Changes In Bacterial Flora Research Articles

Normal Bacterial Flora of The Oral Cavity

The oral cavity is a biopolitical environment, very similar to the gastrointestinal microenvironment, which hosts billions of microorganisms known collectively as oral microbiota. These bacteria were shown to have important functions within the host oral ecosystem as they inhibit the attachment of pathogenic microorganisms and actively participate in the immune reaction of the host. Gingival crevices harbor various types of bacteria and are typically part of a balance; any disparity could result in oral disease such as dental caries, periodontal diseases, even systemic infections. This article systematically summarises the regular bacterial microbiota in the oral cavity, a description of its functions, and the aspects which precipitate the changes in bacterial flora

Changes in bacterial flora and flavor of shrimp paste under different salt concentrations

In this paper, Antarctic krill was used as the raw material. Physicochemical indexes, flora changes and flavor substances of shrimp paste with different salt concentrations and fermentation days were investigated. The main dominant bacterial groups in the shrimp paste samples were detected by 16S rDNA high-throughput sequencing technology. At phylum level, the dominant bacteria groups were Proteobacteria, Firmicutes and Actinobacteria, while at genus level, the dominant bacteria groups were Staphylococcus, Psychrobacter and Herbaspirillum. Qualitative analysis of volatile compounds in shrimp paste samples by GC-IMS technique. A total of 29 volatiles were detected, and a total of 37 volatile flavor compounds including dimers and trimers were isolated and identified, including 16 aldehydes, 8 alcohols, 8 ketones, 2 ethers and 3 esters. Establishing correlations between important colonies and volatile compounds.

Differential impact of environmental factors on airborne live bacteria and inorganic particles in an underground walkway.

We previously reported that variations in the number and type of bacteria found in public spaces are influenced by environmental factors. However, based on field survey data alone, whether the dynamics of bacteria in the air change as a result of a single environmental factor or multiple factors working together remains unclear. To address this, mathematical modeling may be applied. We therefore conducted a reanalysis of the previously acquired data using principal component analysis (PCA) in conjunction with a generalized linear model (Glm2) and a statistical analysis of variance (ANOVA) test employing the χ2 distribution. The data used for the analysis were reused from a previous public environmental survey conducted at 8:00-20:00 on May 2, June 1, and July 5, 2016 (regular sampling) and at 5:50-7:50 and 20:15-24:15 on July 17, 2017 (baseline sampling) in the Sapporo underground walking space, a 520-meter-long underground walkway. The dataset consisted of 60 samples (22 samples for "bacterial flora"), including variables such as "temperature (T)," "humidity (H)," "atmospheric pressure (A)," "traffic pedestrians (TP)," "number of inorganic particles (Δ5: 1-5 μm)," "number of live airborne bacteria," and "bacterial flora." Our PCA with these environmental factors (T, H, A, and TP) revealed that the 60 samples could be categorized into four groups (G1 to G4), primarily based on variations in PC1 [Loadings: T(-0.62), H(-0.647), TP(0.399), A(0.196)] and PC2 [Loadings: A(-0.825), TP(0.501), H(0.209), T(-0.155)]. Notably, the number of inorganic particles significantly increased from G4 to G1, but the count of live bacteria was highest in G2, with no other clear pattern. Further analysis with Glm2 indicated that changes in inorganic particles could largely be explained by two variables (H/TP), while live bacteria levels were influenced by all explanatory variables (TP/A/H/T). ANOVA tests confirmed that inorganic particles and live bacteria were influenced by different factors. Moreover, there were minimal changes in bacterial flora observed among the groups (G1-G4). In conclusion, our findings suggest that the dynamics of live bacteria in the underground walkway differ from those of inorganic particles and are regulated in a complex manner by multiple environmental factors. This discovery may contribute to improving public health in urban settings.

