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1

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

2

Examples of adjuvant treatment enhancing the antitumor effect of photodynamic therapy  

NASA Astrophysics Data System (ADS)

Strategies for improving the clinical efficacy of photodynamic therapy (PDT) in treatment of solid cancers include applications of different types of adjuvant treatments in addition to this modality that may result in superior therapeutic outcome. Examples of such an approach investigated using mouse tumor models are presented in this report. It is shown that the cures of PDT treated subcutaneous tumors can be substantially improved by adjuvant therapy with: metoclopramide (enhancement of cancer cell apoptosis), combretastatin A-4 (selective destruction of tumor neovasculature), Roussin's Black Salt (light activated tumor localized release of nitric oxide), or dendritic cell-based adoptive immunotherapy (immune rejection of treated tumor).

Korbelik, Mladen; Cecic, Ivana; Sun, Jinghai; Chaplin, David J.

1999-07-01

3

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

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

Photodynamic therapy.  

PubMed

Photodynamic therapy (PDT) relies on the interaction between a photosensitizer, the appropriate wavelength, and oxygen to cause cell death. First introduced about 100 years ago, PDT has continued to evolve in dermatology into a safe and effective treatment option for several dermatologic conditions. PDT is also used by pulmonologists, urologists, and ophthalmologists. This article focuses on the history of PDT, mechanism of action, photosensitizers and light sources used, therapeutic applications and expected dermatologic outcomes, as well as management of adverse events. PMID:24891062

Rkein, Ali M; Ozog, David M

2014-07-01

6

Indocyanine green (ICG) as a new adjuvant for the antimicrobial photo-dynamic therapy (aPDT) in dentistry  

NASA Astrophysics Data System (ADS)

Clinical surveys show a continuous increase of antimicrobial resistance related to the frequency of the administrated medication. The antimicrobial photodynamic therapy (aPDT) is an effective adjuvant to reduce the need of antibiotics in dentistry, especially in periodontics. The antimicrobial effect of lightactivated photosensitizers in periodontics is demonstrated in clinical studies and case reports. Indocyanine green (ICG) as a new adjuvant shows the high potential of antiphlogistic and antimicrobial effects in combination with laser-light activation. In trying to answer the question of just how far the influence of temperature is acting on bacteria, this study was carried out. The influences of ICG at different concentrations (0.01 up to 1 mg/ml) in combination with a culture medium (brain-heart-infusion) and a bacteria culture (Streptococcus salivarius) at different optical densities (OD600 0.5 and 0.1) were investigated under laser-light activation. Laser activation was carried out with diode laser at 810 nm and two different power settings (100 mW/300 mW). The pulse repetition rate was 2 kHz. Taking account of the fiber diameter, distance and spot size on the sample surface, the applicated intensities were 6.2 and 18.7 W/cm2. Total irradiation time was 20 s for all meaurements. Transmitted laser power and temperature increase in the culture medium as well as in the bacteria culture were determined. Additionally the influence of ICG regarding bacterial growth and bactericidal effect was investigated in the bacteria culture without laser irradiation. Without laser, no bactericidal effect of ICG was observed. Only a bacteriostatic effect could be proved. In dependence of the ICG concentration and the applied intensities a temperature increase of ?T up to 80°C was measured.

Meister, Joerg; Hopp, Michael; Schäfers, Johannes; Verbeek, Jonas; Kraus, Dominik; Frentzen, Matthias

2014-02-01

7

[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

8

Photodynamic therapy with fullerenes†  

PubMed Central

Fullerenes are a class of closed-cage nanomaterials made exclusively from carbon atoms. A great deal of attention has been focused on developing medical uses of these unique molecules especially when they are derivatized with functional groups to make them soluble and therefore able to interact with biological systems. Due to their extended ?-conjugation they absorb visible light, have a high triplet yield and can generate reactive oxygen species upon illumination, suggesting a possible role of fullerenes in photodynamic therapy. Depending on the functional groups introduced into the molecule, fullerenes can effectively photoinactivate either or both pathogenic microbial cells and malignant cancer cells. The mechanism appears to involve superoxide anion as well as singlet oxygen, and under the right conditions fullerenes may have advantages over clinically applied photosensitizers for mediating photodynamic therapy of certain diseases.

Mroz, Pawel; Tegos, George P.; Gali, Hariprasad; Wharton, Tim; Sarna, Tadeusz; Hamblin, Michael R.

2010-01-01

9

Intracranial Photodynamic Therapy  

NASA Astrophysics Data System (ADS)

This chapter presents the use of photodynamic therapy (PDT) for clinical applications in the brain, particularly treatment of patients with solid brain tumors such as malignant gliomas. The principles and background of PDT are first described, followed by a summary of brain tumors and presentation of a heuristic model that serves to illustrate how PDT may be utilized. Subsequent sections will summarize what has been achieved to date in intracranial applications of PDT, and then the particular technical challenges that brain tumors pose for effective delivery of PDT treatment and some of the photophysical, photochemical, and photobiological strategies that have been explored to overcome these. The final section looks ahead to potential future needs and developments, both fundamental and practical.

Wilson, Brian C.; Madsen, Steen J.

10

[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

11

Medical complex for photodynamic therapy  

NASA Astrophysics Data System (ADS)

Experimental results of initial testing dye-laser 'MLK-02' pumped by a copper vapor laser 'Kulon-10' are presented. Output parameters obtained are the following: average power - 1 and 1.5 W, efficiency - 17.6 and 18.7% at the wavelengths of 670 and 725 nm, respectively. The laser apparatus is supposed to be used for methods of photodynamic therapy.

Soldatov, Anatoly N.; Domanov, Michail S.; Lyabin, Nikolay A.; Chursin, Alexandr D.; Mirza, Sergey Y.; Sukhanov, Viktor B.; Polunin, Yu. P.; Ivanov, Aleksandr I.; Kirilov, Anatoly E.; Rubanov, Sergey N.

2002-03-01

12

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

13

Veterinary photodynamic therapy: a review.  

PubMed

Whereas in human medicine photodynamic therapy represents a well-known and recognized treatment option for diverse indications, it is still little known and unfortunately not yet established treatment option for pets. Various photosensitizers and light sources have been used and clinical results have been published. The main indication is a frequently occurring skin tumor in cats: in situ carcinoma/squamous cell carcinoma, mainly found in not or only slightly pigmented areas of the head. For early stages of this tumor, promising results have been published, partly using new, selective drugs to decrease light sensitivity after systemic administration and to increase response rates. Other possible indications are urinary tract neoplasia of dogs and equine sarcoids, the latter representing very common tumors in horses where no effective treatment is known so far. This review article summarizes the role of photodynamic therapy in veterinary medicine. PMID:24284083

Buchholz, Julia; Walt, Heinrich

2013-12-01

14

Histomorphometric and Microbiological Assessment of Photodynamic Therapy as an Adjuvant Treatment for Periodontitis: A Short-Term Evaluation of Inflammatory Periodontal Conditions and Bacterial Reduction in a Rat Model  

PubMed Central

Abstract Objective: The aim of this study was to investigate the short-term effects of photodynamic therapy (PDT) in periodontal tissue when it is used as an adjuvant treatment for periodontitis. Background data: PDT has been used as an adjuvant in the combat of local infections, such as periodontitis, and combines a photosensitizer (PS) with a light source to induce reactive oxygen species (ROS) and kill microbial cells. Methods: Fifty healthy male rats were used in this study. Periodontitis was induced by placing a cotton ligature around the upper left second molar in a subgingival position. Posterior maxillas were removed and histologically prepared with hematoxylin & eosin (H&E) staining techniques. PDT was performed with a diode laser (?=660?nm) with an output power of 100?mW. Methylene blue aqueous solution (100??M) was used as the PS while control group used phosphate buffered saline (PBS). Collagen organization, inflammatory infiltrate, and bone loss were evaluated. Bacterial samples were collected before and immediately after treatment to determine bacterial reduction. Results: The experimental group that was treated with PDT presented better periodontal healing, as measured by collagen organization, inflammatory infiltrate, and bone loss. Significant bacterial reduction was achieved following treatment with or without PDT compared to control, with a higher microbial reduction observed in the PDT group. Conclusions: PDT used as an adjuvant treatment showed effective short-term control of periodontitis infection.

Yamada, Aecio M.; Suzuki, Luis C.; Franca, Cristiane M.; Cai, Silvana; Mayer, Marcia P.A.; Ribeiro, Adriana C.; Ribeiro, Martha S.

2011-01-01

15

Adjuvant therapy for colorectal cancer  

Microsoft Academic Search

In recent years, adjuvant therapy for colorectal cancer has advanced considerably. This article reviews these advances and provides an update of the most recent and ongoing trials. In 1990, adjuvant therapy became the standard of care for patients with Stage III colon cancer (Dukes C) in the United States. Recent clinical trial data indicate that adjuvant treatment may also be

Sergio Casillas; Robert J. Pelley; Jeffrey W. Milsom

1997-01-01

16

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

17

Photodynamic Therapy and Central Serous Chorioretinopathy  

PubMed Central

Central serous chorioretinopathy is a common acquired maculopathy. Multiple studies showed that photodynamic therapy is useful treatment for acute and chronic central serous chorioretinopathy. The exact mechanism of photodynamic therapy in treating central serous chorioretinopathy is not clear, but it is thought to be caused by short-term choriocapillaris hypoperfusion and long-term choroidal vascular remodeling, leading to a reduction in choroidal congestion, vascular hyperpermeability and extravascular leakage. Furthermore, photodynamic therapy seems to be an effective means of improving or stabilizing visual acuity in patients with central serous chorioretinopathy.

Siaudvytyte, Lina; Diliene, Vaida; Miniauskiene, Goda; Balciuniene, Vilma Jurate

2012-01-01

18

Antimicrobial photodynamic therapy: An overview  

PubMed Central

Inflammatory periodontal disease caused by dental plaque is characterized by the clinical signs of inflammation and loss of periodontal tissue support. The mechanical removal of this biofilm and adjunctive use of antibacterial disinfectants and antibiotics have been the conventional methods of periodontal therapy. But the removal of plaque and the reduction in the number of infectious organisms can be impaired in sites with difficult access. The possibility of development of resistance to antibiotics by the target organism has led to the development of a new antimicrobial concept with fewer complications. Photodynamic therapy (PDT) involves the use of low power lasers with appropriate wavelength to kill micro organisms treated with a photosensitizer drug. PDT could be a useful adjunct to mechanical as well as antibiotics in eliminating periopathogenic bacteria.

Rajesh, S.; Koshi, Elizabeth; Philip, Koshi; Mohan, Aparna

2011-01-01

19

Photodynamic therapy of acne vulgaris.  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) with topical 5-aminolevulinic acid (ALA) was tested for the treatment of acne vulgaris. Patients with acne were treated with ALA plus red light. Ten percent water solution of ALA was applied with 1,5-2 h occlusion and then 18-45 J/cm2 630 nm light was given. Bacterial endogenous porphyrins fluorescence also was used for acne therapy. Treatment control and diagnostics was realized by fluorescence spectra and fluorescence image. Light sources and diagnostic systems were used: semiconductor laser (?=630 nm, Pmax=1W), (LPhT-630-01-BIOSPEC); LED system for PDT and diagnostics with fluorescent imager (?=635 nm, P=2W, p=50 mW/cm2), (UFPh-630-01-BIOSPEC); high sensitivity CCD video camera with narrow-band wavelength filter (central wavelength 630 nm); laser electronic spectrum analyzer for fluorescent diagnostics and photodynamic therapy monitoring (LESA-01-BIOSPEC). Protoporphyrin IX (PP IX) and endogenous porphyrins concentrations were measured by fluorescence at wavelength, correspondingly, 700 nm and 650 nm. It was shown that topical ALA is converted into PP IX in hair follicles, sebaceous glands and acne scars. The amount of resulting PP IX is sufficient for effective PDT. There was good clinical response and considerable clearance of acne lesion. ALA-PDT also had good cosmetic effect in treatment acne scars. PDT with ALA and red light assist in opening corked pores, destroying Propionibacterium acnes and decreasing sebum secretion. PDT treatment associated with several adverse effects: oedema and/or erytema for 3-5 days after PDT, epidermal exfoliation from 5th to 10th day and slight pigmentation during 1 month after PDT. ALA-PDT is effective for acne and can be used despite several side effects.

Ershova, Ekaterina Y.; Karimova, Lubov N.; Kharnas, Sergey S.; Kuzmin, Sergey G.; Loschenov, Victor B.

2003-06-01

20

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

21

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

22

BODIPY Dyes In Photodynamic Therapy  

PubMed Central

BODIPY dyes tends to be highly fluorescent, but their emissions can be attenuated by adding substituents with appropriate oxidation potentials. Substituents like these have electrons to feed into photoexcited BODIPYs, quenching their fluorescence, thereby generating relatively long-lived triplet states. Singlet oxygen is formed when these triplet states interact with 3O2. In tissues, this causes cell damage in regions that are illuminated, and this is the basis of photodynamic therapy (PDT). The PDT agents that are currently approved for clinical use do not feature BODIPYs, but there are many reasons to believe that this situation will change. This review summarizes the attributes of BODIPY dyes for PDT, and in some related areas.

Kamkaew, Anyanee; Lim, Siang Hui; Lee, Hong Boon; Kiew, Lik Voon; Chung, Lip Yong

2012-01-01

23

Adjuvant therapy for colon cancer  

Microsoft Academic Search

Colon cancer is a leading cause of cancer and cancer deaths in Western countries. Although 5-fluorouracil is still the basis\\u000a of adjuvant therapy, advances in drug development have led to increased efficacy with the addition of oxaliplatin and options\\u000a for oral therapy with capecitabine. The benefit of adjuvant therapy for stage II disease is consistently small and not statistically\\u000a signifi-cant.

Jeffrey Cilley; Mary F. Mulcahy

2006-01-01

24

Adjuvant therapy for colon cancer.  

PubMed

As there have been advances in the treatment of metastatic colorectal cancer, exciting developments have also been achieved in the adjuvant treatment of colon cancer. At the same time, more questions have been raised, and some controversies remain. The results of the MOSAIC trial demonstrated the benefit of adding oxaliplatin to 5-fluorouracil (5-FU) and leucovorin (FOLFOX) in adjuvant therapy for stage II and III disease, but the optimal duration of therapy and the management of toxicities remain to be resolved. Capecitabine is at least equivalent to the Mayo Clinic bolus 5-FU and leucovorin regimen in the adjuvant treatment of stage III colon cancer with a lower incidence profile of adverse events, allowing additional options for patients and physicians. Routine adjuvant systemic therapy in all patients with stage II colon cancer is still debatable. Although a statistically significant advantage for adjuvant treatment in stage II disease was shown for the first time from a large randomized study (QUASAR), the subsets of patients who truly benefit from therapy need to be identified. The application of pharmacogenetics and pharmacogenomics in adjuvant therapy for colorectal cancer will help to distinguish those patients with risk factors and to guide individualized therapy. PMID:15847708

Sun, Weijing; Haller, Daniel G

2005-05-01

25

Adjuvant therapy for colon cancer  

Microsoft Academic Search

As there have been advances in the treatment of metastatic colorectal cancer, exciting developments have also been achieved\\u000a in the adjuvant treatment of colon cancer. At the same time, more questions have been raised, and some controversies remain.\\u000a The results of the MOSAIC trial demonstrated the benefit of adding oxaliplatin to 5-fluorouracil (5-FU) and leucovorin (FOLFOX)\\u000a in adjuvant therapy for

Weijing Sun; Daniel G. Haller

2005-01-01

26

Adjuvant therapy for Colon Cancer  

Microsoft Academic Search

In patients with colon cancer who undergo resection for potential cure, 40% to 60% have advanced locoregional disease and\\u000a are classified as either stage II or stage III. The role of adjuvant therapy in stage III colon cancer is well defined. The\\u000a results from the MOSAIC trial (Multicenter International Study of Oxaliplatin\\/5-Fluorouracil\\/Leucovorin in the Adjuvant Treatment\\u000a of Colon Cancer) and

Olivia Aranha; Al B. Benson III

2007-01-01

27

Strategies for targeted antimicrobial photodynamic therapy  

NASA Astrophysics Data System (ADS)

The photophysics and mechanisms of cell killing by photodynamic therapy (PDT) have been extensively studied in recent years, and PDT has received regulatory approval for the treatment of a number of diseases worldwide. As the application of this treatment modality expands with regard to both anatomical sites and diseases, it is important to develop strategies for enhancing PDT outcomes. Our group has focused on developing targeting strategies to enhance PDT for both cancerous as well as anti-microbial applications. In this article, we will discuss photosensitizer modification and conjugation strategies for targeted antimicrobial photodynamic therapy.

Verma, Sarika; Sallum, Ulysses; Zheng, Xiang; Hasan, Tayyaba

2009-06-01

28

Model of photodynamic therapy of skin tumors  

NASA Astrophysics Data System (ADS)

We have constructed a physico-mathematical model of photodynamic therapy of skin tumors taking into account the photochemical reactions and the features of the radiation propagation, the heat and mass transfer, and the mass transfer of oxygen in the irradiation zone. The numerical solution has shown that depending on the light intensity and the degree of injury of exchange vessels the concentration of oxygen in a tumor can decrease to below the hypoxic limit, which limits the photodynamic effect. We have analyzed different methods of conducting this therapy, thus increasing its success — changing the radiation intensity and hyperoxygenation.

Gubarev, S. A.; Makhanek, A. A.; Shul'Man, Z. P.

2007-01-01

29

Adjuvant therapy for pancreatic cancer.  

PubMed

Survival for patients with pancreas cancer is correlated to stage. Only 20% of patients present with localized disease amenable to potentially curative resection but, despite resection, the 5-year survival rate for early stage patients remains less than 25%. Current accepted standard of care is adjuvant gemcitabine following curative resection but there have been no conclusions regarding the role or timing of adjuvant chemoradiation. Although systemic disease represents the major risk for failure following resection, there are patients who would benefit from adjuvant local therapy that remain difficult to identify at present. This year at 2014 ASCO Gastrointestinal Cancers Symposium, Cho at al. (Abstract #325) presented the results of adjuvant gemcitabine with the addition of docetaxel followed by 5-FU chemoradiation for patients with resected pancreatic cancer. Kumar et al. (Abstract #330) compared adjuvant chemoradiation to adjuvant chemotherapy. Lastly Heestand et al. (Abstract #176) used a novel way to look at different biomarkers in serum of patients in the RTOG 9407 study and evaluated the survival depending on the type of chemotherapy used. A lower serum CEA and CA 19-9 gave a better overall survival in all patients which has already been established. Low levels of matrix metalloproteinase-7 (MMP-7) predicted an overall survival benefit from adjuvant gemcitabine, but not from 5-FU. PMID:24618424

Goodman, Martin D; Saif, Muhammad Wasif

2014-03-01

30

Adjuvant therapy for pancreatic cancer  

Microsoft Academic Search

Although the morbidity and mortality of pancreatic resection for cancer has been remarkably reduced during the last 20 years, there has been little change in long-term survival. Based on experience in the treatment of locally unresectable but nonmetastatic pancreatic cancer, adjuvant therapies have been devised that do have an impact on survival. The number of pancreatic resections remains low, however.

Harold O. Douglass

1995-01-01

31

Colorectal Cancer: Adjuvant Therapy  

Microsoft Academic Search

\\u000a The stage of disease at presentation is the most important predictor of outcome for colon cancer patients. Stage I (T1-2N0M0)\\u000a disease carries an excellent prognosis of up to 95% 5-year survival rate after resection, and surgical treatment alone is\\u000a considered sufficient; adjuvant treatment is not indicated.1 Patients with stage II disease (T3-4N0M0) also have excellent 5-year survival, averaging 70–80%, but

Kelli Bullard Dunn; Judith L. Trudel

32

Adjuvant and Neoadjuvant Therapy for Breast Cancer  

Cancer.gov

A fact sheet that explains different types of adjuvant therapy (treatment given after primary therapy to increase the chance of long-term survival) and neoadjuvant therapy (treatment given before primary therapy). Discusses side effects, risks, and benefits of adjuvant and neoadjuvant therapy for breast cancer.

33

Adjuvant therapy for endometrial cancer  

PubMed Central

Endometrial cancer is a common gynecologic malignancy typically diagnosed at early stage and cured with surgery alone. Adjuvant therapy is tailored according to the risk of recurrence, estimated based on the International Federation of Gynecology and Obstetrics (FIGO) stage and other histological factors. The objective of this manuscript is to review the evidence guiding adjuvant therapy for early stage and locally advanced uterine cancer. For patients with early stage disease, minimizing toxicity, while preserving outstanding cure rates remains the major goal. For patients with locally advanced endometrial cancer optimal combined regimens are being defined. Risk stratification based on molecular traits is under development and may aid refine the current risk prediction model and permit personalized approaches for women with endometrial cancer.

DeLeon, Maria C.; Ammakkanavar, Natraj R.

2014-01-01

34

Adjuvant therapy of colon cancer  

Microsoft Academic Search

The primary curative therapy of colorectal cancer is surgical resection. However, within the last 15 years, prospectively randomized appropriately powered clinical trials have convincingly demonstrated that adjunctive postoperative adjuvant chemotherapy is of benefit to all patients with node-positive disease (stage III) and arguably to high-risk node-negative (stage II) cases. In the United States, the clinical trials encompassing greater than 5,000

John S Macdonald; Alan B Astrow

2001-01-01

35

Photodynamic therapy in dermatology: a review  

Microsoft Academic Search

Photodynamic therapy (PDT) is used for the prevention and treatment of non-melanoma skin cancer. Until recently, clinically\\u000a approved indications have been restricted to actinic keratoses, nodular and superficial basal cell carcinoma, and, since 2006,\\u000a Bowen disease. However, the range of indications has been expanding continuously. PDT is also used for the treatment of non-malignant\\u000a conditions such as acne vulgaris and

Sonal Choudhary; Keyvan Nouri; Mohamed L. Elsaie

2009-01-01

36

Photodynamic Therapy with Verteporfin for Corneal Neovascularization  

PubMed Central

Purpose: To investigate the efficacy of photodynamic therapy (PDT) with verteporfin for the treatment of patients with corneal neovascularization. Materials and Methods: Retrospective interventional case series of 33 eyes of 32 patients with stable corneal neovascularization who were refractory to conventional treatment and were treated with single photodynamic therapy with verteporfin (6 mg/m2) at King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia between January 1, 2007 and December 30, 2009. The mean age was 40.7 ± 19 years (range 16-76 years). The mean follow-up for all patients was 13.1 ± 5.5 months (range 6-24 months). The average amount of corneal neovascularization was 2.7 ± 1.9 (1-10). Corneal neovascularization was deep in 19 (57.6%) eyes and superficial in 14 (42.4%) eyes. Preoperative and postoperative visual acuity and intraocular pressure, and clinical outcome of the treatment were assessed. Statistical analysis was performed to investigate the association to potential risk factors, to assess the change in data and determine the risks for failure. A P-value less than 0.05 was statistically significant. Results: At the last follow-up visit, 22 (66.7%) eyes showed a decrease in corneal neovascularization and evidence of vascular thrombosis. Complete vascular occlusion was achieved in 14 (42.4%) eyes, partial occlusion was achieved in 8 (24.2%) eyes, and the vessels were patent in 11 (33.3%) eyes. The corneal neovascularization score and depth of the vessels were found to be significant risk factors for failure (P = 0.0001 and 0.046, respectively). However, the diagnoses or causes of corneal neovascularisation were not statistically significant. No significant systemic or ocular complications associated with photodynamic therapy were observed. Conclusion: Photodynamic therapy with verteporfin was effective for the treatment of corneal neovascularization in the majority of the cases in this study.

Al-Torbak, Abdullah A.

2012-01-01

37

Photodynamic diagnosis and therapy in gynecology.  

