Immunohistochemical expression of CD56 in dog (Canis familiaris) odontogenesis

AIM : To investigate the expression of CD56 in dog odontogenesis in order to elucidate the expression found in ameloblastomas. MATERIALS AND METHODS : Immunohistochemical analysis of CD56 expression of developing dog teeth in the bud, cap and bell stages including the remnants of the dental lamina. RESULTS : Weak CD56 expression was observed in the dental epithelium during the bud stage with intense staining of certain peripheral epithelial cells. Positive staining of epithelial cells was also observed in the cap stage with intense staining of the inner enamel epithelium at this stage. During the bell stage the staining was concentrated on the cervical loop areas. The dental papilla revealed positive staining throughout the cap and bell stages while the dental follicle stained intensely positive throughout all the phases examined. The dental lamina and Serres rests also stained positive for CD56. CONCLUSIONS : The expression of CD56 in dog odontogenic tissue varies according to the stage of tooth development. There is a positive correlation between the positive staining observed in ameloblastomas and their odontogenic cells of origin.http://www.elsevier.com/locate/aob2016-10-31hb201

Oral Plasmablastic Lymphoma: A clinicopathological study of 113 cases

https://drive.google.com/file/d/12WkwlN-xh9ZhZoahJ_c-N4zwuiLBZ0x8/view?usp=sharinghttps://drive.google.com/drive/folders/1Rm_GimQtumx7roigsBwBPMnhFTTUZ-UC?usp=sharinghttps://drive.google.com/drive/folders/1TtTOHdcYPzNddB4h2MCDaXeYTkkHn_v7?usp=sharin

The prognostic signifi cance of normal technetium-99m MIBI myocardial perfusion spect imaging over a four-year follow-up period

normal Tc-99m MIBI myocardial perfusion study has previously been shown to indicate a benign prognosis. Our aim was to determine the longer term prognosis of a normal study in our patient population. Methods: A retrospective evaluation of 209 patients with a normal Tc-99m MIBI study was performed. Follow-up data was obtained in 157 patients, with complete follow-up in 121 (mean follow-up period of 56 months). In 36 patients only partial follow-up was possible (32 months follow-up). No follow-up data, except for the possible registration of deaths, could be obtained in 52. Patients were evaluated for the occurrence of primary or secondary cardiac events. Results: The study group had a moderate pre-test probability for coronary artery disease (48 + 30.7%). Two possible cardiac deaths occurred (cardiac death rate of 0.95%). No primary events occurred in the group with complete follow-up, but 6 secondary events were recorded (cardiac event rate of 4.9%). No primary or secondary events occurred in the partial follow-up group during the follow-up period. The incidence of secondary or non-fatal primary events in this group for the period after they were lost to follow-up or in the group with no follow-up could not be ascertained. There was, however, no statistically significant difference between these groups regarding age, pre-test probability and exercise parameters. Conclusion: Similar to the findings with Tl-201, our study indicates a favourable longer term prognosis after a normal Tc-99m MIBI study

Correlation between dysplasia and ploidy status in oral leukoplakia

Oral leukoplakia and other potentially malignant disorders (PMD) may progress to oral squamous cell carcinoma (OSCC). The gold standard for assessing the potential for malignant transformation remains histologic examination with the aim of grading the dysplastic changes. However, not all lesions with dysplasia will progress to OSCC. DNA ploidy has been suggested as a method to predict the clinical behaviour of PMD. This study reports on the use of high-resolution flow cytometry to determine the ploidy status of formalin-fixed, paraffin-embedded material from PMD compared to their dysplasia grade on histology. Aneuploidy was found in 13 % of mild, 31 % of moderate, and 54 % of severe dysplasia cases. This difference was statistically significant (p = 0.011). The differences in ploidy status were more significant when grouping the dysplasia into low-risk and high-risk categories (p = 0.008). These findings indicate that the ploidy status of PMD as determined by high-resolution flow cytometry may be of value in predicting biological behaviour in PMD such as leukoplakia.The National Research Foundation of South Africahttp://link.springer.com/journal/1210

Making use of an existing questionnaire to measure patient-centred attitudes in undergraduate medical students : a case study

