Characteristics of the oral and gastric microbiome in patients with early-stage intramucosal esophageal squamous cell carcinoma.

BACKGROUND: Oral microbiome dysbacteriosis has been reported to be associated with the pathogenesis of advanced esophageal cancer. However, few studies investigated the potential role of oral and gastric microbiota in early-stage intramucosal esophageal squamous carcinoma (EIESC). METHOD: A total of 104 samples were collected from 31 patients with EIESC and 21 healthy controls. The compositions of oral and gastric microbiota were analyzed using 16 S rRNA V3-V4 amplicon sequencing. Linear discriminant analysis effect size (LEfSe) analysis was performed to assess taxonomic differences between groups. The correlation between oral microbiota and clinicopathological factors was evaluated using Spearman correlation analysis. Additionally, co-occurrence networks were established and random forest models were utilized to identify significant microbial biomarkers for distinguishing between the EIESC and control groups. RESULTS: A total of 292 oral genera and 223 species were identified in both EIESC and healthy controls. Six oral genera were remarkably enriched in EIESC groups, including the genera Porphyromonas, Shigella, Subdoligranulum, Leptotrichia, Paludibacter, and Odoribacter. LEfSe analysis identified genera Porphyromonas and Leptotrichia with LDA scores > 3. In the random forest model, Porphyromonas endodontalis ranked the top microbial biomarker to differentiate EIESC from controls. The elimination rate of Porphyromonas endodontalis from the oral cavity to the stomach was also dramatically decreased in the EIESC group than controls. In the microbial co-occurrence network, Porphyromonas endodontalis was positively correlated with Prevotella tannerae and Prevotella intermedia and was negatively correlated with Veillonella dispar. CONCLUSION: Our study potentially indicates that the dysbacteriosis of both the oral and gastric microbiome was associated with EIESC. Larger scale studies and experimental animal models are urgently needed to confirm the possible role of microbial dysbacteriosis in the pathogenesis of EIESC. (Chinese Clinical Trial Registry Center, ChiCTR2200063464, Registered 07 September 2022, https://www.chictr.org.cn/showproj.html?proj=178563).

Investigation of periodontal disease development and Porphyromonas gulae FimA genotype distribution in small dogs.

In dogs, Porphyromonas gulae is a major periodontal pathogen with 41-kDa proteins polymerizing to form a filamentous structure called fimbriae or pili, termed FimA. FimA is classified into three genotypes: A, B, and C, and there are combinations of types A, B, C, A/B, A/C, B/C, and A/B/C. Periodontal disease is the most common oral disease in small dogs, but the periodontal disease status and P. gulae colonization at each dog age and breed remain unclear. In this study, we stratified 665 small dogs and analyzed the periodontal status and distribution of P. gulae with each FimA genotype. Dogs with periodontal disease and FimA genotype tended to increase with age. The dogs with at least one FimA genotype had significantly more severe periodontal disease compared with P. gulae-negative dogs (P < 0.01). Additionally, periodontal status was significantly associated with specific FimA genotype distribution in Toy Poodles and Chihuahuas (P < 0.05), whereas there was no such association in Dachshunds. These results suggest that the onset of periodontal disease and P. gulae colonization are related and progress with age. The relationship between periodontal disease and FimA genotype may differ depending on the dog breeds.

Cancer invasion and anaerobic bacteria: new insights into mechanisms.

There is growing evidence that altered microbiota abundance of a range of specific anaerobic bacteria are associated with cancer, including Peptoniphilus spp., Porphyromonas spp., Fusobacterium spp., Fenollaria spp., Prevotella spp., Sneathia spp., Veillonella spp. and Anaerococcus spp. linked to multiple cancer types. In this review we explore these pathogenic associations. The mechanisms by which bacteria are known or predicted to interact with human cells are reviewed and we present an overview of the interlinked mechanisms and hypotheses of how multiple intracellular anaerobic bacterial pathogens may act together to cause host cell and tissue microenvironment changes associated with carcinogenesis and cancer cell invasion. These include combined effects on changes in cell signalling, DNA damage, cellular metabolism and immune evasion. Strategies for early detection and eradication of anaerobic cancer-associated bacterial pathogens that may prevent cancer progression are proposed.

Anti-Citrullinated Peptide Antibodies Control Oral Porphyromonas and Aggregatibacter species in Patients with Rheumatoid Arthritis.

