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Papers by Julitha Molepo
SADJ : journal of the South African Dental Association = tydskrif van die Suid-Afrikaanse Tandheelkundige Vereniging, 2012
C. albicans undergoes phenotypic switchng, a putative virulence trait assisting the organism to a... more C. albicans undergoes phenotypic switchng, a putative virulence trait assisting the organism to adapt to different environments. Although this switching has been studied among C. albicans isolates, not much is known about the process among various C. albicans clades (a group of genetic variants within a single species). To determine whether phenotypic switching among fluconazole resistant C. albicans isolates is clade-related. Fifteen fluconazole resistant C. albicans isolates from different clades were studied. Phenotypic switching was determined by a method previously described. Switching behaviour and different colony morphologies among different clades were compared. Phenotypic switching was observed in all clades, with clade SA exhibiting the most switching (75%), and clade NG the east (5.6%). Stipple was the most dominant phenotype observed in all clades (p = 0.024), occurring mostly in clade SA (35%). Irregular wrinkle phenotype was dominant in clade SA (62%). Phenotypic swit...
AIM: To evaluate microbial contamination of toothbrushes and the efficacy of different oral disin... more AIM: To evaluate microbial contamination of toothbrushes and the efficacy of different oral disinfectant agents in their decontamination METHODS: The heads of 98 used toothbrushes derived from patients who needed oral hygiene treatment were included in the study. In the laboratory, microorganisms on toothbrush heads were identified using standard microbiological methods. Toothbrush heads with microorganisms were then randomly divided into four groups of 19 and disinfected with Brushtox, Andolex C, Listerine® and water (control), followed by microbiological analysis RESULTS: Seventy eight percent of toothbrushes were contaminated with different microorganisms. Coagulase-negative staphylococci (CoNS) were found in a high number of toothbrushes (49%), followed by Pseudomonas spp (37%), Staphylococcus aureus (32%), Streptococcus mutans (14%), coliforms (9%) and Candida albicans (3%). Decontamination of toothbrushes with Andolex C and Listerine® reduced the number of contaminated toothbr...
South African Dental Journal, 2017
Introduction: Pacifiers used by toddlers and young children are susceptible to contamination by m... more Introduction: Pacifiers used by toddlers and young children are susceptible to contamination by microorganisms. Effective methods of disinfection are required to prevent oral infections. There are limited studies on pacifier disinfection in South Africa. aim: To investigate the efficacy of four pacifier disinfecting agents. Methods: Two groups of 80 pacifiers each were contaminated with a standardized suspension of either Staphylococcus epidermidis or Candida parapsilosis. Each group was subdivided into four subgroups , and severally disinfected with 0.12% GUM ® Paroex™ Chlorhexidine Gluconate Oral Rinse (chlorhexidine), Brushtox ® , apple cider vinegar and sterile distilled water (control), followed by microbiological analysis. Data were analyzed using the Kruskal Wallis Anova test. results: Chlorhexidine and Brushtox ® were statistically similar in eliminating the fungi from pacifiers (p>0.05). Statistically significant differences were noted between the effects of chlorhexidine and Brushtox ® compared with that of apple cider vinegar for both test organisms (p=0.0001). Statistically significant differences were observed in the efficacies of disinfection between chlorhexidine, Brushtox ® , apple cider vinegar and sterile distilled water (p=0.00089). conclusion: Chlorhexidine and Brushtox ® were equally effective in eliminating both S. epidermidis and C. parapsilosis from silicone pacifiers. Apple cider vinegar was the least effective disinfecting solution.
AIM: To evaluate microbial contamination of toothbrushes and the efficacy of different oral disin... more AIM: To evaluate microbial contamination of toothbrushes and the efficacy of different oral disinfectant agents in their decontamination METHODS: The heads of 98 used toothbrushes derived from patients who needed oral hygiene treatment were included in the study. In the laboratory, microorganisms on toothbrush heads were identified using standard microbiological methods. Toothbrush heads with microorganisms were then randomly divided into four groups of 19 and disinfected with Brushtox, Andolex C, Listerine® and water (control), followed by microbiological analysis RESULTS: Seventy eight percent of toothbrushes were contaminated with different microorganisms. Coagulase-negative staphylococci (CoNS) were found in a high number of toothbrushes (49%), followed by Pseudomonas spp (37%), Staphylococcus aureus (32%), Streptococcus mutans (14%), coliforms (9%) and Candida albicans (3%). Decontamination of toothbrushes with Andolex C and Listerine® reduced the number of contaminated toothbr...
