Restless legs syndrome in Parkinson's disease

INTRODUCTION

Recent clinical and functional imaging data suggest impaired central dopaminergic transmission in restless legs syndrome (RLS). As RLS responds to dopaminergic medications, an etiologic link between RLS and Parkinson's disease (PD) has been proposed. However, few studies have examined this association.

OBJECTIVE

To investigate the prevalence of RLS amongst PD outpatient population.

METHOD

The prevalence of RLS was determined by the diagnostic criteria of the International Restless Legs Syndrome Study Group (IRLSSG). Consecutive PD patients (n=125) were prospectively evaluated in our clinic.

RESULTS

There were 77 (61.6%) males and 48 (38.4%) females with a mean age of 65.1+/-9.3 (SD) years (range 34-83), and mean age of onset of disease at 59.6 years+/-10.7 (SD) years (range 30-81). Nineteen (15.2%) patients had motor restlessness. Of these, one (0.8%) patient had RLS-like symptoms closely correlated to wearing "off" effect of levodopa. None of the patients satisfied the IRLSSG diagnostic criteria of RLS. This was not significantly different compared to the 0.6% and 0.1% RLS prevalence in our general population and clinic population.

CONCLUSIONS

Our study demonstrates that motor restlessness was present in 15.2% of our PD patients. However, prevalence of RLS in our PD patients was not significantly different from our general population or clinic population, suggesting that these two diseases may not share the same pathophysiologic mechanism.

Diffusion weighted MR imaging in acute stroke: the SGH experience

Cerebrovascular accident (CVA) is a leading cause of death and disability in many countries. Diffusion-weighted (DW) magnetic resonance (MR) imaging has been reported to be useful in the detection of acute strokes and as an investigative tool evaluating the therapeutic effects of neuroprotective and thrombolytic agents. The objectives of this study are to share our experience using the commercially available isotropic DW scan in imaging of acute stroke, assess its usefulness over conventional T2-weighted (T2W) scans in a busy clinical radiology unit and highlight it pitfalls. We found the rapid sub-minute DW technique well suited for ill and restless stroke patients and superior to T2W scans in many ways. It was highly sensitive to acute ischaemic lesions, made lesions easily identifiable and readily differentiated the acute lesion from a background of multiple chronic infarcts. However, there are potential pitfalls in the evaluation of small hyperacute posterior fossa strokes and venous infarcts. The major strength of this MR technique lies in its ability to diagnose hyperacute strokes and thence the potential for therapeutic thrombolysis, but unfortunately patients qualifying for the "therapeutic window" were a minority. More efforts need to be focused on public education in order for this powerful imaging modality to find its true value and contribute to viability of an effective thrombolytic programme.

Evaluation of somnolence in Parkinson's disease: comparison with age- and sex-matched controls

The authors found a significantly higher prevalence of daytime somnolence in 201 patients with PD compared with 214 age- and sex-matched healthy control subjects (Epworth Sleepiness Scale score 5.6 vs 4.6). The prevalence of "sleep attacks" (SA) was about seven times higher in patients with PD than in control subjects (13.9% vs 1.9%; p < 0.0005). Multivariate analysis demonstrated that a higher dose of levodopa and longer duration of disease significantly predicted for SA in patients with PD. Epworth Sleepiness Scale scores of > or =10 had 71.4% sensitivity and 88.4% specificity for SA.

Helical computed tomography of the abdomen: evaluation of image quality using 1.0, 1.3, and 1.5 pitches

BACKGROUND

The purpose of this study was to investigate whether trained radiologists can distinguish minor differences among computed tomography (CT) images of extended helical pitches of 1.0 to 1.5.

METHODS

Between September 2000 and February 2001, 72 patients were randomized into 1 of 3 equal groups: helical pitches of 1.0, 1.3, and 1.5. The imaging parameters of all patients were kept constant. Twelve of the 72 patients were excluded because of various pathological conditions. In a total, 60 examinations were enrolled in the evaluation study. Three radiologists blinded to the image parameters were asked to independently evaluate 9 normal structures and overall images of 60 studies using a scale from 1 (worst) to 5 (best).

RESULTS

There were no statistically significant differences in evaluation of image quality among helical pitches 1.0, 1.3, and 1.5 of abdominal CT when assessing 9 normal structures and overall images independently (p > 0.05).

CONCLUSIONS

Abdominal CT performed with helical pitches of 1.0, 1.3, and 1.5 were equivalent in this study. With the use of a helical pitch greater than 1, clinicians can benefit from increased scan coverage in less time and with less radiation than can be achieved with standard helical pitch-1.0 protocols.

Oral stereognosis in stroke and Parkinson's disease: a comparison of partially dentate and edentulous individuals

Oral stereognosis was measured in partially dentate and edentulous patients with stroke, Parkinson's disease, and an age and gender-matched control group. Stereognostic tests involving conventional free intra-oral manipulation of test objects were undertaken in the partially dentate and edentulous with and without complete dentures. Comparisons were made using the unpaired t-test and ANOVA. Edentulous stroke patients without dentures had significantly greater error scores and fewer correct identifications compared with partially dentate stroke patients. Stereognostic measures were similar in the partially dentate and edentulous with dentures, within experimental groups. In the partially dentate, there were no differences in stereognostic measures between the three groups. Stereognostic measures were poorer in edentulous stroke patients with and without dentures compared with the edentulous control group. Partially dentate stroke patients are less likely to have impaired oral stereognosis than edentulous stroke patients.