Oral microbiome changes take place at the initiation of rheumatoid arthritis (RA); however, questions remain regarding the oral microbiome at pre-RA stages in individuals with clinically suspect arthralgia (CSA). Two cross-sectional cohorts were selected including 84 Tatarstan women (15 early-RA as compared to individuals with CSA ranging from CSA = 0 [n = 22], CSA = 1 [n = 19], CSA = 2 [n = 11], and CSA ≥ 3 [n = 17]) and 42 women with established RA (median: 5 years from diagnosis [IQ: 2-11]). Amplicon sequence variants (ASVs) obtained from oral samples (16S rRNA) were analyzed for alpha and beta diversity along with the abundance at the genus level. A decrease in oral Porphyromonas sp. is observed in ACPA-positive individuals, and this predominates in early-RA patients as compared to non-RA individuals irrespective of their CSA score. In the RA-established cohort, Porphyromonas sp. and Aggregatibacter sp. reductions were associated with elevated ACPA levels. In contrast, no associations were reported when considering individual, genetic and clinical RA-associated factors. Oral microbiome changes related to the genera implicated in post-translational citrullination (Porphyromonas sp. and Aggregatibacter sp.) characterized RA patients with elevated ACPA levels, which supports that the role of ACPA in controlling the oral microbiome needs further evaluation.

Green tea catechins inhibit Porphyromonas gulae LPS-induced inflammatory responses in human gingival epithelial cells.

OBJECTIVES: To determine the anti-inflammatory effects of green tea catechins in immortalized human gingival epithelial cells (Ca9-22) stimulated with Porphyromonas gulae lipopolysaccharide (LPS). METHODS: Ca9-22 cells were incubated with P. gulae LPS (10 µg/ml) with or without green tea catechins, epigallocatechin-3-gallate (EGCg), epigallocatechin (EGC), epicatechin-3-gallate (ECG), and epicatechin (EC) (each at 50 µM), for 6 or 24 h. Real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay were used to determine the induction of cyclooxygenase 2 (COX2), tumor necrosis factor alpha (TNF-ɑ), interleukin 6 (IL-6), and IL-8. Furthermore, the expression of toll-like receptors (TLRs) 2 and 4 was examined using real-time PCR and western blotting analysis, and phosphorylation of the p38 and ERK1/2 was examined using western blotting analysis. RESULTS: At the mRNA and protein levels, EGCg, EGC, ECG, and EC were found to significantly inhibit COX2, TNF-ɑ, IL-6, and IL-8. Furthermore, the levels of ERK1/2 and p38 phosphorylation induced by P. gulae LPS were decreased following the addition of each of the catechins, as well as TLR2 and 4 mRNA and protein. CONCLUSIONS: These findings indicate that green tea catechins are potent inhibitors of inflammatory responses induced by P. gulae LPS, and may also be useful for prevention and/or attenuation of periodontitis.

A phosphopantetheinyl transferase gene restricted to Porphyromonas.

The phosphopantetheinyl transferases (PPTases) catalyze the post-translational modification of carrier proteins (CPs) from fatty acid synthases (FASs) in primary metabolism and from polyketide synthases (PKSs) and non-ribosomal polypeptide synthases (NRPSs) in secondary metabolism. Based on the conserved sequence motifs and substrate specificities, two types (AcpS-type and Sfp-type) of PPTases have been identified in prokaryotes. We present here that Porphyromonas gingivalis, the keystone pathogen in chronic periodontitis, harbors merely one PPTase, namely PptP. Complementation and gene deletion experiments clearly show that PptP can replace the function of Escherichia coli AcpS and is essential for the growth of P. gingivalis. Purified PptP transfers the 4-phosphopantetheine moiety of CoA to inactive apo-acyl carrier protein (ACP) to form holo-ACP, which functions as an active carrier of the acyl intermediates of fatty acid synthesis. Moreover, PptP exhibits broad substrate specificity, modifying all ACP substrates tested and catalyzing the transfer of coenzyme A (CoA) derivatives. The lack of sequence alignment with known PPTases together with phylogenetic analyses revealed PptP as a new class of PPTases. Identification of the new PPTase gene pptP exclusive in Porphyromonas species reveals a potential target for treating P. gingivalis infections.

Porphyromonas pasteri and Prevotella nanceiensis in the sputum microbiota are associated with increased decline in lung function in individuals with cystic fibrosis.

