Bifidobacterium animalis subsp lactis HN019 presents antimicrobial potential against periodontopathogens and modulates the immunological response of oral mucosa in periodontitis patients.

OBJECTIVE: To evaluate the effects of Bifidobacterium animalis subsp. lactis HN019 (HN019) on clinical periodontal parameters (plaque accumulation and gingival bleeding), on immunocompetence of gingival tissues [expression of beta-defensin (BD)-3, toll-like receptor 4 (TLR4), cluster of differentiation(CD)-57 and CD-4], and on immunological properties of saliva (IgA levels) in non-surgical periodontal therapy in generalized chronic periodontitis (GCP) patients. Adhesion to buccal epithelial cells (BEC) and the antimicrobial properties of HN019 were also investigated. MATERIALS AND METHODS: Thirty patients were recruited and monitored clinically at baseline (before scaling and root planing-SRP) and after 30 and 90 days. Patients were randomly assigned to Test (SRP+Probiotic, n = 15) or Control (SRP+Placebo, n = 15) group. Probiotic lozenges were used for 30 days. Gingival tissues and saliva were immunologically analyzed. The adhesion of HN019 with or without Porphyromonas gingivalis in BEC and its antimicrobial properties were investigated in in vitro assays. Data were statistically analyzed (p<0.05). RESULTS: Test group presented lower plaque index (30 days) and lower marginal gingival bleeding (90 days) when compared with Control group. Higher BD-3, TLR4 and CD-4 expressions were observed in gingival tissues in Test group than in Control group. HN019 reduced the adhesion of P. gingivalis to BEC and showed antimicrobial potential against periodontopathogens. CONCLUSION: Immunological and antimicrobial properties of B. lactis HN019 make it a potential probiotic to be used in non-surgical periodontal therapy of patients with GCP. CLINICAL RELEVANCE: B. lactis HN019 may be a potential probiotic to improve the effects of non-surgical periodontal therapy. Name of the registry and registration number (ClinicalTrials.gov): "Effects of probiotic therapy in the treatment of periodontitis"-NCT03408548.

Intracranial abscess due to Prevotella bivia: First case report from India.

The association of Prevotella bivia (P. bivia), a Gram negative obligate anaerobic bacillus with brain abscess has been rarely reported. We hereby, report a case of brain abscess in a 50-year-old man, who suffered a head trauma followed by decompression surgery 10 months ago. Aspirated pus sample grew Methicillin resistant Staphylococcus aureus (MRSA) and P. bivia sensitive to metronidazole. The patient recovered well after a brain abscess evacuation surgery and post-operative metronidazole therapy, confirming the pathogenic role of P. bivia in this case.

The usefulness of abscess tonsillectomy followed by intraoral drainage for parapharyngeal abscess concomitant with peritonsillar abscess in the elderly.

Parapharyngeal abscess (PPA) may cause life-threatening complications and peritonsillar abscess (PTA) and tonsillitis frequently precede PPA. The optimal management of PPA caused by PTA has been the subject of debate with respect to the surgical approach. We present three cases of PPA concomitant with PTA in elderly patients. In two cases, the abscesses in parapharyngeal space were drained by abscess tonsillectomy followed by intraoral incision of the tonsillar bed. On the other hand, the third case did not undergo abscess tonsillectomy because of his refusal of surgery and needed extraoral drainage after the aggravation of PPA. Based on the experience of those three cases, it was suggested that abscess tonsillectomy followed by intraoral incision of the tonsillar bed might be a useful surgical approach for the drainage of PPA concomitant with PTA, especially in elderly patients.

Hyperbaric oxygen therapy in a case of cervical abscess extending to anterior mediastinum, with isolation of Prevotella corporis.

We present a case of an odontogenic abscess, first spreading at the lateral cervical level and then in mediastinum. We isolated an anaerobic bacterium, Prevotella corporis, rarely documented in literature. The mortality rates of cervical abscesses secondary to odontogenic infections and complicated by mediastinitis vary from 10% to 40%. Treatment of descending mediastinitis involves multidisciplinary teams such as otorhinolaryngology, thoracic surgeons, infectious disease physicians, anesthetists and intensivists. Due to the combined treatment with surgical drainage within 48 hours of hospitalisation, antibiotics and subsequent hyperbaric oxygen therapy, we have achieved complete recovery of the patient.

Immunological Pathways Triggered by Porphyromonas gingivalis and Fusobacterium nucleatum: Therapeutic Possibilities?

