Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Circadian rhythms impact many physiological functions that may affect drug pharmacological response. Ketamine is a dissociative agent commonly used for surgical anesthesia in rats. The aim of the present study was to analyze the central nervous system (CNS) depression and lethality of ketamine injected intraperitoneally at different times during the 24 h. The study was conducted in October 2001, spring in the Southern hemisphere. Female prepuberal Sprague-Dawley rats synchronized to a 12h light: 12h dark cycle (light, 07:00h-19:00h) were studied. Ketamine (40 mg/kg) was administered to one of six different clock-time treatment groups (n = 6-7 rats each). Duration of latency period, ataxia, loss of righting reflex (LRR), post-LRR ataxia, and total pharmacological response were determined by visual assessment. To investigate acute toxicity, ketamine lethal dose 50 (148.0 mg/kg) was also administered as a single injection to six different treatment-time groups of rats. Significant temporal differences and circadian rhythms were detected in drug-induced post-LRR ataxia and total pharmacological response duration. The longest pharmacological response occurred in rats injected during the light (rest) phase and the shortest response in the dark (activity) phase. No circadian rhythm was detected in acute toxicity. The study findings indicate that the duration of CNS depression of ketamine in rats exhibits circadian rhythmic variation.
 ...
PMID:Treatment-time-dependent difference of ketamine pharmacological response and toxicity in rats. 1240 55

Two dogs developed alarming tremorgenic nervous stimulation shortly after ingesting discarded rice that had been forgotten in a refrigerator for an undetermined period and that was covered with a grey-green mould. Both dogs exhibited vomition followed by slight salivation, tremors and ataxia and 1 showed such severe agitation and seizures that it necessitated anaesthesia with thiopentone followed, on recovery, by xylazine. The other dog was only sedated with xylazine. They made an uneventful recovery. The rice vomitus yielded a pure culture of Penicillium crustosum. On chemical analysis it was negative for organochlorine, organophosphor and carbamate insecticides, as well as for strychnine, but contained 2.6 microg/g of the mycotoxins penitrem A as well as 34 microg/g of roquefortine as determined by LC-MS and confirmed by MS-MS. This is the 1st South African case of naturally occurring penitrem A toxicosis and also the 1st case where quantification of the levels of mycotoxins in dog vomitus is reported. The tremorgenicity of roquefortine and its contribution towards this syndrome, is questioned.
 ...
PMID:Tremorgenic neuromycotoxicosis in 2 dogs ascribed to the ingestion of penitrem A and possibly roquefortine in rice contaminated with Penicillium crustosum. 1266 36

Intraventricular aneurysms associated with fourth ventricular hemorrhage are rare. A case of a ruptured aneurysm in a choroidal branch of the right anterior inferior cerebellar artery (AICA) is reported here. A 56-year-old man presented with sudden onset of vertigo and nausea. CT scan showed an intraventricular hemorrhage within the fourth ventricle. Cerebellar angiography showed an aneurysm at the choroidal artery branching from the right AICA. The patient rejected both general anesthesia and craniotomy, so endovascular embolization under local anesthesia was performed using Guglielmi detachable coils (GDCs) and a fibered platinum coil. The distal portion of the right AICA and the aneurysm were obliterated. His postoperative course was fairly satisfactory. He suffered from a minimal gait disturbance caused by truncal ataxia for several days after the operation. He was discharged from hospital without neurological deficit. There have been only a few articles about choroidal artery aneurysms. As treatment, direct surgery has been recommended in past cases, but endovascular embolization of the parent artery was successfully performed in this case. Not only direct surgery but also endovascular surgery may be regarded as the treatments of choice for intraventricular aneurysms, depending on the size of the parent artery.
 ...
PMID:[A ruptured choroidal artery aneurysm of the anterior inferior cerebellar artery obliterated via the endovascular approach: case report]. 1275 25

