Potential role of fibroblast growth factor 21 in the deterioration of bone quality in impaired glucose tolerance.

PURPOSE: Findings on trabecular bone score (TBS), an index of bone quality, have been reported in prediabetes defined by impaired fasting glucose or HbA1c. Here, we assessed the bone mineral density (BMD) and TBS in prediabetes individuals with impaired glucose tolerance (IGT), and investigated the association of these bone parameters with serum levels of fibroblast growth factor 21 (FGF21), a hormone implicated in bone metabolism and with higher levels in IGT. METHODS: Chinese postmenopausal women aged 55-80 years, without diabetes, were recruited from the Hong Kong Cardiovascular Risk Factor Prevalence Study in 2016-2018. Normal glucose tolerance (NGT) was defined by fasting glucose < 5.6 mmol/L and 2-h plasma glucose (2hG) < 7.8 mmol/L, and IGT by 2hG 7.8-11 mmol/L. Serum levels of FGF21 and other bone metabolism regulators were measured. Insulin sensitivity was assessed by the Matsuda index. Independent determinants of TBS were evaluated using multivariable stepwise linear regression. RESULTS: 173 individuals with NGT and 73 with IGT were included. TBS was lower in those with IGT compared to those with NGT, while BMD was comparable. Individuals with IGT had significantly higher serum FGF21 levels, which in turn showed an independent inverse relationship with TBS, attenuated after inclusion of the Matsuda index. Serum FGF21 levels, however, did not correlate with BMD. CONCLUSION: Among Chinese postmenopausal women, bone quality was worse in IGT, despite comparable bone density. FGF21 levels showed a significant independent inverse relationship with TBS, partly attributed to insulin resistance. Whether FGF21 contributes to the impaired bone quality in IGT remains speculative.

Size, location, and multiplicity of ruptured intracranial aneurysms in the Hong Kong Chinese population with subarachnoid haemorrhage.

OBJECTIVE: To review the pattern of ruptured intracranial aneurysms in terms of size, location, and the prevalence of multiple aneurysms in the Hong Kong Chinese population with subarachnoid haemorrhage. DESIGN: Retrospective study. SETTING: Three public hospitals in Hong Kong. PATIENTS: A total of 267 Chinese patients with subarachnoid haemorrhage from ruptured intracranial aneurysms between July 1998 and June 2002 were reviewed retrospectively. RESULTS: The patients had a mean age of 59 (range, 13-96) years, with a female-to-male ratio of 2:1. Concerning the age at presentation, males presented with ruptured intracranial aneurysms at a younger age (P=0.001) than females. Ruptured aneurysms were more commonly located in the anterior than posterior circulation (84% vs 16%). The posterior communicating artery (26%) and anterior communicating artery (22%) were the most common sites of rupture. As a whole, 64% of the aneurysms had a size of 5 mm or less. The anterior communicating artery had a higher proportion with a size of 5 mm or less compared to other locations (P<0.05). In this cohort, the prevalence of multiple aneurysms was 17%. There was no significant difference in the prevalence of multiple aneurysms between men and women (P=0.30). In patients with multiple aneurysms, the sizes of ruptured aneurysms were greater than those of the largest unruptured aneurysms (P<0.001). When compared with the group with single aneurysms, patients with multiple aneurysms had a smaller proportion of small aneurysms, sized 5 mm or less (P<0.05). CONCLUSIONS: The pattern of ruptured intracranial aneurysms in the Hong Kong Chinese population was different from western and Japanese populations. Although the distribution of locations for ruptured aneurysms was similar, Hong Kong Chinese had a larger proportion of small aneurysms sized 5 mm or less. The prevalence of multiple aneurysms in Hong Kong is comparable to that in the Japanese population, but lower than that in the western populations.

Adsorption of bovine serum albumin on fused silica: Elucidation of protein-protein interactions by single-molecule fluorescence microscopy.

