Lytic to temperate switching of viral communities.

Microbial viruses can control host abundances via density-dependent lytic predator-prey dynamics. Less clear is how temperate viruses, which coexist and replicate with their host, influence microbial communities. Here we show that virus-like particles are relatively less abundant at high host densities. This suggests suppressed lysis where established models predict lytic dynamics are favoured. Meta-analysis of published viral and microbial densities showed that this trend was widespread in diverse ecosystems ranging from soil to freshwater to human lungs. Experimental manipulations showed viral densities more consistent with temperate than lytic life cycles at increasing microbial abundance. An analysis of 24 coral reef viromes showed a relative increase in the abundance of hallmark genes encoded by temperate viruses with increased microbial abundance. Based on these four lines of evidence, we propose the Piggyback-the-Winner model wherein temperate dynamics become increasingly important in ecosystems with high microbial densities; thus 'more microbes, fewer viruses'.

What influences use of dental services by the Korean disabled people? The role of perceived barriers in dental care system.

OBJECTIVE: To identify the perceived barriers to dental care for disabled people in South Korea using the revised Andersen's model of access to health care. BASIC RESEARCH DESIGN: Cross-sectional analytic interview study. PARTICIPANTS: Korean people with a disability residing in residential facilities, or those at home who attend vocational rehabilitation facilities, special schools, or welfare facilities, were sampled from Seoul and non-Seoul areas in 2016 and were interviewed face-to-face. In total, 456 disabled Koreans, or their primary caregivers participated. RESULTS: Household income, disability duration and perceived barriers in the dental care system were perceived to impact on dental care utilisation, while the need for dental care services did not significantly explain the use of dental care by disabled people in South Korea. Those with low household incomes were less likely to use dental care services, compared to people with moderate and high household incomes. As disability duration increased, disabled people were more likely to use dental services. Those who perceived the barriers to dental care as higher were less likely to use dental services. CONCLUSION: These data suggest that policies are needed to support disabled people with low household incomes. Lowering barriers in the dental care system may encourage people with disabilities to access timely and adequate dental services.

Predisposing factors associated with atypical femur fracture among postmenopausal Korean women receiving bisphosphonate therapy: 8 years' experience in a single center.

The risk factors for atypical femur fracture in patients exposed to bisphosphonates for at least 1 year were examined. Prolonged and continuous use of bisphosphonates, long-term use of glucocorticoids, and a higher body mass index were associated with increased risk of atypical femur fracture. INTRODUCTION: The purpose of the present study is to determine whether rheumatoid arthritis (RA) and other clinical factors are associated with an increased risk of bisphosphonate (BP)-related atypical femur fracture (AFF). METHODS: A retrospective nested case-control study of patients who had taken BPs for at least 1 year was conducted. Patients with AFF were identified by reviewing surgical and radiographic records. Three controls with no history of AFFs were randomly selected and age- and sex-matched to each patient with AFFs. Cox proportional hazard models were used to analyze the independent contribution of risk factors to BP-related AFF. RESULTS: Among the 35,104 patients prescribed BPs for at least 1 year, 43 females (mean age, 68 years) suffered AFFs (0.12%). Patients with AFFs were exposed to BPs for a mean of 7.3 years. Patients with AFFs were exposed to BPs for longer than those without AFFs and continued treatment without a drug holiday. More patients with AFF than controls had taken glucocorticoids and disease-modifying anti-rheumatic drugs. Multivariate Cox regression analyses estimated that long-term use of glucocorticoids, prolonged exposure to BP without cessation, and every 1 kg/m2 increase in the body mass index (BMI) increased the hazard ratio for AFFs by 3.0, 5.2, and 1.2, respectively. CONCLUSIONS: Prolonged and continuous use of BPs, long-term use of glucocorticoids, and a higher BMI increase the risk of AFFs. Switching long-term BP and glucocorticoid users to other bone-protective agents should be considered.

Therapeutic applications of germline testing for cancer predisposition genes in Asia in the real world.

