Category: News

The 2023 International Association for Dental Research (IADR) conference in Bogota, Colombia was an exciting event for the DeRouen Center. We had the honor of having five abstracts accepted for presentation at the conference, highlighting our research conducted by our dedicated international team. These abstracts represented a significant achievement for the DeRouen Center and demonstrated our continued success in advancing oral health on a global scale.

During the conference, the accepted abstracts from the DeRouen Center took center stage as interactive talks presented by Ana Lucia Seminario (University of Washington) entitled “Integrating oral health within Kenyan HIV research/policy structure: Stakeholder analysis”, Arthur Kemoli (University of Nairobi) entitled “Oral health status among visually impaired adolescents in Kenya”, Eraldo Pesaressi (Universidad Peruana Cayetano Heredia) entitled “Oral health perceptions in MSM alcohol consumers with HIV”, Johanna Belen Juarez (Universidad Peruana Cayetano Heredia) entitled “Dental utilization of refugee children is associated with area of resettlement”, and Sara Stanley (University of Washington) entitled “Implementing an app for data collection in a Peruvian HIV-clinic”. The presentations highlighted the research findings and innovative approaches to addressing oral health challenges in both Peru, Kenya, and the United States. The talks sparked engaging discussions, fostering collaboration, and knowledge sharing among fellow researchers and dental professionals in attendance.

The DeRouen Center’s presence at the conference demonstrates our continued commitment to international collaborations, knowledge exchange, and the pursuit of excellence in oral health research. We look forward to attending the next IADR conference in New Orleans, USA in 2024.

The kickoff of the UW DeRouen Center’s NIH R21 grant entitled “Dynamics of HIV-infection, Oral Innate Immunity and The Development of Oral Diseases in Children” took place in Kisumu, Kenya in February 2023.

The event brought together researchers and healthcare professionals to launch the grant’s research activities. Among the key individuals present were Dr. Ana Lucia Seminario (principal investigator, and Co-PI with Dr. Whasun Chung), Dr. Arthur Kemoli, (Kenyan site director), Dr. Immaculate Opondo (study coordinator), Maureen Aluoch (research assistant) Mercyline Muhonja (research assistant), and Dr. Caitlin Fehlinger, (pediatric dental resident). Our dedicated team spent four days testing and initiating the grant at Jaramogi Oginga Odinga Teaching and Referral Hospital in Kisumu.

Oral diseases are among the most prevalent non-communicable diseases worldwide. Despite significant successes in the treatment for HIV, children with HIV continue to experience more oral diseases compared to uninfected children. This exploratory study assesses the extent to which HIV infection influences the occurrence and progression of oral diseases among HIV/AIDS Kenyan children and to create research capacity in global oral health.

The kickoff event in Kisumu was an exciting milestone for the DeRouen Center, marking the beginnings of oral health HIV research in western Kenya.

Dr. Waranuch Pitiphat, former Dean of the School of Dentistry at Khon Kaen University, is a renowned Thai researcher who has made significant contributions to the field of oral health, with her work receiving recognition and support from the United States’ National Institutes of Health (NIH). As highlighted on the Fogarty International Center’s website at the NIH, Dr. Pitiphat’ s research endeavors in Thailand have focused on cultivating oral health research and addressing the disparities prevalent in the oral health domain.

One notable achievement in Dr. Pitiphat’ s career is her success in obtaining NIH grants, specifically the D71 and D43 training grants for southeast Asia. These grants awarded have enabled her to establish a research training program that integrates oral health research into the curriculum of Thai dental schools. By equipping dental students with research skills and fostering a research-oriented mindset, Dr. Pitiphat aims to enhance their capabilities and contribute to advancements in oral health research. She has organized workshops, seminars, and collaborative projects that bring together oral health professionals from Thailand and other international partners. These initiatives not only facilitate the sharing of research findings and best practices but also foster interdisciplinary collaborations, strengthening the oral health research community within Thailand.

Dr. Pitiphat’ s achievements with D71 and D43 awards highlight her dedication to advancing oral health research and capacity-building efforts in Thailand. By empowering future dental professionals with research skills and promoting collaboration among researchers, she has significantly contributed to improving oral health outcomes and strengthening the research landscape throughout southeast Asia.