CITATION: Archer, E., Bezuidenhout, J., Kidd, M. & Van Heerden, B.B. 2014. Making use of an existing questionnaire to measure patient-centred attitudes in undergraduate medical students: A case study. African Journal of Health Professions Education, 6(2):150-154, doi:10.7196/ajhpe.351.The original publication is available at http://www.ajhpe.org.zaBackground. Patient-centred care is widely acknowledged as important to achieve improved patient outcomes in healthcare. Therefore, it is vital that medical schools should foster this attitude in their students. Studies report that students are becoming less patient-centred in the period between entry to medical school and graduation. Objective. To determine the shift in attitude towards patient-centredness in a group of South African undergraduate medical students. Simultaneously, the reliability and validity of the Patient-Practitioner Orientation Scale (PPOS) in our context were measured. Methods. A cross-sectional survey was undertaken by asking all the medical students from year 1 to year 6 to complete the PPOS. The mean PPOS score for each cohort was calculated using SPSS for Windows. Reliability and validity testing was conducted using Cronbach’s alpha and confirmatory and exploratory factor analysis. Results. The average return rate across the 6 years of study was 81%. The results indicated low initial scores on the PPOS and a decrease in scores over the years of study, with the most dramatic drop being from year 1 to year 2. The PPOS showed poor validity and reliability in our context. Conclusion. The study appears to indicate the same decrease in patient-centredness in our students as has been shown in other studies using this tool. However, the low reliability and validity of the PPOS in our environment means that the result should be interpreted with caution. Factors such as our medical students’ not having had first-hand experience of the doctor-patient relationship and second-language issues may play a role. It is recommended that the PPOS not be used in our context without further exploration of the factors contributing to this loss of reliability and validity.http://www.ajhpe.org.za/index.php/ajhpe/article/view/351Publisher's versio

‘Going the extra mile’: Supervisors’ perspectives on what makes a ‘good’ intern

Background. Much has been published on whether newly graduated doctors are ready for practice, seeking to understand how to better prepare graduates for the workplace. Most studies focus on undergraduate education as preparation for internship by investigating knowledge and skills in relation to clinical proficiencies. The conversion from medical student to internship, however, is influenced not only by medical competencies, but also by personal characteristics and organisational skills. Most research focuses largely on the interns’ own perceptions of their preparation. Supervisors who work closely with interns could therefore present alternative perspectives.Objectives. To explore the views of medical intern supervisors on the internship training context, as well as their perspectives on attributes that would help an intern to function optimally in the public health sector in South Africa (SA). This article intends to extend our current understanding of what contributes to a successful internship by including the views of internship supervisors.Methods. Twenty-seven semi-structured interviews were held with medical intern supervisors in 7 of the 9 provinces of SA. The data were thematically analysed and reported using an existing framework, the Work Readiness Scale.Results. The intern supervisors indicated that interns were challenged by the transition from student to doctor, having to adapt to a new environment, work long hours and deal with a large workload. Clinical competencies, as well as attributes related to organisational acumen, social intelligence and personal characteristics, were identified as being important to prepare interns for the workplace. Diligence, reliability, self-discipline and a willingness to work (‘go the extra mile’) emerged as key for a ‘good’ intern. The importance of organisational skills such as triage, prioritisation and participation was foregrounded, as were social skills such as teamwork and adaptability.Conclusions. This article contributes to our understanding of what makes a successful medical internship by exploring the previously uncanvassed views of intern supervisors who are working at the coalface in the public health sector. It is envisaged that this work will stimulate debate among the medical fraternity on how best to prepare interns for the realities of the workplace. Educational institutions, health services and interns themselves need to take ownership of how to instil, develop and support these important attributes

Prevalence and correlates of atypical patterns of drug use progression: findings from the South African Stress and Health Study

Objective: Atypical sequences of drug use progression are thought to have important implications for the development of substance dependence. The extent to which this assumption holds for South African populations is unknown. This paper attempts to address this gap by examining the prevalence and correlates of atypical patterns of drug progression among South Africans. Method: Data on substance use and other mental health disorders from a nationally representative sample of 4351 South Africans were analysed. Weighted cross tabulations were used to estimate prevalence and correlates of atypical patterns of drug use progression. Results: Overall, 12.2% of the sample reported atypical patterns of drug use progression. The most common violation was the use of extra-medical drugs prior to alcohol and tobacco. Gender was significantly associated with atypical patterns of drug use with the risk pattern varying by the type of drug. None of the anxiety or mood disorders were associated with atypical patterns of use. Atypical patterns of drug use were not associated with increased risk for a lifetime substance use disorder. Conclusion: Atypical patterns of drug use initiation seem more prevalent in South Africa compared to other countries. The early use of extra-medical drugs is common, especially among young women. Drug availability and social environmental factors may influence patterns of drug use. The findings have important implications for prevention initiatives and future research.Key words: Substance use; Gateway violations; Mental disorders; South Afric

Dominant genetic aberrations and coexistent EBV infection in HIV-related oral plasmablastic lymphomas

