The changes in EEG, evoked potentials and neurological recovery after global brain ischemia in dogs

Electroencephalography (EEG), evoked potentials and neurological recovery score were compared between 10 min and 15 min transient global brain ischemia in 18 dogs. The transient global brain ischemia was induced by occluding aorta, superior and inferior caval veins. The grade of EEG (1: normal approximately 5: flat) 2 hrs after ischemia was significantly lower with the 10 min ischemic group (n = 9) than with the 15 min group (n = 9) (3.7 +/- 0.5 vs 4.1 +/- 0.3, P less than 0.05). The rate of reappearance in evoked potential waves 2 hrs after ischemia was higher with the 10 min ischemic group than with the 15 min group (auditory brainstem response 5 wave: 100% vs 33%, middle latency response Pa wave: 80% vs 0%, somatosensory evoked potential N2 wave: 83% vs 78%, N3 wave: 67% vs 33%). The neurological recovery score (0: death approximately 100: normal) 7 days after ischemia was significantly higher with the 10 min group than with the 15 min group (58 +/- 34 vs 27 +/- 23, P less than 0.05). In both groups, there was a significant correlation (r = +0.85, P less than 0.01) between the total score of EEG and evoked potential waves (0: no wave appeared approximately 6: all waves appeared) 2 hours after ischemia and the neurological recovery score 7 days after ischemia. These results suggest that the neurological recovery after transient global brain ischemia would be estimated by EEG and evoked potential waves.     

Leukemia Cutis in Three Children: Clinical and Immunohistochemical Studies

Abstract: We report 3 children with leukemia cutis observed at the initial diagnosis of systemic leukemia. Leukemia subtypes in the three children were congenital monocytic, acute undifferentiated, and acute monocytic, respectively. The patients were girls age 10 days, 14 years, and 11 months, respectively, at diagnosis. We describe the clinical features of the cases and the results of immunohistochemical studies on paraffin-embedded skin biopsy specimens. The skin lesions were tumors and areas of reddish purple erythema in the first child, pigmented erythema in the second, and bright red erythema in the third. In the first two patients skin lesion biopsy specimens had dense leukemic infiltrates in the dermis with reactive T lymphocytes scattered among them. In the third patient, the infiltrating cells were almost all reactive T lymphocytes, with a few leukemic cells. A relationship between the leukemic-reactive cell ratio and the prognosis was suggested; dense leukemic cell infiltrates may be associated with a poor prognosis.     

Furosemide Given by Inhalation Ameliorates Acute Exacerbation of Asthma

Previous studies have suggested that inhaled furosemide may have a protective effect against a wide variety of bronchoconstrictor agents, but a therapeutic effect has not been established in acute exacerbation of asthma. The purpose of this study was to investigate whether inhaled furosemide would exhibit any therapeutic benefit in acute asthma. We conducted a double-blind, placebo-controlled, randomized study in 40 patients with acute mild or moderate exacerbation of asthma. All patients received intravenous (IV) aminophylline 250 mg for 90 min and IV hydrocortisone 100 mg at entry. After randomization, 3 patients were excluded from the final analysis. At 30 min after starting IV aminophylline, 20 patients were given inhaled furosemide 20 mg and 17 patients received normal saline as placebo-control. Both inhalations were given by a jet nebulizer. The baseline forced expiratory volume at 1 sec (FEV₁), peak expiratory flow rate (PEFR), and serum concentration of theophylline did not differ between the two groups. An increase in FEV₁ in the furosemide group by 28.2 ± 5.9% (mean ± SE) was noted at 60 min, and this was significantly higher than in the control group. PEFR at 60 min was also significantly higher in the furosemide group than in control group. We conclude that inhaled furosemide has a bronchodilator effect on mild to moderate exacerbation of asthma when it is used with IV theophylline. Inhaled furosemide may benefit certain acute asthma patients, especially those suffering complications from the adverse effects of β₂-agonists.     

Epidemiological studies of air pollution and health effects in areas near roadways with heavy traffic in Tokyo]