Effects of antimicrobial nanocomposite films packaging on the postharvest quality and spoilage bacterial communities of mushrooms (Chanterelles)

Poly (lactic acid) (PLA) composite films with the addition of mesoporous silica nanoparticles MSN (0, 2, 4 and 6 wt%) loaded with 10 wt% citral (CIT) were prepared for application in Chanterelles packaging. Composite films with added MSN/CIT showed good mechanical properties, especially 4MSN/CIT/PLA. Changes in physicochemical properties and bacterial flora of Chanterelles during packaging and storage were tested. Compared with CIT/PLA, Chanterelles packed with 4MSN/CIT/PLA showed about 1.62-times lower browning value, 1.53-times lower electrolyte permeability, and 1.83- and 1.78-times lower PPO and POD, respectively, at 12 day. Better physicochemical properties of Chanterelles can be maintained. For bacterial flora changes, Chanterelles packaged with 4MSN/CIT/PLA had more stable flora (p < 0.05) and lower species diversity during storage (p < 0.05), effectively controlling the growth and reproduction of their dominant spoilage bacteria (Enterobacteriaceae spp). In conclusion, the composite membranes obtained by the addition of MSN/CIT to PLA have great potential in the storage of Chanterelles.

Bacterial Population Changes during the Degradation Process of a Lactate (LA)-Enriched Biodegradable Polymer in River Water: LA-Cluster Preferable Bacterial Consortium.

The lactate-based polyester poly[lactate (LA)-co-3-hydroxybutyrate (3HB)], termed LAHB, is a highly transparent and flexible bio-based polymeric material. There are many unknowns regarding its degradation process in riverine environments, especially the changes in bacterial flora that might result from its degradation and the identities of any LAHB-degrading bacteria. LAHB were immersed in the river water samples (A and B), and LAHB degradation was observed in terms of the weight change of the polymer and the microscopic changes on the polymer surfaces. A metagenomic analysis of microorganisms was conducted to determine the effect of LAHB degradation on the aquatic environment. The bacterial flora obtained from beta diversity analysis differed between the two river samples. The river A water sample showed the simultaneous degradation of LA and 3HB even though the copolymer was LA-enriched, suggesting preferable hydrolysis of the LA-enriched segments. In contrast, only 3HB degraded for the LAHB in the river B water sample. The linear discriminant analysis effect size (LEfSe) analysis revealed 14 bacteria that were significantly increased in the river A water sample during LAHB degradation, suggesting that these bacteria preferentially degraded and assimilated LA-clustering polymers. Our metagenomic analysis provides useful insights into the dynamic changes in microbial communities and LA-clustering polymer-degrading bacteria.

Traditional microbial control methods used in sake brewing effectively suppress predominant bacteria emerging during production of rice koji

Rice koji is a raw material used in the production of sake; however, details regarding the microbial flora and their dynamics in rice koji during the production process are poorly understood. Clarifying these issues can contribute to proposing a method and evaluation that will improve the quality of rice koji and sake. The aim of this study was to determine the microflora in rice koji and the effectiveness of the traditional microbial control techniques used in the sake production process. We analyzed the diversity and changes in bacterial flora during rice koji production by amplicon sequencing of the 16S rRNA gene. The predominant taxon in all rice koji samples was family Staphylococcaceae. The microbial population and the changes in its distribution for five consecutive stages in rice koji production were examined by direct colony counting. Bacteria counts in all samples were below the limit of detection initially, then increased rapidly toward the final stage. The predominant bacterial colonies from all samples were yellow and were identified as Staphylococcus gallinarum through 16S rRNA gene sequence similarity. The S. gallinarum isolates exhibited faster growth in pregelatinized rice medium. Interestingly, the growth of S. gallinarum isolates was suppressed by low temperature (12 °C), ethanol concentration (≥6%) and the addition of lactic acid, which are traditional microbial control methods used during sake fermentation. Therefore, proper control of the traditional sake production process can effectively inhibit the growth of undesirable bacteria such as S. gallinarum that emerge during the production of rice koji.