The adsorption of bovine serum albumin (BSA) on fused silica at pH 4.7 was studied at the single molecules level by total-internal-reflection fluorescence microscopy. This pH value was the isoelectric point of BSA. At low [BSA] of 20pM, protein molecules adsorbed as monomers. At intermediate [BSA] of 500pM, protein molecules adsorbed as clusters of about five monomers on average. Both monomers and clusters had adsorption rate coefficients of the order 10(-7)ms(-1) and desorption rate coefficients of about 2x10(-2)s(-1). The respective steady-state coverage was about 10x higher than that at neutral pH, presumably because of the more favorable BSA-silica electrostatics. At pH 4.7 and with [BSA] higher than 100nM, adsorption begot further adsorption to produce nonlinear isotherms. The coverage at 1microM BSA was 2.5x that of the linearly extrapolated coverage. This suggests that at pH 4.7, solute-adsorbate affinity was the dominant factor that explains the enhanced adsorption observed in ensemble measurements.

Magnetic resonance whole body imaging at 3 Tesla: feasibility and findings in a cohort of asymptomatic medical doctors.

OBJECTIVES: To evaluate the feasibility of whole body imaging using a 3 Tesla magnetic resonance scanner without a contrast agent, and to study the prevalence of abnormal findings among a cohort of asymptomatic doctors. DESIGN: Prospective study. SETTING: Private hospital, Hong Kong. PARTICIPANTS: A total of 132 asymptomatic medical doctors (111 men, 21 women), with a mean age of 56 (range, 38-82) years, volunteered for the study. They underwent corresponding whole body imaging at our hospital between October 2005 and February 2006. Imaging involved a 3 Tesla magnetic resonance scanner with 32 channels, parallel imaging, Total Imaging Matrix technology, a maximum gradient amplitude of 40 mT/m and a slew rate of 200 mT/m/ms (Magnetom Tim Trio, Siemens Medical Solution, Erlangen, Germany). The use of matrix coils enabled coverage of the whole body. No contrast agent was used. MAIN OUTCOME MEASURES: Detection of abnormalities in asymptomatic, apparently healthy adults. RESULTS: All examinations were completed successfully. The mean scan time per subject was 33 (standard deviation, 4) minutes. All subjects tolerated the examination well and overall imaging quality was satisfactory. A total of 124 (94%) subjects had positive findings, of whom 24 (18%) had further workup. Five (4%) subjects were found to have tumours, of which two (1.5%) were proven malignant. Our cancer detection rate was comparable to that of other reported whole body screening studies using contrast magnetic resonance imaging and positron emission tomography. CONCLUSION: We demonstrated the feasibility of performing whole body imaging in 30 minutes, using 32-channel magnetic resonance imaging at 3 Tesla without a contrast agent or any ionising radiation.

Refractory epilepsy in a Chinese population.

OBJECTIVES: To investigate the proportion of Chinese patients with intractable seizures and the risk factors leading to refractory epilepsy. METHODS: Consecutive patients over 14 years of age attending a Neurology clinic were evaluated. Patients with epilepsy were classified into two groups according to their seizure control: refractory or seizure-free. Epilepsy was classified as idiopathic as defined by age-related onset and typical electroclinical characteristics, symptomatic if secondary to a structural abnormality and cryptogenic if the cause was unknown. Age, sex, epilepsy syndrome classification, aetiology, presence of mental retardation and the number of drugs used were compared between patients with refractory epilepsy and those in remission. RESULTS: Among 260 adolescent and adult patients with a mean age of 34 years (range 15-79), complete seizure control was achieved in 157 (60%) cases. Multivariate binomial logistic regression analysis showed that patients with mesial temporal sclerosis (OR=7.6, 95% CI 3.53-16.4, p<0.01) and the presence of mental retardation (OR=9.39, 95% CI 3.98-22.12, p<0.01) were more likely to develop pharmacoresistant epilepsy. CONCLUSION: In adults the underlying aetiology is an important factor as to whether patients develop intractable seizures. Poor control was also associated with the presence of mesial temporal sclerosis and mental retardation.

Adsorption kinetics of bovine serum albumin on fused silica: population heterogeneities revealed by single-molecule fluorescence microscopy.

