Bacterial community structure of Physalis peruviana L. fruit exocarp and the presence of pathogens with possible implications on food safety.

Introduction: Cape gooseberry (Physalis peruviana L.) is a wellconsumed crop in Ecuador, whose fruits are abundant in bioactive molecules. Its rapid post-harvest deterioration and safety limit its market potential. Methodology: To gather baseline data on the prevalence of bacterial taxa among groups, we employed 16S ribosomal RNA (16S rRNA) amplicon gene sequencing to detect changes in the bacterial community structure in cape gooseberry fruits harvested from an organic farm production system (# 270 samples x two ripeness stages), and fruits obtained from an open-air market (#270). Results: This is the first report of bacterial taxa inhabiting cape gooseberry fruits. Shannon's diversity index revealed that the fruits purchased from the market and the unripe stage had the highest level of bacterial diversity (average Shannon indices of 3.3 and 3.1) followed by those collected from the field at the mature ripe stage (2.07). Alpha diversity analysis indicated that there were no significant differences in the number of taxa or evenness within the sample, whereas there was a significant difference in beta diversity between the groups. Rhizobiaceae was the most abundant family in fruits originating from the field regardless of the ripe stage, while Acetobacteraceae, Pseudomonadaceae, Fusobacteriaceae, Bacteroidaceae, and Erwiniaceae were the most abundant families in the market group. At the genus level, Liberibacter was the most abundant phytopathogen in fruits originating from the field, while Gluconobacter was the most abundant in samples collected from the market. The phytopathogen Candidatus_Liberibacter was the most abundant in samples collected from the field, while the fruits purchased from the market stands contained opportunistic enteric pathogens such as Escherichia vulneris, Klebsiella pneumoniae, and K. variicola, their relative abundance varied with the sample. In addition, potential pathogens of animal origin such as Fusobacterium necrophorum, Porphyromonas levii, Helcococcus ovis, and Trueperella pyogenes were found in almost all samples at varying relative abundance. Conclusion: Our study provides basic information on the microbiome of cape gooseberries from agriculture fields to the table along with the detection of several pathogenic microorganisms with possible impact on food safety and public health therefore, strategies for reducing bacterial contamination in both farm and retail markets are compulsory.

Co-Culture of P. gingivalis and F. nucleatum Synergistically Elevates IL-6 Expression via TLR4 Signaling in Oral Keratinocytes.

Periodontitis, characterized by persistent inflammation in the periodontium, is intricately connected to systemic diseases, including oral cancer. Bacteria, such as Porphyromonas gingivalis and Fusobacterium nucleatum, play a pivotal role in periodontitis development because they contribute to dysbiosis and tissue destruction. Thus, comprehending the interplay between these bacteria and their impacts on inflammation holds significant relevance in clinical understanding and treatment advancement. In the present work, we explored, for the first time, their impacts on the expressions of pro-inflammatory mediators after infecting oral keratinocytes (OKs) with a co-culture of pre-incubated P. gingivalis and F. nucleatum. Our results show that the co-culture increases IL-1ß, IL-8, and TNF-α expressions, synergistically augments IL-6, and translocates NF-kB to the cell nucleus. These changes in pro-inflammatory mediators-associated with chronic inflammation and cancer-correlate with an increase in cell migration following infection with the co-cultured bacteria or P. gingivalis alone. This effect depends on TLR4 because TLR4 knockdown notably impacts IL-6 expression and cell migration. Our study unveils, for the first time, crucial insights into the outcomes of their co-culture on virulence, unraveling the role of bacterial interactions in polymicrobial diseases and potential links to oral cancer.

Efecto Antibacteriano del Extracto Etanólico de Equisetum giganteum L. "Cola de Caballo" Frente al Fusobacterium nucleatum, Microorganismo Asociado a la Enfermedad Periodontal

La fitoterapia aplicada a la Odontología se presenta como una eficaz alternativa de tratamiento frente a las enfermedades periodontales (EP) porque busca utilizar los principios activos de las plantas medicinales que se encuentran en gran cantidad en la naturaleza, dándole así las características de ser más asequibles y de menor costo, para combatir los microorganismos patógenos causantes de las EP. El objetivo del estudio fue determinar el efecto antibacteriano in vitro del extracto etanólico de Equisetum giganteum L. frente a cepas ATCC de Fusobacterium nucleatum. El estudio fue de tipo experimental no probabilístico y estuvo constituido en total por 10 placas Petri sembradas con F. nucleatum. Se utilizó extracto etanólico de E. giganteum L. en las concentraciones de 100, 50, 25, 12.5 y 6.25 %. Se utilizó el método de difusión en agar y se incubaron 10 placas a 37 °C durante 07 días. Se midieron los halos de inhibición con un vernier digital, siendo estos datos posteriormente analizados. No se evidenciaron halos de inhibición significativos en ninguno de los discos embebidos con las diferentes concentraciones en las 10 placas Petri sembradas con F. nucleatum, pero sin con la clorhexidina, agente química utilizado como control positivo. En conclusión no se determinó un efecto antibacteriano in vitro del extracto etanólico de E. giganteum L. frente a F. nucleatum, en ninguna de sus concentraciones.

