Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Complexins are presynaptic proteins that bind to the SNARE complex where they modulate neurotransmitter release. A number of studies report changes in complexins in psychiatric (schizophrenia and depression) and neurodegenerative disorders (Huntington's disease, Wernicke's encephalopathy and Parkinson's disease). Here, we characterize the behavioural phenotype of Cplx1 knockout (Cplx1-/-) mice. Cplx1-/- mice develop a strong ataxia in the absence of cerebellar degeneration. Although originally reported to die within 2-4 months after birth, when reared using an enhanced feeding regime, these mice survive normally (i.e. >2 years). Cplx1-/- mice show pronounced deficits in motor coordination and locomotion including abnormal gait, inability to run or swim, impaired rotarod performance, reduced neuromuscular strength, dystonia and resting tremor. Although the abnormal motor phenotype dominates their overt symptoms, Cplx1-/- mice also show other behavioural deficits, particularly in complex behaviours. They have deficits in grooming and rearing behaviour and show reduced exploration in several different paradigms. They also show deficits in tasks reflecting emotional reactivity. They fail to habituate to confinement and show a 'panic' response when exposed to water. The abnormalities seen in the behaviour of Cplx1-/- mice reflect those predicted from the distribution of complexin I in the brain. Our data show that complexin I is essential not only for normal motor function in mice, but also for normal performance of other complex behaviours. These results support the idea that altered expression of complexins in disease states may contribute to the symptomatology of disorders in which they are dysregulated.
 ...
PMID:Profound ataxia in complexin I knockout mice masks a complex phenotype that includes exploratory and habituation deficits. 1600 Mar 19

A 52-year-old patient with treatment-resistant paranoid schizophrenia developed severe parkinsonian features after more than 20 years of antipsychotic drug therapy. The role of this therapy was thought to have been a contributing factor to the patient's clinical presentation, although Parkinson's disease could not be ruled out. Originally, parkinsonian symptoms developed acutely and progressed to hand tremor, sialorrhea, upper body rigidity, masked facies, striatal hand, bradykinesia, and a severe, unsteady, shuffling gait. Tremor and rigidity were the only parkinsonian symptoms that responded to anticholinergic therapy. After converting from a first- to a second-generation antipsychotic drug, the patient maintained psychiatric stability, with some improvement in motor functioning-most notably decreased upper body rigidity. Our findings are consistent with the literature on quetiapine therapy in patients with Parkinson's disease in terms of adequately controlling psychosis without worsening motor symptoms. The difference, however, was that in most cases reported, psychotic features were the result of dopamine-enhancing treatments and not schizophrenia.
 ...
PMID:Quetiapine use in a patient with chronic schizophrenia and severe parkinsonism. 1623 27

Several factors suggest that spontaneous dyskinesia may be a useful supplemental phenotype for further elucidating the specific nature of the genetic contribution to schizophrenia. For example, involuntary movement abnormalities have been observed in both medicated and unmedicated schizophrenia patients, in individuals with schizotypal personality disorder, and sometimes in siblings of schizophrenia patients. However, there are many inconsistencies present in the literature to date. The current study thus sought to investigate the existence of spontaneous dyskinesia in schizophrenia patient probands, their non-psychotic siblings, and healthy controls in order to clarify its potential value as an "endophenotype" in genetic studies of schizophrenia. Videotaped interviews were coded for the presence of spontaneous, involuntary movement abnormalities by a trained and reliable rater using computer assisted technology who was blind to group and family status. The results of this study indicated that siblings of schizophrenia patients did not display significantly more involuntary movements compared to controls, although tremor was observed in a few siblings. In contrast, schizophrenia patients did display significantly more involuntary movements compared to controls as well as their non-psychotic siblings. The lack of significant differences between siblings and controls argues against a strong association between spontaneous dyskinesia and an "unexpressed" genetic liability to schizophrenia. Thus, it appears that involuntary movement abnormalities may be limited in their utility as endophenotypes in genetic studies of schizophrenia, despite being associated with, and perhaps predictive of, schizophrenia itself.
 ...
PMID:Spontaneous dyskinesia and familial liability to schizophrenia. 1630 68

We experienced perioperative management of a patient with schizophrenia who had been taking a large amount of antipsychotic agents until the cesarean section. A 31-year-old woman in 38th week gestation with schizophrenia underwent a cesarean section. Anesthesia was maintained with light plane of general anesthesia combined with epidural anesthesia. Perioperatively, the mother experienced no complications and the baby only developed slight generalized tremor and hypotonus for a short period after delivery.
 ...
PMID:[Anesthetic management of a cesarean section in a patient with schizophrenia receiving a large amount of antipsychotic agents]. 1637 Mar 38

