A teaching model for biomedical imaging informatics.

INTRODUCTION: Radiology played a leading role in the transformation of medicine to a digital environment. To ensure the smooth operation and managing workflow in a digital imaging environment, dedicated, well-trained individuals are needed. The objective of this study was to develop a teaching and learning model for imaging informatics. METHODS: Quantitative and qualitative data were collected through a literature review and three structured questionnaires. Results from literature and questionnaires informed the Delphi statements. Three Delphi rounds with medical informatics and higher education experts were completed - all data contributed to developing the teaching and learning model. RESULTS: Literature provided the frame of reference related to regulation and inclusions in the model. Six summated imaging informatics themes with categories that included topics, teaching, learning and assessment as well as project management, and clinical engineering were included in the first Delphi questionnaire. The three-round Delphi resulted in consensus achieved for 142 of the 184 statements and the stability of 37 statements. The model created aligns with the context, goals, content, learning experiences and assessment that lead to holistic student development. CONCLUSION: Feedback from a variety of sources assisted the development of the teaching model for image informatics. The model can be regarded as having a broad scope but also depth since expert refinement strengthened the final inclusions. The flexible, holistic nature of this model addresses not only the educational impediments associated with curriculum development but additionally catalyses a pragmatic approach to implementation and operationalisation thereof. IMPLICATIONS FOR PRACTICE: The developed teaching and learning model could serve to improve the training of radiographers and IT specialists to become certified imaging informatics professionals. This model may be incorporated to assist the integration of all systems - to improve quality and service.

MinION 16S datasets of a commercially available microbial community enables the evaluation of DNA extractions and data analyses.

New advances in sequencing technology and bioinformatics analysis tools have significantly supported the culture-independent analysis of complex microbial communities associated with environmental, plant, animal and human samples. However, previous work has shown that DNA extraction can have a major influence in the community profile. As such there is a constant need for new methods to efficiently and rapidly prepare and analyze DNA for microbiome research, especially in the case new and emerging technology like the Oxford Nanopore Technologies (ONT) MinION. A commercial standard was used, in triplicate, to evaluate three DNA extraction protocols, including two commercially available and one "in-house" DNA extraction method. All DNA extractions were done as per manufacturer's instructions and prepared with the same commercial ONT 16S sample preparation kit, prior to being analysed using MinION sequencing. Eight MinION 16S datasets of this microbial reference community were obtained. Reads were initially base called and demultiplexed using ONT's Guppy™ sequencing software (version 3.2.4), filtered using NanoFilt and then classified using Usearch. A set of R scripts are presented to process sintax files generated from Usearch and produce an OTU table that can be used for further analyses. All datasets were deposited into the SRA (NCBI) database. These datasets will allow future extraction kit comparisons using MinION sequencing since a standardize laboratory process using commercially available components, such as the MinION 16S sample preparation kit, microbial reference community and extraction kits, were used. The current ONT 16S workflow making use of the Epi2me agent only provides QC metrics and the ID's of the main genera identified and does not provide any tools currently for further downstream community comparison. The analyses scripts provided in the supplementary material will thus further enable the testing of new datasets against these reference sets and provide users the ability to compare their workflows with ours, thus standardizing comparisons and workflows.

Feedback during summative clinical assessments: Experiences of diagnostic radiography students at a higher education institution in South Africa.

