Evaluation of Ellagic acid on the activities of oral bacteria with the use of adenosine triphosphate (ATP) bioluminescence assay

Ellagic acid, a natural herb extract from Galla Chinensis in traditional Chinese medicine, shows antimicrobial activity to certain bacteria. The present study evaluated the effect of Ellagic acid on the growth of oral bacteria as well as their generation of water-insoluble glucan and adhesion to salivacoated hydroxyapatite (S-HA) beads. Streptococcus mutans ATCC 25175, Streptococcus sanguis ATCC 10556, Streptococcus salivarius ATCC 25975, Actinomyces naeslundii ATCC 12104, Actinomyces viscosus ATCC 15987, Lactobacillus rhamnosus ATCC 53103, Porphyromonas gingivalis ATCC 33277 and Bacteroides forsythus ATCC 43037 were the bacterial cell lines used in this study. Antibacterial activity of Ellagic acid was determined by using adenosine triphosphate (ATP) bioluminescence assayat various concentrations from 0.125 to 8 mg/ml. Anthrone method was used to evaluate the level of water-insoluble glucan generated by oral bacteria. The numbers of 3H-thymidine labeled bacteria attached to S-HA was counted by scintillation counting method. Sprague Dawley rats were orally fed with 0.5mg/mL ellagic acid for 28 days and their behaviours and excretions were monitored. Ellagic acid reduced bacterial metabolic rates and inhibited the growth of the tested bacterial strains. The waterinsolubleglucan generated by S. mutans and its adhesion to S-HA were reduced. Ellagic acid demonstrated no toxicity in animals fed for 28 days. Ellagic acid might be a promising compound for the development of antimicrobial agents against oral pathogens in human, thereby reducing theincidence of dental caries

The impact of diabetes on the success of dental implants and periodontal healing

Dental implant is one of the restorative methods to replace missing teeth. As implants are directly anchored into bones, they provide stability, a more natural appearance, and minimize the risk of bone resorption and atrophy. However, studies found that diabetes mellitus patients had a slower healing process after surgery because of the reduction of vascular supply due to microangiopathies, decreased host defense, formation of advanced glycation end-products (AGEs), reduction of collagen production and increased collagenase activity. Diabetes mellitus patients may pose contraindications to dental implants. As a result of that, dental implantation failure rate in diabetic patients is much higher than that in non-diabetic patients. In this clinical experiment, we compared the amount of blood cells, and cytokines production 24 h post implantations, and the implant mobility 90 days post-surgery between controlled type 2 diabetic patients and the non-diabetic patients. It was aimed to investigate the suitability of diabetic patients to have dental implants and the efficacy of the amount of dental implants related to the success rates. 138 patients with type 2 diabetics and 140 healthy subjects, who had one to three adjacent edentulous spaces, were selected. Dental implantation surgeries were performed under local anesthesia. Wounds were sutured and all subjects were given 0.2% chlorohexidine mouthwash for 14 days. Complete blood picture and cytokines production were assayed before operation, as well as on days 1, 2, and 5 after implantation. Implant mobility and periodontal wound healing were monitored once in a fortnight up to 90 days. There were no statistically significant differences in the production of cytokines. In 138 diabetic patients, 255 implants were presented with second degree mobility 90 days after surgery while the same was demonstrated in 48 out of 346 implants from the healthy subjects. These implants were considered failures and were extracted. Implant failure in diabetics was significantly greater than that in non-diabetics when multiple adjoining implants were placed. © 2009 Academic Journals.published_or_final_versio

Detection of Bacteroides forsythus and Porphyromonas gingivalis in infected root canals during periapical periodontitis by 16S rDNA

Periapical periodontitis is termed when inflammation of the periodontium is caused by irritants of endodontic origin. Bacterial strains in the root canals were not easy to be identified by the traditional agar culture. In this study a 16S rDNA-based polymerase chain reaction detection method was used to determine the occurrence of Bacteroides forsythus and Porphyromonas gingivalis in chronic periapical periodontitis among Chinese patients. 217 patients with chronic periapcial periodontitis were recruited and a total of 266 teeth were collected. The subjects had no systemic diseases, no antibiotics taken, no root canal treatment (RCT) performed on the infected teeth in the last 3 months. The DNA of bacteria in the root canal was extracted and amplified using universal 16S rDNA primers. The amplification was performed to detect B. forsythus and P. gingivalis using oligonucleotide primers designed from species-specific 16S rDNA signature sequences. B. forsythus and P. gingivalis were detected in 26 and 40% of the participants, respectively. 24 out of 217 infected root canals demonstrated the existence of both types of bacteria, the utility of a 16S rDNA-based PCR detection method showed high sensitivity and high specificity to directly detect B. forsythus, P. gingivalis or other pulpal microorganisms from samples of root canal infections. The results indicated that B. forsythus or P. gingivalis might be a member of the microbiota associated with chronic periapical periodontitis and there was a strong association between the studied species and periodontitis. © 2009 Academic Journals.published_or_final_versio

