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A method is described for the study of the kinetics of electrode reactions on the basis of analytical solutions of three transient electrochemical processes comprising the diffusion of ions in electrolyte, charge-transfer reactions, and charging process of an electrochemical double layer. The measured potential-time curves well agree with those predicted by the analytical solution.

Myocardial imaging with gallium-67 citrate was used to detect myocarditis in 46 consecutive infants and children (31 boys and 15 girls, mean age 21 months) with Kawasaki disease. In all of them planar imaging (group A) was performed at 6 hours and at 48 or 72 hours after the intravenous administration of a mean (SD) dose of gallium-67 citrate (0.07 (0.02) mCi/kg). Thirty four patients (24 boys and 10 girls, mean age 21 months) also had single photon emission computed tomography imaging (group B) soon after planar imaging. The patients had been ill for from 5 days to 16 days (mean (SD) 10.5 (2.4) days in group A and 10.6 (3.0) days in group B). The colour images obtained at 48 or 72 hours were positive in 41% of group A and in 64% of group B. Among the patients with clinically suspected myocarditis, 63% in group A and 80% in group B had positive myocardial images. Single photon emission computed tomography imaging permitted the identification of tracer in the myocardium, the pericardium only, or in the heart chambers. Myocardial imaging with gallium-67 citrate, especially when used with single photon emission computed tomography imaging, is useful for the detection of myocarditis in the acute phase of Kawasaki disease. [ABSTRACT FROM PUBLISHER]

This study investigated a technique for controlling the orientation of C2C12-derived myotube cells using ultrasonication for future clinical applications of cultured skeletal muscle tissues. An ultrasonicating cell culture dish, comprising a plastic-bottomed culture dish and a circular glass plate (diameter, 35 mm; thickness, 1.1 mm) attached to an annular piezoelectric ultrasonic transducer (inner diameter, 10 mm; outer diameter, 20 mm; thickness, 1 mm), was constructed. A concentric resonant vibrational mode at 89 kHz was generated on the bottom of the dish, and the orientations of myotube cells were quantitatively evaluated using two-dimensional Fourier transform analysis of phase contrast microscopy images captured over a 14 × 10 mm 2 area at the center of the dish. Unsonicated myotube cells grew in random directions, but ultrasonication aligned them circumferentially in the culture dish. The timing of treatment was important, with ultrasonication for 48 h before differentiation having a greater impact on myotube orientation than ultrasonication after differentiation. A larger ultrasonic vibration, with an amplitude of over 20 V pp , resulted in significantly smaller angles of deviation in the circumferential direction than the control. Ultrasonication enhanced the expression of differentiation-related genes and the formation of aligned myotubes, suggesting that it promotes differentiation of C2C12 cells into myotubes., (© 2024. The Author(s).)

The fabrication of so-called ghost-leg sheets and their electronic properties is reported. This unique sheet structure is composed of one-dimensional mixed-valence nickel chains, which are linked with one another by bis(azamacrocycle) ligands. They are also topologically unique Ni II /Ni III mixed-valence complexes, as confirmed by X-ray and optical measurements. Moreover, their magnetic susceptibilities indicated two-dimensional antiferromagnetic behavior following the Fisher 1D chain model with interchain interactions, where spins on Ni III sites mutually interact antiferromagnetically in the sheets., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A 77-year-old man had undergone left-lobe liver resection and a choledochojejunostomy six years previously, and thereafter he suffered from a postoperative relapse of cholangitis. He was admitted to our hospital due to liver abscesses and bacteremia caused by multidrug-resistant Pseudomonas aeruginosa. Empirical treatment with piperacillin/tazobactam was started, and the patient initially recovered. However, he developed a second case of sepsis caused by piperacillin/tazobactam-resistant P. aeruginosa bacteremia originating from a new liver abscess. We changed the piperacillin/tazobactam to colistin and flomoxef and continued the two antibiotics for one month. During the antibiotic therapy, the patient successfully underwent bile duct stent placement.