An Observational Study on Changes in the Oral and Gut Microbiota through Professional Mechanical Tooth Cleaning, including Tooth-Brushing Instructions in Patients with Multi-Bracket Appliances

Multi-bracket appliances have long been established as tools for treating malocclusions. However, the complex construction and difficulty in cleaning due to their long-term intraoral retention have hindered the prevention of caries and periodontitis. In this study, professional mechanical tooth cleaning (PMTC), including tooth-brushing instructions, was continuously performed for 3 months in 24 patients who had worn multi-bracket appliances for more than 6 months, and changes in the oral and gut microbiota were examined using one-way repeated-measures analysis of variance. Additionally, changes in bacterial flora associated with different treatment durations were verified using the Pearson correlation coefficient. The results showed that continuous PMTC significantly reduced the amount of plaque in the oral cavity. No significant changes were observed in the oral or gut microbiota and no significant increase in pathogenic bacteria was observed. Therefore, our results suggest that continuous PMTC during orthodontic treatment with multi-brackets may inhibit the growth of pathogenic bacteria by maintaining a clean oral environment and avoiding dysbiosis in both the oral and gut microbiota. Significant changes in the gut microbiota with different treatment durations suggested that differences in food intake and food choices at each treatment stage of orthodontic treatment may affect the gut microbiota.

Changes In Bacterial Flora Of Burn Wounds And Their Antibiotic Susceptibility Patterns At A Tertiary Hospital In Ghana

Objective: To determine the time-related changes in burn wound bacteria and to determine the antibiotic susceptibilities of these bacteria. Methodology: The study was carried out over a 4-month period from September 2017 at the Burns Unit of the Korle-Bu Teaching Hospital in Accra. Wound swabs were taken weekly from burn patients on admission and each patient was followed-up for a month. The swabs were cultured, and antibiotic susceptibility testing done on isolated pathogens. Results: A total of 214 wound swabs were taken from 59 patients enrolled with an overall isolation rate of 65%. Gram negative isolates predominated each week throughout the period of monitoring. The commonest bacterial isolate was P. aeruginosa which formed 51.8% of all isolates, followed by coagulase negative staphylococci 13.7%, S. aureus 10.1% and other Gram-negative bacilli. Sixty-four percent of S. aureus were resistant to cefoxitin (MRSA), and100% resistant to penicillin. Resistance to the cephalosporins and fluroquinolones was generally high among the Gram-negative bacteria. P. aeruginosa had moderate resistance to the anti-pseudomonal antibiotics. Resistance to amikacin among the Gram-negative bacteria was low. Conclusion: Burn wounds are colonized by pathogenic bacteria, some highly antibiotic-resistant. There were no significant time-related changes in bacterial flora of burn wounds.

Microbiota-accessible carbohydrates (MACs) as novel gut microbiome modulators in noncommunicable diseases

The gut microbiota has a significant role in human health and is affected by many factors. Diet and dietary components have profound impacts on the composition of the gut microbiome and largely contribute to the change in bacterial flora. A high-fiber diet increased dietary fiber (DF) fermentation and the production of short-chain fatty acids (SCFAs), which increased the number of microorganisms. Microbiota-accessible carbohydrates (MACs), a subgroup of fermentable carbohydrates such as DF, are defined as indigestible carbohydrates metabolized by microbes. These carbohydrates are important components to sustain the microbial environment of the complicated digestive tract and avoid intestinal dysbiosis. Each MAC has a unique property and can therefore be used as a sensitive output microbiota modulator to support host homeostasis and modulate health. In addition to the overall health-developing effects, MACs are thought to have a promising effect on the prevention of non-communicable diseases (NCDs), which are major health problems worldwide. The aim of the manuscript was to describe microbiota-accessible carbohydrates and summarize their effects on gut modulation and NCDs.