Introduction: Whilst in use as comforting devices, the nipples of pacifiers are permanently in co... more Introduction: Whilst in use as comforting devices, the nipples of pacifiers are permanently in contact with normal oral flora and saliva, allowing flourishing bacterial biofilms. Effective disinfection will limit contamination, promote oral health and prevent oral infections in children. Studies on pacifier disinfection in South Africa are not well documented. Aim: To investigate in vitro disinfection of contaminated pacifiers with alcohol-free oral rinse and microwave. Methods: Seventy two silicone pacifiers were divided into two groups of 36, and contaminated with standardized suspensions of Candida albicans and Streptococcus mutans respectively. Each group was subdivided into three and disinfected with alcohol-free oral rinse, microwave and sterile distilled water (control), followed by microbiological analysis. Data was analyzed using Kruskal Wallis Anova test. Results: Alcohol-free oral rinse removed S. mutans from 42% of pacifiers, whilst microwave removed 33%. Microwave remov...
I, Julitha Molepo, hereby declare that the work on which this thesis is based, is original (excep... more I, Julitha Molepo, hereby declare that the work on which this thesis is based, is original (except where acknowledgements indicate otherwise) and that neither the whole work, nor any part of it has been, is being, or is to be submitted for another degree at this or any other university or tertiary education, institution or examination body.
South African Dental Journal
Denture stomatitis, mainly caused by Candida albicans, often affect denture wearers. To manage th... more Denture stomatitis, mainly caused by Candida albicans, often affect denture wearers. To manage these patients, denture hygiene is of utmost importance. There is a need for low cost, easily accessible denture disinfectants. To investigate the efficacy of rice vinegar and other disinfecting solutions in removing C. albicans from acrylic resins. Hundred and eighty acrylic resin plates were contaminated with C. albicans strains and divided into five groups. These were immersed in apple cider vinegar (ACV), white wine vinegar (WWV), rice vinegar (RV), chlorhexidine (CHX), and sterile distilled H2O (control). The plates were incubated at room temperature for 30 minutes, 1 hour and 8 hours. Candida removing ability of the disinfecting solutions was evaluated, and data was analyzed using two-way ANOVAwith Tukey post-test. Significance level of p< 0.05 was used. RV, ACV, WWV and CHX showed the highest efficacy (100%) in removing both C. albicans strains at 8 hours (p>0.05). CHX was the...
South African Dental Journal
The SADJ is licensed under Creative Commons Licence CC-BY-NC-4.0. Head and neck space infections ... more The SADJ is licensed under Creative Commons Licence CC-BY-NC-4.0. Head and neck space infections remain one of the most commonly encountered conditions at Maxillofacial clinics countrywide. Patients admitted with these infections tend to have prolonged hospital stays and often require intensive care support. This places financial and logistic constraints on our health care system. There are also growing concerns, worldwide, regarding antibiotic resistance. To determine the microbial spectrum of head and neck space infections in patients admitted to the Maxillo-Facial clinic at Livingstone Hospital in the Eastern Cape over a period of 5 years. Demographic, clinical and laboratory data was retrieved from the medical records of 140 patients presenting with head and neck space infections. Most patients were males aged 21-40 years. The most common cause of head and neck infections was nonodontogenic. The submandibular space was the most commonly implicated. Gram positive facultative anaerobes were most commonly identified. Bacteroides species and Staphylococcus aureus displayed sensitivity to clindamycin and amoxicillin with clavulanic acid. Viridans streptococci were sensitive to both penicillin and clindamycin. Bacteroides species were the most commonly isolated bacteria, followed by Viridans streptococci and Staphylococcus aureus. Patients admitted with deep space head and neck infections tend to have prolonged hospital stays and often require intensive care support, which places financial and logistic constraints on our health care system. There are also growing concerns, worldwide, regarding antibiotic resistance. Several studies reported that odontogenic infections were identified as the most common source of head and neck infections. 1-3 Infiltration through fascial spaces is an important factor to consider in the evaluation of head and neck space infections. The submandibular space was the most frequently involved fascial space in both single 4-8 and multiple space infections. 2,3 Head and neck space infections are caused by both aerobic and anaerobic microorganisms. The most frequently isolated aerobic bacterium was Streptococcus viridans 6 while Bacteroides was the most common anaerobic bacterium. 3,8 Molomo et al. 5 and Cabral et al. 9 reported Staphylococcus aureus to be the most commonly isolated organism. Effective management consists of surgical drainage and the administration of the appropriate antibiotic. Staphylococcus aureus, Streptococcus mitis/oralis and Morganella morganii displayed high resistance levels against amoxicillin. 7,10 Amoxicillin with clavulanic acid was reported as the most effective antibiotic for the most commonly isolated organisms, 7 therefore it was recommended as the empirical drug of choice in head and neck space infections. 7,8 This study focussed on the microbial spectrum and antibiotic sensitivity patterns in patients with head and neck space infections over a 5 year period, in order to
European Journal of Dental Education
BACKGROUND The Dental Materials (DM) course was introduced as a stand-alone course in 2013, at th... more BACKGROUND The Dental Materials (DM) course was introduced as a stand-alone course in 2013, at the University. Prior to that, DM was integrated into clinical courses. OBJECTIVE To determine the perceptions of the Bachelor of Dental Science (BDS2 to BDS5) students on a stand-alone DM course following curricular amendment. METHODS This was a cross-sectional study, in which a simple random sampling strategy was used, with forty-six students participating. The study was conducted in 2017. A self-administered, structured, validated questionnaire was used to collect data. The obtained data were summarized and analysed using descriptive and inferential statistics (one-way ANOVA). RESULTS The study was conducted on Bachelor of Dental Science (BDS2 to BDS5) students. A response rate of 49% from the administered questionnaires was achieved. The overall perception, total mean percentage score of 71.4% was obtained showing a generally positive view on the relevance of the course by students. A total mean percentage score of 74.1% showed the students' view that the DM course was well managed while a total mean score of 56.7% expressed the overall view on the reintegration of DM into clinical courses. CONCLUSION The students felt that DM was relevant and it could continue as a stand-alone course. They perceived that the course was run effectively and managed well but they had conflicting views on reintegration of the course into clinical modules. Studies with larger sample sizes at other Dental Schools are recommended to determine similarity of results.