For the purpose of screening of inhibitors that are effective for wide range of metallo-beta-lactamases, the inhibitory effect of two series of compounds, 2-omega-phenylalkyl-3-mercaptopropionic acid (PhenylCnSH (n=1-4)) and N-[(7-chloro-quinolin-4-ylamino)-alkyl]-3-mercapto-propionamide (QuinolineCnSH (n=2-6)), where n denotes the alkyl chain length, on metallo-beta-lactamases IMP-1 and VIM-2 was examined. These inhibitors contain a thiol group and a hydrophobic group linked by variable-length methylene chain. PhenylCnSH (n=1-4) was found to be a potent inhibitor of both IMP-1 and VIM-2. PhenylC4SH was the potent inhibitor of both IMP-1 (IC(50)=1.2 microM) and VIM-2 (IC(50)=1.1 microM) among this study. When the number of methylene units was varied, QuinolineC4SH showed the maximum inhibitory activity against IMP-1 and VIM-2 (IC(50)=2.5 microM and IC(50)=2.4 microM). The relationship between the inhibitory effect of the alkyl chain length was different for both series of inhibitors, suggesting that IMP-1 has a tighter binding site than VIM-2. QuinolineCnSH did not serve as a fluorescence reagent for metallo-beta-lactamases.

We report an 18-year-old 46,XY phenotypic girl who has been on alternate-day dexamethasone therapy for 10 years. The patient was seen at our hospital for right-sided inguinal hernia at the age of 4 years. Biopsy of the herniated gonad showed testicular tissue, and the karyotype of the peripheral lymphocytes was 46,XY. The diagnosis of 17alpha-hydroxylase deficiency was established by the evaluation of adrenal steroidogenesis at the age of 6.1 years when hypertension was clearly recognized, and was confirmed later by the gene analysis of CYP17 which disclosed a compound heterozygote. The growth rate was suppressed during the initial treatment with daily administration of 0.25-0.5 mg dexamethasone. Switching to alternate-day regimen of dexamethasone 0.5 mg/dose improved height velocity. Subsequent addition of low-dose estrogen therapy induced pubertal growth spurt. The blood pressure and adrenal hormone levels remained almost within the normal range throughout the course. Adrenal function was evaluated at the age of 15 years. Plasma ACTH and corticosterone levels were high only just before the next administration, when the plasma dexamethasone concentration should be at the nadir. Since corticosterone possesses glucocorticoid activity and can work as a glucocorticoid reserve, it is assumed that this mode of dexamethasone administration can be a safe treatment for this disorder. We conclude that the patient with childhood 17alpha-hydroxylase deficiency can be safely and effectively treated with alternate-day dexamethasone without interfering with linear growth.

Prostacyclin (PGI2) is a bioactive substance produced by vascular endothelial cells, which exerts powerful vasodilative and anti-platelet actions. Patients with pulmonary hypertension have an imbalance between vasodilative PGI2 and vasoconstrictive thromboxane B2 (TXB2). Treatment with vasodilative agents is essential for such patients. Continuous intravenous infusion of PGI2 is an effective treatment of primary pulmonary hypertension in terms of exercise capacity and survival rate. We tested a new stable PGI2 analogue, beraprost sodium (Procyclin, Dornar) suitable for oral administration, in patients with primary and secondary pulmonary hypertension. A short-term study of cardiac catheterization in four patients with primary pulmonary hypertension showed a 15 +/- 12% reduction in mean pulmonary artery pressure in three of the four patients, and a 24 +/- 22% decrease in pulmonary vascular resistance in all four patients. Cardiac index increased by 27 +/- 14% in three of the four patients. Among three patients with secondary pulmonary hypertension, there was a 7% reduction in pulmonary artery pressure in one patient, and a 24 +/- 14% decrease in pulmonary vascular resistance in all three patients. In a long-term study (23 +/- 11 months), NYHA functional class improved from 3.0 +/- 0.7 to 2.4 +/- 0.5 in two of the five patients with primary pulmonary hypertension. Although the radiographic cardiothoracic ratio was not significantly improved, cardiac index increased by 78 +/- 60% in four of the five patients. Only two patients, one with primary and one with secondary pulmonary hypertension, died during the long-term follow-up period. Plasma TXB2/6-keto prostaglandin F1 alpha ratio decreased from 8.1 +/- 8.7 to 1.5 +/- 0.4. The optimal dose remains uncertain, but the initial dosage of 40-60 micrograms/day given in three to four doses for adult patients is considered to be acceptable. Side effects such as flushing face, headache, vomiting, and nausea were mild and resolved when the dose was reduced. Oral PGI2, beraprost, appears to be an effective and possibly adequate substitute for intravenous vasodilators in pulmonary hypertension for both short- and long-term management.

