Tooth-Implant digital guide improves implantation accuracy in patients with periodontitis.

OBJECTIVE: To investigate the accuracy of Tooth-Implant digital guide-assisted implantation, explore the influence of periodontitis on the accuracy of the digital guide, and evaluate the effect of the residual abutment looseness after periodontitis treatment on the implant accuracy of the digital guide. METHODS: In this retrospective clinical study, 45 patients who received dental implantation at the Department of Periodontology, Beijing Stomatological Hospital affiliated with Capital Medical University, were selected and grouped. Group A consisted of non-periodontitis patients (n=15) who underwent Tooth-Implant digital guide-assisted implantation surgery. Group B was composed of periodontitis patients (n=15) who received Tooth-Implant digital guide-assisted implantation surgery. Group C included periodontitis patients (n=15) with freehand implantation. Three dental landmarks were identified to compare the planned implant position generated by the Tooth-Implant digital guide before implantation and the actual implant position in the same patient. Differences in implant depth, angle, shoulder and apex were analyzed before and after the implantation. RESULTS: There were statistical differences in implant depth, angle, shoulder, and apex between group B and group C. While statistical significance was found only in the implant angle and depth between group A and group B, not in the implant shoulder or apex. In periodontitis patients treated by Tooth-Implant digital guide-assisted implantation, significant differences were identified in implant depth and shoulder between non-abutment looseness and abutment looseness subgroups, but not in implant angle and apex. Under the digital guide-assisted implantation, no significant differences were found in implant depth, angle, shoulder and apex at different jaw positions, but at different tooth positions, significant differences were identified in implant angle and apex, not in implant depth and shoulder. The accuracy of Tooth-Implant digital guide-assisted implantation was consistent with previous data. CONCLUSIONS: The Tooth-Implant digital guide-assisted implantation has reliable implant accuracy that outperforms freehand implantation. Periodontitis is a factor affecting the accuracy of digital guide in dental implant placement, and this could be due to the looseness of residual abutments after systematic periodontal treatment. Different jaw positions have no impact on the accuracy of digital guide-assisted implantation, but different tooth positions have an impact on the accuracy of implant placement using a digital guide.

Assessing B-Z DNA Transitions in Solutions via Infrared Spectroscopy.

Z-DNA refers to the left-handed double-helix DNA that has attracted much attention because of its association with some specific biological functions. However, because of its low content and unstable conformation, Z-DNA is normally difficult to observe or identify. Up to now, there has been a lack of unified or standard analytical methods among diverse techniques for probing Z-DNA and its transformation conveniently. In this work, NaCl, MgCl2, and ethanol were utilized to induce d(GC)8 from B-DNA to Z-DNA in vitro, and Fourier transform infrared (FTIR) spectroscopy was employed to monitor the transformation of Z-DNA under different induction conditions. The structural changes during the transformation process were carefully examined, and the DNA chirality alterations were validated by the circular dichroism (CD) measurements. The Z-DNA characteristic signals in the 1450 cm-1-900 cm-1 region of the d(GC)8 infrared (IR) spectrum were observed, which include the peaks at 1320 cm-1, 1125 cm-1 and 925 cm-1, respectively. The intensity ratios of A1320/A970, A1125/A970, and A925/A970 increased with Z-DNA content in the transition process. Furthermore, compared with the CD spectra, the IR spectra showed higher sensitivity to Z-DNA, providing more information about the molecular structure change of DNA. Therefore, this study has established a more reliable FTIR analytical approach to assess BZ DNA conformational changes in solutions, which may help the understanding of the Z-DNA transition mechanism and promote the study of Z-DNA functions in biological systems.

Characterization of Z-DNA by Infrared Spectroscopy.

