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For the determination of trace amounts of oxygen in iron and steel, a pre-treatment procedure was developed using glow discharge. This permits to remove surface oxygen contaminations, which cannot be eliminated by conventional pre-treatment methods such as electropolishing. The analytical values of oxygen obtained after the glow discharge pre-treatment were approximately 1–2 μg/g lower than those without pre-treatment. This difference is consistent with the oxygen surface contamination determined by surface analysis and charged particle activation analysis.

Objectivesto analyse the relationship between vascular trauma and associated injuries to intra-thoracic and abdominal organs caused by traffic accidents. Designretrospective study in a university hospital.Materials and methodswe investigated 458 consecutive patients who were admitted with blunt thoracic and/or abdominal trauma caused by road traffic accidents between 1986 and 1999. Vascular trauma was encountered in 54 patients (12%).Resultsthe injured vessels were located in the abdomen in 45 patients and in the chest in nine patients. Mesenteric vessels were the most frequently injured vessels (33/45) in the abdomen, while the aorta and major vessels were most frequently injured (9/9) in the chest. Injury to the large/small intestine was often associated with mesenteric vessel injury (26/27). In the 190 patients with blunt abdominal organ injury, the frequency of mesenteric vessel injury was also highest, regardless of the injured organ. Vascular reconstruction was necessary only in one of 51 patients who underwent operation.Conclusionsour results demonstrate that the mesenteric vessels are susceptible to blunt thoracic and abdominal trauma in road traffic accidents. Vascular reconstruction may be indicated for selected patients as long as the injuries to hollow organs are assessed carefully because of their strong association with vascular injury.

Objective: To establish the usefulness of currently available tests of coagulation defects for predicting symptomatic pulmonary embolism (PE) in patients with lower extremity deep vein thrombosis (DVT).Methods: Between 1980 and 1996, 294 patients with DVT were followed for a mean period of 7.9 years. The coagulation defects included low activity of antithrom-bin III, protein C, protein S or plasminogen, and positivity for lupus anticoagulant or anticardiolipin antibody. The influences of these coagulation abnorm-alities on PE incidence were analysed, using a Cox regression hazards model.Results: Coagulation defects were found to be an important variable predicting PE (risk ratio = 7.272). ‘PE-free survival’ in patients with no coagulation defect was significantly longer than that in patients with one or more of these defects (p= 0.0001). The sensitivity of coagulation tests for predicting PE was only 47% despite the negative predictive value of 93%.Conclusions: Determining these defects has limited usefulness in identifying patients who would be appropriate candidates for intensive anticoagulation therapy.

We have studied the effects of three imidazole derivatives, clotrimazole (CLO), ketoconazole (KET) and miconazole (MIC) on the liver microsomal diazepam (DZ) metabolism. In in vitro experiments using rats and human liver microsomes, significant inhibition of CYP3A in terms of DZ-3-hydroxylase activity was observed. The inhibition of DZ metabolism was seen 1 h after CLO dosing. On the other hand, the induction of certain cytochrome P450 (CYP) isozymes was observed in in vivo studies 24 h after dosing. That is, CYP1A, CYP2B and CYP3A2, but not CYP2E, were observed 24 h after CLO or KET or MIC treatment. Under these conditions, CLO was the most potent inducer of CYP3A and MIC was a more potent inducer of CYP1A and CYP2B. KET induced CYP1A and CYP2B whereas the inducibility of KET was less than those of CLO and MIC. All of the imidazole derivatives tested here showed significant inhibition of CYP isozymes which overcame the induction of the CYP isozymes by those drugs in the data of Western blot analysis.

