Southeast Asian Populations Research Articles

Pruritic papular eruption revealing HIV

Pruritic papular eruption (PPE) described in HIV is a skin disease often encountered in HIV-positive patients. It is most often a sign of severe immunodeficiency and is commonly reported in African, Southeast Asian, and Indian populations [1,2]. It affects both adult females and males and may also be seen in children. The elementary lesion is a discrete, firm, erythematous, urticarial, very itchy papule of the extremities, face, and trunk, sparing the palms and soles. Painful excoriations in the genital mucosa are sometimes described. The CD4+ lymphocyte count (CD4) is usually below 250 cells/mm3. Histopathology reveals a lymphohistiocytic, inflammatory, perivascular, and periannexal infiltrate with a variable number of eosinophils. According to the World Health Organization (WHO), it is recommended to all HIV patients with antiretroviral therapy (ART), regardless of the staging and the CD4 count [3]. However, an elective treatment for PPE has not yet been found. Regression has been noted in some cases after the initiation of antiretroviral therapy. UVB therapy seems to be the most successful method in cases not improving with antiretroviral therapy [4]. Herein, we report the case of a patient who presented with PPE revealing HIV.

Volumetric evaluation of the sphenoid sinus among different races in the Southeast Asian (SEA) population: a computerized tomography study.

Introduction: The fundament of forensic science lies in identifying a body. The morphological complexity of the paranasal sinus (PNS), which varies greatly amongst individual, possess a discriminatory value that potentially contributes to the radiological identification. The sphenoid bone represents the keystone of the skull and forms part of the cranial vault. It is intimately associated with vital neurovascular structures. The sphenoid sinus, located within the body of the sphenoid bone, has variable morphology. The sphenoid septum's inconsistent position and the degree, as well as the direction disparities of sinus pneumatization, have indeed accorded it a unique structure in providing invaluable information in forensic personnel identification. Additionally, the sphenoid sinus is situated deep within the sphenoid bone. Therefore, it is well protected from traumatic degradation from external causes and can be potentially utilized in forensic studies. The authors aim to study the possibility of variation among the race, and gender in the Southeast Asian (SEA) population, using volumetric measurements of the sphenoid sinus. Materials and methods: This is a retrospective cross-sectional analysis of computerized tomographic (CT) imaging of the PNS of 304 patients (167 males, 137 females) in a single centre. The volume of the sphenoid sinus was reconstructed and measured using commercial real-time segmentation software. Result: The total volume of sphenoid sinus of male gender had shown to be larger, 12.22 (4.93 - 21.09) cm3 compared to the counterpart of 10.19 (3.75 - 18.72) cm3 (p = .0090). The Chinese possessed a larger total sphenoid sinus volume, 12.96 (4.62 - 22.21) cm3) than the Malays, 10.68 (4.13 - 19.25) cm3 (p = .0057). No correlation was identified between the age and volume of the sinus (cc= -.026, p = .6559). Conclusion: The sphenoid sinus volume in males was found to be larger than those of females. It was also shown that race influences sinus volume. Volumetric analysis of the sphenoid sinus can potentially be utilized in gender and race determination. The current study provided normative data on the sphenoid sinus volume in the SEA region, which can be helpful for future studies.

Insights on Health-related Quality of Life After Glioma Surgery in a South-East Asian Population

Insights on Health-related Quality of Life After Glioma Surgery in a South-East Asian Population

Validation of the Original, Alternative, Updated-alternative & Auditing Fistula Risk Score for Prediction of Fistula after Whipple's in a Southeast Asian Population

Validation of the Original, Alternative, Updated-alternative & Auditing Fistula Risk Score for Prediction of Fistula after Whipple's in a Southeast Asian Population

No significant post-operative limb length difference following medial opening wedge high tibial osteotomy in a multi-ethnic Southeast Asian population

