Enhancement of denitrification by sulfur-based carrier in sequencing batch reactor (SBR) for advanced wastewater treatment.

This study was to enhance the nitrogen removal efficiency in the sequencing batch reactor (SBR) process by adding sulfur-based carriers. The nitrogen removal efficiency of the control group was compared with that of the experimental group through a two-series operation of SBR1 without carrier and SBR2 with the carrier under the condition of no external carbon source. A total nitrogen (T-N) removal efficiency of 6.6%, 72.6%, and 79.9% was observed in SBR1, SBR2 (5%), and (10%), respectively. The T-N removal efficiency was improved in the system with carriers, which showed an increase in the removal efficiency of approximately 91.7%. The results suggest that the inclusion of the carrier led to an elevation in the sulfur ratio, implying an augmented surface area for sulfur-based denitrifying microorganisms. Additionally, CaCO3 contributed essential alkalinity for sulfur denitrification, thereby preventing a decline in pH. Regardless of the carrier, the efficiency of organic matter removal surpassed 89%, indicating that the sulfur-based carrier did not adversely affect the biological reaction associated with organic matter. Therefore, autotrophic denitrification was successfully performed using a sulfur carrier in the SBR process without an external carbon source, improving the nitrogen removal efficiency.

A Quasi-Experimental Study Investigating the Impact of a Lifestyle Redesign Program on the Well-Being of Korean University Students.

Background: Korean university students (KUS) face numerous challenges that can jeopardize their well-being, including academic stress, peer pressure, irregular sleep patterns, unhealthy eating habits, lack of physical exercise, and difficulties in time management, resulting in unhealthy habits and fluctuations in lifestyle. Consequently, there is a growing need for interventions tailored to this population. Aim: This study explored the effects of a Lifestyle Redesign (LR) intervention on Korean university students' well-being including occupational participation, satisfaction, perceived stress levels, and quality of life. Method: A quasi-experimental study with 33 KUS (17 intervention, 16 control) assessed the effects of a 10-week LR intervention on well-being of the students. Pre- and postintervention changes were measured using Canadian Occupational Performance Measure (COPM), Stress Response Inventory (SRI), and World Health Organization Quality of Life Scale Abbreviated Version (WHOQOL-BREF). The intervention, delivered by trained OTs, comprised of individual and group sessions. Results: Statistically significant improvement was observed in occupational performance. While statistical significance was not consistently achieved in the rest of other areas, the LR group displayed positive trends. The LR group exhibited higher COPM satisfaction scores, lower SRI scores (indicating reduced stress), and elevated WHOQOL-BREF scores compared to the control group. Conclusion: This study contributes to the understanding of the importance of addressing lifestyle changes and habits in the well-being of university students, especially in the context of academic stress and peer pressure. Future research with larger, more diverse samples and extended intervention periods may offer further insights into the benefits of LR programs in university settings.

Proposal of a novel subspecies: Alicyclobacillus hesperidum subspecies aegles.

Alicyclobacillus sp. DSM 11985T was isolated from geothermal soil but had not yet been classified at the species level. The strain produced guaiacol, which is of interest from the viewpoint of food spoilage in the food industry. 16S rRNA gene sequence analysis revealed that strain DSM 11985T was closely related (99.6 % similarity) to Alicyclobacillus hesperidum DSM 12489T. However, strains of A. hesperidum did not produce guaiacol; therefore, we performed the taxonomic characterization of strain DSM 11985T. The results showed that strain DSM 11985T and strains of A. hesperidum showed different phenotypic characteristics in biochemical/physiological tests including guaiacol production. Average nucleotide identity values between strain DSM 11985T and strain DSM 12489T were 95.4-95.9 %, and the in silico DNA-DNA hybridization value using the Genome-to-Genome Distance Calculator between strains DSM 11985T and DSM 12489T was 65.5 %. These values showed that strain DSM 11985T was genetically closely related but separated from strains of A. heparidum. From the above results, a novel subspecies of A. hesperidum, named Alicyclobacillus hesperidum subsp. aegles subsp. nov. is proposed. The type strain is DSM 11985T (=FR-12T=NBRC 113041T).