In February 2023, as part of the National Institutes of Health (NIH) grant named “TABASAMU” awarded to the University of Washington (UW) and University of Nairobi (UoN), a team of researchers and professionals embarked on an international trip to Kenya. The purpose of the trip was to conduct focus groups and meet with potential oral health research trainees in four cities: Kisumu, Eldoret, Nairobi, and Mombasa. The trip involved a team of six travelers including Dr. Ana Lucia Seminario (UW), Dr. Frank Roberts (UW), Dr. Jenipher Ober-Oluoch (University of Rwanda), Dr. Arthur Kemoli (UoN), Dr. Immaculate Opondo (Maseno University), and Sara Stanley (UW). The TABASAMU project (Grant # 1D71TW011823-01) is the precursor planning grant that prepares the path for a future interdisciplinary research training program in Kenya.

Led by Dr. Jenipher Ober-Oluoch and Sara Stanley, the team conducted a series of focus groups to gather data on oral health research capacity in Kenya, with the opportunity to meet with potential oral health research trainees in each of the four cities. These meetings allowed the team to identify promising individuals for future trainee and research opportunities.

In addition to the focus groups, the team attended the Kenya Medical Research Institute’s (KEMRI) Annual Scientific and Health (KASH) Conference in Nairobi. Dr. Frank Roberts was a speaker at the conference and gave a lecture on periodontal disease and HIV. Attending the conference allowed the team to connect with other researchers and professionals and learn about the latest developments in oral health research.

This second TABASAMU trip to Kenya was another productive and enriching experience for the team and has laid the groundwork for a future NIH training grant to enhance oral health research capacity in Kenya, and future collaborations between University of Washington, University of Nairobi, and other partners within the country.

This past February, Dr. Frank Roberts from University of Washington’s (UW) School of Dentistry, was invited to give a talk at the 2023 KEMRI Annual Scientific and Health (KASH) conference. The KASH conference is an annual event organized by the Kenya Medical Research Institute (KEMRI). KEMRI is a leading medical research organization in Africa that conducts research on various health issues, including infectious diseases, non-communicable diseases, health systems research, and public health. The conference brings together scientists, researchers, policymakers, and other stakeholders from the health sector to discuss and share the latest research findings, innovations, and best practices in health research.

Dr. Robert’s presentation topic was focused on the interaction between HIV and periodontal diseases. Periodontal disease (gum disease) is an inflammatory condition that affects the tissues and bone that support the teeth. It is caused by a bacterial infection and can lead to tooth loss if left untreated. HIV infection can increase the risk of developing periodontal disease and can also make the disease more severe. Research has shown that people with HIV are more likely to have periodontal disease than those without HIV. This may be due to the fact that HIV weakens the immune system, making it harder for the body to fight off the bacterial infection that causes periodontal disease. In addition, some antiretroviral medications used to treat HIV can cause dry mouth, which can increase the risk of developing other oral health problems including caries (cavities). Periodontal disease can also have an impact on HIV disease progression, with studies suggesting that periodontal disease may lead to increased HIV viral load and decreased T-cell counts, which are key indicators of HIV disease progression.  Fortunately, current treatment strategies to control HIV infection (HAART, etc.) also reduce the ravages of HIV-periodontitis.  Dr. Roberts lectured to physicians, nurses, and other Kenyan healthcare workers on the importance of oral health examinations and interventions to improve general health.

Dr. Roberts is the Associate Dean for Regional Affairs, Acting Chair of the Department of Periodontics, and is the Program Director for the Regional Initiatives in Dental Education (RIDE) program at the University of Washington.  He also serves as the Staff Periodontist for the Seattle Veterans Administration Dental Clinic. He accompanied the University of Washington and University of Nairobi’s TABASAMU research group to Kenya to meet with key project stakeholders, assist with trainee focus groups, and attend the KASH conference.

In February 2023, as part of the National Institutes of Health (NIH) D71 TABASAMU grant (1D71TW011823-01) awarded to the University of Washington and University of Nairobi, a series of focus groups were conducted in Kenya to explore the potential trainees’ knowledge, attitudes, perceptions, and barriers of oral health research capacity within the country. The focus groups took place in four cities including Kisumu, Eldoret, Nairobi, and Mombasa.

