bluuebunny/crossref_metadata_2025 huggingface dataset:
A Review of Clinical Pathway Data of 1663 Total Knee Arthroplasties in a Tertiary Institution in Singapore
Authors: Xu GG , Sathappan SS , Jaipaul J , Chan Siew Pang , Lai Choon Hin
Published: February 2023

Introduction and Objectives: A total knee arthroplasty (TKA) clinical pathway database has been used in our institution since the year 2000. The primary aim of this study was to review the patient epidemiology, postoperative complications and factors influencing hospital length of stay following TKA. The clinical outcomes and cost-savings between elective and same day admissions for TKA patients were also reviewed.

Materials and Methods: The study cohort retrieved from the database comprised 1371 patients (1663 knees) who underwent total knee replacement over a 6-year time period. The following variables were reviewed: epidemiological data, admission data (elective admission [EA] versus same day admission [SDA]), hospital length of stay (LOS), and complication rates.

Results: The mean age of patients undergoing TKA is 65.2 years (range, 22 to 90). Osteoarthritis was the main surgical indication in 96% of the study cohort. Overall, there was a gradual decline in the hospital length of stay for the study cohort for the 6-year time period. The overall complication rate was 2% and the 3 most common complications were deep vein thrombosis, pulmonary embolism and urinary tract infection.

Conclusion: With an increasing elderly population there will be an annual increase in the number of TKAs. In our local population TKAs are performed primarily for the Chinese female in the 7th decade. The overall complication rate of TKA remains low with a mortality rate of <1%.

Key words: Complications, Epidemiology, Total knee arthroplasty
Anaerobic Culture of Diabetic Foot Infections: Organisms and Antimicrobial Susceptibilities
Authors: Ng Lily SY , Kwang Lee Ling , Yeow Susan CS , Tan Thean Yen
Published: February 2023

Introduction: The prevalence of diabetes mellitus is high in Singapore. Infections of the lower limb are significant causes of morbidity in this population. Although the aerobic bacteriology of these infections is well-documented, there is less data available on the anaerobic pathogens involved. This study sets out to describe the anaerobic bacteria associated with diabetic foot infections, and evaluates the susceptibility to 3 antimicrobials with anaerobic activity.

Materials and Methods: Anaerobic culture was performed on operative samples taken from diabetic foot infections. Organisms were identified through standard microbiological methods and commercial identification kits. Antimicrobial susceptibility testing to clindamycin, metronidazole and imipenem was performed by agar dilution.

Results: One hundred and two strains of strict anaerobic bacteria were isolated from 30 unique specimens. The predominant anaerobic isolates were Peptostreptococcus spp. (46%) and Bacteroides fragilis group (19%). Antibiotic resistance was detected for clindamycin (18%), metronidazole (1%) and imipenem (2%).

Conclusion: Multiple anaerobic species can be isolated from diabetic foot infections. A significant proportion of isolates are resistant to clindamycin, while resistance to imipenem and metronidazole remains low.

Key words: Anaerobe, Antibiotic resistance, Bacterial
Attitudes of First-year Medical Students in Singapore Towards Older People and Willingness to Consider a Career in Geriatric Medicine
Authors: Chua Melvin PW , Tan Chay Hoon , Merchant Reshma , Soiza Roy L
Published: February 2023

Introduction: Training of future physicians in the care of elderly patients will need to evolve in accordance with the exponential increase of elderly patients, but some may have preconceived attitudes affecting their management. This study determined medical students’ attitudes towards older people and their willingness to consider a career in Geriatric Medicine.

Materials and Methods: All 250 first-year medical students, prior to any formal clinical exposure at the National University of Singapore School of Medicine, were asked to participate voluntarily in the study based on the UCLA Geriatrics Attitudes Scale. The 14-item questionnaire consisted of a mixture of positively and negatively worded questions answered on a 5-point Likert scale. A fifteenth question enquired about their willingness to consider Geriatric Medicine as a potential career choice.

Results: The mean UCLA attitudes score was 3.58 [±standard deviation (SD), 0.41] suggesting a generally positive attitude. There was a strong association between attitude scores and willingness to consider Geriatric Medicine as a career (R = 0.48, P <001). However, only one third of the cohort was willing to consider a career in Geriatric Medicine. There was no difference in attitude scores between male and female students, but females were significantly more likely to consider Geriatric Medicine as a potential career choice.

Conclusion: First-year medical students in Singapore have a generally positive attitude towards older people, although only 1 in 3 persons was willing to consider a career in Geriatric Medicine. Higher attitude scores and female gender were the main predictors of willingness to consider a career in Geriatric Medicine.

Key words: Attitudes, Career, Education, Medical students, Older people
Supporting Learners who are Studying or Training Using a Second Language: Preventing Problems and Maximising Potential
Authors: Mohanna Kay
Published: February 2023

Introduction: This paper looks at the barriers to effective postgraduate study potentially experienced by learners in the United Kingdom if their first language is not English. As part of the internationalisation of higher education, we are seeing a welcome increase in students leaving their home country to study. This brings benefits to both home and visiting students as they learn more about each other and come to understand differences and build on aspects they have in common. However it also brings specific challenges of linguistic capability, differences in cultural expectations of the role of learners and teachers and in the understanding of the nature of postgraduate study. English medium higher education institutions worldwide are increasingly engaged in development of courses on English for academic purposes, or for academic writing. There is even a Journal of English for Academic Purposes, with co-editors from Hong Kong and the UK. Previous research has tended to concentrate on teacher-centred issues such as maintaining the integrity of assessments (including a focus on inadvertent plagiarism), practical aspects such as familiarity and expertise with information technology and more recently an understanding that acculturation has a part to play in maximising the success of students moving from one country’s academic model to another.