Infrared spectrum stems from the matter's absorption of light in the infrared (IR) light region. Generally, this infrared light absorption is due to the transition of vibrational and rotational energy levels of the involved molecule. Since different molecules have different structures and vibration modes, infrared spectroscopy can therefore be widely applied to analyze the chemical compositions and structures of molecules. Here we describe the method of application of infrared spectroscopy in the investigation of Z-DNA in cells, as infrared spectroscopy can distinguish DNA secondary structures sensitively and the band at 930 cm-1 is specifically attributed to the Z-form DNA. Based on the curve fitting, the relative content of Z-DNA in the cells may be evaluated.

Glutamine Deprivation Synergizes the Anticancer Effects of Cold Atmospheric Plasma on Esophageal Cancer Cells.

Esophageal cancer is a highly aggressive malignancy with a low response to standard anti-cancer therapies. There is an unmet need to develop new therapeutic strategies to improve the clinical outcomes of current treatments. Cold atmospheric plasma (CAP) is a promising approach for cancer treatment, and has displayed anticancer efficacy in multiple preclinical models. Recent studies have shown that the efficacy of CAP is positively correlated with intracellular reactive oxygen species (ROS) levels. This suggests that aggressively increasing intracellular ROS levels has the potential to further improve CAP-mediated anticancer efficacy. Glutamine plays an important role in cellular ROS scavenging after being converted to glutathione (GSH, a well-described antioxidant) under physiological conditions, so reducing intracellular glutamine levels seems to be a promising strategy. To test this hypothesis, we treated esophageal cancer cells with CAP while controlling the supply of glutamine. The results showed that glutamine did affect the anticancer effect of CAP, and the combination of CAP stimulation and glutamine deprivation significantly inhibited the proliferation of esophageal cancer cells compared to the control group (p < 0.05). Furthermore, flow cytometric analysis documented a significant increase in more than 10% in apoptosis and necrosis of esophageal cancer cells after this synergistic treatment compared to the control group (p < 0.05). Thus, these results provide the first direct evidence that the biological function of CAP can be modulated by glutamine levels and that combined CAP stimulation and glutamine deprivation represent a promising strategy for the future treatment of esophageal cancer.

Genome Sequences of Microbacterium foliorum Phages Anseraureola, Pondwater, and Yasuo.

Anseraureola, Pondwater, and Yasuo are bacteriophages with siphovirus morphology that infect Microbacterium foliorum NRRL B-24224. They were isolated from soil collected in Amherst, Massachusetts, and have genome lengths between 17,362 bp and 17,453 bp. These phages each contain 25 predicted protein-coding genes and are assigned to phage cluster EE.

A dynamic fluorescence probed glycolysis suppression process in HeLa cells treated with trichostatin A.

Acetylation can be regulated by histone deacetylases (HDACs) and histone acetyltransferases (HATs), and the imbalance between HDACs and HATs can lead to cancers. Trichostatin A (TSA), as one of the typical HDAC inhibitors (HDACis), may regulate the acetylation level and thus prevent the proliferation of cancer cells, in which the metabolic change of glycolysis is involved. However, the dynamic process of glycolysis has not yet been explored, and the mechanism is still elusive. In this work, we constructed GFP-actin-HeLa cells to observe the dynamic change of glycolysis in situ and found that the GFP fluorescence enhanced significantly after TSA treatment, which was consistent with the change of pH in the cells (pHi) depending on the change of lactate originated from glycolysis. Furthermore, we confirmed that the glycolysis was inhibited after TSA treatment, and this process was associated with HIF-1α and c-Myc regulation. As such, this work not only demonstrates the usefulness of the GFP fluorescent probe for monitoring the metabolic process of glycolysis in situ, but also sheds new light on the mechanism of glycolysis suppression in the cancer cells treated with HDACi.

Analysis of the Prevalence, Location, and Morphology of Maxillary Sinus Septa in a Northern Chinese Population by Cone Beam Computed Tomography.