PurposeThis study aims to assess the significance of post-operative change in limb length in medial opening wedge high tibial osteotomy (MOWHTO), and evaluate the correlation between correction angles and changes in limb length. We hypothesize that opening wedge height and correction angles directly correlate to changes in limb length.MethodsThe medical records and radiographs of 91 MOWHTO patients were retrospectively evaluated for relevant radiographical parameters both pre- and post-operatively. The exclusion criteria are: (i) concurrent distal femur osteotomy in the same setting, (ii) other previous unilateral lower limb surgeries prior to MOWHTO and (iii) failure to follow-up with post-operative radiographs. A linear regression model was performed and a line of best fit, Pearson's correlation coefficient (r) and coefficient of determination (R2) were computed. Chi-squared test was also performed, and results with P < 0.05 were considered statistically significant.ResultsThere is a statistically significant increase in post-MOWHTO limb length (Absolute Δ = 4.3 ± 2.86 mm, % Δ = 0.652% ± 0.434%, p < 0.001). There was no significant difference in the limb length change between patients with larger (> 8 mm) and smaller (< 8 mm) opening widths.There was a weakly positive correlation between limb length change versus actual (R2 = 0.140, 95%CI [-0.068, 0.336]) and planned correction angles (R2 = 0.196, 95%CI [-0.012, 0.387]).ConclusionIn conclusion, post-MOWHTO change in limb length is statistically significant, but the clinical significance is minimal. Further studies are required to assess other factors. Development of a reliable mathematical model that predicts post-MOWHTO limb length change would be useful in predicting the anatomical outcomes.Level of evidenceLevel III. Retrospective Cohort Study.

RELATIONSHIP OF LIFESTYLE AND DIETARY HABITS OF SOUTH-EAST ASIAN (PAKISTANI) POPULATION WITH CARDIOVASCULAR DISEASES: A CASE-CONTROL STUDY

Objectives: Cardiovascular disease (CVDs) is the leading cause of deaths globally. Apart from traditional risks, multiple indigenous factors are implicated to impact disease courses. Lifestyle factors distinct to South Asians may predispose to disease or serve a protective effect. Our study objective was to determine the Relationship of lifestyle and dietary habits of South-east Asian (Pakistani) population with cardiovascular diseases. Methodology: A case-control study was conducted from April to October 2021 in a two-thousand bedded university teaching hospital in Karachi, Pakistan. Out of 400 participants, 189 were cases with a documented cardiovascular event and 211 were controls. Participants &gt;18 years were included whereas pregnant females and patients with congenital heart defects were excluded. A structured questionnaire was designed and implemented, and anthropometrics were recorded. Chi-square test, independent sample t-test and multivariate analysis were utilized via SPSSv23. P-value &lt;0.05 was considered significant. Results: From 400 participants, 189 cases and 211 controls were identified. 53.4% of the people consuming open spices had CVDs while 46.6% did not. While only 37% of people using home cooked spices had CVDs with an OR= 0.51(0.3-0.84, 95% CI, p=0.08). Our results showed an inverse or no relationship of high BMI with CVDs. No statistically significant results were observed of diabetes and hypertension with CVDs. Conclusion: Based on our results, home grounded condiments have a protective effects on CVD than open spices. With reference to CVD, poor lifestyle habits and anthropometric profiles of our controls indicate a need for urgent preventive measures at population level.

Ancient DNA from Protohistoric Period Cambodia indicates that South Asians admixed with local populations as early as 1st–3rd centuries CE

Indian cultural influence is remarkable in present-day Mainland Southeast Asia (MSEA), and it may have stimulated early state formation in the region. Various present-day populations in MSEA harbor a low level of South Asian ancestry, but previous studies failed to detect such ancestry in any ancient individual from MSEA. In this study, we discovered a substantial level of South Asian admixture (ca. 40–50%) in a Protohistoric individual from the Vat Komnou cemetery at the Angkor Borei site in Cambodia. The location and direct radiocarbon dating result on the human bone (95% confidence interval is 78–234 calCE) indicate that this individual lived during the early period of Funan, one of the earliest states in MSEA, which shows that the South Asian gene flow to Cambodia started about a millennium earlier than indicated by previous published results of genetic dating relying on present-day populations. Plausible proxies for the South Asian ancestry source in this individual are present-day populations in Southern India, and the individual shares more genetic drift with present-day Cambodians than with most present-day East and Southeast Asian populations.