Utilization of dental services in Southern China

A population's utilization of dental services is an important parameter in oral health care planning, which has rarely been studied in China. The objectives of this report were to describe the dental service utilization pattern of middle-aged and elderly Chinese and to analyze the influence of selected variables on the use of dental services. A Guangdong Province population of 1,573 35- to 44-year-olds and 1,515 65- to 74-year-olds recruited from urban and rural communities was interviewed in their local dialect. It was found that 23% of the middle-aged and 24% of the elderly subjects had visited a dentist within the preceding year. The two most commonly cited reasons for not having seen a dentist for at least 3 years were: no perceived need, and no serious dental problems. Among subjects who had visited a dentist within 3 years, the 3 most commonly received treatments were: fillings, extractions, and dental prostheses. Furthermore, a logistic regression analysis showed that women, subjects who lived in urban areas, were better educated, were wealthier, and had better oral health knowledge were more likely to be a recent dental service user. In conclusion, dental service utilization among the adult Southern Chinese was found to be low, problem-driven, and influenced by some socio-economic factors.

An Oral Health Survey in Southern China, 1997: background and methodology

Relatively limited information is available about the oral health in the Guangdong Province of Southern China, the closest neighbor to Hong Kong. The study intended to explore the oral health status, knowledge, attitudes, and dental care utilization in the Guangdong population as a basis for formulating strategies for oral health prevention and treatment. Through multi-stage stratified and quota-sampling, individuals from urban as well as rural communities were selected (5- to 6-; 12-; 35- to 44-; and 65- to 74-year-olds; total N = 6251). Structured interviews and clinical examinations were performed. Inter-examiner reliability was high (kappa = 0.60-0.96). Samples of community water were taken for fluoride assessment. Overall, the sample surveyed was acceptably representative of the population, with some under-representation of rural residents and agricultural workers. Re-weighting was performed in appropriate analyses. The data analysis model used in the Second International Collaborative Study was used as a guide for the present data analysis. This approach has not previously been used on a Mainland Chinese population.

Oral health knowledge, attitudes, and practices of Chinese adults

Only recently have behavioral aspects been taken into consideration in oral health studies in China; thus, relevant information on perceptions in adult Chinese about oral health care is inadequate. In 1996-97, a large-scale oral epidemiological study was conducted in Southern China. Among its objectives were to describe the oral health knowledge, attitudes, and practices of the urban and rural adults living in Southern China and to analyze the influence of selected demographic and socio-economic factors. From 8 urban and 8 rural communities in Guangdong Province, 1,573 35- to 44-year-olds and 1,515 65- to 74-year-olds were sampled. Specially trained interviewers from the staff of local government or hospitals conducted face-to-face structured interviews. Almost all of the middle-aged and more than 90% of the dentate elderly surveyed claimed that they brushed their teeth every day and used toothpaste during toothbrushing, but awareness about fluoride content was lacking. The respondents had poor oral health knowledge but positive attitudes toward oral health, providing a basis for more community-based oral health education programs, especially targeting adults who are less-well-educated and have fewer socio-economic advantages.

Coronal and root caries in Southern Chinese adults

Southern China is the most prosperous part of China, but information useful for oral care planning is very limited. A large-scale epidemiological survey was conducted in 1996-97. The objectives of this report were to describe the coronal and root caries of the adult Southern Chinese and to analyze the influence of selected demographic and socio-economic factors on the disease pattern. A total sample of 1,573 35- to 44-year-olds and 1,515 65- to 74-year-olds from 8 urban and 8 rural survey sites in Guangdong Province participated in an oral health interview and underwent clinical examination. World Health Organization examination procedures and diagnostic criteria were used. The weighted mean DMFT scores of the middle-aged and the elderly subjects were 4.8 and 16.1, respectively. People living in rural areas had a higher DMFT score than those living in urban areas (4.9 vs. 4.3 in the 35- to 44-year-olds and 16.5 vs. 14.7 in the 65- to 74-year-olds). In both age groups, MT was the major component of the DMFT score. Analysis of covariance showed that women and those who were economically less well off had higher DMFT scores in both age groups. The weighted prevalence rates of decayed/filled roots were 12% and 37%, with a mean of 0.2 and 0.7 teeth affected, in the middle-aged and the elderly, respectively. In conclusion, socio-economic factors had a considerable effect on the dental caries status of adults in Southern China.

Periodontal conditions in adult Southern Chinese

Periodontal diseases remain a concern in adult populations, but there have been no systematic descriptions of periodontal conditions, which have included periodontal attachment loss, among Southern Chinese. The main aim of this report is to describe the periodontal conditions in adult Chinese and to investigate factors that may have influenced periodontal attachment loss. Subjects were recruited from urban and rural survey sites throughout Guangdong. In total, 1,572 35- to 44-year-old subjects and 1,286 65- to 74-year-old subjects completed a structured interview and underwent a periodontal examination, which included the Community Periodontal Index (CPI) and periodontal Attachment Loss (ALoss) recordings. Calculus was found as the highest CPI score in 61-68% of the 35- to 44-year-old subjects and in 54-57% of the 65- to 74-year-olds. Shallow pockets were found as the highest CPI score in about one-third of both the urban and the rural subjects in both age groups, and deep pockets in 3-7% of the subjects. ALoss was more prevalent than pockets in both age groups. On the basis of the ALoss recordings, about one-third of the subjects in both age groups were categorized as exhibiting considerable ALoss for their age. In both age groups, logistic regression analysis indicated that being male, wearing partial dentures, and reporting less frequent toothbrushing were found to be associated with considerable ALoss.

Restless legs syndrome in an Asian population: A study in Singapore

In face-to-face interviews, we examined 157 consecutive individuals aged 55 years and older, selected from the general population in Singapore, and 1,000 consecutive individuals aged 21 years and older, from a primary healthcare center. Based on the IRLSSG criteria, the prevalence of restless leg syndrome (RLS) was 0.6% and 0.1%, respectively.

