Mechanisms of systemic resistance to pathogen infection in plants and their potential application in forestry

BACKGROUND

The complex systemic responses of tree species to fight pathogen infection necessitate attention due to the potential for yield protection in forestry.

RESULTS

In this paper, both the localized and systemic responses of model plants, such as Arabidopsis and tobacco, are reviewed. These responses were compared to information available that investigates similar responses in woody plant species and their key differences were highlighted. In addition, tree-specific responses that have been documented were summarised, with the critical responses still relying on certain systemic acquired resistance pathways. Importantly, coniferous species have been shown to utilise phenolic compounds in their immune responses. Here we also highlight the lack of focus on systemic induced susceptibility in trees, which can be important to forest health.

CONCLUSIONS

This review highlights the possible mechanisms of systemic response to infection in woody plant species, their potential applications, and where research may be best focused in future.

Population-level impact of beliefs and attitudes on vaccine decision-making in South Africa: results from the COVID-19 Vaccine Survey (2021/2022)

OBJECTIVES

In addition to being home to more than seven million HIV-infected individuals, South Africa also has a high burden of COVID-19 and related comorbidities worldwide. We aimed to identify the most influential "beliefs" and "attitudes" on vaccine decision-making behavior.

STUDY DESIGN

This study used panel data from cross-sectional surveys.

METHODS

We used the data from Black South Africans who participated in the "COVID-19 Vaccine Surveys" (November 2021 and February/March 2022) in South Africa. Besides standard risk factor analysis, such as multivariable logistic regression models, we also used the modified version of population attributable risk percent and estimated the population-level impacts of beliefs and attitudes on vaccine decision-making behavior using the methodology in multifactorial setting.

RESULTS

A total of 1399 people (57% men and 43% women) who participated in both surveys were analyzed. Of these, 336 (24%) reported being vaccinated in survey 2. Overall low perceived risk, concerns around efficacy, and safety were identified as the most influential factors and associated with 52%-72% (<40 years) and 34%-55% (40+ years) of the unvaccinated individuals.

CONCLUSION

Our findings highlighted the most influential beliefs and attitudes on vaccine decision-making and their population-level impacts, which are likely to have significant public health implications exclusively for this population.

Artificial intelligence in healthcare: Proposals for policy development in South Africa

Despite the tremendous promise offered by artificial intelligence (AI) for healthcare in South Africa, existing policy frameworks are inadequate for encouraging innovation in this field. Practical, concrete and solution-driven policy recommendations are needed to encourage the creation and use of AI systems. This article considers five distinct problematic issues which call for policy development: (i) outdated legislation; (ii) data and algorithmic bias; (iii) the impact on the healthcare workforce; (iv) the imposition of liability dilemma; and (v) a lack of innovation and development of AI systems for healthcare in South Africa. The adoption of a national policy framework that addresses these issues directly is imperative to ensure the uptake of AI development and deployment for healthcare in a safe, responsible and regulated manner.

Advocating for Front-line Health Advocates- A Scoping Review of Health Advocacy Pedagogy

Background

Health advocacy (HA) is a core competency of transformed, socially- and contextually-responsive, 21st century medical graduates though remains challenging for medical educators, including in South Africa. The optimal delivery of HA education has been vulnerable to vague definitions, lacking distinct or measurable dimensions, varied judgement, and poor prioritization in curricula which balance competing interests. We aimed to clarify HA definitions and explore current practices of HA pedagogy.

Methods

A step wise, scoping review approach was adopted, for evidence on HA and HA pedagogy. This included electronic database searches of published literature, and internet searches for non-journal publications, from 2000 to 2020 and limited to reports published in English. Websites of relevant regulatory bodies and professional organizations were also explored. Inductive thematic analysis was used to analyze the data.

Results

Sixty-four total articles and documents were included. Majority emerged from North America, the field of health education, and medical disciplines of family medicine, internal medicine, and pediatrics. HA compels graduates to be change agents and activists, at both the individual and community levels, and to promote equitable access to quality healthcare. It is increasingly associated with social accountability, consideration of the social determinants of health, and progression from advocating with, rather than for, individuals and populations. Various curricular approaches were evident, including didactic and experiential learning, and longitudinal and integrated designs.

