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1

Photodynamic therapy as adjuvant therapy in surgically treated pleural malignancies.  

PubMed Central

Five patients with a pleural malignancy (four malignant mesotheliomas and one localized low grade carcinoid) were treated with maximal surgical resection of the tumour followed by intraoperative adjuvant photodynamic therapy (PDT). The additional photodynamic treatment was performed with light of 652 nm from a high power diode laser, and meta-tetrahydroxy phenylchlorin as the photosensitizer. The light delivery to the thoracic cavity was monitored by in situ isotropic light detectors. The position of the light delivery fibre was adjusted to achieve optimal light distribution, taking account of reflected and scattered light in this hollow cavity. There was no 30-day post-operative mortality and only one patient suffered from a major complication (diaphragmatic rupture and haematopericardium). The operation time was increased by a maximum of 1 h to illuminate the total hemithoracic surface with 10 J cm(-2) (incident and scattered light). The effect of the adjuvant PDT was monitored by examination of biopsies taken 24 h after surgery under thoracoscopic guidance. Significant damage, including necrosis, was observed in the marker lesions with remaining malignancy compared with normal tissue samples, which showed only an infiltration with PMN cells and oedema of the striated muscles cells. Of the five patients treated, four are alive with no signs of recurrent tumour with a follow-up of 9-11 months. One patient was diagnosed as having a tumour dissemination in the skin around the thoracoscopy scar and died of abdominal tumour spread. Light delivery to large surfaces for adjuvant PDT is feasible in a relatively short period of time (< 1 h). In situ dosimetry ensures optimal light distribution and allows total doses (incident plus scattered light) to be monitored at different positions within the cavity. This combination of light delivery and dosimetry is well suited for adjuvant treatment with PDT in malignant pleural tumours. Images Figure 1 Figure 4

Baas, P.; Murrer, L.; Zoetmulder, F. A.; Stewart, F. A.; Ris, H. B.; van Zandwijk, N.; Peterse, J. L.; Rutgers, E. J.

1997-01-01

2

Photodynamic Therapy  

Microsoft Academic Search

Cerebral gliomas are inherently invasive tumors, and the vast majority of tumors recur locally despite optimal conventional\\u000a therapies. Photodynamic therapy has been used as an adjuvant therapy to help control the tumor locally. Photodynamic therapy\\u000a is a binary treatment involving the selective uptake of a sensitizer by the cancer cell followed by irradiation of the tumor\\u000a to activate the retained

Bhadrakant Kavar; Andrew H. Kaye

3

Adjuvant photodynamic therapy (PDT) of the superficial bladder cancer  

NASA Astrophysics Data System (ADS)

Superficial transitional cell carcinoma represents 50 to 80% of newly diagnosed bladder cancer in various countries. Transurethral resection of the urinary bladder is the standard procedure for biopsy and treatment superficial bladder cancer. However recurrence tumors after transurethral resection alone is high enough (50-90%). Intravesical chemotherapy for prophylaxis after complete transurethral resection is reducing recurrence rate about 1 5%. Adjuvant intravesical Bacillus of Calmette and Guerin (BCG) is reducing recurrence rate about 30%, but frequency side effects of this therapy is very high. Purpose of this study is appreciate efficacy adjuvant PDT with photosensitizer Photogeme (Russia) of superficial bladder cancer for prophylaxis after complete transurethral resection. The follow up was from 3 to 63 months (27 months, on average). Sixty-five patients (75.6%) showed no recurrence. For the follow up period, the recurrence was revealed in 21 (24.4%) patient, in two of them it was progressing (one case of invasive growth and one case of remote metastases). Four cases of recurrence were revealed 4 months after the surgery. In other cases, the recurrence was diagnosed from 9 to 18 months.

Sokolov, V. V.; Russakov, I. G.; Teplov, A. A.; Filonenko, E. V.; Ul'yanov, R. V.; Bystrov, A. A.

2005-08-01

4

Macrophage-directed immunotherapy as adjuvant to photodynamic therapy of cancer.  

PubMed

The effect of Photofrin-based photodynamic therapy (PDT) and adjuvant treatment with serum vitamin D3-binding protein-derived macrophage-activating factor (DBPMAF) was examined using a mouse SCCVII tumour model (squamous cell carcinoma). The results show that DBPMAF can markedly enhance the curative effect of PDT. The most effective DBPMAF therapy consisted of a combination of intraperitoneal and peritumoral injections (50 and 0.5 ng kg-1 respectively) administered on days 0, 4, 8 and 12 after PDT. Used with a PDT treatment curative to 25% of the treated tumours, this DBPMAF regimen boosted the cures to 100%. The DBPMAF therapy alone showed no notable effect on the growth of SCCVII tumour. The PDT-induced immunosuppression, assessed by the evaluation of delayed-type contact hypersensitivity response in treated mice, was greatly reduced with the combined DBPMAF treatment. These observations suggest that the activation of macrophages in PDT-treated mice by adjuvant immunotherapy has a synergistic effect on tumour cures. As PDT not only reduces tumour burden but also induces inflammation, it is proposed that recruitment of the activated macrophages to the inflamed tumour lesions is the major factor for the complete eradication of tumours. PMID:9010027

Korbelik, M; Naraparaju, V R; Yamamoto, N

1997-01-01

5

Macrophage-directed immunotherapy as adjuvant to photodynamic therapy of cancer.  

PubMed Central

The effect of Photofrin-based photodynamic therapy (PDT) and adjuvant treatment with serum vitamin D3-binding protein-derived macrophage-activating factor (DBPMAF) was examined using a mouse SCCVII tumour model (squamous cell carcinoma). The results show that DBPMAF can markedly enhance the curative effect of PDT. The most effective DBPMAF therapy consisted of a combination of intraperitoneal and peritumoral injections (50 and 0.5 ng kg-1 respectively) administered on days 0, 4, 8 and 12 after PDT. Used with a PDT treatment curative to 25% of the treated tumours, this DBPMAF regimen boosted the cures to 100%. The DBPMAF therapy alone showed no notable effect on the growth of SCCVII tumour. The PDT-induced immunosuppression, assessed by the evaluation of delayed-type contact hypersensitivity response in treated mice, was greatly reduced with the combined DBPMAF treatment. These observations suggest that the activation of macrophages in PDT-treated mice by adjuvant immunotherapy has a synergistic effect on tumour cures. As PDT not only reduces tumour burden but also induces inflammation, it is proposed that recruitment of the activated macrophages to the inflamed tumour lesions is the major factor for the complete eradication of tumours.

Korbelik, M.; Naraparaju, V. R.; Yamamoto, N.

1997-01-01

6

Cationic ceramides and analogues, LCL30 and LCL85, as adjuvants to photodynamic therapy of tumors.  

PubMed

Photodynamic therapy (PDT) is known to alter the expression of various genes in treated cells. This prompted us to examine the activity of genes encoding two important enzymes in sphingolipid (SL) metabolism, dihydroceramide desaturase (DES) and sphingosine kinase (SPHK), in mouse SCCVII tumor cells treated by PDT using either the porphyrin-based photosensitizer Photofrin or silicon phthalocyanine Pc4. The results revealed that PDT induced an upregulation in the expression of two major isoforms of both genes (DES1 and DES2 as well as SPHK1 and SPHK2). While the changes were generally moderate (2-3-fold gains), the increase in DES2 expression was more pronounced and it was much greater with Photofrin-PDT than with Pc4-PDT (over 23-fold vs. less than 5-fold). Combining either Photofrin-PDT or Pc4-PDT with the cationic C16-ceramide LCL30 (20mg/kg i.p.) for treatment of subcutaneously growing SCCVII tumors rendered important differences in the therapy outcome. Photofrin-PDT, used at a dose that attained good initial response but no tumor cures, produced 50% cures when combined with a single LCL30 treatment. In contrast, the same LCL30 treatment combined with Pc4-PDT had no significant effect on tumor response. The optimal timing of LCL30 injection was immediately after Photofrin-PDT. The therapeutic benefit was lost when LCL30 was given in two 20mg/kg injections encompassing intervals before and after PDT. LCL85, the cationic B13 ceramide analogue and SL-modulating agent, also increased cure rates of Photofrin-PDT treated tumors, but the therapeutic benefit was less pronounced than with LCL30. These results with LCL30 and LCL85, and our previous findings for LCL29 (another SL analogue), assert the potential of SLs for use as adjuvants to augment the efficacy of PDT-mediated tumor destruction. PMID:23911762

Korbelik, Mladen; Zhang, Wei; Saw, Kyi Min; Szulc, Zdzislaw M; Bielawska, Alicja; Separovic, Duska

2013-07-06

7

Evaluation of monophosphoryl lipid A as an immune adjuvant for photodynamic therapy in a rat sarcoma model: preliminary results  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is a treatment option for several forms of human cancer, and like traditional chemotherapy and ionizing radiation therapy, PDT alone is not curative for some cases. Recent efforts have aimed at developing strategies for adjuvant therapy for PDT. Given the nature of PDT-mediated cell damage, immunotherapy is a promising adjuvant for long-term control of solid tumors. A candidate immune stimulant for use with PDT is monophosphoryl lipid A (MLA), a non-toxic fraction of the endotoxin molecule. The hypothesis is that adjuvant MLA immunotherapy with PDT will improve local tumor control and prevent growth of subsequently implanted tumor cells when compared to PDT alone. To date, no significant differences in circulating leukocyte populations or tumor infiltrating lymphocyte populations have been identified in 9L tumor-bearing F344 rats after systemic administrations of MLA. Likewise, no significant difference has been identified in local tumor control following PDT of 9L tumors with or without adjuvant MLA. Further results are pending.

Lucroy, Michael D.; Edwards, Benjamin F.; Griffey, Stephen M.; Madewell, Bruce R.

1999-06-01

8

Update on photodynamic therapy.  

PubMed

To date, photodynamic therapy with verteporfin has been shown to benefit those patients with age-related molecular degeneration and choroidal neovascularization that is subfoveal and predominately classic (> 50%). As of this writing, the Food and Drug Administration is requiring additional data before verteporfin is approved for treatment of occult subfoveal choroidal neovascularization. Photodynamic therapy has also proved beneficial for subfoveal lesions secondary to high myopia. Although there is potential for patients with angioid streaks, ocular histoplasmosis syndrome, and idiopathic causes of choroidal neovascularization to benefit from photodynamic therapy, randomized clinical trials have not been performed. Photodynamic therapy has not been shown to benefit patients with minimally classic (< 50%) lesions. PMID:12777937

Landy, Jennifer; Brown, Gary C

2003-06-01

9

Photodynamic therapy: an update.  

PubMed

Photodynamic therapy (PDT) is a promising local treatment modality based on the selective accumulation of a photosensitizer in malignant tissues and the subsequent irradiation with laser light. Photodynamic therapy of malignant tumors includes biological, photochemical and photophysical processes. These processes involve: (a) absorption of photosensitizing agent; (b) selective retention of the photosensitizer in tumors and (c) irradiation of sensitized tumor by laser radiation. This report provides a review of photosensitizers, photochemistry, subcellular targets, side effects and laser involved in photodynamic therapy. In addition, gradual increase in knowledge related to in vitro and in vivo mechanisms of action of PDT, as well as some clinical applications of photodynamic therapy are presented. PMID:11845434

Dima, V F; Vasiliu, V; Dima, S V

10

[Photodynamic therapy in dermatooncology].  

PubMed

Non-melanoma skin cancers are the most common skin tumors. Because of their frequent localization on the face and hand, aesthetic aspects of the therapeutic procedures should also be considered. Surgical excision still remains the first choice, but recently several new alternative therapies have emerged, especially for the treatment of superficial skin cancer. Photodynamic therapy has become a widely accepted therapeutic method for certain non-melanoma skin tumors. Photodynamic therapy involves the use of light to activate a photosensitizer, localized in diseased tissues. Photosensitizers are tumor-selective: their accumulation in rapidly proliferating cells and newly formed blood vessels is significantly higher than in the surrounding healthy tissues. During photodynamic therapy, cytotoxic reactive oxygen species are formed from the photosensitizer, leading to changes in subcellular pathways or apoptosis of the cells. Efficacy of the photodynamic therapy has been proven in solar keratosis, superficial basal cell carcinoma and morbus Bowen, with significantly better cosmetic outcome than that of the conventional therapeutic methods. Side effects, like erythema, crusting, serous discharge, or oedema, are usually moderate, and dissolve rapidly. The present article summarizes the authors' experiences with photodynamic treatment (212 non-melanoma skin cancer patients were treated with PDT between December 2003 and January 2006), at the Department of Dermatology and Allergology, University of Szeged, Hungary, and reviews the literature of photodynamic therapy in dermatooncology. PMID:18003581

Gaál, Magdolna; Gyulai, Rolland; Baltás, Eszter; Kui, Róbert; Oláh, Judit; Kemény, Lajos

2007-11-25

11

Photodynamic Therapy in Dentistry  

Microsoft Academic Search

Photodynamic therapy (PDT), also known as photoradiation therapy, phototherapy, or photochemo-therapy, involves the use of a photoactive dye (photosensitizer) that is activated by exposure to light of a specific wavelength in the presence of oxygen. The transfer of energy from the activated photosensitizer to available oxygen results in the formation of toxic oxygen species, such as singlet oxygen and free

K. Konopka; T. Goslinski

2007-01-01

12

Photodynamic therapy for cancer  

Microsoft Academic Search

The therapeutic properties of light have been known for thousands of years, but it was only in the last century that photodynamic therapy (PDT) was developed. At present, PDT is being tested in the clinic for use in oncology — to treat cancers of the head and neck, brain, lung, pancreas, intraperitoneal cavity, breast, prostate and skin. How does PDT

Dennis E. J. G. J. Dolmans; Dai Fukumura; Rakesh K. Jain

2003-01-01

13

Verteporfin ocular photodynamic therapy.  

PubMed

This article reviews the pharmacotherapeutics of verteporfin (Visudyne), Novartis Pharma AG) used in ocular photodynamic therapy. The chemistry, pharmacokinetics and pharmacodynamics of the drug are reviewed. The article highlights and summarises the results of the multi-centre, randomised, controlled clinical trials with verteporfin to treat subfoveal choroidal neovascularisation in age-related macular degeneration, ocular histoplasmosis syndrome and pathologic myopia. In addition, the safety profile and side effects of verteporfin are discussed. PMID:14680447

Bakri, Sophie J; Kaiser, Peter K

2004-01-01

14

Cholangiocarcinoma: an emerging indication for photodynamic therapy.  

PubMed

Cholangiocarcinoma (CC) is emerging as an important treatment indication for photodynamic therapy. CCs are generally unresectable locally invasive tumors that occlude the biliary tree leading to fatal cholangitis and liver failure. Biliary decompression via stenting offers symptomatic relief but does not control tumor growth. Founded on an initial case study followed by ever more sophisticated clinical research, including randomized trials, photodynamic therapy has garnered enough momentum to be considered as part of the standard of care for these patients. Further, preliminary clinical data show the potential for benefit of the use of PDT in a neoadjuvant and adjuvant fashion to the minority of patients currently considered resectable or of border line resectability. PDT also impacts interleukin-6 levels and may form the basis for a targeted therapy approach to this disease. We review the clinical rationale, current studies and potential future directions of PDT for patients with CC. PMID:19683207

Allison, Ron R; Zervos, Emmanuel; Sibata, Claudio H

2009-06-07

15

Photodynamic Therapy (PDT): PDT Mechanisms  

PubMed Central

Photodynamic therapy (PDT) is a light based therapy used to ablate tumors. As practiced in oncology a photosensitizing agent is applied and then activated by a specific wavelength and energy of light. This light energy in the presence of oxygen will lead to the creation of the photodynamic reaction which is cyto and vasculo toxic. This paper will review the mechanisms of action of PDT and how they may be manipulated to improve clinical outcome in cancer patients.

Allison, Ron R.

2013-01-01

16

[Photodynamic therapy for actinic cheilitis].  

PubMed

Actinic cheilitis is a subtype of actinic keratosis that mainly affects the lower lip and has a higher risk of malignant transformation. Its location on the labial mucosa influences the therapeutic approach. Vermilionectomy requires local or general anesthetic and is associated with a risk of an unsightly scar, and the treatment with 5-fluorouracil or imiquimod lasts for several weeks and the inflammatory reaction can be very intense. A number of authors have used photodynamic therapy as an alternative to the usual treatments. We present 3 patients with histologically confirmed actinic cheilitis treated using photodynamic therapy with methyl aminolevulinic acid as the photosensitizer and red light at 630 nm. The clinical response was good, with no recurrences after 3 to 6 months of follow-up. Our experience supports the use of photodynamic therapy as a good alternative for the treatment of actinic cheilitis. PMID:20038368

Castaño, E; Comunión, A; Arias, D; Miñano, R; Romero, A; Borbujo, J

2009-12-01

17

Photodynamic therapy for epilepsy  

NASA Astrophysics Data System (ADS)

Epilepsy is surgically curable if the seizure focus can be localized and does not include areas of eloquent cortex. Because epileptic cells are indistinct from surrounding brain, resection typically includes normal tissue. Using the rat kindling model of epilepsy, we evaluated Photodynamic Therapy (PDT) as a super-selective lesioning technique. We present a series of pilot studies to evaluate: 1) Protoporphyrin IX (PpIX) fluorescence, 2) the efficacy of PDT to raise seizure thresholds, 3) the safety of PDT using behavioral studies, and 4) histologic results. Bipolar electrodes were chronically implanted into the cortex and animals received successive low-level stimulation generating seizures of increasing severity. Following 5-aminolevulinic acid (ALA) administration, fully kindled rats received electrical stimulation to induce a generalized seizure. Animals were irradiated with laser light focused onto a temporal craniectomy. Our results show: 1) an increase in PpIX fluorescence in the seizure group, 2) PDT treated animals failed to demonstrate seizure activity following repeat stimulation, 3) no statistically significant difference between treated and control animals were observed on behavioral tests, 4) histology showed pyknotic hippocampal pyramidal cells in the CA3 region without areas of obvious necrosis. In conclusion, this is the first report of heightened PpIX-mediated fluorescence in epileptic brain. The selective accumulation of PpIX with laser PDT may provide a less invasive and more precise technique for obliteration of epileptic foci. PDT warrants additional research to determine if this technique may augment or replace existing procedures for the surgical management of epilepsy.

Zusman, Edie; Sidhu, Manpreet; Coon, Valerie; Scott, Nicholas; Bisland, Stuart; Tsukamoto, Tara

2006-03-01

18

Photodynamic Therapy in Bone  

Microsoft Academic Search

Recent work within our group suggests that the application of photodynamic ther- apy (PDT) in bone holds considerable promise for a number of key conditions spe- cific to bone, including the treatment of primary and secondary cancers, infection, and skeletal deformity. In this chapter I will provide a synopsis of preclinical results obtained using PDT in bone that starts with

Stuart K. Bisland

19

Photodynamic therapy of nonresectable cholangiocarcinoma  

Microsoft Academic Search

Background & Aims: Successful treatment in nonresectable Bismuth type III and IV cholangiocarcinoma is seldom achieved. The aim of this study was to evaluate the effect of photodynamic therapy on cholestasis, quality of life, and survival in these patients. Methods: Nine patients with advanced nonresectable cholangiocarcinomas Bismuth type III and IV, who showed no sufficient drainage (bilirubin decrease <50%) after

Jochen Liebetruth; Stefan Schreiber; Marco Hanft; Ullrich Wruck; Virginia Fusco; Joachim M. Müller; Heide Hörtnagl; Herbert Lochs

1998-01-01

20

Adjuvant Therapy: Melanoma  

PubMed Central

With an incidence that is increasing at 2–5% per year, cutaneous melanoma is an international scourge that disproportionately targets young individuals. Despite much research, the treatment of advanced disease is still quite challenging. Immunotherapy with high-dose interferon-?2b or interleukin-2 benefits a select group of patients in the adjuvant and metastatic settings, respectively, with significant attendant toxicity. Advances in the biology of malignant melanoma and the role of immunomodulatory therapy have produced advances that have stunned the field. In this paper, we review the data for the use of interferon-?2b in various dosing ranges, vaccine therapy, and the role of radiotherapy in the adjuvant setting for malignant melanoma. Recent trials in the metastatic setting using anticytoxic T-lymphocyte antigen-4 (anti-CTLA-4) monoclonal antibody therapy and BRAF inhibitor therapy have demonstrated clear benefit with prolongation of survival. Trials investigating combinations of these novel agents with existing immunomodulators are at present underway.

Davar, Diwakar; Tarhini, Ahmad; Kirkwood, John M.

2011-01-01

21

Adjuvant Therapy for Melanoma  

PubMed Central

Estimates from the U.S. Surveillance, Epidemiology, and End Results (SEER) registry suggest that melanoma incidence will reach 70,230 in 2011, of which 8,790 will die. The rising incidence and predilection for young individuals makes this tumor a leading source of lost productive years in the society. High-dose interferon-?2b is the only agent approved for adjuvant therapy of melanoma; the improvement in relapse-free survival has been observed across nearly all published studies and meta-analyses. However toxicity affects compliance and current research is focusing upon biomarkers that may allow selection of patients with greater likelihood of response, and exploring new agents either singly or in combination that may improve upon the benefit of IFN. In this article, we review the data for the adjuvant therapy of malignant melanoma - focusing on the results obtained with various regimens testing the several formulations of interferon-?2, and the adjuvant studies of vaccines and radiotherapy. Recent advances in the treatment of metastatic disease have established a role for CTLA-4 blockade and BRAF-inhibition, and raising hopes that these agents may have a role in the adjuvant setting. At present, several trials investigating combinations of novel agents with existing immunomodulators are underway.

Davar, Diwakar; Tarhini, Ahmad A.

2012-01-01

22

Photodynamic Antifungal Therapy Against Chromoblastomycosis  

Microsoft Academic Search

Photodynamic therapy (PDT) is a minimally invasive approach, in which a photosensitizer compound is activated by exposure\\u000a to light. The activation of the sensitizer drug results in several chemical reactions, such as the production of reactive\\u000a oxygen species and other reactive molecules, which presence in the biological site leads to the damage of target cells. Although\\u000a PDT has been primarily

Juliana Pereira Lyon; Conceição de Maria Pedroso e Silva Azevedo; Leonardo Marmo Moreira; Carlos José de Lima; Maria Aparecida de Resende

23

New directions in photodynamic therapy.  

PubMed

Photodynamic therapy (PDT), a treatment approach that makes use of a photosensitizer to generate a localized toxic species in diseased tissue, has recently become an approved treatment modality. So far, however, only a handful of photosensitizers have received regulatory approval and for a small number of diseases. This chapter outlines the major limitations of PDT and speculates on the possible improvements that are required in order to advance PDT to a front line therapy. Seven areas of improvements are discussed: drug selectivity, drug delivery, light delivery, combination therapies, pigmented tumors, other potential uses, and protocol optimization. For each area, current limitations are discussed, and further required studies are recommended. PMID:12699254

Gudgin Dickson, E F; Goyan, R L; Pottier, R H

2002-12-01

24

Image-Guided Photodynamic Cancer Therapy  

Microsoft Academic Search

Photodynamic therapy is a therapeutic modality with a long history. It has been historically known in ancient India and China\\u000a for the treatment of skin disorders. In Western medicine, the first experimental evidence of photodynamic therapy was reported\\u000a by Raab et al. who observed the lethality of acridine dyes to paramecium in the presence of light [1]. The photodynamic effect

Zheng-Rong Lu; Anagha Vaidya

25

Photodynamic therapy of recurrent cerebral glioma  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) was performed on 11 cases of recurrent cerebral glioma, including 3 cases of recurrent glioblastoma, 7 of recurrent anaplastic astrocytoma, and 1 recurrent ependymoma. Hematoporphyrin derivative (HPD) was administered intravenously at a dose of 4 - 7 mg/kg 5 - 24 hours before the operation. All patients underwent a craniotomy with a nearly radical excision of the tumor following which the tumor bed was irradiated with 630 nm laser light emitting either an argon pumped dye laser or frequency double YAG pumped dye laser for 30 to 80 minutes with a total dose of 50 J/cm2 (n equals 1), 100 J/cm2 (n equals 2), 200 J/cm2 (n equals 7), and 300 J/cm2 (n equals 1). The temperature was kept below 37 degree(s)C by irrigation. Two patients underwent postoperative radiotherapy. There was no evidence of increased cerebral edema, and no other toxicity by the therapy. All patients were discharged from the hospital within 15 days after surgery. We conclude that PDT using 4 - 7 mg/kg of HPD and 630 nm light with a dose of up to 300 J/cm2 can be used as an adjuvant therapy with no additional complications. Adjuvant PDT in the treatment of recurrent glioma is better than simple surgery.

Zhu, Shu-Gan; Wu, Si-En; Chen, Zong-Qian; Sun, Wei

1993-03-01

26

Treatment of rheumatoid arthritis using photodynamic therapy  

NASA Astrophysics Data System (ADS)

The only early therapy of rheumatoid arthritis in orthopedic surgery is a synovectomy, which is restricted to more or less big joints. A laser-synovectomy of small joints is ineffective yet. An alternative method may be photodynamic therapy. In our study we describe the photodynamic effect of Photosan 3 in a cell culture study.

Hendrich, Christian; Diddens, Heyke C.; Nosir, Hany R.; Siebert, Werner E.

1994-10-01

27

Treatment of rheumatoid arthritis using photodynamic therapy  

NASA Astrophysics Data System (ADS)

The only early therapy of rheumatoid arthritis in orthopedic surgery is a synovectomy, which is restricted to more or less big joints. A laser-synovectomy of small joints is ineffective yet. An alternative method may be photodynamic therapy. In our study we describe the photodynamic effect of Photosan 3 in a cell culture study.

Hendrich, Christian; Diddens, Heyke C.; Nosir, Hany; Siebert, Werner E.

1995-03-01

28

Magnification-corrected photodynamic therapy  

Microsoft Academic Search

Background  To present a method for performing photodynamic therapy (PDT) with a constant predictable light fluence based on actual laser\\u000a spot magnification.\\u000a \\u000a \\u000a \\u000a Methods  A calibrated Gullstrand-type model eye with a scale of half circles in the centre of the artificial fundus was used for this\\u000a study. The axial length of the model eye was set to different values ranging from 20 to

Siamak Ansari-Shahrezaei; Erdem Ergun; Robert Chong; Adnan Tufail; Andreas Wedrich; Michael Stur

2007-01-01

29

[Photodynamic therapy for infectious keratitis].  

PubMed

Photodynamic therapy (PDT) has been used in ophthalmology for the last 10 years particularly for disorders of the posterior pole. In recent years PDT has been increasingly applied for corneal cross-linking in progressive keratoconus. The classical PDT is performed with porphyrins as photosensitizers and illumination with visible light of 630-635 nm wavelength and cross-linking with the photosensitizer riboflavin and ultraviolet illumination at 370 nm. Illumination of photosensitizers generates free oxygen radicals, which damage the cell membrane or nucleic acids of eukaryotic cells or even microorganisms. By cross-linking a stronger network of collagen fibers can additionally be achieved. Experimental studies have shown that PDT with higher concentrations of photosensitizers may induce necrosis and apoptosis of corneal cells and that survival of herpes simplex virus will be reduced on a LogMar scale by 4-5 lines, of Staphylococcus aureus, Pseudomonas aeruginosa or Candida albicans strains by 1-2 lines. Previous clinical studies have shown that PDT may heal bacterial or even acanthamoeba keratitis. Thus, some authors claim that photodynamic therapy may be a potential alternative in therapy resistant infectious keratitis. However, the limitations of this therapeutic option in particular need further investigation. PMID:22350551

Szentmáry, N; Goebels, S; Bischoff, M; Seitz, B

2012-02-01

30

Molecular imaging of photodynamic therapy  

NASA Astrophysics Data System (ADS)

Recent advances in light sources, detectors and other optical imaging technologies coupled with the development of novel optical contrast agents have enabled real-time, high resolution, in vivo monitoring of molecular targets. Noninvasive monitoring of molecular targets is particularly relevant to photodynamic therapy (PDT), including the delivery of photosensitizer in the treatment site and monitoring of molecular and physiological changes following treatment. Our lab has developed optical imaging technologies to investigate these various aspects of photodynamic therapy (PDT). We used a laser scanning confocal microscope to monitor the pharmacokinetics of various photosensitizers in in vitro as well as ex vivo samples, and developed an intravital fluorescence microscope to monitor photosensitizer delivery in vivo in small animals. A molecular specific contrast agent that targets the vascular endothelial growth factor (VEGF) was developed to monitor the changes in the protein expression following PDT. We were then able to study the physiological changes due to post-treatment VEGF upregulation by quantifying vascular permeability with in vivo imaging.

Chang, Sung K.; Errabelli, Divya; Rizvi, Imran; Solban, Nicolas; O'Riordan, Katherine; Hasan, Tayyaba

2006-02-01

31

Photodynamic Diagnosis and Therapy of Cancer  

SciTech Connect

This paper gives brief information about photodynamic method used in diagnosis and therapy for cancer and other human body disorders. In particular it concentrates on detection and analysis of fluorescent dye, i.e. protoporphyrin IX (PpIX) and its two-photon excitation (TPE) process, which offers photodynamic method many fascinating possibilities.

Subiel, Anna [Institute of Experimental Physics, University of Gdansk, Wita Stwosza 57, 80-952 Gdansk (Poland)

2010-01-05

32

Augmentation of tumor immunity with ENHANZYN adjuvant following verteporfin PDT: photodynamic vaccination (PDV)  

NASA Astrophysics Data System (ADS)

The immune system is implicated in the mechanism of tumor destruction following photodynamic therapy (PDT). Several investigators have shown that immune stimulation can augment PDT. In this study, a single intratumoral injection of ENHANZYNTM adjuvant was administered to tumor-bearing mice immediately following verteporfin PDT in a therapeutic modality referred to as Photodynamic Vaccination (PDV). After optimal PDT, little difference in the rate of tumor re-growth or time to tumor reappearance was seen upon addition of the adjuvant. This may be as expected as this treatment regimen results in effective long-term tumor cure in mice. The effect of adjuvant and sub-optimal PDT was less clear as both groups treated with either a high or low does of adjuvant showed tumor re-growth earlier than those animals treated with PDT alone. However, tumors of mice receiving sub-optimal PDT followed by high dose immune adjuvant did not show the rapid, uncontrolled growth seen in other groups and, in the majority of cases, tumor volume decreased steadily with time. This resulted in a superior period of survival despite the animals being tumor-bearing. Interestingly, the data obtained in this study clearly demonstrates the ability of PDT to protect against re- challenge with a second round of tumor implantation. This was seen in all groups and stresses the importance of the immune response in PDT tumor control. Addition of the high immune adjuvant does to sub-optimal PDT appeared to be the most effective treatment group in this respect, giving complete protection against tumor re-implantation.

Curry, P. M.; Stewart, A. J.; Hardwicke, L.; Smits, Claire; North, John R.

2001-07-01

33

Photodynamic Cancer Therapy - Recent Advances  

SciTech Connect

The basic principle of the photodynamic effect was discovered over a hundred years ago leading to the pioneering work on PDT in Europe. It was only during the 1980s, however, when 'photoradiation therapy' was investigated as a possible treatment modality for cancer. Photodynamic therapy (PDT) is a photochemotherapeutic process which requires the use of a photosensitizer (PS) that, upon entry into a cancer cell is targeted by laser irradiation to initiate a series of events that contribute to cell death. PSs are light-sensitive dyes activated by a light source at a specific wavelength and can be classified as first or second generation PSs based on its origin and synthetic pathway. The principle of PS activation lies in a photochemical reaction resulting from excitation of the PS producing singlet oxygen which in turn reacts and damages cell organelles and biomolecules required for cell function and ultimately leading to cell destruction. Several first and second generation PSs have been studied in several different cancer types in the quest to optimize treatment. PSs including haematoporphyrin derivative (HpD), aminolevulinic acid (ALA), chlorins, bacteriochlorins, phthalocyanines, naphthalocyanines, pheophorbiedes and purpurins all require selective uptake and retention by cancer cells prior to activation by a light source and subsequent cell death induction. Photodynamic diagnosis (PDD) is based on the fluorescence effect exhibited by PSs upon irradiation and is often used concurrently with PDT to detect and locate tumours. Both laser and light emitting diodes (LED) have been used for PDT depending on the location of the tumour. Internal cancers more often require the use of laser light delivery using fibre optics as delivery system while external PDT often make use of LEDs. Normal cells have a lower uptake of the PS in comparison to tumour cells, however the acute cytotoxic effect of the compound on the recovery rate of normal cells is not known. Subcellular localization of PS is of vital importance when cell death mechanism is identified. Programmed cell death (PCD) viz. apoptosis, necrosis and autophagy have all been identified as inducible cell death mechanisms during PDT. While apoptosis is probably the preferred cell death mechanism, understanding the molecular differences and identifying the cross-talk between these mechanisms are crucial to the development of new PSs aimed at improving the killing efficiency and overall effectiveness of PDT as a cancer treatment modality. This paper reviews the process of PDT cancer therapy, the available PSs, their effectiveness for different cancers as well as the cell death mechanisms identified during PDT of different cancers associated with specific PSs.

Abrahamse, Heidi [Laser Research Centre, Faculty of Health Sciences, University of Johannesburg, P.O. Box 17011, Doornfontein (South Africa)

2011-09-22

34

Photodynamic antifungal therapy against chromoblastomycosis.  

PubMed

Photodynamic therapy (PDT) is a minimally invasive approach, in which a photosensitizer compound is activated by exposure to light. The activation of the sensitizer drug results in several chemical reactions, such as the production of reactive oxygen species and other reactive molecules, which presence in the biological site leads to the damage of target cells. Although PDT has been primarily developed to combat cancerous lesions, this therapy can be employed for the treatment of several conditions, including infectious diseases. A wide range of microorganisms, including Gram-positive and Gram-negative bacteria, viruses, protozoa, and fungi, have demonstrated susceptibility to antimicrobial PDT. This treatment might consist in an alternative for the management of fungal infections. Antifungal photodynamic therapy has been successfully employed against Candida species, dermatophytes, and Aspergillus niger. Chromoblastomycosis is an infection that involves skin and subcutaneous tissues caused by the traumatic inoculation of dematiaceous fungi species, being that the most prevalent are Fonsecaea pedrosoi and Claphialophora carrionii. In the present work, the clinical applications of PDT for the treatment of chromoblastomycosis are evaluated. We have employed methylene blue as photosensitizer and a LED (Light Emitting Diode) device as light source. The results of this treatment are positive, denoting the efficacy of PDT against chromoblastomycosis. Considering that great part of the published works are focused on in vitro trials, these clinical tests can be considered a relevant source of information about antifungal PDT, since its results have demonstrated to be promising. The perspectives of this kind of treatment are analyzed in agreement with the recent literature involving antifungal PDT. PMID:21643843

Lyon, Juliana Pereira; Pedroso e Silva Azevedo, Conceição de Maria; Moreira, Leonardo Marmo; de Lima, Carlos José; de Resende, Maria Aparecida

2011-06-04

35

Photodynamic Therapy Treatment to Enhance Fracture Healing.  

National Technical Information Service (NTIS)

Long bone fractures resulting from high impact trauma can result in delayed healing. Photodynamic therapy (PDT) is a non-surgical, non-ionizing minimally invasive local treatment currently used to treat cancer and skin diseases. Surprisingly, recent findi...

A. J. Yee B. C. Wilson C. M. Whyne D. Nam M. K. Akens

2012-01-01

36

Appraising Adjuvant Aromatase Inhibitor Therapy  

Microsoft Academic Search

Tamoxifen, once the gold standard adjuvant endocrine therapy for early breast cancer, is being challenged by third-generation aromatase inhibitors (AIs) that have demonstrated improved disease-free survival in a vari- ety of adjuvant settings for early breast cancer. Tamoxi- fen and AIs have different safety profiles, which should allow physicians to begin to individualize treatment based on a patient's comorbidities and

Edith A. Perez

37

Photodynamic therapy of gastric cancer  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) with the use of laser endoscopic spectrum analyzer (LESA-5), the spectral-analyzing video-imaging system, Kr laser and various types of catheters for different tumor localizations, and Phthalocyanine aluminum photosensitizers in patients with gastric cancer was discussed. PDT was carried out in fifteen patients with gastric cancer. There were the following indications for PDT: early gastric cancer (3 patients), malignant stenosis of the cardia or pyloric portion of the stomach (4 patients), cancer of gastric stump with stenosis of gastrojejunal anastomosis (1 patient), preoperative treatment of patients with large but probably resectable gastric tumor size (7 patients). Usually we used 3 - 4 seances of laser treatment 10 - 30 minutes long. Concentration of photosensitizer in normal and malignant tissue was controlled by LESA-5. Treatment was monitored by spectral-analyzing video- imaging system in fluorescent light. The results show high efficiency of PDT especially in patients with early gastric cancer (necrosis of all tumor mass, i.e. complete regression of tumor). For all other patients we obtained partial regression of gastric cancer.

Kharnas, S. S.; Kuzin, N. M.; Zavodnov, V. Y.; Sclyanskaya, O. A.; Linkov, Kirill G.; Loschenov, Victor B.; Meerovich, Gennady A.; Torshina, Nadezgda L.; Stratonnikov, A. A.; Steiner, Rudolf W.

1996-01-01

38

Light distributors for photodynamic therapy  

NASA Astrophysics Data System (ADS)

A brief overview is given of light distributors developed by our group in Lausanne for photodynamic therapy (PDT) of cancer. We focus on fiberoptic devices which have to a large extent been tested over the years in the clinic for PDT of the upper aerodigestive tract, the tracheobronchial tree, the esophagus, the uterus, and the skin. Both surface and interstitial light distributors are discussed. Several different physical principles for obtaining the desired light intensity distribution in tissue are demonstrated, including the use of specially shaped reflecting surfaces, light scattering and refraction by particles, the use of flexible highly reflecting balloons, controlled fiber core surface roughening, and microlenses. PDT can be improved using 'intelligent' light distributors, which permit the measurement of the light intensity reflected from the irradiated surface, as well as the dye fluorescence signals. Both are measured in situ and in real time during the treatment. The use of such devices, which can measure photobleaching kinetics, and enable one to adjust the light dose to the observed dye fluorescence signals, thus giving better PDT control, is discussed.

van den Bergh, Hubert; Mizeret, Jerome; Theumann, Jean-Francois; Woodtli, A.; Bays, R.; Robert, D.; Thielen, P.; Philippoz, J. M.; Braichotte, Daniel; Forrer, Martin; Savary, Jean-Francois; Monnier, Philippe; Wagnieres, Georges

1995-01-01

39

Neo-adjuvant hormonal therapy.  

PubMed

Neo-adjuvant endocrine therapy has opened new alternatives for locally advanced breast cancer. Such therapy, which has permitted us to expand the treatment role of neo-adjuvant therapies, may be of great benefit to patient groups such as the elderly, those not suited for chemotherapy, and those whose response may not be optimal. This therapy also may be able to help us identify agents that could improve outcomes in the adjuvant setting as well as possible biologic predictors for outcome. The latest generation of endocrine therapy for breast cancer, aromatase inhibitors, has proved superior to tamoxifen in terms of toxicity and efficacy in the adjuvant setting and is currently being studied in other clinical trials. Current findings indicate that these agents are less toxic and better tolerated than neo-adjuvant chemotherapy and that third-generation anti-hormonal therapy offers improved tumor response compared with tamoxifen, which has resulted in increased breast conserving surgery. Biomarker findings of improved response in tumors that are both estrogen receptor positive and HER-2 positive as well as progesterone receptor positivity only will be important for planning future selective treatment and clinical trials. PMID:18373643

Valenzuela, Marcia; Julian, Thomas B

2008-03-27

40

PHOTODYNAMIC THERAPY TARGETED TO PATHOGENS  

PubMed Central

Photodynamic therapy (PDT) employs a non-toxic dye termed a photosensitizer (PS) together with low intensity visible light, which, in the presence of oxygen, produce cytotoxic species. PS can be targeted to its destination cell or tissue and, in addition, the irradiation can be spatially confined to the lesion giving PDT the advantage of dual selectivity. This promising approach can be used for various applications including microbial inactivation and the treatment of infections. Resistance to PDT has not been shown and multiantibiotic-resistant strains are as easily killed as naïve strains. It is known that Gram (+) bacteria are more sensitive to PDT as compared to Gram (?) species. However, the use of cationic PS or agents that increase the permeability of the outer membrane allows for the effective killing of Gram (?) organisms. Some PS have an innate positive charge, but our approach is to link PS to a cationic molecular vehicle such as poly-L-lysine. This modification dramatically increases PS binding to and penetrating through the negatively charged bacterial permeability barrier. Due to focused light delivery the use of PDT is possible only for localized infections. Nonetheless numerous diseases can be treated. Selectivity of the PS for microbes over host cells, accurate delivery of the PS into the infected area, and PDT dose adjustment help minimize side effects and give PDT an advantage over conventional therapy. There are only a few reports about the use of antimicrobial PDT in animal models and clinical trials. We have used genetically modified bioluminescent bacteria to follow the effect of PDT in infected wounds, burns, and soft tissue infections in mice. Not only were bacteria infecting wounds, burns, and abscesses killed, but mice were saved from death due to sepsis and wound healing was improved.

DEMIDOVA, T. N.; HAMBLIN, M. R.

2011-01-01

41

Photodynamic therapy of diseased bone  

NASA Astrophysics Data System (ADS)

Objective: Photodynamic therapy (PDT) defines the oxygen-dependent reaction that occurs upon light-mediated activation of a photosensitizing compound, culminating in the generation of cytotoxic, reactive oxygen species, predominantly, singlet oxygen. We are investigating PDT treatment of diseased bone. Methods: Using a rat model of human breast cancer (MT-1)-derived bone metastasis we confirmed the efficacy of benzoporphyrin-derivative monoacid (BPD-MA)-PDT for treating metastatic lesions within vertebrae or long bones. Results: Light administration (150 J) 15 mins after BPDMA (2.5 mg/Kg, i.v.) into the lumbar (L3) vertebra of rats resulted in complete ablation of the tumour and surrounding bone marrow 48 hrs post-PDT without paralysis. Porcine vertebrae provided a model comparable to that of human for light propagation (at 150 J/cm) and PDT response (BPD-MA; 6 mg/m2, i.v.) in non-tumour vertebrae. Precise fibre placement was afforded by 3-D cone beam computed tomography. Average penetration depth of light was 0.16 +/- 0.04 cm, however, the necrotic/non-necrotic interface extended 0.6 cm out from the treatment fiber with an average incident fluence rate of 4.3 mW/cm2. Non-necrotic tissue damage was evident 2 cm out from the treatment fiber. Current studies involving BPD-MA-PDT treatment of primary osteosarcomas in the forelimbs of dogs are very promising. Magnetic resonance imaging 24 hr post treatment reveal well circumscribed margins of treatment that encompass the entire 3-4 cm lesion. Finally, we are also interested in using 5-aminolevulinic acid (ALA) mediated PDT to treat osteomyelitis. Response to therapy was monitored as changes in bioluminescence signal of staphylococcus aureus (SA)-derived biofilms grown onto 0.5 cm lengths of wire and subjected to ALA-PDT either in vitro or in vivo upon implant into the intramedullary space of rat tibia. Transcutaneous delivery of PDT (75 J/cm2) effectively eradicated SAbiofilms within bone. Conclusions: Results support the application of PDT to the treatment of primary or metastatic lesions within bone. Secondly, that ALA-PDT may be useful as a treatment for osteomyelitis. Further studies aim to optimize the parameters of delivering PDT into bone and explore imaging technologies that can be used for clinical PDT.

Bisland, Stuart K.; Yee, Albert; Siewerdsen, Jeffery; Wilson, Brian C.; Burch, Shane

2005-08-01

42

Photodynamic therapy in neurosurgery: a review  

Microsoft Academic Search

Photodynamic therapy (PDT) has been investigated extensively, both experimentally and clinically, as an adjunctive treatment in the neuro-oncological field. It is based on the more selective accumulation of a photosensitizer in malignant than normal tissue with low systemic toxicity. Subsequent light activation induces photo-oxidation, followed by selective tumour destruction via vascular and direct cellular mechanisms. Malignant brain tumours carry a

Herwig Kostron; Alois Obwegeser; Rosanna Jakober

1996-01-01

43

Photodynamic therapy in ocular vascular disease  

Microsoft Academic Search

Photodynamic therapy (PDT) is a novel therapeutical approach which is noninvasive and potentially selective for neoplastic pathologies. Association of photosensitizers with low density lipoprotein (LDL) leads to direct targeting of the treated lesions with enhanced efficiency and selectivity. LDL-mediated PDT is particularly useful in the treatment of neo-vascular structures since LDL receptors are abundantly expressed on vascular endothelial cells. To

Ursula Schmidt-Erfurth; Reginald Birngruber; Tayyaba Hasan

1996-01-01

44

Endodontic photodynamic therapy ex vivo  

PubMed Central

Objective To evaluate the anti-microbial effects of photodynamic therapy (PDT) on infected human teeth ex vivo. Materials and Methods Fifty-two freshly extracted teeth with pulpal necrosis and associated periradicular radiolucencies were obtained from 34 subjects. Twenty-six teeth with 49 canals received chemomechanical debridement (CMD) with 6% NaOCl and twenty-six teeth with 52 canals received CMD plus PDT. For PDT, root canal systems were incubated with methylene blue (MB) at concentration of 50 µg/ml for 5 minutes followed by exposure to red light at 665 nm with an energy fluence of 30 J/cm2. The contents of root canals were sampled by flushing the canals at baseline and following CMD alone or CMD+PDT and were serially diluted and cultured on blood agar. Survival fractions were calculated by counting colony-forming units (CFU). Partial characterization of root canal species at baseline and following CMD alone or CMD+PDT was performed using DNA probes to a panel of 39 endodontic species in the checkerboard assay. Results The Mantel-Haenszel chi-square test for treatment effects demonstrated the better performance of CMD+PDT over CMD (P=0.026). CMD+PDT significantly reduced the frequency of positive canals relative to CMD alone (P=0.0003). Following CMD+PDT, 45 of 52 canals (86.5%) had no CFU as compared to 24 of 49 canals (49%) treated with CMD (canal flush samples). The CFU reductions were similar when teeth or canals were treated as independent entities. Post-treatment detection levels for all species were markedly lower for canals treated by CMD+PDT than were for those treated by CMD alone. Bacterial species within dentinal tubules were detected in 17/22 (77.3%) and 15/29 (51.7%) of canals in the CMD and CMD+PDT group, respectively (P= 0.034). Conclusion Data indicate that PDT significantly reduces residual bacteria within the root canal system, and that PDT, if further enhanced by technical improvements, holds substantial promise as an adjunct to CMD.

Ng, Raymond; Singh, Fiza; Papamanou, Despoina A.; Song, Xiaoqing; Patel, Chitrang; Holewa, Colleen; Patel, Niraj; Klepac-Ceraj, Vanja; Fontana, Carla R.; Kent, Ralph; Pagonis, Tom C.; Stashenko, Philip P.; Soukos, Nikolaos S.

2010-01-01

45

Photodynamic therapy for cancer of the pancreas  

PubMed Central

Background: Few pancreatic cancers are suitable for surgery and few respond to chemoradiation. Photodynamic therapy produces local necrosis of tissue with light after prior administration of a photosensitising agent, and in experimental studies can be tolerated by the pancreas and surrounding normal tissue. Aims: To undertake a phase I study of photodynamic therapy for cancer of the pancreas. Patients: Sixteen patients with inoperable adenocarcinomas (2.5–6 cm in diameter) localised to the region of the head of the pancreas were studied. All presented with obstructive jaundice which was relieved by biliary stenting prior to further treatment. Methods: Patients were photosensitised with 0.15 mg/kg meso-tetrahydroxyphenyl chlorin intravenously. Three days later, light was delivered to the cancer percutaneously using fibres positioned under computerised tomographic guidance. Three had subsequent chemotherapy. Results: All patients had substantial tumour necrosis on scans after treatment. Fourteen of 16 left hospital within 10 days. Eleven had a Karnofsky performance status of 100 prior to treatment. In 10 it returned to 100 at one month. Two patients with tumour involving the gastroduodenal artery had significant gastrointestinal bleeds (controlled without surgery). Three patients developed duodenal obstruction during follow up that may have been related to treatment. There was no treatment related mortality. The median survival time after photodynamic therapy was 9.5 months (range 4–30). Seven of 16 patients (44%) were alive one year after photodynamic therapy. Conclusions: Photodynamic therapy can produce necrosis in pancreatic cancers with an acceptable morbidity although care is required for tumours invading the duodenal wall or involving the gastroduodenal artery. Further studies are indicated to assess its influence on the course of the disease, alone or in combination with chemoradiation.

Bown, S G; Rogowska, A Z; Whitelaw, D E; Lees, W R; Lovat, L B; Ripley, P; Jones, L; Wyld, P; Gillams, A; Hatfield, A W R

2002-01-01

46

Heat-shock Proteins and Photodynamic Therapy  

NASA Astrophysics Data System (ADS)

Many cancer treatments, such as photodynamic therapy, generate active oxygen species, often in the mitochondria. These oxygen species adversely react with cellular processes, thereby destroying cancer cells and tissue. Heat-shock proteins are up-regulated in response to heat stress or other environmental stresses and are known to protect cells from active oxygen species. In tumor cells, heat-shock proteins accumulate in the mitochondria under non-stress conditions at higher levels than in normal cells. The objective of our work is to determine whether specific mitochondrial heat-shock proteins are responsible for the increased resistance of cancer cells to oxidative-based anti-cancer therapies. We will first determine which heat-shock proteins accumulate in the mitochondria of cancer cells (lung carcinomas). We will determine if the over-expression of specific heat-shock proteins in the mitochondria can protect cells from Photofrin®-mediated photodynamic therapy through protection of mitochondrial electron transport.

Baylis, Joanne; Downs, Craig A.; Jones, Linda R.; Heckathorn, Scott A.

1998-11-01

47

Ocular Photodynamic Therapy – Standard Applications and New Indications (Part 1)  

Microsoft Academic Search

Ocular photodynamic therapy (PDT) was introduced as a novel treatment for neovascular forms of age-related macular degeneration and choroidal neovascularization (CNV) secondary to pathologic myopia in the mid\\/end 1990s. The current treatment recommendations are based on the results of two large, prospective, multicenter, randomized clinical trials (Treatment of Age-Related Macular Degeneration with Photodynamic Therapy and Verteporfin in Photodynamic Therapy Studies)

Stefan Mennel; Irene Barbazetto; Carsten H. Meyer; Silvia Peter; Michael Stur

2007-01-01

48

Retinal pigment epithelial tear after photodynamic therapy for choroidal neovascularization  

Microsoft Academic Search

PURPOSE: To report a case of retinal pigment epithelial tear after photodynamic therapy for choroidal neovascularization.METHODS: Case report. A 74-year-old woman with exudative age-related macular degeneration and classic subfoveal choroidal neovascularization RE underwent photodynamic therapy with verteporfin.RESULTS: Ophthalmoscopy and fluorescein angiography RE disclosed a retinal pigment epithelial tear in the area of photodynamic therapy.CONCLUSION: This case presents the first report

Faik Gelisken; Werner Inhoffen; Michael Partsch; Ulrike Schneider; Ingrid Kreissig

2001-01-01

49

Photodynamic therapy and anti-tumour immunity  

Microsoft Academic Search

Photodynamic therapy (PDT) uses non-toxic photosensitizers and harmless visible light in combination with oxygen to produce cytotoxic reactive oxygen species that kill malignant cells by apoptosis and\\/or necrosis, shut down the tumour microvasculature and stimulate the host immune system. In contrast to surgery, radiotherapy and chemotherapy that are mostly immunosuppressive, PDT causes acute inflammation, expression of heat-shock proteins, invasion and

Ana P. Castano; Pawel Mroz; Michael R. Hamblin

2006-01-01

50

Antitumor immune reaction elicited by photodynamic therapy  

NASA Astrophysics Data System (ADS)

This work examines why photodynamic therapy (PDT) is capable of eliciting a strong immune reaction against treated solid tumors. It is postulated that this phenomenon originates from the basic charter of the insult inflicted by the photodynamic treatment, which is dominated by singlet oxygen-mediated oxidative stress. The early event associated with this initial impact, which is of major relevance for the development of immune response, is the generation of photo-oxidative lesions responsible for the activation of cellular signal transduction pathways and consequent induction of stress proteins. Importantly, these lesions, as well as other types of PDT mediated oxidative injury, have a strong pro-inflammatory character. It is suggested that the antitumor immune response is primed and propagated by the PDT-induced inflammatory process. Of critical importance for the immune recognition of treated tumor is the generation of large amounts of cancer cell debris that occurs rapidly following PDT treatment.

Korbelik, Mladen

1999-06-01

51

Exploiting apoptosis in photodynamic therapy: is it possible?  

NASA Astrophysics Data System (ADS)

Glioblastoma Multiforme is the most common form of malignant brain tumors and accounts for approximately 25% of all primary brain tumors. Only 5% of these patients survive longer than 2 years. The standard form of treatment is radiation therapy and surgery if the site is accessible. Different forms of adjuvant chemotherapy have been largely proven unsuccessful. Another form of adjuvant therapy, Photodynamic Therapy (PDT), has undergone preliminary trials showing some promising results but at the cost of increased side effects like rise in intracranial blood pressure and neurological deficiency. Apoptotic cell kill used as a biological treatment endpoint can possibly ameliorate these side effects. This study evaluates the significance of apoptotic cell death in the 9L rat gliosarcoma using the aminolevulinic acid (ALA) induced endogenous photosensitizer Protophorphyrin IX (PpIX). A strong influence of drug incubation time with cell kill was observed. The percentage of apoptotic cell death was less than 10% for 2 and 4 hours incubation times and irradiation times ensuring up to 70 and 80% cell kill respectively. Accumulation of PpIX in the mitochondria and cytoplasm was quantified by confocal fluorescence microscopy showing a linear relationship of PpIX fluorescence with concentration. The possibility of an in vitro threshold in the PDT dose is discussed, above which cell repair mechanisms may become exhausted. In conclusion for the range of parameters investigated, apoptotic cell kill may be hard to exploit therapeutically in this tumor model.

Rendon, Cesar A.; Lilge, Lothar D.

2003-06-01

52

Clinical improvement in Darier's disease with photodynamic therapy.  

PubMed

We report a patient with Darier's disease successfully treated with photodynamic therapy. She had previously been recalcitrant to treatment with emollients, topical corticosteroids and retinoids. Photodynamic therapy was trialled with significant clinical improvement in her cutaneous symptoms and signs that was maintained for over 27 months. PMID:20148839

Avery, Helen L; Hughes, Bronwyn R; Coley, Carol; Cooper, Hywel L

2010-02-01

53

Photoangioplasty: new applications of photodynamic therapy in atherosclerosis  

NASA Astrophysics Data System (ADS)

Atherosclerosis has traditionally held appeal as a pathologic entity in which photodynamic therapy might arrest or reverse the manifestations of disease. Earlier attempts to bring photodynamic therapy to the human clinical arena were hampered by the limitations of the photosensitizers under investigation, including the propensity to phototoxic manifestations and light-induced trauma to surrounding, normal vascular tissues. Many of these inherent limitations may be circumvented by newer photosensitizers that are activated at longer, more optimal wavelengths of light energy. Advances in fiberoptic catheter design for the endovascular delivery of light have also contributed to the greater applicability of photodynamic therapy to human atherosclerosis. Initial experiences with one family of photosensitizers, the texaphyrins, indicate that photodynamic therapy of human peripheral arterial atherosclerosis is feasible, safe, and well-tolerated. Photodynamic therapy of atherosclerosis holds promise for the treatment of de novo atherosclerosis and may have future applicability in the treatment, and perhaps prevention, of restenosis.

Rockson, Stanley G.