Potential interethnic differences in drug disposition and effects between Japanese and white subjects hamper the registration in Japan of medications already used in Western countries. This double‐blind, placebo‐controlled, crossover study was conducted to compare the pharmacodynamics and pharmacokinetics of a single oral dose of nitrazepam (5 mg) in age‐ and sex‐matched Japanese (n = 8) and white (n = 8) healthy volunteers. The study was performed in centers in Japan and the Netherlands using the same methods and study design. Subjects were individually matched for gender, age, and body stature. Drug effects were measured by means of saccadic and smooth pursuit eye movements and visual analog lines obtained from the scales of Bond and Lader. There were no pharmacokinetic differences between the Japanese and white subjects. Clearance of nitrazepam was 0.91 ± 0.165 mL/min/kg and 1.17 ± 0.492 mL/min/kg, and half‐life (t1/2) was 22.1 ± 4.96 hours and 21.5 ± 7.51 hours for the Japanese and European groups, respectively. Pharmacokinetic parameters showed no significant correlation with age, height, or weight. The average time‐effect curves for the different parameters were comparable between groups. Compared with placebo, both groups showed similar significant reductions in average peak velocity and increases in saccadic inaccuracy and reaction time. Visual analog scores showed clear sedation in the white subjects, but insignificant effects in the Japanese subjects. Smooth pursuit did not change significantly in either group. Slope and intercept of the concentration‐effect relationships for saccadic peak velocity showed considerable intersubject variability, but no clear differences between groups. The pharmacokinetics and pharmacodynamics of nitrazepam were similar in matched healthy Japanese and white subjects. Interethnic comparative studies are feasible, and provide meaningful information about potential racial differences in disposition and action of drugs. Such studies can form a rational basis for comparative clinical trials.

Lipid peroxidation in aliquots of bovine retina (without rod outer segments, ROS), purified ROS and retinal pigment epithelium (RPE) was initiated with 5 mMferric iron and 80 mMADP. After 30 min of oxidation at 37°C, the concentration of thiobarbituric-acid-reacting substances (TBARS) which approximates lipid hydroperoxide (LHP), increased in the ROS from 2.0 ± 3.6 to 90.2 ± 34.5 nmol malondialdehyde (MDA)/mg protein and in the RPE from 0.54 ± 0.2 to 51.5 ± 15.8 nmol MDA/mg protein. Sixteen lipid and aqueous antioxidants (AOX) from natural or synthetic sources, including five flavonoids, were evaluated for their ability to inhibit the oxidative reaction. Palm-oil-derived vitamin E showed significant protection in retina, ROS and RPE (64, 68 and 74%), respectively. Of the flavonoids tested, good protection in the retina was found at 10–5Mfor epigallocatechin gallate (50%) and at 50 ng/ml for pycnogenol (61%) and catechin (52%). When catechin and palm oil vitamin E, catechin and coenzyme Q10 or coenzyme Q10 and pycnogenol were combined, the individual effect was enhanced. TBARS as an indirect measure of LHP level and hemoglobin-methylene blue determination for direct LHP were used as alternative end-point determinations of lipid peroxidation. These measure different aspects of AOX reactions. The results demonstrate the usefulness of an in vitro model system that can rapidly and accurately determine the capacity of a single AOX against lipid peroxidation or be used to show synergistic efficacy.

A recombinant (H1N2, formerly Hsw1N2), A/swine/Ehime/1/80 was found to possess antigenic, biological and genomic characteristics different from those of a previous A/swine/Kanagawa/2/78 (H1N2) strain (22). Five monoclonal antibodies to A/NJ/8/76 definitely differentiated the hemagglutinin molecules of the former virus from the latter, showing that these viruses differed, at least, at two antigenic determinants. Neuraminidase-inhibition tests with monoclonal antibodies to different H2N2 and H3N2 viruses revealed that the A/swine/Ehime/1/80 strain contained a neuraminidase very similar to that of the late human Asian (H2N2) and the earliest Hong Kong (H3N2) viruses. Growth comparison of swine and human isolates indicated that A/swine/Ehime/1/80 and A/swine/Shizuoka/1/78 (H1N1) failed to grow at 42°C, while A/swine/Kanagawa/2/78 and its possible parental virus, A/swine/Kanagawa/4/78 (H1N1) replicated efficiently at this stringent temperature. These results revealed that the viruses having growth characteristics similar to those of avian influenza virus were present in the swine population. RNA analysis by oligonucleotide mapping suggested that A/swine/Ehime/1/80 may be a recombinant between A/swine/Shizuoka/1/78-like and A/Aichi/2/68 (H3N2)-like viruses. To further determine the gene constellation of this recombinant virus, DNA-RNA hybridization was performed by using DNA segments complementary for swine (H1N1) virus RNA and the entire RNAs of three viruses. The molecular hybridization could define the genomic composition of the recombinant, indicating that only the neuraminidase gene of this virus is derived from the earliest Hong Kong (H3N2)-like virus and remaining seven genes from swine (H1N1) virus.