Phytotherapy applied to Dentistry is presented as an effective alternative treatment against periodontal diseases (PD) because it seeks to use the active ingredients of medicinal plants that are found in large quantities in nature, thus giving it the characteristics of being more affordable. and at a lower cost, to combat the pathogenic microorganisms that cause PE. Objective: to determine the in vitro antibacterial effect of the ethanolic extract of Equisetum giganteum L. against ATCC strains of Fusobacterium nucleatum. Material and methods: The study was of a non- probabilistic experimental type and consisted of a total of 10 Petri dishes seeded with F. nucleatum. Ethanolic extract of E. giganteum L. was used in concentrations of 100, 50, 25, 12.5 and 6.25 %. The agar diffusion method was used and 10 plates were incubated at 37 °C for 07 days. The inhibition halos were measured with a digital vernier, and these data were subsequently analyzed. Results: No significant inhibition halos were found in any of the embedded disks with the different concentrations in the 10 Petri dishes seeded with F. nucleatum, but without chlorhexidine, the chemical agent used as a positive control. Conclusions: an in vitro antibacterial effect of the ethanolic extract of E. giganteum L. was not determined against F. nucleatum, in any of its concentrations.

Antineoplastic therapy in childhood cancer patients presents a negative impact in the periodontal tissues: a cohort study.

OBJECTIVES: To investigate the effect of antineoplastic therapy (AT) in the periodontal tissues of childhood cancer (CC) patients. MATERIALS AND METHODS: Seventy-two individuals were divided into CC (n=36) and healthy individuals (control group-CG, n=36). Demographics, hygiene habits, CC type, and AT were collected. Salivary flow and the presence and concentration of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia, and Fusobacterium nucleatum were analyzed. Clinical evaluation included plaque (PI) and gingival indexes (GI), periodontal probing depth (PPD), and clinical attachment level (CAL). Patients were classified into periodontal health, gingivitis, or periodontitis. Descriptive statistics, T test, Mann-Whitney test, chi-square, Fisher's exact test, and two-way analysis of variance were used (p<0.05). RESULTS: The mean age of the patients was similar (CC 12.0±3.9 years and CG 12.0±4.0 years). In the CC group, all patients underwent chemotherapy and nine radiotherapy. Color/race, income, and family education showed significant differences between groups. There was no difference between groups in salivary flow. Higher levels of Fusobacterium nucleatum were seen in CC (p=0.02). Significant difference between groups was found for PI (CC: 30.5%, CG: 22.6%), GI (CC: 28.8%, CG: 17.3%), PPD (CC: 1.77 mm, CG: 1.61 mm), and CAL (CC: 1.77 mm, CG: 1.57 mm), periodontal health (CC: 3, CG: 7), gingivitis (CC: 16, CG: 24), or periodontitis (CC: 17, CG: 5). CONCLUSION: AT in CC patients presents a negative impact in the periodontal and microbiological parameters. CLINICAL RELEVANCE: Childhood cancer individuals showed worse periodontal parameters and higher levels of Fusobacterium nucleatum in the saliva when compared to healthy individuals.

A new model of in vitro dentin intratubular contamination for Fusobacterium nucleatum: Validation by confocal laser scanning microscopy.

Objectives: To test and validate a new protocol for in vitro contamination of dentinal tubules using Fusobacterium nucleatum (F. nucleatum) by confocal laser scanning microscopy (CLSM), in addition to evaluating the effectiveness of conventional endodontic irrigants such as sodium hypochlorite (NaOCl) and chlorhexidine (CLX) on this biofilm. Material and methods: Thirty lower premolars were contaminated with F. nucleatum (ATCC 51190) for 7 days under anaerobic conditions using the proposed new model. The specimens were divided into a control group and experimental groups, according to the irrigants: NaOCl 2.5% and CLX 2%. Then, the samples were submitted for analysis by CLSM and the LIVE/DEAD technique to quantify bacterial viability. Data normality was verified by the Shapiro-Wilk test. Intragroup and intergroup comparisons were performed using the Kruskal-Wallis test, followed by Dunn's post-test. Results: The CLSM images obtained demonstrated the effectiveness of the proposed new contamination protocol, with a high percentage of viable bacteria in relation to the treated groups (p < 0.05). Lower viability values were observed for the 2.5% NaOCl group. Conclusion: The new contamination protocol resulted in a high and homogeneous percentage of viable bacteria in the dentinal tubules in all specimens evaluated. Both irrigating solutions proved to be effective in reducing the intratubular microbiota, especially 2.5% NaOCl.

Ruminal fermentation pattern of acidosis-induced cows fed either monensin or polyclonal antibodies preparation against several ruminal bacteria.

