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T Honna

Publications and source records attributed to T Honna.

54 records · Page 3Linked to original sources

[Diagnosis and treatment of Wilms' tumor].

Recent advances in the diagnosis and treatment of Wilms' tumor are reviewed. Our study disclosed that principal clinical and pathological features of Wilms' tumor are as follows: (1) It occurs in young infants and children under 5 years of age; (2) It is frequently associated with other congenital anomalies; (3) Deletion of a portion of short arm of chromosome 11 can be closely related to the tumor genesis of nephroblastoma; (4) The occurrence of distant metastases is rare at diagnosis; (5) Differential diagnosis between Wilms' tumor and neuroblastoma is occasionally quite difficult; (6) There is no good tumor marker specific to Wilms' tumor; and (7) Two-year survival rate is about 90% at present.

Antineoplastic Combined Chemotherapy Protocols↗

Norepinephrine levels in the coronary sinus in patients with cardiovascular diseases at rest and during isometric handgrip exercise.

In order to evaluate cardiac sympathetic nerve activity, plasma norepinephrine levels in the coronary sinus (NECS) and in the artery (NEA) were determined in 24 subjects with cardiovascular diseases and in six with functional murmur. The resting NECS was greater than NEA in 14 subjects with normal left ventricular end-diastolic pressure (LVEDP) (p < 0.001) and/or in 22 with normal cardiac index (p < 0.04), whereas NECS was not significantly different from NEA in the remaining patients with elevated LVEDP and/or with reduced cardiac index. Isometric handgrip exercise increased both NECS and NEA (p < 0.001). When subjects were divided into two groups according to the slope of the ventricular function curve (delta stroke work index/delta LVEDP), NECS during exercise was greater then NEA in the group having slopes of 1.0 or more (p < 0.01), but neither values significantly differed in the group with slopes of less than 1.0. In the latter group, cardiac NE overflow rat calculated from the difference between NECS and NEA multiplied by coronary sinus plasma flow, was significantly less than that of the former group before and during handgrip (p < 0.05 and p < 0.01, respectively). These results suggest that cardiac norepinephrine release into the coronary sinus is reduced in patients with impaired cardiac function.

Adolescent↗

Cineventriculographic analysis of left ventricular dynamics during sustained handgrip exercise.

In order to evaluate the effect of handgrip on left ventricular dynamics, cineventriculography was performed in 16 patients with heart disease and 5 normal subjects at 30% of maximal voluntary contraction. No patient had ventriculographic evidence of asynergy or valve regurgitation. During exercise, left-ventricular end-diastolic volume (LVEDV) insignificantly increased, left ventricular end-systolic volume (LVESV) decreased, and hence stroke volume (SV) and ejection fraction (EF) rose in the normal group, while in the patient group a similar change in LVEDV was associated with increased LVESV, resulting in unchanged SV and decreased EF. It is notable that during exercise LVEDV increased in both groups, despite a shortened diastolic filling period. Mean velocity of fiber shortening (mean VCF) increased in the normal group and remained unchanged in the patient group. The changes in mean VCF during exercise were correlated with the alterations in SV and EF (r=0.46, p less than 0.05 and r=0.90, p less than 0.001), respectively). These data signify that an increased afterload induced by handgrip leads to an enhanced left ventricular myocardial contraction in addition to an increase in preload in the normal group, while the Frank-Starling mechanism is mainly utilized in the patient group.

Adolescent↗

Alpha-fetoprotein in infantile obstructive jaundice in comparison with the normal ranges.

In an attempt to study the diagnostic value of alpha-fetoprotein (AFP), serum AFP concentrations were measured by radioimmunoassay in 34 neonates and infants with obstructive hepatobiliary diseases and the results were compared with the normal ranges of AFP at this age. Eighteen of 24 infants with biliary atresia and four of six infants with neonatal hepatitis had raised AFP values. In only one of four infants with choledochal cyst, did the AFP value exceed the normal range. In 10 older children with this lesion, AFP was normal. Serum AFP concentrations in biliary atresia did not correlate with the serum bilirubin, s-GOT, s-GPT, anatomic type of the lesion or postoperative bile flow. From these observations, it would appear that the elevation of AFP in infantile cholestasis is unrelated to underlying diseases except in case of alpha 1-antitrypsin deficiency. Serum AFP concentrations in neonates with physiological jaundice, were seldom elevated, and showed a good correlation with serum levels of total bilirubin. Possible mechanisms causing this elevation of AFP may be different from those involved in infantile cholestasis.

Aging↗

Plasma norepinephrine concentration in the coronary sinus in cardiomyopathies.