To elucidate the role of T cell subpopulations in the protective cell-mediated immune response at the initial phase of infection with Babesia microti (BM) and B. rodhaini (BR), the changes in the course of infection and anti-parasite delayed type hypersensitivity (DTH) response after BM or BR inoculation were investigated in Lyt-2+ T cell or L3T4+ T cell-depleted mice. Depletion of Lyt-2+ T cells strongly enhanced the resistance to BM infection, whereas it increased the susceptibility to BR infection. In contrast, depletion of L3T4+ T cells increased susceptibility to BM infection, while it enhanced resistance to BR infection. The anti-parasite DTH response in BM-infected mice was significantly enhanced by depletion of Lyt-2+ T cells, while significantly reduced by depletion of L3T4+ T cells. No effects of depletion of either Lyt-2+ or L3T4+ cells on DTH response was observed in BR-infected mice. From these results, it was suggested that the roles of Lyt-2+ and L3T4+ T cells in the protective cell-mediated immune response at the initial phase of infection were different between BM- and BR-infected mice, resulting in the difference in their course of infection.

In vitro cultivation of Babesia rodhaini (BR) and Babesia microti (BM) was attempted. When RPMI1640 was supplemented with 30 or 40% of non-treated fetal bovine serum (FBS), the gas mixture of 3% CO2-8% O2 best supported the growth of both parasites. Under this optimized condition, the percent parasitized erythrocytes peaked to approximately 4- and 2-times initial values for Br and BM, respectively. The cultivated parasites retained the infectivity to the host mice. BM showed the characteristic feature of division during cultivation. However, the lots of FBS will have to be taken into consideration, since the FBS lots were shown to give large varieties to the results. Selection of the appropriate FBS lot may yield the better growth of these protozoa.

A comparative study was carried out on the glucose metabolism in Babesia microti (BM) and Babesia rodhaini (BR) by analyzing the enzyme activities. The lactate dehydrogenase (LDH) activity in BM showed significantly lower values than that in BR, whereas citrate synthase (CS) and malate dehydrogenase (MDH) activities were remarkably higher in BM. In addition, pyruvate dehydrogenase (PDH), isocitrate dehydrogenase (ICDH), alpha-ketoglutarate dehydrogenase (KGDH), and succinate dehydrogenase (SDH) activities also tended to be higher in BM. Then, the change of enzyme activities related to the proliferation of parasites was examined. In BM infected mice, the parasitemia increased from day 15 to day 19 after inoculation (a.i.). While BM showed decrease of G6PD and LDH activities at day 19 a.i., it showed remarkably increased activities in CS and MDH (368 and 8,842 nmol/min.mg protein, respectively). In addition, PDH, ICDH, KGDH, and SDH activities also tended to increase from day 15 to 19 a.i. In BR infected mice, parasitemia increased from day 9 to day 12 a.i. LDH activity showed a considerable increase at day 12 a.i. (12,920 IU/mg.protein). Although CS and MDH activities also showed a slight increase at day 12 a.i., the activities of PDH, ICDH, KGDH and SDH didn't change from day 9 to 12 a.i. Since these changes observed in the enzyme activities of BM and BR seemed to be correlated with their proliferation, it was suggested that BM and BR depended on aerobic and anaerobic pathways, respectively, for their glucose metabolism.