Although anaerobic bacteria exist in abundance in cystic fibrosis (CF) airways, their role in disease progression is poorly understood. We hypothesized that the presence and relative abundance of the most prevalent, live, anaerobic bacteria in sputum of adults with CF were associated with adverse clinical outcomes. This is the first study to prospectively investigate viable anaerobic bacteria present in the sputum microbiota and their relationship with long-term outcomes in adults with CF. We performed 16S rRNA analysis using a viability quantitative PCR technique on sputum samples obtained from a prospective cohort of 70 adults with CF and collected clinical data over an 8 year follow-up period. We examined the associations of the ten most abundant obligate anaerobic bacteria present in the sputum with annual rate of FEV1 change. The presence of Porphyromonas pasteri and Prevotella nanceiensis were associated with a greater annual rate of FEV1 change; -52.3 ml yr-1 (95 % CI-87.7;-16.9), -67.9 ml yr-1 (95 % CI-115.6;-20.1), respectively. Similarly, the relative abundance of these live organisms were associated with a greater annual rate of FEV1 decline of -3.7 ml yr-1 (95 % CI: -6.1 to -1.3, P=0.003) and -5.3 ml yr-1 (95 % CI: -8.7 to -1.9, P=0.002) for each log2 increment of abundance, respectively. The presence and relative abundance of certain anaerobes in the sputum of adults with CF are associated with a greater rate of long-term lung function decline. The pathogenicity of anaerobic bacteria in the CF airways should be confirmed with further longitudinal prospective studies with a larger cohort of participants.

Effect of TrisEDTA and Chlorhexidine 0.12% on an In Vitro-Defined Biofilm Representing the Subgingival Plaque Biofilm of the Dog.

This study was designed to investigate the effects of chlorhexidine 0.12%, TrisEDTA (tromethamine ethylenediamintetraacetic acid), and a combination of chlorhexidine 0.12% and TrisEDTA on an in vitro plaque biofilm model comprised of three bacterial species commonly found in canine subgingival plaque. Porphyromonas gulae, Actinomyces canis, and Neisseria canis were grown in a biofilm on polished hydroxyapatite coated titanium alloy pucks for 72 h prior to exposure to one of four test solutions: TrisEDTA, chlorhexidine 0.12%, a combination of TrisEDTA and chlorhexidine 0.12%, or sterile deionized water as a control. Following exposure to the test solution, a sample was collected of the biofilm either immediately or following 24 h of additional incubation in a broth medium. Lower numbers of CFU/mL of Porphyromonas gulae resulted when the biofilm was treated with a solution of chlorhexidine 0.12% and TrisEDTA compared to with chlorhexidine 0.12% alone, TrisEDTA alone, or the control and so this solution can be said to be synergistic against Porphyromonas gulae in this controlled in vitro model. Greater reductions in the numbers of CFU/mL of Actinomyces canis and Neisseria canis resulted from treatment with chlorhexidine 0.12% alone than if treated with the combination of TrisEDTA and chlorhexidine 0.12%. When treated biofilm samples were allowed 24 h of additional growth in fresh media, greater variance resulted and this variance highlights the complex dynamics involved in bacterial growth within a biofilm.

The bacterial microbiota of Hunner lesion interstitial cystitis/bladder pain syndrome.

OBJECTIVE: To undertake the first comprehensive evaluation of the urinary microbiota associated with Hunner lesion (HL) interstitial cystitis/bladder pain syndrome (IC/BPS). Despite no previous identification of a distinct IC/BPS microbial urotype, HL IC/BPS, an inflammatory subtype of IC/BPS, was hypothesized most likely to be associated with a specific bacterial species or microbial pattern. PARTICIPANTS AND METHODS: The bacterial microbiota of midstream urine specimens from HL IC/BPS and age- and gender-matched IC/BPS patients without HL (non-HL IC/BPS) were examined using the pan-bacterial domain clinical-level molecular diagnostic Pacific Biosciences full-length 16S gene sequencing protocol, informatics pipeline and database. We characterized the differential presence, abundances, and diversity of species, as well as gender-specific differences between and among HL and non-HL IC/BPS patients. RESULTS: A total of 59 patients with IC/BPS were enrolled (29 HL, 30 non-HL; 43 women, 16 men) from a single centre and the microbiota in midstream urine specimens was available for comparison. The species abundance differentiation between the HL and non-HL groups (12 species) was not significantly different after Bonferroni adjustments for multiple comparisons. Similarly, the nine differentiating species noted between female HL and non-HL patients were not significantly different after similar statistical correction. However, four species abundances (out of the 10 species differences identified prior to correction) remained significantly different between male HL and non-HL subjects: Negativicoccus succinivorans, Porphyromonas somerae, Mobiluncus curtisii and Corynebacterium renale. Shannon diversity metrics showed significantly higher diversity among HL male patients than HL female patients (P = 0.045), but no significant diversity differences between HL and non-HL patients overall. CONCLUSIONS: We were not able to identify a unique pathogenic urinary microbiota that differentiates all HL from all non-HL IC/BPS. It is likely that the male-specific differences resulted from colonization/contamination remote from the bladder. We were not able to show that bacteria play an important role in patients with HL IC/BPS.