PubMed

Photodynamic diagnosis (PDD) and therapy (PDT) are modern methods that are evaluated in different fields in gynecology. PDD is currently under investigation in gynecologic conditions such as cervical intraepithelial neoplasia (CIN), vulvar intraepithelial neoplasia (VIN), endometriosis, and ovarian cancer. PDT has been successfully evaluated in HPV-related genital dysplasia such as CIN and VIN, in genital warts, in local recurrent breast cancer, and for endometrial ablation. The aim of this review is to give an overview about current applications. PMID:19105537

Soergel, Philipp; Löning, Martin; Staboulidou, Ismini; Schippert, Cordula; Hillemanns, Peter

2008-01-01

38

Photodynamic Therapy for Juxtapapillary Retinal Capillary Hemangioma  

PubMed Central

Various treatment modalities have been described for retinal capillary hemangioma. Our purpose is to present a case of juxtapapillary retinal capillary hemangioma treated with photodynamic therapy. A 69-year-old woman with no previous ocular history presented with blurred vision and photopsias in the right eye three months ago. At presentation, her best corrected visual acuity was 6/9 in the right eye and 6/6 in the left eye. The anterior segment was totally normal and IOP was normal in both eyes as well. Dilated fundoscopy revealed a yellowish, well-circumscribed, elevated area with blood vessels, on the inferior margin of the right optic disc, as optic disc edema. Fluorescein angiography and angiogram with indocyanine green confirmed the diagnosis of juxtapapillary retinal capillary hemangioma. The patient was treated with photodynamic therapy with verteporfin and three months later her visual acuity was 6/7.5 in the right eye, while the lesion was slightly smaller. These findings remained stable at the one-year follow-up. In conclusion, photodynamic therapy offers promising anatomical and functional results for juxtapapillary retinal capillary hemangioma, providing visual acuity improvement or even stabilization and restriction of enlargement of the lesion.

Mitropoulos, Panagiotis G.; Chatziralli, Irini P.; Peponis, Vasileios G.; Tsiotra, Vasileia A.; Parikakis, Efstratios A.

2014-01-01

39

Photodynamic therapy with ultrafast lasers  

NASA Astrophysics Data System (ADS)

The photodynamic properties of several photosensitive compounds have been evaluated in vivo using simultaneous two-photon excitation (TPE) and multi-photon excitation (MPE). TPE and MPE are effected using a mode-locked laser, such as the mode-locked titanium:sapphire or Nd:YLF laser, the near infrared output of which allows direct promotion of various non-resonant transitions. Such lasers are exceptionally well suited for non-linear activation of exogenous or endogenous PDT agents in biological systems due to their extremely short pulse width, modest pulse energy, and high repetition rate; these features combine to effect efficient PDT activation with minimal potential for non- specific biological damage, improved spatial localization of activation, and enhanced depth of penetration. Results in several murine models are presented.

Wachter, Eric A.; Petersen, Mark G.; Dees, H. C.

1999-06-01

40

[The wider application of photodynamic therapy in dermatology].  

PubMed

Photodynamic treatment is increasingly employed in the detection and treatment of malignant and non-malignant skin disease. --Indications for photodynamic therapy so far are actinic keratosis, Bowen's disease and superficially growing basal cell carcinomas, and probably verrucae and acne vulgaris. --This technology is also currently under investigation for fluorescence diagnostics oftumour margins. --The exact position of photodynamic therapy has not yet been established because there are too less long-term comparative studies demonstrating its effectiveness. --Based on the short-term results, photodynamic therapy deserves a place within the total therapeutic arsenal of the dermatologist of today for the indications mentioned above. PMID:15719833

Thissen, M R T M; Kuijpers, D I M; Neumann, H A M

2005-01-29

41

Photodynamic therapy of cervical intraepithelial neoplasia  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is a technique that has been used for the treatment of tumors, especially in Gynecology. The photodynamic reaction is based on the production of reactive oxygen species after the activation of a photosensitizer. Advantages of the PDT in comparison to the surgical resection are: ambulatory treatment and tissue recovery highly satisfactory, through a non-invasive procedure. The cervical intraepithelial neoplasia (CIN) grades I and II presents potential indications for PDT. The aim of the proposed study is to evaluate the safety and efficacy of the PDT for the diagnostics and treatment of CIN I and II. The equipment and the photosensitizer are produced in Brazil with a representative low cost. It is possible to visualize the fluorescence of the cervix and to treat the lesions, without side effects. The proposed clinical protocol shows great potential to become a public health technique.

Inada, Natalia M.; Lombardi, Welington; Leite, Marieli F. M.; Trujillo, Jose R.; Kurachi, Cristina; Bagnato, Vanderlei S.

2014-03-01

42

Flexible textile light diffuser for photodynamic therapy  

NASA Astrophysics Data System (ADS)

In this article a new medical application is introduced using textile production techniques to deliver a defined radiation dose. The advantage for photodynamic therapy (PDT) is that a flat luminous textile structure can homogeneously illuminate unequal body surfaces. The optical properties of this two-dimensional luminous pad are characterized with a set of bench-scale tests. In vitro investigations on petri dishes with cultivated cells and first clinical tests on animal patients are promising. In addition first measurement results are presented together with an outlook to future developments.

Selm, Barbel; Camenzind, Martin

2005-03-01

43

Acceleration Of Wound Healing Ny Photodynamic Therapy  

DOEpatents

Disclosed is a method for accelerating wound healing in a mammal. The method includes identifying an unhealed wound site or partially-healed wound site in a mammal; administering a photosensitizer to the mammal; waiting for a time period wherein the photosensitizer reaches an effective tissue concentration at the wound site; and photoactivating the photosensitizer at the wound site. The dose of photodynamic therapy is selected to stimulate the production of one or more growth factor by cells at the wound site, without causing tissue destruction.

Hasan, Tayyaba (Arlington, MA); Hamblin, Michael R. (Revere, MA); Trauner, Kenneth (Sacramento, CA)

2000-08-22

44

Adjuvant Therapy for Stage II Colon Cancer  

Cancer.gov

In this trial, researchers are using molecular tests to help identify patients who are at high risk for recurrence after colon cancer surgery. High-risk patients will receive adjuvant chemotherapy (drug therapy given after surgery to help suppress cancer recurrence). Some of these patients will also receive bevacizumab. Low-risk patients will be observed but will not receive adjuvant therapy.

45

Adjuvant therapy of resectable rectal cancer  

Microsoft Academic Search

The two conventional treatments for clinically resectable rectal cancer are surgery followed by postoperative combined modality therapy and preoperative combined modality therapy followed by surgery and postoperative chemotherapy. Preoperative therapy (most commonly combined modality therapy) has gained acceptance as a standard adjuvant therapy. The potential advantages of the preoperative approach include decreased tumor seeding, less acute toxicity, increased radiosensitivity due

Bruce D Minsky

2002-01-01

46

Photodynamic effect of functionalized single-walled carbon nanotubes: a potential sensitizer for photodynamic therapy  

NASA Astrophysics Data System (ADS)

Single-walled carbon nanotubes (SWNTs) possess unique physical and chemical properties, which make them very attractive for a wide range of applications. In particular, SWNTs and their composites have shown a great potential for photodynamic therapy (PDT). SWNTs have usually been used for photothermal therapy; herein, the photodynamic effect of two functionalized SWNTs are detected under visible light illumination in vitro and in vivo. The results indicated that the photodynamic effect is not entirely dependent on illumination time, but also on the modification method of the SWNTs. The ability of SWNTs complexes to combine with photodynamic therapy significantly improved the therapeutic efficacy of cancer treatment, and the combined treatment demonstrated a synergistic effect. These findings suggest that the SWNTs composite has great potential as sensitizer for PDT.

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

2014-04-01

47

Photodynamic therapy of genital condylomata in men.  

PubMed

Current treatments for genital condylomata are not completely satisfactory, as they fail to clear lesions in a proportion of patients, and relapses after successful treatment are frequently seen. Photodynamic therapy (PDT) using topical 5-aminolaevulinic acid (5-ALA) has been suggested as a novel treatment option. We performed a small open study using topical 5-ALA and red light (630 nm) in nine men with genital condylomata and a history of at least one previous unsuccessful conventional treatment. Complete cure was achieved in three patients, one of whom experienced a relapse after 3 weeks. Three patients showed partial responses, and three showed no response. Based on the currently available evidence, PDT is a viable treatment option for selected cases that fail to respond to other therapies. PMID:16309481

Herzinger, T; Wienecke, R; Weisenseel, P; Borelli, C; Berking, C; Degitz, K

2006-01-01

48

Role of Photodynamic Therapy for Bone Metastasis  

Microsoft Academic Search

Cancer spread to bone is a significant cause of morbidity in patients with metastatic spread. Metastatic bone disease is also\\u000a the most common cause of destructive lesions in the adult skeleton. With improvements in adjuvant therapies and a decline\\u000a in age-standardized cancer mortality, skeletal metastases are increasingly prevalent in advanced spread (1). As such, there will be greater emphasis on

Shane Burch; Albert J. M. Yee

49

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

50

Photodynamic effects on rabbit auricular veins after photosensitization with porfimer sodium: Implications of the results with respect to the treatment of esophageal varices with photodynamic therapy  

Microsoft Academic Search

Background: There are numerous clinical applications for photodynamic therapy in the GI tract. The principal reason for the wide variety of lesions amenable to photodynamic therapy is the ability to treat large areas of mucosa without the need for complete visualization. This report describes observed hemodynamic and histologic changes in rabbit auricles after photodynamic therapy and the feasibility of photodynamic

Nobuhiko Nagamine; Kenichi Ido; Kouji Saihuku; Toshihiko Higashizawa; Kazunori Ono; Tomosuke Hirasawa; Kentaro Sugano; Ja-Mun Chong

2002-01-01

51

Dosimetry for photodynamic therapy of endometrial tissue  

NASA Astrophysics Data System (ADS)

Hysterectomy is the most common major operation performed in the United States with dysfunctional uterine bleeding as one of the major indications. The clinical needs for simple and safe endometrial destruction are essential. Photodynamic therapy (PDT) may offer a simple and cost effective solution for the treatment of dysfunctional uterine bleeding. The dosimetry is discussed for the case of topical application of photosensitizer. This technique might be the method of preference because undesired side effects such as skin photosensitization that is typical for systemically injected photosensitizers, can be avoided. Effective PDT requires a sufficient amount of light delivered to the targeted tissue in a reasonable period of time. A trifurcated optical applicator consisting of three cylindrical diffusing fibers has been constructed, and this applicator can deliver a typical required optical dose of about 50-100 J/cm2 to the full depth of the endometrium for an exposure time of 10-20 minutes.

Svaasand, Lars O.; Fehr, Mathias K.; Madsen, Sten; Tadir, Yona; Tromberg, Bruce J.

1995-05-01

52

Colonic mucosectomy using laser photodynamic therapy  

SciTech Connect

Photodynamic therapy (PDT) involves photosensitizing tissue and then activating it with monochromatic light, causing necrosis. Precise control of the extent of injury should be possible by varying the energy density of the light applied to the target tissue. We tested the sensitivity of colonic tissue to PDT by injecting 10 mg/kg Photofrin II intraperitoneally in 10 rats. After 24 hr the left colon was opened and cleansed. A 1.0-cm2 area of mucosa was exposed to 630 nm (red) light produced by an argon-pumped dye laser. Pairs of rats were treated with energy densities of either 10, 20, 40, 60, or 80 J/cm2, controlled by varying exposure times. After 48 hr, we sacrificed the rats and fixed, sectioned, and stained the left colons. The depth of injury was measured with an ocular micrometer and expressed as a percentage of normal bowel wall thickness. A curve was fit to the data points by computerized nonlinear regression. The relationship between depth of injury (Y) and energy density (X) was found to fit the equation Y = 1 - aebx, where constants a = 1.15 and b = -0.0353, (R2 = 0.93, P less than 0.001). The relationship between injury and energy density is biphasic, rising rapidly from 0 to 40 J/cm2 and more slowly after this point, suggesting that colonic mucosa is more sensitive to PDT than muscularis, providing a margin of safety against perforation. Bowel perforation did not occur in this study but is predicted by extrapolation for energy densities of 100 J/cm2 or greater. These data indicate that photodynamic colonic mucosectomy is possible.

Fisher, D.G.; Rypins, E.B.; Watson, L.R.; Nelson, J.S.; Berns, M.W.

1989-06-01

53

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.

54

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

55

Photodynamic therapy of malignant mesothelioma of pleura  

NASA Astrophysics Data System (ADS)

Nine patients with malignant pleural mesothelioma underwent extensive surgery followed by intra-operative photodynamic therapy. Two mg/kg Photofrin was given 48 hours prior to surgery. The thoracic cavity and eventual remaining lung were exposed to 15 - 30 Joules/cm2 of 630 nm laser light. Tumor tissue was analyzed by microscopic photometrical techniques. Five patients with mixed or epithelioid tumors with fluorescence intensity > 100 gray level/pixel seemed to benefit from the given therapy. One patient was free of disease 18 months after treatment. Two patients were treated for metastasis after 12 months with no sign of intrathoracic recurrence. Both are still alive, one without further sign of disease 32 months after initial treatment. Two patients presented generalized disease after 9 and 13 months and intrathoracic recurrence several months later. Two patients with poorly differentiated tumors and 2 patients with moderate to highly differentiated tumors, but with fluorescence intensity < 100 gray level/pixel, presented recurrences after 4 months. PDT-efficiency seems to be predicted by the intensity and distribution of drug-induced fluorescence in tumor tissue. PDT may enhance the possibility to achieve complete local tumor control after excision. Multimodal therapeutic approach of local and systemic disease seems mandatory to further improve survival.

Warloe, Trond; Heyerdahl, Helen; Peng, Qian; Hoie, J.; Normann, E.; Solheim, O.; Moan, Johan; Giercksky, Karl-Erik

1994-10-01

56

Photodynamic therapy of malignant mesothelioma of pleura  

NASA Astrophysics Data System (ADS)

Nine patients with malignant pleural mesothelioma underwent extensive surgery followed by intra-operative photodynamic therapy. Two mg/kg Photofrin was given 48 hours prior to surgery. The thoracic cavity and eventual remaining lung were exposed to 15 - 30 Joules/cm2 of 630 nm laser light. Tumor tissue was analyzed by microscopic photometrical techniques. Five patients with mixed or epithelioid tumors with fluorescence intensity > 100 gray level/pixel seemed to benefit from the given therapy. One patient was free of disease 18 months after treatment. Two patients were treated for metastasis after 12 months with no sign of intrathoracic recurrence. Both are still alive, one without further sign of disease 32 months after initial treatment. Two patients presented generalized disease after 9 and 13 months and intrathoracic recurrence several months later. Two patients with poorly differentiated tumors and 2 patients with moderate to highly differentiated tumors, but with fluorescence intensity < 100 gray level/pixel, presented recurrences after 4 months. PDT-efficiency seems to be predicted by the intensity and distribution of drug-induced fluorescence in tumor tissue. PDT may enhance the possibility to achieve complete local tumor control after excision. Multimodal therapeutic approach of local and systemic disease seems mandatory to further improve survival.

Warloe, Trond; Heyerdahl, Helen; Peng, Qian; Hoie, J.; Normann, E.; Solheim, O.; Moan, Johan; Giercksky, Karl-Erik

1995-03-01

57

Optimization of photodynamic therapy using negative pressure.  

PubMed

Abstract Objective: The goal of this study is to demonstrate an alternative procedure to perform topical photodynamic therapy (PDT). Here, we propose the combined use of negative pressure and a 5-Aminolevulinic acid (5-ALA) cream occlusion to increase protoporphyrin IX (PPIX) formation. Background data: PDT using topical 5-ALA as a prodrug and precursor of PPIX has been used in the treatment and diagnosis of different types of cancer and skin diseases. The use of 5-ALA offers many advantages as a localized and non-systemic application, but it shows limitations in relation to skin penetration. Many authors have discussed the limitations of 5-ALA penetration through the skin. The skin penetration of 5-ALA can be optimized using mechanical devices associated with typical PDT procedure. Methods: For this study, 20% 5-ALA cream was applied to a 9?cm(2) area of skin, and an occlusive dressing was placed. The PPIX production was collected at the skin surface, using fluorescence spectroscopy and widefield fluorescence imaging, for 7?h, and after 24?h. Results: We observed that in the presence of negative pressure therapy, the PPIX production, distribution, and elimination are greater and faster than in the control group. The PPIX formation was ?30% in deeper skin layers, quantified by fluorescence spectroscopy analysis, and ?20% in surface skin layers, quantified by widefield fluorescence imaging analysis. Conclusions: Negative pressure induction can also help PDT application in the case of inefficient PPIX production. These results can be useful for optimizing the PDT. PMID:24730611

Menezes, Priscila Fernanda Campos; Requena, Michelle Barreto; Bagnato, Vanderlei Salvador

2014-05-01

58

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

59

Adjuvant therapy for renal cell carcinoma.  

PubMed

In 2006, approximately 38,890 patients in the United States will be diagnosed with kidney tumors. Roughly 90% of those will be renal cell carcinomas (RCCs). Of those patients, 30% will have metastatic disease at the time of diagnosis. An additional 20% to 30% with clinically localized disease at the time of nephrectomy will subsequently develop metastatic disease for which there are few reliable, effective treatments. In 2006, no clinically proven, adjuvant therapy exists for patients at high risk of relapse following definitive surgical therapy. In the past, several strategies have been tried unsuccessfully in the adjuvant setting, including, radiotherapy, chemotherapy, immunotherapy, and hormonal therapy. An improved understanding of the molecular basis of RCC has allowed for a more targeted approach to therapy. Several newer agents, including thalidomide, vitespin (heat shock protein [hsp] 96 vaccine), WX-G250, sorafenib, and sunitinib, are either currently under investigation in the adjuvant setting or being considered for future adjuvant trials. Here, we discuss the past, present, and future of adjuvant therapy for RCC patients at high risk for relapse following definitive surgical therapy. PMID:17045086

Jacobsohn, Kenneth M; Wood, Christopher G

2006-10-01

60

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

61

The use of photodynamic therapy in dermatology.  

PubMed

In dermatology, topical photodynamic therapy (PDT) is a well established treatment modality which has mainly shown to be effective for dermato-oncologic conditions like actinic keratosis, Bowen's disease, in-situ squamous cell carcinoma and superficial basal cell carcinoma. However, a therapeutical benefit of PDT is also evident for inflammatory dermatoses like localized scleroderma, acne vulgaris and granuloma annulare as well as for aesthetic indications like photo aged skin or sebaceous gland hyperplasia. Recent work has been focused on the development and evaluation of topical photosensitizers like the hem precursor 5-aminolevulinic acid or its methyl ester inducing photosensitizing porphyrins. These drugs do not induce strong generalized cutaneous photosensitization like the systemically applied porphyrins or their derivatives. For dermatological purposes incoherent lamps or LED arrays can be used for light activation. Depending on the applied light dose and the concentration of the photosensitizer either cytotoxic effects resulting in tumor destruction or immunomodulatory effects improving the inflammatory conditions occur. Treating superficial oncologic lesions (tumor thickness < 2-3 mm) cure rates achieved by PDT are equal to the cure rates of the respective standard therapeutic procedure. The benefits of PDT are the low level of invasiveness and the excellent cosmetic results after treatment. PMID:20930696

Babilas, P; Szeimies, R M

2010-10-01

62

Photodynamic therapy for retinal capillary hemangioma  

PubMed Central

Purpose To describe the results of photodynamic therapy (PDT) for juxtapapillary and peripheral retinal capillary hemangioma (RCH). Patients and methods Interventional case series of four eyes (four patients) with juxtapapillary RCH and one eye (one patient) with peripheral RCH. Two eyes with juxtapapillary RCH had received two sessions of full-fluence, double-duration PDT; whereas other two eyes had received single session of half-fluence, single-duration PDT. The peripheral RCH was treated with a single session of full-fluence, single-duration PDT. Results Two patients had von Hippel–Lindau disease. Follow-up duration ranged from 4 months to 1 year. Pre-PDT visual acuity (VA) ranged from 20/200 to HM (juxtapapillary RCH) and 20/100 (peripheral RCH). Among the eyes with juxtapapillary RCH, tumor regression with partial resolution of macular edema was noted in two eyes (one eye each with half-fluence and full-fluence PDT), whereas two eyes had no change in tumor size with persistent macular edema. VA remained stable in three eyes and declined in one eye. In an eye with peripheral RCH, regression of tumor and macular edema with VA improvement was noted. Post-PDT complications included epiretinal membrane (one eye) and transient exudative retinal detachment (one eye). Conclusion PDT can be effective in reducing macular edema associated with RCH but this does not always correspond with an improvement in VA especially for juxtapapillary tumors.

Papastefanou, V P; Pilli, S; Stinghe, A; Lotery, A J; Cohen, V M L

2013-01-01

63

Photodynamic therapy of head and neck tumors  

NASA Astrophysics Data System (ADS)

This paper deals with the results of stage 1 clinical trials for sulfated aluminum phthalocyanine (PHS) (Photosens, Russia) in 1994-1996. The results of photodynamic therapy (PDT) of head and neck tumors (HNT), side effects and ways of their correction and prevention, as well as changes in doses of injected photosensitizer (PS), regimes of light irradiation, choice of laser and type of irradiation (surface or interstitial) are discussed. PDT have been provided in 42 patients (93 tumor sites) with different head and neck tumors. Fluorescent diagnostics of tumor, accumulation of PS in tumor, adjacent tissue has been fulfilled. Total 78 PDT sessions have been done. As a source of light we used: quantoscope, solid laser, krypton laser, tunable dye laser, He-Ne-laser. In 38 tumor sites (21 patients) -- 40.8% -- we had clinical response, in 27 tumor sites (16 patients) -- 29.0% -- we had partial response, in 28 tumor sites (8 patients) -- 30.2% -- we had no response. Our experience shows pronounced efficacy of PDT for HNT, except of melanoma. Providing PDT twice with the interval 24 - 72 hours when retention of PS is sufficient for treatment, did additive effect to the tumor, but didn't increase adjacent tissue damage.

Vakoulovskaya, Elena G.; Shental, Victor V.; Abdoullin, N. A.; Kuvshinov, Yury P.; Tabolinovskaia, T. D.; Edinak, N. J.; Poddubny, Boris K.; Lioubaev, V. L.; Boikov, V. P.; Kondratjeva, T. T.; Meerovich, Gennadii A.; Stratonnikov, Alexander A.; Linkov, Kirill G.; Agafonov, Valery V.

1996-12-01

64

Integrating spheres for improved skin photodynamic therapy  

NASA Astrophysics Data System (ADS)

The prescribed radiant exposures for photodynamic therapy (PDT) of superficial skin cancers are chosen empirically to maximize the success of the treatment while minimizing adverse reactions for the majority of patients. They do not take into account the wide range of tissue optical properties for human skin, contributing to relatively low treatment success rates. Additionally, treatment times can be unnecessarily long for large treatment areas if the laser power is not sufficient. Both of these concerns can be addressed by the incorporation of an integrating sphere into the irradiation apparatus. The light fluence rate can be increased by as much as 100%, depending on the tissue optical properties. This improvement can be determined in advance of treatment by measuring the reflectance from the tissue through a side port on the integrating sphere, allowing for patient-specific treatment times. The sphere is also effective at improving beam flatness, and reducing the penumbra, creating a more uniform light field. The side port reflectance measurements are also related to the tissue transport albedo, enabling an approximation of the penetration depth, which is useful for real-time light dosimetry.

Glennie, Diana L.; Farrell, Thomas J.; Hayward, Joseph E.; Patterson, Michael S.

2010-09-01

65

Photodynamic therapy of breast cancer with photosense  

NASA Astrophysics Data System (ADS)

Photodynamic Therapy (PDT) using photosensitizer Photosense (PS) in dose 0.5 mg per kg of body weight have been provided in 24 patients with breast cancer. In 22 patients with T1-T2N0M0 primary tumor was treated as the preoperative treatment, radical mastectomy has been fulfilled 7-10 days after PDT with subsequent histological examination. 2 patients had recurrencies of breast cancer with lymph node metastases after radiotherapy. Fluorescent diagnostics of tumor, accumulation of PS in tumor, adjacent tissue, skin before and during PDT was fulfilled with spectranalyzer LESA-01. We used semiconductive laser for PDT - ? = 672+2nm, P=1,5 W, interstitial irradiation 2-24 hours after PS injection has been done in light dose 150-200 J/cm3, 1-3 irradiations with interval 24-48 hours and total light dose 400-600 J/cm3 depending mostly of size and fluorescent data. Partial regression of tumor with pathomorphosis of 2-4 degrees has been found in 19 cases. Our experience shows pronounced efficacy of PDT for treating breast cancer as preoperative modality and as palliation in cases of recurrencies.

Vakoulovskaya, Elena G.; Shental, Victor V.; Oumnova, Loubov V.; Vorozhcsov, Georgiu N.

2003-06-01

66

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

67

Photodynamic therapy in lung and gastrointestinal cancers.  