African Journal of Laboratory Medicine
Background: The diagnosis of pleural tuberculosis remains a challenge, because the most widely us... more Background: The diagnosis of pleural tuberculosis remains a challenge, because the most widely used conventional diagnostic tools are unable to rapidly detect Mycobacterium tuberculosis in pleural fluid with sufficient sensitivity.Objectives: The aim of this study was to evaluate the usefulness of an adenosine deaminase assay and real-time polymerase chain reaction (qPCR) in diagnosing pleural tuberculosis.Methods: One hundred and five consecutive pleural fluid specimens collected between August 2008 and March 2009 were assessed. Among the 105 specimens, 50 (48%) were unconfirmed tuberculosis cases, 21 (20%) were confirmed tuberculosis cases and 34 (32%) were non-tuberculosis cases (controls). Real-time PCR was performed using the Light Cycler Mycobacterium detection kit according to the manufacturer‘s instructions (Roche Diagnostics). An adenosine deaminase assay was carried out using a commercial colorimetric assay kit as a user-defined method on a Beckman DxC 600 Synchron analyse...
Access Microbiology
The incidences of Candida albicans infections and their changing drug resistance patterns have dr... more The incidences of Candida albicans infections and their changing drug resistance patterns have drastically increased in recent years. Therefore, new drugs and alternative treatment strategies are promptly required. Combination therapy and the use of natural products have been extensively studied as alternative treatment. In this study, we synthesized Eugenol Tosylate Congeners (ETCs 1–6) and evaluated their antifungal activity profile alone and in combination with fluconazole (FLC) against four FLC susceptible and three FLC resistant clinical isolates of Candida albicans isolates according to CLSI guidelines. For insight mechanism of antifungal action of ETCs, activity of plasma membrane H+-ATPase pump of these C. albicans isolates was determined by monitoring the pH of the external medium. ETC 1 and ETC 4 were the most active congeners against the resistant isolates with the MIC ranging from 125 to 250 µg ml−1. The MFC of ETCs ranged from 1000 µg ml−1 to 2000 µg ml−1. Results interpreted from fractional inhibitory concentration index (FICI) and isobolograms showed 36 % of synergy, 29 % of additive, 33 % of indifferent and 2 % of antagonistic interactions. These compounds also inhibit H+efflux activity of H+-ATPase pump at varying degrees. Our results suggest that these ETCs may be directly binding to this pump and thereby inhibiting H+-efflux in Candida cells. These results advocate the potential of these compounds in developing new antifungal drugs; however, further studies are required to understand the other mechanisms involved and in vivo efficacy and toxicity of these compounds.
Current pharmaceutical design, Jan 6, 2016
Infections caused by Candida have become a major source of morbidity and mortality. Limited numbe... more Infections caused by Candida have become a major source of morbidity and mortality. Limited numbers of drugs are available to treat these infections. Phytochemicals can be the major source of antifungal compounds. The aim of this publication was to review the current literature to assess the challenges and scope of phytochemical research in the development of new antifungal drugs. Literature describing cellular nature of Candida, the development of drug resistance and target sites for the new drugs were assessed. Publications reporting antifungal activities of crude extracts of plants, their essential oils and identified chemical constituents were also summarised. The results showed that the development of new antifungal agents from natural sources is a complex process due to the cellular nature of Candida and the types of infections caused, such as superficial to life threatening systemic mycosis which necessitate systemic and topical use of drugs. Efficacy of the drugs in the pres...
