Interleukin‐8 and CXCL10 expression in oral keratinocytes and fibroblasts via Toll‐like receptors

Oral keratinocytes and fibroblasts may be the first line of host defense against oral microorganisms. Here, the contention that oral keratinocytes and fibroblasts recognize microbial components via Toll‐like receptors (TLRs) and participate in development of oral inflammation was examined. It was found that immortalized oral keratinocytes (RT7), fibroblasts (GT1) and primary cells express mRNA of TLRs 1–10. Interleukin‐8 (IL‐8) production by RT7 cells was induced by treatment with TLRs 1–9 with the exception of TLR7 agonist, whereas GT1 cells were induced to produce IL‐8 by all TLR agonists tested except for TLR7 and TLR9. GT1 cells showed increased CXCL10 production following treatment with agonists for TLR1/2, TLR3, TLR4, and TLR5, whereas only those for TLR3 and TLR5 increased CXCL10 production in RT7 cells. Moreover, TLR agonists differentially regulated tumor necrosis factor‐alpha‐induced IL‐8 and CXCL10 production by the tested cell types. These findings suggest that recognition of pathogenic microorganisms in oral keratinocytes and fibroblasts by TLRs may have important roles in orchestrating host immune responses via production of various chemokines.     

Oral health‐related quality of life in patients receiving home‐care nursing: associations with aspects of dental status and xerostomia

doi:10.1111/j.1741‐2358.2009.00344.x
Oral health‐related quality of life in patients receiving home‐care nursing: associations with aspects of dental status and xerostomia Objective: To explore the differences in oral status, dental attendance and dry mouth problems between patients with long‐term disease with high and low scores on Oral Health Impact Profile 14 (OHIP 14) and how patients cope with oral problems such as xerostomia and a reduced ability to brush their teeth. Background: There has been a lack of studies of oral health and oral health‐related quality of life in the frail elderly within the community services. Materials and methods: A cross‐sectional questionnaire study was conducted with 137 patients receiving home‐care nursing. Structured interviews were conducted by student nurses using OHIP‐14, items from the Xerostomia Inventory and questions concerning dental visit habits, brushing of teeth and data from medical records. Results: Eighty‐three per cent of patients had natural teeth and 60% had only natural teeth. ‘Natural teeth only’ indicated a low score on OHIP‐14. Problems with brushing and items concerning xerostomia indicated a high score on OHIP‐14. Contrasts in the assessments concerning brushing of teeth and xerostomia indicated low priority from the patients themselves and the nursing staff. Conclusion: Community health services should focus upon oral health. Both patients and nurses should assess the need for regular brushing of teeth carried out by home‐care nurses. Assessment and treatment of dry mouth problems should have higher priority.     

Plant‐based oral vaccines against zoonotic and non‐zoonotic diseases

The shared diseases between animals and humans are known as zoonotic diseases and spread infectious diseases among humans. Zoonotic diseases are not only a major burden to livestock industry but also threaten humans accounting for >60% cases of human illness. About 75% of emerging infectious diseases in humans have been reported to originate from zoonotic pathogens. Because antibiotics are frequently used to protect livestock from bacterial diseases, the development of antibiotic‐resistant strains of epidemic and zoonotic pathogens is now a major concern. Live attenuated and killed vaccines are the only option to control these infectious diseases and this approach has been used since 1890. However, major problems with this approach include high cost and injectable vaccines is impractical for >20 billion poultry animals or fish in aquaculture. Plants offer an attractive and affordable platform for vaccines against animal diseases because of their low cost, and they are free of attenuated pathogens and cold chain requirement. Therefore, several plant‐based vaccines against human and animals diseases have been developed recently that undergo clinical and regulatory approval. Plant‐based vaccines serve as ideal booster vaccines that could eliminate multiple boosters of attenuated bacteria or viruses, but requirement of injectable priming with adjuvant is a current limitation. So, new approaches like oral vaccines are needed to overcome this challenge. In this review, we discuss the progress made in plant‐based vaccines against zoonotic or other animal diseases and future challenges in advancing this field.     

Nitrogenous compounds stimulate glucose‐derived acid production by oral Streptococcus and Actinomyces

Both Streptococcus and Actinomyces can produce acids from dietary sugars and are frequently found in caries lesions. In the oral cavity, nitrogenous compounds, such as peptides and amino acids, are provided continuously by saliva and crevicular gingival fluid. Given that these bacteria can also utilize nitrogen compounds for their growth, it was hypothesized that nitrogenous compounds may influence their acid production; however, no previous studies have examined this topic. Therefore, the present study aimed to assess the effects of nitrogenous compounds (tryptone and glutamate) on glucose‐derived acid production by Streptococcus and Actinomyces. Acid production was evaluated using a pH‐stat method under anaerobic conditions, whereas the amounts of metabolic end‐products were quantified using high performance liquid chromatography. Tryptone enhanced glucose‐derived acid production by up to 2.68‐fold, whereas glutamate enhanced Streptococcus species only. However, neither tryptone nor glutamate altered the end‐product profiles, indicating that the nitrogenous compounds stimulate the whole metabolic pathways involving in acid production from glucose, but are not actively metabolized, nor do they alter metabolic pathways. These results suggest that nitrogenous compounds in the oral cavity promote acid production by Streptococcus and Actinomyces in vivo.     