Purpose: The purpose of this study is to survey the prevalence and morphology of the maxillary sinus septum, which might increase the rate of maxillary sinus membrane perforation during maxillary sinus floor elevation surgery, among northern Chinese, and to further analyze the relationship between gender, age, edentulous type, and prevalence of maxillary sinus septa. Methods: The cross-sectional retrospective study was based on an analysis of Cone Beam Computed Tomography (CBCT) images of maxillary sinus which had been obtained from patients who visited radiology department of Beijing Stomatology Hospital of Capital Medical University (Beijing, China) during the period from January 2019 to December 2019. The data of demographic characteristic, prevalence, position, direction, and morphology of maxillary sinus septum were collected and further analyzed by SPSS version 25.0.1 and R version 3.5.1 software program. Results: 595 patients were included in this study, and 1190 maxillary sinuses were analyzed and the incidence rate of the sinus septum was 46.9%. 399 (33.5%) sinuses had one or more septa in 279 (46.9%) patients. In addition, maxillary sinus septa incidence showed no significant differences among gender, age, and edentulous type. The segment second molar had the highest incidence rate of septa. Conclusion: In this study, a higher incidence of the maxillary sinus septum was found in the northern Chinese, and its distribution varied with its position, morphology, and direction.

Next generation sequencing of transcribed genes in ruminant γδ T cell populations.

Bovine γδ T cells are distinguished by expression of WC1, hybrid pattern recognition receptors and co-receptors to the T cell receptor (TCR), or their absence. WC1 molecules bind pathogens and the ability of γδ T cells to respond to pathogens largely correlates with their expression of particular WC1 genes. Following activation, the TCR and WC1 molecules co-localize and knocking down WC1 abrogates the ability of WC1-expressing γδ T cells to respond to antigen. It is known that these two major populations, WC1+ and WC1-, differ in their TCR gene expression and previous studies showed other differences using semi-quantitative RT-PCR and serial analysis of gene expression. Differences in genes expressed would influence the functional outcome when WC1+ vs. WC1- γδ T cells respond to pathogens. To identify unique aspects of their transcriptome, here we performed RNA-Seq of flow cytometrically sorted bovine WC1+ and WC1- γδ T cells and compared them to all mononuclear cells in blood. The greatest differences in gene expression were found between γδ T cells and other mononuclear cells and included those involved in lymphocyte activation and effector processes. Only minor differences occurred between ex vivo WC1+ vs. WC1- γδ T cells with those gene products being involved in cell adhesion and chemotaxis. After culturing cells from primed animals with Leptospira antigens major difference in the transcriptome was evident, with over 600 genes significantly differentially expressed including those focused on cytokine signaling. Unexpectedly, antigen-responding and non-responding populations of WC1+ γδ T cells had few differences in their transcriptomes outside of cytotoxic factors although they had more WC1-1, WC1-2 and WC1-13 transcripts. Through differential gene expression we were able to define properties of ex vivo and stimulated WC1+ cells which will be useful in understanding their functional biology.

Defining the caprine γδ T cell WC1 multigenic array and evaluation of its expressed sequences and gene structure conservation among goat breeds and relative to cattle.

Workshop cluster 1 (WC1) molecules are part of the scavenger receptor cysteine-rich (SRCR) superfamily and act as hybrid co-receptors for the γδ T cell receptor and as pattern recognition receptors for binding pathogens. These members of the CD163 gene family are expressed on γδ T cells in the blood of ruminants. While the presence of WC1+ γδ T cells in the blood of goats has been demonstrated using monoclonal antibodies, there was no information available about the goat WC1 gene family. The caprine WC1 multigenic array was characterized here for number, structure and expression of genes, and similarity to WC1 genes of cattle and among goat breeds. We found sequence for 17 complete WC1 genes and evidence for up to 30 SRCR a1 or d1 domains which represent distinct signature domains for individual genes. This suggests substantially more WC1 genes than in cattle. Moreover, goats had seven different WC1 gene structures of which 4 are unique to goats. Caprine WC1 genes also had multiple transcript splice variants of their intracytoplasmic domains that eliminated tyrosines shown previously to be important for signal transduction. The most distal WC1 SRCR a1 domains were highly conserved among goat breeds, but fewer were conserved between goats and cattle. Since goats have a greater number of WC1 genes and unique WC1 gene structures relative to cattle, goat WC1 molecules may have expanded functions. This finding may impact research on next-generation vaccines designed to stimulate γδ T cells.

