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With developments in analytical devices promoted by nanofluidics, estimation of the flow rate in a nanochannel has become important to calculate volumes of samples and reagents in chemical processing. However, measurement of the flow rate in nanospaces remains challenging. In the present study, a mass flowmetry system was developed, and the flow rate of water by pressure-driven flow in a fused-silica nanochannel was successfully measured in picoliters per second. We revealed that the water flow rate is dependent on the viscosity significantly increased in a square nanochannel with 10 2  nm width and depth (3.6 times higher than the bulk viscosity for a representative channel size of 190 nm) and slightly increased in a plate nanochannel with micrometer-scale width and 10 2  nm depth (1.3 times higher for that of 234 nm), because of dominant surface effects. The developed method and results obtained will greatly contribute to nanofluidics and other related fields., (© 2022. The Author(s), under exclusive licence to The Japan Society for Analytical Chemistry.)

To elucidate the changes in oxidative metabolism in hibernating myocardium after coronary revascularization, we performed myocardial single-photon emission computed tomography with a free fatty acid analog, I-123 beta-methyliodophenylpentadecanoic acid (BMIPP), and thallium-201 before and 1 month after percutaneous transluminal coronary angioplasty (PTCA) in 11 patients with angina pectoris caused by single artery stenosis. All patients had improvement in wall motion after PTCA at the region with coronary stenosis; the wall motion abnormality score evaluated by left ventriculography decreased from 5.5+/-0.8 (mean +/- SE) to 2.1+/-0.9, p <0.01) after PTCA. The defect score of I-123 BMIPP images was significantly larger than that of thallium-201 images either before (14+/-1.3 vs 8.9+/-1.1, p <0.01) or 1 month after (7.4+/-1.5 vs 3.7+/-0.8, p <0.01) PTCA. The decrease in the defect score of both images was significant (p <0.01). Changes in the wall motion abnormality score showed a significant correlation with both the change in the defect score of thallium-201 images (r = 0.58, p < 0.01) and that of I-123 BMIPP images (r = 0.75, p <0.01). These results indicate that the metabolism of free fatty acid is impaired in hibernating myocardium, and that improvement in left ventricular function after successful PTCA is strongly associated with the recovery of oxidative metabolism.

Unlabelled: Coronary pressure flow (P/F) relationship has been investigated mainly from the viewpoint of coronary resistance. However, recent experimental evidence suggests that the zero flow pressure intercept (Pzf) provides important characteristics of coronary circulation. Although Pzf is likely to provide meaningful information about characteristics of coronary circulation, no data are available about Pzf in humans. The authors attempted to determine Pzf in humans by analyzing P/F relationship during long cardiac pause. This relationship, provoked by intracoronary adenosine triphosphate (ATP) infusion, was analyzed in 9 patients (8 men, 1 woman) with coronary heart disease (ages: fifty-six +/- six years). After the diagnostic cardiac catheterization, ATP, 0.6 mg/3 mL, was administrated by bolus intracoronary injection during measurements of coronary blood flow velocity. Coronary blood flow velocity in the left anterior descending artery was measured with a 0.018-inch Doppler angioplasty guide wire (FloWire, Cariometrics, Inc., Mountain View, Calif.). The dynamic P/F relationship was obtained by correlation of the instantaneous aortic pressure and flow velocity with each other at constant intervals. The least square linear regression analysis was applied to the P/F data to yield the extrapolated Pzf axis. Immediately after intracoronary injection of ATP, long pause (5320 +/- 1498 msec) appeared and coronary blood flow velocity decreased to 11 +/- 8 cm/sec. Pzf calculated with P/F relationship was 14 +/- 7 mmHg., Conclusions: Thus, the results clearly demonstrate that Pzf is higher than right atrial and left ventricular end-diastolic pressure in humans, indicating the complexity of the determinants of the Pzf.

In 100 patients who underwent coronary angioplasty with more than one balloon catheter for a lesion, these over-the-wire balloon catheters were changed by using a regular-length guidewire. In order to change to another balloon, the inflation device was connected to the central guide wire lumen of the catheter after pulling back the catheter until the proximal end of the regular length guide wire disappeared. By pulling back the balloon catheter from the guiding catheter by applying a pressure with the inflation device, the balloon was taken out of the guiding catheter leaving the wire in the coronary artery. One hundred forty-nine of 163 attempted procedures were completed successfully. Our technique helped in performing a fast, safe, and reliable changing procedure compared to the procedure with an extended guidewire.