ASEAN 4.0. ERA: DEVELOPMENT IN DIGITAL ECONOMY AND TRADE SECTOR

The ASEAN Free Trade Area (AFTA) is the first step towards economic liberalization in Southeast Asia. Through AFTA, ASEAN member countries reduce to abolish tariffs on certain products in regional trade schemes. AFTA is a facility for the government to regulate what products will be exported and imported in accordance with applicable tariff rules, it makes the community very dependent on the government and large companies for these products. As technology develops and Southeast Asia's population grows, a digital era is formed in the trade sector that promotes more dynamic e-commerce. E-commerce makes people not dependent on the government and more independent in regional markets. Because it covers each individual and MSME with the convenience of digitalized cross-border transactions. The existence of e-commerce caused the trend to change, from where initially the community was very dependent on the government to becoming independent of the products set by the government. This study uses a qualitative-descriptive method with data collection techniques from literature studies from books, journals, official websites, and so on. The results of the study indicate that there has been a change in the trend of trade in ASEAN. This trend is due to the occurrence of digital transformation which provides opportunities for the MSME community to enter regional and global trade. Participation in regional trade in ASEAN is not only followed by state actors but also enlivened by non-state actors, especially all levels of ASEAN society who take advantage of developing e-commerce platforms.&#x0D; Keywords: Transformation, Digital, E-Commerce, Trade, ASEAN

Plasmodium cynomolgi in humans: current knowledge and future directions of an emerging zoonotic malaria parasite.

Plasmodium cynomolgi (Pcy), a simian malaria parasite, is a recent perfect example of emerging zoonotic transfer in human. This review summarizes the current knowledge on the epidemiology of natural Pcy infections in humans, mosquitoes and monkeys, along with its biological, clinical and drug sensitivity patterns. Knowledge gaps and further studies on Pcy in humans are also discussed. This parasite currently seems to be geographically limited in South-East Asia (SEA) with a global prevalence in human ranging from 0 to 1.4%. The Pcy infections were reported in local SEA populations and European travelers, and range from asymptomatic carriage to mild/moderate attacks with no evidence of pathognomonic clinical and laboratory patterns but with Pcy strain-shaped clinical differences. Geographical distribution and competence of suitable mosquito vectors and non-primate hosts, globalization, climate change, and increased intrusion of humans into the habitat of monkeys are key determinants to emergence of Pcy parasites in humans, along with its expansion outside SEA. Sensitization/information campaigns coupled with training and assessment sessions of microscopists and clinicians on Pcy are greatly needed to improve data on the epidemiology and management of human Pcy infection. There is a need for development of sensitive and specific molecular tools for individual diagnosis and epidemiological studies. The development of safe and efficient anti-hypnozoite drugs is the main therapeutic challenge for controlling human relapsing malaria parasites. Experience gained from P. knowlesi malaria, development of integrated measures and strategies-ideally with components related to human, monkeys, mosquito vectors, and environment-could be very helpful to prevent emergence of Pcy malaria in humans through disruption of transmission chain from monkeys to humans and ultimately contain its expansion in SEA and potential outbreaks in a context of malaria elimination.

Inherited Germline DNA Repair Gene Defects Are Prevalent Among Thai Patients with Myeloid Neoplasms