The adsorption of bovine serum albumin (BSA) on fused silica at neutral pH was investigated at the single-molecule level by total internal reflection fluorescence microscopy. Dye-labeled BSA molecules that adsorbed on the quartz surface lit up as discrete, fluorescent dots which eventually disappeared upon desorption. Movies of these events offered unprecedented details for kinetics modeling. The results suggested that 99.3% of the BSA was not sticky, and even if adsorbed, it would desorb in minutes. In contrast, the remaining 0.7% was not only sticky, but would anchor in due course. Such population heterogeneity, otherwise masked in ensemble measurements, sheds new light on our understanding of protein adsorption. The methodology is also generally applicable to the studies of macromolecules at interfaces.

Osteomyelitis with proliferative periostitis: an unusual case.

Chronic osteomyelitis with subperiosteal new bone formation results from periosteal reaction to chronic inflammatory/infectious stimulation. In the maxillofacial region, it has traditionally been termed Garrè's osteomyelitis with proliferative periostitis and more recently periostitis ossificans. The term Garrè's osteomyelitis has been regarded as a misnomer by many authors in the recent literature. The term chronic osteomyelitis with proliferative periostitis, although cumbersome, is considered to be the most accurate description of the pathology. It usually affects the mandible of young patients secondary to dental infection. Management involves removal of the source of infection and antibiotic treatment. We present an unusual case of chronic osteomyelitis with proliferative periostitis affecting the mandible of a 12-year-old patient. The source of infection was related to the developing lower left third molar, which had apparently no communication with the oral cavity.

Functional disabilities profile of chinese elderly people with Alzheimer's disease - a validation study on the chinese version of the disability assessment for dementia.

This study aimed to determine the validity and applicability of the Chinese version of the Disability Assessment for Dementia (CDAD) in the Chinese elderly population. The original English version was translated and modified to a 47-item scale to suit the societal and cultural background of the Chinese population. The CDAD was administered to 169 community-residing Chinese elderly people with Alzheimer's disease (AD) and demonstrated high internal consistency (Cronbach's alpha=0.91), excellent test-retest reliability (intraclass correlation, ICC=0.99) and excellent interrater reliability (ICC=0.98). The functional disabilities profile of the same sample was examined. The CDAD had a high negative correlation with the Global Deterioration Scale (GDS; Spearman's rho=-0.89, p<0.001). ANOVA and post hoc comparisons showed there were significant differences in the mean CDAD scores across different GDS stages. To study the construct validity, the CDAD was administered concurrently with several instruments. The Instrumental Activities of Daily Living subscore of the CDAD had a high correlation with the Instrumental Activities of Daily Living Scale (r=0.94,p<0.001), and the Activities of Daily Living subscore of the CDAD had a high correlation with the Modified Barthel Index (r=0.82, p<0.001). A moderate correlation (r=0.60, p<0.001) with the Cantonese version of the Mini Mental State Examination was also found. Analysis of the relationship with sociodemographic factors indicated that the CDAD was not correlated with gender and education, and that the correlation with age was low. The CDAD was shown to be a reliable and valid instrument in assessing the functional disabilities of community-residing elderly subjects with AD in the Chinese population.

Wilson's disease with depression and parkinsonism.

Wilson's disease (WD) is an autosomal recessive disorder with reduced biliary excretion of copper plus impaired formation of ceruloplasmin, leading to copper accumulation in the liver, brain, kidney, and cornea. Clinical manifestations include liver damage, psychiatric symptoms, and neurological features. We report a 35-year-old woman with a history of deranged liver functions who had severe depression several years later and eventually presented with parkinsonian features. The underlying diagnosis is WD and family screening revealed WD in 2 other siblings. She could not tolerate penicillamine because of fever and leucopenia. While taking trientine hydrochloride and zinc sulphate, her parkinsonism improved and her depression remained in remission. WD should be considered in patients with unexplained liver function derangement or psychiatric symptoms. Early diagnosis and initiation of specific treatment are crucial in minimising any further cerebral and hepatic damage as well as securing possible improvement in organ functions.

