated Monotonous Driving.

Lowering of what we term a driver's Activation State (AS) during monotonous driving conditions may increase the risk of an accident. To develop an in-car environment that allows active driving - "Biofee dforward System" - we have investigated the effects of applying a stimulus of increased inspired oxygen fraction (FIO2) supply on a driver's AS, using simulated monotonous driving. We used our previously substantiated index of As derived from beat-by-beat blood pressure (BP) response following an electrical stimulus. We have made physiological measurements including BP and found that the increased FIO2stimulus is effective in enhancing the AS. This finding was also confirmed in terms of the autonomic activity balance as well as the lengthening in time for active, safer, driving.

Physiological investigation of automobile driver's activation index using simulated monotonous driving.

Monotonous automobile operation in our daily life may cause the lowering of what might be termed an activation state of the human body, resulting in an increased risk of an accident. We therefore propose to create a more suitable environment in-car so as to allow active operation of the vehicle, hopefully thus avoiding potentially dangerous situations during driving. In order to develop such an activation method as a final goal, we have firstly focused on the acquisition of physiological variables, including cardiovascular parameters, during presentation to the driver of a monotonous screen image, simulating autonomous travel of constant-speed on a motorway. Subsequently, we investigated the derivation of a driver's activation index. During the screen image presentation, a momentary electrical stimulation of about 1 second duration was involuntarily applied to a subject's shoulder to obtain a physiological response. We have successfully monitored various physiological variables during the image presentation, and results suggest that a peculiar pattern in the beat-by-beat change of blood pressure in response to the involuntary stimulus may be an appropriate, and feasible, index relevant to activation state.

Association between nasal allergy and a coding variant of the Fc epsilon RI beta gene Glu237Gly in a Japanese population.

The gene for the beta-chain of the high-affinity receptor for IgE (Fc epsilon RI beta) has been proposed as a candidate gene for atopy. A coding variant Glu237Gly has been studied in various populations with asthma and atopy, and the results were controversial for association of the variant with atopy/asthma. Because nasal allergy is a more common atopic disease and shows less remission than asthma, we analyzed whether the Glu237Gly variant is correlated with nasal allergy. The study enrolled 233 patients with nasal allergy and 100 control subjects. Further, three subgroups were selected: patients with perennial nasal allergy (n=149), Japanese cedar pollinosis (n=189), and allergy to multiple allergens (n=45). The allele frequency of Gly237 in the controls and patients was 0.14 and 0.20, and the frequency of Gly237-positive subjects was 0.23 and 0.356, respectively. There was a significant association between Gly237-positivity and nasal allergy, perennial nasal allergy, Japanese cedar pollinosis, and allergy to multiple allergens. Among all 333 subjects we observed a significant relationship between Gly237 and elevated levels of serum total IgE (>250 IU/ml) and very high IgE (>1000 IU/ml). Among patients positive for a specific IgE, Gly237 was significantly associated with high IgE for house dust, mite, and Japanese cedar pollen. These results suggest that the Glu237Gly variant of the Fc epsilon RI beta gene is involved in the development of nasal allergy through the process for the production of both specific and nonspecific IgE antibodies.

Comparative role of peptide leukotrienes and histamine in the development of nasal mucosal swelling in nasal allergy.

To evaluate the importance of histamine and peptide leukotrienes (LTs) in the development of nasal mucosal swelling in nasal allergy, H1 receptor antagonist (mequitazine, 6 mg, in 2 divided doses, Rhône-Poulenc Rorer, France) and LT receptor antagonist (ONO-1078, pranlukast, 450 mg, in 2 divided doses, Ono Pharmaceutical Co, Ltd, Osaka) were administered orally for 7 days to 16 subjects with perennial nasal allergy to house dust mites, and the effects of receptor blockers of these chemical mediators on the effective cross-sectional area of the nasal cavity (ECA) at rest, at exercise load, at antigen challenge, and at exercise load following antigen challenge were studied. After the administration of H1 receptor antagonist, ECAs at all measurement points slightly increased, but no statistical significance was observed. On the other hand, LT receptor antagonist inhibited ECAs 10 minutes after exercise load, just after the end of antigen challenge, 10 minutes later, and at exercise load following antigen challenge with statistical significance. These results suggest that LTs are involved markedly, and histamine slightly, in the development of nasal mucosal swelling in nasal allergy.

The effect of ramatroban (BAY u 3405), a thromboxane A2 receptor antagonist, on nasal cavity volume and minimum cross-sectional area and nasal mucosal hemodynamics after nasal mucosal allergen challenge in patients with perennial allergic rhinitis.