Conclusions

Although HA is a core competency for medical graduates in South Africa, there is little evidence related to HA pedagogy in the country and the African continent. Despite distinct variability in current instructional approaches, there is potential for consolidation, contextual relevance, enhanced HA pedagogy, and improved HA competencies.

Key messages

HA is a core medical graduates’ competency but HA education is often sub-optimally engaged with and delivered. Enhanced, contextually relevant HA pedagogy could empower medical graduates to be better health advocates and more confident change agents for patients and communities they serve.

Philtrum reconstruction in unilateral cleft lip repair

The philtrum is an important aesthetic structure in the midface. A number of philtrum reconstruction techniques have been advocated for secondary cleft lip revision procedures. Conventional surgical management involves end-to-end orbicularis oris muscle approximation during primary cleft lip repair, often resulting in a flat lip appearance that requires secondary revision surgery at a later stage. A novel modification of the approximation of the orbicularis oris muscle is described that may be implemented with any cleft lip technique in order to create an accentuated philtrum column for a natural looking philtrum. The muscle roll technique results in eversion of the orbicularis oris muscle, successfully recapturing the philtrum column topography. This is achieved by utilizing two inverted horizontal sutures, with an additional philtrum takedown suture placed in the region of the dimple to accentuate the philtrum anatomy and three-dimensional profile. This novel technique in unilateral cleft lip repair addresses philtrum architecture during primary surgery, which may reduce the requirement for secondary surgical intervention. Its application may be particularly suitable in outreach programmes where postoperative follow-up may be compromised.

The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

BACKGROUND

The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications.

METHODS

ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery.

RESULTS

The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784.

CONCLUSIONS

This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance.

CLINICAL TRIAL REGISTRATION

NCT03044899.

Evaluation of locally manufactured patient-specific custom made implants for cranial defects using a silicone mould

BACKGROUND

Cranial vault defects can pose a significant problem for neurosurgeons where autologous bone is no longer available for cranioplasty. Numerous materials exist to create implants which include polymethyl methacrylate (PMMA) and titanium. A technique using 3-dimensional CT scan reconstruction of a cranial defect and creating a silicon mould which can be autoclaved in theatre to create a PMMA implant was developed.

OBJECTIVE

The aim of this study is to evaluate the efficacy, cosmetic result, safety and cost-effectiveness of this procedure and compare this to existing techniques.

METHOD

An ambispective study was performed in patients requiring cranioplasty with a custom made implant. Patients were assessed for risk factors and cosmetic outcome, surgical technique was described and complications and cost compared to existing literature between 2010 and 2016.

RESULTS

Thirty retrospective and 30 consecutive prospective patients were recruited into the study. Overall sepsis rate was 8.3%. All septic cases had superficial sepsis of which 2 grafts were removed due to cerebrospinal fluid leakage resulting in wound breakdown. A 100% accurate implant to defect ratio was achieved leading to a high satisfaction rate. Average cost was 5 times cheaper than the closest market related product.

CONCLUSION

Patient specific moulds using PMMA to create custom implants are safe, have excellent cosmetic results and are a very cost-effective option to manage cranial defects. Accurate planning strategies for large craniotomies, where bone will potentially be discarded, add to surgical effectiveness and cost-saving to the patient.

Tympanoplasty surgery: a retrospective audit of surgical outcomes at a regional hospital

BACKGROUND

Chronic Suppurative Otitis Media (CSOM) is a common condition in our setting, resulting in tympanoplasty surgery being one of the common surgical procedures performed. Little is published regarding outcomes of tympanoplasty surgery in patients living with Human Immunodeficiency Virus (HIV), which has a high prevalence in South Africa.

METHODS

A retrospective review of all tympanoplasty surgeries performed at our institute. Outcomes of surgery according to patient demographics, documented HIV status, seniority of surgeon, type and techniques of graft placement and hearing outcomes were reviewed.

