Displaying publications 101 - 120 of 142 in total

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  1. Huwaidi A, Pathak N, Syahir A, Ikeno S
    Biochem Biophys Res Commun, 2018 09 05;503(2):910-914.
    PMID: 29928878 DOI: 10.1016/j.bbrc.2018.06.095
    Ultraviolet (UV) radiation causes damage in all living organisms, including DNA damage that leads to cell death. Herein, we provide a new technique for UV radiation protection through intracellular short peptide expression. The late embryogenesis abundant (LEA) peptide, which functions as a shield that protects macromolecules from various abiotic stress, was obtained from the Polypedilum vanderplanki group 3 LEA protein. Recombinant Escherichia coli BL21 (DE3) expressing functional LEA short peptide in vivo were exposed to UVA and UVC radiation for 4, 6, and 8 h. E. coli transformants expressing the LEA peptide showed higher cell viability under both UVA and UVC treatment at all time points as compared with that of the control. Furthermore, the cells expressing LEA peptide showed a higher number of colony-forming units per dilution under UVA and UVC treatment. These results suggested that expression of the short peptide could be useful for the development of genetically modified organisms and in applications that require resilience of organisms to UV radiation.
    Matched MeSH terms: Ultraviolet Rays*
  2. Megat Nabil Mohsin S, Hussein MZ, Sarijo SH, Fakurazi S, Arulselvan P, Taufiq-Yap YH
    Int J Nanomedicine, 2018;13:6359-6374.
    PMID: 30349255 DOI: 10.2147/IJN.S171390
    Introduction: The potential of layered double hydroxide (LDH) as a host of multiple ultraviolet-ray absorbers was investigated by simultaneous intercalation of benzophenone 4 (B4) and Eusolex® 232 (EUS) in Zn/Al LDH.

    Methods: The nanocomposites were prepared via coprecipitation method at various molar ratios of B4 and EUS.

    Results: At equal molar ratios, the obtained nanocomposite showed an intercalation selectivity that is preferential to EUS. However, the selectivity ratio of intercalated anions was shown to be capable of being altered by adjusting the molar ratio of intended guests during synthesis. Dual-guest nanocomposite synthesized with B4:EUS molar ratio 3:1 (ZEB [3:1]) showed an intercalation selectivity ratio of B4:EUS =53:47. Properties of ZEB (3:1) were monitored using powder X-ray diffractometer to show a basal spacing of 21.8 Å. Direct-injection mass spectra, Fourier transform infrared spectra, and ultraviolet-visible spectra confirmed the dual intercalation of both anions into the interlayer regions of dual-guest nanocomposite. The cytotoxicity study of dual-guest nanocomposite ZEB (3:1) on human dermal fibroblast cells showed no significant toxicity until 25 μg/mL.

    Conclusion: Overall, the findings demonstrate successful customization of ultraviolet-ray absorbers composition in LDH host.

    Matched MeSH terms: Ultraviolet Rays*
  3. Mansor NA, Tay KS
    Environ Sci Pollut Res Int, 2017 Oct;24(28):22361-22370.
    PMID: 28801887 DOI: 10.1007/s11356-017-9892-6
    This study investigated the reaction kinetics and mechanism of the degradation of 5,5-diphenylhydantoin (DPH) during conventional chlorination and UV/chlorination. DPH is one of the antiepileptic drugs, which has frequently been detected in the aquatic environment. For chlorination, the second-order rate constant for the reaction between DPH and free active chlorine (FAC) was determined at pH 5 to 8. At pH 6 to 8, the efficiency of chlorination in the removal of DPH was found to be dominated by the reaction involving hypochlorous acid (HOCl). The result also showed that anionic species of DPH was more reactive toward FAC as compared with neutral DPH. For UV/chlorination, the effect of FAC dosage and pH on the degradation of DPH was evaluated. UV/chlorination is a more effective method for removing DPH as compared with conventional chlorination and UV irradiation. The DPH degradation rate was found to increase with increasing FAC concentration. On the other hand, the degradation of DPH was found to be more favorable under the acidic condition. Based on the identified transformation by-products, DPH was found to be degraded through the reaction at imidazolidine-2,4-dione moiety of DPH for both chlorination and UV/chlorination. Toxicity study on the chlorination and UV/chlorination-treated DPH solutions suggested that UV/chlorination is a more efficient method for reducing the toxicity of DPH.
    Matched MeSH terms: Ultraviolet Rays*
  4. Al-Naggar RA, Al-Naggar TH, Bobryshev YV
    Asian Pac J Cancer Prev, 2011;12(4):995-9.
    PMID: 21790240
    INTRODUCTION: Malignant melanoma in particular is one of the few remaining cancers with an increasing incidence.