Southern African Journal of Infectious Diseases, 2015
PLOS ONE, 2015
We previously reported the antifungal properties of a monoterpene phenol "Eugenol" against differ... more We previously reported the antifungal properties of a monoterpene phenol "Eugenol" against different Candida strains and have observed that the addition of methyl group to eugenol drastically increased its antimicrobial potency. Based on the results and the importance of medicinal synthetic chemistry, we synthesized eugenol-tosylate and its congeners (E1-E6) and tested their antifungal activity against different clinical fluconazole (FLC)-susceptible and FLC-resistant C. albicans isolates alone and in combination with FLC by determining fractional inhibitory concentration indices (FICIs) and isobolograms calculated from microdilution assays. Minimum inhibitory concentration (MIC) results confirmed that all the tested C. albicans strains were variably susceptible to the semi-synthetic derivatives E1-E6, with MIC values ranging from 1-62 μg/ml. The test compounds in combination with FLC exhibited either synergy (36%), additive (41%) or indifferent (23%) interactions, however, no antagonistic interactions were observed. The MICs of FLC decreased 2-9 fold when used in combination with the test compounds. Like their precursor eugenol, all the derivatives showed significant impairment of ergosterol biosynthesis in all C. albicans strains coupled with down regulation of the important ergosterol biosynthesis pathway gene-ERG11. The results were further validated by docking studies, which revealed that the inhibitors snugly fitting the active site of the target enzyme, mimicking fluconazole, may well explain their excellent inhibitory activity. Our results suggest that these compounds have a great potential as antifungals, which can be used as chemosensitizing agents with the known antifungal drugs.
Journal of Endodontics
This study compared the micro-leakage of a root canal filled with Resilon or gutta-percha (GP), u... more This study compared the micro-leakage of a root canal filled with Resilon or gutta-percha (GP), utilizing either cold lateral condensation or System B. Four experimental groups were used. Group one was obturated with GP using cold lateral condensation, group two with GP using System B, group three with Resilon using cold lateral condensation, and group four with Resilon using System B. Micro-leakage was tested using a two-chamber bacterial method as well as a dye penetration test. Data was subjected to statistical analysis using an ANOVA. A p-value <0.05 was considered as significant. The bacterial micro-leakage test showed no significant difference between GP and Resilon when using Cold Lateral condensation (p = 0.2695) or System B (p = 0.5602). The dye penetration test also showed no significant difference between GP and Resilon using either the Cold Lateral condensation (p = 0.2713) or the System B techniques (p = 0.0767). The ability of GP and Resilon to seal a root canal is ...
Sexually Transmitted Diseases, 2010
Resurgence of syphilis in Canada and worldwide requires laboratories to update their methods for ... more Resurgence of syphilis in Canada and worldwide requires laboratories to update their methods for molecular epidemiology investigation and surveillance. This study utilizes polymerase chain reaction diagnostic tests for syphilis, identifies macrolide resistance, and uses a molecular typing system to characterize Treponema pallidum clinical strains causing syphilis in Alberta and Northwest Territories, Canada. In total 449 specimens including genital swabs, whole blood, sera, and cerebrospinal fluid were obtained from 374 patients with suspect syphilis in Alberta and Northwest Territories. Molecular subtyping was based on genetic characterization of treponemal repeat genes, arp and tpr. Detection of macrolide resistance was accomplished by identification of the 23S rRNA gene mutation associated with the resistance pattern. Forty-nine specimens obtained from 43 patients were found to be positive for T. pallidum DNA using bmp, tpp47 and polA polymerase chain reaction assays. Four molecular subtypes were identified, with one type, 14d, accounting for 70% of all cases and 83% of typeable strains. Seven patients (16%) were found to be infected by macrolide-resistant strains, of which 6 were men who have sex with men and 1 whose infection was acquired in China. A single molecular type of T. pallidum, characterized as 14d, caused the majority of the syphilis cases identified in this study. A more discriminatory typing method would be required to determine if these strains are clonal. Treatment of infectious syphilis with macrolide antibiotics should be restricted to patient populations where resistance is rare and clinical and serological follow up of patients is possible.
Diagnostic microbiology and infectious disease, 2005
Molecular epidemiology revealed 5 distinct clades among clinical isolates of Candida albicans, us... more Molecular epidemiology revealed 5 distinct clades among clinical isolates of Candida albicans, using DNA fingerprinting with the complex Ca3 probe. Certain clades were found to be highly enriched in particular geographical areas (e.g., clade E in Europe and clade SA in South Africa, whereas clade II is completely absent in the southwest United States). From fingerprinting data, it is concluded that little interclade recombination takes place, and therefore, it would not be unusual to expect clade-specific phenotypic characteristics. The first clade-related phenotypic difference was found with 5-flucytosine resistance being almost exclusively restricted to clade I. When in vitro antifungal susceptibility testing revealed 8.4% of South African oral yeast isolates to be naturally resistant to amphotericin B, it was decided to investigate a possible clade relationship for this relatively high resistance. Thirty-eight amphotericin B-resistant C. albicans isolates were fingerprinted, and ...
