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K Taniguchi

Publications and source records attributed to K Taniguchi.

At least 541 records · Page 30Linked to original sources

[The influence of aging on parathyroid hormone-induced enhancement in (Ca2+ + Mg2+)-ATPase activity of rabbit renal basolateral membrane].

We studied the influence of aging on the stimulatory effect of parathyroid hormone (PTH) to (Ca2+ + Mg2+)-ATPase activity of rabbit renal basolateral membrane (BLM). Stimulated by PTH, (Ca2+ + Mg2+)-ATPase activity of BLM from aged rabbits was lower than those from young rabbits. However, the stimulatory effect of cyclic AMP (cAMP) showed no differences in terms of (Ca2+ + Mg2+)-ATPase activity in BLM from aged and young rabbits. As cAMP production in BLM caused by PTH stimulation was not measured, it is unclear whether cAMP production is different in BLM from young and aged rabbits. From these results, we concluded that in BLM from aged rabbit, the lower effect of PTH on (Ca2+ + Mg2+)-ATPase is due to lower production of cAMP or some other disorder of the PTH signal transduction mechanism. As (Ca2+ + Mg2+)-pump plays an important role in Ca2+ reabsorption in kidney, its lower activity in aged rabbit may be one reason for aberration of renal calcium handling.

Aging↗

Conformational change accompanying formation of oligomycin-induced Na(+)-bound forms and their conversion to ADP-sensitive phosphoenzymes in Na+,K(+)-ATPase.

Oligomycin reduced the fluorescence intensity of an N-(p-(2-benzimidazoly)phenyl) maleimide (BIPM) probe at Cys-964 of the alpha-chain of pig kidney Na+,K(+)-ATPase with increase in the concentration of Na+ with a Hill coefficient of nh = 0.77 with Kh = 231 mM. The maximum fluorescence decrease was around 80% of the value observed after accumulation of ADP-sensitive phosphoenzyme (E1P) in the presence of 2 M Na+. The addition of Mg2+ and ATP with Na+ or choline chloride to give the same final ligand concentration to the Na(+)-enzyme-oligomycin complex formed with 16 mM Na+ + 1,984 mM choline chloride or 2 M Na+ induced rapid phosphorylation (20 or 21/s) and slower fluorescence decrease (12.1 +/- 1.2 or 10.1 +/- 3.2/s). These additions to the Na(+)-enzyme complex formed under the former or the latter conditions induced slow phosphorylation (13/s) prior to a much slower fluorescence decrease (3.4 +/- 0.3 or 8.6 +/- 0.7/s). The addition of Ca2+ and ATP to these enzyme complexes induced rapid fluorescence changes (21-11/s) followed by one order of magnitude slower rates of phosphorylation (1.5-1.3 s). These data suggest that the decrease in BIPM fluorescence induced by ATP with Ca2+ or with Mg2+, reflects the change of the Na+ binding state before or after the formation of E1P, respectively.

Adenosine Diphosphate↗

Preparation of a neutralizing monoclonal antibody specific to serotype 8 rotavirus strains with a super-short RNA pattern.

Extensive cross-neutralization tests have identified seven serotypes of rotavirus. Recently, it has been reported that several human strains (69M, B37 and B38) with a super-short RNA pattern carry new serotype specificity (serotype 8). By using the strain 69M as an immunizing antigen, we prepared a neutralizing monoclonal antibody (designated 69M-2D). In neutralization tests using 18 human and two animal rotavirus strains with different serotype specificities, the 69M-2D antibody was found to neutralize only serotype 8 strains. Also, in an enzyme-linked immunosorbent assay (ELISA), the antibody reacted exclusively with the serotype 8 strains. Thus, the reactivity pattern of the 69M-2D antibody was serotype 8-specific. This antibody should be useful as another reagent for serotyping rotaviruses by ELISA.

Animals↗

Effects of transcatheter hepatic arterial embolization on coagulation and fibrinolysis in patients with hepatocellular carcinoma.

