Anti-Bacterial Agents ; Humans ; Mouth Diseases ; therapy ; Photochemistry ; Titanium ; pharmacology

Glutaraldehyde clinically is the most commonly accepted crosslinking reagent for bioprosthetic valves preparation. Glutaraldehyde-treated tissue is stable against chemical and enzymatic degradation; however, its calcification and cytotoxicity are severe. Dye-mediated photooxidation is an alternative tissue preservation method that oxidizes the protein with visible light in the presence of a suitable photosensitizer. This article reviews chemical mechanism, research progress, clinical applications future development of these two methods.
Animals ; Bioprosthesis ; Calcinosis ; Cross-Linking Reagents ; Glutaral ; Heart Valve Prosthesis ; Heart Valve Prosthesis Implantation ; Humans ; Photochemistry

A new method of using photoactivable ester with azido group was described to immobilize urease on polyether sulfone(PES) film surface. The effects of photoactive enzyme concentration, temperature, pH, irradiation time on the activity of immobilized urease were investigated. Reused times and storage stability were also studied. The results showed that the surface concentration of urease immobilized on PES surface was about 0.33 mg/cm2. When the irradiation time was 5 minutes, the relative activity of immobilized urease was the highest and the activity increased with the increase of the concentration of photoactive urease solution. The optimum pH and temperature of immobilized urease were 7 and 50 degrees C respectively. The relative activity of immobilized urease was stable (50%) after 12 times reused at 50 degrees C.
Enzyme Stability ; Enzymes, Immobilized ; metabolism ; radiation effects ; Membranes, Artificial ; Photochemistry ; Polymers ; Sulfones ; Urease ; metabolism ; radiation effects

OBJECTIVETo develop and evaluate the efficiency of air purification and sterilization instrument based on nano-sized TiO(2) photocatalytic technique.

METHODSThe nano-sized TiO(2) photocatalytic air purification and sterilization instrument was designed and a sample had been prepared. The sterilization efficiencies for E.coli and Klebsiella by the nano-sized TiO(2) photocatalytic instrument and ultraviolet (UV) were measured in closed labs. The on-site efficiency of the instrument was evaluated, too.

RESULTSThe nano-sized TiO(2) photocatalytic air purification and sterilization instrument was composed of five units: rough filter, nano-sized TiO(2) photocatalytic unit, activated carbon fiber filter, negative ion generator, and programmed control unit. The E.coli killing rates by the nano-sized TiO(2) photocatalytic instrument were 76.0%, 81.8%, 77.5%, and 80.7% at 30, 60, 90, and 120 minutes, respectively. There was no significant difference between the E.coli killing rates of the instrument and UV (P > 0.05), except the 120 minutes timepoint. The Klebsiella killing rates by the instrument were 78.4%, 79.5%, 67.3%, and 58.5% at 30, 60, 90, and 120 minutes, respectively. The Klebsiella killing efficiencies of the instrument at 30 and 60 minutes were better than that of UV (P < 0.01). There was no significant difference between the Klebsiella killing efficiencies of the instrument and UV (P > 0.05).

CONCLUSIONThe air sterilization efficiency of the nano-sized TiO(2) photocatalytic instrument should be equivalent or better as compared with the UV. This instrument might be used for the air purification and sterilization of the public locations.

Air Pollution ; prevention & control ; Decontamination ; methods ; Disinfection ; methods ; Nanostructures ; Photochemistry ; Titanium

This study was aimed to evaluate the efficacy of riboflavin photochemical inactivation of virus in red blood cells by using animal models. human cytomegalovirus (HCMV) plus red blood cells were used as indicator, 30 BALA/c mice were divided into the experimental group (n = 10), virus control group (n = 10), visible light control group (n = 5) and red blood cell control group (n = 5). Mice in experimental group were inoculated with red blood cells inactive by the riboflavin photochemical, mice in virus control group was injected with red blood cells without riboflavin photochemical inactivation treatment, and mice in light control group was infused with red blood cells irradiated by visible light, and mice in red blood cells control group was injected with normal red blood cells. The virus was isolated in vitro from mice of various groups, the HCMV UL83 gene was detected by PCR, the PP65 antigen was identified by indirect immunofluorescence. The results indicated that the virus isolation, PCR detection and indirect immunofluorescence identification all showed positive in virus control group and visible light control group, while the results of detection in experimental and red blood cell control groups were negative. It is concluded that riboflavin photochemical viral inactivation of red blood cells is effective.
Animals ; Erythrocytes ; virology ; Humans ; Mice ; Mice, Inbred BALB C ; Models, Animal ; Photochemistry ; Riboflavin ; pharmacology ; Virus Inactivation

Tumor Necrosis Factor is one of the cell factors with much stronger anti-tumor activity. In this study, photoactive arylazide-4-azidobenzoic acid was modified to Tumor Necrosis Factor-alpha (TNF-alpha). The IR data (2127cm(-1)) was given to confirm the modification. By photo-immobilization, this modified TNF-a was immobilized on cell culture polystyrene. Both the relation between the amount of TNF-alpha in feed and immobilized TNF-alpha and the influence of different UV irradiation time on photo-immobilization are discussed. Microscopic observations of the photo-immobilization TNF-alpha were made by use of scanning electrom microscope and atomic force microscope.
Female ; Humans ; Photochemistry ; Tumor Necrosis Factor-alpha ; chemistry ; therapeutic use ; Ultraviolet Rays ; Uterine Cervical Neoplasms ; therapy