Materials and Methods: This was a qualitative project during which students whose first language was not English were interviewed. Thirteen postgraduate students on a masters award in medical education were engaged in semi structured interviews to elicit their experiences, views and suggestions.
Results: Three themes emerged as important to the students in this study: understanding and being understood is not just due to the words we use; the nature of postgraduate study is not universal; and the need to maintain personal identity.

Key words: International students, Postgraduate study, Study skills
Quality Management of Medical Education at the Carl Gustav Carus Faculty of Medicine, University of Technology Dresden, Germany
Authors: Dieter Peter Erich
Published: February 2023

The Carl Gustav Carus Faculty of Medicine, University of Technology Dresden, Germany, was founded in 1993 after the reunification of Germany. In 1999, a reform process of medical education was started together with Harvard Medical International. The traditional teacherand discipline-centred curriculum was replaced by a student-centred, interdisciplinary and integrative curriculum which has been named DIPOL® (Dresden Integrative Patient/ProblemOriented Learning). The reform process was accompanied and supported by a parallel-ongoing Faculty Development Program. In 2004, a Quality Management Program in medical education was implemented, and in 2005 medical education received DIN EN ISO 9001:2000 certification. Quality Management Program and DIN EN ISO 9001:2000 certification were/are unique for the
34 medical schools in Germany. The students played a very important strategic role in all processes. They were/are members in all committees like the Faculty Board, the Board of Study Affairs (with equal representation) and the ongoing audits in the Quality Management Program. Students are the only ones who experience all years of the curriculum and are capable of detecting, for example gaps, overlaps, inconsistencies of the curriculum and assessments. Therefore, the in-depth knowledge of students about the medical school’s curriculum is a very helpful and essential tool in curriculum reform processes and Quality Management Programs of medical education. The reform in medical education, the establishment of the Quality Management program and the certification resulted in an improvement of quality and output of medical education and medical research.

Key words: Certification, Faculty development, Quality management
Assessment of Psychometric Properties of a Modified PHEEM Questionnaire
Authors: Gooneratne IK , Munasinghe SR , Siriwardena C , Olupeliyawa AM , Karunathilake I
Published: February 2023

Background: An effective tool in analysing the learning environment, customised to the Sri Lankan setting, is vital for the assessment and delivery of quality healthcare training of preregistration house officers. Such a tool should be reliable and valid. We assessed psychometric properties such as internal reliability and construct validity of a modified version of the Postgraduate Hospital Educational Environment Measure (PHEEM).

Materials and Methods: A modified PHEEM questionnaire customised to the Sri Lankan context was developed in accordance to the Sri Lanka Medical Council guidelines. The questionnaire was distributed to all interns at the National Hospital of Sri Lanka, Colombo North Teaching Hospital and Wathupitiwala Base Hospital during a calendar year (n = 100, response rate = 86%). Internal reliability and construct validity of the inventory were assessed by using Cronbach’s alpha and exploratory factor analysis respectively as statistical methods.

Results: PHEEM consists of 3 subscales: perceptions of autonomy, social support and teaching, which are factors perceived to be influencing the educational environment. This administration demonstrated high internal reliability as reflected by a Cronbach’s alpha value of 0.84. Exploratory factor analysis identified 12 factors with eigenvalue >1. However, the first factor had an eigenvalue of 6.7 (accounting for 19.7% of variance), while the rest had eigenvalues < 2.5. These results suggest a single predictive factor and thus a one-dimensional scale as opposed to the three-dimensional scale which is used in the current questionnaire.

Conclusions: The psychometric properties of this tool reflect a high degree of internal reliability in assessing the educational environment of intern doctors in Sri Lanka. It is possible that the clinical educational environment is collectively represented as a single dimension. This may be due to the complex interplay between individual items in the questionnaire. Therefore the psychometric properties do not justify the interpretation of the educational environment through specified subscales.

Key words: Clinical training, Learning environment, Psychometric analysis
Dehydration Rates and Rehydration Efficacy of Water and Sports Drink During One Hour of Moderate Intensity Exercise in Well-trained Flatwater Kayakers
Authors: Sun Jeremy MF , Chia Jason KK , Aziz Abdul Rashid , Tan Benedict
Published: February 2023

Introduction: The aim of this study is to investigate the amount of water loss and percentage dehydration experienced during 1 hour of paddling on the kayak ergometer so as to help coaches and athletes tailor a suitable and adequate rehydration regime. Also, rehydration efficacy between water and a well established, commercially available sports drink (Gatorade, Quaker Oats company, USA) was investigated in this cross-over study.

