Exploring young people's attitudes to HIV prevention medication (PrEP) in England: a qualitative study

INTRODUCTION

Young people aged 18-24 years old are a key demographic target for eliminating HIV transmission globally. Pre-exposure prophylaxis (PrEP), a prevention medication, reduces HIV transmission. Despite good uptake by gay and bisexual men who have sex with men, hesitancy to use PrEP has been observed in other groups, such as young people and people from ethnic minority backgrounds. The aim of this study was to explore young people's perceptions and attitudes to using PrEP.

DESIGN

A qualitative transcendental phenomenological design was used.

PARTICIPANTS AND SETTING

A convenience sample of 24 young people aged between 18 and 24 years was recruited from England.

METHODS

Semistructured interviews and graphical elicitation were used to collect data including questions about current experiences of HIV care, awareness of using PrEP and decision-making about accessing PrEP. Thematic and visual analyses were used to identify findings.

RESULTS

Young people had good levels of knowledge about HIV but poor understanding of using PrEP. In this information vacuum, negative stigma and stereotypes about HIV and homosexuality were transferred to using PrEP, which were reinforced by cultural norms portrayed on social media, television and film-such as an association between using PrEP and being a promiscuous, white, gay male. In addition, young people from ethnic minority communities appeared to have negative attitudes to PrEP use, compared with ethnic majority counterparts. This meant these young people in our study were unable to make decisions about when and how to use PrEP.

CONCLUSION

Findings indicate an information vacuum for young people regarding PrEP. A strength of the study is that theoretical data saturation was reached. A limitation of the study is participants were largely from Northern England, which has low prevalence of HIV. Further work is required to explore the information needs of young people in relation to PrEP.

Plant-derived compounds as potential leads for new drug development targeting COVID-19

COVID-19, which was first identified in 2019 in Wuhan, China, is a respiratory illness caused by a virus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although some patients infected with COVID-19 can remain asymptomatic, most experience a range of symptoms that can be mild to severe. Common symptoms include fever, cough, shortness of breath, fatigue, loss of taste or smell and muscle aches. In severe cases, complications can arise including pneumonia, acute respiratory distress syndrome, organ failure and even death, particularly in older adults or individuals with underlying health conditions. Treatments for COVID-19 include remdesivir, which has been authorised for emergency use in some countries, and dexamethasone, a corticosteroid used to reduce inflammation in severe cases. Biological drugs including monoclonal antibodies, such as casirivimab and imdevimab, have also been authorised for emergency use in certain situations. While these treatments have improved the outcome for many patients, there is still an urgent need for new treatments. Medicinal plants have long served as a valuable source of new drug leads and may serve as a valuable resource in the development of COVID-19 treatments due to their broad-spectrum antiviral activity. To date, various medicinal plant extracts have been studied for their cellular and molecular interactions, with some demonstrating anti-SARS-CoV-2 activity in vitro. This review explores the evaluation and potential therapeutic applications of these plants against SARS-CoV-2. This review summarises the latest evidence on the activity of different plant extracts and their isolated bioactive compounds against SARS-CoV-2, with a focus on the application of plant-derived compounds in animal models and in human studies.

Quantifiable Changes in the Submental Area and Mandible Border After Dual-Modality Treatment With ATX-101 and VYC-20L for Overall Improvement in Jawline Contour

BACKGROUND

A phase 4, prospective, open-label, multicenter study showed that treatment with deoxycholic acid injections (ATX-10) followed by a hyaluronic acid filler (VYC-20L) is safe and effective for reducing submental fullness and improving jawline definition.

OBJECTIVE

To quantify changes in the jawline and submental area using 3-dimensional (3D) photogrammetry and conduct an immunohistochemical analysis of submental tissue.  Methods: Participants received 1 to 6 ATX-101 treatments (8 weeks apart) followed by VYC-20L (optional touch-up after 14 days). Changes from baseline in jawline and submental volumes, submental major and minor strain events, submental skin displacement, and submental angles were quantified using photogrammetry. Submental skin biopsies (N=13) were excised for histologic analysis. Treatment-emergent adverse events (TEAEs) were monitored.