It is important to research the rules about accumulation and distribution of arsenic and cadmium by tea plants, which will give us some scientific ideas about how to control the contents of arsenic and cadmium in tea. In this study, by field investigation and pot trial, we found that mobility of arsenic and cadmium in tea plants was low. Most arsenic and cadmium absorbed were fixed in feeding roots and only small amount was transported to the above-ground parts. Distribution of arsenic and cadmium, based on their concentrations of unit dry matter, in tea plants grown on un-contaminated soil was in the order: feeding roots>stems approximately main roots>old leaves>young leaves. When tea plants were grown on polluted soils simulated by adding salts of these two metals, feeding roots possibly acted as a buffer and defense, and arsenic and cadmium were transported less to the above-ground parts. The concentration of cadmium in soil significantly and negatively correlated with chlorophyll content, photosynthetic rate, transpiration rate and biomass production of tea plants.
Arsenic ; metabolism ; Biomass ; Cadmium ; metabolism ; Camellia sinensis ; metabolism ; Chlorophyll ; metabolism ; Photochemistry ; Plant Shoots ; metabolism ; Tea ; metabolism

OBJECTIVETo investigate the photocatalytic degradation of gaseous ammonia in static state by using nano-TiO2 as photocatalyst supported on latex paint film under UV-irradiation.

METHODSExperiments were conducted to study the relationship between the initial concentration of ammonia and the degradation products competing to be adsorbed on catalyst surface. Degradation of ammonia and its products were detected by spectrophotometry and catalytic kinetic spectrophotometry, respectively.

RESULTSOn the one hand, TiO2 catalyst was excellent for degradation of ammonia, and the crystal phase of TiO2, anatase or rutile, had little effect on degradation of ammonia, but the conversion of ammonia grew with the increase of catalyst content. On the other hand, apparent rate constant and conversion of ammonia decreased with the increase of initial concentration of ammonia, and the photocatalytic degradation reaction followed a pseudo-first-order expression due to the evidence of linear correlation between -lnC/C0 vs. irradiation time t, but the relationship between initial concentration and the degradation products was not linear in low initial concentration.

CONCLUSIONWhether the photocatalytic degradation of ammonia in static state follows a first-order reaction depends on the initial ammonia concentration due to competition in adsorption between reactant and the degradation products.

Ammonia ; chemistry ; Catalysis ; Gases ; Kinetics ; Metal Nanoparticles ; Microscopy, Electron, Transmission ; Paint ; Photochemistry ; Titanium ; chemistry

The aim of this study was to investigate the immune regulatory effect of dendritic cells phagocytosing photochemotherapy-treated allogeneic spleen lymphocytes on syngeneic T cells. DA rat spleen lymphocytes were treated with 8-methoxypsoralen plus UVA irradiation (PUVA). LEW rat bone marrow-derived DCs were co-cultured with PUVA-treated DA spleen lymphocytes (PUVA-SP), and the surface markers (MHC-II, CD86 and CD40) of treated DC were detected by flow cytometry. CFSE-labeled PUVA SP were incubated with LEW DCs and the phagocytosis of DCs on PUVA-SP was observed by using fluorescent microscope. The ability of DC phagocytosing allogeneic PUVA-SP (PUVA-SP DC) to stimulate the proliferation of LEW T cells was analyzed by mixed leukocyte reactions (MLR). The production of IL-4, IL-10, IL-2, IFN-gamma in MLR culture supernatant was determined by luminex method. The results indicated that the PUVA treatment effectively induced early apoptosis of DA rat spleen lymphocytes. After co-culture, DC efficiently phagocytosed allogeneic PUVA-SP and still maintained an immature phenotype with low levels of MHC II, CD40 and CD86. PUVA-SP DC induced LEW T cell hyporesponsiveness to DA rat antigen, and led to skewing of T cell cytokine expression toward Th2 (IL-10 and IL-4). It is concluded that the PUVA-SP DC effectively down-regulate T cell response to alloantigen and induce Th2 immune deviation in vitro.
Animals ; Dendritic Cells ; cytology ; immunology ; physiology ; Flow Cytometry ; Isoantigens ; Phagocytosis ; immunology ; Photochemistry ; Rats ; Rats, Inbred Lew ; T-Lymphocytes ; immunology

Global warming caused by the increasing CO2 concentration in atmosphere is a serious problem in the international political, economic, scientific and environmental fields in recent years. Intensive carbon dioxide capture and storage (CCS) technologies have been developed for a feasible system to remove CO2 from industrial exhaust gases especially for combustion flue gas. In these technologies, the biofixation of CO2 by microalgae has the potential to diminish CO2 and produce the biomass. In this review, the current status focusing on biofixation of CO2 from combustion flue gases by microalgae including the selection of microalgal species and effect of flue gas conditions, the development of high efficient photobioreactor and the application of microalgae and its biomass product were reviewed and summarized. Finally, the perspectives of the technology were also discussed.
Air Pollutants ; isolation & purification ; metabolism ; Air Pollution ; prevention & control ; Biodegradation, Environmental ; Carbon Dioxide ; isolation & purification ; metabolism ; Microalgae ; metabolism ; Photochemistry