    OBJECTIVES: The objective of this study is to explore the perceptions and opinions of young Malaysians towards skin cancer prevention.

    METHODOLOGY: Focus group discussions were conducted among 33 medical science students from Management and Science University (MSU), Shah Alam, Malaysia, using convenience sampling. Students were divided into 4 focus groups consisting of 8, 8, 9 and 8 students respectively. The facilitator wrote down the conversations and data obtained were classified into various categories and analyzed manually.

    RESULTS: The majority of the participants mentioned that overexposure to ultraviolet light is the commonest cause of skin cancer but also that the most benefit we get from sun ight is vitamin D synthesis. The majority mentioned that the best prevention measure for skin cancer is using a sunscreen, followed by limit exposure to the sun.

    CONCLUSION: The present study demonstrated there is a lack of knowledge regarding screening methods and prevention measures of skin cancer. Therefore, there is a need to establish health education unit in all universities to educate all university students regarding various health problems including skin cancer prevention.
    Matched MeSH terms: Ultraviolet Rays/adverse effects
  5. Ashraf MA, Peng WX, Fakhri A, Hosseini M, Kamyab H, Chelliapan S
    J. Photochem. Photobiol. B, Biol., 2019 Sep;198:111579.
    PMID: 31401316 DOI: 10.1016/j.jphotobiol.2019.111579
    The sol-gel/ultrasonically rout produced the novel MnS2-SiO2 nano-hetero-photocatalysts with the various ratio of MnS2. Prepared nano-catalyst were investigated in the photo-degradation of methylene blue under UV light illumination. Structural and optical attributes of as-prepared nano-catalysts were evaluated by X-ray diffraction and photoelectron spectroscopy. The morphological were studied by scanning electron microscopy-EDS, and dynamic light scattering. The diffuse reflectance spectroscopy was applied to examine the band gap energy. The Eg values of SiO2, MnS2-SiO2-0, MnS2-SiO2-1, and MnS2-SiO2-2 nanocomposites are 6.51, 3.85, 3.17, and 2.67 eV, respectively. The particle size of the SiO2 and MnS2-SiO2-1 nanocomposites were 100.0, and 65.0 nm, respectively. The crystallite size values of MnS2-SiO2-1 were 52.21 nm, and 2.9 eV, respectively. MnS2-SiO2 nano-photocatalyst was recognized as the optimum sample by degrading 96.1% of methylene blue from water. Moreover, the influence of pH of the solution, and contact time as decisive factors on the photo-degradation activity were investigated in this project. The optimum data for pH and time were found 9 and 60 min, respectively. The photo-degradation capacity of MnS2-SiO2-2 is improved (96.1%) due to the low band gap was found from UV-vis DRS. The antimicrobial data of MnS2-SiO2 were studied and demonstrated that the MnS2-SiO2 has fungicidal and bactericidal attributes.
    Matched MeSH terms: Ultraviolet Rays*
  6. Ramli R, Che Man Z, Nordin R, Abdul Karim F, Rashdi MF, Oxley J, et al.
    Traffic Inj Prev, 2016 Sep;17 Suppl 1:79-85.
    PMID: 27586107 DOI: 10.1080/15389588.2016.1203428
    OBJECTIVE: Vietnamese spend hours travelling on the road using their motorcycles. Their helmets are exposed continuously to sunlight and rain. The objectives of this study were to determine the association between the effect of photo-oxidative degradation (POD) of the outer shells and helmet age on helmet damage. The micro-structural change of the outer shell was also investigated.