In order to evaluate the cardiac sympathetic nerve tone in cardiomyopathies, plasma norepinephrine concentration in the coronary sinus (NE(CS)) and artery (NE(A)) was measured by THI method in five patients with the hypertrophic type (HCM) and in seven with the congestive type (CCM); six patients with functional murmur served as controls. NE(CS) was 182 +/- 39 ng/liter (SEM) in HCM, 288 +/- 47 in CCM, and 306 +/- 65 in controls. The NE(CS) - NE(A) difference (delta NE) was 9 +/- 22 ng/liter in HCM, -57 +/- 34 in CCM, and 81 +/- 29 in controls. Norepinephrine overflow into the coronary sinus,which was calculated by multiplying coronary sinus plasma flow by delta NE, was 0.54 +/- 0.86 ng/min/100gm, -2.81 +/- 1.47, and 3.73 +/- 1.77, respectively. Norepinephrine overflow and delta NE were significantly lower in CCM than in controls. The results suggest than an excessive sympathetic discharge does not exist in HCM and that cardiac sympathetic activity is reduced in CCM.

Adolescent↗

Cineventriculographic analysis of the ventricular septal motion during stimulation of various pacemaker sites.

By means of cineventriculography, contraction pattern of the ventricular septum was studied during electrical stimulation of the right atrium (RA), outflow tract (RVO) and apex (RVA) of the right ventricle and apex (LVA) and lateral wall (LVL) of the left ventricle. RA pacing produced a monophasic shortening of the septal hemiaxes after initial lengthening for about 40 msec from R wave of ECG. In contrast, ventricular stimulation near the septum (i.e. RVO, RVA and LVA) resulted in a biphasic and decreased contraction of the septal wall, in which an early preejection shortening was followed by a brief lengthening and second shortening. LVL pacing showed a monophasic and increased contraction of the septal wall. The biphasic motion of the septal wall was likely to be related to the abnormal mechanical contraction caused by the abnormal conduction sequence of ventricular depolarization. On the other hand, the lateral wall demonstrated a biphasic and decreased contraction during LVL pacing, and a monophasic and increased contraction during RVO, RVA and LVA pacing. Thus, the biphasic and diminished contraction at the site of electrical stimulation was compensated by the monophasic and forceful contraction of the contralateral wall. It is considered that the ventricular septum plays an important functional role in regulation of cardiac performance.

Animals↗

Effects of pacing location on coronary circulation in dogs.

In 13 open chest dogs, the right atrium and various ventricular sites (i.e. the inflow and outflow tracts and apex of the right ventricle, apex and lateral wall of the left ventricle) were stimulated electrically at a given rate, ranging from 140 to 210 per min. Coronary circulation and cardiodynamics in response to ventricular pacing were compared with those to right atrial pacing at equivalent heart rate. Stimulation of the ventricle except lateral wall of the left ventricle produced no significant changes in coronary sinus blood flow and myocardial oxygen consumption despite decreased blood pressure and cardiac output. The minor change of coronary sinus blood flow was related to the decrease in coronary vascular resistance. Oxygen content of coronary sinus blood decreased during ventricular pacing, while arterial oxygen saturation remained constant. The response of coronary circulation to ventricular pacing did not differ essentially at faster and slower heart rates. It was considered that when stimuli were applied to the ventricular surface, the relatively constant myocardial oxygen consumption in the presence of lowered cardiac performance was attributed to the asynchrony of fractionate contractions of the ventricular muscle.

Animals↗

Effects of isometric handgrip exercise on coronary sinus blood flow in idiopathic cardiomyopathy.

Coronary sinus blood flow (CSBF) was measured by the dye dilution method in 18 patients with idiopathic cardiomyopathy including 13 with hypertrophic type and 5 with congestive type, and the capacity for increasing CSBF in response to handgrip exercise was studied in 14 patients. CSBF at rest ranged from 41 to 236 ml/min/M2. Average CSBF of 114 +/- 12 ml/min/M2 (112 +/- 14 in hypertrophic type and 119 +/- 25 in congestive type) was significantly larger than control value of 77 +/- 6 presented previously (p less than 0.01). Handgrip exercise at 30% maximal effort for 3 min resulted in the increase in CSBF, averaging 23 +/- 8 ml/min/M2 (22 +/- 8%). However, in about one-half of cases, the percent increase in CSBF was much smaller than the percent increase in effort index which represents myocardial oxygen demand. The change of CSBF was not correlated with the changes of left ventricular systolic pressure, cardiac output, and stroke work. The diminished response of CSBF to isometric handgrip exercise was ascribed to the decreased coronary vascular reserve in this disorder.

Adolescent↗

Plasma catecholamine levels in the coronary sinus, aorta and femoral vein of subjects undergoing cardiac catheterization at rest and during exercise.