INTRODUCTION: Summative clinical assessments and feedback, conducted at clinical training sites, are vital for successfully preparing undergraduate diagnostic radiography students to become competent, skilled diagnostic radiographers. However, providing appropriate feedback in a clinical context is a complex matter, as studies show that students often feel intimidated by feedback and may only accept feedback selectively, so as to pass their assessment or course. This article reports on the experiences of radiography students regarding summative clinical assessment feedback. METHODS: A qualitative, exploratory, descriptive, and contextual research design was used. Data were gathered from radiography students at one higher education institution in South Africa who were registered in year three and year four of a four-year professional Diagnostic Radiography degree. Five semi-structured focus group interviews were conducted, with 26 participants in total. Focus group interviews were audio recorded, transcribed verbatim and coded using Tesch's data analysis method. RESULTS: Two principle themes emerged from the data analysis. Theme 1 unpacked whether radiography students viewed the assessor as an ally or foe. It was found that various assessor-related characteristics influenced radiography students receptivity towards feedback and this was related to how they viewed the assessor. Theme 2 concerned the radiography students' perceptions of the key elements influencing the nature of a feedback process. These elements were influenced primarily by the assessor, but the attitudes of radiography students towards the feedback process were also important. CONCLUSION: Radiography students reported various positive experiences regarding assessor feedback during the summative clinical assessments. However, they were also dissatisfied with numerous aspects of how the assessors provided feedback often viewing the assessor as one who is a foe or who is opposed to their success. Subsequently the negative aspects of the feedback process hampered the learning experience of the participants. IMPLICATIONS FOR PRACTICE: Awareness and the development of feedback skills for assessors and radiography students would be beneficial to the learning process. Radiography students, the radiography profession and ultimately the patients would benefit from the effects of effective feedback.

Radiographers' experiences of the management of quality assurance programmes in public hospitals, South Africa.

INTRODUCTION: In radiology departments, quality assurance (QA) is central to the production of good quality images. Radiographers who manage QA programmes are often faced with challenges that hinder the execution of the required quality control (QC) tests. The objective of this research study was to explore and describe the experiences of diagnostic radiographers and radiography managers who are responsible for the management of QA programmes in digital diagnostic imaging departments (DDIDs) in public hospitals of a large metropolitan area. This study was conducted in a South African (RSA) context. METHODS: A qualitative, explorative, descriptive, and contextual research design was utilised, data were collected by means of semi-structured interviews. The target population comprised of 16 public hospital radiographers and radiography managers and data collection continued until data saturation was achieved (n = 10). RESULTS: The participants provided pragmatic information regarding their experiences of the management of QA programmes in public DDIDs from which two main themes emerged. The first indicated that management support is required to ensure the success of the QA programme. The second provided suggestions on how to optimise the QA programme. CONCLUSION: Participants articulated the importance of management guidance in QA programmes, with specific emphasis on staffing, training, time allocation and budgeting. Difficulties in terms of equipment maintenance were linked to inadequate budgeting. Participants experienced a need for all staff to be trained and involved in the QA programme in order to reduce delay in the performance of the QC tests when the QA officer was not available.

Transitioning from analogue to digital imaging: Challenges of South African analogue-trained radiographers.

INTRODUCTION: The work of a radiographer includes using technology to produce x-ray images. The technology employed could either be analogue or digital technology. Over the last 20-25 years analogue-trained radiographers in South Africa have had to produce x-ray images using digital technology. The aim of this paper is to explore and describe the experiences of analogue-trained radiographers utilising digital imaging in projection radiography. METHODS: The study used a qualitative, exploratory, descriptive design. Purposive sampling was employed and individual, in-depth, semi-structured interviews were conducted. RESULTS: Two themes emanated from the data. The first concerned the evolution of the radiographer when faced with the advances in technology. The second addressed the role that the work environment played in the manner that the participants experienced the change. CONCLUSION: Evidence was found of radiographer indifference towards exposure selection, dose optimisation and placement of anatomical side markers in the primary beam when using digital imaging. Further evidence emerged of interprofessional and intergenerational conflict as a result of the introduction of the new technology.

Modeling nanoparticle delivery of TB drugs to granulomas.

Tuberculosis, which typically presents as a pulmonary disease, has a complex pathology. The primary site of infection, the Ghon focus, recruits immune cells and a granuloma forms. At earlier stages the granuloma is still vascularized, offering the best opportunity for drug treatment. In the more progressive state blood flow is reduced and a distinct caseous structure develops. Effective delivery of drugs to bacilli in the core of the granuloma becomes very difficult. It is perceivable that granuloma cores could create conditions where bacilli persist and develop resistance. In this study we analyze drug delivery to granulomas by means of a nanoparticle delivery system. The model consists of two parts; the overall distribution of the nanoparticles is described by a simple circulatory model and this result is used in the second part, focusing on transport in a capillary lined with macrophages. Nanoparticles enter the macrophages where they are metabolized and the drugs are released. The model reveals significant differences in drug concentrations between the plasma and macrophages. Based on the results of the model, strategies for improved drug delivery are proposed.