Systemic burden and cardiovascular risk to Porphyromonas species in apical periodontitis.

OBJECTIVE: Porphyromonas (P.) species (spp.) are a major etiological agent of apical periodontitis (AP), which in turn represents a risk factor for cardiovascular diseases. This study explored the associations between endodontic infection with Porphyromonas species, the systemic bacterial burden, and cardiovascular risk, based on high-sensitivity C-reactive protein (hsCRP), in young adults with AP. MATERIALS AND METHODS: Cross-sectional study. Otherwise, healthy individuals with AP and controls (n = 80, ≤ 40 years) were recruited at the University Dental Clinic. Oral parameters and classic cardiovascular risk factors were registered. Endodontic Porphyromonas endodontalis and Porphyromonas gingivalis were identified using conventional PCR. Serum concentrations of anti-P. endodontalis and anti-P. gingivalis antibodies, and endotoxins were determined through ELISA and Limulus-amebocyte assays. Serum hsCRP was determined for cardiovascular risk stratification. RESULTS: Intracanal detection of P. endodontalis and P. gingivalis in AP were 33.3% and 22.9%, respectively. Serum anti-P. endodontalis and anti-P. gingivalis IgG was higher in AP than controls (p < 0.05 and p = 0.057, respectively). Intracanal P. endodontalis associated with higher endotoxemia (p < 0.05). Among endodontic factors, the presence (OR 4.2-5.5, p < 0.05) and the number of apical lesions (OR 2.3, p < 0.05) associated with moderate-severe cardiovascular risk, whereas anti-P. endodontalis IgG were protective (OR 0.3, p > 0.05). CONCLUSIONS: AP and infection with P. endodontalis positively associated with cardiovascular risk based on hsCRP levels and endotoxemia, respectively, whereas anti-P. endodontalis IgG response seems to be protective against low-grade systemic inflammation. CLINICAL RELEVANCE: Apical periodontitis and endodontic P. endodontalis can influence the systemic burden with impact on the surrogate cardiovascular risk marker hsCRP, providing mechanistic links.

Duodenal Dysbiosis and Relation to the Efficacy of Proton Pump Inhibitors in Functional Dyspepsia.

Proton pump inhibitors (PPI) may improve symptoms in functional dyspepsia (FD) through duodenal eosinophil-reducing effects. However, the contribution of the microbiome to FD symptoms and its interaction with PPI remains elusive. Aseptic duodenal brushings and biopsies were performed before and after PPI intake (4 weeks Pantoprazole 40 mg daily, FD-starters and controls) or withdrawal (2 months, FD-stoppers) for 16S-rRNA sequencing. Between- and within-group changes in genera or diversity and associations with symptoms or duodenal factors were analyzed. In total, 30 controls, 28 FD-starters and 19 FD-stoppers were followed. Mucus-associated Porphyromonas was lower in FD-starters vs. controls and correlated with symptoms in FD and duodenal eosinophils in both groups, while Streptococcus correlated with eosinophils in controls. Although clinical and eosinophil-reducing effects of PPI therapy were unrelated to microbiota changes in FD-starters, increased Streptococcus was associated with duodenal PPI effects in controls and remained higher despite withdrawal of long-term PPI therapy in FD-stoppers. Thus, duodenal microbiome analysis demonstrated differential mucus-associated genera, with a potential role of Porphyromonas in FD pathophysiology. While beneficial effects of short-term PPI therapy were not associated with microbial changes in FD-starters, increased Streptococcus and its association with PPIeffects in controls suggest a role for duodenal dysbiosis after long-term PPI therapy.

Desulfovibrio fairfieldensis adhesion on implantable titanium used in odontology: a preliminary study.