PubMed

Twelve central bronchial carcinoma patients and two gastrointestinal (GI) tract (oesophageal and colonic) early-stage cancer patients were treated with photodynamic therapy (PDT). Haematoporphyrin (HP/5, Jacopo Monico, Italy) at a dose of 5 mg kg-1 body weight was used as photosensitizer. Laser light at 628.2-630 nm generated by two different laser systems (gold vapour laser (I.P. Optics, Sofia, Bulgaria) in lung cancer cases and an argon dye laser system (Spectra Physics, Mountain View, U.S.A.) in GI tract cancers) was used. Lung cancers were irradiated 48 h after drug administration and GI tract cancers were irradiated 72 h after infusion of the photosensitizer. Both tumour sites were treated with a total energy dose in the range 350-600 J cm-2. Efficiency of PDT in lung cancer was evaluated by X-rays and endoscopic and functional respiratory tests for bronchial de-obstruction. Complete remission after PDT of GI tract cancers was considered to be tumour eradication (histologically and cytologically proved) and a tumour-free interval of at least 12 months. PMID:2121932

Karanov, S; Kostadinov, D; Shopova, M; Kurtev, P

1990-06-01

68

Modelling fluorescence in clinical photodynamic therapy.  

PubMed

Understanding the interactions of non-ionizing radiation with living organisms has been the focus of much research over recent decades. The complex nature of these interactions warrants development of theoretical and experimental studies to gain an insight into predicting and monitoring the success of photodynamic therapy (PDT) protocols. There is a major impetus towards evidence-based recommendations for patient diagnosis, treatment and management. Knowledge of the biophysical aspects of PDT is important for improving dosimetry protocols. Fluorescence in clinical PDT may be used to detect and diagnose pre-malignant and malignant conditions, while photobleaching can monitor changes in fluorescence during treatment. Combining empirical fluorescence photobleaching clinical data with computational modelling enables clinical PDT dosimetry protocols to be investigated with a view to optimising treatment regimes. We will discuss how Monte Carlo radiation transfer (MCRT) modelling has been intercalated in the field of fluorescence detection and PDT. In this paper we highlight important aspects of basic research in PDT by reporting on the current utilisation of fluorescence in clinical PDT from both a clinical and theoretical perspective. Understanding and knowledge of light propagation in biological tissue from these perspectives should have a positive impact on treatment planning. PMID:23128146

Valentine, Ronan M; Ibbotson, Sally H; Wood, Kenny; Brown, C Tom A; Moseley, Harry

2013-01-01

69

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

70

Photodynamic therapy in dermatology--an update.  

PubMed

Topical photodynamic therapy (PDT) is a well-established treatment modality which has mainly shown to be effective for dermatooncologic conditions like actinic keratoses (AK), Bowen's disease, in situ squamous cell carcinoma and superficial basal cell carcinoma (BCC). However, a therapeutical benefit of PDT is also evident for inflammatory dermatoses like localized scleroderma, acne vulgaris and granuloma annulare. Recent work has been focused on the development and evaluation of topical photosensitizers like the heme precursor 5-aminolevulinic acid (5-ALA) or its methyl ester (methyl aminolevulinate) inducing photosensitizing porphyrins. These drugs do not induce strong generalized cutaneous photosensitization like the systemically applied porphyrins or their derivatives. For dermatological purposes, incoherent lamps or light-emitting diode arrays can be used for light activation. Depending on the applied light dose and the concentration of the photosensitizer either cytotoxic effects resulting in tumor destruction or immunomodulatory effects improving the inflammatory conditions occur. Treating superficial oncologic lesions (tumor thickness <2-3 mm) cure rates achieved by PDT are equal to the cure rates of the respective standard therapeutic procedure. The benefits of PDT are the low level of invasiveness and the excellent cosmetic results after treatment. PMID:15888131

Babilas, Philipp; Karrer, Sigrid; Sidoroff, Alexis; Landthaler, Michael; Szeimies, Rolf-Markus

2005-06-01

71

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

72

[Adjuvant therapy of colon carcinoma].  

PubMed

In patients with stage III carcinoma of the colon, adjuvant chemotherapy is indicated after R0 resection. No age limitations exist. Combination chemotherapy with FOLFOX4 or (if oxaliplatin is contraindicated) monotherapy with a fluoropyrimidine, preferably capecitabine, can be regarded as the standard treatment. Because of its unfavorable toxicity profile, the 5-FU/folic acid bolus scheme (the Mayo scheme) should no longer be used, and combinations including irinotecan also do not play a part in colon carcinoma. The combination XELOX (oxaliplatin + capecitabine) is currently being studied in phase III trials. Data on the efficacy of the targeted drugs bevacizumab and cetuximab cannot be expected until at least 2010/2011. It is important that adjuvant treatment be started in a timely manner, within 8 weeks of surgery. As far as stage II disease is concerned, adjuvant chemotherapy analogous to that for stage III should be considered in high-risk patients (T4, emergency surgery, tumor perforation/tear, < 12 lymph nodes examined). The evidence for this recommendation is, however, based mainly on unplanned subgroup analyses of randomized trials. That low-risk stage II patients can also profit from adjuvant treatment was shown in the QUASAR trial(significant survival benefit of 3.6%), so this group of patients can be offered chemotherapy containing 5-FU. For treatments involving oxaliplatin in low-risk patients there is currently insufficient evidence. PMID:19033700

Trarbach, Tanja; Kubicka, Stefan; Hacker, Ulrich; Ridwelski, Karsten; Reinacher-Schick, Anke

2008-01-01

73

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

74

Selective tumor destruction with photodynamic therapy: exploitation of photodynamic thresholds  

NASA Astrophysics Data System (ADS)

The uptake and distribution of the photosensitizer aluminum sulphonated phthalocyanine (AlSPc) has been studied. In a variety of experimentally induced gastrointestinal tumors the photosensitizer is retained between 24 - 48 hours after intravenous administration compared with the adjacent normal tissue in which the tumor arose. However, the maximum tumor-to- normal-tissue ratio was only 2:1. Quantitative fluorescence photometry using digital image processing, with a CCD camera and helium neon laser, was used to probe the microscopic localization of the photosensitizer in tissue sections of tumor and normal tissue. Selective localization of the photosensitizer was nonspecific in tumor stroma and there was never any significant difference between normal and neoplastic cells. Exploitation of the small differences in photosensitizer concentration, photodynamic threshold effects, and photosensitizer photodegration allows up to 2 mm of selective tumor damage to be produced in a tumor, when a similar light dose will produce no damage in adjacent normal tissue. However, selective eradication of a tumor without adjacent tissue damage will not be possible by using these methods. This paper reviews this previously reported data.

Barr, Hugh

1991-11-01

75

The novel polymeric systems for photodynamic therapy technique.  

PubMed

Photodynamic therapy (PDT) is a medical treatment in which a combination of a photosensitizing drug and visible light causes destruction of selected cells. Over the past two decades, photodynamic therapy has enjoyed a period of laboratory and in the clinic. Although still widely considered to be an experimental technique, its status and value within modern clinical practice continues to grow. The PDT field has, to date, been dominated by a small number of pharmaceutical companies inhabited almost exclusively by clinicians and those involved in fundamental scientific research. True pharmaceutical formulation development has been limited, to some extent, by financial constraints. If PDT is to realize its undoubted potential in clinical practice it is important that awareness of the need for appropriate photosensitizer delivery systems is raised. Accordingly, this article deals with the innovations pertaining to drug delivery systems for photodynamic therapy as disclosed in recent patent literature. PMID:24440522

Saboktakin, Mohammad Reza; Tabatabaee, Roya Mahdavi

2014-04-01

76

Adjuvant Therapy in Pancreatic Cancer  

Microsoft Academic Search

Pancreatic cancer is one of the major causes of cancer death in Europe with a 5-year survival rate of less than 5%. Although surgery cannot guarantee a cure, the 5-year survival does improve to around 10% following resection and increases to 20–30% with adjuvant chemotherapy. The European Study Group for Pancreatic Cancer (ESPAC) 1 trial was the first adequately powered,

Amy Thomas; Khaled Dajani; John P. Neoptolemos; Paula Ghaneh

2010-01-01

77

Multiple laser irradiation of ORL organ tumors in photodynamic therapy  

NASA Astrophysics Data System (ADS)

The results of ORL organ tumor photodynamic therapy with the use of Phtalocyanine Al and multiple sequences of laser irradiation are presented. The possibility of decreasing the concentration of the preparation in accordance with laser irradiation tactics was investigated. The process of tissue necrotization for big and difficult tumors for laser irradiation access has been investigated. The estimation of photosensitizer distribution character for local injection has been carried out. The principal possibility of using local injection of photosensitizer for photodynamic therapy has been shown.

Shental, V. V.; Edynak, N. E.; Abdulin, N. A.; Kuvshinov, Yury P.; Poddubny, B. K.; Tabolinovskaya, T. D.; Loschenov, Victor B.; Poleshkin, P. V.; Luk'yanets, E. A.

1995-01-01

78

Treatment of verrucae vulgaris and molluscum contagiosum with photodynamic therapy.  

PubMed

The use of 5-aminolevulinc acid photodynamic therapy in the treatment of recalcitrant verrucae vulgaris and in the treatment of recalcitrant molluscum contagiosum has been shown to substantially reduce the lesion count and severity. Clinical research published in the medical literature and personal experience of both of the authors support the use of 5-aminolevulinc acid photodynamic therapy in appropriate individuals with recalcitrant verrucae vulgaris and molluscum contagiosum lesions. This article reviews the medical literature and identifies the various lasers and lights sources used to treat these conditions. PMID:17126744

Gold, Michael H; Moiin, Ali

2007-01-01

79

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

80

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

81

Photodynamic therapy by in situ nonlinear photon conversion  

NASA Astrophysics Data System (ADS)

In photodynamic therapy, light is absorbed by a therapy agent (photosensitizer) to generate reactive oxygen, which then locally kills diseased cells. Here, we report a new form of photodynamic therapy in which nonlinear optical interactions of near-infrared laser radiation with a biological medium in situ produce light that falls within the absorption band of the photosensitizer. The use of near-infrared radiation, followed by upconversion to visible or ultraviolet light, provides deep tissue penetration, thus overcoming a major hurdle in treatment. By modelling and experiment, we demonstrate activation of a known photosensitizer, chlorin e6, by in situ nonlinear optical upconversion of near-infrared laser radiation using second-harmonic generation in collagen and four-wave mixing, including coherent anti-Stokes Raman scattering, produced by cellular biomolecules. The introduction of coherent anti-Stokes Raman scattering/four-wave mixing to photodynamic therapy in vitro increases the efficiency by a factor of two compared to two-photon photodynamic therapy alone, while second-harmonic generation provides a fivefold increase.

Kachynski, A. V.; Pliss, A.; Kuzmin, A. N.; Ohulchanskyy, T. Y.; Baev, A.; Qu, J.; Prasad, P. N.

2014-06-01

82

IL-6 Potentiates Tumor Resistance to Photodynamic Therapy (PDT)  

PubMed Central

Background and Objective Photodynamic therapy (PDT) is an anticancer modality approved for the treatment of early disease and palliation of late stage disease. PDT of tumors results in the generation of an acute inflammatory response. The extent and duration of the inflammatory response is dependent upon the PDT regimen employed and is characterized by rapid induction of proinflammatory cytokines, such as IL-6, and activation and mobilization of innate immune cells. The importance of innate immune cells in long-term PDT control of tumor growth has been well defined. In contrast the role of IL-6 in long-term tumor control by PDT is unclear. Previous studies have shown that IL-6 can diminish or have no effect on PDT antitumor efficacy. Study Design/Materials and Methods In the current study we used mice deficient for IL-6, Il6?/?, to examine the role of IL-6 in activation of antitumor immunity and PDT efficacy by PDT regimens known to enhance antitumor immunity. Results Our studies have shown that elimination of IL-6 had no effect on innate cell mobilization into the treated tumor bed or tumor draining lymph node (TDLN) and did not affect primary antitumor T-cell activation by PDT. However, IL-6 does appear to negatively regulate the generation of antitumor immune memory and PDT efficacy against murine colon and mammary carcinoma models. The inhibition of PDT efficacy by IL-6 appears also to be related to regulation of Bax protein expression. Increased apoptosis was observed following treatment of tumors in Il6?/? mice 24 hours following PDT. Conclusions The development of PDT regimens that enhance antitumor immunity has led to proposals for the use of PDT as an adjuvant treatment. However, our results show that the potential for PDT induced expression of IL-6 to enhance tumor survival following PDT must be considered.

Brackett, Craig M.; Owczarczak, Barbara; Ramsey, Kimberley; Maier, Patricia G.; Gollnick, Sandra O.

2013-01-01

83

[Palliative locoregional therapy for hilar cholangiocarcinoma: photodynamic therapy and brachytherapy].  

PubMed

In hilar cholangiocarcinoma, only 20-30% of the patients are candidates for curative surgical resection, leaving the majority with merely palliative treatment options. Since the natural history of hilar cholangiocarcinoma is dominated by local complications rather than metastatic disease, local palliative treatment seems a reasonable option. Here, endoluminal photodynamic therapy has emerged as a promising treatment with several prospective observational studies and 2 prospective randomised studies published which included nearly 200 patients. With low complication rate and morbidity, PDT achieves an increased median survival as well as an increased quality of life even in patients with reduced performance status. Radiotherapy is an alternative local treatment option applied as brachytherapy, external beam radiotherapy or combined modality treatment. To date, however, sufficient data from controlled clinical trials are lacking, thus palliative radiotherapy has to be considered an experimental treatment option. PMID:17724637

Dumoulin, F L; Horst, E; Sauerbruch, T; Gerhardt, T

2007-08-01

84

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

85

Optical coherence tomography guided retreatment of photodynamic therapy  

Microsoft Academic Search

Aim: To evaluate the results of a retreatment modality of photodynamic therapy (PDT) based on optical coherence tomography (OCT) and fluorescein angiography (FA). To quantify the effect of PDT with the help of measurement of the retinal thickness.Methods: Eyes with predominantly classic subfoveal choroidal neovascularisation (CNV) due to age related macular degeneration were included. PDT was performed every three months,

I Krebs; S Binder; U Stolba; K Schmid; C Glittenberg; W Brannath; A Goll

2005-01-01

86

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

87

MEASUREMENT OF REACTIVE OXYGEN SPECIES AFTER PHOTODYNAMIC THERAPY IN VITRO  

Microsoft Academic Search

A b s t r a c t Photodynamic therapy (PDT) is an emerging modality for the treatment of neoplastic and non- neoplastic diseases. It is based on the use of a sensitiser, which is localised in target tissue, light, and molecular oxygen. Sensitisers are activated with the appropriate wavelength of light and then are excited to the long-lived triplet

88

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

89

In Vivo Optical Imaging of Molecular Responses to Photodynamic Therapy  

Microsoft Academic Search

Photodynamic therapy activates a variety of molecular responses, which are considered important for long-term tumor control. Using recently developed antibody labeling technique that enables high resolution, high contrast imaging of cell populations in vivo, we demonstrate the ability to visualize these responses using confocal fluorescence imaging in superficial tumors.

Soumya Mitra; Thomas H. Foster

90

Online electrochemical monitoring of nitric oxide during photodynamic therapy  

Microsoft Academic Search

Photodynamic therapy (PDT), as a novel treatment modality, is based on the use of a photosensitizing agent with an excitation light source for the treatment of various malignancies. Its effect is mediated through reactive oxygen species and nitric oxide (NO), which are shown to be present in apoptosis. Individual differences among patients and even in different areas of the same

Tayfun Dalbasti; Sedat Cagli; Emrah Kilinc; Nezih Oktar; Mehmet Ozsoz

2002-01-01

91

Preliminary results of photodynamic therapy for recurrent nasopharyngeal carcinoma  

Microsoft Academic Search

Photodynamic therapy (PDT) is a promising new modality in the treatment of cancer. In Hong Kong where nasopharyngeal carcinoma (NPC) is endemic, radiotherapy has been the primary treatment of choice. For recurrent disease after radiotherapy, there is no effective treatment. This latter report summarizes our initial experience in using PDT for these patients. Twelve patients (three females and nine males)

M. C. F. Tong; C. A. Hasselt; J. K. S. Woo

1996-01-01

92

Photodynamic therapy for intraepithelial neoplasia of the lower genital tract.  

PubMed

Photodynamic Diagnosis (PDD) and Therapy (PDT) are modern methods which are evaluated in different fields in gynaecology. PDT has been successfully evaluated in human papillomavirus-related (HPV) genital dysplasia like CIN and VIN. The aim of this review is to give an overview about current applications. PMID:20230987

Soergel, Philipp; Hillemanns, Peter

2010-03-01

93

Photodynamic therapy of Porphyromonas gingivalis via liposome-encapsulated sensitizers.  

PubMed

Photodynamic therapy exploits the light-activation of a photosensitizer to cause cytotoxicity. Liposomes can be used to deliver hydrophobic photosensitizers to bacteria. Positively charged dioleoyltrimethylammoniumpropane:palmitoyloleoylphosphatidylcholine (1:1) liposomes bound quantitatively to the periodontal pathogen, Porphyromonas gingivalis. Following illumination, free and liposomal zinc phthalocyanine reduced the colony-forming unit (CFU) to 65 percent and 23 percent of controls, respectively. Thus, localization of the photosensitizer at the surface of bacteria via liposome binding enhanced the photodynamic cytotoxicity of zinc phthalocyanine. PMID:24341134

Ko, Alex; Yee, Michael; Skupin-Mrugalska, Paulina; Düzgünes, Nejat

2013-11-01

94

Photodynamic Therapy for the Endodontic Treatment of a Traumatic Primary Tooth in a Diabetic Pediatric Patient  

PubMed Central

Conservation of deciduous teeth with pulp alterations caused by caries or trauma is a major therapeutic challenge in pediatric dentistry. It is essential that the sanitizers used in root canal procedures perform well in eliminating bacteria. Antimicrobial photodynamic therapy (PDT) is an emerging and promising adjuvant therapy for endodontic treatment in an attempt to eliminate microorganisms persistent after chemomechanical preparation. This paper reports the case of a five-year-old male with type I diabetes mellitus, presenting the need for pulp therapy in maxillary primary left central incisor due to injury. The proposed treatment included the use of PDT for decontamination of root canals with the application of 50 ?g/mL of methylene blue dye for 3-5 minutes and 40 J/cm2 as energy density, taking into account the need for tissue penetration and effec-tiveness of PDT inside the dentinal tubules.

de Sant'Anna, Giselle

2014-01-01

95

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

96

Photodynamic therapy for focal ablation of the prostate.  

PubMed

Although in early stages of clinical development, photodynamic therapy (PDT) shows promise in delivering focal treatment of both primary and post-radiotherapy prostate cancer. This article will review the mechanism of action of PDT, previous research using PDT for treating prostate cancer including the development of newer vascular-acting photosensitizers, and the potential advantages and disadvantages of PDT in delivering focal therapy. PMID:20454966

Arumainayagam, Nimalan; Moore, C M; Ahmed, Hashim U; Emberton, M

2010-10-01

97

In vivo measurement of fluorescence emission in the human prostate during photodynamic therapy  

Microsoft Academic Search

Among the challenges to the clinical implementation of photodynamic therapy (PDT) is the delivery of a uniform photodynamic dose to induce uniform damage to the target tissue. As the photodynamic dose depends on both the local sensitizer concentration and the local fluence rate of treatment light, knowledge of both of these factors is essential to the delivery of uniform dose.

Jarod C. Finlay; Timothy C. Zhu; Andreea Dimofte; Diana Stripp; S. B. Malkowicz; Richard Whittington; Jeremy Miles; Eli Glatstein; Stephen M. Hahn

2005-01-01

98

Adjuvant Endocrine Therapy in Premenopausal Patients  

PubMed Central

Summary Endocrine adjuvant therapy is the best-described molecular targeted treatment and should therefore be used for all patients with endocrine-responsive breast cancer. Ta-moxifen for 5 years is standard of care and has proven efficacy in premenopausal patients. The combination of tamoxifen with ovarian function suppression and/or chemotherapy has been extensively tested, and some controversial approaches are used in clinical practice. Cessation or suppression of ovarian function appears to be beneficial for premenopausal patients. Particularly for premenopausal women with highly endocrine-responsive disease and/or low risk for relapse, the additional benefit of cytotoxic chemotherapy may be minor or nonexistent. While the use aromatase inhibitors is investigated in clinical trials, their application outside an academic trial setting cannot be recommended based on first available results. In contrast, the use of adjuvant bispho-sphonates may offer another strategy of further improving clinical outcomes in this important patient subgroup.

Gnant, Michael

2008-01-01

99

Adjuvant Endocrine Therapy in Premenopausal Patients.  

PubMed

Endocrine adjuvant therapy is the best-described molecular targeted treatment and should therefore be used for all patients with endocrine-responsive breast cancer. Ta-moxifen for 5 years is standard of care and has proven efficacy in premenopausal patients. The combination of tamoxifen with ovarian function suppression and/or chemotherapy has been extensively tested, and some controversial approaches are used in clinical practice. Cessation or suppression of ovarian function appears to be beneficial for premenopausal patients. Particularly for premenopausal women with highly endocrine-responsive disease and/or low risk for relapse, the additional benefit of cytotoxic chemotherapy may be minor or nonexistent. While the use aromatase inhibitors is investigated in clinical trials, their application outside an academic trial setting cannot be recommended based on first available results. In contrast, the use of adjuvant bispho-sphonates may offer another strategy of further improving clinical outcomes in this important patient subgroup. PMID:20824025

Gnant, Michael

2008-01-01

100

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

101

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

102

Development of Low-Cost Photodynamic Therapy Device  

Microsoft Academic Search

Photodiagnosis and photodynamic therapy of non-melanoma skin cancers using delta-aminolevulinic acid\\/protoporphyrin IX (5-ALA\\/PpIX) give a combined application with broadest dissemination in the current clinical practice. The problems with using of lasers as light sources are the expenses associated with the operation of these types of installations. This is why we test the capability of cheaper sources - light-emitting diodes at

N. Momchilov; I. Bliznakova; E. Borisova; P. Troyanova

2007-01-01

103

Glycan-Targeted Virus-like Nanoparticles for Photodynamic Therapy  

PubMed Central

Virus-like particles (VLPs) have proven to be versatile platforms for chemical and functionalization for a variety of purposes in biomedicine, catalysis, and materials science. We here the simultaneous modification of the bacteriophage Q? VLP with a metalloporphyrin derivative photodynamic therapy and a glycan ligand for specific targeting of cells bearing the CD-22 receptor. This application benefits from the presence of the targeting function and the delivery of a high local concentration of singlet oxygen-generating payload.

Rhee, Jin-Kyu; Baksh, Michael; Nycholat, Corwin; Paulson, James C.; Kitagishi, Hiroaki; Finn, M.G.

2012-01-01

104

Implicit and explicit dosimetry in photodynamic therapy: a New paradigm  

Microsoft Academic Search

Dosimetry for photodynamic therapy (PDT) is becoming increasingly complex as more factors are identified which may influence\\u000a the effectiveness of a given treatment. The simple prescription of a PDT treatment in terms of the administered photosensitizer\\u000a dose, the incident light and the drug-light time interval does not account for patient-to-patient variability in either the\\u000a photosensitizer uptake, tissue optical properties or

B. C. Wilson; M. S. Patterson; L. Lilge

1997-01-01

105

Photodynamic therapy of tumours and other diseases using porphyrins  

Microsoft Academic Search

Photodynamic therapy (PDT) with porphyrins and red light (620–630 nm) is finding increasing clinical application for both\\u000a the eradication of relatively small tumours and the palliation of inoperable or obstructive tumours. PDT also shows some promise\\u000a for the sterilization of the tumour bed after surgical removal of neoplastic masses. Several porphyrins have been found to\\u000a be accumulated and retained by

John D. Spikes; Giulio Jori

1987-01-01

106

Epigenetic remodeling combined with photodynamic therapy elicits anticancer immune responses  

PubMed Central

Photodynamic therapy has been shown to induce strong immunity against tumor cells expressing exogenous tumor-associated antigens (TAAs), including P1A antigen. Cancer cells can evade the immune system by epigenetic silencing of TAAs, while DNA methyltransferase inhibitors, such as 5-aza-2’-deoxycytidine (5-aza-dC) can restore the expression of silenced or downregulated TAA. Thus, epigenetic remodeling with 5-aza-dC combined with PDT can elicit robust and durable antitumor immunity.

Wachowska, Malgorzata; Gabrysiak, Magdalena; Golab, Jakub

2014-01-01

107

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

108

Simultaneous two-photon excitation of photodynamic therapy agents  

SciTech Connect

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 1 and type 2 photodynamic therapy (PDT) agents are examined.

