The first pediatric Japanese case to undergo heart transplantation in the Utah Cardiac Transplant Program in the United States

A seven-year-old girl underwent heart transplantation because of progressive congestive heart failure resulting from familial dilated cardiomyopathy. Her parents were second cousins to each other and her brother had died of dilated cardiomyopathy. Her symptoms of congestive heart failure began four months before the transplantation and became gradually worse. Left ventricular ejection fraction was 10 to 20% echocardiographically, and mitral and tricuspid valve regurgitation were present. Her condition of NYHA IV was not improved by treatment with dobutamine infusion and isosorbide dinitrate. She was transported to the Primary Children's Medical Center in Utah, USA, on July 22, 1991 in critical condition to undergo heart transplantation. Despite treatment with amrinone and additional catecholamines, she became semicomatose due to ischemic liver injury on July 24, 1991. A donor became available on July 25, 1991, and the transplantation was performed. Cardiac ischemic time was 97 min. Although she had transient OKT3 monoclonal antibody-related encephalopathy on her fifth postoperative day, she recovered normally. She had moderate rejection on the 20th postoperative day and mild rejection on the 79th and 149th postoperative days. She has had no significant infectious diseases. The baseline examination performed three months after heart transplantation revealed no abnormal findings on her coronary arteriogram. She returned to Japan and has been attending elementary school. The annual examination of her transplanted heart showed neither stenosis nor occlusion in her coronary angiogram. She has been receiving cyclosporine, azathioprine, and a low dose of prednisone as an immunosuppressive regimen. If she does not exhibit rejection, the use of steroids will be decreased or discontinued.

Binocular neuronal responsiveness in Clare-Bishop cortex of Siamese cats

Retinotopy and binocular responsiveness were studied extracellularly in a total of 278, 61, 110 and 275 cells sampled in areas 17, 18, 19 and Clare-Bishop (CB) of Siamese cats. The misalignment of the visual axes of the two eyes was determined by the pupil reflex method in the behaving animal. The recording sessions were conducted under N2O anesthesia, supplemented with continuous infusion of short-lasting anesthetics (Saffan, Glaxo) and muscle relaxants (Gallamine triethiodide) using two types of visual stimulators presenting two-dimensional (2D) motion stimuli and the visual cues for three-dimensional (3D) motion. All of the nine Siamese cats demonstrated Boston type retinotopic abnormalities in all of cortical areas 17-19 and CB. Very few binocular cells were present in areas 17-19 and the posterior (A1-P2) CB but they were numerous in most of CB (A9-4). A significant fraction (36/78) of binocular cells in the major CB of the Siamese cats demonstrated similar response selectivity to that reported in normal CB cortex for stimulation with the 3D motion cues under both null disparity and strabismic conditions (binocular receptive fields for two eyes were optically superposed or separated by the strabismic angles estimated in the individual animals). These findings indicate that the binocular signals converging to the CB cells through different pathways (signals coming from the contralateral eye via the ipsilateral hemisphere including the interlaminar nucleus and areas 17-19, and commissural signals from the ipsilateral eye via the contralateral areas 17-19 and CB) were integrated to yield useful information for the recognition of 3D motion, and that the major CB is an actual site of binocular integration at least in Siamese cats, rather than being merely a reflection of the information processing before the CB cortex.

Functional differentiation between the anterior and posterior Clare-Bishop cortex of the cat