The study presented here aimed to assess the ability of Desulfovibrio fairfieldensis bacteria to adhere to and form biofilm on the structure of titanium used in implants. D. fairfieldensis was found in the periodontal pockets in the oral environment, indicating that these bacteria can colonize the implant-bone interface and consequently cause bone infection and implant corrosion. Plates of implantable titanium, of which surfaces were characterized by scanning electronic microscopy and Raman spectroscopy, were immersed in several suspensions of D. fairfieldensis cells containing potassium nitrate on the one hand, and artificial saliva or a sulfato-reducing bacterial culture medium on the other hand. Following various incubation timepoints bacteria were counted in different media to determine their doubling time and titanium samples are checked for and determination of the total number of adhered bacteria and biofilm formation. Adhesion of D. fairfieldensis on titanium occurs at rates ranging from 2.105 to 4.6.106 bacteria h-1cm-2 in the first 18 h of incubation on both native and implantable titanium samples. Following that time, the increase in cell numbers per h and cm2 is attributed to growth in adhered bacteria. After 30 days of incubation in a nutrient-rich medium, dense biofilms are observed forming on the implant surface where bacteria became embedded in a layer of polymers D. fairfieldensis is able of adhering to an implantable titanium surface in order to form a biofilm. Further studies are still necessary, however, to assess whether this adhesion still occurs in an environment containing saliva or serum proteins that may alter the implant surface.

Potential Roles of the Free Salivary Microbiome Dysbiosis in Periodontal Diseases.

Saliva is a vital mediator in the oral cavity. The dysbiosis of free bacteria in saliva might be related to the onset, development, prognosis, and recurrence of periodontal diseases, but this potential relationship is still unclear. The objective of this study was to investigate the potential roles of the free salivary microbiome in different periodontal statuses, their reaction to nonsurgical periodontal therapy, and differences between diseased individuals after treatment and healthy persons. We recruited 15 healthy individuals, 15 individuals with gingivitis, and 15 individuals with stage I/II generalized periodontitis. A total of 90 unstimulated whole saliva samples were collected and sequenced using full-length bacterial 16S rRNA gene sequencing. We found that as the severity of disease increased, from healthy to gingivitis and periodontitis, the degree of dysbiosis also increased. A higher abundance of Prevotella intermedia and Catonella morbi and a lower abundance of Porphyromonas pasteri, Prevotella nanceiensis, and Haemophilus parainfluenzae might be biomarkers of periodontitis, with an area under curve (AUC) reaching 0.9733. When patients received supragingival scaling, there were more pathogens related to recolonization in the saliva of periodontitis patients than in healthy persons. Even after effective nonsurgical periodontal therapy, individuals with periodontitis displayed a more dysbiotic and pathogenic microbial community in their saliva than healthy individuals. Therefore, the gradual transition in the entire salivary microbial community from healthy to diseased includes a gradual shift to dysbiosis. Free salivary pathogens might play an important role in the recolonization of bacteria as well as the prognosis and recurrence of periodontal diseases.

The feature of cervical microbiota associated with the progression of cervical cancer among reproductive females.

OBJECTIVES: The aim of this study was to characterize cervical microbiome feature of reproductive-age women in the progression of squamous intraepithelial lesions (SIL) to cervical cancer. METHODS: We characterized the 16S rDNA cervical mucus microbiome in 94 participants (age from 18 to 52), including 13 cervical cancer (CA), 31 high-grade SIL (HSIL), 10 low-grade SIL (LSIL), 12 HPV-infected (NH) patients and 28 healthy controls (NN). Alpha (within sample) diversity was examined by Shannon and Simpson index, while Beta (between sample) diversity by principle coordinate analysis (PCoA) of weighted Unifrac distances. Relative abundance of microbial taxa was compared using Linear Discriminant Analysis Effect Size (LEfSe). Co-occurrence analysis was performed to identify correlation among marker genera, and Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) to explore functional features and pathways of cervical microbiota. RESULTS: Alpha diversity(p < 0.05) was higher in severer cervical pathology with lower relative abundance of Lactobacillus as well as higher of anaerobes. Beta diversity (p < 0.01) was significantly different. Marker genera were identified including Porphyromonas, Prevotella and Campylobacter of CA and Sneathia of HSIL. The correlation of differential functional pathways with Prevotella was opposite to that with Lactobacillus. CONCLUSION: Our study suggests differences in cervical microbiota diversity and relative abundance of reproductive-age females in different stages of cervical carcinogenesis. Marker genera might participate in the lesion progression and will be helpful for diagnosis, prevention and treatment. These findings may lead the way to further study of the cervical microbiome in development of cervical cancer.