The cannabinoid receptor I (CB1) enhanced the osteogenic differentiation of BMSCs by rescue impaired mitochondrial metabolism function under inflammatory condition.

BACKGROUND: Periodontitis is a chronic infectious disease leading to bone resorption and periodontal tissue disruption under inflammatory stimulation. The osteogenic differentiation ability of mesenchymal stem cells (MSCs) is impaired under the inflammatory environment, which limits the effect of treatment. The cannabinoid receptor I (CB1) is the main effector of the endogenous cannabinoid system (ECS), and our previous study verified that CB1 could enhance the osteo/dentinogenic differentiation of dental MSCs, which might be a target for alveolar bone regeneration. However, the effect of CB1 on the osteogenic differentiation of MSCs derived from bone remains unknown. In present study, we investigated the role and mechanism of CB1 on mitochondrial function and osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) under inflammatory environment. METHODS: Alkaline phosphatase (ALP) activity, alizarin red staining, quantitative calcium analysis, and osteogenic markers were used to detect the osteogenic differentiation ability of BMSCs. Real-time RT-PCR and Western blot were used to detect the gene expression. Seahorse Cell Mito Stress Test was used to detect the oxygen consumption rate (OCR). JC-10 assay was used to determine the mitochondrial membrane potential (MMP). RESULTS: CB1 increased osteogenic differentiation potential and mitochondrial energy metabolism, including the OCR, MMP, and enhanced the expressions of Nrf1 and Nrf2 in hBMSCs without or with TNF-α or INF-γ stimulation. Then, the inhibitor of mitochondrial electron transport chain (ETC), rotenone (ROT), inhibited the osteogenic differentiation in hBMSCs, and CB1 could rescue ROT impaired osteogenic differentiation potentials of hBMSCs without or with TNF-α or INF-γ stimulation. Activation of ETC by Coenzyme Q10 (CoQ10) could restore the impaired osteogenic differentiation of hBMSCs by depletion of CB1 without or with TNF-α or INF-γ stimulation. Mechanismly, CB1 could activate the JNK signaling pathway, p38 MAPK signaling pathway, and inhibit the Erk1/2 signaling pathway. CONCLUSIONS: The activating of CB1 enhanced the osteogenic differentiation by rescuing the mitochondrial metabolism function in hBMSCs under the inflammatory environment, suggesting that CB1 is a potential target for enhancing bone regeneration under the inflammatory environment.

Transcriptional programming and gene regulation in WC1+ γδ T cell subpopulations.

γδ T cells represent a high proportion of lymphocytes in the blood of ruminants with the majority expressing lineage-specific glycoproteins from the WC1 family. WC1 receptors are coded for by a multigenic array whose genes have variegated but stable expression among cells in the γδ T cell population. WC1 molecules function as hybrid pattern recognition receptors as well as co-receptors for the TCR and are required for responses by the cells. Because of the variegated gene expression, WC1+ γδ T cells can be divided into two main populations known as WC1.1+ and WC1.2+ based on monoclonal antibody reactivity with the expressed WC1 molecules. These subpopulations differ in their ability to respond to specific pathogens. Here, we showed these populations are established in the thymus and that WC1.1+ and WC1.2+ subpopulations have transcriptional programming that is consistent with stratification towards Tγδ1 or Tγδ17. WC1.1+ cells exhibited the Tγδ1 phenotype with greater transcription of Tbx21 and production of more IFNγ while the WC1.2+ subpopulation tended towards Tγδ17 programming producing higher levels of IL-17 and had greater transcription of Rorc. However, when activated both WC1+ subpopulations' cells transcribed Tbx21 and secreted IFNγ and IL-17 reflecting the complexity of these subpopulations defined by WC1 gene expression. The gene networks involved in development of these two subpopulations including expression of their archetypal genes wc1-3 (WC1.1+) and wc1-4 (WC1.2+) were unknown but we report that SOX-13, a γδ T cell fate-determining transcription factor, has differential occupancy on these WC1 gene loci and suggest a model for development of these subpopulations.