2000-05-01

54

Key Role of Human ABC Transporter ABCG2 in Photodynamic Therapy and Photodynamic Diagnosis  

PubMed Central

Accumulating evidence indicates that ATP-binding cassette (ABC) transporter ABCG2 plays a key role in regulating the cellular accumulation of porphyrin derivatives in cancer cells and thereby affects the efficacy of photodynamic therapy and photodynamic diagnosis. The activity of porphyrin efflux can be affected by genetic polymorphisms in the ABCG2 gene. On the other hand, Nrf2, an NF-E2-related transcription factor, has been shown to be involved in oxidative stress-mediated induction of the ABCG2 gene. Since patients have demonstrated individual differences in their response to photodynamic therapy, transcriptional activation and/or genetic polymorphisms of the ABCG2 gene in cancer cells may affect patients' responses to photodynamic therapy. Protein kinase inhibitors, including imatinib mesylate and gefitinib, are suggested to potentially enhance the efficacy of photodynamic therapy by blocking ABCG2-mediated porphyrin efflux from cancer cells. This review article provides an overview on the role of human ABC transporter ABCG2 in photodynamic therapy and photodynamic diagnosis.

Ishikawa, Toshihisa; Nakagawa, Hiroshi; Hagiya, Yuichiro; Nonoguchi, Naosuke; Miyatake, Shin-ichi; Kuroiwa, Toshihiko

2010-01-01

55

Photodynamic therapy for treatment subretinal neovascularization  

NASA Astrophysics Data System (ADS)

This work are devoted our experience with photodynamic therapy (PDT) with <> for patients with choroidal neovascularization (CNV). 18 patients with subfoveal CNV in age-related macular degeneration (AMD), 24 patients with subfoveal CNV in pathological myopia (PM) and 4 patients with subfoveal CNV associated with toxoplasmic retinochoroiditis were observed. CNV was 100% classic in all study patients. Standardized protocol refraction, visual acuity testing, ophthalmologic examinations, biomicroscopy, fluorescein angiography, and ultrasonography were performed before treatment and 1 month, 3 months, 6 months, and 1 year after treatment; were used to evaluate the results of photodynamic therapy with <> (0.02% solution of mixture sulfonated aluminium phtalocyanine 0.05 mg/kg, intravenously). A diode laser (<>, Inc, Moscow) was used operating in the range of 675 nm. Need for retreatment was based on fluorescein angiographic evidence of leakage at 3-month follow-up intervals. At 3, 6, 9 month 26 (56.5%) patients had significant improvement in the mean visual acuity. At the end of the 12-month minimal fluorescein leakage from choroidal neovascularization was seen in 12 (26.1%) patients and the mean visual acuity was slightly worse than 0.2 which was not statistically significant as compared with the baseline visual acuity. Patients with fluorescein leakage from CNV underwent repeated PDT with <>. 3D-mode ultrasound shown the decreasing thickness of chorioretinal complex in CNV area. Photodynamic therapy with <> can safely reduce the risk of severe vision loss in patients with predominantly classic subfoveal choroidal neovascularization secondary to AMD, PM and toxoplasmic retinochoroiditis.

Avetisov, Sergey E.; Budzinskaja, Maria V.; Kiseleva, Tatyana N.; Balatskaya, Natalia V.; Gurova, Irina V.; Loschenov, Viktor B.; Shevchik, Sergey A.; Kuzmin, Sergey G.; Vorozhtsov, Georgy N.

2007-06-01

56

Adjuvant radiation therapy for stage II thymoma  

Microsoft Academic Search

Background. Thymoma is difficult to study because of its indolent natural history. The criteria for administration of adjuvant radiation therapy remain controversial, and it is unclear whether patients with Masaoka stage II thymoma benefit from adjuvant radiation. The goal of this report was to determine whether or not this group benefits from radiation therapy in terms of disease-specific survival and

Abeel A Mangi; Cameron D Wright; James S Allan; John C Wain; Dean M Donahue; Hermes C Grillo; Douglas J Mathisen

2002-01-01

57

Role of multidrug resistance in photodynamic therapy  

NASA Astrophysics Data System (ADS)

Multidrug resistance in cancer chemotherapy is a well established phenomenon. One of the most common phenotypical changes in acquired or intrinsic multidrug resistance in human tumor cells is the overexpression of the mdrl gene product P-glycoprotein, which acts as an active efflux pump. Increased levels of P-glycoprotein are associated with resistance to a variety of anticancer drugs commonly used in tumor chemotherapy like anthracyclins, vinca- alcaloids, epipodophyllotoxins or actinomycin D. We investigated the efficacy or photodynamic therapy in the treatment of tumor cells expressing the multidrug resistance phenotype. Our data show that multidrug resistant cells are highly cross resistant to the phototoxic stain rhodamine 123 but exhibit only low degrees of cross resistance (2 - 3 -folds) to the photosensitizers Photosan-3, Clorin-2, methylene blue and meso-tetra (4- sulfonatophenyl) porphine (TPPS4). Resistance is associated with a decrease in intracellular accumulation of the photosensitizer. Verapamil, a membrane active compound known to enhance drug sensitivity in multidrug resistant cells by inhibition of P-glycoprotein, also increases phototoxicity in multidrug resistant cells. Our results imply that tumors expressing the multidrug resistance phenotype might fail to respond to photochemotherapy with rhodamine 123. On the other hand, multidrug resistance may not play an important role in photodynamic therapy with Photosan-3, Chlorin-2, methylene blue or TPPS4.

Diddens, Heyke C.

1992-06-01

58

Photosensitizer and light diffusion through dentin in photodynamic therapy.  

PubMed

Photodynamic therapy has been considered a potential antimicrobial modality against oral infections, including dental caries. A model to estimate the penetration of both photosensitizers and light through human dentin, a factor of interest in photodynamic therapy, is proposed. The photoacoustic spectroscopy technique was used to evaluate in vitro dentin permeability of three different photosensitizers. Using the dentin optical absorption and scattering coefficients, it was possible to propose a semi-quantitative model predicting both photosensitizer and light doses within dentin. The graphic illustrations obtained provided guidelines that may be useful in photodynamic therapy protocols used as antimicrobial tools in caries lesions. PMID:23703574

Nogueira, Ana C; Graciano, Ariane X; Nagata, Juliana Y; Fujimaki, Mitsue; Terada, Raquel S S; Bento, Antonio C; Astrath, Nelson G C; Baesso, Mauro L

2013-05-01

59

Combination of photodynamic therapy with anti-cancer agents.  

PubMed

Degenerative diseases such as cancer usually involve more than one pathological process. Therefore, attempts to combat such diseases with monotherapeutic approaches may not always do so efficiently. For this reason, the use of combination therapy with modalities that target different disease pathways represents an alternative strategy. Photodynamic therapy (PDT) has already been established as an alternative therapy for the treatment of various types of malignant disorders, including oesophageal, lung and bladder cancer as well as other degenerative diseases. This technique involves the administration of a tumor localizing photosensitizer followed by its activation with light of a specific wavelength. In the presence of tissue oxygen, the photoactive sensitizer triggers a series of photochemical and photobiological processes that may lead to direct cancer cell damage, tumor microvascular occlusion and host immune response. Due to these multiple actions, PDT has increasingly gained recognition as a potential adjuvant for conventional cancer treatments. Several preclinical studies and some clinical trials suggest that the use of PDT in combination with established treatments or with newly-developed modalities may be of benefit as compared to the individual modalities. In this review, we briefly introduce the reader to the main photobiological aspects of PDT, and then discuss the use of PDT in combination with other pharmacological approaches for the treatment of cancer. PMID:18673216

Zuluaga, M-F; Lange, N

2008-01-01

60

Photodynamic Cancer Therapy--Recent Advances  

NASA Astrophysics Data System (ADS)

The basic principle of the photodynamic effect was discovered over a hundred years ago leading to the pioneering work on PDT in Europe. It was only during the 1980s, however, when ``photoradiation therapy'' was investigated as a possible treatment modality for cancer. Photodynamic therapy (PDT) is a photochemotherapeutic process which requires the use of a photosensitizer (PS) that, upon entry into a cancer cell is targeted by laser irradiation to initiate a series of events that contribute to cell death. PSs are light-sensitive dyes activated by a light source at a specific wavelength and can be classified as first or second generation PSs based on its origin and synthetic pathway. The principle of PS activation lies in a photochemical reaction resulting from excitation of the PS producing singlet oxygen which in turn reacts and damages cell organelles and biomolecules required for cell function and ultimately leading to cell destruction. Several first and second generation PSs have been studied in several different cancer types in the quest to optimize treatment. PSs including haematoporphyrin derivative (HpD), aminolevulinic acid (ALA), chlorins, bacteriochlorins, phthalocyanines, naphthalocyanines, pheophorbiedes and purpurins all require selective uptake and retention by cancer cells prior to activation by a light source and subsequent cell death induction. Photodynamic diagnosis (PDD) is based on the fluorescence effect exhibited by PSs upon irradiation and is often used concurrently with PDT to detect and locate tumours. Both laser and light emitting diodes (LED) have been used for PDT depending on the location of the tumour. Internal cancers more often require the use of laser light delivery using fibre optics as delivery system while external PDT often make use of LEDs. Normal cells have a lower uptake of the PS in comparison to tumour cells, however the acute cytotoxic effect of the compound on the recovery rate of normal cells is not known. Subcellular localization of PS is of vital importance when cell death mechanism is identified. Programmed cell death (PCD) viz. apoptosis, necrosis and autophagy have all been identified as inducible cell death mechanisms during PDT. While apoptosis is probably the preferred cell death mechanism, understanding the molecular differences and identifying the cross-talk between these mechanisms are crucial to the development of new PSs aimed at improving the killing efficiency and overall effectiveness of PDT as a cancer treatment modality. This paper reviews the process of PDT cancer therapy, the available PSs, their effectiveness for different cancers as well as the cell death mechanisms identified during PDT of different cancers associated with specific PSs.

Abrahamse, Heidi

2011-09-01

61

Responses of tumor tissues to photodynamic therapy  

NASA Astrophysics Data System (ADS)

The mechanisms of photosensitized tumor destruction during photodynamic therapy (PDT) appear to be a complex interplay of processes involving several tissular components, such as malignant cells, microvasculature, specific blood constituents and non-vascular stroma. While vascular aberrations are of major importance when PDT is performed with Photofrin II, which is the photosensitizer most frequently used in clinical PDT, the initial pattern of tumor damage can be substantially modified by factors that alter the distribution of the photosensitizer in the neoplastic tissue. Such factors include the chemical structure of the photosensitizer, its physico-chemical properties (especially, the degree of hydrophobicity), the modality of its transport in the bloodstream, and the use of delivery systems.

Jori, Giulio

1994-03-01

62

Death pathways associated with photodynamic therapy  

PubMed Central

When the mitochondria and/or the endoplasmic reticulum were targeted by photodynamic therapy, photodamage to the anti-apoptotic protein Bcl-2 was observed. This led to an apoptotic outcome if that death pathway was available. Lysosomal photodamage ultimately resulted in activation of the pro-apoptotic protein Bid, also leading to apoptosis. Photodamage to the plasma membrane was associated with migration of sensitizers to the cytosol and procaspase photodamage, with apoptosis impaired. Where apoptosis was unavailable because of lack of necessary components of the program, an autophagic outcome has been observed. It is also clear that autophagy can occur along with apoptosis as a PDT response, and may play a role in immunologic responses to photodamaged tumor cells.

Kessel, David

2009-01-01

63

Initiation of Autophagy by Photodynamic Therapy  

PubMed Central

Photodynamic therapy (PDT) involves the irradiation of photosensitized cells with light. Depending on localization of the photosensitizing agent, the process can induce photodamage to the endoplasmic reticulum (ER), mitochondria, plasma membrane, and/or lysosomes. When ER or mitochondria are targeted, antiapoptotic proteins of the Bcl-2 family are especially sensitive to photodamage. Both apoptosis and autophagy can occur after PDT, autophagy being associated with enhanced survival at low levels of photodamage to some cells. Autophagy can become a cell-death pathway if apoptosis is inhibited or when cells attempt to recycle damaged constituents beyond their capacity for recovery. While techniques associated with characterization of autophagy are generally applicable, PDT introduces additional factors related to unknown sites of photodamage that may alter autophagic pathways. This chapter discusses issues that may arise in assessing autophagy after cellular photodamage.

Kessel, David; Oleinick, Nancy L.

2010-01-01

64

Photodynamic therapy: superficial and interstitial illumination  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is reviewed using the treatment of skin tumors as an example of superficial lesions and prostate cancer as an example of deep-lying lesions requiring interstitial intervention. These two applications are among the most commonly studied in oncological PDT, and illustrate well the different challenges facing the two modalities of PDT-superficial and interstitial. They thus serve as good examples to illustrate the entire field of PDT in oncology. PDT is discussed based on the Lund University group's over 20 yr of experience in the field. In particular, the interplay between optical diagnostics and dosimetry and the delivery of the therapeutic light dose are highlighted. An interactive multiple-fiber interstitial procedure to deliver the required therapeutic dose based on the assessment of light fluence rate and sensitizer concentration and oxygen level throughout the tumor is presented.

Svanberg, Katarina; Bendsoe, Niels; Axelsson, Johan; Andersson-Engels, Stefan; Svanberg, Sune

2010-07-01

65

[The place of photodynamic therapy in gynecology].  

PubMed

Photodynamic therapy (PDT) is a specific anticancer treatment that received significant interest in several medical and surgical disciplines. The technique is based on (i) the application of the photosensitizer that accumulates in a variable time in the neoplasic lesions and on (ii) excitation (by light whose wavelength coincides with the absorption peak of the photosensitizer) that (iii) finally causes the destruction of the lesion. This technique allows a minimally-invasive, effective and targeted treatment of some gynecological diseases. Experimental and/or clinical studies have been conducted on vulvar intraepithelial neoplasia, cervical intraepithelial neoplasia, ovarian cancer, breast cancer, dysfunctional uterine bleeding, endometriosis and vulvar lichen sclerosus. We aim to present the principles of PDT and to expose the main indications and ways of research of this technique in gynecology today. PMID:17951090

Ascencio, M; Collinet, P; Cosson, M; Vinatier, D; Mordon, S

2007-10-22

66

New strategies in colon cancer adjuvant therapy.  

PubMed

Adjuvant therapy in colorectal cancer has always been a controversy during years. Despite the fact that benefit of adjuvant therapy in stage III is clear, a more controversial question concerns efficacy in stage II. The introduction of new drugs in addition to standard regimens has some benefit, but also adds toxicity. Ongoing studies with novel targeted therapies will show their results in the next years. Other open questions include duration of therapy and whether there is a real possibility of selecting patients for treatment on the basis of prognostic factors. PMID:16760294

Labianca, R; Mosconi, S; Garassino, M C

2006-06-01

67

Mitochondria-targeting for improved photodynamic therapy  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is an emerging cancer therapeutic modality, with great potential to selectively treat surface cancers, thus minimizing systemic side effects. In this dissertation, two approaches to deliver photosensitizers to mitochondria were investigated: 1) Reducing photosensitizer sizes to improve endocytosis and lysosomal localization. Upon irradiation the photosensitizers would then produce singlet oxygen which could rupture the lysosomal membrane releasing the lysosomally trapped photosensitizers to the cytosol, from where they could relocalize to mitochondria by passive diffusion (photochemical internalization). 2) Using delocalized lipophilic cationic dyes (DLCs) to exploit membrane potential differences between the cytoplasm and mitochondria in delivering photosensitizers to mitochondria. To investigate the effects of steric hindrance on mitochondrial localization and photodynamic response, a series of eight thiaporphyrins were studied. Two new thiaporphyrin analogues 6 and 8 with reduced steric hindrance at the 10- and 15- meso positions were studied in comparison to 5,20-diphenyl-10,15-bis[4 (carboxymethyleneoxy)-phenyl]-21,23-dithiaporphyrin 1, previously validated as a potential second generation photosensitizer. Although 6 showed an extraordinarily high uptake (7.6 times higher than 1), it was less potent than 1 (IC 50 = 0.18 muM versus 0.13 muM) even though they both showed similar sub-cellular localization patterns. This low potency was attributed to its high aggregation tendency in aqueous media (4 times higher than 1), which might have affected its ability to generate singlet oxygen in vitro . 8 on the other hand showed an even lower potency than 6 (2.28 vs 0.18 muM). However this was attributed to its low cellular uptake (20 times less than 6) and inefficient generation of singlet oxygen. Overall, although the structural modifications did improve the cellular uptake of 6, 6 was still less potent than the lead photosensitizers 1. Thus, other strategies to target mitochondria for improved photodynamic activity were investigated. In a continuing project, we evaluated the ability of delocalized lipophilic cationic dyes to deliver photosensitizers to mitochondria by exploiting the membrane potential difference between the cytoplasm and mitochondria. Two conjugates: a porphyrin--rhodamine B conjugate (TPP--Rh) and a porphyrin-acridine orange conjugate (TPP--AO), each possessing a single delocalized lipophilic cation, were designed and synthesized. The conjugates were synthesized by conjugating a monohydroxy porphyrin (TPP-OH) to rhodamine B (Rh B) and acridine orange base (AO), respectively, via saturated hydrocarbon linkers. To evaluate the efficiency of the conjugates as photosensitizers, their photophysical properties and in vitro photodynamic activities were studied in comparison to those of TPP-OH, the parent porphyrin photosensitizer. Although fluorescence energy transfer (FRET) was observed in the conjugates, they were capable of generating singlet oxygen at rates comparable to TPP-OH. In a final project, we evaluated the photophysical potential of TPP-Rh to act as a two-photon photosensitizer for PDT. Two-photon PDT is a rational approach used to improve light penetration through the skin. Rhodamine B is an effective two-photon chromophore and could significantly improve the two-photon absorption of the porphyrin photosensitizer in the TPP-Rh dyad system following energy transfer. Thus the porphyrin--rhodamine B dyad (TPP--Rh), previously demonstrated to preferentially accumulate in the mitochondria, was photophysically evaluated as a potential two-photon photosensitizer. To evaluate the efficiency of TPP-Rh as a two-photon photosensitizer, its two-photon photophysical properties were compared with those of its individual components (Rh B and TPP-OH). This included: the two-photon cross sections (sigma 2), RET kinetics and dynamics and rates of singlet oxygen generation. A FRET efficiency of ~99 % was observed from the Rh moiety (donor) to the TPP moiety (acceptor) of the system. This sig

Ngen, Ethel J.

68

Photodynamic Therapy for Infections: Clinical Applications  

PubMed Central

Background and Objective Photodynamic therapy (PDT) was discovered over 100 years ago by its ability to kill various microorganisms when the appropriate dye and light were combined in the presence of oxygen. However it is only in relatively recent times that PDT has been studied as a treatment for various types of localized infections. This resurgence of interest has been partly motivated by the alarming increase in drug resistance amongst bacteria and other pathogens. This review will focus on the clinical applications of antimicrobial PDT. Study Design/Materials and Methods The published peer-reviewed literature was reviewed between 1960 and 2011. Results The basics of antimicrobial PDT are discussed. Clinical applications of antimicrobial PDT to localized viral infections caused by herpes and papilloma viruses, and nonviral dermatological infections such as acne and other yeast, fungal and bacterial skin infections are covered. PDT has been used to treat bacterial infections in brain abscesses and non-healing ulcers. PDT for dental infections including periodontitis and endodontics has been well studied. PDT has also been used for cutaneous Leishmaniasis. Clinical trials of PDT and blue light alone therapy for gastric Helicobacter pylori infection are also covered. Conclusion As yet clinical PDT for infections has been mainly in the field of dermatology using 5-aminolevulanic acid and in dentistry using phenothiazinium dyes. We expect more to see applications of PDT to more challenging infections using advanced antimicrobial photosensitizers targeted to microbial cells in the years to come.

Kharkwal, Gitika B.; Sharma, Sulbha K.; Huang, Ying-Ying; Dai, Tianhong; Hamblin, Michael R.

2012-01-01

69

Photodynamic therapy: a promising alternative in oncology  

NASA Astrophysics Data System (ADS)

Photodynamic Therapy (PDT) is a treatment modality that is based on the administration of a photosensitizer and the following application of light in a wavelength range matching the absorption spectrum of the photosensitizer. Ideally the photosensitizer retains in the tumor tissue more than in normal tissue and thus allows targeted destruction of cancerous tissue. The use of PDT is slowly being accepted as a standard treatment for certain types of cancer. This includes mainly treatment strategies with only palliative intentions (obstructive esophageal cancer and advanced lung cancer) while for certain malignant conditions new applications exists that are already intended for cure (e.g. early stage of lung cancer). The main advantage of PDT is that the treatment can be repeated multiple times safely without major side effects. PDT can be safely combined with already established treatment options like surgery, chemotherapy or radiotherapy. A disadvantage of PDT is the only localized effect of the therapy, which usually cannot significantly alter the outcome of a systemic disease. In this paper we review the history of PDT as well as current clinical applications in oncology and future directions.

Nelius, Thomas; de Riese, Werner T. W.; Filleur, Stephanie

2004-07-01

70

Regulatory pathways in photodynamic therapy induced apoptosis.  

PubMed

Photodynamic therapy is an approved treatment for several types of tumors and certain benign diseases, based on the use of a light-absorbing compound (photosensitizer) and light irradiation. In the presence of molecular oxygen, light-activation of the photosensitizer, which accumulates in cancer tissues, leads to the local production of reactive oxygen species that kill the tumor cells. Mitochondria are central coordinators of the mechanisms by which PDT induces apoptosis in the target cells. Recent studies indicate that concomitant to the permeabilization of the outer mitochondrial membrane (which leads to the release of several apoptogenic factors in the cytosol and to the activation of effector caspases), regulatory signaling pathways are activated in a photosensitizer, PDT dose and cell-dependent fashion. Signaling pathways regulated by members of mitogen activated protein kinases and their downstream targets, such as cyclooxygenase-2, appear to critically modulate cancer cell sensitivity to PDT. Understanding the molecular events that contribute to PDT-induced apoptosis, and how cancer cells can evade apoptotic death, should enable a more rationale approach to drug design and therapy. PMID:15295626

Agostinis, Patrizia; Buytaert, Esther; Breyssens, Hilde; Hendrickx, Nico

2004-03-08

71

Combination immunotherapy and photodynamic therapy for cancer  

NASA Astrophysics Data System (ADS)

Cancer is a leading cause of death among modern people largely due to metastatic disease. The ideal cancer treatment should target both the primary tumor and the metastases with minimal toxicity towards normal tissue. This is best accomplished by priming the body's immune system to recognize the tumor antigens so that after the primary tumor is destroyed, distant metastases will also be eradicated. Photodynamic therapy (PDT) involves the IV administration of photosensitizers followed by illumination of the tumor with red light producing reactive oxygen species leading to vascular shutdown and tumor cell death. Anti-tumor immunity is stimulated after PDT due to the acute inflammatory response, generation of tumor-specific antigens, and induction of heat-shock proteins. Combination regimens using PDT and immunostimulating treatments are likely to even further enhance post-PDT immunity. These immunostimulants are likely to include products derived from pathogenic microorganisms that are effectively recognized by Toll-like receptors and lead to upregulation of transcription factors for cytokines and inflammatory mediators. The following cascade of events causes activation of macrophages, dendritic and natural killer cells. Exogenous cytokine administration can be another way to increase PDT-induced immunity as well as treatment with a low dose of cyclophosphamide that selectively reduces T-regulatory cells. Although so far these combination therapies have only been used in animal models, their use in clinical trials should receive careful consideration.

Hamblin, Michael R.; Castano, Ana P.; Mroz, Pawel

2006-03-01

72

A Review of Progress in Clinical Photodynamic Therapy  

PubMed Central

Photodynamic therapy (PDT) has received increased attention since the regulatory approvals have been granted to several photosensitizing drugs and light applicators world-wide. Much progress has been seen in basic sciences and clinical photodynamics in recent years. This review will focus on new developments of clinical investigation and discuss the usefulness of various forms of PDT techniques for curative or palliative treatment of malignant and non-malignant diseases.

Huang, Zheng

2005-01-01

73

Photodynamic therapy of advanced malignant tumors  

NASA Astrophysics Data System (ADS)

Forty patients with advanced tumors were treated by photodynamic therapy (PDT) from May 1991 to August 1991 in our hospital with age ranges from 30 to 81 years old. The pathological diagnosis shows that 13 had tumors in the colon, 3 in the stomach, 2 in the oesophageal, 2 in the palatum, 1 in the cervix, and 19 others with malignant cancers of the skin. The histology was as follows: squamous cell in 20, adenocarcinoma in 19, melanocarcinoma in 1. By TNM classification there were no cases of T1, 5 cases of T2, and 35 cases of T2 - T3. All patients were stage IV. The overall effective rate was 85%, our experience is that the PDT is suitable for the patients with advanced tumor, especially those whose tumor recurrences are hard to treat after conventional treatment (surgery, radiotherapy, chemotherapy). The PDT appears to be a new and promising possibility to treat advanced tumors and to improve the patients' survival rates.

Wang, Lian-Xing; Dai, Lu-Pin; Lu, Wen-Qin

1993-03-01

74

Light delivery schemes for uterine photodynamic therapy  

NASA Astrophysics Data System (ADS)

The use of photodynamic therapy in the removal of the endometrial layer of the uterus provides the possibility of a rapid and effective treatment of menorrhagia avoiding the difficulties and complications of conventional methods. A treatment is proposed in which topical application of 5-aminolaevulinic acid to the inner surface of the uterus is followed by illumination at 630 nm. The surface layer would in this way be rendered necrotic to slough off over subsequent days. The removal of the entire endometrium must be achieved in order to prevent the return of the original condition, which demands that a therapeutic dose of both light and photosensitizer must be achieved throughout the depth of the tissue. This work presents a method of light delivery suitable for intra-uterine PDT along with in vitro optical phantom and ex vivo tissue measurements that aid in the characterization of the light field prior to treatment. These measurements allow the prediction of a treatment time suitable for the delivery of an effective light dose.

Stringer, Mark R.; Hudson, Emma J.; Dunkley, Colin P.; Boyce, Jeanetta C.; Gannon, Michael J.; Smith, Michael A.

1994-03-01

75

Photodynamic therapy using a protoporphyrinogen oxidase inhibitor.  

PubMed

The use of endogenously created porphyrins as an alternative to photosensitizer injection for photodynamic therapy is a rapidly evolving area of study. One common method to induce porphyrin synthesis and accumulation in cells is the topical, oral, or parenteral administration of 5-aminolevulinic acid, a precursor for heme biosynthesis. Porphyrin accumulation may also be elicited by the use of enzyme inhibitors of the heme biosynthetic pathway. Groups of DBA/2 mice bearing SMT-F mammary tumors were placed on a diet containing 0-4000 ppm of a protoporphyrinogen oxidase inhibitor, FP-846. This agent blocks a critical step in porphyrin metabolism and results in elevated intracellular levels of protoporphyrin IX. Light treatment of tumors produced both initial and long-term regression that was dependent on the amount of inhibitor, the duration of inhibitor exposure to animals, and the amount of light used in PDT. Tumor regression occurred without significant destruction of normal tissues in the treatment field and without initial vascular constriction or blood flow stasis. Tumor cure in animals given 4000 ppm FP-846 in feed for 3 days and 300 J/cm2 602-670 nm light (23% cure) was similar to the response in animals given 10 mg/kg Photofrin and the same light dose (20%). PMID:9377568

Fingar, V H; Wieman, T J; McMahon, K S; Haydon, P S; Halling, B P; Yuhas, D A; Winkelman, J W

1997-10-15

76

Photodynamic Therapy of Symptomatic Choroidal Nevi  

PubMed Central

Purpose: To evaluate the role of photodynamic therapy (PDT) for patients with symptomatic choroidal nevi involving the fovea or located near the fovea with subretinal fluid extending to the fovea. Materials and Methods: Retrospective review of five patients who underwent PDT for choroidal nevi at two separate centers in Ankara and Barcelona. Results: The mean initial logMAR visual acuity was 0.5 (range: 0 to 1.5). The mean largest tumor base diameter was 3.2 mm (range: 2.1–4.5 mm) and the mean tumor thickness was 1.1 mm (range: 0.7–1.6 mm). The mean number of PDT sessions was 1.6 (range:1–3). The mean final tumor thickness was 1.0 mm (range: 0–1.6 mm) at a mean follow-up of 19 months (range: 12–32 months). The mean final logMAR visual acuity was 0.4 (range: 0–1.5). Subfoveal fluid disappeared or decreased significantly in 4 of 5 eyes (80%) after PDT. Conclusions: PDT led to resolution of subretinal fluid with preservation of visual acuity in many symptomatic choroidal nevi in this study. Careful case selection is important as PDT of indeterminate pigmented tumors may delay the diagnosis and treatment of an early choroidal melanoma and thereby increase the risk for metastasis.

Amselem, Luis; Gunduz, Kaan; Adan, Alfredo; Karsl?oglu, Melisa Zisan; Rey, Amanda; Sabater, Noelia; Valldeperas, Xavier

2011-01-01

77

Is photodynamic therapy a solution for keloid?  

PubMed

Keloid is a common skin condition, especially in people of Asian and African decent. The treatment of keloid is still unsatisfactory. Photodynamic therapy (PDT) is a novel treatment for this condition, but is widely used in treating certain skin pre-malignant and malignant lesions due to its high efficiency and safety. Another aspect of PDT is its scarless (or minimal scarring) wound healing after treatment despite the fact that it causes skin inflammation. There are a few independent reports that indicate 5-aminolevulinic acid (ALA) or methylaminolevulinate (MAL)-PDT may be effective in keloid and hypertrophic scars. The mechanism is largely unknown. PDT may exert these effects by acting on keratinocytes and fibroblasts or directly on collagen/extracellular matrix (ECM) in keloid tissues, by inducing keloid fibroblast apoptosis/necrosis, modulating growth factor and cytokine expression, reducing collagen/ECM synthesis and causing degeneration of formed collagen/ECM. These potential mechanisms and the scope for topical PDT of keloids are considered in this article. PMID:22095178

Nie, Z

2011-12-01

78

[Photodynamic therapy in choroidal new vessels].  

PubMed

Photodynamic therapy (PDT) is a new approach for subfoveal choroidal new vessels (CNV) in age-related macular degeneration (ARM) and myopia, currently being evaluated in clinical trials. PDT is a two-step procedure: the intravenous perfusion of a photosensitizer is followed by light irradiation at the adapted wavelength. Verteporfin, the photosensitizer under investigation, has a maximum absorption at 692nm. Phase I and II studies determined the settings necessary to obtain optimal effects in humans with Verteporfin in the phase III study. It has been shown that this treatment is efficient and preserves initial visual acuity in 67% of Verteporfin-treated ARM eyes vs 39% of placebo-treated ARM eyes at 1 year. Fluorescein angiographic follow-up found a photo-occlusion of the CNV 14 days after treatment application followed by a partial reperfusion or reproliferation of the CNV at 3 months, resulting in the need for repeated treatments. Two-year results of the Phase III randomized clinical trial are awaited. PMID:11351216

Soubrane, G

2001-04-01

79

Photodynamic therapy (PDT) as a biological modifier  

NASA Astrophysics Data System (ADS)

The capacity of photosensitizers and light to ablate cancerous tissues and unwanted neovasculature constitutes the classical application of photodynamic therapy (PDT). Cell death results from either necrotic or apoptotic processes. The use of photosensitizers and light at doses which do not cause death has been found to affect changes in certain cell populations which profoundly effect their expression of cell surface molecules and secretion of cytokines, thereby altering the functional attributes of the treated cells. Cells of the immune system and the skin may be sensitive to modulation by 'sub-lethal PDT.' Ongoing studies have been conducted to assess, at the molecular level, changes in both lymphocytes and epidermal cells (EC) caused by treatment with low levels of benzoporphyrin derivative monoacid ring A (BPD) (a photosensitizer currently in clinical trials for cancer, psoriasis, endometriosis and age-related macular degeneration) and light. Treatment of skin with BPD and light, at levels which significantly enhanced the length of murine skin allograft acceptance, have been found to down-regulate the expression of Langerhans cell (LC) surface antigen molecules [major histocompatibility complex (MHC) class II and intracellular adhesion molecule (ICAM)-1] and the formation of some cytokines (tumor necrosis factor-alpha (TNF- (alpha) ).

Obochi, Modestus; Tao, Jing-Song; Hunt, David W.; Levy, Julia G.

1996-04-01

80

Multifocal photodynamic therapy for diffuse choroidal hemangioma  

PubMed Central

Background A choroidal hemangioma is an uncommon benign vascular tumor of the choroid that can be either circumscribed or diffuse. In our experience, diffuse choroidal hemangiomas in Asian patients often require multiple photodynamic therapy (PDT) treatment sessions. Methods We here provide a case report of a 7-year-old boy with Sturge–Weber syndrome who presented with diffuse choroidal hemangioma in the left eye. Five sessions of PDT treatment were required over a period of 1 year and a final optical coherence tomogram 3 months later revealed resolution of subretinal fluid and the choroidal hemangioma. Results Final visual acuity was 20/100 in the left eye with resolution of subretinal fluid. This case report illustrates that a single application of PDT using standard published parameters was insufficient to achieve the destruction of the enlarged vessels. This experience is similar to previous Chinese reports on circumscribed choroidal hemangiomas. The decision for repeat treatment was based on subretinal fluid recurrence, rather than complete tumor regression. Conclusion Our case report supports previous suggestions that larger dilated vessels in the vascular network of a choroidal hemangioma might affect the efficacy and selectivity of PDT in treating the eyes of Asian patients – which may explain the need for multiple treatments.

Ang, Marcus; Lee, Shu-Yen

2012-01-01

81

Tissue temperature monitoring during interstitial photodynamic therapy  

NASA Astrophysics Data System (ADS)

During ?-aminolevulinic acid (ALA) based Interstitial Photodynamic Therapy (IPDT) a high light fluence rate is present close to the source fibers. This might induce an unintentional tissue temperature increase of importance for the treatment outcome. In a previous study, we have observed, that the absorption in the tissue increases during the treatment. A system to measure the local tissue temperature at the source fibers during IPDT on tissue phantoms is presented. The temperature was measured by acquiring the fluorescence from small Cr3+-doped crystals attached to the tip of the illumination fiber used in an IPDT-system. The fluorescence of the Alexandrite crystal used is temperature dependent. A ratio of the intensity of the fluorescence was formed between two different wavelength bands in the red region. The system was calibrated by immersing the fibers in an Intralipid solution placed in a temperature controlled oven. Measurements were then performed by placing the fibers interstitially in a pork chop as a tissue phantom. Measurements were also performed superficially on skin on a volunteer. A treatment was conducted for 10 minutes, and the fluorescence was measured each minute during the illumination. The fluorescence yielded the temperature at the fiber tip through the calibration curve. The measurements indicate a temperature increase of a few degrees during the simulated treatment.

Svensson, Jenny; Johansson, Ann; Svanberg, Katarina; Andersson-Engels, Stefan

2005-04-01

82

Photodynamic therapy (PDT) for lung cancer  

NASA Astrophysics Data System (ADS)

The Yorkshire Laser Centre has been engaged in Photodynamic Therapy (PDT) since 1990. In this article we present our experience highlighting the lesson learnt. 280 bronchoscopic PDT treatments have been carried out in 160 patients divided in 2 groups. Group A: (Nr 144) with advanced inoperable disease and Group E (Nr 16) with early stage cancer. PDT method was intravenous administration of 2mg/kg bw of Photofrin followed by bronchoscopic illumination of 630nm laser light. There was no procedure-related mortality. A total of 9 cases of photosensitivity (skin burn) occurred in the series (5.6% of patients). Every patient in both groups expressed their total satisfaction to treatment. Group A: Symptom relief was achieved in all. This was matched by improvement in significant bronchial opening (58.1%). Survival was 9.6 months (mean).This was greater in patients with better performance status and lower stage of disease. Group E: Every patient had a complete response to treatment. Survival in this group was 75.4 months (mean). We conclude that bronchoscopic PDT is indicated in both advanced and early stage lung cancer. In the former it provides symptomatic relief in all and survival benefit in some; in the latter it achieves long survival and potential cure.

Moghissi, K.; Dixon, Kate

2005-11-01

83

Photodynamic therapy of cervical intraepithelial neoplasia using hexaminolevulinate and methylaminolevulinate  

NASA Astrophysics Data System (ADS)

Cervical intraepithelial neoplasia (CIN) is the precursor of invasive cervical cancer. Previous studies indicated that photodynamic therapy (PDT) represents an effective treatment modality in CIN. In 28 patients with CIN 1 - 3, 1 - 2 cycles of PDT were conducted using hexaminolevulinate (HAL) or methylaminolevulinate (MAL) and a special light delivery system. After 6 months, biopsies were obtained to assess response. The overall response rate for complete or partial response was 65%. Photodynamic therapy using new ALA esters is effective and may offer unique advantages in the therapy of CIN.

Soergel, Philipp; Staboulidou, Ismini; Hertel, Herrmann; Schippert, Cordula; Hillemanns, Peter

2009-06-01

84

Photodynamic therapy: Biophysical mechanisms and molecular responses  

NASA Astrophysics Data System (ADS)

In photodynamic therapy (PDT), photochemical reactions induced by optical activation of sensitizer molecules cause destruction of the target tissue. In this thesis we present results of several related studies, which investigated the influence of photophysical properties and photobleaching mechanisms of sensitizers and oxygen-dependent tissue optical properties on PDT treatment efficacy. The bleaching mechanism of the sensitizer meso-tetra hydroxyphenyl chlorin (mTHPC) is examined indirectly using measurements of photochemical oxygen consumption during PDT irradiation of multicell tumor spheroids. Analysis of the results with a theoretical model of oxygen diffusion that incorporates the effects of sensitizer photobleaching shows that mTHPC is degraded via a singlet-oxygen (1O2)-mediated bleaching process. The analysis allows us to extract photophysical parameters of mTHPC which are used to account for its enhanced clinical photodynamic potency in comparison to that of Photofrin. Evaluation of the spatially-resolved fluorescence in confocal optical sections of intact spheroids during PDT irradiation allows for the direct experimental verification of mTHPC's 1O2-mediated bleaching mechanism. The technique is also used to investigate the complex bleaching kinetics of Photofrin. The results allow us to successfully reconcile apparently contradictory experimental observations and to confirm the predictions of a new theoretical model in which both 1O2 and excited triplet sensitizer molecules are allowed to contribute to photobleaching. Based on studies performed in tissue-simulating erythrocyte phantoms and in a murine tumor model in vivo, we present clinically relevant results which indicate that a shift toward increased hemoglobin-oxygen saturation due to improved tissue oxygenation reduces PDT treatment beam attenuation and may allow for more effective treatment of deeper lesions. Finally, we investigate the induction of the stress protein, heat shock protein 70 (HSP70), in response to mTHPC-PDT. The studies are performed using a murine tumor cell line transfected with a plasmid containing the gene for Green Fluorescent Protein (GFP) under the control of an hsp70 promoter. We obtain increased levels of GFP fluorescence at a cellular level and in vivo in response to sub-lethal doses of mTHPC-PDT. These results demonstrate the potential of using fluorescent reporter proteins as biomarkers of PDT-induced oxidative stress.

Mitra, Soumya

85

Laser effect in photodynamic therapy of tumors  

NASA Astrophysics Data System (ADS)

Photodynamic therapy is a method that provides a reasonable alternative to other treatment modalities for patients with certain cancers, and in some cases may be the preferred treatment. The therapy implies the intravenous administration of a light-sensitive substance, the photosensitizer. The used sensitizer must absorb at long wavelength. For these purposes, the carbon dioxide laser, He-Ne and the argon laser are particularly suitable. In this study we evaluate in vitro the cytotoxic activity of three synthesized metallo-phthalocyanines with absorption bands in the red part of the spectrum: zinc-di-sulphonated phthalocyanine (ZnS2Pc), zinc-tri-sulphonated phthalocyanine (ZnS3Pc) and zinc-tetrasulphonated phthalocyanine (ZnS4Pc). Some cellular models have been used in this paper, in order to optimize the conditions of this method, as we are presenting in this paper (LSR-SF(SR) - transplantable sarcoma in rat induced by Rous sarcoma virus strain Schmidt-Ruppin; LSCC-SF(Mc29) - transplantable chicken hepatoma induced by the myelocytomatosis virus Mc29, MCF-7 cell line (human breast adenocarcinoma) derived from a patient with metastatic breast cancer, 8-MG-BA - glioblastoma multiforme 8-MG-BA, K562 - lymphoblastic human cell line, LLC-WRC 256 - Walker epithelial carcinoma. Activation of these photosensitizers retained in the cancerous cells, by red light emitted from a He-Ne laser at ?= 632.8 nm laser system, or by a diode laser emitting at 672 nm, produces a photochemical reaction that results in the selective destruction of tumor cells.

Ion, Rodica-Mariana; Brezoi, Dragos-Viorel; Neagu, Monica; Manda, Gina; Constantin, Carolina

2007-04-01

86

Role of Photodynamic Therapy in the Management of Gastrointestinal Cancer  

Microsoft Academic Search

Background: Surgery for cancer of the gastrointestinal tract is associated with high morbidity and mortality, especially in older patients. A significant proportion of patients cannot be cured and would be referred for palliative therapy. Others may have early cancer but are deemed unfit for surgery. Chemotherapy and external radiotherapy are suitable for only a proportion of patients. Therefore, photodynamic therapy

A. K. Kubba

1999-01-01

87

Photodiagnosis and photodynamic therapy of peritoneal metastasis of ovarian cancer.  

PubMed

Ovarian cancer is among the deadliest in women. Current treatment strategies fail to cure many patients owing to the difficulties of eradicating peritoneal implants frequently associated with this pathology. Photodynamic therapy represents a promising treatment as it offers many advantages over alternative strategies: diagnostic properties, specific targeting of abnormal cells, possibility to be combined with other therapies. PMID:22369725

Guyon, Laurie; Ascencio, Manuel; Collinet, Pierre; Mordon, Serge

2011-10-01

88

Versatile Photosensitizers for Photodynamic Therapy at Infrared Excitation  

PubMed Central

A new type of photosensitizers used in photodynamic therapy, which is based on photon upconverting nanoparticles, is reported. These photosensitizers are excitable with infrared irradiation, which has several times larger tissue penetration depth than the currently available ones. They are brought close to the target cancer cells through antigen-antibody interaction with good specificity and versatility. The design is also flexible in that various photosensitive molecules can be potentially adopted into the design. Results from in vitro experiments demonstrate their promise of becoming the next generation photodynamic therapy drugs.

Zhang, Peng; Steelant, Wim; Kumar, Manoj; Scholfield, Matthew

2008-01-01

89

Nonthermal cardiac catheter ablation using photodynamic therapy.  

PubMed

Background- Radiofrequency ablation has limitations, largely related to creation of lesions by heating. Here, we report the first nonthermal ablation by applying photodynamic therapy (PDT) to cardiac tissues using a custom-made deflectable laser catheter. The present study investigated the feasibility of PDT for cavotricuspid isthmus ablation in a canine model. Methods and Results- We evaluated the pharmacokinetic profiles of 17 canines after administration of a photosensitizer (talaporfin sodium) by various protocols. We succeeded in maintaining the photosensitizer concentration at a level in excess of the clinically effective dose for humans. Using a 4-polar 7-French deflectable laser catheter, we performed PDT-mediated cavotricuspid isthmus ablation in 8 canines. PDT caused oxidative injury only to the irradiated area and successfully produced a persistent electric conduction block. No acute, gross changes such as edematous degeneration, thrombus formation, steam pops, or traumatic injury were observed after irradiation. Hematoxylin and eosin staining of tissues samples also showed well-preserved endothelial layers. Testing of the blood samples taken before and after the procedure revealed no remarkable changes. Lesion size at 2 weeks after the procedure and the temperature data collected during irradiation were compared between the PDT and irrigated radiofrequency ablation procedures. A ventricular cross-section revealed a solid PDT lesion, which was as deep as a radiofrequency lesion. In addition, endocardial, surficial, and intramural temperature monitoring during the PDT irradiation clearly demonstrated the nonthermal nature of the ablation technique. Conclusions- Nonthermal PDT-mediated catheter ablation is a potentially novel treatment for cardiac arrhythmias. PMID:23995252

Kimura, Takehiro; Takatsuki, Seiji; Miyoshi, Shunichiro; Fukumoto, Kotaro; Takahashi, Mei; Ogawa, Emiyu; Ito, Arisa; Arai, Tsunenori; Ogawa, Satoshi; Fukuda, Keiichi

2013-08-31

90

Mechanisms of Resistance to Photodynamic Therapy  

PubMed Central

Photodynamic therapy (PDT) involves the administration of a photosensitizer (PS) followed by illumination with visible light, leading to generation of reactive oxygen species. The mechanisms of resistance to PDT ascribed to the PS may be shared with the general mechanisms of drug resistance, and are related to altered drug uptake and efflux rates or altered intracellular trafficking. As a second step, an increased inactivation of oxygen reactive species is also associated to PDT resistance via antioxidant detoxifying enzymes and activation of heat shock proteins. Induction of stress response genes also occurs after PDT, resulting in modulation of proliferation, cell detachment and inducing survival pathways among other multiple extracellular signalling events. In addition, an increased repair of induced damage to proteins, membranes and occasionally to DNA may happen. PDT-induced tissue hypoxia as a result of vascular damage and photochemical oxygen consumption may also contribute to the appearance of resistant cells. The structure of the PS is believed to be a key point in the development of resistance, being probably related to its particular subcellular localization. Although most of the features have already been described for chemoresistance, in many cases, no cross-resistance between PDT and chemotherapy has been reported. These findings are in line with the enhancement of PDT efficacy by combination with chemotherapy. The study of cross resistance in cells with developed resistance against a particular PS challenged against other PS is also highly complex and comprises different mechanisms. In this review we will classify the different features observed in PDT resistance, leading to a comparison with the mechanisms most commonly found in chemo resistant cells.

Casas, Adriana; Di Venosa, Gabriela; Hasan, Tayyaba; Batlle, Alcira

2013-01-01

91

Adjuvant therapy for pancreatic cancer: current status.  

PubMed

Only 5% to 15% of patients with pancreatic adenocarcinoma are candidates for a potentially curative resection. Evidence that postoperative adjuvant therapy improves outcome has been limited to a single randomized trial of a well tolerated split-course, 5-Fluorouracil (5-FU) based, chemoradiation regimen. More aggressive regimens have since been developed and are associated with, at best, a modest improvement in patient outcome. The potentially significant morbidity associated with pancreaticoduodenectomy, which can compromise the delivery of postoperative adjuvant chemoradiation, has led to the development of preoperative (adjuvant/neoadjuvant chemoradiation) regimens in these patients. Although experience suggests that such an approach is feasible, the ultimate impact warrants further evaluation. In addition, despite evolving experiences towards more dose intensive pre or postoperative adjuvant chemoradiation regimens, the problem of distant metastases remains significant. New chemotherapeutic agents, such as gemcitabine, appear to have the potential to produce better results than those achieved over the last quarter century with 5-FU. A cooperative group study has recently been activated and is evaluating its impact in an adjuvant setting when given in addition to 5-FU based chemoradiation. In the meantime, ongoing investigations into optimal integration of different therapeutic modalities, along with advances in surgery, radiation, and systemic therapy, should lead us towards further improvements in outcomes for these patients. PMID:9820740

Regine, W F; John, W J; Mohiuddin, M

1998-11-15

92

Pattern electroretinographic results after photodynamic therapy alone and photodynamic therapy in combination with intravitreal bevacizumab for choroidal neovascularization in age-related macular degeneration  

Microsoft Academic Search

Purpose To evaluate the changes in pattern electroretinography (PERG) 1 month after photodynamic therapy alone and photodynamic therapy\\u000a in combination with intravitreal bevacizumab for choroidal neovascularization (CNV) secondary to age-related macular degeneration\\u000a (AMD). Methods This is a prospective series of 45 eyes with subfoveal CNV secondary to AMD. Twenty eyes were treated with photodynamic therapy\\u000a (PDT) with verteporfin and 1.25 mg

Ayse Oner; Koray Gumus; Hatice Arda; Yudum Yuce; Sarper Karakucuk; Ertugrul Mirza

2009-01-01

93

Optical delivery and monitoring of photodynamic therapy of prostate cancer  

NASA Astrophysics Data System (ADS)

Photodynamic therapy of recurrent prostate cancer is currently undergoing Phase II clinical trials with the vascular targeting drug TOOKAD. Proper PDT dosage requires sound estimates of the light fluence and drug concentration throughout the organ. The treatment requires multiple diffusing light delivery fibers placed in position according to a light dose treatment plan under ultrasound guidance. Fluence rate is monitored by multiple sensor fibers placed throughout the organ and in sensitive organs near the prostate. The combination of multiple light delivery and fluence sensor fibers is used to estimate the optical properties of the tissue and to provide a general fluence map throughout the organ. This fluence map is then used to estimate extent of photodynamic dose. Optical spectroscopy is used to monitor drug pharmacokinetics in the organ and blood hemodynamics within the organ. Further development of these delivery and monitoring techniques will permit full online monitoring of the treatment that will enable real-time patient-specific delivery of photodynamic therapy.

Weersink, Robert A.; Bogaards, Arjun; Gertner, Mark; Davidson, Sean; Zhang, Kai; Netchev, George; Giewercer, David J.; Trachtenberg, John; Wilson, Brian C.

2004-10-01

94

Targeted photodynamic therapy with multiply-loaded recombinant antibody fragments  

Microsoft Academic Search

Current photodynamic therapy (PDT) of cancer is limited by ineffi- ciencies involved in specifically targeting photosensitizers to tumors. Although antibodies are being explored as targeting vehicles, they present significant challenges, particularly in terms of pharmacokinetics and drug-coupling. We describe here a novel and effective system to covalently attach multiple photosensitizer molecules (both preclinical, pyropheophorbide-a and clinically approved, verteporfin photosensitizers) to

Manpreet Bhatti; Gokhan Yahioglu; Lionel R. Milgrom; Mitla Garcia-Maya; Kerry A. Chester; Mahendra P. Deonarain

2008-01-01

95

Dynamics of phthalocyanine Al accumulation in stomach cancer photodynamic therapy  

NASA Astrophysics Data System (ADS)

Methods of stomach cancer photodynamic therapy with the use of Kr laser and photosensitizer-phthalocyanine (Al-Pc) are discussed. The level of preparation accumulation in the tumor and surrounding tissues has been investigated with the use of laser spectroanalyzer LESA-4 (`Biospec'). Dynamics of (Al-Pc) accumulation investigated depend on different types of tumors and different parameters of laser irradiation.

Kharnas, S. S.; Loschenov, Victor B.; Stratonnikov, A. A.; Kramarenko, T. A.; Artemjeva, O. V.; Bakonin, V. P.; Kuzin, M. I.; Zavodnov, V. Y.; Steiner, Rudolf W.

1995-01-01

96

Light delivery and light dosimetry for photodynamic therapy  

Microsoft Academic Search

Photodynamic therapy (PDT) has attracted attention because it was considered to be a selective form of cancer treatment causing minimal damage to normal tissues. This is not exactly true, because the ratio between the photosensitizer concentrations in tumour and surrounding normal tissues is not always much more than one. Nevertheless, tumour destruction by PDT with relatively little damage to normal

Willem M. Star

1990-01-01

97

Multifunctional gold nanoparticles for photodynamic therapy of cancer  

Microsoft Academic Search

As an important and growing branch of photomedicine, photodynamic therapy (PDT) is being increasingly employed in clinical applications particularly for the treatment of skin cancer. This dissertation focuses on the synthesis, characterization and deployment of gold nanoparticles for enhanced PDT of fibrosarcoma cancer cells. We have developed robust strategies and methods in fabrication of gold nanoparticles with positively- and negatively-tethered

Maung Kyaw Khaing Oo

2010-01-01

98

Long-term survival after photodynamic therapy for esophageal cancer  

Microsoft Academic Search

Background\\/Aims: Photodynamic therapy (PDT) has been adapted to the endoscopic treatment of digestive cancer, but its indications and efficacy remain uncertain. The aim of this study was to assess its feasibility in the curative treatment of small esophageal tumors. Methods: From 1983 to 1991, PDT was used to treat 123 patients with esophageal cancer who were recommended for nonsurgical treatment

Alain Sibille; René Lambert; Jean-Christophe Souquet; Ghislaine Sabben; Françoise Descos

1995-01-01

99

Pretreatment to Enhance Protoporphyrin IX Accumulation in Photodynamic Therapy  

Microsoft Academic Search

The response rates of photodynamic therapy (PDT) vary widely. Limited uptake of topically applied 5-aminolaevulinic acid (ALA), or its methyl ester (MAL), and suboptimal production of protoporphyrin IX (PpIX) may account for these differences. Recently, we demonstrated that hyperkeratosis is an important negative factor in ALA uptake. This review has its focus on pretreatment of the skin in order to

M. J. P. Gerritsen; T. Smits; M. M. Kleinpenning; P. E. J. van Erp

2009-01-01

100

Hypoxia-inducible factor-1? (HIF-1?) and photodynamic therapy  

Microsoft Academic Search

Summary form only given. Photodynamic therapy (PDT) is a promising treatment modality that is being tested in the clinic for use in oncology. PDT requires three elements: light, a photosensitizer and oxygen. PDT-mediated oxidative stress elicits direct tumor cell damage and microvascular injury within exposed tumor. Microvasculature damage following PDT leads to a significant decrease in blood flow as well

Lin-Hung Wei; Chia-Hung Chou; Jen-Liang Su

2004-01-01

101

Photodynamic therapy: discriminating between healthy and cancerous tissue  

Microsoft Academic Search

New two-photon-activated porphyrin designs allow specific, noninva- sive targeting of subcutaneous tumors several centimeters below the skin surface. Photodynamic therapy (PDT) is a noninvasive technique in which specific compounds, termed photosensitizers, are intro- duced into the bloodstream and subsequently incorporated into tissues throughout the body. Application of a specific wave- length of light can discreetly activate these compounds, leading to

Charles Spangler; Mikhail Drobizhev; Jean Starkey

2008-01-01

102

Photodynamic Therapy for Barrett's Esophagus and Esophageal Carcinoma  

PubMed Central

This paper reviews the use of photodynamic therapy (PDT) in patients with Barrett's esophagus and esophageal carcinoma. We describe the history of PDT, mechanics, photosensitizers for PDT in patients with esophageal disease. Finally, we discuss its utility and limitations in this setting.

Qumseya, Bashar J.; David, Waseem

2013-01-01

103

Successful photodynamic therapy for nonresectable cholangiocarcinoma: a randomized prospective study  

Microsoft Academic Search

Background & Aims:In nonrandomized trials, photodynamic therapy (PDT) had a promising effect on nonresectable cholangiocarcinoma (NCC). This prospective, open-label, randomized, multicenter study with a group sequential design compared PDT in addition to stenting (group A) with stenting alone (group B) in patients with NCC.

Marianne E. J Ortner; Karel Caca; Frieder Berr; Jochen Liebetruth; Ulrich Mansmann; Dominik Huster; Winfried Voderholzer; Guido Schachschal; Joachim Mössner; Herbert Lochs

2003-01-01

104

Neurotrophic Factors Minimize the Retinal Toxicity of Verteporfin Photodynamic Therapy  

Microsoft Academic Search

PURPOSE. A prior study showed that brain-derived neurotrophic factor (BDNF) rescues photoreceptors from collateral retinal damage caused by photodynamic therapy (PDT). This study was conducted to determine whether ciliary neurotrophic fac- tor (CNTF), a combination of BDNF and CNTF, or pigment epithelial cell-derived growth factor (PEDF) might protect pho- toreceptors and retinal function more effectively than BDNF. Also investigated was

Daniel M. Paskowitz; Kate M. Donohue-Rolfe; Haidong Yang; Douglas Yasumura; Michael T. Matthes; Kamran Hosseini; Carolyn M. Graybeal; George Nune; Marco A. Zarbin; Matthew M. LaVail; Jacque L. Duncan

2007-01-01

105

BDNF Reduces the Retinal Toxicity of Verteporfin Photodynamic Therapy  

Microsoft Academic Search

PURPOSE. Verteporfin photodynamic therapy (PDT) is the most effective treatment for age-related macular degeneration, using laser activation of a photosensitizing dye to achieve closure of choroidal neovascularization. Although PDT preferentially af- fects pathologic vessels, it can also cause collateral damage to the overlying retina. In the current study, it was found that the neuroprotective agent brain-derived neurotrophic factor (BDNF) reduces

Daniel M. Paskowitz; George Nune; Douglas Yasumura; Haidong Yang; Robert B. Bhisitkul; Shivani Sharma; Michael T. Matthes; Marco A. Zarbin; Matthew M. LaVail; Jacque L. Duncan

2004-01-01

106

Photodynamic therapy influence on anti-cancer immunity  

NASA Astrophysics Data System (ADS)

The system of partial differential equations describing tumor-immune dynamics with angiogenesis taken into account is presented. For spatially homogeneous case, the steady state analysis of the model is carried out. The effects of single photodynamic impact are numerically simulated. In the case of strong immune response we found that the photodynamic therapy (PDT) gives rise to the substantial shrinkage of tumor size which is accompanied by the increase of IL-2 concentration. On the contrary, the photodynamic stimulation of weak immune response is shown to be insufficient to reduce the tumor. These findings indicate the important role of anti-cancer immune response in the long-term tumor control after PDT.