Oral health status and oral health behaviors in Chinese Children

The objectives of the study were to describe the oral health status and treatment needs of the 5- to 6-year-old and 12-year-old children in Southern China; to describe the patterns of oral health behaviors, knowledge, and attitudes among the 12-year-olds; and to assess the effects of socio-behavioral factors on the 12-year-old children's dental caries experiences. The study sample was comprised of 1,587 5- to 6-year-old and 1,576 12-year-old urban and rural schoolchildren living in Guangdong Province. Three calibrated dentists clinically examined the children, and trained interviewers interviewed the 12-year-olds. Caries prevalence of the 5- to 6-year-old children was high (urban 78% vs. rural 86%); the mean dmft of the urban and rural children was 4.8 and 7.0, respectively. The caries prevalence and mean DMFT score of the 12-year-olds were 41% and 0.9 (urban) and 42% and 0.9 (rural). Only 2% of the 12-year-olds exhibited no calculus or gingival bleeding, while more than 70% had calculus. In conclusion, there is an urgent need for establishing caries-preventive activities for preschool children. The prevalence of caries among the 12-year-olds was not high, but their periodontal condition was unsatisfactory. Knowledge about gum bleeding and the use of fluoride was low. More oral health education activities should be organized, especially for the rural children.

Trinucleotide repeat analysis of Huntington's disease gene in Singapore

INTRODUCTION

Huntington's disease (HD) is an inherited neurodegenerative disorder characterised by chorea and progressive dementia. The mutation causing the disease has been identified as an unstable expansion of a trinucleotide (CAG)n. We have assessed the (CAG)n repeats in the patients and controls in our population.

MATERIALS AND METHODS

Polymerase chain reactions (PCRs) for the repeat region were carried out for 116 individuals: 10 were asymptomatic at-risk members from 5 families; 53 symptomatic patients from various hospitals; and 53 normal unrelated Singaporeans. Estimation of the number of repeats was based on Metaphor gel electrophoresis, sizing using the GeneScan on ABI 310 Genetic Analyzer, and sequencing using the same equipment.

RESULTS

Metaphor gel sizing generally gives an over-estimation, and GeneScan gives an under-estimation of repeat numbers compared with sequencing which is the gold standard. Of the 63 patients and family members tested, 25 had one expanded allele of 40 to 54 CAG repeats and the other allele in the normal range of 15 to 30 repeats. One patient had an allele in the intermediate range (38).

CONCLUSION

The range of CAG repeats in the normal and HD alleles in our population is similar to those reported elsewhere. An accurate sizing can only be obtained with sequencing. For allele sizes in the intermediate range (37-40), sequencing should be carried out to confirm the carrier status of a patient.

Correlation of the apparent diffusion coefficient and the creatine level in early ischemic stroke: a comparison of different patterns by magnetic resonance

It has been reported that reduction of the apparent diffusion coefficient (ADC) after stroke can persist for several days, after which the ADC increases gradually to an abnormally high level. We evaluated ADC values of stroke lesions and compared the results to the cellular density of the lesion by means of the creatine (Cre) level. This two-parameter estimation is of particular relevance in ascertaining the underlying cellular status. Lesion-to-contralateral ADC ratios (ADCn) were obtained based on diffusion-weighted echo-planar and fast spin-echo imaging. Single-voxel localized spectroscopy was used for quantification of cerebral metabolites in infarcted regions. Their levels were also compared to that in homotopic contralateral regions. Fifteen patients with ischemic stroke were examined at times ranging from 18-88 hours following the onset of symptoms. In the stroke lesion, there was a significant correlation between the ADC and the Cre level showing that the higher the cell density the lower the ADC value. For ADCn vs. the lesion Cre concentration and the lesion-to-contralateral Cre ratio (Cre(n)), the strengths of relationship were R2 = 0.70 and 0.58, respectively. It is concluded that ADC is a good reflection of cell density. Greatly lowered ADC values occur within the context of a stable cellularity. ADC and the Cre level have complementary roles in the characterization of stroke lesion with regard to the sequential stage.

Spinocerebellar ataxia in Singapore: predictive features of a positive DNA test?

Significant differences in frequency of the different spinocerebellar ataxia (SCA) subtypes have been described to occur in different populations. A 'blunderbuss' diagnostic DNA testing approach would entail unnecessary healthcare cost. In this study, we determine the prevalence of SCA subtypes and predictive features of a positive DNA test in consecutive clinically diagnosed SCA cases in Singapore. Twenty-one consecutive patients from 14 families were evaluated over a 3-year period. Thirteen patients (61.9%) from 6 families had a positive DNA test. Eleven of these (all ethnic Chinese) had SCA 3 (abnormal CAG size ranged from 61 to 71), and 2 ethnic Malays had SCA 2 (abnormal CAG size of 39). Clinical features which were highly predictive of a positive DNA SCA test in our population included presence of a positive family history, chorea and dystonia, muscle and tongue fasciculations, gaze-evoked nystagmus, and hypertonia. Our study draws attention to the observation that knowledge of relatively specific features of the most common SCA subtype in a local population can greatly enhance the practical accuracy of the choice of which SCA DNA test to order.

Induction of apoptosis in glioma cell lines by TRAIL/Apo-2l

TRAIL/Apo-2L, a novel cytokine, is a member of the tumor necrosis factor (TNF) family and serves as an extracellular signal triggering apoptosis. TRAIL/Apo-2L is capable of killing various transformed cells but not unstimulated primary T cells. In this study, five human glioma cells (U87, U118, U178, U563, and A172) were examined for their susceptibility to the apoptotic effects of TRAIL/Apo-2L. TRAIL/Apo-2L cDNA was isolated by RT-PCR, and recombinant TRAIL/Apo-2L protein was purified by the pMAL-c2 system (New England Biolabs, Beverly, MA). Exposure of A172 cells to bacterially expressed soluble TRAIL/Apo-2L fusion protein at a concentration of 1 microg/ml resulted in significant cell death over a 24-h period. Three experiments were performed to suggest that the TRAIL/Apo-2L killing was through the induction of apoptosis of A172 target cells. In addition, the expression of TRAIL/Apo-2L in different glioma cells was found to be variable, and TRAIL/Apo-2L-induced apoptosis was in a cell type-dependent manner. Some correlation between the susceptibility to TRAIL/Apo-2L and the expression level of one of its cognate receptors, DR4, was observed. In addition, cycloheximide worked synergistically with TRAIL/Apo-2L to induce apoptosis in glioma cells.

