Application of Robotics in Orthodontics: A Systematic Review.

Robotics has various applications in dentistry, particularly in orthodontics, although the potential use of these technologies is not yet clear. This review aims to summarize the application of robotics in orthodontics and clarify its function and scope in clinical practice. Original articles addressing the application of robotics in any area of orthodontic practice were included, and review articles were excluded. PubMed, Google Scholar, Scopus, and DOAJ were searched from June to August 2023. The risk of bias was established using the risk of bias in non-randomized studies (ROBINS) and certainty assessment tools following the grading of recommendations, assessment, development, and evaluation (GRADE) guidelines. A narrative synthesis of the data was generated and presented according to its application in surgical and non-surgical orthodontics. The search retrieved 2,106 articles, of which 16 articles were selected for final data synthesis of research conducted between 2011 and 2023 in Asia, Europe, and North America. The application of robotics in surgical orthodontics helps guide orthognathic surgeries by reducing the margin of error, but it does not replace the work of a clinician. In non-surgical orthodontics, robotics assists in performing customized bending of orthodontic wires and simulating orthodontic movements, but its application is expensive. The articles collected for this synthesis exhibited a low risk of bias and high certainty, and the results indicated that the advantages of the application of robotics in orthodontics outweigh the disadvantages. This project was self-financed, and a previous protocol was registered at the PROSPERO site (registration number: CRD42023463531).

Food Insecurity and Dental Caries in Rural Mexican Populations.

Objective: Food insecurity (FI) is a priority for government and health organizations. Over 95% of the world's population has a carious lesion or will develop one before death. This study evaluated the association between FI and oral health in two rural communities in Chiapas, Mexico. Methods: The study was conducted with patients attending an oral health campaign for dental checkups. Data were collected between April and August 2017 using the Latin-American and Caribbean Scale of Food Security (ELCSA) and the International Caries Detection and Assessment System (ICDAS). We included 209 participants from Siltepec and Huehuetan, Mexico; 67% were women. Results: The results of the ELCSA were mild FI in 43% (n = 91), moderate FI in 22% (n = 45), and severe FI (n = 6) in 3%; 32% had food security. The ICDAS results were initial decay with a mean of 6.22, moderate decay with a mean of 1.81, and extensive decay with a mean of 1.77. Conclusions: FI is associated with dental caries, and food-insecure individuals have a higher probability of severe dental caries. In this study, the FI level was lower than in other rural populations in Mexico. Identifying these individuals and addressing the factors related to FI can be useful in the rural communities.

Prevalence of Oral Helicobacter pylori Infection in an Indigenous Community in Southwest Mexico.

Purpose: Epidemiological studies have been conducted to improve the health and economic quality of life of indigenous communities in Mexico. These studies have found that infections cause frequent health problems. Helicobacter pylori are responsible for conditions ranging from gastritis to stomach cancer. This study determined the prevalence of H. pylori in families from Siltepec, Chiapas, Mexico. Patient and Methods: Ninety-nine dental plaque samples from 36 families were studied. Real-time PCR was performed to detect H. pylori using previously reported primers. The Mann-Whitney U-test was used for the statistical analysis. According to the family role of H. pylori-positive individuals, the VacA s1/m1 genotype and CagA gene correlated. Results: The mother had the highest expression of VacA s1/m1-/cagA- with 19% (8/42), followed by the first child with 14.3% (6/42). The major roles for the vacA s1/m1+/cagA- were the mother and first child with 9.5% (4/42), followed by the remaining children with 4.8% (2/42). The vacA s1/m1-/cagA+ genotype was 7.1% (3/42) for the mother and 4.8% (2/42) for the father. Finally, the vacA s1/m1+/cagA+ genotype only appeared in the mother, son I, and son III with 2.4% (1/42). Conclusion: The vacA s1/m1/cagA genotypes predominated in the mother, suggesting potential transmission between the mother and child during the first years of life.

Effect of Culture Conditions of Lophocereus marginatus Endophytic Fungi on Yield and Anticancer and Antioxidant Activities.