Certain germline mutations increase the risk of developing myeloid neoplasms (MNs) accompanied by second hit somatic events, such as therapy-related or oxidation-induced DNA damages. Aberrancy in DNA damage response (DDR) pathways leads to genomic instability giving rise to cancer. Previous data showed that the prevalence of pathogenic germline mutations in young adult Caucasian MN patients was 13-19%.1, 2 The most commonly affected pathways were involved in telomere biology and transcription factors, while the defects in DDRs were found in 15-25%. However, data in Asians are limited. In this study, we investigated the prevalence and landscape of germline variants in cancer predisposition genes in a cohort of Thai patients diagnosed with MNs. Targeted next generation sequencing of 23 germline predisposition genes was performed using the SureSelect custom kit and the Illumina HiSeq 2500 system. The total of 127 unselected adult (> 15 years old) patients from 3 medical centers comprising MDS (66%), MDS/MPN (14%) secondary AML (sAML, 20%) were enrolled. The median age was 66 years old (range 16-93) and 50% were male. Variants reported in COSMIC, the frequency of higher than 0.01% in the Genome Aggregation Database (gnomAD) or Thai exome database (consisted of 1084 Thai exome controls) and variant allelic frequency of less than 30% were excluded. New or exceeding rare nonsense variants or indels, as well as missense variants predicted to be deleterious by at least 4/6 in silico software, were included. The variants were classified according to American College of Medical Genetics (ACMG) classification. 14pathogenic and likely pathogenic germline variants were identified in 15 patients (15/127; 12%). One patient had 2 variants including heterozygous CEBPAP75fs and MSH2A604G. Of the 16 variants, there were 8 (50%) missense, 7 (44%) frameshift, and 1 (6%) nonsense, with a median VAF of 51%, ranging 36-83%. The variants affected the DDR pathway (8/16; 50%), transcriptional regulation pathway (4/16; 25%) and signal transduction pathway (2/16; 13%). Two variants were recurrent i.e.,FANCAAla1219GlyfsTer59 and BRCA2Glu626delinsAspPro and the others were identified in BRCA1/2, MSH2, MSH6, GATA2, CEBPA, DDX41, CBL and NF1. The median age of patients harboring germline variants was younger (58 vs. 66 years old) than those who did not. Half of the cases (6/12) were characterized by normal cytogenetics without enrichment of -7 or complex karyotype, comparable to patients with no germline variants. Of note, 28% (4/14) patients had previous history of gastrointestinal stromal tumor, Graves’ disease, Immune thrombocytopenia, and aplastic anemia (FANCA mutation) for years before MNs were diagnosed. None of the patients reported family history of hematological malignancies. In conclusion, the prevalence of germline predisposition to MNs in Southeast Asian populations is as high as in Caucasians and the identified variants are more commonly involved in the DDR pathway. The defects in the DDR pathway suggested an important role of genomic instability in leukemogenesis. This subset of patients should preferably receive non-cytotoxic treatments to avoid oxidative damages that possibly lead to further clonal evolution. ReferencesKeel SB, Scott A, Sanchez-Bonilla M, Ho PA, Gulsuner S, Pritchard CC, et al. Genetic features of myelodysplastic syndrome and aplastic anemia in pediatric and young adult patients. Haematologica 2016 Nov; 101(11): 1343-1350. Feurstein S, Churpek JE, Walsh T, Keel S, Hakkarainen M, Schroeder T, et al. Germline variants drive myelodysplastic syndrome in young adults. Leukemia 2021 2021/08/01; 35(8): 2439-2444.

Reviewing the epidemiology of head and neck cancer: definitions, trends and risk factors

Introduction Head and neck cancer appears to be increasing in incidence, with potential changes in aetiology proposed. This paper aims to provide a narrative overview of the epidemiological literature to describe the disease burden and trends in terms of incidence and mortality both in the UK and globally and to review the evidence on current risk factors.Methods A search was performed on multiple databases (PubMed and Epistemonikos), applying filters to identify systematic reviews and meta-analyses which investigated head and neck cancer incidence, mortality and risk factors. International and UK cancer registries and sources were searched for incidence and mortality data.Results Multiple definitions of head and neck cancer are employed in epidemiology. Globally, incidence rates have increased in recent decades, largely driven by oropharyngeal cancer. Mortality rates over the last decade have also started to rise, reflecting the disease incidence and static survival rates. Major risk factors include tobacco smoking alone and in combination with alcohol consumption, betel chewing (particularly in Southeast Asian populations) and the human papillomavirus in oropharyngeal cancer.Conclusions These epidemiological data can inform clinical and preventive service planning for head and neck cancer.

Clinical and molecular characteristics of autosomal recessive congenital ichthyosis in Thailand.

Autosomal recessive congenital ichthyosis (ARCI) is a heterogenous group of rare keratinization disorders. To date, more than 13 causative genes have been identified. However, data on clinical and molecular characteristics including genotype-phenotype correlation are lacking in Thailand. We collected cases diagnosed with non-syndromic ARCI and syndromic recessive congenital ichthyosis at the Institute of Dermatology from 2011 to 2021 and performed genetic testing with next-generation sequencing and assessed clinical details. Baseline demographic data, birth history, family history, skin manifestations at birth, current cutaneous manifestations, comorbidities, and response to treatments were assessed. DNA was screened for mutations using targeted gene sequencing of 45 genes related to congenital ichthyosis. A total of 33 patients were analyzed with an average age of 23.8± 13.9 years. Congenital ichthyosiform erythroderma (CIE) was most common (60.6%), followed by lamellar ichthyosis (18.2%), self-improving congenital ichthyosis (6.1%), Netherton syndrome (6.1%), ichthyosis prematurity syndrome (3%), Sjögren-Larsson syndrome (3%) and bathing suit ichthyosis (3%). Eight genes were found with pathogenic variants in our cohort as follows: ABCA12 42.4% (14/33), NIPAL4 24.2% (8/33), TGM1 15.2% (5/33), SPINK5 6.1% (2/33), ALDH3A2 3% (1/33), SLC27A4 3% (1/33), CYP4F22 3% (1/33), and ST14 3% (1/33). Clinically, 79% of patients with ABCA12 pathogenic variants in this study had CIE, 79% of w had novel biallelic pathogenic compound heterozygous variants, whereas 21% had homozygous missense variants. This is the first study to describe clinical and molecular findings of ARCI in a cohort from Thailand. Our findings demonstrate the clinical spectrum of the diseases and expand the molecular findings in a Southeast Asian population.

