Displaying publications 1 - 20 of 46 in total

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  1. p53 Status does not affect photodynamic cell killing induced by hypericin
    Lee HB, Ho AS, Teo SH
    Cancer Chemother Pharmacol, 2006 Jul;58(1):91-8.
    PMID: 16211395
    Given that p53 is a tumor suppressor that plays a central role in the cellular response to DNA damage and that more than 50% of all cancers have mutated p53, the wider utility of photodynamic therapy (PDT) in the treatment of cancer will depend on an understanding of whether p53 status modulates response to PDT. In this study, we investigated the photosensitivity of isogenic cell lines that differ only in their p53 status to PDT using hypericin as the photosensitizer.
    Matched MeSH terms: Photochemotherapy*
  2. Oral lichen planus and lichenoid reactions: etiopathogenesis, diagnosis, management and malignant transformation
    Ismail SB, Kumar SK, Zain RB
    J Oral Sci, 2007 Jun;49(2):89-106.
    PMID: 17634721
    Lichen planus, a chronic autoimmune, mucocutaneous disease affects the oral mucosa (oral lichen planus or OLP) besides the skin, genital mucosa, scalp and nails. An immune mediated pathogenesis is recognized in lichen planus although the exact etiology is unknown. The disease most commonly affects middle-aged females. Oral lichenoid reactions (OLR) which are considered variants of OLP, may be regarded as a disease by itself or as an exacerbation of an existing OLP, by the presence of medication (lichenoid drug reactions) or dental materials (contact hypersensitivity). OLP usually presents as white striations (Wickham's striae), white papules, white plaque, erythema, erosions or blisters. Diagnosis of OLP is established either by clinical examination only or by clinical examination with histopathologic confirmation. Direct immunofluorescence examination is only used as an adjunct to the above method of diagnosis and to rule out specific autoimmune diseases such as pemphigus and pemphigoid. Histopathologic features of OLP and OLR are similar with suggestions of certain discriminatory features by some authors. Topical corticosteroids are the treatment of choice for OLP although several other medications have been studied including retinoids, tacrolimus, cyclosporine and photodynamic therapy. Certain OLP undergo malignant transformation and the exact incidence and mechanisms are still controversial. In this paper, etiopathogenesis, diagnosis, management and malignant transformation of OLP and OLR have been reviewed.
    Matched MeSH terms: Photochemotherapy
  3. Light-activated cytotoxic compounds from Malaysian microorganisms for photodynamic therapy of cancer
    Kamal N, Sabaratnam V, Abdullah N, Ho AS, Teo SH, Lee HB
    Antonie Van Leeuwenhoek, 2009 Feb;95(2):179-88.
    PMID: 19125347 DOI: 10.1007/s10482-008-9301-8
    Photodynamic therapy (PDT) is a promising cancer treatment which involves activation of a photosensitizing drug with light to produce reactive oxygen species that kill tumors without causing damage to unirradiated normal tissues. To date, only Photofrin, Foscan and Levulan have been approved for clinical treatment of cancer. Tropical habitats such as those found in Malaysia are attractive sources of new therapeutic compounds as tremendous chemical diversity is found in a large number of plants, animals, marine- and micro-organisms. In our screening program for novel photosensitizers from nature, colorful strains of fungi (from Aspergillus and Penicillium genus) and bacteria (including actinomycetes and photosynthetic bacteria) were collected from various habitats in Peninsular Malaysia, such as coastal soil, peat soil, marine sponges and wastewater ponds. Methanolic extracts from a total of 85 different species were evaluated with a short-term cell viability assay for photo-cytotoxicity, where a promyelocytic leukemia cell-line, HL60 incubated with 20 microg/ml of extracts was irradiated with 9.6 J/cm(2) of a broad spectrum light. Two of these extracts, one from Rhodobacter sphaeroides (PBUM003) and one from Rhodopseudomonas palustris (PBUM001) showed moderate to strong photo-cytotoxicity. Subsequent bioassay guided isolation of the PBUM001 extract yielded known photosensitisers that are based on bacteriochlorophyll-a by comparing their molecular weight data, HPLC profiles and UV-vis absorption spectra with literature values, thereby demonstrating the validity of our screening approach.