Exposure dose and temperature of chlorine on deterioration of thin-film composite membranes for reverse osmosis and nanofiltration.

In this study, the effect of chlorine, which is used as a chemical cleaning agent or disinfection agent on membrane deterioration, was analyzed under various conditions during the membrane process. Reverse osmosis (RO: ESPA2-LD and RE4040-BE) and nanofiltration (NF: NE4040-70) membranes made of polyamide (PA) thin film composite (TFC) were used for evaluation. Chlorine exposure was performed at doses ranging from 1000 ppm h to 10,000 ppm h using 10 ppm and 100 ppm, and temperatures from 10 °C to 30 °C. Raw water containing NaCl, MgSO4, and dextrose was used to compare the filtration performance after exposure to each of the conditions studied. Reduction in removal performance and enhancement in permeability were observed as chlorine exposure increased. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy and scanning electron microscope (SEM) were employed to determine the surface characteristics of the decomposed membranes. ATR-FTIR was used to compare the intensity of the peaks related to the TFC membrane. Based on the analysis, the state of membrane degradation was elucidated. SEM was used to confirm visual degradation of the membrane surface. Permeability and correlation analyses were performed on CnT as an index for determining membrane lifetime in order to investigate the power coefficient. The relative influence of the exposure concentration and time on membrane degradation was explored by comparing the power efficiency according to the exposure dose and temperature.

Investigating the effects of physical properties of sulphur-based carriers on autotrophic denitrification.

In this study, four sulphur-based carriers (C1-C4) which have different mass ratio of sodium silicate to carrier from 30% to 50% (C1-C3) and the existence of water (C4) were prepared in order to evaluate the effect of the different physical properties on denitrification in sulphur-based autotrophic processes. While the apparent density and the compressive strength decreased as the proportion of sodium silicate increased and water was added in the carriers, the average pore size and the porosity increased from 0.43 to 3.13 µm and from 38% to 67%, respectively. The treatment system using the carrier C4 with the highest surface area was stabilized most rapidly and achieved the highest nitrogen removal efficiency of 85.6 ± 5.0% during a relatively short HRT of 3 h. The efficiency of nitrate removal was enhanced by 36.9% due to the increase of the ratio of sodium silicate in the carriers from C1 to C3, and more 4.8% point of removal rate increased in the carrier C4 by adding water to the carrier C3. The sum of Thiobacillus and Sulfurimonas was obtained up to 65.90% among the microbial community in the carrier C4 which has the highest distribution (38.35%) of pore size above 20 µm considered to be favourable for retaining autotrophic denitrifiers. From the above results, it is obvious that the physical properties of the sulphur-based carrier and its ability of denitrification can be influenced significantly by the composition of the carrier.

Reduced proinflammatory activity of outer membrane vesicles of Tannerella forsythia treated with quorum sensing inhibitors.

Outer membrane vesicles (OMVs) of bacteria harbor physiologically active molecules, and quorum sensing inhibitors (QSIs) are expected to regulate bacterial virulence. In this study, we analyzed the proinflammatory activity of OMVs of the periodontal pathogen Tannerella forsythia treated with d-arabinose and d-galactose as QSIs, which inhibit the biofilm formation of periodontal pathogens and autoinducer 2 activity. Compared to OMVs of nontreated T. forsythia (TF OMVs), OMVs released from QSI-treated T. forsythia, designated TF ara-OMVs and TF gal-OMVs, showed reduced production of TNF-α, IL-1ß, IL-6, and IL-8 in THP-1 monocytes through decreased activation of NF-κB/MAPKs. Using a human NF-κB reporter cell line and bone marrow-derived macrophages from TLR2-/- mice, TF ara-OMVs and TF gal-OMVs showed less activation of TLR2 than TF OMVs. These results demonstrated that QSIs provide a dual advantage against bacterial infection by inhibiting bacterial biofilm formation and generating OMVs with reduced proinflammatory activity.

