Detection of Antimicrobial Compounds by Bioautography of Different Extracts of Leaves of Selected South African Tree Species

The hexane, acetone, dichloromethane and methanol extracts of Combretum vendae A.E. van Wyk (Combretaceae), Commiphora harveyi (Engl.) Engl. (Burseraceae), Khaya anthotheca (Welm.) C.DC (Meliaceae), Kirkia wilmsii Engl. (Kirkiaceae), Loxostylis alata A. Spreng. ex Rchb. (Anacardiaceae), Ochna natalitia (Meisn.) Walp. (Ochnaceae) and Protorhus longifolia (Bernh. Ex C. Krauss) Engl. (Anacardiaceae) were screened for their antimicrobial activity. The test organisms included bacteria (Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus), and fungi (Aspergillus fumigatus, Candida albicans, Cryptococcus neoformans, Microsporum canis and Sporothrix schenckii). A simple bioautographic procedure, involving spraying suspensions of the bacteria or fungi on thin layer chromatography (TLC) plates developed in solvents of varying polarities was used to detect the number of antibacterial and antifungal compounds present in the extracts. All the extracts had antimicrobial activity against at least one of the test microorganisms. This activity was denoted by white spots against a red-purple background on the TLC plates after spraying with tetrazolium violet. Twenty seven TLC plates; 9 for each solvent system and 3 different solvent systems per organism were tested in the bioautographic procedure. Of the bacteria tested, S. aureus was inhibited by the most compounds separated on the TLC plates from all the tested plants. Similarly, growth of the fungus C. neoformans was also inhibited by many compounds present in the extracts. Loxostylis alata appeared to be the plant extract with the highest number of inhibition bands when compared with other plants tested against both bacteria and fungi. This species was selected for in depth further study.     

Carotid stenosis after adjuvant cervical radiotherapy in patients with head and neck cancers: a prospective controlled study

Clin. Otolaryngol. 2012, 37 , 376–381 Objectives: To determine the prevalence of radiation‐induced carotid stenosis, in patients who were treated for head and neck malignancies, using colour‐flow duplex scanning. Design: Prospective controlled study at a single medical centre. Participants: We enrolled two groups of patients. The first (radiotherapy group) consisted of patients who received surgical treatment and adjuvant radiotherapy of the neck. The control group consisted of patients with head and neck malignancies who received only surgical treatment. Main outcome measures: All patients were evaluated with carotid artery ecoDoppler imaging 1 week before and 36 months after the surgical procedure. Intima‐media thickness was measured bilaterally at the internal carotid artery and at the bifurcation. Carotid obstruction was classified as low (0–30%), moderate (31–49%) or severe (≥50%). Results: The preoperative stenosis grade did not differ between groups. In 15/25 patients (60%) in the radiotherapy group, mild stenosis evolved to moderate stenosis, while only 6/37 (16%) of the controls did (P = 0.004). Additionally, 9/39 (23%) patients in the radiotherapy group progressed to severe stenosis compared with only 3/54 (6%) controls (P = 0.029). The overall evolution showed that stenosis worsened in 24/32 (62%) patients in the radiotherapy group and 9/54 (17%) patients in the control groups (P < 0.0001). Conclusions: These results highlight the need to study the long‐term incidence of cerebrovascular events in these two different populations (radiation treated and surgically treated) to identify increased cerebrovascular morbidity.     

REVIEW ARTICLE: Paediatric nasopharyngeal rhabdomyosarcoma: A case series and literature review

Rhabdomyosarcoma (RMS) is the most common soft tissue tumour in children, with the head and neck region accounting for 35–40% of cases. Nasopharyngeal RMSs tend to grow rapidly and invade adjacent structures. Both the Intergroup Rhabdomyosarcoma Studies and the European Studies have established that the ideal management of this disease is multimodal, using a combination of surgery, chemotherapy and radiotherapy. This case series examines the role of radiotherapy in the management of paediatric nasopharyngeal RMSs, with particular reference to long-term morbidity and disease-free survival. The cases of five children with nasopharyngeal RMS were reviewed and a systematic review of the literature contained in the PubMed databases was conducted to establish 24 individually detailed cases. Management in all patients was multimodal, using a combination of chemotherapy, radiotherapy as well as surgery. External beam radiotherapy is an integral component of treatment for nasopharyngeal RMSs. With more patients surviving for longer periods, more long-term sequelae of radiotherapy have been reported. Complications include sensorineural deafness, endocrine manifestations following radiation of the pituitary gland, cranial nerve palsies, second malignancies within the radiation field, cataract formation, retinopathy and growth disturbance. Morbidity from radiotherapy may be considerable and depends on the field and dose of radiation. Current advances in radiotherapy are aimed at improving the rate of tumour control and reducing such complications. Recent improvements in imaging and conformal techniques have the potential to reduce the morbidity associated with radiotherapy in this cohort.     