    Matched MeSH terms: Photochemotherapy*
  4. Systematic analysis of in vitro photo-cytotoxic activity in extracts from terrestrial plants in Peninsula Malaysia for photodynamic therapy
    Ong CY, Ling SK, Ali RM, Chee CF, Samah ZA, Ho AS, et al.
    J. Photochem. Photobiol. B, Biol., 2009 Sep 4;96(3):216-22.
    PMID: 19647445 DOI: 10.1016/j.jphotobiol.2009.06.009
    One hundred and fifty-five extracts from 93 terrestrial species of plants in Peninsula Malaysia were screened for in vitro photo-cytotoxic activity by means of a cell viability test using a human leukaemia cell-line HL60. These plants which can be classified into 43 plant families are diverse in their type of vegetation and their natural habitat in the wild, and may therefore harbour equally diverse metabolites with potential pharmaceutical properties. Of these, 29 plants, namely three from each of the Clusiaceae, Leguminosae, Rutaceae and Verbenaceae families, two from the Piperaceae family and the remaining 15 are from Acanthaceae, Apocynaceae, Bignoniaceae, Celastraceae, Chrysobalanaceae, Irvingiaceae, Lauraceae, Lythraceae, Malvaceae, Meliaceae, Moraceae, Myristicaceae, Myrsinaceae, Olacaceae and Sapindaceae. Hibiscus cannabinus (Malvaceae), Ficus deltoidea (Moraceae), Maranthes corymbosa (Chrysobalanaceae), Micromelum sp., Micromelum minutum and Citrus hystrix (Rutaceae), Cryptocarya griffithiana (Lauraceae), Litchi chinensis (Sapindaceae), Scorodocarpus bornensis (Olacaceae), Kokoona reflexa (Celastraceae), Irvingia malayana (Irvingiaceae), Knema curtisii (Myristicaceae), Dysoxylum sericeum (Meliaceae), Garcinia atroviridis, Garcinia mangostana and Calophyllum inophyllum (Clusiaceae), Ervatamia hirta (Apocynaceae), Cassia alata, Entada phaseoloides and Leucaena leucocephala (Leguminosae), Oroxylum indicum (Bignoniaceae), Peronema canescens,Vitex pubescens and Premna odorata (Verbenaceae), Piper mucronatum and Piper sp. (Piperaceae), Ardisia crenata (Myrsinaceae), Lawsonia inermis (Lythraceae), Strobilanthes sp. (Acanthaceae) were able to reduce the in vitro cell viability by more than 50% when exposed to 9.6J/cm(2) of a broad spectrum light when tested at a concentration of 20 microg/mL. Six of these active extracts were further fractionated and bio-assayed to yield four photosensitisers, all of which are based on the pheophorbide-a and -b core structures. Our results suggest that the main photosensitisers from terrestrial plants are likely based on the cyclic tetrapyrrole structure and photosensitisers with other structures, if present, are present in minor amounts or are not as active as those with the cyclic tetrapyrrole structure.
    Matched MeSH terms: Photochemotherapy*
  5. In vitro and in vivo photocytotoxicity of boron dipyrromethene derivatives for photodynamic therapy
    Lim SH, Thivierge C, Nowak-Sliwinska P, Han J, van den Bergh H, Wagnières G, et al.
    J Med Chem, 2010 Apr 8;53(7):2865-74.
    PMID: 20199028 DOI: 10.1021/jm901823u
    To understand the effects of substitution patterns on photosensitizing the ability of boron dipyrromethene (BODIPY), two structural variations that either investigate the effectiveness of various iodinated derivatives to maximize the "heavy atom effect" or focus on the effect of extended conjugation at the 4-pyrrolic position to red-shift their activation wavelengths were investigated. Compounds with conjugation at the 4-pyrrolic position were less photocytotoxic than the parent unconjugated compound, while those with an iodinated BODIPY core presented better photocytotoxicity than compounds with iodoaryl groups at the meso-positions. The potency of the derivatives generally correlated well with their singlet oxygen generation level. Further studies of compound 5 on HSC-2 cells showed almost exclusive localization to mitochondria, induction of G(2)/M-phase cell cycle block, and onset of apoptosis. Compound 5 also extensively occluded the vasculature of the chick chorioallantoic membrane. Iodinated BODIPY structures such as compound 5 may have potential as new photodynamic therapy agents for cancer.