Isaeva, O. G.; Osipov, V. A.

2009-10-01

107

Anti-tumor effects on the combination of photodynamic therapy with arsenic compound in TC-1 cells implanted C57BL/6 mice  

NASA Astrophysics Data System (ADS)

The effects of As4O6 were studied as adjuvant on photodynamic therapy. As4O6 is considered to have anticancer activity via several biological actions such as free radical producing and inhibition of VEGF expression. In vitro experiments, cell proliferation and morphology were determined by MTT assay. Also, quantitative PCR array was performed to study the synergetic mechanism. Additionally, this study was supported by the finding that combination of photodynamic therapy and As4O6 shows an inhibition effect of tumor growth in C57BL/6 mice with TC-1 cells xenographs in vivo. Radachlorin and As4O6 significantly inhibited TC-1 cell proliferation in a dose-dependent manner (P < 0.05). Antiproliferative effect of combination treatment was significantly higher than those of TC-1 cells treated with either photodynamic therapy or As4O6 (62.4 and 52.5% decrease, respectively, compared to photodynamic therapy or As4O6 alone, P < 0.05). In addition, cell proliferation in combination of photodynamic therapy and As4O6 treatment significantly decreased by 77.4% compared to vehicle-only treated TC-1 cells (P < 0.05). Cell survival pathway (Naip1, Tert and Aip1) and p53-dependent pathway (Bax, p21Cip1, Fas, Gadd45, IGFBP-3 and Mdm-2) were markedly increased by combination treatment of photodynamic therapy and As4O6. Besides, the immunology response NEAT pathway (Ly- 12, CD178 and IL-2) also modulated after combination treatment of photodynamic therapy and As4O6. This combination effect apparently shows a same pattern in vivo model. These findings suggest the benefit of the combination treatment of photodynamic therapy and As4O6 for the inhibition of cervical cancer growth.

Lee, Kyu Wan; Wen, Lan Ying; Bae, Su Mi; Park, Choong Hak; Jeon, Woo Kyu; Lee, Doo Yun; Ahn, Woong Shick

2009-06-01

108

Photodynamic therapy for the treatment of non-small cell lung cancer  

PubMed Central

Photodynamic therapy is increasingly being utilized to treat thoracic malignancies. For patients with early-stage non-small cell lung cancer, photodynamic therapy is primarily employed as an endobronchial therapy to definitely treat endobronchial, roentgenographically occult, or synchronous primary carcinomas. As definitive monotherapy, photodynamic therapy is most effective in treating bronchoscopically visible lung cancers ?1 cm with no extracartilaginous invasion. For patients with advanced-stage non-small cell lung cancer, photodynamic therapy can be used to palliate obstructing endobronchial lesions, as a component of definitive multi-modality therapy, or to increase operability or reduce the extent of operation required. A review of the available medical literature detailing all published studies utilizing photodynamic therapy to treat at least 10 patients with non-small cell lung cancer is performed, and treatment recommendations and summaries for photodynamic therapy applications are described.

Simone, Charles B; Friedberg, Joseph S; Glatstein, Eli; Stevenson, James P; Sterman, Daniel H; Hahn, Stephen M; Cengel, Keith A

2012-01-01

109

Adjuvant therapy for atrial fibrillation.  

PubMed

Atrial fibrillation (AF) is the most common heart rhythm disorder, with increasing prevalence in the aging US population and affecting more than 2.3 million people. Current approaches for managing AF are rate- or rhythm-control strategies, both using anti-thrombotic therapy to prevent thromboembolism. While great advances have been made in understanding the pathophysiology of AF, few new strategies have shown promise in prevention or treatment of AF. Recent data suggest that non-antiarrhythmic medication may be useful in modifying the substrate that allows AF precipitation and perpetuation. This article reviews the data on the role of these agents in the prevention and management of AF as an adjunct to standard therapy. PMID:20014988

Mohammed, Khaja S; Kowey, Peter R; Musco, Simone

2010-01-01

110

Melanoma: Adjuvant therapy and other treatment options  

Microsoft Academic Search

Opinion statement  Melanoma, diagnosed and treated at its earliest stages, can be successfully cured by surgery alone. However, when metastatic\\u000a beyond the regional nodes, it is almost uniformly deadly. Adjuvant therapy targeted toward the treatment of microscopic residual\\u000a disease after surgical resection is the subject of intense scientific investigation because this is the stage at which it\\u000a is possible to have

Alicia Terando; Michael S. Sabel; Vernon K. Sondak

2003-01-01

111

Laser and Non-laser Light Sources for Photodynamic Therapy  

Microsoft Academic Search

.\\u000a \\u000a Photodynamic therapy (PDT) is an anticancer combination therapy, which requires a photosensitiser, which tends to accumulate\\u000a preferentially in the tumour, and light. Historically large, complex lasers have been used to carry out PDT treatment. Nowadays\\u000a there is a wide range of coherent and non-coherent sources that can be used. This paper considers the important characteristics\\u000a of light sources for

L. Brancaleon; H. Moseley

2002-01-01

112

Combined photodynamic therapy with verteporfin and intravitreal triamcinolone acetonide for choroidal neovascularization  

Microsoft Academic Search

PurposeTo examine combined photodynamic therapy (PDT) with verteporfin and intravitreal triamcinolone acetonide for choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD).

Richard F Spaide; John Sorenson; Leandro Maranan

2003-01-01

113

A look at clinical applications and developments of photodynamic therapy  

Microsoft Academic Search

The battle against cancer is so important that all possible weapons must be considered. Photodynamic therapy (PDT) is a therapeutic\\u000a approach which has proved its capacity to give many excellent results, but it is having some difficulty in being imposed.\\u000a The simplicity of the mechanism of action of this technique has been compromised by the multidisciplinary approach required\\u000a for its

Arménio Serra; Marta Pineiro; Nelson Pereira; António Rocha Gonsalves; Mafalda Laranjo; Margarida Abrantes; Filomena Botelho

2008-01-01

114

The effect of photodynamic therapy on tumor angiogenesis  

Microsoft Academic Search

Photodynamic therapy (PDT), the activation of a photosensitive drug in tumor tissue with light of specific wavelength, has\\u000a been used effectively to treat certain solid tumors. Though therapeutic responses are encouraging, PDT-mediated oxidative\\u000a stress can act as an angiogenic switch that ultimately leads to neovascularization and tumor recurrence. This article explores\\u000a the effect of PDT on angiogenesis in different tumor

Ramaswamy Bhuvaneswari; Yik Yuen Gan; Khee Chee Soo; Malini Olivo

2009-01-01

115

Ocular Photodynamic Therapy – Standard Applications and New Indications (Part 2)  

Microsoft Academic Search

Photodynamic therapy (PDT) has become a well-established treatment for vascular forms of age-related macular degeneration (AMD). The implementation of evidence-based medicine principles into the treatment regimen of AMD seems to be immensly important, since AMD continues to be the most frequent cause of blindness among patients older than 65 years in industrialized countries. Numerous randomized prospective studies demonstrated high levels

Stefan Mennel; Irene Barbazetto; Carsten H. Meyer; Silvia Peter; Michael Stur

2007-01-01

116

Photodynamic Therapy: A Means to Enhanced Drug Delivery to Tumors  

Microsoft Academic Search

Using the photosensitizer 2-(1-hexyloxyethyl)-2-devinyl pyropheophor- bide-a, we have determined that photodynamic therapy (PDT) can be used to facilitate the delivery of macromolecular agents. PDT regimens that use low fluences and fluence rates were the most successful. This effect was demonstrated for fluorescent microspheres with diameters ranging from 0.1 to 2 m. Such treatment given immediately before administration of Doxil, a

John W. Snyder; William R. Greco; David A. Bellnier; Lurine Vaughan; Barbara W. Henderson

2003-01-01

117

Interstitial photodynamic therapy in a rat liver metastasis model  

Microsoft Academic Search

Photodynamic therapy (PDT) of hepatic tumours has been restricted owing to the preferential retention of photosensitizers in liver tissue. We therefore investigated interstitial tumour illumination as a means of selective PDT. A piece of colon carcinoma CC531 was implanted in the liver of Wag\\/Rij rats. Photofrin was administered (5 mg kg-1 i.v.) 2 days before laser illumination. Tumours with a

R van Hillegersberg; JPA Marijnissen; WJ Kort; PE Zondervan; OT Terpstra; WM Star

1992-01-01

118

Photodynamic therapy of subfoveal choroidal neovascularization: clinical and angiographic examples  

Microsoft Academic Search

Background: Conventional photocoagulation of subfoveal choroidal neovascularization (CNV) is often accompanied by visual\\u000a loss due to thermal damage to adjacent retinal structures. Photodynamic therapy (PDT) allows vascular occlusion by selective\\u000a photochemical destruction of vascular endothelial cells only. In a pilot study we evaluated the use of PDT in CNV. Methods:\\u000a In a clinical phase I\\/II trial, patients with subfoveal CNV

Ursula Schmidt-Erfurth; Joan Miller; Michel Sickenberg; Arnd Bunse; Horst Laqua; Evangelos Gragoudas; Leonidas Zografos; Reginald Birngruber; Hubert van den Bergh; Andrew Strong; Ulrike Manjuris; Mario Fsadni; Bertrand Piguet; Neil M. Bressler

1998-01-01

119

Optical coherence tomography findings following photodynamic therapy of choroidal neovascularization  

Microsoft Academic Search

PURPOSE: To develop an optical coherence tomography (OCT) classification system that monitors the response of eyes treated with photodynamic therapy (PDT) with verteporfin for subfoveal choroidal neovascularization (CNV) from age-related macular degeneration (AMD).DESIGN: Retrospective interventional case series.METHODS: Ninety eyes (88 patients) with AMD and predominantly classic subfoveal CNV treated with PDT using verteporfin were identified by a laser log and

Adam H Rogers; Adam Martidis; Paul B Greenberg; Carmen A Puliafito

2002-01-01

120

Optical imaging in photodynamic therapy: mechanisms and applications  

NASA Astrophysics Data System (ADS)

Molecular excitation of photosensitizing agents provides reactive excited states, which can initiate chemical reactions, but it can also lead to molecular relaxation via radiative photophysical processes, providing the basis for fluorescence diagnostics. The best-known example of the former is Photodynamic Therapy (PDT), which is now approved for the treatment of a number of neoplastic and non-neoplastic pathologies. Although the concept of the use of photodynamic agents in diagnostics is as old as their use in therapy, the focused development of this aspect has been relatively recent. Typically, photodynamic agents have high triplet yields and relatively long triplet lifetimes (microsecond range), which allows them to interact and destroy molecular targets near them either directly or indirectly by producing other toxic molecular species. Associated with a high triplet yield is the fortunate attribute of most PDT agents in having low but finite fluorescence quantum yields. Fluorescence from these molecules may be used not only for diagnostics of disease de novo but also for guided surgery, PDT dosimetry and therapeutic monitoring. Other uses of fluorescence in PDT (not necessarily from the PDT agents) include the development of technologies that allow tracking of cells during treatment in vivo, studies of sub-cellular localization of molecules for mechanistic studies and photosensitizer tracking for specific targeting. An overview of studies on these aspects from different laboratories will be presented.

Solban, Nicolas; Georgakoudi, Irene; Ortel, Bernhard; Lin, Charles P.; Hasan, Tayyaba

2004-06-01

121

Intraoperative photodynamic therapy in laryngeal part of pharynx cancers  

NASA Astrophysics Data System (ADS)

In clinic intraoperative photodynamic therapy (IPT) was done in patients with primal squamous cells cancer of the laryngeal part of the pharynx. The He-Ne laser and methylene blue as a photosensibilizator were used. Cobalt therapy in the postoperative period was done in dose 45 Gr. Patients of control groups (1-th group) with only laser and (2-th group) only methylene blue were controlled during three years with the main group. The statistics show certain differences of recidives in the main group compared to the control groups. These facts are allowing us to recommend the use of IPT as an additional method in ENT-oncology diseases treatment.

Loukatch, Erwin V.; Trojan, Vasily; Loukatch, Vjacheslav

1996-12-01

122

A Comprehensive Tutorial on In Vitro Characterization of New Photosensitizers for Photodynamic Antitumor Therapy and Photodynamic Inactivation of Microorganisms  

PubMed Central

In vitro research performed on eukaryotic or prokaryotic cell cultures usually represents the initial step for characterization of a novel photosensitizer (PS) intended for application in photodynamic therapy (PDT) of cancer or photodynamic inactivation (PDI) of microorganisms. Although many experimental steps of PS testing make use of the wide spectrum of methods readily employed in cell biology, special aspects of working with photoactive substances, such as the autofluorescence of the PS molecule or the requirement of light protection, need to be considered when performing in vitro experiments in PDT/PDI. This tutorial represents a comprehensive collection of operative instructions, by which, based on photochemical and photophysical properties of a PS, its uptake into cells, the intracellular localization and photodynamic action in both tumor cells and microorganisms novel photoactive molecules may be characterized for their suitability for PDT/PDI. Furthermore, it shall stimulate the efforts to expand the convincing benefits of photodynamic therapy and photodynamic inactivation within both established and new fields of applications and motivate scientists of all disciplines to get involved in photodynamic research.

Maisch, Tim; Berneburg, Mark; Plaetzer, Kristjan

2013-01-01

123

Immune modulation using transdermal photodynamic therapy  

NASA Astrophysics Data System (ADS)

The photosensitizer benzoporphyrin derivative monoacid ring A (VerteporfinR or BPD) has maximum absorption characteristics (690 nm) and biodistribution characteristics which permit activation of the drug in capillaries of the skin without causing skin photosensitivity (transdermal PDT). This permits targeting of cells in the circulation for selective ablation. Since BPD has been shown to accumulate preferentially in activated lymphocytes and monocytes, studies have been undertaken to determine the effect of transdermal PDT on murine models for rheumatoid arthritis (the MRL/lpr adjuvant enhanced model) and multiple sclerosis (the experimental allergic encephalomyelitis (EAE) model in PL mice). Localized transdermal PDT with BPD was found to be completely successful in preventing the development of adjuvant enhanced arthritis in the MRL/lpr mouse as well as improving the underlying arthritic condition of these animals. In the EAE model, in which an adoptive transfer system was used, it was found that transdermal PDT of recipients was effective in preventing EAE if treatments were implemented up to 24 hours after cell transfer but was not effective if given later, indicating the requirement for circulating T cells for effective treatment.

Levy, Julia G.; Chowdhary, R. K.; Ratkay, Leslie; Waterfield, Douglas; Obochi, Modestus; Leong, Simon; Hunt, David W.; Chan, Agnes H.

1995-01-01

124

Agr function is upregulated by photodynamic therapy for Staphylococcus aureus and is related to resistance to photodynamic therapy.  

PubMed

Photodynamic therapy (PDT) has been considered a feasible alternative for antimicrobial therapy of multidrug-resistant pathogens. However, bacterial response mechanisms against PDT-generated photo-oxidative stress remain largely unknown. Herein, it is shown that the accessory gene regulator Agr is involved in Staphylococcus aureus response to photo-oxidative stress generated by laser-induced PDT with the photosensitizer chlorin e6 . Transcriptional profiling revealed that sublethal PDT induces a general stress response and also activates Agr-dependent gene regulation. Moreover, mutant S. aureus lacking Agr function showed hypersusceptibility to two independent PDT conditions with higher energy densities, demonstrating Agr-dependent S. aureus resistance against PDT. PMID:23668640

Park, Hee Jeong; Moon, Yeon-Hee; Yoon, Hyo-Eun; Park, Yoon Mee; Yoon, Jung-Hoon; Bang, Iel Soo

2013-08-01

125

Fractional Resurfacing Aiding Photodynamic Therapy of a Recalcitrant Plantar Verruca  

PubMed Central

Fractional resurfacing has become a very popular laser modality in recent years, and photodynamic therapy (PDT) has become a mainstay of many practices treating a wide array of clinical entities. In this case report, we describe a recalcitrant verrucous lesion on the foot that is unresponsive to cryotherapy, pulsed dye laser, and pulsed dye laser with PDT. The lesion did, however, respond very well to the use of a fractional laser to enhance the penetration of the PDT photosensitizer and then responded to pulsed dye laser with PDT. Fractional resurfacing prior to PDT may be a novel dermatologic treatment approach, making PDT an even better treatment option in the future.

Pope, Amy

2008-01-01

126

On molecular mechanism of the photodynamic therapy of tumors  

NASA Astrophysics Data System (ADS)

In this work we present the experimental results indicating that the photodestruction (inactivation) of glycolysis enzymes located in mitochondria and responsible for the energy providing of malignant tumors, could serve as a possible molecular mechanism of a photodynamic therapy of cancer. The formation of complexes between the glycolysis enzymes and sensitizer favors can lead to an effective photodestruction of the former [in the experiments lactate dehydrogenase (LDH), pyruvate kinase (PK), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and water-soluble tetra(carboxiphenyl)porphyrine [T(CP)P] (the analogue of coprorphyrin) were used as photosensitizer.

Mostovnikov, Vasili A.; Mostovnikova, Galina R.; Plavski, Vitali Y.; Tretjakov, S. A.

1995-01-01

127

Photodynamic Therapy Using Endogenous Photosensitization for Gastrointestinal Tumors  

PubMed Central

Photodynamic therapy (PDT) is a novel approach in the treatment of carcinomas of the gastrointestinal tract. This review defines PDT, discusses means of photosensitization and considers the mechanisms by which PDT causes cell death of the target tissue while at the same time avoid damage to normal tissues. Additional considerations include the time of PDT application, activation of the photosensitizer, effectiveness and toxicity of PDT, potential need for additional modalities of treatment and concludes with application of PDT principals to the early detection of malignancy. Data regarding the long term effectiveness of PDT for digestive tract adenocarcinomas are lacking because this field is still in its infancy.

Webber, John; Kessel, David; Fromm, David

1997-01-01

128

Optical dosimetry in photodynamic therapy of human uterus and brain  

NASA Astrophysics Data System (ADS)

Optical 'dose' is one of the fundamental parameters required in the design of an efficacious regimen of photodynamic therapy (PDT). The issues involved in delivering a sufficient optical dose to the human uterus and brain during PDT will be discussed. Specifically, measurements of optical properties and fluence rates in excised human uteri are presented. Measured fluence rates are compared to the predictions of a simple diffusion model and the clinical utility of the treatment is discussed. The delivery of light to brain tissue via a surgically implanted balloon applicator will also be considered. The time required to deliver and adequate dose is calculated based on known optical properties and diffusion theory.

Madsen, Steen J.; Svaasand, Lars O.; Hirschberg, Henry; Tadir, Yona; Tromberg, Bruce J.

1999-06-01

129

[Gorlin syndrome: photodynamic therapy, as a useful adjunct to surgery].  

PubMed

Gorlin syndrome, also called nevoid basal cell carcinoma syndrome, is well known by dermatologists. Since its onset, 10 years ago, photodynamic therapy has found new applications and is now currently used to cure single or multiple basal cell carcinomas, with good results and without residual scars. We recall some of the basic principles of this technique, as well as its indications in Gorlin syndrome, which we illustrate with one case. Plastic surgeons must consider this relatively new technique, developed by dermatologists, as a useful adjunct to surgery in the management of Gorlin syndrome. PMID:21907481

Huguier, V; Wierzbicka-Hainaut, E; Fray, J; Guillet, G; Dagrégorio, G

2011-09-09

130

Uniform irradiation of irregularly shaped cavities for photodynamic therapy  

NASA Astrophysics Data System (ADS)

It is difficult to achieve a uniform light distribution in irregularly shaped cavities. We have conducted a study on the use of hollow `integrating' moulds for more uniform light delivery of photodynamic therapy in irregularly shaped cavities such as the oral cavity. Simple geometries such as a cubical box, a sphere, a cylinder and a `bottle-neck' geometry have been investigated experimentally and the results have been compared with computed light distributions obtained using the `radiosity method'. A high reflection coefficient of the mould and the best uniform direct irradiance possible on the inside of the mould were found to be important determinants for achieving a uniform light distribution.

Rem, Alex I.; van Gemert, Martin J. C.; van der Meulen, Freerk W.; Gijsbers, Geert H. M.; Beek, Johan F.

1997-03-01

131

Photodynamic therapy of tumor-associated pathology of uterine cervix  

NASA Astrophysics Data System (ADS)

We have analyzed the results of photodynamic therapy using light-sensitizing agent "Photoheme" in 56 patients - 44 women with pre-cancerous lesions of cervix (group 1) and 12 women with early cervical cancer (group 2). The results were as follows: group 1 - c omplete regression - 3 7 ( 84%), p artial regression - 4 ( 9,%), s tabilization - 2 (4,6%), progression -1 (2,3%); group 2 - complete regression - 8 (66,7%), partial regression - 1 (8,3%), stabilization - 3 (25%). Anti-viral effect was registered in 38 (90,4%) cases after first procedure, in 4 cases - after second procedure.

Novikova, E. G.; Trushina, O. I.; Sokolov, V. V.; Filonenko, E. V.

2005-08-01

132

Uniform irradiation of irregularly shaped cavities for photodynamic therapy.  

PubMed

It is difficult to achieve a uniform light distribution in irregularly shaped cavities. We have conducted a study on the use of hollow 'integrating' moulds for more uniform light delivery of photodynamic therapy in irregularly shaped cavities such as the oral cavity. Simple geometries such as a cubical box, a sphere, a cylinder and a 'bottle-neck' geometry have been investigated experimentally and the results have been compared with computed light distributions obtained using the 'radiosity method'. A high reflection coefficient of the mould and the best uniform direct irradiance possible on the inside of the mould were found to be important determinants for achieving a uniform light distribution. PMID:9080537

Rem, A I; van Gemert, M J; van der Meulen, F W; Gijsbers, G H; Beek, J F

1997-03-01

133

Treatment of spontaneously occurring veterinary tumors with photodynamic therapy  

NASA Astrophysics Data System (ADS)

Chloroaluminum phthalocyanine tetrasulfonate was administered intravenously (1.0 mg/kg) to client owned cats and a dog with spontaneously occurring squamous cell carcinoma of head and neck. Light was delivered 48 hours post injection of the photosensitizer. An argon- pumped dye-laser was used to illuminate the lesions with 675 nm light delivered through a microlens fiber and/or a cylindrical diffuser. The light dose was 100 J/cm2 superficially or 300 J/cm interstitially. Eleven photodynamic therapy treatments in seven cats and one dog were performed. Two cats received a second treatment in approximately sixty days after the initial treatment. The superficial dose of light was increased to 200 J/cm2 for the second treatment. While the longest follow-up is twelve months, the responses are encouraging. The dog had a complete response. Among the cats, three showed complete response, three showed partial response and one showed no response. One cat expired two days post treatment. It is early to evaluate the response in two cats that received second treatments. Photodynamic therapy with chloroaluminum phthalocyanine tetrasulfonate was effective in treating squamous cell carcinoma in pet animals.

Panjehpour, Masoud; Legendre, Alfred; Sneed, Rick E.; Overholt, Bergein F.

1992-06-01

134

Upconversion Nanoparticles for Photodynamic Therapy and Other Cancer Therapeutics  

PubMed Central

Photodynamic therapy (PDT) is a non-invasive treatment modality for a variety of diseases including cancer. PDT based on upconversion nanoparticles (UCNPs) has received much attention in recent years. Under near-infrared (NIR) light excitation, UCNPs are able to emit high-energy visible light, which can activate surrounding photosensitizer (PS) molecules to produce singlet oxygen and kill cancer cells. Owing to the high tissue penetration ability of NIR light, NIR-excited UCNPs can be used to activate PS molecules in much deeper tissues compared to traditional PDT induced by visible or ultraviolet (UV) light. In addition to the application of UCNPs as an energy donor in PDT, via similar mechanisms, they could also be used for the NIR light-triggered drug release or activation of 'caged' imaging or therapeutic molecules. In this review, we will summarize the latest progresses regarding the applications of UCNPs for photodynamic therapy, NIR triggered drug and gene delivery, as well as several other UCNP-based cancer therapeutic approaches. The future prospects and challenges in this emerging field will be also discussed.

Wang, Chao; Cheng, Liang; Liu, Zhuang

2013-01-01

135

Initiation of Apoptosis and Autophagy by Photodynamic Therapy  

PubMed Central

This study was designed to examine modes of cell death after photodynamic therapy (PDT). Murine leukemia L1210 cells and human prostate Bax-deficient DU-145 cells were examined after PDT-induced photodamage to the endoplasmic reticulum (ER). Previous studies indicated that this treatment resulted in a substantial loss of Bcl-2 function. Both apoptosis and autophagy occurred in L1210 cells after ER photodamage with the latter predominating after 24 hr. These processes were characterized by altered cellular morphology, chromatin condensation, loss of mitochondrial membrane potential and formation of vacuoles containing cytosolic components. Western blots demonstrated processing of LC3-I to LC3-II, a marker for autophagy. In DU145 cells, PDT initiated only autophagy. Phosphatidylinositol (PI) 3-kinase inhibitors suppressed autophagy in both cell lines as indicated by inhibition of vacuolization and LC3 processing. Inhibitors of apoptosis and/or autophagy were then used to delineate the contributions of the two pathways to the effects of PDT. Given the ability of autophagy to upregulate MHC-11 peptide presentation, autophagy may play a role in the ability of photodynamic therapy to stimulate immunologic recognition of target cells.

Kesse, David; Vicente, M. Graca H.; Reiners, John J.

2009-01-01

136

Light-emitting diode source for photodynamic therapy  

NASA Astrophysics Data System (ADS)

Lasers have traditionally been the preferred light source for activation of the photosensitizing agents used in photodynamic therapy (PDT). Their monochromaticity, high power, and the ability to couple that high power into optical fibers have dictated their use. There are however, many potential applications for PDT which do not require fiberoptic light delivery, and thus, need not incur the high cost associated with the use of laser systems. Treatment of skin cancer, cervical cancer, and cancers in the oral cavity could be effectively treated with alternative light sources, which would greatly reduce the cost of treatment. This paper will describe the features of a preclinical light emitting diode (LED) based source for photodynamic therapy, designed and built by PDT Systems. The results of an animal study, using the photosensitizer SnET2 activated at 660 nm, which compared the efficacy of PDT performed with a dye laser system with that of the LED system will be presented. Future plans for a clinical version of the LED system will also be discussed.

Lytle, A. Charles; Dalton, Brian K.; Doiron, Daniel R.; Keck, Rick W.; Selman, Steven H.; Wagoner, Miriam E.

1993-06-01

137

Guidelines for topical photodynamic therapy: report of a workshop of the British Photodermatology Group  

Microsoft Academic Search

Summary Topical photodynamic therapy (PDT) is effective in the treatment of certain non-melanoma skin cancers and is under evaluation in other dermatoses. Its development has been enhanced by a low rate of adverse events and good cosmesis. 5-Aminolaevulinic acid (ALA) is the main agent used, converted within cells into the photosensitizer protoporphyrin IX, with surface illumination then triggering the photodynamic

C. A. Morton; S. B. Brown; S. Collins; S. Ibbotson; H. Jenkinson; H. Kurwa; K. Langmack; K. Mckenna; H. Moseley; A. D. Pearse; M. Stringer; D. K. Taylor; G. Wong; L. E. Rhodes

2002-01-01

138

Monitoring photodynamic therapy of localized infections by bioluminescence imaging of genetically engineered bacteria  

Microsoft Academic Search

The increasing occurrence of multi-antibiotic resistant microbes has led to the search for alternative methods of killing pathogens and treating infections. Photodynamic therapy (PDT) uses the combination of non-toxic dyes and harmless visible light to produce reactive oxygen species that can kill mammalian and microbial cells. Although the photodynamic inactivation of bacteria has been known for over a hundred years,

Tatiana N Demidova; Faten Gad; Touqir Zahra; Kevin P Francis; Michael R Hamblin

2005-01-01

139

Photodynamic therapy and the treatment of malignancies of the head and neck  

NASA Astrophysics Data System (ADS)

Seventy-nine patients with neoplastic diseases of the larynx, oral cavity, pharynx, and skin have been treated with photodynamic therapy (PDT) with follow-up to 65 months. Patients with carcinoma-in-situ (CIS) and T1 carcinomas obtained a complete response after one PDT treatment. All but two patients remain free of disease. Four patients with T2 and T3 superficial carcinomas were treated with PDT. One patient developed recurrence with 51- month follow-up. Eleven patients with deeply invasive T2, T3, and T4 carcinomas were treated with PDT. Of those eleven, eight obtained a complete response, but five have recurred locally. A response can be achieved with PDT, although not a consistent complete response because of the depth of invasion of the tumor. This is due to the inability to adequately deliver laser light to the depths of the tumor bed. Eight patients with massive neck recurrences of squamous cell carcinomas were treated with intraoperative adjuvant PDT following tumor resection. Only one patient developed recurrence with 30-month follow-up. PDT is highly effective for the curative treatment of early carcinomas (CIS, T1) of the head and neck. T2 and T3 superficial carcinomas, with invasion less than 0.5 cm, are also curatively treated with PDT with significantly reduced morbidity compared to conventional modes of treatment. Also, intraoperative adjuvant PDT may increase cure rates of large infiltrating carcinomas of the head and neck.

Biel, Merrill A.; Boss, Ellen E.

1996-04-01

140

Photodynamic therapy using Photofrin and Foscan and the treatment of malignancies of the head and neck  

NASA Astrophysics Data System (ADS)

One hundred thirty patients with neoplastic diseases of the larynx, oral cavity, pharynx and skin have been treated with photodynamic therapy (PDT) with follow-up to 79 months. Those patients with primary or recurrent leukoplakia, carcinoma-in- situ (CIS) and T1 carcinomas obtained a complete response after one PDT treatment and 87% remain free of disease. Sixteen patients with deeply invasive T2 and T3 carcinomas were treated with PDT. Of those sixteen, ten obtained a complete response, but six have recurred locally. Although a response can be achieved with PDT in the larger solid tumors, it is not a consistent complete response because of the depth of invasion of the tumor. This is due to the inability to adequately deliver laser light to the depths of the tumor bed. Fourteen patients with massive recurrences of squamous cell carcinomas were treated with intraoperative adjuvant PDT following tumor resection. Two patients developed a local recurrence within the field of treatment. PDT is highly effective for the curative treatment of early carcinomas (CIS, T1) of the head and neck. T2 and T3 superficial carcinomas, with invasion less than 0.5 cm, are also curatively treated with PDT with significantly reduced morbidity compared to conventional modes of treatment. Also, intraoperative adjuvant PDT may increase cure rates of large infiltrating carcinomas of the head and neck.

Biel, Merrill A.

1998-05-01

141

Autologous bone marrow transplantation by photodynamic therapy  

NASA Astrophysics Data System (ADS)

Simultaneous exposure of Merocyanine 540 dye containing cultured tumor cells to 514-nm laser light (93.6 J/cm2) results in virtually complete cell destruction. Under identical conditions, 40% of the normal progenitor (CFU-GM) cells survive the treatment. Laser- photoradiation treated, cultured breast cancer cells also were killed, and living tumor cells could not be detected by clonogenic assays or by anti-cytokeratin monoclonal antibody method. Thus, laser photoradiation therapy could be useful for purging of contaminating tumor cells from autologous bone marrow.

Gulliya, Kirpal S.

1992-06-01

142

Photodynamic therapy for Barrett's esophagus: effect of steroid therapy on stricture formation  

NASA Astrophysics Data System (ADS)

The primary goal of this study was to investigate whether the use of oral steroids would reduce the incidence of stricture formation after balloon photodynamic therapy in patients with dysplasia and early caner in Barrett's esophagus. The effect of other treatment parameters such as light dose and multiple treatments were also investigated.

Panjehpour, Masoud; Overholt, Bergein F.; Haydek, John M.; Lee, Sharon G.

1999-07-01

143

Photodynamic therapy in the treatment and diagnosis of cancers: a sixty-case report  

NASA Astrophysics Data System (ADS)

This 60-case report deals with the application of photodynamic therapy in the treatment and diagnosis of cancer. The application of photodynamic therapy in the treatment and diagnosis of cancer is a development from the late seventies. Since March 1989, we have diagnosed and treated 60 cancer patients with this therapy. Our results show that the positive rate in diagnosis is 100 percent, the effective rate in treatment is 75 percent.

Wang, Kang-Jun; Shi, Weng-Jun; Gong, Huai-Nang; Zhan, Xi-De; Li, Zhi-Jian

1993-03-01

144

Photodynamic therapy for gynecological diseases and breast cancer.  

PubMed

Photodynamic therapy (PDT) is a minimally invasive and promising new method in cancer treatment. Cytotoxic reactive oxygen species (ROS) are generated by the tissue-localized non-toxic sensitizer upon illumination and in the presence of oxygen. Thus, selective destruction of a targeted tumor may be achieved. Compared with traditional cancer treatment, PDI has advantages including higher selectivity and lower rate of toxicity. The high degree of selectivity of the proposed method was applied to cancer diagnosis using fluorescence. This article reviews previous studies done on PDT treatment and photodetection of cervical intraepithelial neoplasia, vulvar intraepithelial neoplasia, ovarian and breast cancer, and PDT application in treating non-cancer lesions. The article also highlights the clinical responses to PDT, and discusses the possibility of enhancing treatment efficacy by combination with immunotherapy and targeted therapy. PMID:23691448

Shishkova, Natashis; Kuznetsova, Olga; Berezov, Temirbolat

2012-03-01

145

Laser and non-laser light sources for photodynamic therapy.  

PubMed

Photodynamic therapy (PDT) is an anticancer combination therapy, which requires a photosensitiser, which tends to accumulate preferentially in the tumour, and light. Historically large, complex lasers have been used to carry out PDT treatment. Nowadays there is a wide range of coherent and non-coherent sources that can be used. This paper considers the important characteristics of light sources for PDT, including dye lasers pumped by argon or metal vapour lasers and frequency-doubled Nd:YAG lasers. Non-laser sources including tungsten filament, xenon arc, metal halide and fluorescent lamps are also discussed. New exciting developments such as LEDs and femtosecond lasers are also reviewed. The relative merits of laser and non-laser sources are critically examined. PMID:12181632

Brancaleon, L; Moseley, H

2002-01-01

146

New approaches to the adjuvant therapy of colon cancer.  

PubMed

Analysis of data from patients treated outside clinical trials suggests that adjuvant chemotherapy for stage II colon cancer provides less than a 3% absolute improvement in survival at 5 years. This is remarkably close to the small degree of benefit suggested by controlled studies. An overview of the data suggests that surgery alone cures approximately 75% of stage II patients. Between 20% and 25% of patients experience disease recurrence despite surgery and adjuvant chemotherapy, whereas adjuvant chemotherapy cures between 1% and 6%. In stage III patients, the benefit of adjuvant therapy is greater overall. The extent of benefit relates to tumor grade, invasion, and nodal involvement. Incorporation of molecular markers in the design of current trials may enable us to refine our identification of patients at highest risk of recurrence and hence those standing to gain most from adjuvant therapy. PMID:17030637

Benson, Al B

2006-10-01

147

Are adjuvant therapies for tonsillectomy evidence based?  

PubMed

Our aim was to ascertain the current practice of adjuvant therapy for tonsillectomy and to determine whether it is evidence based. Anonymized postal questionnaires were sent to all UK otolaryngology consultants registered with the specialty association, and a literature search was performed using relevant search terms in all possible combinations. Among the responders there was little enthusiasm for routine intra-operative local anaesthesia, post-operative topical benzydamine hydrochloride (Difflam) spray or post-operative antibiotics. This is consistent with the lack of robust evidence to support any of these practices. Paracetamol (acetaminophen) is prescribed by almost 90 per cent for post-operative analgesia, and the current literature supports its efficacy and safety. Further, most practitioners combine paracetamol with opioids and/or non-steroidal anti-inflammatory drugs (NSAIDs). Evidence to support the additional use of these agents is, however, non-existent or limited. Some aspects of tonsillectomy care are uniform and evidence based. Others are heterogeneous and suffer from lack of adequate data in the literature. PMID:16102216

Dhiwakar, M; Brown, P M

2005-08-01

148

Simultaneous two-photon excitation of photodynamic therapy agents  

NASA Astrophysics Data System (ADS)

The spectroscopic and photochemical properties of several photosensitive compounds are compared using conventional single-photon excitation (SPE) and simultaneous two-photon excitation (TPE). TPE is achieved using a mode-locked titanium:sapphire laser, the near infrared output of which allows direct promotion of non-resonant TPE. Excitation spectra and excited state properties of both type I and type II photodynamic therapy (PDT) agents are examined. In general, while SPE and TPE selection rules may be somewhat different, the excited state photochemical properties are equivalent for both modes of excitation. In vitro promotion of a two-photon photodynamic effect is demonstrated using bacterial and human breast cancer models. These results suggest that use of TPE may be beneficial for PDT, since the technique allows replacement of visible or ultraviolet excitation with non- damaging near infrared light. Further, a comparison of possible excitation sources for TPE indicates that the titanium:sapphire laser is exceptionally well suited for non- linear excitation of PDT agents in biological systems due to its extremely short pulse width and high repetition rate; these features combine to effect efficient PDT activation with minimal potential for non-specific biological damage.

Wachter, Eric A.; Partridge, William P.; Fisher, Walt G.; Dees, H. C.; Petersen, Mark G.

1998-07-01

149

ALA-Butyrate prodrugs for Photo-Dynamic Therapy  

NASA Astrophysics Data System (ADS)

The use of 5-aminolevulinic acid (ALA) administration has led to many applications of photodynamic therapy (PDT) in cancer. However, the hydrophilic nature of ALA limits its ability to penetrate the cells and tissues, and therefore the need for ALA derivatives became an urgent research target. In this study we investigated the activity of novel multifunctional acyloxyalkyl ester prodrugs of ALA that upon metabolic hydrolysis release active components such as, formaldehyde, and the histone deacetylase inhibitory moiety, butyric acid. Evaluation of these prodrugs under photo-irradiation conditions showed that butyryloxyethyl 5-amino-4-oxopentanoate (ALA-BAC) generated the most efficient photodynamic destruction compared to ALA. ALA-BAC stimulated a rapid biosynthesis of protoporphyrin IX (PpIX) in human glioblastoma U-251 cells which resulted in generation of intracellular ROS, reduction of mitochondrial activity, leading to apoptotic and necrotic death of the cells. The apoptotic cell death induced by ALA / ALA-BAC followed by PDT equally activate intrinsic and extrinsic apoptotic signals and both pathways may occur simultaneously. The main advantage of ALA-BAC over ALA stems from its ability to induce photo-damage at a significantly lower dose than ALA.

Berkovitch, G.; Nudelman, A.; Ehenberg, B.; Rephaeli, A.; Malik, Z.

2010-05-01

150

Photodynamic therapy of subfoveal choroidal neovascularization with verteporfin in the ocular histoplasmosis syndrome  

Microsoft Academic Search

ObjectiveTo evaluate the safety and effect on visual acuity of photodynamic therapy with verteporfin (Visudyne, Novartis AG) in patients with subfoveal choroidal neovascularization (CNV) secondary to the ocular histoplasmosis syndrome (OHS).

David A Saperstein; Philip J Rosenfeld; Neil M Bressler; Robert H Rosa; Michel Sickenberg; Paul Sternberg; Thomas M Aaberg; Troy A Reaves

2002-01-01

151

Photodynamic therapy with verteporfin in ocular histoplasmosis: Uncontrolled, open-label 2-year study  

Microsoft Academic Search

ObjectiveTo evaluate the safety, effect on visual function, and fluorescein angiographic appearance of subfoveal choroidal neovascularization (CNV) through 2 years after photodynamic therapy with verteporfin (Visudyne; Novartis AG, Basel, Switzerland) in patients with ocular histoplasmosis syndrome (OHS).

Philip J. Rosenfeld; David A. Saperstein; Neil M. Bressler; Troy A. Reaves; Michel Sickenberg; Robert H. Rosa; Paul Sternberg; Thomas M. Aaberg

2004-01-01

152

A case of presumed choroidal metastasis from carcinoid tumor treated by photodynamic therapy with verteporfin  

PubMed Central

We report a case of metastatic choroidal carcinoid tumor with favorable outcome after photodynamic therapy. A 75-year-old woman was presumptively diagnosed with bilateral choroidal metastases from carcinoid tumor. Although the tumor in the right eye showed a tendency toward rapid expansion and required aggressive treatment to preserve vision, the size was still small and we hesitated to use external-beam radiotherapy because of the risk of radiation retinopathy. Consequently, photodynamic therapy was performed on the right eye, resulting in drastic reduction of the size and height of the choroidal tumor. Good visual acuity was maintained after photodynamic therapy. Photodynamic therapy may be an effective treatment for choroidal metastasis from carcinoid tumor.

Kawakami, Setsuko; Wakabayashi, Yoshihiro; Goto, Hiroshi

2013-01-01

153

Photodynamic Therapy of Human Malignant Melanoma Xenografts in Athymic Nude Mice,  

National Technical Information Service (NTIS)

While photodynamic therapy (PDT) for cutaneous malignancies including dermal recurrences of breast cancer and basal cell carcinomas has shown great promise, PDT of malignant melanoma has remained incompletely understood. A comparison study of the effects ...

J. S. Nelson J. L. McCullough M. W. Berns

1981-01-01

154

Treatment considerations for photodynamic therapy in the cat  

NASA Astrophysics Data System (ADS)

The process of photodynamic therapy (PDT) and its application for the treatment of cancer has been reported for veterinary patients. Multiple factors function together in the patient to influence the overall effectiveness of a PDT treatment. All of these factors need to be considered in evaluating a patient for possible PDT treatment, reviewing the design and results of any PDT clinical trial, and in proposing alterations to the approach of the clinical application of PDT where improvement of results is desired. The use of PDT has been reported several times for the treatment of facial, solar-induced squamous cell carcinoma (SCC) in cats. From our clinical experiences in employing chloro-aluminum sulfonated phthalocyanine (AlPcS) for this condition in cats and in comparing our experiences to those of others, we are attempting to better understand this disease and the factors which could influence the effectiveness of PDT for its treatment.

Peavy, George M.; Krasieva, Tatiana; Tromberg, Bruce J.; Berns, Michael W.

1994-09-01

155

Mechanisms of vessel damage in photodynamic therapy (Invited Paper)  

NASA Astrophysics Data System (ADS)

Vessel constriction and platelet aggregation are observed within the first minutes of light exposure to photosensitized tissues and lead to blood flow stasis, tissue hypoxia, and nutrient depravation. The mechanism for these vessel changes remains unknown, although the release of eicosanoids is implicated. We propose the following hypothesis: Photodynamic therapy results in specific perturbations of endothelial cells which results in a combination of membrane damage, mitochondrial damage, and rearrangement of cytoskeletal proteins. This results in cellular stress which leads to interruption of tight junctions along the endothelium and cell rounding. Cell rounding exposes the basement membrane proteins causing activation of platelets and leukocytes. Activated platelets and leukocytes release thromboxane and other eicosanoids. These eicosanoids induce vasoconstriction, platelet aggregation, increases in vessel permeability, and blood flow stasis.

Fingar, Victor H.; Wieman, T. J.

1992-06-01

156

Chemiluminescence detection of reactive oxygen species during photodynamic therapy  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) utilizes photon energy to activate a pre-administered photosensitizer drug in tissue to achieve a localized tumor control. PDT cell killing mechanism is directly related to the reactive oxygen species (ROS) produced during the photochemical reactions. Conventional PDT dosimetry evaluates distributions of the photosensitizer drug, photon propagation and absorption, and availability of molecular oxygen in the target tissue. Yet, the ultimate bullet for the damaging effect is ROS. An evaluation of ROS production during PDT should provide a more direct marker for PDT. Fluoresceinyl Cypridina Luciferin Analog (FCLA) is a chemiluminescence probe that specifically interacts with ROS (singlet oxygen and/or superoxide). The work is a preliminary investigation of the feasibility using FCLA as a means to evaluate ROS production in PDT.

Xing, Da; Qin, Yanfang; Wu, Yunxia; Zhou, Jin; Luo, Shiming; He, Yonghong; Chen, Qun

2004-06-01

157

Enhancing antibiofilm efficacy in antimicrobial photodynamic therapy: effect of microbubbles  

NASA Astrophysics Data System (ADS)

In this study, we tested the hypothesis that a microbubble containing photosensitizer when activated with light would enable comprehensive disinfection of bacterial biofilms in infected root dentin by antimicrobial photodynamic therapy (APDT). Experiments were conducted in two stages. In the stage-1, microbubble containing photosensitizing formulation was tested for its photochemical properties. In the stage-2, the efficacy of microbubble containing photosensitizing formulation was tested on in vitro infected root canal model, developed with monospecies biofilm models of Enterococcus faecalis on root dentin substrate. The findings from this study showed that the microbubble containing photosensitizing formulation was overall the most effective formulation for photooxidation, generation of singlet oxygen, and in disinfecting the biofilm bacteria in the infected root canal model. This modified photosensitizing formulation will have potential advantages in eliminating bacterial biofilms from infected root dentin.

Kishen, Anil; George, Saji

2013-02-01

158

Benzoporphyrins as photosenitizers for the photodynamic therapy of cancer  

NASA Astrophysics Data System (ADS)

A family of benzoporphyrins formed by differently substituted metallo tetrabenzoporphyrins and one opp-dibenzoporphyrin has been prepared. The former benzoporphyrins, and meso- tetra(m-hydroxy-phenyl)chlorin (m-THPC) to act as reference, have been encapsulated into liposomes and subjected to preliminary in vitro and in vivo assays to test their efficacy as photosensitizers in the photodynamic therapy of cancer. The results of the photocytotoxicity test shows that, with the exception of the nickel complexes 5, and 7/8, the other porphyrins are photobiologically active, the Mg-tetrabenzoporphyrin 1 and the opp-dibenzoporphyrin 10 being the most active. The dark toxicity of the photoactive porphyrins is in the range described for many photosensitizers, including HPD. The in vivo assays show no toxicity in the liver for any of the compounds tested, and also that 2 is the most promising photosensitizer among them, because of an efficient localization in an experimental mouse tumor.

Valles, Ascuncion; Biolo, Roberta; Bonnett, Raymond; Canete, Magdalena; Gomez, Antonia M.; Jori, Giulio; Juarranz, Angeles; McManus, Kimberly A.; Okolo, Kawulia T.; Soncin, M.; Villanueva, Angeles

1996-01-01

159

Endoscopic photodynamic therapy of tumors using gold vapor laser  

NASA Astrophysics Data System (ADS)

Compact sealed-off gold vapor laser (GVL) with 2 W average power and 628 nm wavelength was used for endoscopic photodynamic therapy in 20 patients with different tumors in respiratory system and upper gastrointestinal tract. Russian-made hematoporphyrin derivative (Hpd) `Photohem' was used as a photosensitizer. It was given intravenously at a dose of 2 - 2.5 mg/kg body weight 48 hours prior to tumor illumination with 628 nm light from GVL. Intermittent irradiation with GVL was done through flexible endoscope always under local anaesthesia at a power of 200 - 400 mW/sm2 and a dose of 150 - 400 J/sm2. 80% patients showed complete or partial response depending on stage of tumor. In cases of early gastric cancer all patients had complete remission with repeated negative biopsies. No major complication occurred.

Kuvshinov, Yury P.; Poddubny, B. K.; Mironov, Andrei F.; Ponomarev, Igor V.; Shental, V. V.; Vaganov, Yu. E.; Kondratyeva, T. T.; Trofimova, E. V.

1996-01-01

160

Monitoring oxygen concentration during photodynamic therapy using prompt photosensitizer fluorescence.  

PubMed

A novel technique is described that uses either time-resolved or steady state prompt photosensitizer fluorescence to measure local oxygen concentration. Solution experiments conducted with Al(III) phthalocyanine chloride tetrasulfonic acid confirmed that the steady state fluorescence signal is dependent on the oxygen concentration and fluence rate. A relationship between prompt sensitizer fluorescence and sensitizer triplet quenching efficiency is derived which does not require knowledge of the Stern-Volmer constant. Similar relationships are also derived for sensitizer delayed fluorescence and phosphorescence. An explicit photodynamic therapy (PDT) dose metric that incorporates light dosimetry, sensitizer dosimetry, and triplet quenching efficiency is introduced. All components of this metric can be determined by optical measurements. PMID:24051952

Weston, Mark A; Patterson, Michael S

2013-09-20

161

Effects of photodynamic therapy on human glioma spheroids  

NASA Astrophysics Data System (ADS)

The poor prognosis for patients with malignant brain neoplasm has led to a search for better treatment modalities. Although gliomas are considered to be disseminated tumors in the brain, most recur at the site of the previous tumor resection. Improved local control would thus be of clear benefit. The utility of photodynamic therapy (PDT) in the treatment of brain neoplasms is investigated using a human glioma spheroid model. Specifically, the effects of PDT on human glioma spheroids are investigated using PhotofrinTM and 56-aminolevulinic acid (ALA). The effects of various irradiation schemes were monitored using a simple growth assay. A growth delay was observed at an optical fluence of approximately 35 J cm-2 for spheroids incubated in Photofrin. Spheroids incubated in ALA were unaffected by the PDT treatment regimens examined in this study. This was most likely a result of inadequate photosensitizer concentration.

Madsen, Steen J.; Sun, Chung-Ho; Chu, Eugene A.; Hirschberg, Henry; Tromberg, Bruce J.

1999-07-01

162

[Experimental bases for photodynamic laser therapy in chronic polyarthritis].  

PubMed

The principle of photodynamic laser therapy (PDT) for chronic polyarthritis consists in specifically concentrating a drug (photosensitizer) in the synovium. Subsequent activation of the photosensitizer by means of laser leads to a cytotoxic effect. The practicability of PDT was first shown in cell cultures of human synovial fibroblasts. For further tests an animal model consisting of IgG-induced arthritis in rabbits was used. In this model, concentration of the photosensitizer in the synovial lining cells, in the media of arteries and in the lymphoid infiltrate was seen. After laser irradiation there was total selective demarcation of the synovium. In contrast, bradytrophic tissues such as cartilage, meniscus and ligament structures were changed neither macroscopically nor microscopically. In the animal model PDT combines high selectivity with minimal invasiveness and can be used in small joints. PDT thus offers ideal preconditions for future minimal invasive treatment of chronic inflammatory joint diseases. PMID:8622843

Hendrich, C; Hüttmann, G; Diddens, H; Seara, J; Siebert, W E

1996-02-01

163

Photodynamic therapy of head and neck cancer with different sensitizers  

NASA Astrophysics Data System (ADS)

This paper deals with the results of clinical trials for sulfated aluminum phthalocyanine (PHS) (Photosens, Russia) and Photogeme (PG) in Russia. The results of photodynamic therapy (PDT) of head and neck tumors (HNT), side effects and ways of their correction and prevention, as well as possibility to work out less toxic regimes of PDT with photosense, choice of laser and type of irradiation are discussed. PDT have been provided in 79 patients with different head and neck tumors. Efficacy of PDT depended on tumor size and its histological type. Undesirable changes in plasma content of antioxidants by means of high pressure liquid chromatography (HLPC) have been found in patients after PHS injection. Influence of short-term and long-term supplementation with beta-carotene and vitamin E on this parameters are discussed.

Vakoulovskaia, Elena G.; Chental, Victor V.; Abdoullin, N. A.; Kuvshinov, Yury P.; Tabolinovskaia, T. D.; Edinak, N. J.; Poddubny, Boris K.; Kondratjeva, T. T.; Meerovich, Gennady A.; Stratonnikov, Alexander A.; Linkov, Kirill G.; Agafonov, V. V.

1997-12-01

164

Current Status of Photodynamic Therapy for Bile Duct Cancer  

PubMed Central

The most common form in bile duct cancers is a highly desmoplastic cancer with a growth pattern characterized by periductal extension and infiltration. The prognosis of bile duct cancers, especially hilar cholangiocarcinoma, is limited by tumor spread along the biliary tree leading to refractory obstructive cholestasis, cholangitis, and liver failure. Although biliary endoprosthesis improves occlusion rates and reduces the number of therapeutic interventions, median survival time is not ameliorated. Photodynamic therapy (PDT) is a local photochemical tumor treatment that consists of a photosensitizing agent in combination with laser irradiation of a distinct wavelength. Tumor ablation with PDT combined with biliary stenting reduces cholestasis and significantly improves median survival time in selected patients with bile duct cancers.

Lee, Tae Yoon; Shim, Chan Sup

2013-01-01

165

Photodynamic therapy of cancer with the photosensitizer PHOTOGEM  

NASA Astrophysics Data System (ADS)

The first clinical trials of photodynamic therapy (PDT) in Russia were started in P. A. Hertzen Moscow Research Oncology Institute in October of 1992. Up to now, 61 patients with primary or recurrent malignant tumors of the larynx (3), trachea (1), bronchus (11), nose (1), mouth (3), esophagus (12), vagina and uterine cervix (3), bladder (2), skin (6), and cutaneous and subcutaneous metastases of breast cancer and melanomas (6) have been treated by PDT with the photosensitizer Photogem. At least partial tumor response was observed in all of the cases, but complete remission indicating no evident tumors has been reached in 51% of the cases. Among 29 patients with early and first stage cancer 14 patients had multifocal tumors. Complete remission of tumors in this group reached 86%.

Sokolov, Victor V.; Chissov, Valery I.; Filonenko, E. V.; Sukhin, Garry M.; Yakubovskaya, Raisa I.; Belous, T. A.; Zharkova, Natalja N.; Kozlov, Dmitrij N.; Smirnov, V. V.

1995-01-01

166

TOPICAL REVIEW: The physics, biophysics and technology of photodynamic therapy  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) uses light-activated drugs to treat diseases ranging from cancer to age-related macular degeneration and antibiotic-resistant infections. This paper reviews the current status of PDT with an emphasis on the contributions of physics, biophysics and technology, and the challenges remaining in the optimization and adoption of this treatment modality. A theme of the review is the complexity of PDT dosimetry due to the dynamic nature of the three essential components—light, photosensitizer and oxygen. Considerable progress has been made in understanding the problem and in developing instruments to measure all three, so that optimization of individual PDT treatments is becoming a feasible target. The final section of the review introduces some new frontiers of research including low dose rate (metronomic) PDT, two-photon PDT, activatable PDT molecular beacons and nanoparticle-based PDT.

Wilson, Brian C.; Patterson, Michael S.

2008-05-01

167

Systemic estimation of the effect of photodynamic therapy of cancer  

NASA Astrophysics Data System (ADS)

The effects of photodynamic therapy (PDT) of cancer needs objective estimation and its unification in experimental as well as in clinical studies. They must include not only macroscopical changes but also the complex of following morphological criteria: (1) the level of direct tumor damage (direct necrosis and apoptosis); (2) the level of indirect tumor damage (ischemic necrosis); (3) the signs of vascular alterations; (4) the local and systemic antiblastome resistance; (5) the proliferative activity and malignant potential of survival tumor tissue. We have performed different regimes PDT using phthalocyanine derivatives. The complex of morphological methods (Ki-67, p53, c-myc, bcl-2) was used. Obtained results showed the connection of the tilted morphological criteria with tumor regression.