Polistes olivaceous decreases biotic surface colonization

The objective of this investigation was to evaluate the anti-bacterial efficacy of the honeycomb of Polistes olivaceous on oral biotic surface (biofilm) model by means of pH response, population of oralbacteria and enamel mineralization. Three copies of a three-organism-bacterial consortium was grown on hydroxyapatite (HA) surfaces in a continuous culture system and exposed to repeated solution pulses of sucrose solution every 12 h to construct a cariogenic biofilm on the HA discs in the flow cells. One flow cell was only pulsed with 500 mol/ml of sucrose (S group). The second flow cell was pulsed with 500 mol/ml sucrose and 2.5 mg/ml P. olivaceous extract (P group). The third flow cell was pulsed with 500 mol/ml sucrose, 230 mg/L sodium fluoride and 0.2% chlorohexidine digluconate (C group). During the course of carbohydrate supplement, the pH of the S group dropped sharply compared with the others. The P group demonstrated pH recovery to baseline more easily than the S group (p < 0.05). The C group demonstrated very little pH drop. The P group displayed a lower level of colonization than the S group, which was reflected by a lower cariogenic bacterial count and a less compact biofilm especially after the third pulse. P. olivaceous suppresses bacteria growth and accelerates pH recovery.P. olivaceous may have stabilizing effect against cariogenic shift on the oral biofilm, preventing tooth decay

Polistes olivaceous decreases biotic surface colonization

The objective of this investigation was to evaluate the anti-bacterial efficacy of the honeycomb of Polistes olivaceous on oral biotic surface (biofilm) model by means of pH response, population of oral bacteria and enamel mineralization. Three copies of a three-organism-bacterial consortium was grown on hydroxyapatite (HA) surfaces in a continuous culture system and exposed to repeated solution pulses of sucrose solution every 12 h to construct a cariogenic biofilm on the HA discs in the flow cells. One flow cell was only pulsed with 500 μmol/ml of sucrose (S group). The second flow cell was pulsed with 500 μmol/ml sucrose and 2.5 mg/ml P. olivaceous extract (P group). The third flow cell was pulsed with 500 μmol/ml sucrose, 230 mg/L sodium fluoride and 0.2% chlorohexidine digluconate (C group). During the course of carbohydrate supplement, the pH of the S group dropped sharply compared with the others. The P group demonstrated pH recovery to baseline more easily than the S group (p < 0.05). The C group demonstrated very little pH drop. The P group displayed a lower level of colonization than the S group, which was reflected by a lower cariogenic bacterial count and a less compact biofilm especially after the third pulse. P. olivaceous suppresses bacteria growth and accelerates pH recovery. P. olivaceous may have stabilizing effect against cariogenic shift on the oral biofilm, preventing tooth decay. © 2009 Academic Journals.published_or_final_versio

Effects of various forms of lipopolysaccharide on the expression of inflammatory mediators and cardiac biomarkers in human cardiac fibroblasts and human coronary smooth muscle cells

Inflammation is an important event in the development of vascular diseases such as hypertension, atherosclerosis, and restenosis. The stimulation of lipopolysaccharide (LPS) from bacteria induces the release of critical proinflammatory cytokines that activate potent immune responses which may cause injury of cells in vivo and in vitro. Upon cardiac cell death caused by inflammation, the apoptotic cardiac cells express higher amount of cardiac markers. In this study, the effect of various LPS on human cardiac fibroblasts (HCFs) and human coronary smooth muscle cells (HCSMCs) were evaluated. Various forms of LPS were applied to HCFs and HCSMCs for 24, 48, 72 and 96 h. Proliferation rate of these cells was evaluated after stimulation. The levels of lactate dehydrogenase (LDH), N-terminal pro B-type natriuretic peptide (pro-BNP) and the MB isoenzyme of creatine kinase (CK-MB) were measured by an automation system. Cytokine levels in culture supernatants and extracted protein of cells were mixed and measured with IL-1β, IL-6 and IL-10 ELISA kits. Significant increase in the proliferation of two cardiac cells (P&lt;0.05) after incubation for 48 and 72 h was noted but not for 24 and 96 h (P&gt;0.05). Cardiac markers and inflammatory cytokines were significantly higher than control at 48 and 72 h (P&lt;0.05), which demonstrated that HCFs and HCMSCs were under inflammation leading to cell injury between 48 and 72 h. LPS is one of the factors giving rise to periodontal diseases, it is also involved in in vitro cardiac cell injury. Therefore, LPS may be used as a bio-marker to monitor local or systemic inflammation.Key words: Lipopolysaccharide, human cardiac fibroblasts, human coronary smooth muscle cell, inflammatory cytokines, cardiac bio-marker

Application of a Nano-antimicrobial film to prevent ventilator-associated pneumonia: A pilot study