Pneumocystis carinii pneumonia in an immunocompetent infant with congenital cytomegalovirus infection

The case of a term infant with congenital cytomegalovirus (CMV) infection who developed Pneumocystis carinii pneumonia (PCP) at 4 months of age is reported. Our patient suffered from severe malnutrition and zinc deficiency secondary to necrotizing enterocolitis since the age of 2 months. There was no evidence of human immunodeficiency virus infection. Qualitative and quantitative in vitro leukocyte functions were also normal. This case highlights the fact that PCP can occur in apparently immunocompetent term infants. Malnourished infants with zinc deficiency or congenital CMV infection are at increased risk of developing PCP.

Intestinal obstruction and gastrointestinal bleeding due to systemic amyloidosis in a woman with occult plasma cell dyscrasia

A 60-year-old woman presented to our hospital with repeated vomiting. Upper gastrointestinal endoscopy revealed a 1 cm diameter ulcer with clean base on the roof of the gastric antrum. Histological examination of gastric biopsies revealed abundant amorphous eosinophilic deposits in the submucosa. Congo red stain for amyloid was positive. A barium follow-through study revealed a mass in the jejunum causing incomplete obstruction. Urine for Bence Jones protein was negative. Serum protein electrophoresis did not reveal any abnormal band and serum immunoelectrophoresis did not detect any monoclonal immunoglobulin. Bone marrow examination, however, revealed an increased proportion of plasma cells. Subsequent immunohistochemical staining demonstrated monoclonal lambda light chains in the marrow plasma cells, thereby confirming a plasma cell dyscrasia. Amyloidosis involving the gastrointestinal tract can produce a wide variety of non-specific symptoms and signs. A high index of suspicion is necessary to arrive at an early diagnosis. Management consists of supportive therapy for the gastrointestinal tract as well as treatment of the underlying condition.

X-linked adrenoleukodystrophy: spinocerebellar variant

The phenotypic variability in X-linked adrenoleukodystrophy (X-ALD) can be wide and varied. Rarely, it can present with clinical signs of spinocerebellar degeneration. There are very few reported cases of selective predominant white matter disease of the cerebellum in these patients. We report a patient with a rare variant of adult onset ALD who was previously diagnosed as spinocerebellar ataxia. He was a 24-year-old male who had delayed developmental milestones, developed signs of spinocerebellar degeneration (SCD) after 10 years of Addison's disease. Serial Magnetic Resonance Imaging (MRI), revealed cerebellar and pontine white matter disease but sparing the cerebral cortex and supratentorial white matter. His diagnosis of X-ALD was subsequently confirmed by the elevated serum very long chain fatty acids. This patient illustrates the unusual clinical presentation and imaging features of X-ALD and the importance of considering X-ALD in the clinical context of spinocerebellar degeneration. Early recognition of this rare variant would allow proper genetic counselling and institution of dietary therapy and/or bone marrow transplantation.

Geographic distribution of private dentists in Hong Kong in 1989 and 1998

More than 80% of the dentists in Hong Kong are in private practice and third party payment schemes are uncommon. Thus, most dentists have to work according to the rules of a free market and have to respond to the demands of the population. Using official data, it was found that the geographic distribution of private dentists was highly uneven. In 1989, the dentist to population ratio in the commercial districts was below 1:2,500 while in the new towns the ratio was larger than 1:20,000. There has been an improvement in the availability of dentists in the under-served areas during the past 10 years although there are still a considerable number of dentists practising in the areas on both sides of the Victoria Harbour.

Arresting dentine caries in Chinese preschool children

OBJECTIVES

To investigate the incidence of rehardening of caries lesions in children in Southern China taking part in a preventive programme.

DESIGN

Longitudinal study.

SAMPLE AND METHODS

A prevention programme was established for 168 3-6-year-old children in a kindergarten (KG1), which included regular oral health education sessions and a daily toothbrushing exercise using fluoridated toothpaste (1000 ppm F). A group of 121 children studying in two other kindergartens without a preventive programme formed the controls. Due to lack of resources and dental personnel, restorative and other curative treatments were not provided.

RESULTS

Rehardening of dentine caries (arrested caries) was found in children in both test and control groups. At the third annual examination, 45% of the caries lesions on the proximal surfaces of primary anterior teeth in KG1 children found at the baseline and previous annual examinations had become arrested. A multiple linear regression analysis indicated that baseline ds score and its interactions with the prevention programme, gender and the child's oral hygiene all had significant effect on the number of tooth surfaces with arrested caries at the third annual examination.

CONCLUSION

Results from this study support the use of simple prevention programmes to stabilize the caries situation in communities where intensive use of trained dental personnel is not feasible.

The 15-year outcome of Chinese patients with schizophrenia in Hong Kong

OBJECTIVE

To explore the differential outcome of schizophrenia in developed and developing countries. The 15-year outcome of patients with schizophrenia in Hong Kong is reported.

METHOD

In a 15-year retrospective outcome study, 100 patients with first-onset schizophrenia in 1977-1978 were randomly selected for outcome assessment from a pool of 797 patient files. The patterns of outcome were assessed by the same set of instruments and methodology as in other centres, since Hong Kong is 1 of the World Health Organization (WHO) centres for the International Study of Schizophrenia (ISoS).

RESULTS

Nineteen subjects were untraceable, and 10 subjects committed suicide. More than one-half of the subjects had a good symptomatic outcome, while about 20% of the subjects were rated as having a good psychosocial adjustment. Over the entire 15-year period, 96% of the subjects were maintained on medications, and 79% were living with family members.

