MRI brain scan study of minor physical anomalies to aid the early diagnosis of autism

Poster Sessionspublished_or_final_versionThe 27th International College of Neuropsychopharmacology Congress (CINP 2010), Hong Kong, China, 6-10 June 2010. In International Journal of Neuropsychopharmacology, 2010, v. 13, suppl. S1, p. 182, abstract no. P-14.03

Using illness scripts to teach clinical reasoning skills to medical students

Background and Objectives: Most medical students learn clinical reasoning skills informally during clinical rotations that have varying quality of supervision. We conducted a randomized controlled trial to determine if a workshop that uses "illness scripts" could improve students' clinical reasoning skills when making diagnoses of patients portrayed in written scenarios. Methods: In 2007-2008, 53 fourth-year medical students were randomly assigned to either a family medicine (intervention) or psychiatry (control) clerkship at The Chinese University of Hong Kong. Students in the intervention group participated in a 3-hour workshop on clinical reasoning that used illness scripts. The workshop was conducted with small-group teaching using a Web-based set of clinical reasoning problems, individualized feedback, and demonstration of tutors' reasoning aloud. The effectiveness of the intervention was assessed using the Diagnostic Thinking Inventory (DTI) and the measurement of individual students' performance in solving clinical reasoning problems (CRP). Results: The postintervention overall DTI scores between groups were similar (mean difference 0, 95% confidence interval [CI]= -7.4 to 7.4). However, the total scores on the CRP assessment were 14% (95% CI=8% to 21%) higher in the intervention group than in controls. Conclusion: A workshop on illness scripts may have some benefit for improving diagnostic performance in clinical reasoning problems.link_to_OA_fulltex

Increase in methicillin-resistant Staphylococcus aureus acquisition rate and change in pathogen pattern associated with an outbreak of severe acute respiratory syndrome

Background. An outbreak of severe acute respiratory syndrome (SARS) occurred in our 22-bed intensive care unit (ICU; Prince of Wales Hospital, Hong Kong, HKSAR, China) from 12 March to 31 May 2003, when only patients with SARS were admitted. This period was characterized by the upgrading of infection control precautions, which included the wearing of gloves and gowns all the time, an extensive use of steroids, and a change in antibiotic prescribing practices. The pattern of endemic pathogenic organisms, the rates of acquisition of methicillin-resistant Staphylococcus aureus (MRSA), and the rates of ventilator-associated pneumonia (VAP) were compared with those of the pre-SARS and post-SARS periods. Methods. Data on pathogenic isolates were obtained from the microbiology department (Prince of Wales Hospital). Data on MRSA acquisition and VAP rates were collected prospectively. MRSA screening was performed for all ICU patients. A case of MRSA carriage was defined as an instance in which MRSA was recovered from any site in a patient, and cases were classified as imported or ICU-acquired if the first MRSA isolate was recovered within 72 h of ICU admission or after 72 h in the ICU, respectively. Results. During the SARS period in the ICU, there was an increase in the rate of isolation of MRSA and Stenotrophomonas and Candida species but a disappearance of Pseudomonas and Klebsiella species. The MRSA acquisition rate was also increased: it was 3.53% (3.53 cases per 100 admissions) during the pre-SARS period, 25.30% during the SARS period, and 2.21% during the post-SARS period (P < .001). The VAP rate was high, at 36.5 episodes per 1000 ventilator-days, and 47% of episodes were caused by MRSA. Conclusions. A SARS outbreak in the ICU led to changes in the pathogen pattern and the MRSA acquisition rate. The data suggest that MRSA cross-transmission may be increased if gloves and gowns are worn all the time.published_or_final_versio

