Flexural strength,biocompatibility, and antimicrobial activity of a polymethyl methacrylate denture resin enhanced with graphene and silver nanoparticles

Clinical Oral Investigations - The study evaluates the effect of adding graphene-Ag nanoparticles (G-AgNp) to a PMMA auto-polymerizing resin, with focus on antibacterial activity, cytotoxicity,...     

Influence of inorganic filler content on the radiopacity of dental resin cements

Digital radiography was used to measure the radiopacity of 18 resin cements to determine the influence of inorganic filler content on radiopacity. Four disk specimens (n=4) of each light-curing cement were digitally radiographed alongside an aluminum step wedge using an intraoral sensor (XIOS Plus, Sirona, Germany), and their mean gray value measured. Percentage of filler by weight was determined using an analytical combustion furnace. Data were statistically analyzed using one-way ANOVA and Tukey's test (α=0.05). All materials were more radiopaque than dentin and 12 materials were more radiopaque than enamel. Filler percentage ranged between 17.36 to 53.56 vol% and radiopacity between 1.02 to 3.40 mm Al. There were no statistically significant differences in inorganic filler percentage and radiopacity among the different shades of the same material (p>0.05), but the highest radiopacity was measured for the material which contained a higher percentage of filler.     

New Definition Criteria of Myocardial Dysfunction in Patients with Liver Cirrhosis: A Speckle Tracking and Tissue Doppler Imaging Study

There are no clear recommendations regarding cirrhotic cardiomyopathy (CC) evaluation in patients with pre-transplant liver cirrhosis. The roles of new methods, tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE) in the diagnosis and prognosis of cirrhotic cardiomyopathy remain controversial. We investigated the utility of TDI/STE parameters in cirrhotic cardiomyopathy diagnosis and also in predicting mortality in patients with liver cirrhosis. Left/right ventricular function was studied using conventional TDI (velocities) and STE (strain/strain rate). We assessed left ventricular diastolic dysfunction, graded into four new classes (I/Ia/II/III). Serum NTproBNP (N-terminal prohormone of brain natriuretic peptide), troponin I, β-crosslaps, QTc interval, arterial compliance and endothelial function were measured. Liver-specific scores (Child–Pugh, MELD, MELDNa) were computed. There was a 1-y follow-up visit to determine mortality. We observed resting biventricular diastolic myocardial dysfunction, not presently included in the definition of cirrhotic cardiomyopathy. We provided an improved characterization of cardiac dysfunction in patients with liver cirrhosis. This might change the current definition. However, the utility of STE/TDI parameters in predicting long-term mortality in patients with liver cirrhosis remains controversial.     

Seeing the forest beyond the trees: Predicting survival in burn patients with machine learning

Background

This study aims to identify predictors of survival for burn patients at the patient and hospital level using machine learning techniques.

The impact of Sambucus nigra L. extract on inflammation,oxidative stress and tissue remodeling in a rat model of lipopolysaccharide-induced subacute rhinosinusitis

Inflammopharmacology - Rhinosinusitis is a common disorder related to inflammation of paranasal sinuses and nasal cavity mucosa. Herbal medicines could be an option in the treatment of...     

Testing endodontic sealers on human umbilical vein endothelial cells

The toxic potential of the endodontic sealers ingredients, especially the unreacted monomer, that can irritate the periapical tissue and interfere with the healing process, thus having a negative impact on the biocompatibility of the material. The aim of this study was to evaluate the influence of three experimental endodontic sealers on cells viability in vitro. Human umbilical vein endothelial cells (HUVEC) were used. The experiments were done with solid samples and extracts of sealers in artificial saliva and water. The experiments evaluated the cytotoxicity of the residual monomers that resulted from the tested composites. The decrease in cell viability was quantified by colorimetric measurement of formazan. The components of the sealers dissolved in artificial saliva and water were determined by high performance liquid chromatography (HPLC). The HUVEC are a novelty for testing the endodontic sealers biocompatibility, with certain advantages compared to other cell types used in the literature, e.g. HELA cells, fibroblasts. The data showed that cytotoxicity was directly linked with the unreacted monomer — 2-hydroxyethyl methacrylate (HEMA) present in these composites. Two of the three formulations had little or no cytotoxic effect, which makes them suitable for further testing in order to be used in endodontic treatment.     

Inhibition of intestinal glucose absorption by anti-diabetic medicinal plants derived from the James Bay Cree traditional pharmacopeia

Background

Type II diabetes and obesity are major health problems worldwide and aboriginal peoples are particularly at risk. To address this problem in Canadian native populations who find modern pharmaceuticals culturally inappropriate, our team is testing the traditional pharmacopeia of the James Bay Cree for anti-diabetic and anti-obesity activities. More specifically, the aim of the present study was to define the effects of traditional plants on intestinal glucose absorption, an under-appreciated anti-hyperglycaemic and anti-obesity activity.

Methods

Crude ethanol extracts of 17 Boreal forest medicinal plants were tested in vitro using the Caco-2 human enterocytic cell line and in vivo using an oral glucose tolerance test.

Results

Thirteen of seventeen extracts were observed to significantly inhibit uptake when administered simultaneously with ³H-deoxyglucose. Inhibition was dose-dependent and, in a few cases, even surpassed that induced by a combination of the positive controls. To validate these effects in vivo, four plant extracts were administered by intragastric gavage at 250 mg/kg to normal rats simultaneously with a 3 g/kg bolus of glucose. This resulted in a decrease in peak glycaemia by approximately 40% for two of them. Similarly, only 2 extracts reduced glucose transport after long term incubation and this could be related to reductions in the expression of SGLT-1 or GLUT-2 proteins.

Conclusions

These findings indicate that competitive inhibition of intestinal glucose uptake can be achieved by crude extracts of medicinal plants. Such extracts could be taken with meals to control postprandial glycaemia and reduce caloric intake in high risk populations that are positively inclined towards traditional medicine.     

Photodamaging effects of porphyrins and chitosan on primary human keratinocytes and carcinoma cell cultures

Background Photodynamic therapy (PDT) is a non‐surgical method for treating non‐melanoma skin cancer and precancerous lesions which involves the activation of a photosensitizer by visible light to produce activated oxygen species within target cells, resulting in the destruction of the latter. The present study evaluates the effect of PDT on primary normal and basal cell carcinoma cultures in vitro. Methods Primary human keratinocytes and carcinoma cell cultures were exposed to various concentrations of 5,10,15,20‐tetra‐(para‐methoxyphenyl) porphyrin (TMP) and its zinc compound (Zn‐TMP) for 24 hours, with or without chitosan, and then irradiated using a PDT lamp (630 nm, 6 J/cm²). The effects of PDT were assessed using a 3‐(4,5‐dimethylthiazol‐2‐yl)‐5‐(3‐carboxymethoxyphenyl)‐2‐(4‐sulfophenyl)‐2H‐tetrazolium inner salt (MTS) assay and an immunocytochemical method with Annexin V‐FITC for detecting apoptosis. Results Both tested substances, TMP and Zn‐TMP, had a phototoxic effect on primary human carcinoma cell cultures in concentrations of 1–100 μg/ml, which positively correlated with the concentration of the photosensitizer. There was no phototoxic effect on primary keratinocytes, probably because of the preferential accumulation of photosensitizing substances in tumoral cells. Administration of chitosan in association with photosensitizing substances increased cell viability compared with photosensitizers alone, exerting a cytoprotective effect. Conclusions The study demonstrates that the photodynamic activity of TMP and its metalloporphyrin derivative is limited to primary human carcinoma cells and suggests that these porphyrins could be efficiently used in PDT in vivo.