CONCLUSION

Despite Hong Kong's developed economy, its schizophrenia outcome is similar to that in developing countries. The existence of good family support and active follow-up treatment may be important contributory factors to better outcome.

Prevention of early childhood caries--results of a fluoride toothpaste demonstration trial on Chinese preschool children after three years

OBJECTIVES

This field demonstration trial evaluates the long-term effects of introducing daily toothbrushing with fluoride toothpaste in a Chinese kindergarten (test group) compared to caries development in children who had no organized preventive program (control group).

METHODS

In the test group teacher-supervised toothbrushing was initiated with 1,000 ppm MFP toothpaste in addition to oral health education activities. Test and control children were examined at baseline (n = 289, aged 3 years) and annually thereafter.

RESULTS

After three years, 251 children (87%) were still in the trial. Caries development (dmfs) calculation included only those children who were present at both baseline and subsequent annual examinations. At baseline the mean dmfs was 4.8 in the test group and 6.5 in the control group (NS). After three years the caries increment was 6.2 and 8.4 in the test group and the control group, respectively (P < .05). Adjusting for reversals, the net caries increment was 3.6 and 6.3, respectively (P < .01). Additionally, multiple linear regression analysis indicated that both baseline dmfs, the program and plaque level had a significant effect on the net caries increment. The use of hierarchical caries severity zones was useful for the identification of those children most at risk for further caries development.

CONCLUSIONS

We conclude that a daily toothbrushing with limited involvement of professional staff was feasible in a Chinese kindergarten and that caries development was significantly slowed in the test children. Caries severity zones may possibly assist in determining levels of intervention.

Disordered water homeostasis in Asian patients with schizophrenia

OBJECTIVE

The aim of this study was to determine the prevalence of polydipsia-hyponatremia among patients with schizophrenia in an Asian mental hospital.

METHOD

Seven hundred and twenty-eight inpatients with schizophrenia were assessed for polydipsia-hyponatremia using case notes reviews, specific gravity of urine, normalised diurnal weight gain, and serum sodium levels.

RESULTS

One hundred and three (13.8%) patients had polydipsia, 30 (4.1%) had polydipsia-hyponatremia and 14 (1.9%) had a history of water intoxication. Eight of the 30 patients were receiving carbamazepine, three were on tricyclic antidepressants and two had diabetes mellitus and were on sulfonylureas.

CONCLUSION

The prevalence of water intoxication among polydipsic patients was low compared to Western studies. This could be due to different methods of assessing polyuria, or ethnic differences and/or the prohibition of smoking in our patients. Certain medications might have also contributed to hyponatremia.

Patterns of dental caries severity in Chinese kindergarten children

The dental caries status of a population group is traditionally described by mean values of decayed, missing and filled teeth or surfaces (DMFT or S). Because of the limitations of the DMF values alone, additional measures of dental caries become important. A system of describing the pattern of dental caries attack hierarchically according to severity of caries was suggested by Poulsen & Horowitz (Community Dent Oral Epidemiol 1974;2:7-11). The purpose of the present study was to analyze caries data from a group of 3-6-year-old Chinese kindergarten children according to this hierarchical system, assess the hierarchical assumptions of the system with deciduous teeth and evaluate its usefulness as an additional caries description for a kindergarten population. As part of a longitudinal field trial, baseline caries data were collected from 452 children. Caries was registered by tooth surface without the use of radiographs. Each child was assigned to one of six mutually exclusive zones of increasing caries severity, from zone 0=caries free through zone 5, the most severe, assuming that once a child was classified into a given zone it automatically belonged to all zones of lesser severity (except zone 0). On the basis of the original six zones, 61% of the children were classified correctly according to the hierarchical concept, but different alternative models which merged one or more zones together demonstrated varying percentages of correct classification, the cariologically most acceptable one placing 83% correctly. For each age group there was a close correlation between mean dmfs and increasing severity. The hierarchical model provides a valuable additional description of the caries status in deciduous teeth and is consistent with professional and epidemiological knowledge of caries attack patterns.

Therapeutic effects of supervised chlorhexidine mouthrinses on untreated gingivitis

AIM

The aim of the present study was to test the presumptive therapeutic effect of chlorhexidine digluconate in a population with untreated gingivitis and presence of abundant calculus. SETTING AND STUDY DESIGN: Sixty subjects (approximately mean age of 23.4) were recruited from a knitting factory in the Province of Guangdong, People's Republic of China. By applying a double-blind clinical trial design the participants were divided into two groups (Test and Control) and matched according to their mean GI scores. The Test group (n = 20) was assigned to two daily mouthrinses for 6 days per week using 0.12% chlorhexidine digluconate (Peridex). The Control group (n = 40) rinsed twice daily with a placebo solution. All the rinsings were supervised and timed for 45 s. No attempt was made to influence the oral hygiene habits of the participants. Prior to and after 3 months of the supervised rinsing, plaque was scored using the Plaque Index system (PII), and gingivitis was assessed using the criteria of the Gingival Index system (GI). Calculus was scored according to the Calculus Surface Severity Index system (CSSI), and stain was also graded by the Discoloration Index system (DI).

RESULTS

After 3 months, the Test group (n = 13) showed significant reduction in mean PII, GI and percentage of gingival bleeding (GB%), while significant increases in mean DI were observed. The improvement in gingival health was observed at all regions with marked reduction in mean GI (from GI = 1.40 to 1.08) and GB% reduction by 24-52%. The proportion of GI = 2 was also reduced significantly from 50-36%. The Control group (n = 23) also showed a decrease in mean PII but significant increases in the mean GI and GB%. Intergroup comparison showed statistically significant differences between mean GI, percentage of gingival bleeding (GB%) and mean DI for the test and control groups after 3 months of supervised rinsing. However, there were no significant intergroup differences for mean PII.

CONCLUSION

In conclusion, there was a significant effect of chlorhexidine on gingivitis, although the effect may be too limited to assure prognostic benefits in the prevention of future disease progression.

