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Identification and characterization of human serum alpha2-HS glycoprotein as a jacalin-bound protein

To WY, Leung JC, Lai KN

Biochim. Biophys. Acta, 1995 May 18;1249(1):58-64.
PMID: 7766684

We recently adopted immobilized jacalin as an affinity adsorbent to purify human serum IgA for laboratory study. In the course of our investigation, we detected a serum protein that co-eluted with IgA from jacalin-agarose affinity column. It constituted in significant quantity (24.0 +/- 0.9%, n = 30) of total jacalin-bound protein (JBP) and the yield was equivalent to 0.4 +/- 0.1 mg per ml serum. The molecular mass of this protein was 55 kDa with electromobility in the alpha 2 region as demonstrated by SDS-PAGE and immunoelectrophoresis. N-terminal microsequencing of this 55 kDa protein revealed that it is human alpha 2-HS glycoprotein (alpha 2HSG). The molecular interaction of alpha 2HSG with jacalin was characterized by competitive ELISA: human serum IgA, human colostrum secretory IgA (sIgA), and monosaccharides including D-galactose and melibiose exhibited strong inhibitory effect on its binding to jacalin. Accordingly, we propose that human alpha 2HSG binds in a similar manner as that of the bovine fetuin to jacalin. In addition, alpha 2HSG displays similar binding property to jacalin from different geographic area (India and Malaysia) and from different laboratory preparations (Sigma, Pierce and 'homemade' jacalin).
Fulltext Seroprevalence of varicella-zoster virus in five US-bound refugee populations

Leung J, Lopez A, Mitchell T, Weinberg M, Lee D, Thieme M, et al.

J Immigr Minor Health, 2015 Feb;17(1):310-3.
PMID: 24271111 DOI: 10.1007/s10903-013-9946-x

Little is known about varicella-zoster virus (VZV) susceptibility in US-bound refugee populations, although published data suggest that VZV seroprevalence in these refugee populations may be lower than US populations. We describe VZV seroprevalence in five US-bound refugee groups: (1) Bhutanese in Nepal, (2) Burmese on the Thailand-Burma (Myanmar) border, (3) Burmese in Malaysia, (4) Iraqi in Jordan, and (5) Somali in Kenya. Sera were tested for presence of VZV IgG antibodies among adults aged 18-45 years. Overall VZV seroprevalence was 97% across all refugee groups. VZV seroprevalence was also high across all age groups, with seroprevalence ranging from 92-100% for 18-26 year-olds depending on refugee group and 93-100% for 27-45 year-olds. VZV seroprevalence was unexpectedly high in these five US-bound refugee groups, though may not reflect seroprevalence in other refugee groups. Additional studies are needed to better understand VZV seroprevalence in refugee populations over time and by region.
Perceived Loneliness, Peer, and Parental Relationship With Smoking: A Cross-Sectional Analysis of Adolescents Across South-East Asia

McClure-Thomas C, Lim C, Sebayang S, Fausiah F, Gouda H, Leung J

Asia Pac J Public Health, 2022 Nov;34(8):770-777.
PMID: 35880310 DOI: 10.1177/10105395221115220

Tobacco use among youth in the South-East Asian region is quite prevalent. This study aims to examine if psychosocial factors (perceived loneliness, peer, and parental relationships) were associated with adolescent smoking, and whether the effects were different according to sex and age. Data came from the Global School-based Student Health Surveys collected between 2012 and 2015 in Brunei, Cambodia, Indonesia, Laos, Malaysia, Philippines, Thailand, Timor-Leste, and Vietnam. 64 578 (males = 48.5%) adolescents aged 13-18 completed the survey. Prevalence of past-month cigarette use was 10.6%. Adolescent smoking was associated with loneliness (OR = 1.75), lack of close friends (OR = 1.43), and lack of parental understanding (OR = 1.35). There was significant interactions between sex with loneliness, close friends, and parental understanding (p < .001). Interactions indicated having no close friends is associated with smoking and is stronger for females than males. Conversely, loneliness was associated with smoking more strongly in males than females. Results indicate that psychosocial factors are linked to adolescent smoking in South-East Asia, suggesting a further need for research on the relation of psychosocial factors with smoking, and their underlying factors.
The role, responsibilities and status of the clinical medical physicist in AFOMP

Ng KH, Cheung KY, Hu YM, Inamura K, Kim HJ, Krisanachinda A, et al.

