Tonnie K Mulli

Involvement of Autoimmunity in the Pathogenesis of Aggressive Periodontitis

The aim of this study was to investigate the involvement of autoimmune reactions to native and post-translationally modified extracellular matrix components in the pathogenesis of periodontitis. Sera from individuals with aggressive periodontitis (AgP, n = 25), chronic periodontitis (CP, n = 14), and gingivitis (G, n = 18) were tested for the presence of autoantibodies against: (a) native collagen type I (CI) and collagen type III (CIII); (b) CI and CIII post-translationally modified by reactive oxygen species (ROS) of the type present during inflammation; and (c) citrullinated filaggrin-derived peptides (CCP). Autoantibodies to native and ROS-modified CI and CIII as well as autoantibodies to CCP were observed exclusively in patients with AgP and not in those with CP or G. In conclusion, autoimmune reactions to native and post-translationally modified self-antigens may play a role specifically in the pathogenesis of AgP.

Transcriptomic analysis of three Veillonella spp. present in carious dentine and in the saliva of caries-free individuals

Veillonella spp. are predominant bacteria found in all oral biofilms. In this study, a metatranscriptomic approach was used to investigate the gene expression levels of three oral Veillonella spp. (V. parvula, V. dispar and V. atypica) in whole stimulated saliva from caries-free volunteers and in carious lesions (n = 11 for each group). In the lesions the greatest proportion of reads were assigned to V. parvula and genes with the highest level of expression in carious samples were those coding for membrane transport systems. All three Veillonella spp. increased expression of genes involved in the catabolism of lactate and succinate, notably the alpha- and beta-subunits of L(+)-tartrate dehydratase (EC 4.2.1.32). There was also significantly increased expression of histidine biosynthesis pathway in V. parvula, suggesting higher intra-cellular levels of histidine that could provide intra-cellular buffering capacity and, therefore, assist survival in the acidic environment. Various other systems such as potassium uptake systems were also up regulated that may aid in the survival and proliferation of V. parvula in carious lesions.

Effect of Homemade Dental Powder on Population of Streptococcus Mutans In vitro

Background: Dental caries is a very common disease, and this study was conductedto identify the optimum concentration of a homemade dental powder that could be used to prevent dental caries. The formulation for this dental powder was inspired from an ancient Indian powder which is still being used in remote areas where modern dentifrices are not available. The dental powder is homemade, with its four main constituents being alum, turmeric, cloves and salt all ground into a fine powder . Objective: The aim of the study was to study the effect of a homemade dental powder on a population of Streptococcus mutans. Study design: This was arandomized controlled laboratory study. Setting: The study was carried out in the histopathology laboratory, School of Dental Sciences, University of Nairobi. Materials and methods: Streptococcus mutans were cultured and the disc diffusion technique employed, where the discs had various concentrations of the dental powder, alum, turmeric, cloves and salt, which was made by titrating with distilled water so as to form a spectrum of concentrations. The diameters of the clear zones on the agar plates were then measured to assess the effect of the dental powder on the bacterial population. Results: At a concentration of 5 g/100 ml, the alum and salt showed clear zones of 5 mm which is equivalent to that of the negative control. The clear zone of the dental powder, turmeric and cloves was greater than that of distilled water, but less than that of the 2% chlorhexidine (14.6 mm). At 7.5 g/100 ml and 10 g/100 ml, salt still had a clear zone of 5 mm, and the rest of the ingredients had clear zones of greater than 5 mm, but less than 14.6 mm. At 12.5 g/100 ml, all ingredients had clear zones of greater than 5mm, and those of the dental powder and cloves were greater than 14.6 mm, while at 15 g/100 ml, in addition to cloves and powder, salt also had a clear zone of greater than 14.6 mm. Conclusion: The dental powder, alum, turmeric, cloves and salt all showed antimicrobial activity against Streptococcus mutans. The dental powder showed highest activity, followed by cloves, salt, alum and turmeric.

Occurence of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans in subgingival plaque among patients with periodontal disease at the University of Nairobi Dental Hospital

Background: Cancer of cervix is the third leading gynaecological malignancy in the world and the leading cause of deaths in sub-Saharan Africa. Cancer of cervix can completely be treated with early diagnosis. Approaches to reduce related morbidity and mortality include screening for cervical cancer and administration of Human Papilloma Virus (HPV) vaccine to HPV non-infected females to trigger host resistance. The uptake of HPV vaccine globally has been reported to be less than 1%. Objectives: To assess the level and identify determinants of awareness of HPV vaccines among the participants Design: Cross sectional descriptive study. Setting: Umoja Estate in Embakasi, Nairobi County, Kenya. Subjects: Three hundred and eighty four (384) eligible respondents were randomly recruited into the study. Results: Most of the respondents (72%) were aged between 18 and 31 years and 42% had attained tertiary education. Fivety six point eight percent were married and 33.1% were unemployed. More than one third (38%) had monthly income of less than 20,000 Ksh (US

Nutritional and Oral Health status of an Elderly Population in Nairobi

220). Majority (60.2%) had no medical insurance cover. Only 2.3% had had HPV vaccine despite a higher awareness level of 25.8%. There was strong association between awareness about HPV vaccine and age (P=0.000); having children (p= 0.010); level of education (p=0.000); marital status (p= 0.054); having insurance (p=0.000); occupation (p=0.000) and monthly income (p=0.000). Conclusion: There was low awareness of HPV among the study population. No sensitisation programme existed in the area of study.We present a middle aged lady positive HIV who developed liver disease one year after initiation of anti-retroviral therapy (ART). Laboratory and histo pathology finding supported a diagnosis of autoimmune hepatitis (AIH). She responded well to immuno-suppressive therapy and is currently doing well on maintenance therapy for AIH and the initial ART regimen.