Culture conditions affect the production of secondary metabolites in endophytic fungi. Therefore, the aim of the present study was to evaluate the yield and anticancer and antioxidant activity of endophytic fungi extracts from the cactus Lophocereus marginatus, under different culture conditions. The strains Penicillium citrinum, Aspergillus versicolor, Metarhizium anisopliae, and Cladosporium sp. were fermented in different culture media (potato dextrose agar, Czapeck broth, and malt broth), types of inoculums (spore or mycelium), and shaking conditions (150 rpm or static) for one week. Methanol extracts were obtained from mycelia, which was followed by determining their yields and evaluating their effect on L5178Y-R murine lymphoma cells growth and human peripheral blood mononuclear cells (PBMCs) viability, using the 3-[4,5dimethylthiazol-2-yl]2,5-diphenyl tetrazolium bromide reduction colorimetric assay. In addition, antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl test. We determined the half-maximal inhibitory concentration (IC50) values of tumor cell growth inhibition, the selectivity index (SI), and the antioxidant activity, as compared with the healthy cells control. The best yields were obtained with the Czapeck broth medium in all the evaluated strains, reaching values of 50.3%. Of the 48 extracts evaluated, only seven significantly (p < 0.01) inhibited tumor cell growth (IC50 < 250 µg/mL). A. versicolor extract showed the highest anticancer activity, after culturing spores (IC50 = 49.62 µg/mL; SI = 15.8) or mycelium (IC50 = 69.67 µg/mL; SI = 12.2) in malt broth, under static conditions. Extracts did not present significant antioxidant activity. In conclusion, we showed that culture conditions influenced the anticancer activity of L. marginatus endophytic fungi.

Cytotoxicity of Peruvian propolis and Psidium guajava on human gingival fibroblasts, PBMCs and HeLa cells.

It is indisputable that every day it is demonstrated that natural products present diverse therapeutic benefits, which has boosted their incorporation within various products for clinical use. However, this must be accompanied by knowledge of their effect on cell lines to ensure their use is safe. The objective of this study was to evaluate the cytotoxic effect of two ethanolic extracts based on Peruvian natural products, on three human cell lines. Cervical cancer cell lines (HeLa), human gingival fibroblasts (HGF-1 - ATCC CRL-2014) (HGF-1) and peripheral blood mononuclear cells (PBMCs) were cultured and subsequently treated with preparations of ethanolic extracts of propolis (EEP) and Psidium guajava (EEG) from a concentration of 50 mg/mL to 0.024 mg/mL, by the 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazole bromide reduction assay. At a concentration of 0.24 mg/mL EEG, viability of 99.7±1.24%, 99.8±2.2% and 99.7±2.7% was observed in HeLa, HGF-1 and PBMCs, respectively; >90% cell viability values were observed with EPP at 0.024 mg/mL, with HGF-1 showing the highest viability (96.9±1.15%). A dose-dependent effect was observed for both extracts with a decrease in cell viability as concentrations increased (up to 50 mg/mL). EEP and EEG extracts at low concentrations do not show cytotoxicity in human cell lines, these findings are an advance in the preclinical evaluation on their safety and open a continuity to further studies for their potential applications in dentistry and medicine.

Antimicrobial effectiveness of root canal sealers against Enterococcus faecalis.

We evaluated four root canal sealers to determine their antimicrobial effectiveness against E. faecalis. The direct contact test was used to measure the effectiveness of the study materials and close contact between bacteria on the kinetics of bacterial growth. The agar diffusion test (ADT) was also performed for comparison. Using one-way ANOVA and the F-test, significant differences between the sealers were confirmed. Whereas BioRoot endodontic sealer had an antimicrobial effect statistically similar to the zinc oxide-eugenol control (p=.99), EndoSequence sealer and AH Plus sealer both had a significantly lower antimicrobial effect than the control (p=.0000266 and p=.0000068, respectively).

SSEA-4 positive dental pulp stem cells from deciduous teeth and their induction to neural precursor cells.

