Cortical potential shifts preceding voluntary movement are normal in parkinsonism

We have recorded movement-related cortical potentials (MRCPs) preceding voluntary finger extension from 10 subjects with Parkinson's disease and compared the results with those obtained from groups of young and old subjects described in the previous paper in this volume (Barrett et al. 1986). Three separate potential shifts preceding voluntary movement were identified in the wave forms of all subjects. There were no differences between the healthy aged subjects and those with Parkinson's disease in terms of the onset latencies or gradients of these potential shifts. The potential shift associated with the final phase of preparation (NS') was significantly less widespread over central scalp for the older subjects compared with the young. Equivalent results for a 35-year-old subject with Parkinson's disease were indistinguishable from those obtained from the young subjects suggesting that this restriction in the distribution of NS' is related to normal ageing rather than the disease process of parkinsonism. There were no differences within the group of parkinsonian subjects with respect to potential shifts associated with differing degrees of movement disability between the two hands. Our results contradict previous reports of abnormal MRCPs in Parkinson's disease (Deecke et al. 1977; Deecke and Kornhuber 1978; Shibasaki et al. 1978). We attribute this primarily to an improved method of recording MRCP which compensates for time jitter between EMG onset and the production of a trigger pulse for averaging (Barrett et al. 1985).     

Immunohistochemical localization and dynamics of paraquat in the stomach and esophagus of rats

Summary The dynamics of paraquat in the stomach and esophagus of rats were demonstrated using immunohistochemical techniques. The Rats were killed 3 h, 12 h, 24 h, 3 days, 7 days and 10 days after intravenous administration of paraquat. In the stomach, paraquat was localized in the epithelial cells between 24h and 10 days after injection, whereas in the esophagus, paraquat was localized in epithelial cells and the lamina propria mucosa between 12 h and 10 days after administration. Although these findings were similar to those observed in the intestine of rats, no clear changes in the distribution of paraquat with time were observed; suggesting that the stomach and esophagus are important reservoirs for the redistribution of paraquat.     

The effect of human SOD on the survival rate in rats with temporary splanchnic ischemia

The accumulation of oxygen free radicals is reported to occur in the organs subjected to temporary ischemia followed by reperfusion, resulting in the fatal outcome of the animals. The effects of human SOD, a representative scavenger of oxygen free radicals, on the survival rates were investigated in the rats with temporary splanchnic ischemia. The temporary ischemia was induced by the occlusion of anterior mesenteric and celiac arteries for 30min under anesthesia. Prior and after treatment with 2mg/100g of human SOD, iv or sc, produced significant improvements in survival rates. Human SOD, cloned from human placenta DNA and expressed in microorganisms, has extreme homogeneity. The results suggest the possible introduction of human SOD into clinical field as an effective scavenger of oxygen free radicals.(Ogawa R, Bitoh H, Ohi Y: The effect of human SOD on the survival rate in rats with temporary splanchnic ischemia. J Anesth 2: 41–45, 1988)     

Treatment of delayed brain injury after pituitary irradiation

Treatment for delayed brain injury after pituitary irradiation is discussed. Six cases with delayed brain injury were treated with a combination of dexamethasone or betamethasone, with heparin, glycerol, dextran 40 and some vasodilators. Two cases with temporal lobe syndrome were treated in the early stages of brain injury for a period of over 12 months were almost completely cured, another two cases with chiasma syndrome were treated in the relatively late stages, showed a partial improvement. One case which was irradiated 120 GY during 13 years did not improve. The final case treated with steroids for a short period also resulted in failure and the patient underwent an operation for the removal of the necrotic mass three years after the radiotherapy. Steroid therapy started in the early stages of brain injury after irradiation for over the 12 months is thought to be effective. Heparin therapy was also effective in one out of three cases, but in one of the cases subarachnoid hemorrhage from a traumatic aneurysm occurred during the therapy. In an acute phase, showing edematous change of the injured brain, the administration of glycerol is also thought to be useful. But the effectiveness of the other medicines containing some vasodilators was obscure or doubtful. We propose the following: (1) A meticulous observation is essential for the patients who received high doses of irradiation to diagnose brain injury in the early reversible stage. (2) Steroids should be given immediately in this reversible stage of brain injury before the irreversible "necrosis" occurs. (3) Steroids should be maintained for a long period over 12 months.(ABSTRACT TRUNCATED AT 250 WORDS)     

Use of a Paracorporeal Pneumatic Ventricular Assist Device for Postoperative Cardiogenic Shock in Two Children with Complex Cardiac Lesions

Pneumatic ventricular assist device (VAD) was utilized for cardiogenic shock after intracardiac operation in two children with complex cardiac anomalies based with single ventricle. In the first case (a 10-year-old), after a modified Fontan operation, VAD was placed between the functional left atrium and ascending aorta, serving as a "artificial single ventricle" with neither pumping chamber nor artificial support in the right side of the heart. The systemic circulation was maintained by keeping relatively high central venous pressure. In another child (a 3-year-old) who underwent repair of incompetent atrioventricular valve leaving intracardiac lesions, VAD was placed between the common atrium and ascending aorta, serving as a pump for both pulmonary and systemic circulation with regulation of pulmonary blood flow through an aortopulmonary Gore-Tex shunt. The circulatory assist with VAD was utilized for 5 and 6 days, respectively. Although weaning from the device was not feasible in both patients because of the pulmonary dysfunction, these experience showed the possible use of VAD for cardiogenic shock after surgery in patients with complex cardiac anomalies.     