Kogan, Eugenia A.; Meerovich, Gennady A.; Torshina, Nadezgda L.; Loschenov, Victor B.; Volkova, Anna I.; Posypanova, Anna M.

1997-12-01

168

Transient Increased Exudation after Photodynamic Therapy of Intraocular Tumors  

PubMed Central

To report transient increased exudation after photodynamic therapy (PDT) of three different intraocular tumors (retinal hemangioblastoma, retinal astrocytoma, amelanotic choroidal melanoma). PDT with verteporfin (6 mg/m2 body surface area) was delivered at a dose of 50 J/cm2 and intensity of 600 mW/cm2 over 83 s. All patients experienced decreased vision within a few days following PDT. Optical coherence tomography showed development of subfoveal fluid in all cases and noncystoid intraretinal edema in the eye with juxtapapillary retinal hemangioblastoma. There was complete absorption of retinal/subretinal fluid with improvement of visual acuity to 20/20 in all cases between 3 weeks to 4 months after PDT.

Mashayekhi, Arman; Shields, Carol L.; Shields, Jerry A.

2013-01-01

169

Monitoring oxygen concentration during photodynamic therapy using prompt photosensitizer fluorescence  

NASA Astrophysics Data System (ADS)

A novel technique is described that uses either time-resolved or steady state prompt photosensitizer fluorescence to measure local oxygen concentration. Solution experiments conducted with Al(III) phthalocyanine chloride tetrasulfonic acid confirmed that the steady state fluorescence signal is dependent on the oxygen concentration and fluence rate. A relationship between prompt sensitizer fluorescence and sensitizer triplet quenching efficiency is derived which does not require knowledge of the Stern-Volmer constant. Similar relationships are also derived for sensitizer delayed fluorescence and phosphorescence. An explicit photodynamic therapy (PDT) dose metric that incorporates light dosimetry, sensitizer dosimetry, and triplet quenching efficiency is introduced. All components of this metric can be determined by optical measurements.

Weston, Mark A.; Patterson, Michael S.

2013-10-01

170

Photodynamic therapy repeated without reinjection of Photofrin (porfimer sodium)  

NASA Astrophysics Data System (ADS)

Background and objective: To compare the effectiveness in decreasing the amount of obstruction caused by endobronchial tumors when they are retreated with photodynamic therapy (PDT) several weeks after injection of PhotofrinR (porfimer sodium). Study design, materials and methods: The percentage of endobronchial obstruction from tumors before PDT and at the end of toilet bronchoscopy of 91 sites with PDT performed within 4 days after injection of porfimer sodium was compared to that obtained when PDT was repeated without re-injection of porfimer sodium in the time frames 2 - 4 weeks after injection to 11 sites and the period 4 - 8 weeks after injection to 17 sites. All patients were injected intravenously with 60 mg of PhotofrinR per square meter of body surface and all treatments were done with a power density of 500 mW/CF and a light dose of 400 J/CF delivered from cylinder diffusing fibers. Results: Paired Student's t tests and Wilcoxon signed ranks tests showed significant decreases in the percentage of endobronchial obstruction regardless of whether the PDT was first performed or repeated. Unpaired Student's t tests and Mann-Whitney U statistical comparisons showed a significant difference between the decrease of obstruction when treatment was performed within the first 4 days after injection (mean 41%) as compared to the repeated group 2 to 4 weeks after injection (mean 16%) and the group treated 4 to 8 weeks after injection (mean 19%). However there was no significant difference in the amount of decrease of obstruction between the 2 - 4 week group and the 4 - 8 week group. Conclusions: Photodynamic therapy to relieve endobronchial obstruction can be repeated without reinjection of PhotofrinR up to 8 weeks after injection with a significant decrease in the amount of obstruction. However, it will only be about 1/3 as effective as the initial treatment performed within the first four days of injection.

McCaughan, James S.

1998-05-01

171

Antimicrobial photodynamic therapy to kill Gram-negative bacteria.  

PubMed

Antimicrobial photodynamic therapy (PDT) or photodynamic inactivation (PDI) is a new promising strategy to eradicate pathogenic microorganisms such as Gram-positive and Gram-negative bacteria, yeasts and fungi. The search for new approaches that can kill bacteria but do not induce the appearance of undesired drug-resistant strains suggests that PDT may have advantages over traditional antibiotic therapy. PDT is a non-thermal photochemical reaction that involves the simultaneous presence of visible light, oxygen and a dye or photosensitizer (PS). Several PS have been studied for their ability to bind to bacteria and efficiently generate reactive oxygen species (ROS) upon photo-stimulation. ROS are formed through type I or II mechanisms and may inactivate several classes of microbial cells including Gram-negative bacteria such as Pseudomonas aeruginosa, which are typically characterized by an impermeable outer cell membrane that contains endotoxins and blocks antibiotics, dyes, and detergents, protecting the sensitive inner membrane and cell wall. This review covers significant peer-reviewed articles together with US and World patents that were filed within the past few years and that relate to the eradication of Gram-negative bacteria via PDI or PDT. It is organized mainly according to the nature of the PS involved and includes natural or synthetic food dyes; cationic dyes such as methylene blue and toluidine blue; tetrapyrrole derivatives such as phthalocyanines, chlorins, porphyrins, chlorophyll and bacteriochlorophyll derivatives; functionalized fullerenes; nanoparticles combined with different PS; other formulations designed to target PS to bacteria; photoactive materials and surfaces; conjugates between PS and polycationic polymers or antibodies; and permeabilizing agents such as EDTA, PMNP and CaCl?. The present review also covers the different laboratory animal models normally used to treat Gram-negative bacterial infections with antimicrobial PDT. PMID:23550545

Sperandio, Felipe F; Huang, Ying-Ying; Hamblin, Michael R

2013-08-01

172

Photodynamic Therapy for Head and Neck Dysplasia and Cancer  

PubMed Central

Objective To determine the response of dysplasia, carcinoma in situ (CIS), and T1 carcinoma of the oral cavity and larynx to photodynamic therapy with porfimer sodium. Design Prospective trial. Setting A National Cancer Institute–designated cancer institute. Patients Patients with primary or recurrent moderate to severe oral or laryngeal dysplasia, CIS, or T1N0 carcinoma. Intervention Porfimer sodium, 2 mg/kg of body weight, was injected intravenously 48 hours before treatment. Light at 630 nm for photosensitizer activation was delivered from an argon laser or diode laser using lens or cylindrical diffuser fibers. The light dose was 50 J/cm2 for dysplasia and CIS and 75 J/cm2 for carcinoma. Main Outcome Measures Response was evaluated at 1 week and at 1 month and then at 3-month intervals thereafter. Response options were complete (CR), partial (PR), and no (NR) response. Posttreatment biopsies were performed in all patients with persistent and recurrent visible lesions. Results Thirty patients were enrolled, and 26 were evaluable. Mean follow-up was 15 months (range, 7–52 months). Twenty-four patients had a CR, 1 had a PR, and 1 had NR. Three patients with oral dysplasia with an initial CR experienced recurrence in the treatment field. All the patients with NR, a PR, or recurrence after an initial CR underwent salvage treatment. Temporary morbidities included edema, pain, hoarseness, and skin phototoxicity. Conclusion Photodynamic therapy with porfimer sodium is an effective treatment alternative, with no permanent sequelae, for oral and laryngeal dysplasia and early carcinoma.

Rigual, Nestor R.; Thankappan, Krishnakumar; Cooper, Michele; Sullivan, Maureen A.; Dougherty, Thomas; Popat, Saurin R.; Loree, Thom R.; Biel, Merrill A.; Henderson, Barbara

2009-01-01

173

Decontamination of dental implant surfaces by means of photodynamic therapy.  

PubMed

Several implant surface debridement methods have been reported for the treatment of peri-implantitis, however, some of them can damage the implant surface or promote bacterial resistance. Photodynamic therapy (PDT) is a new treatment option for peri-implantitis. The aim of this in vitro study was to analyze implant surface decontamination by means of PDT. Sixty implants were equally distributed (n = 10) into four groups and two subgroups. In group G1 there was no decontamination, while in G2 decontamination was performed with chlorhexidine. G3 (PDT - laser + dye) and G4 (laser, without dye) were divided into two subgroups each; with PDT performed for 3 min in G3a and G4a, and for 5 min in G3b and G4b. After 5 min in contact with methylene blue dye (G3), the implants were irradiated (G3 and G4) with a low-level laser (GaAlAs, 660 nm, 30 mW) for 3 or 5 min (7.2 and 12 J). After the dilutions, culture media were kept in an anaerobic atmosphere for 1 week, and then colony forming units were counted. There was a significant difference (p < 0.001) between G1 and the other groups, and between G4 in comparison with G2 and G3. Better decontamination was obtained in G2 and G3, with no statistically significant difference between them. The results of this study suggest that photodynamic therapy can be considered an efficient method for reducing bacteria on implant surfaces, whereas laser irradiation without dye was less efficient than PDT. PMID:22790655

Marotti, Juliana; Tortamano, Pedro; Cai, Silvana; Ribeiro, Martha Simões; Franco, João Eduardo Miranda; de Campos, Tomie Toyota

2012-07-12

174

Photodynamic Therapy in Unresectable Cholangiocarcinoma: Not for the Uncommitted  

PubMed Central

Background/Aims Photodynamic therapy (PDT) in unresectable cholangiocarcinoma has been associated with improved survival. We report a single tertiary care center experience over the past 6 years. Methods Fifty-five patients with unresectable cholangiocarcinoma received PDT between 2004 and 2010. Plastic stents were placed after PDT to prevent cholangitis. Results Twenty-seven patients (49%) showed Bismuth type IV, 22 (41%) showed Bismuth type III, and six (10%) showed Bismuth type I and II. Twenty patients (37%) received chemotherapy and radiation therapy, five (9%) received chemotherapy only; and one (2%) received radiation therapy only. Mean number of PDT sessions was 1.9±1.5 sessions (range, 1 to 9). Mean survival duration was 293±266 days (median, 190; range, 25 to 1,332). PDT related complications included three (5%) facial burn, three (5%) photosensitivity, and two (3%) rash. Kaplan-Meier analysis comparing the survival means of patients who received PDT and chemotherapy/radiation therapy (median survival 257 days; 95% confidence interval [CI], 166 to 528) versus who received PDT only (median survival 183 days; 95% CI, 129 to 224) showed no significant difference (log-rank p=0.20). Conclusions PDT has a measurable impact on survival in unresectable cholangiocarcinoma but requires aggressive stenting posttherapy.

Talreja, Jayant P.; DeGaetani, Marisa; Ellen, Kristi; Schmitt, Timothy; Gaidhane, Monica

2013-01-01

175

Synergistic Anti-Tumor Effects of Combination of Photodynamic Therapy and Arsenic Compound in Cervical Cancer Cells: In Vivo and In Vitro Studies  

PubMed Central

The effects of As4O6 as adjuvant on photodynamic therapy (PDT) were studied. As4O6 is considered to have anticancer activity via several biological actions, such as free radical production and inhibition of VEGF expression. PDT or As4O6 significantly inhibited TC-1 cell proliferation in a dose-dependent manner (P<0.05) by MTT assay. The anti-proliferative effect of the combination treatment was significantly higher than in TC-1 cells treated with either photodynamic therapy or As4O6 alone (62.4 and 52.5% decrease compared to vehicle-only treated TC-1 cells, respectively, P<0.05). In addition, cell proliferation in combination of photodynamic therapy and As4O6 treatment significantly decreased by 77.4% (P<0.05). Cell survival pathway (Naip1, Tert and Aip1) and p53-dependent pathway (Bax, p21Cip1, Fas, Gadd45, IGFBP-3 and Mdm-2) were markedly increased by combination treatment of photodynamic therapy and As4O6. In addition, the immune response in the NEAT pathway (Ly-12, CD178 and IL-2) was also modulated after combination treatment, suggesting improved antitumor effects by controlling unwanted growth-stimulatory pathways. The combination effect apparently reflected concordance with in vitro data, in restricting tumor growth in vivo and in relation to some common signaling pathways to those observed in vitro. These findings suggest the benefit of combinatory treatment with photodynamic therapy and As4O6 for inhibition of cervical cancer cell growth.

Kim, Yong-Wan; Bae, Su Mi; Battogtokh, Gantumur; Bang, Hyo Joo; Ahn, Woong Shick

2012-01-01

176

Photodynamic therapy using mono-L-aspartyl chlorin e6 for rabbit experimental hepatoma.  

PubMed

Photodynamic therapy and photodynamic diagnosis using photosensitizers have yet to be clinically employed for hepatoma. Mono-L-aspartyl chlorin e6, a chlorin derivative with high tumor affinity developed as a second-generation photosensitizer, enables rapid tumor detection after administration, without light-shielding. This study examined the potential of photodynamic therapy, using this photosensitizer, for hepatoma in rabbits. VX2 tumor cells were transplanted into the liver of Japanese white rabbits, and the animals were administered 2.5 mg/kg of mono-L-aspartyl chlorin 36 1 week later. Accumulation of mono-L-aspartyl chlorin e6 in hepatoma was observed over time with an epifluorescence stereoscope, and the efficacy of continuous photodynamic therapy following photodynamic diagnosis was examined. A diode laser system was used for treatment, and efficacy was examined in a control group and four other groups that were irradiated at different times following administration. Efficacy in suppressing tumor growth, tumor necrosis rates, and efficacy in suppressing pulmonary metastasis were studied. For all these aspects, treatment was significantly more effective in the group irradiated 5 minutes after administration than in groups irradiated at later times. Liver function testing in all groups revealed no distinct disorders. Photodynamic therapy with mono-L-aspartyl chlorin e6 may be suitable for clinical use in therapy for hepatoma. PMID:10526068

Nakamura, J; Kajiwara, H

1999-01-01

177

Advance in photosensitizers and light delivery for photodynamic therapy.  

PubMed

The brief history of photodynamic therapy (PDT) research has been focused on photosensitizers (PSs) and light delivery was introduced recently. The appropriate PSs were developed from the first generation PS Photofrin (QLT) to the second (chlorins or bacteriochlorins derivatives) and third (conjugated PSs on carrier) generations PSs to overcome undesired disadvantages, and to increase selective tumor accumulation and excellent targeting. For the synthesis of new chlorin PSs chlorophyll a is isolated from natural plants or algae, and converted to methyl pheophorbide a (MPa) as an important starting material for further synthesis. MPa has various active functional groups easily modified for the preparation of different kinds of PSs, such as methyl pyropheophorbide a, purpurin-18, purpurinimide, and chlorin e6 derivatives. Combination therapy, such as chemotherapy and photothermal therapy with PDT, is shortly described here. Advanced light delivery system is shown to establish successful clinical applications of PDT. Phtodynamic efficiency of the PSs with light delivery was investigated in vitro and/or in vivo. PMID:23423543

Yoon, Il; Li, Jia Zhu; Shim, Young Key

2013-01-31

178

Comparative photodynamic therapy study using two phthalocyanine derivatives  

PubMed Central

In the present study, a comparative photodynamic therapy (PDT) study was performed using the phthalocyanine derivatives, ZnPc(OCH3)4 and ZnPc(CF3)4, in a mouse tumor model, under identical experimental procedures. We studied the ablation of tumors induced by PDT. The end-point was to compare the photodynamic efficacy of ZnPc(OCH3)4 and ZnPc(CF3)4. ZnPc(OCH3)4 and ZnPc(CF3)4 were administered intraperitoneally at a dose of 0.2 mg/kg body weight. The injections of drugs were carried out in Balb/c mice bearing subcutaneously inoculated LM2 mouse mammary adenocarcinoma. Histological examination and serum biochemical parameters were used to evaluate hepatic and renal toxicity and function. Phototherapeutic studies were achieved employing a light intensity of 210 J/cm2. After PDT, tumoral regression analyses were carried out, and the degree of tumor cell death was measured utilizing the vital stain Evan’s blue. In this pilot study, we revealed that the cytotoxic effect of ZnPc(OCH3)4 after PDT led to a higher success rate compared to ZnPc(CF3)4-PDT when both were intraperitoneally injectioned. Both phthalocynanine derivatives were able to induce ablation in the tumors. In summary, these results demonstrate the feasibility of ZnPc(OCH3)4- or ZnPc(CF3)4-PDT and its potential as a treatment for small tumors.

YSLAS, EDITH INES; MILLA, LAURA NATALIA; ROMANINI, SILVIA; DURANTINI, EDGARDO NESTOR; BERTUZZI, MABEL; RIVAROLA, VIVIANA ALICIA

2010-01-01

179

Combination of photodynamic therapy and immunotherapy - evolving role in dermatology  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is a promising treatment modality. It offers alternative options in the treatment of cancer and vascular diseases. In cancer treatment, PDT has been used primarily for localized superficial or endoluminal malignant and premalignant conditions. More recently, its application has also been expanded to solid tumors. However, its antitumor efficacy remains debatable and its acceptance still variable. Pre-clinical studies demonstrate that, in addition to the primary local cytotoxicity, PDT might induce secondary host immune responses, which may further enhance PDT's therapeutic effects on primary tumor as well as metastasis. Therefore, PDT-induced local and systemic antitumor immune response might play an important role in successful control of malignant diseases. Furthermore, PDT's antitumor efficacy might also be enhanced through an effective immunoadjuvant or immunomodulator. Our recent clinical data also indicate that improved clinical outcomes can be obtained by a combination of PDT and immunomodulation therapy for the treatment of pre-malignant skin diseases. For instance, the combination of topical ALA-PDT and Imiquimod is effective for the treatment of genital bowenoid papulosis. This presentation will also report our preliminary data in developing combination approaches of PDT and immunotherapy for actinic keratosis (AK), basal cell carcinomas (BCCs) and Bowen's disease.

Wang, Xiu-Li; Wang, Hong-Wei; Huang, Zheng

2008-03-01

180

Photodynamic therapy in early esophageal squamous cell carcinoma  

NASA Astrophysics Data System (ADS)

From 1/1985 to 7/1993, 18 patients underwent endoscopic photodynamic therapy (PDT) for early stage esophageal squamous cell carcinoma -- as two patients had two synchronous esophageal cancers, 20 lesions were treated. Tumors were staged as Tis in 7 cases and T1 in 13. The average light energy delivered was 50 J/cm2 and 70 J/cm2 for the treatment of Tis and T1, respectively. To obtain a more uniform distribution of laser light in 12 cases the irradiation was performed through the wall of a transparent tube previously placed over the endoscope and advanced into the stomach. The overall results show a complete response in 14/20 (70%) tumors. Three patients developed a local recurrence, 6, 12, and 14 months after therapy. After a follow-up of 5 to 75 months, there was no evidence of disease in 10/18 patients (56%). The actuarial survival rate was 95%, 79%, and 26% at 1, 3, and 5 years, respectively. Complications were skin reaction in one patient and esophageal stenosis at the treatment site, that gradually responded to endoscopic bougienage, in 2 patients. Endoscopic PDT proved to be safe and effective in the treatment of superficial carcinoma of the esophagus.

Spinelli, Pasquale; Dal Fante, Marco; Mancini, Andrea; Massetti, Renato; Meroni, Emmanuele

1994-10-01

181

Photodynamic therapy in early esophageal squamous cell carcinoma  

NASA Astrophysics Data System (ADS)

From 1/1985 to 7/1993, 18 patients underwent endoscopic photodynamic therapy (PDT) for early stage esophageal squamous cell carcinoma -- as two patients had two synchronous esophageal cancers, 20 lesions were treated. Tumors were staged as Tis in 7 cases and T1 in 13. The average light energy delivered was 50 J/cm2 and 70 J/cm2 for the treatment of Tis and T1, respectively. To obtain a more uniform distribution of laser light in 12 cases the irradiation was performed through the wall of a transparent tube previously placed over the endoscope and advanced into the stomach. The overall results show a complete response in 14/20 (70%) tumors. Three patients developed a local recurrence, 6, 12, and 14 months after therapy. After a follow-up of 5 to 75 months, there was no evidence of disease in 10/18 patients (56%). The actuarial survival rate was 95%, 79%, and 26% at 1, 3, and 5 years, respectively. Complications were skin reaction in one patient and esophageal stenosis at the treatment site, that gradually responded to endoscopic bougienage, in 2 patients. Endoscopic PDT proved to be safe and effective in the treatment of superficial carcinoma of the esophagus.

Spinelli, Pasquale; dal Fante, Marco; Mancini, Andrea; Massetti, Renato; Meroni, Emmanuele

1995-03-01

182

Innovative approaches of clinical photodynamic therapy combined with immunotherapy  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is a clinically approved new treatment modality. It has been used for treatment of non-malignant and malignant diseases. Over the last decade its clinical application has gained increasing acceptance around the world after regulatory approvals. PDT offers various treatment options in cancer management and has been used primarily for localized superficial or endoluminal malignant and premalignant conditions. Recently, its application has also been expanded to solid tumors. However, its efficacy for the treatment of malignant tumors remains debatable and its acceptance still variable. Pre-clinical studies demonstrate that, in addition to the direct local cytotoxicity, PDT can induce host immune responses, which may further enhance the therapeutic effects on primary tumor as well as metastasis. Therefore, PDT-induced antitumor immune response might play an important role in successful control of malignant diseases. Furthermore, the antitumor efficacy of PDT might also be enhanced through an effective immunoadjuvant to further expand its usefulness for a possible control of distant metastases. Recent clinical data also indicate that improved clinical outcomes are seen in the combination of PDT and immunomodulation therapy for non-malignant disease. This review will summarize recent progress in developing innovative approaches of PDT combined with immunotherapy for non-malignant and malignant diseases.

Huang, Zheng

2006-03-01

183

Cell Death Pathways in Photodynamic Therapy of Cancer  

PubMed Central

Photodynamic therapy (PDT) is an emerging cancer therapy that uses the combination of non-toxic dyes or photosensitizers (PS) and harmless visible light to produce reactive oxygen species and destroy tumors. The PS can be localized in various organelles such as mitochondria, lysosomes, endoplasmic reticulum, Golgi apparatus and plasma membranes and this sub-cellular location governs much of the signaling that occurs after PDT. There is an acute stress response that leads to changes in calcium and lipid metabolism and causes the production of cytokines and stress response mediators. Enzymes (particularly protein kinases) are activated and transcription factors are expressed. Many of the cellular responses center on mitochondria and frequently lead to induction of apoptosis by the mitochondrial pathway involving caspase activation and release of cytochrome c. Certain specific proteins (such as Bcl-2) are damaged by PDT-induced oxidation thereby increasing apoptosis, and a build-up of oxidized proteins leads to an ER-stress response that may be increased by proteasome inhibition. Autophagy plays a role in either inhibiting or enhancing cell death after PDT.

Mroz, Pawel; Yaroslavsky, Anastasia; Kharkwal, Gitika B; Hamblin, Michael R.

2011-01-01

184

Metallobacteriochlorophylls as potential dual agents for photodynamic therapy and chemotherapy.  

PubMed

A theoretical analysis of bacteriochlorophyll a containing its non-native divalent metal ions: Co, Ni, Cu, Zn, Ru, Rh, Pd, and Pt, has been carried out by means of density functional theory (DFT) calculations. The main stress was put on the derivatives with metals, which already found applications as coordination compounds in anti-tumor therapy (Ru, Pt, Pd, and Rh). The idea was to combine their cytotoxic properties with the known suitability of bacteriochlorophylls macrocycle for photodynamic therapy. The geometries of the studied systems are compared and reveal a number of similarities. The cores of the modified bacteriochlorophylls are flat, and the introduced metal ions lie in plane of the macrocycle, showing its large ability to accommodate metal ions of different sizes. However, four metal-nitrogen bonds, linking the central ions with the macrocycle ligand, are not equivalent. Metals are the strongest attached to nitrogens, which come from the pyrrole, which is fused with isocyclic ring. Based on the known spectroscopic data, the absorption properties of the proposed systems are predicted. Finally, it is found that all studied metal-macrocycle adducts are stable in aqueous media. The only exceptions are Mg-BChla (the finding is reflected by experimental facts) and Zn-BChla. The predicted high stability of Ru-, Rh-, Pt- and Pd-bacteriochlorophylls might turn out beneficial for therapeutic purposes. PMID:23306811

Rutkowska-Zbik, Dorota; Witko, Ma?gorzata

2013-01-12

185

Photodynamic therapy for the prevention of restenosis after angioplasty  

NASA Astrophysics Data System (ADS)

The purpose of this study was to evaluate whether photodynamic therapy (PDT) can destroy the proliferating smooth muscle cells and therefore suppress the occurrence of restenosis after angioplasty. PDT following administration of hematoporphyrin derivatives (HpD) 24 hours before irradiation was performed on 30 rabbits immediately (0D), 3 days (3D), 1 week (1W) and 2 weeks (2W) after balloon injury. HpD accumulation of each group was investigated simultaneously. Irradiation of 27 J/10 mm2 from an Hg-Xe flash lamp light transmitted through an 800 micrometers quartz fiber with a diffusing tip was used. All rabbits were sacrificed 4 weeks after balloon injury. The results were expressed in terms of intima:media thickness ratio at the site of fiber contact (I/M) and intima:media area ratio of the cross section (IA/MA). Inhibition of intimal thickening evaluated on the basis of the I/M ratio was recognized in the 3D-, 1W-, and 2W-PDT group. The most effective photoradiation was at the 1W-PDT (I/M equals 0.78 +/- 0.67), but in 2W-PDT intimal necrosis resulting in a small amount of thickness was observed with less media necrosis. ThreeD and 0D PDT effects reduced with media necrosis. We conclude that PDT after angioplasty would be an ideal preventional therapy of restenosis.

Asahara, Takayuki; Usui, Mikio; Amemiya, Takashi; Oike, Yasuhisa; Shiraishi, Hiromori; Miyagi, Manabu; Nakajima, Hitoshi; Kato, Tomitsugu; Naito, Yuichi; Ibukiyama, Chiharu

1993-06-01

186

Adjuvant therapy for ampullary carcinomas: The Mayo Clinic experience  

SciTech Connect

Purpose: To determine the effects of adjuvant radiotherapy and chemotherapy for carcinoma of the ampulla of Vater. Methods and Materials: We retrospectively reviewed the records of 125 patients who underwent definitive surgery for carcinomas involving the ampulla of Vater between April 1977 and February 2005 and who survived more than 50 days after surgery. Twenty-nine of the patients also received adjuvant radiotherapy (median dose, 50.4 Gy in 28 fractions) with concurrent 5-fluorouracil chemotherapy. Adverse prognostic factors were investigated, and overall survival (OS) and local and distant failure were estimated. Results: Adverse prognostic factors for decreased OS by univariate analysis included lymph node (LN) involvement, locally advanced tumors (T3/T4), and poor histologic grade. By multivariate analysis, positive LN status (p = 0.02) alone was associated with decreased OS. The addition of adjuvant radiotherapy and chemotherapy improved OS for patients with positive LN (p = 0.01). Median survival for positive LN patients receiving adjuvant therapy was 3.4 years, vs. 1.6 years for those with surgery alone. Conclusions: The addition of adjuvant radiotherapy and 5-fluorouracil chemotherapy may improve OS in patients with LN involvement. The effect of adjuvant therapy on outcomes for patients with poor histologic grade or T3/T4 tumors without LN involvement could not be assessed.

Bhatia, Sumita [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Miller, Robert C. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States)]. E-mail: miller.robert@mayo.edu; Haddock, Michael G. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Donohue, John H. [Division of Gastroenterologic and General Surgery, Mayo Clinic, Rochester, MN (United States); Krishnan, Sunil [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States)

2006-10-01

187

Controversies in the Adjuvant Therapy of Endometrial Cancer  

PubMed Central

Endometrial cancer is the most common malignancy of the female genital tract. Surgical treatment includes hysterectomy, bilateral salpingo-oophorectomy, and an appropriate staging procedure. Relapse of endometrial cancer may occur in patients with high risk factors, such as old age, grade 3 cancer, deep myometrial invasion, and papillary serous and clear cell types. In recent years, several randomized trials reported the results of adjuvant therapy for patients with high risk factors. Nonetheless, some controversies still exist. This paper presents and discusses the results of important randomized trials of adjuvant therapy for endometrial cancer with risk factors.

Hsiao, Sheng-Mou; Wei, Lin-Hung

2011-01-01

188

Photodynamic therapy of non-melanoma skin cancers  

NASA Astrophysics Data System (ADS)

In this prospective study duly approved from Institutional Ethics Review Committee for research in medicine, PAEC General Hospital Islamabad, Pakistan, we investigate the efficacy, safety and tolerability along with cosmetic outcome of topical 5-aminolaevulinic acid photodynamic therapy for superficial nonmelanoma skin cancers (NMSCs) and their precursors. Patients with Histological diagnosis of NMSCs and their precursors were assessed for PDT, after photographic documentation of the lesions and written consent, underwent two (2) sessions of PDT in one month (4 weeks) according to standard protocol. A freshly prepared 20% 5-ALA in Unguentum base was applied under occlusive dressing for 4-6 h as Drug Light Interval (DLI) and irradiated with light of 630 nm wavelength from a diode laser at standard dose of 90 J/cm2. Approximately 11% patients reported pain during treatment which was managed in different simple ways. In our study we regularly followed up the patients for gross as well as histopathological response and recurrence free periods during median follow-up of 24 months. Regarding Basal cell carcinomas complete response was observed in 86.2% (25/29), partial response in 10.3% (3/29) and recurrence during first year in 3.5% (1/29) lesions. All the lesions which showed partial response or recurrence were nBCCs. Regarding Actinic Keratosis complete response was observed in 95.3% (20/21), partial response in 4.7% (1/21) while Bowen's disease showed 100% (2/2) results. 81.8% (9/11) Squamous Cell Carcinomas showed complete, 9% (1/11) partial response and 9% (1/11) presented with recurrence after 3 months. We observed excellent and good cosmetic results along with tumor clearance in our study. Treatment sessions were well tolerated with high level of patient's satisfaction and only minor side effects of pain during treatment sessions and inflammatory changes post photodynamic therapy were observed. We concluded that 5-ALA PDT is an effective and safe emerging treatment modality for management of superficial non-melanoma skin cancers and their precursors with better cosmetic outcome and minor side effects.

Ikram, M.; Khan, R. U.; Firdous, S.; Atif, M.; Nawaz, M.

2011-02-01

189

Anti-CTLA-4 antibody adjuvant therapy in melanoma.  

PubMed

Thus far the development of adjuvant therapies in melanoma has suffered greatly from the lack of effective drugs in stage IV melanoma. Chemotherapy, cytokines, vaccines, and combinations of drugs have been used with minimal success. This has led to adjuvant therapies that are not used uniformly or widely because of the rather marginal benefits, as no consistent and clinically significant impact on survival has been demonstrated. A new development for interferon-based adjuvant therapy seems to be the observation that better effects are observed in patients with lower tumor load and in patients with an ulcerated primary melanoma. A benefit for patients with more advanced lymphnodal involvement is quite unsure, clearly requiring new drugs to be explored. A new era in the treatment of melanoma treatment has arrived with the anti-cytoxic T-lymphocyte antigen-4 (anti-CTLA-4) monoclonal antibodies. The randomized trial in advanced metastatic melanoma demonstrated a clear benefit with prolongation of survival. The anti-CTLA-4 monoclonal antibody ipilimumab has finally changed the landscape. It is therefore only logical that a worldwide adjuvant trial with ipilimumab versus placebo, the European Organization for Research and Treatment of Cancer (EORTC) 18071, is ongoing in patients with lymph node metastases, and that another adjuvant trial with ipilimumab compared to high-dose interferon (HDI) is planned in the United States. The EORTC 18071 trial will reach full accrual in 2011 and thus results are expected in 2013 or 2014. PMID:21074060

Eggermont, Alexander M M; Testori, Alessandro; Maio, Michele; Robert, Caroline

2010-10-01

190

Mechanisms of tumor destruction caused by photodynamic therapy  

NASA Astrophysics Data System (ADS)

Photodynamic therapy is a relatively new treatment modality and is becoming widely accepted as a standard treatment of a variety of solid tumors. This includes palliative treatments for advanced or obstructive cancers in many organs as well as a curative treatment for some early cancers and pre-cancerous lesions. It has been approved by health authorities in a number of countries in America, Europe and Asia [1]. PDT is a procedure requiring 3 elements: photosensitizer, light and oxygen [2]. The typical technique involves an intravenous administration of a photosensitizing agent, which is preferentially accumulated or retained in tumor tissue, followed by irradiation of the tumor area with light of appropriate wavelength. In the presence of oxygen it generates highly reactive and cytotoxic molecular species, in particular, singlet oxygen (1O2), which may oxidize various bio-molecules and finally leading to cell death and tumor destruction [3]. The most widely used photosensitizer in clinical treatment of cancers is Photofrin (porfimer sodium), and most widely used light sources are lasers of various types, in recent years preferentially, diode laser, which emits a red light of 630 nm wavelength.

Zhou, Chuannong

2005-07-01

191

Tumor Vascular Microenvironment Determines Responsiveness to Photodynamic Therapy  

PubMed Central

The efficacy of photodynamic therapy (PDT) depends upon the delivery of both photosensitizing drug and oxygen. In this study, we hypothesized that local vascular microenvironment is a determinant of tumor response to PDT. Tumor vascularization and its basement membrane (collagen) were studied as a function of supplementation with basement membrane matrix (Matrigel) at the time of tumor cell inoculation. Effects on vascular composition with consequences to tumor hypoxia, photosensitizer uptake and PDT response were measured. Matrigel-supplemented tumors developed more normalized vasculature, composed of smaller and more uniformly-spaced blood vessels than their unsupplemented counterparts, but these changes did not affect tumor oxygenation or PDT-mediated direct cytotoxicity. However, PDT-induced vascular damage increased in Matrigel-supplemented tumors, following an affinity of the photosensitizer Photofrin for collagen-containing vascular basement membrane coupled with increased collagen content in these tumors. The more highly-collagenated tumors demonstrated more vascular congestion and ischemia after PDT, along with a higher probability of curative outcome that was collagen dependent. In the presence of photosensitizer-collagen localization, PDT effects on collagen were evidenced by a decrease in its association with vessels. Together, our findings demonstrate that photosensitizer localization to collagen increases vascular damage and improves treatment efficacy in tumors with greater collagen content. The vascular basement membrane is thus identified to be a determinant of therapeutic outcome in PDT of tumors.

Maas, Amanda L.; Carter, Shirron L.; Wileyto, E. Paul; Miller, Joann; Yuan, Min; Yu, Guoqiang; Durham, Amy C.; Busch, Theresa M.

2012-01-01

192

Effects of vascular targeting photodynamic therapy on lymphatic tumor metastasis  

NASA Astrophysics Data System (ADS)

Vascular targeting photodynamic therapy (vPDT) is currently in clinical trial for prostate cancer (PCa) treatment. In order to study the effect of vPDT on tumor metastasis, GFP-PC3 or PC-3 xenografts were treated with verteporfin (BPD) PDT. Vascular function was assessed by ultrasound imaging; lymph node and lung metastasis were assessed by fluorescence imaging. vPDT significantly reduced tumor blood flow within 30minutes to 2 hours of treatment. Sub-curative treatment resulted in re-perfusion within 2 weeks of treatment and increased lymph node metastasis. With curative doses, no metastasis was observed. In order to identify cellular or matrix factors and cytokines implicated, conditioned medium from BPD PDTtreated endothelial cells was incubated with PC3 cells in vitro. Tumor cell proliferation and migration was assessed. By immunoblotting, we evaluated the change in mediators of intracellular signaling or that may determine changes in tumor phenotype. Low sub-curative dose (200ng/ml BPD) of endothelial cells was associated with ~15% greater migration in PC3 cells when compared with control. This dose was also associated with sustained activation of Akt at Ser 473, an upstream effector in the Akt/ mTOR pathway that has been correlated with Gleason scores in PCa and with survival and metastasis in vitro and in vivo. In conclusion, the study implicates efficacy of PDT of endothelial cells as an important determinant of its consequences on adjacent tumor proliferation and metastasis.

Fateye, B.; He, C.; Chen, B.

2009-06-01

193

Characterizing light propagation in bone for photodynamic therapy of osteosarcoma  

NASA Astrophysics Data System (ADS)

This work aims at characterizing how light propagates through bone in order to efficiently guide treatment of osteosarcoma with photodynamic therapy (PDT). Optical properties of various bone tissues need to be characterized in order to have a working model of light propagation in bone. Bone tissues of particular interest include cortical bone, red and yellow marrow, cancellous bone, and bone cancers themselves. With adequate knowledge of optical properties of osseous tissues, light dosimetry can determine how best to deliver adequate light to achieve phototoxic effects within bone. An optical fiber source-collector pair is used for diffuse reflectance spectroscopic measurements in order to determine the scattering and absorption properties of bone tissues. Native absorbers of interest at visible and near-IR wavelengths include water and oxygenated and deoxygenated hemoglobin. A cylindrically symmetric Monte Carlo model is then used, incorporating these results, in order to predict and guide the delivery of light within bone in order to achieve the desired phototoxic effect in PDT.

Rossi, Vincent M.; Gustafson, Scott B.; Jacques, Steven L.

2009-02-01

194

Photodynamic therapy in AIDS-related cutaneous Kaposi's sarcoma.  

PubMed

For evaluating the role of photodynamic therapy (PDT) in the local treatment of acquired immune deficiency syndrome (AIDS)-related cutaneous Kaposi's sarcoma (KS), nine treatments were performed in eight human immunodeficiency virus-positive homosexual men. The patients received 2 mg Photofrin/kg and either 120 J/cm2 (n = 5) or 70 J/cm2 (n = 4) laser light (630 nm). A total of 83 lesions were evaluable for response with a follow-up of 3-8 months. The overall response rates by patient for all treated lesions were 50-100% (120 J/cm2) and 83.3-90.3% (70 J/cm2), with a median duration of 3 months (range, 2-6 months). Tumors located at the head had higher response rates than those at the trunk or extremities (p = 0.005 and p - 0.015 respectively). The size of the KS showed a negative relationship with the probability of complete response (p = 0.047). Local and general side effects occurred, including pain, blisters, temperature increase, muscle stiffness, and severe edema. The cosmetic result was unsatisfactory because of a high prevalence of scars and long-lasting hyperpigmentation. Although the response rates of PDT are high, light dose of 70-120 J/cm2 cannot be recommended in the treatment of cutaneous KS in combination with 2 mg/kg Photofrin because of severe side effects and unsatisfactory cosmetic result. PMID:7648286

Hebeda, K M; Huizing, M T; Brouwer, P A; van der Meulen, F W; Hulsebosch, H J; Reiss, P; Oosting, J; Veenhof, C H; Bakker, P J

1995-09-01

195

[Temperature regime of biological tissue under photodynamic therapy].  

PubMed

An analytical model is proposed to calculate heating of human skin cover under laser light action of photodynamic therapy. A photosensitizer of "Fotolon" is taken as an example. Temperatures of skin surface and of deep dermis regions are studied as a function of time under pulsed and stationary irradiation of skin surface at the wavelength of 665 nm corresponding to the maximum of the photosensitizer absorption band. It is shown that, under the action of a short light pulse, the photosensitizer can lead to an essential temperature rise of dermis due to a considerable increase in its absorption coefficient. However, this rise does not destruct tissue cells because of the short action. Under stationary irradiation, the photosensitizer concentration has a low effect on the temperature regime of tissue. This is related with the specific features in heating of the medium by red light, where the main thermal process in skin is heat transfer over tissue volume from epidermis having a substantially larger absorption coefficient than that of dermis in the said spectral range. The role of blood perfusion in dermis and its effect on the temperature regime of tissue are evaluated. PMID:22567919

Barun, V V; Ivanov, A P

196

Optimization of photodynamic therapy with chlorins for chest malignancies  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) following surgical tumor resection is leading to improved local tumor control and might be useful for selected intrathoracic malignancies. However, optimal tumor selectivity of PDT is mandatory to avoid injury of adjacent normal tissues. (1) PDT was applied on human tumor xenografts (malignant mesothelioma, squamous cell carcinoma of the neck, adenocarcinoma of the colon). M-tetrahydroxyphenylchlorin (mTHPC) and polyethylene glycol-derived mTHPC (MD-mTHPC) were administered i.p. The tumor and normal tissue of the hind leg were irradiated with 652 nm laser-light. Drug and light doses and drug-light intervals were varied. The extent of necrosis was assessed histologically. (2) Intrathoracic PDT was performed in minipigs with drug-light doses optimized in nude mice. After administration of the sensitizers i.v., intrathoracic structures were irradiated and analyzed histologically. The tumor selectivity of PDT increased in the xenograft model by: (1) choosing an appropriate drug light interval; (2) decreasing the drug dose while increasing the light dose; and (3) applying MD-mTHPC instead of mTHPC. In the minipig model, the extent of injury of intrathoracic structures was equally related to modulation of treatment conditions. The modification of chlorins and the modulation of the drug-light conditions improved the tissue selectivity of PDT. Nevertheless, further methodological optimizations are prerequisites for clinical use of PDT, especially for intraoperative application in thoracic surgery.

Ris, Hans-Beat; Giger, Andreas; Im Hof, Vinzenz; Althaus, Ulrich; Altermatt, Hans J.

1996-01-01

197

Light distribution in the endometrium during photodynamic therapy  

NASA Astrophysics Data System (ADS)

Hysterectomy is the most common major operation performed in the United States with dysfunctional uterine bleeding being a major indication. Endometrial destruction by photodynamic therapy (PDT) has been suggested as a possible alternative to invasive surgical procedures for abnormal uterine bleeding due to benign changes. Effective destruction of the endometrium during PDT requires a sufficient amount of light to be delivered to the entire endometrium in a reasonable time. To satisfy these criteria, we have developed a trifurcated optical applicator consisting of three cylindrical diffusing fibers. The applicator was inserted into freshly excised, intact human uteri and the optical distribution was measured with an isotropic fiber probe at various locations in the uterus. The results were in good agreement with the predictions of a mathematical model based on diffusion theory. The results indicate that irradiation of the endometrium by the trifurcated applicator can destroy tissue to a depth of 4 mm given an optical power of 100 mW per cm of diffusing tip (100 mW/cm) for an exposure time of less than 20 minutes.

Madsen, Steen J.; Svaasand, Lars O.; Fehr, Mathias K.; Tadir, Yona; Ngo, Phat; Tromberg, Bruce J.

1995-01-01

198

Solid state lasers for photodynamic therapy of malignant neoplasm  

NASA Astrophysics Data System (ADS)

This work demonstrates the possibility of treating animals with malignant neoplasms using 608 nm of laser radiation by means of photodynamic therapy (PDT). The intracavity transformation of the Nd:YAP main radiation 1079 nm was Raman converted in barium nitrate crystal, and the Stokes frequency (1216 nm) was doubled using KTP or RTA crystals. The LiF or Cr:YAG crystals are used for the Q-switch. The radiation parameters were obtained at 100 Hz pump repetition frequency. The average power at 608-nm radiation with LiF and KTP was 700 mW at multimode generation. The 3-6 single 10-15 ns pulses were generated during one cycle of pumping. The doubling efficiency with RTA was two times more than with KTP. The cells of Ehrlich adenocarcinoma (0.1 ml) were implanted in hind thighs of ICR white non-imbred mice. Photosensitizer HpD was i.v. administered in a dose of 10 mg/kg. Ten animals were treated (2 as a control). There was a 9-30% decrease in the tumor growth depending on the irradiation dose. The better result (30%) was for the 200 J/cm2 dose radiation. These results show the possibility of using all solid state lasers with wavelength of 608 nm for PDT.

Khulugurov, Vitaliy M.; Ivanov, Nikolai; Kim, Byoung-Chul; Mayorov, Alexander; Bordzilovsky, Dnitri; Masycheva, Valentina; Danilenko, Elena; Chung, Moon-Kwan

2002-05-01

199

Development and optimization of a diode laser for photodynamic therapy  

PubMed Central

Background and Aims: This study demonstrated the development of a laser system for cancer treatment with photodynamic therapy (PDT) based on a 635 nm laser diode. In order to optimize efficacy in PDT, the ideal laser system should deliver a homogeneous nondivergent light energy with a variable spot size and specific wavelength at a stable output power. Materials and Methods: We developed a digital laser beam controller using the constant current method to protect the laser diode resonator from the current spikes and other fluctuations, and electrical faults. To improve the PDT effects, the laser system should deliver stable laser energy in continuous wave (CW), burst mode and super burst mode, with variable irradiation times depending on the tumor type and condition. Results and Comments: The experimental results showed the diode laser system described herein was eminently suitable for PDT. The laser beam was homogeneous without diverging and the output power increased stably and in a linear manner from 10 mW to 1500 mW according to the increasing input current. Variation between the set and delivered output was less than 7%. Conclusions: The diode laser system developed by the author for use in PDT was compact, user-friendly, and delivered a stable and easily adjustable output power at a specific wavelength and user-set emission modes.

Lim, Hyun Soo

2011-01-01

200

Photodynamic therapy with fullerenes in vivo: reality or a dream?  

PubMed

Photodynamic therapy (PDT) employs the combination of nontoxic photosensitizers and visible light that is absorbed by the chromophore to produce long-lived triplet states that can carry out photochemistry in the presence of oxygen to kill cells. The closed carbon-cage structure found in fullerenes can act as a photosensitizer, especially when functionalized to impart water solubility. Although there are reports of the use of fullerenes to carry out light-mediated destruction of viruses, microorganisms and cancer cells in vitro, the use of fullerenes to mediate PDT of diseases such as cancer and infections in animal models is less well developed. It has recently been shown that fullerene PDT can be used to save the life of mice with wounds infected with pathogenic Gram-negative bacteria. Fullerene PDT has also been used to treat mouse models of various cancers including disseminated metastatic cancer in the peritoneal cavity. In vivo PDT with fullerenes represents a new application in nanomedicine. PMID:22122587

Sharma, Sulbha K; Chiang, Long Y; Hamblin, Michael R

2011-12-01

201

Five years experience of photodynamic therapy with new chlorin photosensitizer  

NASA Astrophysics Data System (ADS)

Clinical results of photodynamic therapy (PDT) with a novel natural second generation chlorin-type photosensitizer "Radachlorin", mainly consisting of sodium chlorine e6, are presented. This sensitizer possesses a number of advantages over sensitizers of hematoporphyrin and phthalocyanine types. In particular, Radachlorin is excreted from organism much faster (in 1-2 days), as a result the problem of patient light hypersensitivity for a few months is non-actual for Radachlorin. As light source there was used a 662 nm diode laser specially designed for PDT with Radachlorin. The 5 year clinical results of PDT application to 89 patients with different malignant tumors are summarized and analysed. It is shown in particular that PDT with Radachlorin is a radical high efficient method for treatment of basal cell carcinoma of skin. At intravenous introduction in drug dose 0.5 mg/kg with light fluence 300-350 J/cm2 or in dose 1 mg/kg with fluence 200-250 J/cm2 the method gives full recovery in almost 100% cases with excellent cosmetic effect. The method was successfully combined with surgical operations, laser ablations, radio- and chemotherapy. Preoperative and intraoperative PDT favors improvement of results in complex treatment of malignant tumors. The method has a potential as palliative measure; in a number of incurable cases it allowed us to achieve recanalization of obturated hollow organs, eliminate the inflammatory complications, and as a result to improve life quality.

Privalov, Valery A.; Lappa, Alexander V.; Kochneva, Elena V.

2005-08-01

202

Necrosis prediction of photodynamic therapy applied to skin disorders  

NASA Astrophysics Data System (ADS)

The great selectivity and the lack of side effects of Photodynamic Therapy make it more advantageous than radiotherapy or chemotherapy. The application of PDT to skin diseases is particularly appropriate, due to the accessibility of this tissue. Common disorders like nonmelanoma skin cancer, that includes basocelullar or squamous cell carcinomas, can be treated with PDT. Conventional procedures, like surgery or radiotherapy, are not so efficient and do not, in general, obtain the same favourable results. PDT in dermatology medical praxis uses fixed protocols depending on the photosensitizer and the optical source used. These protocols are usually provided by the photosensitizer laboratory, and every lesion is treated with the same parameters. In this work we present a photo-chemical model of PDT applied to skin disorders treated with topical photosensitizers. Optical propagation inside the tissue is calculated by means of a 3D diffusion equation, solved via a finite difference numerical method. The photosensitizer degradation or photobleaching is taken into account, as the drug looses efficiency with the irradiation time. With these data the necrosis area is estimated, so this model could be used as a predictive tool to adjust the optical power and exposition time for the particular disease under treatment.

Fanjul-Vélez, F.; Romanov, O. G.; López-Escobar, M.; Ortega-Quijano, N.; Arce-Diego, J. L.

2009-02-01

203

New approaches to photodynamic therapy of tumors with Al phthalocyanine  

NASA Astrophysics Data System (ADS)

The aim of the study was to determine the efficacy of photodynamic therapy (PDT) of tumors of different localization and histology with new photosensitizer aluminum sulfonated phthalocyanine (Photosense, Russia). PDT have been provided in 106 patients with different tumors. The initial dose (2.0 - 2.5 mg/kg) of PHS was significantly reduced till 0.5 - 0.8 mg/kg during clinical trials because of phototoxicity. The results of PDT, side effects and ways of their correction and prevention, as well as possibility to work out less toxic regimes of PDT with photosense, choice of laser and type of irradiation are discussed. Efficacy of PDT depended on tumor size and it's histological type. Using low doses of PHS we've reduced the phototoxicity of sensitizer with the same direct effectiveness of treatment. Undesirable changes in plasma content of antioxidants by means of high pressure liquid chromatography have been found in patients after PHS injection. Influence of short-term and long-term supplementation with beta- carotene and vitamin E on this parameters are discussed.

Vakoulovskaia, Elena G.; Chental, Victor V.; Kuvshinov, Yury P.; Poddubny, Boris K.

1999-12-01

204

Protoporphyrin IX for photodynamic therapy of brain tumours  

NASA Astrophysics Data System (ADS)

Protoporphyrin IX (PpIX) displays high tumour-selective uptake following oral administration of 5-aminolaevulinic acid (ALA), a fact that is being exploited for the fluorescence-guided resection (FGR) and photodynamic therapy (PDT) of human brain malignancies. A clinical procedure for interstitial PDT (iPDT) has been established including pre-treatment planning, optical fiber insertion under stereotactic guidance and therapeutic irradiation at non-thermal fluence rates. We have previously reported on median survival in the range of 15 months and the existence of some intriguing long-term survivors (>5 years) following iPDT. Such successful treatments rely on for example sufficient light, PpIX and oxygen levels. We have investigated the absolute PpIX concentration as well as the PDT-induced photobleaching kinetics in brain tissues. Tissue samples acquired during FGR contained PpIX concentrations up to 28 ?M. This observation implies that ALA-induced PpIX levels are sufficient for inducing PDT effects in viable tumour tissue upon therapeutic irradiation. However, regions of pre-existing necrosis were characterised by significantly lower photosensitiser levels. Fluorescence spectroscopy was implemented in parallel to iPDT with the aim to employ PpIX photobleaching as a tool for realtime treatment supervision and early treatment prognosis.

Johansson, A.; Kreth, F. W.; Ardeshiri, A.; Stummer, W.; Schnell, O.; Herms, J.; Palte, G.; Beyer, W.; Stepp, H.

2010-04-01

205

Measurement of photodynamic therapy drug concentrations in a tissue  

SciTech Connect

This is the final report of a one-year laboratory-directed research and development project at the Los Alamos National Laboratory (LANL). Photodynamic therapy (PDT) is an experimental treatment modality for cancer in which a photoactive molecule with an affinity for tumors in administered to the patient, then excited by light. Photoactivation creates singlet oxygen consequently killing the tissue. Knowledge of the concentration of the photoactive compound in the tissue is necessary for proper light dosimetry during PDT. Presently, the control of light application is problematic. If too much light is applied, damage to the surrounding tissue will occur. If insufficient light is applied, the targeted tissue volume will remain viable. The ideal implementation of PDT would use a feedback system for light delivery that incorporates the optical properties of the tissue and knowledge of the concentration of the photoactive compound. This project sought to develop a method for measuring photosensitizer concentrations in tissue phantoms that will lead to a noninvasive, endoscopically compatible, in vivo method of measuring PST drug concentrations.

Mourant, J.; Biglo, I.; Johnson, T.

1996-09-01

206

Absence of bacterial resistance following repeat exposure to photodynamic therapy  

NASA Astrophysics Data System (ADS)

The prevalence of antibiotic resistant bacteria necessitates exploration of alternative approaches to treat hospital and community acquired infections. The aim of this study was to determine whether bacterial pathogens develop resistance to antimicrobial photodynamic therapy (aPDT) during repeated sub-lethal challenge. Antibiotic sensitive and resistant strains of S. aureus and antibiotic sensitive E. coli were subjected to repeat PDT treatments using a methylene blue photosensitizer formulation and 670 nm illumination from a non-thermal diode laser. Parameters were adjusted such that kills were <100% so that surviving colonies could be passaged for subsequent exposures. With each repeat, kills were compared to those using non-exposed cultures of the same strain. Oxacillin resistance was induced in S. aureus using a disc diffusion method. For each experiment, "virgin" and "repeat" cultures were exposed to methylene blue at 0.01% w/v and illuminated with an energy dose of 20.6 J/cm2. No significant difference in killing of E. coli (repeat vs. virgin culture) was observed through 11 repeat exposures. Similar results were seen using MSSA and MRSA, wherein kill rate did not significantly differ from control over 25 repeat exposures. In contrast, complete oxacillin resistance could be generated in S. aureus over a limited number of exposures. PDT is effective in the eradication of pathogens including antibiotic resistance strains. Furthermore, repeated sub-lethal exposure does not induce resistance to subsequent PDT treatments. The absence of resistance formation represents a significant advantage of PDT over traditional antibiotics.

Pedigo, Lisa A.; Gibbs, Aaron J.; Scott, Robert J.; Street, Cale N.

2009-06-01

207

Photodynamic therapy on the ultrastructure of glioma cell  

NASA Astrophysics Data System (ADS)

OBJECTIVE ?the main purpose of this experiment was to study the change of C6 glioma cells' ultrastructure treated by photodynamic therapy(PDT), observe the change of morphology METHOD ?Make the model of rat glioma by transplanted C6 glioma cells into caudate nucleus?treated the glioma rat by PDT after two weeks. Observed the difference of subcellular structure before and after PDT by electron microscope. RESULT ? Apoptosis and necrosis can be seen after treated by PDT in the C6 glioma, basal membrance damaged ?number of cellular organ of endothelial cell of blood capillary declined?tight junction of endothelial cell lengthen and the gap enlarge. The PDT has slightly effect on the nomorl rat"s subcellular structue. CONCLUSION: PDT can induce the apoptosis and necrosis of C6 glioma cell. The damage of the ultramicrostructure of mitochondria and endoplasmic reticulum was the foundmentol of the change. PDT initiate the damage of BBB of the C6 glioma cell and weeken the function?and makes it a useful way of treating the glioma combained with chemotherapy.

Hu, Shaoshan; Zhang, Ruyou; Zheng, Yongri

2005-07-01

208

Photodynamic therapy for the treatment of acne: a pilot study.  