    METHODS: This was a prospective, cross sectional study recruiting injured motorcyclists from Hanoi, Vietnam hospital. The participants were interviewed by a trained researcher. The participants' helmets were collected post-crash. Initially, the helmets were examined for their type and external characteristics. A 3 cm × 3 cm cut was made on the helmet in the impacted and non-impacted areas (control). These areas were investigated for evidence of POD and presence of micro-cracks and material disintegration. 50 participants were enrolled. Sources of information included questionnaire and laboratory analyses. The helmet factors of interest were age of the helmet, exposure of helmet to sunlight and rain (duration/day) and history of previous impact. Laboratory analyses included Fourier Transform Infra Red (FTIR) for degradation and scanning electron microscopy (SEM) for micro-structural examination.

    RESULTS: Majority of the helmets was the open-face type, 40 (80.0%). 31 (62.0%) helmets aged less than three years (LTY) and 19 (38.0%) were three years old or more (MTY). 19 (61.3%) of the LTY helmets and 12 (63.2%) MTY helmets showed evidence of POD. The duration of helmet exposure to sunlight was between 93 to 6570 hours (mean 2347.74 hours; SD 1733.39). The SEM showed 15 helmets (30%) with micro-fractures, 21 helmets (42.0%) with material disintegration. Prolonged uv exposure to the ABS helmets resulted in changes in the helmet material in the form of material disintegration and microcracks and this association was statistically significant (p = 0.03).

    CONCLUSION: POD occurs due to routine exposure to the ultraviolet light. Prolonged uv exposure affects outer shell surface material integrity.