Wachter, E.A.; Fisher, W.G. [Oak Ridge National Lab., TN (United States)]|[Photogen, Inc., Knoxville, TN (United States); Partridge, W.P. [Oak Ridge National Lab., TN (United States); Dees, H.C. [Photogen, Inc., Knoxville, TN (United States); Petersen, M.G. [Univ. of Tennessee, Knoxville, TN (United States). College of Veterinary Medicine

1998-01-01

109

Photodynamic therapy in the treatment of basal cell carcinoma.  

PubMed

Photodynamic therapy (PDT) is a medical procedure based on the activation of the molecules of various exogenous or endogenous chemical substances called photosensitizers by a light source emitting radiation of an adequate wavelength, usually situated in the visible spectrum; photosensitizers are chemical compounds bearing the capacity to selectively concentrate in the neoplastic cells. The energy captured by the molecules of these substances pervaded in the tumor cells is subsequently discharged in the surrounding tissue, triggering certain photodynamic reactions that result in the destruction of the tumor. The procedure is applicable in numerous medical fields. Skin basal cell carcinoma (BCC), the most frequent type of cancer of the human species, is a cutaneous tumor that responds very well to this innovative treatment method. By reviewing numerous recent studies in the field, this article aims to present the role and the indications of photodynamic therapy in the management of basal cell carcinoma, as well as the most important results achieved so far by this therapy in the field of dermato-oncology. PMID:23599819

Matei, C; Tampa, M; Poteca, T; Panea-Paunica, G; Georgescu, S R; Ion, R M; Popescu, S M; Giurcaneanu, C

2013-03-15

110

Photodynamic therapy in the treatment of basal cell carcinoma  

PubMed Central

Photodynamic therapy (PDT) is a medical procedure based on the activation of the molecules of various exogenous or endogenous chemical substances called photosensitizers by a light source emitting radiation of an adequate wavelength, usually situated in the visible spectrum; photosensitizers are chemical compounds bearing the capacity to selectively concentrate in the neoplastic cells. The energy captured by the molecules of these substances pervaded in the tumor cells is subsequently discharged in the surrounding tissue, triggering certain photodynamic reactions that result in the destruction of the tumor. The procedure is applicable in numerous medical fields. Skin basal cell carcinoma (BCC), the most frequent type of cancer of the human species, is a cutaneous tumor that responds very well to this innovative treatment method. By reviewing numerous recent studies in the field, this article aims to present the role and the indications of photodynamic therapy in the management of basal cell carcinoma, as well as the most important results achieved so far by this therapy in the field of dermato-oncology.

Matei, C; Tampa, M; Poteca, T; Panea-Paunica, G; Georgescu, SR; Ion, RM; Popescu, SM; Giurcaneanu, C

2013-01-01

111

Novel flexible light diffuser and irradiation properties for photodynamic therapy.  

PubMed

Many current light diffusers for photodynamic therapy are inflexible, and the applied light dose is difficult to adjust during treatment, especially on complex body surfaces. A thin and flexible luminous textile is developed using plastic optical fibers as a light distributor. The textile diffuser is evaluated for flexibility, irradiance, brightness distribution, and temperature rise with a 652-nm laser set to 100 mW. The bending force of the textile diffuser resembles a defined optical film. On the textile surface, an average output power of 3.6+/-0.6 mWcm(2) is measured, corresponding to a transmission rate of 40+/-3.8% on an area of 11 cm(2). Aluminum backing enhances the irradiance to the face (treatment side). The measured brightness distribution seems to lie within a range similar to other photodynamic therapy (PDT) devices. A power setting of 100 mW increases the temperature of the textile diffuser surface of up to 27 degrees C, and 1 W raises the temperature above 40 degrees C. Results confirm that the flexible textile diffuser supplies suitable radiation for low fluence rate photodynamic therapy on an area of several cm(2). PMID:17614732

Selm, Baerbel; Rothmaier, Markus; Camenzind, Martin; Khan, Tania; Walt, Heinrich

2007-01-01

112

Tumor vasculature targeted photodynamic therapy for enhanced delivery of nanoparticles.  

PubMed

Delivery of nanoparticle drugs to tumors relies heavily on the enhanced permeability and retention (EPR) effect. While many consider the effect to be equally effective on all tumors, it varies drastically among the tumors' origins, stages, and organs, owing much to differences in vessel leakiness. Suboptimal EPR effect represents a major problem in the translation of nanomedicine to the clinic. In the present study, we introduce a photodynamic therapy (PDT)-based EPR enhancement technology. The method uses RGD-modified ferritin (RFRT) as "smart" carriers that site-specifically deliver (1)O2 to the tumor endothelium. The photodynamic stimulus can cause permeabilized tumor vessels that facilitate extravasation of nanoparticles at the sites. The method has proven to be safe, selective, and effective. Increased tumor uptake was observed with a wide range of nanoparticles by as much as 20.08-fold. It is expected that the methodology can find wide applications in the area of nanomedicine. PMID:24806291

Zhen, Zipeng; Tang, Wei; Chuang, Yen-Jun; Todd, Trever; Zhang, Weizhong; Lin, Xin; Niu, Gang; Liu, Gang; Wang, Lianchun; Pan, Zhengwei; Chen, Xiaoyuan; Xie, Jin

2014-06-24

113

Diblock copolymers to deliver hydrophobic photosensitizers for photodynamic therapy  

NASA Astrophysics Data System (ADS)

Polymeric micelles, self-assemblies of block copolymers, are emerging as attractive drug delivery systems for hydrophobic photodynamic sensitizers. Recent advances in the formulation of photosensitizers for photodynamic therapy (PDT) with diblock copolymers are presented. This paper reviews the main characteristics of existing drug-loading micelles with diblock copolymers, including loading efficiency, particle size and morphology, stability, cellular uptake, subcellular distribution and therapeutic efficiency. The results indicate that diblock polymeric micelles are potentially useful for the delivery and release of hydrophobic photosensitizers in PDT. While significant progress has been achieved, many challenges remain in elucidating the detailed internalization mechanisms of the micelles and resulting mechanisms for enhanced photocytotoxicity. Some critical issues for diblock copolymers to deliver hydrophobic photosensitizers for PDT are highlighted.

Li, Buhong

2007-10-01

114

Positively charged calcium phosphate/polymer nanoparticles for photodynamic therapy.  

PubMed

The charge of nanoparticles influences their ability to pass through the cellular membrane, and a positive charge should be beneficial. The negative charge of calcium phosphate nanoparticles with an inner shell of carboxymethyl cellulose (CMC) was reversed by adding an outer shell of poly(ethyleneimine) (PEI) into which the photoactive dye 5,10,15,20-tetrakis(3-hydroxyphenyl)-porphyrin (mTHPP) was loaded. The aqueous dispersion of the nanoparticles was used for photodynamic therapy with HT29 cells (human colon adenocarcinoma cells), HIG-82 cells (rabbit synoviocytes), and J774A.1 cells (murine macrophages). A high photodynamic activity (killing) together with a very low dark toxicity was observed for HIG-82 and for J774.1 cells at 2 microM dye concentration. The killing efficiency was equivalent to the pure photoactive dye that, however, needs to be administered in alcoholic solution. PMID:19924519

Klesing, J; Wiehe, A; Gitter, B; Gräfe, S; Epple, M

2010-03-01

115

Fluorescence-guided resections and photodynamic therapy for malignant gliomas using 5-aminolevulinic acid  

NASA Astrophysics Data System (ADS)

Oral application of 20 mg/kg bw of 5-aminolevulinic acid results in a highly specific accumulation of fluorescent and phototoxic Protoporphyrin IX in malignant glioma tissue. Surgical removal with fluorescence guidance is studied in a phase III clinical trial, adjuvant Photodynamic Therapy (PDT) to the surgical cavity is in phase II and for interstitial PDT of recurrent gliomas, a phase I/II study has started. Fluorescence guided resections have been shown to be safe and effective in augmenting neurosurgical removal of malignant gliomas in 52 consecutive patients. Intra-operative fluorescence spectroscopy showed statistically significant higher sensitizer accumulation in vital brain tumor versus the infiltration zone and in the infiltration zone versus adjacent normal brain, which contained very little PPIX. This is promisingly exploited for PDT - both to the surgical cavity by surface irradiation and for stereotactically guided interstitial irradiation.

Stepp, Herbert G.; Beck, Tobias; Beyer, Wolfgang; Pongratz, Thomas; Sroka, Ronald; Baumgartner, Reinhold; Stummer, Walter; Olzowy, Bernhard; Mehrkens, Jan H.; Tonn, Joerg C.; Reulen, Hans J.

2005-04-01

116

Cancer treatment by photodynamic therapy combined with NK-cell-line-based adoptive immunotherapy  

NASA Astrophysics Data System (ADS)

Treatment of solid cancers by photodynamic therapy (PDT) triggers a strong acute inflammatory reaction localized to the illuminated malignant tissue. This event is regulated by a massive release of various potent mediators which have a profound effect not only on local host cell populations, but also attract different types of immune cells to the treated tumor. Phagocytosis of PDT-damaged cancerous cells by antigen presenting cells, such as activated tumor associated macrophages, enables the recognition of even poorly immunogenic tumors by specific immune effector cells and the generation of immune memory populations. Because of its inflammatory/immune character, PDT is exceptionally responsive to adjuvant treatments with various types of immunotherapy. Combining PDT with immuneactivators, such as cytokines or other specific or non-specific immune agents, rendered marked improvements in tumor cures with various cancer models. Another clinically attractive strategy is adoptive immunotherapy, and the prospects of its use in conjunction with PDT are outlined.

Korbelik, Mladen; Sun, Jinghai

1998-05-01

117

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

118

Photodynamic therapy--mechanism and employment.  

PubMed

Photodynamic terapy (PDT) is a new treatment for a wide variety of malignancies and premalignant dysplasias, as well as some non-cancer indications. Therapeutic response to PTD is achieved through the activation of non-toxic photosensitiser located within neoplastic tissue, using visible light tuned to the appropriate absorption band of the photosensitiser molecule. This produces cytotoxic free radical such as singlet oxigen, which result in local photo-oxidation, cell damage and destruction of the tumour cells. Systemic administration of photosensitisers has been used with endoscopic light exposure to treat a variety of internal malignances. A topical drug delivery is used in the skin deseases treatment. The selective distribution of photosensitiser in the target tissue is the fundamental to the process of PDT. This tissue specific photosensitation and normal tissue sparing results in good healing and often very good cosmetic results. Peterson PTD can be used for the treatment of cutaneous lesions (e.g., SCC, BCC, Bowen's disease, mycosis fungoides, erythroplasia of Queyrat, Gorlin's Syndrome, actinic keratoses), lower genital tract neoplasia (VIN and CIN), gastrointestinal tumours, etc., as well as nononcological indications (e.g., acne, condyloma acuminatum, lichen planus, psoriasis, vitiligo, vulval lichen sclerosus, warts and verrucae). PMID:16146137

Szpringer, Ewa; Lutnicki, Krzysztof; Marciniak, Andrzej

2004-01-01

119

An overview of adjuvant therapy for colorectal cancer  

Microsoft Academic Search

Adjuvant therapy of colorectal cancer is one of the most active areas of clinical oncology research. Although the data for the benefits from early trials of adjuvant therapy were inconclusive, these trials suffered from inadequate sample sizes, poor staging, potentially suboptimal treatment regimens and ill-defined prognostic subgroups. More recently, larger trials of higher scientific quality have demonstrated that regimens of

D. G Haller

1995-01-01

120

Development of Low-Cost Photodynamic Therapy Device  

NASA Astrophysics Data System (ADS)

Photodiagnosis and photodynamic therapy of non-melanoma skin cancers using delta-aminolevulinic acid/protoporphyrin IX (5-ALA/PpIX) give a combined application with broadest dissemination in the current clinical practice. The problems with using of lasers as light sources are the expenses associated with the operation of these types of installations. This is why we test the capability of cheaper sources - light-emitting diodes at 405 nm for fluorescence excitation of PpIX and 635 nm for photodynamic action initiation. A LED matrix is developed in our laboratory using two types of LEDs and a combined photodiagnosis/photodynamic theory device applicable for clinical practice is built. Geometrically matrix is formed in such way that power density at 635 nm is about 40 mW/cm2, which allow to reach treatment doses for a 15-20 min irradiation depending of the lesion size in the focus of the system. The therapeutic mode of system developed can be used also with some other photosensitizers from the porphyrins derivatives family.

Momchilov, N.; Bliznakova, I.; Borisova, E.; Troyanova, P.

2007-11-01

121

Accurate dosimetry for monitoring response to photodynamic therapy  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is becoming a treatment of choice for cancer because of its low cost, high effectiveness and low damage to healthy tissue. Successful PDT outcome depends on accurate dosimetry, which is currently lacking, leading to variable and/or ineffective treatment outcome. We report on our research and developmental efforts towards an implicit dosimetric method for PDT that will provide an accurate assessment of treatment effectiveness by continuous monitoring of the in vivo drug concentration and the oxygen concentration in tissue. This approach uses the same tools presently available for PDT, making it attractive to the health professionals without increasing treatment cost.

Seetamraju, M.; Gurjar, R. S.; Myers, R.; Hasan, T.; Wolf, D. E.

2012-02-01

122

Photodynamic therapy treatment for eyes with drusenoid pigment epithelium detachment.  

PubMed

We report the clinical course of photodynamic therapy (PDT) in a patient with drusenoid pigment epithelium detachment (PED). A patient with drusenoid PED underwent PDT follow-up was carried out at one week, one month, three months, six months and one year after treatment. Fundus exam, optical coherence tomography (OCT) and fluorescein angiography were performed. After the PDT, drusen and PED were gradually diminished over one year. However, pure serous PED eventually developed at the same location of the drusenoid PED. The results of the PDT, on drusenoid PED, were initially effective, but not completely successful. Therefore, PDT may be considered as an alternative treatment option for drusenoid PED. PMID:18784450

Lee, Na Young; Kim, Ki Seok

2008-09-01

123

Targeted Laryngeal Photodynamic Therapy with a Balloon Diffusing Light Source  

PubMed Central

Photodynamic therapy (PDT) has been used for premalignant mucosal lesions. In an attempt to treat a patient with recurrent high-grade dysplasia of the glottic larynx, we were faced with technical challenges leading us to abandon the classic microlens fiber for a 2-cm long translucent diffusing balloon catheter to deliver photoactivating light to the targeted lesion. Real-time measurements confirmed stable photobleaching with augmentation of the prescribed light fluence secondary to light scatter in regions not in contact with the balloon diffuser. We report a potential new application of the balloon catheter that may be more suitable for anterior glottic lesions associated with minimal acute toxicity.

Grossman, Craig; Zhu, Timothy; Finlay, Jarod; Dimofte, Andrea; Malloy, Kelly; O'Malley, Bert; Weinstein, Gregory; Busch, Theresa; Quon, Harry

2010-01-01

124

Synthesis, bioanalysis and biodistribution of photosensitizer conjugates for photodynamic therapy  

PubMed Central

Photodynamic therapy (PDT) was discovered in 1900 by Raab, and has since emerged as a promising tool for treating diseases characterized by unwanted cells or hyperproliferating tissue (e.g., cancer or infectious disease). PDT consists of the light excitation of a photosensitizer (PS) in the presence of O2 to yield highly reactive oxygen species. In recent years, PDT has been improved by the synthesis of targeted bioconjugates between monoclonal antibodies and PS, and by investigating PS biodistribution and PD. Here, we provide a comprehensive review of major developments in PS-immunoconjugate-based PDT and the bioanalysis of these agents, with a specific emphasis on anticancer and antimicrobial PDT.

Denis, Tyler GSt; Hamblin, Michael R

2013-01-01

125

Biomodulatory Approaches to Photodynamic Therapy for Solid Tumors  

PubMed Central

Photodynamic Therapy (PDT) uses a photosensitizing drug in combination with visible light to kill cancer cells. PDT has an advantage over surgery or ionizing radiation because PDT can eliminate tumors without causing fibrosis or scarring. Disadvantages include the dual need for drug and light, and a generally lower efficacy for PDT versus surgery. This minireview describes basic principles of PDT, photosensitizers available, and aspects of tumor biology that may provide further opportunities for treatment optimization. An emerging biomodulatory approach, using methotrexate or Vitamin D in combination with aminolevulinate-based PDT, is described. Finally, current clinical uses of PDT for solid malignancies are reviewed.

Anand, Sanjay; Ortel, Bernhard J.; Pereira, Stephen P.; Hasan, Tayyaba; Maytin, Edward V.

2012-01-01

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

Dual imaging-guided photothermal/photodynamic therapy using micelles.  

PubMed

We report a type of photosensitizer (PS)-loaded micelles integrating cyanine dye as potential theranostic micelles for precise anatomical tumor localization via dual photoacoustic (PA)/near-infrared fluorescent (NIRF) imaging modalities, and simultaneously superior cancer therapy via sequential synergistic photothermal therapy (PTT)/photodynamic therapy (PDT). The micelles exhibit enhanced photostability, cell internalization and tumor accumulation. The dual NIRF/PA imaging modalities of the micelles cause the high imaging contrast and spatial resolution of tumors, which provide precise anatomical localization of the tumor and its inner vasculature for guiding PTT/PDT treatments. Moreover, the micelles can generate severe photothermal damage on cancer cells and destabilization of the lysosomes upon PTT photoirradiation, which subsequently facilitate synergistic photodynamic injury via PS under PDT treatment. The sequential treatments of PTT/PDT trigger the enhanced cytoplasmic delivery of PS, which contributes to the synergistic anticancer efficacy of PS. Our strategy provides a dual-modal cancer imaging with high imaging contrast and spatial resolution, and subsequent therapeutic synergy of PTT/PDT for potential multimodal theranostic application. PMID:24613048

Guo, Miao; Mao, Huajian; Li, Yanli; Zhu, Aijun; He, Hui; Yang, Hong; Wang, Yangyun; Tian, Xin; Ge, Cuicui; Peng, Qiaoli; Wang, Xiaoyong; Yang, Xiangliang; Chen, Xiaoyuan; Liu, Gang; Chen, Huabing

2014-05-01

128

Graduation project: Instrumentation System for Photodynamic Therapy  

Microsoft Academic Search

Glioblastoma Multiforme is a very aggressive kind of brain cancer. When it is diagnosed, the tumor will be between the size of a pingpong ball and a tennis ball, as shown in picture 1. It accounts for half the brain cancers. Current treatments consists of radio- and chemo-therapy, but the 5 year survival rate is only 3 % with this

J. Kaptein

2008-01-01

129

Efficient photodynamic therapy on human retinoblastoma cell lines.  

PubMed

Photodynamic therapy (PDT) has shown to be a promising technique to treat various forms of malignant neoplasia. The photodynamic eradication of the tumor cells is achieved by applying a photosensitizer either locally or systemically and following local activation through irradiation of the tumor mass with light of a specific wavelength after a certain time of incubation. Due to preferential accumulation of the photosensitizer in tumor cells, this procedure allows a selective inactivation of the malignant tumor while sparing the surrounding tissue to the greatest extent. These features and requirements make the PDT an attractive therapeutic option for the treatment of retinoblastoma, especially when surgical enucleation is a curative option. This extreme solution is still in use in case of tumours that are resistant to conventional chemotherapy or handled too late due to poor access to medical care in less advanced country. In this study we initially conducted in-vitro investigations of the new cationic water-soluble photo sensitizer tetrahydroporphyrin-tetratosylat (THPTS) regarding its photodynamic effect on human Rb-1 and Y79 retinoblastoma cells. We were able to show, that neither the incubation with THPTS without following illumination, nor the sole illumination showed a considerable effect on the proliferation of the retinoblastoma cells, whereas the incubation with THPTS combined with following illumination led to a maximal cytotoxic effect on the tumor cells. Moreover the phototoxicity was lower in normal primary cells from retinal pigmented epithelium demonstrating a higher phototoxic effect of THPTS in cancer cells than in this normal retinal cell type. The results at hand form an encouraging foundation for further in-vivo studies on the therapeutic potential of this promising photosensitizer for the eyeball and vision preserving as well as potentially curative therapy of retinoblastoma. PMID:24498108

Walther, Jan; Schastak, Stanislas; Dukic-Stefanovic, Sladjana; Wiedemann, Peter; Neuhaus, Jochen; Claudepierre, Thomas

2014-01-01

130

Hilar Cholangiocarcinoma: Photodynamic Therapy and Stenting  

Microsoft Academic Search

Carcinomas of the biliary tree are rare tumors of the gastrointestinal tract with rising inci dence during the last years.\\u000a Endoscopic therapy plays a central role in the preopera-tive and palliative treatment of extrahepatic cholangiocarcinoma (CC).\\u000a In obstructive jaundice, biliary drainage may cause only few complications and relieves symptoms reliably. It can prevent\\u000a further complica tions and is indispensable in

Marcus Wiedmann; Joachim Mössner; Helmut Witzigmann

131

Role of adjuvant therapy in surgically resected colorectal carcinoma  

Microsoft Academic Search

An important advance in cancer treatment has been made in recent years with the finding that adjuvant therapy can significantly improve the survival of patients with colorectal cancer. In patients with resected lymph node-positive colon carcinomas (TNM stage 3), adjuvant 5-fluorouracil and levamisole produced an unequivocal survival advantage that established this combination as the standard of clinical practice. Given that

Frank A. Sinicrope; Steven M. Sugarman

1995-01-01

132

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

133

Hematoporphyrin derivative uptake and photodynamic therapy in pancreatic carcinoma  

SciTech Connect

Little information is currently available concerning the uptake of porphyrins by pancreatic tumors, or the effect of photodynamic therapy (PDT) on pancreatic cancer. In Syrian golden hamsters (n = 33), the organ distribution of /sup 125/I-labeled dihematoporphyrin ether (DHE) was studied in a pancreatic cancer model. In the same animal model the effect of PDT was studied using a gold vapor laser for energy delivery 3 hr after the injection of DHE (n = 7). DHE was 2.4 times more concentrated in the pancreatic tumor than in the nontumorous pancreas at 3 hr. Simultaneously there was a considerable accumulation of DHE in the surrounding gastrointestinal tract, causing perforation of the duodenum and jejunum with resultant death in four (57%) animals after PDT. Photodynamic therapy caused extensive tumor necrosis without any obvious effect on the nontumor-bearing pancreas. Damage to the surrounding tissue in the hamster indicates that precautions should be taken if PDT is to be used clinically in pancreatic cancer. Intratumoral injection of DHE may give higher drug concentrations with greater specificity for tumor treatment.

Schroder, T.; Chen, I.W.; Sperling, M.; Bell, R.H. Jr.; Brackett, K.; Joffe, S.N.

1988-05-01

134

Measurement of Intracellular Oxygen Concentration During Photodynamic Therapy in vitro.  

PubMed

A technique is introduced that monitors the depletion of intracellular ground state oxygen concentration ([(3) O2 ]) during photodynamic therapy of Mat-LyLu cell monolayers and cell suspensions. The photosensitizer Pd(II) meso-tetra(4-carboxyphenyl)porphine (PdT790) is used to manipulate and indicate intracellular [(3) O2 ] in both of the in vitro models. The Stern-Volmer relationship for PdT790 phosphorescence was characterized in suspensions by flowing nitrogen over the suspension while short pulses of 405 nm light were used to excite the sensitizer. The bleaching of sensitizer and the oxygen consumption rate were also measured during continuous exposure of the cell suspension to the 405 nm laser. Photodynamic therapy (PDT) was conducted in both cell suspensions and in cell monolayers under different treatment conditions while the phosphorescence signal was acquired. The intracellular [(3) O2 ] during PDT was calculated by using the measured Stern-Volmer relationship and correcting for sensitizer photobleaching. In addition, the amount of oxygen that was consumed during the treatments was calculated. It was found that even at large oxygen consumption rates, cells remain well oxygenated during PDT of cell suspensions. For monolayer treatments, it was found that intracellular [(3) O2 ] is rapidly depleted over the course of PDT. PMID:24521344

Weston, Mark A; Patterson, Michael S

2014-07-01

135

Vascular Targeted Photodynamic Therapy for Localized Prostate Cancer  

PubMed Central

Survival for men diagnosed with prostate cancer directly depends on the stage and grade of the disease at diagnosis. Prostate cancer screening has greatly increased the ability to diagnose small and low-grade cancers that are amenable to cure. However, widespread prostate-specific antigen screening exposes many men with low-risk cancers to unnecessary complications associated with treatment for localized disease without any survival advantage. One challenge for urological surgeons is to develop effective treatment options for low-risk disease that are associated with fewer complications. Minimally invasive ablative treatments for localized prostate cancer are under development and may represent a preferred option for men with low-risk disease who want to balance the risks and benefits of treatment. Vascular targeted photodynamic therapy (VTP) is a novel technique that is being developed for treating prostate cancer. Recent advances in photodynamic therapy have led to the development of photosynthesizers that are retained by the vascular system, which provides the opportunity to selectively ablate the prostate with minimal collateral damage to other structures. The rapid clearance of these new agents negates the need to avoid exposure to sunlight for long periods. Presented herein are the rationale and preliminary data for VTP for localized prostate cancer.