Genetic diversity in the transmission-blocking vaccine candidate Plasmodium vivax gametocyte protein Pvs230 from the China–Myanmar border area and central Myanmar

BackgroundSexual stage surface antigens are potential targets of transmission-blocking vaccines (TBVs). The gametocyte and gamete surface antigen P230, a leading TBV candidate, is critical for red blood cell binding during exflagellation and subsequent oocyst development. Here, the genetic diversity of Pvs230 was studied in Plasmodium vivax parasite isolates from the China–Myanmar border (CMB) and central Myanmar.MethodsPlasmodium vivax isolates were collected in clinics from malaria-endemic areas of the CMB (143 samples) and Myanmar (23 samples). The interspecies variable part (IVP, nucleotides 1–807) and interspecies conserved part (ICP, 808–2862) of Pvs230 were amplified by PCR and sequenced. Molecular evolution studies were conducted to evaluate the genetic diversity, signature of selection, population differentiation, haplotype network, and population structure of the study parasite populations and publicly available Pvs230 sequences from six global P. vivax populations.ResultsLimited genetic diversity was observed for the CMB (π = 0.002) and Myanmar (π = 0.001) isolates. Most amino acid substitutions were located in the IVP and cysteine-rich domain of Pvs230. Evidence of positive selection was observed for IVP and purifying selection for ICP. Codon-based tests identified specific codons under natural selection in both IVP and ICP. The fixation index (FST) showed low genetic differentiation between East and Southeast Asian populations, with FST ranging from 0.018 to 0.119. The highest FST value (FST = 0.503) was detected between the Turkey and Papua New Guinea populations. A total of 92 haplotypes were identified in global isolates, with the major haplotypes 2 and 9 being the most abundant and circulating in East and Southeast Asia populations. Several detected non-synonymous substitutions were mapped in the predicted structure and B-cell epitopes of Pvs230.ConclusionsWe detected low levels of genetic diversity of Pvs230 in global P. vivax populations. Geographically specific haplotypes were identified for Pvs230. Some mutations are located within a potential B-cell epitope region and need to be considered in future TBV designs.Graphical

Genome-centric analysis of short and long read metagenomes reveals uncharacterized microbiome diversity in Southeast Asians

Despite extensive efforts to address it, the vastness of uncharacterized ‘dark matter’ microbial genetic diversity can impact short-read sequencing based metagenomic studies. Population-specific biases in genomic reference databases can further compound this problem. Leveraging advances in hybrid assembly (using short and long reads) and Hi-C technologies in a cross-sectional survey, we deeply characterized 109 gut microbiomes from three ethnicities in Singapore to comprehensively reconstruct 4497 medium and high-quality metagenome assembled genomes, 1708 of which were missing in short-read only analysis and with >28× N50 improvement. Species-level clustering identified 70 (>10% of total) novel gut species out of 685, improved reference genomes for 363 species (53% of total), and discovered 3413 strains unique to these populations. Among the top 10 most abundant gut bacteria in our study, one of the species and >80% of strains were unrepresented in existing databases. Annotation of biosynthetic gene clusters (BGCs) uncovered more than 27,000 BGCs with a large fraction (36–88%) unrepresented in current databases, and with several unique clusters predicted to produce bacteriocins that could significantly alter microbiome community structure. These results reveal significant uncharacterized gut microbial diversity in Southeast Asian populations and highlight the utility of hybrid metagenomic references for bioprospecting and disease-focused studies.

