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51.
52.
Abstract: Monoamine and their acid metabolites were determined in the CSF of 18 drug-treated chronic schizophrenic patients with the symptoms of tardive dyskinesia and neuroleptic-induced Parkinsonism (Parkinsonism). Six healthy volunteers were used as the control group.
The norepinephrine (NE) levels were found to be significantly higher in the patients with tardive dyskinesia than in the controls. Furthermore, elevated CSF NE levels were also observed in the patients with Parkinsonism. Epinephrine (E) and Dopamine (DA) were not present in the CSF of the control group, whereas measurable levels of DA could be detected in 4 out of 9 and E was found in 8 out of 9 patients with tardive dyskinesia. The mean concentration of HVA was slightly but not significantly elevated in the patients with tardive dyskinesia and Parkinsonism. The mean values of CSF 5-HIAA were all within the normal range in both patient groups. From the above results, it was suggested that abnormal adrenergic activity rather than abnormal dopaminergic activity may play an important role as a mechanism in the etiopathogenesis of extrapyramidal disorders. Furthermore, in the patients with Parkinsonism, CSF neurochemical observations were similar to those of the patients with tardive dyskinesia in this study. It may help to explain the clinical coexistence of tardive dyskinesia and neuroleptic-induced Parkinsonism.  相似文献   
53.
1-N-(D-Threo-3-amino-2-hydroxybutanoyl)-2',3'-dideoxykanamycin+ ++ A has been prepared by coupling of 3,6'-bis(N-benzyloxycarbonyl)-2',3'-dideoxy-3"-N-(trifluoroacetyl)kanamy cin A with D-threo-3-azido-2-hydroxybutanoic acid. A diastereomeric mixture of the erythro analog has also been prepared by use of racemic erythro-3-azido-2-hydroxybutanoic acid. Synthesis of the D-threo- and racemic erythro-3-amino-2-hydroxybutanoic acids has been described.  相似文献   
54.
Three cases (case 1, female, aged 30; case 2, male, aged 32; case 3, male, aged 34) of benign brainstem encephalopathy with truncal ataxia were reported. Two patients had prodromal symptoms Neurological examination revealed truncal ataxia in all cases. As additional neurological signs, anisocoria, mydriasis, nystagmus, ptosis, transient opsoclonus, and facial palsy were seen. There was neither drowsiness nor myoclonus in the three cases. On laboratory examinations, cold agglutination test revealed significant elevation in two cases. The examination of cerebrospinal fluid showed a moderate rise of proteins in one case, but did not revealed pleocytosis in any of the cases. Magnetic resonance imaging of one patient revealed an area of high intensity in the left pontine tegmentum by T2-weighed imaging. The prognosis for all these cases was good, and the reappearance of neurological signs was not present until now. Our cases were different from brainstem encephalitis (Bickerstaff's encephalitis) because of an absence of disturbed consciousness and no pleocytosis in the cerebrospinal fluid. Our cases were also different from "myoclonus-opsoclonus syndrome" because of an absence of myoclonus. We discussed a possibility of a new clinical syndrome which we call "benign brainstem encephalopathy with truncal ataxia".  相似文献   
55.
Summary We describe two patients with sporadic amyotrophic lateral sclerosis (ALS), who had developed progressive external ophthalmoplegia of a predominantly supranuclear type while they survived on respirators, and displayed histopathological abnormalities both typical and atypical of ALS. Patient 1 was a 43-year-old man with ALS of 5-year duration, who had initially exhibited fulminant ALS, and remained on a respirator for 4 years. Patient 2 was a 51-year-old man with ALS of 13-year duration, who remained on a respirator for 8 years. Both patients died in a totally locked-in state. Autopsy of both patients revealed not only histopathological abnormalities consistent with ALS, but also multisystem degeneration which involved the pontine tegmentum, substantia nigra, Clarke's dorsal nuclei and spinocerebellar tracts. In addition, Patient 2 displayed intracyto-plasmic neuronal basophilic inclusion bodies which exhibited marked immunoreactivity to anti-ubiquitin antibodies. Our case reports indicate that the longer survival which is possible through the use of respirators may make one subgroup of ALS patients prone to develop atypical clinical and neuropathological features which are not observed during the natural cours of ALS.Supported by a Grant-in-Aid from the Research Committee of CNS Degenerative Diseases, the Ministry of Health and Welfare of Japan, and by a Grant from Nihon University School of Medicine, Tokyo  相似文献   
56.
Summary Effects of verapamil on the acetylcholine (ACh)-induced K+ current were examined in single atrial cells, using the tight-seal whole-cell clamp technique. The pipette solution contained guanosine-5-triphosphate (GTP) or guanosine-5-O-(3-thiotriphosphate) (GTP-S, a non-hydrolysable GTP analogue). In GTP-loaded cells, ACh induced a specific K+ current, which is known to be mediated by pertussis toxin-sensitive GTP-binding (G) proteins. Verapamil (0.1–100 M) depressed the ACh-induced K+ current in a concentration-dependent fashion. In GTP-S-loaded cells, the K+ current remained persistently after wash-out of ACh, probably due to irreversible activation of G proteins by GTP-S. Verapamil (0.1–100 M) also depressed the intracellular GTP-S-induced K+ current. However, the magnitude of verapamil-depression of the K+ current in GTP-S-loaded cells was significantly smaller than that in GTP-loaded cells at concentrations between 1 and 10 M of the drug. From these results, it is suggested that verapamil may block not only the function of muscarinic ACh receptors but also of G proteins and/or the K+ channel itself and thereby depress the ACh-induced K+ current in isolated atrial myocytes.Supported by grants from the Ministry of Education, Science and Culture of Japan and the Research Program on Ca Signal Control Send offprint requests to Y. Kurachi at the above address  相似文献   
57.