Identification and Assessment of Public Health Surveillance Gaps under the IHR (2005)

Objective

To conceive and develop a model to identify gaps in public health surveillance performance and provide a toolset to assess interventions, cost, and return on investment (ROI).

Introduction

Under the revised International Health Regulations (IHR [2005]) one of the eight core capacities is public health surveillance. In May 2012, despite a concerted effort by the global community, the World Health Organization (WHO) reported out that a significant number of member states would not achieve targeted capacity in the IHR (2005) surveillance core capacity.Currently, there is no model to identify and measure these gaps in surveillance performance. Likewise, there is no toolset to assess interventions by cost and estimate the ROI.We developed a new conceptual framework that: (1) described the work practices to achieve effective and efficient public health surveillance; (2) could identify impediments or gaps in performance; and (3) will assist program managers in decision making.

Methods

Published articles and grey-literature reports, manuals and logic model examples were gathered through a literature review of PubMed, Web of Science, Google Scholar, and other databases. Logic models were conceived by categorizing discrete surveillance inputs, activities, outputs, and outcomes. Indicators were selected from authoritative sources or developed and then mapped to the logic model elements. These indicators will be weighted using the principle component analysis (PCA), a method for enhanced precision of statistical analysis. Finally, on the front end of the tool, indicators will graphically measure the surveillance gap expressed through the tool’s architecture and provide information using an integrated cost-impact analysis.

Results

We developed five public health surveillance logic models: for IHR (2005) compliance; event-based; indicator-based; syndromic; and predictive surveillance domains. The IHR (2005) domain focused on national-level functionality, and the others described the complexities of their specific surveillance work practices. Indicators were then mapped and linked to all logic model elements.

Conclusions

This new framework, intended for self-administration at the national and subnational levels, measured public health surveillance gaps in performance and provided cost and ROI information by intervention. The logic model framework and PCA methodology are tools that both describe work processes and define appropriate variables used for evaluation. However, both require real-world data. We recommend pilot testing and validation of this new framework. Once piloted, the framework could be adapted for the other IHR (2005) core capacities.     

Evaluation of the apical seal in root canals prepared with a new rotary system and obturated with a methacrylate based endodontic sealer: an in vitro study

The purpose of this study was to evaluate in vitro the apical seal of root canals prepared with a new rotary system, Anatomic Endodontic Technology (AET) and filled with a methacrylate based endodontic sealer and a single gutta-percha cone and a lateral condensation technique, using the methacrylate based endodontic sealer/filler or Grossman's cement. The root canals of 45 freshly extracted human maxillary anterior teeth were prepared and then randomly assigned to three groups of 15 teeth each. After cleaning and shaping the teeth were obturated as follows: in group 1 the canals were filled with a methacrylate based sealer and a single gutta-percha cone; in group 2 the canals were filled using a lateral condensation technique with gutta-percha and the methacrylate based sealer; and in group 3, the canals were filled by means of lateral condensation of gutta-percha and Grossman's cement (control group). The specimens were stored in 100% relative humidity at 37 degrees C for 72 h, after which the coronal portion and the root surface of each tooth was covered with three layers of nail varnish and a final layer of sticky wax. After immersion in 2% methylene blue dye for 7 days, the specimens were imbedded in clear orthodontic resin and sectioned. Dye penetration was evaluated by an independent investigator using a stereo microscope. The results demonstrated that more pronounced leakage occurred in root canals obturated with the lateral condensation technique and Grossman's cement (p < 0.05). The least amount of dye leakage was observed for group 1 and 2 in which the methacrylate based sealer was used, either with a single gutta-percha cone or with lateral condensation of gutta-percha.     

Differences in neointima formation between impervious and porous polytetrafluoroethylene vascular patch material

The aim of this study was to compare the neointima formation and blood loss of an impervious ePTFE with those of the porous ePTFE patch. Ten mongrel dogs were selected for the study. Both the impervious and porous ePTFE patches were implanted into the common iliac arteries in each dog. The blood loss of each patch was recorded and the patches were explanted 30-60 days later for microscopic analysis. The arteries with either the impervious or the porous ePTFE patch were all patent at the end of the study. The impervious ePTFE patch had a significant reduction in blood loss when compared with the porous ePTFE patch (p = 0.04). The neointima covering both patches showed no statistically significant difference in its thickness or in its cellular composition. It has been speculated that wall porosity is essential for tissue ingrowth, endothelial cell proliferation, and neointima formation. In this study, the impervious ePTFE patch did not inhibit neointima formation. Our study shows that graft porosity does not improve neointima formation or patency. Neointimization of the impervious ePTFE patch is the result of pannus ingrowth and deposition of circulating blood elements. There is a statistically significant reduction in blood loss (p = 0.04) with impervious ePTFE patch, compared with that of the porous ePTFE patch.