Hypokinesia of associated movement in Parkinson's disease: a symptom in early stages of the disease

We compared the degrees of impairment between intended voluntary movement and its simultaneous automatic associated movement in Parkinson's disease (PD). We studied wrist dorsiflexion as a movement associated with grip in 20 patients with PD and in 20 normal controls. The patients showed a significantly smaller dorsiflexion as compared with the controls. The decrease in associated movement was related to the severity of clinical stage of the disease, while gripping was performed well in each stage. The temporal relationship between grip and associated movement was the same for both groups of subjects. The patients showed no disturbance of amplitude or velocity for a single motor act of wrist dorsiflexion. Persons with PD have a greater reduction of automatic associated movement than intended voluntary movement. This may be one of the bases of clinical symptoms of PD patients in early stages of the disease.

Biochemical significance of 19-hydroxytestosterone in the process of aromatization in human corpus luteum

19-Hydroxyandrogens are known to be an intermediary metabolite in the aromatizing reaction, though the physiological role of this compound has not yet been clarified. In this study, microsomes obtained from human corpus luteum were incubated with testosterone or 19-hydroxytestosterone (19-OHT) as the substrate to investigate the biochemical significance of 19-OHT in the process of aromatization in the ovary. The inhibitory effects of 4-hydroxyandrostenedione (4-OHA) on the formation of estradiol from testosterone and 19-OHT in human ovary were also investigated. When testosterone was incubated with human ovarian microsomes, 19-OHT and estradiol were identified. When 19-OHT was used as the substrate, the formation of estradiol was demonstrated. To our knowledge, this is the first report to demonstrate the formation of estradiol from 19-OHT in human ovarian tissue. The Km value of aromatase for testosterone on human corpus luteum microsomes was 0.21 microM. 4-OHA exhibited inhibition with a Ki of 35 nM. With testosterone and 19-OHT as the substrate, the formation of estradiol was also equally inhibited by 4-OHA. A dose dependent inhibition of estradiol formation was observed, with no apparent accumulation of 19-OHT. These results suggest that 19-OHT may not only be an intermediary metabolite in the aromatization of testosterone by human ovary but could be a product of the microsomal enzyme.

Involvement of annexin I and annexin II in hepatocyte proliferation: can annexins I and II be markers for proliferative hepatocytes?

Annexin is the name of a new family of Ca(2+)-dependent membrane-binding proteins. Eleven types of its related proteins have been reported to date. Among those, annexin I and annexin II have been reported to possess many biological functions in vitro. Its actual role in vivo, however, is yet unknown. The involvement of annexin I and annexin II in the proliferation processes of hepatocytes was examined in the following aspects: (a) hepatocyte proliferation after carbon tetrachloride-induced liver damage, (b) hepatocyte regeneration after partial hepatectomy and (c) postnatal development of hepatocytes. These results showed collectively that annexin I and annexin II were increased in proliferative (or regenerative) hepatocytes, suggesting that both proteins play a certain role in the proliferation event. Furthermore, annexin I- and annexin II-positive hepatocytes always show a wider distribution than that of proliferating cell nuclear antigen or cytokeratin 7-positive hepatocytes, indicating that annexin I and annexin II may be useful markers for detecting not only actively proliferating hepatocytes but also hepatocytes in preproliferative and postproliferative stages.

[Prevention of coronary spasm during and shortly after coronary revascularization in patients with variant angina]

From June 1990 to March 1993, 9 patients undergoing coronary artery bypass grafting (CABG), 4.4% of all CABG cases at our hospital during this period, had significant perioperative coronary spasm. For 4 patients who underwent CABG before May 1992 (Group 1), preventive and suppressive procedures for the coronary spasm were the addition of diltiazem in the cardioplegic solution and the continuous intravenous infusion of nitroglycerin. Perioperative myocardial infarction (PMI) occurred in all 4 patients in Group 1, with the mean peak MB-CPK of 356 +/- 197 IU/l. One patient had delayed sternal closure because of his unstable hemodynamic status. Thereafter, we changed our protocol as follows: 1) Ergometrine loading (intracoronary infusion) test was performed in all candidates for CABG, aiming at finding out patients with a high risk. And for the high-risk patients, in addition to the measures done in Group 1, 2) intraaortic balloon pumping was performed through the perioperative period, and 3) a pig-tail catheter was dwelled in the Valsalva sinus, through which bolus doses of isosorbide dinitrate were injected frequently in this period. 4) Additionally nifedipine was periodically administered through the nasogastric tube. With these intensive preventive/suppressive measures, the perioperative spasm in 5 patients (Group 2) with variant angina were successfully managed, with no resultant PMI nor operative death (The occurrence of PMI was significantly less frequent in Group 2 than in Group 1, with the p value < 0.05). For patients with variant angina undergoing CABG, combined intensive preventive/suppressive measures for perioperative coronary spasm as listed above proved effective.