Hong Kong's domestic health spending—financial years 1989/90 through 2004/05

This report presents the latest estimates of Hong Kong’s domestic health spending between fiscal years 1989/90 and 2004/05, cross-stratified and categorised by financing source, provider and function on an annual basis. Total expenditure on health was HK$67 807 million in fiscal year 2004/05. In real erms, total expenditure on health showed positive growth averaging 7This increase was largely driven by the rise in public spending, which rose 9Of the$67 807 million total health expenditure in 2004/05, current xpenditure comprised $65 429 million (96$2378 million (4%) were apital expenses (ie investment in medical facilities). Services of curative care ccounted for the largest share of total health spending (67%) which were made p of ambulatory services (35%), in-patient curative care (28%), day patient ospital services (3%), and home care (1%). The next largest share of total health xpenditure was spent on medical goods outside the patient care setting (10%). Analysed by health care provider, hospitals accounted for the largest share (46%) and providers of ambulatory health care the second largest share (30%) f total health spending in 2004/05. We observed a system-wide trend towards ervice consolidation at institutions (as opposed to free-standing ambulatory linics, most of which are staffed by solo practitioner). In 2004/05, public expenditure on health amounted to $35 247 million (53.9$30 182 million) was mostly incurred at providers of mbulatory health care (54.6%). This reflects the mixed health care economy of ong Kong where public hospitals generally account for about 90% of total beddays nd private doctors (including Western and Chinese medicine practitioners) rovide 75% to 80% of out-patient care. While both public and private spending were mostly expended on personal ealth care services and goods (92.9%), the distributional patterns among functional ategories differed. Public expenditure was targeted at in-patient care (54.2%) and ubstantially less on out-patient care (24.5%), especially low-intensity first-contact are. In comparison, private spending was mostly concentrated on out-patient care (49.6%), whereas medical goods outside the patient care setting (22 .6%) and inpatient are (18.8%) comprised the majority of the remaining share. Compared to OECD countries, Hong Kong has devoted a relatively low percentage of gross domestic product to health in he last decade. As a share of total spending, public funding (either general government revenue or social security funds) was lso lower than in most comparably developed economies, although commensurate with its public revenue collection base.published_or_final_versio

Spectral Pattern Recognition by a Two-Layer Perceptron: Effects of Training Set Size

Pattern recognition in urban areas is one of the most challenging issues in classifying satellite remote sensing data. Parametric pixel-by-pixel classification algorithms tend to perform poorly in this context. This is because urban areas comprise a complex spatial assemblage of disparate land cover types - including built structures, numerous vegetation types, bare soil and water bodies. Thus, there is a need for more powerful spectral pattern recognition techniques, utilizing pixel-by-pixel spectral information as the basis for automated urban land cover detection. This paper adopts the multi-layer perceptron classifier suggested and implemented in [5]. The objective of this study is to analyse the performance and stability of this classifier - trained and tested for supervised classification (8 a priori given land use classes) of a Landsat-5 TM image (270 x 360 pixels) from the city of Vienna and its northern surroundings - along with varying the training data set in the single-training-site case. The performance is measured in terms of total classification, map user's and map producer's accuracies. In addition, the stability with initial parameter conditions, classification error matrices, and error curves are analysed in some detail. (authors' abstract)Series: Discussion Papers of the Institute for Economic Geography and GIScienc

A qualitative study of the views of patients with long-term conditions on family doctors in Hong Kong

&lt;b&gt;Background&lt;/b&gt; Primary care based management of long-term conditions (LTCs) is high on the international healthcare agenda, including the Asia-Pacific region. Hong Kong has a 'mixed economy' healthcare system with both public and private sectors with a range of types of primary care doctors. Recent Hong Kong Government policy aims to enhance the management of LTCs in primary care possibly based on a 'family doctor' model. Patients' views on this are not well documented and the aim of the present study was to explore the views of patients with LTCs on family doctors in Hong Kong.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Methods&lt;/b&gt; The views of patients (with a variety of LTCs) on family doctors in Hong Kong were explored. Two groups of participants were interviewed; a) those who considered themselves as having a family doctor, b) those who considered themselves as not having a family doctor (either with a regular primary care doctor but not a family doctor or with no regular primary care doctor). In-depth individual semi-structured interviews were carried out with 28 participants (10 with a family doctor, 10 with a regular doctor, and 8 with no regular doctor) and analysed using the constant comparative method.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Results&lt;/b&gt; Participants who did not have a family doctor were familiar with the concept but regarded it as a 'luxury item' for the rich within the private healthcare system. Those with a regular family doctor (all private) regarded having one as important to their and their family's health. Participants in both groups felt that as well as the more usual family medicine specialist or general practitioner, traditional Chinese medicine practitioners also had the potential to be family doctors. However most participants attended the public healthcare system for management of their LTCs whether they had a family doctor or not. Cost, perceived need, quality, trust, and choice were all barriers to the use of family doctors for the management of their LTCs.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Conclusions&lt;/b&gt; Important barriers to the adoption of a 'family doctor' model of management of LTCs exist in Hong Kong. Effective policy implementation seems unlikely unless these complex barriers are addressed