BACKGROUND: Germline genetic testing is traditionally carried out in patients suspected with hereditary cancer syndrome for enhanced cancer surveillance and/or preventive strategies, but is increasingly carried out for therapeutic indications. MATERIALS AND METHODS: We conducted a retrospective review of patients who underwent germline genetic testing at our centre to determine the prevalence of actionable pathogenic germline variants (PGV) and their clinical utility. RESULTS: From 2000 to 2022, 1154 cancer patients underwent germline testing, with the majority (945/1154) tested with multi-gene panels. Four hundred and eleven (35.6%) patients harboured a PGV and 334 (81%) were clinically actionable. BRCA1/2 accounted for 62.3% of actionable mutations, followed by mismatch repair (18%), and other homologous recombination repair (HRR) genes (19.7%). One hundred and fifty-two germline-positive patients have advanced cancers, and 79 received germline-directed therapies (poly ADP ribose polymerase inhibitors = 75; immunotherapy = 4). Median duration of immunotherapy and poly ADP ribose polymerase were 20.5 months (range 5-40 months) and 8 months (range 1-76 months), respectively. Among BRCA/HRR mutation carriers who received platinum-based chemotherapy, pathological complete response rate in the neoadjuvant setting was 53% (n = 17 breast cancers) and objective response rate was >80% in the advanced setting (n = 71). CONCLUSIONS: One-third of cancer patients tested carried a PGV and ∼80% were clinically actionable. Three-quarters of germline-positive advanced cancer patients received germline-directed therapies in the real world, underscoring the practical utility of germline testing to guide cancer therapeutics.

Quantifying the natural history of breast cancer.

BACKGROUND: Natural history models of breast cancer progression provide an opportunity to evaluate and identify optimal screening scenarios. This paper describes a detailed Markov model characterising breast cancer tumour progression. METHODS: Breast cancer is modelled by a 13-state continuous-time Markov model. The model differentiates between indolent and aggressive ductal carcinomas in situ tumours, and aggressive tumours of different sizes. We compared such aggressive cancers, that is, which are non-indolent, to those which are non-growing and regressing. Model input parameters and structure were informed by the 1978-1984 Ostergotland county breast screening randomised controlled trial. Overlaid on the natural history model is the effect of screening on diagnosis. Parameters were estimated using Bayesian methods. Markov chain Monte Carlo integration was used to sample the resulting posterior distribution. RESULTS: The breast cancer incidence rate in the Ostergotland population was 21 (95% CI: 17-25) per 10 000 woman-years. Accounting for length-biased sampling, an estimated 91% (95% CI: 85-97%) of breast cancers were aggressive. Larger tumours, 21-50 mm, had an average sojourn of 6 years (95% CI: 3-16 years), whereas aggressive ductal carcinomas in situ took around half a month (95% CI: 0-1 month) to progress to the invasive ≤10 mm state. CONCLUSION: These tumour progression rate estimates may facilitate future work analysing cost-effectiveness and quality-adjusted life years for various screening strategies.

Diversity and decay ability of basidiomycetes isolated from lodgepole pines killed by the mountain pine beetle.

When lodgepole pines (Pinus contorta Douglas ex Louden var. latifolia Engelm. ex S. Watson) that are killed by the mountain pine beetle (Dendroctonus ponderosae) and its fungal associates are not harvested, fungal decay can affect wood and fibre properties. Ophiostomatoids stain sapwood but do not affect the structural properties of wood. In contrast, white or brown decay basidiomycetes degrade wood. We isolated both staining and decay fungi from 300 lodgepole pine trees killed by mountain pine beetle at green, red, and grey stages at 10 sites across British Columbia. We retained 224 basidiomycete isolates that we classified into 34 species using morphological and physiological characteristics and rDNA large subunit sequences. The number of basidiomycete species varied from 4 to 14 species per site. We assessed the ability of these fungi to degrade both pine sapwood and heartwood using the soil jar decay test. The highest wood mass losses for both sapwood and heartwood were measured for the brown rot species Fomitopsis pinicola and the white rot Metulodontia and Ganoderma species. The sap rot species Trichaptum abietinum was more damaging for sapwood than for heartwood. A number of species caused more than 50% wood mass losses after 12 weeks at room temperature, suggesting that beetle-killed trees can rapidly lose market value due to degradation of wood structural components.

Pharmacokinetics and pharmacodynamics of docetaxel with or without ketoconazole modulation in chemonaive breast cancer patients.