Idiopathic intracranial hypertension, empty sella turcica and polycystic ovary syndrome--a case report

Permanent visual loss is a well established major sequela of idiopathic intracranial hypertension (IIH). It is often insidious and frequently unnoticed by patients with IIH. It is vital to monitor these patients with serial perimetric and visual acuity tests because visual loss can be halted and occasionally reversed if treatment is begun early. We report a case of IIH with an empty sella turcica and polycystic ovary syndrome who developed visual field loss over ten years. This report illustrates the importance of close ophthalmic monitoring and detailed neurological and endocrinological evaluation to prevent complications in such patients.

Pilot study of high-dose thiotepa and etoposide with autologous bone marrow rescue in children and young adults with recurrent CNS tumors. The Children's Cancer Group

PURPOSE

This study was designed to determine the toxicity, radiographic response rate, and outcome following high-dose thiotepa, etoposide, and autologous bone marrow rescue (ABMR) for young patients with recurrent malignant brain tumors.

METHODS

Eligibility criteria required adequate renal, hepatic, and pulmonary function, and no bone marrow infiltration. Thiotepa 300 mg/m2 and etoposide 500 mg/ m2 were infused on 3 consecutive days, and autologous bone marrow was infused 72 hours following chemotherapy.

RESULTS

Forty-five patients with recurrent high-grade brain tumors, aged 8 months to 36 years (median, 8 years), were treated. Seven patients (16%) died of treatment-related toxicities within 56 days of marrow reinfusion. Delayed platelet engraftment occurred in 44% of patients who survived beyond day 56. Of 35 patients with radiographically measurable disease who survived at least 28 days following ABMR, there were two complete responses (CRs) and six partial responses (PRs), for an overall response (CRs plus PRs) rate of 23% (SE = 7%). Objective responses were observed in four of 14 assessable patients with high-grade glioma and in two of six with primitive neuroectodermal tumors (PNETs)/ medulloblastoma. Survival was significantly improved in patients treated with minimal residual disease (P < .0005). Five of 18 patients (28%) with high-grade gliomas remain free of disease at 39+, 44+, 49+, 52+, and 59+ months post-ABMR.

CONCLUSION

The combination of high-dose thiotepa and etoposide has activity against a variety of recurrent childhood brain tumors. These results merit further evaluation in children and young adults with both recurrent and newly diagnosed high-grade brain tumors.

Characterization of tachykinin receptors mediating plasma extravasation and vasodilatation in normal and acutely inflamed knee joints of the rat

1. Inflammatory actions of tachykinins in normal rat knee joints were compared with those of animals with acutely inflamed joints induced by intra-articular injection of 2% carrageenan. Plasma protein extravasation in rat knee joints, measured by protein micro-turbidimetry, was induced by intra-articular perfusion of selective tachykinin receptor agonists. Changes in joint blood flow, measured by laser Doppler perfusion imaging, were produced by topical applications of selective tachykinin receptor agonists to the joint capsule. 2. Carrageenan-injected rat knee joints showed significantly higher (P < 0.001) basal plasma extravasation (56 +/- 4 micrograms ml-1, n = 5) than normal rat knee joints (10 +/- 4 micrograms ml-1, n = 6). Intra-articular perfusion of the selective neurokinin1 (NK1) receptor agonist [Sar9, Met(O2)11]-substance P (0.8 nmol min-1) for 60 min elevated the basal plasma extravasation to 90 +/- 17 micrograms ml-1 (n = 6, P < 0.001) in normal joints, and to 150 +/- 14 micrograms ml-1 (n = 5, P < 0.001) in inflamed joints. Perfusion of the selective NK1 receptor antagonist N2-[(4R)-4-hydroxy-1-(1-methyl-1H- indol-3-yl)carbonyl-L-prolyl]-N-methyl-N-phenylmethyl-3-(2-naphthyl)- L-alaninamide (FK888; 0.8 nmol min-1) for 20 min followed by co-perfusion with the NK1 receptor agonist (0.8 nmol min-1) produced complete inhibition of the NK1 receptor agonist-induced plasma extravasation in the two groups of animals (for both groups; n = 3, P < 0.001). 3. Intra-articular perfusion of the selective NK receptor agonist [Nle10]-neurokinin A4-10 (0.8 nmol min-1) and the selective NK3 receptor agonist [MePhe7]-neurokinin B (0.8 nmol min1) produced no increase in plasma extravasation in normal or in inflamed rat knee joints (n = 4 and 11, P > 0.05). 4. Topical bolus applications of the NK1 receptor agonist [Sar9, Met(O2)11]-substance P onto normal joint capsules produced dose-dependent vasodilatation expressed as a voltage increase from control level. The maximum increase in blood flow was 2.05-0.21 V from a basal voltage of 3.42 +/- 0.07 V (n = 13, P < 0.001). To a much lesser extent, administration of the NK2 receptor agonist [Nle10]-neurokinin A4-10 also produced dose-dependent vasodilatation with maximum increase of 0.46 +/- 0.08 V from a basal level of 3.38 +/- 0.1 V (n = 7, P < 0.01). Animals with acutely inflamed joints showed enhanced vasodilator responses to the NK1 and NK2 receptor agonists (for both: P vs non-inflamed joints < 0.001). Thus, the NK1 and NK2 receptor agonists produced maximum increases of 2.56 +/- 0.19 V (basal level = 5.84 +/- 0.07 V; n = 7, P < 0.001) and 1.97 +/- 0.26 V (basal level = 6.31 +/- 0.23 V; n = 11, P < 0.001), respectively. The NK3 receptor agonist [MePhe7]-neurokinin B produced no change in blood flow in normal or in inflamed rat knee joints (n = 7 and 5, P > 0.05). 5. Bolus administration of the NK1 receptor antagonist FK888 (10 pmol) alone followed 5 min later by another dose of 10 pmol FK888 (i.e. total dose of 2 x 10 pmol) applied together with the NK1 receptor selective agonist [Sar9, Met(O2)11]-substance P produced partial, but significant inhibition of the NK1 receptor agonist-induced vasodilatation in both normal (maximum response reduced by 51.9 +/- 5.4%; n = 6, P < 0.001) and inflamed rat knee joints (maximum response reduced by 49.3 +/- 6.1%; n = 5, P < 0.001). The NK2 receptor agonist [Nle10]-neurokinin A4-10-induced vasodilator responses in inflamed joints were not affected by this treatment (n = 6, P > 0.05). However, with two higher doses of FK888 (both 1 nmol), the NK1 and the NK2 receptor agonist-induced vasodilator responses were abolished in the two groups of animals (n = 6-8, P < 0.005). 6. Administration of two doses of the selective NK2 receptor antagonist (S)-N-methyl-N-[4-acetylamino-4-phenylpiperidino)-2-(3,4-dichlorophenyl) -butyl]benzamide (SR48968;...