BACKGROUND: Stage-specific embryonic antigen-4 (SSEA-4) is a marker for the identification of multipotent embryonic cells. It is also positive in neuroepithelial cells, precursor neural cells (NPC), and human dental pulp cells. The aim of this study was to evaluate the potential morphodifferentiation and histodifferentiation to NPC of SSEA-4 positive stem cells from human exfoliated deciduous teeth (SHED). METHODS: A SHED population in culture, positive to SSEA-4, was obtained by magnetic cell separation. The cells were characterized by immunohistochemistry and flow cytometry. Subsequently, a neurosphere assay was performed in a medium supplemented with basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF); afterward, cells were neurodifferenciated with a neurobasal medium. Finally, indirect immunohistochemistry was performed to identify neuronal markers. RESULTS: The morphological and histological changes in the SSEA-4 positive SHEDs were observed after induction with epidermal and fibroblast growth factors in neurobasal culture medium. At the end of induction, the markers Nestin, TuJ-1, and GFAP were identified. CONCLUSIONS: The findings show that SSEA-4 positive SHEDs have a behavior similar to neuronal precursor cells. Our findings indicate that the dental pulp of deciduous teeth is a promising source for regeneration therapies associated with neurodegenerative diseases or peripheral nerve alterations.

Antibacterial efficacy of a pH-neutral electrolyzed super-oxidized solution for nonsurgical periodontal treatment.

Objective: Mouthwash is effective in maintaining oral hygiene in patients; however, there is concern that it may adversely affect human oral mucosa. We evaluated a pH-neutral electrolyzed super-oxidized solution (ESS, tradename OxOral®) combined with dental scaling in periodontitis patients. This longitudinal study was conducted with 34 patients divided into three groups. The control group treated with scaling plus saline, the second with scaling plus ESS mouthwash, and another with scaling plus ESS mouthwash and gel. The plaque index (PI), gingival index (GI), and probing depth (PD) were determined before and after periodontal treatment. Results: The final PI and GI decreased compared with the initial measurements in the three treatment groups (p < 0.05). Scaling plus ESS mouthwash and gel significantly reduced the final PI, GI, and DP compared to the control group (p < 0.05). Conclusion: Our study shows the antiseptic properties of ESS with mouthwash and gel. Further studies are needed to verify the results.

Antimicrobial Effect of Calcium Hydroxide Combined with Electrolyzed Superoxidized Solution at Neutral pH on Enterococcus faecalis Growth.

OBJECTIVE: To evaluate the effect of the combination of calcium hydroxide (Ca(OH)2) and a novel electrolyzed superoxidized solution at neutral pH, known as OxOral® on Enterococcus faecalis growth in root canals. METHODS: Sixty human teeth were used, from which root canals were infected and randomly divided into the following treatment groups: saline solution, saline solution plus Ca(OH)2, OxOral®, and OxOral® plus Ca(OH)2. RESULTS: A permanent reduction in bacterial growth was observed at days 1, 6, 12, and 18 after OxOral® plus Ca(OH)2 treatment from 4.4 ± 0.074 log10 CFU/mL to 0.0 ± 0.001 log10 CFU/mL. In addition, alkaline conditions maintenance was observed from application time (pH = 12.2 ± 0.033) to 18 d posttreatment (pH = 12.6 ± 0.083). CONCLUSION: The combination of OxOral® and Ca(OH)2 provides an alkaline pH and inhibits E. faecalis growth into the root canals. Our study opens the possibility for further research on the use of OxOral® in endodontic therapy.

Prevalence of human papillomavirus in the oral cavity of an indigenous community from Southwest México.