Taxonomic revaluation of the Ahaetulla prasina (H. Boie in F. Boie, 1827) complex from Northeast India: resurrection and redescription of Ahaetulla flavescens (Wall, 1910) (Reptilia: Serpentes: Colubridae)

The taxonomic status of the nominal taxon Dryophis prasinus flavescens Wall, 1910 is reevaluated herein. Based on molecular data generated from fresh collections of Ahaetulla prasina (H. Boie in F. Boie, 1827) auctorum from Northeast India and, additionally, morphological data from museum specimens originating from the same areas, we resurrect this taxon as Ahaetulla flavescens (Wall, 1910) comb. nov. We clarify the status, identity and locations of its type specimens, rediscover, redescribe and illustrate those specimens and also designate a lectotype in order to effect a proper taxonomic redefinition of this nominal taxon. We provide further details on the morphology and diagnosis of this species and elucidate its phylogenetic position. We also provide a summary of the natural history and distribution of this species. Adding to the known cryptic diversity and genetic divergence within Southeast Asian populations, this work also hints at the need for a taxonomic revision of the A. prasina complex. This work complements a previous study on the A. prasina complex focusing on populations in Indonesia. Taken together, these two studies represent phylogenetic reconstructions from different populations of the A. prasina complex across its distribution range, on the Asian mainland and the surrounding islands.

Seasonal flight and genetic distinction among Xylosandrus crassiusculus populations invasive in Australia

ABSTRACT Xylosandrus crassiusculus is an invasive Asian-origin ambrosia beetle that has spread across many regions of the world, including first records in Queensland, Australia, in 2011 and New Zealand in 2019. To determine the seasonal flight activity of this species in Australia, panel traps using quercivorol + ethanol lures were placed at three study sites in New South Wales. This trapping yielded 1173 beetles, consisting of 21 species from three tribes (Xyleborini, Cryphalini and Hylurgini). Xylosandrus crassiusculus contributed almost half the total number of beetles captured over a period of 12 months, mainly driven by catches at one site. The trapping showed a seasonal peak of X. crassiusculus in late March and early April. The genetic relationships between the Australian and New Zealand specimens of X. crassiusculus were compared with other populations across the world. Phylogenetic analysis of the Australian X. crassiusculus populations showed that the beetle population in Queensland was similar to those found in New Zealand and countries in the Americas (Clade I), while the New South Wales population was closely related to Southeast Asian populations (Clade II). This divergence of genetic populations in Australia infers independent introductions of X. crassiusculus into Australia.

Korean Leopard Cat (Prionailurus bengalensis) population with low genetic diversity is distinct from Southeast Asian populations

Effective conservation strategy for a species can be established based on population differentiation patterns. The results of population genetic analyses have been useful in the decision of ESUs and MUs to maintain evolutionary potential and the fitness of populations. To provide a basis for establishing a conservation unit for the leopard cats (Prionailurus bengalensis), we analyzed their mtDNA cytb gene sequences from the Korean populations and compared them with those in other Asian leopard cats' populations. The nucleotide diversity of the Korean population was lowest among the all Asian populations. Analyses of the haplotypes, phylogenetic tree, AMOVA, and migration rate showed that the Northeast Asian population including the Korean population is distinct from the Southeast Asian population, moreover, the divergence time between the Northeast and the Southeast Asian populations was sufficiently long for differentiation to occur; therefore, it would be reasonable to manage the Northeast Asian population as an independent conservation unit and introducing species to Korea from Southeast Asia should be avoided. In contrast, the differentiation within Northeast Asia was not clear. Additional studies based on a greater number of animals in Northeast Asia around Korea will be needed to secure sources of genetic diversity to rescue the Korean leopard cat.

Inference of population structure and admixture proportion from Y chromosomal data of Chinese population.

