Evoked potentials and EEG in multiple sclerosis

Thirteen patients with clinically definite multiple sclerosis (MS) were studied with electroencephalogram (EEG), magnetic resonance imaging (MRI), evoked potentials and cerebrospinal fluid (CSF) analysis. We attempted to correlate the findings with physical disability as defined by Kurtzke score and presence of dementia or seizures. More severe plaque disease on MRI and increased physical disability correlated significantly with abnormality on brain-stem auditory evoked potentials (BAEPs) while visual evoked potential (VEP) abnormality correlated only with MRI findings. No such correlation was found with the EEG. The close relationship between BAEP and MRI abnormalities probably reflects frequent involvement of brain-stem corticospinal pathways.     

Metabolism of cysteine and cysteinesulfinate in rat and cat hepatocytes

The metabolism of cysteine and cysteinesulfinate was studied in freshly isolated hepatocytes from fed rats and cats. In incubations of rat hepatocytes with cysteinesulfinate, the rate of hypotaurine plus taurine production was approximately the same as the rate of conversion of the 1-carbon of cysteinesulfinate to CO2. In contrast, no significant production of hypotaurine plus taurine occurred in incubations of cat hepatocytes with cysteinesulfinate. These data are consistent with the species difference in the activity of hepatic cysteinesulfinate decarboxylase, which converts cysteinesulfinate to hypotaurine. In incubations of either rat or cat hepatocytes with cysteine, no hypotaurine plus taurine production was detected. However, the 1-carbon of cysteine was converted to CO2 and the production of urea plus ammonia nitrogen was significantly increased over the rates observed in incubations of cells without substrate. Our results suggest that most cysteine oxidation by hepatocytes occurs by pathways that do not involve formation of cysteinesulfinate.     

Umbilical polyp in infants and children.

AIM OF THE STUDY: The umbilical polyp is a rare congenital lesion resulting from the persistence of omphalomesenteric duct (OMD) enteric mucosa at the umbilicus. Exploration of the abdomen to exclude the presence of associated OMD remnants is controversial. The aim of this study was to evaluate the need for peritoneal cavity exploration in children with umbilical polyp. METHODS: All umbilical lesions (n = 53) excised between 1995 and 2005 in a single institution were reviewed to identify patients with umbilical polyp (n = 13). This is characterised histologically by the presence of gastrointestinal mucosa. A follow-up study of patients with umbilical polyp was performed. Data are reported as median (range). RESULTS AND CONCLUSIONS: All 13 patients underwent excision of an umbilical polyp at a median age of 15.1 months (3.1 - 80.5). All presented with a discharging polyp (associated with bleeding in 9) which did not respond to topical silver nitrate. Median diameter of the lesions was 0.5 cm (0.2 - 1). Histology revealed the presence of small bowel mucosa in 11 (associated with pancreatic tissue in 1 and gastric mucosa in 1) and large bowel mucosa in 2. All patients underwent inspection and probing of the base of the polyp after its excision. In 6 patients an associated OMD anomaly was suspected and exploration of the peritoneal cavity was performed (mini-laparotomy in 5 and laparoscopy in 1). No OMD anomaly was found. The 7 children who did not undergo exploration of the abdominal cavity remain asymptomatic after 5.8 years (0.9 - 13.7) follow-up. An umbilical polyp can be present in the absence of other OMD anomalies. Exploration of the peritoneal cavity in children with an umbilical polyp does not seem to be necessary.     

EEG and evoked potentials in episodic-dyscontrol syndrome.

The neurophysiologic correlates of explosive rage and violence are uncertain and controversial. We recorded 17-channel electroencephalograms (EEGs), brainstem auditory-evoked potentials (BAEPs), and long-latency auditory-event-related potentials (AEPs) in 23 patients with impulsive, aggressive and violent behavior satisfying criteria for episodic-dyscontrol syndrome. Most patients also satisfied criteria for intermittent explosive disorder, although some had had conduct disorders in childhood or had previously used psychoactive substances. Sixteen of 23 patients had normal EEGs, while 7 had diffuse or focal slowing not ascribable to drowsiness or the effects of medication. They differed significantly from 20 age-matched patients with headaches, of whom 1 had an abnormal EEG (chi 2 = 4.68, p < 0.05), and from 24 depressed patients, all of whose EEGs were normal (chi 2 = 4.83, p < 0.05). Patients and normal control subjects did not differ in BAEP latencies. N100 and P160 AEP amplitudes were lower in episodic-dyscontrol patients than in control, but the difference was not significant. These findings suggest that non-specific cerebral dysfunction and EEG changes may be associated with disordered impulse or behavior control. Episodic dyscontrol may be associated with other evidence of minimal brain dysfunction.     

Viral infections in the mouth

Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis.     

Neuropsychological and psychiatric correlates of intractable pseudoseizures.

Psychogenic seizures can mimic convulsive epilepsy and with repetitive attacks, iatrogenic complications from aggressive treatment of status epilepticus can occur. We studied neuropsychiatric features of 20 patients in whom psychogenic seizures were intractable and at times continuous. Nineteen of 20 patients seen were female, and all but one were under 40 years of age. All had convulsive attacks resistant to various medications, normal neurological examinations, and negative imaging studies and electroencephalograms (EEGs). Sixteen had previous evidence of epilepsy and the other four had epileptic relatives. Seizures were atypically prolonged, included back arching and pelvic thrusting, and persisted despite intravenous diazepam and therapeutic phenytoin and phenobarbital levels. Seizures terminated spontaneously in five, were stopped by suggestion in four, and persisted until respiratory arrest or elective intubation in 11. Ten patients had conversion disorder, six borderline or mixed personality disorder and four mental retardation. Fifteen had had some precipitating stressor and the remainder had histories of exhibiting attention-seeking behaviour. Nine of 10 patients with conversion disorder had 'conversion V' Minnesota Multiphasic Personality Inventory (MMPI) profiles, while personality disorder patients had elevation of several psychopathological scales. Patients with conversion disorder gradually improved with anticonvulsant discontinuation, while retarded individuals were helped by behaviour modification, situational change or neuroleptics. Personality disorder patients continued to have attacks and eventually discontinued follow-up. Clinical evidence of non-epileptic seizures includes clinical atypicality and long duration, exacerbation by medications and frequent attacks despite normal examination and studies.(ABSTRACT TRUNCATED AT 250 WORDS)