    Matched MeSH terms: Ultraviolet Rays/adverse effects*
  7. Alafiatayo AA, Lai KS, Ahmad S, Mahmood M, Shaharuddin NA
    Genomics, 2020 01;112(1):484-493.
    PMID: 30946891 DOI: 10.1016/j.ygeno.2019.03.011
    Exposing the skin to solar UV radiation induces cascades of signaling pathways and biological alterations such as redox imbalance, suppression of antioxidant genes and programmed cell death. Therefore, the aim of this study was to use RNA-Seq to unravel the effects of UV radiation on Normal Human Adult Fibroblast cells (NHDF). Cells were exposed to UV (20 mJ/cm2 for 3 mins) and incubated for 24 h. Total mRNA from the cells generated libraries of 72,080,648 and 40,750,939 raw reads from UV-treated and control cells respectively. Of the differentially expressed genes (DEGs) produced 2,007 were up-regulated and 2,791 were down-regulated (fold change ≥2, p 
    Matched MeSH terms: Ultraviolet Rays*
  8. Liu X, Zhang R, Shi H, Li X, Li Y, Taha A, et al.
    Mol Med Rep, 2018 05;17(5):7227-7237.
    PMID: 29568864 DOI: 10.3892/mmr.2018.8791
    Ultraviolet (UV) radiation induces DNA damage, oxidative stress, and inflammatory processes in skin, resulting in photoaging. Natural botanicals have gained considerable attention due to their beneficial protection against the harmful effects of UV irradiation. The present study aimed to evaluate the ability of curcumin (Cur) to protect human dermal fibroblasts (HDFs) against ultraviolet A (UVA)‑induced photoaging. HDFs were treated with 0‑10 µM Cur for 2 h and subsequently exposed to various intensities of UVA irradiation. The cell viability and apoptotic rate of HDFs were investigated by MTT and flow cytometry assays, respectively. The effect of UVA and Cur on the formation of reactive oxygen species (ROS), malondialdehyde levels, which are an indicator of ROS, and the levels/activity of antioxidative defense proteins, including glutathione, superoxide dismutase and catalase, were evaluated using 2',7'-dichlorofluorescin diacetate and commercial assay kits. Furthermore, western blotting was performed to determine the levels of proteins associated with endoplasmic reticulum (ER) stress, the apoptotic pathway, inflammation and the collagen synthesis pathway. The results demonstrated that Cur reduced the accumulation of ROS and restored the activity of antioxidant defense enzymes, indicating that Cur minimized the damage induced by UVA irradiation in HDFs. Furthermore, western blot analysis demonstrated that Cur may attenuate UVA‑induced ER stress, inflammation and apoptotic signaling by downregulating the protein expression of glucose‑regulated protein 78, C/EBP‑homologous protein, nuclear factor‑κB and cleaved caspase‑3, while upregulating the expression of Bcl‑2. Additionally, it was demonstrated that Cur may regulate collagen metabolism by decreasing the protein expression of matrix metalloproteinase (MMP)‑1 and MMP‑3, and may promote the repair of cells damaged as a result of UVA irradiation through increasing the protein expression of transforming growth factor‑β (TGF‑β) and Smad2/3, and decreasing the expression of the TGF‑β inhibitor, Smad7. In conclusion, the results of the present study indicate the potential benefits of Cur for the protection of HDFs against UVA‑induced photoaging and highlight the potential for the application of Cur in skin photoprotection.
    Matched MeSH terms: Ultraviolet Rays/adverse effects*
  9. Ridhuan NS, Razak KA, Lockman Z, Abdul Aziz A
    PLoS One, 2012;7(11):e50405.
    PMID: 23189199 DOI: 10.1371/journal.pone.0050405
    In this study, zinc oxide (ZnO) nanorod arrays were synthesized using a simple hydrothermal reaction on ZnO seeds/n-silicon substrate. Several parameters were studied, including the heat-treatment temperature to produce ZnO seeds, zinc nitrate concentration, pH of hydrothermal reaction solution, and hydrothermal reaction time. The optimum heat-treatment temperature to produce uniform nanosized ZnO seeds was 400°C. The nanorod dimensions depended on the hydrothermal reaction parameters. The optimum hydrothermal reaction parameters to produce blunt tip-like nanorods (770 nm long and 80 nm in top diameter) were 0.1 M zinc nitrate, pH 7, and 4 h of growth duration. Phase analysis studies showed that all ZnO nanorods exhibited a strong (002) peak. Thus, the ZnO nanorods grew in a c-axis preferred orientation. A strong ultraviolet (UV) emission peak was observed for ZnO nanorods grown under optimized parameters with a low, deep-level emission peak, which indicated high optical property and crystallinity of the nanorods. The produced ZnO nanorods were also tested for their UV-sensing properties. All samples responded to UV light but with different sensing characteristics. Such different responses could be attributed to the high surface-to-volume ratio of the nanorods that correlated with the final ZnO nanorods morphology formed at different synthesis parameters. The sample grown using optimum synthesis parameters showed the highest responsivity of 0.024 A/W for UV light at 375 nm under a 3 V bias.