Recent concern regarding health effects of air pollution in Japan has concentrated mainly on traffic-induced air pollution and its health effects in large cities. In Japan, where many people in large cities have been living near major roadways, the increase of automobile exhaust due to heavy traffic congestion will predictably cause a greater impact on people living near major roadways. We surveyed the characterization of residential suspended particulate matter (SPM) and nitrogen dioxide (NO2) concentrations along the major roadways in Tokyo, along with a health survey on the respiratory conditions of residents living in the same area, to examine the relationships between indoor pollutant levels, prevalence of respiratory symptoms and distance from roadways. The environmental monitoring was conducted in five phases. Using a newly developed SPM sampler and NO2 filter badge, continuous 4 day (96 hours) measurements were conducted in two hundred residential homes for four weeks. NO2 was measured in the living room, kitchen and outside of each home, while SPM was monitored in the living room. Health information was collected in October 1987 using ATS-DLD self-administered questionnaires. Of the 1,093 homes investigated, responses from 805 homes were received. The following results were obtained. SPM and NO2 concentrations showed large variations. Indoor pollution levels mostly depended on indoor sources, i.e. cigarette smoking and unventilated space heaters, and the effects of those indoor sources were influenced by the building structure with respect to air tightness. An association between increase in pollutant levels and the distance from the roadway was observed. However its effect is small compared to indoor source effects. The prevalence rate of respiratory symptoms was higher in those areas nearest roadways with heavy traffic both in children and adults. These results suggest the presence of a relationship between automobile exhaust and health effects.     

Lidocaine Increases Intracellular Sodium Concentration through Voltage-dependent Sodium Channels in an Identified Lymnaea Neuron

Background: The local anesthetic lidocaine affects neuronal excitability in the central nervous system; however, the mechanisms of such action remain unclear. The intracellular sodium concentration ([Na+]i) and sodium currents (INa) are related to membrane potential and excitability. Using an identifiable respiratory pacemaker neuron from Lymnaea stagnalis, the authors sought to determine whether lidocaine changes [Na+]i and membrane potential and whether INa is related to these changes.

Methods: Intracellular recording and sodium imaging were used simultaneously to measure membrane potentials and [Na+]i, respectively. Measurements for [Na+]i were made in normal, high-Na+, and Na+-free salines, with membrane hyperpolarization, and with tetrodotoxin pretreatment trials. Furthermore, changes of INa were measured by whole cell patch clamp configuration.

Results: Lidocaine increased [Na+]i in a dose-dependent manner concurrent with a depolarization of the membrane potential. In the presence of high-Na+ saline, [Na+]i increased and the membrane potential was depolarized; the addition of lidocaine further increased [Na+]i, and the membrane potential was further depolarized. In Na+-free saline or in the presence of tetrodotoxin, lidocaine did not change [Na+]i. Similarly, hyperpolarization of the membrane by current injections also prevented the lidocaine-induced increase of [Na+]i. In the patch clamp configuration, membrane depolarization by lidocaine led to an inward sodium influx. A persistent reduction in membrane potential, resulting from lidocaine, brings the cell within the window current of INa where sodium channel activation occurs.     

Hyperthyroidism associated with papilloedema and pyramidal tract involvement

Summary In a patient with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes [MELAS] who had normal mitochondrial enzyme activity, high doses of coenzyme Q₁₀ (CoQ) were administered. Clinical improvement with decreased serum lactate and pyruvate levels was observed. Though the mechanism of action of CoQ is not known, a trial is worthwhile in patients with MELAS.     

Epilepsy syndromes associated with hypothalamic hamartomas.

PURPOSE: Hypothalamic hamartoma (HH) related epilepsy presents with gelastic seizures (GS), other seizure types and cognitive deterioration. Although seizure origin in GS has been well established, non-GS are poorly characterized. Their relationship with the HH and cognitive deterioration remains poorly understood. We analyzed seizure type, spread pattern in non-GS and their relationship with the epileptic syndrome in HH. METHODS: We documented all current seizure types in six adult patients with HH-epilepsy with video-EEG monitoring, characterized clinical-electrographic features of gelastic and non-gelastic seizures and correlated these findings with cognitive profile, as well as MRI and ictal SPECT data. RESULTS: Only four seizure types were seen: GS, complex partial (CPS), tonic seizures (TS) and secondarily generalized tonic-clonic seizures (sGTC). An individual patient presented either CPS or TS, but not both. GS progressed to CPS or TS, but not both. Ictal patterns in GS/TS and in GS/CPS overlapped, suggesting ictal spread from the HH to other cortical regions. Ictal SPECT patterns also showed GS/TS overlap. Patients with GS-CPS presented a more benign profile with preserved cognition and clinical-EEG features of temporal lobe epilepsy. Patients with GS-TS had clinical-EEG features of symptomatic generalized epilepsy, including mental deterioration. CONCLUSIONS: Video-EEG and ictal SPECT findings suggest that all seizures in HH-related epilepsy originate in the HH, with two clinical epilepsy syndromes: one resembling temporal lobe epilepsy and a more catastrophic syndrome, with features of a symptomatic generalized epilepsy. The epilepsy syndrome may be determined by HH size or by seizure spread pattern.