This study was designed to evaluate a spray-dried multivalent polyclonal antibody preparation (PAP) against lactate-producing bacteria as an alternative to monensin (MON) to control ruminal acidification. Holstein cows (677 ± 98 kg) fitted with ruminal cannulas were allocated in an incomplete Latin square design with two 20 days period. Cows were randomly assigned to control (CTL), PAP, or MON treatments. For each period, cows were fed a forage diet in the first 5 days (d-5 to d-1), composed of sugarcane, urea and a mineral supplement, followed by a 74% concentrate diet for 15 days (d 0 to d 14). There were no treatment main effects (P > 0.05) on dry matter intake (DMI) and microbial protein synthesis. However, there was a large peak (P < 0.01) of intake on d 0 (18.29 kg), followed by a large decline on d 1 (3.67 kg). From d2, DMI showed an increasing pattern (8.34 kg) and stabilized around d 8 (12.96 kg). Higher mean pH was measured (P < 0.01) in cattle-fed MON (6.06 vs. PAP = 5.89 and CTL = 5.91). The ruminal NH3-N concentration of CTL-fed cows was lower (P < 0.01) compared to those fed MON or PAP. The molar concentration of acetate and lactate was not affected (P > 0.23) by treatments, but feeding MON increased (P = 0.01) propionate during the first 4 days after the challenge. Feeding MON and PAP reduced (P = 0.01) the molar proportion of butyrate. MON was effective in controlling pH and improved ruminal fermentation of acidosis-induced cows. However, PAP was not effective in controlling acidosis. The acidosis induced by the challenge was caused by the accumulation of SCFAs. Therefore, the real conditions for evaluation of this feed additive were not reached in this experiment, since this PAP was proposed to work against lactate-producing bacteria.

Síndrome de Lemierre: um relato de caso e revisão de literatura / Lemierre's syndrome: a case report and literature review

A Síndrome de Lemierre (SL) foi descrita pela primeira vez em 1936 por André Lemierre, em uma publicação com 20 relatos de casos de pacientes com quadro de faringoamigdalite com sintomas graves e mortalidade que chegava a 90%. Apresenta uma prevalência maior em pacientes jovens entre 14 e 24 anos, com apresentação clínica correspondente a quadro de faringoamigdalite que após cerca de sete dias evolui com febre, prostração e dor em região cervical anterior, podendo levar posteriormente a comprometimento pulmonar e de outros órgãos. Neste estudo, trazemos o relato de uma paciente com a síndrome atendida no Hospital Municipal Moysés Deutsch localizado em São Paulo-SP, no ano de 2022. Além disso, foi realizada revisão bibliográfica de sua etiopatogenia, manifestações clínicas e tratamentos, com ênfase em atualizações quanto ao uso da terapia anticoagulante nesta patologia, visto que ainda necessitamos de estudos controlados randomizados em busca de evidências mais consolidadas em relação ao seu uso.

Interação entre Lactobacillus reuteri e bactérias periodontopatogênicas: estudo in vitro e em modelo de invertebrado / Interaction of Lactobacillus reuteri and periodontopathogenic bacteria: an in vitro study and on invertebrate model

A doença periodontal, afecção crônica inflamatória multifatorial, está entre as principais doenças bucais que afetam a população mundial. Entre as bactérias associadas à periodontite, estão Fusobacterium nucleatum e Aggregactibacter actinomycetemcomitans. Novas terapias adjuntas ao tratamento convencional têm sido propostas para a doença periodontal, entre elas o uso de probióticos. Porém, seu uso não está isento de riscos, e uma alternativa para minimizá-los é inativar os microorganismos, mantendo suas propriedades benéficas, o que ocorre com os chamados paraprobióticos. Desse modo, são objetivos deste estudo avaliar os efeitos antimicrobianos de L. reuteri vivo, inativado pelo calor e seus produtos sobre F. nucleatum, A. actinomycetemcomitans e sobre as bactérias comensais, Streptococcus mitis e Streptococcus salivarius, além de estudar os efeitos da interação das preparações e periodontopatógenos em modelo de invertebrado. A atividade antimicrobiana in vitro foi avaliada associando-se as bactérias patogênicas ou comensais a L. reuteri vivo, inativado ou sobrenadante. Após interação, as bactérias foram cultivadas em meio seletivo para contagem de unidades formadoras de colônias (UFC). No estudo em Galleria mellonella, após a infecção com as bactérias patogênicas e as preparações de L. reuteri, foi avaliada a curva de sobrevivência e densidade hemocitária. Os dados foram analisados com o teste estatístico apropriado, ao nível de 5%. Após interação bacteriana in vitro, S. salivarius reduziu o número de UFC de L. reuteri, enquanto que não houve interferência das outras bactérias. O probiótico foi mais eficiente em reduzir o crescimento das bactérias periodontopatogênicas e comensais, exceto para F. nucleatum onde a preparação do sobrenadante foi melhor. In vivo, o sobrenadante foi mais eficiente em aumentar a sobrevivência das lagartas quando infectadas por F. nucleatum. Entretanto, quando infectadas por A. actinomycetemcomitans, nenhuma das preparações aumentou a sobrevivência. Da mesma maneira, nenhuma das preparações aumentaram o número de hemócitos das lagartas após infecção por F. nucleatum e A. actinomycetemcomitans, apesar de todas resultarem em redução na contagem de colônias das bactérias periodontopatogênicas. Dessa forma, concluiu-se que tanto o probiótico quanto os produtos dele derivados apresentaram efeitos antimicrobianos e aumentaram a sobrevivência de G. mellonella quando infectada por F. nucleatum (AU)