Materials and Methods: Ten national flatwater kayakers were monitored in a controlled setting while paddling the kayak ergometer for 1 hour at an intensity sustainable for long distance marathon. They rehydrated themselves ad libitum with provided beverage. Post-void towel-dried body mass was measured before and after the exercise with percentage dehydration calculated. Body core temperature (tympanic temperatures), ratings of perceived exertion and thirst index were monitored every 15 minutes. The amount of fluid consumed, urine output and urine specific gravity were obtained after exercise.
Results: The results [mean ± standard deviation (SD)] showed that kayakers underwent 1.10 ± 0.52% dehydration while rehydrating with water as compared to 0.72 ± 0.38% while rehydrating with Gatorade. Also, athletes on water rehydration had higher rating of perceived exertion (RPE) at the 30th and 60th minute mark of the exercise. Overall, athletes undergoing water rehydration lost significantly more body mass (0.70 ± 0.39 kg) as compared to rehydrating with Gatorade (0.46 ± 0.27).
Conclusion: Although the hydration efficacy of Gatorade proved superior to that of water, the athletes’ hydration habits with either fluids did not provide adequate hydration. It is recommended that specific strategies be developed to address dehydration and rehydration issues of kayakers in Singapore.

Key words: Canoe, Gatorade, Fluid replacement, Marathon
Human Thermoregulation and Measurement of Body Temperature in Exercise and Clinical Settings
Authors: Lim Chin Leong , Byrne Chris , Lee Jason KW
Published: February 2023

This review discusses human thermoregulation during exercise and the measurement of body temperature in clinical and exercise settings. The thermoregulatory mechanisms play important roles in maintaining physiological homeostasis during rest and physical exercise. Physical exertion poses a challenge to thermoregulation by causing a substantial increase in metabolic heat production. However, within a non-thermolytic range, the thermoregulatory mechanisms are capable of adapting to sustain physiological functions under these conditions. The central nervous system may also rely on hyperthermia to protect the body from “overheating.” Hyperthermia may serve as a self-limiting signal that triggers central inhibition of exercise performance when a temperature threshold is achieved. Exposure to sub-lethal heat stress may also confer tolerance against higher doses of heat stress by inducing the production of heat shock proteins, which protect cells against the thermolytic effects of heat. Advances in body temperature measurement also contribute to research in thermoregulation. Current evidence supports the use of oral temperature measurement in the clinical setting, although it may not be as convenient as tympanic temperature measurement using the infrared temperature scanner. Rectal and oesophagus temperatures are widely accepted surrogate measurements of core temperature (Tc), but they cause discomfort and are less likely to be accepted by users. Gastrointestinal temperature measurement using the ingestible temperature sensor provides an acceptable level of accuracy as a surrogate measure of Tc without causing discomfort to the user. This form of Tc measurement also allows Tc to be measured continuously in the field and has gained wider acceptance in the last decade.

Key words: Core temperature, Gastrointestinal temperature, Ingestible temperature sensor, Thermoregulation
Validation of Transcranial Doppler with CT Angiography in Cerebral Ischaemia: A Preliminary Pilot Study in Singapore
Authors: Rathakrishnan Rahul , Berne Yeh I , Quek Keng K , Hong Chiew S , Ong Benjamin KC , Chan Bernard PL , Sharma Vijay K
Published: February 2023

Introduction: Transcranial Doppler (TCD) is an established tool for the non-invasive assessment of cerebral blood flow. Since TCD results vary with the skills and experience of the sonographer, it requires validation against contrast angiography. We evaluated the diagnostic accuracy of TCD against computed tomography angiography (CTA) and the feasibility of the latter as an additional screening tool in our acute ischaemic stroke patients.

Materials and Methods: Our stroke unit manages about 700 patients annually. Acute stroke patients undergo TCD for vascular assessment of major arteries of the circle of Willis. Randomly selected acute stroke patients with significant stenosis on TCD underwent high-resolution cranial CTA with multidetector helical scanner. CTA was performed within 24 hours of TCD and images were interpreted by a neuroradiologist blinded to TCD findings. An independent neurosonologist re-evaluated TCD if CTA findings were contradictory. Additional information by either modality was also noted.
Results: Fifteen patients (12 men, mean age 61 ± 15years) with cerebral ischaemia and moderate (>50%) stenosis in ≥1 large intracranial arterial segment on routine TCD were evaluated by CTA. Compared with 21 segments of significant stenosis on CTA, TCD showed 16 true-positive, 3 false-positive and 5 false-negative results (sensitivity: 76.2%, positive predictive value: 84.2%). In 3 cases, TCD showed findings complementary to CTA (real-time embolisation, collateral flow patterns, evidence of distal M2 branch occlusion).
Conclusion: TCD in our neurovascular laboratory shows a satisfactory agreement with cranial CTA in evaluating patients with cerebral ischaemia. TCD can provide additional real-time dynamic findings complementary to information provided by CTA.