Dr. Jenipher Ober-Oluoch facilitated the groups and used the nominal focus group technique to explore potential future trainees’ perceptions of oral health research capacity. The nominal group technique involved the identification of two key themes or concepts related to oral health research capacity, which were then used to guide the discussion among participants. This technique has advantages over traditional focus groups such as including everyone in the exercise, and it reduces the possibility of conflict within groups.

Overall, the focus groups provided valuable insights into the oral health providers’ beliefs and attitudes towards oral health research capacity in Kenya. The data collected will be used to inform the development of a D43 NIH training grant aimed at increasing opportunities for trainees to engage in research training and projects within Kenya.

The Universidad Continental in Huancayo, Peru, recently hosted a research methodology workshop on oral health, which offered courses in various topics related to dental research. The workshop aimed to equip participants with the necessary skills and knowledge to conduct high-quality research in oral health. The courses covered a range of topics, including epidemiological methods, grant preparation, evidence-based dentistry, ethics, biostatistics, and study design. The workshop was an excellent opportunity for dental professionals and researchers to enhance their research skills and knowledge.

The Universidad Continental is a leading higher education institution in Peru that offers a range of undergraduate and graduate programs. The university is committed to providing high-quality education and research opportunities to its students and the wider community. The research methodology workshop on oral health is an example of the university’s commitment to promoting research excellence in dental health. The workshop was led by experienced dental researchers and educators who provided participants with expert guidance on various aspects of dental research including Dr. Ana Lucia Seminario (University of Washington), Francisco Ramos-Gomez (University of California Los Angeles), and Joanna Scott (University of Missouri).

Overall, the research methodology workshop on oral health held at the Universidad Continental in Huancayo, Peru, was a highly informative and beneficial event for dental professionals and researchers. The workshop covered a range of important topics related to dental research and provided participants with the necessary skills and knowledge to conduct high-quality research in oral health. The Universidad Continental’s commitment to promoting research excellence in dental health is evident through events like this, and it is hoped that similar workshops will continue to be held in the future to advance dental research in Peru and beyond.

A DeRouen Center collaborator, Dr. Yan Wang, is taking part in the Center’s Children’s Healthy Oral Management Project (CHOMP) grant in Kenya. Dr. Wang is studying the oral microbiome of Kenyan children and adolescents who are living with HIV and taking antiretroviral therapy (ART). The collected samples were sent to Dr. Aldrovandi’s Microbiology Lab at University of California Los Angeles for analysis. The aims of the CHOMP study are to measure the association between oral and systemic inflammation in the Kenya Pediatric Studies (KPS) cohort, and to assess the impact of oral diseases and inflammation on children’s quality of life. The secondary aim is to assess acceptability and feasibility of integrating routine oral health care in the setting of routine Pediatric HIV care.

Dr. Wang is an Adjunct Assistant Professor in the Public and Population Health department at the UCLA School of Dentistry. She received her PhD in Biostatistics at Fielding School of Public Health, UCLA, and subsequently completed both a one-year NIH T37 postdoc and a two-year T32 postdoc.

The CHOMP study has furthered the study of HIV in children and adolescents, and has yielded two published manuscripts – “Oral Diseases and Oral Health–Related Quality of Life among Kenyan

Children and Adolescents with HIV”, and “The effect of antiretroviral therapy initiation on vitamin D levels and four oral diseases among Kenyan children and adolescents living with HIV”. We are happy to have Dr. Wang working with us and look forward to her continued collaboration in furthering oral health research.

Oral diseases are among the most prevalent non-communicable diseases (NCDs) worldwide. Salivary antimicrobial peptides (AMPs) are proteins regulated by our immune system that disrupt the membrane integrity of bacteria. There is very limited data on AMPs in young children living with HIV. In Kenya, where about 5% of the population is HIV positive, there are an estimated 105,000 infected children and adolescents aged 0-14. A newly awarded National Institute of Health (NIH) grant entitled “Dynamics of HIV-infection, Oral Innate Immunity and The Development of Oral Diseases in Children” aims to assess the extent to which HIV infection influences the occurrence and progression of oral diseases among HIV/AIDS Kenyan children and to create research capacity in global oral health by expanding current lab infrastructure to allow local analysis of salivary AMPs in the context of HIV. This University of Washington (UW) and University of Nairobi (UoN) award is led by Drs. Ana Lucia Seminario and Whasun Chung at UW, and Arthur Kemoli at UoN.