Skin lightening practices: an epidemiological study of South African women of African and Indian ancestries.

BACKGROUND: Cutaneous adverse sequelae of skin lightening creams present with myriad skin complications and affect dermatology practice, particularly in sub-Saharan Africa where such products are widely used, with a prevalence of 25-67%. OBJECTIVES: To examine the skin lightening practices of both African and Indian women living in South Africa. METHODS: A cross-sectional survey was undertaken in the general outpatient departments of two regional university hospitals in Durban, South Africa. All consenting African and Indian women aged 18-70 years were recruited and asked to complete a questionnaire. RESULTS: Six hundred women completed the questionnaire, of whom 32·7% reported using skin lightening products. The main reasons cited were treatment of skin problems (66·7%) and skin lightening (33·3%). Products were purchased from a variety of sources. Twenty-five percent reported using sunscreen. CONCLUSIONS: The use of skin lightening cosmetics is common among darkly pigmented South African women, including those of both African and Indian ancestries. Despite more than 20 years of governmental regulations aimed at prohibiting both the sale of cosmetics containing mercury, hydroquinone and corticosteroids, and the advertising of any kind of skin lightener, they are far from having disappeared. The main motivations for using these products are the desire to treat skin disorders and to achieve a lighter skin colour. Television and magazine advertisements seem to influence women's choice of these products and, thus, would be efficient channels for raising public awareness about the dangers of using uncontrolled skin lighteners.

Improved survival in multidrug-resistant tuberculosis patients receiving integrated tuberculosis and antiretroviral treatment in the SAPiT Trial.

BACKGROUND: The therapeutic effects of antiretroviral treatment (ART) in patients with multidrug-resistant tuberculosis (MDR-TB) and human immunodeficiency virus (HIV) infection have not been established. OBJECTIVE: To assess therapeutic outcomes of integrating ART with treatment for MDR-TB. DESIGN: A subgroup of MDR-TB patients from a randomised controlled trial, the SAPiT (Starting Antiretroviral Therapy at Three Points in Tuberculosis) study, conducted in an out-patient clinic in Durban, South Africa, from 2008 to 2012. METHODS: Clinical outcomes at 18 months were compared in patients randomised to receive ART within 12 weeks of initiating standard first-line anti-tuberculosis treatment with those who commenced ART after completing anti-tuberculosis treatment. RESULTS: Mycobacterium tuberculosis drug susceptibility results were available in 489 (76%) of 642 SAPiT patients: 23 had MDR-TB, 14 in the integrated treatment arm and 9 in the sequential treatment arm. At 18 months, the mortality rate was 11.9/100 person-years (py; 95%CI 1.4-42.8) in the combined integrated treatment arm and 56.0/100 py (95%CI 18.2-130.8) in the sequential treatment arm (hazard ratio adjusted for baseline CD4 count and whether MDR-TB treatment was initiated: 0.14; 95%CI 0.02-0.94, P = 0.04). CONCLUSION: Despite the small sample size, the 86% reduction in mortality due to early initiation of ART in MDR-TB patients was statistically significant.

Key issues in the clinical development and implementation of TB vaccines in South Africa.