Effects of Nintedanib associated with Shenfu Injection on paraquat-induced lung injury in rats / 中华劳动卫生职业病杂志

Objective: To study the effects of Nintedanib associated with Shenfu Injection on lung injury induced by paraquat (PQ) intoxication. Methods: In September 2021, a total of 90 SD rats were divided into 5 groups in random, namely control group, PQ poisoning group, Shenfu Injection group, Nintedanib group and associated group, 18 rats in each group. Normal saline was given by gavage route to rats of control group, 20% PQ (80 mg/kg) was administered by gavage route to rats of other four groups. 6 hours after PQ gavage, Shenfu Injection group (12 ml/kg Shenfu Injection), Nintedanib group (60 mg/kg Nintedanib) and associated group (12 ml/kg Shenfu Injection and 60 mg/kg Nintedanib) were administered with medicine once a day. The levels of serum transforming growth factor beta1 (TGF-β1), interleukin-1 beta (IL-1β) were determined at 1, 3 and 7 d, respectively. The pathological changes of lung tissue, the ratio of wet weight and dry weight (W/D) of lung tissue, the levels of superoxide dismutase (SOD) and malondialdehyde (MDA) in lung tissue were observed and determined after 7 d. Western blot was used to analyse the expression levels of fibroblast growth factor receptor 1 (FGFR1), platelet derivation growth factor receptor alpha (PDGFRα), vascular endothelial growth factor receptor 2 (VEGFR2) in lung tissue after 7 d. Results: The levels of TGF-β1, IL-1β in all poisoning groups went up first and then went down. The levels of TGF-β1, IL-1β in associated group at 1, 3, 7 d were lower than that of PQ poisoning group, Shenfu Injection group and Nintedanib group at the same point (P<0.05). Pathological changes of lung tissue under the light microscopes showed that the degrees of hemorrhage, effusion and infiltration of inflammatory cells inside the alveolar space of Shenfu Injection group, Nintedanib group and associated group were milder than that of PQ poisoning group, and the midest in associated group. Compared with control group, the W/D of lung tissue was higher, the level of MDA in lung tissue was higher, while the level of SOD was lower, the expressions of FGFR1, PDGFRα and VEGFR2 in lung tissue were higher in PQ poisoning group (P<0.05). Compared with PQ poisoning group, Shenfu Injection group and Nintedanib group, the W/D of lung tissue was lower, the level of MDA in lung tissue was lower, while the level of SOD was higher, the expressions of FGFR1, PDGFRα and VEGFR2 in lung tissue were lower in associated group (P<0.05) . Conclusion: Nintedanib associated with Shenfu Injection can relieve lung injury of rats induced by PQ, which may be related to Nintedanib associated with Shenfu Injection can inhibit the activation of TGF-β1 and the expressions of FGFR1, PDGFRα, VEGFR2 in lung tissue of rats.

Activation of bone marrow-derived dendritic cells and CD4+ T cell differentiation by outer membrane vesicles of periodontal pathogens.

Outer membrane vesicles (OMVs) released from gram-negative bacteria harbor diverse molecules to communicate with host cells. In this study, we evaluated the OMVs of periodontal pathogens for their effects on the activation of dendritic cells and CD4+ T cell differentiation. OMVs of Porphyromonas gingivalis ATCC 33277, Treponema denticola ATCC 33521, and Tannerella forsythia ATCC 43037 ('red complex' pathogens) were isolated by density gradient ultracentrifugation. Mouse bone marrow-derived dendritic cells (BMDCs) were treated with OMVs, and OMV-primed BMDCs were cocultured with naïve CD4+ T cells to analyze the polarization of effector helper T cells. The OMVs upregulated maturation markers, including MHC class II, CD80, CD86, and CD40, on BMDCs. OMVs of P. gingivalis and T. forsythia induced the expression of the proinflammatory cytokines IL-1ß, IL-6, IL-23, and IL-12p70 in BMDCs. In T. denticola OMV-primed BMDCs, proinflammatory cytokines were poorly detected, which may be attributed to posttranslational degradation due to the highly proteolytic nature of OMVs. In cocultures of naïve CD4+ T cells with OMV-primed BMDCs, OMVs of P. gingivalis and T. denticola induced the differentiation of Th17 cells, whereas T. forsythia OMVs induced Th1 cell differentiation. These results demonstrate that OMVs derived from the 'red complex' periodontal pathogens induce maturation of BMDCs and differentiation of naïve CD4+ T cells to Th1 or Th17 cells.