Determination of end-tidal sevoflurane concentration for tracheal intubation and minimum alveolar anesthetic concentration in adults

The purpose of this study was to determine both the concentration of sevoflurane required for tracheal intubation (MACEI) and its minimum alveolar anesthetic concentration (MAC) in adults. The study group consisted of 86 elective surgical patients, ASA physical status I or II, aged 16-59 yr. There was no premedication administered. For MACEI determination, after establishing and maintaining the predetermined end-tidal concentration for 20 min, tracheal intubation was attempted using a cuffed tracheal tube without muscle relaxant or other adjuvants. Each concentration at which tracheal intubation was attempted was predetermined as follows: 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, 5.0%, 5.5%, 6.0%, 6.5%, and 7.0%. For MAC determination, the patients examined were basically the same as those for MACEI determination, except for those who received muscle relaxant or other adjuvants because they were "not intubated smoothly." After establishing and maintaining the predetermined end-tidal concentration for 20 min, skin incision was attempted. Each concentration at which skin incision was attempted was predetermined as follows: 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, and 3.0%. The MACEI of sevoflurane was 4.52% (95% confidence limits, 3.91%-5.21%), and the ED95 for tracheal intubation was 8.07%. The MAC of sevoflurane was 1.58% (95% confidence limits, 1.14%-1.98%), and the AD95 (anesthetic ED95) was 2.96%. The MACEI/MAC ratio was 2.86 (95% confidence limits, 2.63-3.43). Anesthesia induction followed by tracheal intubation can be accomplished in adults when sevoflurane is administered as a sole anesthetic, but in excess of 8% end-tidal concentration.

Olfactory bulbectomy leads to learning/memory impairments in 3-panel runway and 3-lever operant tasks

The effects of olfactory bulbectomy on the learning and memory of rats were examined, using several memory tasks. In reference memory and working memory tasks using a 3-panel runway apparatus, acquisition was delayed markedly by bilateral ablation of the olfactory bulb (OB). OB lesion performed after acquisition markedly impaired both reference and working memories. Even when the tasks were repeated for several sessions, the impairment of memory in OB-lesioned rats did not recover to the control level of the sham operation group. The delayed matching-to-lever location (DMLL) performance, which was examined using a 3-lever operant apparatus, was markedly impaired by OB lesions. This impairment was mild immediately after surgery, but tended to increase with time. Rats with OB-olfactory tubercule lesions show more severe impairment of memory in the DMLL performance. Reversal learning, using a 2-lever operant apparatus, was markedly impaired by OB lesions. The impairment of working and reference memories in OB lesioned rats, which was assessed using a 3-panel-runway apparatus, was reduced by cholinesterase inhibitor physostigmine and NIK-247. These findings suggest that the OB plays a very important role in the learning and memory processes necessary for both a working memory task and a reference memory task and that, at least in part, the memory impairment in OB lesioned rats is mediated by lowering of cholinergic function.

Role of extracellular matrix in wound repair by cultured gastric mucosal cells

Effects of extracellular matrix on wound repair of cultured gastric epithelial cells were assessed. Artificial wounds were made by mechanical cell denudation in confluent rabbit gastric epithelial cell sheets which were formed on different types of extracellular matrix (e.g., collagen type I and type IV, laminin, fibronectin and Matrigel). Changes in wound size were analyzed quantitatively. Cell migration and proliferation were observed in stages of the wound repair process. The speed of wound repair was different with each extracellular matrix studied and was fastest on Matrigel. The type of extracellular matrix used in this study modulated both cell migration and proliferation. Therefore, it is concluded that extracellular matrix plays an important role in rates of gastric mucosal wound healing.

Blockade of hippocampal M1 muscarinic receptors impairs working memory performance of rats

