Alcohol utilization and dependence with special reference to protein level in a liquid diet for rats

Experiments were carried out with a nutritionally balanced diet to test the response of rats to levels of ethanol between 0% and 6%, and to different levels and sources of protein and amino acid supplements in relation to alcohol utilization and withdrawal seizures. The high-calorie/high-carbohydrate liquid diet was well tolerated when the alcohol level was less than 30% of total calories, or 4.5% of diet. When alcohol was provided at 6% of diet, or 33% of total calories, growth and withdrawal seizure rates were negatively affected in comparison with the lower ethanol levels, even though ethanol consumption (in g/kg/day) was not different. The 6% alcohol diet was then altered through the addition of more protein calories, from 13% to 20%. This supplementation improved growth rate of the animals and reduced the rate of withdrawal seizures. The improvement from the additional protein was observed with both casein and soy protein, and was not attributable to any one or even several amino acids that might serve as transmitter precursors. A mixture of all essential amino acids representing the difference in amino acids between 13% and 20% casein protein calories was an effective as the equivalent amount of intact protein. The nonessential amino acids equivalent to 7% casein protein calories, when added to the 13% protein calories diet, increased the rate of withdrawal seizures, presumably by exacerbating the protein deficiency in the 13% protein diet. It was concluded that a 1000-1200 kcal/kg diet with 20% kcal from protein and 50% kcal from carbohydrate provides an optimal nutrient balance for efficient utilization of a 6% ethanol liquid diet for rats.

Amphetamine and fenfluramine suppress ethanol intake in ethanol-dependent rats

Alcohol intake or preference for alcohol has been attributed to concomitant dopamine and serotonin dysfunction in rats. Amphetamine and fenfluramine, administered alone, have been shown to reduce food and fluid intake as well as alcohol consumption while acute coadministration of these agents has been shown to suppress audiogenic seizure in rats withdrawn from alcohol. The present study was designed to assess the effectiveness of chronic amphetamine and fenfluramine coadministration on reducing alcohol intake. Chronic coadministration of amphetamine (2 mg/kg) and fenfluramine (8 mg/kg) reduced alcohol consumption during choice trials in both alcohol-dependent and alcohol-nondependent rats while not affecting water intake. The findings indicate that coadministration of amphetamine and fenfluramine, a treatment effective in reducing alcohol withdrawal seizures, also selectively attenuates alcohol consumption.

A natural kinase-deficient variant of fibroblast growth factor receptor 1

A fibroblast growth factor receptor 1 variant missing 37 amino acids from the carboxy-terminal tyrosine kinase catalytic domain was discovered in human lung fibroblasts and several other human cell lines. The receptor variant binds specifically to acidic fibroblast growth factor but has no tyrosine kinase activity. It was found that cellular transfectants expressing the fibroblast growth factor receptor 1 variant are mitogenically inactive and ligand binding to the receptor causes neither receptor autophosphorylation nor phospholipase C-gamma transphosphorylation. The fibroblast growth factor receptor 1 variant therefore represents an inactive receptor for acidic fibroblast growth factor. Since both kinase and kinase-deficient receptor forms are expressed in cells, it is conceivable that the kinase-deficient receptor plays an important role in regulating cellular responses elicited by acidic fibroblast growth factor stimulation.

[Serotype distribution and antimicrobial susceptibility of group A streptococci (Streptococcus pyogenes) isolated in Taiwan]