Porphyromonas gingivalis (P. gingivalis) and Fusobacterium nucleatum (F. nucleatum) are Gram-negative anaerobic bacteria possessing several virulence factors that make them potential pathogens associated with periodontal disease. Periodontal diseases are chronic inflammatory diseases of the oral cavity, including gingivitis and periodontitis. Periodontitis can lead to tooth loss and is considered one of the most prevalent diseases worldwide. P. gingivalis and F. nucleatum possess virulence factors that allow them to survive in hostile environments by selectively modulating the host's immune-inflammatory response, thereby creating major challenges to host cell survival. Studies have demonstrated that bacterial infection and the host immune responses are involved in the induction of periodontitis. The NLRP3 inflammasome and its effector molecules (IL-1ß and caspase-1) play roles in the development of periodontitis. We and others have reported that the purinergic P2X7 receptor plays a role in the modulation of periodontal disease and intracellular pathogen control. Caspase-4/5 (in humans) and caspase-11 (in mice) are important effectors for combating bacterial pathogens via mediation of cell death and IL-1ß release. The exact molecular events of the host's response to these bacteria are not fully understood. Here, we review innate and adaptive immune responses induced by P. gingivalis and F. nucleatum infections and discuss the possibility of manipulations of the immune response as therapeutic strategies. Given the global burden of periodontitis, it is important to develop therapeutic targets for the prophylaxis of periodontopathogen infections.

Biochemical characterization of a recombinant Lactobacillus acidophilus strain expressing exogenous FomA protein.

In previous research, to combine the immunogenicity of Fusobacterium nucleatum (F. nucleatum) and the probiotic properties of Lactobacillus acidophilus (L. acidophilus), we constructed a FomA-expressing L. acidophilus strain and assessed its immunogenicity. Our findings indicated that oral administration of the recombinant L. acidophilus strain reduced the risk of periodontal infection by Porphyromonas gingivalis (P. gingivalis) and F. nucleatum. However, because the exogenous FomA is an heterologous protein for the original bacterium, in this study, we assessed whether the biochemical characteristics of the recombinant L. acidophilus strain change due to the expression of the exogenous FomA protein. OBJECTIVES: To test the biochemical characteristics of a recombinant L. acidophilus strain expressing exogenous FomA and assess its antibiotic sensitivity. DESIGNS: We assessed the colony morphology, growth, acid production, and carbohydrate fermentation abilities of the recombinant L. acidophilus strain. In addition, we tested the adhesive ability and antimicrobial activity of the recombinant and assessed its antibiotic sensitivity through a drug susceptibility test. RESULTS: The experimental results showed that the colony and microscopic morphology of the recombinant L. acidophilus strain was consistent with the original strain, and the recombinant strain grew well when cultured under aerobic or anaerobic conditions, exhibiting a growth rate that was identical to that of the standard strain. Similarly, the supernatants of the recombinant L. acidophilus can inhibit the growth of E. coli and P. gingivalis at different concentrations, and the recombinant strain displayed essentially the same drug sensitivity profile as the original L. acidophilus. However, to our surprise, the recombinant strains exhibited a greater adhesion ability than the reference strain. CONCLUSIONS: Our study demonstrated that, in addition to an increased adhesion ability, the recombinant L. acidophilus strain maintained the basic characteristics of the standard strain ATCC 4356, including antibiotic sensitivity. Thus, the recombinant strains have great potential to be utilized as a safe and effective periodontitis vaccine in the future.

Therapeutic effect of bone marrow mesenchymal stem cells pretreated with acetylsalicylic acid on experimental periodontitis in rats.

Periodontitis is a local inflammatory environment with dysregulation of host responses, which results in destruction of periodontal tissues. Mesenchymal stem cells (MSCs) have been proven to play important roles in tissue regeneration by serving as progenitor cells, but its therapeutic outcomes are yet, evaluated variable and unpredictable because of the influence of local inflammation. Acetylsalicylic acid (ASA) has been reported to benefit for MSCs in terms of inflammation control and tissue regeneration. In this study, we aimed to explore the effect of bone marrow mesenchymal stem cells (BMMSCs) pretreated with ASA (ASA-BMMSCs) on periodontal bone repair in a ligature and bacteria-induced periodontitis model in rats. We show herein that, ASA-BMMSCs treatment reduced inflammatory infiltration and alveolar bone loss in periodontitis rats, reflected by immunohistochemistry staining of OPG/RANK-L and Micro-CT. Levels of TNF-α and IL-17 decreased while IL-10 increased after the treatment of ASA-BMMSCs in periodontitis rats. In addition, less osteoclasts number was detected in ASA-BMMSCs treated group. In vitro study showed that ASA facilitated BMMSCs proliferation and differentiation, which might explain the reduced bone loss in periodontitis. These results together suggest that local application of ASA-BMMSCs in periodontal lesion sites is capable of improving inflammatory microenvironment, promoting alveolar bone regeneration, thus leading to a recovery of periodontal homeostasis. Besides, this study also provides us a new idea that a combined application of ASA and BMMSCs may be a novel approach for periodontitis treatment and periodontal bone regeneration.