    Matched MeSH terms: Ultraviolet Rays
  10. Mousavi Z, Soofivand F, Esmaeili-Zare M, Salavati-Niasari M, Bagheri S
    Sci Rep, 2016 Feb 01;6:20071.
    PMID: 26832329 DOI: 10.1038/srep20071
    In this work, zinc chromite (ZnCr2O4) nanostructures have been synthesized through co-precipitation method. The effect of various parameters such as alkaline agent, pH value, and capping agent type was investigated on purity, particle size and morphology of samples. It was found that particle size and morphology of the products could be greatly influenced via these parameters. The synthesized products were characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), fourier transform infrared (FT-IR) spectra, X-ray energy dispersive spectroscopy (EDS), photoluminescence (PL) spectroscopy, diffuse reflectance spectroscopy (DRS) and vibrating sample magnetometry (VSM). The superhydrophilicity of the calcined oxides was investigated by wetting experiments and a sessile drop technique which carried out at room temperature in air to determine the surface and interfacial interactions. Furthermore, the photocatalytic activity of ZnCr2O4 nanoparticles was confirmed by degradation of anionic dyes such as Eosin-Y and phenol red under UV light irradiation. The obtained ZnCr2O4 nanoparticles exhibit a paramagnetic behavior although bulk ZnCr2O4 is antiferromagnetic, this change in magnetic property can be ascribed to finite size effects.
    Matched MeSH terms: Ultraviolet Rays
  11. Mengting Z, Kurniawan TA, Fei S, Ouyang T, Othman MHD, Rezakazemi M, et al.
    Environ Pollut, 2019 Dec;255(Pt 1):113182.
    PMID: 31541840 DOI: 10.1016/j.envpol.2019.113182
    Methylene blue (MB) is a dye pollutant commonly present in textile wastewater. We investigate and critically evaluate the applicability of BaTiO3/GO composite for photodegradation of MB in synthetic wastewater under UV-vis irradiation. To enhance its performance, the BaTiO3/GO composite is varied based on the BaTiO3 weight. To compare and evaluate any changes in their morphologies and crystalline structures before and after treatment, BET (Brunauer-Emmett-Teller), XRD (X-ray diffraction), FTIR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy) and TEM (transmission electron microscopy) tests are conducted, while the effects of reaction time, pH, dose of photocatalyst and initial MB concentration on its photodegradation by the composite are also investigated under identical conditions. The degradation pathways and removal mechanisms of MB by the BaTiO3/GO are elaborated. It is evident from this study that the BaTiO3/GO composite is promising for MB photodegradation through ·OH. Under optimized conditions (0.5 g/L of dose, pH 9.0, and 5 mg/L of MB concentration), the composite with 1:2 dose ratio of BaTiO3/GO has the highest MB degradation rate (95%) after 3 h of UV vis irradiation. However, its treated effluents still could not comply with the discharge standard limit of less than 0.2 mg/L imposed by national environmental legislation. This suggests that additional biological treatments are still required to deal with the remaining oxidation by-products of MB, still present in the wastewater samples such as 3,7-bis (dimethyl-amino)-10H-phenothiazine 5-oxide.
    Matched MeSH terms: Ultraviolet Rays
  12. Hasan HA, Abdulmalek E, Rahman MBA, Shaari KB, Yamin BM, Chan KW
    Chem Cent J, 2018 Dec 20;12(1):145.
    PMID: 30570683 DOI: 10.1186/s13065-018-0509-z
    BACKGROUND: Although the development of antibiotic and antioxidant manufacturing, the problem of bacterial resistance and food and/or cosmetics oxidation still needs more efforts to design new derivatives which can help to minimize these troubles. Benzimidazo[1,2-c]quinazolines are nitrogen-rich heterocyclic compounds that possess many pharmaceutical properties such as antimicrobial, anticonvulsant, immunoenhancer, and anticancer.