A total of 783 cells were studied extracellularly in anterior (A10-13), posterior (A4-8), and intermediate regions (A8.1-9.9) of Clare-Bishop (CB) cortex of the cat, which were defined according to the anteroposterior coordinate of the stereotaxic axis and probably corresponded to the antero- (AMLS), postero-medial lateral suprasylvian cortex (PMLS), and the border region between the two subareas, respectively. The study was conducted under N2O anesthesia supplemented with continuous infusion of short-lasting anesthetics (Saffan, Glaxo or Etomidate, Janssen), using three types of visual stimulators presenting two- (2D) and three-dimensional (3D) motion stimuli, and visual cues contained in the 3D motion. Neuronal responsiveness was essentially similar between the anterior and posterior CB subdivisions. Both areas contained 1) AP, 2) RC and 3) FP cells, selectively responsive to approaching, recessive and fronto-parallel motion, and 4) NS and 5) U cells, nonselectively responsive and unresponsive to any of these motions. However, a quantitative difference was found: 1) In the posterior CB the FP cell population was the largest, and the frequency reduced in the order of AP, NS, RC and U cells, while the largest population in the anterior CB consisted of the AP and U cells, and the frequency reduced in the order of FP, RC and NS cells. 2) 3D (AP and RC) cells in the posterior CB responded preferentially to approaching motion at a distal range, while those in the anterior CB preferred motion at a proximal range. 3) The 3D cells in the posterior CB were more sensitive to the motion cue and demonstrated lower thresholds for the size cue than the anterior CB cells. 4) The anterior CB cells generally demonstrated high-pass velocity tuning (cut-off around 10 degrees/s) for monoclonal 2D stimulation, while the posterior CB cells demonstrated a broad band-pass tuning (4-120 degrees/s). These findings suggest functional differentiation in neuronal representation of 3D motion signals between the two subdivisions of CB cortex.

Choreoathetoid movements associated with a spleno-renal shunt

A 73-year-old woman without liver cirrhosis developed choreoathetoid movements of the limbs due to portal-systemic encephalopathy. A prominent spleno-renal shunt was demonstrated by non-invasive methods (abdominal computed tomography and sonography) as well as arterial portography. The choreoathetoid movements were improved by a protein-restricted diet and administration of lactulose. A portal systemic shunt should be considered when investigating choreoathetosis, even in patients without liver cirrhosis.

Electrophysiological and morphological correlates in the development of visual cortical circuitry in infant kittens

Geniculate axons in cat visual cortex establish excitatory connections with cortical cells in supragranular and granular layers at birth. They are localized to the granular layer for the first month after birth. Retraction of geniculocortical synapses parallels axonal extension of spiny stellate cells to the supragranular layer and establishment of synapses for intracortical transmission.

Responsiveness of Clare-Bishop neurons to visual cues associated with motion of a visual stimulus in three-dimensional space

Photic responsiveness of cells in the medial bank of the lateral suprasylvian cortex (Clare-Bishop area) was studied using a three-dimensional visual stimulator that reproduced two visual cues (motion disparity and change in size) for perception of three-dimensional motion of a visual stimulus. About one third of them (48/148) were selectively responsive to motion disparity corresponding to approaching (AP cells, n = 30) or recessive motion (RC cells, N = 18), another half to motion of retinal images in the same direction between the two eyes corresponding to fronto-parallel motion (FP cells, n = 75), and the remaining cells were rather equally responsive to these types of stimuli (NS cells, n = 25). More than a half of the AP (19/30) or RC (11/18) cells were also responsive to increase or decrease in stimulus size, respectively, and they were optimally activated by a combination of the motion and size stimuli while relatively few FP and NS cells were sensitive to change in stimulus size. These findings indicate that the Clare-Bishop cells encode three-dimensional motion on the basis of photic responsiveness to the motion and size cues.

[Dependence of scattered Mn K alpha / K beta X-ray intensity ratio on the scatterer materials]

The K alpha / K beta ratio of Mn KX-rays scattered by metallic samples changed remarkably with the geometry between the sample and the (55)Fe source-Si(Li) detector system. On the contrary, this intensity ratio changed little in the cases of non-metallic scatterer samples such as lucite or mylar. This difference is interpreted as due to the occurrence of strong or weak interference in the coherent scattering photons.

[Contribution of 210Bi beta-ray induced bremsstrahlung to the emission of Pb-KX-rays observed in the lead shielded gamma-ray background spectrum (author's transl)]

Observation of gamma-ray background has been done by using a Ge(Li) semiconductor detector when it was placed inside the lead shielding material. With the aid of a very simple model calculation, the concentration of 210Pb radioisotope embedded in the lead material has been estimated to be 0.1-0.4 (Bq/Pb-g) (3-12 (pCi/Pb-g). The origin of Pb-KX-ray emission, the highest peak in the background spectrum, has been investigated by comparing the 210Pb-47 keV gamma-ray and Pb-KX-ray peak counts. As the results, about 50 +/- 30% of Pb-KX-ray production is estimated to be due to the Pb-K shell photoionization which is induced by the bremsstrahlung of 210Bi beta-ray.