Modified barium swallow examination in dysphagic stroke patients

Aspiration in dysphagic stroke patients is common and causes significant morbidity and mortality. Bedside clinical assessment of aspiration risk is often unreliable, particularly in patients with silent aspiration. Twenty-five dysphagic stroke patients clinically assessed to have borderline risk of aspiration were studied using a Modified Barium Swallow (MBS) examination. MBS revealed definite aspiration of liquids in 6 patients (24%) and semisolids in 4 patients (16%). Combined clinical and MBS assessment revealed an additional 12 patients (48%) had problems swallowing liquids and 5 patients (20%) semisolids due to reasons other than aspiration. In total, oral feeding of liquids were contraindicated in 18 patients (72%) and semisolids in 9 patients (36%).

IN CONCLUSION

(1) In dysphagic stroke patients assessed clinically to have borderline risk of aspiration, MBS can distinguish those who aspirate from those who do not. MBS can also identify patients with other swallowing problems which expose them to potential aspiration. (2) Aspiration risk with food of various consistencies can be clearly defined, thus guiding the choice of food consistency and safe feeding methods.

Dental hygienists in Hong Kong: present and future status

PURPOSE

This study assessed the current employment status of dental hygienists practicing in Hong Kong, investigated factors affecting their employment, evaluated the satisfaction of local dental hygienists and their employers, and explored the career prospects of dental hygienists in Hong Kong.

METHODS

All registered dental hygienists (n = 64), all dentists who employed dental hygienists (n = 25), and a systematic sample of dentists who did not employ dental hygienists (n = 278) were surveyed in June 1994 concerning employment situation, salaries, job satisfaction, and opinions on future prospects for dental hygienists.

RESULTS

Response rates were 86% for dental hygienists (n = 55), 88% for employers (n = 22), and 63% for dentists at large (n = 175). Among the dental hygienists, 87% still were employed as dental hygienists, and both the dental hygienists and their employers agreed that the employment situation was satisfactory; however, several dental hygienists were considered to be working below their level of qualification. Major reasons for dentists not to employ a dental hygienist were having only one operatory and having an inadequate number of patients. In general, employers expressed satisfaction with the performance of the dental hygienists. Major reasons for employing a dental hygienist were that a dental hygienist would add professional and economical benefit to their clinic. Few dentists would support expanded duties for dental hygienists.

CONCLUSIONS

In Hong Kong, dental hygienists and their employers comprise a small group with limited impact on oral healthcare services. Dental hygienists' perceptions of their future roles and ambitions are higher than those of their employers. To further the development of dental services in Hong Kong and meet documented oral healthcare needs in the population, greater utilization of dental hygienists should be promoted.

Polyethylene glycol method is superior to ammonium sulfate and protein-A sepharose-4B method in fractionating thyroid stimulating immunoglobulin in Graves' disease

BACKGROUND

The purpose of this study is to compare the performance of three methods, i.e., ammonium sulfate, polyethylene glycol (PEG) and protein A sepharose 4B in fractionation of thyroid stimulating immunoglobulin.

METHODS

Twelve patients with Graves' disease and twelve age-, sex-matched normal controls were recruited. 0.9 ml of saturated ammonium sulfate was added slowly to 1.1 ml of sera of all subjects and was stirred until reaching 45% saturation. The precipitation was allowed to form at 4 degrees C overnight. The solution was centrifuged at 10,000 x g for 5 minutes. The precipitate was washed twice with 45% ammonium sulfate, dissolved in 0.55 ml of distilled water equal to half of the initial volume of the serum and dialyzed against 200 volumes of phosphate-buffered saline (PBS) for 48 hours. Another 0.5 ml of serum sample from the same patients was mixed with 1.5 ml of 20% polyethylene, followed by centrifugation at 2,800 g for 20 minutes. The pellet was dissolved in 0.6 ml of Hanks' medium without NaCl containing 1.5% bovine serum albumin, 20mM HEPES: 1 ml of sera was applied to 0.75 g of protein A sepharose-4B in PBS buffer and eluted with glycine, pH 2.3. By adding immunoglobulin (Ig) from the different methods to the FRTL-5 tissue culture, we determined the cAMP generation.

RESULTS

Patients with Graves' disease were found to have higher serum thyroxine and triiodothyronine concentrations (p < 0.001) and significantly higher free thyroxine concentration than normal subjects. Ig elicited stronger response in cyclic AMP generation when prepared with PEG method, as compared with the other two methods (p < 0.001). With sepharose-4B Ig preparation, 10 out 12 patients (83.33%) showed positive thyroid stimulating immunoglobulin (TSI) while with ammonium sulfate precipitation, nine out 12 patients (75%) showed positive TSI. On the other hand, all patients showed positive TSI with PEG precipitation. When the degree of thyrotoxicosis was classified in terms of thyroid hormone concentrations, there was no correlation between TSI titers and thyroid hormone concentration.