Periodontal disease, a chronic multifactorial inflammatory disease, is among the major oral diseases that affects the worldwide population. Among the bacteria associated with periodontitis are Fusobacterium nucleatum and Aggregactibacter actinomycetemcomitans. New therapies have been proposed for periodontal disease as adjunct to conventional treatment, including the use of probiotics. However, their use isn't risk-free and an alternative to that is the inactivation of the microorganisms, maintaining their beneficial properties, which occurs with the paraprobiotics. Thus, the objective of this study is to evaluate the antimicrobial effects of living and heat-killed L. reuteri, and its products on F. nucleatum, A. actinomycetemcomitans and on the commensal bacteria, Streptococcus mitis and Streptococcus salivarius, as well as to study the interaction of the preparations and periodontopathogens in an invertebrate model. In vitro antimicrobial activity was evaluated by associating the pathogenic or commensal bacteria to live, heat killed or L. reuteri supernatant. After interaction, the bacteria were cultured in a selective medium for colony-forming unit (CFU) count. In the study with Galleria mellonella, after infection with pathogenic bacteria and L. reuteri preparations, the survival curve and hemocyte density were evaluated. The data were analyzed with the appropriate statistical test at the 5% level. After bacterial interaction in vitro, S. salivarius reduced the number of CFU of L. reuteri, while there was no interference of the other bacteria. The probiotic was more efficient in reducing the growth of periodontopathogenic and commensal bacteria, except for F. nucleatum. In this case, the supernatant presented better results. In vivo, the supernatant was more efficient in increasing the larvae survival when infected by F. nucleatum. However, when infected by A. actinomycetemcomitans, none of the preparations increased the survival. Likewise, none of the preparations increased the number of hemocytes of the larvae after infection by F. nucleatum and A. actinomycetemcomitans, although all resulted in reduction in the CFU of the periodontopathogenic bacteria. Thus, it was concluded that the probiotic and the products derived therefrom presented antimicrobial effects and increased the survival of G. mellonella when infected by F. nucleatum.(AU)

Effect of curcumin-loaded photoactivatable polymeric nanoparticle on peri-implantitis-related biofilm.

Curcumin has been used as a photosensitizer (PS) for antimicrobial photodynamic chemotherapy (PACT). However, its low solubility, instability, and poor bioavailability challenge its in vivo application. This study aimed to synthesize curcumin-loaded polymeric nanoparticles (curcumin-NP) and determine their antimicrobial and cytotoxic effects. Nanoparticles (NP) were synthesized using polycaprolactone (PCL) as a polymer by the nanoprecipitation method. Curcumin-NP was characterized by particle size, polydispersity index and zeta potential, scanning electron microscopy, and curcumin encapsulation efficiency (EE). Curcumin-NP was compared to free curcumin solubilized in 10% DMSO as photosensitizers for PACT in single and multispecies Porphyromonas gingivalis, Fusobacterium nucleatum, and Streptococcus oralis biofilms. Chlorhexidine 0.12% (CHX) and ultrapure water were used as positive and negative controls. The cytotoxic effect of curcumin-NP was evaluated on human periodontal ligament fibroblast cells (HPLF). Data were analyzed by ANOVA (α=0.05). Curcumin-NP exhibited homogeneity and stability in solution, small particle size, and 67.5% EE of curcumin. Curcumin-NP presented reduced antibiofilm activity at 500 µg/ml, although in planktonic cultures it showed inhibitory and bactericidal effect. Curcumin-NP and curcumin with and without photoactivation were not cytotoxic to HPLF cells. Curcumin-NP has antimicrobial and antibiofilm properties, with better effects when associated with blue light, being a promising therapy for preventing and treating peri-implant diseases.

In vitro assessment of the antimicrobial activity of tetracycline hydrochloride diluted in three different vehicles against Porphyromonas gingivalis, Prevotella intermedia, and Fusobacterium nucleatum.