Infected breast cyst due to Prevotella buccae resistant to metronidazole.

Prevotella buccae is a Gram-negative anaerobic rod involved in some human infections. We report the first case of an infected breast cyst in a non-puerperal women due to this pathogen. A 53-year-old woman presented with pain and a cystic lesion in the right breast. Culture of abscess drainage resulted in isolation of P. buccae. High level of resistance to metronidazole was documented. Treatment with drainage and amoxicillin-clavulanate was established, and improvement of this infection was observed.

A Fatal Aortic Arch Rupture Due to Descending Necrotizing Mediastinitis in a 24-year-old Woman.

Descending necrotizing mediastinitis (DNM) is a life-threatening disease which often develops from a purulent infection of the oral cavity and is associated with high rates of mortality. Here we report the case of a young patient who died from an aortic arch rupture in context of DNM developed from an odontogenic infection caused by Prevotella buccae. Based on the current knowledge on this very rare vascular complication, we discuss factors that may have contributed to this fatal issue and future issues to optimize care provided to patients.

The role of bacteriological studies in the management of peritonsillar abscess.

OBJECTIVE: Since most patients with peritonsillar abscess (PTA) can be successfully treated with surgical drainage and empirical antibiotic therapy, routine bacteriologic studies for all patients with PTA may be unnecessary. This study tried to evaluate which patients with PTA should certainly undergo bacteriologic studies. METHODS: Hundred consecutive patients with PTA were treated and underwent culture tests of purulent contents obtained by surgical drainage between April 2008 and December 2013. RESULTS: In 62 of the 100 patients, 71 pathogenic bacteria were identified; 61 (86%) were Gram-positive cocci (GPC), 8 (11%) were Gram-negative rods (GNR), and 6 (8%) were anaerobes. Normal flora were isolated in 27 patients, and culture results were negative in 11 patients. Although not significant, primary (without prior antibiotic therapy) case (odds ratio (OR)=2.19; 95% CI, 0.95-5.05) and laryngeal edema (OR=2.04; 95% CI, 0.82-5.03) showed a tendency of associations with detection of pathogenic bacteria. After taking into account interactions between smoking habit and laryngeal edema, the covariate-adjusted OR for non-smokers with laryngeal edema was significant and showed a strong relationship (OR=7.43; 95% confidence interval, 1.05-52.73) compared to non-smokers without laryngeal edema. CONCLUSION: Although empirical antibiotic therapy was effective for most of the PTA patients, bacteriologic studies might be indispensable for the patients with laryngeal edema considering the failure of the first treatments. Particularly, the culture tests may be useful for non-smokers with laryngeal edema.

Thoracic empyema caused by Prevotella spp. diagnosed using 16S rDNA sequence analysis.

We describe a case of thoracic empyema in a 76-year-old male with complication of diabetes mellitus and hypertension. His chief complaints were fever and chest pain. The patient was diagnosed as pleural infection according to the pulmonary computed tomography (CT) scan and laboratory results. The patient had persistent fever after the treatment of continuous percutaneous drainage and 1 week of intravenous moxifloxacin. He was then misdiagnosed as tuberculous pleuritis and still had fever after the treatment of 2 weeks' antituberculosis drugs. Repeated cultures of sputum, blood, bronchoalveolar lavage fluid and pleural fluid were all negative. A gram-negative bacillus was found in the pleural pus Gram stain, and it was identified as Prevotella spp. by 16S ribosomal DNA (rDNA) sequence analysis. The patient recovered after further treatment, including CT-induced pleural drain and intravenous imipenem. Totally, he received 2-week imipenem and 1-month metronidazole therapy from the day he was diagnosed with empyema to the termination of treatment. On the subsequent 2-month and 6-month follow-up visits, no recurrence has been reported for this patient. Routine microbiological methods are important in diagnosis of pleural infection, but they have limitations in some cases, especially for anaerobe. Molecular assay based on 16S rDNA is helpful in detecting causative organisms of thoracic empyema.

Evaluation of adjunctive systemic doxycycline with non-surgical periodontal therapy within type 2 diabetic patients.