The changes in coagulation and fibrinolysis were studied in cases of hepatocellular carcinoma with (n = 20) and without (n = 8) transcatheter hepatic arterial embolization (TAE). The plasma levels of thrombin-antithrombin III complex (TAT) and alpha 2 plasmin inhibitor complex (PIC) were significantly elevated after TAE, concurrently with a decrease in antithrombin III and antiplasmin (alpha 2-plasmin inhibitor) levels. The elevation of TAT was most significant (2.4-fold of the pre-TAE level) on day 3, whereas that of PIC was relatively less (1.3-fold on day 3). Tissue plasminogen activator in blood was also significantly increased on day 1, but it was decreased thereafter, although plasminogen activator inhibitor (PAI) remained high for at least 7 days after TAE. In contrast, such hematological changes were not observed in patients without TAE. Thus, both coagulation and fibrinolysis were activated after TAE, but its effect on fibrinolysis was less prominent, due probably to the increased synthesis of PAI.

Adult↗

Echocardiographic comparison of postoperative left ventricular contractile state between one- and two-stage arterial switch operation for simple transposition of the great arteries.

Left ventricular contractile function was compared between primary and two-stage arterial switch operation (ASO) in neonates and infants with simple transposition of the great arteries (TGA). Eight patients (group 1) underwent primary ASO at 13-42 (23 +/- 10 [mean +/- SD]) days of age, and five patients (group 2) underwent two-stage ASO after pulmonary artery banding and Blalock-Taussig shunting at 11-26 (15 +/- 3) months of age. Postoperative echocardiographic studies were undertaken at 6-48 (22 +/- 16) months of age in group 1 and 25-45 (32 +/- 7) months of age in group 2. The results were compared with those obtained from nine age-matched normal children (group N). To compare left ventricular contractile state among the patients, the deviations from the mean normal values in relations of end-systolic wall stress to fractional shortening and to rate-adjusted mean velocity of circumferential shortening (the stress-shortening index and stress-velocity index, respectively) were obtained for each patient. The stress-shortening index was significantly lower in group 2 (-3.1 +/- 3.1) than in group 1 (1.3 +/- 1.7, p less than 0.05); the stress-velocity index was significantly lower in group 2 (-3.3 +/- 1.8) than in group 1 (1.5 +/- 1.6, p less than 0.01) or in group N (-0.4 +/- 0.5, p less than 0.05). These results suggest that postoperative left ventricular contractility can be well preserved in patients after primary ASO for simple TGA in neonates, but there is a possibility of depressed contractility in patients after two-stage ASO.

Cardiac Surgical Procedures↗

[A comparison of three drugs (pethidine, magnesium sulfate and droperidol) in patients with post-anesthesia shivering].

Shivering is one of the common complications after general anesthesia. It increases metabolic rate markedly and may cause myocardial ischemia in patients with decreased cardiopulmonary function. We investigated, therefore, the effects of three drugs (pethidine, magnesium sulfate and droperidol) on shivering in 30 patients under enflurane anesthesia. The patients were of ASA class I or II physical status and had no cardiovascular or respiratory disease. For post-anesthesia shivering, every patient was administered with pethidine 0.5 mg.kg-1, MgSO4 30 mg.kg-1 or droperidol 0.15 mg.kg-1. Their VO2 and VCO2 were measured for 5 minutes during shivering and 15 minutes after drug administration. We also evaluated the therapeutic efficacy of each drug for the treatment of shivering by examining VO2 and VCO2 before and after drug administration. With pethidine and MgSO4, both VO2 and VCO2 decreased significantly after each drug administration. With pethidine, VO2 and VCO2 decreased significantly more than that in MgSO4 (P less than 0.01 vs P less than 0.05). But with droperidol, there was no significant change. These results suggest that pethidine is most effective followed by MgSO4.

Adult↗

[Interleukin-2 (IL-2) in active pulmonary tuberculosis].

To clarify the precise of cellular immunity mechanism in pulmonary tuberculosis, we investigated the amount of IL-2 in patients with untreated active pulmonary tuberculosis. When serum adenosine deaminase (ADA) activity was examined using enzyme assay, an abnormally high level was observed in all patients (29.0 + 11.6 IU/ml, mean + SD; 4.5-17.8, normal range). Likewise, the level of serum-soluble interleukin-2 receptor (IL-2R) measured by ELISA showed abnormal high level in all patients (844.3 + 584.8 IU/ml; 80-300, normal range). When stimulated using PHA, the peripheral lymphocyte's ability to produce IL-2 revealed no difference between control subjects and patients. It was, however, noted that the lymphocytes of the patients significantly suppressed IL-2 responsiveness when compared to the control subjects (P less than 0.05). The serum IL-2 concentration measured using RIA could not be detected in any of the patients as was the same for control subject. All of the above mentioned results suggest that T-cell activation which caused increment in serum ADA activity and soluble IL-2R occurred in active pulmonary tuberculosis. The suppressed IL-2 responsiveness in the peripheral lymphocytes of patients proposes the possibility of soluble IL-2R reduction by the negative feedback mechanism in IL-2-sensitive lymphocytes.