T-protein serotypes and antimicrobial susceptibility of a total of 139 group A streptococci (GAS) strains isolated in Taiwan area in 1993 and during the outbreak of scarlet fever in 1994 were analyzed. All strains were T-typable, and T12 (42.46%) and T4 (38.85%) were the dominant T types. According to the results of analysis of antimicrobial susceptibility, all GAS strains were divided into 9 resistotypes, A (all susceptible), B (resistant to tetracycline), C (resistant to erythromycin and tetracycline), D (resistant to chloramphenicol and tetracycline), E (resistant to chloramphenicol and clindamycin), F (resistant to chloramphenicol, clindamycin and tetracycline), G (resistant to clindamycin, erythromycin and tetracycline), H (resistant to chloramphenicol, clindamycin, erythromycin and tetracycline), and I (resistant to chloramphenicol, clindamycin, erythromycin, tetracycline and vancomycin). Type B (37.42%) was the dominant type. Type A (25.91%), and type H (26.63%) also appered with high incidence. Most of strains isolated from Mid-Taiwan were type H. Only one strain, that was isolated in I-lan, was resistant to vancomycin, in addition to resistant to chloramphenicol, clindamycin, erythromycin, and tetracycline. All strains were susceptible to penicillin G, ampicillin, and ceftriaxone. Some strains were resistant to chloramphenicol (32.38%), clindamycin (30.22%), erythromycin (31.66%), tetracycline (73.39%), and vancomycin (0.70%). During the outbreak of scarlet fever in 1994, the dominant T types of strains isolated in North-Taiwan and Mid-Taiwan were T4 and T12, respectively, and the major resistotypes of those strains were B and H types, respectively. These clues suggested that the outbreaks occurring in North-Taiwan and Mid-Taiwan may have no epidemiological linkage between each other.

[Comparison of immunoassay kits for detection of staphylococcal enterotoxins produced by Staphylococcus aureus]

Four commercial kits, SET-RPLA, RIDASCREEN, SET-EIA, and TECRA, were compared for the efficiency of detecting staphylococcal enterotoxins (SE). There was no non-specific reaction for detection of SE produced by 21 Staphylococcus aureus strains from 5 outbreaks of food poisoning using SET-RPLA, SET-EIA and TECRA kits. The background of the results of RIDASCREEN kit was high and non-specific reactions were present in some strains.

IN CONCLUSION

(i) TECRA kit is suggested to be used for screening SE producing strains; (ii) SET-RPLA and RIDASCREEN kits are suitable for epidemiological investigation of SE types, but the lack of ability for detecting SEE, long time required for testing with SET-RPLA kit and high background when using RIDASCREEN kit must be overcome; and (iii) because of the complicated test procedures and the lack of ability for detecting SEE, the practicality of SET-EIA kit in screening and epidemiological research purposes is low.

Diet composition, alcohol utilization, and dependence

Experiments were carried out in which a nutritionally balanced liquid diet previously used in this laboratory was modified as to total calorie content and high or low carbohydrate and fat concentration. Ethanol was added at 4.5% and 6.2% of diet weight and provided either 27% or 34-37% of total calories depending upon the changes in nutrient content. Measurements included 8-day food/calorie and ethanol consumption, plasma ethanol level, liver alcohol dehydrogenase (ADH) activity, and rate of audiogenic-induced withdrawal seizures. The original liquid diet with 4.5% ethanol was consumed in significantly lesser amounts than the alcohol-free diet, and essentially no body weight gain occurred, regardless if the major nonalcohol, nonprotein calorie source was fat or carbohydrate. When the calorie content of the diet was boosted through the addition of extra carbohydrate or fat (at the expense of water), appreciable weight gain was noted; in the case of the higher calorie diet boosted with more carbohydrate (maltodextrin) calories, growth was similar to that observed on the alcohol-free control diet. On this latter diet ethanol calories appeared to be utilized close to their theoretical value of 7 kcal/g. Blood alcohol levels were significantly higher on the lower calorie diets and were lowest on the high-calorie, high-carbohydrate, 4.5% ethanol diet. This diet also allowed for the lowest rate of withdrawal seizures despite an ethanol intake that was as high as on the lower calorie diets. Essentially, no differences were noted among ADH activities for the dietary treatments studied and thus, did not explain the differences observed among blood ethanol levels. When the alcohol concentration in the high-carbohydrate, high-calorie diet was raised to 6.2% from 4.5% to provide 34% of total calories, the rats responded by decreasing their food (and alcohol) intake to the same level as did the animals receiving a much lower calorie diet, but with 37% of caloric alcohol content. This suggests that at a diet alcohol concentration of 34-37%, one or more nutrient metabolites become limiting in the utilization of ethanol, resulting in food intake adjustments that maintain similar amounts of alcohol consumption.