We examined whether human left ventricular (LV) wall vibration at the first heart sound emission (LVvibr) could be a potential source of information about the left ventricular physical properties, as has been demonstrated by experimental forced vibration studies. LV posterobasal wall vibration in 51 subjects characterized by functional murmur (n = 13), mitral stenosis (n = 8), hypertrophic cardiomyopathy (HCM, n = 8), ischemic heart disease with old myocardial infarction (n = 12) and without prior infarction (n = 10), was detected with a miniature intraesophageal vibration sensor. Peak frequency, sharpness and peak power of LVvibr in patients with functional murmur and mitral stenosis were linearly related to the Q-vibration interval. HCM patients showed a higher peak frequency and sharper configuration in the power spectrum. However, differing from previous reports, we found no characteristic difference in configuration of power spectrum in patients with ischemic heart disease. These results suggest that human LVvibr possibly includes information demonstrated by experimental forced vibration analysis.

A technique simpler than the angiographic method for estimating aortic regurgitant volume was tried with 31 patients with aortic insufficiency. During cardiac catheterization, we injected dye into the descending aorta while recording the dye dilution curve in the left ear. The distance between the aortic arch and the tip of the catheter at the lowest point from which the injected dye could be detected in the left ear was rated in terms of the number of corresponding vertebral bodies. This "distance score" closely correlated with the regurgitant stroke volume and with the fraction to total stroke volume, which were measured by angiocardiography (r = 0.927, p less than 0.001; and r = 0.900, p less than 0.001, respectively). The correlation coefficients of the aortographic grade to those parameters were not as high as they were in the relationship of the score to the same parameters. Therefore, these results indicate that the "distance score" is a practical method for assessing the magnitude of aortic regurgitant volume.

Two cases of hypoplastic coronary artery (HCA) are presented. Case 1, a 13 year old girl, died suddenly during a long distance race. She had HLCA with marked intimal thickening and an ectopic left coronary ostium above the commisure between the non-coronary and left coronary cusp at post mortem examination. The right coronary artery (RCA) was enlarged and also supplied parts of the area normally supplied by the left coronary artery (LCA). Pathological findings revealed a normal RCA and an extremely hypoplastic LCA with occlusive proliferation of the intima and a myocardial infarction of the left ventricle. Case 2, a 6 year old girl, had a history of effort angina. Selective coronary angiography was performed which failed to demonstrate the orifice of the LCA by aortography. However, the hypoplastic LCA was visualized by RCA angiography as a consequence of anomalous collaterals from the atrioventricular branch of the RCA. We postulate that HCA results from various conditions, including stenosis of the coronary artery orifice, an aberrant course between the pulmonary artery and aorta and ectopic positioning of the coronary artery ostium. In addition, HCA may also be associated with occlusive coronary artery abnormalities.

Endomyocardial biopsy was performed on eight children 5 to 12 years old, who were in post myocarditic state. They were evaluated within 2 to 25 months (mean lyr and 1 m) after the onset of the symptoms. Two of the patients developed heart failure and six patients developed other cardiac manifestations such as syncope, palpitation or ECG abnormalities at onset. Definite elevation of viral antibody titer was observed in four patients. Radionuclide angiography was also performed in all eight patients. An abnormal perfusion area was observed in six patients as a focal hypoperfusion area by T1-201 myocardial imaging. Ejection fraction was examined by Tc-99m-HSA gated equilibrium ventriculography. LVEF was reduced in 3 patients and RVEF was reduced in 2 patients. Judging from the histopathological findings, these patients were divided into three categories: chronic or smoldering myocarditis (3 patients); healing or healed myocarditis (4 patients); and post myocarditic hypertrophy (1 patient). Measurement of left ventricular function was obtained by cardiac catheterization and left ventriculography (LVG), which revealed some abnormal findings such as increased left ventricular mass index, increased left ventricular end diastolic volume index (LVEDVI) and reduced left ventricular ejection fraction (LVEF). Therefore, endomyocardial biopsy findings of pediatric patients in a post myocarditic state reveal certain histopathological abnormalities even in the long-term follow-up period in the absence of cardiac dysfunction.