Effects of extracellular vesicles derived from oral bacteria on osteoclast differentiation and activation.

Dysbiosis of the oral microbiota plays an important role in the progression of periodontitis, which is characterized by chronic inflammation and alveolar bone loss, and associated with systemic diseases. Bacterial extracellular vesicles (EVs) contain various bioactive molecules and show diverse effects on host environments depending on the bacterial species. Recently, we reported that EVs derived from Filifactor alocis, a Gram-positive periodontal pathogen, had osteoclastogenic activity. In the present study, we analysed the osteoclastogenic potency and immunostimulatory activity of EVs derived from the Gram-negative periodontal pathogens Porphyromonas gingivalis and Tannerella forsythia, the oral commensal bacterium Streptococcus oralis, and the gut probiotic strain Lactobacillus reuteri. Bacterial EVs were purified by density gradient ultracentrifugation using OptiPrep (iodixanol) reagent. EVs from P. gingivalis, T. forsythia, and S. oralis increased osteoclast differentiation and osteoclstogenic cytokine expression in osteoclast precursors, whereas EVs from L. reuteri did not. EVs from P. gingivalis, T. forsythia, and S. oralis preferentially activated Toll-like receptor 2 (TLR2) rather than TLR4 or TLR9, and induced osteoclastogenesis mainly through TLR2. The osteoclastogenic effects of EVs from P. gingivalis and T. forsythia were reduced by both lipoprotein lipase and polymyxin B, an inhibitor of lipopolysaccharide (LPS), while the osteoclastogenic effects of EVs from S. oralis were reduced by lipoprotein lipase alone. These results demonstrate that EVs from periodontal pathogens and oral commensal have osteoclastogenic activity through TLR2 activation by lipoproteins and/or LPS.

Inhibitory effect of d-arabinose on oral bacteria biofilm formation on titanium discs.

OBJECTIVES: Biofilm formation on dental implant surfaces can cause peri-implant mucositis and peri-implantitis. Lectins are involved in interactions between bacteria or between bacteria and their hosts. Disrupting these interactions via specific sugars can result in reduced adhesion and biofilm formation. The purpose of this study was to identify sugars that function as antiadhesion or antibiofilm agents on titanium discs. METHODS: Of the sugars tested, the sugars that did not affect the planktonic growth of Streptococcus oralis, Fusobacterium nucleatum, and Porphyromonas gingivalis were selected. The selected sugars were assessed for their ability to inhibit biofilm formation of bacteria in single and consortium species by crystal violet staining, confocal laser scanning microscopy after live/dead staining, and scanning electron microscopy. The sugars were evaluated for their ability to inhibit activity of the quorum sensing molecule autoinducer 2 (AI-2) by bioluminescence assay. RESULTS: Biofilm formation of single bacteria or consortia of S. oralis, F. nucleatum, and P. gingivalis on titanium discs was significantly inhibited in the presence of d-arabinose. Pretreating titanium discs with d-arabinose for 3 min inhibited biofilm formation at a level comparable to that observed when d-arabinose was present over the entire period, suggesting that d-arabinose had initial anti-adhesive activity. In addition, d-arabinose inhibited the activity of AI-2. CONCLUSIONS: d-Arabinose may be a good candidate for application as an antibiofilm agent and AI-2 inhibitor.

Evaluating coronary artery calcification with low-dose chest CT reconstructed by different kernels.