RESULTS

Fifty-three participants were treated. From baseline to the final study visit, the mean volume increased for the jawline and decreased for the submental area. There was a larger percentage change from baseline in the minor versus major strain event, indicating greater skin surface compression than expansion within the submental area. Mean change from baseline in submental skin position indicated superior and posterior movement from a lateral perspective, while the mean submental angle decreased between baseline and exit. Collagen I and III expression significantly increased from baseline (P<0.05). All participants reported at least 1 TEAE; the majority were mild or moderate in severity.

CONCLUSIONS

Dual-modality treatment with ATX-101 and VYC-20L reduces submental fat and improves jawline definition with quantifiable changes in jawline volume, submental volume, strain, skin displacement, and angle, as well as collagen expression. J Drugs Dermatol. 2024;23(1):1325-1331.        doi:10.36849/JDD.7458.

Can We Deliver Person-Centred Obesity Care Across the Globe?

PURPOSE OF REVIEW

This article discusses what person-centred care is; why it is critically important in providing effective care of a chronic, complex disease like obesity; and what can be learnt from international best practice to inform global implementation.

RECENT FINDINGS

There are four key principles to providing person-centred obesity care: providing care that is coordinated, personalised, enabling and delivered with dignity, compassion and respect. The Canadian 5AsT framework provides a co-developed person-centred obesity care approach that addresses complexity and is being tested internationally. Embedding person-centred obesity care across the globe will require a complex system approach to provide a framework for healthcare system redesign, advances in people-driven discovery and advocacy for policy change. Additional training, tools and resources are required to support local implementation, delivery and evaluation. Delivering high-quality, effective person-centred care across the globe will be critical in addressing the current obesity epidemic.

Cosmetic surgery—why training matters

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Categories

Editors-in-Chief Mark Lee and Mark Ashton propose a holistic categorisation system that is more reflective of urgency and less prone to manipulation or ‘turning off’ in times of pressure.

Toolkit for the management of breast implants and the importance of Informed educated consent

Breast implants have had a long and chequered history of periodic regulatory activity and class actions and are associated with significant medium and long term health risks, including the development breast implant associated anaplastic large cell lymphoma (BIA-ALCL).1–3. NSW Health through the Agency of Clinical Innovation has just released a toolkit for the management of breast implants.4 These are the result of collaborative clinical consensus across leaders in plastic and reconstructive surgery, breast surgery and radiology with support from the Surgical Services Taskforce and evidence directorate of the agency. Input was also sought from health consumers to ensure that the language and structure of the information was both comprehensive and accessible to women who were either considering either cosmetic augmentation or reconstruction and/or have breast implants in place.

Antecedents and outcomes of artificial intelligence adoption and application in the workplace: the socio-technical system theory perspective

Purpose

The use of artificial intelligence (AI) in the workplace is on the rise. To help advance research in this area, the authors synthesise the academic research and develop research propositions on the antecedents and consequences of AI adoption and application in the workplace to guide future research. The authors also present AI research in the socio-technical system context to provide a springboard for new research to fill the knowledge gap of the adoption and application of AI in the workplace.

Design/methodology/approach

This paper summarises the existing literature and builds a theoretically grounded conceptual framework on the socio-technical system theory that captures the essence of the impact of AI in the workplace.

Findings

The antecedents of AI adoption and application include personnel subsystem, technical subsystem, organisational structure subsystem and environmental factors. The consequences of AI adoption and application include individual, organisational and employment-related outcomes.

Practical implications

A research agenda is provided to identify and discuss future research that comprises not only insightful theoretical contributions but also practical implications. A greater understanding of AI adoption from socio-technical system perspective will enable managers and practitioners to develop effective AI adoption strategies, enhance employees' work experience and achieve competitive advantage for organisations.

Originality/value

Drawing on the socio-technical system theory, the proposed conceptual framework provides a comprehensive understanding of the antecedents and consequences of AI adoption and application in the work environment. The authors discuss the main contributions to theory and practice, along with potential future research directions of AI in the workplace related to three key themes at the individual, organisational and employment level.