Lepor, Herbert

2008-01-01

136

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

137

The Role of Photodynamic Therapy for Hilar Cholangiocarcinoma  

PubMed Central

The prognosis for hilar cholangiocarcinoma is limited by tumor spread along the biliary tree leading to refractory obstructive cholestasis, cholangitis, and liver failure. Palliation with biliary endoprostheses results in median survival times of 4-6 months for advanced bile duct cancer. Photodynamic therapy (PDT) is a local photochemical tumor treatment consisting of a photosensitizing agent combined with laser irradiation of a distinct wavelength. Tumor ablation with PDT combined with biliary stenting reduces cholestasis and significantly improves median survival time. However, the treatment is not widely available, and the photosensitizers used for PDT cause prolonged photosensitivity. Optimum control of tumor spread along the bile ducts and control of cholestasis and cholangitis will prolong survival in one to two thirds of patients, and renders them suitable for other antitumor therapies.

2010-01-01

138

Photodynamic Therapy for Gynecological Diseases and Breast Cancer  

PubMed Central

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.

Shishkova, Natashis; Kuznetsova, Olga; Berezov, Temirbolat

2012-01-01

139

A novel antiangiogenic approach for adjuvant therapy of pancreatic carcinoma  

Microsoft Academic Search

Introduction  Surgical therapy remains the only curative option for pancreatic ductal adenocarcinoma. But even after complete resection,\\u000a almost all patients suffer from local tumor recurrence. Current standard adjuvant therapy with gemcitabine does not impressively\\u000a affect the recurrence rate. The aim of this study was to evaluate a novel anti-angiogenic adjuvant treatment strategy by targeting\\u000a the vascular endothelial growth factor receptor (VEGFR).

Peer Joensson; Birgit Hotz; Heinz Johannes Buhr; Hubert G. Hotz

2011-01-01

140

Targeted photodynamic therapy for infected wounds in mice  

NASA Astrophysics Data System (ADS)

Although many workers have used photodynamic therapy to kill bacteria in vitro, the use of this approach has seldom been reported in vivo in animal models of infection. We report on the use of a targeted polycationic photosensitizer conjugate between poly-L-lysine and chlorin(e6) that can penetrate the Gram (-) outer membrane together with red laser light to kill Escherichia coli and Pseudomonas aeruginosa infecting excisional wounds in mice. We used genetically engineered luminescent bacteria that allowed the infection to be imaged in mouse wounds using a sensitive CCD camera. Wounds were infected with 5x106 bacteria, followed by application of the conjugate in solution and illumination. There was a light-dose dependent loss of luminescence as measured by image analysis in the wound treated with conjugate and light, not seen in control wounds. This strain of E coli is non-invasive and the infection in untreated wounds spontaneously resolved in a few days and all wounds healed equally well showing the photodynamic treatment did not damage the host tissue. P aeruginosa is highly invasive and mice with untreated or control wounds all died while 90% of PDT treated mice survived. PDT may have a role to play in the rapid treatment of infected wounds in view of the worldwide rise in antibiotic resistance.

Hamblin, Michael R.; O'Donnell, David A.; Zahra, Touqir; Contag, Christopher H.; McManus, Albert T.; Hasan, Tayyaba

2002-06-01

141

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

142

Evaluation of photodynamic therapy in adhesion protein expression  

PubMed Central

Photodynamic therapy (PDT) is a treatment modality that has clinical applications in both non-neoplastic and neoplastic diseases. PDT involves a light-sensitive compound (photosensitizer), light and molecular oxygen. This procedure may lead to several different cellular responses, including cell death. Alterations in the attachment of cancer cells to the substratum and to each other are important consequences of photodynamic treatment. PDT may lead to changes in the expression of cellular adhesion structure and cytoskeleton integrity, which are key factors in decreasing tumor metastatic potential. HEp-2 cells were photosensitized with aluminum phthalocyanine tetrasulfonate and zinc phthalocyanine, and the proteins ?1-integrin and focal adhesion kinase (FAK) were assayed using fluorescence microscopy. The verification of expression changes in the genes for FAK and ?1 integrin were performed by reverse transcription-polymerase chain reaction (RT-PCR). The results revealed that HEp-2 cells do not express ?-integrin or FAK 12 h following PDT. It was concluded that the PDT reduces the adhesive ability of HEp-2 cells, inhibiting their metastatic potential. The present study aimed to analyze the changes in the expression and organization of cellular adhesion elements and the subsequent metastatic potential of HEp-2 cells following PDT treatment.

PACHECO-SOARES, CRISTINA; MAFTOU-COSTA, MAIRA; DA CUNHA MENEZES COSTA, CAROLINA GENUNCIO; DE SIQUEIRA SILVA, ANDREZA CRISTINA; MORAES, KAREN C.M.

2014-01-01

143

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

144

Cytotoxic efficacy of photodynamic therapy in osteosarcoma cells in vitro.  

PubMed

In recent years, there has been the difficulty in finding more effective therapies against cancer with less systemic side effects. Therefore Photodynamic Therapy is a novel approach for a more tumor selective treatment. Photodynamic Therapy (PDT) that makes use of a nontoxic photosensitizer (PS), which, upon activation with light of a specific wavelength in the presence of oxygen, generates oxygen radicals that elicit a cytotoxic response(1). Despite its approval almost twenty years ago by the FDA, PDT is nowadays only used to treat a limited number of cancer types (skin, bladder) and nononcological diseases (psoriasis, actinic keratosis)(2). The major advantage of the use of PDT is the ability to perform a local treatment, which prevents systemic side effects. Moreover, it allows the treatment of tumors at delicate sites (e.g. around nerves or blood vessels). Here, an intraoperative application of PDT is considered in osteosarcoma (OS), a tumor of the bone, to target primary tumor satellites left behind in tumor surrounding tissue after surgical tumor resection. The treatment aims at decreasing the number of recurrences and at reducing the risk for (postoperative) metastasis. In the present study, we present in vitro PDT procedures to establish the optimal PDT settings for effective treatment of widely used OS cell lines that are used to reproduce the human disease in well established intratibial OS mouse models. The uptake of the PS mTHPC was examined with a spectrophotometer and phototoxicity was provoked with laser light excitation of mTHPC at 652 nm to induce cell death assessed with a WST-1 assay and by the counting of surviving cells. The established techniques enable us to define the optimal PDT settings for future studies in animal models. They are an easy and quick tool for the evaluation of the efficacy of PDT in vitro before an application in vivo. PMID:24686859

Meier, Daniela; Campanile, Carmen; Botter, Sander M; Born, Walter; Fuchs, Bruno

2014-01-01

145

Photodynamic hyperthermal chemotherapy with indocyanine green: a novel cancer therapy for 16 cases of malignant soft tissue sarcoma  

PubMed Central

Sixteen cases of malignant soft tissue sarcoma (STS; 10 canines and six felines) were treated with a novel triple therapy that combined photodynamic therapy, hyperthermia using indocyanine green with a broadband light source, and local chemotherapy after surgical tumor resection. This triple therapy was called photodynamic hyperthermal chemotherapy (PHCT). In all cases, the surgical margin was insufficient. In one feline case, PHCT was performed without surgical resection. PHCT was performed over an interval of 1 to 2 weeks and was repeated three to 21 times. No severe side effects, including severe skin burns, necrosis, or skin suture rupture, were observed in any of the animals. No disease recurrence was observed in seven out of 10 (70.0%) dogs and three out of six (50.0%) cats over the follow-up periods ranging from 238 to 1901 days. These results suggest that PHCT decreases the risk of STS recurrence. PHCT should therefore be considered an adjuvant therapy for treating companion animals with STS in veterinary medicine.

Onoyama, Masaki; Tsuka, Takeshi; Imagawa, Tomohiro; Osaki, Tomohiro; Minami, Saburo; Azuma, Kazuo; Kawashima, Kazuhiko; Ishi, Hiroshi; Takayama, Takahiro; Ogawa, Nobuhiko

2014-01-01

146

A Review of Photodynamic Therapy for Herpes Simplex: Benefits and Potential Risks.  

National Technical Information Service (NTIS)

A recently developed photodynamic therapy for herpes simplex consists of exposing viral lesions to visible light following application of a photosensitizing dye. Animal and human clinical trials show reduction of oral and genital herpes virus infectivity....

L. E. Bockstahler C. D. Lytle K. B. Hellman

1974-01-01

147

Blue laser system for photo-dynamic therapy  

NASA Astrophysics Data System (ADS)

A blue laser system for eye diseases (age related macular degeneration, sub-retinal neo-vascularisation in myopia and presumed ocular histoplasmosis syndrome - POHS) photo-dynamic therapy, based on riboflavin as photosensitive substance, has been developed. A CW diode laser at 445 nm wavelength was coupled through an opto-mechanical system to the viewing path of a bio-microscope. The laser beam power in the irradiated area is adjustable between 1 mW and 40 mW, in a spot of 3-5 mm diameter. The irradiation time can be programmed in the range of 1-19 minutes. Currently, the laser system is under clinic tests.

Dabu, R.; Carstocea, B.; Blanaru, C.; Pacala, O.; Stratan, A.; Ursu, D.; Stegaru, F.

2007-04-01

148

High-power red diode laser system for photodynamic therapy  

NASA Astrophysics Data System (ADS)

The Applied Optronics Corporation's model LM-400 is the first commercially available visible diode laser system which can meet the light source requirements for photodynamic therapy (PDT). PDT is a treatment for cancer which uses the topical illumination by a precise wavelength of light to photochemically activate an otherwise nontoxic drug, resulting in the localized necrosis of cancerous cells. Following a discussion of the light source requirements for PDT, we describe the system design and performance of AOC's self-contained, all solid- state, visible diode laser system. When compared to dye laser systems pumped by secondary lasers, diode laser systems offer significant advantages in terms of cost, simplicity of operation, portability, and negligible installation and maintenance requirements.

Dupuy, Charles G.; Hwang, C. J.; Benenati, David; Simmonds, H. Thomas; Fu, Richard J.; Bull, Douglas

1994-07-01

149

Photodynamic therapy with Photofrin II by bronchial artery infusion  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) utilizing Photofrin II is proving to be an effective modality in the treatment of early stage lung cancer. However, wider clinical application of Photofrin II as a photosensitizer for various cancers is hampered by the potentially serious and prolonged skin photosensitivity. To prevent these side effects and reduce the inpatient period, we recently tried to give reduced doses of Photofrin II by bronchial artery infusion (BAI). Six patients with endoscopically evaluated early stage carcinoma of the lung were given 0.7 mg/kg of Photofrin II by BAI 48 hours before PDT. Complete remission was obtained in all 6 cases, and there was no evidence of skin photosensitivity when exposed to outside light under careful surveillance at one week after PDT.

Okunaka, Tetsuya; Kato, Harubumi; Konaka, Chimori; Kinoshita, Komei; Yamada, Kimito

1993-03-01

150

Photodynamic therapy in the prophylactic management of bladder cancer  

NASA Astrophysics Data System (ADS)

Nine patients were treated with red light whole bladder photodynamic therapy (WBPDT): five had mucosal involvement (Ta) and four submucosal invasion (T1). Patients received slow intravenous injection with 2mg/kg body weight of photofrin 48-72 hours before undergoing global light treatment via a 22-French cystoscope with a 400-micron quartz fiber bulb (isotropic) tip fiber. Three months after PDT, eight of the patients had normal cystoscopy, and negative biopsy and urine cytology. Two patients who had recurrences at six and twelve months were retreated with a higher dose (20 J/cm2). They had no increased morbidity and no evidence of recurrent disease six months later. WBPDT should be considered as an important alternative treatment for patients who have recurrent or refractory superficial bladder cancer.

Nseyo, Unyime O.; Lundahl, Scott L.; Merrill, Daniel C.

1991-06-01

151

Transient increased exudation after photodynamic therapy of intraocular tumors.  

PubMed

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/m(2) body surface area) was delivered at a dose of 50 J/cm(2) and intensity of 600 mW/cm(2) 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. PMID:23580859

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

2013-01-01

152

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

153

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

154

Syntheses of new porphyrin-type photosensitizers for photodynamic therapy  

NASA Astrophysics Data System (ADS)

In the first part of this paper, syntheses of water-soluble photosensitizers for use in photodynamic therapy are described. Vinylporphyrins and vinylchlorins react with N.N- dimethylmethyleneammonium iodide (Eschenmoser's reagent) to give 2- (dimethylaminomethyl)vinyl derivatives which can be readily quaternized with methyl iodide to give highly water-soluble quaternary ammonium salts. Deuteroporphyrin-IX dimethyl ester undergoes direct substitution with dimethylaminomethyl at the nuclear 2- and 4-positions. The second part of this report describes the syntheses of bacteriochlorin analogues of natural chlorophyll derivatives; these are obtained by osmium tetraoxide oxidation of chlorins to give vic-dihydroxybacteriochlorins. Acid catalyzed pinacol-pinacolone rearrangements of a number of vic-dihydroxybacterochlorins to given ketobacteriochlorins are described, and the chemistry of the rearrangement is investigated. Biological studies of all sensitizers described will be reported elsewhere.

Smith, Kevin M.; Pandey, Ravindra K.; Shiau, Fuu-Yau; Smith, Norman W.; Iakovides, Panos; Dougherty, Thomas J.

1992-06-01

155

Electron microscopy study of tumor destruction by photodynamic therapy  

NASA Astrophysics Data System (ADS)

Sections of SCCVII tumor (squamous cell carcinoma) grown in C3H mice treated with Photofrin based photodynamic therapy (PDT) were examined by electron microscopy. The tumors were collected at different times after light treatment, and divided according to light penetration into superficial (treatment light oriented) and deep areas. The results show evidence of the progressive destruction of tumor cells occurring in both areas, with the presence of apparently intact tumor cells in the deep region 6 hours after PDT. These healthy looking tumor cells were often found adjacent to heavily damaged tumor cells, which is indicative of selectivity in their killing within the same microregion of tumor tissue. Many histiocytes and mast cells that appeared engaged in tumoricidal activity were also detected. It is suggested that in addition to lethality coming from progressive hemorrhagic necrosis, host immune cells infiltrating the tumor are elicited by PDT and contribute to the indirect killing effect.

Korbelik, Mladen; Matisic, Jasenka; Krosl, Gorazd

1993-06-01

156

Self-assembled liposomal nanoparticles in photodynamic therapy  

PubMed Central

Photodynamic therapy (PDT) employs the combination of non-toxic photosensitizers (PS) together with harmless visible light of the appropriate wavelength to produce reactive oxygen species that kill unwanted cells. Because many PS are hydrophobic molecules prone to aggregation, numerous drug delivery vehicles have been tested to solubilize these molecules, render them biocompatible and enhance the ease of administration after intravenous injection. The recent rise in nanotechnology has markedly expanded the range of these nanoparticulate delivery vehicles beyond the well-established liposomes and micelles. Self-assembled nanoparticles are formed by judicious choice of monomer building blocks that spontaneously form a well-oriented 3-dimensional structure that incorporates the PS when subjected to the appropriate conditions. This self-assembly process is governed by a subtle interplay of forces on the molecular level. This review will cover the state of the art in the preparation and use of self-assembled liposomal nanoparticles within the context of PDT.

Sadasivam, Magesh; Avci, Pinar; Gupta, Gaurav K.; Lakshmanan, Shanmugamurthy; Chandran, Rakkiyappan; Huang, Ying-Ying; Kumar, Raj; Hamblin, Michael R.

2013-01-01

157

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

158

Photodynamic therapy: Theoretical and experimental approaches to dosimetry  

NASA Astrophysics Data System (ADS)

Singlet oxygen (1O2) is the major cytotoxic species generated during photodynamic therapy (PDT), and 1O 2 reactions with biological targets define the photodynamic dose at the most fundamental level. We have developed a theoretical model for rigorously describing the spatial and temporal dynamics of oxygen (3O 2) consumption and transport and microscopic 1O 2 dose deposition during PDT in vivo. Using experimentally established physiological and photophysical parameters, the mathematical model allows computation of the dynamic variation of hemoglobin-3O 2 saturation within vessels, irreversible photosensitizer degradation due to photobleaching, therapy-induced blood flow decrease and the microscopic distributions of 3O2 and 1O 2 dose deposition under various irradiation conditions. mTHPC, a promising photosensitizer for PDT, is approved in Europe for the palliative treatment of head and neck cancer. Using the theoretical model and informed by intratumor sensitizer concentrations and distributions, we calculated photodynamic dose depositions for mTHPC-PDT. Our results demonstrate that the 1O 2 dose to the tumor volume does not track even qualitatively with long-term tumor responses. Thus, in this evaluation of mTHPC-PDT, any PDT dose metric that is proportional to singlet oxygen creation and/or deposition would fail to predict the tumor response. In situations like this one, other reporters of biological response to therapy would be necessary. In addition to the case study of mTHPC-PDT, we also use the mathematical model to simulate clinical photobleaching data, informed by a possible blood flow reduction during treatment. In a recently completed clinical trial at Roswell Park Cancer Institute, patients with superficial basal cell carcinoma received topical application of 5-aminolevulinic acid (ALA) and were irradiated with 633 nm light at 10-150 mW cm-2 . Protoporphyrin IX (PpIX) photobleaching in the lesion and the adjacent perilesion normal margin was monitored by fluorescence spectroscopy. We successfully simulate the in vivo photobleaching of PpIX in this patient population over a wide range of irradiances using the PDT model. For most cases, the rate of bleaching slows as treatment progresses, leaving a fraction of the PpIX unbleached despite sustained irradiation. To account for this feature, the model predicts that incorporation of ALA-PDT-induced blood flow reduction is necessary. In addition to using the theoretical method to understand the dose deposited by photodynamic therapy, experimentally, we propose a potential dose metric for Pc 4-PDT. Pc 4 is a promising second generation photosensitizer that is now in Phase I clinical trials for the treatment of cutaneous lesions. We have observed a significant irradiation-induced increase in Pc 4 fluorescence in tumor cell monolayers. The amount of the fluorescence increase observed in vitro strongly correlates to the cell death and mitochondrial swelling reported by the clonogenic cell survival assay and light scattering measurements, respectively. Based on those biological responses, we anticipate that irradiation-induced fluorescence enhancement in Pc 4-PDT may be a potential dose metric.

Wang, Ken Kang-Hsin

159

Photodynamic therapy in dermatology: past, present, and future  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is a noninvasive therapeutic method first introduced in the field of dermatology. It is mainly used for the treatment of precancerous and superficial malignant skin tumors. Today PDT finds new applications not only for nononcologic dermatoses but also in the field of other medical specialties such as otorhinolaryngology, ophthalmology, neurology, gastroenterology, and urology. We are witnessing a broadening of the spectrum of skin diseases that are treated by PDT. Since its introduction, PDT protocol has evolved significantly in terms of increasing method efficacy and patient safety. In this era of evidence-based medicine, it is expected that much effort will be put into creating a worldwide accepted consensus on PDT. A review on the current knowledge of PDT is given, and the historical basis of the method's evolution since its introduction in the 1900s is presented. At the end, future challenges of PDT are focused on discussing gaps that exist for research in the field.

Darlenski, Razvigor; Fluhr, Joachim W.

2013-06-01

160

Current evidence and applications of photodynamic therapy in dermatology  

PubMed Central

In photodynamic therapy (PDT) a photosensitizer – a molecule that is activated by light – is administered and exposed to a light source. This leads both to destruction of cells targeted by the particular type of photosensitizer, and immunomodulation. Given the ease with which photosensitizers and light can be delivered to the skin, it should come as no surprise that PDT is an increasingly utilized therapeutic in dermatology. PDT is used commonly to treat precancerous cells, sun-damaged skin, and acne. It has reportedly also been used to treat other conditions including inflammatory disorders and cutaneous infections. This review discusses the principles behind how PDT is used in dermatology, as well as evidence for current applications of PDT.

Wan, Marilyn T; Lin, Jennifer Y

2014-01-01

161

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

162

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

163

Antimicrobial Photodynamic Therapy for Methicillin-Resistant Staphylococcus aureus Infection  

PubMed Central

Nowadays methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common multidrug resistant bacteria both in hospitals and in the community. In the last two decades, there has been growing concern about the increasing resistance to MRSA of the most potent antibiotic glycopeptides. MRSA infection poses a serious problem for physicians and their patients. Photosensitizer-mediated antimicrobial photodynamic therapy (PDT) appears to be a promising and innovative approach for treating multidrug resistant infection. In spite of encouraging reports of the use of antimicrobial PDT to inactivate MRSA in large in vitro studies, there are only few in vivo studies. Therefore, applying PDT in the clinic for MRSA infection is still a long way off.

Fu, Xiu-jun; Fang, Yong; Yao, Min

2013-01-01

164

Computer database for clinical and experimental photodynamic therapy data  

NASA Astrophysics Data System (ADS)

An outstanding problem in clinical photodynamic therapy (PDT) of cancer is the application of experimental and previous case studies to the prediction of doses and treatment regimes. The problem derives partly from the fact that several sets of data are incomplete and are not accessible during the course of the treatment of an individual patient. The objective of the computer database project is to provide an enabling utility to support decision making and also to analyze objectively pharmacokinetic, chemical pathological and clinical data with a view to identifying previously unrecognized correlations. The database has been initially developed using a data set from a number of clinical studies to assess the pharmacokinetic profiles of the PDT agents being used. It can be used to create a PDT treatment advice knowledge based system, relating to useful treatment strategies for PDT, and insights into areas of research in terms of isolating critical parameters of PDT.

Williams, Tim J.

1994-03-01

165

Photodynamic therapy induces an immune response against a bacterial pathogen  

PubMed Central

Photodynamic therapy (PDT) employs the triple combination of photosensitizers, visible light and ambient oxygen. When PDT is used for cancer, it has been observed that both arms of the host immune system (innate and adaptive) are activated. When PDT is used for infectious disease, however, it has been assumed that the direct antimicrobial PDT effect dominates. Murine arthritis caused by methicillin-resistant Staphylococcus aureus in the knee failed to respond to PDT with intravenously injected Photofrin®. PDT with intra-articular Photofrin produced a biphasic dose response that killed bacteria without destroying host neutrophils. Methylene blue was the optimum photosensitizer to kill bacteria while preserving neutrophils. We used bioluminescence imaging to noninvasively monitor murine bacterial arthritis and found that PDT with intra-articular methylene blue was not only effective, but when used before infection, could protect the mice against a subsequent bacterial challenge. The data emphasize the importance of considering the host immune response in PDT for infectious disease.

Huang, Ying-Ying; Tanaka, Masamitsu; Vecchio, Daniela; Garcia-Diaz, Maria; Chang, Julie; Morimoto, Yuji; Hamblin, Michael R

2012-01-01

166

Evaluating Photodynamic Therapy Efficacy Using Laser Induced Breakdown Spectroscopy  

NASA Astrophysics Data System (ADS)

Laser-induced breakdown spectroscopy (LIBS), is an excellent tool for trace elemental analysis, was exploited for a detecting concentrations of calcium and magnesium in malignant tissues before and after PDT. Calcium and magnesium concentrations are known tobe high in malignancy. Tissues were injected with methylene blue photosensitizer with concentrations 0.5%, 1% and 2%. Two different light sources were used with two different energy densities/each light sources. The results showed a decrease in tissue elements content after PDT application for both calcium and magnesium compared to before PDT application as shown in the tissue spectral lines' intensities which has been reflected in. Type of light source showed no effect on tissue elements content which showed slight differences among the different energy densities. It has been shown that LIBS technique can be adopted method to monitor tumor photodynamic therapy applications.

Fekry, O.; El-Batanouny, M. H.; El-Begawy, M. B.; Harith, M. A.

2011-09-01

167

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

168

Generalized granuloma annulare treated with methylaminolevulinate photodynamic therapy.  