RESULTS

Successful closure of perforations was 84.4%. Closure rates in the 10 patients known to be HIV positive were 100%. The number of patients meeting the criteria for The Belfast Rule of Thumb (BROT) increased from 26.3% (n = 20) preoperatively to 68.4% (n = 52) postoperatively.

CONCLUSION

The results are comparable to both the results obtained at a tertiary hospital and those published internationally. Successful outcomes are obtainable in patients infected with HIV; however, as to the optimal timing of this surgery, this would require further investigation.

Fluoride content of toothpastes available in South Africa

A high dental caries burden coupled with a lack of water or salt fluoridation make it imperative that toothpastes available to the South African consumer demonstrate adequate potential for caries control and contain between 1000ppm and 1500ppm total fluoride (TF), with at least 1000ppm F in free available/soluble form.

METHODS

The objective was to determine TF, total soluble fluoride (TSF) and insoluble fluoride (IF) concentrations in 22 fluoride toothpastes commercially available in South Africa. Samples were purchased from a major pharmaceutical and food retailer located in the two metropolitan areas in South Africa. TF and TSF concentrations were determined potentiometrically, in quadruplicate, following acid hydrolysis of the samples using a calibrated Combination Fluoride Ion Selective Electrode. IF was calculated by subtracting TSF from TF.

RESULTS

Although TF content was found to be statistically significantly lower than manufacturer declaration (3.2x10-⁷; p≤0.05), 77.3% of the samples still contained adequate free, available/soluble F levels. Relative mean TSF content for toothpastes formulated with a calcium-based abrasive was 85% (sd ±14.5; n=6) as opposed to 98.6% (sd ±2.6; n=16) for those containing silica.

CONCLUSIONS

The total fluoride concentration of all the toothpastes was lower than that declared by the manufacturers, with one in four having TSF concentrations of less than 1000ppm F. The relative TSF concentrations for the calcium-containing toothpastes were lower than for the silica-based products, reducing their preventive and protective potential. The results call for strengthened regulation and quality control of fluoride toothpastes in South Africa, as well as international efforts to improve related norms.

Release of syngnathia by anticlockwise rotation and mandibular advancement using bilateral alloplastic temporomandibular joint prostheses: a new approach

We describe a new approach to the planning of treatment and subsequent operation on a patient with syngnathia and severe mandibular retrognathism. To facilitate a large mandibular advancement we applied alloplastic temporomandibular joint (TMJ) prostheses to the coronoid processes after anticlockwise rotation of the mandible. To the best of our knowledge this is the first documented case of its kind.

Strategies for Oral Health Research in Africa and the Middle Eastern Region

The highest burden of diseases worldwide is in low- and middle-income countries, but due to lack of capacity and inadequate infrastructure, research output from these countries is unable to address existing and emerging challenges in health care. Oral health research has particularly been hampered by low prioritization, resulting in insufficient development of this sector. There is an urgent need for research correlating oral health to upstream social and environmental determinants and promoting the common risk factor approach for prevention of noncommunicable diseases. Population-wide preventive measures for oral health care are more effective than purely curative approaches, especially for vulnerable groups who have limited access to information and appropriate health care. This article identifies priorities and proposes strategies for researchers, stakeholders, and policy makers for the initiation and sustenance of appropriate oral health care research. The proposed interventions are intended to promote collaboration, capacity building, and health advocacy. Local ownership in multinational research projects in low- and middle-income countries, complemented by skills transfer from high-income countries, is encouraged to ensure that regional health needs are addressed. Emphasis is placed on a shift toward translational research that has a direct impact on oral health care systems.

Oral health effects, brushing habits and management of methamphetamine users for the general dental practitioner

BACKGROUND

Methamphetamine is a synthetic drug commonly abused in South Africa and is highly addictive. Users have a higher prevalence of dental caries compared to non-users and the classical caries pattern found in methamphetamine users is termed 'meth mouth'. The increased consumption of soft drinks and the absence of saliva are the main risk factors for 'meth mouth'.