BACKGROUND: We previously found 70 mg flat-dose docetaxel coadministered with ketoconazole to modulate CYP3A4 to be the maximum tolerated dose that resulted in comparable docetaxel area under the plasma concentration-time curve (AUC) as 75-100 mg/m² docetaxel. PATIENTS AND METHODS: We compared cycle 1 docetaxel pharmacokinetics and pharmacodynamics between ketoconazole-modulated (70 mg flat-dose docetaxel, n = 31) and conventional-dosed docetaxel (75 mg/m², n = 51) in chemonaive breast cancer patients in two sequential phase II studies. RESULTS: Ketoconazole-modulated docetaxel resulted in reduced docetaxel clearance (22.05 ± 8.29 versus 36.52 ± 13.39 l/h, P < 0.001), similar docetaxel AUC (3.93 ± 2.77 versus 3.77 ± 2.70 mg/l·h, P = 0.794) and tumor efficacy (cycle 1 responder 52% versus 55%) and less day 8 neutrophil suppression (1.24 ± 1.02 × 109/l versus 0.47 ± 0.56 × 109/l, P < 0.001), grade 4 neutropenia (32.3% versus 72.0%, P < 0.001) and febrile neutropenia (3.2 versus 23.5%, P = 0.015), compared with conventional-dosed docetaxel. Chinese had the lowest docetaxel clearance, highest AUC and most myelosuppression, followed by Malays and Indians, in response to ketoconazole-modulated docetaxel, while no significant interethnic differences were observed with conventional-dosed docetaxel. CONCLUSIONS: Ketoconazole-modulated docetaxel achieved similar docetaxel AUC and tumor efficacy but reduced neutrophil suppression and febrile neutropenia at ∼40% reduced dose, representing a feasible alternative to conventional-dosed docetaxel. Interethnic differences in CYP3A4 inhibition by ketoconazole exist and are important when evaluating the impact of concomitant medications.

Effect of leg-length discrepancy following total hip arthroplasty on collapse of the contralateral hip in bilateral non-traumatic osteonecrosis of the femoral head.

AIMS: The purpose of this study was to examine whether leg-length discrepancy (LLD) following unilateral total hip arthroplasty (THA) affects the incidence of contralateral head collapse and subsequent THA in patients with bilateral osteonecrosis, and to determine factors associated with subsequent collapse. PATIENTS AND METHODS: We identified 121 patients with bilateral non-traumatic osteonecrosis who underwent THA between 2003 and 2011 to treat a symptomatic hip, and who also exhibited medium-to-large lesions (necrotic area ≥ 30%) in an otherwise asymptomatic non-operated hip. Of the 121 patients, 71 were male (59%) and 50 were female (41%), with a mean age of 51 years (19 to 71) at the time of initial THA. All patients were followed for at least five years and were assessed according to the presence of a LLD (non-LLD vs LLD group), as well as the LLD type (longer non-operated side vs shorter non-operated side group). RESULTS: Overall, 68 hips (56%) became painful and progressed to collapse at a mean of 2.6 years (0.2 to 13.8), resulting in 59 THAs (49%). The five-year collapse-free survival rate for the non-LLD group was 59% (95% confidence interval (CI) 46.8 to 71.8) compared with 45% (95% CI 32.9 to 57.5) for the LLD group (p = 0.036), and 66% (95% CI 55.2 to 77.2) for the longer non-operated side group compared with 32% (95% CI 19.1 to 44.9) for the shorter non-operated side group (p < 0.001). Multivariate regression analyses found that large lesions had a higher risk of collapse than medium-size lesions (odds ratio (OR) 4.19, 95% confidence interval (CI) 1.69 to 10.38; p = 0.002). Meanwhile, patients with a LLD < 3 mm (OR 0.20, 95% CI 0.08 to 0.52; p = 0.001) or a longer non-operated leg (OR 0.11, 95% CI 0.04 to 0.28; p < 0.001) after THA were less likely to experience a subsequent collapse. CONCLUSION: We found that LLD may be a modifiable risk factor for femoral head collapse. Minimizing LLD and particularly avoiding a shorter non-operated limb after THA may lead to a lower risk of collapse of the asymptomatic hip in patients with bilateral non-traumatic osteonecrosis. Cite this article: Bone Joint J 2019;101-B:303-310.

PXR, CAR and HNF4alpha genotypes and their association with pharmacokinetics and pharmacodynamics of docetaxel and doxorubicin in Asian patients.