The thromboxane A2 receptor antagonist, ramatroban (BAY u 3405), was orally administered for 4 weeks at a daily dose of 150 mg (b.i.d.) to 10 patients with perennial allergic rhinitis who had a positive reaction to house dust challenge on nasal mucosa. Nasal cavity volume and minimum cross-sectional area were measured, and changes in nasal mucosal swelling were determined following allergen challenge with house dust. The influence on nasal mucosal hemodynamics was also investigated. Nasal cavity volume and minimum cross-sectional area were measured by acoustic rhinometry, and blood flow in the nasal mucosa was measured by laser Doppler flowmetry. Percent changes in values from baseline nasal cavity volume were significantly decreased by allergen challenge before ramatroban administration, but no significant decrease was noted after ramatroban administration. Similarly, percent changes in values from baseline nasal cavity minimum cross-sectional area were significantly decreased by allergen challenge before administration of ramatroban, but not after administration. Percent changes in values from baseline nasal mucosal hemodynamics were significantly increased by allergen challenge both before and after ramatroban administration, which thus had no effect on mucosal hemodynamics. These findings suggest that ramatroban might inhibit the increase in nasal mucosal swelling but has no effect on nasal mucosal hemodynamics.

Mode of action of a topical steroid on immediate phase reaction after antigen challenge and nonspecific nasal hyperreactivity in nasal allergy.

This study compared the effects of 2-week administration of a topical steroid (fluticasone propionate [FP] 100 micrograms twice daily) with placebo in 28 patients with perennial nasal allergy who were allergic to house dust and mites in a double-blind randomized study. The number of inflammatory cells and decidual epithelial cells and concentrations of tryptase and eosinophil cationic protein in nasal lavages, and reactivity of the nasal mucosa to histamine and to antigen were investigated. The topical steroid, FP, significantly inhibited all of these assessments. The degree of improvement of nasal reactivity to histamine significantly correlated with the degree of decrease in eosinophil cationic protein levels.

[Inhibitory activity of mite IgG4, antibody on antigen-induced histamine release from human peripheral blood leukocytes].

Several reports have yielded conflicting results on the role of IgG4 antibody on the surfaces of target cells in immediate type allergy. This study was performed to elucidate whether IgG4 antibody inhibits IgE-mediated histamine release from target cells after antigenic stimulation, and whether it has reaginic activity. Serum was obtained from patients with nasal allergy receiving specific immunotherapy for housedust and mites. IgE and IgG4 were enriched affinity chromatographically using monoclonal antibodies to IgE and IgG4, respectively, from the pooled sera. Both fraction revealed high antibody activity to Dermatophagoides Farinae antigen. Peripheral blood leukocytes from three non-allergic donors were passively sensitized with 100 or 300 micrograms of IgG4 according to the method of Levy and Osler with a slight modification. Minimal or no histamine release was observed from leukocytes after challenge with both mite antigen and anti-IgG4 monoclonal antibodies. Furthermore, to investigate the reaginic activity of IgG4, leukocytes from patients with nasal allergy were stimulated with anti-IgG4 antibodies. The leukocytes of only three out of twenty patients released up to 10% histamine regardless of the IgG4 concentration, while the other patients' leukocytes released minimal amounts of histamine. Two of the three above-mentioned non-allergic donors were passively sensitized with 100 or 300 micrograms of IgG4 either one hour after sensitization with 100 ngs of IgE or simultaneously with the same amount of IgE. After sensitization with 100 ngs of IgE, one showed high-grade histamine release after challenge with 0.5 micrograms/ml mite antigen and the other showed middle-grade release with 0.1 micrograms/ml mite. With the presence of 300 micrograms of IgG4, histamine release was significantly inhibited in both donors regardless of the manner of sensitization.(ABSTRACT TRUNCATED AT 250 WORDS)

[Clinical statistics of the patients admitted to the Department of Urology Shizuoka Red Cross Hospital between 1981 and 1990].

A statistic survey was made on the patients, diseases and operations experienced at the Urological ward of Shizuoka Red Cross Hospital between 1981 and 1991. The total number of inpatients was 2,830 and the male to female ratio was 3.5 to 1. The most frequent diseases among the inpatients were obstructive uropathy (25.5%), malignant neoplasia (23.7%), non-specific infection (16.4%) urolithiasis (16.1%). The number of operations was 1922. Endoscopic surgery was the most frequent form of operation (55.2%).

[Hemangiopericytoma of the prostate: a case report].

A case of hemangiopericytoma arising in the prostate is presented. The patient, a 67-year-old male, was admitted to the hospital for difficulty in urination and underwent transurethral resection of the prostate. The pathological diagnosis was "well-differentiated adenocarcinoma and focal hemangiopericytoma". To the best of our knowledge, the only four cases of hemangiopericytoma of the prostate have been reported in the English literature so far and none in the Japanese literature.