Caffeic acid-grafted chitosan/polylactic acid packaging affects bacterial infestation and volatile flavor of postharvest Agaricus bisporus

To clarify the effect of caffeic acid-grafted-chitosan/polylactic acid (CA-g-CS/PLA) packaging on the bacterial infestation and volatile flavor of postharvest Agaricus bisporus, electronic nose (E-nose) combined with gas chromatography-mass spectrometry (GC–MS) analysis was utilized to detect the volatile flavor. 16s rDNA sequencing technology was used to determine the species and changes of bacterial flora on the surface of Agaricus bisporus. The correlation between volatile flavor substances and bacterial communities was analyzed. The results showed that compared with polyethylene (PE) packaging, CA-g-CS/PLA packaging significantly delayed the loss of characteristic volatiles such as 1-octene-3-ol, 3-octanol, 3-octone and the ability to inhibit the growth of total bacteria count (TBC) was elevated by 12.6 % at 15 d of storage. Moreover, CA-g-CS/PLA packaging significantly reduced the abundance of spoilage bacteria such as Flavobacterium, Pedobacter and Pseudomonas compared to PE packaging and the sum of the three fell from 38 % to around 8 %. The correlation analysis showed that spoilage bacteria were significantly negatively correlated with 1-octene-3-ol and 3-octone and significantly positively correlated with spoil flavors such as benzaldehyde, indole and naphthalene. These results indicated that CA-g-CS/PLA packaging could delay the deterioration of the postharvest volatile flavor of Agaricus bisporus by inhibiting the abundance of specific spoilage bacteria.

Conjunctival sac microbiome in anophthalmic patients: Flora diversity and the impact of ocular prosthesis materials.

To explore the changes of bacterial flora in anophthalmic patients wearing ocular prosthesis (OP) and the microbiome diversity in conditions of different OP materials. A cross-sectional clinical study was conducted, involving 19 OP patients and 23 healthy subjects. Samples were collected from the upper, lower palpebral, caruncle, and fornix conjunctiva. 16S rRNA sequencing was applied to identify the bacterial flora in the samples. The eye comfort of each OP patient was determined by a questionnaire. In addition, demographics information of each participant was also collected. The diversity and richness of ocular flora in OP patients were significantly higher than that in healthy subjects. The results of flora species analysis also indicated that in OP patients, pathogenic microorganisms such as Escherichia Shigella and Fusobacterium increased significantly, while the resident flora of Lactobacillus and Lactococcus decreased significantly. Within the self-comparison of OP patients, compared with Polymethyl Methacrylate (PMMA), prosthetic material of glass will lead to the increased colonization of opportunistic pathogens such as Alcaligenes, Dermabacter and Spirochaetes, while gender and age have no significant impact on ocular flora. The ocular flora of OP patients was significantly different from that of healthy people. Abundant colonization of pathogenic microorganisms may have an important potential relationship with eye discomfort and eye diseases of OP patients. PMMA, as an artificial eye material, demonstrated potential advantages in reducing the colonization of opportunistic pathogens.

Spatial transcriptomes and microbiota reveal immune mechanism that respond to pathogen infection in the posterior intestine of Sebastes schlegelii.

The intestine is a site of immune cell priming at birth. Therefore, spatial transcriptomes were performed to define how the transcriptomic landscape was spatially organized in the posterior intestine of Sebastes schlegelii following Edwardsiella piscicida infection. In the healthy condition, we identified a previously unappreciated molecular regionalization of the posterior intestine. Following bacterial infection, most immune-related genes were identified in mucosa layer. Moreover, investigation of immune-related genes and genes in immune-related KEGG pathways based on spatial transcriptomes shed light on which sections of these genes are in the posterior intestine. Meanwhile, the high expression of genes related to regeneration also indicated that the posterior intestine was responding to the invasion of pathogens by constantly proliferating new cells. In addition, the increasing microbiota communities indicated that these bacteria maintained posterior intestine integrity and shaped the mucosal immune system. Taken together, spatial transcriptomes and microbiota compositions have significant implications for understanding the immune mechanism that responds to E. piscicida infection in the posterior intestine of S. schlegelii, which also provides a theoretical basis for the spatial distribution of immune genes and changes in bacterial flora in other teleosts in the process of resisting pathogens.