SADJ : journal of the South African Dental Association = tydskrif van die Suid-Afrikaanse Tandheelkundige Vereniging, 2012
C. albicans undergoes phenotypic switchng, a putative virulence trait assisting the organism to a... more C. albicans undergoes phenotypic switchng, a putative virulence trait assisting the organism to adapt to different environments. Although this switching has been studied among C. albicans isolates, not much is known about the process among various C. albicans clades (a group of genetic variants within a single species). To determine whether phenotypic switching among fluconazole resistant C. albicans isolates is clade-related. Fifteen fluconazole resistant C. albicans isolates from different clades were studied. Phenotypic switching was determined by a method previously described. Switching behaviour and different colony morphologies among different clades were compared. Phenotypic switching was observed in all clades, with clade SA exhibiting the most switching (75%), and clade NG the east (5.6%). Stipple was the most dominant phenotype observed in all clades (p = 0.024), occurring mostly in clade SA (35%). Irregular wrinkle phenotype was dominant in clade SA (62%). Phenotypic swit...
AIM: To evaluate microbial contamination of toothbrushes and the efficacy of different oral disin... more AIM: To evaluate microbial contamination of toothbrushes and the efficacy of different oral disinfectant agents in their decontamination METHODS: The heads of 98 used toothbrushes derived from patients who needed oral hygiene treatment were included in the study. In the laboratory, microorganisms on toothbrush heads were identified using standard microbiological methods. Toothbrush heads with microorganisms were then randomly divided into four groups of 19 and disinfected with Brushtox, Andolex C, Listerine® and water (control), followed by microbiological analysis RESULTS: Seventy eight percent of toothbrushes were contaminated with different microorganisms. Coagulase-negative staphylococci (CoNS) were found in a high number of toothbrushes (49%), followed by Pseudomonas spp (37%), Staphylococcus aureus (32%), Streptococcus mutans (14%), coliforms (9%) and Candida albicans (3%). Decontamination of toothbrushes with Andolex C and Listerine® reduced the number of contaminated toothbr...
South African Dental Journal, 2017
Introduction: Pacifiers used by toddlers and young children are susceptible to contamination by m... more Introduction: Pacifiers used by toddlers and young children are susceptible to contamination by microorganisms. Effective methods of disinfection are required to prevent oral infections. There are limited studies on pacifier disinfection in South Africa. aim: To investigate the efficacy of four pacifier disinfecting agents. Methods: Two groups of 80 pacifiers each were contaminated with a standardized suspension of either Staphylococcus epidermidis or Candida parapsilosis. Each group was subdivided into four subgroups , and severally disinfected with 0.12% GUM ® Paroex™ Chlorhexidine Gluconate Oral Rinse (chlorhexidine), Brushtox ® , apple cider vinegar and sterile distilled water (control), followed by microbiological analysis. Data were analyzed using the Kruskal Wallis Anova test. results: Chlorhexidine and Brushtox ® were statistically similar in eliminating the fungi from pacifiers (p>0.05). Statistically significant differences were noted between the effects of chlorhexidine and Brushtox ® compared with that of apple cider vinegar for both test organisms (p=0.0001). Statistically significant differences were observed in the efficacies of disinfection between chlorhexidine, Brushtox ® , apple cider vinegar and sterile distilled water (p=0.00089). conclusion: Chlorhexidine and Brushtox ® were equally effective in eliminating both S. epidermidis and C. parapsilosis from silicone pacifiers. Apple cider vinegar was the least effective disinfecting solution.
AIM: To evaluate microbial contamination of toothbrushes and the efficacy of different oral disin... more AIM: To evaluate microbial contamination of toothbrushes and the efficacy of different oral disinfectant agents in their decontamination METHODS: The heads of 98 used toothbrushes derived from patients who needed oral hygiene treatment were included in the study. In the laboratory, microorganisms on toothbrush heads were identified using standard microbiological methods. Toothbrush heads with microorganisms were then randomly divided into four groups of 19 and disinfected with Brushtox, Andolex C, Listerine® and water (control), followed by microbiological analysis RESULTS: Seventy eight percent of toothbrushes were contaminated with different microorganisms. Coagulase-negative staphylococci (CoNS) were found in a high number of toothbrushes (49%), followed by Pseudomonas spp (37%), Staphylococcus aureus (32%), Streptococcus mutans (14%), coliforms (9%) and Candida albicans (3%). Decontamination of toothbrushes with Andolex C and Listerine® reduced the number of contaminated toothbr...