    Matched MeSH terms: Photochemotherapy*
  6. The neovessel occlusion efficacy of 15-hydroxypurpurin-7-lactone dimethyl ester induced with photodynamic therapy
    Lim SH, Nowak-Sliwinska P, Kamarulzaman FA, van den Bergh H, Wagnières G, Lee HB
    Photochem Photobiol, 2010 Mar-Apr;86(2):397-402.
    PMID: 20074086 DOI: 10.1111/j.1751-1097.2009.00684.x
    In this study, the photodynamic therapy (PDT) induced efficacy of a semi-synthesized analogue 15(1)-hydroxypurpurin-7-lactone dimethyl ester or G2, in terms of chick chorioallantoic membrane blood vessel occlusion was evaluated in reference to verteporfin. Early formulation studies showed that G2 prepared in a system of cremophor EL 2.5% and ethanol 2.5% in saline was biocompatible up to 20 microL volume of injection. Following injection, G2 accumulation peaked within the first minute and its extravasation from intra- to extra-vascular occurred somewhat slower as compared with verteporfin. In the PDT study, closure of capillaries and small neovessels was observed with 4 microg per embryo of G2 and a light dose of 20 J cm(-2) at a fluence rate of 40 mW cm(-2) filtered at 400-440 nm-a result that may be considered optimum for the treatment of age-related macular degeneration (AMD). Also, partial occlusion of the large vessels was observed using the same dose of G2 and light-an effect which is desirable for cancer treatment. From this study, we conclude that G2 has the potential to be developed as a therapeutic agent for photodynamic treatment for AMD and cancer.
    Matched MeSH terms: Photochemotherapy/methods*
  7. Combined treatment modalities for age related macular degeneration
    Das RA, Romano A, Chiosi F, Menzione M, Rinaldi M
    Curr Drug Targets, 2011 Feb;12(2):182-9.
    PMID: 20887244
    BACKGROUND: Age-related macular degeneration (AMD) is a condition that accounts for 75% of cases of legal blindness in individuals over the age of 50.

    OBJECTIVES: The objective of this review has been to evaluate the clinical effectiveness of available combined treatments modalities in the treatment of neovascular AMD.

    DATA SOURCES: Central and Medline were searched for original research studies (Phase I, II, III), abstracts, and review articles concerning combination therapies for the control of neovascular AMD. We included randomized controlled trials (RCTs).

    RESULTS: The results of therapeutic trials focused on the actual options in the management of neovascular AMD are discussed. Intravitreal treatment with substances targeting all isotypes of vascular endothelial growth factor (VEGF) results in a significant increase in visual acuity in patients with neovascular AMD. The combination with occlusive therapies like verteporfin photodynamic therapy (V-PDT) potentially offers a reduction of re-treatment frequency rate and long-term maintenance of the benefit reached. Despite the promise from combining anti-VEGF therapies with V-PDT, other combinations to improve outcomes with V-PDT deserve attention. Corticosteroids demonstrated an antiangiogenic effect and targeted the extravascular components of CNV, such as inflammatory cells and fibrocytes. Nevertheless, the study on the clinical application of corticosteroids will require a better understanding of the potential complications. Further developments interacting with various steps in the angiogenic cascade are under clinical or preclinical evaluation and may soon become available. In AMD the goal of a combination regimen is to address the therapy toward neovascular, inflammatory, and proliferative components of the disease.

    CONCLUSIONS: Combined treatments strategies are an obvious step providing disease control when it is not achieved with a single therapeutic approach. One risk of using a single therapy to control AMD is a rebound induced by compensatory stimulation of other pathogenetic pathways. Combination therapy is a logical approach to address mechanisms of disease progression that appear to be self-sustaining once initiated.