Variations in bacterial spectrum and physicochemistry of top soils exposed to gas flaring in Ologbo community, Edo state

Nigeria is a major exporter of petroleum and natural gas and a majority of the petroleum exploratory activities takes place in the Niger Delta area, where high rates of gas flaring associated with exploration and production of these products occur. The study investigated changes in bacterial flora and physicochemistry of soils within the Oredo flow station facility. Seven soil samples were collected in triplicates at radial distances of 40m, 80m, 120m, 160m, 200m, 1km from the flare stack and the control sample was collected from a farmland far from the flow-station but within the community. Standard methods were employed in evaluating the physicochemical parameters and bacteriological analysis was conducted using serial dilution and pour plate methods. The results revealed that gas flaring had significant effects on some soil physicochemical parameters. The impact of gas flare was found to lower the moisture content at 4.44 % for soils collected at 40m whilst for the control soil, it was 12.83%. The nitrate and total nitrogen content of the soil varied from 9.96±1.44 to 12.21±0.13mg/kg and 0.01±0.00 to 0.2±0.01%. The total heterotrophic bacteria count varied from 0.4 ± 0.33 to 14.67±3.77 ×106 cfu/g. Identified bacterial species were; Streptococci sp., Corynebacterium sp., Stenotrophomonas sp., Staphylococcus sp., Micrococcus sp., Bacillus sp., Acinetobacter sp., Burkholderia sp. and Bacillus sp. The results revealed that gas flaring had a negative effect on soil bacteria population and physicochemical properties.

Occlusal Trauma has a Primary Role in the Etiology of Site-Specific Periodontitis/ Perimplantitis

An in media preponderant school of thought considers the onset from the very beginning of the periodontal/periimplant disease due to an infection. In other words the disease begins when pathogenic bacteria infect a tissue which is wholly healthy thanks to saprophyte bacteria. We will consider occlusal trauma as well as cause of the disease. The aim of the work is to demonstrate how the long-lasting mechanical stress over gingival-tooth/implant apparatus can induce the change of bacterial flora from saprophyte to opportunistic pathogenic one capable of causing periodontal/perimplant infection. Two cases are presented referring to two different patients, one affected by periodontitis, the other by perimplantitis, in which periodontitis/perimplantitis occurred only on a single tooth/implant, both in evident occlusal trauma, sparing all contiguous elements. Since periodontal/perimplant disease is a multifactorial syndrome with hypothetical causes from infectious to genetic ones, or related to internal medicine and biomechanics,this research proposes to understand the causes of the periodontal/perimplant disease moving away from conventional schemas based on the insufficient hygiene with consequent build-up of dental plaque which is considered “the only “cause of the disease. In fact we must consider both teeth and implants not as static elements but as a dynamic complex which during its function can undergo a very heavy load according to precise biological laws. In addition to all the best-known risk factors the causes that displace mandible and therefore modify occlusion must deserve specific attention. Considerable overloading on teeth and/or implants involved can contribute to the pathogenesis of the tooth/implant and its supporting tissue too. The two clinical cases of the work present site-specific periodontitis and perimplantitis. Both cases show that occlusal trauma with its consequent chronic mechanical stress is the initial cause of the disease. Later the subsequent inflamed tissue becomes an easy road to the periodontal-perimplant infection as final stage. Following the evolution of the two cases it becomes apparent that it is important to know the diseases due to occlusal trauma. Only through that knowledge we can prevent the diseases described above.

Primary Adenocarcinoma at Ileostomy—A Rare Late Complication: Three Cases and Literature Review

Introduction Primary adenocarcinoma at the ileostomy site is a rare complication, with only 57 cases reported in the literature. The primary diagnosis is usually ulcerative colitis (UC) or familial adenomatous polyposis (FAP). Cases We present 3 cases of adenocarcinoma at the ileostomy site. Two of our 3 cases have a previous diagnosis of cancer, with no previous diagnosis of UC or FAP. Discussion Adenocarcinoma at ileostomy is a rare late complication of permanent ileostomy. Possible etiologies are chronic irritation and changes in bacterial flora that lead to metaplasia and cancer development. Conclusion Adenocarcinoma at the ileostomy site is a rare complication with good prognosis if detected early. Diagnosis is by biopsy, and treatment is surgical. A biopsy should be considered in any abnormal growth around the ileostomy.