Gut bacteria identified in colorectal cancer patients promote tumourigenesis via butyrate secretion.

Emerging evidence is revealing that alterations in gut microbiota are associated with colorectal cancer (CRC). However, very little is currently known about whether and how gut microbiota alterations are causally associated with CRC development. Here we show that 12 faecal bacterial taxa are enriched in CRC patients in two independent cohort studies. Among them, 2 Porphyromonas species are capable of inducing cellular senescence, an oncogenic stress response, through the secretion of the bacterial metabolite, butyrate. Notably, the invasion of these bacteria is observed in the CRC tissues, coinciding with the elevation of butyrate levels and signs of senescence-associated inflammatory phenotypes. Moreover, although the administration of these bacteria into ApcΔ14/+ mice accelerate the onset of colorectal tumours, this is not the case when bacterial butyrate-synthesis genes are disrupted. These results suggest a causal relationship between Porphyromonas species overgrowth and colorectal tumourigenesis which may be due to butyrate-induced senescence.

Gut Microbiota Serves a Predictable Outcome of Short-Term Low-Carbohydrate Diet (LCD) Intervention for Patients with Obesity.

To date, much progress has been made in dietary therapy for obese patients. A low-carbohydrate diet (LCD) has reached a revival in its clinical use during the past decade with undefined mechanisms and debatable efficacy. The gut microbiota has been suggested to promote energy harvesting. Here, we propose that the gut microbiota contributes to the inconsistent outcome under an LCD. To test this hypothesis, patients with obesity or patients who were overweight were randomly assigned to a normal diet (ND) or an LCD group with ad libitum energy intake for 12 weeks. Using matched sampling, the microbiome profile at baseline and end stage was examined. The relative abundance of butyrate-producing bacteria, including Porphyromonadaceae Parabacteroides and Ruminococcaceae Oscillospira, was markedly increased after LCD intervention for 12 weeks. Moreover, within the LCD group, participants with a higher relative abundance of Bacteroidaceae Bacteroides at baseline exhibited a better response to LCD intervention and achieved greater weight loss outcomes. Nevertheless, the adoption of an artificial neural network (ANN)-based prediction model greatly surpasses a general linear model in predicting weight loss outcomes after LCD intervention. Therefore, the gut microbiota served as a positive outcome predictor and has the potential to predict weight loss outcomes after short-term LCD intervention. Gut microbiota may help to guide the clinical application of short-term LCD intervention to develop effective weight loss strategies. (This study has been registered at the China Clinical Trial Registry under approval no. ChiCTR1800015156). IMPORTANCE Obesity and its related complications pose a serious threat to human health. Short-term low-carbohydrate diet (LCD) intervention without calorie restriction has a significant weight loss effect for overweight/obese people. Furthermore, the relative abundance of Bacteroidaceae Bacteroides is a positive outcome predictor of individual weight loss after short-term LCD intervention. Moreover, leveraging on these distinct gut microbial structures at baseline, we have established a prediction model based on the artificial neural network (ANN) algorithm that could be used to estimate weight loss potential before each clinical trial (with Chinese patent number 2021104655623). This will help to guide the clinical application of short-term LCD intervention to improve weight loss strategies.

Porphyromonas spp., Fusobacterium spp., and Bacteroides spp. dominate microbiota in the course of macropod progressive periodontal disease.

Macropod progressive periodontal disease (MPPD) is a necrotizing, polymicrobial, inflammatory disease commonly diagnosed in captive macropods. MPPD is characterized by gingivitis associated with dental plaque formation, which progresses to periodontitis and then to osteomyelitis of the mandible or maxilla. However, the underlying microbial causes of this disease remain poorly understood. In this study, we collected 27 oral plaque samples and associated clinical records from 22 captive Macropodidae and Potoroidae individuals that were undergoing clinical examination at Adelaide and Monarto Zoos in South Australia (15 healthy, 7 gingivitis and 5 periodontitis-osteomyelitis samples). The V3-V4 region of the 16S ribosomal RNA gene was sequenced using an Illumina Miseq to explore links between MPPD and oral bacteria in these animals. Compositional differences were detected between the microbiota of periodontitis-osteomyelitis cases compared to healthy samples (p-value with Bonferroni correction < 0.01), as well as gingivitis cases compared to healthy samples (p-value with Bonferroni correction < 0.05) using Permutational Multivariate Analysis of Variance (PERMANOVA). An overabundance of Porphyromonas, Fusobacterium, and Bacteroides taxa was also identified in animals with MPPD compared to healthy individuals using linear discriminant analysis effect size (LEfSe; p = < 0.05). An increased abundance of Desulfomicrobium also was detected in MPPD samples (LEfSe; p < 0.05), which could potentially reflect differences in disease progression. This is the first microbiota analysis of MPPD in captive macropods, and these results support a polymicrobial pathogenesis of MPPD, suggesting that the microbial interactions underpinning MPPD may be more complex than previously documented.