PubMed

Photodynamic therapy (PDT) with use of topical 5-aminolevulinic acid (ALA, Levulan Kerastick, Dusa Pharmaceuticals, Inc., Wilmington, MA) photosensitizing agent is a new modality for the treatment of acne. Eighteen patients (aged 15 to 63) with moderate to severe inflammatory acne received ALA-PDT. ALA remained in contact with skin for 15 to 30 minutes before exposure to blue light (ClearLight [Lumenis] or BLU-U [Dusa Pharmaceuticals, Inc.]) or the Aurora DSR (Syneron Medical Ltd.), which uses Electro-Optical Synergy (ELOS), a unique combination of optical and radiofrequency (RF) energy. Patients received two to four ALA-PDT treatments over four to eight weeks or two cycles of ALA-PDT (weeks 2, 4) preceded by salicylic acid peel (weeks 1, 3) over four weeks. The average follow-up time was four months. On a scale of 0.0 to 4.0, the average acne grade improvement was 1.75. Among the 12 patients who said their acne had improved, 11 had at least 50% improvement and five had more than 75% improvement. Adverse effects were limited to erythema and peeling for up to five days after treatment and one episode of impetiginization of the affected area. Patients with moderate to severe acne can achieve durable improvement with short-contact ALA-PDT. PMID:15624736

Taub, Amy Forman

209

Endodontic antimicrobial photodynamic therapy: Safety assessment in mammalian cell cultures  

PubMed Central

Objectives To assess the in vitro synergistic effect of methylene blue (MB) and red light on human gingival fibroblasts and osteoblasts with parameters similar to those that may be applied in a clinical setting for endodontic disinfection. Materials and Methods Both cell types were sensitized with 50 ?g/ml MB followed by exposure to red light at 665 nm for 5 minutes with an irradiance of 10, 20 and 40 mW/cm2. Following photodynamic therapy (PDT), cell viability and mitochondrial activity were evaluated by the neutral red and MTT assay, respectively. Assessment of PDT-induced apoptosis was investigated by western blot analysis using cleaved poly(ADP-ribose) polymerase - specific antibodies. Results Light at 20 and 40 mW/cm2 with MB had modest effects at 24 hours on osteoblasts in both assays, whereas sodium hypochlorite (NaOCl) completely eliminated cells. Western blot analysis revealed no signs of apoptosis in either cell type. Conclusion The data suggest that there is a safe therapeutic window whereby PDT can inactivate endodontic pathogens without affecting host cell viability.

Xu, Yan; Young, Mark J.; Battaglino, Ricardo A.; Morse, Leslie R.; Fontana, Carla Raquel; Pagonis, Tom C.; Kent, Ralph; Soukos, Nikolaos S.

2009-01-01

210

Adjuvant Therapy for Gallbladder Carcinoma: The Mayo Clinic Experience  

SciTech Connect

Purpose: To analyze the effect of adjuvant chemoradiotherapy on gallbladder carcinoma. Methods and Materials: We retrospectively reviewed the records from consecutive patients who underwent R0 resection of gallbladder carcinoma between January 1, 1985, and December 31, 2004. Patients had either Stage I (T1-T2N0M0) or Stage II (T3N0M0 or T1-T3N1M0) disease. Patients undergoing adjuvant therapy received 5-fluorouracil chemotherapy concurrently with radiotherapy (median dosage, 50.4 Gy in 28 fractions). Adverse prognostic factors and the effect of adjuvant treatment on overall survival (OS) were evaluated. Results: A total of 73 patients were included in the analysis; of these, 25 received adjuvant chemoradiotherapy. On univariate analysis, no adverse prognostic factors for OS reached statistical significance, but trends were noted for Stage N1 vs. N0 (p = .06), Nx vs. N0 (p = .09), Stage T3 vs. T1-T2 (p = .06), and histologic findings other than adenocarcinoma (p = .13). The median OS for patients receiving adjuvant chemoradiotherapy vs. surgery alone was 4.8 years and 4.2 years, respectively (log-rank test, p = .56). However, a significantly greater percentage of patients receiving adjuvant chemoradiotherapy had Stage II disease (p <.001). In the multivariate Cox model, increasing T and N category and histologic findings other than adenocarcinoma were significant predictors of decreased OS. Additionally, adjuvant chemoradiotherapy was a significant predictor of improved OS after adjusting for these prognostic factors (hazard ratio for death, 0.3; 95% confidence interval, 0.13-0.69; p = .004). Conclusion: After adjusting for the stage parameters and histologic findings, our data suggest that adjuvant chemoradiotherapy might improve OS for patients with gallbladder cancer.

Gold, Douglas G. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Miller, Robert C. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)], E-mail: miller.robert@mayo.edu; Haddock, Michael G. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Gunderson, Leonard L. [Department of Radiation Oncology, Mayo Clinic, Scottsdale, Arizona (United States); Quevedo, Fernando [Division of Medical Oncology, Mayo Clinic, Rochester, Minnesota (United States); Donohue, John H. [Division of Gastroenterologic and General Surgery, Mayo Clinic, Rochester, Minnesota (United States); Bhatia, Sumita [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Nagorney, David M. [Division of Gastroenterologic and General Surgery, Mayo Clinic, Rochester, Minnesota (United States)

2009-09-01

211

Potentiation of thermal inactivation of glyceraldehyde-3-phosphate dehydrogenase by photodynamic treatment. A possible model for the synergistic interaction between photodynamic therapy and hyperthermia.  

PubMed Central

Thermal inactivation of glyceraldehyde-3-phosphate dehydrogenase appeared to be caused by a conformational mechanism, without involvement of covalent reactions. On the other hand, photodynamic inactivation of the enzyme (induced by illumination in the presence of Photofrin II) was caused by photo-oxidation of the essential thiol group in the active centre. A short photodynamic treatment of the enzyme, leading to only a limited inactivation, caused a pronounced potentiation of subsequent thermal inactivation, as measured over the temperature range 40-50 degrees C. Analysis of the experimental results according to the Arrhenius equation revealed that both the activation energy of thermal inactivation and the frequency factor (the proportionality constant) were significantly decreased by the preceding photodynamic treatment. The experimental results indicate a mechanism in which limited photodynamic treatment induced a conformational change of the protein molecule. This conformational change did not contribute to photodynamic enzyme inhibition, but was responsible for the decreased frequency factor and activation energy of subsequent thermal inactivation of the enzyme. The opposing effects of decreased activation energy and decreased frequency factor resulted in potentiation of thermal inactivation of the enzyme over the temperature range 40-50 degrees C. With other proteins, different results were obtained. With amylase the combined photodynamic and thermal effects were not synergistic, but additive, and photodynamic treatment had no effect on the frequency factor and the activation energy of thermal inactivation. With respect to myoglobin denaturation, the photodynamic and thermal effects were antagonistic over the whole practically applicable temperature range. Limited photodynamic treatment protected the protein against heat-induced precipitation, concomitantly increasing both the frequency factor and the activation energy of the process. These results offer a model for one of the possible mechanisms of synergistic interaction between photodynamic therapy and hyperthermia in cancer treatment.

Prinsze, C; Dubbelman, T M; Van Steveninck, J

1991-01-01

212

Photodynamic therapy for localized infections - state of the art  

PubMed Central

Photodynamic therapy (PDT) was discovered over one hundred years ago by observing the killing of microorganisms when harmless dyes and visible light were combined in vitro. Since then it has primarily been developed as a treatment for cancer, ophthalmologic disorders and in dermatology. However in recent years interest in the antimicrobial effects of PDT has revived and it has been proposed as a therapy for a large variety of localized infections. This revival of interest has largely been driven by the inexorable increase in drug resistance amongst many classes of pathogen. Advantages of PDT include equal killing effectiveness regardless of antibiotic resistance, and a lack of induction of PDT resistance. Disadvantages include the cessation of the antimicrobial effect when the light is turned off, and less than perfect selectivity for microbial cells over host tissue. This review will cover the use of PDT to kill or inactivate pathogens in ex vivo tissues and in biological materials such as blood. PDT has been successfully used to kill pathogens and even to save life in several animal models of localized infections such as surface wounds, burns, oral sites, abscesses and the middle ear. A large number of clinical studies of PDT for viral papillomatosis lesions and for acne refer to its anti-microbial effect, but it is unclear how important this microbial killing is to the overall therapeutic outcome. PDT for periodontitis is a rapidly growing clinical application and other dental applications are under investigation. PDT is being clinically studied for other dermatological infections such as leishmaniasis and mycobacteria. Antimicrobial PDT will become more important in the future as antibiotic resistance is only expected to continue to increase.

Dai, Tianhong; Huang, Ying-Ying; Hamblin, Michael R

2009-01-01

213

Induction of Immune Mediators in Glioma and Prostate Cancer Cells by Non-Lethal Photodynamic Therapy  

Microsoft Academic Search

BackgroundPhotodynamic therapy (PDT) uses the combination of photosensitizing drugs and harmless light to cause selective damage to tumor cells. PDT is therefore an option for focal therapy of localized disease or for otherwise unresectable tumors. In addition, there is increasing evidence that PDT can induce systemic anti-tumor immunity, supporting control of tumor cells, which were not eliminated by the primary

Robert Kammerer; Alexander Buchner; Patrick Palluch; Thomas Pongratz; Konstantin Oboukhovskij; Wolfgang Beyer; Ann Johansson; Herbert Stepp; Reinhold Baumgartner; Wolfgang Zimmermann; Joseph Najbauer

2011-01-01

214

Predicting benefit from adjuvant therapy in colon cancer  

Microsoft Academic Search

Colorectal cancer is a significant cause of morbidity and mortality despite recent advances in therapy. Given the variety\\u000a of options that exist for treatment of metastatic colorectal cancer and the fact that resistance to any single approach is\\u000a common, the need to identify predictors of response to specific therapies is urgent. This need is particularly critical in\\u000a the adjuvant setting

Crystal S. Denlinger; Neal J. Meropol

2007-01-01

215

Early-stage thymic carcinoma: is adjuvant therapy required?  

PubMed Central

Although the prognosis of advanced thymic carconoma remains poor, previous reports have shown survival rates of 70% to 100% in patients with Masaoka stage I or stage II of the disease who were treated with surgery followed by adjuvant therapy. However, the role of adjuvant therapy in these stages is controversial. We retrospectively evaluated the outcome of 4 patients with Masaoka stage II thymic carcinoma who were treated with surgery alone between 1992 and 2008. No patient had stage I of the disease. Primary tumors were preoperatively evaluated by chest X-ray and computed tomography. Needle biopsy was not performed because the tumors were clinically diagnosed as noninvasive thymomas. The largest diameter of the primary tumor was 65 mm. Mediastinal lymphadenopathy was not detected by computed tomography. All patients underwent transsternal thymectomy. Mediastinal lymph node dissection was not performed. None of the patients received adjuvant chemotherapy and/or irradiation. Histopathologic examination revealed squamous cell carcinoma in 3 patients and undifferentiated carcinoma in one. Pathologic invasion to the adjacent organs or lymph node metastasis was not detected. All patients were alive and free from relapse at a follow-up of 72 months (range, 12-167 months). Radical resection without adjuvant therapy could be a treatment option for early Masaoka stage thymic carcinoma with low-grade histology.

Onuki, Takuya; Inagaki, Masaharu; Yamaoka, Masatoshi; Kitazawa, Shinsuke; Kobayashi, Keisuke; Iguchi, Kesato; Kikuchi, Shinji; Goto, Yukinobu; Onizuka, Masataka; Sato, Yukio

2013-01-01

216

Early-stage thymic carcinoma: is adjuvant therapy required?  

PubMed

Although the prognosis of advanced thymic carconoma remains poor, previous reports have shown survival rates of 70% to 100% in patients with Masaoka stage I or stage II of the disease who were treated with surgery followed by adjuvant therapy. However, the role of adjuvant therapy in these stages is controversial. We retrospectively evaluated the outcome of 4 patients with Masaoka stage II thymic carcinoma who were treated with surgery alone between 1992 and 2008. No patient had stage I of the disease. Primary tumors were preoperatively evaluated by chest X-ray and computed tomography. Needle biopsy was not performed because the tumors were clinically diagnosed as noninvasive thymomas. The largest diameter of the primary tumor was 65 mm. Mediastinal lymphadenopathy was not detected by computed tomography. All patients underwent transsternal thymectomy. Mediastinal lymph node dissection was not performed. None of the patients received adjuvant chemotherapy and/or irradiation. Histopathologic examination revealed squamous cell carcinoma in 3 patients and undifferentiated carcinoma in one. Pathologic invasion to the adjacent organs or lymph node metastasis was not detected. All patients were alive and free from relapse at a follow-up of 72 months (range, 12-167 months). Radical resection without adjuvant therapy could be a treatment option for early Masaoka stage thymic carcinoma with low-grade histology. PMID:23585943

Sakai, Mitsuaki; Onuki, Takuya; Inagaki, Masaharu; Yamaoka, Masatoshi; Kitazawa, Shinsuke; Kobayashi, Keisuke; Iguchi, Kesato; Kikuchi, Shinji; Goto, Yukinobu; Onizuka, Masataka; Sato, Yukio

2013-04-01

217

Photodynamic therapy: computer modeling of diffusion and reaction phenomena  

NASA Astrophysics Data System (ADS)

We have developed a transient, one-dimensional mathematical model for the reaction and diffusion phenomena that occurs during photodynamic therapy (PDT). This model is referred to as the PDTmodem program. The model is solved by the Crank-Nicholson finite difference technique and can be used to predict the fates of important molecular species within the intercapillary tissue undergoing PDT. The following factors govern molecular oxygen consumption and singlet oxygen generation within a tumor: (1) photosensitizer concentration; (2) fluence rate; and (3) intercapillary spacing. In an effort to maximize direct tumor cell killing, the model allows educated decisions to be made to insure the uniform generation and exposure of singlet oxygen to tumor cells across the intercapillary space. Based on predictions made by the model, we have determined that the singlet oxygen concentration profile within the intercapillary space is controlled by the product of the drug concentration, and light fluence rate. The model predicts that at high levels of this product, within seconds singlet oxygen generation is limited to a small core of cells immediately surrounding the capillary. The remainder of the tumor tissue in the intercapillary space is anoxic and protected from the generation and toxic effects of singlet oxygen. However, at lower values of this product, the PDT-induced anoxic regions are not observed. An important finding is that an optimal value of this product can be defined that maintains the singlet oxygen concentration throughout the intercapillary space at a near constant level. Direct tumor cell killing is therefore postulated to depend on the singlet oxygen exposure, defined as the product of the uniform singlet oxygen concentration and the time of exposure, and not on the total light dose.

Hampton, James A.; Mahama, Patricia A.; Fournier, Ronald L.; Henning, Jeffery P.

1996-04-01

218

Photodynamic therapy: a new antimicrobial approach to infectious disease?  

PubMed Central

Photodynamic therapy (PDT) employs a non-toxic dye, termed a photosensitizer (PS), and low intensity visible light which, in the presence of oxygen, combine to produce cytotoxic species. PDT has the advantage of dual selectivity, in that the PS can be targeted to its destination cell or tissue and, in addition, the illumination can be spatially directed to the lesion. PDT has previously been used to kill pathogenic microorganisms in vitro, but its use to treat infections in animal models or patients has not, as yet, been much developed. It is known that Gram-(?) bacteria are resistant to PDT with many commonly used PS that will readily lead to phototoxicity in Gram-(+) species, and that PS bearing a cationic charge or the use of agents that increase the permeability of the outer membrane will increase the efficacy of killing Gram-(?) organisms. All the available evidence suggests that multi-antibiotic resistant strains are as easily killed by PDT as naïve strains, and that bacteria will not readily develop resistance to PDT. Treatment of localized infections with PDT requires selectivity of the PS for microbes over host cells, delivery of the PS into the infected area and the ability to effectively illuminate the lesion. Recently, there have been reports of PDT used to treat infections in selected animal models and some clinical trials: mainly for viral lesions, but also for acne, gastric infection by Helicobacter pylori and brain abcesses. Possible future clinical applications include infections in wounds and burns, rapidly spreading and intractable soft-tissue infections and abscesses, infections in body cavities such as the mouth, ear, nasal sinus, bladder and stomach, and surface infections of the cornea and skin.

Hasan, Tayyaba

2011-01-01

219

5-Aminolaevulinic acid peptide prodrugs enhance photosensitization for photodynamic therapy.  

PubMed

Intracellular porphyrin generation following administration of 5-aminolaevulinic acid (ALA) has been widely used in photodynamic therapy for a range of malignant and nonmalignant lesions. However, ALA is relatively hydrophilic and lacks stability at physiologic pH, limiting its bioavailability. We have investigated more lipophilic, uncharged ALA-peptide prodrugs based on phenylalanyl-ALA conjugates, which are water soluble and chemically stable for improving ALA delivery. Pharmacokinetics of the induced protoporphyrin IX (PpIX) were studied in transformed PAM212 keratinocyte cells and pig skin explants. The intracellular porphyrin production was substantially increased with Ac-L-Phe-ALA-Me (compound 1) and Ac-L-Phe-ALA (compound 3) compared with equimolar ALA: after 6-h incubation, the PpIX fluorescence measured using 0.01 mmol/L of compound 1 was enhanced by a factor of 5 compared with ALA. Phototoxicity results showed good correlation with PpIX levels, giving a LD(50) (2.5 J/cm(2)) of 25 micromol/L for ALA, 6 micromol/L for 5-aminolaevulinic hexyl ester, and 2.6 micromol/L for compound 1, which exhibited the highest phototoxicity. However, these results were stereospecific because the corresponding D-enantiomer, Ac-D-Phe-ALA-Me (compound 2), induced neither porphyrin synthesis nor phototoxicity. PpIX levels were considerably reduced when cells were incubated with compound 1 at low temperatures, consistent with active transport. In pig skin explants, compound 1 induced higher porphyrin fluorescence than ALA by a factor of 3. These results show that water-soluble peptide prodrugs of ALA can greatly increase its cellular uptake, generating more intracellular PpIX and improved tumor cell photosensitization. The derivatives are comparable in efficacy with 5-aminolaevulinic hexyl ester but less toxic and more stable at physiologic pH. PMID:18566243

Bourré, Ludovic; Giuntini, Francesca; Eggleston, Ian M; Wilson, Michael; MacRobert, Alexander J

2008-06-01

220

Assessing autophagy in the context of photodynamic therapy  

PubMed Central

Photodynamic therapy (PDT) is a procedure that has applications in the selective eradication of neoplasia where sites of malignant lesions are clearly delineated. It is a two-step process whereby cells are first sensitized to light and then photoirradiated. This results in the formation of singlet molecular oxygen and other reactive oxygen species that can cause photodamage at sites where the photosensitizing agent has localized. Photosensitizers found to be clinically useful show affinity for the endoplasmic reticulum (ER), mitochondria, lysosomes, or combinations of these sites. The induction of apoptosis and/or autophagy in photosensitized cells is a common outcome of PDT. This report explores the following issues: (1) Does the induction of autophagy in PDT protocols occur independent of, or in association with, apoptosis? (2) Does the resulting autophagy play a prosurvival or prodeath role? (3) Do photosensitizers damage/inactivate specific proteins that are components of, or that modulate the autophagic process? (4) Can an autophagic response be mounted in cells in which lysosomes are specifically photodamaged? In brief, autophagy can occur independently of apoptosis in PDT protocols, and appears to play a prosurvival role in apoptosis competent cells, and a prodeath role in apoptosis incompetent cells. Mitochondrial and ER-localized sensitizers cause selective photodamage to some (i.e., Bcl-2, Bcl-xL, mTOR) proteins involved in the apoptotic/autophagic process. Finally, an aborted autophagic response occurs in cells with photodamaged lysosomes. Whereas autophagosomes form, digestion of their cargo is compromised because of the absence of functional lysosomes.

Reiners, John J.; Agostinis, Patrizia; Berg, Kristian; Oleinick, Nancy L.; Kessel, David

2010-01-01

221

Outcome of pancreaticoduodenectomy and impact of adjuvant therapy for ampullary carcinomas  

Microsoft Academic Search

Purpose: To determine the clinical outcomes and potential impact of adjuvant chemoradiation in patients undergoing surgical resection of ampullary carcinoma.Patients and Methods: Between 1988 and 1997, 39 patients underwent pancreaticoduodenectomy for ampullary adenocarcinomas. Clinical and pathologic factors, adjuvant therapy records, and disease status were obtained from chart review. Thirteen (33%) patients received adjuvant chemoradiation. Radiation therapy was delivered to the

Jason H Lee; Richard Whittington; Noel N Williams; Mark F Berry; David J Vaughn; Daniel G Haller; Ernest F Rosato

2000-01-01

222

Adjuvant endocrine therapy for perimenopausal women with early breast cancer.  

PubMed

Adjuvant treatment with aromatase inhibitors (AIs) improves outcomes in postmenopausal women with hormone-sensitive early breast cancer compared with tamoxifen. However, AIs should not be used in premenopausal women because they can paradoxically increase estrogen secretion and may therefore stimulate tumor progression. In perimenopausal women undergoing treatment for breast cancer, it can be difficult to determine true menopausal status because adjuvant chemotherapy, tamoxifen, and gonadotropin-releasing hormone analogues can induce transient (or permanent) ovarian suppression. How can one determine whether these women are truly postmenopausal and therefore candidates for AI therapy? A panel of experts in the field of endocrine therapy in breast cancer met in Dubrovnik, Croatia, on October 23, 2006, to discuss this clinical dilemma. This report summarizes the conclusions and recommendations that arose from this discussion. PMID:19036588

Ortmann, Olaf; Cufer, Tanja; Dixon, J Michael; Maass, Nicolai; Marchetti, Paolo; Pagani, Olivia; Pronzato, Paolo; Semiglazov, Vladimir; Spano, Jean-Philippe; Vrdoljak, Eduard; Wildiers, Hans

2008-11-26

223

Phytotherapeutic and naturopathic adjuvant therapies in otorhinolaryngology.  

PubMed

Phytotherapeutic pharmaceuticals and herbal medicinal products with its roots in classical phytotherapeutic medicine have a well-established role in otolaryngological therapy, especially for diseases of the upper airways and acute and chronic infections. A thorough selection and application could mean huge benefit for the patient, in particular in cases with contraindications, chemo- and antibiotic resistance or patient request. Besides, it might spare other medications. Phytotherapeutic pharmaceuticals must fulfil the same criteria of quality, effectiveness and harmlessness of evidence-based medicine like chemical pharmaceuticals, although they are often prescribed due to its well established or traditional based use. This review focuses on phytotherapeutic therapies well established within the European Community for otolaryngologic disease patterns by referring to clinical studies or meta-analysis. PMID:21922427

Ciuman, Raphael Richard

2011-09-16

224

Potentiation of Photodynamic Therapy by Ursodeoxycholic Acid1  

Microsoft Academic Search

Ursodeoxycholic acid (UDCA) protects cells from the apoptotic effects of hydrophobic bile acids and some other cytotoxic agents. We observed the opposite result when assessing the effects of UDCA on the apoptotic response to mitochondrial photodamage induced by photodynamic ther- apy (PDT). Two photosensitizers with predominantly mitochondrial spec- ificity were used: a porphycene we have designated CPO; and the tin

David Kessel; Joseph A. Caruso; John J. Reiners

2000-01-01

225

Hybrid photoactive fullerene derivative-ruboxyl nanostructures for photodynamic therapy.  

PubMed

Here we report the investigation of photophysical properties and photodynamic action of two novel water soluble hybrid molecular structures based on [60]fullerene dyads bearing covalently attached residues of anthracycline antibiotic "ruboxyl". Molecular structures of the designed compounds were confirmed by IR and UV-VIS absorption spectroscopy, electrospray mass spectrometry (compound 5), and (1)H and (13)C NMR spectroscopy. Dynamic light scattering, steady-state and kinetic fluorimetry and UV-VIS absorption spectroscopy techniques were used to study the behavior of the synthesized hybrid molecular structures in aqueous solutions. Photodynamic activity of the compounds was evaluated by monitoring the O2(-) generation under visible light irradiation using the NBT test. It has been shown that the anthracycline chromophore (ruboxyl moiety possesses no photodynamic activity) behaves as an efficient photosensitizer for the fullerene core operating via the energy and/or the electron transfer pathways. The presented approach opens up wide opportunities for the design of various fullerene-based donor-acceptor systems with enhanced photodynamic properties potentially suitable for biomedicinal applications. PMID:23712714

Kotelnikov, Alexander I; Rybkin, Alexander Yu; Khakina, Ekaterina A; Kornev, Alexey B; Barinov, Alexander V; Goryachev, Nikolay S; Ivanchikhina, Anastasiya V; Peregudov, Alexander S; Martynenko, Vyacheslav M; Troshin, Pavel A

2013-05-28

226

Light dosimetry in vivo in interstitial photodynamic therapy of human tumors  

Microsoft Academic Search

Photodynamic therapy, developed since 1961 with Lipson's studies, is now limited in its clinical applications by the lack of knowledge about light comportment and the action of hematoporphyrin in tissues. Using human tumor models in mice, the intratumoral light flux was measured during an interstitial illumination (cylindrical diffusor 5 mm of length) by an argon dye laser emitting continuously at

Anne M. Reynes; Simon Diebold; Dominique Lignon; Yves Granjon; Francois H. Guillemin

1991-01-01

227

Photodynamic Therapy With Motexafin Lutetium Induces Redox-Sensitive Apoptosis of Vascular Cells  

Microsoft Academic Search

Motexafin lutetium is a photosensitizer that accumulates in atherosclerotic plaque and, after activation by far-red light, produces cytotoxic singlet oxygen. The combination of photosensitizer and illumination, known as photodynamic therapy (PDT), has been shown to reduce atheroma formation in animal models and is under clinical investigation. However, the effects of PDT with motexafin lutetium on isolated vascular cells are unknown.

Zhiping Chen; Kathryn W. Woodburn; Can Shi; Daniel C. Adelman; Campbell Rogers; Daniel I. Simon

2010-01-01

228

Mapping of oxidative stress responses of human tumor cells following photodynamic therapy using hexaminolevulinate  

Microsoft Academic Search

BACKGROUND: Photodynamic therapy (PDT) involves systemic or topical administration of a lesion-localizing photosensitizer or its precursor, followed by irradiation of visible light to cause singlet oxygen-induced damage to the affected tissue. A number of mechanisms seem to be involved in the protective responses to PDT, including activation of transcription factors, heat shock proteins, antioxidant enzymes and apoptotic pathways. RESULTS: In

Lina Cekaite; Qian Peng; Andrew Reiner; Susan Shahzidi; Siri Tveito; Ingegerd E Furre; Eivind Hovig

2007-01-01

229

Telemetric light delivery and monitoring system for photodynamic therapy based on solid-state optodes  

Microsoft Academic Search

Light delivery and optical monitoring during photodynamic therapy (PDT) is often limited by the need for a physical optical link between the light source and detection devices and the treatment volume. This can be critical when sources need to be implanted within the body for extended periods. We report on the latest developments for a telemetric PDT delivery and monitoring

Eduardo Margallo-Balbás; Johan G. Kaptein; Henricus J. C. M. Sterenborg; Grégory Pandraud; Patrick J. French; Dominic J. Robinson

2008-01-01

230

Photodynamic therapy of early stage cancer of lung, esophagus, and stomach with two different photosensitizers  

NASA Astrophysics Data System (ADS)

The paper presents the results of photodynamic therapy (PDT) of early-stage cancer of lung (17 patients), esophagus (8 patients) and stomach (10 patients). Fifteen patients had second primary tumors. New drugs photoheme and photosens were used as photosensitizers. Complete remission was obtained in 87%. The patients are followed up without relapses to 2.5 years.

Chissov, Valery I.; Sokolov, Victor V.; Trakhtenberg, A. K.; Mamontov, A. S.; Vaschakmadze, L. A.; Frank, G. A.; Filonenko, E. V.; Telegina, L. V.; Belous, T. A.; Gladunov, V. K.; Aristarkhova, E. I.; Zharkova, Natalja N.; Menenkov, V. D.

1996-01-01

231

Photodynamic Therapy of Vulvar Intraepithelial Neoplasia III Using Topically Applied 5-Aminolevulinic Acid  

Microsoft Academic Search

Objectives. The aim of this study was twofold: first, to determine the feasibility of photodynamic therapy (PDT) of vulvar intraepithelial neoplasia III (VIN III) using topically applied 5-aminolevulinic acid (ALA) for photosensitization, and second, to compare PDT results with those of laser evaporation and local excision.Methods. Fifteen patients with VIN III had 10 g of 10% ALA gel applied to

Mathias K. Fehr; René Hornung; Viola A. Schwarz; René Simeon; Urs Haller; Pius Wyss

2001-01-01

232

Combined near infrared photothermolysis and photodynamic therapy by association of gold nanoparticles and an organic dye  

Microsoft Academic Search

We investigated the combination of near infrared (NIR) photothermolysis and photodynamic therapy against different models of bacteria (S. aureus, S. epidermidis both methicillin susceptible and resistant), in order to discover possible synergistic pathways in the fight against cancer. Photothermolysis was mediated by NIR light absorption from gold nanorods, which were coated with polyethylene glycol to gain biocompatibility and provide for

Elena S. Tuchina; Fulvio Ratto; Boris N. Khlebtsov; Sonia Centi; Paolo Matteini; Francesca Rossi; Franco Fusi; Nikolai G. Khlebtsov; Roberto Pini; Valery V. Tuchin

2011-01-01

233

Treatment modes and clinical experiment of medical robot assisted photodynamic therapy of port wine stains  

Microsoft Academic Search

Port wine stains (PWS) are congenital vascular malformations, which usually appear at birth. Photodynamic therapy (PDT) is an effective approach in the treatment of PWS with laser. In clinical, the laser power density of laser spot used in PDT treatment is uneven and doctors need to keep moving laser fiber manually to uniformize laser irradiation, which is arbitrary and un-quantified,

Xing-tao Wang; Xing-guang Duan; Qiang Huang; Gui-bin Bian; Hong-hua Zhao; Nai-yan Huang; Ying Gu

2010-01-01

234

Histological findings of surgically excised choroidal neovascular membranes after photodynamic therapy  

Microsoft Academic Search

AIMTo investigate effects of photodynamic therapy (PDT) on human choroidal neovascularisation (CNV).METHODSTwo patients with recurrences after PDT with verteporfin underwent surgical extraction of the CNV. Immediately after surgical excision the subfoveal neovascular membranes were divided for light microscopic and for electron microscopic processing. For light microscopy tissues were embedded in paraffin. Sections were stained with haematoxylin and eosin, and the

U E K Schnurrbusch; K Welt; L-C Horn; P Wiedemann; S Wolf

2001-01-01

235

Assembly of catalase-based bioconjugates for enhanced anticancer efficiency of photodynamic therapy in vitro.  

PubMed

An oxygen generation core-shell structure uploading rose bengal has been fabricated by covalent assembly of catalase and alginate dialdehyde via Schiff's base. The composite can catalyze the decomposition of intracellular H2O2 to increase the concentration of O2, which effectively enhances the anticancer efficiency of photodynamic therapy in vitro. PMID:24104860

Zhao, Jie; Fei, Jinbo; Du, Cuiling; Cui, Wei; Ma, Hongchao; Li, Junbai

2013-10-22

236

Photodynamic Therapy with Verteporfin for Polypoidal Choroidal Vasculopathy of the Macula  

Microsoft Academic Search

Purpose: Indications for photodynamic therapy (PDT) have increased from age-related macular degeneration with choroidal neovascularization (CNV), containing more than 50% of the classic component, to occult CNV, myopic CNV and CNV due to ocular histoplasmosis syndrome. In the present study, the effect of PDT with verteporfin was examined in polypoidal choroidal vasculopathy (PCV) of the macula. Methods: PDT was performed

Sung Chul Lee; Youl Seok Seong; Sung Soo Kim; Hyung Jun Koh; Oh Woong Kwon

2004-01-01

237

Photodynamic therapy for treatment of AIDS-related mucocutaneous Kaposi's sarcoma (Invited Paper)  

NASA Astrophysics Data System (ADS)

Since 1975, Phase I/II studies have demonstrated the successfulness of hematoporphyrin derivative photodynamic therapy (PDT) in the treatment of various malignancies of the skin, eye, bladder, lung, and head and neck. Moreover, in 1981 two cases of traditional Western cutaneous Kaposi's sarcoma (TKS) have been treated with photodynamic therapy with both early and late complete response. To date, attempts to cure and palliation of the more aggressive AIDS-related oral Kaposi's sarcoma with conventional radiation, chemotherapy or immunotherapy, or surgical excision have been limited and often associated with debilitating mucositis and further immunosuppression. Certain aspects of photodynamic therapy may be efficacious for treatment of mucocutaneous Kaposi's sarcoma: (1) the selective retention of hematoporphyrin derivative by neoplastic lesions (endothelial cell tumors); (2) a tumor- specific cytotoxic agent (i.e., free oxygen radical); (3) absence of systemic toxicity from immunosuppression; (4) the potential for retreatment without increasing side effects; and (5) porphyrin-mediated photoinactivation of enveloped viruses. Herein presented are seven cases of AIDS-related KS (EKS) with diffuse, superficial, and nodular mucocutaneous lesions treated with dihematoporphyrin derivative and photodynamic therapy with subsequent dramatic early partial and complete responses.

Schweitzer, Vanessa G.

1992-06-01

238

A novel medical robot assisting photodynamic therapy for port wine stains  

Microsoft Academic Search

Port wine stain (PWS) birthmarks are congenital vascular malformations, which usually appear at birth and tend to become darker and thicker with age's growth. Vasculartargeted photodynamic therapy (PDT) is an effective approach in the treatment of PWS. However, due to the arbitrariness of manual operation and pole points existing in laser radiation, the PWS zone was always cured unevenly in

Gui-bin Bian; Xing-guang Duan; Qiang Huang; Xing-tao Wang; Shi-hu Cui; Naiyan Huang; Ying Gu

2010-01-01

239

The influence of intravesical photodynamic therapy on subsequent bladder irradiation tolerance  

Microsoft Academic Search

The aim of this project was to measure the irradiation tolerance of normal (non tumour bearing) mouse bladder after previous intravesical photodynamic therapy (PDT). Illumination with a range of light doses at 24 h after Photofrin was used as the initial PDT treatment and irradiation with a range of X-ray doses was given at 12 or 24 weeks after the

J. G. Post; J. A. M. te Poele; Y. Oussoren; F. A. Stewart

1995-01-01

240

The changes of multifocal electroretinography in the early stage of photodynamic therapy for choroidal neovascularization  

Microsoft Academic Search

To investigate short-term changes in the multifocal electroretinography (ERG) recordings after photodynamic therapy (PDT) for choroidal neovascularization (CNV), 16 patients (17 eyes) with classic CNV confirmed by fluorescein angiography (FA) and indocyanine green angiography (ICGA), including 11 cases (12 eyes) of exudative age-related macular degeneration (AMD), two cases (two eyes) of pathological myopia and three cases (three eyes) of idiopathic

Libin Jiang; Chenjin Jin; Feng Wen; Shizhou Huang; Dezheng Wu; Lezheng Wu

2003-01-01

241

Spatial measurement of oxygen levels during photodynamic therapy using time-resolved optical spectroscopy  

Microsoft Academic Search

Tissue oxygenation is one of the key dosimetric factors involved in the application of photodynamic therapy (PDT). However, quantitative studies of oxygenation levels at and surrounding the treatment site have been lacking both before, during and after treatment. With the recent development of sensitive, non-invasive, optical spectroscopic techniques based on oxygen-dependent phosphorescence quenching of probe compounds, oxygenation levels can now

B. W. Mcllroy; A. Curnow; G. Buonaccorsi; M. A. Scott; S. G. Bown; A. J. MacRobert

1998-01-01

242

Photodynamic therapy for port wine stains assisted by a novel robotic system  

Microsoft Academic Search

Port wine stains (PWS) is a vascular malformation consisting of dilated capillaries in the superficial dermis. Photodynamic therapy (PDT) is an effective approach in the treatment of PWS. However, the procedure of treatment is a low efficient and hard work, as the doctor need to hold laser fiber to irradiate for 20 min to 50 min per lesion. So an

Naiyan Huang; Jianguo Zhu; Ying Wang; Guibin Bian; Xingguang Duan; Weifeng Liu; Xiaoying Tang; Xingtao Wang; Shihu Cui; Chunyu Zhang; Ying Gu

2010-01-01

243

Photodynamic Therapy of Skin Cancers: Sensitizers, Clinical Studies and Future Directives  

Microsoft Academic Search

Photodynamic therapy (PDT) is a new modality of skin cancer treatment. It involves the administration of photosensitizing drugs which, when localized in tumor tissue can produce its destruction by absorbing an adequate dose of light of an appropriate wavelength. A large number of photosensitizing agents have been tested in PDT experiments. Topical application of 5-aminolevulinic acid (5-ALA) followed by light

Fernanda S. De Rosa; M. Vitória L. B. Bentley

2000-01-01

244

Mechanism of Tumor Destruction Following Photodynamic Therapy with Hematoporphyrin Derivative, Chlorin, and Phthalocyanine,  

National Technical Information Service (NTIS)

The effect of photodynamic therapy on the tumor microvasculature in the first few hours after treatment was studied at the light and electron microscopy levels. BALB/c mice with EMT-6 tumor received ip injections of hematoporphyrin derivative, chlorin, or...

J. S. Nelson L. H. Liaw A. Orenstein W. G. Roberts M. W. Berns

1988-01-01

245

Photodynamic Therapy for Granuloma Annulare: More than a Shot in the Dark  

Microsoft Academic Search

Background: Granuloma annulare (GA) is a benign granulomatous and inflammatory skin disorder. The pathogenesis remains enigmatic and convincingly effective treatment options are not available. Inspired by a report showing photodynamic therapy (PDT) to be effective in a single patient with GA, we sought to evaluate this benefit in a series of patients with GA. Observations: PDT was performed in 7

Peter Weisenseel; Alexander Vasilevic Kuznetsov; Sonja Molin; Thomas Ruzicka; Carola Berking; Joerg Christoph Prinz

2008-01-01

246

Cellular and tissue effects induced by photogem® and red LED in photodynamic therapy  

Microsoft Academic Search

In order to consider the photodynamic therapy (PDT) as a clinical treatment for candidosis, it is necessary to know its cytotoxic effect on normal cells and tissues. Therefore, this study evaluated the toxicity of PDT with Photogem® associated with red light-emitting diode (LED) on L929 and MDPC-23 cell cultures and healthy rat palatal mucosa. In the in vitro experiment, the

A. P. D. Ribeiro; A. C. Pavarina; F. Z. Trindade; V. S. Bagnato; C. Kurachi; C. A. de Souza Costa

2011-01-01

247

Monitoring photodynamic therapy of solid tumors online by BOLD-contrast MRI  

Microsoft Academic Search

Antivascular photodynamic therapy (PDT) of tumors with palladium-bacteriopheophorbide (TOOKAD) relies on in situ photosensitization of the circulating drug by local generation of cytotoxic reactive oxygen species, which leads to rapid vascular occlusion, stasis, necrosis and tumor eradication. Intravascular production of reactive oxygen species is associated with photoconsumption of O2 and consequent evolution of paramagnetic deoxyhemoglobin. In this study we evaluate

Shimon Gross; Assaf Gilead; Avigdor Scherz; Michal Neeman; Yoram Salomon

2003-01-01

248

Targeted photodynamic therapy of established soft-tissue infections in mice  

Microsoft Academic Search

The worldwide rise in antibiotic resistance necessitates the development of novel antimicrobial strategies. Although many workers have used photodynamic therapy (PDT) to kill bacteria in vitro, the use of this approach has seldom been reported in vivo in animal models of infection. We have previously described the first use of PDT to treat excisional wound infections by Gram-negative bacteria in

Faten Gad; Touqir Zahra; Tayyaba Hasan; Michael R. Hamblin

2004-01-01

249

Macular translocation surgery with 360-degree peripheral retinectomy following ocular photodynamic therapy of choroidal neovascularization  

Microsoft Academic Search

PurposeTo determine the visual outcomes of eyes that underwent macular translocation surgery with 360 degrees peripheral retinectomy and silicone oil tamponade (MTS360) following ocular photodynamic therapy (OPT) with verteporfin for subfoveal choroidal neovascularization (CNV) associated with age-related macular degeneration (ARMD).

Carl H Park; Cynthia A Toth

2003-01-01

250

Enlightening the impact of immunogenic cell death in photodynamic cancer therapy  

PubMed Central

EMBO J 31 5, 1062–1079 (2012); published online 01172012 In this issue of The EMBO Journal, Garg et al (2012) delineate a signalling pathway that leads to calreticulin (CRT) exposure and ATP release by cancer cells that succumb to photodynamic therapy (PTD), thereby providing fresh insights into the molecular regulation of immunogenic cell death (ICD).

Galluzzi, Lorenzo; Kepp, Oliver; Kroemer, Guido

2012-01-01

251

Aminolaevulinic acid-induced photodynamic therapy: cellular responses to glucose starvation  

PubMed Central

Photodynamic therapy is a cancer treatment based on the interaction of light, oxygen and a photosensitiser. Protoporphyrin. IX is an endogenous photosensitiser derived from the pro-drug aminolaevulinic acid. Tumours contain areas of hypoxia and hypoglycaemia. Tumour cells adapt to these conditions by stress protein induction which may induce resistance to cancer therapies. The effect of chronic hypoglycaemia on sensitivity to aminolaevulinic acid-induced photodynamic therapy in vitro was studied in MCF-7, human breast cancer cells. Following chronic exposure to 0, 1 or 25?mM, glucose, cells were treated with aminolaevulinic acid and the generation of intracellular protoporphyrin. IX measured by spectrofluorimetry. Aminolaevulinic acid-induced photodynamic therapy sensitivity was compared between cells following chronic exposure to 0, 1 or 25?mM glucose. Percentage cell survival was determined by clonogenic assay. Cells cultured in low glucose generated higher levels of protoporphyrin IX compared to standard glucose medium (0?mM glucose: 0.88×10?5?ng?cell?1, 1?mM: 0.86×10?5?ng?cell?1, 25?mM: 0.605×10?5?ng?cell?1, P<0.05). However, photodynamic therapy sensitivity was reduced in glucose deprived cells (0?mM glucose: 61% survival, 1?mM: 80.5% and 25?mM: 39.6%, P<0.05). Chronic exposure to low glucose induces photodynamic therapy resistance despite increased intracellular concentrations of protoporphyrin IX and may reflect cellular adaptation to chronic glucose deprivation. British Journal of Cancer (2002) 86, 1343–1347. DOI: 10.1038/sj/bjc/6600234 www.bjcancer.com © 2002 Cancer Research UK

Wyld, L; Tomlinson, M; Reed, M W R; Brown, N J

2002-01-01

252

Multifunctional hollow mesoporous silica nanocages for cancer cell detection and the combined chemotherapy and photodynamic therapy.  

PubMed

Highly uniform and multifunctional hollow mesoporous silica nanocages that combined excellent properties (good biocompatibility, fluorescence imaging, drug delivery, and dual-mode cancer therapy) in one single system were synthesized. Dye molecules labeled in the nanocages could be used as traceable detectors in fluorescence imaging. A chemotherapeutic drug, doxorubicin (DOX), has been loaded into the nanocages with a high storage capacity due to the large cubic cavities and could be released through the penetrating mesoporous channels in a sustained fashion. Hematoporphyrin molecules were also covalently doped in the nanocages and allowed for photodynamic therapy. More importantly, a cooperative, synergistic therapy combining chemotherapy and photodynamic therapy exhibited high therapeutic efficacy for cancer therapy in vitro. PMID:21604817

Wang, Tingting; Zhang, Lingyu; Su, Zhongmin; Wang, Chungang; Liao, Yi; Fu, Qin

2011-06-10

253

Sonodynamic and photodynamic therapy in advanced breast carcinoma: a report of 3 cases.  

PubMed

Photodynamic therapy (PDT) is an established therapeutic method, first approved by the FDA for certain kinds of cancer in 1998. There are also increasing data to show that a related procedure, sonodynamic therapy (SDT), is a promising new modality for cancer treatment. Here, the authors report clinical results in 3 advanced refractory breast cancer patients who were treated using a combination of sonodynamic and photodynamic therapy (SPDT), along with conventional therapies. All 3 patients had pathologically proven metastatic breast carcinoma. These widely disseminated carcinomas had ultimately failed to respond to conventional therapy. A new sensitizing agent, Sonoflora 1 (SF1) was administered sublingually; then, after a 24-hour delay, patients were treated with a combination of light and ultrasound. All patients had significant partial or complete responses. SPDT is a promising new therapeutic combination for the treatment of breast cancer. PMID:19815599

Wang, Xiaohuai; Zhang, Weimin; Xu, Zhiyong; Luo, Yifan; Mitchell, Doug; Moss, Ralph W

2009-09-01

254

Lasers and photodynamic therapy in the treatment of onychomycosis: a review of the literature.  

PubMed

Onychomycosis is a widespread problem. Oral antifungal medications are currently the gold standard of care, but treatment failure is common and oral therapy is contraindicated in many cases. There is a need for effective treatment without the systemic complications posed by oral therapy. Laser and photodynamic therapy may have the potential to treat onychomycosis locally without adverse systemic effects; some small studies have even reported achieving clinical and mycologic cure. However, there is reason for restraint; these therapies are expensive and time-consuming. Furthermore, they may not be covered by insurance and have not been proven effective with randomized, controlled clinical trials. This paper will review current literature regarding the use of laser and photodynamic therapy as potential treatments for onychomycosis. PMID:24050286

Becker, Caitlin; Bershow, Andrea

2013-09-14

255

Optimization of light dosimetry for photodynamic therapy of Barrett's esophagus  

NASA Astrophysics Data System (ADS)

Background and Objective: Photodynamic therapy (PDT) may be used for ablation of high grade dysplasia and/or early cancer (HGD/T1) in Barrett's esophagus. A complication of PDT is esophageal stricture. The objective of this study was to find the lowest light dose to potentially reduce the incidence of strictures while effectively ablating HGD/T1. Materials and Methods: Patients (n=113) with HGD/T1 received an intravenous injection of porfimer sodium (2 mg/kg). Three days later, laser light (630 nm) was delivered using a cylindrical diffuser inserted in a 20 mm.diameter PDT balloon. Patients were treated at light doses of 115 J/cm, 105 J/cm, 95 J/cm and 85 J/cm. The efficacy was determined by four quadrant biopsies of the treated area three months after PDT. The formation of stricture was determined by the incidence of dysphagia and the need for esophageal dilation. Strictures were considered mild if they required less than 6 dilations, and severe if 6 or more dilations were required. Efficacy and incidence of strictures were tabulated as a function of light dose. Results: Using 115 J/cm, there were 17% of patients with residual HGD/T1 after one treatment. However, when the light doses of 105 J/cm, 95 J/cm and 85 J/cm were used, the residual HGD/T1 after one PDT session was increased to 33%, 30%, and 32% respectively. The overall incidence of strictures (mild and severe) was not correlated to the light dose. However, the incidence of severe strictures was directly proportional to the light dose. Using the light dose of 115 J/cm, 15.3% of patients developed severe strictures compared to about 5% in the groups of patients who received the lower light doses. Conclusions: Decreasing the light dose below 115 J/cm doubled the rate of residual HGD/T1 after one treatment while reducing the incidence of severe strictures to one-third of cases from 115 J/cm. The results may be used to evaluate the risks and benefits of different light doses.

Panjehpour, Masoud; Phan, Mary N.; Overholt, Bergein F.; Haydek, John M.

2004-06-01

256

Multifunctional gold nanoparticles for photodynamic therapy of cancer  

NASA Astrophysics Data System (ADS)

As an important and growing branch of photomedicine, photodynamic therapy (PDT) is being increasingly employed in clinical applications particularly for the treatment of skin cancer. This dissertation focuses on the synthesis, characterization and deployment of gold nanoparticles for enhanced PDT of fibrosarcoma cancer cells. We have developed robust strategies and methods in fabrication of gold nanoparticles with positively- and negatively-tethered surface charges by photo-reduction of gold chloride salt using branched polyethyleneimine and sodium citrate respectively. An optimal concentration window of gold salt has been established to yield the most stable and monodispersed gold nanoparticles. 5-aminolevulinic acid (5-ALA), a photosensitizing precursor, has been successfully conjugated on to positively charged gold nanoparticles through electrostatic interactions. The 5-ALA/gold nanoparticle conjugates are biocompatible and have shown to be preferably taken up by cancer cells. Subsequent light irradiation results in the generation of reactive oxygen species (ROS) in cancer cells, leading to their destruction without adverse effects on normal fibroblasts. We have demonstrated for the first time that gold nanoparticles can enhance PDT efficacy by 50% compared to the treatment with 5-ALA alone. Collected evidence has strongly suggested that this enhancement stems from the elevated formation of ROS via the strongly localized electric field of gold nanoparticles. Through single cell imaging using surface-enhanced Raman scattering enabled by the very same gold nanoparticles, we have shown that multifunctionality of gold nanoparticles can be harvested concurrently for biomedical applications in general and for PDT in specific. In other words, gold nanoparticles can be used not only for targeted drug delivery and field-enhanced ROS formation, but also for monitoring cell destructions during PDT. Finally, our COMSOL Multiphysics simulation of the size-dependent electric field intensity, the measured increase in ROS formation and SERS sensitivity with the particle size all converge to a common origin of the surface plasmon resonance of gold nanoparticles and serve to indicate its beneficial role in field-enhanced processes. By integrating nanotechnology with PDT and with the promising outcome, this research has made a significant contribution in advancing the frontier of photomedicine.

Khaing Oo, Maung Kyaw

257

Atorvastatin reduces functional deficits caused by photodynamic therapy in rats.  

PubMed

Clinical studies have indicated that photodynamic therapy (PDT) significantly prolonged the median survival of patients with gliomas. Experimental studies demonstrate that increasing optical energy and photosensitizer dose leads to increased volume of tumor necrosis. However, increasing the light dose delivered to the tumor may increase the risks of inducing permanent neurological deficits. In the current study, we sought to test the behavioral deficits induced in normal rats by brain PDT and the neurorestorative effects of atorvastatin on PDT-induced behavioral deficits. Considering its potential as a combination treatment of brain tumors, we investigated both in vitro and in vivo whether atorvastatin treatment promotes brain tumor growth. Non-tumored Fischer rats received PDT (n=18). Nine of the PDT-treated animals were treated with atorvastatin. Control animals underwent the same surgical procedure, but did not receive Photofrin and laser light. PDT-treated animals had significant behavioral deficits on days 2, 5, 7, 9 and 14 after PDT, compared with surgery controls. PDT-treated animals receiving atorvastatin displayed significantly ameliorated behavioral deficits on days 7, 9 and 14 after PDT, compared to PDT-treated rats. In vitro tumor cell viability and growth were evaluated. Atorvastatin did not affect the growth of glioma cells. Fischer rats with intracranial 7-day-old 9L glioma tumor cell implantation were randomly subjected to no treatment, PDT alone, atorvastatin alone, or combined treatment with atorvastatin and PDT (6 rats/group). Our data indicate that atorvastatin did not promote tumor growth in either PDT treated and non-treated rats. However, atorvastatin significantly reduced the cell damage caused by PDT. To further test the mechanisms underlying the atorvastatin-mediated reduction of functional deficits, we investigated the effects of atorvastatin on angiogenesis and synaptogenesis. Our data demonstrate that atorvastatin significantly induced angiogenesis and synaptogenesis in the PDT-damaged brain tissue. Our data indicate that PDT induces functional deficits. Atorvastatin treatment promotes functional restoration after PDT, but does not promote glioma growth in vitro and in vivo. Atorvastatin reduces astrocyte and endothelial cell damage caused by PDT and induces angiogenesis and synaptogenesis after PDT. Thus consideration and further testing of the combination of atorvastatin and PDT for the treatment of glioma is warranted. PMID:21850369

Zheng, Xuguang; Chopp, Michael; Lu, Yong; Jiang, James; Zhao, Danping; Ding, Christopher; Yang, Hongyan; Zhang, Li; Jiang, Feng

2011-08-17

258

Phage Therapy and Photodynamic Therapy: Low Environmental Impact Approaches to Inactivate Microorganisms in Fish Farming Plants  

PubMed Central

Owing to the increasing importance of aquaculture to compensate for the progressive worldwide reduction of natural fish and to the fact that several fish farming plants often suffer from heavy financial losses due to the development of infections caused by microbial pathogens, including multidrug resistant bacteria, more environmentally-friendly strategies to control fish infections are urgently needed to make the aquaculture industry more sustainable. The aim of this review is to briefly present the typical fish farming diseases and their threats and discuss the present state of chemotherapy to inactivate microorganisms in fish farming plants as well as to examine the new environmentally friendly approaches to control fish infection namely phage therapy and photodynamic antimicrobial therapy.

Almeida, Adelaide; Cunha, Angela; Gomes, Newton C.M.; Alves, Eliana; Costa, Liliana; Faustino, Maria A.F.

2009-01-01

259

Long-circulating near-infrared fluorescent nanoparticles for diagnosis and photodynamic therapy of cutaneous cancers  

NASA Astrophysics Data System (ADS)

Indocyanine green (ICG) is a near-infrared fluorescence contrast agent, which has enormous potential in early tumor diagnosis and therapy. The objective of this study is to develop biodegradable nanoparticles entrapping ICG and to characterize its intracellular uptake and photodynamic activity in different cancer cell lines. Nanoparticles entrapping ICG were engineered, characterized and the intracellular uptake of ICG was investigated in B16-F10 and C-33A cancer cell lines. The photodynamic activity of ICG-loaded nanoparticles was also investigated. The nanoparticles enhanced the intracellular uptake of ICG and showed significant photodynamic activity, especially at very low ICG concentrations. These preliminary studies indicate the potential of efficient tumor cell delivery and tumoricidal effect of ICG when incorporated in nanoparticles.

Saxena, Vishal; Sadoqi, Mostafa; Kumar, S.; Shao, Jun

2004-07-01

260

Effects of integrin-targeted photodynamic therapy on pancreatic carcinoma cell  

PubMed Central

AIM: To investigate the effects of photodynamic therapy with quantum dots-arginine-glycine-aspartic acid (RGD) probe as photosensitizer on the proliferation and apoptosis of pancreatic carcinoma cells. METHODS: Construction of quantum dots-RGD probe as photosensitizer for integrin-targeted photodynamic therapy was accomplished. After cells were treated with photodynamic therapy (PDT), the proliferation of SW1990 cells were measured by methyl thiazolyl tetrazolium assay. Morphologic changes, cell cycle retardance and apoptosis were observed under fluoroscope and flow cytometry. The expression of myeloid cell leukemia-1 (Mcl-1), protein kinase B (Akt) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) mRNA were detected by reverse transcription-polymerase chain reaction. The amount of reactive oxygen species were also evaluated by fluorescence probe. RESULTS: The photodynamic therapy with quantum dots-RGD probe as photosensitizer significantly inhibited cell proliferation (P < 0.01). Apoptotic cells and morphologic changes could be found under optical microscope. The FCM revealed PDT group had more significant cell apoptosis rate compared to control cells (F = 130.617, P < 0.01) and cell cycle G0/G1 and S retardance (P < 0.05) compared to control cells. The expression of Mcl-1 and Akt mRNA were down-regulated, while expression of TRAIL mRNA was up-regulated after cells treated with PDT. PDT group had more significant number of cells producing reactive oxygen species compared to control cells (F = 3262.559, P < 0.01). CONCLUSION: The photodynamic therapy with quantum dots-RGD probe as photosensitizer significantly inhibits cell proliferation and increases apoptosis in SW1990 cells.

Zhou, Min; Ni, Qian-Wen; Yang, Shan-Ying; Qu, Chun-Ying; Zhao, Peng-Cheng; Zhang, Jian-Cheng; Xu, Lei-Ming

2013-01-01

261

Reduction of thermal damage in photodynamic therapy by laser irradiation techniques  

NASA Astrophysics Data System (ADS)

General application of continuous-wave (CW) laser irradiation modes in photodynamic therapy can cause thermal damage to normal tissues in addition to tumors. A new photodynamic laser therapy system using a pulse irradiation mode was optimized to reduce nonspecific thermal damage. In in vitro tissue specimens, tissue energy deposition rates were measured in three irradiation modes, CW, pulse, and burst-pulse. In addition, methods were tested for reducing variations in laser output and specific wavelength shifts using a thermoelectric cooler and thermistor. The average temperature elevation per 10 J/cm2 was 0.27°C, 0.09°C, and 0.08°C using the three methods, respectively, in pig muscle tissue. Variations in laser output were controlled within ±0.2%, and specific wavelength shift was limited to ±3 nm. Thus, optimization of a photodynamic laser system was achieved using a new pulse irradiation mode and controlled laser output to reduce potential thermal damage during conventional CW-based photodynamic therapy.

Lim, Hyun Soo

2012-12-01

262

Reduction of thermal damage in photodynamic therapy by laser irradiation techniques.  