Contribution of Asian mouse subspecies Mus musculus molossinus to genomic constitution of strain C57BL/6J, as defined by BAC-end sequence-SNP analysis

MSM/Ms is an inbred strain derived from the Japanese wild mouse, Mus musculus molossinus. It is believed that subspecies molossinus has contributed substantially to the genome constitution of common laboratory strains of mice, although the majority of their genome is derived from the west European M. m. domesticus. Information on the molossinus genome is thus essential not only for genetic studies involving molossinus but also for characterization of common laboratory strains. Here, we report the construction of an arrayed bacterial artificial chromosome (BAC) library from male MSM/Ms genomic DNA, covering approximately 1x genome equivalent. Both ends of 176,256 BAC clone inserts were sequenced, and 62,988 BAC-end sequence (BES) pairs were mapped onto the C57BL/6J genome (NCBI mouse Build 30), covering 2,228,164 kbp or 89% of the total genome. Taking advantage of the BES map data, we established a computer-based clone screening system. Comparison of the MSM/Ms and C57BL/6J sequences revealed 489,200 candidate single nucleotide polymorphisms (SNPs) in 51,137,941 bp sequenced. The overall nucleotide substitution rate was as high as 0.0096. The distribution of SNPs along the C57BL/6J genome was not uniform: The majority of the genome showed a high SNP rate, and only 5.2% of the genome showed an extremely low SNP rate (percentage identity = 0.9997); these sequences are likely derived from the molossinus genome.     

Central command and the cutaneous vascular response to isometric exercise in heated humans

Cutaneous vascular conductance (CVC) decreases during isometric handgrip exercise in heat stressed individuals, and we hypothesized that central command is involved in this response. Seven subjects performed 2 min of isometric handgrip exercise (35% of maximal voluntary contraction) followed by postexercise ischaemia in normothermia and during heat stress (increase in internal temperature ∼1°C). To augment the contribution of central command independent of force generation, on a separate day the protocol was repeated following partial neuromuscular blockade (PNB; i.v. cisatracurium). Forearm skin blood flow was measured by laser-Doppler flowmetry, and CVC was the ratio of skin blood flow to mean arterial pressure. The PNB attenuated force production despite encouragement to attain the same workload. During the heat stress trials, isometric exercise decreased CVC by ∼12% for both conditions, but did not change CVC in either of the normothermic trials. During isometric exercise in the heat, the increase in mean arterial pressure (MAP) was greater during the control trial relative to the PNB trial (31.0 ± 9.8 versus 18.6 ± 6.4 mmHg, P < 0.01), while the elevation of heart rate tended to be lower (19.4 ± 10.4 versus 27.4 ± 8.1 b.p.m., P = 0.15). During postexercise ischaemia, CVC and MAP returned to pre-exercise levels in the PNB trial but remained reduced in the control trial. These findings suggest that central command, as well as muscle metabo-sensitive afferent stimulation, contributes to forearm cutaneous vascular responses in heat stressed humans.     

Rhythmical contractions in pulmonary arteries of monocrotaline-induced pulmonary hypertensive rats

Rhythmical contractions accompanied by an increase in cytosolic Ca2+ concentrations were produced in ring preparations of endothelium-denuded pulmonary arteries from monocrotaline-treated rats, but not in those from vehicle-treated rats, 2-3 h after a resting tension of 15 mN (150-180% of the initial wall length of the artery) was applied. The rhythmical contractions were abolished by nicardipine and ryanodine. Cyclopiazonic acid reduced the relaxation phase of the rhythmical contractions, finally leading to a sustained contraction. Similarly, apamin caused a sustained contraction, whereas charybdotoxin increased the amplitude of the rhythmical contractions. Glibenclamide had no apparent effects on them. Indomethacin and the prostaglandin H2/thromboxane A2 receptor antagonist SQ29548 abolished the rhythmical contractions and reduced the tension, but the thromboxane synthase inhibitor ozagrel had no effect. These results suggest that optimal stretch induces rhythmical contractions in the pulmonary arteries of monocrotaline-induced pulmonary hypertensive rats, to which both Ca2+ influx through voltage-operated Ca2+ channels and Ca2+ release from the endoplasmic reticulum seem to contribute. It is also suggested that small-conductance Ca(2+)-activated K+ channels participate in the relaxation phase of rhythmical contractions. Furthermore, prostaglandin H2 released from nonendothelial cells is likely to play a pivotal role in the induction of rhythmical contractions.