Adenosine Deaminase↗

[Hemodynamics].

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Acute Kidney Injury↗

[The prevalence and clinical features of pathologically abnormal mitral valve leaflets (myxomatous mitral valve) in the mitral valve prolapse syndrome: an echocardiographic and pathological comparative study].

We studied the prevalence and clinical features of pathologically abnormal mitral valve leaflets (myxomatous mitral valve: MMV) in consecutive 142 patients with the mitral valve prolapse syndrome (MVP). Our echocardiographic criteria for MMV were 1) thick leaflets 3 mm or greater, 2) redundant leaflet-motion, and 3) echo-density lower than that of the aortic walls. The echocardiographic measurements of left ventricular diastolic dimensions (LVDd), percent fractional shortening (%FS), mitral annular diameter (MAD), and LV mass were compared between MMV and non-MMV groups. Twelve patients (8%) were referred for surgery because of congestive heart failure, and two patients died during the observation periods. Gross morphology of the MMV was characterized by increased surface area, dome formation of the leaflet-body, and non-uniform leaflets in thickness, and histologic findings of the MMV were the infiltration of spongiosa layer into the fibrosa layer. The diagnostic accuracy of echocardiography for the MMV was examined in 14 patients underwent either surgery or autopsy, and it was high (78% in sensitivity and 80% in specificity). The progression of mitral regurgitation (MR) from mild to moderate grade or mild to severe grade was found in five of 26 patients during follow-up studies over 12 months (mean = 36 months). All of the five patients were aged 50 years and older. While, MR completely disappeared in a 17-year-old boy with marked physical development within three years of the observation period. Mitral annular diameter significantly increased in MMV with MR when compared to non-MMV with MR (4.1 +/- 0.7 vs 3.5 +/- 0.4). But no significant changes were noted in LVDd and LV mass between non-MMV with MR and MMV with MR. Of the 142 patients with MVP, 96 patients were non-MMV and 46 patients were MMV. Ruptured chordae tendineae were associated in 5/96 patients (5%) with non-MMV and 22/46 patients (48%) with MMV. Intracardiac vegetations were seen in four of the 96 patients (4%) with non-MMV. The prevalence of MMV in MVP was greater in older patients, and it reached nearly as high as 50% of MVP patients aged 60 years and older. In conclusion, the echocardiographic diagnostic criteria for MMV are reliable with high sensitivity and specificity, and are useful to predict the high risk patients in the MVP syndrome. MMV may be a potential etiology causing aggravation of mitral regurgitation and/or ruptured chordae tendineae.

Adolescent↗

[Timing of operation based on evaluation of postoperative left ventricular contractility in patients with aortic regurgitation].

To evaluate the effect of aortic valve replacement on left ventricular function in aortic regurgitation, the ratio of end-systolic wall stress to end-systolic volume index (ESS/ESVI) and standard ejection phase indexes of left ventricular function were measured angiographically in 29 patients with isolated, chronic aortic regurgitation before and an average of 26 months after aortic valve replacement. The patients were divided into three groups based on preoperative left ventricular volume at end-systole (ESVI); 12 patients had an ESVI smaller than 100 ml/m2 (group I), 11 had an ESVI of 100 to 200 ml/m2 (group II) and 6 had an ESVI greater than 200 ml/m2 (group III). Postoperatively, end-diastolic volume index and ESVI decreased markedly in all 3 groups and end-systolic stress also decreased. Systolic pump performance assessed as ejection phase indexes improved in all groups with group I and group II showing normal or near-normal ejection fraction, while group III still had a depressed ejection fraction. Left ventricular contractile function as assessed by ESS/ESVI improved significantly in each group postoperatively. After operation, group I patients had normal values. However, both group II and group III still had a subnormal ratio, suggesting a depressed contractility despite normal or near normal systolic pump performance. Surgical correction for aortic regurgitation should be considered before a preoperative ESVI exceeds 100 ml/m2, to preserve postoperative left ventricular contractility.