Plasma catecholamine (CA) levels in the coronary sinus (CS), aorta (Ao) and femoral vein (fv) were simultaneously measured in 22 patients with various heart diseases at rest and during handgrip exercise (IHG). The mean resting levels of plasma norepinephine (NE) in CS, Ao and FV were 359 +/- 49 (SEM) pg/ml, 290 +/- 27 and 234 +/- 24, respectively. The corresponding values of epinephrine (E) were 127 +/- 18 pg/ml, 186+/- 30 and 97 +/- 11, respectively. The E values in Ao were significantly greater than those in CS and in FV (p less than 0.05). IHG exercise induced an obvious elevation of plasma CA levels in every portion of the circulation studied. The mean increments of NE concentration were 81%, 54% and 67% of the resting levels at CS, Ao and FV, respectively, while IHG induced elevation of E were 70% of the resting values at each portion studied. Significant correlations were observed between individual CA concentrations in CS and in Ao, and also between those in Ao and in FV at rest. Under raised sympathoadrenal conditions, however, individual values of NE in CS failed to correlate signficantly to those in Ao and in FV, respectively. The NE output from CS was limited to only 3% and 5% of those in Ao at rest and during IHG, respectively. An actual mean increment of NE on its passing through the coronary circulation was only 2% or less of NE output in ao at both stages. It appears, thus, to be untenable that the cardiac tissue is one of the major source of circulating CA at physiological condition. From these reasons, the direct measurement of NE levels in CS may be mandatory, when plasma CA assay is designed for the purpose of studying the role of the sympathetic nerve activity in the regulation of cardiac function.

Adolescent↗

Effects of varying pacemaker sites on left ventricular performance.

The hemodynamic effects of the site of the artificial cardiac stimulation were studied in 17 open chest dogs. The right atrium and five ventricular sites (the inflow and outflow tracts and apex of the right ventricle, apex and lateral wall of the left ventricle) were stimulated electronically at a given rate, ranging from 130 to 190 per min. When cardiac performance during ventricular pacing was compared with those during right atrial pacing, the former uniformly caused a diminution of cardiac output and systemic blood pressure, without reduction of left ventricular end-diastolic pressure. Ventricular function curves, in which left ventricular stroke work was related to left ventricular end-diastolic pressure, shifted downwards and to the right during ventricular pacing. Stimulation frequency did not alter these variables. It was considered that the left ventricular dysfunction in ventricular pacing resulted from the absence of atrial contribution to ventricular filling, mitral regurgitation present and asynchronous ventricular contraction. No significant difference of cardiac performance was demonstrated by changing the site of ventricular pacing, suggesting that the mode of ventricular depolarization itself was not relevant to a decrease in cardiac performance.

Animals↗

Renin production in congenital mesoblastic nephroma in comparison with that in Wilms' tumor.

The case of an infant with congenital mesoblastic nephroma and associated reninism is presented. The patient was a 39-day-old boy who presented with a left abdominal mass and mild hypertension (112/70 mm Hg). Both plasma renin activity (PRA) and plasma total renin concentration (PTRC) were elevated; the PTRC value of 1458 pg/mL of this case was the highest we had seen in patients with childhood renal tumors. The tumor was successfully removed and histologically confirmed as a congenital mesoblastic nephroma (cellular variant). The patient's PRA and PTRC returned to normal after nephrectomy. Indirect immunoperoxidase staining showed renin localized predominantly in the juxtaglomerular apparatuses adjacent to the glomeruli entrapped by the tumor. No positive staining was seen in the tumor cells. These findings indicate that the entrapped glomeruli may play a significant role in producing renin. More important, PTRC was extremely high compared to the moderate increase of PRA and to the mild elevation of blood pressure. The mechanism of renin production by childhood renal tumors is discussed, and the importance of studying inactive renin and total renin is emphasized.

Humans↗

Reduced response of cardiac norepinephrine release to isometric handgrip exercise in heart failure.

In order to evaluate the relation of cardiac norepinephrine (NE) release to left ventricular function, blood was taken simultaneously from the coronary sinus (CS) and the aorta (A) in 19 patients with heart diseases, at rest and during isometric handgrip exercise (IHG) at 30% of their maximal contraction. Plasma NE was analyzed by Renzini's THI method. The concentrations of plasma NE at rest were 397 +/- 66 (S.E.M.) ng/liter in CS and 292 +/- 50 in A. IHG significantly increased NE to 578 +/- 88 in CS and to 462 +/- 85 in A (p less than 0.001). Estimated NE release from the heart (deltaNE = NECS - NEA) correlated inversely to left ventricular end-diastolic pressure at rest (r = -0.520, p less than 0.05) and during IHG (r= -0.689, p less than 0.01). The changes in deltaNE induced by IHG correlated to the slope of the left ventricular function curve (r=0.618, p less than 0.01). It is concluded that the response of cardiac NE release to exercise is reduced in patients with depressed cardiac function.

Blood Pressure↗