PubMed

Granuloma annulare (GA) is a non-infectious granulomatous dermatosis characterized by annular papules and rarely nodules and plaques, arising on the dorsa of the hands, feet, elbows and knees; it is usually chronic and asymptomatic. The aetiology of GA is unknown, although many hypotheses have been postulated. About 10% of patients affected by GA present the generalized subtype, characterized by a later age of onset and a chronic course with a low tendency to spontaneous resolution. The widespread papular eruption develops on the trunk and upper or lower limbs. Generalized GA is very disfiguring because of the extensive dissemination of the lesions. The response to various treatments, namely topical and intralesional corticosteroids, topical tacrolimus, dapsone, isotretinoin, etretinate or hydroxychloroquine, is usually unsatisfactory. We report 3 cases with long-lasting generalized GA responding to methylaminolevulinate photodynamic therapy. PMID:19155615

Piaserico, S; Zattra, E; Linder, D; Peserico, A

2009-01-01

169

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

PubMed Central

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.

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

2012-01-01

170

Photodynamic therapy in the management of potentially malignant and malignant oral disorders  

PubMed Central

Photodynamic therapy (PDT) is a minimally-invasive surgical tool successfully targeting premalignant and malignant disorders in the head and neck, gastrointestinal tract, lungs and skin with greatly reduced morbidity and disfigurement. The technique is simple, can commonly be carried out in outpatient clinics, and is highly acceptable to patients. The role of photodynamic therapy in the management of oral potentially malignant disorders and early oral cancer is being discussed.

2012-01-01

171

System for integrated interstitial photodynamic therapy and dosimetric monitoring  

NASA Astrophysics Data System (ADS)

Photodynamic therapy for the treatment of cancer relies on the presence of light, sensitizer and oxygen. By monitoring these three parameters during the treatment a better understanding and treatment control could possibly be achieved. Here we present data from in vivo treatments of solid skin tumors using an instrument for interstitial photodynamic therapy with integrated dosimetric monitoring. By using intra-tumoral ALA-administration and interstitial light delivery solid tumors are targeted. The same fibers are used for measuring the fluence rate at the treatment wavelength, the sensitizer fluorescence and the local blood oxygen saturation during the treatment. The data presented is based on 10 treatments in 8 patients with thick basal cell carcinomas. The fluence rate measurements at 635 nm indicate a major treatment induced absorption increase, leading to a limited light penetration at the treatment wavelength. This leads to a far from optimal treatment since the absorption increase prevents peripheral tumor regions from being fully treated. An interactive treatment has been implemented assisting the physician in delivering the correct light dose. The absorption increase can be compensated for by either prolonging the treatment time or increasing the output power of each individual treatment fiber. The other parameters of importance, i.e. the sensitizer fluorescence at 705 nm and the local blood oxygen saturation, are monitored in order to get an estimate of the amount of photobleaching and oxygen consumption. Based on the oxygen saturation signal, a fractionized irradiation can be introduced in order to allow for a re-oxygenation of the tissue.

Johansson, Ann; Soto Thompson, Marcelo; Johansson, Thomas; Bendsoe, Niels; Svanberg, Katarina; Svanberg, Sune; Andersson-Engels, Stefan

2005-04-01

172

Using cellular mechanisms to develop effective combinations of photodynamic therapy and targeted therapies.  

PubMed

The bond between the research laboratory and the clinic is especially strong in the field of photomedicine. Much is learned in preclinical animal models, which is translated to the clinic for investigation, and then refinements in theory and technique are explored back in the laboratory. With many cancers becoming resistant to treatment, photodynamic therapy (PDT) offers a mechanistically distinct alternative. Studies have shown that PDT not only mitigates chemoresistance but also synergizes with chemotherapy and molecularly targeted therapies. From the world of biochemistry comes this unique look at 2 approaches to maximize the photodynamic effect through PDT combinations with targeted therapies: 1) using the molecular response after PDT to guide the selection of targeted agents and 2) preconditioning cancer cells to modulate nuclear molecular targets before PDT. PMID:23055209

Hasan, Tayyaba

2012-10-01

173

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

174

Subfoveal choroidal thickness after photodynamic therapy in patients with acute idiopathic central serous chorioretinopathy  

PubMed Central

Background The purpose of this study was to evaluate changes in subfoveal choroidal thickness after photodynamic therapy in patients with acute idiopathic central serous chorioretinopathy (ICSCR). Methods This was a retrospective observational study conducted in 63 participants. The primary outcome measure was subfoveal choroidal thickness at baseline and 3 days, one week, 4 weeks, and 12 weeks after photodynamic therapy. The secondary outcome measure was indocyanine green angiography at baseline and 4 weeks and 12 weeks after photodynamic therapy. Results Four weeks after photodynamic therapy, 20 (64.51%) symptomatic eyes showed hypofluorescence corresponding to the area of photodynamic therapy irradiation at the posterior pole. The mean subfoveal choroidal thickness increased significantly from 422±132 ?m at baseline to 478±163 ?m at day 3 after treatment (P=0.022) and then decreased to 362±113 ?m at week 4 (P<0.001) and 339±135 ?m at week 12 (P<0.001). Conclusion The subfoveal choroid in patients with acute ICSCR is thicker than in the normal population, and in symptomatic eyes is significantly thicker than in fellow eyes. Photodynamic therapy using a one third dose of verteporfin may decrease choroidal vascular hyperpermeability and choroidal thickness in patients with acute ICSCR.

Dang, Yalong; Sun, Xinfeng; Xu, Yongsheng; Mu, Yalin; Zhao, Manli; Zhao, Jing; Zhu, Yu; Zhang, Chun

2014-01-01

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

Potential uses of interferon ?2 as adjuvant therapy in cancer  

Microsoft Academic Search

Background: The purpose of this study was to provide an overview of the potential uses of adjuvant interferon (IFN) therapy for resected solid tumors at high risk for postsurgical relapse.\\u000aMethods: A MEDLINE search (1970–1994) of the English-language literature for original articles, reviews, and abstracts addressing IFN use in the adjuvant setting together with the authors' collective experience formed the

Sanjiv S. Agarwala; John M. Kirkwood

1995-01-01

177

Adjuvant Therapy for Gallbladder Carcinoma: The Mayo Clinic Experience  

Microsoft Academic Search

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

Douglas G. Gold; Robert C. Miller; Michael G. Haddock; Leonard L. Gunderson; Fernando Quevedo; John H. Donohue; Sumita Bhatia; David M. Nagorney

2009-01-01

178

Selective use of adjuvant radiation therapy in resectable colorectal adenocarcinoma  

Microsoft Academic Search

Colorectal cancer recurs within the operative field in 10-20 per cent of patients undergoing potentially curative surgery. In certain subgroups, the recurrence rate is 20-50 per cent. There are some data to suggest either preoperative or postoperative radiation therapy as an adjuvant to potentially curative surgery can reduce the local operative failure rate. However, since radiation therapy has significant side

A. M. Cohen; L. L. Gunderson; C. E. Welch

2009-01-01

179

Antimicrobial photodynamic therapy and photodynamic inactivation, or killing bugs with dyes and light--a symposium-in-print.  

PubMed

In antimicrobial photodynamic therapy, the photosensitizer (PS) in its ground singlet state absorbs light to give the excited singlet state that can transition to the long-lived triplet state. This PS triplet may undergo energy transfer (Type 2) or electron transfer (Type 1) to oxygen to form reactive oxygen species (singlet oxygen and/or hydroxyl radicals) that can kill both Gram-positive and Gram-negative bacteria and fungi. Infections in animal models can also be treated. PMID:22497420

Hamblin, Michael R

2012-01-01

180

Optimization of light sources for prostate photodynamic therapy  

NASA Astrophysics Data System (ADS)

To deliver uniform photodynamic dose to the prostate gland, it is necessary to develop algorithms that optimize the location and strength (emitted power × illumination time) of each light source. Since tissue optical properties may change with time, rapid (almost real-time) optimization is desirable. We use the Cimmino algorithm because it is fast, linear, and always converges reliably. A phase I motexafin lutetium (MLu)-mediated photodynamic therapy (PDT) protocol is on-going at the University of Pennsylvania. The standard plan for the protocol uses equal source strength and equal spaced loading (1-cm). PDT for the prostate is performed with cylindrical diffusing fibers (CDF) of various lengths inserted to longitudinal coverage within the matrix of parallel catheters perpendicular to a base plate. We developed several search procedures to aid the user in choosing the positions, lengths, and intensities of the CDFs. The Cimmino algorithm is used in these procedures to optimize the strengths of the light catheters at each step of the iterative selection process. Maximum and minimum bounds on allowed doses to points in four volumes (prostate, urethra, rectum, and background) constrain the solutions for the strengths of the linear light sources. Uniform optical properties are assumed. To study how different opacities of the prostate would affect optimization, optical kernels of different light penetration were used. Another goal is to see whether the urethra and rectum can be spared, with minimal effect on PTV treatment delivery, by manipulating light illumination times of the sources. Importance weights are chosen beforehand for organ volumes, and normalized. Compared with the standard plan, our algorithm is shown to produce a plan that better spares the urethra and rectum and is very fast. Thus the combined selection of positions, lengths, and strengths of interstitial light sources improves outcome.

Altschuler, Martin D.; Zhu, Timothy C.; Li, Jun; Hahn, Stephen M.

2005-04-01

181

Magnetic resonance image-guided photodynamic therapy of xenograft pancreas tumors with verteporfin  

NASA Astrophysics Data System (ADS)

Pancreatic cancer generally has very poor prognosis, with less than 4% survival at 5 years after diagnosis. This dismal survival rate is in part due to the aggressive nature of the adenocarcinoma, leading to a late-stage at diagnosis and exhibits resistance to most therapies. Photodynamic therapy (PDT) is a model cellular and vascular therapy agent, which uses light activation of the delivered drug to photosensitize the local cellular millieu. We suggest that interstitial verteporfin (benzoporphyrin derivative monoacid ring A) PDT has the potential to be an adjuvant therapy to the commonly used Gemcitabine chemotherapy. In the current study, an orthotopic pancreatic cancer model (Panc-1) has undergone interstitial verteporfin PDT (40 J/cm with verteporfin and 40 J/cm without verteporfin). Prior to PDT, magnetic resonance (MR) imaging was used to determine the location and size of the tumor within the pancreas, allowing accurate placement of the diffusing fiber. The success of therapy was monitored in vivo by assessing the total tumor and vascular perfusion volumes 24 hours pre- and 48 hours post-PDT. Total tumor and vascular perfusion volumes were determined using T2 weighted (T2W) and Gd-DTPA difference T1 weighted (T1W) turbo spin echo (TSE) MR imaging sequences, respectively. The validity of the in vivo imaging for therapeutic response was confirmed by ex vivo fluorescence and histological staining of frozen tissue sections. The ex vivo DiOC7(3) fluorescence analysis correlates well with the information provided from the MR images, indicating that MR imaging will be a successful surrogate marker for interstitial PDT.

Samkoe, Kimberley S.; Chen, Alina; Rizvi, Imran; O'Hara, Julia A.; Hoopes, P. Jack; Hasan, Tayyaba; Pogue, Brian W.

2009-02-01

182

Photodynamic therapy: current evidence and applications in dermatology.  

PubMed

Photodynamic therapy (PDT) involves the activation of a photosensitizing drug, which preferentially localizes to diseased skin, by irradiation with light to cause selective cytotoxic damage. Since its discovery in the early 20th century and the development of topical photosensitizers 2 decades ago, PDT is increasingly being used in dermatology for a wide range of neoplastic, inflammatory, and infectious cutaneous conditions. Topical 5-aminolevulinic acid and methyl aminolevulinic acid, the most commonly used agents in PDT, have received Food and Drug Administration approval for the treatment of actinic keratoses, and many second-generation photosensitizers are under investigation. Compared with conventional therapies, PDT has the advantage of being noninvasive and capable of field treatment. It is also associated with quicker recovery periods and excellent cosmetic results. Because of these benefits, PDT is being evaluated as a potential treatment option for many dermatologic conditions and has been shown to be effective for certain nonmelanoma skin cancers. Although research is still limited, PDT might also have a therapeutic benefit for cutaneous T-cell lymphoma, acne, psoriasis, leishmaniasis, and warts, among others. This article is a review of the clinical applications of PDT in dermatology and summarizes the current evidence in literature describing its efficacy, safety, and cosmetic outcome. PMID:22123417

Lee, Yoojin; Baron, Elma D

2011-12-01

183

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

184

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

185

Photodynamic Therapy for Bowen's Disease of the Vulva Area  

PubMed Central

Bowen's disease is a squamous cell carcinoma in situ and has the potential to progress to a squamous cell carcinoma. The authors treated two female patients (a 39-year-old and a 41-year-old) with Bowen's disease in the vulva area using topical photodynamic therapy (PDT), involving the use of 5-aminolaevulinic acid and a light-emitting diode device. The light was administered at an intensity of 80 mW/cm2 for a dose of 120 J/cm2 biweekly for 6 cycles. The 39-year-old patient showed excellent clinical improvement, but the other patient achieved only a partial response. Even though one patient underwent a total excision 1 year later due to recurrence, both patients were satisfied with the cosmetic outcomes of this therapy and the partial improvement over time. The common side effect of PDT was a stinging sensation. PDT provides a relatively effective and useful alternative treatment for Bowen's disease in the vulva area.

Kang, Hong-Kyu; Yun, Jeong-Hwan; Son, Young-Min; Roh, Joo-Young

2014-01-01

186

Photodynamic therapy for pancreatic and biliary tract carcinoma  

NASA Astrophysics Data System (ADS)

Patients with non-resectable pancreatic and biliary tract cancer (cholangiocarcinoma and gallbladder cancer) have a dismal outlook with conventional palliative therapies, with a median survival of 3-9 months and a 5 year survival of less than 3%. Surgery is the only curative treatment but is appropriate in less than 20% of cases, and even then is associated with a 5-year survival of less than 30%. Although most applications of photodynamic therapy (PDT) in gastroenterology have been on lesions of the luminal gut, there is increasing experimental and clinical evidence for its efficacy in cancers of the pancreas and biliary tract. Our group has carried out the only clinical study of PDT in pancreatic carcinoma reported to date, and showed that PDT is feasible for local debulking of pancreatic cancer. PDT has also been used with palliative intent in patients with unresectable cholangiocarcinoma, with patients treated with stenting plus PDT reporting improvements in cholestasis, quality of life and survival compared with historical or randomized controls treated with stenting alone. Further controlled studies are needed to establish the influence of PDT and chemotherapy on the survival and quality of life of patients with pancreatic and biliary tract carcinoma.

Pereira, Stephen P.

2009-02-01

187

Stimulation of anti-tumor immunity by photodynamic therapy  

PubMed Central

Photodynamic therapy (PDT) is a rapidly developing cancer treatment that utilizes the combination of nontoxic dyes and harmless visible light to destroy tumors by generating reactive oxygen species. PDT produces tumor-cell destruction in the context of acute inflammation that acts as a ‘danger signal’ to the innate immune system. Activation of the innate immune system increases the priming of tumor-specific T lymphocytes that have the ability to recognize and destroy distant tumor cells and, in addition, lead to the development of an immune memory that can combat recurrence of the cancer at a later point in time. PDT may be also successfully combined with immunomodulating strategies that are capable of overcoming or bypassing the escape mechanisms employed by the progressing tumor to evade immune attack. This article will cover the role of the immune response in PDT anti-tumor effectiveness. It will highlight the milestones in the development of PDT-mediated anti-tumor immunity and emphasize the combination strategies that may improve this therapy.

Mroz, Pawel; Hashmi, Javad T; Huang, Ying-Ying; Lange, Norbert; Hamblin, Michael R

2011-01-01

188

Photodynamic Therapy for Bowen's Disease of the Vulva Area.  

PubMed

Bowen's disease is a squamous cell carcinoma in situ and has the potential to progress to a squamous cell carcinoma. The authors treated two female patients (a 39-year-old and a 41-year-old) with Bowen's disease in the vulva area using topical photodynamic therapy (PDT), involving the use of 5-aminolaevulinic acid and a light-emitting diode device. The light was administered at an intensity of 80 mW/cm(2) for a dose of 120 J/cm(2) biweekly for 6 cycles. The 39-year-old patient showed excellent clinical improvement, but the other patient achieved only a partial response. Even though one patient underwent a total excision 1 year later due to recurrence, both patients were satisfied with the cosmetic outcomes of this therapy and the partial improvement over time. The common side effect of PDT was a stinging sensation. PDT provides a relatively effective and useful alternative treatment for Bowen's disease in the vulva area. PMID:24882981

Kang, Hong-Kyu; Yun, Jeong-Hwan; Son, Young-Min; Roh, Joo-Young; Lee, Jong-Rok

2014-04-01

189

Physical and mathematical modeling of antimicrobial photodynamic therapy.  

PubMed

ABSTRACT. Antimicrobial photodynamic therapy (aPDT) is a promising method to treat local bacterial infections. The therapy is painless and does not cause bacterial resistances. However, there are gaps in understanding the dynamics of the processes, especially in periodontal treatment. This work describes the advances in fundamental physical and mathematical modeling of aPDT used for interpretation of experimental evidence. The result is a two-dimensional model of aPDT in a dental pocket phantom model. In this model, the propagation of laser light and the kinetics of the chemical reactions are described as coupled processes. The laser light induces the chemical processes depending on its intensity. As a consequence of the chemical processes, the local optical properties and distribution of laser light change as well as the reaction rates. The mathematical description of these coupled processes will help to develop treatment protocols and is the first step toward an inline feedback system for aPDT users. PMID:24849516

Bürgermeister, Lisa; López, Fernando Romero; Schulz, Wolfgang

2014-07-01

190

Immunomodulators as adjuvants for vaccines and antimicrobial therapy.  

PubMed

A highly effective strategy for combating infectious diseases is to enhance host defenses using immunomodulators, either preventatively, through vaccination, or therapeutically. The effectiveness of many vaccines currently in use is due in part to adjuvants, molecules that have little immunogenicity by themselves but which help enhance and appropriately skew the immune response to an antigen. The development of new vaccines necessitates the development of new types of adjuvants to ensure an appropriate immune response. Herein, we review commonly used vaccine adjuvants and discuss promising adjuvant candidates. We also discuss various other immunomodulators (namely cytokines, Toll-like receptor agonists, and host defense peptides) that are, or have potential to be, useful for antimicrobial therapies that exert their effects by boosting host immune responses rather than targeting pathogens directly. PMID:20946578

Nicholls, Erin F; Madera, Laurence; Hancock, Robert E W

2010-12-01

191

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

192

Choline PET for Monitoring Early Tumor Response to Photodynamic Therapy  

PubMed Central

Photodynamic therapy (PDT) is a relatively new therapy that has shown promise for treating various cancers in both preclinical and clinical studies. The present study evaluated the potential use of PET with radiolabeled choline to monitor early tumor response to PDT in animal models. Methods Two human prostate cancer models (PC-3 and CWR22) were studied in athymic nude mice. A second-generation photosensitizer, phthalocyanine 4 (Pc 4), was delivered to each animal by a tail vein injection 48 h before laser illumination. Small-animal PET images with 11C-choline were acquired before PDT and at 1, 24, and 48 h after PDT. Time–activity curves of 11C-choline uptake were analyzed before and after PDT. The percentage of the injected dose per gram of tissue was quantified for both treated and control tumors at each time point. In addition, Pc 4-PDT was performed in cell cultures. Cell viability and 11C-choline uptake in PDT-treated and control cells were measured. Results For treated tumors, normalized 11C-choline uptake decreased significantly 24 and 48 h after PDT, compared with the same tumors before PDT (P < 0.001). For the control tumors, normalized 11C-choline uptake increased significantly. For mice with CWR22 tumors, the prostate-specific antigen level decreased 24 and 48 h after PDT. Pc 4-PDT in cell culture showed that the treated tumor cells, compared with the control cells, had less than 50% 11C-choline activity at 5, 30, and 45 min after PDT, whereas the cell viability test showed that the treated cells were viable longer than 7 h after PDT. Conclusion PET with 11C-choline is sensitive for detecting early changes associated with Pc 4-PDT in mouse models of human prostate cancer. Choline PET has the potential to determine whether a PDT-treated tumor responds to treatment within 48 h after therapy.

Fei, Baowei; Wang, Hesheng; Wu, Chunying; Chiu, Song-mao

2010-01-01

193

5-aminolevulinic acid (ALA) mediated photodynamic therapy of bladder cancer cell lines  

NASA Astrophysics Data System (ADS)

Topical application of 5-aminolevulinic acid (ALA) can be effectively used for photodynamic therapy and diagnosis of superficial bladder cancer. Administration of the heme precursor ALA leads to the selective accumulation of the photosensitizer protoporphyrin IX (PPIX) in certain types of tissue. The aim of this study was to determine the cellular PPIX concentration and the effect of photodynamic therapy mediated by ALA on two bladder cancer cell lines (RT4, J82) and a fibroblast cell line (N1). Following incubation with ALA the kinetics of cellular PPIX were examined using flow cytometry combined with extraction. The cancer cell lines showed considerably higher PPIX concentrations than the fibroblast cell line: RT4 1030, J82 710, and N1 110 ng PPIX/mg protein. Photodynamic therapy was performed with an incoherent light source (580 - 740 nm, 40 mW/cm2, 30 J/cm2). In contrast to the fibroblast cell line, which was resistant to photodynamic therapy, the cancer cell lines were effectively killed following the treatment as determined by MTT assay. This study suggests that ALA-mediated photodynamic therapy may be effective in transitional cell carcinoma of the bladder. Based on these findings, this therapeutic method should be further evaluated clinically.

Fickweiler, Sonja; Krieg, Rene; Stepp, Herbert G.; Hofstaedter, Ferdinand; Knuechel, Ruth

1999-02-01

194

Photodynamic Therapy with Hypericin Improved by Targeting HSP90 Associated Proteins  

PubMed Central

In this study we have focused on the response of SKBR-3 cells to both single 17-DMAG treatment as well as its combination with photodynamic therapy with hypericin. Low concentrations of 17-DMAG without any effect on survival of SKBR-3 cells significantly reduced metabolic activity, viability and cell number when combined with photodynamic therapy with hypericin. Moreover, IC10 concentation of 17-DMAG resulted in significant increase of SKBR-3 cells in G1 phase of the cell cycle, followed by an increase of cells in G2 phase when combined with photodynamic therapy. Furthermore, 17-DMAG already decreased HER2, Akt, P-Erk1/2 and survivin protein levels in SKBR-3 cells a short time after its application. In this regard, 17-DMAG protected also SKBR-3 cells against both P-Erk1/2 as well as survivin upregulations induced by photodynamic therapy with hypericin. Interestingly, IC10 concentration of 17-DMAG led to total depletion of Akt, P-Erk1/2 proteins and to decrease of survivin level at 48 h. On the other hand, 17-DMAG did not change HER2 relative expression in SKBR-3 cells, but caused a significant decrease of HER2 mRNA in MCF-7 cells characterized by low HER2 expression. These results show that targeting HSP90 client proteins increases the efficiency of antineoplastic effect of photodynamic therapy in vitro.

Solar, Peter; Chytilova, Maria; Solarova, Zuzana; Mojzis, Jan; Ferenc, Peter; Fedorocko, Peter

2011-01-01

195

Oral proliferative verrucous leukoplakia treated with the photodynamic therapy: a case report  

PubMed Central

Summary Aims About 60% of the oral cancer arise on a pre-existent potentially malignant disorder of oral mucosa like the oral proliferative verrucous leukoplakia. The treatment with the photodynamic therapy of these lesions represents, in the last years, an innovative, non-invasive and effective therapeutic possibility to achieve the secondary prevention of oral cancer. In the last decade, case reports have described patients with similar treated through a photochemical reaction induced by laser light. The aim of this study is to evaluate the effectiveness of the topical 5-ALA photodynamic therapy in the treatment of a case of Oral proliferative verrucous leukoplakia. Case report A female patient of 80 years old affected by white verrucous plaques on the right buccal mucosa was recruited for our case report. The right side lesion was treated with the photodynamic therapy with topical administered 5-aminolevulinic acid using the 635 nm laser light to activate the photosensitizer. Results The lesion showed complete response after 4 sessions of photodynamic therapy and no recurrence was noticed after 12 months. Conclusions The photodynamic therapy can be considered an effective treatment in the management of oral verrucous proliferative leukoplakia, but more clinical trials, with prolonged follow-up controls, are necessary to evaluate its effectiveness in the mid and long time period.