    Matched MeSH terms: Photochemotherapy*
  8. Rapid identification of cyclic tetrapyrrolic photosensitisers for photodynamic therapy using on-line hyphenated LC-PDA-MS coupled with photo-cytotoxicity assay
    Tan PJ, Appleton DR, Mustafa MR, Lee HB
    Phytochem Anal, 2012 Jan-Feb;23(1):52-9.
    PMID: 21692117 DOI: 10.1002/pca.1324
    Photodynamic therapy is a treatment modality that involves site-directed generation of cytotoxic reactive oxygen species by light-activated photosensitisers.
    Matched MeSH terms: Photochemotherapy
  9. Vitrectomy for breakthrough bleeding in age related macular degeneration and polypoidal choroidal vasculopathy in a Malaysian Hospital
    Bastion, M.L.C., Amelah, M.A.Q., Wong, H.S.
    Journal of Surgical Academia, 2012;2(2):21-26.
    MyJurnal
    This study aimed to review the risk factors and clinical outcomes of patients undergoing pars planar vitrectomy (PPV) for breakthrough bleeding (BTB) from age related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV). We performed a retrospective review of medical records of 346 patients operated by the vitreoretinal unit at Universiti Kebangsaan Malaysia Medical Centre (UKMMC), Kuala Lumpur, Malaysia from January 2008 - June 2011. We found eight eyes of 8 patients with AMD/IPCV-related BTB who underwent PPV. Mean age of patients was 64.4 years (range 41-80 years) with 5 males. Five were Chinese. Duration of symptoms ranged from days to months. Four patients were on anti-coagulants. Two had history of prior photodynamic therapy. There were five cases of PCV, of which three were macular in location. All three cases of AMD were macular. Intraoperative intravitreal ranibizumab injection was given in three cases and two had combined vitrectomy and cataract extraction. All cases reported improvement in visual acuity with four cases achieving 6/60 or better post operatively including two cases of extramacular PCV achieving 6/9 vision. Mean follow-up was 60 weeks. Postoperative complications included retinal tear and detachment in one case, reattached on reoperation. Six patients had a history of hypertension including one individual with stroke. Our small series indicates a predominance of Chinese individuals with BTB. Usage of anticoagulants and hypertension may be a predisposing factor. Better visual prognosis occurs with extramacular lesions which tend to be of PCV type.
    Matched MeSH terms: Photochemotherapy
  10. Fulltext Hypericin-photodynamic therapy leads to interleukin-6 secretion by HepG2 cells and their apoptosis via recruitment of BH3 interacting-domain death agonist and caspases
    Barathan M, Mariappan V, Shankar EM, Abdullah BJ, Goh KL, Vadivelu J
    Cell Death Dis, 2013;4:e697.
    PMID: 23807226 DOI: 10.1038/cddis.2013.219
    Photodynamic therapy (PDT) has emerged as a capable therapeutic modality for the treatment of cancer. PDT is a targeted cancer therapy that reportedly leads to tumor cell apoptosis and/or necrosis by facilitating the secretion of certain pro-inflammatory cytokines and expression of multiple apoptotic mediators in the tumor microenvironment. In addition, PDT also triggers oxidative stress that directs tumor cell killing and activation of inflammatory responses. However, the cellular and molecular mechanisms underlying the role of PDT in facilitating tumor cell apoptosis remain ambiguous. Here, we investigated the ability of PDT in association with hypericin (HY) to induce tumor cell apoptosis by facilitating the induction of reactive oxygen species (ROS) and secretion of Th1/Th2/Th17 cytokines in human hepatocellular liver carcinoma cell line (HepG2) cells. To discover if any apoptotic mediators were implicated in the enhancement of cell death of HY-PDT-treated tumor cells, selected gene profiling in response to HY-PDT treatment was implemented. Experimental results showed that interleukin (IL)-6 was significantly increased in all HY-PDT-treated cells, especially in 1 μg/ml HY-PDT, resulting in cell death. In addition, quantitative real-time PCR analysis revealed that the expression of apoptotic genes, such as BH3-interacting-domain death agonist (BID), cytochrome complex (CYT-C) and caspases (CASP3, 6, 7, 8 and 9) was remarkably higher in HY-PDT-treated HepG2 cells than the untreated HepG2 cells, entailing that tumor destruction of immune-mediated cell death occurs only in PDT-treated tumor cells. Hence, we showed that HY-PDT treatment induces apoptosis in HepG2 cells by facilitating cytotoxic ROS, and potentially recruits IL-6 and apoptosis mediators, providing additional hints for the existence of alternative mechanisms of anti-tumor immunity in hepatocellular carcinoma, which contribute to long-term suppression of tumor growth following PDT.