PURPOSE: To understand the reliability of low-dose chest computed tomography (LDCT) in coronary artery calcification (CAC) assessment and evaluate the performance of different reconstruction kernels against the standard cardiac computed tomography (CaCT) as reference. MATERIALS AND METHODS: Patients from the NELCIN-B3 screening program who underwent CaCT and LDCT scans were analyzed retrospectively. LDCT were reconstructed with smooth, standard, and sharp kernels (Group B1, B2 and B3) to compare against standard CaCT (Group A). The image quality was evaluated by noise value, signal-to-noise ratio (SNR), and contrast to noise ratio (CNR); moreover, radiation dose was recorded for both scans. Coronary artery calcification scores (CACS) were measured with volume, mass and Agatston standards. Agatston score was divided into four cardiovascular risk categories (0, 1-99, 100-399, and >400). The agreement in CACS and risk classification between LDCT and CaCT was analyzed by intra-group correlation coefficient (ICC) and Kappa test. RESULTS: The sensitivity of diagnosing CAC with LDCT was 98.5% (330/335) regardless of reconstruction kernels. Group B1 demonstrated the highest agreement in raw CACS (ICC volume 0.932; mass 0.904; Agatston 0.906; all p < 0.001) and risk classification (kappa 0.757, 95% CI 0.70-0.82). Smooth-kernel reconstruction achieved lower image noise, better SNR and CNR than other kernels. The effective radiation dose in of LDCT was 41.2% lower than that of the calcium scan (p < 0.001). CONCLUSION: Reconstructing LDCT with a smooth kernel in LDCT could provide a reliable imaging method to detect and quantitatively evaluate CAC, potentially expanding the application of LDCT lung screening to incidental findings of cardiovascular disease.

Removal effect of Candida albicans biofilms from the PMMA resin surface by using a manganese oxide nanozyme-doped diatom microbubbler.

To prevent oral candidiasis, removal of the Candida biofilms from dentures is important. However, common denture cleaners are insufficiently effective in removing biofilms. A manganese oxide (MnO2) nanozyme-doped diatom microbubbler (DM) can generate oxygen gas microbubbles by a catalase-mimicking activity in hydrogen peroxide (H2O2). DM can invade and destroy biofilms with the driving force of continuously generated microbubbles. In this study, the Candida biofilm removal efficiency by co-treatment of DM and H2O2 was investigated. Diatom particles were reacted with (3-aminopropyl)triethoxysilane to prepare amine-substituted diatom particles. These particles were reacted with potassium permanganate to fabricate DMs. The morphology and components of DM were analyzed by using a scanning electron microscope (SEM). Four types of denture base resin specimens on which biofilms of Candida albicans were formed were treated with phosphate-buffered saline (PBS group), Polident 5-Minute (Polident group), 0.12% chlorhexidine gluconate (CHX group), 3% H2O2 (H2O2 group), and co-treatment of 3 mg/mL of DM and 3% H2O2 (DM group). The biofilm removal effect of each group was quantitatively analyzed by crystal violet assay, and the results were visually confirmed by SEM images. After each treatment, the remaining C. albicans were stained with Hoechst 33342/propidium iodide, and observed with confocal laser scanning microscopy (CLSM) to evaluate the viability. MnO2 nanozyme sheets were successfully doped on the surface of the fabricated DM. Although biofilms were not effectively removed in the Polident and CHX groups, CLSM images showed that CHX was able to effectively kill C. albicans in the biofilms on all resin specimen types. According to the crystal violet analysis, the H2O2 groups removed the biofilms on heat-activated and 3D-printed resins (P < .01), but could not remove the biofilms on autopolymerizing and milled resins significantly (P = .1161 and P = .1401, respectively). The DM groups significantly removed C. albicans from all resin specimen types (P < .01).

Mechanism of chlorogenic acid reducing lipopolysaccharide-induced acute lung injury in mice by regulating miR-223/NLRP3 axis / 中南大学学报(医学版)