AIM

To determine the oral health status of individuals using methamphetamine.

METHOD

A cross-sectional study was conducted on a convenience sample of 308 self-reported methamphetamine users at 22 specialised substance addiction treatment centres in the Western Cape, South Africa.

RESULTS

There was a significant difference in tooth brushing frequency when using methamphetamine (p = 0.0000022; χ(2) = 23.84; OR = 3.25). The mean decayed, missing and filled teeth score was ten and there was an association between the mean number of decayed teeth and the duration of drug addiction (p = 0.0071; χ(2) = 12.07). Users who were using methamphetamine for less than four years had fewer missing teeth compared to those who were using methamphetamine for more than four years.

CONCLUSIONS

When methamphetamine abuse is detected, the dentist can play a key role in early management of drug addiction by referring the patient to specialised substance addiction treatment centres. In addition, by restoring the dental appearance, users may regain their self-esteem and improve their oral health quality of life.

(A1) Identification of Oral Health Care Needs in Children and Adults, Management of Oral Diseases

The workshop considered five questions reviewing the identification of international oral health care needs of children and adults, and the management of oral diseases in resource-poor countries: (1) What is the role of the dental profession in the management of the HIV-infected individual? (2) Identifying health care needs-What are the epidemiology and disparities of HIV-associated oral lesions in children from different continents? (3) How effective is HIV treatment in controlling oral diseases? (4) Could we develop basic inexpensive oral and dental care protocols for economically deprived HIV-infected patients? and (5) What is the best method of arranging resources to meet the oral health care needs of people with HIV disease? The consensus of the workshop participants was that there is a need to re-target research efforts to non-established market economy countries and prioritize research in these regions to children with HIV disease. It will be important to assess commonalities and variations in oral health needs across geographical and cultural boundaries, and research efforts should be centralized in resource-poor countries to support multi-center longitudinal standardized studies. It is essential that oral health research be integrated into other health care research programs, to make these research priorities and public health initiatives feasible.

Perforated appendicitis presenting as a thigh abscess: a lethal combination

Typical cases of acute appendicitis have excellent treatment outcomes, if managed appropriately.1 We discuss an unusual case of perforated retrocaecal appendicitis that presented as a right thigh abscess without prominent abdominal symptoms, which highlights the lethal nature of advanced appendicitis even when appropriate surgical therapy is instituted.

Intestinal volvulus after conservative management of incidental midgut malrotation discovered at laparoscopic appendectomy in a teenager

Midgut malrotation (MMR) is the abnormal rotation of the foetal midgut around the axis of the superior mesenteric artery which in symptomatic neonates requires a Ladd's procedure. We present a rare case of midgut volvulus occurring in a teenager 3 days after observational management of incidentally discovered MMR during laparoscopic appendectomy. A Ladd's procedure was performed and the patient is well at one-year follow up. We suggest prophylactic Ladd's procedure remains the treatment of choice for MMR even when discovered incidentally.

Ritual tooth modification among the Baka pygmies in Cameroon

INTRODUCTION

Ritual tooth mutilation is a relatively understudied human body mutilatory practices. The purpose of the study was to examine the effects of ritual tooth modification, teeth cleaning measures and herbal medications for their oral health problems among the Baka pygmies in Cameroon.

MATERIALS AND METHODS

This cross-sectional study was conducted between January and March, 2012 using semi-structured questionnaire as the tool of data collection. Intra-oral examinations were carried out to determine the dental hard tissue loss using Smith and Knight Tooth Wear Index (TWI).

