Breakdown of Symbiosis in Radiation-Induced Oral Mucositis

Microbial Analysis of Obturators During Maxillofacial Prosthodontic Treatment Over an 8-Year Period

The aim of the study was to investigate the microbial colonization (by Candida species, anaerobic and facultative anaerobic bacteria) of maxillary obturators used for the restoration of maxillary defects, including during radiotherapy.

Retrospective cohort study.

Fifteen patients requiring a maxillary obturator prosthesis had swabs of their obturators and adjacent tissues taken at different stages of their treatment over a period of 8 years.

Identification of microbial species from the swabs was carried out using randomly amplified polymorphic DNA polymerase chain reaction (RAPD PCR) analysis, checkerboard DNA-DNA hybridization, CHROMagar Candida chromogenic agar, and DNA sequencing.

Candida species were detected in all patients and all patients developed mucositis and candidiasis during radiotherapy which was associated with an increase in colonization of surfaces with Candida spp., particularly C albicans. Microbial colonization increased during radiotherapy and as an obturator aged, and decreased following a reline, delivery of a new prosthesis, or antifungal treatment during radiotherapy.

Microbial colonization of maxillary obturators was related to the stage of treatment, age of the obturator material, radiotherapy and antifungal medications, and antifungal treatment may be recommended if C albicans colonization of palatal tissues is greater than 105 colony-forming units per cm2 following the first week of radiotherapy.

Omega-3 nanoemulgel in prevention of radiation-induced oral mucositis and its associated effect on microbiome: a randomized clinical trial

BACKGROUND

Oral mucositis (OM) is recognized as one of the most frequent debilitating sequelae encountered by head and neck cancer (HNC) patients treated by radiotherapy. This results in severe mucosal tissue inflammation and oral ulcerations that interfere with patient's nutrition, quality of life (QoL) and survival. Omega-3 (ω-3) polyunsaturated fatty acids (PUFAs) have recently gained special interest in dealing with oral diseases owing to its anti-inflammatory, anti-oxidant and wound healing properties. Thus, this study aims to assess topical Omega-3 nanoemulgel efficacy in prevention of radiation-induced oral mucositis and regulation of oral microbial dysbiosis.

MATERIALS AND METHODS

Thirty-four head and neck cancer patients planned to receive radiotherapy were randomly allocated into two groups: Group I: conventional preventive treatment and Group II: topical Omega-3 nanoemulgel. Patients were evaluated at baseline, three and six weeks after treatment using the World Health Organization (WHO) grading system for oral mucositis severity, Visual Analogue Scale (VAS) for perceived pain severity, and MD-Anderson Symptom Inventory for Head and Neck cancer (MDASI-HN) for QoL. Oral swabs were collected to assess oral microbiome changes.

RESULTS

VAS scores and WHO mucositis grades were significantly lower after six weeks of treatment with topical Omega-3 nanoemulgel when compared to the conventional treatment. The total MDASI score was significantly higher in the control group after three weeks of treatment, and the head and neck subscale differed significantly at both three and six weeks. A significant reduction in Firmicutes/Bacteroidetes ratio was observed after six weeks in the test group indicating less microbial dysbiosis.

CONCLUSIONS

Topical Omega-3 nanoemulgel demonstrated a beneficial effect in prevention of radiation-induced oral mucositis with a possibility of regulating oral microbial dysbiosis.

Symptom clusters after chemoradiotherapy in discharged nasopharyngeal carcinoma patients

Objective

To investigate the incidence of complications and types of chemoradiotherepy induces symptom clusters in patients with nasopharyngeal carcinoma (NPC) who were first diagnosed after treatment and discharged from hospital.

Methods

After their discharge home, 130 NPC patients who had been treated with chemoradiotherapy were asked to complete a modified Chinese version of the Quality of Life Questionnaire-Head and Neck Module developed by the European Organization for the Research and Treatment of Cancer in the Head and Neck. Symptom clusters in patients were identified through exploratory factor analysis.

Results

The most serious symptoms for discharged NPC patients who had received chemoradiotherapy were dental problems, a sense of obstruction while swallowing, embarrassment in physical contact with family members and friends, difficulty in speaking with others, and embarrassment in public. The six symptom clusters identified through exploratory factor analysis were (1) painful eating, (2) social difficulties, (3) psychological disorders, (4) symptomatic shame, (5) teeth/throat injuries, and (6) sensory abnormalities. The total contribution rate of variance was 65.73%.