Australas Phys Eng Sci Med, 2009 Dec;32(4):175-9.
PMID: 20169835

This document is the first of a series of policy statements being issued by the Asia-Oceania Federation of Organizations for Medical Physics (AFOMP). The document was developed by the AFOMP Professional Development Committee (PDC) and was endorsed for official release by AFOMP Council in 2006. The main purpose of the document was to give guidance to AFOMP member organizations on the role and responsibilities of clinical medical physicists. A definition of clinical medical physicist has also been provided. This document discusses the following topics: professional aspects of education and training; responsibilities of the clinical medical physicist; status and organization of the clinical medical physics service and the need for clinical medical physics service.
In(x)Ga(1-x)As nanowires with uniform composition, pure wurtzite crystal phase and taper-free morphology

Ameruddin AS, Fonseka HA, Caroff P, Wong-Leung J, Op het Veld RL, Boland JL, et al.

Nanotechnology, 2015 May 22;26(20):205604.
PMID: 25927420 DOI: 10.1088/0957-4484/26/20/205604

Obtaining compositional homogeneity without compromising morphological or structural quality is one of the biggest challenges in growing ternary alloy compound semiconductor nanowires. Here we report growth of Au-seeded InxGa1-xAs nanowires via metal-organic vapour phase epitaxy with uniform composition, morphology and pure wurtzite (WZ) crystal phase by carefully optimizing growth temperature and V/III ratio. We find that high growth temperatures allow the InxGa1-xAs composition to be more uniform by suppressing the formation of typically observed spontaneous In-rich shells. A low V/III ratio results in the growth of pure WZ phase InxGa1-xAs nanowires with uniform composition and morphology while a high V/III ratio allows pure zinc-blende (ZB) phase to form. Ga incorporation is found to be dependent on the crystal phase favouring higher Ga concentration in ZB phase compared to the WZ phase. Tapering is also found to be more prominent in defective nanowires hence it is critical to maintain the highest crystal structure purity in order to minimize tapering and inhomogeneity. The InP capped pure WZ In0.65Ga0.35As core-shell nanowire heterostructures show 1.54 μm photoluminescence, close to the technologically important optical fibre telecommunication wavelength, which is promising for application in photodetectors and nanoscale lasers.
Fulltext Diseases, Injuries, and Risk Factors in Child and Adolescent Health, 1990 to 2017: Findings From the Global Burden of Diseases, Injuries, and Risk Factors 2017 Study

GBD 2017 Child and Adolescent Health Collaborators, Reiner RC, Olsen HE, Ikeda CT, Echko MM, Ballestreros KE, et al.

JAMA Pediatr, 2019 06 01;173(6):e190337.
PMID: 31034019 DOI: 10.1001/jamapediatrics.2019.0337

Importance: Understanding causes and correlates of health loss among children and adolescents can identify areas of success, stagnation, and emerging threats and thereby facilitate effective improvement strategies.
Objective: To estimate mortality and morbidity in children and adolescents from 1990 to 2017 by age and sex in 195 countries and territories.
Design, Setting, and Participants: This study examined levels, trends, and spatiotemporal patterns of cause-specific mortality and nonfatal health outcomes using standardized approaches to data processing and statistical analysis. It also describes epidemiologic transitions by evaluating historical associations between disease indicators and the Socio-Demographic Index (SDI), a composite indicator of income, educational attainment, and fertility. Data collected from 1990 to 2017 on children and adolescents from birth through 19 years of age in 195 countries and territories were assessed. Data analysis occurred from January 2018 to August 2018.
Exposures: Being under the age of 20 years between 1990 and 2017.
Main Outcomes and Measures: Death and disability. All-cause and cause-specific deaths, disability-adjusted life years, years of life lost, and years of life lived with disability.
Results: Child and adolescent deaths decreased 51.7% from 13.77 million (95% uncertainty interval [UI], 13.60-13.93 million) in 1990 to 6.64 million (95% UI, 6.44-6.87 million) in 2017, but in 2017, aggregate disability increased 4.7% to a total of 145 million (95% UI, 107-190 million) years lived with disability globally. Progress was uneven, and inequity increased, with low-SDI and low-middle-SDI locations experiencing 82.2% (95% UI, 81.6%-82.9%) of deaths, up from 70.9% (95% UI, 70.4%-71.4%) in 1990. The leading disaggregated causes of disability-adjusted life years in 2017 in the low-SDI quintile were neonatal disorders, lower respiratory infections, diarrhea, malaria, and congenital birth defects, whereas neonatal disorders, congenital birth defects, headache, dermatitis, and anxiety were highest-ranked in the high-SDI quintile.
Conclusions and Relevance: Mortality reductions over this 27-year period mean that children are more likely than ever to reach their 20th birthdays. The concomitant expansion of nonfatal health loss and epidemiological transition in children and adolescents, especially in low-SDI and middle-SDI countries, has the potential to increase already overburdened health systems, will affect the human capital potential of societies, and may influence the trajectory of socioeconomic development. Continued monitoring of child and adolescent health loss is crucial to sustain the progress of the past 27 years.
Fulltext Child and Adolescent Health From 1990 to 2015: Findings From the Global Burden of Diseases, Injuries, and Risk Factors 2015 Study