Several investigators have aimed to clarify the patient's left ventricular (LV) physical properties by free vibration analysis of heart sound. Recently we have developed a transfer function (TF) method to calculate the LV viscoelasticity. To clarify whether this TF method and a clinical first heart sound (1 HS) analysis are based on the identical ventricular vibration mode analysis, we examined (1) the visualized LV vibration image in the TF method and (2) the quantitative relationship between the peak frequency of the 1 HS spectrum and that of TF curve in the early and late phase of the 1 HS. Isolated isovolumic potassium arrested canine left ventricles were used to visualize the vibration mode in describing the TF (N = 2). Examination of stroboscopically illuminated, slow-motion images revealed the oscillation of the ventricle to be of mode 2 behavior. To analyze the quantitative relation between the TF method and 1 HS analysis we used ten open-chest dogs. The correlation was good (r = 0.917) when the peak frequency of the TF curve at the early phase of the 1 HS was compared to the peak frequency of the 1 HS. We concluded that both the TF method and 1 HS analysis were based on the common, second-order ventricular vibration mode. Therefore, some information on the ventricular physical properties suggeted by the TF method could also be included in the clinical data obtained by 1 HS analysis.

A new method was developed to describe the instantaneous resonance curve (IRC) of the left ventricle (LV), which represents the acoustic characteristics and instantaneous viscoelastic properties of LV. This method was evaluated using coronary-perfused isolated canine LV preparations.

Although sympathetic excitation during mild exercise may readily occur in patients with mitral stenosis (MS), the degree of increment in plasma catecholamines has not been fully investigated. We imposed mild ergometric exercise (50 watts, 300 kg/min for 5 minutes) on five patients with mild MS (mitral valve area greater than or equal to 1.0 cm2) and eight with severe MS (mitral valve area less than 1.0 cm2) while they were undergoing cardiac catheterization. In patients with severe MS, total plasma catecholamine levels during exercise were remarkably higher (2821 +/- 783 [SEM] pg/ml) than in those with mild MS (957 +/- 113 pg/ml, p less than 0.05) and in seven control subjects (612 +/- 75 pg/ml, p less than 0.05). This marked increment could not be predicted by heart rate response, which did not differ between severe and mild MS (166 +/- 5 vs 153 +/- 10 bpm). In contrast with catecholamine change, the cardiac index in severe MS showed a very small increment. Results suggest that mild daily exercise can remarkably increase plasma catecholamine levels in severe MS, and this may accelerate various complications of this disorder.

T1-201 myocardial imaging and Tc-99m-HSA gated equilibrium ventriculography were performed in 1 infant and 11 children between 2 months old and 12 years old with myocarditis. The time of first evaluation was between 1 week and 13 months after the onset. Their clinical manifestations were congestive heart failure in 2 patients, pericardial effusion in 2 patients, syncope in 1 patient, convulsions in 1 patient and palpitations in 7 patients. Significant elevation of virus antibody titer was demonstrated in 6 patients. A perfusion defect was observed with T1-201 imaging in 9 of 12 patients with myocarditis. A right ventricular image was observed in 5 patients. A reduced LVEF was present in 4 patients and a reduced RVEF was found in 2 patients. Cardiac catheterization was performed in 8 patients and an endomyocardial biopsy was done in 7. The myocardial specimens revealed postmyocarditic pathological changes upon microscopic evaluation. No coronary artery obstructive or stenotic lesions were observed in these patients. T1-201 myocardial imaging is a useful non-invasive technique for evaluating the cardiac performance and myocardial damage in acute myocarditis and the postmyocarditic state. We conclude that T1-201 uptake of myocardium is dependent upon both regional coronary perfusion and the activity of myocardial cells in patients with myocarditis and in the postmyocarditic state.

We studied the feasibility of using the impedance frequency curve method (IFM) to detect the myocardial physical heterogeneity of a cross-circulated isolated canine left ventricle with regional ischemia. The curve changed from a single-peak configuration to a double-peak configuration after the LAD coronary flow cessation and returned to the single-peak configuration with the reperfusion of LAD coronary flow. We concluded that IFM can be a useful tool to describe the physical heterogeneity of the ventricular muscle under the regional ischemia.