Introduction: Whilst in use as comforting devices, the nipples of pacifiers are permanently in co... more Introduction: Whilst in use as comforting devices, the nipples of pacifiers are permanently in contact with normal oral flora and saliva, allowing flourishing bacterial biofilms. Effective disinfection will limit contamination, promote oral health and prevent oral infections in children. Studies on pacifier disinfection in South Africa are not well documented. Aim: To investigate in vitro disinfection of contaminated pacifiers with alcohol-free oral rinse and microwave. Methods: Seventy two silicone pacifiers were divided into two groups of 36, and contaminated with standardized suspensions of Candida albicans and Streptococcus mutans respectively. Each group was subdivided into three and disinfected with alcohol-free oral rinse, microwave and sterile distilled water (control), followed by microbiological analysis. Data was analyzed using Kruskal Wallis Anova test. Results: Alcohol-free oral rinse removed S. mutans from 42% of pacifiers, whilst microwave removed 33%. Microwave remov...
I, Julitha Molepo, hereby declare that the work on which this thesis is based, is original (excep... more I, Julitha Molepo, hereby declare that the work on which this thesis is based, is original (except where acknowledgements indicate otherwise) and that neither the whole work, nor any part of it has been, is being, or is to be submitted for another degree at this or any other university or tertiary education, institution or examination body.
South African Dental Journal
Denture stomatitis, mainly caused by Candida albicans, often affect denture wearers. To manage th... more Denture stomatitis, mainly caused by Candida albicans, often affect denture wearers. To manage these patients, denture hygiene is of utmost importance. There is a need for low cost, easily accessible denture disinfectants. To investigate the efficacy of rice vinegar and other disinfecting solutions in removing C. albicans from acrylic resins. Hundred and eighty acrylic resin plates were contaminated with C. albicans strains and divided into five groups. These were immersed in apple cider vinegar (ACV), white wine vinegar (WWV), rice vinegar (RV), chlorhexidine (CHX), and sterile distilled H2O (control). The plates were incubated at room temperature for 30 minutes, 1 hour and 8 hours. Candida removing ability of the disinfecting solutions was evaluated, and data was analyzed using two-way ANOVAwith Tukey post-test. Significance level of p< 0.05 was used. RV, ACV, WWV and CHX showed the highest efficacy (100%) in removing both C. albicans strains at 8 hours (p>0.05). CHX was the...
South African Dental Journal
The SADJ is licensed under Creative Commons Licence CC-BY-NC-4.0. Head and neck space infections ... more The SADJ is licensed under Creative Commons Licence CC-BY-NC-4.0. Head and neck space infections remain one of the most commonly encountered conditions at Maxillofacial clinics countrywide. Patients admitted with these infections tend to have prolonged hospital stays and often require intensive care support. This places financial and logistic constraints on our health care system. There are also growing concerns, worldwide, regarding antibiotic resistance. To determine the microbial spectrum of head and neck space infections in patients admitted to the Maxillo-Facial clinic at Livingstone Hospital in the Eastern Cape over a period of 5 years. Demographic, clinical and laboratory data was retrieved from the medical records of 140 patients presenting with head and neck space infections. Most patients were males aged 21-40 years. The most common cause of head and neck infections was nonodontogenic. The submandibular space was the most commonly implicated. Gram positive facultative anaerobes were most commonly identified. Bacteroides species and Staphylococcus aureus displayed sensitivity to clindamycin and amoxicillin with clavulanic acid. Viridans streptococci were sensitive to both penicillin and clindamycin. Bacteroides species were the most commonly isolated bacteria, followed by Viridans streptococci and Staphylococcus aureus. Patients admitted with deep space head and neck infections tend to have prolonged hospital stays and often require intensive care support, which places financial and logistic constraints on our health care system. There are also growing concerns, worldwide, regarding antibiotic resistance. Several studies reported that odontogenic infections were identified as the most common source of head and neck infections. 1-3 Infiltration through fascial spaces is an important factor to consider in the evaluation of head and neck space infections. The submandibular space was the most frequently involved fascial space in both single 4-8 and multiple space infections. 2,3 Head and neck space infections are caused by both aerobic and anaerobic microorganisms. The most frequently isolated aerobic bacterium was Streptococcus viridans 6 while Bacteroides was the most common anaerobic bacterium. 3,8 Molomo et al. 5 and Cabral et al. 9 reported Staphylococcus aureus to be the most commonly isolated organism. Effective management consists of surgical drainage and the administration of the appropriate antibiotic. Staphylococcus aureus, Streptococcus mitis/oralis and Morganella morganii displayed high resistance levels against amoxicillin. 7,10 Amoxicillin with clavulanic acid was reported as the most effective antibiotic for the most commonly isolated organisms, 7 therefore it was recommended as the empirical drug of choice in head and neck space infections. 7,8 This study focussed on the microbial spectrum and antibiotic sensitivity patterns in patients with head and neck space infections over a 5 year period, in order to
European Journal of Dental Education
BACKGROUND The Dental Materials (DM) course was introduced as a stand-alone course in 2013, at th... more BACKGROUND The Dental Materials (DM) course was introduced as a stand-alone course in 2013, at the University. Prior to that, DM was integrated into clinical courses. OBJECTIVE To determine the perceptions of the Bachelor of Dental Science (BDS2 to BDS5) students on a stand-alone DM course following curricular amendment. METHODS This was a cross-sectional study, in which a simple random sampling strategy was used, with forty-six students participating. The study was conducted in 2017. A self-administered, structured, validated questionnaire was used to collect data. The obtained data were summarized and analysed using descriptive and inferential statistics (one-way ANOVA). RESULTS The study was conducted on Bachelor of Dental Science (BDS2 to BDS5) students. A response rate of 49% from the administered questionnaires was achieved. The overall perception, total mean percentage score of 71.4% was obtained showing a generally positive view on the relevance of the course by students. A total mean percentage score of 74.1% showed the students' view that the DM course was well managed while a total mean score of 56.7% expressed the overall view on the reintegration of DM into clinical courses. CONCLUSION The students felt that DM was relevant and it could continue as a stand-alone course. They perceived that the course was run effectively and managed well but they had conflicting views on reintegration of the course into clinical modules. Studies with larger sample sizes at other Dental Schools are recommended to determine similarity of results.