Motor neuron disease in Hong Kong Chinese: epidemiology and clinical picture

This study documents the clinical features, incidence and prevalence of motor neuron disease (MND) in Hong Kong Chinese. Patients with MND who were alive between 1989 and 1992 were recruited by retrieval of medical records from the four major hospitals in Hong Kong, and by referral of neurologists, neurosurgeons and medical consultants. Mortality statistics was provided by the Census and Statistics Department. A total of 84 cases were identified with a male preponderance of 1.98:1. The average annual period incidence was 0.31/100,000 and the point prevalence on December 31, 1992, was 0.95/100,000. The mean age at onset was 55.5 years (range 19-81) with a peak observed from 55 to 65 years. The clinical features are similar to other reported series of MND. The incidence and mortality of MND in Hong Kong are therefore lower than the worldwide figures of 2.0/100,000 and 1.5/ 100,000, respectively.

Low-molecular-weight heparin for the treatment of acute ischemic stroke

BACKGROUND

Despite doubts about their efficacy and concern about their safety, antithrombotic agents are often used to treat acute ischemic stroke. Recent experience in patients with other thromboembolic disorders suggests that low-molecular-weight heparin, which requires only subcutaneous administration once or twice daily, may be more effective and safer than standard (unfractionated) heparin.

METHODS

We conducted a randomized, double-blind, placebo-controlled trial comparing two dosages of low-molecular-weight heparin with placebo in the treatment of ischemic stroke. Patients were randomly assigned within 48 hours of the onset of symptoms to receive high-dose nadroparin (4100 anti-factor Xa IU twice daily), low-dose nadroparin (4100 IU once daily), or placebo subcutaneously for 10 days. The primary measure of outcome was death or dependency regarding activities of daily living six months after randomization. Secondary outcomes were death, hemorrhagic transformation of the infarction, and other complications at 10 days, and death or dependency at 3 months.

RESULTS

A total of 2750 patients were screened for the study. Among 312 patients randomized, 306 had outcomes that were analyzed at six months. Forty-five patients (45 percent) in the high-dose group, 53 patients (52 percent) in the low-dose group, and 68 patients (65 percent) in the placebo group died or became dependent. There was a significant dose-dependent effect among the three study groups in favor of low-molecular-weight heparin (P = 0.005 by the chi-square test for trend). No significant differences among the groups in the occurrence of secondary outcomes were observed at 10 days.

CONCLUSIONS

For patients with ischemic stroke treated within 48 hours of the onset of symptoms, low-molecular-weight heparin was effective in improving outcomes at six months.

Novel synergistic treatment of ethanol withdrawal seizures in rats with dopamine and serotonin agonists

A recent observation in this laboratory of a simultaneous increase in striatal dopamine and a decrease in serotonin in ethanol-dependent rats during ethanol withdrawal prompted studies with combined dopaminergic + serotoninergic agonists to stop withdrawal seizures. Amphetamine (2 mg/kg) + fenfluramine (8 mg/kg) given jointly, but not separately, prevented ethanol withdrawal seizures as effectively as benzodiazepines (chlordiazepoxide), the current drugs of choice. The combination of amphetamine and fenfluramine, unlike chlordiazepoxide, significantly reduced intake of ethanol during and immediately following ethanol withdrawal.