Key words: Cerebral ischaemia, CT angiography, Transcranial Doppler
Biomarkers of Mild Cognitive Impairment and Alzheimer’s Disease
Authors: Tang Bor Luen , Kumar Rajeev
Published: February 2023

Alzheimer’s disease (AD) is currently diagnosed only via clinical assessments and confirmed by postmortem brain pathology. Biochemical and neuroimaging markers could facilitate diagnosis, predict AD progression from a pre-AD state of mild cognitive impairment (MCI), and be used to monitor efficacies of disease-modifying therapies. It is now clear that cerebrospinal fluid (CSF) levels of Aβ40, Aβ42, total tau and phosphorylated tau have diagnostic values in AD. Measurements of the above CSF markers in combination are useful in predicting the risk of progression from MCI to AD. Recent advances further support a notion that plasma Aβ levels, expressed as an Aβ42/Aβ40 ratio, could also be of value. New potential biomarkers are emerging, and CSF or plasma marker profiles may eventually become part of the clinician’s toolkit for accurate AD diagnosis and management. These biomarkers, along with clinical assessment, neuropsychological testing and neuroimaging could achieve a much higher diagnostic accuracy for AD and related disorders in the future.

Key words: Alzheimer’s disease, b-amyloid (Ab), Biomarkers, Mild cognitive impairment (MCI), Tau
Corticospinal Tract Degeneration in Amyotrophic Lateral Sclerosis: A Diffusion Tensor Imaging and Fibre Tractography Study
Authors: Yin Hong , Cheng Sandy HT , Zhang Jian , Ma Lin , Gao Yuangui , Li Dejun , Lim CC Tchoyoson
Published: February 2023

Introduction: Motor neuron damage and cortical spinal tract (CST) degeneration in amyotrophic lateral sclerosis (ALS) are difficult to visualise and quantify on conventional magnetic resonance imaging (MRI).

Clinical Picture: We studied 8 ALS patients and 12 normal volunteers using diffusion tensor imaging (DTI) and fibre tractography using fibre assignment by continuous tracking (FACT) to study the fibres of the CST and the posterior thalamic radiation (PTR), a non-motor tract.
Outcome: Fibre tractography was successfully performed in all normal volunteers and all patients except 1. The fibre bundles of the CST, but not the PTR, were significantly reduced (P<0.05) in patients compared to normal volunteers.
Conclusion: Fibre tractography can visualise axonal degeneration in the CST and may provide supplementary information about upper motor neuron disease in ALS patients.

Key words: Amyltrophic lateral sclerosis, Diffusion-weighted imaging, Echo planar imaging, Fibre tractography, Magnetic resonance imaging
Translating the Family Medicine Vision into Educational Programmes in Singapore
Authors: Wong Teck Yee , Cheong Seng Kwing , Koh Gerald CH , Goh Lee Gan
Published: February 2023

The core of the Family Medicine (FM) vision is patient-centred care, requiring specific education and vocational training. We traced how FM education started and what have been achieved. FM training began in 1971 with the formation of the College of General Practitioners Singapore. Previously, training consisted of self-directed learning, lunchtime talks and examination preparation courses run by hospital specialists. Formal FM vocational training programmes in the United Kingdom and Australia provided the model for a 3-year programme in 1988. The tripartite relationship between the local university, College of Family Physicians and Ministry of Health, together with a structured training programme, contributed to its success. To date, more than 240 Family Physicians in Singapore have been awarded the Masters in Medicine (FM) degree. The Graduate Diploma in Family Medicine programme (GDFM) was introduced in 2000 for Family Physicians who wished to practice at an enhanced level. This programme has trained 194 doctors since then. Behind the scenes, the following were important developments: counterculture with a difference, tripartite stake-holding, training the trainers and learning from others. For the FM undergraduate programme, our aim is to develop the knowledge base, core values and roles of the Family Physician. Sustaining the value of Family Medicine as a career choice is the enduring vision.

Key words: Development, History, Medical education
A Cross-sectional Study of Primary-care Physicians in Singapore on Their Concerns and Preparedness for an Avian Influenza Outbreak
Authors: Wong Teck Yee , Koh Gerald CH , Cheong Seng Kwing , Sundram Meena , Koh Kelvin , Chia Sin Eng , Koh David
Published: February 2023

Introduction: During an avian influenza (AI) pandemic, primary-care physicians (PCPs) are expected to play key roles in the prevention and control of the disease. Different groups of PCPs could have different concerns and preparedness level. We assessed the concerns, perceived impact and preparedness for an outbreak among PCPs in Singapore. Materials and Methods: A cross-sectional survey of PCPs working in private practice (n = 200) and public clinics (n = 205) from March to June 2006 with an anonymous self-administered questionnaire on concerns (12- items), perceived impact (10 items) and preparedness (10 items) for an outbreak. Results: Two hundred and eighty-five PCPs responded – 149 (response rate: 72.7%) public and 136 (response rate: 67.3%) private. The majority were concerned about risk to their health from their occupation (95.0%) and falling ill with AI (89.7%). Most (82.5%) accepted the risk and only 33 (11.8%) would consider stopping work. For perceived impact, most felt that people would avoid them (69.6%) and their families (54.1%). The majority (81.3%) expected an increased workload and feeling more stressed at work (86.9%). For preparedness, 78.7% felt personally prepared for an outbreak. Public PCPs were more likely to be involved in infection-control activities and felt that their workplaces were prepared. Conclusions: Most PCPs felt personally prepared for an outbreak but were concerned about their exposure to AI and falling ill. Other concerns included social ostracism for themselves and their families. Public PCPs appeared to have a higher level of preparation. Addressing concerns and improving level of preparedness are crucial to strengthen the primary-care response for any AI outbreak. Key words: Impact, Bird flu, Planning, Response
Towards Mutual Trust, Transparency and Equity in Virus Sharing Mechanism: The Avian Influenza Case of Indonesia
Authors: Sedyaningsih Endang R , Isfandari Siti , Soendoro Triono , Supari Siti Fadilah
Published: February 2023

Introduction: As the country hardest hit by avian influenza, both in poultry and in human, Indonesia’s decision to withhold samples of avian influenza virus A (H5N1) has fired up a global controversy. The objective of this paper is to describe the position taken by Indonesia in the events leading to the decision and in those conducted to resolve the situation.