African Journal of Laboratory Medicine
Background: The diagnosis of pleural tuberculosis remains a challenge, because the most widely us... more Background: The diagnosis of pleural tuberculosis remains a challenge, because the most widely used conventional diagnostic tools are unable to rapidly detect Mycobacterium tuberculosis in pleural fluid with sufficient sensitivity.Objectives: The aim of this study was to evaluate the usefulness of an adenosine deaminase assay and real-time polymerase chain reaction (qPCR) in diagnosing pleural tuberculosis.Methods: One hundred and five consecutive pleural fluid specimens collected between August 2008 and March 2009 were assessed. Among the 105 specimens, 50 (48%) were unconfirmed tuberculosis cases, 21 (20%) were confirmed tuberculosis cases and 34 (32%) were non-tuberculosis cases (controls). Real-time PCR was performed using the Light Cycler Mycobacterium detection kit according to the manufacturer‘s instructions (Roche Diagnostics). An adenosine deaminase assay was carried out using a commercial colorimetric assay kit as a user-defined method on a Beckman DxC 600 Synchron analyse...
Access Microbiology
The incidences of Candida albicans infections and their changing drug resistance patterns have dr... more The incidences of Candida albicans infections and their changing drug resistance patterns have drastically increased in recent years. Therefore, new drugs and alternative treatment strategies are promptly required. Combination therapy and the use of natural products have been extensively studied as alternative treatment. In this study, we synthesized Eugenol Tosylate Congeners (ETCs 1–6) and evaluated their antifungal activity profile alone and in combination with fluconazole (FLC) against four FLC susceptible and three FLC resistant clinical isolates of Candida albicans isolates according to CLSI guidelines. For insight mechanism of antifungal action of ETCs, activity of plasma membrane H+-ATPase pump of these C. albicans isolates was determined by monitoring the pH of the external medium. ETC 1 and ETC 4 were the most active congeners against the resistant isolates with the MIC ranging from 125 to 250 µg ml−1. The MFC of ETCs ranged from 1000 µg ml−1 to 2000 µg ml−1. Results interpreted from fractional inhibitory concentration index (FICI) and isobolograms showed 36 % of synergy, 29 % of additive, 33 % of indifferent and 2 % of antagonistic interactions. These compounds also inhibit H+efflux activity of H+-ATPase pump at varying degrees. Our results suggest that these ETCs may be directly binding to this pump and thereby inhibiting H+-efflux in Candida cells. These results advocate the potential of these compounds in developing new antifungal drugs; however, further studies are required to understand the other mechanisms involved and in vivo efficacy and toxicity of these compounds.
Current pharmaceutical design, Jan 6, 2016
Infections caused by Candida have become a major source of morbidity and mortality. Limited numbe... more Infections caused by Candida have become a major source of morbidity and mortality. Limited numbers of drugs are available to treat these infections. Phytochemicals can be the major source of antifungal compounds. The aim of this publication was to review the current literature to assess the challenges and scope of phytochemical research in the development of new antifungal drugs. Literature describing cellular nature of Candida, the development of drug resistance and target sites for the new drugs were assessed. Publications reporting antifungal activities of crude extracts of plants, their essential oils and identified chemical constituents were also summarised. The results showed that the development of new antifungal agents from natural sources is a complex process due to the cellular nature of Candida and the types of infections caused, such as superficial to life threatening systemic mycosis which necessitate systemic and topical use of drugs. Efficacy of the drugs in the pres...