OBJECTIVES: To evaluate the effects of systemic doxycycline on clinical and microbiological parameters of diabetic subjects with chronic periodontitis. METHODS: This 9-month multi-center, randomized, parallel, single-blinded study was conducted from different hospitals in Riyadh, Saudi Arabia between April 2010 and December 2010. A total of 76 diabetic subjects with chronic periodontitis were randomized into 2 groups: control group (CG) received only scaling and root planing (SRP), and the treatment group (TG) receiving systemic doxycycline during the reevaluation visit 45 days after the completion of SRP. Probing pocket depth, clinical attachment level, gingival index, plaque index, and bleeding on probing were collected at baseline, 45 days after SRP, and one, 3, and 6 months  after the use of systemic doxycycline. Microbiological analysis comprised the detection of Tannerella forsythia (Tf), Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), and Prevotella intermedia (Pi) by polymerase chain reaction method. RESULTS: Sixty-eight (33 CG and 35 TG) subjects completed the study. Greater reduction in the population of Tf, Pg, and Pi were observed in TG compared with CG in the first month after the administration of systemic doxycycline. The TG showed a significant improvement in gingival index scores compared with the CG (p<0.05) by the end of the first and 6 months after the administration of doxycycline. CONCLUSION: Adjunct systemic doxycycline can be associated with a reduction of Tf, Pg, and Pi in the first month after the administration of doxycycline with an improvement in the GI. 

Therapeutic effect of TSG-6 engineered iPSC-derived MSCs on experimental periodontitis in rats: a pilot study.

BACKGROUND: We derived mesenchymal stem cells (MSCs) from rat induced pluripotent stem cells (iPSCs) and transduced them with tumor necrosis factor alpha-stimulated gene-6 (TSG-6), to test whether TSG-6 overexpression would boost the therapeutic effects of iPSC-derived MSCs in experimental periodontitis. METHODS: A total of 30 female Sprague-Dawley (SD) rats were randomly divided into four groups: healthy control group (Group-N, n = 5), untreated periodontitis group (Group-P, n = 5), iPS-MSCs-treated and iPSC-MSCs/TSG-6-treated periodontitis groups (Group-P1 and P2, n = 10 per group). Experimental periodontitis was established by ligature and infection with Porphyromonas gingivalis around the maxillae first molar bilaterally. MSC-like cells were generated from rat iPSCs, and transducted with TSG-6. iPSC-MSCs or iPSC-MSCs/TSG-6 were administrated to rats in Group-P1 or P2 intravenously and topically, once a week for three weeks. Blood samples were obtained one week post-injection for the analysis of serum pro-inflammatory cytokines. All animals were killed 3 months post-treatment; maxillae were then dissected for histological analysis, tartrate-resistant acid phosphatase (TRAP) staining, and morphological analysis of alveolar bone loss. RESULTS: Administration of iPSC-MSC/TSG-6 significantly decreased serum levels of IL-1ß and TNF-α in the Group-P2 rats (65.78 pg/ml and 0.56 pg/ml) compared with those in Group-P (168.31 pg/ml and 1.15 pg/ml respectively) (p<0.05). Both alveolar bone loss and the number of TRAP-positive osteoclasts showed a significant decrease in rats that received iPSC-MSC/TSG-6 treatment compared to untreated rats in Group-P (p<0.05). CONCLUSIONS: We demonstrated that overexpression of TSG-6 in rat iPSC-derived MSCs were capable of decreasing inflammation in experimental periodontitis and inhibiting alveolar bone resorption. This may potentially serve as an alternative stem-cell-based approach in the treatment and regeneration of periodontal tissues.

Cervical necrotizing fasciitis: report of 6 cases and review of literature.

OBJECTIVE: Necrotizing fasciitis in the cervical region is a rare entity, characterized by a fulminant infection that causes extensive necrosis of the subcutaneous tissue and fascial planes, with high mortality and morbidity rates. The origin is generally odontogenic or pharyngeal, involving a mixed flora of microorganisms. Descending infection and mediastinal involvement are usually associated and are the main complications. The aim of the present study was to review the cases treated in our department and analyze diagnosis and treatment, supplementing the understanding of the disease. METHODS: A retrospective study was performed on the clinical records of patients admitted to our center between January 2005 and June 2010 with diagnosis of necrotizing cervical fasciitis. RESULTS: Six clinical records were reviewed. The origin of the infection was mainly oropharyngeal and odontogenic, with a mixed flora of Prevotella, Peptostreptococcus and coagulase-negative Staphylococcus. All patients presented mediastinal involvement: superior mediastinitis in 4 patients and superior and postero-inferior mediastinitis in 2 cases. All patients underwent early drainage by bilateral cervicotomy with mediastinal drainage by a cervical approach in those with superior mediastinal affection, and associated thoracotomy, in a single surgical step, for postero-inferior mediastinitis. Temporary tracheotomy was performed in all cases. All received broad spectrum antibiotics, with a medium hospital stay of 37 days. There were no deaths reported. CONCLUSION: Concerning cervical necrotizing fasciitis, early diagnosis and surgical treatment associated to antibiotics and intensive medical care are essential to obtain a favorable outcome.