MicroRNA‐1258, regulated by c‐Myb,inhibits growth and epithelial‐to‐mesenchymal transition phenotype via targeting SP1 in oral squamous cell carcinoma

The biological function and underlying mechanism of miR‐1258 has seldom been investigated in cancer progression, including in oral squamous cell carcinoma (OSCC). In the current study, we revealed that the expression level of miR‐1258 was significantly down‐regulated in OSCC tissues and cell lines. Restoration of miR‐1258 decreased OSCC cell growth and invasion. The luciferase and Western blot assays revealed that SP1 protein was a downstream target of miR‐1258. Overexpression of SP1 dismissed miR‐1258’s effect on cell growth and invasion. We also revealed that c‐Myb inhibited miR‐1258 by directly binding at its promoter. In addition, miR‐1258 inhibited PI3K/AKT and ERK signalling pathway activity. Taken together, these findings demonstrated that miR‐1258 may function as a tumour‐suppressive micorRNA in OSCC and suggested that miR‐1258 may be a potential therapeutic target for OSCC patients.     

Computational Oral Absorption Simulation for Low‐Solubility Compounds

Bile micelles play an important role in oral absorption of low‐solubility compounds. Bile micelles can affect solubility, dissolution rate, and permeability. For the pH–solubility profile in bile micelles, the Henderson–Hasselbalch equation should be modified to take bile‐micelle partition into account. For the dissolution rate, in the Nernst–Brunner equation, the effective diffusion coefficient in bile‐micelle media should be used instead of the monomer diffusion coefficient. The diffusion coefficient of bile micelles is 8‐ to 18‐fold smaller than that of monomer molecules. For permeability, the effective diffusion coefficient in the unstirred water layer adjacent to the epithelial membrane, and the free fraction at the epithelial membrane surface should be taken into account. The importance of these aspects is demonstrated here using several in vivo and clinical oral‐absorption data of low‐solubility model compounds. Using the theoretical equations, the food effect on oral absorption is further discussed.     

Assessing changes in oral health‐related quality of life and its factors in community‐dwelling older Brazilians

doi: 10.1111/j.1741‐2358.2012.00656.x Assessing changes in oral health‐related quality of life and its factors in community‐dwelling older Brazilians Objective: To describe changes in oral health‐related quality of life and to evaluate the associations of these changes in community‐dwelling older people. Materials and methods: In this longitudinal study a representative sample of 872 older people, living in Brazil, was evaluated during 2004. The follow‐up was carried out during 2008, with 587 older persons evaluated. A questionnaire assessing socio‐demographic information, health history, oral health‐impact profile and number of natural teeth was used. Changes in oral health‐related quality of life were categorized as improvement or deterioration. Data analysis was performed using a hierarchical approach based in a conceptual framework. A hierarchal approach was carried out using Poisson regressions. Results: Older persons living in rural areas, those who reported brushing once a day or less and older persons with fewer natural teeth had an increased chance of reporting deterioration in oral health‐related quality of life. Women and participants who received a minimum wage of less than US$219.50 were more likely to report improvement in oral health‐related quality of life. Conclusion: The results of this study suggest that changes in the oral health‐related quality of life are influenced by many of the variables that were included in the conceptual framework.     

A five‐step risk management process for geriatric dental practice during SARS‐CoV‐2 pandemic

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is an RNA virus that causes coronavirus infection (COVID‐19). COVID‐19 is a highly contagious disease transmitted through respiratory droplets, saliva and other contact routes. Within 10 months of its outbreak, SARS‐CoV‐2 has infected more than 23 million people around the world. Evidence suggests that older adults are the most vulnerable to infection and have an increased risk of mortality. Reduced immunity and underlying medical conditions make them risk‐prone and vulnerable to critical care. Older adults affected with the SARS‐CoV‐2 virus present with distinct clinical manifestations necessitating specific treatment needs and management protocols. While it is crucial to prevent the spread of novel coronavirus (2019‐nCoV), the role of oral healthcare workers in addressing the specific needs of ageing adult patients by adopting specific guidelines and appropriate infection control protocols is timely. This paper aims to develop specific guidelines and protocols for the dental management of geriatric patients during the COVID‐19 pandemic.     

Prevalence and antifungal drug sensitivity of non‐albicans Candida in oral rinse samples of self‐caring elderly

doi: 10.1111/j.1741‐2358.2010.00407.x
Prevalence and antifungal drug sensitivity of non‐albicans Candida in oral rinse samples of self‐caring elderly Aim: To assess the prevalence and antifungal drug sensitivity of non‐albicans Candida (NAC) species in elderly outpatients. Materials and methods: We investigated oral rinse samples of 194 self‐caring elderly population (mean age 83 years) with emphasis on background factors for harbouring NAC. Susceptibility of Candida species to antifungal drugs was determined using standard methodology. Multiple logistic regression analysis was performed taking positive NAC count as the dependent variable and a number of known Candida risk factors as independent variables. Results: Prevalence of candidal carriage of the population was 78.4%, of which 0.5% of the subjects were NAC positive. Candida dubliniensis was the most prevalent NAC species, followed by Candida glabrata and Candida parapsilosis. The NAC positive elderly were more often edentulous with dental prostheses or had fewer teeth than Candida albicans‐positive or yeast‐negative subjects. Dental caries slightly increased the risk for having NAC strains (odds ratio 1.08), whilst greater age appeared to lower the risk (odds ratio 0.77). Candida species were susceptible to the commonly used antifungal agents in general, but with considerable variation among species. Occasionally, some NAC exhibited lower antifungal susceptibility. Conclusion: The possibility of oral reservoirs of NAC strains which are resistant to common antifungals should be noted in elderly outpatients.