OBJECTIVES@#Chlorogenic acid has various physiological activities such as antibacterial, anti-inflammatory, and antiviral activities. Studies have shown that chlorogenic acid can alleviate the inflammatory response of mice with acute lung injury (ALI), but the specific mechanism is still unclear. This study aims to investigate whether chlorogenic acid attenuates lipopolysaccharide (LPS)-induced ALI in mice by regulating the microRNA-223 (miR-223)/nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) axis.@*METHODS@#SPF grade BALBc male mice were randomly divided into a control group, a model group, a chlorogenic acid group, a chlorogenic acid+miR-223 negative control (miR-223 NC) group, and a chlorogenic acid+miR-223 inhibitor (miR-223 antagomir) group, 10 mice in each group. Except the control group, the other groups were instilled with 4 mg/kg LPS through the airway to establish the ALI mouse model. After the modeling, the mice in the chlorogenic acid group were continuously given chlorogenic acid (100 mg/kg) by gavage for 7 d. The chlorogenic acid+miR-223 NC group and the chlorogenic acid+miR-223 antagomir group were given 100 mg/kg chlorogenic acid by gavage every day, and then were injected with 10 μL of miR-223 NC (0.5 nmol/μL) and miR-223 antagomir (0.5 nmol/μL) respectively for 7 consecutive days.The control group and the model group were replaced with normal saline. The lung tissues of mice were taken to measure the ratios of lung wet to dry weight (W/D). The bronchoalveolar lavage fluid of mice was collected to measure the levels of TNF-α, IL-6, and IL-1β by ELISA kit and to count the number of eosinophils (EOS), lymphocytes, neutrophils under light microscope. After HE staining, the pathological changes of lung tissues were observed and lung injury was scored. qRT-PCR method were used to determine the expression levels of miR-223 in lung tissues. Western blotting was used to determine the expression levels of NLRP3 protein in mouse lung tissues. Luciferase reporter assay was used to analyze the targeting relationship of miR-223 to NLRP3.@*RESULTS@#Compared with the control group, the lung W/D value, the lung injury score and the level of inflammatory factors in the bronchoalveolar lavage fluid were significantly increased in the model group (all P<0.05); the infiltration of inflammatory cells in the lung tissue was severe; the alveolar space was significantly increased; the alveolar wall was significantly thickened; the number of EOS, lymphocytes, and neutrophils in the bronchoalveolar lavage fluid was significantly increased (all P<0.05); the expression levels of miR-223 in lung tissue were significantly decreased (P<0.05); and the protein expression levels of NLRP3 were significantly increased (P<0.05). Compared with the model group, the W/D value of lungs, lung injury score, and levels of inflammatory factors in bronchoalveolar lavage fluid were significantly decreased in the chlorogenic acid group, the chlorogenic acid+miR-223 NC group, and the chlorogenic acid+miR-223 antagomir group (all P<0.05); lung tissues damage was alleviated; the numbers of EOS, lymphocytes, and neutrophils in bronchoalveolar lavage fluid were significantly decreased (all P<0.05); the expression levels of miR-223 in lung tissues were significantly increased (P<0.05); and the expression levels of NLRP3 protein were significantly decreased (P<0.05). Compared with the chlorogenic acid group, the lung W/D value, lung injury score, and inflammatory factor levels in the bronchoalveolar lavage fluid were significantly increased in the chlorogenic acid+miR-223 antagomir group (all P<0.05); lung tissue damage was aggravated; the number of EOS, lymphocytes and neutrophils in bronchoalveolar lavage fluid significantly increased (all P<0.05); the expression levels of miR-223 in lung tissues were significantly decreased (P<0.05); and the expression levels of NLRP3 protein were significantly increased (P<0.05). The results of luciferase reporter assay showed that miR-223 had a targeting relationship with NLRP3.@*CONCLUSIONS@#Chlorogenic acid may increase the level of miR-223, target the inhibition of NLRP3 expression, reduce LPS-induced inflammatory response in ALI mice, and alleviate pathological damage of lung tissues.

Inflammatory response of uric acid produced by Porphyromonas gingivalis gingipains.

Uric acid is a potential metabolite that serves as a danger-associated molecular pattern (DAMP) and induces inflammatory responses in sterile environments. Porphyromonas gingivalis is a keystone periodontopathogen, and its gingipain proteases play a critical role in the pathogenesis of periodontitis. In this study, we demonstrate that P. gingivalis gingipains play a role in THP-1 macrophage uric acid production by increasing the expression and activity of xanthine oxidoreductase (XOR). Uric acid sodium salt induces caspase-1 activation, cell death, and the expression of proinflammatory cytokines, including IL-1α, IL-6, and IL-8, in the human keratinocyte HOK-16B cell line. Our results suggest that gingipain-induced uric acid can mediate inflammation in periodontal tissue cells.

Use of d-galactose to regulate biofilm growth of oral streptococci.