Adult↗

[Effects of antianginal drugs on left ventricular diastolic filling in patients with ischemic heart disease].

To study the acute effects of isosorbide dinitrate (ISDN), nifedipine, propranolol and placebo on left ventricular diastolic filling in patients with myocardial ischemia, we repetitively performed exercise radionuclide angiography (RNA) following random assignment of each drug in 12 patients with effort angina pectoris, and 5 normal controls. Left ventricular time activity curves were constructed using computer technique. We obtained changes of hemodynamic parameters such as endodiastolic volume, systemic vascular resistance and ejection fraction. The peak filling rate (PFR), and filling rate in the first third of the diastolic period (1/3 FR) were used as the indexes of LV diastolic filling. 1/3 FR remained unchanged during peak exercise by the patients, while it increased significantly in normal controls. After administration of ISDN and nifedipine, 1/3 FR increased significantly during peak exercise by the patients. Especially after nifedipine, 1/3 FR improved significantly compared with the improvement after ISDN, although these two drugs had the same effects on systolic function. These findings showed that 1/3 FR was reliable as an indicator of LV diastolic filling in ischemic heart disease, and nifedipine improved LV diastolic filling not only by improving ischemic changes in myocardium but also by it's direct effect on left ventricular relaxation.

Aged↗

Long-term survival and complications after composite graft replacement for ascending aortic aneurysm associated with aortic regurgitation.

The Bentall operation was performed in 44 patients between March 1972 and December 1988. Twenty patients had stigmata of Marfan's syndrome, and 15 had aortic dissection. All showed annuloaortic ectasia. Follow-up ranged from 1 to 16 years (mean, 5.8 years). There were six early deaths (14%) and seven late deaths (16%), with actuarial survival at 10 years of 65 +/- 8%. The late deaths were mostly related to aneurysms occurring in the remainder of the aorta. No patient has undergone reoperation related to the composite graft, but six patients required seven subsequent operations on the remaining aorta. The actuarial probability of freedom from late death and subsequent operation at 8 years was 64 +/- 9% for the operative survivors, but it was 44 +/- 17% for the patients with aortic dissection and 37 +/- 19% for those with Marfan's syndrome. Postoperative angiography performed 3-168 months (mean, 42 months) postoperatively in 23 nonselective patients demonstrated recurrent true aneurysms at both or one of the coronary ostia (seven), persistent dissection distal to the distal aortic anastomosis (five), pseudoaneurysm at the left coronary ostium (one), pseudoaneurysm due to a small leak at the proximal aortic anastomosis (one), and partial dehiscence of the distal aortic suture line (one). Composite graft replacement carries a potential risk of various late complications. Our data support the concept that earlier detection and aggressive treatment of the late complications occurring in the remainder of the diseased aorta is necessary to improve long-term survival after the Bentall operation.

Actuarial Analysis↗

[Evaluation of early and late results of open heart surgery in 74 patients 70 years of age and older].

A retrospective analysis of 12-year experience with open heart surgery in 74 patients 70 years of age and older during 1979 and 1990 was performed. The subjects consisted of 51 patients with coronary artery disease, 11 with acquired valvular disease, 2 with congenital heart disease and 10 with combined heart disease. Operative mortality was 9% and late mortality, 16%. The incidence of low output syndrome and respiratory failure were significantly high postoperatively. Multivariate analysis demonstrated that determinants of operative prognosis were postinfarction ventricular septal perforation, aortic cross-clamp time, preoperative renal dysfunction and coronary-valvular combined disease. Actuarial survival rate at 5 years was 89% for an entire series, which was favorably compared with age-sex matched population.

Age Factors↗

[Tracheobronchoplasty for functional restoration].

We have experienced 10 cases of terminal mediastinal tracheostomy (TMT), 7 cases of laryngotracheal anastomosis with subtotal resection of cricoid cartilage (LTT), 5 cases of sleeve or wedge segmentectomy (SS, WS) for lung cancer with low pulmonary function, and 5 cases of carinal reconstructions (CR) with one stomal anastomosis between left lobar bronchus and trachea after partial resection of carina for tuberculous stenosis of left main bronchus. Modified TMT which stomaplasty was constructed with cervical and anterior chest skin flap different from primary procedure by Grillo was performed in 3 cases without innominate artery rupture nor cicatricial stomal stenosis. LTT by Pearson's procedure caused telescoped anastomosis. Pulmonary function was reserved in all 5 cases of SS and WS. Salvaged left lung by single stomal CR in the cases of tuberculous stenosis functioned well. Two different approaches for subaortic arch anastomosis, namely Pull-down and Pull-up, were proposed in single stomal CR. Pull-down provided excellent exposure of the carina without sacrifice of intercostal arteries. Indication of plasty was extended by TMT and LTT for upper limits of airway resection, SS and WS for limited operation against lung cancer, and single stomal CR for tuberculous stenosis of left main bronchus.