The Underrated Salivary Virome of Men Who Have Sex With Men Infected With HIV.

Salivary virome is important for oral ecosystem, but there are few reports on people living with HIV. We performed metagenomic sequencing to compare composition and functional genes of salivary virobiota between one HIV-negative and four HIV-positive groups in which participants were all men who have sex with men (MSM) with different immunosuppression statuses (five samples per group) to find the evidence that salivary virobiota plays a role in the pathogenesis of oral disease. Acute-stage subjects achieved a positive result of HIV RNA, but HIV antibody negative or indeterminate, whereas individuals with mild, moderate, and severe immunosuppression exhibited CD4+ T-lymphocyte counts of at least 500, 200-499, and less than 200 cells/µL or opportunistic infection, respectively. The results showed the composition of salivary virus genera in subjects with mild immunosuppression was the most similar to that in healthy people, followed by that in the acute stage; under severe immunosuppression, virus genera were suppressed and more similar to that under moderate immunosuppression. Furthermore, abnormally high abundance of Lymphocryptovirus was particularly obvious in MSM with HIV infection. Analysis of KEGG Pathway revealed that Caulobacter cell cycle, which affects cell duplication, became shorter in HIV-positive subjects. It is worth noting that in acute-stage participants, protein digestion and absorption related to the anti-HIV-1 activity of secretory leukocyte protease inhibitor was increased. Moreover, in the severely immunosuppressed subjects, glutathione metabolism, which is associated with the activation of lymphocytes, was enhanced. Nevertheless, the ecological dysbiosis in HIV-positive salivary virobiota possibly depended on the changes in blood viral load, and salivary dysfunction of MSM infected with HIV may be related to CD4 counts. Ribonucleoside diphosphate reductase subunit M1 in purine metabolism was negatively correlated, though weakly, to CD4 counts, which may be related to the promotion of HIV-1 DNA synthesis in peripheral blood lymphocytes. 7-Cyano-7-deazaguanine synthase in folate biosynthesis was weakly positively correlated with HIV viral load, suggesting that this compound was produced excessively to correct oral dysfunction for maintaining normal cell development. Despite the limited number of samples, the present study provided insight into the potential role of salivary virome in the oral function of HIV infected MSM.

Salivary microbial diversity at different stages of human immunodeficiency virus infection.

Human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) disrupts the host microbial balance. During disease progression, the oral microbial environment is altered in untreated people living with HIV/AIDS (PLWHA); however, no studies have reported changes in salivary microbial diversity during different stages of HIV infection. Therefore, in this study, we aimed to assess the relationships between immune dysfunction and changes in saliva microbiota. To this end, we collected saliva samples from 11 HIV-negative individuals and 44 PLWHA during different stages based on the Centers for Disease Control and Prevention criteria (stage 0, early stage during the first 6 months after infection; stages 1, 2, and 3 associated with CD4+ T-lymphocyte counts of ≥500, 200-499, and ≤200 or opportunistic infection, respectively). We analyzed salivary microbial community diversity using polymerase chain reaction amplification and Illumina MiSeq sequencing. We found that HIV-positive individuals had significantly greater alpha-diversity in the microbial community composition compared with HIV-negative controls (P < 0.05) except for AIDS (stage 3); however, the predominant salivary microbiota in the five groups remained similar. Porphyromonas in the four positive groups was the only genus that was significantly less abundant in the HIV-positive groups than in the control group (P < 0.05). There were some consistencies between the general abundance of salivary microbiota and AIDS disease progression. Lots of bacterial abundances in the saliva increased dramatically during the acute HIV infection (stage 0), and some of the negligible and abnormally proliferating bacteria in the asymptomatic stage showed a downward trend. Additionally, in the AIDS stage, partial inhibition was observed. Notably, Porphyromonas was closely related to the immune activation of HIV, showing a decline in abundance once infected with HIV. Solobacterium, which induces inflammation, was negatively correlated with CD4 counts. Overall, our findings provided important insights into changes in salivary microbial diversity in PLWHA.