Research on pharyngeal bacterial flora in transoral atlantoaxial operation and the postoperative follow-up study

ObjectivesTo study the changes of bacterial flora after a series of preoperative oral disinfection and the postoperative recovery of nerve function of patients with craniovertebral junction disorders who were treated with transoral approach operations.MethodsThis research analyzed 20 cases collected from October 2009 to May 2010. All these patients were with CVJ disorders, including 8 males and 12 females, aged 2 to 66 (38.1 on average), and they were all treated with transoral approach operations. The mucosa samples of the posterior pharyngeal wall were sent for bacteria culture. These samples were collected by sterile cotton swabs at four crucial points, including 3 days before operation/before gargling, 3 days after continuous gargling/after anesthesia intubation on the day of operation, after intraoperative cleaning and washing of the mouth, and after intraoperative iodophor immersion. The microflora was stained by means of smear and further counted after an investigation by microscope. The neural function of patients was evaluated by the ASIA classification and the JOA scores. All patients but two with posterior stabilization performed respectively underwent transoral atlantoaxial reduction plate (TARP) fixation consecutively in the same sitting. A regular reexamination of cervical vertebra with lateral and open mouth X-ray, CT and MRI was conducted after operation to evaluate the reduction of atlantoaxial dislocation, internal fixation position, bone graft fusion, inflammatory lesions and tumor recurrence.ResultsThis bacteriological research showed that the mucosa of the posterior pharyngeal wall of all the patients was in a sterile state after a series of oral preoperative preparations and intraoperative iodophor disinfection, which was considered as type I incision. The bacterial culture results of the mucosa samples of the posterior pharyngeal wall collected at different time points showed significant differences (χ2 = 42.762, P = 0.000). All the patients had improvement in ASIA, and their neural functions were improved to different levels after operation. There was a significant difference in JOA scores before and after operation (t = 8.677, P = 0.000). Postoperative imaging examination showed that the atlantoaxial screw position was good and firm, and the CVJ disorders were treated appropriately.ConclusionIt is safe and effective to cut the posterior pharyngeal muscle layer and implant internal fixation by means of transoral approach.

Very early endoscopic DCR in acute suppurative dacryocystitis perspective

Acute dacryocystitis is not uncommon in oculofacial and general ophthalmology clinics admissions. It happens with sudden inflammation of lacrimal sac that frequently occurs in the setting of pre-existing nasolacrimal duct obstruction. Long standing tear flow stasis results in change of bacterial flora and bacterial over-growth in the lacrimal sac as a reservoir of stagnant tear., However, acute dacryocystitis can be associated with dacryoliths or indefinite pre-existing anatomic nasolacrimal duct obstruction.

Immunological and Enzymatic study of Staphylococcus aureus Bacteria and fungi isolated from oral cavity