Methods: The sources for this paper are the Indonesian human influenza A(H5N1) case reports and study results, summaries, minutes and reports of national and international meetings of virus sharing, and other related Indonesian and WHO documents.
Results: The International Health Regulations 2005 have been applied in different ways based on different interpretations. While one party insists on the importance of free, non-conditional, virus sharing for risk assessment and risk response, Indonesia – as supported by most of the developing countries – stresses on the more basic principles such as sovereignty of a country over its biological materials, transparency of the global system, and equity between developed and developing nations.
Conclusions: This event demonstrates the unresolved imbalance between the affluent high-tech countries and the poor agriculture-based countries. Regional, global and in-country meetings must continue to be conducted to find solutions acceptable to all.

Key words: H5N1, IHR 2005, MTA, Sovereignty
Avian Influenza and Pandemic Influenza Preparedness in Hong Kong
Authors: Lam Ping Yan
Published: February 2023

Avian influenza A H5N1 continues to be a major threat to global public health as it is a likely candidate for the next influenza pandemic. To protect public health and avert potential disruption to the economy, the Hong Kong Special Administrative Region Government has committed substantial effort in preparedness for avian and pandemic influenza. Public health infrastructures for emerging infectious diseases have been developed to enhance command, control and coordination of emergency response. Strategies against avian and pandemic influenza are formulated to reduce opportunities for human infection, detect pandemic influenza timely, and enhance emergency preparedness and response capacity. Key components of the pandemic response include strengthening disease surveillance systems, updating legislation on infectious disease prevention and control, enhancing traveller health measures, building surge capacity, maintaining adequate pharmaceutical stockpiles, and ensuring business continuity during crisis. Challenges from avian and pandemic influenza are not to be underestimated. Implementing quarantine and social distancing measures to contain or mitigate the spread of pandemic influenza is problematic in a highly urbanised city like Hong Kong as they involved complex operational and ethical issues. Sustaining effective risk communication campaigns during inter-pandemic times is another challenge. Being a member of the global village, Hong Kong is committed to contributing its share of efforts and collaborating with health authorities internationally in combating our common public health enemy.

Key words: Emergency response, Infections, Surveillance, Quarantine
Preparing for an Influenza Pandemic in Singapore
Authors: Cutter Jeffery
Published: February 2023

The national strategy against pandemic influenza essentially consists of 3 prongs: (i) effective surveillance, (ii) mitigation of the pandemic’s impact, and (iii) render the population immune through vaccination. When the pandemic hits Singapore, the response plan aims to achieve the following 3 outcomes: (i) maintenance of essential services to limit social and economic disruption, (ii) reduction of morbidity and mortality through antiviral treatment, and (iii) slow and limit the spread of influenza to reduce the surge on healthcare services. The biggest challenge will come from managing the surge of demand on healthcare services. A high level of preparedness will help healthcare services better cope with the surge. Key words: Essential services, Healthcare, National preparedness, Non-pharmaceutical measures
Prevention and Control of Avian Influenza in Singapore
Authors: Leong Hon Keong , Goh Cheryl S , Chew Siang Thai , Lim Chee Wee , Lin Yueh Nuo , Chang Siow Foong , Yap Him Hoo , Chua Sin Bin
Published: February 2023

The highly pathogenic avian influenza (HPAI) H5N1 virus was first detected in 1996 in Guangdong, China. Since 2003, H5N1 outbreaks have been reported in parts of Asia, Europe, the Middle East, and Africa. It is currently entrenched among poultry in parts of Asia and poses a major challenge to animal and human health. Singapore is free from HPAI. Given Singapore’s need to import food, the Agri-Food and Veterinary Authority (AVA) has adopted a pro-active risk management system to prevent the introduction of HPAI. AVA’s approach maybe described as a multi-layered control strategy for the prevention and control of HPAI. The strategy includes control measures at source, border control measures, local control measures and emergency preparedness.

Key words: Biosecurity, DFZ, H5N1, HPAI
Vaccines for Pandemic Influenza. The History of our Current Vaccines, their Limitations and the Requirements to Deal with a Pandemic Threat
Authors: Hampson Alan W
Published: February 2023

Fears of a potential pandemic due to A(H5N1) viruses have focussed new attention on our current vaccines, their shortcomings, and concerns regarding global vaccine supply in a pandemic. The bulk of current vaccines are inactivated split virus vaccines produced from egggrown virus and have only modest improvements compared with those first introduced over 60 years ago. Splitting, which was introduced some years ago to reduce reactogenicity, also reduces the immunogenicity of vaccines in immunologically naïve recipients. The A(H5N1) viruses have been found poorly immunogenic and present other challenges for vaccine producers which further exacerbate an already limited global production capacity. There have been some recent improvements in vaccine production methods and improvements to immunogenicity by the development of new adjuvants, however, these still fall short of providing timely supplies of vaccine for all in the face of a pandemic. New approaches to influenza vaccines which might fulfil the demands of a pandemic situation are under evaluation, however, these remain some distance from clinical reality and face significant regulatory hurdles.