Significant progress has been made in advancing the development pipeline for a new and more effective TB vaccine with some candidate vaccines now in late stage clinical evaluation. However, progress has been hampered by an incomplete understanding of the components of a protective immune response and limited animal models, rendering the field unable to reliably predict vaccine efficacy earlier in preclinical development, including by evaluation in animal models, and limiting the predictive utility of comparing immunogenic effects across vaccine candidates in phase I/II studies. Consequently, new candidate vaccines have to be evaluated for efficacy in large-scale phase II/III trials using clinical endpoints. Apart from the technical challenges of characterising TB incidence in target populations at high risk of acquiring TB disease and standardising case definitions in order to improve both the sensitivity and more importantly the specificity of trial endpoints, there is an urgency in expanding and supporting the considerable trial infrastructure that will be required to evaluate and ultimately license a new TB vaccine. In the longer term, implementation strategies are dependent on what policy makers most value. Economic analyses will be essential to guide policy and implementation. This paper outlines the gaps and challenges and identifies solutions for effectively developing and efficiently introducing a new TB vaccine.

Topical and transdermal delivery of L-carnitine.

BACKGROUND: The two types of skin aging (intrinsic and extrinsic) share important molecular features, while having distinct differences on the macromolecular level: both lead to increased production of reactive oxygen species, enhanced matrix metalloproteinase expression and decreased procollagen synthesis. L-Carnitine L-tartrate has been reported to have anti-aging effects. AIM AND METHODS: The delivery as well as the transport of L-carnitine to the target sites, i.e. stratum corneum and epidermis-dermis of female abdominal skin, with and without the use of Pheroid™ as delivery system, were investigated during this study by use of Franz diffusion cells and analysed by liquid chromatography/mass spectrometry. The presence of endogenous L-carnitine in human skin was also investigated. RESULTS AND CONCLUSION: The Pheroid™ delivery system enhanced the diffusion of L-carnitine through the skin, although the phosphate buffer solution (PBS) showed a higher concentration of the active agent in the skin layers. This could be because Pheroid, being more lipophilic than PBS, improved the diffusion of L-carnitine through the skin layers, consequently leading to a lesser amount of L-carnitine delivered to the target site, i.e. the epidermis-dermis.

A case study of rabies diagnosis from formalin-fixed brain material.

Rabies is caused by several Lyssavirus species, a group of negative sense RNA viruses. Although rabies is preventable, it is often neglected particularly in developing countries in the face of many competing public and veterinary health priorities. Epidemiological information based on laboratory-based surveillance data is critical to adequately strategise control and prevention plans. In this regard the fluorescent antibody test for rabies virus antigen in brain tissues is still considered the basic requirement for laboratory confirmation of animal cases. Occasionally brain tissues from suspected rabid animals are still submitted in formalin, although this has been discouraged for a number of years. Immunohistochemical testing or a modified fluorescent antibody technique can be performed on such samples. However, this method is cumbersome and cannot distinguish between different Lyssavirus species. Owing to RNA degradation in formalin-fixed tissues, conventional RT-PCR methodologies have also been proven to be unreliable. This report is concerned with a rabies case in a domestic dog from an area in South Africa where rabies is not common. Typing of the virus involved was therefore important, but the only available sample was submitted as a formalin-fixed specimen. A real-time RT-PCR method was therefore applied and it was possible to confirm rabies and obtain phylogenetic information that indicated a close relationship between this virus and the canid rabies virus variants from another province (KwaZulu-Natal) in South Africa.

In vitro cytotoxicity of chlorhexidine gluconate, benzydamine-HCl and povidone iodine mouthrinses on human gingival fibroblasts.

Mouthrinses are frequently prescribed for the treatment of ulcerative diseases of the oral mucosa. In this study the in vitro cytotoxic effect of 0.2% chlorhexidine gluconate in water, 0.15% benzydamine-HCl in 8.5% ethanol and 1% povidone iodine in 10% ethanol were determined. Results of photographs and cell counts revealed that all the cells exposed to chlorhexidine gluconate, benzydamine-HCl and povidone iodine were immediately fixated onto the tissue culture surfaces. The three agents were then diluted in phosphate buffered saline to concentrations varying between 10% and 90% and fibroblasts were once again exposed to the dilutions of the test agents. Photographs were taken and cell concentrations in the wells were determined immediately after exposure and after 2, 4 and 24 hours. Results indicated that cells were immediately fixated by 10% chlorhexidine gluconate in water, 20% povidone iodine and 70% benzydamine-HCl. Fibroblasts survived and recovered from the exposure to 8.5% and 10% ethanol, which indicated that the fixation effect is not the result of the ethanol, but should be ascribed to the activity of the active ingredients in the mouthrinses.