Romeo, Umberto; Russo, Nicola; Palaia, Gaspare; Tenore, Gianluca; Del Vecchio, Alessandro

2014-01-01

196

Laser treatment of skin cancer: dissection, photodestruction, and photodynamic therapy  

NASA Astrophysics Data System (ADS)

The analysis of the results of three laser methods of skin cancer treatment in 1535 patients has been made. In 112 patients laser dissection (LD), in 1341 patients laser photodestruction (LPD) and in 82 patients photodynamic therapy (PDT) was performed. LPD was performed in patients with tumors 1.0 to 1.5 cm and with superficial tumors of body and extremities up to 5.0 cm diameter. LAser wounds healed under the crust. Tumor recurrence in 2.5 to 8 months was found out in 22 patients. LD was performed in patients with primary skin tumors 1.0 to 5.0 cm in diameter. The laser wound was sutured or enclosed with the transported skin flap. Tumor recurrence was found out in 3 patients. PDT was performed in patients with multiple, large, recurrent, residual tumors and in cases of 'inconvenient' localizations of tumors on the face. The treatment had effect in 100 percent of tumors. Our experience in use of different laser techniques for skin cancer treatment shows that each of these methods has its own indications and application areas. They are not competitive with each other. These techniques widen the abilities of modern oncology in skin cancer treatment.

Stranadko, Eugeny P.; Skobelkin, Oleg K.; Makeev, Yuri M.; Markichev, Nikolai A.; Riabov, Michail V.; Armitchev, Anatoli V.; Muraviov, Mikhail V.

1996-09-01

197

On the combination of photodynamic therapy with ionizing radiation.  

PubMed

Ehrlich ascites carcinoma growth and cell damage have been examined after photodynamic therapy (PDT), radiotherapy (RT) and combined treatment. Haematoporphyrin dimethyl ether (HPde) is used as a photosensitizer for PDT and tested as a radiosensitizer for RT. For PDT a non-coherent light source (370 < lambda < 680 nm) equipped with filters is used. gamma-Irradiation consists of 60Co irradiation at a dose of 2 Gy. Both PDT and RT induce a significant delay and inhibition in tumour growth (33 and 38%, respectively). Nevertheless cell damage after these treatments is different: after PDT the cell membrane integrity is damaged and no serious chromosomal aberrations are observed; whereas after gamma-irradiation there is no cell membrane integrity damage, but more significant DNA injuries are observed. It seems evident that HPde is able to act as a photosensitizer as well as a radiosensitizer. Combining PDT and RT produces an additive effect, not dependent on the sequence in which the two treatments are given, when a 1 h time window is used. PMID:10643073

Luksiene, Z; Kalvelyte, A; Supino, R

1999-01-01

198

Photodynamic therapy for choroidal neovascularization in young adult patients.  

PubMed

We report our experience with photodynamic therapy (PDT) in the treatment of choroidal neovascularization (CNV) in young adult patients. This was a retrospective study of young adults with CNV treated with PDT. Data collected included age, diagnosis, type and size of CNV, number of treatments, visual outcome, and side effects. Ten patients (11 eyes) were included in the study (mean age 27.2 +/- 13.3 years). Etiologies included multifocal choroiditis (3 eyes), idiopathic CNV (5 eyes), central serous chorioretinopathy (1 eye), and toxoplasma (2 eye). The mean number of treatments was 2 +/- 0.7 and the mean follow-up time was 13.1 +/- 9.5 months. Initial visual acuity (VA) ranged from 20/25 to 20/1,200 (mean logMAR 0.6 +/- 0.5), and improved to 20/20 to 20/250 (mean logMAR 0.46 +/- 0.4) (P = 0.51). Of the four eyes that received additional treatment with oral steroids, one of which also received intravitreal bevacizumab (Avastin) injections, all had visual acuity improvement of 2 or more lines, while only two of seven eyes that received PDT alone showed such improvement. PDT can improve visual outcome in a subgroup of young patients with subfoveal CNV especially when supplemented with oral steroid and bevacizumab injections. PMID:20127140

Ehrlich, Rita; Kramer, Michal; Rosenblatt, Irit; Weinberger, Dov; Mimouni, Karin; Priel, Ethan; Axer-Siegel, Ruth

2010-08-01

199

Subretinal Hemorrhage after Photodynamic Therapy for Juxtapapillary Retinal Capillary Hemangioma  

PubMed Central

A 75-year-old Japanese woman presented with a juxtapapillary retinal capillary hemangioma (RCH) in her left eye. Twelve months after the initial examination, the size of the hemangioma had increased and the exudation from the RCH involved the macula. Her best-corrected visual acuity (BCVA) had decreased from 0.8 to 0.3. A total of five intravitreal injections of bevacizumab (IVB; 1.25 mg) was given but the RCH did not respond. A photodynamic therapy (PDT) was done using multiple laser spots to avoid damaging the optic nerve head. After the first PDT, the subfoveal fluid was reduced but not completely gone. One week after the second PDT, a massive subretinal hemorrhage developed. The subretinal hemorrhage was successfully displaced by injecting intraocular sulfur hexafluoride (SF6) gas. At the 3-year follow-up examination, no subretinal hemorrhage or fluid was observed at the macula and the BCVA remained at 0.05. Our case was resistant to the combination of anti-vascular endothelial growth factor (VEGF) and PDT and had a rare massive subretinal hemorrhage. A further collection of RCH cases treated with anti-VEGF and PDT that would justify this treatment is necessary.

Baba, Takayuki; Kitahashi, Masayasu; Kubota-Taniai, Mariko; Oshitari, Toshiyuki; Yamamoto, Shuichi

2011-01-01

200

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

201

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

202

Photodynamic therapy for locally advanced pancreatic cancer: early clinical results  

NASA Astrophysics Data System (ADS)

Pancreatic adenocarcinoma ranks as the fourth most common cause of cancer death in the USA. Patients usually present late with advanced disease, limiting attempted curative surgery to 10% of cases. Overall prognosis is poor with one-year survival rates of less than 10% with palliative chemotherapy and/or radiotherapy. Given these dismal results, a minimally invasive treatment capable of local destruction of tumor tissue with low morbidity may have a place in the treatment of this disease. In this paper we review the preclinical photodynamic therapy (PDT) studies which have shown that it is possible to achieve a zone of necrosis in normal pancreas and implanted tumour tissue. Side effects of treatment and evidence of a potential survival advantage are discussed. We describe the only published clinical study of pancreatic interstitial PDT, which was carried out by our group (Bown et al Gut 2002), in 16 patients with unresectable locally advanced pancreatic adenocarcinoma. All patients had evidence of tumor necrosis on follow-up imaging, with a median survival from diagnosis of 12.5 months. Finally, we outline a phase I dose-escalation study of verteporfin single fibre PDT followed by standard gemcitabine chemotherapy which our group is currently undertaking in patients with locally advanced pancreatic cancer. Randomized controlled studies are also planned.

Sandanayake, N. S.; Huggett, M. T.; Bown, S. G.; Pogue, B. W.; Hasan, T.; Pereira, S. P.

2010-02-01

203

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

204

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

205

Mycoplasma Removal from Cell Culture Using Antimicrobial Photodynamic Therapy  

PubMed Central

Abstract Objective: The objective of this research was to determine the effectiveness of antimicrobial photodynamic therapy (aPDT) in the removal of mycoplasmas from contaminated cells. Background data: Mycoplasmas often contaminate cell cultures. The cell-contaminating mycoplasmas are removed by antibiotics, but the use of antibiotics usually induces antibiotic-resistant bacteria. aPDT is expected to be a possible alternative to antibiotic treatments for suppressing infections. Materials and Methods: Mycoplasma salivarium (Ms)-infected human embryonic kidney (HEK) 293 cells were irradiated using a red light-emitting diode (LED) in the presence of methylene blue (MB) as a photosensitizer. The Ms viable count was determined using culture on agar plates or using a mycoplasma detection kit. Results: aPDT performed using red LED irradiation was effective in decreasing live Ms in the presence of MB without damaging the HEK293 cells. aPDT removed live Ms from the infected cells after washing the cells with sterilized phosphate-buffered saline (PBS) to decrease the initial number of live Ms before aPDT. Conclusions: This study suggests that aPDT could remove mycoplasmas from contaminated cells.

Hasebe, Akira; Ishikawa, Isao; Shamsul, Haque M.; Ohtani, Makoto; Segawa, Taku; Saeki, Ayumi; Tanizume, Naoho; Oouchi, Manabu; Okagami, Yoshihide; Okano, Teruo

2013-01-01

206

Explicit dosimetry for photodynamic therapy: macroscopic singlet oxygen modeling  

PubMed Central

Singlet oxygen (1O2) is the major cytotoxic agent responsible for cell killing for type-II photodynamic therapy (PDT). An empirical four-parameter macroscopic model is proposed to calculate the “apparent reacted 1O2 concentration”, [1O2]rx, as a clinical PDT dosimetry quantity. This model incorporates light diffusion equation and a set of PDT kinetics equations, which can be applied in any clinical treatment geometry. We demonstrate that by introducing a fitting quantity “apparent singlet oxygen threshold concentration” [1O2]rx,sd, it is feasible to determine the model parameters by fitting the computed [1O2]rx to the Photofrin-mediated PDT-induced necrotic distance using interstitially-measured Photofrin concentration and optical properties within each mouse. After determining the model parameters and the [1O2]rx,sd, we expect to use this model as an explicit dosimetry to assess PDT treatment outcome for a specific photosensitizer in an in vivo environment. The results also provide evidence that the [1O2]rx, because it takes into account the oxygen consumption (or light fluence rate) effect, can be a better predictor of PDT outcome than the PDT dose defined as the energy absorbed by the photosensitizer, which is proportional to the product of photosensitizer concentration and light fluence.

Wang, Ken Kang-Hsin; Finlay, Jarod C.; Busch, Theresa M.; Hahn, Stephen M.; Zhu, Timothy C.

2011-01-01

207

Photodynamic therapy and fluorescent diagnostics of breast cancer  

NASA Astrophysics Data System (ADS)

Photodynamic Therapy (PDT) and fluorescent diagnostics (FD) using Photosense have been provided in 26 patients with breast cancer (BC) and in 108 patients with skin metastases of BC. In 22 patients with T1-T2N0M0 primary tumor PDT was preoperative treatment, with radical mastectomy 7-10 days after PDT. 4 patients had residual tumor after radiotherapy. FD was fulfilled with spectranalyser. We used semiconductive laser for PDT-?=672+2nm, P=1,5 W, interstitial irradiation 2-24 hours after PS injection in light dose 150-200 J/cm3 in patients with primary tumor and multiple surface irradiations (1-4) with interval 24-48 hours and total light dose 400-600 J/cm2 for metastases. Partial regression of tumor with pathomorphosis of 2-4 degree has been found in 23 cases in first group. Treating metastases we had overall response rate of 86,9% with complete response (CR) in 51,5% and partial response in 35,4%. In a year after PDT in 52 patients with CR we had CR in 36,6%, local recurrences in 23,1%, progression (distant [lung or bone] metastasis) in 40,4% of cases. Our experience show pronounced efficacy of FD for detecting tumor borders and PDT for treating BC as preoperative modality and as palliation in cases of recurrencies.

Vakulovskaya, Elena G.; Letyagin, Victor P.; Umnova, Loubov V.; Vorozhcsov, Georgiu N.; Philinov, Victor

2004-06-01

208

Photodynamic therapy mediated induction of early response genes.  

PubMed

Photodynamic therapy (PDT) generates reactive oxygen species which initiate the cytotoxic events of this tumor treatment. We demonstrate that PDT mediated oxidative stress induced a transient increase in the early response genes c-fos, c-jun, c-myc, and egr-1 in murine radiation-induced fibrosarcoma cells. Incubation of exponentially growing cells with porphyrin based photosensitizers in the dark also induced an increase in mRNA levels of early response genes. However, the xanthine photosensitizer, rose bengal, produced increased c-fos mRNA levels only following light treatment. Nuclear runoff experiments confirmed that the induction of c-fos mRNA is controlled in part at the level of transcription. Likewise, a chloramphenicol acetyltransferase reporter construct containing the major c-fos transcriptional response elements was inducible by porphyrin and PDT. Signal transduction pathways associated with PDT mediated c-fos activation were examined by treating cells with protein kinase inhibitors. Staurosporine and 1-(5-isoquinolinesulfonyl)-2-methylpiperazine inhibited PDT mediated c-fos activation while N-(2-guanidinoethyl)-5-isoquinoline-sulfonamide had no effect. In addition, quinacrine, which can inhibit phospholipase activity, blocked PDT induced c-fos mRNA expression. These results suggest that photosensitizer mediated oxidative stress acts through protein kinase-mediated signal transduction pathway(s) to activate early response genes. PMID:8118827

Luna, M C; Wong, S; Gomer, C J

1994-03-01

209

Model for monitoring the process of photodynamic therapy in patients  

NASA Astrophysics Data System (ADS)

The photodynamic therapy (PDT) on tumors is quite effective and widely applied but usually carried out without an immediate evaluation of results. We measured the tumor fluorescence in mice with a fiber probe connected to a linear array spectral analyzer (PMA-11, Hamamatsu Photonics). The spectrum showed a transient change in fluorescence color from red to green during Photofrin?R-mediated PDT. In order to examine the source of green fluorescence, the mitochondria were accessed under a Nipkow disk-scanning confocal microscope in the HeLa cell in culture after labeling them with a red fluorescent protein (DsRed1-mito) and staining the cell with Photofrin?R (Axcan Scandipharm). Changes in fluorescence color from red to green were observed in the area of mitochondria upon their swelling during irradiation. This finding in vitro provided clear evidence that the change in fluorescence color from red to green observed in vivo was due to the mitochondrial destruction associated with the cell-death by PDT. This technique of spectral monitoring in tumor may be useful for detection of the cell-death signal during PDT in patients.

Yoshida, Takato O.; Kohno, Eiji; Sakurai, Takashi; Hirano, Toru; Yamamoto, Seiji; Terakawa, Susumu

2005-07-01

210

Photodynamic therapy of dysplasia in Barrett's esophagus: an update  

NASA Astrophysics Data System (ADS)

Photodynamic therapy using Photofrin has been used as an alternative to esophagectomy for patients with dysplasia or superficial cancer associated with Barrett's esophagus. In this update we present the results in 71 patients treated and followed for 6-72 months. 54 patients had high grade dysplasia/early cancer, and 17 had low grade dysplasia. 22 Patients had early cancer and 1 had T2 cancer. Three separate PDT treatments were required in 3 patients, 2 in 20 patients and 1 in 48. All patients were maintained on omeprazole. Patients received a photofrin dose of 2 mg/kg followed two days later by 630 nm laser light from an either argon/dye laser or KTP/dye laser. The majority of patients received light from a balloon light delivery device. Dysplasia and carcinoma was eliminated or reduced in majority of the cases. 75-80 percent of Barrett's mucosa was replaced by squamous epithelium. 34 patients developed strictures. All responded well to dilation.

Panjehpour, Masoud; Overholt, Bergein F.

1997-05-01

211

Cell death mechanisms vary with photodynamic therapy dose and photosensitizer  

NASA Astrophysics Data System (ADS)

Mouse lymphoma L5178Y-R cells respond to photodynamic therapy (PDT) by undergoing rapid apoptosis, which is induced by PDT-activated signal transduction initiating in the damaged cellular membranes. To relate the level of PDT damage and photosensitizer to the mechanism of cell death, apoptosis has been detected by agarose gel electrophoresis of fragmented DNA and quantified by flow cytometry of cells after staining with Hoechst33342 and propidium iodide, a technique which can distinguish between live, apoptotic, and necrotic cells. When the silicon phthalocyanine Pc 4 or Pc 12 served as photosensitizer, lethal doses (as defined by clonogenic assay) of PDT induced apoptosis in essentially all cells, whereas supralethal doses prevented the characteristic degradation of DNA into oligonucleosomal fragments. In contrast with aluminum phthalocyanine (AlPc) cells died by apoptosis after all doses studied. It appears that high PDT doses with Pc 4 or Pc 12 damage enzymes needed to carry out the program of apoptosis; the absence of this effect with AlPc suggests either a different intracellular location or different photocytotoxic mechanism for the two photosensitizers.

He, Jin; Oleinick, Nancy L.

1994-10-01

212

Cell death mechanisms vary with photodynamic therapy dose and photosensitizer  

NASA Astrophysics Data System (ADS)

Mouse lymphoma L5178Y-R cells respond to photodynamic therapy (PDT) by undergoing rapid apoptosis, which is induced by PDT-activated signal transduction initiating in the damaged cellular membranes. To relate the level of PDT damage and photosensitizer to the mechanism of cell death, apoptosis has been detected by agarose gel electrophoresis of fragmented DNA and quantified by flow cytometry of cells after staining with Hoechst33342 and propidium iodide, a technique which can distinguish between live, apoptotic, and necrotic cells. When the silicon phthalocyanine Pc 4 or Pc 12 served as photosensitizer, lethal doses (as defined by clonogenic assay) of PDT induced apoptosis in essentially all cells, whereas supralethal doses prevented the characteristic degradation of DNA into oligonucleosomal fragments. In contrast with aluminum phthalocyanine (AlPc) cells died by apoptosis after all doses studied. It appears that high PDT doses with Pc 4 or Pc 12 damage enzymes needed to carry out the program of apoptosis; the absence of this effect with AlPc suggests either a different intracellular location or different photocytotoxic mechanism for the two photosensitizers.

He, Jin; Oleinick, Nancy L.

1995-03-01

213

Photodynamic therapy for melanoma: efficacy and immunologic effects  

NASA Astrophysics Data System (ADS)

Malignant melanoma is one of the fastest growing cancers and if it cannot be completely surgically removed the prognosis is bleak. Melanomas are known to be particularly resistant to both chemotherapy and radiotherapy. Various types of immunotherapy have however been investigated with mixed reports of success. Photodynamic therapy (PDT) has also been tested against melanoma, again with mixed effects as the melanin pigment is thought to act as both an optical shield and as an antioxidant. We have been investigating PDT against malignant melanoma in mouse models. We have compared B16F10 melanoma syngenic to C57BL/6 mice and S91 Cloudman melanoma syngenic to DBA2 mice. We have tested the hypothesis that S91 will respond better than B16 because of higher expression of immunocritical molecules such as MHC-1, tyrosinase, tyrosinase related protein-2 gp100, and intercellular adhesion molecule-1. Some of these molecules can act as tumor rejection antigens that can be recognized by antigen-specific cytotoxic CD8 T cells that have been stimulated by PDT. Moreover it is possible that DBA2 mice are intrinsically better able to mount an anti-tumor immune response than C57BL/6 mice. We are also studying intratumoral injection of photosensitzers such as benzoporphyrin monoacid ring A and comparing this route with the more usual route of intravenous administration.

Avci, Pinar; Gupta, Gaurav K.; Kawakubo, Masayoshi; Hamblin, Michael R.

2014-02-01

214

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

215

Viability for the conjugate use of electrosurgery and photodynamic therapy  

NASA Astrophysics Data System (ADS)

Photodynamic Therapy (PDT) is a technique for destroying tumor cells with little harm to surrounding healthy tissue. However, the light wavelength has limited penetration in the tissue, making the association of a surgical procedure needed for larger lesions. Electrosurgery (ES) is a recommended excision technique, but the optical properties of the tissue damaged by ES and its influence on PDT procedure are unknown. Twelve rats (Wistar) composed the animal model of four groups (ES, PDT, ES+PS+Light, PS+ES+Light), evaluating different orders of conjugation via fluorescence, imaging and necrosis depth. First histopathological analysis has shown a highly modified surface of tissue (integral structure loss and dehydration shrinkage), protein denaturation, accompanied by bleeding and inflammatory damage. Fluorescence imaging showed strong scattering of light at the surface of modified tissue, which may cause higher losses of light on the surface. Fluorescence spectra showed different photosensitizer emissions for distinct operation modes. The different tissue composition can also induce changes on absorption and scattering properties, influencing the light penetration. The study showed significant necrosis formation beyond the limits of electrosurgery damage, making possible the conjugate use of ES and PDT.

Rego-Filho, Francisco G.; Vieira, Edson; Kurachi, Cristina; Bagnato, Vanderlei S.; de Araujo, Maria T.

2011-06-01

216

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

217

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

218

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

219

Effect of photodynamic therapy with hypocrellin B on apoptosis, adhesion, and migration of cancer cells.  

PubMed

Abstract Purpose: In the present study, we investigated effects of photodynamic therapy with hypocrellin B on apoptosis, adhesion, and migration of cancer cells in vitro. Materials and methods: Human ovarian cancer HO-8910 cell as a cancer model cell was incubated with hypocrellin B at a concentration of 2.5 ?M for 5 h and irradiated by light from a light-emitting diodes (LED) source. Cell apoptosis was analyzed by flow cytometry with annexin V/propidium iodide (PI) staining and nuclear staining 6 h after hypocrellin B photoirradiation. Cell adhesion was assessed using the 3-(4, 5-dimthylthiazol-2-yl)-2, 5 diphenyl-tetrazolium bromide (MTT) assay 4 h after photodynamic treatment. Cell migration was measured 48 h after photodynamic treatment. Results: Flow cytometry with annexin V/PI staining showed that early apoptotic and late apoptotic (necrotic) rates following photodynamic therapy with hypocrellin B markedly increased to 16.40% and 24.67%, respectively. Nuclear staining found nuclear condensation and typical apoptotic body in the treated cells. The number of cell migration was significantly decreased to 183 ± 28 after photodynamic therapy with hypocrellin B (p < 0.01). Light irradiation alone and hypocrellin B alone had no significant effect on cell migration. The cell adhesion inhibitory rate due to photodynamic action of hypocrellin B was 53.2 ± 1.8%, significantly higher than 2.7 ± 2.1% of light treatment alone and 1.0 ± 0.4% of hypocrellin B treatment alone (p < 0.01). Conclusion: The findings demonstrated that photodynamic therapy with hypocrellin B remarkably induced apoptosis and inhibited adhesion and migration of cancer cells in vitro. PMID:24661233

Jiang, Yuan; Leung, Albert Wingnang; Wang, Xinna; Zhang, Hongwei; Xu, Chuanshan

2014-07-01

220

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

221

Adjuvant Bisphosphonate Therapy in Postmenopausal Breast Cancer Patients  

PubMed Central

Summary Adjuvant bisphosphonate therapy is increasingly used in postmenopausal breast cancer patients. This is based on level-one evidence that bisphosphonates, particularly zoledronic acid, can effectively prevent cancer treatment-induced bone loss in breast cancer patients receiving estradiol-lowering endocrine therapies such as aromatase inhibitors. Furthermore, emerging data from large clinical trials suggest that additional anticancer benefits can be derived due to a positive impact on the bone marrow microenvironment.

Gnant, Michael

2010-01-01

222

Oral fluoropyrimidines in the adjuvant therapy of colon cancer  

Microsoft Academic Search

Oral chemotherapy offers several potential benefits over intravenous treatment, and the majority of patients would prefer\\u000a oral therapy provided that it does not compromise efficacy. We review the evidence that oral fluoropyrimidines can replace\\u000a intravenous 5-fluorouracil (5-FU) in the adjuvant therapy of colon cancer, without loss of efficacy, while at the same time\\u000a improving tolerability and reducing the use of

R. M. Glasspool; J. Cassidy

2006-01-01

223

Selective use of adjuvant radiation therapy in resectable colorectal adenocarcinoma  

Microsoft Academic Search

Colorectal cancer recurs within the operative field in 10–20 per cent of patients undergoing potentially curative surgery.\\u000a In certain subgroups, the recurrence rate is 20–50 per cent. There are some data to suggest either preoperative or postoperative\\u000a radiation therapy as an adjuvant to potentially curative surgery can reduce the local operative failure rate. However, since\\u000a radiation therapy has significant side

Alfred M. Cohen; Leonard L. Gunderson; Claude E. Welch

1981-01-01

224

Toluidine blue O-conjugated gold nanoparticles for photodynamic therapy of cultured colon cancer  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is an emerging technique for the treatment of cancerous and non-cancerous conditions. Gold nanoparticles (GNPs) possess unique physical and chemical properties which allow them to act as multifunctional agents in nanomedicine. GNP- photosensitizer conjugates have attracted increasing attention in drug delivery for photodynamic cancer therapy. In the present investigation, we prepared covalent conjugates of the photosensitizer Toluidine Blue O (TBO) and thiol protected GNPs. The suitability of TBO- GNPs conjugates for in vitro PDT was assayed using the SW480 Human colon adenocarcinoma cell line. Our results suggest that gold nanoparticle conjugates are an excellent vehicle for delivery of photosensitizer agents in the photodynamic therapy of cultured tumour cells.