Familial dysautonomia (FD) is a neurodevelopmental genetic disorder within the larger classification of hereditary sensory and autonomic neuropathies, each caused by a different genetic error. The FD gene has been identified as IKBKAP. Mutations result in tissue-specific expression of mutant IkappaB kinase-associated protein (IKAP). The genetic error probably affects development, as well as maintenance, of neurons because there is neuropathological and clinical progression. Pathological alterations consist of decreased unmyelinated and small-fiber neurons. Clinical features reflect widespread involvement of sensory and autonomic neurons. Sensory loss includes impaired pain and temperature appreciation. Autonomic features include dysphagia, vomiting crises, blood pressure lability, and sudomotor dysfunction. Central dysfunction includes emotional lability and ataxia. With supportive treatment, prognosis has improved greatly. About 40% of patients are over age 20 years. The cause of death is usually pulmonary failure, unexplained sudden deaths, or renal failure. With the discovery of the genetic defect, definitive treatments are anticipated.
 ...
PMID:Familial dysautonomia. 1498 33

Two groups of six mares aged from eight to 18 years were anaesthetised by caudal epidural injections of ropivacaine (0.5 per cent, 0.1 mg/kg) or a combination of ripovacaine (0.08 mg/kg) and fentanyl (100 microg) in a randomised study. The onset of anaesthesia was significantly more rapid (P<0.001) and it lasted significantly longer (P<0.001) in the group anaesthetised with the combination of drugs. The surgical comfort scores of the group anaesthetised with the combination were higher than those of the group anaesthetised with ropivacaine alone (P<0.001), and the quality of intraoperative analgesia, as assessed by the surgeon, was significantly improved. There were no differences between the groups in their average scores for the levels of ataxia and sedation, in their behaviour, or in the incidence of side effects.
 ...
PMID:Comparison of ropivacaine with a combination of ropivacaine and fentanyl for the caudal epidural anaesthesia of mares. 1506 41

Eleven cats with signs of cerebellar dysfunction, developed on recovery from a brief and uneventful general anesthesia, were examined at the Koret School of Veterinary Medicine Teaching Hospital (KSVMTH) between 1998 and 2002. Neurological signs included mild to severe ataxia of all 4 limbs, intentional tremor, lack of menace response, and delayed hopping. The cats were of different ages when anesthetized and none had shown any prior signs of neural disease. They were examined 1 day to 4 years after onset of clinical signs, and the neurological deficits remained unchanged in a follow-up period of 6 months to 8 years. Medical and anesthetic records showed that all were Persian cross cats, 7 of them originating in the same city in Israel. Ketamine was the only anesthetic drug that had been used with all cats. It might be that a genetic component predisposes Persian cross cats to nonreversible cerebellar damage after exposure to an anesthetic dose of ketamine.
 ...
PMID:Postanesthetic cerebellar dysfunction in cats. 1518 28

The Chiari malformations are characterized by herniation of posterior fossa contents through the foramen magnum. Chiari I malformation is currently defined as ectopia of the cerebellar tonsils more than 5 mm below the foramen magnum. Extension of the cerebellar tonsils up to 3 mm may be found in the normal population. Although Chiari malformations are congenital, symptoms often do not manifest until the third and fourth decades of life, or even later. Patients usually present with headache, lower cranial nerve palsies, downbeat nystagmus, ataxia, or dissociated anesthesia of the trunk and extremities. Definitive diagnosis is made by magnetic resonance imaging (MRI), which shows the compressed tonsils extending through the foramen magnum into the cervical subarachnoid space. One of the rare presenting signs of Chiari I malformations is acquired esotropia with a divergence insufficiency pattern. We report such a case in which the initial neuroimaging showed tonsillar herniation, but of insufficient magnitude to meet diagnostic criteria for Chiari I malformation. When the strabismus recurred after initially successful eye muscle surgery, follow-up scan showed progressive tonsillar herniation.
 ...
PMID:Progressive cerebellar tonsillar herniation with recurrent divergence insufficiency esotropia. 1522 35