Rose bengal-mediated photodynamic inactivation against periodontopathogens in vitro.

BACKGROUND: The main goal of periodontal therapy is to eliminate the spread of infection in the periodontium. Antimicrobial photodynamic therapy (aPDT) is a bactericidal method that has been recently introduced for controlling periodontal infection. The aim of this in vitro study was to evaluate the effect of aPDT using a combination of medium-power blue light-emitting diodes (LEDs) and rose bengal (RB) on selected key periodontopathogens. METHODS: Porphyromonas gingivalis ATCC33277, Aggregatibacter actinomycetemcomitans ATCC29523 and Fusobacterium nucleatum ATCC10953 were used in the experiments. Each bacterial suspension was irradiated with a blue LED (BL) (450-470 nm, output power density of 1.2 W/cm2) for 20-60 s (6-18 J/cm2), treated with RB (1 min), or subjected to a combination of RB treatment and BL irradiation (40 s, 12 J/cm2). All bacterial suspensions were serially diluted, plated and incubated anaerobically or microaerobically, and the numbers of colony-forming units (CFUs) were counted on day 7. One-way analysis of variance (ANOVA) and Tukey's HSD tests were used for statistical analysis. RESULTS: Treatment with BL irradiation from 6 to 18 J/cm2 did not significantly reduce the number of CFUs, whereas treatment with RB alone induced a low-to-high reduction in the bacterial CFUs in a dye concentration-dependent manner. Furthermore, the difference in the effects obtained with 16 µg/mL and 160 µg/mL RB was not statistically significant. Treatment with the BL at 12 J/cm2 combined with 160 µg/mL RB yielded maximal log reductions of 3.03, 4.2 and 2.23 in P. gingivalis, A. actinomycetemcomitans and F. nucleatum CFUs, respectively. CONCLUSION: Within the limits of this study, the three periodontal pathogens, especially A. actinomycetemcomitans, were susceptible to photodynamic inactivation by the combination of the BL and RB. RB-mediated aPDT may offer a viable alternative tool for periodontal pathogen treatment, especially for A. actinomycetemcomitans eradication. aPDT may be a valuable tool for the treatment of periodontal diseases, particularly those in which A. actinomycetemcomitans is a dominating pathogen.

Low Dose of Trichostatin A Improves Radiation Resistance by Activating Akt/Nrf2-Dependent Antioxidation Pathway in Cancer Cells.

Numerous studies have shown that histone deacetylase inhibitors (HDACis) improve cellular acetylation while also enhancing the radiation sensitivity. In this work, however, we confirmed that low-dose trichostatin A (TSA) as a typical HDACi could reduce rather than increase the radiosensitivity of cancer cells, while the cellular acetylation was also increased with TSA-induced epigenetic modification. The surviving fraction of HeLa/HepG2 cells pretreated with 25 nM TSA for 24 h was higher at 1 Gy/2 Gy of γ-ray radiation than that of the cells with the same radiation dose but without TSA pretreatment. To understand the underlying mechanism, we investigated the effect of low-dose TSA on HO-1, SOD and CAT induction and activating Akt together with its downstream Nrf2 signaling pathway. Our results indicated that TSA activated HO-1, SOD and CAT expression by increasing the phosphorylation level of Nrf2 in an Akt-dependent manner. In addition, we also observed that the 25-nM-TSA-pretreated group showed a significant increase in the antioxidant capacity in terms of SOD and CAT activities. Therefore, our results suggest that low-dose TSA can activate the Akt/Nrf2 pathway and upregulate expression of HO-1, SOD and CAT to stimulate the cellular defense mechanism. This work demonstrates that low-dose TSA treatment may activate the adaptation mechanism against the oxidative stress induced by ionizing radiation, and application of HDACi treatment should be undertaken with caution to avoid its possible radioresistance in radiotherapy.