Spontaneous dissection of the splanchnic arteries is rare and reportedly carries a high risk of mortality. Two cases with spontaneous dissection of the main trunk of the superior mesenteric artery followed by a self-limited clinical course are presented. Current management strategies, including bypass operation, patch angioplasty, and conservative treatments, are discussed. Emphasis is placed on the role of nonsurgical management with careful follow-up with the use of new technologies such as duplex and computed tomography scanning. (J Vasc Surg 1998;27:776-9.)

Purpose: Patients with chronic venous insufficiency (CVI) were evaluated from the aspect of ambulatory venous function using near-infrared spectroscopy (NIRS). Methods: Seventy-two primary varicose veins of 59 patients (varicose group) and 20 normal limbs of 13 volunteers (normal group) were studied. The affected limbs of the patients were divided into three groups according to the classification advocated by an International Consensus Committee in 1995: mild CVI with class 2 or 3 (50 limbs); moderate CVI with class 4 (11 limbs); and severe CVI with class 5 or 6 ( 11 limbs). All of the patients underwent a treadmill walking test, during which NIRS was applied. Oxygenated hemoglobin (OxyHb) and deoxygenated hemoglobin (DeoHb) were continuously measured by NIRS during exercise. The ambulatory venous retention index (AVRI) obtained from serial changes in DeoHb was assessed comparatively in the four groups (normal and mild to severe CVI). In addition, 19 limbs in 13 patients were evaluated with air plethysmography for comparison with the data obtained by NIRS. Results: Two distinct patterns of DeoHb change were observed. During exercise, the DeoHb level decreased in the normal group as a result of calf muscle contraction, whereas in the varicose group the DeoHb level rose because of an apparent venous reflux into the calf muscles. AVRI studies demonstrated a significant difference (p < 0.0001) among groups. Although there was no apparent relationship between AVRI and ejection fraction, AVRI showed a significant correlation with the venous filling index (r = 0.61) and a weak correlation with the residual volume fraction (r = 0.41). Conclusion: NIRS is useful for accurately assessing ambulatory venous dysfunction in patients with primary varicose veins. (J Vasc Surg 1997;26:53-60.)

Objectives:: To examine the effects of the anti-angiogenic drug AGM1470 on smooth muscle cell (SMC) migration activity stimulated by endothelial cell (EC)-derived mitogen. Materials and Methods:: Study 1; EC's were cultured under pulsatile flow using MCDB151 medium. From the supernatant of these EC dishes we devised two types of conditioned medium; anti-PDGF(+) containing 10 g/ml anti-PDGF antibody, and anti-PDGF(-) containing no antibody. SMC's were cultured using both media. Study 2; EC's were cultured under the same conditions using both types of medium; MCDB151 medium containing 10 ng/ml AGM1470, and MCDB151 medium alone. After the AGM1470 concentration had been adjusted to 10 ng/ml, SMC's were cultured using each medium; AGM-exposed EC and AGM-non-exposed EC. SMC colony spreading distances were measured as an index of mitogenic activity for 4 days. Results:: Study 1; the anti-PDGF(-) group showed an apparently greater spreading distance than the anti-PDGF(+) group. Study 2; the AGM-non-exposed EC group showed a significantly greater spreading distance than the AGM-exposed EC group. However, MTT assay revealed no differences in proliferation between the two groups. Conclusion:: AGM1470 suppresses the EC production of this PDGF-like mitogen as well as SMC migration activity.