We present common cytogenetic features in the largest cohort of plasmablastic lymphoma (PBL) of the oral cavity published to date. This cohort included 45 patients, 32 of whom had a known HIV status, of which 31 were HIV positive. Ninety eight per cent of all PBL cases were known to be EBV positive. In line with previous studies, we found that rearrangements of the MYC gene was the most common genetic abnormality seen in 60% of cases with the immunoglobulin heavy chain (IGH) locus as a partner in 51% of cases. Additional complex genetic aberrations were frequent, in particular, an increased copy number of the CCND1 gene was seen in 41% of cases with true amplification of CCND1 in 15% of cases. Aneuploidy was also observed for the BCL6 gene in 28% of cases. Interestingly, rearrangements of both IGH genes were detected in 16% of cases with t(14;18) and t(11;14) respectively involved in conjunction with a t(8;14) in two cases. These bi-allelic IGH rearrangements have not been described before in oral PBL. Our results reinforce the notion that EBV infection and MYC rearrangements are important events in the pathogenesis of oral PBL. The genetic diversity and complexity observed in these cases, underlines the importance to genetically characterise PBL patients at presentation as this may inform the choice of more effective treatment modalities.Grants from the South African Dental Association, National Research Foundation and National Health Laboratory Services Research Trust, South Africa.http://www.elsevier.com/locate/oraloncolog

The good, the bad and the ugly: pandemic priority decisions and triage.

In this analysis we discuss the change in criteria for triage of patients during three different phases of a pandemic like COVID-19, seen from the critical care point of view. Availability of critical care beds has become a hot topic, and in many countries, we have seen a huge increase in the provision of temporary intensive care bed capacity. However, there is a limit where the hospitals may run out of resources to provide critical care, which is heavily dependent on trained staff, just-in-time supply chains for clinical consumables and drugs and advanced equipment. In the first (good) phase, we can still do clinical prioritisation and decision-making as usual, based on the need for intensive care and prognostication: what are the odds for a good result with regard to survival and quality of life. In the next (bad phase), the resources are mostly available, but the system is stressed by many patients arriving over a short time period and auxiliary beds in different places in the hospital being used. We may have to abandon admittance of patients with doubtful prognosis. In the last (ugly) phase, usual medical triage and priority setting may not be sufficient to decrease inflow and there may not be enough intensive care unit beds available. In this phase different criteria must be applied using a utilitarian approach for triage. We argue that this is an important transition where society, and not physicians, must provide guidance to support triage that is no longer based on medical priorities alone

Evaluation of tuberculosis diagnostic test accuracy using Bayesian latent class analysis in the presence of conditional dependence between the diagnostic tests used in a community-based tuberculosis screening study

Diagnostic accuracy studies in pulmonary tuberculosis (PTB) are complicated by the lack of a perfect reference standard. This limitation can be handled using latent class analysis (LCA), assuming independence between diagnostic test results conditional on the true unobserved PTB status. Test results could remain dependent, however, e.g. with diagnostic tests based on a similar biological basis. If ignored, this gives misleading inferences. Our secondary analysis of data collected during the first year (May 2018 -May 2019) of a community-based multi-morbidity screening program conducted in the rural uMkhanyakude district of KwaZulu Natal, South Africa, used Bayesian LCA. Residents of the catchment area, aged >/=15 years and eligible for microbiological testing, were analyzed. Probit regression methods for dependent binary data sequentially regressed each binary test outcome on other observed test results, measured covariates and the true unobserved PTB status. Unknown model parameters were assigned Gaussian priors to evaluate overall PTB prevalence and diagnostic accuracy of 6 tests used to screen for PTB: any TB symptom, radiologist conclusion, Computer Aided Detection for TB version 5 (CAD4TBv5>/=53), CAD4TBv6>/=53, Xpert Ultra (excluding trace) and culture. Before the application of our proposed model, we evaluated its performance using a previously published childhood pulmonary TB (CPTB) dataset. Standard LCA assuming conditional independence yielded an unrealistic prevalence estimate of 18.6% which was not resolved by accounting for conditional dependence among the true PTB cases only. Allowing, also, for conditional dependence among the true non-PTB cases produced a 1.1% plausible prevalence. After incorporating age, sex, and HIV status in the analysis, we obtained 0.9% (95% CrI: 0.6, 1.3) overall prevalence. Males had higher PTB prevalence compared to females (1.2% vs. 0.8%). Similarly, HIV+ had a higher PTB prevalence compared to HIV- (1.3% vs. 0.8%). The overall sensitivity for Xpert Ultra (excluding trace) and culture were 62.2% (95% CrI: 48.7, 74.4) and 75.9% (95% CrI: 61.9, 89.2), respectively. Any chest X-ray abnormality, CAD4TBv5>/=53 and CAD4TBv6>/=53 had similar overall sensitivity. Up to 73.3% (95% CrI: 61.4, 83.4) of all true PTB cases did not report TB symptoms. Our flexible modelling approach yields plausible, easy-to-interpret estimates of sensitivity, specificity and PTB prevalence under more realistic assumptions. Failure to fully account for diagnostic test dependence can yield misleading inferences