Key words: Adjuvant, Antigen, Cell-culture, Immune response, Immunogenicity, Influenza A(H5N1), Split vaccine
Autologous Bone Marrow Plasma Injection after Arthroscopic Debridement for Elbow Tendinosis
Authors: Moon Young Lae , Jo Sueng-Hwan , Song Chang Hun , Park Geon , Lee Hyun Ju , Jang Soo Jeong
Published: February 2023

Introduction: The treatment of tendinosis of elbow can be challenging, yet rewarding. Nevertheless, for the patients who failed conservative management and develop persistent recalcitrant symptoms, surgical intervention should be considered. The hypothesis of this study is iliac bone marrow plasma injection after arthroscopic debridement of degenerative tissue will bring along biological cure. Thus, it will not only reduce pain but also improve function in patients with resistant elbow tendonitis.

Materials and Methods: Twenty-four patients (26 elbows) with significant persistent pain for a mean of 15 months, despite of standard rehabilitation protocol and a variety of other nonsurgical modalities were treated arthroscopically. We applied autologous iliac bone marrow plasma injection following arthroscopic debridement. This material is produced by centrifugation of iliac bone marrow blood at 1,800 rpm for 20 to 30 minutes. Patients were allowed full range of motion (ROM) exercise after 2 to 3 days. Cytokine analyses for this injective material were done. Outcome was rated by postoperative sonography, visual analog pain scores (VAS) and Mayo elbow performance scores (MEPS) at 8 weeks and 6 months follow-up. Informed consent had been obtained from the subjects, and the study protocol was approved by the ethics committee of Chosun University Hospital, Korea.

Results: All patients in this study noted improvement both in their VAS and MEPS. No complication occurred in any patient. Evidence of tendon healing was observed in postoperative songraphic examination. Predominant cytokines of this study were interleukin-12 (IL-12), interferon-gammainducible protein-10 (IP-10) and RANTES.

Conclusion: Biologic treatments in orthopaedics are just beginning to evolve. In the present investigation, the injection of iliac bone marrow plasma after arthroscopic debridement in severe elbow tendinosis demonstrated early recovery of daily activities and clear improvement.

Keywords: Epicondylitis, Iliac bone marrow plasma, Tendinosis
Nasal Obstruction in Children with Sleep-disordered Breathing
Authors: Sullivan Shannon , Li Kasey , Guilleminault Christian
Published: February 2023

Introduction: Nasal obstruction secondary to pathological enlargement of inferior nasal turbinates contributes to sleep-disordered breathing (SBD) in prepubertal children, but treatments designed to address turbinate enlargement are often not performed. The aims of these studies are: (1) to appreciate the contribution to SDB of untreated enlarged nasal turbinates in prepubertal children; and (2) to report our experience with treatment of enlarged nasal turbinates in young children with SDB.

Materials and Methods: Children with enlarged nasal turbinates who underwent adenotonsillectomy (T&A) had significantly less improvement in postoperative apnoea-hypopnoea index (AHI) compared to those treated with concomitant turbinate reduction. Children in the untreated turbinate hypertrophy group subsequently underwent radiofrequency ablation of the inferior nasal turbinates; following this procedure, AHI was no different than AHI of those without hypertrophy.

Results: In an analysis of safety and effectiveness of radiofrequency treatment of the nasal turbinates, we found the procedure to be a well-tolerated component of SDB treatment.

Conclusions: We conclude that radiofrequency (RF) treatment of inferior nasal turbinates is a safe and effective treatment in young prepubertal children with SDB. When indicated, it should be included in the treatment plan for prepubertal children with SDB. However, the duration of effectiveness is variable and therapy may need to be repeated if turbinate hypertrophy recurs.

Key words: Nasal inferior turbinates, Obstructive sleep apnoea, Pre-pubertal, Radiofrequency
Inflammatory Cytokines and Childhood Obstructive Sleep Apnoea
Authors: Li Albert M , Lam Hugh S , Chan Michael HM , So Hung K , Ng Siu K , Chan Iris HS , Lam Christopher WK , Wing Yun K
Published: February 2023

Objective: To evaluate serum cytokine concentrations in children with and without obstructive sleep apnoea (OSA) and to investigate the effects of OSA treatment on cytokines.

Materials and Methods: Consecutive children with habitual snoring and symptoms suggestive of OSA were recruited. They completed a sleep apnoea symptom questionnaire, underwent physical examination and overnight polysomnography (PSG). OSA was diagnosed if obstructive apnoea index (OAI) >1. A blood sample was collected for analysis of IL-6, IL-8, and TNF-α after PSG.