    RESULTS: A comparative study between two methods, (microwave-assisted and conventional heating approaches), was performed to synthesise a new quinazoline derivative from 2-(2-aminophenyl)-1H-benzimidazole and octanal to produce 6-heptyl-5,6-dihydrobenzo[4,5]imidazo[1,2-c]quinazoline (OCT). The compound was characterised using FTIR, 1H and 13C NMR, DIMS, as well as X-ray crystallography. The most significant peak in the 13C NMR spectrum is C-7 at 65.5 ppm which confirms the cyclisation process. Crystal structure analysis revealed that the molecule grows in the monoclinic crystal system P21/n space group and stabilised by an intermolecular hydrogen bond between the N1-H1A…N3 atoms. The crystal packing analysis showed that the molecule adopts zig-zag one dimensional chains. Fluorescence study of OCT revealed that it produces blue light when expose to UV-light and its' quantum yield equal to 26%. Antioxidant activity, which included DPPH· and ABTS·+ assays was also performed and statistical analysis was achieved via a paired T-test using Minitab 16 software with P 

    Matched MeSH terms: Ultraviolet Rays
  13. Zainudin MAM, Poojary MM, Jongberg S, Lund MN
    Food Chem, 2019 Nov 30;299:125132.
    PMID: 31299519 DOI: 10.1016/j.foodchem.2019.125132
    Protein oxidation of beef patties stored in high oxygen modified atmosphere packaging for 9 days was investigated. Meat was either stored in the dark, under light, or in the dark with addition of FeCl2/H2O2/myoglobin (forced oxidation). SDS-PAGE analysis showed high degree of protein polymerization for meat exposed to light, compared to the other samples. Light exposure induced reducible (disulfide) and non-reducible cross-links, while mainly disulfides were formed in meat stored in the dark. Light exposure was responsible for 58% loss of free thiols (Cys residues). No significant loss of other amino acid residues was observed and none of the most common oxidation products of tryptophan, tyrosine, and phenylalanine were detected. Intrinsic fluorescence measurements of tryptophan showed 27% loss in samples exposed to light, which was ascribed to loss of protein solubility via protein polymerization rather than tryptophan oxidation. Protein carbonyls were mainly detected in forced oxidized samples at Day 0.
    Matched MeSH terms: Ultraviolet Rays
  14. Low QJ, Teo KZ, Lim TH, Cheo SW, Yap WYE
    Med J Malaysia, 2021 03;76(2):212-217.
    PMID: 33742630
    INTRODUCTION: Excessive ultraviolet light (UV) can cause premature skin aging and potentially skin cancer. Currently there is a lack of awareness among health care professionals and the public on sun protection. The objectives of this study were to determine knowledge on sunscreen and skin cancer among health care professionals, to evaluate the knowledge, attitude, practice and perception of doctors and pharmacists toward the usage of sunscreen as protection against UV radiation.

    MATERIALS AND METHODS: This is a cross-sectional study conducted among doctors and pharmacists in Hospital Sultanah Nora Ismail, Batu Pahat, Johor, Malaysia. Questionnaires were used in this study.

    RESULTS: A total of 384 participants completed the questionnaires. The participants consisted of 323 doctors (84.1%) and 61 pharmacists (15.9%). The age group of the participants ranged between 25 till 55 years old. Ninety doctors (27.9%) and thirty-one pharmacists (51.0%) reported used sunscreen daily (p<0.001). This finding showed that there was a deficit in the practice of sun protection. Pharmacists scored a higher knowledge score of median 12 (IQR=3.0) while the doctors scored 11 (IQR=2.0). This study showed a significant association between ethnicity and skin cancer knowledge (p<0.05).

    CONCLUSION: This study demonstrated a lack of knowledge of sunscreen and skin cancer prevention among health care practitioners. This finding supports better medical education program on this topic.