    Matched MeSH terms: Photochemotherapy
  11. Prioritization of natural extracts by LC-MS-PCA for the identification of new photosensitizers for photodynamic therapy
    Samat N, Tan PJ, Shaari K, Abas F, Lee HB
    Anal Chem, 2014 Feb 4;86(3):1324-31.
    PMID: 24405504 DOI: 10.1021/ac403709a
    Photodynamic therapy (PDT) is an alternative treatment for cancer that involves administration of a photosensitive drug or photosensitizer that localizes at the tumor tissue followed by in situ excitation at an appropriate wavelength of light. Tumour tissues are then killed by cytotoxic reactive oxygen species generated by the photosensitizer. Targeted excitation and photokilling of affected tissues is achieved through focal light irradiation, thereby minimizing systemic side effects to the normal healthy tissues. Currently, there are only a small number of photosensitizers that are in the clinic and many of these share the same structural core based on cyclic tetrapyrroles. This paper describes how metabolic tools are utilized to prioritize natural extracts to search for structurally new photosensitizers from Malaysian biodiversity. As proof of concept, we analyzed 278 photocytotoxic extracts using a hyphenated technique of liquid chromatography-mass spectrometry coupled with principal component analysis (LC-MS-PCA) and prioritized 27 extracts that potentially contained new photosensitizers for chemical dereplication using an in-house UPLC-PDA-MS-Photocytotoxic assay platform. This led to the identification of 2 new photosensitizers with cyclic tetrapyrrolic structures, thereby demonstrating the feasibility of the metabolic approach.
    Matched MeSH terms: Photochemotherapy*
  12. Photodynamic characterization of amino acid conjugated 15(1)-hydroxypurpurin-7-lactone for cancer treatment
    Lim SH, Yam ML, Lam ML, Kamarulzaman FA, Samat N, Kiew LV, et al.
    Mol Pharm, 2014 Sep 2;11(9):3164-73.
    PMID: 25077598 DOI: 10.1021/mp500351s
    This study aims to improve the photodynamic properties and biological effectiveness of 15(1)-hydroxypurpurin-7-lactone dimethyl ester (G2), a semisynthetic photosensitizer, for the PDT treatment of cancer. The strategy we undertook was by conjugating G2 with aspartic acid and lysine amino acid moieties. The photophysical properties, singlet oxygen generation, distribution coefficiency (Log D in octanol/PBS pH 7.4), and photostability of these analogues and their in vitro bioactivities such as cellular uptake, intracellular localization, and photoinduced cytotoxicity were evaluated. In addition, selected analogues were also investigated for their PDT-induced vasculature occlusion in the chick chorioallantoic membrane model and for their antitumor efficacies in Balb/C mice bearing 4T1 mouse mammary tumor. From the study, conjugation with aspartic acid improved the aqueous solubility of G2 without affecting its photophysical characteristics. G2-Asp showed similar in vitro and in vivo antitumor efficacies compared to the parent compound. Given the hydrophilic nature of G2-Asp, the photosensitizer is a pharmaceutically advantageous candidate as it can be formulated easily for systemic administration and has reduced risk of aggregation in vascular system.
    Matched MeSH terms: Photochemotherapy/methods
  13. In vivo studies of nanostructure-based photosensitizers for photodynamic cancer therapy
    Voon SH, Kiew LV, Lee HB, Lim SH, Noordin MI, Kamkaew A, et al.