In order to clarify the roles of hippocampal M1 and M2 muscarinic receptors in working and reference memory performance of rats, the effects of intrahippocampal injections of selective antagonists at both receptors on this behavior were examined with a three-panel runway task. In the working memory task, the M1 muscarinic receptor antagonist pirenzepine, injected bilaterally at 0.32 and 1.0 microgram/side into the dorsal hippocampus, significantly increased the number of errors (attempts to pass through two incorrect panels of the three panel-gates at four choice points). This effect of intrahippocampal pirenzepine (1.0 microgram/side) on working memory was attenuated by concurrent injection of 10 micrograms/side AF102B, the selective M1 muscarinic receptor agonist. Intrahippocampal injection of the M2 muscarinic receptor antagonist methoctramine at doses up to 1.0 microgram/side had no significant effect on the number of working memory errors. Intrahippocampal methoctramine injection at 3.2 micrograms/side produced a significant increase in working memory errors, an effect that was reversed by concurrent injection of 10 micrograms/side AF102B. Concurrent injection of 0.32 microgram/side methoctramine significantly reduced the increase in working memory errors induced by intrahippocampal pirenzepine (1.0 microgram/side). In the reference memory task, neither pirenzepine nor methoctramine affected the number of errors when injected into the hippocampus at doses up to 1.0 and 3.2 micrograms/side, respectively. These results suggest that processes mediated by M1 muscarinic receptors in the hippocampus are involved in working memory, but not in reference memory, and that blockade of hippocampal M2 muscarinic receptors ameliorates working memory deficits produced by M1 muscarinic blockade, possibly by increasing acetylcholine release.

Ocular torsion during microgravity on a space mission in 1992

On a space mission in 1992 we investigated the effect of pure neck receptor stimulation on eye roll position in space. To do this, we used the flash afterimage method. We found that eye rotations in static tilted head positions are absent in weightlessness. This suggests that in microgravity the neck position receptors do not contribute to a measurable extent to static OCR.

Failure to discriminate conspecifics in amygdaloid-lesioned mice

An experiment was conducted to investigate the role of the amygdala in the discriminative behavior of mice using the conditioned individual preference (CIP) method, a modified conditioned place preference (CPP) paradigm. CIP training of the subject mice involved 6 consecutive days of alternate IP injections of morphine (3 mg/kg) or saline followed by associations with a stimulus mouse in one compartment of the preference box. After the CIP training, the subject mice were given a choice between the morphine-associated and the saline-associated stimulus mice. Normal and sham-operated mice showed preference for the morphine-associated stimulus mouse. On the other hand, mice receiving bilateral amygdala lesions before or after CIP training did not show any preference for either stimulus mouse. These results support the view that the amygdala influences expression and acquisition of conditioned discriminant behaviors of mice by possibly interacting centrally, through its opiate receptors, with the peripherally injected morphine.

Telescience testbed experiments for biomedical studies: fertilization potential recording of amphibian eggs using tele-manipulation under stereoscopic vision

The telescience testbed experiments were carried out to test and investigate the tele-manipulation techniques in the intracellular potential recording of amphibian eggs. Implementation of telescience testbed was set up in the two separated laboratories of the Tsukuba Space center of NASDA, which were connected by tele-communication links. Manipulators respective for a microelectrode and a sample stage of microscope were moved by computers, of which command signals were transmitted from a computer in a remote control room. The computer in the control room was operated by an investigator (PI) who controlled the movement of each manipulator remotely. A stereoscopic vision of the microscope image were prepared by using a head mounted display (HMD) and were indispensable to the intracellular single cell recording. The fertilization potential of amphibian eggs was successfully obtained through the remote operating system.

[Investigation of AZT susceptibility of sequential HIV-1 isolates from patients treated with ddI after long-term therapy with AZT]

AZT susceptibility of sequential 12 HIV-1 isolates was investigated by culture method. These isolate were obtained from three patients who had received AZT for at least 12 months and switched to ddI after they appeared to deteriorate clinically. Cultures of isolate from a patient before therapy with AZT or ddI did not show cytopathic effect (CPE) in the presence of 0.1 microM or 1.0 microM AZT. Culture of 2 isolates from two patients treated with AZT more than 6 months before switched to ddI therapy showed CPE in the presence of AZT and HIV-1 p24 antigen was detected by ELISA in the supernatants. Culture of 6 of 7 isolates from three patients treated with ddI after long-term therapy with AZT also showed CPE in the presence of 1.0 microM AZT and HIV-1 p24 antigen was detected. These results demonstrated that AZT-resistant variant was still a dominant population in the isolate from patients after 11 to 13 months of discontinuing AZT therapy.

Regional oxygen consumption persists in dyskinetic canine myocardium

Regional myocardial O2 consumption was measured in anesthetized dogs both in baseline conditions and during intracoronary infusion of lidocaine, verapamil, sodium citrate, or 2,3-butanedione-monoxime (BDM). Despite regional hypokinesis and dyskinesis during drug infusion, regional O2 consumption was reduced only 30-40% by lidocaine, verapamil, and citrate and not at all by BDM. These results cast doubt on an important assumption of the "hibernation" theory: the protective matching of regional perfusion and contraction.