Climate Adaptive Silviculture for the City: Practitioners and Researchers Co-create a Framework for Studying Urban Oak-Dominated Mixed Hardwood Forests

Urban forested natural areas are an important component of the forest and tree canopy in northeastern United States urban areas. Although similar to native forests in surrounding regions in structure, composition, and function, these natural areas are threatened by multiple, co-occurring biological and climate stressors that are exacerbated by the urban environment. Furthermore, forests in cities often lack application of formal silvicultural approaches reliant upon evidence-based applied ecological sciences. These include both urban- and climate-adapted silvicultural techniques to increase the resilience and sustainability of native forests in cities. With this in mind, we convened a group of urban forest practitioners and researchers from along a latitudinal gradient in the northeastern United States to participate in a workshop focused on co-developing long-term, replicated ecological studies that will underlie the basis for potential silvicultural applications to urban forests. In this article we review the process and outcomes of the workshop, including an assessment of forest vulnerability, and adaptive capacity across the region, as well as shared management goals and objectives. We discuss the social and ecological challenges of managing urban oak-dominated mixed hardwood forests relative to non-urban forests and identify potential examples of urban- and climate-adapted silviculture strategies created by practitioners and researchers. In doing so, we highlight the challenges and need for basic and long-term applied ecological research relevant to silvicultural applications in cities.

Suffering in silence

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Drug repurposing: Misconceptions, challenges, and opportunities for academic researchers

[Figure: see text].

Light at the end of the tunnel

It is not hard to list some of the profound effects COVID-19 has had on the specialty of plastic surgery. World-wide many of our colleagues have suffered serious illness and many have died. Even in countries like Australia and New Zealand, relatively spared from the ravages of the disease, we have all had significant disruptions to our lives and practicesLimitations on elective surgery during lockdown, reduced rates of screening for breast cancer and melanoma (Figure 1), consulting with masks—all affect our ability to provide a safe and effective service for our patients. Eminent plastic surgeons choosing to take early retirement is a great loss of institutional memory. Opportunistic governments and administrators taking advantage and using COVID-19 as an excuse to push through ‘urgent’ changes challenge our ability to provide a safe and effective service

COVID-19 testing in outbreak-free care homes: what are the public health benefits?

BACKGROUND

COVID-19 care home outbreaks represent a significant proportion of COVID-19 morbidity and mortality in the UK. National testing initially focused on symptomatic care home residents, before extending to asymptomatic cohorts.

AIM

The aim was to describe the epidemiology and transmission of COVID-19 in outbreak free care homes.

METHODS

A two-point prevalence survey of COVID-19, in 34 Liverpool care homes, was performed in April and May 2020. Changes in prevalence were analysed. Associations between care home characteristics, reported infection, prevention and control interventions, and COVID-19 status were described and analysed.

FINDINGS

No resident developed COVID-19 symptoms during the study. There was no significant difference between: the number of care homes containing at least one test positive resident between the first (17.6%, 95% confidence interval (CI) 6.8-34.5) and second round (14.7%, 95% CI 5.0-31.1) of testing (p>0.99); and the number of residents testing positive between the first (2.1%, 95% CI 1.2-3.4) and second round (1.0%, 95% CI 0.5-2.1) of testing (P=0.11). Care homes providing nursing care (risk ratio (RR) 7.99, 95% CI 1.1-57.3) and employing agency staff (RR 8.4, 95% CI 1.2-60.8) were more likely to contain test positive residents. Closing residents shared space was not associated with residents testing positive (RR 2.63, 95% CI 0.4-18.5).

CONCLUSIONS

Asymptomatic COVID-19 care homes showed no evidence of disease transmission or development of outbreaks; suggesting that current infection prevention and control measures are effective in preventing transmission. Repeat testing at two to three weeks had limited or no public health benefits over regular daily monitoring of staff and residents for symptoms. These results should inform policies calling for regular testing of asymptomatic residents.

Quarantine

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Ikigai: a balanced life in plastic surgery

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Holier than thou: are we all biased?

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Pain management in patients with malignant mesothelioma: challenges and solutions

Malignant pleural mesothelioma (MPM) is an aggressive cancer with a considerable symptom burden and poor prognosis. Focus on maintaining patients’ quality of life and pain control is therefore paramount. Pain management in MPM is complex due to its multifactorial etiology resulting from direct tumor infiltration of the surrounding soft tissue, bone, and encasement of the intercostal nerves. A variety of treatment modalities, including pharmacological and non-pharmacological options, are often required to achieve adequate pain control in this challenging disease. This review article examines the current challenges and solutions available for pain management in MPM.