[Clinical and microbiological effects of the initial periodontal therapy].

INTRODUCTION: Periodontitis is a destructive inflammatory disease of the tooth-supporting tissues, primarily caused by Gram-negative microorganisms. Thus, the primary objective of cause-related initial periodontal therapy is disruption and removal of the subgingival biofilm. OBJECTIVE: The aim of this study was to evaluate the clinical and microbiological effects of the initial therapy in patients diagnosed with chronic periodontitis. METHODS: Forty patients with chronic periodontitis were included in the study. As a part of the clinical assessment undertaken prior to the initial therapy, as well as one month and three months post-therapy, plaque index, gingival index, papilla bleeding index, probing pocket depth and clinical attachment level were recorded. Microbiological testing was performed prior to the initial therapy and three months after therapy. Polymerase chain reaction assays were used to determine the presence of Porphyromonas gingivalis, Tannerella forsythensis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans. RESULTS: All clinical parameters were significantly reduced after therapy. The prevalence of Aggregatibacter actinomycetemcomitans was reduced by 22.5%, which was a statistically significant decrease compared to the baseline. The prevalence of Porphyromonas gingivalis, Tannerella forsythensis and Prevotella intermedia tended to decrease after therapy; however, the difference did not reach statistical significance. CONCLUSION: The results of the present study demonstrated the beneficial effects of the initial periodontal therapy on both the clinical and microbiological parameters.

Descending necrotizing mediastinitis: a conservative approach.

Descending necrotizing mediastinitis (DNM) is a now-rare complication of dental and pharyngeal infections. Reports in the literature have emphasized the need for early, aggressive surgical intervention. We present a case of DNM with bilateral empyemas that arose secondary to a perforated pharyngeal abscess. The patient was successfully managed conservatively with intravenous antibiotics and intercostal drainage. We conclude that conservative management with antibiotics and image-guided percutaneous pleural drainage may be initially appropriate for the stable patient.

Empyema caused by Prevotella bivia complicating an unusual case of spontaneous chylothorax.

Spontaneous chylothorax is rare in adults. We present an unusual case that was complicated by Prevotella bivia empyema. Full recovery was achieved with chest tube drainage and prompt treatment with intravenous clindamycin.

Protective effect of an egg yolk-derived immunoglobulin (IgY) against Prevotella intermedia-mediated gingivitis.

AIMS: To investigate the effects of an egg yolk-derived immunoglobulin (IgY) specific to Prevotella intermedia in vitro and in vivo. METHODS AND RESULTS: An IgY specific to P. intermedia was produced by immunizing hens with formaldehyde-inactivated P. intermedia and showed high titres when subjected to an ELISA. The obtained IgY inhibited the growth of P. intermedia in a dose-dependent manner at concentrations from 1 to 20 mg ml(-1) in Center for Disease Control and Prevention liquid medium. Forty rats were challenged with P. intermedia on gingivae and then randomly divided into four groups, which were syringed respectively with phosphate-buffered saline, 1 mg ml(-1) of tinidazole, 20 mg ml(-1) of nonspecific IgY and 20 mg ml(-1) of the IgY specific to P. intermedia at a dosage of 300 µl per day. Gingival index (GI), plaque index (PI), bleeding on probing (BOP), counts of white blood cell (WBC) and histopathological slide of the gums were measured after treatment for 15 days. The gingivitis rats treated with the IgY specific to P. intermedia showed significantly decreased GI, PI, BOP and WBC (P < 0·05). Gum histopathology of the treated rats demonstrated a superior protective effect of the specific IgY on P. intermedia-mediated gingivitis. CONCLUSIONS: A new immunoglobulin specific to P. intermedia was developed from egg yolk. This specific IgY can dose-dependently inhibit the growth of P. intermedia and protect rats from gingivitis induced by P. intermedia. SIGNIFICANCE AND IMPACT OF THE STUDY: The new IgY has potential for the treatment of P. intermedia-mediated gingivitis.