Bacteremic community-acquired pneumonia due to Klebsiella pneumoniae: Clinical and microbiological characteristics in Taiwan, 2001-2008

<p>Abstract</p> <p>Background</p> <p><it>Klebsiella pneumoniae </it>is the major cause of community-acquired pyogenic infections in Taiwan. This retrospective study evaluated the clinical and microbiological characteristics of bacteremic community-acquired pneumonia due to <it>K. pneumoniae </it>in Taiwanese adults.</p> <p>Methods</p> <p>The clinical characteristics of bacteremic community-acquired pneumonia (CAP) in adults due to <it>K. pneumoniae </it>were compared to those of adults with bacteremic CAP due to <it>Streptococcus pneumoniae </it>at a tertiary medical center in Taiwan from 2001-2008. Risk factors for mortality of bacteremic CAP due to <it>K. pneumoniae </it>were analyzed. All clinical isolates of <it>K. pneumoniae </it>were examined for capsular serotypes, hypermucoviscosity phenotype, aerobactin and <it>rmpA </it>gene.</p> <p>Results</p> <p><it>K. pneumoniae </it>was the dominant cause of bacteremic CAP and was associated with a more fulminant course and a worse prognosis than bacteremic CAP due to <it>Streptococcus pneumoniae</it>. Initial presentation with septic shock and respiratory failure were independent risk factors for both early and total mortality. Serotype K1 and K2 comprised around half of all isolates. There were no significant differences in the clinical characteristics of patients with bacteremic CAP due to K1/K2 and non-K1/K2 isolates. Hypermucoviscosity phenotype as well as the aerobactin and <it>rmpA </it>genes were highly prevalent in the <it>K. pneumoniae </it>isolates.</p> <p>Conclusions</p> <p><it>K. pneumoniae </it>continued to be the dominant cause of bacteremic CAP in Taiwanese adults during 2001-2008. Initial presentation with septic shock and respiratory failure were independent risk factors for both early and total mortality from <it>K. pneumoniae </it>bacteremic CAP. Serotypes K1/K2 comprised around half of all isolates, but did not predispose patients to a poor clinical outcome. Physicians should be aware of the poor prognosis of any patient with bacteremic <it>K. pneumoniae </it>CAP and monitor these patients more closely.</p

Control and Characterization of Individual Grains and Grain Boundaries in Graphene Grown by Chemical Vapor Deposition

The strong interest in graphene has motivated the scalable production of high quality graphene and graphene devices. Since large-scale graphene films synthesized to date are typically polycrystalline, it is important to characterize and control grain boundaries, generally believed to degrade graphene quality. Here we study single-crystal graphene grains synthesized by ambient CVD on polycrystalline Cu, and show how individual boundaries between coalescing grains affect graphene's electronic properties. The graphene grains show no definite epitaxial relationship with the Cu substrate, and can cross Cu grain boundaries. The edges of these grains are found to be predominantly parallel to zigzag directions. We show that grain boundaries give a significant Raman "D" peak, impede electrical transport, and induce prominent weak localization indicative of intervalley scattering in graphene. Finally, we demonstrate an approach using pre-patterned growth seeds to control graphene nucleation, opening a route towards scalable fabrication of single-crystal graphene devices without grain boundaries.Comment: New version with additional data. Accepted by Nature Material