A rare cause of bacteremia due to Porphyromonas asaccharolytica in a patient with necrotizing fasciitis.

Porphyromonas species are Gram-negative anaerobic bacilli mainly involved in human periodontal diseases. We report an uncommon case of bacteremia due to P. asaccharolytica in a patient with necrotizing fasciitis. A 52-year-old woman with a history of diabetes mellitus was admitted for an extensive necrotizing lesion on the left lower limb. After she developed septic shock, two sets of blood cultures were taken. Anaerobic bottles yielded a pure culture of a microorganism initially identified as P. uenonis by MALDI-TOF MS but with a low log score, and a gene sequencing technique was therefore applied, identifying the isolate as P. asaccharolytica. Only resistance to penicillin and clindamycin was documented. Treatment with meropenem was administered, and the patient was discharged following her recovery.

Exploring the signature gut and oral microbiome in individuals of specific Ayurveda prakriti.

Diagnosis and treatment of various diseases in Ayurveda, the Indian system of medicine, relies on 'prakriti' phenotyping of individuals into predominantly three constitutions, kapha, pitta and vata. Recent studies propose that microbiome play an integral role in precision medicine. A study of the relationship between prakriti - the basis of personalized medicine in Ayurveda and that of gut microbiome, and possible biomarker of an individual's health, would vastly improve precision therapy. Towards this, we analyzed bacterial metagenomes from buccal (oral microbiome) and fecal (gut microbiome) samples of 272 healthy individuals of various predominant prakritis. Major bacterial genera from gut microbiome included Prevotella, Bacteroides and Dialister while oral microbiome included Streptococcus, Neisseria, Veilonella, Haemophilus, Porphyromonas and Prevotella. Though the core microbiome was shared across all individuals, we found prakriti specific signatures such as preferential presence of Paraprevotella and Christensenellaceae in vata individuals. A comparison of core gut microbiome of each prakriti with a database of 'healthy' microbes identified microbes unique to each prakriti with functional roles similar to the physiological characteristics of various prakritis as described in Ayurveda. Our findings provide evidence to Ayurvedic interventions based on prakriti phenotyping and possible microbial biomarkers that can stratify the heterogenous population and aid in precision therapy.

The Fecal Microbiota Is Already Altered in Normoglycemic Individuals Who Go on to Have Type 2 Diabetes.

Objective: Mounting evidence has suggested a link between gut microbiome characteristics and type 2 diabetes (T2D). To determine whether these alterations occur before the impairment of glucose regulation, we characterize gut microbiota in normoglycemic individuals who go on to develop T2D. Methods: We designed a nested case-control study, and enrolled individuals with a similar living environment. A total of 341 normoglycemic individuals were followed for 4 years, including 30 who developed T2D, 33 who developed prediabetes, and their matched controls. Fecal samples (developed T2D, developed prediabetes and controls: n=30, 33, and 63, respectively) collected at baseline underwent metagenomics sequencing. Results: Compared with matched controls, individuals who went on to develop T2D had lower abundances of Bifidobacterium longum, Coprobacillus unclassified, and Veillonella dispar and higher abundances of Roseburia hominis, Porphyromonas bennonis, and Paraprevotella unclassified. The abundance of Bifidobacterium longum was negatively correlated with follow-up blood glucose levels. Moreover, the microbial Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of carbohydrate metabolism, methane metabolism, amino acid metabolism, fatty acid metabolism, and membrane transport were changed between the two groups. Conclusions: We found that fecal microbiota of healthy individuals who go on to develop T2D had already changed when they still were normoglycemic. These alterations of fecal microbiota might provide insights into the development of T2D and a new perspective for identifying individuals at risk of developing T2D.