Devil's advocate

Is our speciality vulnerable to "groupthink"? Probably so. We are a relatively small and cohesive group, from similar backgrounds, who believe in our own inherent morality. It is important to remember that some of the techniques we are using today may be modified or even totally reversed in time and so it is imperative that we, as a specialty, continually reflect on what we do. We must all challenge accepted dogma. We must allow those with dissenting opinions to speak up. Valid advances and new techniques are able to withstand questioning and o win over even the most vocal critics. It is not the act of questioning which is at fault. Indeed, the questioning of new and established surgical dogma is integral to any worthwhile scientific discussion. Hopefully this journal can in some way be our specialty’s advocatus diaboli.

Australasian Journal of Plastic Surgery: first edition

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Australasian Journal of Plastic Surgery: first edition

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SYSTEMS-2: A randomised phase II study of radiotherapy dose escalation for pain control in malignant pleural mesothelioma

SYSTEMS-2 is a randomised study of radiotherapy dose escalation for pain control in 112 patients with malignant pleural mesothelioma (MPM). Standard palliative (20 Gy/5#) or dose escalated treatment (36 Gy/6#) will be delivered using advanced radiotherapy techniques and pain responses will be compared at week 5. Data will guide optimal palliative radiotherapy in MPM.

Computational methods for 2D materials: discovery, property characterization, and application design

The discovery of two-dimensional (2D) materials comes at a time when computational methods are mature and can predict novel 2D materials, characterize their properties, and guide the design of 2D materials for applications. This article reviews the recent progress in computational approaches for 2D materials research. We discuss the computational techniques and provide an overview of the ongoing research in the field. We begin with an overview of known 2D materials, common computational methods, and available cyber infrastructures. We then move onto the discovery of novel 2D materials, discussing the stability criteria for 2D materials, computational methods for structure prediction, and interactions of monolayers with electrochemical and gaseous environments. Next, we describe the computational characterization of the 2D materials' electronic, optical, magnetic, and superconducting properties and the response of the properties under applied mechanical strain and electrical fields. From there, we move on to discuss the structure and properties of defects in 2D materials, and describe methods for 2D materials device simulations. We conclude by providing an outlook on the needs and challenges for future developments in the field of computational research for 2D materials.

Nutrient enrichment effects on mycorrhizal fungi in an Andean tropical montane Forest

Nitrogen (N) and phosphorus (P) deposition are increasing worldwide largely due to increased fertilizer use and fossil fuel combustion. Most work with N and P deposition in natural ecosystems has focused on temperate, highly industrialized, regions. Tropical regions are becoming more developed, releasing large amounts of these nutrients into the atmosphere. Nutrient enrichment in nutrient-poor systems such as tropical montane forest can represent a relatively large shift in nutrient availability, especially for sensitive microorganisms such as arbuscular mycorrhizal fungi (AMF). These symbiotic fungi are particularly critical, given their key role in ecosystem processes affecting plant community structure and function.To better understand the consequences of nutrient deposition in plant communities, a long-term nutrient addition experiment was set up in a tropical montane forest in the Andes of southern Ecuador. In this study, we investigated the impacts of 7 years of elevated N and P on AMF root colonization potential (AMF-RCP) through a greenhouse bait plant method in which we quantified root colonization. We also examined the relationship between AMF-RCP and rarefied tree diversity.After 7 years of nutrient addition, AMF-RCP was negatively correlated with soil P, positively correlated with soil N, and positively correlated with rarefied tree diversity. Our results show that AMF in this tropical montane forest are directly affected by soil N and P concentrations, but may also be indirectly impacted by shifts in rarefied tree diversity. Our research also highlights the need to fully understand the benefits and drawbacks of using different sampling methods (e.g., AMF-RCP versus direct root sampling) to robustly examine AMF-plant interactions in the future.

Development of a Predictive Model for the Long-Term Stability Assessment of Drug-In-Adhesive Transdermal Films Using Polar Pressure-Sensitive Adhesives as Carrier/Matrix

Drug crystallization in transdermal drug delivery systems is a critical quality defect. The impact of drug load and hydration on the physical stability of polar (acrylic) drug-in-adhesive (DIA) films was investigated with the objective to identify predictive formulation parameters with respect to drug solubility and long-term stability. Medicated acrylic films were prepared over a range of drug concentrations below and above saturation solubility and were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, polarized microscopy, and dynamic vapor sorption (DVS) analysis. Physical stability of medicated films was monitored over 4 months under different storage conditions and was dependent on solubility parameters, Gibbs free energy for drug phase transition from the amorphous to the crystalline state, and relative humidity. DVS data, for assessing H-bonding capacity experimentally, were essential to predict physical stability at different humidities and were used together with Gibbs free energy change and the Hoffman equation to develop a new predictive thermodynamic model to estimate drug solubility and stability in DIA films taking into account relative humidity.