Southern African Journal of Infectious Diseases, 2015
PLOS ONE, 2015
We previously reported the antifungal properties of a monoterpene phenol "Eugenol" against differ... more We previously reported the antifungal properties of a monoterpene phenol "Eugenol" against different Candida strains and have observed that the addition of methyl group to eugenol drastically increased its antimicrobial potency. Based on the results and the importance of medicinal synthetic chemistry, we synthesized eugenol-tosylate and its congeners (E1-E6) and tested their antifungal activity against different clinical fluconazole (FLC)-susceptible and FLC-resistant C. albicans isolates alone and in combination with FLC by determining fractional inhibitory concentration indices (FICIs) and isobolograms calculated from microdilution assays. Minimum inhibitory concentration (MIC) results confirmed that all the tested C. albicans strains were variably susceptible to the semi-synthetic derivatives E1-E6, with MIC values ranging from 1-62 μg/ml. The test compounds in combination with FLC exhibited either synergy (36%), additive (41%) or indifferent (23%) interactions, however, no antagonistic interactions were observed. The MICs of FLC decreased 2-9 fold when used in combination with the test compounds. Like their precursor eugenol, all the derivatives showed significant impairment of ergosterol biosynthesis in all C. albicans strains coupled with down regulation of the important ergosterol biosynthesis pathway gene-ERG11. The results were further validated by docking studies, which revealed that the inhibitors snugly fitting the active site of the target enzyme, mimicking fluconazole, may well explain their excellent inhibitory activity. Our results suggest that these compounds have a great potential as antifungals, which can be used as chemosensitizing agents with the known antifungal drugs.
Journal of Endodontics
This study compared the micro-leakage of a root canal filled with Resilon or gutta-percha (GP), u... more This study compared the micro-leakage of a root canal filled with Resilon or gutta-percha (GP), utilizing either cold lateral condensation or System B. Four experimental groups were used. Group one was obturated with GP using cold lateral condensation, group two with GP using System B, group three with Resilon using cold lateral condensation, and group four with Resilon using System B. Micro-leakage was tested using a two-chamber bacterial method as well as a dye penetration test. Data was subjected to statistical analysis using an ANOVA. A p-value <0.05 was considered as significant. The bacterial micro-leakage test showed no significant difference between GP and Resilon when using Cold Lateral condensation (p = 0.2695) or System B (p = 0.5602). The dye penetration test also showed no significant difference between GP and Resilon using either the Cold Lateral condensation (p = 0.2713) or the System B techniques (p = 0.0767). The ability of GP and Resilon to seal a root canal is ...
Sexually Transmitted Diseases, 2010
Resurgence of syphilis in Canada and worldwide requires laboratories to update their methods for ... more Resurgence of syphilis in Canada and worldwide requires laboratories to update their methods for molecular epidemiology investigation and surveillance. This study utilizes polymerase chain reaction diagnostic tests for syphilis, identifies macrolide resistance, and uses a molecular typing system to characterize Treponema pallidum clinical strains causing syphilis in Alberta and Northwest Territories, Canada. In total 449 specimens including genital swabs, whole blood, sera, and cerebrospinal fluid were obtained from 374 patients with suspect syphilis in Alberta and Northwest Territories. Molecular subtyping was based on genetic characterization of treponemal repeat genes, arp and tpr. Detection of macrolide resistance was accomplished by identification of the 23S rRNA gene mutation associated with the resistance pattern. Forty-nine specimens obtained from 43 patients were found to be positive for T. pallidum DNA using bmp, tpp47 and polA polymerase chain reaction assays. Four molecular subtypes were identified, with one type, 14d, accounting for 70% of all cases and 83% of typeable strains. Seven patients (16%) were found to be infected by macrolide-resistant strains, of which 6 were men who have sex with men and 1 whose infection was acquired in China. A single molecular type of T. pallidum, characterized as 14d, caused the majority of the syphilis cases identified in this study. A more discriminatory typing method would be required to determine if these strains are clonal. Treatment of infectious syphilis with macrolide antibiotics should be restricted to patient populations where resistance is rare and clinical and serological follow up of patients is possible.
Diagnostic microbiology and infectious disease, 2005
Molecular epidemiology revealed 5 distinct clades among clinical isolates of Candida albicans, us... more Molecular epidemiology revealed 5 distinct clades among clinical isolates of Candida albicans, using DNA fingerprinting with the complex Ca3 probe. Certain clades were found to be highly enriched in particular geographical areas (e.g., clade E in Europe and clade SA in South Africa, whereas clade II is completely absent in the southwest United States). From fingerprinting data, it is concluded that little interclade recombination takes place, and therefore, it would not be unusual to expect clade-specific phenotypic characteristics. The first clade-related phenotypic difference was found with 5-flucytosine resistance being almost exclusively restricted to clade I. When in vitro antifungal susceptibility testing revealed 8.4% of South African oral yeast isolates to be naturally resistant to amphotericin B, it was decided to investigate a possible clade relationship for this relatively high resistance. Thirty-eight amphotericin B-resistant C. albicans isolates were fingerprinted, and ...