The purpose of the present study was to determine the most effective time interval between the administration of sufentanil long acting (LA) and the induction of sevoflurane anaesthesia in dogs. The occurrence of sedation, analgesia and other marked side-effects were evaluated in addition to the possible dosage-reducing effect of sufentanil on sevoflurane in dogs. Forty clinically normal beagles aged 1-2 years and weighing between 8.4 and 13.6 kg were included. Two control groups were used: one group of dogs (A) received sufentanil LA (50 microg/kg i.m.) and a second group (B) the sufentanil vehicle followed by standard inhalation anaesthesia of 90 min. After premedication with sufentanil LA immediately before (C0), 15 min (D15) or 30 min (E30) prior to induction with thiopental (i.v.) the dogs were anaesthetized for 90 min with sevoflurane in oxygen. Pain and sedation scores were evaluated every 10 min during sevoflurane anaesthesia and at 2 (T120), 4 (T240) and 24 h (T1440) after initiation of anaesthesia. The occurrence of adverse reactions such as hypothermia, lateral recumbency, ataxia, noise sensitivity, vomiting, defaecation, salivation, nystagmus and excitation was observed at the same time-points. During the recovery period pain scores were lower and sedation scores higher in the sufentanil LA groups. In many dogs acceptable pain and sedation scores persisted during 24 h. Several dogs showed ataxia, lateral recumbency, arousal on auditory stimulation, defaecation, salivation and excitation at several time-points after sufentanil LA administration. Sufentanil LA in addition to sevoflurane anaesthesia offered beneficial dosage-reducing analgesic effects up to 69.8% for thiopental and 78.3% for sevoflurane; although several typical opioid side-effects occurred. To achieve this advantageous dosage-reducing effect 15 min should be respected between sufentanil LA administration and induction of sevoflurane anaesthesia.
 ...
PMID:Anti-nociceptive and sedative effects of sufentanil long acting during and after sevoflurane anaesthesia in dogs. 1531 4

Ketamine is commonly administered in combination with benzodiazepines to achieve surgical anaesthesia in rats. The aim of the present study was to analyze the pharmacological response of the combination ketamine-midazolam injected intraperitoneally at different times of day to rats. The study was conducted in July 2003, during the winter in the Southern hemisphere. Female prepuberal Sprague-Dawley rats synchronized to a 12h light:12h dark cycle (light, 07:00-19:00h) were used as experimental animals. A combination treatment of ketamine (40 mg/kg) and midazolam (2 mg/kg) was administered to five different clock-time groups of rats (n=7/group). Duration of the latency period, ataxia, loss-of-righting reflex (LRR), post-LRR ataxia, and total pharmacological response were assessed by visual assessment. Significant treatment-time differences were detected in the duration of LRR, post-LRR ataxia, and total pharmacological response duration. The longest pharmacological response occurred in rats injected during the light (rest) phase, and the shortest pharmacological response occurred in rats injected during the dark (activity) phase. Cosinor analysis documented circadian rhythmicity in the duration of post-LRR ataxia. The findings of the study indicate the duration of CNS-depression of the ketamine-midazolam combination exhibits treatment-time-dependent variation in the rat.
 ...
PMID:Chronobiological study of the pharmacological response of rats to combination ketamine-midazolam. 1547 Sep 56

Despite major advances in skull base surgery and microsurgical techniques, surgery for vestibular schwannoma (VS) carries a risk of complications. Some are inherent to general anesthesia and surgery of any type and include myocardial infarction, pneumonia, pulmonary embolism, and infection. Some are specific to neurosurgery in this area of the brain, and include hydrocephalus, cerebrospinal fluid leak, facial nerve paralysis, facial numbness, hearing loss, ataxia, dysphagia, and major stroke. Even in the hands of very experienced acoustic surgeons, these risks cannot be eliminated. Radiosurgery provides an outpatient, noninvasive alternative for the treatment of small acoustic schwannomas. Initially radiosurgery was undertaken in "high-risk" patients, including the elderly, those with severe medical comorbidities, and those in whom tumors recurred after surgery. Additionally, a high rate of cranial nerve morbidity was reported. With improvements in dosimetry planning and dose selection, however, authors practicing at radiosurgical centers now report very low complication rates, as well as high tumor control rates. In this report the authors specifically review the results of linear accelerator-based radiosurgery for VS and compare these outcomes with the best surgical alternatives.
 ...
PMID:Linear accelerator-based radiosurgery for vestibular schwannoma. 1566 13


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