Previously studied candidate genes have failed to account for inter-individual variability of docetaxel and doxorubicin disposition and effects. We genotyped the transcriptional regulators of CYP3A and ABCB1 in 101 breast cancer patients from 3 Asian ethnic groups, that is, Chinese, Malays and Indians, in correlation with the pharmacokinetics and pharmacodynamics of docetaxel and doxorubicin. While there was no ethnic difference in docetaxel and doxorubicin pharmacokinetics, ethnic difference in docetaxel- (ANOVA, P=0.001) and doxorubicin-induced (ANOVA, P=0.003) leukocyte suppression was observed, with Chinese and Indians experiencing greater degree of docetaxel-induced myelosuppression than Malays (Bonferroni, P=0.002, P=0.042), and Chinese experiencing greater degree of doxorubicin-induced myelosuppression than Malays and Indians (post hoc Bonferroni, P=0.024 and 0.025). Genotyping revealed both PXR and CAR to be well conserved; only a PXR 5'-untranslated region polymorphism (-24381A>C) and a silent CAR variant (Pro180Pro) were found at allele frequencies of 26 and 53%, respectively. Two non-synonymous variants were identified in HNF4alpha (Met49Val and Thr130Ile) at allele frequencies of 55 and 1%, respectively, with the Met49Val variant associated with slower neutrophil recovery in docetaxel-treated patients (ANOVA, P=0.046). Interactions were observed between HNF4alpha Met49Val and CAR Pro180Pro, with patients who were wild type for both variants experiencing least docetaxel-induced neutropenia (ANOVA, P=0.030). No other significant genotypic associations with pharmacokinetics or pharmacodynamics of either drug were found. The PXR-24381A>C variants were significantly more common in Indians compared to Chinese or Malays (32/18/21%, P=0.035) Inter-individual and inter-ethnic variations of docetaxel and doxorubicin pharmacokinetics or pharmacodynamics exist, but genotypic variability of the transcriptional regulators PAR, CAR and HNF4alpha cannot account for this variability.

The biological response to laser-aided direct metal-coated Titanium alloy (Ti6Al4V).

OBJECTIVES: Laser-engineered net shaping (LENS) of coated surfaces can overcome the limitations of conventional coating technologies. We compared the in vitro biological response with a titanium plasma spray (TPS)-coated titanium alloy (Ti6Al4V) surface with that of a Ti6Al4V surface coated with titanium using direct metal fabrication (DMF) with 3D printing technologies. METHODS: The in vitro ability of human osteoblasts to adhere to TPS-coated Ti6Al4V was compared with DMF-coating. Scanning electron microscopy (SEM) was used to assess the structure and morphology of the surfaces. Biological and morphological responses to human osteoblast cell lines were then examined by measuring cell proliferation, alkaline phosphatase activity, actin filaments, and RUNX2 gene expression. RESULTS: Morphological assessment of the cells after six hours of incubation using SEM showed that the TPS- and DMF-coated surfaces were largely covered with lamellipodia from the osteoblasts. Cell adhesion appeared similar in both groups. The differences in the rates of cell proliferation and alkaline phosphatase activities were not statistically significant. CONCLUSIONS: The DMF coating applied using metal 3D printing is similar to the TPS coating, which is the most common coating process used for bone ingrowth. The DMF method provided an acceptable surface structure and a viable biological surface. Moreover, this method is automatable and less complex than plasma spraying.Cite this article: T. Shin, D. Lim, Y. S. Kim, S. C. Kim, W. L. Jo, Y. W. Lim. The biological response to laser-aided direct metal-coated Titanium alloy (Ti6Al4V). Bone Joint Res 2018;7:357-361. DOI: 10.1302/2046-3758.75.BJR-2017-0222.R1.

Tumor molecular profiling of responders and non-responders following pembrolizumab monotherapy in chemotherapy resistant advanced cervical cancer.

Optimal treatment for advanced cervical cancer after first line chemotherapy remains undefined. Immune checkpoint inhibition with pembrolizumab, a programmed cell death protein 1(PD-1) inhibitor, is under investigation. We analyzed the micro-environmental and molecular genetic profile of tumors from 4 patients with metastatic cervical cancer treated with off-label second-line pembrolizumab in an effort to identify predictive biomarkers. All patients received 2 mg/kg of pembrolizumab, 3-weekly until disease progression. Immunohistochemistry(IHC) for PD-1, PD-L1, CD3 and CD8, as well as next generation sequencing (NGS) for 50 cancer-related genes were performed on tumor samples. All patients tolerated treatment well with no discontinuation of treatment due to toxicity. One patient experienced dramatic and prolonged partial response, and remains stable on pembrolizumab with a progression free survival (PFS) of 21 months at the time of reporting of this series. Three patients experienced disease progression as best response. In the exceptional responder, there was no tumoral expression of PD-L1, however, combined positive score (CPS) for PD-L1 was 1 and we identified somatic mutations in ERBB4(R612W), PIK3CA(E542K) and RB1(E365K). In 2 patients, despite progressive disease defined by RECIST v1.1, symptom stabilization on pembrolizumab was observed. The tumors of both patients had PD-1 expression in ≥1% of stromal lymphocytes. All patients with response or clinical benefit had CPS for PD-L1 ≥ 1. NGS revealed PIK3CA mutations in 3 tumors. Pembrolizumab is a promising therapeutic option in advanced cervical cancer. Further evaluation of biomarkers may guide optimal patient selection.