RESULTS

Fifty-six pygmies with ritual tooth modification made of 34 males (60.7%) and 22 females (39.3%) with a mean age of 31 years were interviewed and had oral health examination. The reported age at which the tooth modification was done was between 10 and 15 years with mean age as 12 ± 1.66 years. More than half (58.9%) of the participants reported the tooth filing as painful and nearly two-thirds (64.3%) of the participants reported having persistent pain afterwards. The upper right central and lateral incisors were the most commonly modified teeth. A total of 42.9%, 12.5% and 7.1% of the participants had Smith and Knight TWI scores of 2, 3 and 4 respectively. All the participants reported cleaning their teeth at least once-daily with about two-thirds (66.1%) of them doing so with chewing stick. The majority (67.9%) of the participants reported cleaning their teeth for cosmetic reasons [to remove dirt' (60.7%) and 'to remove stains' (7.1%)]. The oral health problems among the participants in form of tooth sensitivity, toothache and dental abscess were treated with plant-based traditional medicines from Irvingia gabonensis, Ricinodendron heudoletti, Pterocarpus soyauxii, Alchornea cordifolia and Piptadeniastrum africanum.

CONCLUSION

Ritual tooth modification is a painful mutilatory practice which is culturally significant for the Baka pygmies without health benefit. There is need for intervention to stop this harmful traditional practices among the pygmies. Further studies is recommended to elucidate the medicinal and pharmaceutical benefits of plants used for tooth sensitivity and other oral health problems by the pygmies.

Oblique lip-alveolar banding in patients with cleft lip and palate

We report an oblique lip-alveolar band, a rare banding of soft tissue that involves the lip and alveolus, which we have found in five patients with cleft lip and palate (0.2%), compared with an incidence of the Simonartz lip-lip band of 5.7%). To our knowledge this has not been reported previously. In two patients the bands affected the cleft lip and alveolus bilaterally, with or without the palatal cleft, and in three the bands were unilateral cleft lip and alveolus with or without the palatal cleft.

Knowledge, attitudes and practices of oral health care workers in Lesotho regarding the management of patients with oral manifestations of HIV/AIDS

Lesotho has the third highest prevalence of HIV in the world with an estimated 23% of the adult population infected. At least 70% of people living with HIV/AIDS (PLWHA) have presented with oral manifestation of HIV as the first sign of the disease. Oral health workers regularly encounter patients presenting with oral lesions associated with HIV disease and therefore need to have adequate knowledge of these conditions for diagnosis and management. The aim of the present study was to determine the knowledge, attitudes and practices of oral health care workers (OHCW) of Lesotho regarding the management of oral manifestations of HIV/AIDS. A descriptive cross-sectional survey was conducted on all 46 OHCW in 26 public and private care facilities in all ten districts of Lesotho. A self-administered questionnaire was used to gather information. The response rate was 100%. Nearly all (94.7%) agreed that oral lesions are common in people living with HIV and/or AIDS. The majority (91.3%) named oral candidiasis (OC) as the most common lesion found in PLWHA while Kaposi's Sarcoma (KS) (34.7%) and Oral Hairy Leukoplakia (OHL) (32.6%) were mentioned as the least common oral lesions of HIV. Most correctly identified the images of oral candidiasis (97.8%), angular cheilitis (86.9%) and herpes zoster (80.4%). Only 16.7% felt they had comprehensive knowledge of oral HIV lesions, although 84.8% reported having previously received training. Almost three quarters (71%) reported that there was no need to treat HIV positive patients differently from HIV negative patients. OHCW in Lesotho demonstrated high confidence levels in their competence in managing dental patients with oral lesions associated with HIV, however, they lacked an in-depth knowledge in this regard. Amongst this group there is a need for comprehensive training with regards to diagnosis and management of oral lesions of HIV including the training of other cadres of health care workers together with nurses and community health workers.

B1 but not B2 bradykinin receptor agonists promote DU145 prostate cancer cell proliferation and migration

BACKGROUND

The kallikrein-kinin system (KKS) is an endogenous pathway involved in angiogenesis and tumourigenesis, both vital for cancer growth and progression.

OBJECTIVES

To investigate the effect of two bradykinin receptor (B1R and B2R) agonists on growth and motility of prostate tumour (DU145) and micro-vascular endothelial cells (dMVECs).

METHODS

Increasing concentrations of selective B1R and B2R agonists were added to cultured cells. Cell proliferation and migration were assessed using the 3-[4,5 dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) and modified Boyden Chamber assays, respectively. Where significant stimulation was found, the influence of an antagonist was also investigated.