A novel skin penetration enhancer: evaluation by membrane diffusion and confocal microscopy.

PURPOSE: The aim of this study was to determine the in vitro transdermal efficacy of a Meyer Zall Laboratories (MZL) oil/water emulsion in two separate preparations containing the actives, coal tar and the non-steroidal anti-inflammatory drug, diclofenac sodium. METHOD: The release rate of the two active ingredients from MZL dermatological preparations, Exorex and Athru-Derm and four comparator products was determined using an enhancer cell system, whilst specific penetration characteristics of the MZL formulation were elucidated using confocal and electron microscopy. The latter properties were explored at both the organ level, using human skin, as well as at a cellular level using a melanoma cell line. RESULTS: While the in vitro release rates for all formulations was high, coal tar and diclofenac release from Exorex and Athru-Derm respectively was, at nearly all time intervals, significantly higher than from comparator products. Microscopy revealed the presence of spherical liposomal type structures in both the MZL lotion and a comparator gel. In the MZL lotion, the majority of these structures, referred to here as emzaloid particles, were in the order of magnitude of about 50 nm to 1 microm in diameter with a small minority exceeding these dimensions. After application of Athru-Derm to human skin, intact emzaloid particles of submicron dimensions were detected in the epidermis in association with the cell membranes. The affinity of the MZL lotion for cell membranes was further demonstrated with melanoma cells; in addition, the formulation was seen to penetrate even to the nucleus of viable cells. CONCLUSION: Overall the data suggest that the oil/water base in MZL formulations is a highly efficient transdermal vehicle able to transport a wide range of indication- specific actives to their site of action.

Bacterial meningitis in children at Kalafong Hospital, 1990-1995.

OBJECTIVES: To determine the bacteriological profile, morbidity, mortality and factors which contributed to the outcome. DESIGN: Retrospective descriptive. SETTING: Kalafong Hospital, Pretoria. SUBJECTS: Children older than 1 month and younger than 13 years admitted between January 1990 and December 1995 with culture-proven bacterial meningitis. MAIN OUTCOME MEASURES: Causative bacteria, antibiotic sensitivity, age, clinical features and short-term morbidity and mortality. RESULTS: Sixty-one patients had culture-proven bacterial meningitis. In 57% Haemophilus influenzae, in 33% Streptococcus pneumoniae and in 1.6% (1 patient) Neisseria meningitidis were cultured (5 patients yielded other organisms). Some H. influenzae cultures showed resistance to cefotaxime and ampicillin and some S. pneumoniae cultures to penicillin. The mean age of all patients was 18 months. Twenty-three per cent of the patients had consulted between 1 and 5 health workers and were then self-referred. Fever, cough and vomiting were the most common complaints. On examination, fever and pneumonia were the most common findings apart from neurological system involvement. Twelve patients (20%) died and 46% were discharged with obvious neurological complications. Morbidity and mortality were the highest for S. pneumoniae meningitis. Bad prognostic features were delayed referral, S. pneumoniae meningitis, convulsions and abnormal neurological signs on admission. CONCLUSION: H. influenzae was the most common cause of childhood bacterial meningitis at Kalafong Hospital, with N. meningitidis meningitis being very rare. Morbidity and mortality were very high, compared with outcome in developed countries. Delayed referral seems to be an important factor in predicting an adverse outcome.

The possible role of sodium-potassium adenosine triphosphatase in preterm labour.

An unacceptably high incidence of preterm labour is seen in the black and coloured communities of South Africa. This hypothesis proposes that sodium-potassium adenosine triphosphatase activity plays an important role in preterm labour. The impaired activity of the sodium pump leads to increased cytosolic calcium levels, which may trigger contraction of myometrial smooth-muscle cells, resulting in preterm labour.