Background: The development and progression of periodontal diseases is a result of the dynamic interaction of microorganisms within their habitat, and changes in this habitat generate a dysbiotic state. Fusobacterium nucleatum and Prevotella intermedia are bridging microorganisms between the pioneer communities and other microorganisms responsible for periodontitis such as Porphyromonas gingivalis. Tetracycline hydrochloride (TTC-HCl) is commonly used as a coadjutant in periodontal treatment in the form of an antiseptic. However, there are no clear dilution or concentration protocols. Objective: This study aimed to evaluate the in vitro antimicrobial activity of TTC-HCl diluted in sterile water, saline solution, and 2% lidocaine with epinephrine 1:80,000 at concentration of 125, 250, and 500 mg, at three time points- 30, 60, and 120 s - on P. intermedia, F. nucleatum, and P. gingivalis using the Kelsey-Maurer technique. Materials and Methods: The antimicrobial activity of TTC-HCl was evaluated at the proposed concentrations and times, dissolved in the different vehicles at pH 1.9 and 7.0, on F. nucleatum, P. intermedia, and P. gingivalis. The Kelsey-Maurer test was used to verify the presence or absence of colony-forming units. Each test was performed in triplicates with its respective viability controls. Results: Inhibition of F. nucleatum, P. intermedia, and P. gingivalis was achieved with TTC-HCl at all concentrations, dissolved in distilled water, saline solution, and 2% lidocaine with epinephrine 1:80,000 for all times. Conclusions: The results show that TTC-HCl is a good antimicrobial alternative against F. nucleatum, P. intermedia, and P. gingivalis regardless of the vehicle in which it was dissolved, concentration, pH, or time used in this investigation.

Accuracy and Clinical Relevance of Intra-Tumoral Fusobacterium nucleatum Detection in Formalin-Fixed Paraffin-Embedded (FFPE) Tissue by Droplet Digital PCR (ddPCR) in Colorectal Cancer.

The use of droplet digital PCR (ddPCR) to identify and quantify low-abundance targets is a significant advantage for accurately detecting potentially oncogenic bacteria. Fusobacterium nucleatum (Fn) is implicated in colorectal cancer (CRC) tumorigenesis and is becoming an important prognostic biomarker. We evaluated the detection accuracy and clinical relevance of Fn DNA by ddPCR in a molecularly characterized, formalin-fixed, paraffin-embedded (FFPE) CRC cohort previously analyzed by qPCR for Fn levels. Following a ddPCR assay optimization and an analytical evaluation, Fn DNA were measured in 139 CRC FFPE cases. The measures of accuracy for Fn status compared to the prior results generated by qPCR and the association with clinicopathological and molecular patients' features were also evaluated. The ddPCR-based Fn assay was sensitive and specific to positive controls. Fn DNA were detected in 20.1% of cases and further classified as Fn-high and Fn-low/negative, according to the median amount of Fn DNA that were detected in all cases and associated with the patient's worst prognosis. There was a low agreement between the Fn status determined by ddPCR and qPCR (Cohen's Kappa = 0.210). Our findings show that ddPCR can detect and quantify Fn in FFPE tumor tissues and highlights its clinical relevance in Fn detection in a routine CRC setting.

Association of Fusobacterium nucleatum infection and colorectal cancer: A Mexican study.

INTRODUCTION AND AIMS: Colorectal cancer (CRC) is the third most prevalent cancer worldwide. Many risk factors are involved, and current evidence links the gut microbiota and colorectal carcinogenesis. Fusobacterium nucleatum (F. nucleatum) is proposed as one of the risk factors at the onset and during the progression of CRC, due to immune system and inflammatory modulation. MATERIALS AND METHODS: Ninety samples from three different regions of the colon were collected through colonoscopy in patients with CRC, and qPCR TagMan® was conducted to detect F. nucleatum and cytokines (IL-17, IL-23, and IL-10) in tumor, peritumor, and normal samples. The differences between them were analyzed and correlated. RESULTS: The abundance of F. nucleatum determined through the 2-ΔΔCt method in CRC (7.750 [5.790-10.469]) was significantly higher than in the normal control (0.409 [0.251-0.817]) (p < 0.05). There was no significant association between F. nucleatum and the cytokines (p > 0.05). CONCLUSIONS: CRC is a heterogeneous disease that presents and progresses in a complex microenvironment, partially due to gut microbiome imbalance. F. nucleatum was enriched in CRC tissue, but whether that is a cause of the pathology or a consequence, has not yet been clearly defined.

Metagenomics analysis reveals universal signatures of the intestinal microbiota in colorectal cancer, regardless of regional differences

The human gut microbiota is a complex and dynamic community of microorganisms living in our intestines and has emerged as an important factor for colorectal adenocarcinoma (CRC). The purpose of our study was to investigate the microbiota composition in Brazilian CRC patients compared with a local control population (CTL) to find out which changes could be considered universal or regional features in CRC microbiota. Fecal samples were obtained from 28 CRC and 23 CTL individuals. The 16S rRNA gene was used for metagenomic analysis. In addition to the anthropometric variables, the clinical stage (TNM 2018) was considered. Patients with CRC had a significant increase in alpha diversity and a higher percentage of genus Prevotella and a decreased proportion of Megamonas and Ruminococcus. Additionally, the proportion of Faecalibacterium prausnitzii was associated with a better prognosis in the first stages of CRC, and Fusobacterium nucleatum proved to be an important marker of colorectal carcinogenesis and tumor aggressiveness. Although regional differences influence the composition of the microbiota, in the case of CRC, the microhabitat created by the tumor seems to be a major factor. Our results contribute to a better understanding of the carcinogenic process, and even in different environments, some factors appear to be characteristic of the microbiota of patients with CRC.

