Ultraviolet light

About: Ultraviolet light is a research topic. Over the lifetime, 49494 publications have been published within this topic receiving 843151 citations.

Efficacy of dilute betadine solution irrigation in the prevention of postoperative infection of spinal surgery

Abstract: Study design Prospective, single-blinded, randomized study. Objectives To evaluate the efficacy of dilute betadine irrigation of spinal surgical wounds in prevention of postoperative wound infection. Summary and background Deep wound infection is a serious complication of spinal surgery that can jeopardize patient outcomes and increase costs. Povidoneiodine is a widely used antiseptic with bactericidal activity against a wide spectrum of pathogens, including methicillin-resistant Staphylococcus aureus. The aim of this study was to evaluate the efficacy of dilute betadine solution in the prevention of wound infection after spinal surgery. Methods Four hundred and fourteen patients undergoing spinal surgery were randomly assigned to two groups. In group 1 (208 patients), surgical wounds were irrigated with dilute betadine solution (3.5% betadine) before wound closure. Betadine irrigation was not used in group 2 (206 patients). Otherwise, perioperative management was the same for both groups. Results Mean length of follow-up was 15.5 months in both groups (range, 6-24 months). No wound infection occurred in group 1. One superficial infection (0.5%) and six deep infections (2.9%) occurred in group 2. The differences between the deep infection rate (P = 0.0146) and total infection rate (P = 0.0072) were significant between the two groups. Conclusions Our report is the first prospective, single-blinded, randomized study to evaluate the clinical effectiveness of dilute betadine solution irrigation for prevention of wound infection following spinal surgery. We recommended this simple and inexpensive measure following spinal surgery, particularly in patients with accidental wound contamination, risk factors for wound infection, or undergoing surgery in the absence of routine ultraviolet light, laminar flow, and isolation suits.

Modified TiO2 photocatalyst for CO2 photocatalytic reduction: An overview

Abstract: The photocatalytic pathway to reduce carbon dioxide (CO2) to fuel, an artificial photosynthesis process, is a futuristic and ultimate way to combat the energy crisis and CO2 emission issues. The most widely used catalyst for photocatalytic reactions is titanium dioxide (TiO2) due to its availability, chemical stability, low cost and resistant to corrosion. Although TiO2 photocatalyst suffers due to its wide band gap (only can be activated under ultraviolet light irradiation) and high electron-hole recombination rate, it remained as a precursor for the development of visible light responsive materials for CO2 reduction through different modifications, such as doping of metal, nonmetal, semiconductors etc. There is a significant improvement in CO2 conversion using the visible light responsive TiO2 based catalysts. The product distribution due to the photocatalytic reduction of CO2 highly depends on the band gap and band edges of the catalyst. The understanding in the mechanistic pathway of CO2 reduction is very important to design the catalyst for the production of desired product. This present paper provides an overview of research and development of TiO2 based photo-catalysts for CO2 reduction and focuses on the improvement of the photocatalyst based on the band gap engineering, charge transfer and CO2 adsorption. Moreover, the challenges and future prospect in the developing modified TiO2 for photocatalytic reduction of CO2 has also been discussed.

Selective vulnerability of the blood-brain barrier in chemically induced lesions.

Abstract: 1. Vulnerability of the blood-brain barrier to unilateral intracarotid perfusion with chemical injurious agents was studied with the application of various fluorescent and radioactive tracers. 2. Evans blue when bound to albumin fluoresces brightly red in formalin-fixed frozen sections as viewed under ultraviolet light provides a useful and convenient tool for microscopic localization of this tracer. 3. Using fluorescent labeled albumin as a single indicator, several patterns of its abnormal penetration through the damaged cerebral vessels have been elucidated and discussed. 4. Tracing the BBB damage by concurrent intrasystemic administration of albumin and γ-globulin labeled with contrasting fluorescent color markers revealed dissociation features in their extravascular penetration. The albumin indicator spreads, as a rule, more extensively. 5. Differences in extent of penetration were also observed when fluorescent albumin or sodium fluorescein was concurrently used with radioactive inulin or sucrose. 6. A pronounced inhibition of C14 methyl-O-glucose brain uptake was observed on the side of a slight mercurial blood-brain barrier damage, which otherwise failed to produce any abnormal penetration of sodium fluorescein. 7. The features of selective vulnerability of the blood-brain barrier are discussed with regard to possible mechanisms involved.

Hydroxyl radical-scavenging property of secoisolariciresinol diglucoside (SDG) isolated from flax-seed

Abstract: Recently there has been a moderate resurgence in the use of flax-seed in a variety of ways including bread The scientific basis of its use is very limited There is some claim for beneficial effects in cancer and lupus nephritis These claims could be due to its ability to scavenge oxygen radicals However, its antioxidant activity is not known Recently a method has been developed to isolate secoisolariciresinol diglucoside (SDG) from defatted flax-seed in large quantity (patent pending) We investigated the ability of SDG to scavenge OH using high pressure liquid chromatography (HPLC) method OH was generated by photolysis of H2O2 (125-100 mumoles/ml) with ultraviolet light and was trapped with salicylic acid which is hydroxylated to produce OH-adduct products 2,3-dihydroxybenzoic acid (DHBA) and 2,5-DHBA H2O2 produced a concentration-dependent OH as estimated by 2,3-DHBA and 2,5-DHBA A standard curve was constructed for known concentrations of 2,3-DHBA and 2,5-DHBA against corresponding area under the peaks which then was used for measurement of 2,3-DHBA and 2,5-DHBA generated by UV irradiation of H2O2 in the presence of salicylic acid SDG in the concentration range of 25, 50, 100, 250, 500, 750, 1000 and 2000 micrograms/ml (364, 728, 1456, 3640, 7280, 10920, 14560 and 29120 microM respectively) produced a concentration-dependent decrease in the formation of 2,3-DHBA and 2,5-DHBA, the inhibition being 4 and 465% respectively with 25 micrograms/ml (364 microM) and 82 and 74% respectively with 2000 micrograms/ml (29120 microM) The decrease in OH-adduct products was due to scavenging of OH and not by scavenging of formed 2,3-DHBA and 2,5-DHBA SDG prevented the lipid peroxidation of liver homogenate in a concentration-dependent manner in the concentration range from 3193-25544 microM These results suggest that SDG scavenges OH and therefore has an antioxidant activity