Gene characterization and expression of the γδ T cell co-receptor WC1 in sheep.

Sheep are known to express the hybrid co-receptor/pattern recognition receptor WC1 on their γδ T cells but details of the ovine WC1 multigenic array and gene expression were unknown. Annotation of the sheep genome assembly (Oar_rambouillet_v1.0) yielded 15 complete and 42 partial WC1 genes predicted to code for six different protein structures. RT-PCR amplification of the most distal scavenger receptor cysteine rich (SRCR) domain known as a1, which serves as the gene signature, from genomic and cDNA templates verified the majority of annotated genes. As for cattle and goats, sheep a1 domain sequences included WC1.1 and WC1.2 types. A unique ovine gene, WC1-16, had multiple SRCR a-pattern domains in tandem similar to one found in goats. Intracytoplasmic domains of WC1 transcripts had splice variants that may affect signal transduction. The larger number of WC1 genes in sheep and differences in structures and splice variants relative to cattle could have implications in expression patterns and engagement of γδ T cells by pathogens or vaccine constructs.

Development of a CD63 Aptamer for Efficient Cancer Immunochemistry and Immunoaffinity-Based Exosome Isolation.

CD63, a member of transmembrane-4-superfamily of tetraspanin proteins and a highly N-glycosylated type III lysosomal membrane protein, is known to regulate malignancy of various types of cancers such as melanoma and breast cancer and serves as a potential marker for cancer detection. Recently, its important role as a classic exosome marker was also emphasized. In this work, via using a magnetic bead-based competitive SELEX (systematic evolution of ligands by exponential enrichment) procedure and introducing a 0.5M NaCl as elution buffer, we identified two DNA aptamers (CD63-1 and CD63-2) with high affinity and specificity to CD63 protein (Kd = 38.71nM and 78.43, respectively). Furthermore, CD63-1 was found to be efficient in binding CD63 positive cells, including breast cancer MDA-MB-231 cells and CD63-overexpressed HEK293T cells, with a medium binding affinity (Kd~ 100 nM) as assessed by flow cytometry. When immunostaining assay was performed using clinical breast cancer biopsy, the CD63-1 aptamer demonstrated a comparable diagnostic efficacy for CD63 positive breast cancer with commercial antibodies. After developing a magnetic bead-based exosome immunoaffinity separation system using CD63-1 aptamer, it was found that this bead-based system could effectively isolate exosomes from both MDA-MB-231 and HT29 cell culture medium. Importantly, the introduction of the NaCl elution in this work enabled the isolation of native exosomes via a simple 0.5M NaCl incubation step. Based on these results, we firmly believe that the developed aptamers could be useful towards efficient isolation of native state exosomes from clinical samples and various theranostic applications for CD63-positive cancers.

In vitro antimicrobial effect of curcumin-based photodynamic therapy on Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans.