    Small, 2014 Dec 29;10(24):4993-5013.
    PMID: 25164105 DOI: 10.1002/smll.201401416
    Animal models, particularly rodents, are major translational models for evaluating novel anticancer therapeutics. In this review, different types of nanostructure-based photosensitizers that have advanced into the in vivo evaluation stage for the photodynamic therapy (PDT) of cancer are described. This article focuses on the in vivo efficacies of the nanostructures as delivery agents and as energy transducers for photosensitizers in animal models. These materials are useful in overcoming solubility issues, lack of tumor specificity, and access to tumors deep in healthy tissue. At the end of this article, the opportunities made possible by these multiplexed nanostructure-based systems are summarized, as well as the considerable challenges associated with obtaining regulatory approval for such materials. The following questions are also addressed: (1) Is there a pressing demand for more nanoparticle materials? (2) What is the prognosis for regulatory approval of nanoparticles to be used in the clinic?
    Matched MeSH terms: Photochemotherapy*
  14. Fulltext Improved photodynamic efficacy of Zn(II) phthalocyanines via glycerol substitution
    Chin Y, Lim SH, Zorlu Y, Ahsen V, Kiew LV, Chung LY, et al.
    PLoS One, 2014;9(5):e97894.
    PMID: 24840576 DOI: 10.1371/journal.pone.0097894
    Phthalocyanines are excellent photosensitizers for photodynamic therapy as they have strong absorbance in the near infra-red region which is most relevant for in vivo activation in deeper tissular regions. However, most phthalocyanines present two major challenges, ie, a strong tendency to aggregate and low water-solubility, limiting their effective usage clinically. In the present study, we evaluated the potential enhancement capability of glycerol substitution on the photodynamic properties of zinc (II) phthalocyanines (ZnPc). Three glycerol substituted ZnPc, 1-3, (tetra peripherally, tetra non-peripherally and mono iodinated tri non-peripherally respectively) were evaluated in terms of their spectroscopic properties, rate of singlet oxygen generation, partition coefficient (log P), intracellular uptake, photo-induced cytotoxicity and vascular occlusion efficiency. Tetrasulfonated ZnPc (ZnPcS4) was included as a reference compound. Here, we showed that 1-3 exhibited 10-100 nm red-shifted absorption peaks with higher molar absorptivity, and at least two-fold greater singlet oxygen generation rates compared to ZnPcS4. Meanwhile, phthalocyanines 1 and 2 showed more hydrophilic log P values than 3 consistent with the number of glycerol attachments but 3 was most readily taken up by cells compared to the rest. Both phthalocyanines 2 and 3 exhibited potent phototoxicity against MCF-7, HCT-116 and HSC-2 cancer cell-lines with IC50 ranging 2.8-3.2 µM and 0.04-0.06 µM respectively, while 1 and ZnPcS4 (up to 100 µM) failed to yield determinable IC50 values. In terms of vascular occlusion efficiency, phthalocyanine 3 showed better effects than 2 by causing total occlusion of vessels with diameter <70 µm of the chorioallantoic membrane. Meanwhile, no detectable vascular occlusion was observed for ZnPcS4 with treatment under similar experimental conditions. These findings provide evidence that glycerol substitution, in particular in structures 2 and 3, is able to improve the photodynamic properties of ZnPc.
    Matched MeSH terms: Photochemotherapy/methods*
  15. Fulltext Targeted PDT agent eradicates TrkC expressing tumors via photodynamic therapy (PDT)
    Kue CS, Kamkaew A, Lee HB, Chung LY, Kiew LV, Burgess K
    Mol Pharm, 2015 Jan 5;12(1):212-22.