RESULTS

Neither growth nor motility of endothelial cells was affected by either agonist. In DU145 cells, while the B2R agonist was without any significant effect, the B1R agonist stimulated proliferation and migration at concentrations of 10nM and 50nM respectively. Further, this effect was abrogated when cells were pre-incubated with a B1R antagonist.

CONCLUSIONS

Unlike the physiologically-active B2R, the pathologically-inducible B1R may be implicated in prostate tumourigenic events. The involvement of the KKS in malignant prostate pathology supports on-going exploration of bradykinin receptor antagonists as target candidates in the development of alternate approaches to cancer therapy.

Minors' request for confidentiality

Dentists must be cognisant of what the law requires and how they are expected to respond. When the law does not address an issue, the dentist would need to weigh the circumstances and consequences and do what he/she thinks is ethically appropriate and acceptable. The need to maintain confidentiality of any information given to us in our professional capacity is paramount. Patient autonomy and their absolute right to confidentiality must be ensured in almost all but the most exceptional circumstances. Patients have the ethical and legal right to expect a health professional to keep confidential the information provided during the course of their care. Disclosure of patient information is only permitted with the patient's consent or if there is an overwhelming public interest in disclosure as prescribed by the law.

Impact of socio-economic factors on quality of life in patients on continuous ambulatory peritoneal dialysis in an African setting

BACKGROUND

Quality of life (QOL) is an important outcome following the treatment of disease. It is influenced by physical, psychological, social and economic factors. We proposed to determine the effect of some socioeconomic factors on QOL of patients on CAPD.

STUDY DESIGN

A cross sectional study in which all patients on CAPD attending three clinics attached to the University of the Witwatersrand, Johannesburg were recruited excluding those with intercurrent illness. The WHO quality of life instrument, WHOQOL-Bref, was used to measure QOL. The patients were grouped according to marital status, highest level of education attained, income, employment, and QOL domain scores were compared using ANOVA and Student t test.

RESULTS

A total of 140 patients comprising 80 males and 40 females were assessed. The mean age of patients was 41.9 ± 11.5 years, 95%of patients were black, 44.3% married, 69.3% had secondary education, 22% were employed and 51.4% had a monthly income of less than five thousand Rand (500 US dollars). Single patients scored better in the social relationships domain compared to separated patients (p=0.02, CI: 5.6-32.9). The group with secondary education scored low in the psychological domain compared with those with primary education (p=0.02, CI: 1.35-15.8) and those with tertiary education (p=0.02, CI: 1.72-18.07).The highest income group had best scores in all domains except the physical domain. Those in employment had better scores in the physical domain (p=0.04, CI: 0.356-12.549).

CONCLUSION

Income had the most impact on QOL in study participants.

Lower frequency of NPM1 and FLT3-ITD mutations in a South African adult de novo AML cohort

INTRODUCTION

Acute myeloid leukemia (AML) is a heterogeneous clonal disorder of hemopoietic progenitor cells diagnosed in individuals of any age, but with a median age of 67 years at presentation in adults. Assessment of the mutation status of nucleophosmin protein-1 (NPM1) and FMS-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) is essential for the prognosis, and treatment of AML.

METHODS

A total of 160 de novo AML cases, both cytogenetically normal and abnormal, were analyzed for the presence of NPM1 and FLT3-ITD mutations, and the results assessed in conjunction with epidemiological, clinical, and laboratory findings.

RESULTS

Nucleophosmin protein-1 mutations were found in 7.5%, while FLT3-ITD was present in 12% of these cases. Both of these were lower than expected. The median age at diagnosis of AML was 41 years, and for the FLT3-ITD only cases, median age was 33 years; these ages were younger than expected.

CONCLUSION

The lower reported frequencies and younger median age at diagnosis of AML and these specific mutations may be contributed to by a number of factors including effects of race on age of presentation, inclusion of patients diagnosed with de novo AML only, and a generally younger median age of the South African population.