To test the hypothesis that aggressive cholesterol lowering results in a rapid regression of coronary atherosclerosis, the effect of low-density lipoprotein (LDL)-apheresis for 1 year on coronary artery diameters was studied in patients with heterozygous familial hypercholesterolemia. LDL-apheresis was performed every 2 weeks in 13 patients with LDL-cholesterol levels > or = 200 mg/dL despite treatment with conventional dietary and drug therapies. Coronary arteriography was performed before and 1 year after the initiation of treatment. The LDL-cholesterol level was decreased by an average of 71% immediately after the initial LDL-apheresis and by 30% before the second apheresis. Such phasic changes were observed throughout the trial. Computer-assisted automated quantitative arteriograms analyzed 101 proximal coronary segments. The mean lumen diameter of angiographically normal sections of each segment was slightly but significantly increased from 2.93 +/- 0.89 mm at baseline to 3.05 +/- 0.93 mm at the follow-up arteriogram (P < 0.05); 54 of the 101 segments showed a lesion stenosed by 20% or more in diameter. The minimal diameter of individual lesions was also significantly increased from 2.17 +/- 0.67 mm to 2.36 +/- 0.76 mm (P < 0.05), and thus the diameter stenosis was significantly reduced from 32.3 +/- 10.5% to 28.2 +/- 12.1% (P < 0.05). It is concluded that 1 year of aggressive cholesterol lowering, using LDL-apheresis, can significantly reduce coronary atherosclerosis in patients with familial hypercholesterolemia.

We describe a patient with Wegener's granulomatosis in whom the serum levels of interleukin-6 (IL-6) and other laboratory parameters were monitored. The IL-6 and CRP levels, which were extremely high before treatment, declined rapidly with corticosteroid and cyclophosphamide. IgG, leukocyte count and platelet count declined more gradually. Thus, determination of the serum IL-6 level might be useful in diagnosing and monitoring Wegener's granulomatosis.

A case of thrombotic thrombocytopenic purpura (TTP), in which vincristine (VCR) administration played a pivotal role in achieving the hematological remission, is presented. A 40-year-old woman with a chief complaint of purpura was transferred for detailed examination of thrombocytopenia. The presence of hemolytic anemia, schistocytosis, febrile clinical course, renal dysfunction and neurological abnormalities made the basis of a diagnosis of TTP. Twelve courses of consecutive plasma exchange and plasma infusion, which amounted to a total of 120l of fresh frozen plasma, were performed without obvious hematological improvement. Therefore, VCR (2 mg) was infused in addition to the plasma exchange. Three days later, platelets responded remarkably. After 10 days of hematological improvement, relapse occurred. VCR was reinfused. However, the second VCR infusion alone was not able to elevate platelets. With concomitant use of significant amounts of plasma, the platelet count responded gradually. Hematological remission was obtained and has continued until now. The exact role of VCR for TTP is still unknown; however, VCR is suggested to be effective for TTP as in the case presented here.

The authors describe a patient in whom the serum levels of interleukin-6 (IL-6) and other laboratory parameters were monitored. The IL-6 and C-reactive protein (CRP) levels, which were extremely high before treatment, declined rapidly with administration of prednisolone. Rheumatoid factor, IgG, and platelets count declined more gradually. Thus, determination of the serum IL-6 level might be useful in diagnosing and monitoring polyarteritis nodosa.

A fatal case of acute fulminant hepatitis following exposure to dichloropropanols is reported. A 59-year-old male worker in a chemical plant developed general malaise, nausea and vomiting several hours after cleaning a tank that had contained dichloropropanols. He had no previous history of hepatic dysfunction. On admission, hepatomegaly was prominent. Because of highly elevated levels of GOT and GPT in the serum, reduced prothrombin time and a lowered consciousness level, a diagnosis of fulminant hepatitis was made. Significant decreases of leukocytes and platelets were also observed. Serum creatinine and BUN were slightly elevated. Although plasma exchanges were conducted on the third and fourth day, the liver functions continued to deteriorate. The patient died on the fifth day. Because dichloropropanols could be detected in the blood specimens obtained at the time of admission, we considered that fulminant hepatitis in this case was attributed to dichloropropanols exposure. To our knowledge, this is the first case of fulminant hepatitis after dichloropropanols-exposure.