    PMID: 25487316 DOI: 10.1021/mp5005564
    This contribution features a small molecule that binds TrkC (tropomyosin receptor kinase C) receptor that tends to be overexpressed in metastatic breast cancer cells but not in other breast cancer cells. A sensitizer for (1)O2 production conjugated to this structure gives 1-PDT for photodynamic therapy. Isomeric 2-PDT does not bind TrkC and was used as a control throughout; similarly, TrkC- cancer cells were used to calibrate enhanced killing of TrkC+ cells. Ex vivo, 1- and 2-PDT where only cytotoxic when illuminated, and 1-PDT, gave higher cell death for TrkC+ breast cancer cells. A 1 h administration-to-illumination delay gave optimal TrkC+/TrkC--photocytotoxicity, and distribution studies showed the same delay was appropriate in vivo. In Balb/c mice, a maximum tolerated dose of 20 mg/kg was determined for 1-PDT. 1- and 2-PDT (single, 2 or 10 mg/kg doses and one illumination, throughout) had similar effects on implanted TrkC- tumors, and like those of 2-PDT on TrkC+ tumors. In contrast, 1-PDT caused dramatic TrkC+ tumor volume reduction (96% from initial) relative to the TrkC- tumors or 2-PDT in TrkC+ models. Moreover, 71% of the mice treated with 10 mg/kg 1-PDT (n = 7) showed full tumor remission and survived until 90 days with no metastasis to key organs.
    Matched MeSH terms: Photochemotherapy/methods*
  16. Long-term clinical effect of adjunctive antimicrobial photodynamic therapy in periodontal treatment: a randomized clinical trial
    Alwaeli HA, Al-Khateeb SN, Al-Sadi A
    Lasers Med Sci, 2015 Feb;30(2):801-7.
    PMID: 24037036 DOI: 10.1007/s10103-013-1426-y
    Mechanical removal of microbial biofilm dental plaque from tooth surfaces is important for treatment of periodontal diseases. However, the effectiveness of conventional scaling and root planing (SRP) is affected by the local conditions and residual bacteria which may affect the healing process. We performed a randomized clinical trial to test our hypothesis that adjunctive antimicrobial photodynamic therapy (aPDT) plus SRP has significant effect compared with SRP alone, which can last for 1 year. The study included 136 sites in 16 patients with previously untreated chronic periodontitis, at least one premolar and one molar in every quadrant (minimum, four teeth/quadrant) and at least one tooth with attachment loss of ≥4 mm in every quadrant. In all patients, two randomly assigned quadrants were treated with SRP and the other two were treated with SRP + aPDT. The clinical parameters of probing pocket depth (PPD), bleeding on probing (BOP), and clinical attachment level (CAL) were evaluated at baseline and after 3, 6, and 12 months. There were no significant differences between the two groups at baseline. PPD and BOP showed significant reduction, and CAL showed significant gain from baseline for all three time points in both groups. In addition, there were significantly greater reduction and gain for SRP + aPDT than for SRP at all three time points. No adverse effects of aPDT were observed. These data demonstrate significant improvement in all evaluated clinical parameters for at least 1 year and suggest that aPDT as an adjunctive therapy to SRP represents a promising therapeutic concept for persistent periodontitis.
    Matched MeSH terms: Photochemotherapy/methods*
  17. Efficacy of photodynamic therapy in the management of oral premalignant lesions. A systematic review
    Vohra F, Al-Kheraif AA, Qadri T, Hassan MI, Ahmed A, Warnakulasuriya S, et al.
    Photodiagnosis Photodyn Ther, 2015 Mar;12(1):150-9.
    PMID: 25315968 DOI: 10.1016/j.pdpdt.2014.10.001
    The aim was to systematically review the efficacy of photodynamic therapy (PDT) in the management of oral premalignant lesions.
    Matched MeSH terms: Photochemotherapy/statistics & numerical data*
  18. Photodynamic therapy mediates innate immune responses via fibroblast-macrophage interactions
    Zulaziz N, Azhim A, Himeno N, Tanaka M, Satoh Y, Kinoshita M, et al.
    Hum. Cell, 2015 Oct;28(4):159-66.