    Matched MeSH terms: Ultraviolet Rays
  15. Hosseini M, Fazelian N, Fakhri A, Kamyab H, Yadav KK, Chelliapan S
    J. Photochem. Photobiol. B, Biol., 2019 May;194:128-134.
    PMID: 30953914 DOI: 10.1016/j.jphotobiol.2019.03.016
    NiS-SiO2 and Cr2S3-TiO2 synthesized by Ultrasound-Microwave method was tested for the photo-degradation of methyl red as azo dye under ultraviolet (UV) light. The structure and morphology of the synthesized materials were examined through scanning electron microscopy, X-ray diffraction and photoelectron spectroscopy, energy-dispersive spectroscopy, dynamic light scattering and the band gap energy differences were determined through diffuse reflectance spectroscopy (DRS). The crystallite size and band gap values of SiO2, TiO2, NiS-SiO2 and Cr2S3-TiO2-1 were obtained from XRD and UV-vis DRS analysis and found insignificant 44.22, 54.11, and 57.11 nm, and 8.9, 3.2, 3.0, 2.7 eV, respectively. The NiS-SiO2 and Cr2S3-TiO2 nanocomposites exhibited good stability and catalytic performance in the azo dye degradation; the composite provides a complete degradation after 50 min under UV irradiation. The effects of different quencher compounds on the Methyl red dye degradation were also investigated. The result for this experiment shows the system without the quencher was highly degradation of Methyl red. The antibacterial influence of the SiO2, TiO2, NiS-SiO2 and Cr2S3-TiO2-1 were studied versus two species bacteria. The antifungal performance of this nanoparticle was analyzed versus two species fungi as the C. albicans and P. funiculosum. Biological data demonstrated that the prepared catalyst has great bactericidal and fungicidal properties.
    Matched MeSH terms: Ultraviolet Rays
  16. Mohd Masri S, Nazni WA, Lee HL, T Rogayah TA, Subramaniam S
    Trop Biomed, 2005 Dec;22(2):185-9.
    PMID: 16883286 MyJurnal
    Three new techniques of sterilising maggots of Lucilia cuprina for the purpose of debriding intractable wounds were studied. These techniques were utilisation of ultra-violet C (UVC) and maggot sterilisation with disinfectants. The status of sterility was checked on nutrient agar and blood agar and confirmed with staining. The indicators for the effectiveness of the methods were sterility and survival rate of the eggs or larvae. Egg sterilisation with UVC had the lowest hatching rate (16+/-0.00%) while egg sterilisation with disinfectants showed high hatching rate (36.67+/-4.41%) but low maggot survival rate (31.67+/-1.67%). Sterilisation of the maggots was the most suitable, since the survival rate was the highest (88.67+/-0.88%). Complete sterility was achieved in all cases, except that Proteus mirabilis was consistently found. However, the presence of this microorganism was considered beneficial.
    Matched MeSH terms: Ultraviolet Rays
  17. Toopkanloo SP, Tan TB, Abas F, Azam M, Nehdi IA, Tan CP
    Molecules, 2020 Dec 11;25(24).
    PMID: 33322600 DOI: 10.3390/molecules25245873
    In order to improve the membrane lipophilicity and the affinity towards the environment of lipid bilayers, squalene (SQ) could be conjugated to phospholipids in the formation of liposomes. The effect of membrane composition and concentrations on the degradation of liposomes prepared via the extrusion method was investigated. Liposomes were prepared using a mixture of SQ, cholesterol (CH) and Tween80 (TW80). Based on the optimal conditions, liposome batches were prepared in the absence and presence of SQ. Their physicochemical and stability behavior were evaluated as a function of liposome constituent. From the optimization study, the liposomal formulation containing 5% (w/w) mixed soy lecithin (ML), 0.5% (w/w) SQ, 0.3% (w/w) CH and 0.75% (w/w) TW80 had optimal physicochemical properties and displayed a unilamellar structure. Liposome prepared using the optimal formulation had a low particle size (158.31 ± 2.96 nm) and acceptable %increase in the particle size (15.09% ± 3.76%) and %trolox equivalent antioxidant capacity (%TEAC) loss (35.69% ± 0.72%) against UV light treatment (280-320 nm) for 6 h. The interesting outcome of this research was the association of naturally occurring substance SQ for size reduction without the extra input of energy or mechanical procedures, and improvement of vesicle stability and antioxidant activity of ML-based liposome. This study also demonstrated that the presence of SQ in the membrane might increase the acyl chain dynamics and decrease the viscosity of the dispersion, thereby limiting long-term stability of the liposome.