Ventilator-associated pneumonia (VAP) is one of the most common hospital-associated infections and has accounted for approximately 15% of all hospital-associated infections. In 76% of the VAP cases, the same bacteria colonize the oral cavity and lungs. Oral care interventions may play a role in the prevention of VAP, yet more than half of the hospitals do not have specific policies for the oral care of intubated patients. Oral cavity interlinks with respiratory tracts and digestive tracts. After surgery has been performed in these areas, aerobic and anaerobic bacteria frequently induce operative wound infections in teeth, gingiva and supporting tissues of the teeth and tonsils. This study investigates the effects of a nanotechnology antimicrobial spray (JUC) on the incidence of VAP. 320 patients diagnosed with VAP were randomly divided into treatment and control groups. After using chlorhexidine mouthrinse, the treatment group used a nanotechnology antimicrobial spray to the nose and mouth. The control group was given normal saline. The incidence rate of VAP was significantly lower in the treatment (8.38%) than control group (54.24%) (p<0.01). A physical antimicrobial film is formed on the surface of oral and nasal mucosa after using the JUC spray which effectively reduces the microbial colonization in the sprayed areas, thus reducing and delaying the incidence of VAP. © 2011 Academic Journals.published_or_final_versio

The inhibitory effect of a herbal formula comprising ginseng and carthamus tinctorius on breast cancer

A compound (Zhu-xiang) from herbal extracts containing ginseng and carthamus tinctorius was used to treat the MDA-MB-231 breast cancer cell and normal human mammary gland cell lines. The inhibition of cell proliferation by Zhu-xiang, epirubicin, 5-fluorouracil and cyclophosphamide was determined by WST-1 assays. The apoptotic effect was studied by flow cytometry analysis of DNA strand breaks and ApopTag Peroxidase In Situ Apoptosis kit by the TUNEL assay. The proliferation index as well as cell cycle progression were also evaluated by flow cytometry using Ki-67 and propidium iodide respectively as markers. The Zhu-xiang showed significantly inhibition in cell proliferation and the inhibition was dose dependent. The inhibitory effect of Zhu-xiang was significantly greater than commonly used cytotoxic drugs. The inhibitory effect is a result of the induction of apoptosis, which is concentration- and time-dependent. DNA histograms indicate that the compound causes accumulation of cells mainly in the S phase. The viability of cells in breast solid tumours was measured by ATP bioluminescence assay to determine the drug-induced cytotoxicity of Zhu-xiang. The three different concentrations of Zhu-xiang all exhibited the ability to inhibit proliferation in solid tumour. Zhu-xiang could be a useful anti-cancer compound against breast cancer

Production of matrix metalloproteinases in specific subpopulations of human-patient breast cancer invading in three dimensional culture system

This article aims at investigating the effect of production of matrix metalloproteinases (MMP) in human breast cancer tissues by means of three dimensional culture system. Thirty-nine tumour samples were taken from breast cancer patients. The tumour blocks were cultured on sponge gel using the three dimensional culture system. Breast cancer cells began shedding into the culture medium after 24 hours of culture. The cells were stained with trypan blue dye to assess viability on days 2, 4, 6 and 8. The culture medium was collected at these time points and tested for matrix metalloproteinases (MMP) 1,2,3 and 9 activities. There was a progressive increase in migration of cancer cells into the gel and culture medium from day 2 to day 8 and the interval difference was statistically significant (F ratio = 4.06; p = 0.008). The levels of all the MMPs tested were also significantly raised (P<0.05 for all the MMPs tested). When the levels of MMPs were correlated with the metabolic activities in the gel, medium and tumour block, cells in block show no correlation whereas cells in gel correlated significantly with MMP-1 and MMP-3. Cancer cells in the culture medium correlated with MMP-9. In conclusion, there is a progressive migration of cancer cells outside the tumour block. The migration into the gel and culture medium is associated with progressive and differential production of MMPs. It is likely that the three dimensional culture model assists in the selection of different subpopulations of cancer cells with different invasion properties as exemplified by the differential production of MMP

Detection of Bacteroides forsythus and Porphyromonas gingivalis in infected root canals during periapical periodontitis by 16S rDNA

Periapical periodontitis is termed when inflammation of the periodontium is caused by irritants of endodontic origin. Bacterial strains in the root canals were not easy to be identified by the traditional agar culture. In this study a 16S rDNA-based polymerase chain reaction detection method was used to determine the occurrence of Bacteroides forsythus and Porphyromonas gingivalis in chronic periapical periodontitis among Chinese patients. 217 patients with chronic periapcial periodontitis were recruited and a total of 266 teeth were collected. The subjects had no systemic diseases, no antibiotics taken, no root canal treatment (RCT) performed on the infected teeth in the last 3 months. The DNA of bacteria in the root canal was extracted and amplified using universal 16S rDNA primers. The amplification was performed to detect B. forsythus and P. gingivalis using oligonucleotide primers designed fromspecies-specific 16S rDNA signature sequences. B. forsythus and P. gingivalis were detected in 26 and 40% of the participants, respectively. 24 out of 217 infected root canals demonstrated the existence of both types of bacteria, the utility of a 16S rDNA-based PCR detection method showed high sensitivity and high specificity to directly detect B. forsythus, P. gingivalis or other pulpal microorganisms from samples of root canal infections. The results indicated that B. forsythus or P. gingivalis might be a member of the microbiota associated with chronic periapical periodontitis and there was a strong association between the studied species and periodontitis