Analysis of residual crosslinking agent content in UV cross-linked poly(ethylene oxide) hydrogels for dermatological application by gas chromatography

Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively inert, causing no irritation and allergies. Poly(ethylene oxide) (PEO) hydrogels were prepared using pentaerythritol tetra-acrylate (PETRA) as UV crosslinking agent. A simple, accurate, and robust quantitation method was developed based on gas chromatographic techniques (GC), which is suitable for routine analysis of residual PETRA monomers in these hydrogels. Unreacted PETRA was initially identified using gas chromatography–mass spectrometry (GC–MS). The quantitation of analyte was performed and validated using gas chromatography equipped with a flame ionization detector (GC–FID). A linear relationship was obtained over the range of 0.0002%–0.0450% (m/m) with a correlation coefficient (r²) greater than 0.99. The recovery (>90%), intra-day precision (%RSD <0.67), inter-day precision (%RSD <2.5%), and robustness (%RSD <1.62%) of the method were within the acceptable values. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.0001% (m/m) and 0.0002% (m/m), respectively. This assay provides a simple and quick way of screening for residual acrylate monomer in hydrogels.

Effect of Crosslinking Agent Concentration on the Properties of Unmedicated Hydrogels

Novel polyethylene oxide (PEO) hydrogel films were synthesized via UV crosslinking with varying concentrations of pentaerythritol tetra-acrylate (PETRA) as crosslinking agent. The aim was to study the effects of the crosslinking agent on the material properties of hydrogel films intended for dermatological applications. Fabricated film samples were characterized using swelling studies, scanning electron microscopy, tensile testing and rheometry. Films showed rapid swelling and high elasticity. The increase of PETRA concentration resulted in significant increase in the gel fraction and crosslinking density (ρ_c), while causing a significant decrease in the equilibrium water content (EWC), average molecular weight between crosslinks (M¯c), and mesh size (ζ) of films. From the scanning electron microscopy, cross-linked PEO hydrogel network appeared as cross-linked mesh-like structure with interconnected micropores. Rheological studies showed PEO films required a minimum of 2.5% w/w PETRA to form stable viscoelastic solid gels. Preliminary studies concluded that a minimum of 2.5% w/w PETRA is required to yield films with desirable properties for skin application.

Early soft tissue coverage and negative pressure wound therapy optimises patient outcomes in lower limb trauma

BACKGROUND

The timing of soft tissue reconstruction for severe open lower limb trauma is critical to its successful outcome, particularly in the setting of exposed metalware and pre-existing wound infection. The use of negative pressure wound therapy (NPWT) may allow a delay in soft tissue coverage without adverse effects. This study evaluated the impact of delayed free-flap reconstruction, prolonged metalware exposure, pre-flap wound infection, and the efficacy of NPWT on the success of soft tissue coverage after open lower limb injury.

METHODS

Retrospective review of all free-flap reconstructions for lower limb trauma undertaken at a tertiary trauma centre between June 2002 and July 2009.

RESULTS

103 patients underwent 105 free-flap reconstructions. Compared with patients who were reconstructed within 3 days of injury, the cohort with delayed reconstruction beyond 7 days had significantly increased rates of pre-flap wound infection, flap re-operation, deep metal infection and osteomyelitis. Pre-flap wound infection independently predicted adverse surgical outcomes. In the setting of exposed metalware, free-flap transfer beyond one day significantly increased the flap failure rate. These patients required more surgical procedures and a longer hospital stay. The use of NPWT significantly lowered the rate of flap re-operations and venous thrombosis, but did not allow a delay in reconstruction beyond 7 days from injury without a concomitant rise in skeletal and flap complications.

CONCLUSIONS

Following open lower limb trauma, soft tissue coverage within 3 days of injury and immediately following fracture fixation with exposed metalware minimises pre-flap wound infection and optimises surgical outcomes. NPWT provides effective temporary wound coverage, but does not allow a delay in definitive free-flap reconstruction.