    Matched MeSH terms: Ultraviolet Rays
  18. Melin AD, Wells K, Moritz GL, Kistler L, Orkin JD, Timm RM, et al.
    Mol Biol Evol, 2016 Apr;33(4):1029-41.
    PMID: 26739880 DOI: 10.1093/molbev/msv346
    Debate on the adaptive origins of primates has long focused on the functional ecology of the primate visual system. For example, it is hypothesized that variable expression of short- (SWS1) and middle-to-long-wavelength sensitive (M/LWS) opsins, which confer color vision, can be used to infer ancestral activity patterns and therefore selective ecological pressures. A problem with this approach is that opsin gene variation is incompletely known in the grandorder Euarchonta, that is, the orders Scandentia (treeshrews), Dermoptera (colugos), and Primates. The ancestral state of primate color vision is therefore uncertain. Here, we report on the genes (OPN1SW and OPN1LW) that encode SWS1 and M/LWS opsins in seven species of treeshrew, including the sole nocturnal scandentian Ptilocercus lowii. In addition, we examined the opsin genes of the Central American woolly opossum (Caluromys derbianus), an enduring ecological analogue in the debate on primate origins. Our results indicate: 1) retention of ultraviolet (UV) visual sensitivity in C. derbianus and a shift from UV to blue spectral sensitivities at the base of Euarchonta; 2) ancient pseudogenization of OPN1SW in the ancestors of P. lowii, but a signature of purifying selection in those of C. derbianus; and, 3) the absence of OPN1LW polymorphism among diurnal treeshrews. These findings suggest functional variation in the color vision of nocturnal mammals and a distinctive visual ecology of early primates, perhaps one that demanded greater spatial resolution under light levels that could support cone-mediated color discrimination.
    Matched MeSH terms: Ultraviolet Rays
  19. Vythalingam LM, Hossain MAM, Bhassu S
    Mol Cell Probes, 2021 02;55:101683.
    PMID: 33259896 DOI: 10.1016/j.mcp.2020.101683
    Invasive alien fish species have become a silent treat towards the ecosystem especially the native fish population in Malaysia. There has been a need to develop rapid identification methods that can aid management teams in identifying fish species that are not native to our ecosystem. Current visual identification methods are highly tedious and require time, delaying action towards curbing the invasion. The LAMP assay successfully identified six popular invasive fish species in Malaysia. None of the LAMP assays showed false positives and the Limit of Detection of the LAMP primers were highly sensitive and could detect DNA samples up to 1 × 10-15 ng/μl. The LAMP primers designed were highly specific to the target species and did not amplify non target species. DNA sequencing was done to ensure the accuracy of LAMP assay results. This study demonstrates that LAMP is a suitable tool in species identification efforts of invasive fish species in Malaysia.
    Matched MeSH terms: Ultraviolet Rays
  20. Ismail I, Gaskin S, Pisaniello D, Edwards JW
    Ind Health, 2018 Apr 07;56(2):166-170.
    PMID: 29199264 DOI: 10.2486/indhealth.2017-0157
    Elbow length PVC gloves are often recommended for protection against organophosphorus pesticide (OP) exposure in agriculture. However, performance may be reduced due to high temperature, UV exposure and abrasion. We sought to assess these impacts for two OPs under normal use and reasonable worst-case scenarios. Glove permeation tests were conducted using ASTM cells with two PVC glove brands at 23°C and 45°C for up to 8 h. Technical grade dichlorvos and formulated diazinon were used undiluted and at application strength. Breakthough of undiluted dichlorvos occurred at both 23°C and 45°C, but only at 45°C for application strength. Breakthrough of diazinon was not achieved, except when undiluted at 45°C. UV-exposed and abraded gloves showed reduced performance, with the effect being approximately two-fold for dichlorvos. Only small differences were noted between glove brands. Extra precautions should be taken when handling concentrated OPs at high temperature, or when using abraded or sunlight-exposed gloves.
    Matched MeSH terms: Ultraviolet Rays
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