Dopamine (DA) neurons respond to sensory stimuli that predict reward. To understand how DA neurons acquire such ability, we trained monkeys on a one-direction-rewarded version of memory-guided saccade task (1DR) only when we recorded from single DA neurons. In 1DR, position-reward mapping was changed across blocks of trials. In the early stage of training of 1DR, DA neurons responded to reward delivery; in the later stages, they responded predominantly to the visual cue that predicted reward or no reward (reward predictor) differentially. We found that such a shift of activity from reward to reward predictor also occurred within a block of trials after position-reward mapping was altered. A main effect of long-term training was to accelerate the within-block reward-to-predictor shift of DA neuronal responses. The within-block shift appeared first in the intermediate stage, but was slow, and DA neurons often responded to the cue that indicated reward in the preceding block. In the advanced stage, the reward-to-predictor shift occurred quickly such that the DA neurons' responses to visual cues faithfully matched the current position-reward mapping. Changes in the DA neuronal responses co-varied with the reward-predictive differentiation of saccade latency both in short-term (within-block) and long-term adaptation. DA neurons' response to the fixation point also underwent long-term changes until it occurred predominantly in the first trial within a block. This might trigger a switch between the learned sets. These results suggest that midbrain DA neurons play an essential role in adapting oculomotor behavior to frequent switches in position-reward mapping.  相似文献   
58.
To ensure the effects of multipurpose solutions (MPS) for hydrogel contact lenses on the cornea, the inhibitory activity of three types of MPS on corneal cells has been evaluated with the use of scrape loading and dye transfer assay (SLDT assay) and Western blotting on rabbit corneal keratocytes (RC4). In SLDT assay, MPS-A and poloxamine showed dose-dependent inhibitory activity, suggesting the inhibitory action of MPS-A and poloxamine to gap junctional intercellular communication (GJIC) in the tested cells. Moreover, after treatment with MPS-A, the GJIC was initially inhibited within 4 h, and thereafter gradually turned to an approximately 60% level of the initial value. When MPS-A was removed from the incubation media after exposure of the cells, the recovery of GJIC was time dependent and returned to approximately initial levels at 8 h. Complete recovery was established after approximately 24 h. These findings suggested that the inhibitory action of MPS-A on corneal keratocytes was reversible. This inhibition was accompanied by a decrease in the quantity of connexin-43, which is a major protein constituting the gap junctional channel of these cells, and its change in the phosphorylation state. Taken together, it was suggested that MPS-A interacts with connexin-43, inducing an inhibitory action on GJIC.  相似文献   
59.
Summary The present study was designed to evaluate the effects of infrasound on behavioral performance in rats. The rats were divided into two groups, one selected for good performance (six rats: superior group) and the other for poor performance (six rats: inferior group) on the Rota-Rod Treadmill.Exposure conditions were as follows:Exp. 1 Control (150 min), Exp. 2 Exposure to infrasound with a main frequency of 16 Hz and a sound pressure level of 105 dB (S.P.L.) (70 min), Exp. 3 Exposure to infrasound with a main frequency of 16 Hz and a sound pressure level of 95 dB (S.P.L.) (70 min), Exp. 4 Exposure to infrasound with a main frequency of 16 Hz and a sound pressure level of 85 dB (S.P.L.) (150 min), Exp. 5 Exposure to infrasound with a main frequency of 16 Hz and a sound pressure level of 75 dB (S.P.L.) (150 min), Exp. 6 Exposure to Pink Noise of 72 dB (A) (70 min).Comparison of the pre-exposure endurance time (Maximum: 2 min) on the Rota-Rod Treadmill with endurance after exposure to infrasound showed that the endurance time of the superior group after exposure to 16 Hz, 105 dB was not reduced. The endurance of the inferior group was reduced by exposure to 16 Hz, 105 dB after 10 min, to 16 Hz, 95 dB after 70 min, and to 16 Hz, 85 dB after 150 min.  相似文献   
60.
BACKGROUND: Previous studies have suggested that early parental death may be associated with the emergence of bipolar disorder in later life. However, it remains unknown whether this association applies specifically to parental death due to suicide or only to early parental death. The present study aimed to explore whether suicide as well as the non-suicidal death of father, mother, or siblings are associated with an increased risk for bipolar disorder, and whether the possible association is modified by the age at which the subject experiences such a death in the family. METHODS: The subjects were born in 1960 or later and were first admitted to or had first contact with Danish psychiatric facilities between 1981 and 1998 with a diagnosis of bipolar disorder, and fifty age-matched controls per case were extracted. The effects of the deaths of relatives were estimated by means of a conditional logistic regression analysis. RESULTS: Among 947 subjects with bipolar disorder and 47,350 controls, those having experienced the parental suicide were significantly associated with an increased risk for BPD (incidence rate ratios: 1.83 [95% confidence interval: 1.07 to 3.12] for paternal suicide, 3.44 [1.97 to 6.00] for maternal suicide), whereas the non-suicidal death of parents showed no such association. Those having experienced maternal suicide at some point before reaching 10 years of age were seven times as likely to develop bipolar disorder. LIMITATIONS: The cohort members were followed until, but not exceeding, the age of 38. CONCLUSION: Early parental, particularly maternal, suicide increases the risk for bipolar disorder in the offspring. Possible explanations include a family history of mental disorders as well as psychosocial factors.  相似文献   
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