A systematic review of methods to measure family co-participation in physical activity.

The family environment is key in influencing children's health behaviours. Encouraging family co-participation in physical activity may therefore be an effective approach to increasing children's physical activity levels. Yet, little is known about how to best assess family co-participation in physical activity. This review summarizes methods to measure family co-participation in physical activity, which was defined as joint physical activities including at least one healthy child (0-18 years) and one other family member. Methods were identified through a systematic literature search, cross-referencing pre-selected reviews and contacting research groups. Thirty-seven measurement methods were included. Questionnaires were the most common method used, with the majority assessing frequency of co-participation and few also assessing duration and type. Reliability and internal consistency of scales were often reported, but rarely specified for the item(s) relevant to co-participation. Other methods of measuring co-participation included diaries, event history calendars, direct observations and accelerometry combined with diary, ecological momentary assessment or global positioning systems (GPS). Whilst a large number of measurement methods of family co-participation in physical activity exist, few are comprehensive and/or report acceptable psychometric properties. Future work should focus on reaching consensus in defining family co-participation in physical activity, and subsequently developing reliable and valid measures.

Hereditary neuropathy with liablity to pressure palsies.

Hereditary neuropathy with liability to pressure palsies (HNPP) is a disease that presents with recurrent reversible episodes of neurapraxia that occur typically after trivial trauma. It is an autosomal dominant, demyelinating neuropathy. A 20-year-old man presented with left ulnar nerve palsy after a fall. He had reduced two-point discrimination over his left ulnar nerve distribution, with mild clawing of the ring and little fingers, and accompanying weakness of the first dorsal interrosseus and abductor digiti minimi of grade four power. His Froment's sign was also positive. Careful clinical examination and appropriate tests, including electromyography and genetic testing, confirmed the diagnosis of HNPP. This case report is presented to promote awareness and recognition of this disease in the local and regional context.

True digital artery aneurysm of the ring finger: a case report.

True aneurysms of the digital artery are very rare. Only 13 cases, caused by chronic trauma from occupational or sports-related overuse, have been reported. We present the first case of a true aneurysm of the digital artery of the left ring finger caused by chronic repetitive trauma from a wedding ring. The patient was a 44-year-old teacher who presented with a 1.5-cm subcutaneous mass on the radial aspect of the proximal phalanx of the finger, just proximal to the proximal interphalangeal joint. Exploration of the mass revealed a 1-cm aneurysm continuous with the radial digital artery. The aneurysm was excised and the proximal and distal ends of the radial digital artery ligated. Microscopic examination of the excised specimen confirmed the diagnosis of a true aneurysm with the lumen filled with an organising thrombus. The patient had an uneventful recovery with good wound healing, intact sensation, and normal capillary return.

Preventing childhood obesity in Asia: an overview of intervention programmes.

The rapid economic growth in Asia in the past few decades has contributed to the global increase in childhood obesity prevalence. Yet, little is known about obesity prevention efforts in this region. This systematic review provides an overview of child obesity prevention programmes in Asia. Searches were performed in six electronic databases. Out of 4,234 studies, 17 were included, among them 11 controlled trials (of which five were randomized). Only one study was published before 2007. Identified studies were predominantly conducted in China and Thailand and targeted primary school children in a school setting. Most studies implemented different programmes, frequently targeting behavioural modification through nutrition/health education lectures and/or physical activity sessions. Programme effects related to obesity outcome measures were mixed. Most substantial effects were found for outcomes such as improved health knowledge and/or favourable lifestyle practices. The relatively small number of relevant publications in Asia highlights the need for scientific evaluations of existing and future programmes. This will help ensure the implementation and dissemination of evidence-based approaches that have been proven to be effective in the Asian context. Targeting preschool settings and applying a comprehensive multisectoral approach may increase the effectiveness and sustainability of childhood obesity prevention programmes.