Plasma levels of interleukin-6 (IL-6), a cytokine known to be involved in lymphocyte activation and in inflammation, were studied in 10 normal volunteers, 21 continuous ambulatory peritoneal dialysis (CAPD) patients and 41 hemodialysis patients. Plasma IL-6 levels in hemodialysis patients were significantly higher than those in normal volunteers and CAPD patients (p less than 0.05). The means of plasma IL-6 concentrations before and after hemodialysis did not change significantly. While IL-6 in peritoneal dialysate was detectable in only 3 of the 21 CAPD patients without peritonitis, it was extremely high in 2 patients with bacterial peritonitis. IL-6 levels decreased as peritonitis subsided.

Acquired calcified aortic stenosis in elderly patients successfully resolved after percutaneous aortic valvuloplasty (PAV) using the antegrade or retrograde method. The effectiveness and complications of these two methods were compared. A 79-year-old man who had acute myocardial infarction and pulmonary emphysema underwent aortic valvuloplasty using Medi-Tech balloons, 15 mm and 20 mm in diameter, via the brachial artery route. This caused a reduction of the peak and mean aortic valve pressure gradients, from 56 to 30 and from 59 to 35 mmHg, respectively and an increase in the valve area from 0.6 to 0.8 cm2. However, cardiac tamponade developed due to penetration of the left ventricular wall by the guide wire. A 73-year-old man who had transient cerebral ischemia and pulmonary emphysema underwent valvuloplasty by the Inoue's balloon technique (inflated up to 19 mm) via the saphenous vein. This resulted in a reduction of the peak and mean pressure gradients from 35 to 15 and from 39 to 15 mmHg respectively, a month thereafter. There were no complications. To our knowledge, these are the first two reported cases of acquired aortic stenosis which were relieved by percutaneous aortic valvuloplasty in Japan.

Percutaneous transvenous mitral valvuloplasty (PTMV) using the Inoue balloon was performed in 18 patients with symptomatic mitral stenosis. They were seven men and 11 women, ranging in age from 38 to 77 years (mean 59 +/- 10 years). Among them, 13 were categorized as NYHA class II; four as class III; and one as class IV. As a result, the symptoms of 14 patients markedly improved. Survey by means of right and left heart catheterization and echocardiography before and after PTMV demonstrated significant improvement in test values; (1) a decrease in the mean mitral gradient from 8.5 +/- 3.3 to 4.8 +/- 2.0 mmHg (p less than 0.01), (2) an increase in the mean diastolic descent rate of the mitral valve from 17.6 +/- 8.3 to 25.1 +/- 8.1 mm/sec. (p less than 0.01), and (3) an increase in the mean mitral valve area from 1.3 +/- 0.5 to 1.7 +/- 0.5 cm2 (p less than 0.01). Bicycle ergometer stress test performed on the 13 patients before and after PTMV revealed a significant decrease in the mean pulmonary arterial pressure from 24 +/- 5 to 18 +/- 5 mmHg (p less than 0.01) at rest, and from 49 +/- 9 to 42 +/- 7 mmHg (p less than 0.05) after exercise. The degree of mitral regurgitation increased after PTMV in six patients, in three of whom it was severe. The severity was evidenced by a significant increase in the ratio of the mean balloon diameter to body surface area as compared with the data of the other 15 patients (20.6 +/- 2.2 to 18.0 +/- 1.4 mm/m2; p less than 0.05), the presence of a localized sclerosis of the mitral valve as demonstrated by two-dimensional echocardiography, and prolapse of the mitral valve as shown by a left atriogram. These early results indicated that PTMV using the Inoue balloon is an effective treatment for symptomatic patients with mitral stenosis unless severe mitral regurgitation develops. This complication may be partially due to the selection of an inappropriate balloon diameter, and due to co-existing myxomatous degeneration and localized sclerotic changes of the mitral valve.