Comparison of transfer and distribution of technetium and rhenium in radish plants from nutrient solution

Tracer experiments were carried out to compare the plant uptake behavior of Tc and Re from nutrient solutions. Radish plants, transplanted to nutrient solution including various tracers, showed the same uptake and distribution of ^95mTc and ¹⁸³Re. The trend was the same when the ⁹⁹Tc and stable-Re concentrations were increased in nutrient solution. The behavior of other elements was different from that of Tc and Re. These findings suggest the possible use of Re as the chemical analogue of Tc in soil solution to plant uptake experiments.     

Angiographic studies on the effects of a novel calcium antagonist AE0047 on cerebral arteries in dogs, with special reference to the preventive effects of AE0047 on cerebral vasoconstriction induced by endothelin

AE0047, a novel calcium antagonist, has mild and long-acting hypotensive effects. This drug also has more selective dilating action on cerebral arteries than on other systemic ones. We studied the cerebral vasodilatative effects of AE0047 by means of vertebral angiography in anesthetized dogs. Vertebral blood flow (VBF) was significantly increased by 91, 139 and 132% in 10, 30 and 60 min after intravenous administration of AE0047 at 30 micrograms/kg, respectively. No difference in vasodilating action was observed among basilar, posterior communicating, middle cerebral and internal carotid arteries. In basilar artery, the dilatative rate was about 30% between 10 and 60 min after injection of AE0047. Following intravertebral administration of endothelin at 100 pmol/kg, small vessels of the cerebral artery were constricted, and VBF was gradually decreased. AE0047 eliminated the vasoconstriction and increased VBF. Moreover, the vasoconstrictive effect of endothelin was prevented by pre-treatment of AE0047. These results indicate that AE0047 has potent vasodilating and spasmolytic actions on cerebral arteries.     

Inhibitory effects of calmodulin antagonists on isoproterenol- and dibutyryl cyclic AMP-stimulated amylase release from rat parotid acinar cells

The effects of three calmodulin antagonists on rat parotid amylase release were investigated in vitro using a dispersed acinar cell preparation. The potent calmodulin antagonists, trifluoperazine (TFP) and N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7), inhibited both 1 microM isoproterenol (ISO)- and 1 mM dibutyryl cyclic AMP (DBcAMP)-stimulated amylase release in a dose-dependent manner at concentrations of 25-100 microM. The IC50 values for the ISO-stimulated amylase release were 22 microM with TFP and 42 microM with W-7, and the values for the DBcAMP-stimulated release were 25 microM and 48 microM, respectively. The weak calmodulin antagonist, N-(6-aminohexyl)-1-naphthalenesulfonamide (W-5), caused only slight inhibition at a concentration of 100 microM. These calmodulin antagonists only had a very small effect on the spontaneous release of lactate dehydrogenase. The results suggest that the calcium-calmodulin system may play a role in the exocytotic process of amylase release from the rat parotid gland.     

Mixed H2/H∞ control with pole placement in a class of regions

The problem of mixed H₂/H_∞ control with pole placement is considered for linear time-invariant systems. This is the problem of determining a controller for linear time-invariant systems which minimizes the H₂-norm of a certain closed-loop transfor function subject to an H_∞-norm constraint on another closed-loop transfer function and an additional constraint on the location of the closed-loop poles in the complex plane. An optimization problem is posed for the pole-constrained H₂/H_∞, problem in such a way that the objective function is expressed as a weighted sum of the actual H₂ cost and its upper bound. A necessary condition for the optimization problem is derived via the Lagrange multiplier technique. The condition involves a set of highly coupled equations. By sacrificing the H₂ performance, an alternative optimization problem is posed in order to simplify the necessary condition. An iterative algorithm for solving the coupled equations arising in the necessary conditions is proposed and numerical examples are presented.     

A case of multiple leiomyomatous lesions of the lung: An analysis of flowcytometry and hormone receptors

A 36 year old woman was admitted to our department because of a chest X-ray which showed multiple developing shadows. She underwent bilateral exploratory thoracotomies and a total 5 tumors were resected and pathologically diagnosed as benign metastasizing leiomyoma, the largest of which was positive for the progesterone receptor and negative for the estrogen receptor. A histogram of this tumor using a flow cytometer showed a diploid pattern and 4.6 percent of the S phase which was not more than that of a leiomyoma of the uterus from another patient. Two months later, she underwent a hysterectomy and bilateral salpingo-oophorectomy for treatment of the positive progesterone receptor in the pulmonary lesions. The resected uterine myoma and normal myometrium showed positive estrogen and progesterone receptors. For the subsequent 28 months she has been free of any further symptoms. Benign metastasizing leiomyoma of the uterus is a rare disease and very interesting because of its histological benignity and hormonal dependency. However, according to the literature, it is often confused in entity due to the fact that normal lung tissue also possesses hormone receptors. Considering our data on hormone receptors, it is rational to think that multiple leiomyomatous lesions in the lung should only be diagnosed as benign metastasizing leiomyomas when they possess positive estrogen and progesterone receptors.     

Internal jugular vein catheterization in infants undergoing cardiovascular surgery: an analysis of the factors influencing successful catheterization.

Central venous catheterization for pressure monitoring and drug administration is often important in the anesthetic management of infants undergoing cardiovascular surgery. We examined the effects of patient age, weight, and central venous pressure and the experience of the anesthesiologist on the rate of successful catheterization and catheterization time of the internal jugular vein (IJV) in a prospective study. We studied 106 infants undergoing IJV catheterization for cardiovascular surgery over a 7-mo period at our institution. We catheterized the IJV by the high approach. The direct venipuncture or the Seldinger method was used according to the patient's weight. Overall successful catheterization rate was 97.2%, and the average catheterization time was 353 +/- 21 s (mean +/- SEM). Complications included arterial puncture in 12 cases (11.3%), hematoma formation in four cases (3.8%), and catheter malposition in two cases (1.9%), but pneumothorax was not observed. When a patient was younger than 3 mo or weighed less than 4.0 kg, successful catheterization rate decreased significantly to 81.3% and 78.6%, respectively. Catheterization time was inversely correlated with both age and weight, whereas central venous pressure did not affect either successful catheterization rate or catheterization time. We were unable to demonstrate that the experience of the anesthesiologist plays a significant role in the success or complication of the catheterization procedure. Our results indicate that IJV catheterization by the high approach is a reliable and useful technique in infants, and that the weight and age of the patient significantly influence the rate of successful catheterization.     

The relation between EEG and mental development following cardiac surgery performed under simple deep hypothermia in children

In order to assess the accuracy of electroencephalography (EEG), in children who have undergone cardiac surgery under simple deep hypothermia, the relation between IQ or schoolwork achievement and the duration of circulatory arrest was investigated in 75 such children. Abnormal preoperative EEG's were found in 16 per cent of the children while abnormal postoperative EEG's were found in 17 per cent. The children were divided into 4 groups, according to pre- and postoperative EEG results. Schoolwork achievement scores ranged between 3.0 and 3.2, the difference among the groups being insignificant. Moreover, no significant shift in IQ was found among the groups. Finally, regarding the number of children who were able to go on to a higher level of education, including high school the college or university, again no significant differences were found among the 4 groups. In a comparison with the number of such children in neighboring Nagasaki prefecture able to continue on to a higher level of education, no significant differences were seen either. The findings and statistics of this investigation therefore indicate that pre- and postoperative EEG's are not always a reliable reference for assessing the prognosis of cerebral activity.