PubMed

General application of continuous-wave (CW) laser irradiation modes in photodynamic therapy can cause thermal damage to normal tissues in addition to tumors. A new photodynamic laser therapy system using a pulse irradiation mode was optimized to reduce nonspecific thermal damage. In in vitro tissue specimens, tissue energy deposition rates were measured in three irradiation modes, CW, pulse, and burst-pulse. In addition, methods were tested for reducing variations in laser output and specific wavelength shifts using a thermoelectric cooler and thermistor. The average temperature elevation per 10 J/cm2 was 0.27°C, 0.09°C, and 0.08°C using the three methods, respectively, in pig muscle tissue. Variations in laser output were controlled within ± 0.2%, and specific wavelength shift was limited to ± 3 nm. Thus, optimization of a photodynamic laser system was achieved using a new pulse irradiation mode and controlled laser output to reduce potential thermal damage during conventional CW-based photodynamic therapy. PMID:23224063

Lim, Hyun Soo

2012-12-01

263

Preoperative chemoradiotherapy, surgery and adjuvant therapy for resectable pancreatic cancer.  

PubMed

Background/Aims: In order to improve the poor prognosis of pancreatic cancer, a combination therapy consisting of preoperative chemoradiotherapy, surgery and postoperative chemotherapy may be an ideal strategy; nevertheless, the influence of preoperative therapy to postoperative therapy is not investigated. Methodology: Thirty patients with resectable pancreatic ductal adenocarcinoma were enrolled. A 40Gy of radiation (2Gy/day x 20 fractions/4 weeks) was administered together with intravenous infusion of gemcitabine (800mg/m2, days 1, 8 and 15) before surgery. Surgery was performed 3-7 weeks after the final fraction of radiation, and postoperative chemotherapy consisting of 1000mg/m2 gemcitabine (days 1, 8 and 15 every 4 weeks for 6 cycles) was started within 8 weeks after surgery. Results: All 30 patients successfully completed preoperative therapy. Re-staging after such therapy showed radiologically unresectable disease in 4 patients and 1 patient rejected surgery. Among the 25 patients who underwent laparotomy, 21 underwent curative resection. After curative resection, 4 were inadequate in performance status, thus postoperative therapy could not be started. Ten patients completed postoperative adjuvant therapy. Conclusions: The combination therapy for resectable pancreatic cancer seems a feasible and effective approach, though preoperative therapy may reduce the feasibility of postoperative therapy. PMID:23321032

Eguchi, Hidetoshi; Nagano, Hiroaki; Tanemura, Masahiro; Takeda, Yutaka; Marubashi, Shigeru; Kobayashi, Shogo; Kawamoto, Koichi; Wada, Hiroshi; Hama, Naoki; Akita, Hirofumi; Mori, Masaki; Doki, Yuichiro

2013-01-16

264

Advances in adjuvant therapy of gastrointestinal stromal tumors.  

PubMed

The Gastrointestinal Stromal Tumor (GIST) is the most common sarcoma of the gastrointestinal tract. Major prognostic indices in the evaluation and management of GIST include the size, location and tumor mitotic rate. The discovery of the mutation in the tyrosine kinase receptor c-KIT (CD117) revolutionized the treatment of GIST in the early twenty-first century. Since the first case report of the success of the tyrosine kinase inhibitor (TKI) imatinib, in the treatment of a female patient with metastatic GIST, the paradigm of treatment of this tumor has evolved tremendously. The initial use in metastatic GISTs has progressed to use of the TKI in both the adjuvant and neoadjuvant settings. It is now standard of care for patients with complete resection of primary localized GIST, with high risk of recurrence, to have at least one year of adjuvant imatinib. Recent SSGVXIII study shows that patients benefit from extended duration of therapy. PMID:22535506

Adekola, K; Agulnik, M

2012-08-01

265

Comparison of lasers for photodynamic therapy with a phthalocyanine photosensitizer  

Microsoft Academic Search

Three different lasers were compared under the same conditions for their effectiveness at producing photodynamic damage to\\u000a normal colon following sensitization with aluminium sulphonated phthalocyanine (AlSPc). One laser was an argon ion pumped\\u000a continuous wave (CW) dye laser and the other two were pulsed at 10 kHz (copper vapour laser pumped dye laser, and 5 Hz (flashlamp\\u000a pumped dye laser).

H. Barr; P. B. Boulos; A. J. Macrobert; C. J. Tralau; D. Phillips; S. G. Bown

1989-01-01

266

Two-photon photodynamic therapy and its potential application to age related macular degenerations  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) using verteporfin is widely used for treatment of age related macular degeneration (AMD). Due to non-perfect selectivity of the drug accumulation in the neovasculature some collateral damage to healthy tissue arises during the treatment. Damage to healthy structures in the eye is always a concern because of a high probability of reducing visual acuity. Two-photon (2-?) photodynamic therapy potentially offers much higher treatment selectivity than its one-photon (1-?) counterpart. By utilizing focused light for 2-? excitation, treatment volumes on the order of microliters can be achieved thus maximizing localized insult to abnormal blood vessels and sparing healthy tissue. We propose that 2-? photodynamic therapy will be valuable in the treatment of choroidal neovascularization secondary to age related macular degeneration as well as other conditions. To ascertain feasibility of 2-? photodynamic therapy we measured 2-? spectrum and cross sections of verteporfin (80 GM at 940 nm, 1 GM = 10-50 cm4s/photon), chlorin e6 (14 GM at 800 nm) and tetrasulfonated aluminum phthalocyanine (140 GM at 900 nm) and investigated their in vitro efficiency under 2-? excitation. Only verteporfin demonstrated cell kill under the used irradiation parameters (average light intensity 9.1 mW, wavelength 850 nm, total light dose 6900 J/cm2). Dorsal skinfold window chamber model in mouse was used to test efficiency of 2-? PDT with verteporfin in vivo. Although we were able to induce photodynamic damage to a blood vessel using 1-? excitation, 2-? excitation resulted in no visible damage to irradiated blood vessel. The most probable reason is low efficiency of verteporfin as a 2-? photosensitizer. We also report 2-? spectrum of new photosensitizer, HCC4 (4300 GM at 830 nm), specifically designed for efficient 2-? excitation.

Karotki, Aliaksandr; Khurana, Mamta; Bisland, Stuart K.; Moriyama, Eduardo H.; Simpson, E. Rand; Campbell, Melanie C. W.; Collins, Hazel; Anderson, Harry L.; Cramb, David T.; Wilson, Brian C.

2007-02-01

267

Apoptotic induction by photodynamic therapy using hexaminolevulinate with a literature review  

NASA Astrophysics Data System (ADS)

Since the first report by Agarwal et al in 1991 on apoptotic induction by photodynamic therapy (PDT) with chloroaluminium phthalocyanine a large number of papers have come out to show that PDT can induce cell death through apoptosis. This finding may provide potential clinical impact on, for example, those tumor cells resistant to any cancer therapy. The present paper briefly reviews apoptosis with emphasis on PDT-induced apoptosis with hexaminolevulinate.

Furre, Ingegerd E.; Nesland, Jahn M.; Peng, Qian

2009-06-01

268

PEGylated fullerene/iron oxide nanocomposites for photodynamic therapy, targeted drug delivery and MR imaging.  

PubMed

Recently, fullerene and fullerene derivatives owning to their highly enriched physical and chemical properties have been widely explored for applications in many different fields including biomedicine. In this study, iron oxide nanoparticles (IONPs) were decorated onto the surface of fullerene (C60), and then PEGylation was performed to improve the solubility and biocompatibility of C60-IONP, obtaining a multi-functional C60-IONP-PEG nanocomposite with strong superparamagnetism and powerful photodynamic therapy capacity. Hematoporphyrin monomethyl ether (HMME), a new photodynamic anti-cancer drug, was conjugated to C60-IONP-PEG, forming a C60-IONP-PEG/HMME drug delivery system, which demonstrated an excellent magnetic targeting ability in cancer therapy. Compared with free HMME, remarkably enhanced photodynamic cancer cell killing effect using C60-IONP-PEG/HMME was realized not only in a cultured B16-F10 cells in vitro but also in an in vivo murine tumor model due to 23-fold higher HMME uptake of tumor and strong photodynamic activity of C60-IONP-PEG. Moreover, C60-IONP-PEG could be further used as a T2-contrast agent for in vivo magnetic resonance imaging. Our work showed C60-IONP-PEG/HMME had a great potential for cancer theranostic applications. PMID:24034498

Shi, Jinjin; Yu, Xiaoyuan; Wang, Lei; Liu, Yan; Gao, Jun; Zhang, Jing; Ma, Rou; Liu, Ruiyuan; Zhang, Zhenzhong

2013-09-10

269

Role of Adjuvant Chemoradiation Therapy in Adenocarcinomas of the Ampulla of Vater  

Microsoft Academic Search

Purpose: The role of adjuvant chemoradiation therapy (CRT) in the treatment of ampullary cancers remains undefined. We retrospectively compared treatment outcomes in patients treated with pancreaticoduodenectomy alone versus those who received additional adjuvant CRT. Methods and Materials: Between May 1990 and January 2006, 54 of 96 patients with ampullary adenocarcinoma who underwent potentially curative pancreaticoduodenectomy also received adjuvant CRT. The

Sunil Krishnan; Vishal Rana; Douglas B. Evans; Gauri Varadhachary; Prajnan Das; Sumita Bhatia; Marc E. Delclos; Nora A. Janjan; Robert A. Wolff; Christopher H. Crane; Peter W. Pisters

2008-01-01

270

Theranostic probe based on lanthanide-doped nanoparticles for simultaneous in vivo dual-modal imaging and photodynamic therapy.  

PubMed

Dual-modal in vivo tumor imaging and photodynamic therapy using hexagonal NaYF(4):Yb,Er/NaGdF(4) core-shell upconverting nanoparticles combined with a photosensitizer, chlorin e6, is reported. Tumors can be clearly observed not only in the upconversion luminescence image but also in the magnetic resonance image. In vivo photodynamic therapy by systemic administration is demonstrated under 980 nm irradiation. PMID:22915170

Park, Yong Il; Kim, Hyung Min; Kim, Jeong Hyun; Moon, Kyung Chul; Yoo, Byeongjun; Lee, Kang Taek; Lee, Nohyun; Choi, Yoonseok; Park, Wooram; Ling, Daishun; Na, Kun; Moon, Woo Kyung; Choi, Seung Hong; Park, Hong Seok; Yoon, Soo-Young; Suh, Yung Doug; Lee, Sung Ho; Hyeon, Taeghwan

2012-08-23

271

Pharmaceutical development, composition and quantitative analysis of phthalocyanine as the photosensitizer for cancer photodynamic therapy.  

PubMed

Phthalocyanine (Pc) and its related derivatives are a class of functional materials that are easily activated by the light at a special wavelength. As such photosensitizer, Pc has been applied to photodynamic therapy (PDT), in addition to its broad applications in many fields, for both malignant and benign diseases. One of our long-term research focuses is to develop Pc for cancer therapy. Herein we briefly review mechanisms of action of Pc used for photodynamic therapy, its pharmaceutical development and molecular modification to enhance its drugability and improve its intracellular localization. We also describe the current status of the Pc derivatives under clinical investigation, and analyze the methods used for quantitative analysis of those Pc derivatives. PMID:23746989

Jiang, Zhou; Shao, Jingwei; Yang, Tingting; Wang, Jian; Jia, Lee

2013-05-18

272

Luminescence/magnetic resonance imaging and photodynamic therapy based on upconverting nanoparticles  

NASA Astrophysics Data System (ADS)

The luminescence and magnetic resonance imaging (MRI) and photodynamic therapy (PDT) using lanthanide-doped upconverting nanoparticles (UCNPs) is reported. With the aim to induce a therapeutic effect, a photosensitizer, chlorin e6 (Ce6), was conjugated to UCNPs. Owing to the enhanced permeability and retention effect, UCNPs combined with a photosensitizer, chlorin e6 (UCNP-Ce6) could be readily accumulated at the tumors, which could be clearly observed not only in the upconversion luminescence image but also in the MRI image. Using the energy transfer from UCNPs to Ce6, cytotoxic singlet oxygen could be generated. An in vivo PDT effect by systemic administration of UCNP-Ce6 was demonstrated under 980-nm irradiation. These results indicate that UCNP-Ce6 can be used not only as dual-modal imaging probes for accurate diagnosis but also as photodynamic therapy agent for efficient therapy.

Park, Yong Il; Kim, Hyung Min; Kim, Jeong Hyun; Moon, Kyung Chul; Yoo, Byeongjun; Lee, Kang Taek; Yoon, Soo-Young; Suh, Yung Doug; Lee, Sung Ho; Hyeon, Taeghwan

2012-10-01

273

Genomic subtypes in choosing adjuvant therapy for breast cancer.  

PubMed

The use of gene expression profiling has impacted our understanding of breast cancer biology and increasingly has played a role in guiding clinical decisions. We have used hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status for years to guide selection of therapy. More recently, gene expression analysis has facilitated the identification of at least five intrinsic subtypes of breast cancer. Potential therapeutic targets have also been identified using genomic profiling. Several tests, such as the 21-gene recurrence score assay (Oncotype DX) and the 70-gene prognosis signature (MammaPrint), have been well validated as prognostic tools for early-stage breast cancer, and have aided in adjuvant therapy decisions for early-stage, HR-positive breast cancer patients. Genomic profiling has the potential to provide additional insight into drug discovery and clinical trial design by identifying appropriate targeted therapies for subtypes of breast cancer. PMID:23687790

Zelnak, Amelia B; O'Regan, Ruth M

2013-03-01

274

Racial and Ethnic Differences in Adjuvant Hormonal Therapy Use  

PubMed Central

Abstract Background In the United States, 5-year breast cancer survival is highest among Asian American women, followed by non-Hispanic white, Hispanic, and African American women. Breast cancer treatment disparities may play a role. We examined racial/ethnic differences in adjuvant hormonal therapy use among women aged 18–64 years, diagnosed with hormone receptor-positive breast cancer, using data collected by the Northern California Breast Cancer Family Registry (NC-BCFR), and explored changes in use over time. Methods Odds ratios (OR) comparing self-reported ever-use by race/ethnicity (African American, Hispanic, non-Hispanic white vs. Asian American) were estimated using multivariable adjusted logistic regression. Analyses were stratified by recruitment phase (phase I, diagnosed January 1995–September 1998, phase II, diagnosed October 1998–April 2003) and genetic susceptibility, as cases with increased genetic susceptibility were oversampled. Results Among 1385 women (731 phase I, 654 phase II), no significant racial/ethnic differences in use were observed among phase I or phase II cases. However, among phase I cases with no susceptibility indicators, African American and non-Hispanic white women were less likely than Asian American women to use hormonal therapy (OR 0.20, 95% confidence interval [CI]0.06–0.60; OR 0.40, CI 0.17–0.94, respectively). No racial/ethnic differences in use were observed among women with 1+ susceptibility indicators from either recruitment phase. Conclusions Racial/ethnic differences in adjuvant hormonal therapy use were limited to earlier diagnosis years (phase I) and were attenuated over time. Findings should be confirmed in other populations but indicate that in this population, treatment disparities between African American and Asian American women narrowed over time as adjuvant hormonal treatments became more commonly prescribed.

Li, Christopher; John, Esther M.; Terry, Mary Beth; Daly, Mary; Buys, Saundra S.; Habel, Laurel; Thompson, Beti; Yanez, N. David; Coronado, Gloria D.

2012-01-01

275

Real-time monitoring of singlet oxygen in photodynamic therapy with chemiluminescence  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is a cancer therapy most of which using light excites sensitizer mainly to produce singlet oxygen (1O2) to kill tumor cells by oxidation reaction. Monitoring the singlet oxygen production is an important task for getting more useful dosage information in photodynamic therapy to enhance the effect. In order to monitor singlet oxygen in PDT, the Chemiluminescence (CL) probe, which could react with singlet oxygen and emit photons, was selected and employed on mice to produce CL. The CL was collected and recorded by a single photon detection system in real time. The results showed that the signal intensity was high and indicated that the chemiluminescence could measure singlet oxygen in vivo sensitively. And during photodynamic therapy the CL signal dropped gradually. Different therapy dosages had different decay life. Any of the decay had two different parts: the rapid component and the slow component. During PDT, reactive oxygen would oxidize biomolecules of tissue, and oxygen was consumed. It would cause a rapid component; by combining with chemiluminescence and fluorescence detection technique, the first-order elimination coefficient of tissue was proved to be degressive during PDT. We deduced that the damaged vascular in PDT would provide littler oxygen and tissue hypoxia was more severely. It may quicken CL decay and caused the slow component. In conclusion, the results proved that monitoring 1O2 by CL could give useful information not only to evaluate the effect of PDT but also to judge the tissue oxygen depletion.

Wei, Yan Chun; Yang, Li Yong; Song, Jia Xing

2008-12-01

276

Photodynamic therapy and the treatment of neoplastic diseases of the larynx  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is an innovative treatment involving the use of light-sensitive drugs to selectively identify and destroy diseased cells. Therefore, photodynamic therapy has the potential to treat and cure precancerous and early cancerous lesions (carcinoma in situ (CIS), T1 and T2) of the larynx while preserving normal tissue. Twenty-four patients with recurrent leukoplakia and carcinomas of the larynx were treated with PDT with follow-up to 60 months. Fourteen patients with T1 squamous cell carcinomas of the vocal cord, 2 patients with a T2 squamous cell carcinoma of the vocal cord failing radiotherapy, and 6 patients with CIS and sever atypia were treated with PDT and obtained a complete response and are disease free. One patient with a T3 carcinoma of the larynx was treated with PDT but died 5 weeks post-treatment of unrelated causes and could not be assessed. Photodynamic therapy is a promising therapy for treatment of precancerous and cancerous lesions of the larynx. This therapy may be particularly beneficial for the treatment of recurrent carcinomas of the larynx that have failed conventional radiotherapy, thereby preserving voice and eliminating the need for destructive laryngeal surgery.

Biel, Merrill A.

1995-05-01

277

Adjuvants.  

PubMed

In summary, HIV vaccine studies described have generally not been designed to measure the effect of the adjuvant or to make comparisons between adjuvants. In only one study was a head-to-head comparison made between HIV antigen alone and antigen formulated with different adjuvants. We hope that future experiments with HIV/SIV vaccine candidates will be designed to determine the relative potency and safety of different adjuvants. Unfortunately, such experiments tend to be tedious and expensive. The design of these studies will need to address a number of variables which influence the response to the vaccine, including route and schedule of immunization, genotype and species of the vaccinated subject, and intrinsic characteristics of the antigen. In addition, the immunologic endpoints should include measurement of both B and T cell function. The carrier/adjuvant/antigen formulation should be hand-tailored and then standardized so that it is manufactured reproducibly without producing different biological effects between lots, and the vaccine formulation should be stable on storage and shipping. Finally, we obviously need to identify and test the protective antigen or antigens. The best adjuvant will never correct the choice of the wrong epitope. PMID:2132879

Edelman, R; Tacket, C O

1990-01-01

278

Physiotherapy as an adjuvant therapy for treatment of TMJ disorders.  

PubMed

Physiotherapy has long been used to cure joint and muscle diseases. It has also been used to treat various diseases without inflicting mental trauma or the pain of surgery. This adjunctive therapeutic modality is widely used for patients with orofacial disorders, especially in the prevention or treatment of temporomandibular joint (TMJ) disorder, hypomobility, or ankylosis. Physiotherapy has a particular importance in the treatment of TMJ disorders such as myofascial pain and internal derangement. This review article highlights the importance of physiotherapy as an emerging adjuvant therapy in the treatment of TMJ disorders. PMID:22414516

Aggarwal, Anshul; Keluskar, Vaishali

279

Adjuvant Therapy in Renal Cell Carcinoma--Past, Present, and Future?  

PubMed Central

To date, no effective adjuvant treatment for renal cell carcinoma (RCC) has been described, but research in this area is important since the 5-year relapse rate for intermediate- and high-risk early-stage RCC is 30%–40%. Metastatic RCC can be treated successfully with immune therapy and targeted therapy. Adjuvant trials with immune therapy have been conducted, but they reported no benefit in disease-free survival, and clinical trials with targeted agents have not yet reported results. Further advances in our understanding of the molecular pathogenesis of RCC will identify additional potential targets for adjuvant treatment trials. Future challenges will consequently include target identification, as well as trial design to answer multiple trial questions concurrently, comprehensively, and economically. We review the past efforts, summarize the current adjuvant clinical trial landscape, and consider the challenges in adjuvant trials for RCC. Additionally, we identify potential future adjuvant trial treatments and propose an alternative design for future adjuvant clinical trials.

Janowitz, Tobias; Welsh, Sarah J.; Zaki, Kamarul; Mulders, Peter; Eisen, Tim

2013-01-01

280

Photodynamic laser therapy for rheumatoid arthritis. Cell culture studies and animal experiments.  

PubMed

The introduction of arthroscopic techniques has improved the surgical therapy of rheumatoid arthritis. The additional application of the holmium:yttrium aluminum garnet (Ho:YAG) laser likewise holds great promise by providing complete hemorrhagic control. Unfortunately, a minimally invasive solution for use in smaller joints has not yet emerged. The present study describes the possible treatment of these joints by means of photodynamic laser therapy. Cell culture studies with human synovial fibroblasts obtained from patients with rheumatoid arthritis have demonstrated a cytotoxic effect after administration of Photosan-3 as a photosensitizer and subsequent laser irradiation at 630 nm. for the in vivo studies, IgG-induced arthritis in rabbits, which is histologically consistent with the proliferative phase of rheumatoid arthritis, was used as the animal model. The histologic picture following photodynamic laser therapy with Photosan-3 revealed complete synovial destruction which also extended to the border of the subjacent joint capsule. In contrast, bradytrophic structures, e.g. cartilage. menisci, and ligaments, remained unchanged at both the macroscopic and microscopic levels. Therefore, photodynamic laser therapy can be considered a new method in the surgical treatment of inflammatory disease of the synovial membrane. It has the advantage of being minimally invasive, while offering a high degree of efficacy and selectivity. PMID:9127856

Hendrich, C; Hüttmann, G; Lehnert, C; Diddens, H; Siebert, W E

1997-01-01

281

Studying Light Propagation in Bone for Treatment of Bone Cancers with Photodynamic Therapy  

NASA Astrophysics Data System (ADS)

Photodynamic therapy makes use of light, photosensitizing agents, and oxygen as a selective means of treating cancer. The work presented is aimed at applying photodynamic therapy towards treatment of osteosarcoma in small animal clinics. To best facilitate clinical treatments, we must first understand how light propagates and how best to deliver adequate light to achieve phototoxic effects within bone. This work aims at characterizing how light propagates through bone and then applying that knowledge towards predicting light distributions in bone. Reflectance spectroscopy using an optical fiber source-collector pair is used to determine the scattering properties of bone tissues, and the absorption due to water and oxygenated and deoxygenated hemoglobin---native absorbers at visible and near-IR wavelengths. Resulting optical characterizations are then applied to a cylindrically symmetric Monte Carlo model in order to predict and guide the delivery of light within bone in order to achieve the desired phototoxic effect.

Rossi, Vincent; Gustafson, Scott; Jacques, Steven

2008-05-01

282

Photodynamic therapy for high-grade dysplasia of bile duct via a choledochoscope.  

PubMed

When a distal common bile duct neoplasm is at the stage of carcinoma in situ or high-grade dysplasia, it is difficult for the surgeon to decide whether to perform pancreaticoduodenectomy. Here we describe a patient with a progressive dysplastic lesion in the common bile duct, which developed from moderate-high to high-grade dysplasia in approximately 2 mo. The patient refused major surgery. Therefore, endoscopic-assisted photodynamic therapy was performed. The result at follow-up using a trans-T-tube choledochoscope showed that the lesion was completely necrotic. This report is the first to describe the successful treatment of high-grade dysplasia of the distal bile duct using photodynamic therapy via a choledochoscope. PMID:24023506

Zhou, Jiang-Jiao; Xiong, Li; Li, Qing-Long; Gu, Ying; Wen, Yu; Deng, Xiao-Feng; Miao, Xiong-Ying

2013-09-01

283

Photodynamic Therapy for Cancer and for Infections: What Is the Difference?  

PubMed Central

Photodynamic therapy (PDT) was discovered over one hundred years ago when it was observed that certain dyes could kill microorganisms when exposed to light in the presence of oxygen. Since those early days, PDT has mainly been developed as a cancer therapy and as a way to destroy proliferating blood vessels. However, recently it has become apparent that PDT may also be used as an effective antimicrobial modality and a potential treatment for localized infections. This review discusses the similarities and differences between the application of PDT for the treatment of microbial infections and for cancer lesions. Type I and type II photodynamic processes are described, and the structure-function relationships of optimal anticancer and antimicrobial photosensitizers are outlined. The different targeting strategies, intracellular photosensitizer localization, and pharmacokinetic properties of photosensitizers required for these two different PDT applications are compared and contrasted. Finally, the ability of PDT to stimulate an adaptive or innate immune response against pathogens and tumors is also covered.

Sharma, Sulbha K.; Mroz, Pawel; Dai, Tianhong; Huang, Ying-Ying; St. Denis, Tyler G.; Hamblin, Michael R.

2012-01-01

284

Photodynamic therapy of malignancy of skin with He-Ne laser  

NASA Astrophysics Data System (ADS)

Objective: Research on the photodynamic therapy of malignancy of skin with He-Ne Laser. Methods: 35 cases of skin malignancy were treated with photodynamic therapy. He-Ne laser with output power of 600 mW was used and hematoporphyrin derivative (HPD) was applied, at a dose of 5mg/kg of body. 15 patients received simple surface irradiation, 20 patients received both surface and insertion irradiation. 28 patients underwent treatment for one time, 7 patients twice. The 12 cases were basel cell carcinoma, 7 cases were squamous cell carcinoma, 4 cases were skin carcinoma in situ, 8 cases were skin Paget's disease, 1 case was Paget's disease accompanying adenoid carcinoma, 1 case malignant melanoma, 1 case red hypertrophic disease, 1 case recurrent perianal carcinoma deriving from rectum.

Zhu, Jing; Shi, Hongmin; Zhang, Hui-Guo

2005-07-01

285

Photodynamic therapy of feline superficial squamous cell carcinoma using topical 5-aminolaevulinic acid.  

PubMed

A study was undertaken to investigate the treatment of superficial squamous cell carcinoma of the nasal planum, pinna and eyelid in cats by photodynamic therapy, using topical 5-aminolaevulinic acid cream, with subsequent exposure to red light of wavelength 635 nm, supplied by a light-emitting diode source. A total of 13 squamous cell carcinomas were treated, including 10 nasal planum lesions, two pinnal lesions and one eyelid lesion. After a single treatment, complete responses were seen in nine out of 10 nasal planum lesions, one out of two pinnal lesions and the eyelid lesion. The overall complete response rate for lesions managed with a single photodynamic therapy treatment was 85 per cent. Seven of the 11 lesions (63.6 per cent) showing a complete response subsequently recurred; the time to recurrence ranged from 19 to 56 weeks (median 21 weeks, mean 26.7 weeks). PMID:11327662

Stell, A J; Dobson, J M; Langmack, K

2001-04-01

286

Two-photon photodynamic therapy by water-soluble self-assembled conjugated porphyrins.  

PubMed

Studies on two-photon absorption (2PA) photodynamic therapy (PDT) by using three water-soluble porphyrin self-assemblies consisting of ethynylene-linked conjugated bis (imidazolylporphyrin) are reviewed. 2PA cross-section values in water were obtained by an open aperture Z-scan measurement, and values were extremely large compared with those of monomeric porphyrins such as hematoporphyrin. These compounds were found to generate singlet oxygen efficiently upon one- as well as two-photon absorption as demonstrated by the time-resolved luminescence measurement at the characteristic band of singlet oxygen at 1270 nm and by using its scavenger. Photocytotoxicities for HeLa cancer cells were examined and found to be as high as those of hematoporphyrin, demonstrating that these compounds are potential candidates for 2PA-photodynamic therapy agents. PMID:23484074

Ogawa, Kazuya; Kobuke, Yoshiaki

2012-12-27

287

Two-Photon Photodynamic Therapy by Water-Soluble Self-Assembled Conjugated Porphyrins  

PubMed Central

Studies on two-photon absorption (2PA) photodynamic therapy (PDT) by using three water-soluble porphyrin self-assemblies consisting of ethynylene-linked conjugated bis (imidazolylporphyrin) are reviewed. 2PA cross-section values in water were obtained by an open aperture Z-scan measurement, and values were extremely large compared with those of monomeric porphyrins such as hematoporphyrin. These compounds were found to generate singlet oxygen efficiently upon one- as well as two-photon absorption as demonstrated by the time-resolved luminescence measurement at the characteristic band of singlet oxygen at 1270 nm and by using its scavenger. Photocytotoxicities for HeLa cancer cells were examined and found to be as high as those of hematoporphyrin, demonstrating that these compounds are potential candidates for 2PA-photodynamic therapy agents.

Ogawa, Kazuya; Kobuke, Yoshiaki

2013-01-01

288

Adjuvant radiation therapy in metastatic lymph nodes from melanoma  

PubMed Central

Purpose To analyze the outcome after adjuvant radiation therapy with standard fractionation regimen in metastatic lymph nodes (LN) from cutaneous melanoma. Patients and methods 86 successive patients (57 men) were treated for locally advanced melanoma in our institution. 60 patients (69%) underwent LN dissection followed by radiation therapy (RT), while 26 patients (31%) had no radiotherapy. Results The median number of resected LN was 12 (1 to 36) with 2 metastases (1 to 28). Median survival after the first relapse was 31.8 months. Extracapsular extension was a significant prognostic factor for regional control (p = 0.019). Median total dose was 50 Gy (30 to 70 Gy). A standard fractionation regimen was used (2 Gy/fraction). Median number of fractions was 25 (10 to 44 fractions). Patients were treated with five fractions/week. Patients with extracapsular extension treated with surgery followed by RT (total dose ?50 Gy) had a better regional control than patients treated by surgery followed by RT with a total dose <50 Gy (80% vs. 35% at 5-year follow-up; p = 0.004). Conclusion Adjuvant radiotherapy was able to increase regional control in targeted sub-population (LN with extracapsular extension).

2011-01-01

289

Analysis of Potential Radiosensitizing Materials for X-Ray-Induced Photodynamic Therapy  

Microsoft Academic Search

For a development of deep tumor treatment in photodynamic therapy, a feasibility of novel radiosensitizers induced by x-ray\\u000a was investigated. The sensitizers are designed to generate reactive oxygen species (ROS) inside or outside the cell, possibly\\u000a leading to damage exclusively on tumor cells and reservation of normal cells along the x-ray path. Taking note of the similarity\\u000a in energy transfer

Junko Takahashi; Masaki Misawa

2007-01-01

290

Photodynamic Therapy of B16F10 Murine Melanoma with Lutetium Texaphyrin  

Microsoft Academic Search

Photodynamic therapy (PDT) of pigmented melanoma has generally been unsuccessful because of insufficient light penetration in such tissues. In this study, the responsiveness of the heavily pigmented B16F10 murine melanoma to lutetium texaphyrin (PCI-0123), a water-soluble sensitizer with strong absorbance in the near infrared (700–760 nm), was examined. These studies were carried out in both normal and ApoE deficient C57BL\\/6

Kathryn W. Woodburn; Qing Fan; David Kessel; Yu Luo; Stuart W. Young

1998-01-01

291

Zinc phthalocyanine-loaded PLGA biodegradable nanoparticles for photodynamic therapy in tumor-bearing mice  

Microsoft Academic Search

Nanoparticles formulated from the biodegradable copolymer poly(lactic-coglycolic acid) (PLGA) were investigated as a drug\\u000a delivery system to enhance tissue uptake, permeation, and targeting of zinc(II) phthalocyanine (ZnPc) for photodynamic therapy.\\u000a Three ZnPc nanoparticle formulations were prepared using a solvent emulsion evaporation method and the influence of sonication\\u000a time on nanoparticle shape, encapsulation and size distribution, in vitro release, and in

Maha Fadel; Kawser Kassab; Doa Abdel Fadeel

2010-01-01

292

A new treatment regimen in combined intravitreal injection of triamcinolone acetonide and photodynamic therapy  

Microsoft Academic Search

Background  Combined photodynamic therapy (PDT) and intravitreal injection of triamcinolone acetonide is a new option in the treatment of the neovascular form of age-related macular degeneration. With the aim of increasing safety and efficacy we examined whether it is possible to administer the intravitreal injection prior to PDT.Methods  Patients with retinal angiomatous proliferation, who have an unfavourable prognosis when treated with PDT

Ilse Krebs; Susanne Binder; Ulrike Stolba

2006-01-01

293

Photodynamic Therapy of the Canine Prostate: Intra-arterial Drug Delivery  

Microsoft Academic Search

Purpose. Interstitial photodynamic therapy (PDT) selectively destroys tissue targeted with a photosensitizer and then exposed to light of a specific wavelength. We report a novel delivery method-intra-arterial drug delivery for PDT of the prostate-in a canine model.Methods. To evaluate drug distribution, the prostatovesical artery was selectively cannulated and photosensitizers alone or in conjunction with 99m-technetium-labeled macro-aggregated albumin ({sup 99m}Tc-MAA) were

Ronald B. Moore; Zhengwen Xiao; Richard J. Owen; Robert Ashforth; Dwayne Dickey; Cathy Helps; John Tulip

2008-01-01

294

Self-quenchable biofunctional nanoparticles of heparin–folate-photosensitizer conjugates for photodynamic therapy  

Microsoft Academic Search

Novel amphiphilic polysaccharide\\/PS conjugates synthesized by chemical conjugation of heparin with a hydrophobic photosensitizer (PS), pheophorbide a (PhA), and a targeting ligand, folate, were investigated for their potential application in photodynamic therapy (PDT). The anticoagulant activity of heparin-PhA (HP) and folate–heparin–PhA (FHP) conjugates was significantly decreased compared to that of heparin, thereby potentially reducing the hemorrhagic side effects. The critical

Li Li; Byoung-chan Bae; Thanh Huyen Tran; Kwon Hyeok Yoon; Kun Na; Kang Moo Huh

2011-01-01

295

Antimicrobial effect of photodynamic therapy using a highly pure chlorin e6  

Microsoft Academic Search

The aim of the present study is to evaluate the antimicrobial effect of photodynamic therapy (PDT) using a highly pure chlorin\\u000a e6 (Ce6), against various pathogenic bacteria. To examine the antimicrobial effect of Ce6-mediated PDT against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Salmonella enterica serovar Typhimurium, inhibition zone formation, CFU quantification, and bacterial viability were evaluated. Inhibition zone\\u000a analysis

Jong-Hwan Park; Yeon-Hee Moon; Iel-Soo Bang; Yong-Chul Kim; Soo-A Kim; Sang-Gun Ahn; Jung-Hoon Yoon

2010-01-01

296

Robot-assisted light dose evaluation for endoscopically guided photodynamic therapy: A preliminary study  

Microsoft Academic Search

Conventional endoscope-guided photodynamic therapy (PDT) suffers mostly from motion artifacts, therefore expert hand-eye coordination was always needed during manual operations. In this paper we introduced a visual servo scheme to handle the tracking problem between the focused area and the targeted lesions. The scheme is consisted of real-time feature matching, relative motion cancellation and real-time light dose surveillance. Experiments were

Dongwen Zhang; Lei Wang; Jia Gu; Zhen Zheng

2009-01-01

297

Photodynamic therapy-induced death of HCT 116 cells: Apoptosis with or without Bax expression  

Microsoft Academic Search

Cell death following photodynamic therapy (PDT) with the photosensitizer Pc 4 involves the intrinsic pathway of apoptosis.\\u000a To evaluate the importance of Bax in apoptosis after PDT, we compared the PDT responses of Bax-proficient (Bax+\\/?) and Bax knock-out (BaxKO) HCT116 human colon cancer cells. PDT induced a slow apoptotic process in HCT Bax+\\/? cells following a long delay in the

S.-M. Chiu; L.-Y. Xue; K. Azizuddin; N. L. Oleinick

2005-01-01

298

Polyion complex micelles entrapping cationic dendrimer porphyrin: effective photosensitizer for photodynamic therapy of cancer  

Microsoft Academic Search

Photosensitizers play a crucial role in the photodynamic therapy (PDT) of cancer. In this study, a third-generation aryl ether dendrimer porphyrin with 32 primary amine groups on the periphery, [NH2CH2CH2NHCO]32DPZn, and pH-sensitive, polyion complex micelles (PIC) composed of the porphyrin dendrimer and PEG-b-poly(aspartic acid), were evaluated as new photosensitizers (PSs) for PDT in the Lewis Lung Carcinoma (LLC) cell line.

Guo-Dong Zhang; Atsushi Harada; Nobuhiro Nishiyama; Dong-Lin Jiang; Hiroyuki Koyama; Takuzo Aida; Kazunori Kataoka

2003-01-01

299

Differential vascular response and relationship to tumor response with photodynamic therapy using WST09 (TOOKAD)  

Microsoft Academic Search

Bacteriopheophorbide molecules are second-generation photosensitizers with promise for PHotodynamic Therapy applications due largely to their absorption peaks in the near-Infrared region. Palladium bcteriopheophorbide, also called TOOKAD, has been successfully evaluated in several pre-clinical animal models. In this study the effect on tumor and normal vasculature was evaluated using an intravital vascular model on mouse cremaster muscle implanted with the RIF

Greta M. Garbo; Peter K. Kik; Linda T. Harrison; Pierre H. Brun; Dominique Blanc; Pamela S. Paulin; Thomas J. Wieman; Victor H. Fingar

2004-01-01

300

Combined hyperthermia and chlorophyll-based photodynamic therapy: tumour growth and metabolic microenvironment  

Microsoft Academic Search

The effects of combined and simultaneously applied localised 43°C hyperthermia (HT) and an antivascular bacteriochlorophyll-serine-based photodynamic therapy (Bchl-ser-PDT) on tumour growth and several microenvironmental parameters were examined. Rats bearing DS-sarcomas were allocated to treatment groups: (i) sham-treatment (control), (ii) Bchl-ser-PDT (20 mg kg?1 i.v.), (iii) localised HT, (iv) Bchl-ser-PDT+HT. The light source used was an infrared-A irradiator, which, by use

D K Kelleher; O Thews; A Scherz; Y Salomon; P Vaupel

2003-01-01

301

Photochemical destruction of the Bcl2 oncoprotein during photodynamic therapy with the phthalocyanine photosensitizer Pc 4  

Microsoft Academic Search

Photodynamic therapy (PDT), utilizing a photosensitizer and visible light, causes localized oxidative damage. With the mitochondrial photosensitizer Pc 4, PDT induces apoptosis, yet its molecular targets are not known. Here, the anti-apoptotic protein Bcl-2 is shown to be highly sensitive to PDT, as judged on Western blots by the disappearance of anti-Bcl-2-reactive material from the position of the native 26

Liang-yan Xue; Song-mao Chiu; Nancy L Oleinick

2001-01-01

302

Transitions of multifocal electroretinography following combined intravitreal bevacizumab and photodynamic therapy for polypoidal choroidal vasculopathy  

Microsoft Academic Search

To investigate the changes in the multifocal electroretinography (ERG) after combined intravitreal bevacizumab and photodynamic\\u000a therapy (PDT) for polypoidal choroidal vasculopathy (PCV) patients. Thirteen eyes of 13 patients were included in the study.\\u000a The latencies and average response densities of all the six ring retinal regions were measured and compared before treatment\\u000a and 1, 3, and 6 months after treatment. The

Chengguo Zuo; Feng Wen; Jiaqing Li; Yan Liu; Meng Li

2009-01-01

303

Laser light application and light monitoring for photodynamic therapy in hollow organs  

Microsoft Academic Search

Photodynamic therapy (PDT) of tumours in hollow organs requires light application devices which enable homogeneous illumination\\u000a of the tissue surface in hollow organs. This paper presents two laser light application systems generating a homogeneous light\\u000a distribution and one monitoring unit which detects variations in the applied laser light intensity during treatment.\\u000a \\u000a A cylindrical light diffuser has been developed for PDT

R. Sroka; M. Krug; A. Noack; E. Unsöld; C. Ell

1993-01-01

304

Bactericidal effects of different laser wavelengths on periodontopathic germs in photodynamic therapy  

Microsoft Academic Search

This study was an attempt to clarify whether the bactericidal effects of photodynamic therapy (PDT) are wavelength or dose-dependent.\\u000a We also attempted to create an optimised protocol for a light-based bactericidal modality to eliminate periodontal pathogens.\\u000a Cultures of Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Porphromonas gingivalis, Prevotella intermedia, and Streptococcus sanguis, were exposed to a He-Ne laser (632.8 nm) with a 30

You Chan; Chern-Hsiung Lai

2003-01-01

305

Single continuous wave laser induced photodynamic/plasmonic photothermal therapy using photosensitizer-functionalized gold nanostars.  

PubMed

Chlorin e6 conjugated gold nanostars (GNS-PEG-Ce6) are used to perform simultaneous photodynamic/plasmonic photothermal therapy (PDT/PPTT) upon single laser irradiation. The early-phase PDT effect is coordinated with the late-phase PPTT effect to obtain synergistic anticancer efficiency. The prepared GNS-PEG-Ce6 shows excellent water dispersibility, good biocompatibility, enhanced cellular uptake and remarkable anticancer efficiency upon irradiation in vivo. PMID:23404693

Wang, Shouju; Huang, Peng; Nie, Liming; Xing, Ruijun; Liu, Dingbin; Wang, Zhe; Lin, Jing; Chen, Shouhui; Niu, Gang; Lu, Guangming; Chen, Xiaoyuan

2013-02-13

306

Cellular and tissue effects induced by photogem® and red LED in photodynamic therapy  

Microsoft Academic Search

In order to consider the photodynamic therapy (PDT) as a clinical treatment for candidosis, it is necessary to know its cytotoxic\\u000a effect on normal cells and tissues. Therefore, this study evaluated the toxicity of PDT with Photogem® associated with red\\u000a light-emitting diode (LED) on L929 and MDPC-23 cell cultures and healthy rat palatal mucosa. In the in vitro experiment, the

A. P. D. Ribeiro; A. C. Pavarina; F. Z. Trindade; V. S. Bagnato; C. Kurachi; C. A. de Souza Costa

2011-01-01

307

Dose-related structural effects of photodynamic therapy on choroidal and retinal structures of human eyes  

Microsoft Academic Search

Purpose. To determine the effects of photodynamic therapy (PDT) on choroidal and retinal structures of human eyes. Methods. One eye from each of three patients with large malignant melanomas of the uvea destined for enucleation received PDT using verteporfin according to the approved treatment recommendations for patients with age-related macular degeneration. Two laser spots and two light doses (50 J\\/cm2

Ursula Schlötzer-Schrehardt; Arne Viestenz; Gottfried O. H. Naumann; Horst Laqua; S. Michels; Ursula Schmidt-Erfurth

2002-01-01

308

Adjuvant Therapy of Pancreatic Cancer. Highlights from the "2011 ASCO Annual Meeting". Chicago, IL, USA; June 3-7, 2011.  

PubMed

Strong evidence exists for the use of adjuvant chemotherapy following surgical resection in pancreatic cancer, whereas the role of adjuvant chemoradiotherapy remains controversial. The optimal time to initiate adjuvant therapy has yet to be elucidated, but is usually started 2-10 weeks following resection. First line adjuvant chemotherapy is gemcitabine, as this drug has demonstrated the better efficacy in studies. Other chemotherapeutic agents and gemcitabine in combination with biologic agents are under investigation. Furthermore, predicting response to gemcitabine based chemotherapy and other adjuvant therapies will be invaluable in guiding the practitioner to choose the most appropriate adjuvant treatment. Once adjuvant therapy has been started, accurately quantifying response to therapy is also important. The adjuvant regimen may be appropriately modified if response is inadequate. This review is an update from the 2011 American Society of Clinical Oncology (ASCO) Annual Meeting regarding recent developments in the adjuvant treatment of pancreatic cancer with regards to choice of adjuvant regimen, timing of adjuvant therapy, predicting response to therapy and measuring response to adjuvant therapy. We will present the findings from Abstracts #4039, #4042, #e14519, #4118, and #4024. In conclusion, multiple adjuvant therapeutic regimens are associated with incremental improvements in the management of pancreatic cancer. The timing of initiation of adjuvant therapy appears to be important in outcomes. Research is ongoing into markers that can predict response to adjuvant therapy. PMID:21737892

Sharma, Charu; Horowitz, David; Chabot, John; Saif, Muhammad Wasif

2011-07-08

309

Gold nanorods as dual photo-sensitizing and imaging agents for two-photon photodynamic therapy.  

PubMed

Gold nanorods with three different aspect ratios were prepared and their dual capabilities for two-photon imaging and two-photon photodynamic therapy have been demonstrated. These gold nanorods exhibit large two-photon absorption action cross-sections, about two orders of magnitude larger than small organic molecules, which makes them suitable for two-photon imaging. They can also effectively generate singlet oxygen under two-photon excitation, significantly higher than traditional photosensitizers such as Rose Bengal and Indocyanine Green. Such high singlet oxygen generation capability under two-photon excitation was ascribed to their large two-photon absorption cross-sections. Polyvinylpyrrolidone (PVP) coated gold nanorods displayed excellent biocompatibility and high cellular uptake efficiency. The two-photon photodynamic therapy effect and two-photon fluorescence imaging properties of PVP coated gold nanorods have been successfully demonstrated on HeLa cells in vitro using fluorescence microscopy and indirect XTT assay method. These gold nanorods thus hold great promise for imaging guided two-photon photodynamic therapy for the treatment of various malignant tumors. PMID:23132010

Zhao, Tingting; Shen, Xiaoqin; Li, Lin; Guan, Zhenping; Gao, Nengyue; Yuan, Peiyan; Yao, Shao Q; Xu, Qing-Hua; Xu, Guo Qin

2012-11-06

310

Development of pH sensitive 2-(diisopropylamino)ethyl methacrylate based nanoparticles for photodynamic therapy  

NASA Astrophysics Data System (ADS)

Photodynamic therapy is an effective treatment for tumors that involves the administration of light-activated photosensitizers. However, most photosensitizers are insoluble and non-specific. To target the acid environment of tumor sites, we synthesized three poly(ethylene glycol) methacrylate-co-2-(diisopropylamino)ethyl methacrylate (PEGMA-co-DPA) copolymers capable of self-assembly to form pH sensitive nanoparticles in an aqueous environment, as a means of encapsulating the water-insoluble photosensitizer, meso-tetra(hydroxyphenyl)chlorin (m-THPC). The critical aggregation pH of the PEGMA-co-DPA polymers was 5.8-6.6 and the critical aggregation concentration was 0.0045-0.0089 wt% at pH 7.4. Using solvent evaporation, m-THPC loaded nanoparticles were prepared with a high drug encapsulation efficiency (approximately 89%). Dynamic light scattering and transmission electron microscopy revealed the spherical shape and 132 nm diameter of the nanoparticles. The in vitro release rate of m-THPC at pH 5.0 was faster than at pH 7.0 (58% versus 10% m-THPC released within 48 h, respectively). The in vitro photodynamic therapy efficiency was tested with the HT-29 cell line. m-THPC loaded PEGMA-co-DPA nanoparticles exhibited obvious phototoxicity in HT-29 colon cancer cells after light irradiation. The results indicate that these pH sensitive nanoparticles are potential carriers for tumor targeting and photodynamic therapy.

Peng, Cheng-Liang; Yang, Li-Yuan; Luo, Tsai-Yueh; Lai, Ping-Shan; Yang, Shu-Jyuan; Lin, Wuu-Jyh; Shieh, Ming-Jium

2010-04-01

311

Photosensitizer-conjugated silica-coated gold nanoclusters for fluorescence imaging-guided photodynamic therapy.  

PubMed

Multifunctional theranostics have recently been intensively explored to optimize the efficacy and safety of therapeutic regimens. In this work, a photo-theranostic agent based on chlorin e6 (Ce6) photosensitizer-conjugated silica-coated gold nanoclusters (AuNCs@SiO2-Ce6) is strategically designed and prepared for fluorescence imaging-guided photodynamic therapy (PDT). The AuNCs@SiO2-Ce6 shows the following features: i) high Ce6 photosensitizer loading; ii) no non-specific release of Ce6 during its circulation; iii) significantly enhanced cellular uptake efficiency of Ce6, offering a remarkably improved photodynamic therapeutic efficacy compared to free Ce6; iv) subcellular characterization of the nanoformula via both the fluorescence of Ce6 and plasmon luminescence of AuNCs; v) fluorescence imaging-guided photodynamic therapy (PDT). This photo-theranostics owns good stability, high water dispersibility and solubility, non-cytotoxicity, and good biocompatibility, thus facilitating its biomedical applications, particularly for multi-modal optical, CT and photoacoustic (PA) imaging-guided PDT or sonodynamic therapy. PMID:23523428

Huang, Peng; Lin, Jing; Wang, Shouju; Zhou, Zhijun; Li, Zhiming; Wang, Zhe; Zhang, Chunlei; Yue, Xuyi; Niu, Gang; Yang, Min; Cui, Daxiang; Chen, Xiaoyuan

2013-03-22

312

Postoperative Adjuvant Therapy after Transoral Robotic Resection for Oropharyngeal Carcinomas: Rationale and Current Treatment Approach  

Microsoft Academic Search

The advancement of transoral surgical techniques for the management of oropharyngeal carcinomas has raised questions about how adjuvant therapy can best be integrated. Some of these questions have come from the application of established oncologic principles of adjuvant therapy, and some are unique to the evolving experience with transoral surgery and in particular with the recent advancement of robotic surgery.

Harry Quon; Bert W. O’Malley Jr; Gregory S. Weinstein

2011-01-01

313

The need for optical imaging in the understanding and optimization of photodynamic therapy  

NASA Astrophysics Data System (ADS)

Optical excitation of chemicals provides reactive excited states, which can initiate chemical reactions and can also relax via radiative photophysical processes, providing the basis for fluorescence diagnostics. The best-known example of the former is Photodynamic Therapy (PDT), which is now approved for the treatment of a number of neoplastic and non-neoplastic pathologies. Although the concept of the use of photodynamic agents in diagnostics is as old as their use in therapy, the focused development of this aspect has been relatively recent. Typically, photodynamic agents have high triplet yields and relatively long triplet lifetimes (microsecond range), which allows them to interact and destroy molecular targets near them either directly or indirectly by producing other toxic molecular species. Associated with a high triplet yield is the fortunate attribute of most PDT agents in having low but finite fluorescence quantum yields. Fluorescence from these molecules may be used not only for diagnostics of disease de novo but also for guided surgery, PDT dosimetry and therapeutic monitoring. Other uses of fluorescence in PDT (not necessarily from the PDT agents) include the development of technologies that allow tracking of cells during treatment in vivo, studies of sub-cellular localization of molecules for mechanistic studies and photosensitizer tracking for specific targeting. An overview of studies on these aspects from different laboratories will be presented.

Solban, Nicolas; Sznycer-Taub, Nathaniel; Benavides, Juan Manuel; Chang, Sung; Georgakoudi, Irene; Hasan, Tayyaba

2005-04-01

314

Vaginal Speculum For Photodynamic Therapy And Method Of Using The Same  

DOEpatents

An improved vaginal speculum for photodynamic therapy of intraepithelial tissue and in particular vaginal, cervical and vulvar neoplasia utilizes a precisely and accurately positionable optic fiber through which a predetermined dose of light in the range of 620 to 700 nanometers is delivered over a controlled area which has been previously treated with photodynamic therapeutic substances. In particular, the neoplastic area has been treated with hematoporphyrin derivatives and other photosensitizers which are selectively taken into the cancerous tissue. Exposure to the appropriate wavelength laser light photoactivates the absorbed hematoporphyrins causing the release of singlet oxygen which internally oxidizes and ultimately causes cell death. The fiber optic tip from which the laser light is transmitted is precisely positioned within the body cavity at a predetermined distance from the intraepithelial neoplasia in order to obtain the appropriate spot size and location to minimize damage to healthy tissue and maximize damage to the selectively impregnated cancerous tissue.

Tadir, Yona (Irvine, CA); Berns, Michael W. (Trabuco Canyon, CA); Monk, Brad J. (Long Beach, CA); Profeta, Glen (Rancho Santa Margarita, CA); Tromberg, Bruce J. (Irvine, CA)

1995-10-17

315

Photophysical and photochemical properties of ?-(8-quinolinoxy) zinc phthalocyanine for photodynamic therapy  

NASA Astrophysics Data System (ADS)

The photophysical and photochemical properties of a newly developed photosensitizer ?-(8-quinolinoxy) zinc phthalocyanine (?-(8-QLO)PcZn) were investigated for application in photodynamic therapy (PDT). The maximal Q band for ?-(8-QLO)PcZn in dimethylformamide around 675 nm with the molar extinction coefficient of about 1.89×105 mol-1cm-1. The fluorescence quantum and singlet oxygen (1O2) yields were determined to be 0.18+/-0.02 and 0.62+/-0.03, respectively. ?-(8-QLO) PcZn has a diffuse cytoplasmic distribution in nasopharyngeal carcinoma C666-1 cells, and the efficient photodynamic cytotoxicity was observed. Our findings of this study suggest that ?-(8-QLO)PcZn is a promising second-generation photosensitizer for PDT.

Lv, Yuehui; Yu, Songlin; Lin, Huiyun; Li, Buhong; Xue, Jinping; Xie, Shusen

2009-02-01

316

[Endotoxin adsortion as adjuvant therapy in gram negative severe sepsis].  

PubMed

The mortality rate of severe sepsis and septic shock remains still high. Within the last years a better knowledge of its physiopathology and the implementation of a group of measures addressed to a fast identification and early treatment of the septic patients have proved to reduce mortality rate. Likewise, it continues being investigated in modulating the inflammatory response and limiting the harmful action of the bacterial products on the immune system. As a result of this research some endotoxin adsorber devices have been designed to control one of the most important targets that start the inflammatory cascade when gram negative microorganisms are involved.The usefulness that these endotoxin removal devices might have as adjuvant treatment in the Septic Syndrome and its applicability are reviewed in this paper. Likewise a profile of patient that might be to the benefit of this therapy is suggested according to the current knowledge. PMID:20844841

Candel, F J; Martínez-Sagasti, F; Borges, M; Maseda, E; Herrera-Gutiérrez, M; Garnacho-Montero, J; Maynar, F J; Zaragoza, R; Mensa, J; Azanza, J R

2010-09-01

317

Acetylsalicylic acid as an adjuvant therapy for schizophrenia  

PubMed Central

Background Findings from both epidemiological and basic research point to the possibility that NSAIDS impede the deterioration in schizophrenia. Methods To study the efficacy of acetylsalicylic acid we will perform a randomized placebo controlled double-blind add-on trial of 80 inpatients and outpatients with schizophrenia, schizophreniform or schizoaffective disorder. Patients will be 1:1 randomized to either 3 months 1000 mg acetylsalicylic acid per day or 3 months placebo, in addition to their regular antipsychotic treatment. All patients will receive pantoprazole treatment for gastroprotection. The outcomes of this study are 3-month change in psychotic and negative symptom severity, cognitive function, and several immunological parameters. This trial may (1) yield a new (adjuvant) therapy for schizophrenia and (2) add to the knowledge on the pathogenesis of this major psychiatric disorder.

Laan, Wijnand; Selten, Jean-Paul; Kahn, Rene S; Huisman, Anne-Margriet; Heijnen, Cobi J; Grobbee, Diederick E; Burger, Huibert

2006-01-01

318

Early experience in MRI-guided therapies of prostate cancer: HIFU, laser and photodynamic treatment  

PubMed Central

Abstract Prostate cancer screening has resulted in earlier diagnosis with lower-grade disease, leading to over-detection and over-treatment in a significant number of patients. Current whole-gland radical treatments are associated with significant rates of morbidity. The high prevalence of low-risk disease together with an inability to accurately identify those men harboring more aggressive cancers has led to tremendous research in low-morbidity focal therapies for prostate cancer. This review summarizes the early experiences with focal therapy with emphasis on early applications of laser, high-intensity focuses ultrasound, and photodynamic approaches.

Da Rosa, M.R.; Trachtenberg, J.; Chopra, R.