In the past two decades, Y chromosome data has been generated for human population genetic studies. These Y chromosome datasets were produced with various testing methods and markers, thus difficult to combine them for a comprehensive analysis. In this study, we combine four human Y chromosomal datasets of Han, Tibetan, Hui, and Li ethnic groups. The dataset contains 27 microsatellites and 137 single nucleotide polymorphisms these populations share in common. We assembled a single dataset containing 2439 individuals from 25 nationwide populations in China. A systematic analysis of genetic distance and clustering was performed. To determine the gene flow of the studied population with worldwide populations, we modeled the ancestry informative markers. The reference panel was regarded as a mixture of South Asian (SAS), East Asian (EAS), European (EUR), African (AFR), and American (AMR) populations from 1000 Genomes data of Y chromosome using nonlinear data-fitting. We then calculated the admixture proportion of these four studied populations with 26 worldwide populations. The results showed that the Han and Hui have great genetic affinity, and Hui is the most admixed ethnic group, with 61.53% EAS, 34.65% SAS, 1.91% AFR, 1.56% AMR, and 0.04% EUR ancestry component (the AMR is highly admixed and thus should be ignored). All the other three ethnic groups contained more than 97% EAS ancestry component. The Li is the least admixed population in this study. The combined dataset in this study is the largest of this kind reported to date and proposes reference population data for use in future paternal genetic studies and forensic genealogical identification.

Characteristics of bisphosphonate and non-bisphosphonate related atypical femoral fracture in a South East Asian population - Secondary analysis.

Studies have found that not all atypical femoral fractures (AFF) are associated with bisphosphonate (BP) use. There are limited data on AFF in non-BP patients. In this study, we characterise factors associated with BP and non-BP related AFF and its mortality in a single centre in Singapore. We conducted a cohort study of subjects above 50years old admitted to Changi General Hospital (CGH), Singapore with fragility subtrochanteric and femoral fractures from 2009 to 2015. Using the ASBMR 2014 criteria fractures are classified into atypical and typical femoral fractures. CGH uses a nationalised electronic health record that allows review of information on patient's demographics, clinical history and previous investigations. Mortality was assessed as of 31st December 2019. Between 2009 and 2015, there were 3097 hip fractures, of which 393 were subtrochanteric and femoral fractures and 69 were classified as AFF by ASBMR 2014 criteria. 35 of AFF occurred in BP exposed and 34 occurred in non-BP exposed patients. There were no significant demographic differences in patients with BP and non-BP related AFF. There were also similar incidences of type 2 diabetes, rheumatoid arthritis and glucocorticoid use. Notably, there were a higher percentage of previous fragility fractures (35.3% vs 9.4%) in BP related AFF. Time to healing of fracture was slightly longer in BP related AFF at median (3months vs 2month, p=0.02), however there were no differences in incidence of delayed healing. Mortality between BP and non-BP related AFF were similar. In a South East Asian population in Singapore, 47.8% of AFF were found to be non-BP related. We found no major demographic and clinical differences between BP and non-BP related AFF. Mortality between BP and non-BP related AFF was similar. Further studies are needed to better understand the optimal treatment of osteoporosis in AFF prone patients in the Asian population.

Diagnostic evaluation of syncope in a tertiary hospital in Metro Manila: a retrospective study

Background: Diagnostic evaluation of syncope is imperative to prevent disability, injury and sudden cardiac death. Work-ups and approach may differ due to geographical factors and the clinical setting where the patient is being managed. This study aims to determine the incidence and evaluation practices for syncope in a single private tertiary center in the Philippines. Methods: A 5-year retrospective study was done wherein records of patients admitted for loss of consciousness were reviewed on domains regarding initial evaluation, specialty referrals, ancillary procedures requested and final diagnosis upon discharge. Results: A total of 572 patients were included. The majority (93%) was referred to cardiology and/or neurology services. Aside from electrocardiogram (ECG), other most common work-ups requested were 2D echocardiogram, brain imaging via Magnetic Resonance Imaging (MRI) or Computed Tomography (CT) scan, electroencephalogram (EEG) and 24-hour Holter monitoring- all of which has a low diagnostic yield (≤ 5%). The most common cause of syncope was neurally-mediated syncope (56%), followed by cardiac syncope (18%), orthostatic hypotension (10%), syncope mimics (7.3%), unspecified cause (7%) and psychogenic cause (1.5%). Conclusion: The incidences of syncope types in this southeast Asian population is consistent with previous findings from Western and other Asian countries. The low percent yield of additional diagnostic modalities to syncope work ups strengthens recommendations for a focused initial evaluation (pertinent history-taking, physical examination, electrocardiogram) to reduce unnecessary tests and exhaustion of resources in concordance with the latest international guidelines.