Antiepileptic drugs (AEDs) affect various neurotransmitters (i.e. GABA, glutamate), receptors (i.e. GABAergic, glutamatergic), and ion channels (i.e. for sodium or calcium) which is responsible for their anticonvulsant activity. However, this broad spectrum of action may be also utilized in other pathological conditions. For example, both conventional and newer AEDs may be used in patients suffering from neuropathic pain, migraine, essential tremor, spasticity, restless legs syndrome and a number of psychiatric disorders (f.e. bipolar disease or schizophrenia). Also, isolated data point to their potential use in Parkinson's or Alzheimer's disease. There is experimental background indicating a potent neuroprotective efficacy of AEDs in numerous models of brain ischemia. However, the clinical data are very limited and this problem requires careful assessment.
 ...
PMID:Non-epilepsy uses of antiepilepsy drugs. 1653 24

The quaking viable mouse mutation (qk(v)) is a deletion including the 5' regulatory region of the quaking gene (Qki), which causes body tremor and severe dysmyelination in mouse. The function of the human quaking gene, called quaking homolog KH domain RNA-binding (mouse) (QKI), is not well known. We have previously shown that QKI is a new candidate gene for schizophrenia. Here we show that human QKI mRNA levels can account for a high proportion (47%) of normal interindividual mRNA expression variation (and covariation) of six oligodendrocyte-related genes (PLP1, MAG, MBP, TF, SOX10, and CDKN1B) in 55 human brain autopsy samples from individuals without psychiatric diagnoses. In addition, the tightly coexpressed myelin-related genes (PLP1, MAG, and TF) have decreased mRNA levels in 55 schizophrenic patients, as compared with 55 control individuals, and most of this difference (68-96%) can be explained by variation in the relative mRNA levels of QKI-7kb, the same QKI splice variant previously shown to be down-regulated in patients with schizophrenia. Taken together, our results suggest that QKI levels may regulate oligodendrocyte differentiation and maturation in human brain, in a similar way as in mouse. Moreover, we hypothesize that previously observed decreased activity of myelin-related genes in schizophrenia might be caused by disturbed QKI splicing.
 ...
PMID:Human QKI, a potential regulator of mRNA expression of human oligodendrocyte-related genes involved in schizophrenia. 1664 Oct 98

The accurate and objective measurement of abnormal, involuntary movements remains highly desirable, whether the movements are secondary to pharmacotherapy or an expression of the primary illness. In a previous study, we found that the prevalence of tardive dyskinesia in a sample of 100 subjects ranged from 28% when using the Abnormal Involuntary Movement Scale (AIMS) or the Dyskinesia Identification Scale, Condensed User Version (DISCUS) to 62% using an instrumental measurement (IM) of peripheral dyskinesia. The goal of this study was to examine the relationship between various risk factors for tardive dyskinesia as predictor variables, and the AIMS, DISCUS, and IMs of dyskinesia, tremor, and velocity of motor movement as dependent variables. The sample consisted of 100, mostly patients with schizophrenia. Poor performance on the Mini-Mental State Examination (MMSE) and increasing age were the most consistent predictors of dyskinetic and parkinsonian movements. Various predictors were associated with specific abnormal movements. Head injury was related to slower speed of motor movements and the total DISCUS score. A history of smoking was associated with less IM dyskinesia. For those with coexisting parkinsonism and dyskinesia, significant associations were found with head injury, diabetes mellitus, and an AIMS score of 2 or greater in 2 body areas. Various classes of psychotropic agents seemed to have little influence on the MMSE or the development of dyskinesia and parkinsonism. Increasing age and a lower score on the MMSE seem to be particularly helpful in gauging the risk for parkinsonian and dyskinetic movements.
 ...
PMID:Predictors of neuroleptic-induced dyskinesia and parkinsonism: the influence of measurement methods and definitions. 1711 Aug 11

The aim of the current study was to assess the prevalence of tardive movement disorders (TMD) among a group of institutionalized schizophrenic and schizoaffective patients in southern region of Israel. Chronic schizophrenic and schizoaffective inpatients of a psychiatric hospital and its affiliated hostels were screened for the presence of TMD subsyndromes. Twenty percent (107 patients) of 523 patients with schizophrenia and schizoaffective disorder exhibited TMD. Of those with TMD, 36% had only one subsyndrome, whereas 64% had a combination of several TMD subsyndromes. With regard to patients with TMD, the most frequent TMD subsyndrome was tardive tremor (TT). TT appeared more often in males compared to females and at a younger age (44.3+/-8 vs. 54.3+/-11 years, P<0.04). TD appearing in combination with other TMD subsyndromes was significantly more prevalent among females than in males (57% vs. 35%; P<0.02). TMD generally appears in a combined fashion. Further prospective studies from different geographical areas are recommended.
 ...
PMID:The prevalence of neuroleptic drug-induced tardive movement subsyndromes among schizophrenic and schizoaffective patients residing in the southern region of Israel. 1766 7