2011-01-01

319

Suppression of neointimal hyperplasia by photodynamic therapy: in vitro and in vivo results  

NASA Astrophysics Data System (ADS)

Proliferation of vascular smooth muscle cells (VSMCs) is the pathophysiogical basis of the restenoses which occur in 30-55% of patients undergone revascularisation. Prophylactic measures including pharmacotherapy, endovascular stenting and anti-gene therapy have so far failed to contain this problem. Photodynamic therapy (PDT) may selectively suppress VSMCs and decrease restenosis rates. We report 2 studies; the first examines the effect of PDT on an in-vitro model of NIH and the second involves using endoluminal ablation of an in-vivo model of experimental NIH of the rabbit's aorta.

Sobeh, Mohammed S.; Chan, Philip; Greenwald, Stephen E.; Ham, Robert J.; Wood, Alan J.; Cross, Frank W.; Hsiang, York N.

1994-07-01

320

Topical photodynamic therapy with 5-ALA in the treatment of arsenic-induced skin tumors  

NASA Astrophysics Data System (ADS)

A case of a 62-year-old woman suffering from psoriasis who was treated orally with arsenic 25 years ago is reported. The cumulative dose of arsenic trioxide was 800 mg. Since 10 years ago arsenic keratoses, basal cell carcinomas, Bowen's disease and invasive squamous cell carcinomas mainly on her hands and feet have developed, skin changes were clearly a sequence of arsenic therapy. Control of disease was poor, her right little finger had to be amputated. Topical photodynamic therapy with 5-aminolevulinic acid was performed on her right hand. Clinical and histological examinations 6 months after treatment showed an excellent cosmetic result with no signs of tumor residue.

Karrer, Sigrid; Szeimies, Rolf-Markus; Landthaler, Michael

1994-10-01

321

Topical photodynamic therapy with 5-ALA in the treatment of arsenic-induced skin tumors  

NASA Astrophysics Data System (ADS)

A case of a 62-year-old woman suffering from psoriasis who was treated orally with arsenic 25 years ago is reported. The cumulative dose of arsenic trioxide was 800 mg. Since 10 years ago arsenic keratoses, basal cell carcinomas, Bowen's disease and invasive squamous cell carcinomas mainly on her hands and feet have developed, skin changes were clearly a sequence of arsenic therapy. Control of disease was poor, her right little finger had to be amputated. Topical photodynamic therapy with 5-aminolevulinic acid was performed on her right hand. Clinical and histological examinations 6 months after treatment showed an excellent cosmetic result with no signs of tumor residue.

Karrer, Sigrid; Szeimies, Rolf-Markus; Landthaler, Michael

1995-03-01

322

Pheophorbides as photosensitizers for the photodynamic therapy of tumors  

NASA Astrophysics Data System (ADS)

Quantum yields for formation of singlet molecular oxygen have been measured for sodium pheophorbides (Na-Phdes) a and b in aqueous and non-aqueous media. Measurements have been made for both steady-state and pulsed laser excitation with the resultant singlet molecular oxygen being detected by photo-oxygenation reactions or time-resolved luminescence spectroscopy, respectively. Singlet oxygen production sensitized by Na-Phdes a or b is insignificant in aqueous media but occurs with a good efficiency in organic solvents. Plasmid DNA is efficiently photocleaved by Na-Phdes a and b in the absence of oxygen as well as in the presence of oxygen. Fluorescence microscopic observation shows a rapid incorporation of Na-Phde a into nuclei, mitochondria, and lysosome of human oral mucosa cells. In contrast Na-Phde b is incorporated only into the plasma membrane. The photodynamic activity of these pigments in living tissues is probably determined by the monomeric pigment molecules formed in hydrophobic cellular structures.

Tanielian, Charles; Wolff, Christian; Kobayashi, Masami

1995-01-01

323

Clinical and experimental results of photodynamic therapy in neurosurgery  

NASA Astrophysics Data System (ADS)

Since 1984, 58 patients bearing malignant brain tumors were treated 70 times with photodynamic treatment (PDT). The patient population consisted of 11 primary glioblastoma WHO grade IV, 39 recurrent glioblastomas, 3 malignant meningiomas, 3 recurrent melanomas, and 2 metastasis of carcinomas. The patients were sensitized with hematoporphyrin derivative (HPD) 2.5 mg/bodyweight 24 - 48 hours prior to craniotomy and tumor resection. The light-irradiation was performed by an Argon pumped dye laser (Aurora M) superficially and/or interstitially at a dose ranging up to 250 J/cm2. The median survival of primary glioblastomas was 19 months and for recurrent glioblastomas 7 months, respectively. Malignant meningiomas, as well as melanomas, did not benefit from PDT, whereas one patient with a metastasis of an adenocarcinoma is still recurrence free since 18 months, the other recurred after 6 months. HPD extractions of the tumor revealed significantly different concentrations among the various tumors, but also between identical histologies. The survival, however, did not correlate with the HPD concentration in the tumor. PDT prolongs median survival of primary glioblastomas significantly, and doubles the survival of recurrent high grade gliomas. Furthermore the treatment of recurrent low grade gliomas and metastasis to the brain are promising indications for PDT.

Kostron, Herwig; Hochleitner, B. W.; Obwegeser, Alois; Seiwald, M.

1994-10-01

324

Clinical and experimental results of photodynamic therapy in neurosurgery  

NASA Astrophysics Data System (ADS)

Since 1984, 58 patients bearing malignant brain tumors were treated 70 times with photodynamic treatment (PDT). The patient population consisted of 11 primary glioblastoma WHO grade IV, 39 recurrent glioblastomas, 3 malignant meningiomas, 3 recurrent melanomas, and 2 metastasis of carcinomas. The patients were sensitized with hematoporphyrin derivative (HPD) 2.5 mg/bodyweight 24 - 48 hours prior to craniotomy and tumor resection. The light-irradiation was performed by an Argon pumped dye laser (Aurora M) superficially and/or interstitially at a dose ranging up to 250 J/cm2. The median survival of primary glioblastomas was 19 months and for recurrent glioblastomas 7 months, respectively. Malignant meningiomas, as well as melanomas, did not benefit from PDT, whereas one patient with a metastasis of an adenocarcinoma is still recurrence free since 18 months, the other recurred after 6 months. HPD extractions of the tumor revealed significantly different concentrations among the various tumors, but also between identical histologies. The survival, however, did not correlate with the HPD concentration in the tumor. PDT prolongs median survival of primary glioblastomas significantly, and doubles the survival of recurrent high grade gliomas. Furthermore the treatment of recurrent low grade gliomas and metastasis to the brain are promising indications for PDT.

Kostron, Herwig; Hochleitner, B. W.; Obwegeser, A.; Seiwald, M.

1995-03-01

325

Photodynamic therapy of malignant brain tumours: A complementary approach to conventional therapies.  

PubMed

The poor outcome of primary malignant brain tumours is predominantly due to local invasion and local recurrence and their prognosis is highly dependent on the degree of resection. They have no border and, at best, a marginal zone that remains invisible to the surgeon. Photodynamic therapy (PDT) appears to be an interesting modality to fill the need for a targeted treatment that may reduce recurrence and extend survival with minimal side effects. In this review, we summarize the different technologies of brain tumour PDT employed such as interstitial PDT, and PDT-associated surgical resection, describing new light delivery devices. The role of dosimetry - one of the key factors behind successful brain tumour PDT - is discussed. This can be achieved by integrating results from in vivo studies. In this context, the development of new therapeutic photosensitizer delivery systems is also an area of significant research interest. Multifunctionality can be engineered into a single nanoplatform to provide tumour-specific detection, treatment, and follow-up. Such multitasking systems appear to be complementary to conventional technologies. PMID:22858248

Bechet, Denise; Mordon, Serge R; Guillemin, François; Barberi-Heyob, Muriel A

2012-08-01

326

Systems Approach to Optimization of the Regimen of Photodynamic Therapy of Solid Sarcoma M-1 Using the “Fotosens” Preparation as Example  

Microsoft Academic Search

A systems analysis of the interaction between objects (tumor, healthy tissue, radiation, and photosensitizer of the singlet state of oxygen) involved in photodynamic therapy was carried out. A schematic diagram of the biologically significative processes proceeding under these circumstances was proposed. This schematic diagram can serve as a basis for a systems approach to the optimization of photodynamic therapy. The

T. S. Lagoda; M. A. Kaplan; Ya. V. Krivosheev; L. P. Zhavoronkov; V. B. Taraban; M. B. Bokova; V. M. Posadskaya

2001-01-01

327

Two-photon excitation of chlorin-e6-C15 monomethyl ester for photodynamic therapy  

NASA Astrophysics Data System (ADS)

Two-photon-induced fluorescence spectrum and lifetime of Chlorin-e6-C15 Monomethyl Ester in tetrahydrofura (THF) are experimentally examined with femtosecond laser pulses at 800 nm from a Ti:sapphire laser. The two-photon excited fluorescence spectra of the molecule are basically similar to those obtained by one-photon excitation. The lifetimes of two-photon and one-photon excitation fluorescence of this molecule in the solution are of the order of 5.2 ns and 4.8 ns respectively. Our experimental results indicate that the two-photon-induced photodynamic processes of Chlorin-e6-C15 Monomethyl Ester are similar to one-photon-induced photodynamic processes. The two-photon absorption cross section of the molecule is measured at 800 nm as about ?2? ? 29.1 x 10-50 cm4 • s/photon. As an example for two-photon photodynamic therapy, we also further examine the cell-damaging effects of the Ester. Our preliminary results of cell viability test indicate that Chlorin-e6-C15 Monomethyl Ester can effectively damage the liver cancer cells BEL-7402 under two-photon irradiation. Our results suggest Chlorin-e6-C15 Monomethyl Ester may become a potential two-photon phototherapeutic agent.

Chen, Ping; Zhao, P. D.; Guo, P.; Lin, Lie; Liu, J. Wei; Yu, Q.

2005-01-01

328

Concepts and Principles of Photodynamic Therapy as an Alternative Antifungal Discovery Platform  

PubMed Central

Opportunistic fungal pathogens may cause superficial or serious invasive infections, especially in immunocompromised and debilitated patients. Invasive mycoses represent an exponentially growing threat for human health due to a combination of slow diagnosis and the existence of relatively few classes of available and effective antifungal drugs. Therefore systemic fungal infections result in high attributable mortality. There is an urgent need to pursue and deploy novel and effective alternative antifungal countermeasures. Photodynamic therapy (PDT) was established as a successful modality for malignancies and age-related macular degeneration but photodynamic inactivation has only recently been intensively investigated as an alternative antimicrobial discovery and development platform. The concept of photodynamic inactivation requires microbial exposure to either exogenous or endogenous photosensitizer molecules, followed by visible light energy, typically wavelengths in the red/near infrared region that cause the excitation of the photosensitizers resulting in the production of singlet oxygen and other reactive oxygen species that react with intracellular components, and consequently produce cell inactivation and death. Antifungal PDT is an area of increasing interest, as research is advancing (i) to identify the photochemical and photophysical mechanisms involved in photoinactivation; (ii) to develop potent and clinically compatible photosensitizers; (iii) to understand how photoinactivation is affected by key microbial phenotypic elements multidrug resistance and efflux, virulence and pathogenesis determinants, and formation of biofilms; (iv) to explore novel photosensitizer delivery platforms; and (v) to identify photoinactivation applications beyond the clinical setting such as environmental disinfectants.

Dai, Tianhong; Fuchs, Beth B.; Coleman, Jeffrey J.; Prates, Renato A.; Astrakas, Christos; St. Denis, Tyler G.; Ribeiro, Martha S.; Mylonakis, Eleftherios; Hamblin, Michael R.; Tegos, George P.

2012-01-01

329

Photodynamic therapy of vein grafts: Suppression of intimal hyperplasia of the vein graft but not the anastomosis  

Microsoft Academic Search

Purpose: There is no clinically useful therapy for the suppression of vein bypass graft intimal hyperplasia (IH). Photodynamic therapy (PDT), a technique that uses light to activate otherwise biologically inert photosensitizers to produce cytotoxic effects, has been demonstrated to successfully inhibit experimental IH in balloon-injured arteries. The purpose of this study was to investigate the efficacy of PDT as a

Glenn M. LaMuraglia; Michael L. Klyachkin; Farzin Adili; William M. Abbott

1995-01-01

330

The results of radical retropubic prostatectomy and adjuvant therapy for pathologic Stage C prostate cancer  

Microsoft Academic Search

Purpose: The results of therapy in 288 men with pathologic Stage C prostate cancer who underwent radical retropubic prostatectomy (RRP) were analyzed to determine the effects of adjuvant therapy.Methods and Materials: Twenty-seven of the 288 patients received preoperative neoadjuvant hormonal therapy (leuprolide acetate). Postoperatively, 60 patients received adjuvant radiotherapy (RT) to the prostate bed. Follow-up ranged from 3 to 83

Steven E. Schild; William W. Wong; Gordon L. Grado; Michele Y. Halyard; Donald E. Novicki; Scott K. Swanson; Thayne R. Larson; Robert G. Ferrigni

1996-01-01

331

Combination of photodynamic and ultrasonic therapy for treatment of infected wounds in animal model  

NASA Astrophysics Data System (ADS)

One of the important problems of modern medicine is treatment of infected wounds. There are many diversified expedients of treatment, but none of them obey the modern physician completely. The aim of this study is to develop and test a new combined method of photodynamic ultrasonic therapy (PDUST) for treatment of infected wounds with focus on experimental trials. PDUST is based on a combination of two methods: photodynamic (PD) therapy (PDT) with photosensitizer and low frequency ultrasonic (US) therapy with antibiotic as tools for treatment of wounds and effectively killing bacteria. The main parameters are: US frequency - 26.5 kHz; US tip elongation - 40+/-20 ?m wavelength of light emitting diodes (LED) array - 660+/-10 nm; light intensity on biotissue surface - 1-2 mW/cm2; photosensitizer - an aluminum disulfonated phtalocyanine dissolved in a physiological solution in concentration 10 mg/l. The experiments were carried out with 70 male chinchilla rabbits divided into 7 groups, thus the dynamics of wounds healing were studied in different modes of PDUST. The PD and US methods supplement each other and in conjunction provide additive and especially synergetic effects. The experimental data demonstrated advantages of new technology in comparison with conventional methods in cases of treatment of extended suppurative inflammatory and profound wounds. The more detailed study of PDUST method's mechanism, which is based on low intensity of LED light, PD therapy and US influence is required.

Menyaev, Yulian A.; Zharov, Vladimir P.

2006-03-01

332

Minimally-invasive technologies in uro-oncology: The role of cryotherapy, HIFU and photodynamic therapy in whole gland and focal therapy of localised prostate cancer  

Microsoft Academic Search

The use of minimally-invasive ablative therapies in localised prostate cancer offer potential for a middle ground between active surveillance and radical therapy. This article reviews the evidence for cryotherapy, high intensity focused ultrasound (HIFU) and photodynamic therapy in the treatment of localised prostate cancer. These ablative technologies can deliver a minimally invasive, day case treatment with effective early cancer control

Hashim Uddin Ahmed; Caroline Moore; Mark Emberton

2009-01-01

333

Telephone Counseling as Adjuvant Treatment for Nicotine Replacement Therapy in a “Real-World” Setting  

Microsoft Academic Search

Background. Physicians prescribing nicotine replacement therapy (NRT), or health plans covering NRT, often want their patients to receive adjuvant behavioral treatment. However, how to do that in a “real world” is unclear. This paper reports results from a public health program that uses proactive telephone counseling as support for physician advice and provides adjuvant treatment for NRT users.Methods. Participants were

Shu-Hong Zhu; Gary Tedeschi; Christopher M. Anderson; Bradley Rosbrook; Michael Byrd; Cynthia E. Johnson; Elsa Gutiérrez-Terrell

2000-01-01

334

KillerRed and miniSOG as genetically encoded photosensitizers for photodynamic therapy of cancer  

NASA Astrophysics Data System (ADS)

Despite of the success of photodynamic therapy (PDT) in cancer treatment, the problems of low selective accumulation of a photosensitizer in a tumor and skin phototoxicity have not resolved yet. The idea of encoding of a photosensitizer in genome of cancer cells is attractive, particularly because it can provide highly selective light induced cell killing. This work is aimed at the development of new approach to PDT of cancer, namely to using genetically encoded photosensitizers. A phototoxicity of red fluorescent GFP-like protein KillerRed and FMN-binding protein miniSOG was investigated on HeLa tumor xenografts in nude mice. The tumors were generated by subcutaneous injection of HeLa cells stably expressing the phototoxic proteins. The tumors were irradiated with 594 nm or 473 nm laser at 150 mW/cm2 for 20 or 30 min, repeatedly. Fluorescence intensity of the tumors was measured in vivo before and after each treatment procedure. Detailed pathomorphological analysis was performed 24 h after the therapy. On the epi-fluorescence images in vivo photobleaching of both proteins was observed indicating photodynamic reaction. Substantial pathomorphological abnormalities were found in the treated KillerRed-expressing tumor tissue, such as vacuolization of cytoplasm, cellular and nuclear membrane destruction, activation of apoptosis. In contrast, miniSOG-expressing tumors displayed no reaction to PDT, presumably due to the lack of FMN cofactor needed for fluorescence recovery of the flavoprotein. The results are of interest for photodynamic therapy as a proof of possibility to induce photodamages in cancer cells in vivo using genetically encoded photosensitizers.

Shirmanova, Marina V.; Serebrovskaya, Ekaterina O.; Snopova, Ludmila B.; Kuznetsova, Maria M.; Ryumina, Alina P.; Turchin, Ilya V.; Sergeeva, Ekaterina A.; Ignatova, Nadezhda I.; Klementieva, Natalia V.; Lukyanov, Konstantin A.; Lukyanov, Sergey A.; Zagaynova, Elena V.

2013-06-01

335

Photofrin-mediated photodynamic therapy for treatment of early stage laryngeal malignancies  

Microsoft Academic Search

To evaluate the efficacy of PHOTOFRIN-mediated photodynamic therapy (PDT) for the treatment of Tis-T1N0M0 squamous cell carcinoma\\u000a (SqCCa) of the larynx in patients not amenable to or who failed conventional head and neck treatment. This is a retrospective\\u000a study of 26 patients with early stage Tis-T1 SqCCa of the larynx treated with PHOTOFRIN-mediated PDT. Intravenous PHOTOFRIN\\u000a (porfimer-sodium) (dose 2.0 mg\\/kg) was

Vanessa Gayl Schweitzer; Melissa L. Somers

2010-01-01

336

Combined intravitreal bevacizumab and photodynamic therapy for neovascular age-related macular degeneration  

Microsoft Academic Search

Background  Our aim was to evaluate the short-term safety and efficacy of combined photodynamic therapy (PDT) with verteporfin and intravitreal\\u000a bevacizumab in neovascular age-related macular degeneration (AMD).\\u000a \\u000a \\u000a \\u000a Methods  A prospective non-randomized interventional case series of 30 eyes of 30 patients with choroidal neovascularization (CNV)\\u000a caused by AMD was studied. All patients were treated with PDT followed by an intravitreal injection of bevacizumab

Markus S. Ladewig; Stefanie E. Karl; Victoria Hamelmann; Hans-Martin Helb; Hendrik P. N. Scholl; Frank G. Holz; Nicole Eter

2008-01-01

337

Lightpipe device for delivery of uniform illumination for photodynamic therapy of the oral cavity  

PubMed Central

A compact and efficient lightpipe device to deliver light to the human oral cavity for photodynamic therapy was designed and fabricated, having dimensions 6.8 mm × 6.8 mm × 46 mm. An average irradiance of 76 mW/cm2 with an average deviation of 5% was measured on a square 25 mm2 treatment field for an input power of 100 mW. The device limits irradiation of healthy tissue and offers potential for improvement over the current treatment procedure, which requires shielding of the whole cavity to avoid damage to healthy tissue.

Canavesi, Cristina; Cassarly, William J.; Foster, Thomas H.; Rolland, Jannick P.

2011-01-01

338

Poly(ethylene glycol) conjugated nano-graphene oxide for photodynamic therapy  

Microsoft Academic Search

A novel methoxy-poly(ethylene glycol) modified nano-graphene oxide (NGO-mPEG) was designed and synthesized as a photosensitizer\\u000a (PS) carrier for photodynamic therapy of cancer. NGO with a size below 200 nm was prepared using a modified Hummers’ method.\\u000a NGO was observed by AFM to exhibit a structure with single-layer graphene oxide sheets down to a few nanometers in height.\\u000a Hydrophilic mPEG conjugation

HaiQing Dong; ZhiLei Zhao; HuiYun Wen; FangFang Guo; AiJun Shen; Frank Pilger; Chao Lin; DongLu Shi

2010-01-01

339

Use of Photodynamic Therapy for Treatment of Actinic Keratoses in Organ Transplant Recipients  

PubMed Central

Solid organ transplant recipients are predisposed to actinic keratoses (AK) and nonmelanoma skin cancers, owing to the lifelong immunosuppression required. Today, increasing numbers of organ transplants are being performed and organ transplant recipients (OTRs) are surviving much longer. Photodynamic therapy (PDT) is proving a highly effective treatment modality for AK amongst this susceptible group of patients. Following an overview of the pathogenesis of AK amongst OTRs, the authors review current safety and efficacy data and how this relates to the role of PDT for the treatment of AK in OTRs.

Wlodek, Christina; Ali, Faisal R.; Lear, John T.

2013-01-01

340

Photodynamic therapy on bladder cancer cells: further studies on the performance of Coimbra sensitizers  

NASA Astrophysics Data System (ADS)

Following previous studies where we developed some high performance porphyrin derivatives for photodynamic therapy demonstrating their activity in different cell lines, we now extend our attention to CRL1472 bladder cancer line. In this work the phototoxicity of several diaryl and tetraarylporphyrins with different structures were evaluated with different incubation times. The phototoxicity observed was not directly related to the concentration of photosensitizer inside cells. Uptake studies demonstrate that the brominated derivative 2 which despite the most efficient photosensitizer presents a poor tendency to enter into cells.

D'A. Rocha Gonsalves, Antonio M.; Serra, Arménio C.; Pineiro, Marta; Botelho, M. Filomena

2010-04-01

341

Prostate Specific Membrane Antigen-Targeted Photodynamic Therapy Induces Rapid Cytoskeletal Disruption  

PubMed Central

Prostate-specific membrane antigen (PSMA), an established enzyme-biomarker for prostate cancer, has attracted considerable attention as a target for imaging and therapeutic applications. We aimed to determine the effects of PSMA-targeted photodynamic therapy (PDT) on cytoskeletal networks in prostate cancer cells. PSMA-targeted PDT resulted in rapid disruption of microtubules (?-/?-tubulin), microfilaments (actin), and intermediate filaments (cytokeratin 8/18) in the cytoplasm of LNCaP cells. The collapse of cytoplasmic microtubules and the later nuclear translocation of ?-/?-tubulin were the most dramatic alternation. It is likely that these early changes of cytoskeletal networks are partly involved in the initiation of cell death.

Liu, Tiancheng; Wu, Lisa Y.; Berkman, Clifford E.

2010-01-01

342

Facial skin rejuvenation: Ablative laser resurfacing, chemical peels, or photodynamic therapy? Facts and controversies.  

PubMed

Patients and cosmetic surgeons continue to develop innovative devices and techniques in search of the elusive fountain of youth. Our efforts in the past decade can be distilled to three primary approaches: refinement of existing technologies (ablative lasers); refinement of tried-and-true techniques (chemical peeling); and innovative use of new technologies (photorejuvenation). In this contribution, the authors discuss how these three approaches are used to achieve facial skin rejuvenation. Specifically, the authors compare and contrast the clinical benefits and disadvantages of the ablative fractionated and unfractionated carbon dioxide resurfacing lasers, medium-depth and deep chemical peeling, and the combination of photodynamic therapy with intense-pulsed light. PMID:24160279

Hassan, Khaled M; Benedetto, Anthony V

343

Solar keratoses: Photodynamic therapy, cryotherapy, 5-fluorouracil, imiquimod, diclofenac, or what? Facts and controversies.  

PubMed

Actinic keratosis is a common dermatologic condition that may regress, remain stable, or progress to squamous cell carcinoma. Some question whether all actinic keratoses should be routinely treated, whereas others contend that the unpredictable natural history of this disease necessitates treatment to prevent malignant transformation. Available treatments include photodynamic therapy, cryotherapy, 5-fluorouracil, imiquimod, and diclofenac. Each of these options has its advantages and disadvantages, although they all have a place in the management of actinic keratosis. An overview of these treatment modalities is presented, as are the controversies surrounding the treatment of actinic keratosis. PMID:24160275

Schmitt, Adam R; Bordeaux, Jeremy S

344

Toluidine blue-mediated photodynamic therapy of oral wound infections in rats  

Microsoft Academic Search

The purpose of this study was to examine the effect of toluidine blue (TB)-mediated photodynamic therapy (PDT) on oral wound\\u000a infections in rats. The study called for a combination treatment of a 1mg\\/ml solution of TB with a red light at three intensity\\u000a settings of 12 J\\/cm2, 24 J\\/cm2 and 48 J\\/cm2. In the group that was given the highest light dose of

J. Lin; L. J. Bi; Z. G. Zhang; Y. M. Fu; T. T. Dong

2010-01-01

345

Photodynamic therapy in the management of lesions of the head and neck.  

PubMed

Photodynamic therapy (PDT) is a promising and effective treatment for lesions of the head and neck. It uses illumination with light of a specific wavelength, which activates a photosensitising drug in the presence of oxygen. It can be used in combination with other treatments or on its own, and results in the cellular destruction of the lesion through a free-radical process. Photosensitisers can be applied topically or given systemically depending on the lesion being treated. Results indicate that PDT is an effective adjunct to standard conventional treatments. We review its use. PMID:23245464

Green, Ben; Cobb, Alistair R M; Hopper, Colin

2012-12-11

346

Paclitaxel augments cytotoxic effect of photodynamic therapy using verteporfin in gastric and bile duct cancer cells.  

PubMed

Photodynamic therapy (PDT) shows a limited antitumor effect in treating gastrointestinal tumors because of improper light penetration or insufficient photosensitizer uptake. The aim of this study was to evaluate the cytotoxic effect of PDT combined with paclitaxel on in vitro cancer cells. In vitro photodynamic therapy was performed in gastric cancer cells (NCI-N87) and bile duct cancer cells (YGIC-6B) using verteporfin (2 ug mL(-1)) and a PTH light source (1 000 W, Oriel Co.) with 665-675 nm narrow band pass filter. Cytotoxicity was compared using the MTT assay between cancer cells treated with PDT alone or pretreated with paclitaxel (IC(25)). Apoptotic changes were evaluated using DAPI staining, DNA fragmentation analysis, Annexin V-FITC apoptosis assay, cell cycle analysis, and western blots for cytochrome c, Bax, and Bid. The PDT-induced cytotoxicity was potentiated by pretreating with low dose paclitaxel (P < 0.001). The enhanced cytotoxicity was due to an augmented apoptotic response mediated by exaggerated cytochrome c released from mitochondria, without Bax or Bid activation. These results show that paclitaxel pretreatment enhances PDT-mediated cancer therapy. PMID:18597023

Park, Seungwoo; Hong, Sung Pil; Oh, Tae Yoon; Bang, Seungmin; Chung, Jae Bock; Song, Si Young

2008-05-15

347

Molecular effectors of multiple cell death pathways initiated by photodynamic therapy.  

PubMed

Photodynamic therapy (PDT) is a recently developed anticancer modality utilizing the generation of singlet oxygen and other reactive oxygen species, through visible light irradiation of a photosensitive dye accumulated in the cancerous tissue. Multiple signaling cascades are concomitantly activated in cancer cells exposed to the photodynamic stress and depending on the subcellular localization of the damaging ROS, these signals are transduced into adaptive or cell death responses. Recent evidence indicates that PDT can kill cancer cells directly by the efficient induction of apoptotic as well as non-apoptotic cell death pathways. The identification of the molecular effectors regulating the cross-talk between apoptosis and other major cell death subroutines (e.g. necrosis, autophagic cell death) is an area of intense research in cancer therapy. Signaling molecules modulating the induction of different cell death pathways can become useful targets to induce or increase photokilling in cancer cells harboring defects in apoptotic pathways, which is a crucial step in carcinogenesis and therapy resistance. This review highlights recent developments aimed at deciphering the molecular interplay between cell death pathways as well as their possible therapeutic exploitation in photosensitized cells. PMID:17693025

Buytaert, Esther; Dewaele, Michael; Agostinis, Patrizia

2007-07-06

348

Clinical assessment of the efficacy of photodynamic therapy in the treatment of oral lichen planus.  

PubMed

The study objective was clinical assessment of the efficacy of photodynamic therapy (PDT) in the treatment of oral lichen planus (OLP). There were 23 patients aged 31-82 included in the study with oral lichen planus diagnosed clinically and histopathologically. In all patients photodynamic therapy was performed with the use of chlorin e6 (Photolon(®)), containing 20 % chlorin e6 and 10 % dimethyl sulfoxide as a photosensitizer. PDT was performed using a semiconductor laser, with power up to 300 mW and a wavelength of 660 nm. A series of illumination sessions was conducted with the use of superficial light energy density of 90 J/cm(2). Changes of lesion size were monitored at one, two, five, and ten PDT appointments from the series of ten according to the authors' own method. The sizes of clinical OLP lesions exposed to PDT were reduced significantly (on average by 55 %). The best effects were observed for the lesions on the lining mucosa (57.6 %). The therapy was statistically significantly less effective when masticatory mucosa was affected (reduction, 30.0 %). Due to substantial efficacy and noninvasiveness, PDT can be useful in the treatment of OLP lesions. PMID:22814895

Sobaniec, Stefan; Bernaczyk, Piotr; Pietruski, Jan; Cholewa, Magdalena; Skurska, Anna; Doli?ska, Ewa; Duraj, Ewa; Tokajuk, Gra?yna; Paniczko, Agnieszka; Olszewska, Ewa; Pietruska, Ma?gorzata

2012-07-20

349

Baylor study finds obesity linked to worse survival outcomes in breast cancer adjuvant therapy:  

Cancer.gov

Obesity may contribute to worse survival outcomes in early stage breast cancer patients who have received adjuvant therapy to treat their disease, said researchers from the Lester and Sue Smith Breast Center at Baylor College of Medicine.

350

Virus Capsids as Targeted Nanoscale Delivery Vessels of Photoactive Compounds for Site-Specific Photodynamic Therapy  

NASA Astrophysics Data System (ADS)

The research presented in this work details the use of a viral capsid as an addressable delivery vessel of photoactive compounds for use in photodynamic therapy. Photodynamic therapy is a treatment that involves the interaction of light with a photosensitizing molecule to create singlet oxygen, a reactive oxygen species. Overproduction of singlet oxygen in cells can cause oxidative damage leading to cytotoxicity and eventually cell death. Challenges with the current generation of FDA-approved photosensitizers for photodynamic therapy primarily stem from their lack of tissue specificity. This work describes the packaging of photoactive cationic porphyrins inside the MS2 bacteriophage capsid, followed by external modification of the capsid with cancer cell-targeting G-quadruplex DNA aptamers to generate a tumor-specific photosensitizing agent. First, a cationic porphyrin is loaded into the capsids via nucleotide-driven packaging, a process that involves charge interaction between the porphyrin and the RNA inside the capsid. Results show that over 250 porphyrin molecules associate with the RNA within each MS2 capsid. Removal of RNA from the capsid severely inhibits the packaging of the cationic porphyrins. Porphyrin-virus constructs were then shown to photogenerate singlet oxygen, and cytotoxicity in non-targeted photodynamic treatment experiments. Next, each porphyrin-loaded capsid is externally modified with approximately 60 targeting DNA aptamers by employing a heterobifunctional crosslinking agent. The targeting aptamer is known to bind the protein nucleolin, a ubiquitous protein that is overexpressed on the cell surface by many cancer cell types. MCF-7 human breast carcinoma cells and MCF-10A human mammary epithelial cells were selected as an in vitro model for breast cancer and normal tissue, respectively. Fluorescently tagged virus-aptamer constructs are shown to selectively target MCF-7 cells versus MCF-10A cells. Finally, results are shown in which porphyrin-virus-aptamer constructs selectively target and kill cancer cells versus non-cancer cells. Specifically, the results show that MS2 is a viable candidate as an addressable nanodelivery vessel of photoactive compounds, and the implications are that the nucleotide-driven packaging approach for modifying MS2 can be used to impart new functionalities for a host of diagnostic or therapeutic applications.

Cohen, Brian A.

351

Photodynamic Therapy as an Alternative Treatment for Cutaneous Sarcoidosis  

Microsoft Academic Search

Sarcoidosis is a systemic granulomatous disease. In more than 90% of the cases, sarcoidosis affects the lung with bilateral hilar adenopathy, while skin involvement occurs in about 25% of the cases. Whereas sarcoidosis of the lung is often successfully treated with oral corticosteroids, therapy of cutaneous sarcoidosis is frequently frustrating because some of the lesions may be refractory to treatment

Dagmar Wilsmann-Theis; Thomas Bieber; Natalija Novak

2008-01-01

352

Barrett's esophagus: photodynamic therapy for ablation of dysplasia, reduction of specialized mucosa and treatment of superficial esophageal cancer  

NASA Astrophysics Data System (ADS)

Fifteen patients with Barrett's esophagus and dysplasia were treated with photodynamic therapy. Four patients also had early, superficial esophageal cancers and 5 had esophageal polyps. Light was delivered via a standard diffuser or a centering esophageal balloon. Eight patients maintained on omeprazole and followed for 6 - 54 months are the subject of this report. Photodynamic therapy ablated dysplastic or malignant mucosa in patients with superficial cancer. Healing and partial replacement of Barrett's mucosa with normal squamous epithelium occurred in all patients and complete replacement with squamous epithelium was found in two. Side effects included photosensitivity and mild-moderate chest pain and dysphagia for 5 - 7 days. In three patients with extensive circumferential mucosal ablation in the proximal esophagus, healing was associated with esophageal strictures which were treated successfully by esophageal dilation. Strictures were not found in the distal esophagus. Photodynamic therapy combined with long-term acid inhibition provides effective endoscopic therapy of Barrett's mucosal dysplasia and superficial (Tis-T1) esophageal cancer. The windowed centering balloon improves delivery of photodynamic therapy to diffusely abnormal esophageal mucosa.

Overholt, Bergein F.; Panjehpour, Masoud

1994-10-01

353

Barrett's esophagus: photodynamic therapy for ablation of dysplasia, reduction of specialized mucosa and treatment of superficial esophageal cancer  

NASA Astrophysics Data System (ADS)

Fifteen patients with Barrett's esophagus and dysplasia were treated with photodynamic therapy. Four patients also had early, superficial esophageal cancers and 5 had esophageal polyps. Light was delivered via a standard diffuser or a centering esophageal balloon. Eight patients maintained on omeprazole and followed for 6 - 54 months are the subject of this report. Photodynamic therapy ablated dysplastic or malignant mucosa in patients with superficial cancer. Healing and partial replacement of Barrett's mucosa with normal squamous epithelium occurred in all patients and complete replacement with squamous epithelium was found in two. Side effects included photosensitivity and mild-moderate chest pain and dysphagia for 5 - 7 days. In three patients with extensive circumferential mucosal ablation in the proximal esophagus, healing was associated with esophageal strictures which were treated successfully by esophageal dilation. Strictures were not found in the distal esophagus. Photodynamic therapy combined with long-term acid inhibition provides effective endoscopic therapy of Barrett's mucosal dysplasia and superficial (Tis-T1) esophageal cancer. The windowed centering balloon improves delivery of photodynamic therapy to diffusely abnormal esophageal mucosa.

Overholt, Bergein F.; Panjehpour, Masoud

1995-03-01

354

Adjuvant therapy for locally advanced renal cell cancer: A systematic review with meta-analysis  

Microsoft Academic Search

Background  Many adjuvant trials have been undertaken in an attempt to reduce the risk of recurrence among patients who undergo surgical\\u000a resection for locally advanced renal cancer. However, no clear benefit has been identified to date. This systematic review\\u000a was conducted to examine the exact role of adjuvant therapy in renal cancer setting.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Randomized controlled trials were searched comparing adjuvant therapy

Adolfo JO Scherr; Joao Paulo SN Lima; Emma C Sasse; Carmen SP Lima; André D Sasse

2011-01-01

355

From adjuvant therapy to breast cancer prevention: BCPT and STAR.  

PubMed

The continued widespread prevalence of breast cancer supports placing a high priority on research aimed at its primary prevention, particularly among women who are at increased risk for developing this disease. The suggestion of potential agents for the primary chemoprevention of breast cancer evolved out of the treatment setting. Extensive experience with tamoxifen, a first-generation selective estrogen receptor modulator (SERM) showing efficacy, first, in the treatment of advanced breast cancer and, subsequently, as adjuvant therapy for early stage disease established the safety of this agent. Cumulative data from multiple adjuvant studies documented the efficacy of tamoxifen in reducing second primary breast cancers in the contralateral breast, supporting its potential as a chemopreventive agent for breast cancer. The safety and second primary data on tamoxifen, together with extensive information on its pharmacokinetics, metabolism, and antitumor effects, as well as its potentially beneficial effects on lipid metabolism and osteoporosis, led the National Surgical Adjuvant Breast and Bowel Project (NSABP) to select tamoxifen for testing in the first prospective randomized phase III trial of the efficacy of a chemopreventive agent for preventing breast cancer in women at increased risk of the disease. Accordingly, in 1992 the NSABP started the Breast Cancer Prevention Trial (P-1) in which 13,388 women > or = 35 years of age who were at increased risk of breast cancer according to Gail model risk factors [family history, age, and personal history (i.e., age at first birth, age at menarche, previous breast biopsies)] were randomized to tamoxifen 20 mg/day or placebo for 5 years. Through 69 months of follow-up tamoxifen reduced the risk of invasive breast cancer, primarily estrogen receptor-positive tumors, by 49% (two-sided p < 0.00001). Tamoxifen reduced the risk of noninvasive breast cancer by 50% (two-sided p < 0.002). In addition, tamoxifen reduced fractures of the hip, radius, and spine, but it had no effect on the rate of ischemic heart disease. As previously shown, the rates of endometrial cancer and vascular events increased with tamoxifen. With the P-1 results establishing tamoxifen as the standard of care for the primary chemoprevention of breast cancer in high-risk women, concern over the side effects of tamoxifen has prompted a continuing search for an agent that displays a more desirable efficacy/toxicity profile. Raloxifene, a second-generation SERM approved for the prevention of osteoporosis in postmenopausal women, displays antiestrogenic properties in the breast and possibly the endometrium, and estrogenic effects in the bone and on the lipid profile, suggesting it as a candidate for comparison with the chemopreventive standard, tamoxifen. Raloxifene will be compared to tamoxifen in an equivalency trial, the Study of Tamoxifen and Raloxifene (STAR) NSABP P-2, which began in July 1999 at almost 500 centers in North America. The plan is to randomize 22,000 postmenopausal women > or = 35 years of age at increased risk of breast cancer by Gail criteria to tamoxifen 20 mg/day or raloxifene 60 mg/day for 5 years. Study endpoints include invasive and noninvasive breast cancer, cardiovascular disease, endometrial cancer, bone fractures, and vascular events. PMID:11469927

Dunn, B K; Ford, L G

356

Photodynamic therapy and the treatment of neoplastic diseases of the head and neck: an update  

NASA Astrophysics Data System (ADS)

Forty-nine patients with neoplastic diseases of the larynx, oral cavity, pharynx and tracheobronchial tree have been treated with photodynamic therapy with follow-up to 40 months. Those patients with primary recurrent leukoplakia, carcinoma-in-situ, and T1 carcinomas obtained a complete response after one photodynamic therapy (PDT) treatment and remain free of disease. Eight patients with T2 and T3 carcinomas treated with PDT obtained a complete or partial response, but in all cases, the carcinomas recurred locally, many times with overlying normal mucosa. This is due to the inability to adequately deliver laser light to the depths of the tumor bed, despite aggressive use of interstitial implantation. PDT is highly effective for the curative treatment of early carcinomas (CIS, T1) of the head and neck. Further development of devices to measure and deliver light into the depths of a tumor bed are required prior to the use of PDT to effectively treat larger solid tumors of the head and neck.

Biel, Merrill A.

1994-07-01

357

Determination of the optical properties of vascular tissues: potential applications in vascular-targeting photodynamic therapy  

NASA Astrophysics Data System (ADS)

It has been proven that photodynamic therapy (PDT) is effective in treating various malignant and non-malignant diseases. In the treatment of certain non-malignant vascular diseases, such as wet age-related macular degeneration (AMD) and port wine stains (PWS), unlike in the treatment of malignant solid tumors, light irradiation usually starts immediately after the intravenous (IV) injection of photosensitizers while the photosensitizers is mainly circulating inside blood vessels. Under such vascular-targeting action mode, photoreactions between photosensitizers and light can selectively destruct the vascular tissues. Light distribution is complex so that it is important to understand the optical properties of targeted vessels and surrounding tissues. To better determine the optical properties of vascular tissues, we developed a tissue-simulating phantom and adopted frequency-domain measurement of phase difference. Absorption and reduced scattering coefficients in blood vessels were estimated and light distribution was simulated by the Monte Carlo method. These determinations are essential for the implication of better light dosimetry models in clinical photodynamic therapy and vascular-targeting PDT, in particular.

Tian, Yongbin; Chen, Ping; Lin, Lie; Huang, Zheng; Tang, Guoqing; Xu, Heping

2007-10-01

358

Applications of Natural Compounds in the Photodynamic Therapy of Skin Cancer.  

PubMed

Despite important progress in the early diagnosis and treatment, skin cancer is a major cause of death.  Photodynamic therapy (PDT) is a new therapeutic modality that is emerging as an important resource against malignant tumors. This strategy is based on the action of photosensitizers, i.e. of molecules which may accumulate preferentially inside tumor cells where they exert a cytotoxic effect upon excitation by light at appropriate wavelengths. Clinically, some forms of skin cancers and also some non-tumor pathologies are now treated with PDT. Several compounds with photosensitizing activity have been identified, and some of these molecules are commercially available. Many photoactive principles are natural compounds.  Numerous reviews in the last decade have focused on photodynamic therapy, its effects and applications, but less attention has been paid to plant extracts or molecules of natural origin studied for their phototoxic activity to date. This review critically examines the potential role of various plant extracts and naturally occurring compounds in the treatment of skin tumors. Both in vitro and in vivo effects of these agents, together with their known related cellular and molecular mechanisms, are presented and discussed. PMID:23531223

Marrelli, M; Menichini, G; Provenzano, E; Conforti, F

2013-03-15

359

Using delayed chemiluminescence as a photodynamic therapy dose metric in vivo  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is an important method to treat tumor. It is known that singlet oxygen (1O2) is the main factor mediating cytotoxicity in PDT. The effectiveness of a PDT treatment is directly linked to the 1O2 produced in the target. So to control the dose of 1O2 is very important. Although the luminescence from 1O2 can be detected and is suggested as an indicator for evaluating photodynamic therapy, the inherited disadvantages limit its potential for in vivo applications. We have previously reported that chemiluminescence (CL) can be used to detect 1O2 production in PDT and linked the signal to the cytotoxicity, but the irradiation of laser decrease the sensitivity of the detection in vivo. During PDT the high sensitivity probe, Fluoresceinyl Cypridina Luciferin Analog (FCLA), is used to monitor 1O2. In order to avoid the infection of irradiation light, the delayed CL of FCLA is used to indicate 1O2. After recording the delayed CL during PDT and scoring the skin of mice after PDT, the statistic analysis was done. The data shows a remarkable relationship between the score and the CL. the result suggests that the CL can be used as a dose metric in vivo in PDT.

Wei, Yanchun; Xing, Da; Chen, Qun

2007-05-01

360

Colloidal gold nanorings for improved photodynamic therapy through field-enhanced generation of reactive oxygen species  

NASA Astrophysics Data System (ADS)

Au nanostructures that exhibit strong localized surface plasmon resonance (SPR) have excellent potential for photo-medicine, among a host of other applications. Here, we report the synthesis and use of colloidal gold nanorings (GNRs) with potential for enhanced photodynamic therapy of cancer. The GNRs were fabricated via galvanic replacement reaction of sacrificial Co nanoparticles in gold salt solution with low molecular weight (Mw = 2,500) poly(vinylpyrrolidone) (PVP) as a stabilizing agent. The size and the opening of the GNRs were controlled by the size of the starting Co particles and the concentration of the gold salt. UV-Vis absorption measurements indicated the tunability of the SPR of the GNRs from 560 nm to 780 nm. MTT assay showed that GNRs were non-toxic and biocompatible when incubated with breast cancer cells as well as the healthy counterpart cells. GNRs conjugated with 5-aminolevulinic acid (5-ALA) photosensitizer precursor led to elevated formation of reactive oxygen species and improved efficacy of photodynamic therapy of breast cancer cells under light irradiation compared to 5-ALA alone. These results can be attributed to significantly enhance localized electromagnetic field of the GNRs.

Hu, Yue; Yang, Yamin; Wang, Hongjun; Du, Henry

2013-02-01

361

Antimicrobial photodynamic therapy with two photosensitizers on two oral streptococci: an in vitro study  

NASA Astrophysics Data System (ADS)

Periodontal diseases are caused by infection of tissues supporting the teeth due to complex aggregate of bacteria known as biofilm and firstly colonized by streptococci. The aim of this in vitro study was to evaluate the effect of Radachlorin® and Toluidine Blue O (TBO)-mediated photodynamic therapy (PDT) on the viability of two oral streptococci. Bacterial suspensions of Streptococcus mutans and Streptococcus sanguis were subjected to either TBO or Radachlorin®, Then exposed to two different diode laser light at energy densities of 3, 6 J/cm2 at 633 nm and 6, 12 J/cm2 at 662 nm, respectively. The control groups were subjected to laser light alone, photosensitizer alone or received neither photosensitizer nor light exposure. The suspensions were then spread over specific agar mediums and viable microorganisms were counted after overnight incubation aerobically at 37°C, 5% CO2 and then reported as colony forming unit. The results indicated that photosensitization by the energy density of 6 J/cm2 with Radachlorin® and both 3 and 6 J/cm2 with TBO caused significant reduction in bacterial colony formation ( p < 0.05). Radachlorin® and TBO-mediated photodynamic therapy seem to show excellent potential in significantly killing of two oral streptococci in vitro.

Vahabi, S.; Fekrazad, R.; Ayremlou, S.; Taheri, S.; Lizarelli, R. F. Z.; Kalhori, K. A. M.

2011-12-01

362

Biodistribution of indium 111-labeled dihematoporphyrin ether in papillomas and body tissues. Relevance to photodynamic therapy  

SciTech Connect

Hematoporphyrin derivative and its newly purified form, dihematoporphyrin ether, have been shown to localize selectively in malignant tissues and virally induced papillomas. Its use as a probe to distinguish tumors from normal tissues has been largely based on its fluorescence when activated by UV light. These findings are largely subjective, and a direct correlation to its use as a photosensitizing agent to selectively kill transformed cells when activated by an appropriate wavelength of light could not be made. The efficacy of dihematoporphyrin ether photodynamic therapy to selectively kill papillomavirus-transformed cells is based on the increased localization of dihematoporphyrin ether within these tissues as compared with normal tissues. Using cottontail rabbit papillomavirus, cutaneous papillomas were induced on the backs of Dutch belted rabbits. Dihematoporphyrin ether was labeled with indium 111 and intravenously injected into the rabbits. The animals were scanned twice daily for indium 111 activity on a large-field-of-view gamma camera. At 50 hours after injection, the rabbits were killed and papillomas, skin, and major organs collected for biodistribution studies. The results of this study and their relationship to dihematoporphyrin ether photodynamic therapy for the treatment of virally induced papilloma disease is discussed.

Shikowitz, M.J.; Galli, R.; Bandyopadhyay, D.; Hoory, S.

1989-07-01

363

Successful management of chronic multifocal Q fever Osteomyelitis with adjuvant interferon-gamma therapy.  

PubMed

We present a 3-year-old girl who had chronic recurrent multifocal osteomyelitis caused by Coxiella burnetii despite long-term dual antibiotic therapy. Excellent clinical response was achieved and sustained when immunomodulatory therapy with interferon-? was initiated. This is the case of a first child who was successfully treated with interferon-? as adjuvant therapy for chronic multifocal Q fever osteomyelitis. PMID:21372749

Neth, Olaf Werner; Falcon, Dolores; Peromingo, Estrella; Soledad Camacho, Maria; Rodríguez-Gallego, Carlos; Obando, Ignacio

2011-09-01

364

Adjuvant external beam radiation therapy with concurrent chemotherapy in the management of gallbladder carcinoma  

Microsoft Academic Search

Purpose: This study was performed to evaluate the outcome of patients with gallbladder cancer who received postoperative concurrent chemotherapy and radiation therapy.Methods and Materials: Curative resection followed by adjuvant combined modality therapy with external beam radiation therapy (EBRT) and chemotherapy was attempted in 21 consecutive gallbladder carcinoma (GBC) patients at the Mayo Clinic from 1985 through 1997. All patients received

John J Kresl; Steven E Schild; George T Henning; Leonard L Gunderson; John Donohue; Henry Pitot; Michael G Haddock; David Nagorney

2002-01-01

365

Photodynamic cancer therapy: fluorescence localization and light absorption spectra of chlorophyll-derived photosensitizers inside cancer cells  

Microsoft Academic Search

The first prerequisite for an optimum effect of photodynamic therapy with chlorophyll- derived photosensitizers is irradiation at the S1 absorption maximum in the red spectral region. This absorption maximum changes its position due to molecular association by 20 to 100 nm depending on the subcellular environment, and must be determined by direct absorption spectrometry in the region of subcellular sensitizer

Joerg G. Moser; Angelika C. Rueck; Hans-Joachim Schwarzmaier; Christel Westphal-Frosch

1992-01-01

366

Efficiency of Photodynamic Therapy in the Treatment of Diffuse Facial Viral Warts in an Immunosuppressed Patient: Towards a Gold Standard?  

PubMed Central

A 64-year-old man with a pulmonary transplant developed diffuse verrucae vulgares of the neck. After the failure of multiple cryotherapy treatments, 3 sessions of photodynamic therapy resulted in rapid therapeutic clinical success. This moderately painful and well-tolerated treatment is reproducible and can be very useful in treating papillomavirus infections in the immunosuppressed patient.

Caucanas, M.; Gillard, P.; Vanhooteghem, O.

2010-01-01

367

Evaluation of transurethral and transperineal tin ethyl etiopurpurin-photodynamic therapy on the canine prostate one week after drug injection  

Microsoft Academic Search

We have been investigating the potential applicability of photodynamic therapy for the treatment of benign and malignant disease of the prostate. Both transurethral and transperineal approaches to the delivery of light to the tin ethyl etiopurpurin sensitized canine prostate have been studied. Pharmacologic studies were performed and suggested that delaying light treatment for 7 days after drug administration would maximize

Steven H. Selman; Rick W. Keck; Sandy Kondo; Detlef Albrecht

1999-01-01

368

Long-term results after photodynamic therapy with verteporfin for choroidal neovascularizations secondary to inflammatory chorioretinal diseases  

Microsoft Academic Search

Background To evaluate the safety and the long-term effect on visual acuity of photodynamic therapy (PDT) for sub- and juxtafoveal choroidal neovascularizations (CNV) secondary to inflammatory conditions. Methods In a prospective pilot study, 19 patients with CNV due to inflammatory conditions underwent PDT treatment with verteporfin with standard parameters. Regular follow-up was carried out every 3 months with ETDRS visual

Joachim Wachtlin; Heinrich Heimann; Tim Behme; Michael H. Foerster

2003-01-01

369

Study of the stabilization of zinc phthalocyanine in sol-gel TiO 2 for photodynamic therapy applications  

Microsoft Academic Search

Photodynamic therapy (PDT) has emerged as an alternative and promising noninvasive treatment for cancer. It is a two-step procedure that uses a combination of molecular oxygen, visible light, and photosensitizer (PS) agents; phthalocyanine (Pc) was supported over titanium oxide but has not yet been used for cell inactivation. Zinc phthalocyanine (ZnPc) molecules were incorporated into the porous network of titanium

Tessy Lopez; Ema Ortiz; Mayra Alvarez; Juan Navarrete; Jose A. Odriozola; Fernando Martinez-Ortega; Edgar A. Páez-Mozo; Patricia Escobar; Karla A. Espinoza; Ignacio A. Rivero

2010-01-01

370

In vivo small animal imaging for early assessment of therapeutic efficacy of photodynamic therapy for prostate cancer  

Microsoft Academic Search

We are developing in vivo small animal imaging techniques that can measure early effects of photodynamic therapy (PDT) for prostate cancer. PDT is an emerging therapeutic modality that continues to show promise in the treatment of cancer. At our institution, a new second-generation photosensitizing drug, the silicon phthalocyanine Pc 4, has been developed and evaluated at the Case Comprehensive Cancer

Baowei Fei; Hesheng Wang; Xiang Chen; Joseph Meyers; John Mulvilhill; Denise Feyes; Nancy Edgehouse; Jeffrey L. Duerk; Thomas G. Pretlow; Nancy L. Oleinick

2007-01-01

371

Routine experimental system for defining conditions used in photodynamic therapy and fluorescence photodetection of (non-) neoplastic epithelia  

Microsoft Academic Search

A common method to induce enhanced short-term endogenous porphyrin synthesis and accumulation in cell is the topical, systemic application of 5-aminolevulinic acid or one of its derivatives. This circumvents the intravenous administration of photosensitizers normally used for photodynamic therapy (PDT) of fluorescence photodetection. However, in the majority of potential medical indications, optimal conditions with respect to the porphyrin precursor or

Norbert Lange; Laurent Vaucher; Alexandre Marti; Anne-Lise Etter; Patrick Gerber; Hubert van den Bergh; Patrice Jichlinski; Pavel Kucera

2001-01-01

372

Local delivery of photosensitizing drugs in arteries: a novel approach to photodynamic therapy for the prevention of intimal hyperplasia  

Microsoft Academic Search

The long-term benefit of coronary or peripheral vascular interventions is limited by restenosis, due to intimal hyperplasia (IH). Photodynamic therapy (PDT) with systematic delivery of the photosensitizing drug, performed either at the time or shortly after vascular injury, has been demonstrated to effectively inhibit the development of experimental IH. However, in order to deliver large quantities of the photosensitizer, but

Farzin Adili; Randolph G. van Eps; Glenn M. Lamuraglia

1995-01-01

373

A laser-spectroscopy system for fluorescent diagnostics and photodynamic therapy of diseases of eye retina and choroid  

SciTech Connect

A laser-spectroscopy system for the fluorescent diagnostics and photodynamic therapy of pathologic eye-fundus changes combined with the use of the Photosens compound is developed. The system is tested on experimental animals (mice and rabbits). (laser biology and medicine)

Meerovich, G A; Shevchik, S A; Loshchenov, M V [Natural Science Center, A.M. Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Budzinskaya, M V; Ermakova, N A [Helmholtz Moscow Research Institute of Eye Diseases, Moscow (Russian Federation); Kharnas, S S [I.M. Sechenov Moscow Academy of Medicine, Moscow (Russian Federation)

2002-11-30

374

Adjuvant therapy in high-risk early endometrial carcinoma: a retrospective analysis of 46 cases  

PubMed Central

Objective We assessed the prognostic factors and the efficacy of adjuvant therapy and reviewed randomized studies carried out on patients receiving adjuvant therapy with early endometrial carcinoma. Methods One hundred and five patients that received primary surgical treatment for stage IB, IC and II endometrial cancer were enrolled in this study. The clinical outcomes were compared among the patients with variable prognostic factors and adjuvant treatments. Results One hundred and five patients fulfilled the eligibility criteria and 46 patients (43.8%) underwent adjuvant therapy. Disease recurrence occurred in nine patients within a median time of 24 months. Cervical involvement was an independent prognostic factor for the disease-free survival rates. Eight of 16 patients with FIGO stage II disease received adjuvant chemotherapy consisting of cisplatin and etoposide (or cyclophosphamide) or combined chemoradiation. The 5-year disease-free survival rate for these patients was 87.5%, a value significantly higher than for patients that received radiation therapy alone (30%). Conclusion Adjuvant chemotherapy or combination chemo-radiotherapy might be superior to radiation therapy alone in high-risk early endometrial cancer patients.