DNA analysis of Huntington's disease in southern Chinese

Allelic frequencies of RFLPs at loci closely linked to the HD gene, D4S95, D4S91, D4S141, and D4S90, were determined in 13 Huntington's disease (HD) patients from nine Chinese families and 129 normal subjects. These were similar for non-HD and HD chromosomes and the HD gene in Chinese is associated with multiple haplotypes. Hence the HD gene probably arose independently in the background haplotypes of the Chinese population. The heterozygosity rates for the two most useful RFLP sites are 0.659 for D4S95-AccI VNTR and 0.494 for D4S141-HindIII. (CAG)n repeat numbers ranged from 12 to 27 in 174 normal chromosomes. In 52 meiotic recombinations, the (CAG)n repeats were stably inherited in normal families. In HD families, 12 of 13 HD patients had expanded (CAG)n repeats of 40 to 58. Additionally, 10 asymptomatic family members had expanded (CAG)n repeats and the inheritance of the expanded repeat was unstable in these families.

Influence of gonadal hormones on sexual differences in sensitivity to methamphetamine-induced neurotoxicity

The administration of high doses of methamphetamine to mice causes long-lasting depletions of striatal dopamine to a greater extent in males than in females. Likewise, the incidence of Parkinson's disease is higher in males than in females. The present study investigated the roles of estrogen and testosterone in mediating the dopamine depletion induced by methamphetamine. Male and female mice received four cumulative SC doses of methamphetamine (10 mg/kg) at two hour intervals and were sacrificed two weeks later for HPLC analysis of striatal monoamines. Intact male mice were found to have a 76% dopamine depletion, which was significantly greater than the 37% depletion exhibited by the intact female mice. Neither removal of the ovaries nor removal of the testes one month prior to the methamphetamine treatment significantly changed the magnitude of the methamphetamine-induced dopamine depletion. Thus, the reduced sensitivity of female mice to methamphetamine may be independent of physiological gonadal hormones.

The morphologic changes of endometrial spiral arterioles in IUD-induced menorrhagia

To investigate the relationship between IUD-induced menorrhagia and spiral arteriolar function, we examined the endometrium under light and electron microscope on samples obtained within 24 hours after the onset of premenstrual spotting. These samples included an IUD bleeding group (20 cases), an IUD non-bleeding group (20 cases) and an IUD non-user group (10 cases) as controls. Compared with the IUD non-user group the degenerative changes of spiral arteriolar wall were more severe and dilation of the spiral arteriolar lumen was more obvious, especially in the spongeous layer. In the IUD non-user group these changes were mild, suggesting that IUD-induced menorrhagia might be correlated with poor contractility of spiral arterioles in the spongeous layer.

Psychosocial impact of Huntington's disease on Hong Kong Chinese families

Twenty-eight asymptomatic relatives from 7 Chinese families with Huntington's disease (HD) received psychosocial assessment. One third of these subjects (n = 9) had symptoms of anxiety and depression that warranted a Present State Examination (PSE) diagnosis. One quarter of these subjects (n = 8) would contemplate suicide if their predictive testing indicated a high risk of having the disease. This suicidal risk was associated with a PSE diagnosis of depression and a stress-coping repertoire with a high proportion of coping strategies of the avoidance type at the time of interview. Early and close liaison with these subjects for the detection of mental symptoms and provision of counselling on a balanced and positive coping style is essential.

Management of Tetanus: A Review of 18 Cases

Eighteen patients with generalized tetanus seen during an 8-year period in three regional hospitals in Hong Kong are reviewed. Eighty-nine per cent of the patients were intravenous heroin addicts who developed a severe type of generalized tetanus with autonomic dysfunction. Pain or stiffness of the neck or back was the commonest presenting symptom, followed by trismus and dysphagia. Most of the patients developed muscle spasms within 24 h of the onset of presenting symptoms. Early ventilatory support and tracheostomy, together with intensive nursing care, were the mainstay of the treatment. Pulmonary and gastrointestinal complications were common during the course of illness and treatment of autonomic dysfunction was often unsatisfactory. The case fatality rate was 25% among the heroin addicts, but full recovery was the usual outcome for those who survived. The simultaneous administration of intrathecal tetanus immunoglobulin tends to reduce mortality.