Results: One hundred forty-two children (97 males) with a median (IQR) age of 11.1 years (9.0-12.8) were recruited. The commonest presenting symptoms were nocturnal mouth breathing, prone sleeping position and poor attention at school. Forty-seven children were found to have OSA and they had higher serum IL-6 [0.1 (0.1-0.4) vs 0.1 (0.1-0.1) pg/mL, P = 0.001] and IL-8 [1.7 (1.0-2.3) vs 1.3 (0.9-1.7) pg/mL, P = 0.029] concentrations compared to their non-OSA counterparts. Multiple regression analysis indicated that OAI was significantly associated with both IL-6 (r = 0.351, P <0.001) and IL-8 (r = 0.266, P = 0.002). Sixteen children underwent treatment and there was significant reduction in mean (SD) serum IL-8 after intervention [pre vs post levels of 1.9 (1.0) vs 1.1 (0.6) pg/mL, P = 0.001] independent of weight loss.

Conclusion: Children with OSA had elevated levels of pro-inflammatory cytokines that normalised following treatment suggesting that the inflammatory response is potentially reversible. Early detection and intervention may be beneficial.

Key words: Interleukin 6, Interleukin 8, Polysomnography, Tumour necrosis factor
Basic Science Review on Circadian Rhythm Biology and Circadian Sleep Disorders
Authors: Toh Kong Leong
Published: February 2023

The sleep-wake cycle displays a characteristic 24-hour periodicity, providing an opportunity to dissect the endogenous circadian clock through the study of aberrant behaviour. This article surveys the properties of circadian clocks, with emphasis on mammals. Information was obtained from searches of peer-reviewed literature in the PUBMED database. Features that are highlighted include the known molecular components of clocks, their entrainment by external time cues and the output pathways used by clocks to regulate metabolism and behaviour. A review of human circadian rhythm sleep disorders follows, including recent discoveries of their genetic basis. The article concludes with a discussion of future approaches to the study of human circadian biology and sleep-wake behaviour.

Key words: Circadian clocks, Entrainment, Human circadian sleep-wake disorders
Functional Neuroimaging of Sleep Deprived Healthy Volunteers and Persons with Sleep Disorders: A Brief Review
Authors: Chuah Lisa YM , Chee Michael WL
Published: February 2023

Sleep loss can severely impact on the integrity of cognitive functions. This review highlights the recent functional neuroimaging studies on the brain’s response while performing cognitive tasks when deprived of sleep. Among sleep-deprived healthy volunteers, reduced attention, accompanied by lowered parieto-occipital activation, may underlie performance decrements seen in other “higher cognitive domains”. Functional neuroimaging in this setting has increased our understanding of how the brain responds to, and compensates for, sleep loss. Functional neuroimaging may also provide a safe, reproducible and non-invasive means to evaluate the cognitive and neural impact of therapeutic interventions designed to treat sleep disorders and/ or to reduce the negative cognitive impact of sleep loss.

Key words: Attention, Cognition, Functional neuroimaging, Memory, Sleep deprivation
The Scope of Paediatric Sleep Medicine
Authors: Teng Arthur Y , McNamara David G
Published: February 2023

Despite apparent similarities to adult sleep medicine, the disorders of paediatric sleep medicine have a distinct epidemiology and pathophysiology. During childhood, the physiology of sleep develops and matures, resulting in changing patterns of normal behaviours and of sleep disorders. Through a fictional case scenario, this article aims to convey the range and complexity of disorders that may be encountered and the various investigations and treatments available to the paediatric sleep physician.
Key words: Child, Circadian rhythm, Neuromuscular diseases, Obstructive sleep apnoea, Restless leg syndrome
Diagnosis and Evaluation of Obstructive Sleep Apnoea in Children
Authors: Brooks Lee J
Published: February 2023

Introduction: The aim of this article is to review the medical literature and describe clinical and laboratory findings in children with obstructive sleep apnoea (OSA) to differentiate children with OSA from those with primary snoring or other disorders, with a particular focus on Asian children.

Methods: Medline search via Pub Med, search terms sleep apnoea and children; and sleep apnoea and children and Asian.

Results and Conclusions: Children with OSA usually present with snoring, daytime sleepiness, and/or difficulties in school or behaviour. The prevalence of OSA in Asian children is less than that of other groups, but the severity of the disorder on presentation may be greater. Overnight polysomnography remains the diagnostic “gold standard”; limited studies, or studies in the home, are not sufficient to exclude OSA in a child with suggestive symptoms, nor can they reliably assess the severity of the disorder which is important in planning treatment. Limited studies may, however, be useful in large-scale research studies.

Key words: Asian, Polysomnography, Sleep studies, Snoring
Cardiovascular Changes in Children with Snoring and Obstructive Sleep Apnoea
Authors: Kwok Ka-li , Ng Daniel K , Chan Chung-hong
Published: February 2023

Introduction: Adults with obstructive sleep apnoea (OSA) are well documented to be at high risk for cardiovascular abnormalities. Growing evidence suggests that OSA is also associated with cardiovascular consequences in children. The purpose of this review is to examine the available data on this association in children.

