Background: Chloroquine combined with primaquine has been the recommended antimalarial treatment of Plasmodium vivax malaria infections for six decades but the efficacy of this treatment regimen is threatened by chloroquine resistance (CQR). Single nucleotide polymorphisms (SNPs) in the multidrug resistance gene, Pvmdr1 are putative determinants of CQR but the extent of their emergence at population level remains to be explored.
Objective: In this study we describe the prevalence of SNPs in the Pvmdr1 among samples collected in seven P. vivax endemic countries and we looked for molecular evidence of drug selection by characterising polymorphism at microsatellite (MS) loci flanking the Pvmdr1 gene.
Methods: We examined the prevalence of SNPs in the Pvmdr1 gene among 267 samples collected from Pakistan, Afghanistan, Sri Lanka, Nepal, Sudan, São Tomé and Ecuador. We measured and diversity in four microsatellite (MS) markers flanking the Pvmdr1 gene to look evidence of selection on mutant alleles.
Results: SNP polymorphism in the Pvmdr1 gene was largely confined to codons T958M, Y976F and F1076L. Only 2.4% of samples were wildtype at all three codons (TYF, n = 5), 13.3% (n = 28) of the samples were single mutant MYF, 63.0% of samples (n = 133) were double mutant MYL, and 21.3% (n = 45) were triple mutant MFL. Clear geographic differences in the prevalence of these Pvmdr mutation combinations were observed. Significant linkage disequilibrium (LD) between Pvmdr1 and MS alleles was found in populations sampled in Ecuador, Nepal and Sri Lanka, while significant LD between Pvmdr1 and the combined 4 MS locus haplotype was only seen in Ecuador and Sri Lanka. When combining the 5 loci, high level diversity, measured as expected heterozygosity (He), was seen in the complete sample set (He = 0.99), while He estimates for individual loci ranged from 0.00-0.93. Although Pvmdr1 haplotypes were not consistently associated with specific flanking MS alleles, there was significant differentiation between geographic sites which could indicate directional selection through local drug pressure.
Conclusions: Our observations suggest that Pvmdr1 mutations emerged independently on multiple occasions even within the same population. In Sri Lanka population analysis at multiple sites showed evidence of local selection and geographical dispersal of Pvmdr1 mutations between sites.
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http://dx.doi.org/10.1371/journal.pntd.0004196 | DOI Listing |
BMC Pregnancy Childbirth
January 2025
Centre for Healthcare Transformation, School of Public Health and Social Work, Faculty of Health, Queensland University of Technology, Kelvin Grove, QLD, 4059, Australia.
Background: In Sri Lanka, there is some evidence that the likelihood of breastfeeding initiation varies by exposure to Baby-Friendly Hospital Initiative [BFHI]-compliant care and mode of birth. Globally, there is some evidence that exposure to mother-baby skin-to-skin contact (BFHI Step 4) is lower in caesarean section births. Therefore, we aimed to determine how breastfeeding initiation varies by mode of birth in Sri Lanka, and the extent to which women's exposure to BFHI practices explains any associations found.
View Article and Find Full Text PDFArch Dermatol Res
January 2025
Faculty of Medicine, University of Ruhuna, Matara, Sri Lanka.
Psoriasis is associated with psychological distress among the affected due to unsightly skin lesions, chronicity and the cultural and social stigma linked with the disease. The pathophysiological link between psoriasis and depression creates a vicious cycle in the skin and brain axis. This study evaluates the psychological comorbidity of patients with chronic plaque psoriasis (CPP).
View Article and Find Full Text PDFBMJ Open
January 2025
Department of Medicine, University of Kelaniya Faculty of Medicine, Ragama, Sri Lanka.
Introduction: Models derived from non-Sri Lankan cohorts are used for cardiovascular (CV) risk stratification of Sri Lankans.
Objective: To develop a CV risk prediction model using machine learning (ML) based on data from a Sri Lankan cohort followed up for 10 years, and to compare the predictions with WHO risk charts.
Design: Cohort study.
Aust Crit Care
January 2025
School of Nursing and Midwifery, Griffith University, Queensland, Australia; NHMRC CRE in Wiser Wound Care, Griffith University, Queensland, Australia.
Background: Communication boards are a low-technology tool used to facilitate interactions with mechanically ventilated patients in intensive care units (ICUs). Research on the acceptability of communication boards in resource-limited intensive care settings is lacking.
Aim: The aim of this study was to assess patients' and nurses' experienced acceptability of implementing a communication board in Sri Lankan ICUs.
A comprehensive revision is presented of the Oriental and Australasian diving beetle genus Sharp, 1882 (Coleoptera: Dytiscidae: Dytiscinae: Aciliini) and seven junior subjective synonyms are proposed. Balfour-Browne, 1939, is a junior subjective synonym of Heller, 1934; Vazirani, 1969, of (Crotch, 1872); Blanchard, 1843, of (Aubé, 1838); and Heller, 1934, , Sharp, 1882, , and Satô, 1978, of (Wehncke, 1876). Finally, Anand et al.
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