Evaluating the presence of Mycoplasma hyorhinis, Fusobacterium nucleatum, and Helicobacter pylori in biopsies of patients with gastric cancer.

BACKGROUND: Gastric cancer is the third leading cause of cancer-related deaths worldwide and has been associated with infections that may promote tumour progression. Accordingly, we analysed the presence of Mollicutes, Mycoplasma hyorhinis, Fusobacterium nucleatum and Helicobacter pylori in gastric cancer tissues and evaluated their correlation with clinicopathological factors. METHODS: Using a commercial kit, DNA were extracted from 120 gastric samples embedded in paraffin: 80 from patients with gastric cancer and 40 from cancer free patients, dating from 2006 to 2016. Mollicutes and H. pylori were detected by PCR; F. nucleatum and M. hyorhinis were detected by qPCR, together with immunohistochemistry for the latter bacteria. RESULTS: Mollicutes were detected in the case and control groups (12% and 2.5%) and correlated with the papillary histologic pattern (P = 0.003), likely due to cell transformation promoted by Mollicutes. M. hyorhinis was detected in the case and control group but was not considered a cancer risk factor. H. pylori was detected at higher loads in the case compared to the control group (8% and 22%, P = 0.008) and correlated with metastasis (P = 0.024), lymphatic invasion (P = 0.033), tumour of diffused type (P = 0.028), and histopathological grading G1/G2 (P = 0.008). F. nucleatum was the most abundant bacteria in the case group, but was also detected in the control group (26% and 2.5%). It increased the cancer risk factor (P = 0.045, OR = 10.562, CI95% = 1.057-105.521), and correlated with old age (P = 0.030) and tumour size (P = 0.053). Bacterial abundance was significantly different between groups (P = 0.001). CONCLUSION: Our findings could improve the control and promote our understanding of opportunistic bacteria and their relevance to malignant phenotypes.

Nivel de higiene y prevalencia de Porphyromona gingivalis y Fusobacterium nucleatum en pacientes recuperados de SARS-CoV-2 / Hygiene level and prevalence of Porphyromona gingivalis and Fusobacterium nucleatum in recovered SARS-CoV-2 patients

Introducción: El SARS-CoV-2 afecta el sistema respiratorio en diferentes grados. La cavidad oral es el lugar más colonizado por bacterias, por lo tanto, al no tener una adecuada higiene pueden presentarse diferentes enfermedades secundarias, lo que ha causado alerta en el gremio odontológico, ya que puede contribuir a complicaciones posteriores en los pacientes. Material y métodos: El estudio fue conformado por 47 pacientes voluntarios recuperados de SARS-CoV-2, residentes de Montemorelos, Nuevo León, México, donde fueron atendidos en Bucalia Dent, consultorio dental. Después del consentimiento informado de cada paciente, se realizó una historia clínica para conocer los síntomas, enfermedades sistémicas, ausencia de dientes y nivel de inflamación gingival de acuerdo al índice de Loe y Silness. A continuación, se tomó una muestra de biofilm microbiano (placa dentobacteriana), la cual se suspendió en una solución buffer de fosfato, posteriormente fue llevada al Centro de Investigación y Desarrollo en Ciencias de la Salud (CIDICS), Monterrey, N.L, México. Se extrajo DNA y se purificó, después se realizó PCR para detectar los patógenos orales; la PCR se visualizó en gel de agarosa (1.5%) por tinción de bromuro de etidio. Resultados: Se detectó 80.85% Porphyromona gingivalis y 68.09% Fusobacterium nucleatum en pacientes recuperados de SARS-CoV-2; 23.4% presentaron inflamación leve de acuerdo al índice de Loe y Silness, 54.5% fueron masculinos y 45.5% femeninos. Por otro lado, 36.4% de los pacientes con inflamación leve tenían de cuatro a seis dientes ausentes. En estos pacientes se detectó 18.18% únicamente con Fusobacterium nucleatum y 27.27% sólo con Porphyromona gingivalis; el sexo masculino tuvo predisposición en 66.6% y el femenino en 33.33%. Se observó infección con los dos patógenos presentes en 45.45%; y 60% de estos pacientes fueron masculinos. Conclusiones: Los pacientes recuperados de SARSCoV- 2 analizados en esta investigación mostraron mala higiene oral y alta prevalencia de los patógenos mencionados altamente relacionados a inflamación gingival o enfermedad periodontal, lo que nos indica que es indispensable la intervención del odontólogo al finalizar el periodo de infección de cada paciente (AU)