Methods: Primary studies were extracted from a MEDLINE search limited to those published between 1970 and 2008. The keywords used included child, sleep disordered breathing, sleep apnoea, snoring, blood pressure and hearts. The relevant articles were selected by consensus between 2 authors.
Results: The results suggested that OSA was consistently associated with hypertension. Meta-analysis of risk of hypertension in those with high apnoea-hypopnoea index was undertaken. A combined odds ratio equal to 3.15 was found (95% confidence interval, 2.01 to 4.93). There was evidence for increased sympathetic activation, decreased arterial distensibility and ventricular hypertrophy in children with OSA. Conclusion: Childhood OSA is associated with blood pressure dysregulation. The association of OSA with other cardiovascular morbidities requires further study in view of the limited data available currently.

Key words: Atherosclerosis, Child, Hypertension
Observational Study to Determine Factors Associated with Blood Sample Haemolysis in the Emergency Department
Authors: Ong Marcus EH , Chan Yiong Huak , Lim Chin Siah
Published: February 2023

Introduction: Haemolysis of blood samples is a common problem encountered in the Emergency department (ED). It leads to inaccurate blood results and has cost implications as blood samples very often have to be retaken. The purpose of our study was to determine which factors in blood sampling were associated with higher rates of haemolysis.

Materials and Methods: An observational convenience sample of all patients presenting to the ED requiring blood urea and electrolyte (UE) analysis were eligible for our study. Questionnaires were distributed to the doctors and nurses conducting blood sampling to determine the method used and outcome data were collected after the samples were processed.

Results: Out of 227 UE samples analysed, 45 (19.8%) were haemolysed. Various factors, including method (IV cannulation or venepuncture), system (syringe or vacutainer), operator, rate of blood flow, difficulty of cannulation/venepuncture and source of blood (arterial or venous), were analysed, but their effects on haemolysis were not statistically significant (P >0.05). However, the use of the vacutainer system was associated with the highest rates of haemolysis [adjusted odds ratio (OR), 6.0; 95% confidence interval (CI), 2.3 to 15.1].

Conclusion: We found blood sampling with the vacutainer system to have increased rates of haemolysis. This could potentially change attitudes towards equipment used for blood sampling in the ED.

Key words: Chemistry testing, Emergency department, Sample haemolysis, Venepuncture, Venous cannulation
Ten-year Series of Splenic Abscesses in a General Hospital in Singapore
Authors: Ng Chee Yung , Leong E Chuan , Chng Hong Chee
Published: February 2023

Introduction: Splenic abscess is an uncommon clinical problem. Traditionally, the “gold standard” treatment has been splenectomy. However, there is increasing use of non-operative treatments worldwide.

Materials and Methods: A 10-year (1996-2005) retrospective review of case records from a single centre (an 800-bed general hospital) was performed. Information regarding demographics, clinical presentation, aetiological agents and management was gathered and analysed.

Results: There were 21 cases from 1996 to 2005. Nineteen (90%) had multiple abscesses. Disseminated melioidosis was the most common aetiological agent (15 cases, 71%). Only 3 patients underwent splenectomy. The remainder were treated conservatively with antibiotics. Almost all the patients (19, 90%) also suffered from diabetes mellitus.

Conclusions: The most common aetiological agent encountered was Burkholderia pseudomallei. Diabetes mellitus may be an important co-factor in the pathogenesis of splenic abscesses. The majority of our patients were managed conservatively and splenectomy was only occasionally required.

Key words: Burkholderia pseudomallei, Splenectomy
Diabetic Retinopathy in Diabetics Referred to a Tertiary Centre from a Nationwide Screening Programme
Authors: Lim Marcus CC , Lee Shu Yen , Cheng Bobby CL , Wong Doric WK , Ong Sze Guan , Ang Chong Lye , Yeo Ian YS
Published: February 2023

Introduction: The aim of the study was to describe the prevalence and risk factors for diabetic retinopathy in a multi-ethnic diabetic patient cohort referred for retinal evaluation from a nationwide diabetic retinopathy screening programme in Singapore.

Materials and Methods: Seven hundred and forty-two patients, aged 21 to 95, referred for suspected diabetic retinopathy on annual one-field non-mydriatic 45 degree retinal photographs (Topcon TRC-NW6, Topcon Corporation, Tokyo, Japan) from primary care to the Singapore National Eye Centre diabetic retinopathy clinic were included. The photographs had been interpreted by 24 trained family physicians accredited every 2 years with a training programme. Patients underwent a standardised interview and examination. Fundi were examined with indirect ophthalmoscopy by 2 examiners. Presence and severity of diabetic retinopathy was graded into none, mild, moderate, severe, very severe non-proliferative diabetic retinopathy and proliferative diabetic retinopathy. Macular oedema and clinically significant macular oedema were also graded.

Results: Ninety-nine per cent of patients were type 2 diabetics. The prevalence of diabetic retinopathy was 38.1%, visionthreatening retinopathy was 11.8% and macular oedema was 6.9%. There were no racial differences. Significant predictors of any retinopathy were longer duration of diabetes, lower body mass index, being on treatment for hypertension, hypercholesterolaemia and use of diabetic medication. Predictors for vision-threatening retinopathy were younger age, longer duration of diabetes and lower body mass index.

Conclusions: The use of one-field non-mydriatic 45 degree photography as a screening tool for diabetic retinopathy resulted in a cohort of which 38.1% had diabetic retinopathy. Risk factors for diabetic retinopathy of this cohort are also presented.

Key words: Diabetic retinopathy, Epidemiology, Ethnology, Singapore, Screening