CONCLUSIONS

Polyethylene glycol is superior to both ammonium sulfate and protein A sepharose-4B in fractionating TSI in terms of sensitivity and convenience in operation.

Huntington's disease in five siblings

Huntington's disease is an autosomal dominant neurodegenerative condition which is rare in Singapore. Five siblings with progressive chorea and dementia were treated at the Singapore General Hospital and followed up over a seven-year period. Family history revealed five deceased affected individuals, two living affected siblings and more than 35 "at risk" offspring spanning another two generations each with about a 50% probability of carrying the Huntington's disease gene. We believe this is the largest kindred with Huntington's disease in Singapore.

Huntington's disease: recent progress in gene mapping and potential local application in Singapore

Advances in the field of molecular genetics have made testing of individuals for the presence of certain genes possible. Programmes for testing families with Huntington's disease have been developed overseas but not locally. We outline our beginning attempts to make services such as prenatal exclusion testing and presymptomatic carrier detection available to Singapore families with Huntington's disease.

Urgent therapy for stroke. Part II. Pilot study of tissue plasminogen activator administered 91-180 minutes from onset

BACKGROUND AND PURPOSE

Renewed interest in thrombolytic therapy as potential treatment for patients with acute ischemic stroke prompted a dose-escalation safety study of tissue plasminogen activator in patients with very early (less than or equal to 90 minutes; see Part I) neurological symptoms. To test whether this stringent entry window might be safely lengthened, a second study was organized to test tissue plasminogen activator in patients with symptoms of 91-180 minutes' duration before treatment.

METHODS

An open-label, dose-escalation design was chosen. Eligible patients had pretreatment head computerized tomographic scanning and treatment begun 91-180 minutes from stroke onset. End points examined included the incidence of symptomatic and asymptomatic intracranial hemorrhage, other bleeding, and clinical outcome at 2 hours, 24 hours, and 3 months after treatment.

RESULTS

Twenty patients were treated at three hospitals in 13 months. Three doses were tested: 0.6 mg/kg (n = 8), 0.85 mg/kg (n = 6), and 0.95 mg/kg (n = 6). Two patients, one each at the two highest doses, sustained fatal intracerebral hemorrhages. Three patients (15%) improved by greater than or equal to 4 points on the National Institutes of Health Stroke Scale by 24 hours.

CONCLUSIONS

These observations suggest that tissue plasminogen activator treatment of acute ischemic stroke 91-180 minutes from onset in doses of greater than or equal to 0.85 mg/kg is attended by a risk of intracerebral hemorrhage approximating 17% (range 3-44%, 95% confidence interval). The rate of early neurological improvement observed in this study was small but does not exclude an improvement over the natural history. Future study with placebo control subjects and stratification by time to treatment is indicated.

Occult epidural chloroma complicated by acute paraplegia following lumbar puncture

Acute paraplegia complicating lumbar puncture in a leukemic patient with an unsuspected epidural chloroma is described, including the postmortem findings. Lumbar puncture can precipitate irreversible injury to the spinal cord in the patient with an occult lesion causing subarachnoid block. This account, in addition to documenting this phenomenon, suggests a potential advantage to magnetic resonance imaging over myelography.

Seizures in human immunodeficiency virus infection

Among 630 patients with human immunodeficiency virus infection, 70 patients with new-onset seizures were studied. Generalized seizures occurred in 66 patients (94%): they occurred as the initial seizure in 56 patients (80%) and during follow-up in another 10 patients (14%). Partial seizures (18 patients), status epilepticus (10 patients), and recurrent seizures (38 patients) were also noted. Identified processes included cerebral toxoplasmosis in 11 patients, cerebral lymphoma in 8, metabolic derangement in 8, cryptococcal meningitis in 7, and vascular infarction in 4. In 32 patients (46%) seizures were not associated with identifiable brain lesions and were believed to result from human immunodeficiency virus cerebral infection. Phenytoin treatment was associated with adverse drug reactions in 16 of 62 patients who received it. Our results suggest that the majority of patients with human immunodeficiency virus and seizures do not have secondary focal brain lesions as the cause of the seizures and that human immunodeficiency virus infection alone can, and often does, cause seizures.

Cerebrovascular disease and stroke in women

There are many special conditions which may predispose women to have a higher risk of stroke. These conditions include pregnancy and the puerperium, exogenous estrogen use, cerebral vasculitis, mitral valve prolapse and migraine. Recognition that certain stroke syndromes are more likely to affect women may aid the clinician in determining the optimal management of cerebrovascular disease and stroke in women.

Syringomyelia with Arnold Chiari I malformation: a report of four cases

4 cases of syringomyelia with type I Arnold Chiari malformation was seen presenting mainly with dissociated sensory loss, weakness of hands and upper motor neurone signs in the lower limbs. The first patient improved with posterior fossa decompression. The second and fourth patient appeared not to have improved after surgery, and the third case refused operation. One patient showed cord atrophy on myelogram presumably due to a collapse of the syrinx. One of the patients was unusual in that the syrinx extended down to segment T11. Magnetic resonance imaging of the posterior fossa and the cervical cord, to date, is the most useful procedure for diagnosis.

Syndrome of cerebellar ataxia and hypogonadotrophic hypogonadism: evidence for pituitary gonadotrophin deficiency

Familial cerebellar ataxia with hypogonadotrophic hypogonadism is a rare condition. Two affected siblings in a sibship of three were studied and found to have low plasma gonadotrophin levels. No rise in gonadotrophin levels was demonstrable after repeated stimulation with LHRH. The pattern of TSH and prolactin responses to TRH stimulation suggest hypothalamic dysfunction. The results clearly identify the cause of hypogonadism to be due to a defect in production or release of gonadotrophins by the pituitary gland and suggest that hypogonadism is part of a greater endocrine disturbance involving both the hypothalamus and pituitary.