Antiepileptic drugs (AEDs) are used extensively to treat multiple non-epilepsy disorders, both in neurology and psychiatry. This article provides a review of the clinical efficacy of AEDs in non-epilepsy disorders based on recently published preclinical and clinical studies, and attempts to relate this efficacy to the mechanism of action of AEDs and pathophysiological processes associated with the disorders. Some newer indications for AEDs have been established, while others are under investigation. The disorders where AEDs have been demonstrated to be of clinical importance include neurological disorders, such as essential tremor, neuropathic pain and migraine, and psychiatric disorders, including anxiety, schizophrenia and bipolar disorder. Many of the AEDs have various targets of action in the synapse and have several proposed relevant mechanisms of action in epilepsy and in other disorders. Pathophysiological processes disturb neuronal excitability by modulating ion channels, receptors and intracellular signalling pathways, and these are targets for the pharmacological action of various AEDs. Attention is focused on the glutamatergic and GABAergic synapses. In psychiatric conditions such as schizophrenia and bipolar disorder, AEDs such as valproate, carbamazepine and lamotrigine appear to have clear roles based on their effect on intracellular pathways. On the other hand, some AEDs, e.g. topiramate, have efficacy for nonpsychiatric disorders including migraine, possibly by enhancing GABAergic and reducing glutamatergic neurotransmission. AEDs that seem to enhance GABAergic neurotransmission, e.g. tiagabine, valproate, gabapentin and possibly levetiracetam, may have a role in treating neurological disorders such as essential tremor, or anxiety disorders. AEDs with effects on voltage-gated sodium or calcium channels may be advantageous in treating neuropathic pain, e.g. gabapentin, pregabalin, carbamazepine, oxcarbazepine, lamotrigine and valproate. Co-morbid conditions associated with epilepsy, such as mood disorders and migraine, may often respond to treatment with AEDs. Other possible disorders where AEDs may be of clinical importance include cancer, HIV infection, drug and alcohol abuse, and also in neuroprotection. A future challenge is to evaluate the second-generation AEDs in non-epilepsy disorders and to design clinical trials to study their effects in such disorders in paediatric patients. Differentiation between the main mechanisms of action of the AEDs needs more consideration in drug selection for tailored treatment of the various non-epilepsy disorders.
 ...
PMID:Antiepileptic drugs in non-epilepsy disorders: relations between mechanisms of action and clinical efficacy. 1807 13

This research compared the long-term efficacy and safety of iloperidone with those of haloperidol in individuals with schizophrenia. Data were pooled from 3 prospective multicenter studies, each with 6-week stabilization followed by 46-week double-blind maintenance phases. Patients were randomized to iloperidone 4 to 16 mg/d or haloperidol 5 to 20 mg/d. Patients included in this analysis completed the initial 6-week phase with at least 20% reduction in Positive and Negative Syndrome Scale (PANSS) total score at weeks 4 and 6, had 7-item Clinical Global Impressions of Change (CGI-C) scores less than 4, received 1 or more doses of long-term phase medication, and had 1 or more efficacy/safety assessments during the long-term phase. The primary efficacy variable was time to relapse, defined as a 25% or more increase in PANSS total score, including at least a 10-point change; discontinuation because of lack of efficacy; aggravated psychosis with hospitalization; or 2-point increase in the 7-item CGI-C after week 6. Of 1644 patients randomized and 1326 completing the 6-week phase, 473 (iloperidone, n = 359; haloperidol, n = 114) were included in the long-term efficacy analysis, and 489 (iloperidone, n = 371; haloperidol, n = 118) in the safety analysis. Iloperidone was equivalent to haloperidol in time to relapse. The most common adverse events were insomnia (18.1%), anxiety (10.8%), and schizophrenia aggravated (8.9%) with iloperidone, and insomnia (16.9%), akathisia (14.4%), tremor (12.7%), and muscle rigidity (12.7%) with haloperidol. The Extrapyramidal Symptoms Rating Scale scores improved with iloperidone and worsened with haloperidol. Metabolic changes were minimal for both groups. Mean changes in Fridericia's QT interval correction were 10.3 msec (iloperidone) and 9.4 msec (haloperidol) at end point. Iloperidone demonstrated long-term efficacy equivalent to haloperidol and a favorable long-term safety profile, potentially making this agent a suitable option as maintenance therapy for schizophrenia.
 ...
PMID:Long-term efficacy and safety of iloperidone: results from 3 clinical trials for the treatment of schizophrenia. 1833 10


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>