Conclusion

NPC patients who are treated with chemoradiotherapy can experience adverse symptom clusters that continue after discharge. Nurses should evaluate the patients' symptoms before discharge and provide targeted health education services which would reduce the patients' complications and improve the quality of life at home. Besides, medical staff should evaluate the complications in a timely and comprehensive manner and provide individualized health education for the affected patients to help them manage chemoradiotherapy side effects.

Effectiveness of natural-based products for radiation-induced oral mucositis therapy: A systematic review

Radiation-induced oral mucositis (RIOM) is one of the common toxic reactions from ionizing radiation and normal tissue injuries as a complication of radiation therapy and chemotherapy. Radiation therapy is an option for the treatment of head and neck cancer (HNC). The use of natural products is an alternative therapy for RIOM. This review aimed to describe the effectiveness of natural-based products (NBPs) in reducing the severity, pain score, incidence, oral lesion size, and other symptoms such as dysphagia, dysarthria, and odynophagia. This systematic review follows the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. Pubmed, ScienceDirect, and Ebscohost-CINAHL Plus databases were used for article searches. The inclusion criteria were studies published from 2012 to 2022 with full text available, in English, a study in humans, and a Randomized Clinical Trial (RCT) that evaluate the effect of NBPs therapy in RIOM patients diagnosed with HNC. This study's population was HNC patients who had oral mucositis after receiving radiation or chemical therapy. The NBPs were manuka honey, thyme honey, aloe vera, calendula, zataria multiflora, Plantago major L., and turmeric. Eight of the twelve included articles showed significant effectiveness against RIOM in various parameters, such as a decrease in severity, incidence rate, pain score, oral lesion size, and the other symptoms of oral mucositis such as dysphagia and burning mouth syndrome. This review concludes that NBPs therapy is effective for RIOM in HNC patients.

Ascidian-Inspired Temperature-Switchable Hydrogels with Antioxidant Fullerenols for Protecting Radiation-Induced Oral Mucositis and Maintaining the Homeostasis of Oral Microbiota

A key characteristic of radiation-induced oral mucositis (RIOM) is oxidative stress mediated by the "reactive oxygen species (ROS) storm" generated from water radiolysis, resulting in severe pathological lesions, accompanied by a disturbance of oral microbiota. Therefore, a sprayable in situ hydrogel loaded with "free radical sponge" fullerenols (FOH) is developed as antioxidant agent for RIOM radioprotection. Inspired by marine organisms, 3,4,5-trihydroxyphenylalanine (TOPA) which is enriched in ascidians is grafted to clinically approved temperature-switchable Pluronic F127 to produce gallic acid (containing the TOPA fragment)-modified Pluronic F127 (MGA) hydrogels to resist the fast loss of FOH via biomimetic adhesion during oral movement and saliva erosion. Based on this, progressive RIOM found in mice is alleviated by treatment of FOH-loaded MGA hydrogels whether pre-irradiation prophylactic administration or post-irradiation therapeutic administration, which contributes to maintaining the homeostasis of oral microbiota. Mechanistically, FOH inhibits cell apoptosis by scavenging radiation-induced excess ROS and up-regulates the inherent enzymatic antioxidants, thereby protecting the proliferation and migration of mucosal epithelial cells. In conclusion, this work not only provides proof-of-principle evidence for the oral radioprotection of FOH by blocking the "ROS storm", but also provides an effective and easy-to-use hydrogel system for mucosal in situ administration.

Modulation of the nanoscale motion rate of Candida albicans by X-rays

Introduction

Patients undergoing cancer treatment by radiation therapy commonly develop Candida albicans infections (candidiasis). Such infections are generally treated by antifungals that unfortunately also induce numerous secondary effects in the patient. Additional to the effect on the immune system, ionizing radiation influences the vital activity of C. albicans cells themselves; however, the reaction of C. albicans to ionizing radiation acting simultaneously with antifungals is much less well documented. In this study, we explored the effects of ionizing radiation and an antifungal drug and their combined effect on C. albicans.

Methods

The study essentially relied on a novel technique, referred to as optical nanomotion detection (ONMD) that monitors the viability and metabolic activity of the yeast cells in a label and attachment-free manner.