Human papilloma virus (HPV) is a DNA virus associated with the development of cervical, penile, anal, vulvar, and oral cancers. In recent years, there has been an increase in oral cancer, which could be due to changes in sexual behavior in the general population. In México, there is scarce information on this regard, which prompted us to study HPV infection prevalence in the oral cavity of an indigenous community from the municipality of Siltepec, Chiapas, Mexico. Oral samples from 198 individuals were obtained with cytobrush for virus detection by nested PCR, using MY09/MY11 and GP5+/GP6+ primers, and positive samples were sequenced for HPV genotyping. We observed 12.1% HPV infection prevalence, which depended on gender, number of sexual partners, lack of using condoms, and oral sex practices. In contrast, no significant association between HPV infection and tobacco or alcohol consumption was detected. Furthermore, sequencing analyzes were performed where HPV-13 (21/24), -16 (2/24), -32 (1/24), -81 (1/24), and -83 (1/24) were evidenced and HPV-16 European/Asian and Asian/American E6 variants identified. These results demonstrated an important prevalence of HPV infection in the oral cavity of a Mexican indigenous community, where the predominant genotypes were associated with benign pathologies, and showed that high-risk genotype variants derived from different lineages.

Molecular detection of Helicobacter pylori based on the presence of cagA and vacA virulence genes in dental plaque from patients with periodontitis.

BACKGROUND/PURPOSE: Helicobacter pylori (H. pylori) infection is the most common in the world and is associated with various gastrointestinal pathologies, including chronic gastritis, peptic ulcers, and gastric cancer. The prevalence is associated with socioeconomic conditions, with this infection being more common in developing countries than in developed countries. The presence and permanence of H. pylori in the oral cavity has been reported, but its role is controversial. The aim of this study was to determine the prevalence of H. pylori in dental plaque of patients with periodontitis. MATERIALS AND METHODS: A cross-sectional study was carried out and Periodontal Screening and Recording (PSR) index was determined. 38 dental plaque samples were taken and total DNA was extracted and qPCR was performed. RESULTS: 60.5% of the samples (n = 23) were positive for the presence of H. pylori by the amplification of the 16S rRNA and vacA genes. In addition, cagA gene was detected in 21.7% (n = 5) of H. pylori-positive. A significant relationship between periodontal status and H. pylori oral infection was found (P ≤ 0.05); patients with initial and moderate periodontitis were the most affected with 39.1% and 30.4%, respectively. CONCLUSION: Our results suggest that the prevalence of H. pylori in the oral cavity could be related to the progression of periodontal disease. Therefore, oral hygiene and treatment for the elimination of oral H. pylori could stop the progression of periodontal disease.

Immunoinformatics Approach to Design a Novel Epitope-Based Oral Vaccine Against Helicobacter pylori.

Helicobacter pylori is an infectious agent that colonizes the gastric mucosa of half of the population worldwide. This bacterium has been recognized as belonging to group 1 carcinogen by the World Health Organization for the role in development of gastritis, peptic ulcers, and cancer. Due to the increase in resistance to antibiotics used in the anti-H. pylori therapy, the development of an effective vaccine is an alternative of great interest, which remains a challenge. Therefore, a rational, strategic, and efficient vaccine design against H. pylori is necessary where the use of the most current bioinformatics tools could help achieve it. In this study, immunoinformatics approach was used to design a novel multiepitope oral vaccine against H. pylori. Our multiepitope vaccine is composed of cholera toxin subunit B (CTB) that is used as a mucosal adjuvant to enhance vaccine immunogenicity for oral immunization. CTB fused to 11 epitopes predicted of pathogenic (UreB170-189, VacA459-478, CagA1103-1122, GGT106-126, NapA30-44, and OipA211-230) and colonization (HpaA33-52, FlaA487-506, FecA437-456, BabA129-149, and SabA540-559) proteins from H. pylori. CKS9 peptide (CKSTHPLSC) targets epithelial microfold cells to enhance vaccine uptake from the gut barrier. All sequences were joined to each other by proper linkers. The vaccine was modeled and validated to achieve a high-quality three-dimensional structure. The vaccine design was evaluated as nonallergenic, antigenic, soluble, and with an appropriate molecular weight and isoelectric point. Our results suggest that our newly designed vaccine could serve as a promising anti-H. pylori vaccine candidate.

Immunization with a Synthetic Helicobacter pylori Peptide Induces Secretory IgA Antibodies and Protects Mice against Infection.