Elevated protein-tyrosine-phosphatase activity in human colon-carcinoma

We have examined the activity of protein tyrosine phosphatase in various tumor cell lines and surgically resected human colon carcinoma specimens. The protein tyrosine phosphatase activity of rat fibroblasts increases with the transformation by v-src gene. Likewise human colon carcinoma and human neuroblastoma cell lines, in which the activation of c-src tyrosine kinase was reported, show elevated protein tyrosine phosphatase activity in most cases. We compared the protein tyrosine phosphatase activity of eight human colon cancer tissues with that of normal mucosa of the same patient. The results show that the protein tyrosine phosphatase activity in tumor tissue was increased, suggesting the biological significance of protein tyrosine phosphatase in colon cancer.

Quantitation of the hydroxyl radical adducts of salicylic acid by micellar electrokinetic capillary chromatography: oxidizing species formed by a Fenton reaction

There has been controversy concerning the products formed by a Fenton reaction. We determined the hydroxyl radical (.OH) generated in a Fenton reaction system with no iron chelator using micellar electrokinetic capillary chromatography (MECC). The hydroxyl radical generated in this Fenton system attacked salicylic acid to produce major products of 2,3- and 2,5-dihydroxybenzoic acid (DHB), 2,3-DHB being prominent. Hydroxyl radical scavengers, such as mannitol, ethanol, thiourea and a ferric chelator, Desferal, significantly diminished the peaks for DHBs, showing production of .OH. We compared the MECC method with the electron paramagnetic resonance (EPR) spin trapping technique. The quantity of DHBs obtained by MECC increased dose-dependently up to 1 microM Fe2+ at a fixed concentration of H2O2, whereas that of the spin adduct by EPR showed a bell-shaped curve. This quantitation of .OH adducts by MECC supports the proposal that the oxidizing species formed by a Fenton reaction with no chelator is .OH. The EPR spin trapping method appears to be erroneous, particularly when iron is present at a higher concentration than hydrogen peroxide. The application of this method to the paraquat effect in vitro is demonstrated, and the possibility for analysis of .OH in vivo is also discussed.

Two distinct pathways are involved in the endothelin-3-evoked dopamine release from rat striatal slices

We investigated mechanisms mediating endothelin-3-evoked dopamine release from rat striatal slices. Endothelin-3 stimulated dopamine release from the slices in a concentration-dependent manner over a range from 1 to 10 microM. Tetrodotoxin suppressed dopamine release, but left 40% of the release unaffected. Nifedipine, a voltage-gated Ca2+ channel (VGCC) antagonist, significantly inhibited dopamine release in the presence and absence of tetrodotoxin. Endothelin-3-evoked dopamine release was attenuated by D-2-amino-5-phosphnovaleric acid or Mg2+, N-methyl-D-aspartate receptor inhibitors, and this attenuation was not observed in the presence of tetrodotoxin, thereby indicating that the tetrodotoxin-sensitive component of dopamine release was partially mediated by glutamatergic pathways. This view was also supported by findings that endothelin-3 evoked glutamate release and the exogenously applied glutamate stimulated dopamine release. Based on these results, we hypothesize that endothelin-3 produces dopamine release through two distinct mechanisms; one is a direct stimulation of dopaminergic nerve terminals and the other was activation of interneurons which promoted the release of glutamate, resulting in dopamine release.

Ground based eccentric chair experiments

Two subjects were rotated eccentrically in a manner described before. In contrast to a normal control group settings of a luminous line to the subjective vertical were almost unrelated to the gravitoinertial summation vector of gravity and centrifugal forces about four weeks before and totally so shortly after space flight. Only after four days post flight had passed a noticeable relation to the gravitoinertial vector re-established itself in the one subject which actually flew. The correspondence became normal six days after flight. Since there were no clinical abnormalities evident in the subjects, it is suggested, that both subjects suppressed their vestibular information presumably as an effect of vestibular deconditioning training before flight. In addition as a consequence of the flight experience one subject continued to ignore it several days after the flight.

Changes of ampulla pressure in the semicircular canal of pigeons by caloric stimulation

Still now several hypotheses about the mechanisms of the caloric nystagmus have been in conclusive. In this study we confirmed the convection effect and the volume change effect of the endolymph in horizontal semicircular canal following the caloric stimulation using pigeons (Columba livia). Although the direction of the caloric nystagmus depended on the head position and the stimulus site of calorization, the caloric nystagmus disappeared after plugging of horizontal semicircular canal. On the other hand, the ampulla pressure increased by cold calorization and decreased by hot calorization and these pressure changes had no relation to the head position. These results show that the main role of the mechanisms of the caloric nystagmus under 1G is the convection effect but the volume change effect may act on the caloric nystagmus not only under 1G but also under microgravity.