Results and discussion

Our findings demonstrate that after exposure to X-ray radiation alone or in combination with fluconazole, low-frequency nanoscale oscillations of whole cells are suppressed and the nanomotion rate depends on the phase of the cell cycle, absorbed dose, fluconazole concentration, and post-irradiation period. In a further development, the ONMD method can help in rapidly determining the sensitivity of C. albicans to antifungals and the individual concentration of antifungals in cancer patients undergoing radiation therapy.

Effect of synbiotic mouthwash on oral mucositis induced by radiotherapy in oral cancer patients: a double-blind randomized clinical trial

PURPOSE

Considering the complex pathobiology of oral mucositis, especially in oral cancer patients, the prevention and treatment of oral mucositis in patients undergoing radiotherapy remains an essential and clinically crucial unmet need. The present study aims to investigate and compare the effects of synbiotic mouthwash with normal saline mouthwash on the prevention and control of radiotherapy-induced oral mucositis in oral cancer patients.

METHODS

Double-blind, randomized clinical trial (RCT) performed on 64 oral cancer patients who underwent radiotherapy (IRCT20201106049288N1, registration date: 2020-12-23). Patients were divided randomly into the case (32 subjects) and control (32 subjects) groups. All patients underwent intensity-modulated radiotherapy and received 6000 cGY of radiotherapy in 34 fractions. All patients received the usual treatment for mucositis, but in the case group, synbiotic mouthwash was prescribed and in the control group, normal saline mouthwash was prescribed from a day before the start to the end of radiotherapy treatment. Patients were monitored every session for 6 weeks to check the progression, oral involvement severity, and mucositis grade.

RESULTS

The case group showed a significant reduction in the oral mucositis severity. The mucositis grade in the case group from the 7th session of oral examination was significantly lower than the control (p < 0.05), and this significant difference persisted until the last session of oral examination. Incidence rates of severe oral mucositis (grade 3) during the treatment period were 11.59% in the case and 36.45% in control (p < 0.001).

CONCLUSION

Synbiotic mouthwash significantly reduces and prevents oral mucositis intensity in oral cancer patients undergoing radiotherapy.

Selecting the Best Surgical Treatment Methods in Oro-Antral Communications

INTRODUCTION

an oro-antral communication is defined as a permanent pathological connection between the maxillary sinus and the septic oral cavity. Several flaps can be used for the closure (buccal flap, palatal flap, combination techniques) but relapses occur often in case of a large defects and underlying general conditions. Bichat fad pad flap is a multipotent pedicled fatty tissue that is easily accessible from the oral cavity that can be used for the closure of medium-sized defects, even in immunocompromised patients due to its stem cell capacity.

MATERIALS AND METHODS

the medical information of the patients diagnosed with oro-antral communications who were admitted and treated in the Oral and Maxillo-Facial Clinic Targu Mures, between 2013 and 2020 were analyzed. A database containing general information, reported causes, associated diseases, surgical methods used during admission, and relapses, was created. The information was statistically processed. The written consent and ethical approval were obtained.

RESULTS

the study shows that from a total of 140 cases, 72 were treated using buccal advancement flap, 49 using Bichat fat pad flap, and 19 using palatal flaps. The dimensions of the communications ranged between 0.3 cm and 1.5 cm. Several statistically significant results could be found when comparing the surgical methods. Of the 72 patients treated with buccal advancement flaps, 25 presented relapses as opposed to the patients treated with Bichat fat pad flaps who showed no complications, p < 0.05. Analysing this aspect further, all large defects (10 cases) ranging from 0.6 cm to 1.5 cm treated with advancement buccal flaps (Rehrmann flaps) showed relapses (p < 0.05). Considering the general conditions, out of 7 patients who received radiotherapy 4 presented relapses, as opposed to the healthy patients, p < 0.05. Regarding the reintervention for the relapsed cases, the majority of the cases treated a second time with buccal advancement flap (5 out of 7 cases) failed as opposed to the Bichat fat pad flap with no further relapses (p < 0.05).

CONCLUSIONS

the most frequently used surgical treatment is the buccal flap, which also has the highest relapse rate. Both primary treatment with Bichat fat-pad flap and re-treatment of relapses using this flap have had 100% success rates, even in patients with general associated conditions, in contrast with patients treated by using the buccal flap. The dimensions of the oro-antral communication and general conditions are crucial factors for the success of the surgical treatment.