Helicobacter pylori is a spiral Gram-negative bacterium associated with inflammation of the gastric mucosa, peptic ulcer, and gastric adenocarcinoma, whose treatment has failed due to antibiotic resistance and side effects. Furthermore, because there are no vaccines effective against H. pylori, an appropriate vaccine design targeting conserved/essential genes must be identified. In the present study, a H. pylori 50-52 kDa immunogen-derived peptide antigen with the sequence Met-Val-Thr-Leu-Ile-Asn-Asn-Glu (MVTLINNE) was used to immunize against H. pylori infection. For this, mice received an intraperitoneal injection of 100 µg of H. pylori peptide on the first week, followed by two weekly subcutaneous reinforcements and further 109 bacteria administration in the drinking water for 3 weeks. Thymic cells proliferative responses to concanavalin A, serum levels of IL-2, IL-4, IL-6, IL-10, IL-17, IFN-γ, and TNF-α cytokines, and IgG1, IgG2a, IgG2b, IgG3 IgM, and IgA immunoglobulins were evaluated. Significant (p < 0.05) increases on lymphoproliferation and spleen weights after immunization were observed. In contrast, infection significantly (p < 0.05) decreased lymphoproliferation, which was recovered in immunized mice. In addition, levels of serum TH1 and TH2 cytokines were not altered after immunization, except for the significant increase in IL-6 production in immunized and/or infected animals. Moreover, immunization correlated with plasma secretory IgA and IgG, whereas infection alone only elicited IgM antibodies. Peptide immunization protected 100% of mice against virulent H. pylori. MVTLINNE peptide deserves further research as an approach to the prophylaxis of H. pylori infection.

Dental iron precipitates in patients with Type 2 diabetes.

Diabetes mellitus (DM) is a frequent worldwide disease. There are currently more than 46 million people who suffer this disease in North America and the Caribbean. The objective of this study was to determine if there is an association between DM and the presence of iron precipitates (Fe2+) in dental structure. The third molar was extracted for reasons that merit extraction from 40 individuals with and without DM to analyze dentin tissue. Horizontal and longitudinal slices of tooth samples were made and later stained with 10% potassium cyanoferrate. The samples were observed by optical microscope to identify basophilic elements. A nonparametric Spearman correlation was performed to find an association between the quantitative (gender, group, and dentinal tissue) and qualitative variables (gender). The Mann-Whitney U test was used to find differences in the means of the nonparametric variables in two different groups in relation to the P value (<0.05). Iron elements were found in the predentin and circumpulpal dentin areas, and the results obtained showed a statistically significant difference between dentin tissue from patients with diabetes and those without. Individuals with Type 2 DM are prone to present iron precipitates in predentin and circumpulpal dentin tissue. Few iron elements were found in dental organs of individuals without DM.

Antimicrobial and Anti-Biofilm Effect of an Electrolyzed Superoxidized Solution at Neutral-pH against Helicobacter pylori.

The presence of Helicobacter pylori in the oral cavity has been associated to the failure of antimicrobial therapy in patients with gastrointestinal infection and the development of oral diseases. However, it has been reported that the maintenance of good oral hygiene can improve the therapeutic success rates, where the use of mouthwashes with anti-Helicobacter activity would help to achieve it. The aim was to evaluate the antimicrobial activity of OxOral® mouthwash against H. pylori and its effect on biofilm formation. The minimum inhibitory concentration (MIC) of OxOral® (pH = 6.4-7.5, ORP = 650-900 mV) against H. pylori was calculated testing serial dilutions 0.117-15 ppm against 1 × 108 CFU/mL of H. pylori (ATCC® 700824™) by broth microdilution method using 96-well plates. The H. pylori biofilm formation was determined by the optical density measurement at 600 nm from coverslips stained with 0.1% crystal violet. The gene expression of ureA, luxS, flaA, omp18, and lpxD were analyzed by RT-qPCR. OxOral® cytotoxicity was evaluated in a human gingival fibroblast cell line by MTT assay. MIC was of 3.75 ppm, with 99.7 ± 7.7% bacterial growth inhibition. In the negative control, the biofilm formation was observed, whereas when bacteria were treated with OxOral® at 0.234, 0.469, and 0.938 ppm, an inhibition of 35.5 ± 0.9%, 89.1 ± 1.2%, and 99.9 ± 5.5% were obtained, respectively. The gene expression analysis showed that flaA, omp18, and lpxD genes were down-regulated with OxOral® compared with control (p < 0.05). Low cytotoxicity of 16.5 ± 7.6% was observed at the highest dose (15 ppm); no significant differences were observed from 15 to 0.469 ppm compared to the control of untreated cells (p > 0.05). Our results reveal an important anti-Helicobacter activity of OxOral® and open the possibility of its therapeutic use new studies, which would increase the success rate of conventional therapies against H. pylori.