Kim, Jin Hwi; Lee, Sung Jong; Bae, Jeong Hoon; Lee, Sung Ha; Bae, Seog Nyeon; Namkoong, Sung Eun

2008-01-01

375

Chondrodermatitis nodularis chronica helicis and photodynamic therapy: a new therapeutic option?  

PubMed

Chondrodermatitis nodularis chronica helicis (CNCH) is a fairly frequent disorder of unknown etiology. Although the elective therapy is surgery, local application of topical steroids, antibiotic ointments, intralesional injection of collagen, cryotherapy, curettage followed by diathermy, and CO(2) laser treatment have also been proposed. The aim of the study was to test the utility of photodynamic therapy (PDT) for CNCH. Two patients with painful CNCH underwent PDT with a 635 nm light source for 20 minutes (70 J/cm(2) ) after application of cream containing 20% 5-aminolevulinic acid (5-ALA) and occlusion for 3 hours. The lesions decreased considerably in size and pain ceased within a few weeks. The results suggest that this method can be useful for treating CNCH, especially in patients with contraindications for surgery. PMID:21276169

Pellegrino, M; Taddeucci, P; Mei, S; Peccianti, C; Fimiani, M

376

A Pilot Trial of Vascular-Targeted Photodynamic Therapy in Renal Tissue  

PubMed Central

Purpose Vascular-targeted photodynamic therapy (VTP) represents the newest generation of photodynamic therapy and a new paradigm for minimally-invasive ablative therapy. We report on a pilot trial of VTP to evaluate the effect on porcine renal tissue. Materials and Methods Pigs underwent continuous infusion of WST-09 and concurrent illumination with interstitial laser at a wavelength of 763 nm to the lower pole of the kidney. Drug doses were 0.5–1.0mg/kg and light doses 100–200 Joules. Nuclear renography was performed on POD 5. On POD 7 arteriography, pyelography, computed tomography of the abdomen, and necropsy was performed. Results Four of seven animals completed therapy and all evaluations. Three animals died, 1 from surgical complications, and 2 due to an anaphylactoid reaction to the cremophor solvent in the compound. All kidneys in the surviving animals functioned on nuclear renography. Renal function remained unchanged. No lesions or urine leaks were visible on imaging. On necropsy lesion sizes ranged from 5×4×3mm to 7×7×14mm, depending on drug/light dose. Histology showed a distinct demarcation between the treated zone and surrounding parenchyma at the higher doses. The lesions were well-demarcated, with necrotic tubules, glomerular fibrinoid necrosis, thrombosis of capillary loops, interstitial hemorrhage, and lymphocytic infiltrates. Conclusions Significant tissue effect with some necrosis was seen at these low drug/light combinations. This study provides the initial proof of principle that justifies further preclinical investigation of VTP for treatment of renal tumors. A newer water-based formulation should reduce the incidence of reactions in swine. This newer formulation will allow for further safe investigation of this novel treatment paradigm.

Matin, Surena F.; Tinkey, Peggy T.; Borne, Agatha T.; Stephens, L. Clifton; Sherz, Avigdor; Swanson, David A.

2009-01-01

377

Two-dimensional ultrasound image matching system for photodynamic therapy  

NASA Astrophysics Data System (ADS)

Two-dimensional (2D) ultrasound imaging is commonly used for diagnosis in a variety of medical fields. However, there are several drawbacks of conventional 2D-ultrasound imaging. These include prostate or transducer movement that produces sets of different images that are difficult to interpret. Also during patient's reexamination correspondence between sets of images before reexamination and after is difficult to establish. This can be described as a problem of correlation between two sets of images: the first created before distortion or examination, the second one after. We propose a method to register 2D ultrasound volumes based on external markers introduced in the prostate. The metal balls are inserted in the prostate at three distinct locations in the prostate. These appear as bright dots in the ultrasound field, serve as reference points, are then outlined through a user-interactive program from two sets of images. Then, the computer program rotates and translates till they match respectively, and displays the mapped points with their corresponding location. Based on this idea we developed an image-guided system for PDT that require high-precision placement of implants. In the planning stage, the system performs an automatic acquisition of 2D transrectal ultrasound images that will ultimately be used to construct the treatment plan. At the time of the therapy, new sets of ultrasound images are acquired and a match is established between the virtual world and the patient's real world with the aid of manually introduced markers and image matching algorithms.

Zaim, Amjad; Keck, Rick W.; Selman, Steven H.; Jankun, Jerzy

2001-05-01

378

Sequential hormonal therapy for metastatic breast cancer after adjuvant tamoxifen or anastrozole.  

PubMed

The use of adjuvant endocrine therapy in the treatment of hormone receptor-positive, early breast cancer has become important in both pre- and postmenopausal women. Tamoxifen has been the principal adjuvant hormonal therapy in pre- and postmenopausal women with hormone receptor-positive breast cancer for nearly 20 years. Recent data in premenopausal women suggest benefit from ovarian ablation with or without tamoxifen. Early results from the 'Arimidex', Tamoxifen, Alone or in Combination (ATAC) trial have demonstrated that the third-generation, selective aromatase inhibitor (AI) anastrozole ('Arimidex') is a suitable alternative adjuvant therapy for postmenopausal women with hormone receptor-positive disease. After recurrence or relapse on adjuvant endocrine therapy, responses to the sequential use of additional endocrine agents are common. The increase in the number of options now available for adjuvant therapy will have important implications for the selection of the optimal sequence of endocrine agents in the treatment of recurrent breast cancer. Menopausal status is an important factor in determining the endocrine therapy that a patient receives. For premenopausal women, tamoxifen and/or a luteinizing hormone-releasing hormone agonist such as goserelin ('Zoladex') are both options for adjuvant endocrine treatment. After progression on adjuvant and first-line tamoxifen, ovarian ablation is an appropriate second-line therapy. For premenopausal women who have undergone ovarian ablation, the use of third-line therapy with an AI becomes possible. For postmenopausal women, a wide choice of endocrine treatment options is available and an optimal sequence has yet to be determined. Options for first-line therapy of metastatic disease include an AI for women who have received adjuvant tamoxifen or tamoxifen for patients who have received adjuvant anastrozole. In addition, data suggest that fulvestrant ('Faslodex'), a novel estrogen receptor (ER) antagonist that downregulates the ER protein and has no known agonist effects, is a promising therapeutic option that has shown efficacy in the treatment of postmenopausal women with advanced breast cancer. Other agents that may be used in the sequence include the steroidal AI exemestane and the progestin megestrol acetate. The widening range of adjuvant endocrine options therefore represents an opportunity to prolong patient benefits in the treatment of hormone receptor-positive breast cancer, and will require the further refinement of the optimal sequence of endocrine agents for the treatment of recurrent breast cancer. PMID:14535531

Carlson, Robert W; Henderson, I Craig

2003-01-01

379

Effect of photodynamic therapy using benzoporphyrin derivative on the cutaneous immune response  

NASA Astrophysics Data System (ADS)

In this study, the effect of transdermal photodynamic therapy (PDT) using benzoporphyrin derivative monoacid ring A (BPD) on the development of the immunologically mediated contact hypersensitivity (CHS) response against the hapten dinitrofluorobenzene (DNFB) and on the duration of skin allograft acceptance has been evaluated. In the CHS model it was found that the treatment of hairless strain mice with whole-body transdermal PDT using BPD (i mg/kg) and LED light (15 J/cm2) resulted in a profound suppression of the CHS reaction if treatment was applied either 48 or 24 hours prior or up to 72 hours after sensitization of abdominal skin with DNFB. Less inhibition of the CHS response was observed if PDT was given one day before the ear challenge with DNFB which was applied 5 days following the initial DNFB sensitization. However, DNFB-exposed, PDT-treated mice retained the capacity to respond maximally to the unrelated contact sensitizer oxazolone. These results are consistent with other models of experimentally induced immune tolerance. allogeneic skin graft studies demonstrated that pretreatment of skin with BPD and light, at levels that did not cause significant tissue damage, significantly enhanced the length of engraftment. Using a separate protocol, photodynamic treatment of recipient mice at various times after transplant had no significant effect on allograft acceptance. Irradiation of skin in the presence of BPD may significantly inhibit the initiation of certain immunological responses within these tissues.

Simkin, Guillermo; Obochi, Modestus; Hunt, David W.; Chan, Agnes H.; Levy, Julia G.

1995-05-01

380

Hetergeneous tumour response to photodynamic therapy assessed by in vivo localised 31P NMR spectroscopy.  

PubMed Central

Photodynamic therapy (PDT) is efficacious in the treatment of small malignant lesions when all cells in the tumour receive sufficient drug, oxygen and light to induce a photodynamic effect capable of complete cytotoxicity. In large tumours, only partial effectiveness is observed presumably because of insufficient light penetration into the tissue. The heterogeneity of the metabolic response in mammary tumours following PDT has been followed in vivo using localised phosphorus NMR spectroscopy. Alterations in nucleoside triphosphates (NTP), inorganic phosphate (Pi) and pH within localised regions of the tumour were monitored over 24-48 h following PDT irradiation of the tumour. Reduction of NTP and increases in Pi were observed at 4-6 h after PDT irradiation in all regions of treated tumours. The uppermost regions of the tumours (those nearest the skin surface and exposed to the greatest light fluence) displayed the greatest and most prolonged reduction of NTP and concomitant increase in Pi resulting in necrosis. The metabolite concentrations in tumour regions located towards the base of the tumour returned a near pre-treatment levels by 24-48 h after irradiation. The ability to follow heterogeneous metabolic responses in situ provides one means to assess the degree of metabolic inhibition which subsequently leads to tumour necrosis. Images Figure 4

Ceckler, T. L.; Gibson, S. L.; Kennedy, S. D.; Hill, R.; Bryant, R. G.

1991-01-01

381

5-aminolaevulinic acid for fluorescence diagnosis and photodynamic therapy of bronchial cancer: a case report  

NASA Astrophysics Data System (ADS)

Five-aminolaevulinic acid (ALA) was applied orally and by aerosol inhalation to one patient in order to check the feasibility of photodynamic therapy (PDT) and photodynamic fluorescence diagnosis (PDD) of lung cancer. For PDD, ALA was given by inhalation using a conventional jet nebulizer. Protoporphyrin IX (PP IX)-fluorescence in the bronchial mucosa and the tumor was assessed visually and by spectroscopy using an optical multichannel analyzer. At a second session ALA was given orally and PDD as well as PDT were performed. The therapeutic effect on the tumor was controlled by bronchoscopy 5 and 12 weeks after PDT. Inhalative and oral application of ALA were both well tolerated. No adverse effects were observed. PP IX- fluorescence could be easily detected 3 h after ALA administered by inhalation or 5 h after ALA orally. Fluorescence ratio between tumor and normal tissues was better after the oral administration of ALA. Five and twelve weeks after PDT, marked reduction of tumor volume and recanalization of the left upper lobe were found.

Gamarra, Fernando; Baumgartner, Reinhold; Stepp, Herbert G.; Rick, Kai; Leberig, A.; Huber, Rudolf M.

1994-10-01

382

5-aminolaevulinic acid for fluorescence diagnosis and photodynamic therapy of bronchial cancer: a case report  

NASA Astrophysics Data System (ADS)

Five-aminolaevulinic acid (ALA) was applied orally and by aerosol inhalation to one patient in order to check the feasibility of photodynamic therapy (PDT) and photodynamic fluorescence diagnosis (PDD) of lung cancer. For PDD, ALA was given by inhalation using a conventional jet nebulizer. Protoporphyrin IX (PP IX)-fluorescence in the bronchial mucosa and the tumor was assessed visually and by spectroscopy using an optical multichannel analyzer. At a second session ALA was given orally and PDD as well as PDT were performed. The therapeutic effect on the tumor was controlled by bronchoscopy 5 and 12 weeks after PDT. Inhalative and oral application of ALA were both well tolerated. No adverse effects were observed. PP IX- fluorescence could be easily detected 3 h after ALA administered by inhalation or 5 h after ALA orally. Fluorescence ratio between tumor and normal tissues was better after the oral administration of ALA. Five and twelve weeks after PDT, marked reduction of tumor volume and recanalization of the left upper lobe were found.

Gamarra, Fernando; Baumgartner, Reinhold; Stepp, Herbert G.; Rick, Kai; Leberig, A.; Huber, Rudolf M.

1995-03-01

383

Topical delivery of a preformed photosensitizer for photodynamic therapy of cutaneous lesions  

NASA Astrophysics Data System (ADS)

Photosensitizers for photodynamic therapy (PDT) are most commonly delivered to patients or experimental animals via intravenous injection. After initial distribution throughout the body, there can be some preferential accumulation within tumors or other abnormal tissue in comparison to the surrounding normal tissue. In contrast, the photosensitizer precursor, 5-aminolevulinic acid (ALA) or one of its esters, is routinely administered topically, and more specifically, to target skin lesions. Following metabolic conversion to protoporphyrin IX, the target area is photoilluminated, limiting peripheral damage and targeting the effective agent to the desired region. However, not all skin lesions are responsive to ALA-PDT. Topical administration of fully formed photosensitizers is less common but is receiving increased attention, and some notable advances with selected approved and experimental photosensitizers have been published. Our team has examined topical administration of the phthalocyanine photosensitizer Pc 4 to mammalian (human, mouse, pig) skin. Pc 4 in a desired formulation and concentration was applied to the skin surface at a rate of 5-10 ?L/cm2 and kept under occlusion. After various times, skin biopsies were examined by confocal microscopy, and fluorescence within regions of interest was quantified. Early after application, images show the majority of the Pc 4 fluorescence within the stratum corneum and upper epidermis. As a function of time and concentration, penetration of Pc 4 across the stratum corneum and into the epidermis and dermis was observed. The data indicate that Pc 4 can be delivered to skin for photodynamic activation and treatment of skin pathologies.

Oleinick, Nancy L.; Kenney, Malcolm E.; Lam, Minh; McCormick, Thomas; Cooper, Kevin D.; Baron, Elma D.

2012-02-01

384

Whole bladder wall photodynamic therapy of transitional cell carcinoma rat bladder tumors using intravesically administered hypericin.  

PubMed

Whole-bladder wall photodynamic therapy (PDT) is a promising treatment for carcinoma in situ (CIS) and diffuse premalignant changes of the bladder. After the results of our clinical studies showing that intravesical hypericin selectively accumulates in superficial bladder tumors, we investigated the hypericin-PDT efficacy in an AY-27 orthotopic transitional cell carcinoma rat bladder tumor model. After the instillation of hypericin (30 microM, 2 hr) in the bladder, tumors were irradiated (25-50 mW/cm 6-48 J/cm(2)) using 595 nm laser light. Data demonstrate that light doses of 12-48 J/cm(2) resulted in selective PDT-induced urothelial tumor damage without damaging detrusor musculature. Histological assessment of bladder sections 2 days after PDT showed tumor destruction, with tumor cells shrinking and detaching from the bladder wall. There were tumor regrowth 1-3 weeks after treatment. The in vivo/in vitro clonogenic assay results revealed up to 98% of tumor cell kill by hypericin PDT. In conclusion, hypericin PDT can be used to safely induce a selective urothelial tumor damage without damaging detrusor musculature, when optimum hypericin concentration and light fluences are used. A small percentage (2-5%) of tumor cells that survive the photodynamic treatment resulting in tumor regrowth after a prolonged period of time is likely due to oxygen depletion during light irradiation. PMID:14506748

Kamuhabwa, Appolinary A R; Roskams, Tania; D'Hallewin, Marie-Ange; Baert, Luc; Van Poppel, Hein; de Witte, Peter A M

2003-11-10

385

Photodynamic therapy is potentiated by Co60 and intratumoral injection of hematoporphyrin derivative.  

PubMed

Hematoporphyrin derivative injected directly into a subcutaneous rat glioma resulted in a significant greater tumor growth inhibition than hematoporphyrin derivative injected parenterally upon stimulation by light, Co60 or by combination of the above. The photodynamic effect was analyzed in an in vivo and in an in vitro clonogenic assay. The directly injected hematoporphyrin derivative without external activation inhibited tumor growth to 34%. Light and directly injected HPD inhibited tumor growth to 3%, whereas 4, 8 and 16 Gy of Co60 produced a growth inhibition to 11%, 0.05% and 0.00% respectively. This cytotoxic effect of the ionizing radiation is further potentiated by the addition of light, resulting in a growth inhibition to 0.1%, 0.00% and 0.00% respectively for the three corresponding radiation doses. The direct intratumoral injection of HPD minimizes the side effects and increases the effect of the photodynamic therapy as compared to the parenterally administered HPD. This direct injection modality could be of potential value in the treatment of human gliomas or other tumors. PMID:2976084

Kostron, H; Swartz, M R; Martuza, R L

1988-09-01

386

Induction of immune cell infiltration into murine SCCVII tumour by photofrin-based photodynamic therapy.  

PubMed Central

Cellular populations in the squamous cell carcinoma SCCVII, growing in C3H/HeN mice given Photofrin, were examined at various time intervals during the photodynamic light treatment and up to 8 h later. Cell populations present within excised tumours were identified by monoclonal antibodies directed against cell type-specific membrane markers using a combination of the indirect immunoperoxidase and Wright staining or by flow cytometry. Photofrin-based photodynamic therapy (PDT) induced dramatic changes in the level of different cellular populations contained in the treated tumour. The most pronounced was a rapid increase in the content of neutrophils, which increased 200-fold within 5 min after the initiation of light treatment. This was followed immediately by an increase in the levels of mast cells, while another type of myeloid cells, most likely monocytes, invaded the tumour between 0 and 2 h after PDT. The examination of cytolysis of in vitro cultured SCCVII tumour cells mediated by macrophages harvested from the SCCVII tumour revealed a pronounced increase in the tumoricidal activity of tumour-associated macrophages isolated at 2 h post PDT. It seems, therefore, that the PDT-induced acute inflammatory infiltration of myeloid cells into the treated tumour is associated with functional activation of immune cells.

Krosl, G.; Korbelik, M.; Dougherty, G. J.

1995-01-01

387

Nanoparticles improve biological functions of phthalocyanine photosensitizers used for photodynamic therapy.  

PubMed

Photodynamic therapy (PDT) is a new technology using photodynamic effect for disease diagnosis and treatment. It is a two-step technique involving the uptake of a photosensitizer by cancer tissue followed by light irradiation that excites the photosensitizer to produce highly reactive oxygen species, the latter execute apoptosis of cancerous cells. As a second-generation of photosensitizers, phthalocyanine demonstrates higher absorption in the 650-800 nm range and short tissue accumulation compared to their first generation. However, many potent phthalocyanine photosensitizers are hydrophobic and poorly water-soluble, which limit their therapeutic applications. As a result, advanced delivery systems and different strategies are called for to improve the effectiveness of PDT. Facts have proved that using nanoparticles as carries of photosensitizers is a very promising route. Nanoparticles have the potentials to increase photosensitizers' aqueous solubility, bioavailability and stability, and deliver photosensitizers to the target tissues. This article reviewed the commonly-used nanoparticles, including colloid gold, quantum dots, paramagnetic nanoparticles, silica-based materials, polymer-based nanoparticles, as potential delivery systems for phthalocyanine photosensitizers, and summarized the improved biological functions of phthalocyanine photosensitizers in PDT. PMID:22380016

Jia, Xiao; Jia, Lee

2012-10-01

388

Survival analysis of women with breast cancer under adjuvant therapy in South India.  

PubMed

While there has been much research in identifying risk factors and prognostic factor for breast cancer for breast cancer survival, the research specific to South Indian population is limited: Most of the association studies between breast cancer and risk factor have been widely studied in developed countries. This study attempts to explore the survival experience of breast cancer patients treated under adjuvant and neo-adjuvant therapy. The data were obtained from a Government Cancer Hospital, Tamil Nadu, South India and included 522 women diagnosed and treated with adjuvant and neo-adjuvant therapy between January 2000 to December 2008 and follow up to May 2010. The survival experiences under two treatments are presented using Kaplan-Meier survival curves. The important prognostic variables for response to treatment survival were identified using Cox regression with and without time-dependent covariates. Of the 522 cases, 248(47.5%) were of stage 2 (A and B), 249 (47.7%) were of stage 3 (A and B). About 90% received neo-adjuvant therapy. About 94% of the patients had response to treatment. The Cox model showed that apart from the chemotherapy, number of children, child birth status and stage 3B and 4 turn out to be significant predictors for response to treatment survival. This is the first study to evaluate adjuvant therapy effects under hospital setup in South India. The results show that response to treatment survival is related poor in advanced stage patients under treatment. PMID:22126494

Venkatesan, P; Raman, T T; Ponnuraja, C

2011-01-01

389

Use of neoadjuvant data to design adjuvant endocrine therapy trials for breast cancer  

PubMed Central

Mature outcomes from adjuvant endocrine therapy trials in estrogen receptor-positive breast cancer have enabled comparisons with neoadjuvant clinical trials that have parallel randomizations of treatment in terms of the response of disseminated disease versus the local response within the breast. Imprecise end points, such as ‘clinical response’, have produced inconsistent results regarding the relationship between neoadjuvant and adjuvant endocrine therapy outcomes. However, the proliferation marker Ki-67, measured during neoadjuvant treatment, has predicted accurately and consistently the results of much larger studies in the adjuvant setting. In this Review, we summarize these trials and discuss the implications for the design of future adjuvant endocrine therapy trials. We conclude that there is sufficient evidence supporting the view that the degree of Ki-67 suppression is a reliable short-term surrogate for the adjuvant potential of endocrine drugs, at least in postmenopausal women. We propose that adjuvant endocrine therapy trials should only be conducted once adequately-powered neoadjuvant studies have indicated superior Ki-67 suppression in patients receiving experimental endocrine treatment versus the standard treatment.

Goncalves, Rodrigo; Ma, Cynthia; Luo, Jingqin; Suman, Vera; Ellis, Matthew James

2012-01-01

390

Anti-tumor immune response after photodynamic therapy  

NASA Astrophysics Data System (ADS)

Anti-tumor immunity is stimulated after PDT due a number of factors including: the acute inflammatory response caused by PDT, release of antigens from PDT-damaged tumor cells, priming of the adaptive immune system to recognize tumor-associated antigens (TAA), and induction of heat-shock proteins. The induction of specific CD8+ T-lymphocyte cells that recognize major histocompatibility complex class I (MHC-I) restricted epitopes of TAAs is a highly desirable goal in cancer therapy as it would allow the treatment of tumors that may have already metastasized. The PDT killed tumor cells may be phagocytosed by dendritic cells (DC) that then migrate to draining lymph nodes and prime naïve T-cells that recognize TAA epitopes. We have carried out in vivo PDT with a BPD-mediated vascular regimen using a pair of BALB/c mouse colon carcinomas: CT26 wild type expressing the naturally occurring retroviral antigen gp70 and CT26.CL25 additionally expressing beta-galactosidase (b-gal) as a model tumor rejection antigen. PDT of CT26.CL25 cured 100% of tumors but none of the CT26WT tumors (all recurred). Cured CT26.CL25 mice were resistant to rechallenge. Moreover mice with two bilateral CT26.CL25 tumors that had only one treated with PDT demonstrated spontaneous regression of 70% of untreated contralateral tumors. T-lymphocytes were isolated from lymph nodes of PDT cured mice that recognized a particular peptide specific to b-gal antigen. T-lymphocytes from LN were able to kill CT26.CL25 target cells in vitro but not CT26WT cells as shown by a chromium release assay. CT26.CL25 tumors treated with PDT and removed five days later had higher levels of Th1 cytokines than CT26 WT tumors showing a higher level of immune response. When mice bearing CT26WT tumors were treated with a regimen of low dose cyclophosphamide (CY) 2 days before, PDT led to 100% of cures (versus 0% without CY) and resistance to rechallenge. Low dose CY is thought to deplete regulatory T-cells (Treg, CD4+CD25+foxp3+) and potentiate immune response after PDT in the case of tumors that express self-antigens. These data suggest that PDT alone will stimulate a strong immune response when tumors express a robust antigen, and in cases where tumors express a self-antigen, T-reg depletion can unmask the immune response after PDT.

Mroz, Pawel; Castano, Ana P.; Wu, Mei X.; Kung, Andrew L.; Hamblin, Michael R.

2009-06-01

391

Regulation of miRNA Expression by Low-Level Laser Therapy (LLLT) and Photodynamic Therapy (PDT)  

PubMed Central

Applications of laser therapy, including low-level laser therapy (LLLT), phototherapy and photodynamic therapy (PDT), have been proven to be beneficial and relatively less invasive therapeutic modalities for numerous diseases and disease conditions. Using specific types of laser irradiation, specific cellular activities can be induced. Because multiple cellular signaling cascades are simultaneously activated in cells exposed to lasers, understanding the molecular responses within cells will aid in the development of laser therapies. In order to understand in detail the molecular mechanisms of LLLT and PDT-related responses, it will be useful to characterize the specific expression of miRNAs and proteins. Such analyses will provide an important source for new applications of laser therapy, as well as for the development of individualized treatments. Although several miRNAs should be up- or down-regulated upon stimulation by LLLT, phototherapy and PDT, very few published studies address the effect of laser therapy on miRNA expression. In this review, we focus on LLLT, phototherapy and PDT as representative laser therapies and discuss the effects of these therapies on miRNA expression.

Kushibiki, Toshihiro; Hirasawa, Takeshi; Okawa, Shinpei; Ishihara, Miya

2013-01-01

392

Regulation of miRNA Expression by Low-Level Laser Therapy (LLLT) and Photodynamic Therapy (PDT).  

PubMed

Applications of laser therapy, including low-level laser therapy (LLLT), phototherapy and photodynamic therapy (PDT), have been proven to be beneficial and relatively less invasive therapeutic modalities for numerous diseases and disease conditions. Using specific types of laser irradiation, specific cellular activities can be induced. Because multiple cellular signaling cascades are simultaneously activated in cells exposed to lasers, understanding the molecular responses within cells will aid in the development of laser therapies. In order to understand in detail the molecular mechanisms of LLLT and PDT-related responses, it will be useful to characterize the specific expression of miRNAs and proteins. Such analyses will provide an important source for new applications of laser therapy, as well as for the development of individualized treatments. Although several miRNAs should be up- or down-regulated upon stimulation by LLLT, phototherapy and PDT, very few published studies address the effect of laser therapy on miRNA expression. In this review, we focus on LLLT, phototherapy and PDT as representative laser therapies and discuss the effects of these therapies on miRNA expression. PMID:23807510

Kushibiki, Toshihiro; Hirasawa, Takeshi; Okawa, Shinpei; Ishihara, Miya

2013-06-27

393

Comparison of photodynamic therapy with different excitation wavelengths using a dynamic model of aminolevulinic acid-photodynamic therapy of human skin.  

PubMed

Different wavelength light sources are used in photodynamic therapy (PDT) of the skin to treat different conditions. Clinical studies show inconsistent results for the effectiveness of aminolevulinic acid (ALA)-PDT performed at different wavelengths. In order to understand the effect of treatment wavelength, a theoretical study was performed to calculate time-resolved depth-dependent distributions of PDT components including ground-state oxygen, sensitizer, and reacted singlet oxygen for different treatment wavelengths (405, 523, and 633 nm) using a numerical model of ALA-PDT of human skin. This model incorporates clinically relevant features of the PDT process including light attenuation, photobleaching, oxygen consumption, and diffusion, as well as tissue perfusion. The calculations show that the distributions of these quantities are almost independent of the treatment wavelength to a depth of about 1 mm. In this surface region, PDT-induced hypoxia is the dominant process. At greater depths, the production of singlet -oxygen is governed by the penetration of the treatment light. Two noninvasive PDT dosimetry approaches: the cumulative singlet oxygen luminescence (CSOL) and the fractional fluorescence bleaching metric, were investigated and compared for all three wavelengths. Although CSOL was more robust, both metrics provided correlations with the singlet oxygen dose in the upper dermis that were almost independent of treatment wavelength. This relationship breaks down at greater depths because light penetration depends on wavelength. PMID:23224203

Liu, Baochang; Farrell, Thomas J; Patterson, Michael S

2012-08-01

394

Tumor-targeting hyaluronic acid nanoparticles for photodynamic imaging and therapy.  

PubMed

Tumor-targeted imaging and therapy have been the challenging issue in the clinical field. Herein, we report tumor-targeting hyaluronic acid nanoparticles (HANPs) as the carrier of the hydrophobic photosensitizer, chlorin e6 (Ce6) for simultaneous photodynamic imaging and therapy. First, self-assembled HANPs were synthesized by chemical conjugation of aminated 5?-cholanic acid, polyethylene glycol (PEG), and black hole quencher3 (BHQ3) to the HA polymers. Second, Ce6 was readily loaded into the HANPs by a simple dialysis method resulting in Ce6-loaded hyaluronic acid nanoparticles (Ce6-HANPs), wherein in the loading efficiency of Ce6 was higher than 80%. The resulting Ce6-HANPs showed stable nano-structure in aqueous condition and rapid uptake into tumor cells. In particular Ce6-HANPs were rapidly degraded by hyaluronidases abundant in cytosol of tumor cells, which may enable intracellular release of Ce6 at the tumor tissue. After an intravenous injection into the tumor-bearing mice, Ce6-HANPs could efficiently reach the tumor tissue via the passive targeting mechanism and specifically enter tumor cells through the receptor-mediated endocytosis based on the interactions between HA of nanoparticles and CD44, the HA receptor on the surface of tumor cells. Upon laser irradiation, Ce6 which was released from the nanoparticles could generate fluorescence and singlet oxygen inside tumor cells, resulting in effective suppression of tumor growth. Overall, it was demonstrated that Ce6-HANPs could be successfully applied to in vivo photodynamic tumor imaging and therapy simultaneously. PMID:22364699

Yoon, Hong Yeol; Koo, Heebeom; Choi, Ki Young; Lee, So Jin; Kim, Kwangmeyung; Kwon, Ick Chan; Leary, James F; Park, Kinam; Yuk, Soon Hong; Park, Jae Hyung; Choi, Kuiwon

2012-02-24

395

Photodynamic Therapy Combined with Intravitreal Injection of Vascu lar Endothelial Growth Factor Antibody for Polypoidal Choroidal Vasculopathy  

Microsoft Academic Search

Background\\/Aims: To evaluate the efficacy of photodynamic therapy (PDT) combined with intravitreal injection of anti-vascular-endothelial-growth-factor (anti-VEGF) antibody in patients with polypoidal choroidal vasculopathy (PCV). Methods: Twenty-two eyes of 22 patients with PCV followed for 12 months after combination therapy with PDT and anti-VEGF were retrospectively reviewed. Patients received intravitreal anti-VEGF (1.25 mg bevacizumab or 0.5 mg ranibizumab) within 7 days

Sung Woon Moon; Moo Sang Kim; Eung Suk Kim; Seung-Young Yu; Hyung-Woo Kwak

2011-01-01

396

Histopathology of prostate tissue after vascular-targeted photodynamic therapy for localized prostate cancer.  

PubMed

Low-risk prostate adenocarcinoma is classically managed either with active surveillance or radical therapy (such as external radiotherapy or radical prostatectomy), but both have significant side effects. Vascular-targeted photodynamic therapy (VTP) is a focal therapy proposed as an alternative approach for localized, low-volume, and low-Gleason score (?6) carcinomas. We report histological modifications observed in prostate biopsies of 56 patients, performed 6 months after VTP using the photosensitizer TOOKAD® Soluble (WST11) and low-energy laser administered in the tumor area transperineally by optic fibers. In 53 patients, we observed sharply demarcated hyaline fibrotic scars, with or without rare atrophic glands, sometimes reduced to corpora amylacea surrounded by giant multinuclear macrophages. Mild chronic inflammation, hemosiderin, and coagulative necrosis were also observed. When residual cancer was present in a treated lobe (17 patients), it was always located outside the scar, most often close to the prostate capsule, and it showed no therapy-related modification. Histopathological interpretation of post-WST11 VTP prostate biopsies was straightforward, in contrast with that of prostate biopsies after radio or hormonal therapy, which introduces lesions difficult to interpret. VTP resulted in complete ablation of cancer in the targeted area. PMID:23948957

Eymerit-Morin, Caroline; Zidane, Merzouka; Lebdai, Souhil; Triau, Stéphane; Azzouzi, Abdel Rahmene; Rousselet, Marie-Christine

2013-08-16

397

LASER BIOLOGY AND MEDICINE: A laser-spectroscopy system for fluorescent diagnostics and photodynamic therapy of diseases of eye retina and choroid  

NASA Astrophysics Data System (ADS)

A laser-spectroscopy system for the fluorescent diagnostics and photodynamic therapy of pathologic eye-fundus changes combined with the use of the Photosens compound is developed. The system is tested on experimental animals (mice and rabbits).

Meerovich, G. A.; Shevchik, S. A.; Loshchenov, M. V.; Budzinskaya, M. V.; Ermakova, N. A.; Kharnas, S. S.

2002-11-01

398

Adjuvant therapy for intrahepatic cholangiocarcinoma: the debate continues.  

PubMed

Presentation of the Case A 37-year-old woman presented at 35 weeks of gestation with her third child with failure to adequately gain weight and was noted by her obstetrician to have delay in the growth of her baby. Ultrasound of the abdomen incidentally revealed the presence of a liver lesion. After additional evaluation, she ultimately delivered her daughter at 36 weeks uneventfully. She subsequently underwent additional evaluation. Liver magnetic resonance imaging (MRI) revealed a 5-cm solitary solid mass in segment 4A of the liver, concerning for malignancy. Serum ?-fetoprotein, carcinoembryonic antigen, cancer antigen (CA)19-9, CA15-3, and CA125 were all normal. Liver biopsy was positive for adenocarcinoma. The tumor cells demonstrated a phenotype suggesting a possible breast primary, although the immunohistochemistry did not support that diagnosis and the tumor was negative for mammaglobin, gross cystic disease fluid protein (GCDFP)-15, estrogen receptor (ER), and progesterone receptor (PR) (Table 1). The tumor was also CDX2 and cardiotrophin-1 negative, but cytokeratin (CK) 19 positive. Her endoscopic retrograde cholangiopancreatography, upper endoscopy, colonoscopy, breast mammogram, and breast MRI were completely normal. A positron emission tomography-computed tomography scan showed a fluorodeoxyglucose-avid 5.8-cm × 6.0-cm hypoattenuating lesion with peripheral enhancement involving segment 4 and segment 8 at the dome. In addition, central necrosis within the lesion was noted. The left main portal vein was mildly attenuated by the mass. She eventually underwent a left hepatectomy en bloc with caudate resection, portal lymphadenectomy, cholecystectomy, and omental pedicle flap. On exploration of the abdomen, no additional disease was noted. The final pathology revealed a 9.4-cm moderately to poorly differentiated adenocarcinoma of the intrahepatic bile ducts. Venous invasion was present. Perineural invasion was absent. The margins were negative. Thirteen lymph nodes were obtained, all of which were negative, consistent with a stage T2, N0, MX intrahepatic cholangiocarcinoma. The tumor was positive for CK7, CK19, and CA19-9 and negative for CK20, CDX2, CA125, ER, PR, GCDFP-15, synaptophysin, and chromogranin (Table 1). The uninvolved liver was unremarkable and a trichrome stain showed no fibrosis. Following an uneventful postoperative recovery, she was referred for consideration of adjuvant therapy. PMID:23220842

Zhu, Andrew X; Knox, Jennifer J

2012-12-07

399

Systemic meningococcal infection: Which children may benefit from adjuvant haemostatic therapy? Results from an observational study  

Microsoft Academic Search

The potential benefits of haemostatic therapy (heparin, antithrombin (AT) concentrate, fresh frozen plasma (FFP)) in severe systemic meningococcal infections (SMI) are controversial. A reduction of the still high case fatality rate would be an important indicator for potential benefits of adjuvant haemostatic therapy in children with SMI. Observational data from nationwide, active surveillance for SMI in children under 16 years

W. Nürnberger; R. v. Kries; O. Böhm; U. Göbel

1999-01-01

400

Selection of men at high risk for disease recurrence for experimental adjuvant therapy following radical prostatectomy  

Microsoft Academic Search

ObjectivesFollowing surgery, men with recurrent prostate cancer have an isolated elevation in serum prostate-specific antigen (PSA) well in advance of measurable metastatic disease. Rational patient selection for new forms of adjuvant therapy, for example, gene therapy, is imperative.

Alan W. Partin; James L. Mohler; Steven Piantadosi; Charles B. Brendler; Martin G. Sanda; Patrick C. Walsh; Jonathan I. Epstein; Jonathan W. Simons; Fray F. Marshall

1995-01-01

401

Effects of Adjuvant Chemohormonal Therapy on the Ovarian and Adrenal Function of Breast Cancer Patients1  

Microsoft Academic Search

Ovarian and adrenal function were studied in premenopausal breast cancer patients before and at intervals during adjuvant therapy with cyclophosphamide, methotrexate, and 5-fluorour- acil (CMF), CMF plus prednisone (CMFP), or CMFP plus ta- moxifen (CMFPT). Amenorrhea developed within 10 months of starting therapy in 13 of 15 patients given CMF, 8 of 10 receiving CMFP, and all of 13 CMFPT-treated

David P. Rose; Thomas E. Davis

402

Serous Retinal Detachment Following Combined Photodynamic Therapy and Intravitreal Bevacizumab Injection  

PubMed Central

We report a case of serous retinal detachment following combined photodynamic therapy (PDT) and intravitreal bevacizumab injection in subfoveal choroidal neovascularization (CNV). A 53-year-old woman was diagnosed with subfoveal CNV secondary to age-related macular degeneration (AMD) and treated with combined PDT and intravitreal bevacizumab injection. One day after treatment, the patient experienced a sudden decline of vision and optical coherence tomography (OCT) showed serous retinal detachment involving the macula. She was managed conservatively with an oral steroid beginning on the second day of the combined treatment and the subretinal fluid started to decrease one week following the initiation of steroids. This case suggests that combined PDT and intravitreal injection of bevacizumab can be associated with serous retinal detachment. Additional studies are needed to establish the safety and complications following this treatment regimen.

Kim, Eui Yon; Kim, Jong Wan; Kim, Jun Bum

2009-01-01

403

Nanocarriers with ultrahigh chromophore loading for fluorescence bio-imaging and photodynamic therapy.  

PubMed

We describe the design of original nanocarriers that allows for ultrahigh chromophore loading while maintaining the photo-activity of each individual molecule. They consist in shells of charged biocompatible polymers grafted on gold nanospheres. The self-organization of extended polymer chains results from repulsive charges and steric interactions that are optimized by tuning the surface curvature of nanoparticles. This type of nano-scaffolds can be used as light-activated theranostic agents for fluorescence imaging and photodynamic therapy. We demonstrate that, labeled with a fluorescent photosensitizer, it can localize therapeutic molecules before triggering the cell death of B16-F10 melanoma with an efficiency that is similar to the efficiency of the polymer conjugate alone, and with the advantage of extremely high local loading of photosensitizers (object concentration in the picomolar range). PMID:23915950

Navarro, Julien R G; Lerouge, Frédéric; Cepraga, Cristina; Micouin, Guillaume; Favier, Arnaud; Chateau, Denis; Charreyre, Marie-Thérèse; Lanoë, Pierre-Henri; Monnereau, Cyrille; Chaput, Frédéric; Marotte, Sophie; Leverrier, Yann; Marvel, Jacqueline; Kamada, Kenji; Andraud, Chantal; Baldeck, Patrice L; Parola, Stephane

2013-07-31

404

Bisanthracene Bis(dicarboxylic imide)s as Potential Photosensitizers in Photodynamic Therapy: A Theoretical Investigation.  

PubMed

The electronic structures and spectroscopic properties of four bisanthracene bis(dicarboxylic imide)s (M1-M4) have been investigated theoretically by using density functional theory (DFT) and its time-dependent extension (TDDFT) in view of their potential use as photosensitizers in photodynamic therapy (PDT). The optimized geometries, electronic absorption transitions, singlet-triplet energy gaps, spin-orbit matrix elements, ionization potentials, and electron affinities have been determined in gas phase and in solvent. Both type I and II PDT mechanisms have been considered. In addition, the variation of a series of relevant properties upon heavy atom substitution (Br and I) have been determined and discussed. Results show that only M4 is able to support the type I reaction, and one of its brominated and iodinated derivatives can produce cytotoxic singlet oxygen (type II reaction). PMID:23899186

Alberto, Marta E; Iuga, Cristina; Quartarolo, Angelo D; Russo, Nino

2013-08-14

405

Photodynamic therapy on spontaneous tumors of dogs and cats: a ten-year study  

NASA Astrophysics Data System (ADS)

Since 1981, more than fifty spontaneous tumors of dogs and cats were treated by photodynamic therapy with hematoporphyrins in the surgery department of the University of Milan. Therapeutic results proved to be successful and promising in certain forms of cancer and will be compared in the future with the effectiveness of other photosensitizer drugs like phatolocyanines derivatives. Applied hematoporphyrins phototherapy methods included: (1) injection of hematoporphyrins derivative (HpD) and irradiation with laser light at 631 nanometers, using a Rhodamine B dye laser; (2) injection of the active component of hematoporphyrin derivative (DHE) and irradiation with a Rhodamine B dye laser; and (3) injection of DHE and irradiation with laser light at 628 nanometers using a gold vapor laser. More frequently treated tumor sites were oral and nasal cavities. Other localizations were mucous membranes of the glans and stomach. Nineteen histological types were diagnosed in treated tumors.

Fonda, Diego

1992-06-01

406

Application of backward diffuse reflection spectroscopy for monitoring the state of tissues in photodynamic therapy  

SciTech Connect

The application of backward diffuse reflection (BDR) spectroscopy for in vivo monitoring the degree of haemoglobin oxygenation and concentration of photosensitisers in tissues subjected to photodynamic therapy is demonstrated. A simple experimental technique is proposed for measuring diffuse reflection spectra. The measurements are made under steady-state conditions using a fibreoptic probe with one transmitting and one receiving fibre separated by a fixed distance. Although this approach does not ensure the separation of contributions of scattering and absorption to the spectra being measured, it can be used for estimating the degree of haemoglobin oxygenation and concentration of photosensitisers in the tissues. Simple expressions for estimating the concentration of photosensitisers from the BDR spectra are presented and the accuracy of this approach is analysed. The results of application of BDR spectroscopy for monitoring various photosensitisers are considered. (special issue devoted to multiple radiation scattering in random media)

Stratonnikov, Aleksandr A; Meerovich, G A; Ryabova, A V; Savel'eva, T A; Loshchenov, V B [Natural Science Center, A.M. Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2006-12-31

407

Imaging a photodynamic therapy photosensitizer in vivo with a time-gated fluorescence tomography system  

NASA Astrophysics Data System (ADS)

We report the tomographic imaging of a photodynamic therapy (PDT) photosensitizer, 2-(1-hexyloxyethyl)-2-devinyl pyropheophorbide-a (HPPH) in vivo with time-domain fluorescence diffuse optical tomography (TD-FDOT). Simultaneous reconstruction of fluorescence yield and lifetime of HPPH was performed before and after PDT. The methodology was validated in phantom experiments, and depth-resolved in vivo imaging was achieved through simultaneous three-dimensional (3-D) mappings of fluorescence yield and lifetime contrasts. The tomographic images of a human head-and-neck xenograft in a mouse confirmed the preferential uptake and retention of HPPH by the tumor 24-h post-injection. HPPH-mediated PDT induced significant changes in fluorescence yield and lifetime. This pilot study demonstrates that TD-FDOT may be a good imaging modality for assessing photosensitizer distributions in deep tissue during PDT monitoring.

Mo, Weirong; Rohrbach, Daniel; Sunar, Ulas

2012-07-01

408

Photodynamic therapy for early gastric cancer: its application for wider lesions  

NASA Astrophysics Data System (ADS)

For the application of photodynamic therapy (PDT) for wider lesions of early gastric cancer we employed a new model of an excimer dye laser (EDL), because it is necessary to increase the average output for the irradiation of enough energy to the wider lesion within a limited time, in addition to protecting the single quartz fiber from destruction. The characteristics of the new laser are as follows: wavelength, 630 nm; pulse energy, 4 mJ; peak power, 400 kW; pulse width, 10 nsec; frequency of repetition, 80 Hz; average output, 320 mW. The PDT can be applicable for wider lesions of early gastric cancer by employing the new model of EDL, that can produce the average output of 320 mW with repetition of 4 mJ in 80 times per second.

Mimura, Seishiro; Narahara, Hiroyuki; Otani, Toru; Okuda, Shigeru

1995-03-01

409

Photodynamic therapy for early gastric cancer: its application for wider lesions  

NASA Astrophysics Data System (ADS)

For the application of photodynamic therapy (PDT) for wider lesions of early gastric cancer we employed a new model of an excimer dye laser (EDL), because it is necessary to increase the average output for the irradiation of enough energy to the wider lesion within a limited time, in addition to protecting the single quartz fiber from destruction. The characteristics of the new laser are as follows: wavelength, 630 nm; pulse energy, 4 mJ; peak power, 400 kW; pulse width, 10 nsec; frequency of repetition, 80 Hz; average output, 320 mW. The PDT can be applicable for wider lesions of early gastric cancer by employing the new model of EDL, that can produce the average output of 320 mW with repetition of 4 mJ in 80 times per second.

Mimura, Seishiro; Narahara, Hiroyuki; Otani, Toru; Okuda, Shigeru

1994-10-01

410

Controlling silica coating thickness on TiO2 nanoparticles for effective photodynamic therapy.  

PubMed

Photosensitive nanoparticles are useful in developing phototherapeutic agents for targeted cancer therapy. In this paper, core-shell structured titanium dioxide-silica (TiO2-SiO2) nanoparticles, with varying shell thickness, were synthesized. The influence of the silica shell thickness on the photoreactivity, cytotoxicity and photo-killing ability of the TiO2 nanoparticles was investigated. Silica coating reduced the photocatalytic reactivity but improved the cytocompatibility of the TiO2 nanoparticles. This effect was amplified with increasing silica shell thickness. When the silica thickness was about 5.5 nm, the coated TiO2 not only retained a high level photodynamic reactivity, comparable to the non-coated TiO2 nanoparticles, but also demonstrated an improved cell compatibility and effective photo-killing ability upon the mouse fibroblast cells (L929). PMID:23502045

Feng, Xiaohui; Zhang, Shaokun; Lou, Xia

2013-02-21

411

Topical 4-thiothymidine is a viable photosensitiser for the photodynamic therapy of skin malignancies.  

PubMed

The nucleoside analogue 4-thiothymidine has shown great potential in vitro as a photosensitiser for the photodynamic therapy of numerous cancer cell lines. However, the limited penetrating power of UV-A radiation, to which it responds, raises doubts as to its practical usefulness in clinical applications. We addressed this issue by studying the penetration extent of topical thiothymidine and the antiproliferative effect of its combination with UV-A radiation on ex vivo basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) skin cancer biopsies, and normal skin. Our results show that both the intralesional concentration of the drug and the intensity of UV-A radiation are sufficient to activate the molecule and cause extensive death by apoptosis of the malignant cells. Normal skin biopsies were not significantly affected by the treatment. PMID:22007698

Gemenetzidis, Emilios; Shavorskaya, Oksana; Xu, Yao-Zhong; Trigiante, Giuseppe

2011-11-10

412

Photodynamic therapy using 5-aminolevulinic acid-induced photosensitization: current clinical status  

NASA Astrophysics Data System (ADS)

Photodynamic therapy using 5-aminolevulinic acid-induced photosensitization (ALA PDT) via endogenous protoporphyrin IX (PpIX) synthesis has been reported as efficacious, using topical formulations, in the treatment of a variety of dermatologic diseases including superficial basal cell carcinoma, Bowen's disease, and actinic (solar) keratoses. Application of ALA PDT to the detection and treatment of both malignant and non-malignant diseases of internal organs has recently been reported. Local internal application of ALA has been used for the detection, via PpIX fluorescence, of pathological conditions of the human urinary bladder and for selective endometrial ablation in animal model systems. Systemic, oral administration of ALA has been used for ALA PDT of superficial head and neck cancer and of colorectal cancer. This paper reviews the current clinical status of ALA PDT.

Marcus, Stuart L.; Golub, Allyn L.; Shulman, D. Geoffrey

1995-03-01

413

Photodynamic therapy using 5-aminolevulinic acid-induced photosensitization: current clinical status  

NASA Astrophysics Data System (ADS)

Photodynamic therapy using 5-aminolevulinic acid-induced photosensitization (ALA PDT) via endogenous protoporphyrin IX (PpIX) synthesis has been reported as efficacious, using topical formulations, in the treatment of a variety of dermatologic diseases including superficial basal cell carcinoma, Bowen's disease, and actinic (solar) keratoses. Application of ALA PDT to the detection and treatment of both malignant and non-malignant diseases of internal organs has recently been reported. Local internal application of ALA has been used for the detection, via PpIX fluorescence, of pathological conditions of the human urinary bladder and for selective endometrial ablation in animal model systems. Systemic, oral administration of ALA has been used for ALA PDT of superficial head and neck cancer and of colorectal cancer. This paper reviews the current clinical status of ALA PDT.

Marcus, Stuart L.; Golub, Allyn L.; Shulman, D. Geoffrey

1994-10-01

414

In vitro investigation of efficient photodynamic therapy using a nonviral vector; hemagglutinating virus of Japan envelope  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is a photochemical modality approved for cancer treatment. PDT has demonstrated efficacy in early stage lung cancer and esophageal cancer. The accumulation of photosensitizers in cancer cells is necessary to enhance the therapeutic benefits of PDT; however, photosensitizers have low uptake efficiency. To overcome this limitation, a drug delivery system, such as the hemagglutinating virus of Japan envelope (HVJ-E) vector, is required. In this study, the combination of PDT and HVJ-E was investigated for enhancing the efficacy of PDT. The photosensitizers that were evaluated included 5-aminolaevulinic acid (5-ALA), protoporphyrin IX (PPIX), and HVJ-PPIX. The uptake of the photosensitizers as increased twenty-fold with the addition of HVJ-E. The cytotoxicity of conventional 5-ALA was enhanced by the addition of HVJ-E vector. In conclusion, HVJ-E vector improved the uptake of photosensitizers and the PDT effect.

Sakai, Makoto; Fujimoto, Naohiro; Ishii, Katsunori; Nakamura, Hiroyuki; Kaneda, Yasufumi; Awazu, Kunio

2012-07-01

415

Photodynamic Therapy Rescue for Subretinal Fluid Exacerbation After Focal Laser Treatment in Idiopathic Central Serous Chorioretinopathy  

PubMed Central

Purpose To report a case of subretinal leakage after focal laser treatment for idiopathic central serous chorioretinopathy (ICSC). This rare complication was successfully treated with photodynamic therapy (PDT). Methods Interventional case report. Results A 36-year-old male presented with ICSC in his right eye. After a period of observation without resolution, he was treated with focal laser. That treatment resulted in a massive exacerbation of his subretinal fluid. PDT was successfully used to treat the severe exacerbation with rapid resolution of the subretinal fluid, improvement in visual acuity, decreased leakage on fluorescein angiography, and reduction of subretinal fluid on ophthalmoscopic exam and by optical coherence tomography. Conclusions Ophthalmologists should consider the use of PDT in cases where focal laser causes an exacerbation of subretinal fluid in ICSC.

Leng, Theodore; Sanislo, Steven R; Jack, Robert L

2011-01-01

416

Light dosage in whole bladder wall photodynamic therapy at 532 and 630 nm  

NASA Astrophysics Data System (ADS)

The optical absorption, scattering and anisotropy coefficient of piglet and diseased human bladder tissue were determined in vitro in the wavelength range of 500 - 650 nm. Monte Carlo simulations for whole bladder wall (WBW) photodynamic therapy (PDT) have been performed using the optical parameters determined in vitro. The calculated light dose rate values are in agreement with those measured in clinical WBW-PDT, previously performed at 630 nm. The light dose rate at the bladder wall can differ by a factor of 4, due to variations in optical properties of the tissue. This demonstrates the necessity of in situ light dosimetry during clinical WBW-PDT. WBW-PDT with red light (630 nm) will be technically more advantageous than with green light (532 nm), because of a higher integrating sphere effect.

van Staveren, Hugo J.; Ramaekers, Joost W.; Marijnissen, Johannes P.; Beek, Johan F.; Keijzer, Marleen; Star, Willem M.

1994-03-01

417

Monomeric pheophorbide(a)-containing poly(ethyleneglycol-b-epsilon-caprolactone) micelles for photodynamic therapy.  

PubMed

Incorporation of unaggregated monomeric molecules of pheophorbide(a) into micelles of poly(ethyleneoxide-b-epsilon-caprolactone) has been characterized by fluorescence spectroscopy, dynamic light scattering, transmission electron microscopy and asymmetric flow field flow fractionation. It was shown that the method used leads to 20 nm micelles, corresponding to approximately 200 molecules of polymer and 4 molecules of monomeric pheophorbide(a) per nano-object which was able to generate (1)O(2) in the medium. They have been used thereafter as nanocarriers for photosensitizers in photodynamic therapy against cancer cells. The encapsulation of photosensitizer has been verified and in vitro tests on human cancerous cells have revealed a ca. 2-fold enhanced photocytotoxicity and cellular uptake compared to free pheophorbide(a). PMID:19255682

Knop, Katrin; Mingotaud, Anne-Françoise; El-Akra, Naram; Violleau, Frédéric; Souchard, Jean-Pierre

2009-01-21

418

Photodynamic therapy of the atherosclerotic abdominal aorta by laparoscopical approach using a pheophorbide derivative  

NASA Astrophysics Data System (ADS)

A new photosensitizer, PH-1126, was administered intravenously into the ear vein of cholesterol-fed atherosclerotic rabbits at a dose of 1 mg/kg of body weight. At 24 hours after PH-1126 administration, the atherosclerotic lesions of the abdominal aorta were irradiated by krypton ion laser at 647 nm of wavelength with 100 J/cm2. The abdominal aorta irradiated by laser beam was excised for histological analysis using the scanning electron microscopy and transmission electron microscopy. In the atherosclerotic plaque irradiated by krypton ion laser, migratory cells were observed and some of these cells were migrated into the lumen of the vessel. These findings suggested that these migratory cells from atherosclerotic plaque were foam cells destroyed by photodynamic therapy.

Saito, Takashi; Hayashi, Junichi; Sato, Hideaki; Kawabe, Hirofumi; Aizawa, Katsuo

1994-10-01

419

Photodynamic therapy of the atherosclerotic abdominal aorta by laparoscopical approach using a pheophorbide derivative  

NASA Astrophysics Data System (ADS)

A new photosensitizer, PH-1126, was administered intravenously into the ear vein of cholesterol-fed atherosclerotic rabbits at a dose of 1 mg/kg of body weight. At 24 hours after PH-1126 administration, the atherosclerotic lesions of the abdominal aorta were irradiated by krypton ion laser at 647 nm of wavelength with 100 J/cm2. The abdominal aorta irradiated by laser beam was excised for histological analysis using the scanning electron microscopy and transmission electron microscopy. In the atherosclerotic plaque irradiated by krypton ion laser, migratory cells were observed and some of these cells were migrated into the lumen of the vessel. These findings suggested that these migratory cells from atherosclerotic plaque were foam cells destroyed by photodynamic therapy.

Saito, Takashi; Hayashi, Junichi; Sato, Hideaki; Kawabe, Hirofumi; Aizawa, Katsuo

1995-03-01

420

Synthesis and biological evaluation of new chlorin derivatives as potential photosensitizers for photodynamic therapy.  

PubMed

Three new water-soluble chlorin derivatives 3, 5 and 8 for potential use as photosensitizers in photodynamic therapy (PDT) for cancer were synthesized from photoprotoporphyrin IX dimethyl ester (1). The in vivo biodistribution and clearance of chlorin derivatives 3, 5 and 8 were investigated in tumor-bearing mice. Iminodiacetic acid derivative 8 showed the greatest tumor-selectiv