Bath-related headache.

Bath-related headache (BRH) is a rare primary headache syndrome. We present our experience over seven years and review all reported cases of BRH. Thirteen patients, including six from our group, are described. BRH occurred exclusively in middle-aged or elderly Oriental women (mean age 51 years, range 32-67. Hong Kong 6 cases, Taiwan 4 cases, Japan 3 cases). The typical presentation was a uniphasic cluster of severe headache recurrently triggered by bathing or other activities involving contact with water. Each attack lasted 30 min to 30 h. Onset was hyperacute, consistent with that of thunderclap headache. Reversible multisegmental cerebral vasoconstriction was found in two patients. No underlying secondary causes were identified. Response to acute treatment was generally unsatisfactory, but headache could be prevented by avoiding the specific trigger(s). BRH runs a self-limiting course; all patients remitted within three months after onset. Nimodipine may shorten the duration of illness.

Role of magnetic resonance imaging for preoperative evaluation of patients with refractory epilepsy.

OBJECTIVE: To investigate the magnetic resonance imaging characteristics of patients with refractory epilepsy and the relationship to progression to surgery. DESIGN: Prospective observational study. SETTING: University teaching hospital, Hong Kong. PATIENTS: Patients undergoing preoperative evaluation for epilepsy surgery. MAIN OUTCOME MEASURE: Cranial magnetic resonance imaging findings, correlation with electroencephalographic results, and percentage of patients who were considered suitable candidates for surgery. RESULTS: Structural abnormalities associated with refractory epilepsy in 100 consecutive patients were mesial temporal sclerosis (30%), neocortical sclerosis (23%), vascular malformation (7%), neuronal migration disorders (7%), and tumours (5%). Normal brain scans were found for 28% of patients. Fourteen of 30 (46%) patients with medial temporal lobe lesions at magnetic resonance imaging were suitable candidates for surgery compared with 8/42 (19%) patients with extrahippocampal lesions (odds ratio=3.7; 95% confidence interval, 1.3-10.6; P<0.012). CONCLUSION: Mesial temporal sclerosis was the most common pathology in patients with refractory epilepsy. At the Prince of Wales Hospital, for patients who have undergone a basic magnetic resonance imaging protocol and surface electroencephalography, the result of cranial magnetic resonance imaging is an important determinant for whether patients will undergo surgery.

Computed tomography evaluation in acute stroke: retrospective study.

OBJECTIVE: To determine the accuracy with which 'frontline' hospital doctors interpret computed tomography brain scans. DESIGN: Retrospective study. SETTING: University teaching hospital, Hong Kong. PARTICIPANTS: Medical and emergency room doctors. MAIN OUTCOME MEASURE: Accuracy in correctly identifying features of acute stroke on 18 computed tomography brain scans. RESULTS: Computed tomography brain scan images showing easily detectable haemorrhage and infarct were identified in 91% and 90% of scans, respectively; but difficult-to-interpret scans with subtle features of haemorrhage or infarct were only correctly identified in 46% and 45% of readings, respectively. More experienced doctors did not perform better than junior doctors (P=0.69; 95% confidence interval, -1.84 to 2.73) and the mean total score for doctors from the emergency department did not differ significantly from that of doctors from the medical department (P=0.57; 95% confidence interval, -2.98 to 1.67). CONCLUSION: Early signs of infarct and small bleeds on computed tomography brain scans are not well recognised by doctors, regardless of clinical exposure or seniority. Ineligible patients may be treated with thrombolytic therapy as a result of such computed tomography scan misinterpretation.

Dentascan in oral imaging.

In the past, dental disease and lesions involving the jaw were either evaluated by plain radiography or tomography. The advent of spiral computed tomography (CT) and DentaScan is changing the imaging trend. It is now not only used for pre-implant assessment but also in the diagnosis of lesions affecting the jaw. This pictorial review discusses the role of DentaScan in the various abnormalities that may affect the mandible and maxilla.