ABSTRACT
Quercetin derivatives are widespread in the plant kingdom and exhibit various biological actions. The aim of this study was to investigate the structure-activity relationships of quercetin derivatives, with a focus on the influence of functional groups and sugar composition on their antioxidant capacity. A series of quercetin derivatives were therefore prepared and assessed for their DPPH radical scavenging properties. Isoquercetin O-gallates were more potent radical scavengers than quercetin. The systematic analysis highlights the importance of the distribution of hydroxy substituents in isoquercetin O-gallates to their potency.
Subject(s)
Free Radical Scavengers , Quercetin , Antioxidants/pharmacology , Biphenyl Compounds/pharmacology , Free Radical Scavengers/chemical synthesis , Free Radical Scavengers/chemistry , Free Radical Scavengers/pharmacology , Molecular Structure , Picrates/pharmacology , Quercetin/analogs & derivatives , Quercetin/chemical synthesis , Quercetin/chemistry , Quercetin/pharmacology , Structure-Activity RelationshipABSTRACT
Novel 316 L stainless steel (SS) foam with 85% porosity and an open pore diameter of 70-440 µm was developed for hard tissue application. The foam sheet with a 200-µm diameter had superior cell proliferation and penetration as identified through in vitro experiments. Calcification of human osteosarcoma cells in the SS foam was observed. Multi-layered foam preparation is a potential alternative technique that satisfies multi-functional requirements such as cell penetration and binding strength to the solid metal. In tensile tests, Young's modulus and the strength of the SS foam were 4.0 GPa and 11.2 MPa respectively, which is comparable with human cancellous bone.
Subject(s)
Biocompatible Materials , Osteosarcoma/pathology , Stainless Steel , Calcification, Physiologic , Cell Proliferation , Humans , Materials Testing/methods , Tumor Cells, CulturedABSTRACT
Therapeutic options for postoperative infection in gastrointestinal surgery are limited. To identify new treatment alternatives, the Japan Society for Surgical Infection conducted a multicenter prospective, randomized, controlled clinical trial comparing the efficacy of intravenous ciprofloxacin (CIP IV) and intravenous meropenem (MEM IV). Between July 2005 and May 2008, the trial recruited patients who developed postoperative infection or had suspected infectious systemic inflammatory response syndrome after elective clean-contaminated gastrointestinal surgery. All patients had received prophylactic postoperative antibiotic treatment. Patients received either intravenous CIP IV 300 mg b.i.d. or MEM IV 500 mg b.i.d. A total of 205 patients from 31 institutions were enrolled. Of these, 101 were randomized to CIP IV and 104 to MEM IV. There were 100 and 102 in the intent-to-treat (ITT)/safety population and 75 and 77 in the per-protocol (PP) population. There was no significant difference between CIP IV and MEM IV in terms of clinical efficacy, bacteriological efficacy, incidence of adverse drug reactions, duration of antimicrobial treatment, or relapse/reactivation. Overall clinical success PP population) was high in both treatment groups: 85.3% (64/75) for CIP IV and 89.6% (69/77) for MEM IV, although the non-inferiority of CIP IV was not demonstrated (difference -4.3%, 95% CI -14.8, 6.2). In patients who had undergone upper gastrointestinal surgery, success was 88.5% (23/26) for CIP IV and 85.2% (23/27) for MEM IV. Intravenous ciprofloxacin is as effective as intravenous meropenem in the empiric therapy of postoperative infection after gastrointestinal surgery.
Subject(s)
Anti-Bacterial Agents , Bacterial Infections/drug therapy , Ciprofloxacin , Digestive System Surgical Procedures/adverse effects , Surgical Wound Infection/drug therapy , Thienamycins , Aged , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/adverse effects , Anti-Bacterial Agents/therapeutic use , Bacterial Infections/microbiology , Ciprofloxacin/administration & dosage , Ciprofloxacin/adverse effects , Ciprofloxacin/therapeutic use , Female , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Humans , Injections, Intravenous , Japan , Male , Meropenem , Middle Aged , Prospective Studies , Surgical Wound Infection/microbiology , Thienamycins/administration & dosage , Thienamycins/adverse effects , Thienamycins/therapeutic use , Treatment OutcomeABSTRACT
Using checkerboard and time-kill assays, the in-vitro activity of ciprofloxacin alone and in combination with flomoxef against clinical Bacteroides fragilis strains was evaluated. In addition, the microbiological efficacy of this combination was compared with that of ciprofloxacin plus clindamycin. In 88% of the 25 strains tested, the combination of ciprofloxacin plus flomoxef exhibited a synergistic or an additive effect, whereas only 56% of the 25 strains ( P< 0.01, chi(2) test) tested with the combination of ciprofloxacin plus clindamycin exhibited similar effects. In a time-kill study using 7 clinical strains, a synergistic or additive effect of the combination of ciprofloxacin plus flomoxef was observed in all 7 strains. In conclusion, the combination of ciprofloxacin plus flomoxef is very active against B. fragilis, suggesting that this combination may be very useful in the treatment of aerobic and B. fragilis mixed infections, because ciprofloxacin has an expanded spectrum against aerobes.