BACKGROUND: Photodynamic therapy (PDT) is a bactericidal method, which has recently been introduced in the field of dental medicine and therapy. Curcumin, a compound isolated from Curcuma longa L., exerts potent phototoxic effects at micromolar concentrations. The aim of our study was to explore the in vitro antimicrobial effect of curcumin-based PDT on two major etiological agents of periodontitis, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. METHODS: P. gingivalis ATCC33277 and A. actinomycetemcomitans ATCC24523 suspension was irradiated with blue LED (BL) (450-470 nm, output power density 1.2 W/cm2) for 20-60 s (6-18 J/cm2), treated with curcumin (2 min), or subjected to a combination of curcumin treatment and BL irradiation (60 s, 18 J/cm2). A suspension of chlorhexidine gluconate (CHG) was used as the positive control. All bacterial suspensions used were serially diluted, plated, and incubated anaerobically or microaerobically. The numbers of colony-forming units (CFUs) were counted on day 7. One-way analysis of variance (ANOVA) and Tukey's HSD tests were used for statistical analysis. RESULTS: BL irradiation at 6, 12, and 18 J/cm2 alone reduced the number of CFUs of both P. gingivalis and A. actinomycetemcomitans, but the reduction was not statistically significant. Compared with BL irradiation alone, curcumin solution at 20 µmol/L used alone achieved a lower reduction in the number of CFUs. Combined use of BL at 18 J/cm2 20 µmol/L curcumin treatment yielded a log reduction of 0.43 and 1.51 for P. gingivalis and A. actinomycetemcomitans CFUs, respectively. Suspensions treated with 0.12 % CHG showed a log reduction of 0.29 and 0.28 for P. gingivalis and A. actinomycetemcomitans CFUs, respectively. CONCLUSIONS: Although the bactericidal and growth-inhibitory effects of BL alone on P. gingivalis and A. actinomycetemcomitans were not significant, A. actinomycetemcomitans was susceptible to photodynamic inactivation by the combination of BL and curcumin.

Remodeling Chromatin Induces Z-DNA Conformation Detected through Fourier Transform Infrared Spectroscopy.

The SWI/SNF complex is a highly conserved chromatin remodeling complex and can hydrolyze ATP by its catalytic subunit BRG1 or BRM to reconstruct the chromatin. To investigate whether this ATP-dependent chromatin remodeling could affect the DNA conformation, we therefore regulated (knocked down or overexpressed) BRG1/BRM in the cells and applied Fourier transform infrared (FTIR) spectroscopy to probe DNA conformational changes. As a result, we found that BRG1/BRM was indeed associated with the DNA conformational changes, in which knockdown of BRG1/BRM reduced Z-DNA conformation, while overexpression of BRG1/BRM enhanced Z-DNA conformation. This Z-DNA conformational transformation was also verified using the Z-DNA-binding proteins. Therefore, this work has provided a direct analytical tool to probe Z-DNA transformation upon ATP-dependent chromatin remodeling.

Methanandamide diminish the Porphyromonas gingivalis lipopolysaccharide induced response in human periodontal ligament cells.

BACKGROUND: The endocannabinoid system is involved in the regulation of periodontal tissue homeostasis. Synthetic cannabinoid methanandamide (Meth-AEA) has improved stability and affinity to cannabinoid receptors compared to its endogenous analog anandamide. In the present study, we investigated the effect of methanandamide on the production of pro-inflammatory mediators in primary human periodontal ligament cells (hPdLCs). METHODS: hPdLCs were treated with Meth-AEA for 24 h, and the resulting production of interleukin (IL)-6, IL-8, and monocyte chemotactic protein (MCP)-1 was measured in the absence or the presence of Porphyromonas gingivalis lipopolysaccharide (LPS). Additionally, the effect of Meth-AEA on the proliferation/viability of hPdLCs was measured by the MTT method. RESULTS: Methanandamide at a concentration of 10 µM significantly inhibited P. gingivalis LPS induced production of IL-6, IL-8, and MCP-1. Basal production of IL-6 and IL-8 was slightly enhanced by 10 µM Meth-AEA. No effect of Meth-AEA on the basal production of MCP-1 was observed. Meth-AEA in concentrations up to 10 µM did not affect the proliferation/viability of hPdLCs, but significantly inhibited it at a concentration of 30 µM. CONCLUSION: Our study suggests that the inflammatory response in periodontal ligament cells could be influenced by the activation of the cannabinoid system, which might be potentially involved in the progression of periodontal disease.