Removing the oxide film from the sample surface is an important process in analyzing trace oxygen in iron and steel. The depth profiles of oxygen on the surface after electropolishing in CH3COOH— HClO4, CrO3—H3PO4, and HCl, and chemical polishing by HF– H2O2 are investigated. The thickness of the oxide layer after electropolishing is estimated to be about 3 nm, which is approximately equivalent to 1 mass ppm oxygen. This indicates that the currently available surface polishing methods are inadequate for the analysis of mass ppm or sub-ppm oxygen levels. A surface without an oxide layer is obtained by Ar ion sputtering in a vacuum, but the oxide layer reappears within 1 min when the sample comes into contact with air.

Background: The risk factors for restenosis after angioplasty have not yet been established because of the inconsistencies among treated lesions, differences in the techniques used, and variable end points. We evaluated the predictive variables relating to postangioplasty restenosis. Methods: One hundred sixty-one transluminal balloon angioplasties were studied in 138 consecutive patients with focal iliac arterial stenosis (@?4 cm) caused by arteriosclerosis between January 1981 and December 1995. Restenosis was diagnosed on the basis of recurrent symptoms associated with an apparent drop in the ankle-brachial pressure index and angiographic visualization of restenosis. Results: Being younger than 60 years (risk ratio 2.585) and poor runoff (risk ratio 2.328) were found to be important variables predicting restenosis by the Cox regression model. The restenosis-free patency rates were significantly better in patients older than 60 years of age (p = 0.0242), with good distal runoff (p = 0.0487), and without diabetes (p = 0.0111). Conclusions: Being younger than 60 years of age and poor distal runoff are important predictors of restenosis after iliac balloon angioplasty. (Surgery 1998;123:658-65.)

Flow‐through tests are completed on a natural fracture in novaculite at temperatures of 20°C, 80°C, 120°C, and 150°C. Measurements of fluid and dissolved mass fluxes, and concurrent X‐ray CT imaging, are used to constrain the progress of mineral dissolution and its effect on transport properties. Under constant effective stress, fracture permeability decreases monotonically with an increase in temperature. Increases in temperature cause closure of the fracture, although each increment in temperature causes a successively smaller effect. The initial differential fluid pressure‐drop across the fracture increases by two orders of magnitude through the 900 h duration of the test, consistent with a reduction of an equivalent hydraulic aperture by a factor of five. Both the magnitude and rate of aperture reduction is consistent with the dissolution of stressed asperities in contact, as confirmed by the hydraulic and mass efflux data. These observations are confirmed by CT imaging, resolved to 35 microns, and define the potentially substantial influence that benign changes in environmental conditions of stress, temperature, and chemistry may exert on transport properties.

Magnifying electronic endoscopes are frequently used to evaluate the pit patterns of the colorectal mucosa, but such endoscopes suffer from a number of problems. For example, they tend to have long, hard tips and heavy controller sections. In addition, the magnified endoscopic images obtained are often quite coarse due to the small number of pixels in the charge-coupled device (CCD). As a result, at higher magnification ratios, the orientation of the field of view is easily lost. A newly developed prototype colorectal electronic endoscope (Toshiba Corporation, Tokyo) overcomes these problems. The length of the hard tip of the scope and the weight of the controller section are comparable to those of the TCE-3680MH (Toshiba Corporation). High-resolution magnified images can be obtained, because a 410,000-pixel CCD is employed. Two magnification methods are available, optical magnification and electronic zooming, permitting images to be magnified by a factor of up to 90–120 without losing the orientation of the field of view. This newly developed magnifying electronic endoscope was found to be very useful, allowing us to observe the pit patterns of the colorectal mucosa in 82 small colorectal polyps measuring 7 mm or less in diameter.