Metabolomics application for the design of an optimal diet

Precision nutrition is an emerging branch of nutrition science that aims to use modern omics technologies (genomics, proteomics, and metabolomics) to assess an individual's response to specific foods or dietary patterns and thereby determine the most effective diet or lifestyle interventions to prevent or treat specific diseases. Metabolomics is vital to nearly every aspect of precision nutrition. It can be targeted or untargeted, and it has many applications. Indeed, it can be used to comprehensively characterize the thousands of chemicals in foods, identify food by-products in human biofluids or tissues, characterize nutrient deficiencies or excesses, monitor biochemical responses to dietary interventions, track long- or short-term dietary habits, and guide the development of nutritional therapies. Indeed, metabolomics can be coupled with genomics and proteomics to study and advance the field of precision nutrition. Integrating omics with epidemiological and clinical data will begin to define the beneficial effects of human food metabolites. In this review, we present the metabolome and its relationship to precision nutrition. Moreover, we describe the different techniques used in metabolomics and present how metabolomics has been applied to advance the field of precision nutrition by providing notable examples and cases.

Molecular Mapping of Antifungal Mechanisms Accessing Biomaterials and New Agents to Target Oral Candidiasis

Oral candidiasis has a high rate of development, especially in immunocompromised patients. Immunosuppressive and cytotoxic therapies in hospitalized HIV and cancer patients are known to induce the poor management of adverse reactions, where local and systemic candidiasis become highly resistant to conventional antifungal therapy. The development of oral candidiasis is triggered by several mechanisms that determine oral epithelium imbalances, resulting in poor local defense and a delayed immune system response. As a result, pathogenic fungi colonies disseminate and form resistant biofilms, promoting serious challenges in initiating a proper therapeutic protocol. Hence, this study of the literature aimed to discuss possibilities and new trends through antifungal therapy for buccal drug administration. A large number of studies explored the antifungal activity of new agents or synergic components that may enhance the effect of classic drugs. It was of significant interest to find connections between smart biomaterials and their activity, to find molecular responses and mechanisms that can conquer the multidrug resistance of fungi strains, and to transpose them into a molecular map. Overall, attention is focused on the nanocolloids domain, nanoparticles, nanocomposite synthesis, and the design of polymeric platforms to satisfy sustained antifungal activity and high biocompatibility with the oral mucosa.

Roles of Toll-Like Receptors in Radiotherapy- and Chemotherapy-Induced Oral Mucositis: A Concise Review

Radiotherapy and/or chemotherapy-induced oral mucositis (RIOM/CIOM) is a common complication in cancer patients, leading to negative clinical manifestations, reduced quality of life, and impacting compliance with anticancer treatment. The composition and metabolic function of the oral microbiome, as well as the innate immune response of the oral mucosa are severely altered during chemotherapy or radiotherapy, promoting the expression of inflammatory mediators by direct and indirect mechanisms. Commensal oral bacteria-mediated innate immune signaling via Toll-like receptors (TLRs) ambiguously shapes radiotherapy- and/or chemotherapy-induced oral damage. To date, there has been no comprehensive overview of the role of TLRs in RIOM/CIOM. This review aims to provide a narrative of the involvement of TLRs, including TLR2, TLR4, TLR5, and TLR9, in RIOM/CIOM, mainly by mediating the interaction between the host and microorganisms. As such, we suggest that these TLR signaling pathways are a novel mechanism of RIOM/CIOM with considerable potential for use in therapeutic interventions. More studies are needed in the future to investigate the role of different TLRs in RIOM/CIOM to provide a reference for the precise control of RIOM/CIOM.

Oral-Gut Microbiome Axis in the Pathogenesis of Cancer Treatment-Induced Oral Mucositis

Oral mucositis (OM) is one of the most common and debilitating oral complications of cancer treatments including chemotherapy, radiotherapy, and hematopoietic stem cell transplantation. It is associated with severe pain and difficulties in chewing, swallowing, and speech. This leads to impairment of basic oral functions and could result in unplanned treatment interruption or modification. As such, OM negatively impacts both patients' quality of life as well as tumor prognostic outcomes. Understanding pathways underlying OM pathogenesis help identify new targets for intervention or prevention. The pathophysiology of OM has been widely studied over past decades with several pathways related to oxidative stress, inflammation, and molecular and cellular signaling being implicated. In this mini-review, we will discuss the emerging role of the oral-gut microbiome axis in the development of OM. Particularly, we will elaborate on how the alterations in the oral and gut microbiota as well as intestinal dysfunction caused by cancer treatments could contribute to the pathogenesis of OM. Further, we will briefly discuss the potential methods for targeting the oral-gut microbiome axis to improve OM outcomes.