The current work aimed to study the propagation of Staphylococcus aureus and Candida sp. and. in oral cavity of the human, and their effective on innetimmune response and to describe the biochemical &amp;kinetic properties of PLB from the Staphylococcus aureus. and asporogenous yeast C. tropicalis. The study included 25 patients, ages (12-65) years, with periodontal diseases and at least two sites with probing depth ≥ 3 mm. Participants' data were assessed individually. A sample is taken from the oral cavity (mucous membrane, tongue and cheek) with a sterile swab. Among all the patients studied, (16) 64% showed Staphylococcus in the oral cavity while Streptococcus sp (3) 12% showed candidiasis in the oral cavity and (5) 20 % of other bacteria(1) 4% in the oral cavity. The effect of microbial inflammation on the multidirectional secretion of interleukin (IL) -10, IL-6 has been studied in patients with oral cavity infections. Samples and wash swabs were taken from 25 healthy patients and 25 patients. The supernatant fractions of IL-6 and IL-10 were examined by commercial ELISAs. Analysis of interleukin levels in the two groups with the Mann-Whitney test.IL-6 levels various significantly between the patients, the control group, and the control groups. Median levels of IL-10 in both groups were uniformly low but the mean levels were not statistically different. The observed change in bacterial flora that is characteristic of stomatitis does not enhance or suppress oral levels of IL-6 and IL-10. Staphylococcus aureus, and Candida tropicalis have been isolated oral cavity and under the periodontal sinuses infection. It was filtered 2.5 fold at40 ºC from a culture broth and has an estimated molecular mass of 50kDa.The enzyme was two pH targets, one acid (pH 4.0) and other alkaline (pH 7.5). At acidic pH the enzyme showed a higher affinity for all tested phospholipids without metal ions while its affinity affected by the presence of metal ions at alkaline conditions and the enzyme activity inhibited by Fe3+ and Hg2+.

Novel antibody assessment method for microbial compositional alteration in the oral cavity

Recently, it has been demonstrated that dysbiosis, an alteration in commensal microflora composition, is intimately involved in the onset of a variety of diseases. It is becoming increasingly evident that the composition of commensal microflora in the oral cavity is closely connected to oral diseases, such as periodontal disease, and systemic diseases, such as inflammatory bowel disease. Next-generation sequencing techniques are used as a method to examine changes in bacterial flora, but additional analytical methods to assess bacterial flora are needed to understand bacterial activity in more detail. In addition, the oral environment is unique because of the role of secretory antibodies contained in saliva in the formation of bacterial flora. The present study aimed to develop a new method for evaluating the compositional change of microbiota using flow cytometry (FCM) with specific antibodies against the bacterial surface antigen, as well as salivary antibodies. Using specific antibodies against Streptococcus mutans, a causative agent of dental caries, and human IgA, bacterial samples from human saliva were analyzed via FCM. The results showed that different profiles could be obtained depending on the oral hygiene status of the subjects. These results suggest that changes in the amount and type of antibodies that bind to oral bacteria may be an indicator for evaluating abnormalities in the oral flora. Therefore, the protocol established in this report could be applied as an evaluation method for alterations in the oral microbiota.

Changes in the structure of intestinal mucosal flora in colorectal cancer patients

To investigate the changes in bacterial flora in fecal samples, at the tumor loci and in adjacent mucosa in patients with colorectal cancer (CRC). We collected fecal samples from 13 patients with CRC and 20 healthy individuals and tumor and adjacent mucosa samples from 6 CRC patients. The differences in bacterial composition between the fecal and mucosa samples were analyzed with 16S rDNA sequencing and bioinformatics methods. We also detected the total number of bacteria in the feces using flow cytometry, isolated and identified the microorganisms in the fecal and mucosa samples using common bacterial culture media. We further tested the effects of 7 isolated bacterial strains on apoptosis of 3 CRC cell lines using lactate dehydrogenase detection kit. The bacterial α-diversity in the feces of healthy individuals and in adjacent mucosa of CRC patients was significantly higher than that in the feces and tumor mucosa in CRC patients (P < 0.05). Lactobacillaceae is a specific bacteria in the feces, while Escherichia, Enterococcus, and Fusobacterium are specific bacteria in tumor mucosa of CRC patients as compared with healthy individuals. Cell experiment with3 CRC cell lines showed that Bacteroides fragilis isolated from the tumor mucosa of CRC patients produced significant inhibitory effects on cell proliferation (P < 0.0001), while the isolated strain Fusobacterium nucleatum obviously promoted the proliferation of the cell lines (P < 0.001). The bacterial flora in the feces, tumor mucosa and adjacent mucosa of CRC patients is significantly different from that in the feces of healthy individuals, and the fecal flora of CRC patients can not represent the specific flora of the tumor mucosa. Inhibition of F. nucleatum colonization in the tumor mucosa and promoting B. fragilis colonization may prove beneficial for CRC treatment.