Huntington's disease in Hong Kong Chinese: epidemiology and clinical picture

In a territory-wide survey of Huntington's disease (HD) in the Chinese population of Hong Kong, 20 patients from 11 families were identified from 1984 to 1991, giving a low period prevalence of 3.7 per 10(6) population. Six patients had died by 1991, hence the point prevalence was even lower, being 2.5 per 10(6) population. The male to female ratio was 3:1. No paternal transmission effect on the age of onset was observed. Apart from these differences, the clinical and pathological features were similar to those seen in the West.

Restrictive fragment length polymorphisms of markers 3'HVR and 24-1 and their applications in gene diagnosis of adult polycystic disease in Chinese

Adult polycystic kidney disease was diagnosed with pedigree analysis using polymorphic DNA markers linked to the disease gene in 5 families. The markers were thoroughly characterized in the population. We noted two important markers, 3'HVR and 24-1, which flank the disease gene PKD1 in normal Chinese. Southern hybridization was used, and numerous 3'HVR/PvuII polymorphic allelic bands varied from 1.4 kb to 8.0 kb with a positive skew distribution. They were divided into 11 groups with an interval of 0.6 kb and a heterozygosity rate of 0.86. Allele frequencies were observed. When the probe 24-1 was hybridized with genomic DNA digested by TaqI, two alleles, B1 and B2, were detected with frequencies of 0.76 and 0.24, respectively. B1 was 3.8 kb in size and B2 was composed of 2 bands, 1.5 kb and 1.3 kb. The polymorphism information content was found to be 0.297. Using these two markers for linkage analyses of 5 affected families, we confirmed the linkage between 3'HVR and the disease gene PKD1 and made presymptomatic diagnosis of the members at risk.

Investigation of nimodipine pharmacokinetics in Chinese patients with acute subarachnoid haemorrhage

Nimodipine pharmacokinetics was investigated in 12 Chinese patients with acute subarachnoid haemorrhage receiving an IV infusion of 1.6 or 2 mg/h (based on estimated body weight) for 10 days. Peripheral venous blood samples were collected for up to 4 days and plasma nimodipine was assayed by GC/ECD. The mean value was taken as the steady state concentration (Css) and Clearance (CL) (hourly dose/Css) was calculated. Eight survivors were given oral nimodipine (60 or 90 mg) every 6h (based on body weight), blood was sampled over 6 h and the plasma nimodipine level determined. The values for Css, CL and CL.kg-1 were 33.5 micrograms.l-1, 58 l.h-1 and 1.0 l.h-1 x kg-1 respectively; in survivors receiving the drug orally, bioavailability of the 30 mg tablet was 9%. In one very sick patient given crushed tablets by naso-gastric tube, the AUC was very low; in vitro studies indicated that adsorption of nimodipine by the tubing was unlikely to have been the cause. The pharmacokinetic findings in Chinese patients are comparable to previously reported values in Caucasians.

Growth factor gene expression in lung fibroblasts

A lung fibroblast cell line was isolated from lung biopsy of a patient with lung fibrosis. Gene expression of ten growth factors in the fibroblasts were investigated by a reverse transcription-DNA polymerase chain reaction. The results indicated that the fibroblasts expressed acidic fibroblast growth factor (aFGF) mRNA transcript. Further experiments revealed that recombinant aFGF could be internalized by the fibroblasts and stimulated the proliferation of the cells. These data suggest that aFGF may activate lung fibroblasts in a way of autocrine and, therefore, may be involved in the development of lung fibrosis.

Treatment of acute cortical infarct with intravenous glycerol. A double-blind, placebo-controlled randomized trial

BACKGROUND AND PURPOSE

This clinical trial investigates the effectiveness of intravenous glycerol therapy in patients with acute cortical infarction in whom intracerebral hemorrhage was rigorously excluded.