Large de novo deletion of 7p15.1 to 7p12.1 involving the imprinted gene GRB10 associated with a complex phenotype including features of Beckwith Wiedemann syndrome

We present an infant with a de novo cytogenetically visible interstitial deletion of approximately 21.9Mb involving chromosome bands 7p15.1-7p12.1, with the loss of 119 genes confirmed by array CGH. The infant had a ventricular septal defect, hand and skull anomalies, and hyperglycaemia compatible with haploinsufficiency of TBX20, GLI3, and GCK genes, respectively. In addition, the infant had some features reminiscent of Beckwith Wiedemann syndrome including macroglossia, umbilical hernia, and a relatively large birth weight and we speculate that this is due to the deletion of GRB10, an imprinted gene on chromosome 7. This report illustrates how knowledge of genes within a deleted interval facilitates optimal medical management, can explain observed phenotypes, and stimulates research questions.

Determination of eflornithine enantiomers in plasma by precolumn derivatization with o-phthalaldehyde-N-acetyl-L-cysteine and liquid chromatography with UV detection

A bioanalytical method for indirect determination of eflornithine enantiomers in 75 microL human plasma has been developed and validated. L- and D-eflornithine were derivatized with o-phthalaldehyde and N-acetyl-L-cysteine to generate diastereomers which were separated on two serially connected Chromolith Performance columns (RP-18e 100 x 4.6 mm i.d.) by a isocratic flow followed by a gradient flow for elution of endogenous compounds. The diastereomers were detected with UV (340 nm). The between-day precisions for L- and D-eflornithine in plasma were 8.4 and 2.3% at 3 microm, 4.0 and 5.1% at 400 microm, and 2.0 and 3.7% at 1000 microm. The lower limit of quantification was determined to be 1.5 microm, at which precision was 14.9 and 9.9% for L- and D-eflornithine, respectively.

Molecular microbiological characterization of preterm neonates at risk of bronchopulmonary dysplasia

The role of infection in bronchopulmonary dysplasia (BPD) is unknown. We present an observational study of 55 premature infants born weighing less than 1.3 kg within two level III neonatal intensive care units. Endotracheal aspirates (ETA) and nasogastric aspirates (NGA) were studied with denaturing gradient gel electrophoresis (DGGE) profiling to elucidate the total bacterial community, and species-specific PCR was used to detect the presence of Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum. DGGE identified bacterial species in 59% of NGA and ETA samples combined. A diverse range of species were identified including several implicated in preterm labor. Species-specific PCR identified M. hominis in 25% of NGA and 11% of ETA samples. Among the 48 infants surviving up to 36 wk-postconceptual age, ordinal logistic regression showed the odds ratio for BPD or death where Ureaplasma was present/absent as 4.80 (95% CI 1.15-20.13). After adjusting for number of days ventilated, this was reduced to 2.04 (0.41-10.25). These data demonstrate how the combined use of DGGE and species-specific PCR identifies a high exposure in utero and around the time of birth to bacteria that might be causally related to preterm delivery and subsequent lung injury.

Quantification of artemisinin in human plasma using liquid chromatography coupled to tandem mass spectrometry

A liquid chromatographic tandem mass spectroscopy method for the quantification of artemisinin in human heparinised plasma has been developed and validated. The method uses Oasis HLB mu-elution solid phase extraction 96-well plates to facilitate a high throughput of 192 samples a day. Artesunate (internal standard) in a plasma-water solution was added to plasma (50 microL) before solid phase extraction. Artemisinin and its internal standard artesunate were analysed by liquid chromatography and MS/MS detection on a Hypersil Gold C18 (100 mm x 2.1 mm, 5 microm) column using a mobile phase containing acetonitrile-ammonium acetate 10mM pH 3.5 (50:50, v/v) at a flow rate of 0.5 mL/min. The method has been validated according to published FDA guidelines and showed excellent performance. The within-day, between-day and total precisions expressed as R.S.D., were lower than 8% at all tested quality control levels including the upper and lower limit of quantification. The limit of detection was 0.257 ng/mL for artemisinin and the calibration range was 1.03-762 ng/mL using 50 microL plasma. The method was free from matrix effects as demonstrated both graphically and quantitatively.