Novel 3-Trifluoromethyl-1,2,4-oxadiazole Analogues of Astemizole with Multi-stage Antiplasmodium Activity and In Vivo Efficacy in a Plasmodium berghei Mouse Malaria Infection Model

Iterative medicinal chemistry optimization of an ester-containing astemizole (AST) analogue 1 with an associated metabolic instability liability led to the identification of a highly potent 3-trifluoromethyl-1,2,4-oxadiazole analogue 23 (PfNF54 IC₅₀ = 0.012 μM; PfK1 IC₅₀ = 0.040 μM) displaying high microsomal metabolic stability (HLM CL_int < 11.6 μL·min^-1·mg^-1) and > 1000-fold higher selectivity over hERG compared to AST. In addition to asexual blood stage activity, the compound also shows activity against liver and gametocyte life cycle stages and demonstrates in vivo efficacy in Plasmodium berghei-infected mice at 4 × 50 mg·kg^-1 oral dose. Preliminary interrogation of the mode of action using live-cell microscopy and cellular heme speciation revealed that 23 could be affecting multiple processes in the parasitic digestive vacuole, with the possibility of a novel target at play in the organelles associated with it.

Determining diagnostic radiographer staffing requirements: A workload-based approach

INTRODUCTION

The topic of healthcare human resource planning for diagnostic radiographers has received limited research attention to date. This research is concerned with developing a framework that can be used to determine diagnostic radiographer staffing requirements at a unit- or department level (i.e. at the micro-level).

METHODS

An inductive approach is applied to formulate requirement specifications that inform the development of the framework. A number of verification and validation activities are performed, including theoretical verification and a case study application.

RESULTS

The diagnostic radiographer staffing framework consists of seven steps that comprise a workload-based approach to determining the number of full time equivalent diagnostic radiographers that are required for each modality, or group of modalities. Both clinical and non-clinical activities are considered, and guidance is provided on calculating staffing requirements to cover leave allowances. A number of potential approaches to determining activity times are also discussed.

CONCLUSION

The framework represents a holistic approach to determining the required number of diagnostic radiographers at a practice-level, that is designed to remain relevant as technological advances are made in the field of diagnostic radiography.

IMPLICATIONS FOR PRACTICE

By providing a practical guideline, with accompanying examples, the framework is expected to hold value for individuals involved in the management of diagnostic radiography practices. The framework proposes an approach to a topic that affects every radiography practice in operation yet has received limited attention in literature to date.

Oral soft-tissue manifestations as presenting symptom/sign of HIV infection

This prospective study reports oral manifestations noted in 17 patients as the first indications of HIV infection, and serves to remind health workers of the need to examine the oral soft tissues thoroughly. This study also demonstrated that other HIV-associated oral lesions are often seen in addition to the presenting symptom or sign, which was highly variable and not lesion-specific. Appropriate management of the patient after recognition of the significance of these signpost oral lesions could affect quality of life, influence the course of the disease and reduce the risk of transmission. Dentists need to be alert to and knowledgeable about these lesions which will become more prevalent as the numbers of HIV-positive persons increase in South Africa.

Intergroup comparisons of oral lesions in HIV-positive South Africans

OBJECTIVE

To determine whether there are any differences in the oral manifestations of sub-groups of persons with HIV. These data could provide information for planning of oral health promotion and prevention programmes.

DESIGN

A comparative inter-group cross-sectional investigation of the oral manifestations of HIV. Ethnic, gender and sexual orientation differences were taken into consideration.

SETTING

Three large general hospitals that offer comprehensive medical investigations and care to persons with HIV.

SUBJECTS AND METHODS

A total of 485 HIV-positive adults participated. Clinical examination and, where necessary, swabs or smears of lesions for microbiology, biopsies for histology.

MAIN OUTCOME MEASURES

Presence of lesions, associated signs, incidence and type of micro-organisms.

RESULTS

A total of 485 HIV-positive persons were examined over a period of 3 years consisting of 225 Blacks, 191 Coloureds (persons of 'mixed' descent) and 69 Whites. Data were analysed using, where relevant, the chi 2 test or Fisher's exact test. Heterosexual males revealed a higher prevalence of all oral lesions combined when compared with heterosexual females. A similar finding was evident when HIV-associated periodontal diseases was compared in these two groups. Homosexual males had a higher prevalence of candidal infections than heterosexual males. Coloured heterosexuals had a higher prevalence of oral lesions combined than black heterosexuals. All these results showed statistical significance.

CONCLUSIONS

The study tends to show that different patterns of prevalence emerge when inter-group comparisons are made of oral soft tissue diseases evident in HIV-infected South Africans.