In Vitro Antimicrobial Activity and Downregulation of Virulence Gene Expression on Helicobacter pylori by Reuterin.

Helicobacter pylori is an infectious agent commonly associated with gastrointestinal diseases. The use of probiotics to treat this infection has been documented, however, their potential antimicrobial metabolites have not yet been investigated. In the present study, the effect of reuterin produced by Lactobacillus reuteri on H. pylori growth and virulence gene expression was evaluated. It was observed that reuterin caused significant (P < 0.05) H. pylori growth inhibition at concentrations from 0.08 to 20.48 mM, with minimal inhibitory concentrations (MICs) of 20.48 mM for H. pylori ATCC700824 and 10.24 mM for H. pylori ATCC43504. In a reuterin bacterial killing assay, it was observed that half of the MIC value for H. pylori (ATCC700824) significantly (P < 0.01) reduced colony numbers from 5.65 ± 0.35 to 3.78 ± 0.35 Log10 CFU/mL after 12 h of treatment and then increased them to 5.25 ± 0.23 Log10 CFU/mL at 24 h; at its MIC value (20.48 mM), reuterin abrogated (P < 0.01) H. pylori (ATCC700824) growth after 20 h of culture. In addition, reuterin significantly (P < 0.01) reduced H. pylori (ATCC 43504) colony numbers from 5.65 ± 0.35 to 4.1 ± 0.12 Log10 CFU/mL from 12 to 24 h of treatment and abrogated its growth at its MIC value (10.24 mM), after 20 h of treatment. Reuterin did not alter normal human gastric Hs738.St/Int cell viability at the concentrations tested for H. pylori strains. Furthermore, 10 µM reuterin was shown to significantly (P < 0.01) reduce mRNA relative expression levels of H. pylori virulence genes vacA and flaA at 3 h post-treatment, whose effect was higher at 6 h post-treatment, as measured by RT-qPCR. The observed direct antimicrobial effect and the downregulation of expression of virulence genes on H. pylori by reuterin may contribute to the understanding of the mechanisms of action of probiotics against H. pylori.

A Reliable and Reproducible Model for Assessing the Effect of Different Concentrations of α-Solanine on Rat Bone Marrow Mesenchymal Stem Cells.

Αlpha-solanine (α-solanine) is a glycoalkaloid present in potato (Solanum tuberosum). It has been of particular interest because of its toxicity and potential teratogenic effects that include abnormalities of the central nervous system, such as exencephaly, encephalocele, and anophthalmia. Various types of cell culture have been used as experimental models to determine the effect of α-solanine on cell physiology. The morphological changes in the mesenchymal stem cell upon exposure to α-solanine have not been established. This study aimed to describe a reliable and reproducible model for assessing the structural changes induced by exposure of mouse bone marrow mesenchymal stem cells (MSCs) to different concentrations of α-solanine for 24 h. The results demonstrate that nonlethal concentrations of α-solanine (2-6 µM) changed the morphology of the cells, including an increase in the number of nucleoli, suggesting elevated protein synthesis, and the formation of spicules. In addition, treatment with α-solanine reduced the number of adherent cells and the formation of colonies in culture. Immunophenotypic characterization and staining of MSCs are proposed as a reproducible method that allows description of cells exposed to the glycoalkaloid, α-solanine.