Introduction: SARS-CoV-2 affects the respiratory system to different degrees. The oral cavity is a colonized place by bacterias, therefore, by not having good hygiene, different secondary diseases can occur; this has caused an alert in the dental industry, since it can contribute to later complications in patients. Material and methods: The study was conducted in 47 SARS-CoV-2 recovered volunteers from the Montemorelos city of the Nuevo León state, Mexico, who were attended at the Bucalia Dent dental clinic. An informed consent was obtained from each of the patients, then their clinical history was documented in order to know the symptoms, previous systemic diseases, absence of teeth and degree of gingival inflammation, as suggested by Loe and Silness. Subsequently, a dental plaque sample was taken from all patients, which was suspended in a phosphate buffered solution and shipped to The Center for Research and Development in Health Sciences (CIDICS), Monterrey, NL, Mexico for storage. DNA extraction and purification was performed and PCR was carried out for the oral pathogens detection. All PCR products were visualized on 1.5% agarose gel by ethidium bromide staining. Results: Porphyromona gingivalis and Fusobacterium nucleatum were detected in 80.85% and 68.09% of SARS-CoV-2 recovered patients, respectively. 23.4% showed mild inflammation based on the Loe and Silness criteria, 54.5% were male and 45.5% female. On the other hand, 36.4% of patients with mild inflammation had between 4 to 6 missing teeth. A single infection by Fusobacterium nucleatum was detected in 18.18% and by Porphyromona gingivalis in 27.27%; the male sex had a predisposition with 66.66% and 33.33% female; coinfection of both pathogens was observed in 45.45% where 60% were male. Conclusions: SARS-CoV-2 recovered patients show poor oral hygiene and a high prevalence of oral pathogens related to the development of inflammatory gingival or periodontal disease, this suggests the need for an odontological clinical intervention at the end of the course of infection or disease caused by SARS-CoV-2 (AU)

Anaerobio osteomyelitis. A rare condition in children / Osteomielitis por anaerobios. Una entidad poco frecuente en pediatría

ABSTRACT Osteoarticular infections due to anaerobes are very rare in children, with the Fusobacterium genus being the most frequently isolated. The course is usually subacute and, although there are predisposing factors described, most patients do not present with them. Generally, joint fluid cultures are sterile since these microorganisms are very sensitive to contact with oxygen, so they require specific culture media. All of the above causes the diagnosis to be delayed, increasing the risk of long-term sequelae. However, the prognosis improves when treatment is started early. The case is presented of a 10-year-old patient who was admitted for 30 days due septic arthritis of the right hip caused by Fusobacterium nucleatum During the admission, he required three surgical interventions, and completed 6 weeks of effective antibiotic therapy, with a good outcome and remaining asymptomatic at the current time.

RESUMEN Las infecciones osteoarticulares por anaerobios son muy raras en los niños, siendo el género Fusobacterium el que se aisla con más frecuencia. El curso suele ser subagudo y, aunque hay factores predisponentes descritos, la mayoría de los pacientes no los presenta. Generalmente, los cultivos de liquido articular son estériles ya que estos microorganismos son muy sensibles al contacto con el oxigeno, por lo que precisan medios de cultivo específicos. Todo lo anterior hace que el diagnóstico se retrase y que el riesgo de secuelas a largo plazo aumente. Sin embargo, el pronóstico mejora cuando el tratamiento se inicia de modo precoz. Por todo ello, presentamos el caso de un paciente de 10 anos con una artritis séptica de cadera derecha por Fusobacterium nucleatum que permaneció ingresado 30 dias. Durante el ingreso precisó 3 intervenciones quirúrgicas y cumplió 6 semanas de antibioterapia efectiva, con buena evolución; permanece asintomático en el momento actual.

Differential involvement of the canonical and noncanonical inflammasomes in the immune response against infection by the periodontal bacteria Porphyromonas gingivalis and Fusobacterium nucleatum.

We examined the involvement of the P2 × 7 receptor and the canonical and noncanonical inflammasomes in the control of single-species or dual-species infection by the periodontal bacteria Porphyromonas gingivalis and Fusobacterium nucleatum in cells and mice. Stimulation of the P2 × 7 receptor leads to activation of the canonical NLRP3 inflammasome and activation of caspase-1, which leads to cleavage of pro-IL-1ß to IL-1ß, a key cytokine in the host inflammatory response in periodontal disease. The non-canonical inflammasome pathway involves caspase-11. Thus, wildtype (WT), P2 × 7-/-, caspase-11-/- and caspase-1/11-/- mice were co-infected with both bacterial species. In parallel, bone marrow-derived macrophages (BMDMs) from WT mice and the different knockout mice were infected with P. gingivalis and/or F. nucleatum, and treated or not with extracellular ATP, which is recognized by P2 × 7. F. nucleatum infection alone promoted secretion of IL-1ß in BMDMs. Conversely, the canonical pathway involving P2 × 7 and caspase-1 was necessary for secretion of IL-1ß in BMDMs infected with P. gingivalis and in the mandible of mice coinfected with P. gingivalis and F. nucleatum. The P2 × 7 pathway can limit bacterial load in single-species and dual-species infection with P. gingivalis and F. nucleatum in BMDMs and in mice. The non-canonical pathway involving caspase-11 was required for secretion of IL-1ß induced by F. nucleatum infection in BMDMs, without treatment with ATP. Caspase-11 was also required for induction of cell death during infection with F. nucleatum and contributed to limiting bacterial load during F. nucleatum infection in BMDMs and in the gingival tissue of mice coinfected with P. gingivalis and F. nucleatum. Together, these data suggest that the P2 × 7-caspase-1 and caspase-11 pathways are involved in the immune response against infection by P. gingivalis and F. nucleatum, respectively.

