Correlation of fluorescence and photocatalytic activity of co-doped Tio2

Co-doped TiO2 (0.5-4 mol%) photocatalysts were synthesized via sol-gel method and their physical and chemical properties were investigated. Addition of Co oxides dopants induced anatase to rutile phase transition and reduced the band gap energy of TiO2. The fluorescence result indicated that the electron-hole recombination rate was reduced with the presence of Co oxides dopant. The best photocatalyst obtained was 3Co-TiO2 which enhanced the photocatalytic activity of TiO2 by 10 folds to 26.6%. The importance of fluorescence properties of Co-doped TiO2 towards its photodegradation of Congo Red was presented

Comparison of domiciliary oxygen using liquid oxygen and concentrator in northern Taiwan

Background/PurposeLong-term oxygen therapy has become standard treatment for patients with chronic respiratory insufficiency. However, patterns of long-term home oxygen therapy have not been well studied in Taiwan. Oxygen concentrator systems are commonly used in Taiwan, but liquid oxygen delivery systems are portable and may provide advantages over the concentrator system. This study compared oxygen usage between patients from a liquid oxygen group (LOG) and an oxygen concentrator group (OCG). The authors also assessed the physiologic responses of patients with chronic obstructive pulmonary disease (COPD) to ambulatory oxygen use at home.MethodsThe study used a retrospective, cross-sectional, observational survey design. The LOG comprised 42 patients, and the OCG comprised 102 patients. We recruited participants in northern Taiwan from July 2009 to April 2010. The questionnaire instruments that were used to collect data consisted of three parts: demographic characteristics, devices used in respiratory care, and activity status with portable oxygen. Two-minute walking tests were performed on COPD patients in their homes.ResultsCOPD was the most common diagnosis in our study, with more than 50% of patients who received oxygen long term in both groups having received this diagnosis. The LOG used oxygen for an average of 21.7 hours per day, whereas OCG averaged 15.2 hours per day (p<0.001). In the OCG, 92.2% of patients used a concentrator alone, whereas 23.8% of the LOG used liquid oxygen alone (p<0.001). The LOG patients were involved in significantly more outdoors activities (p=0.002) and reported traveling with oxygen more often (p<0.001) than the OCG patients. For patients with the same dyspnea level of COPD severity, those using liquid oxygen had a lower increase in pulse rate after the walking test, in comparison with the concentrator users.ConclusionPatients in the LOG used oxygen for longer hours, went on more outings, and were more likely to travel with oxygen than patients in the OCG. Being ambulatory with liquid oxygen might enable patients with COPD to walk more effectively

Photodegradation of Malachite Green by Immobilization of Titanium Dioxide on Glass Plates

The effects of pH, contact time, initial dye concentration, numbers of dip coating, light sources and repetitive usage of dip-coated TiO2 were studied in batch experiments in order to investigate the photodegradation efficiency of malachite green in aqueous solution by using titanium dioxide, TiO2 immobilized on glass plates. The photodegradation of malachite green was found to be more effective at lower initial dye concentration. Kinetic studies showed good correlation coefficient for a pseudo-first order kinetic model. The removal of malachite green was dependent on the TiO2 loading where the percentage removal of malachite green was 92.15, 94.28 and 98.43 % for 5, 10 and 15 number of TiO2 dip-coating, respectively. Among the three light sources used, sunlight possessed the highest removal efficiency with 100 % of removal of dye in 6 h of irradiation. The degradation of malachite green was enhanced in basic solution compared with acidic solution due to the amphoteric property of TiO2. The decolourization efficiency was found to be decreased after each repetitive usage of dip-coated TiO2 glass plates. However, the immobilized TiO2 still displayed a good performance in the removal of malachite green.

XRCC1, but not APE1 and hOGG1 gene polymorphisms is a risk factor for pterygium.

PurposeEpidemiological evidence suggests that UV irradiation plays an important role in pterygium pathogenesis. UV irradiation can produce a wide range of DNA damage. The base excision repair (BER) pathway is considered the most important pathway involved in the repair of radiation-induced DNA damage. Based on previous studies, single-nucleotide polymorphisms (SNPs) in 8-oxoguanine glycosylase-1 (OGG1), X-ray repair cross-complementing-1 (XRCC1), and AP-endonuclease-1 (APE1) genes in the BER pathway have been found to affect the individual sensitivity to radiation exposure and induction of DNA damage. Therefore, we hypothesize that the genetic polymorphisms of these repair genes increase the risk of pterygium.MethodsXRCC1, APE1, and hOGG1 polymorphisms were studied using fluorescence-labeled Taq Man probes on 83 pterygial specimens and 206 normal controls.ResultsThere was a significant difference between the case and control groups in the XRCC1 genotype (p=0.038) but not in hOGG1 (p=0.383) and APE1 (p=0.898). The odds ratio of the XRCC1 A/G polymorphism was 2.592 (95% CI=1.225-5.484, p=0.013) and the G/G polymorphism was 1.212 (95% CI=0.914-1.607), compared to the A/A wild-type genotype. Moreover, individuals who carried at least one C-allele (A/G and G/G) had a 1.710 fold increased risk of developing pterygium compared to those who carried the A/A wild type genotype (OR=1.710; 95% CI: 1.015-2.882, p=0.044). The hOGG1 and APE1 polymorphisms did not have an increased odds ratio compared with the wild type.ConclusionsXRCC1 (Arg399 Glu) is correlated with pterygium and might become a potential marker for the prediction of pterygium susceptibility

Nonsteroidal Anti-Inflammatory Drugs for Wounds: Pain Relief or Excessive Scar Formation?