    PMID: 25997703 DOI: 10.1007/s13577-015-0118-2
    Antibacterial photodynamic therapy (PDT) has come to attract attention as an alternative therapy for drug-resistant bacteria. Recent reports revealed that antibacterial PDT induces innate immune response and stimulates abundant cytokine secretion as a part of inflammatory responses. However, the underlying mechanism how antibacterial PDT interacts with immune cells responsible for cytokine secretion has not been well outlined. In this study, we aimed to clarify the difference in gene expression and cytokine secretion between combined culture of fibroblasts and macrophages and their independent cultures. SCRC-1008, mouse fibroblast cell line and J774, mouse macrophage-like cell line were co-cultured and PDT treatments with different parameters were carried out. After various incubation periods (1-24 h), cells and culture medium were collected, and mRNA and protein levels for cytokines were measured using real-time PCR and ELISA, respectively. Our results showed that fibroblasts and macrophages interact with each other to mediate the immune response. We propose that fibroblasts initially respond to PDT by expressing Hspa1b, which regulates the NF-κB pathway via Tlr2 and Tlr4. Activation of the NF-κB pathway then results in an enhanced secretion of pro-inflammatory cytokines (TNF-α, IL-6 and IL-1β) and neutrophil chemoattractant MIP-2 and KC from macrophages.
    Matched MeSH terms: Photochemotherapy*
  19. Fulltext New Peptide-Conjugated Chlorin-Type Photosensitizer Targeting Neuropilin-1 for Anti-Vascular Targeted Photodynamic Therapy
    Kamarulzaman EE, Gazzali AM, Acherar S, Frochot C, Barberi-Heyob M, Boura C, et al.
    Int J Mol Sci, 2015 Oct 12;16(10):24059-80.
    PMID: 26473840 DOI: 10.3390/ijms161024059
    Photodynamic therapy (PDT) is a cancer treatment modality that requires three components, namely light, dioxygen and a photosensitizing agent. After light excitation, the photosensitizer (PS) in its excited state transfers its energy to oxygen, which leads to photooxidation reactions. In order to improve the selectivity of the treatment, research has focused on the design of PS covalently attached to a tumor-targeting moiety. In this paper, we describe the synthesis and the physico-chemical and photophysical properties of six new peptide-conjugated photosensitizers designed for targeting the neuropilin-1 (NRP-1) receptor. We chose a TPC (5-(4-carboxyphenyl)-10,15, 20-triphenyl chlorine as photosensitizer, coupled via three different spacers (aminohexanoic acid, 1-amino-3,6-dioxaoctanoic acid, and 1-amino-9-aza-3,6,12,15-tetraoxa-10-on-heptadecanoic acid) to two different peptides (DKPPR and TKPRR). The affinity towards the NRP-1 receptor of the conjugated chlorins was evaluated along with in vitro and in vivo stability levels. The tissue concentration of the TPC-conjugates in animal model shows good distribution, especially for the DKPPR conjugates. The novel peptide-PS conjugates proposed in this study were proven to have potential to be further developed as future NRP-1 targeting photodynamic therapy agent.
    Matched MeSH terms: Photochemotherapy/methods*
  20. Encapsulation efficacy of natural and synthetic photosensitizers by silica nanoparticles for photodynamic applications
    Makhadmeh GN, Abdul Aziz A, Abdul Razak K, Abu Noqta O
    IET Nanobiotechnol, 2015 Dec;9(6):381-5.
    PMID: 26647815 DOI: 10.1049/iet-nbt.2015.0003
    This study analysed the physical effects of Cichorium Pumilum (CP), as a natural photosensitizer (PS), and Protoporphyrin IX (PpIX), as a synthetic PS, encapsulated with silica nanoparticles (SiNPs) in photodynamic therapy. The optimum concentrations of CP and PpIX, needed to destroy Red Blood Cells (RBC), were determined and the efficacy of encapsulated CP and PpIX were compared with naked CP and PpIX was verified. The results confirmed the applicability of CP and PpIX encapsulated in SiNPs on RBCs, and established a relationship between the encapsulated CP and PpIX concentration and the time required to rupture 50% of the RBCs (t50). The CP and PpIX encapsulated in SiNPs exhibited higher efficacy compared with that of naked CP and PpIX, respectively, and CP had less efficacy compared with PpIX.
    Matched MeSH terms: Photochemotherapy/methods*
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