Association of Fusobacterium nucleatum infection and colorectal cancer: A Mexican study. / Asociación entre infección por Fusobacterium nucleatum y cáncer colorrectal: un estudio mexicano.

INTRODUCTION AND AIMS: Colorectal cancer (CRC) is the third most prevalent cancer worldwide. Many risk factors are involved, and current evidence links the gut microbiota and colorectal carcinogenesis. Fusobacterium nucleatum is proposed as one of the risk factors at the onset and during the progression of CRC, due to immune system and inflammatory modulation. MATERIALS AND METHODS: Ninety samples from three different regions of the colon were collected through colonoscopy in patients with CRC, and qPCR TagMan® was conducted to detect F. nucleatum and cytokines (IL-17, IL-23, and IL-10) in tumor, peritumor, and normal samples. The differences between them were analyzed and correlated. RESULTS: The abundance of F. nucleatum determined through the 2-ΔΔCt method in CRC (7.750 [5.790-10.469]) was significantly higher than in the normal control (0.409 [0.251-0.817]) (p<0.05). There was no significant association between F. nucleatum and the cytokines (p>0.05). CONCLUSIONS: CRC is a heterogeneous disease that presents and progresses in a complex microenvironment, partially due to gut microbiome imbalance. F. nucleatum was enriched in CRC tissue, but whether that is a cause of the pathology or a consequence, has not yet been clearly defined.

Identification of Fusobacterium nucleatum in primary and secondary endodontic infections and its association with clinical features by using two different methods.

OBJECTIVE: Fusobacterium nucleatum is an important oral pathogen involved in endodontic infections. This study aimed to assess the frequency of Fusobacterium nucleatum in primary and secondary endodontic infections and its associations with the clinical features in a Brazilian population by using both culture and nested PCR methods. METHODS: A total of 100 microbial samples from patients with primary (n=50) and secondary endodontic infections (n=50) were analyzed by using culture and nested PCR methods. Strict anaerobic techniques were used for culture and identification of F. nucleatum. The DNA extracted from the samples was analyzed for the presence of target species by using species-specific primers. RESULTS: Culture and nested PCR methods detected F. nucleatum, respectively, in 11/100 and 82/100 root canals. F. nucleatum was isolated by culture from 10/50 (20%) root canals with primary infections and from 1/50 (2%) root canal with secondary/persistent infections. Nested PCR detected F. nucleatum in 42/50 (84%) root canals with primary infections and in 40/50 (80%) root canals with secondary/persistent endodontic infections. F. nucleatum was associated with spontaneous pain, tenderness to percussion, pain on palpation, swelling, tooth mobility, wet root canals, hemorrhagic exudate, tooth decay, inadequate restoration, and poor endodontic filling. CONCLUSION: F. nucleatum was found in more cases of primary endodontic infections than in cases of secondary/persistent ones. A higher prevalence of F. nucleatum was detected by using the nested PCR method than by using culture. The presence of F. nucleatum in the root canals was associated with several clinical features. CLINICAL RELEVANCE: The high prevalence of F. nucleatum in the root canals detected by molecular methods, and its association with several clinical features reveals the importance of these species in the development of apical pathologies and reinforces the need of an endodontic treatment directed to bacterial elimination.

The Role of Fusobacterium nucleatum in Colorectal Carcinogenesis.

Colorectal cancer (CRC) is one of the most frequent and deadly neoplasms worldwide. Genetic factors, lifestyle habits, and inflammation are important risk factors associated with CRC development. In recent years, growing evidence has supporting the significant role of the intestinal microbiome in CRC carcinogenesis. Disturbances in the healthy microbial balance, known as dysbiosis, are frequently observed in these patients. Pathogenic microorganisms that induce intestinal dysbiosis have become an important target to determine the role of bacterial infection in tumorigenesis. Interestingly, the presence of different bacterial strains, such as Fusobacterium nucleatum, has been detected in tissue and stool from patients with CRC and associated with substantial clinical and molecular features, as well as with patient therapy response. Therefore, understanding how the presence and levels of F. nucleatumstrains in the gut affect the risk of CRC onset and progression may inform suitable candidates for interventions focused on modulation of this bacteria. Here we review new insights into the role of gut microbiota in CRC carcinogenesis and the clinical utility of using the detection of F. nucleatum in different settings such as screening, prognosis, and microbiota modulation as a means to prevent cancer, augment therapies, and reduce adverse effects of treatment.