MRI Study of Minor Physical Anomaly in Childhood Autism Implicates Aberrant Neurodevelopment in Infancy

Background: MPAs (minor physical anomalies) frequently occur in neurodevelopmental disorders because both face and brain are derived from neuroectoderm in the first trimester. Conventionally, MPAs are measured by evaluation of external appearance. Using MRI can help overcome inherent observer bias, facilitate multi-centre data acquisition, and explore how MPAs relate to brain dysmorphology in the same individual. Optical MPAs exhibit a tightly synchronized trajectory through fetal, postnatal and adult life. As head size enlarges with age, inter-orbital distance increases, and is mostly completed before age 3 years. We hypothesized that optical MPAs might afford a retrospective 'window' to early neurodevelopment; specifically, inter-orbital distance increase may represent a biomarker for early brain dysmaturation in autism. Methods: We recruited 91 children aged 7-16; 36 with an autism spectrum disorder and 55 age- and gender-matched typically developing controls. All children had normal IQ. Inter-orbital distance was measured on T1-weighted MRI scans. This value was entered into a voxel-by-voxel linear regression analysis with grey matter segmented from a bimodal MRI data-set. Age and total brain tissue volume were entered as covariates. Results: Intra-class coefficient for measurement of the inter-orbital distance was 0.95. Inter-orbital distance was significantly increased in the autism group (p = 0.03, 2-tailed). The autism group showed a significant relationship between inter-orbital distance grey matter volume of bilateral amygdalae extending to the unci and inferior temporal poles. Conclusions: Greater inter-orbital distance in the autism group compared with healthy controls is consistent with infant head size expansion in autism. Inter-orbital distance positively correlated with volume of medial temporal lobe structures, suggesting a link to "social brain" dysmorphology in the autism group. We suggest these data support the role of optical MPAs as a "fossil record" of early aberrant neurodevelopment, and potential biomarker for brain dysmaturation in autism. © 2011 Cheung et al.published_or_final_versio

A population-based nested case control study on recurrent pneumonias in children with severe generalized cerebral palsy: ethical considerations of the design and representativeness of the study sample

BACKGROUND: In children with severe generalized cerebral palsy, pneumonias are a major health issue. Malnutrition, dysphagia, gastro-oesophageal reflux, impaired respiratory function and constipation are hypothesized risk factors. Still, no data are available on the relative contribution of these possible risk factors in the described population. This paper describes the initiation of a study in 194 children with severe generalized cerebral palsy, on the prevalence and on the impact of these hypothesized risk factors of recurrent pneumonias. METHODS/DESIGN: A nested case-control design with 18 months follow-up was chosen. Dysphagia, respiratory function and constipation will be assessed at baseline, malnutrition and gastro-oesophageal reflux at the end of the follow-up. The study population consists of a representative population sample of children with severe generalized cerebral palsy. Inclusion was done through care-centres in a predefined geographical area and not through hospitals. All measurements will be done on-site which sets high demands on all measurements. If these demands were not met in "gold standard" methods, other methods were chosen. Although the inclusion period was prolonged, the desired sample size of 300 children was not met. With a consent rate of 33%, nearly 10% of all eligible children in The Netherlands are included (n = 194). The study population is subtly different from the non-participants with regard to severity of dysphagia and prevalence rates of pneumonias and gastro-oesophageal reflux. DISCUSSION: Ethical issues complicated the study design. Assessment of malnutrition and gastro-oesophageal reflux at baseline was considered unethical, since these conditions can be easily treated. Therefore, we postponed these diagnostics until the end of the follow-up. In order to include a representative sample, all eligible children in a predefined geographical area had to be contacted. To increase the consent rate, on-site measurements are of first choice, but timely inclusion is jeopardized. The initiation of this first study among children with severe neurological impairment led to specific, unexpected problems. Despite small differences between participants and non-participating children, our sample is as representative as can be expected from any population-based study and will provide important, new information to bring us further towards effective interventions to prevent pneumonias in this population