Treatment of benign giant cell tumours of bone in Singapore.

INTRODUCTION: Giant cell tumour (GCT) is a distinct neoplasm of undifferentiated cells. The exact cell of origin is unknown. The multinucleated giant cells present are formed from the fusion of mononuclear cells. Giant cell tumour is more common in Southeast Asia than in the West. The incidence is about 20% compared to 4% to 5% in the West. MATERIALS AND METHODS: Sixteen patients with giant cell tumour were treated in the Singapore General Hospital from 1993 to 2001. The average follow-up period was 64.4 months, with a range of 30 to 132 months. The average age of the patients was 33 years. The tumours were divided into 3 groups. The first group had meticulous curettage and high-speed burring followed by methylmethacrylate cementation. The second group had treatment similar to the first but in addition had an adjuvant treatment with liquid nitrogen, hydrogen peroxide or phenol before cementation of the cavity. The third group had wide resection done. There were 9 in the first group, 5 in the second group and 2 in the third group. The tumours were graded radiologically after the method of Campanacci et al. All patients were followed up clinically and radiologically. Of the 5 in the second treatment group, 1 had phenol irrigation, 2 had cryotherapy and 2 had hydrogen peroxide irrigation intraoperatively. RESULTS: There was a total of 5 recurrences (31%). The 2-year recurrence-free survivorship was 75%. The mean recurrence period was 21 months. There were no complications like fracture, infection or thermal injury to the skin. There was no pulmonary metastasis or mortality. The first group, who had curettage, high-speed burr and cementation, had 44% (4 out of 9) recurrence; the second group, who had treatment like the first with additional adjuvant therapy, had no recurrence; and the third, who had wide resection, had 50% (1 out of 2) recurrence. All the recurrences had a Campanacci grade II or III tumour. There were no recurrences in the group that was treated with curettage, high-speed burr, adjuvant treatment and cementation. CONCLUSION: Currettage, high-speed burring with added phenol/liquid nitrogen treatment and cementation is a useful and safe method in the treatment of giant cell tumours. The advantages include a low recurrence rate, as well as immediate stabilisation allowing early mobilisation. Patients who have Campanacci grade I tumours have the highest chance of being disease-free after the first operation.

Post-poliomyelitis syndrome: case report and review of the literature.

INTRODUCTION: Postpoliomyelitis syndrome (PPS) refers to the new neuromuscular symptoms that occur in patients years after their acute poliomyelitis has stabilised. PPS cases seen now are probably related to the poliomyelitis epidemics of the 1940s and 1950s. CLINICAL PICTURE AND INVESTIGATION: A 57-year-old Chinese man with a history of poliomyelitis affecting both lower limbs presented with left upper limb weakness. Physical examination revealed atrophy of his left upper limb muscles. There were fasciculations in the biceps and brachioradialis muscles. Electromyography revealed ongoing denervation neurogenic units in the C5 to TI myotomes comparable with PPS. CONCLUSION: The aim of this paper is to review the present situation and to give a short summary of PPS, which can be difficult to diagnose because the symptoms of presentation are usually non-specific. We describe a case of PPS and review the current literature.

Broadband ultrasound attention reference database for southeast Asian males and females.

INTRODUCTION: The objective of this study was to establish the broadband ultrasound attenuation (BUA) measurements of the calcaneum for Southeast Asian males and females. A database was used to draw the reference curve for the Southeast Asian male and female population. MATERIALS AND METHODS: The database included 366 healthy females and 236 healthy males. We measured the BUA values of the left heel using the Contact Ultrasound Bone Analyser (CUBA) clinical system. RESULTS: The mean difference between Southeast Asian males and Caucasian males was 9.3 dB MHz-1 and that for females was 5.0 dB MHz-1. The standard deviations (SDs) for Southeast Asian female and male normative values were 17.43 and 20.10, respectively. This is comparable with the SD for the McCue Caucasian female and male normative data of 16.54 and 17.45 respectively. CONCLUSION: The study shows that the Southeast Asian population has a significantly lower normative value than the Caucasian population. This BUA reference database obtained will allow for more accurate determination of Southeast Asian patients at risk of osteoporosis.