METHODS

Within 48 hours of symptoms from their first ischemic stroke, 113 hospital inpatients were randomized into the trial, provided that hemorrhage was excluded by computed tomography and informed consent was obtained. Patients were stratified into alert, semicoma, and coma groups using the Glasgow Coma Scale. Treatment was allocated according to a double-blind, randomized protocol; 56 patients received 500 mL of 10% glycerol in saline over 4 hours on 6 consecutive days, and 57 patients received corresponding placebo treatment with saline. Using a variety of objective scoring systems, patient follow-up was up to 6 months.

RESULTS

Corresponding measures of outcome in the glycerol and placebo groups were similar. At 6 months, respective mortality rates were 17 of 56 and 16 of 57, and mean +/- SD improvements in scores were 9.98 +/- 14.40 vs 10.51 +/- 12.68 (long-term), 1.12 +/- 7.20 vs 1.57 +/- 6.30 (prognostic), -1.94 +/- 5.53 vs -2.06 +/- 5.34 (Glasgow Coma Scale), and 21.72 +/- 23.40 vs 11.94 +/- 18.10 (Barthel Index rating in survivors). Hemolysis (generally subclinical) was the only adverse effect.

CONCLUSIONS

There was no clinically or statistically significant difference in outcome between the groups; a trend toward greater functional recovery among survivors was evident after treatment with glycerol.

N-hexane neuropathy in offset printers

In an offset printing factory with 56 workers, 20 (36%) developed symptomatic peripheral neuropathy due to exposure to n-hexane. Another 26 workers (46%) were found to have subclinical neuropathy. The initial change in the nerve conduction study was reduced amplitude of the sensory action potentials, followed by reduced amplitude of the motor action potentials, reduction in motor conduction velocities and increase in distal latencies. These changes indicate primary axonal degeneration with secondary demyelination. Sural nerve biopsy in a severe case showed giant axonal swellings due to accumulation of 10nm neurofilaments, myelin sheath attenuation and widening of nodal gaps. The development of neuropathy bore no direct relationship to the duration of exposure, hence factors such as individual susceptibility may be important. Optic neuropathy and CNS involvement were uncommon and autonomic neuropathy was not encountered.

Myocardial infarction complicating postsplenectomy thrombocytosis, with early left ventricular mural thrombus formation and cerebral embolism--a case report

Thrombocytosis is a rare cause of ischemic cardiovascular and cerebrovascular events in patients with intrinsically normal coronary and cerebral vasculature. This report details the occurrence of inferior wall myocardial infarction (MI) consequent upon postsplenectomy thrombocytosis in a thirty-four-year-old man with angiographically normal coronary arteries. The MI was complicated by early left ventricular mural thrombus formation and embolic cerebral infarction. Combined anticoagulant and antiplatelet therapy was required to prevent the recurrence of ischemic events.

TNF alpha mRNA expression in bronchoalveolar lavage cells from patients with lung fibrosis and TNF alpha activity in the lavage supernatants

Tumor necrosis factor alpha (TNF alpha) mRNA expression in bronchoalveolar lavage (BAL) cells from patients with lung fibrosis was studied by a reverse transcription-DNA polymerase chain reaction (RT-PCR). The results indicated that two thirds of the tested samples were TNF alpha mRNA positive. On the other hand, TNF alpha activity was detected in a big part of the BAL supernatants from the patients. Furthermore, recombinant TNF alpha was found to be mitogenic to lung fibroblasts. These data suggest that TNF alpha expression in BAL cells may play a role in the development of lung fibrosis in human.