Bronchi↗

[The long-term results of patients over 70 years old after coronary artery bypass surgery].

We have assessed the long-term results of heptagenerians after isolated coronary artery bypass surgery from 1979 to 1989 in 32 patients over 70 (mean 72) years old using actuarial techniques. In these patients, the long-term results could not be properly assessed because many other factors other than cardiac events influenced their survival. Accordingly, we compared our subjects with the general population matching the operative age and sex characteristics from life tables (= matched population). There was no operative mortality. The 5 year and 9 year survival rates were 93% and 31%. In the matched population, the 5 year and 9 year survival rates were 81% and 59%. The survival rate between the two groups was not significantly different. We concluded that the long-term results of coronary artery bypass surgery in patients over 70 years were similar to those of the matched population. Therefore, coronary artery bypass surgery should be offered to older patients for usual indications.

Aged↗

A five-year appraisal and hemodynamic evaluation of the Björk-Shiley Monostrut valve.

Two hundred forty-four Björk-Shiley Monostrut valves were implanted in 225 consecutive patients from October 1983 to December 1988. Aortic valve replacement was performed in 90 patients, mitral valve replacement in 118, and double valve replacement in 16 patients. One patient had tricuspid valve replacement. There were 100 female patients and 125 male patients with a mean age of 54 years (range 2 to 71 years). Present data were completely available for all patients. The cumulative follow-up was 541 patient-years with a mean of 2 years, 5 months. The closing date for follow-up was July 1989, and the closing interval was 2 months. The early mortality rate was 3.1%, and the late mortality rate, 3.1%. The 5-year survival rate was 88% +/- 2.0%: 87% +/- 3.0% for aortic valve replacement, 91% +/- 3.3% for mitral valve replacement, and 75% +/- 9.6% for double valve replacement. The actuarial rates of freedom from thromboembolism at 5 years were 93% +/- 3.2% for aortic, 96% +/- 1.4% for mitral, and 94% +/- 6.1% for double valve replacement. There were no instances of structural valve deterioration. Actuarial rate of freedom from valve-related morbidity and mortality was 86% +/- 2.0% at 5 years: 86% +/- 9.5% for aortic, 87% +/- 3.3% for mitral, and 75% +/- 7.3% for double valve replacement. Effective valve areas (average) of 12 mitral and 12 aortic valve prostheses were calculated at rest and during bicycle exercise: 2.4 cm2 at rest and 2.8 cm2 during exercise in 27 mm aortic valves, 2.4 cm2 at rest and 3.0 cm2 during exercise in 25 mm aortic valves, 2.0 cm2 at rest and 2.4 cm2 during exercise in 27 mm mitral valves, and 2.6 cm2 at rest and 2.5 cm2 during exercise in 29 mm mitral valve. On the basis of our follow-up period of 5 years, we have judged the Björk-Shiley Monostrut valve reliable, with a low incidence of valve-related morbidity and with acceptably satisfactory hemodynamic characteristics at rest and during exercise.

Adolescent↗

[Anesthetic and postoperative management of a patient with Gilbert's syndrome and another with Dubin-Johnson syndrome].

Anesthesia and postoperative management of a patient with Gilbert's syndrome and one with Dubin-Johnson syndrome is reported. The former patient underwent open heart surgery and the latter had a partial resection and reconstruction of the esophagus. The anesthetics used in these two cases were fentanyl and nitrous oxide. The patient with Gilbert's syndrome had remarkable perioperative complications. On the other hand, the patient with Dubin-Johnson syndrome developed conjugated hyperbilirubinemia after the 2nd postoperative day. On the 5th postoperative day, his serum and direct bilirubin levels were elevated to 19.3 mg.dl-1 and 12.8 mg.dl-1, respectively. Therefore, we had to perform daily plasmapheresis on this patient for four days. Thereafter, his serum bilirubin level decreased gradually.

Adolescent↗