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Antibacterial and antifungal activities of six plant-derived flavonoids representing two different structural groups were evaluated against standard strains of Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, Acinetobacter baumannii, Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis and their drug-resistant isolates, as well as fungi (Candida albicans, C. krusei) using the microdilution broth method. Herpes simplex virus Type-1 and Parainfluenza-3 virus were employed for antiviral assessment of the flavonoids using Madin-Darby bovine kidney and Vero cell lines. Ampicillin, gentamycin, ofloxacin, levofloxacin, fluconazole, ketoconazole, acyclovir, and oseltamivir were used as the control agents. All tested compounds (32-128 microg/ml) showed strong antimicrobial and antifungal activities against isolated strains of P. aeruginosa, A. baumanni, S. aureus, and C. krusei. Rutin, 5,7-dimethoxyflavanone-4'-O-beta-D-glucopyranoside and 5,7,3'-trihydroxy-flavanone-4'-O-beta-D-glucopyranoside (0.2-0.05 microg/ml) were active against PI-3, while 5,7-dimethoxyflavanone-4'-O-[2''-O-(5'''-O-trans-cinnamoyl)-beta-D-apiofuranosyl]-beta-D-glucopyranoside (0.16-0.2 microg/ml) inhibited potently HSV-1.

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The aim of this study was to compare one-visit indirect pulp treatment (IPT), two-visit IPT, and direct complete excavation (DCE) of deciduous and young permanent molars with deep carious lesions from clinical and microbiological points of view. One hundred thirty-five teeth (83 deciduous molars and 52 young permanent molars) were included in the study. The teeth were randomly selected and treated either with one-visit IPT, two-visit IPT, or DCE. For two-visit IPT, the final excavation was performed after a period of 3 months. The color, consistency, and humidity of the dentin at the cavity floor were recorded for clinical assessment, and dentin samples were obtained from all teeth. Dentin samples were microbiologically investigated for the total number of colony forming units, mutans streptococci, and lactobacilli. The results showed bacterial growth in 63.8% of the dentin samples in one-visit IPT, while in two-visit IPT, bacterial growth was observed in all of the samples (100%) after the first excavation. When the cavities were reopened before the final excavation, the number of samples with positive growth had decreased significantly (44.4%), and after the final excavation, the number of the samples with positive growth had decreased to 2.2%. In the DCE group, only 25.6% of the samples revealed bacterial growth. No statistical difference was found between deciduous and permanent molars in any of the treatment groups in terms of microbiologic results (p > 0.05). In conclusion, although none of the treatment methods completely eliminated the viable microorganisms during the initial excavations, a dramatic reduction in bacterial growth was detected during the treatment stages of two-visit IPT.

A series of chemically functionalized porous aromatic frameworks (PAFs) have been synthesized and deployed within mixed matrix membranes for gas separation. This series of PAFs delivered for the first time simultaneous control of selective gas transport and physical aging within the membranes. New composites including native and metallated fullerenes were also prepared, and exhibited exceptional increases in their porosity, which in turn resulted in ultrafast gas transport. CO 2 permeability following PAF-1-Li 6 C 60 infusion within poly-(trimethylsilylpropyne) (PTMSP) was as high as 50,600 Barrer, a 70 % improvement. Remarkably, just 9 % of this permeation rate diminished after one year of physical aging, compared to 74 % in the native polymer. A series of characterization techniques revealed this phenomenon to be due to intercalation of polymer chains within the PAF pores, the strength of which being controlled by the levels of chemical functionalization and porosity. The membranes were exploited for gas separations, in particular the stripping of CO 2 from natural gas.

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Corneal endothelial cells (CECs) are responsible for maintaining the transparency of the human cornea. Loss of CECs results in blindness, requiring corneal transplantation. In this study, fabrication of biocompatible and biodegradable poly(ethylene glycol) (PEG)-based hydrogel films (PHFs) for the regeneration and transplantation of CECs is described. The 50-μm thin hydrogel films have similar or greater tensile strengths to human corneal tissue. Light transmission studies reveal that the films are >98% optically transparent, while in vitro degradation studies demonstrate their biodegradation characteristics. Cell culture studies demonstrate the regeneration of sheep corneal endothelium on the PHFs. Although sheep CECs do not regenerate in vivo, these cells proliferate on the films with natural morphology and become 100% confluent within 7 d. Implantation of the PHFs into live sheep corneas demonstrates the robustness of the films for surgical purposes. Regular slit lamp examinations and histology of the cornea after 28 d following surgery reveal minimal inflammatory responses and no toxicity, indicating that the films are benign. The results of this study suggest that PHFs are excellent candidates as platforms for the regeneration and transplantation of CECs as a result of their favorable biocompatibility, degradability, mechanical, and optical properties.

In the current study, the results of antibacterial, antifungal, and antiviral activity tests of four flavonoid derivatives, scandenone (1), tiliroside (2), quercetin-3,7-O-α-ʟ-dirhamnoside (3), and kaempferol-3,7-O-α-ʟ-dirhamnoside (4), are presented. Antibacterial and antifungal activities of these compounds were tested against Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, Acinetobacter baumannii, Staphylococcus aureus, Bacillus subtilis, and Enterococcus faecalis, as well as the fungus Candida albicans by a microdilution method. On the other hand, both DNA virus Herpes simplex (HSV) and RNA virus Parainfluenza-3 (PI-3) were employed for antiviral assessment of the compounds using Madin- Darby bovine kidney and Vero cell lines. According to our data, all of the compounds tested were found to be quite active against S. aureus and E. faecalis with MIC values of 0.5 μg/ml, followed by E. coli (2 μg/ml), K. pneumoniae (4 μg/ml), A. baumannii (8 μg/ml), and B. subtilis (8 μg/ml), while they inhibited C. albicans at 1 μg/ml as potent as ketoconazole. However, only compound 3 displayed an antiviral effect towards PI-3 in the range of 8- 32 μg/ml of inhibitory concentration for cytopathogenic effect (CPE).