The inflammatory process has direct effects on normal and abnormal wound healing. Hypertrophic scar formation is an aberrant form of wound healing and is an indication of an exaggerated function of fibroblasts and excess accumulation of extracellular matrix during wound healing. Two cytokines—transforming growth factor-β (TGF-β) and prostaglandin E2 (PGE2)—are lipid mediators of inflammation involving wound healing. Overproduction of TGF-β and suppression of PGE2 are found in excessive wound scarring compared with normal wound healing. Nonsteroidal anti-inflammatory drugs (NSAIDs) or their selective cyclooxygenase-2 (COX-2) inhibitors are frequently used as a pain-killer. However, both NSAIDs and COX-2 inhibitors inhibit PGE2 production, which might exacerbate excessive scar formation, especially when used during the later proliferative phase. Therefore, a balance between cytokines and medication in the pathogenesis of wound healing is needed. This report is a literature review pertaining to wound healing and is focused on TGF-β and PGE2

Expression of c-Kit, Flk-1, and Flk-2 Receptors in Benign and Malignant Tumors of Follicular Epithelial Origin

BackgroundVascular endothelial growth factor (VEGF) is a key regulator of physiologic as well as pathologic angiogenesis. The response of VEGF to endothelial cell mitogenesis and survival, as well as angiogenesis and microvascular permeability, is mainly mediated through its receptor-2, VEGFR2 (kinase domain receptor or fetal liver kinase-1, KDR or Flk-1). This study aimed to detect the expression of VEGFR2 in various forms of thyroid tumors. In addition, the expression of Flk-2 (receptor for Flt-3) and c-Kit (receptor for steel locus factor), which shows strong similarity to Flk-1, was also examined in thyroid tumors.MethodsRT-PCR analyses of c-Kit and immunohistochemical staining of c-Kit, Flk-1, and Flk-2 were performed in archived samples of 18 papillary thyroid carcinoma (PTC), 9 follicular thyroid carcinoma (FTC), 12 follicular adenoma (FA), and 7 nodular goiter (NG) samples. The data were correlated to clinicopathologic features.ResultsBy RT-PCR analyses, c-Kit expression was detected in 22% (4/18) of PTC, 22% (2/9) of FTC, 25% (3/12) of FA, and 57% (4/7) of NG samples. However, positive immunostaining signals of c-Kit were only observed in 17% (3/18) of PTC samples, and not in the others. Similarly, Flk-1 expression was only detected by immunohistochemistry in 67% (12/18) of PTC and 43% (3/7) of NG samples, and not in the others. Interestingly, the expression of Flk-2 was found in 89% (16/18) of PTC, 89% (8/9) of FTC, 75% (9/12) of FA, and 29% (2/7) of NG samples. An inverse relationship of thyroid cancer size with Flk-2 expression was found.ConclusionFlk-2 expression was detected in various forms of thyroid tumors and increased Flk-2 expression was correlated with thyroid tumors with increased transforming activity, suggesting that Flk-2 is involved in pathogenic development of thyroid malignancy. Similarly, Flk-1 expression was also found in some thyroid tumors, while the expression of c-Kit-mediated pathways may not play a major role in thyroid tumorigenesis

Targeted profiling of chlorinated transformation products and the parent micropollutants in the aquatic environment: A comparison between two coastal cities

This study investigated chlorinated transformation products (TPs) and their parent micropollutants, aromatic pharmaceuticals and personal care products (PPCPs) in the urban water bodies of two metropolitan cities. Nine PPCPs and 16 TPs were quantitatively or semi-quantitatively determined using isotope dilution techniques and liquid chromatography-tandem mass spectrometry. TPs and most PPCPs were effectively removed by conventional wastewater treatments in a wastewater treatment plant (WWTP). Chlorinated parabens and all PPCPs (at concentrations below 1000 ng/L) were present in the waters receiving treated wastewater. By contrast, the waters receiving untreated wastewater contained higher levels of PPCPs (up to 9400 ng/L) and more species of chlorinated TPs including chlorinated parabens, triclosan, diclofenac, and bisphenol A. The very different chemical profiles between the water bodies of the two cities of similar geographical and climatic properties may be attributed to their respective uses of chemicals and policies of wastewater management. No apparent increase in the number of species or abundances of TPs was observed in either the chlorinated wastewater or the seawater rich in halogens. This is the first study to elucidate and compare the profiles of multiple TPs and their parent PPCPs in the water bodies of coastal cities from tropical islands. Our findings suggest that chlorinated derivatives of bisphenol A, diclofenac, triclosan, and parabens in the surface water originate from sources other than wastewater disinfection or marine chlorination. Although further studies are needed to identify the origins, conventional wastewater treatments may protect natural water bodies against contamination by those chlorinated substances