HLA-DPB1 alleles correlate with risk for multiple sclerosis in Caucasoid and Cantonese patients lacking the high-risk DQB1*0602 allele

Multiple sclerosis (MS) is a demyelinating disease associated with the HLA-DR2-related haplotype DRB1*1501, DQB1*0602 in Caucasoids and with DQB1*0602 in DR2-positive Cantonese. However, many MS patients do not have the high-risk HLA-D determinants and alternative genes may contribute to the pathogenesis of MS. One candidate gene is HLA-DPB1. Our reanalysis of five earlier reports of HLA-DPB1 antigen distributions in Caucasoid MS patients shows a consistent and highly significant increase (p = 1.5 x 10(-5)) in frequency of HLA-DPw3 in the combined data set. This study tests whether HLA-DPw3 (DPB1*0301) is also increased in frequency in Australian and Cantonese MS patients and whether any distortion in DPB1 allelic distributions can be attributed to linkage disequilibrium with DQB1*0602. PCR-RFLPs were used to determine distributions of 20 HLA-DPB1 alleles in 41 Australian MS patients and 67 controls of known DQB1*0602 status and in 11 Cantonese MS patients and 33 controls positive for HLA-DR2. HLA-DP distributions in Australian MS patients and controls positive for DQB1*0602 did not differ, but in those MS patients lacking DQB1*0602, the DPB1*0301 antigen (phenotype) frequency was significantly (p = 0.006) increased (50.0%) when compared with DQB1*0602-negative controls (9.1%). DPB1*0301 was associated (p = 0.003) with DQB1*0402 (DR8) in Caucasoid MS patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Vascular pseudoparkinsonism

Vascular pseudoparkinsonism may be confused with idiopathic Parkinson's disease. Patients may be unnecessarily treated with anti-parkinsonian drugs while their underlying vascular disease is ignored. We investigated 250 parkinsonian patients seen in our Movement Disorders Clinic for a possible vascular etiology. After excluding those with a known secondary cause such as drug-induced parkinsonism, progressive supranuclear palsy, multiple system atrophy and hyperparathyroidism, brain computed tomography and/or magnetic resonance imaging were performed on those who showed poor or no response to levodopa. In those with an ischemic lesion demonstrated on neuroimaging, anti-parkinsonian drugs were stopped and the patients were reassessed. Eleven patients (4.4%) had ischemic brain lesions accounting for their parkinsonism. All were initially diagnosed as Parkinson's disease because of the prominence of bradykinesia and rigidity. Gait disturbance was also common, but resting tremor was distinctly absent. Three anatomical patterns with different prognosis were identified. Three patients with basal ganglia lacunar infarct recovered spontaneously, three with frontal lobe infarcts remained static and five with periventricular and deep subcortical white matter lesions had progressive deterioration. Autopsy in one patient confirmed bilateral frontal lobe watershed infarcts and the absence of brain stem Lewy bodies. Parkinsonian patients with poor or no response to levodopa therapy should be investigated for a vascular etiology.

Myasthenia gravis in Hong Kong Chinese. 1. Epidemiology and adult disease

A territory-wide study of myasthenia gravis (MG) was conducted in Hong Kong. Two hundred and sixty-two Chinese patients (159 adult and 103 paediatric onset) were identified, corresponding to a point prevalence and period prevalence of 53.5 and 62.2 per million respectively, and an average annual incidence of 4.0 per million population. Nine patients died, 7 from MG, giving a case fatality rate of 0.027. Female predominance was present in the whole group of patients (female to male ratio 1.6:1) and in those with adult disease (ratio 2.1:1), but not in those with onset in childhood (ration 1.1:1). Onset of disease was most common in the first 3 decades of life, and became less common in subsequent decades. Juvenile onset MG occurred in 39.3% of patients and restricted ocular MG in 47.9%. Familial occurrence was found in 5 patients. In the 159 adult onset patients, ocular disease was most common (32.7%), followed by mild generalised (29.6%), moderately severe generalised (24.5%), fulminating (11.9%) and late severe disease (1.3%). The mean age of onset of symptoms was 36.7 years. The symptomatology was similar to that of Caucasoid populations. Autoimmune thyroid disease was the commonest associated disease, and the incidence of thymoma among thymic abnormalities was high at 38%.