In the oral microbial community, commensals can compete with pathogens and reduce their colonization in the oral cavity. A substance that can inhibit harmful bacteria and enrich beneficial bacteria is required to maintain oral health. The purpose of this study was to examine the effect of d-galactose on the biofilm formation of the cariogenic bacteria Streptococcus mutans and oral commensal streptococci and to evaluate their use in solution and in paste form. Biofilms of S. mutans, Streptococcus oralis, and Streptococcus mitis were formed on saliva-coated glass slips in the absence or presence of d-galactose and evaluated by staining with 1 % crystal violet. d-Galactose significantly inhibited the biofilm formation of S. mutans at concentrations ranging from 2 µM to 200 mM but increased the biofilm formation of S. oralis and S. mitis at concentrations of 2-200 mM. d-Galactose significantly inhibited three glucosyltransferase genes, gtfB, gtfC, and gtfD. The effect of d-galactose in the form of solution and paste was evaluated using bovine teeth. Pretreatment with 100 mM d-galactose on bovine teeth resulted in significantly reduced S. mutans biofilm formation. Our results suggest that d-galactose can be a candidate substance for the development of oral hygiene products to prevent caries by inhibiting the biofilm formation of S. mutans and simultaneously increasing the biofilm formation of commensal oral streptococci.

Characterization and immunostimulatory activity of extracellular vesicles from Filifactor alocis.

Filifactor alocis, a gram-positive, obligate anaerobic rod, is an emerging periodontal pathogen that is frequently isolated from patients with periodontitis, peri-implantitis, and apical periodontitis. Recent studies have shown that extracellular vesicles (EVs) from gram-negative periodontal pathogens, so-called outer membrane vesicles (OMVs), harbor various effector molecules responsible for inducing host inflammatory responses. However, there are no reports of EVs from F. alocis. In this study, we purified and characterized the protein profiles of EVs from F. alocis and investigated their immunostimulatory activity on human monocytic THP-1 and human oral keratinocyte HOK-16B cell lines. Highly pure EVs were obtained from F. alocis using density gradient ultracentrifugation. Nanoparticle tracking analysis and transmission electron microscopy showed that F. alocis EVs were between 50 and 270 nm in diameter. Proteome analysis identified 28 proteins, including lipoproteins, autolysins, F. alocis complement inhibitor (FACIN), transporter-related proteins, metabolism-related proteins, and ribosomal proteins. Human cytokine array analysis showed that F. alocis EVs remarkably induced the expression of CCL1, CCL2, MIP-1, CCL5, CXCL1, CXCL10, ICAM-1, IL-1ß, IL-1ra, IL-6, IL-8, MIF, SerpinE, and TNF-α in THP-1 cells and CXCL1, G-CSF, GM-CSF, IL-6, and IL-8 in HOK-16B cells. The immunostimulatory activity of F. alocis EVs was similar to that of the whole bacterial cells. Our findings provide new insight into the role of EVs from gram-positive oral bacteria in periodontal diseases.

Effects of vascular endothelial growth factor combined with platelet-derived growth factor-bb on the angiogenic and proliferative abilities of bone marrow mesenchymal stem cells / 中国组织工程研究

BACKGROUND: Bone tissue engineering provides a new path to treat critical-sized bone defects. However, a stable osteogenesis and osseointegration can only be insured via formation of an intact vascular network, which can achieve satisfactory therapeutic effects. Thereafter, angiogenesis is a challenge and difficulty in bone tissue engineering. OBJECTIVE: To investigate the effect of combined application of vascular endothelial growth factor (VEGF) and platelet-derived growth factor-BB (PDGF-BB) on proliferation and angiogenesis of bone marrow mesenchymal stem cells. METHODS: Bone marrow mesenchymal stem cells from Sprague-Dawley rats were cultured and isolated in vitro, and interfered with different concentrations of VEGF (20, 40, 60, 80, 100, 120 μg/L) and PDGF-BB (20, 40, 60, 80, 100, 120 μg/L) in combination or 100 μg/L VEGF, and 100 μg/L PDGF-BB alone. The optimum concentration of promoting cell proliferation was detected by cell counting kit-8 assay. The expression levels of angiopoietin-1, hypoxia-inducible factor-1α, hepatocyte growth factor and insulin-like growth factor were detected by RT-PCR at 7 and 14 days after intervention. RESULTS AND CONCLUSION: (1) After growth factors were added, the cell proliferative ability was significantly improved, and combined application revealed better effect. The optimal concentration grou was 80 μg/L VEGF+80 μg/L PDGF-BB. (2) Both VEGF and PDGF-BB could promote the mRNA expression levels of angiopoietin-1, hypoxia-inducible factor-1α, hepatocyte growth factor and insulin-like growth factor, and the effect was more obvious in combined application. (3) The mRNA expression levels of hypoxia-inducible factor-1α and hepatocyte growth factor were significantly increased with time (P < 0.05). The mRNA expression levels of angiopoietin-1 and insulin-like growth factor were significantly decreased with time (P < 0.05). (4) In vitro experimental results suggest that VEGF and PDGF-BB at the concentration of 80 μg/L can consistently promote angiogenesis, and the effect of combined application is better than that of single application.