Prevalence of Helicobacter pylori vacA Genotypes and cagA Gene in Dental Plaque of Asymptomatic Mexican Children.

The variability in Helicobacter pylori vacA and cagA genes has been related to the progression of the gastrointestinal disease; also the presence of H. pylori in the oral cavity has been associated with periodontal disease in adults, but, in children without dyspeptic symptoms, little is known about this. We evaluated the prevalence of H. pylori and the presence of vacA/cagA genotypes in the oral cavity of Mexican children without dyspeptic symptoms. The gingival status was measured, and dental plaque samples (n = 100) were taken. 38% of children were positive for H. pylori 16S rRNA gene by qPCR. A significant association between H. pylori oral infection and gingival status was observed (P < 0.001). In 34.6% (9/26) of mild gingivitis cases, s1m2 genotype was found, while s1m1 was typed in 50% (3/6) of moderate gingivitis. The cagA prevalence among H. pylori-positive children was 80.8% (21/26), 83.3% (5/6), and 16.7% (1/6) of cases of mild gingivitis, moderate gingivitis, and nongingivitis, respectively (P < 0.001). The s1m1/cagA+ combinational genotype was the most detected in children with gingivitis. Our results suggest that the prevalence of H. pylori and detection of vacA/cagA genotypes-associated gastrointestinal disease in the oral cavity could be related to the progression of gingivitis in asymptomatic children.

Miconia sp. Increases mRNA Levels of PPAR Gamma and Inhibits Alpha Amylase and Alpha Glucosidase.

Diabetes mellitus is a public health problem worldwide. For this reason, ethanolic extract of Miconia sp. from Oaxaca, Mexico, was selected in search of an alternative against this disease. The effect of Miconia sp. on mRNA expression of PPARγ on cell line 3T3-L1, its effect on alpha amylase and alpha glucosidase, lipid accumulation during adipogenesis, and cell viability on VERO cells were evaluated. The mRNA levels of PPARγ increased on 1.393 ± 0.008 folds, lipid accumulation was increased by 29.55% with Miconia sp. extract and 34.57% with rosiglitazone, and α-amylase and α-glycosidase were inhibited with IC50 values from 28.23 ± 2.15 µg/mL and 1.95 ± 0.15 µg/mL, respectively; the IC50 on antiproliferative activity on VERO cells was 314.54 ± 45.40 µg/mL. In case of α-amylase and α-glycosidase assays, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of enzymatic activity. On the other hand, on antiproliferative activity, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of cell proliferation. It was concluded that the compounds present in Miconia sp. ethanolic extract increase mRNA expression of PPARγ, inhibit α-amylase and α-glucosidase, and increase lipid accumulation. It constitutes an alternative as adjuvant in diabetes mellitus treatment; therefore, we recommend continuing identifying the compounds responsible for its promising in vivo antidiabetic activity.

Antimicrobial properties and dental pulp stem cell cytotoxicity using carboxymethyl cellulose-silver nanoparticles deposited on titanium plates.

Objective: To evaluate the antimicrobial properties and dental pulp stem cells (DPSCs) cytotoxicity of synthesized carboxymethyl cellulose-silver nanoparticles impregnated on titanium plates. Material and methods: The antibacterial effect of silver nanoparticles in a carboxymethyl cellulose matrix impregnated on titanium plates (Ti-AgNPs) in three concentrations: 16%, 50% and 100% was determined by adding these to bacterial cultures of Streptococcus mutans and Porphyromonas gingivalis. The Ti-AgNPs cytotoxicity on DPSCs was determined using a fluorimetric cytotoxicity assay with 0.12% chlorhexidine as a positive control. Results: Silver nanoparticles in all concentrations were antimicrobial, with concentrations of 50% and 100% being more cytotoxic with 4% cell viability. Silver nanoparticles 16% had a cell viability of 95%, being less cytotoxic than 0.12% chlorhexidine. Conclusions: Silver nanoparticles are a promising structure because of their antimicrobial properties. These have high cell viability at a concentration of 16%, and are less toxic than chlorhexidine.