This longitudinal study will be conducted in a cohort of children who receive care at Jaramogi Oginga Odinga Teaching & Referral Hospital (and other affiliated HIV clinics in the Kisumu area), the largest local teaching and referral hospital in western Kenya. Over 12 months, we will recruit and follow a cohort of approximately 300 children (3-4 years old) stratified by presence of HIV. We will assess participants for anti-retroviral therapy (ART) adherence, length and regimen; dental plaque; CD4; HIV-1 RNA; and additional medications. Our aims are to: 1) Describe the impact of HIV infection on the secretion of salivary antimicrobial peptides at baseline and over a 12-month follow-up period. 2) Determine the associations between salivary AMPs and oral diseases in the context of HIV. 3) Enhance existing HIV research capacity. We will expand current human and infrastructure resources to include oral health research. While currently the study of salivary AMPs is conducted out of Kenya, we will build upon existing lab assets allowing locals to conduct these analyses, thus starting a line of research that increases Kenyan research opportunities.

In February 2023, researchers traveled to Kisumu, Kenya to kick-off the grant and begin enrollment.

The taste buds in our tongues contain receptor cells that detect food particles dissolved in saliva.  G-protein coupled receptors on the surface of those receptor cells have been identified that respond to sweet, savory, or bitter tasting chemicals.  Twenty-five different G-protein coupled bitter taste receptors have been identified in humans.  When these bitter receptors are activated on the tongue, we sense a bitter taste that promotes rejection of the food we are eating.  It turns out that bitter taste receptors are not just in the taste buds of the tongue, however.  Bitter taste receptors are also found in the epithelium of the nasal cavity, trachea, gut, urethra and other tissues.  The bitter taste receptors in tissues outside the taste buds do not play a role in taste perception.  Instead, these receptors detect chemicals released by pathogens.  Activation of the bitter receptors in these other tissues trigger host-defense and immune responses that help protect against disease.

At the University of Washington, we identified one type of bitter taste receptor (T2R38) in gingival epithelial cells of the gums.  There are three important single nucleotide polymorphisms (genetic differences) in the TAS2R38 bitter taste receptor gene, which codes for the T2R38 receptor.  These polymorphisms result in two common genetic haplotypes, which are labeled PAV (Proline, Alanine, Valine) and AVI (Alanine, Valine, Isoleucine) based on the amino acid substitutions that result at positions 49, 262, and 296 of the receptor.  People inherit two haplotypes, one from their father and the other from their mother, resulting in a genetic diplotype.  People who have PAV/PAV or PAV/AVI genetic diplotypes perceive thiourea-containing compounds as bitter tasting, whereas those with the AVI/AVI genotype find these compounds to be almost taste-less.  In our work at University of Washington, we found that gingival epithelial cells with PAV/PAV and AVI/AVI diplotypes responded differently to the bacteria involved in dental caries and periodontal disease.  Gingival epithelial cells with PAV/PAV genotype responded more to S. mutans (a pathogen involved in caries), whereas gingival epithelial cells with the AVI/AVI genotype responded more to P. gingivalis (a pathogen involved in periodontal disease).

Previous studies have shown a protective effect against caries for those with the PAV haplotype of TAS2R38.  The previous laboratory work at University of Washington led us to believe that the AVI haplotype might be protective against periodontal disease.  We conducted a cross-sectional study at Khon Kaen University in Thailand to learn more about genetic differences in the T2R38 bitter taste receptor among Thai people.  We also examined the association of genetic differences with measures of caries (decayed-missing-filled teeth) and periodontal disease (defined as one site with probing depth greater than 5 mm).  In the study, we genotyped 250 patients seeking care at Khon Kaen University Dental Hospital.  Of those patients, 46% were PAV/PAV genotype, 42% were PAV/AVI, and 12% were AVI/AVI.  These distributions are similar to that seen in other studies of Asian populations.  As we expected based on the prior laboratory work at University of Washington, those patients with an AVI haplotype had less periodontal disease than those with the PAV/PAV genotype.  However, trends for differences in decayed-missing-filled teeth did not reach statistical significance in our study.  This study provides evidence of the importance of the T2R38 bitter taste receptor in maintaining oral health.