Simultaneous Determination of Pyrrolidine Alkaloids and Their Nitrogen Oxides in Farfarae Flos by UPLC-MS/MS / 中国实验方剂学杂志

<b>Objective::To establish an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the simultaneous determination of 15 pyrrolidine alkaloids (PAs) and their nitrogen oxides, and determine the content of the 15 PAs in the 15 batches of Farfarae Flos samples obtained from different sources, in order to understand the distribution status of these 15 PAs in Farfarae Flos from different sources, and provide relevant references for the safe and rational use of this medicinal materials. <b>Method::The method was achieved by Agilent Eclipse Plus C₁₈ column (3.0 mm×150 mm, 1.8 μm) using a mobile phase made up of 0.05%formic acid and 2.5 mmol·L^-1 ammonium formate in water (A)-0.05%formic acid and 2.5 mmol·L^-1 ammonium formate in methanol(B). The flow rate and the injection volume were 0.4 mL·min^-1 and 2 μL, respectively. The column temperature was 40 ℃. The instrument was Agilent 1290-6470 QQQ ultra high performance liquid chromatography-triple quaternary bar mass spectrometer. The components were detected in multiple reaction monitoring mode by mass spectrometry with ionizationmode of ESI⁺. The content of the components measured in the samples was calculated by using the external standard method, and the difference between samples was analyzed based on RSD of different components. <b>Result::The established method had a high sensitivity and good separation degree. The results of methodological investigation met the requirements. The results showed that all of the 15 batches of Farfarae Flos contained PAs and their nitrogen oxides. These PAs had almost the same types of structure. There were significant differences in the content and distribution of PAs in Farfarae Flos obtained from different sources. <b>Conclusion::In general, Farfarae Flos contains pyrrolidine alkaloids and their nitrogen oxides. Senkirkine with a significant hepatotoxicity is the main compound. The content determination of PAs will provide scientific fundaments for the safe and effective use of Farfarae Flos.

Regulation of IL-24 in human oral keratinocytes stimulated with Tannerella forsythia.

Interleukin-24 is a pleiotropic immunoregulatory cytokine and a member of the IL-20R subfamily of the IL-10 family. The aim of this study was to investigate the regulation of IL-24 in the human oral keratinocyte cell line HOK-16B following infection with Tannerella forsythia, a major periodontal pathogen. T. forsythia induced the expression of IL-24 mRNA and the secretion of glycosylated IL-24 in HOK-16B cells. Glycosylation of IL-24 is linked to its solubility and bioavailability. T. forsythia-stimulated reactive oxygen species (ROS) induced the expression of IL-24, which was regulated by IL-6. The ROS inhibitor N-acetylcysteine and MAPK inhibitors significantly reduced the expression of IL-6 and IL-24 induced by T. forsythia. Recombinant human IL-24 significantly enhanced the expression of IL-1α, IL-8, CXCL10, and MCP-1 in HOK-16B cells. Together, these results indicate that ROS, MAPKs, and IL-6 comprise the axis of IL-24 expression in HOK-16B cells stimulated with T. forsythia. Thus, IL-24 may be involved in inflammation in oral keratinocytes.