Global Burden of Disease Child and Adolescent Health Collaboration, Kassebaum N, Kyu HH, Zoeckler L, Olsen HE, Thomas K, et al.

JAMA Pediatr, 2017 Jun 01;171(6):573-592.
PMID: 28384795 DOI: 10.1001/jamapediatrics.2017.0250

IMPORTANCE: Comprehensive and timely monitoring of disease burden in all age groups, including children and adolescents, is essential for improving population health.
OBJECTIVE: To quantify and describe levels and trends of mortality and nonfatal health outcomes among children and adolescents from 1990 to 2015 to provide a framework for policy discussion.
EVIDENCE REVIEW: Cause-specific mortality and nonfatal health outcomes were analyzed for 195 countries and territories by age group, sex, and year from 1990 to 2015 using standardized approaches for data processing and statistical modeling, with subsequent analysis of the findings to describe levels and trends across geography and time among children and adolescents 19 years or younger. A composite indicator of income, education, and fertility was developed (Socio-demographic Index [SDI]) for each geographic unit and year, which evaluates the historical association between SDI and health loss.
FINDINGS: Global child and adolescent mortality decreased from 14.18 million (95% uncertainty interval [UI], 14.09 million to 14.28 million) deaths in 1990 to 7.26 million (95% UI, 7.14 million to 7.39 million) deaths in 2015, but progress has been unevenly distributed. Countries with a lower SDI had a larger proportion of mortality burden (75%) in 2015 than was the case in 1990 (61%). Most deaths in 2015 occurred in South Asia and sub-Saharan Africa. Global trends were driven by reductions in mortality owing to infectious, nutritional, and neonatal disorders, which in the aggregate led to a relative increase in the importance of noncommunicable diseases and injuries in explaining global disease burden. The absolute burden of disability in children and adolescents increased 4.3% (95% UI, 3.1%-5.6%) from 1990 to 2015, with much of the increase owing to population growth and improved survival for children and adolescents to older ages. Other than infectious conditions, many top causes of disability are associated with long-term sequelae of conditions present at birth (eg, neonatal disorders, congenital birth defects, and hemoglobinopathies) and complications of a variety of infections and nutritional deficiencies. Anemia, developmental intellectual disability, hearing loss, epilepsy, and vision loss are important contributors to childhood disability that can arise from multiple causes. Maternal and reproductive health remains a key cause of disease burden in adolescent females, especially in lower-SDI countries. In low-SDI countries, mortality is the primary driver of health loss for children and adolescents, whereas disability predominates in higher-SDI locations; the specific pattern of epidemiological transition varies across diseases and injuries.
CONCLUSIONS AND RELEVANCE: Consistent international attention and investment have led to sustained improvements in causes of health loss among children and adolescents in many countries, although progress has been uneven. The persistence of infectious diseases in some countries, coupled with ongoing epidemiologic transition to injuries and noncommunicable diseases, require all countries to carefully evaluate and implement appropriate strategies to maximize the health of their children and adolescents and for the international community to carefully consider which elements of child and adolescent health should be monitored.