Al-Majmaie, Rasoul; Alattar, Nebras; Zerulla, Dominic; Al-Rubeai, Mohamed

2012-05-01

225

Contrast enhanced-magnetic resonance imaging as a surrogate to map verteporfin delivery in photodynamic therapy  

NASA Astrophysics Data System (ADS)

The use of in vivo contrast-enhanced magnetic resonance (MR) imaging as a surrogate for photosensitizer (verteporfin) dosimetry in photodynamic therapy of pancreas cancer is demonstrated by correlating MR contrast uptake to ex vivo fluorescence images on excised tissue. An orthotopic pancreatic xenograft mouse model was used for the study. A strong correlation (r=0.57) was found for bulk intensity measurements of T1-weighted gadolinium enhancement and verteporfin fluorescence in the tumor region of interest. The use of contrast-enhanced MR imaging shows promise as a method for treatment planning and photosensitizer dosimetry in human photodynamic therapy (PDT) of pancreas cancer.

Samkoe, Kimberley S.; Bryant, Amber; Gunn, Jason R.; Pereira, Stephen P.; Hasan, Tayyaba; Pogue, Brian W.

2013-12-01

226

Canine treatment with SnET2 for photodynamic therapy  

NASA Astrophysics Data System (ADS)

Photodynamic therapy is a treatment technique that utilizes the photoactived species of a drug to destroy tumor tissue. To be successful, the drug must localize in tumor tissue preferentially over normal tissue and must be activated by light of a specific wavelength. Currently the only drug to be approved for clinical use is Heinatoporphyrin Derivative (HpD) although a series of new drugs are being developed for use in the near future. One of the drugs belongs to a class called purpurins which display absorp-' tions between 630-711 nm. Along with several other investigators, we are currently exploring the characteristics of a specific purpurin (SnET2) in normal and tumorous canine tissue. The use of this compound has demonstrated increased tumor control rates in spontaneous dog tumors. Preliminary pharmacokinetic studies have been performed on 6 normal beagle dogs. SnET2 (2 mg/kg) was injected intravenously over 10 minutes and blood was collected at 5, 15, 30, 45 minutes and at 1, 2, 4, 8, 12 and 24 hours following administration for determination of drug concentration and calculation of pharinacokinetic parameters. Skin biopsies were collected at 1, 4, 8, 12 and 24 hours. Dogs were euthanized at 24 hours and tissues (liver, kidney muscle, esophagus, stomach, duodenum, jejunum, ileura, colon, adrenal gland, thyroid, heart, lung, urinary bladder, prostate, pancreas, eye, brain) were collected for drug raeasurement. Drug was shown to persist in liver and kidney for a prolonged period of time coiapared to other tissues. Knowledge of the pharmacokinetic properties of the drug will greatly add to the ability to treat patients with effective protocols.

Frazier, Donita L.; Milligan, Andrew J.; Vo-Dinh, Tuan; Morgan, Alan R.; Overholt, Bergein F.

1990-07-01

227

Low dose mTHPC photodynamic therapy for cholangiocarcinoma  

NASA Astrophysics Data System (ADS)

Objective: Demonstration of whether a low dose of mTHPC (temoporfin , Foscan) is sufficient to induce an efficient clinical response in palliative PDT of non-resectable cholangiocarcinoma (CC), while showing a low side effect profile as compared to the standard Photofrin PDT. Materials and Methods: 13 patients (14 treatment sessions) with non-resectable CC were treated with stenting and PDT (3 mg Foscan per treatment, 0.032-0.063 mg/kg body weight, 652 nm, 50 J/cm). Fluorescence measurements were performed with a single bare fiber for 5/13 patients prior to PDT at the tumor site to determine the fluorescence contrast. For another 7/13 patients, long-term fluorescence-kinetics were measured on the oral mucosa to determine the time of maximal relative fluorescence intensity. Results: Foscan fluorescence could clearly be identified spectroscopically as early as 20 hours after administration. It was not significantly different between lesion and normal tissue within the bile duct. Fluorescence kinetics assessed at the oral mucosa were highest at 72-96 hours after administration. The DLI was therefore extended from 20 hours to approx. 70 hours for the last 5 patients treated. The treatment effect was promising with a median survival of 11 months for the higher grade tumors (Bismuth types III and IV). Local side effects occurred in one patient (pancreatitis), systemic side effects were much reduced compared to prior experience with Photofrin. Conclusion: Combined stenting and photodynamic therapy (PDT) performed with a low dose of Foscan results in comparable survival times relative to standard Photofrin PDT, while lowering the risk of side effects significantly.

Stepp, Herbert; Kniebühler, Gesa; Pongratz, Thomas; Betz, Christian S.; Göke, Burkhard; Sroka, Ronald; Schirra, Jörg

2013-06-01

228

Galactodendritic Phthalocyanine Targets Carbohydrate-Binding Proteins Enhancing Photodynamic Therapy  

PubMed Central

Photosensitizers (PSs) are of crucial importance in the effectiveness of photodynamic therapy (PDT) for cancer. Due to their high reactive oxygen species production and strong absorption in the wavelength range between 650 and 850 nm, where tissue light penetration is rather high, phthalocyanines (Pcs) have been studied as PSs of excellence. In this work, we report the evaluation of a phthalocyanine surrounded by a carbohydrate shell of sixteen galactose units distributed in a dendritic manner (PcGal16) as a new and efficient third generation PSs for PDT against two bladder cancer cell lines, HT-1376 and UM-UC-3. Here, we define the role of galacto-dendritic units in promoting the uptake of a Pc through interaction with GLUT1 and galectin-1. The photoactivation of PcGal16 induces cell death by generating oxidative stress. Although PDT with PcGal16 induces an increase on the activity of antioxidant enzymes immediately after PDT, bladder cancer cells are unable to recover from the PDT-induced damage effects for at least 72 h after treatment. PcGal16 co-localization with galectin-1 and GLUT1 and/or generation of oxidative stress after PcGal16 photoactivation induces changes in the levels of these proteins. Knockdown of galectin-1 and GLUT1, via small interfering RNA (siRNA), in bladder cancer cells decreases intracellular uptake and phototoxicity of PcGal16. The results reported herein show PcGal16 as a promising therapeutic agent for the treatment of bladder cancer, which is the fifth most common type of cancer with the highest rate of recurrence of any cancer.

Pereira, Patricia M. R.; Silva, Sandrina; Cavaleiro, Jose A. S.; Ribeiro, Carlos A. F.; Tome, Joao P. C.; Fernandes, Rosa

2014-01-01

229

Interstitial photodynamic therapy for the prostate: a canine feasibility study  

NASA Astrophysics Data System (ADS)

Prior to a possible clinical application of photodynamic therapy (PDT) for prostatic diseases such as benign prostatic hyperplasia and prostate cancer, optical properties of the prostate gland need to be studied. The specific objectives of this study were (1) to determine the light penetration depth, (2) to document the photosensitizer levels in the prostate, and (3) to document the lesion size after PDT. Sixteen dogs were injected with Photofrin II (1, 3 and 5 mg/kg) 24 hrs prior to laser application. After laparotomy and exposure of prostate, monochromatic light (630 nm, via an argon pumped dye laser) was applied through an isotropic fiber at 100 mw for a total dose of 400 joules. Continuous light fluence and temperature were documented. Prostates were harvested at 1 week and examined histologically for the lesion size. Four sham dogs were treated without Photofrin II. At Photofrin doses of 1, 3 and 5 mg/kg the mean prostatic Photofrin levels were 1.78 plus or minus 0.33, 1.47 plus or minus 0.08 and 1.95 plus or minus 0.44 (mu) gm/ml. The mean light penetration depths were 2.08, 1.37 and 1.64 mm respectively. Photofrin dose escalation (1, 3 and 5 mg/kg) increased the lesion size to radius of 4.1 plus or minus 0.9 mm, 4.4 plus or minus 0.8 mm and 6.3 plus or minus 0.9 mm. There were no lesions seen in sham dogs. These results demonstrate that light penetration in prostate is consistent and therapeutic levels of photosensitizer are achieved in prostatic tissue. Moreover, increasing size of the lesions were documented with dose escalation.

Shetty, Sugandh D.; Sirls, Larry T.; Chen, Qun; Hetzel, Fred W.; Cerny, Joseph C.

1996-05-01

230

Changes in tumor interstitial pressure induced by photodynamic therapy.  

PubMed

This study has examined the changes in tumor interstitial pressure exhibited during and after photodynamic therapy (PDT). The kinetics of these changes are marked by an initial decrease, followed by a rapid rise in tumor interstitial pressure. We have also employed two inhibitory agents to evaluate the different components of the pressure curve. Specially designed pressure chambers were seeded with chondrosarcoma and implanted subcutaneously in rats. Animals were injected with 0-50 mg/kg Photofrin II (i.v.) 7 days post-implantation and tumors were exposed to 0-540 J/cm2 630 nm 24 h later. Interstitial pressure was monitored via a transducer connected to the implanted chamber. Additional groups of animals were injected with either indomethacin (an inhibitor of thromboxane synthesis) or Ketanserin (a serotonin antagonist) before light treatment. Porphyrin doses of 10 mg/kg and above (135 J/cm2), or light doses of 135 J/cm2 and above (25 mg/kg Photofrin II) were effective in modifying interstitial pressure. Porphyrin doses greater than 25 mg/kg, or light doses greater than 270 J/cm2 produced no further increases in interstitial pressure. Animals given indomethacin (10 mg/kg i.p.) exhibited the initial decrease in pressure during light treatment, but showed no increase past baseline levels. Animals given Ketanserin (10 mg/kg i.p.) demonstrated no decrease in pressure during PDT, but showed the same elevations in pressure as controls. This suggests that two independent mechanisms account for the different components of the pressure curve, and that serotonin release may occur during PDT. PMID:1832229

Fingar, V H; Wieman, T J; Doak, K W

1991-06-01

231

New design of textile light diffusers for photodynamic therapy.  

PubMed

A homogeneous and reproducible fluence delivery rate during clinical photodynamic therapy (PDT) plays a determinant role in preventing under- or overtreatment. PDT applied in dermatology has been carried out with a wide variety of light sources delivering a broad range of more or less adapted light doses. Due to the complexities of the human anatomy, these light sources do not in fact deliver a uniform light distribution to the skin. Therefore, the development of flexible light sources would considerably improve the homogeneity of light delivery. The integration of plastic optical fiber (POF) into textile structures could offer an interesting alternative. In this article, a textile light diffuser (TLD) has been developed using POF and Polyester yarns. Predetermined POF macrobending leads to side emission of light when the critical angle is exceeded. Therefore, a specific pattern based on different satin weaves has been developed in order to improve light emission homogeneity and to correct the decrease of side emitted radiation intensity along POF. The prototyped fabrics (approximately 100 cm(2): 5×20 cm) were woven using a hand loom, then both ends of the POF were coupled to a laser diode (5 W, 635 nm). The fluence rate (mW/ cm(2)) and the homogeneity of light delivery by the TLD were evaluated. Temperature evolution, as a function of time, was controlled with an infrared thermographic camera. When using a power source of 5 W, the fluence rate of the TLD was 18±2.5 mw/cm(2). Due to the high efficiency of the TLD, the optical losses were very low. The TLD temperature elevation was 0.6 °C after 10 min of illumination. Our TLD meets the basic requirements for PDT: homogeneous light distribution and flexibility. It also proves that large (500 cm(2)) textile light diffusers adapted to skin, but also to peritoneal or pleural cavity, PDTs can be easily produced by textile manufacturing processes. PMID:23827556

Cochrane, Cédric; Mordon, Serge R; Lesage, Jean Claude; Koncar, Vladan

2013-04-01

232

Systemic toxicity in mice induced by localized porphyrin photodynamic therapy.  

PubMed

An unexpected high level of acute lethality has been documented following Photofrin II-mediated photodynamic therapy (PDT) treatments which were localized to the hind leg of normal and tumor-bearing mice. Doses of PDT which induced lethality (10 mg/kg Photofrin II, 200-500 J/cm2) were in the range of doses required to obtain murine tumor cures. The percentage of lethality was proportional to the total light dose but was inversely proportional to the dose rate of delivered light. Comparable levels of acute toxicity were observed in four pigmented mouse strains (C57BL/6J, C3H/HeJ, DBA/1, and DBA/2) and in two albino mouse strains (BALB/c and Swiss Webster). Decreased sensitivity to PDT-induced lethality was observed in two pigmented mouse strains (B10D2/OSN and B10D2/NSN). The administration of warfarin, aspirin, indomethacin, or antihistamine had significant protective effects in terms of decreasing PDT-induced lethality. However, injection of cobra venom factor (to deplete C3 and C5 of the complement system) did not alter the lethality mediated by PDT. Histological profiles obtained 24 h following PDT demonstrated vascular congestion in the liver, kidney, lung, and spleen. Significant decreases in removable blood volume, core temperature, and spleen weight were also observed within 24 h of localized PDT treatment. These results indicate that PDT-induced lethality is consistent with a traumatic shock syndrome and suggest that endogenous vasoactive mediators of shock such as prostaglandins, thromboxanes, and histamine are associated with the lethality induced by localized PDT in mice. PMID:2137023

Ferrario, A; Gomer, C J

1990-02-01

233

Pentamethylpyrromethene boron difluoride complexes in human ovarian cancer photodynamic therapy  

NASA Astrophysics Data System (ADS)

Quasiaromatic heterocycles (QAM) such as substituted 1 , 3 , 5 , 7 , 8-pentamethylpyrromethene boron difluorides (PMP-BF2) and - (dimethoxyphosphinylmethyl, methyl) bimane have been evaluated for their abilities to produce cellular toxicities when used in photodynamic therapy (PDT) for ovarian cancer. The most active QAH tested to date has been the disodiuxn salt of PMP-2,6-disulfonate--BF2 (PMPDS-BF2). Human ovarian cancer cells from fifteen different patients have been grown in culture. Cells were obtained from biopsy material and grown in RPMI medium with 10% FBA plus penicillin and streptomycin. Cells were harvested and as single cell suspensions exposed to PMP-BF2 complexes or bimanes in concentrations of 0.004-0.4 ug/106 cells/ml of medium. Initially the cells were exposed to the chemicals for 30 minutes in a 5% CO2 incubator (37°C) with gentle shaking. The cells were washed with plain RPMI medium, then resuspended in the enriched RPMI medium and exposed to a sunlamp for 10-20 minutes. Cells were then allowed to grow in an soft agar culture media at 37°C (5% C02) for 14 days. When compared to controls (only light or only chemicals) there was 100% inhibition of all cellular growth for PMPDSBF2 at the 0.4 ug/mi concentrations. There was variations in concentrations of the chemical needed to produce 100% inhibition when the 15 different ovarian cancer cell specimens were compared at all concentrations. PMP-BF2 complexes are characterized by extremely high extinction coefficients, superior laser activity and little if any triplet-triplet absorption. The biamanes share these properties however are less active in ovarian cancer cell The lasing properties of PMP-BF2, and bimanes will be compared to their PDT effectiveness.

Morgan, Lee R.; Chaudhuri, Aulena; Gillen, Laura E.; Boyer, Joseph H.; Wolford, Lionel T.

1990-07-01

234

The use of photodynamic therapy in bone marrow purging.  

PubMed

High-dose chemotherapy and autologous bone marrow transplantation are an effective combination for treating a number of malignant disorders. Clinical trials have demonstrated a potential role for this regimen in the management of acute leukemia and non-Hodgkin's lymphoma. Autologous bone marrow transplantation continues to be limited by high relapse rates, as compared with allogeneic bone marrow transplantation. Two factors are thought to account for this observation. First, autologous transplants lack the immunologic "graft-versus-host" advantage of allogeneic transplants. Second, autologous grafts have the possibility of tumor cell contamination. Methods to reduce tumor cell contamination in autografts include exposure to chemical agents or monoclonal antibodies; long-term marrow cultures; and immunologic manipulation, either with immunomagnetic devices or antibody/complement combinations. Photodynamic therapy (PDT) with porfimer sodium (Photofrin; manufactured by Lederle Parenterals, Carolina, Puerto Rico, under license from Quadra Logic Technologies, Inc, Vancouver, British Columbia, Canada) or benzoporphyrin derivative (BPD verteporfin; BPD-MA; BPD-Quadra Logic Technologies, Inc, Vancouver, British Columbia, Canada) may be an effective means of purging bone marrow. The ability of malignant cells to selectively accumulate photosensitizing agents may account for efficacy of PDT in bone marrow purging. The efficacy of porfimer sodium and BPD has been evaluated in cell lines known to express multidrug resistance (MDR), and the results compared with corresponding MDR-negative cell lines. Multidrug resistance-positive cell lines appear relatively resistant to BPD; porfimer sodium remains active. The reason for the differential effect of MDR positivity on the cytotoxicity of porfimer sodium and BPD is unclear, but is believed to be related to the larger size of the porfimer sodium molecule. Clinical trials evaluating PDT in bone marrow transplantation are under way. PMID:7992104

Mulroney, C M; Glück, S; Ho, A D

1994-12-01

235

Indocyanine green as a prospective sensitizer for photodynamic therapy of melanomas.  

PubMed

Spectroscopic, photochemical and biological properties of indocyanine green (ICG) are presented. Light over 800 nm is effectively absorbed by ICG. This property as well as photochemical behaviour of ICG make it a very suitable dye for photodynamic treatment of melanoma cells. Cytotoxicity of ICG itself and the effect of photodynamic therapy (PDT) were evaluated by following the growth of human (SKMEL 188) and mouse (S91) melanoma cells. The surviving fraction of the cells irradiated (lambda(ex) = 830 nm) vs non-irradiated, treated with the same dose of ICG, is significantly decreased (5- to 10-fold). These results show that ICG is a very promising dye for photodynamic therapy of melanomas. PMID:12362980

Urbanska, Krystyna; Romanowska-Dixon, Bozena; Matuszak, Zenon; Oszajca, Janusz; Nowak-Sliwinska, Patrycja; Stochel, Grazyna

2002-01-01

236

Tritolylporphyrin dimer as a new potent hydrophobic sensitizer for photodynamic therapy of melanoma.  

PubMed

We report the synthesis, photochemical and photophysical properties and preliminary studies on biological effect of a new tritolylporphyrin dimer (T-D). Absorption and emission properties of T-D suggest its possible use in photodynamic therapy. T-D is capable of singlet oxygen production with 0.8 quantum yield. It also has a high photostability. The photodynamic properties of the dimer were examined following the growth of SKMEL 188 (human melanoma) cells irradiated with red light (cut off < 630 nm). The surviving fraction of the cells decreased about 3-fold (vs. non-irradiated cells) for an 81 J/cm dose. Our results suggest that tritolylporphyrine dimer T-D may be an interesting hydrophobic sensitizer for photodynamic therapy. PMID:11440180

Drzewiecka, A; Urba?ska, K; Matuszak, Z; Pineiro, M; Arnaut, L G; Habdas, J; Ratuszna, A; Stochel, G

2001-01-01

237

Postoperative adjuvant therapy of breast cancer. Oncology Overview  

SciTech Connect

Oncology Overviews are a service of the International Cancer Research Data Bank (ICRDB) Program of the National Cancer Institute, intended to facilitate and promote the exchange of information between cancer scientists by keeping them aware of literature related to their research being published by other laboratories throughout the world. Each Oncology Overview represents a survey of the literature associated with a selected area of cancer research. It contains abstracts of articles which have been selected and organized by researchers associated with the field. Contents: Postoperative chemotherapy; Postoperative radiotherapy; Postoperative hormone therapy; Postoperative immunotherapy and chemoimmunotherapy; Postoperative multimodal therapy; Prognostic factors in postoperative adjuvant therapy.

Not Available

1984-12-01

238

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

239

Optical Dosimetry and Treatment Planning for Photodynamic Therapy  

NASA Astrophysics Data System (ADS)

Accurate dosimetry and treatment planning for photodynamic therapy (PDT) require knowledge of tissue optical properties and models of light propagation. We present techniques, based on reflectance and fluorescence spectroscopy, to examine these problems using analytical approximations and Monte Carlo (MC) simulations. We begin with studies that monitored PDT in mouse models using reflectance and fluorescence spectroscopy. In the first, spectroscopy informed the optimization of treatment parameters for methylene blue PDT, with dependencies on injection vehicle, drug-light interval, and fluence found. In the second, fluorescence photobleaching during Pc 4 PDT was examined for correlation to tumor response. Irradiance-dependent photobleaching was demonstrated, but was not predictive of tumor response. Next we outline the graphics processing unit enhanced MC model that was used to simulate light propagation in tissue. We demonstrate a number of source models that were used in subsequent experiments. We then focus on the recovery of optical properties from diffuse reflectance measurements by examining two studies. In the first study, diffuse reflectance measurements were made at the surface of human kidneys to extract optical properties, which were then used in MC simulations of interstitial PDT. We found that the optical properties measured make PDT feasible in human kidneys. We then examined the interstitial recovery of optical properties using a custom optical probe. This recovery was based on a MC model of the probe used, with a mean error of 6.5% in the determination of absorption. We examined fluorescence detection by cylindrical diffusing fibers using a MC model. This model predicted heterogeneous fluorescence detection, which was verified experimentally. Recovery of intrinsic fluorescence from point, interstitial measurements was demonstrated. This technique did not require a prori knowledge of the tissue optical properties, and was used to determine these values. Mean error of fluorophore concentration recovery was 12%, while mean error for background absorption was 23%. Finally, we demonstrate a treatment planning modality for interstitial PDT based on clinical imaging, optical spectroscopy, and MC simulations. This allows for individualized therapy based on the patient's anatomy and optical properties. We demonstrate optimization of diffuser placement, and show results for determination of deposited dose.

Baran, Timothy M.

240

Polymeric photosensitizer-embedded self-expanding metal stent for repeatable endoscopic photodynamic therapy of cholangiocarcinoma.  

PubMed

Photodynamic therapy (PDT) is a new therapeutic approach for the palliative treatment of malignant bile duct obstruction. In this study, we designed photosensitizer-embedded self-expanding nonvascular metal stent (PDT-stent) which allows repeatable photodynamic treatment of cholangiocarcinoma without systemic injection of photosensitizer. Polymeric photosensitizer (pullulan acetate-conjugated pheophorbide A; PPA) was incorporated in self-expanding nonvascular metal stent. Residence of PPA in the stent was estimated in buffer solution and subcutaneous implantation on mouse. Photodynamic activity of PDT-stent was evaluated through laserexposure on stent-layered tumor cell lines, HCT-116 tumor-xenograft mouse models and endoscopic intervention of PDT-stent on bile duct of mini pigs. Photo-fluorescence imaging of the PDT-stent demonstrated homogeneous embedding of polymeric Pheo-A (PPA) on stent membrane. PDT-stent sustained its photodynamic activities at least for 2 month. And which implies repeatable endoscopic PDT is possible after stent emplacement. The PDT-stent after light exposure successfully generated cytotoxic singlet oxygen in the surrounding tissues, inducing apoptotic degradation of tumor cells and regression of xenograft tumors on mouse models. Endoscopic biliary in-stent photodynamic treatments on minipigs also suggested the potential efficacy of PDT-stent on cholangiocarcinoma. In vivo and in vitro studies revealed our PDT-stent, allows repeatable endoscopic biliary PDT, has the potential for the combination therapy (stent plus PDT) of cholangiocarcinoma. PMID:25043500

Bae, Byoung-Chan; Yang, Su-Geun; Jeong, Seok; Lee, Don Haeng; Na, Kun; Kim, Joon Mee; Costamagna, Guido; Kozarek, Richard A; Isayama, Hiroyuki; Deviere, Jacques; Seo, Dong Wan; Nageshwar Reddy, D

2014-10-01

241

[Adjuvant for breast cancer chemo-endocrine therapy].  

PubMed

Early detection and improved therapy together have reduced the mortality for breast cancer in the world. A paradox in the management of patients with breast cancer is the observation that the majority appear to be curable at the time of initial surgery, yet a large number later experience relapse followed by death from disease. To combat this problem, systemic drug therapy in conjunction with surgery and radiation therapy is now standard for many patient subgroups, although the specific decision to use hormonal therapy, combination chemotherapy, or both remains complex and controversial. Adjuvant therapy for breast cancer is an area in constant evolution. Randomized clinical trials are the critical step leading to the identification of improved therapies, that will become our new "standards" of management. PMID:9530350

Taguchi, T

1998-03-01

242

Adjuvant therapy for patients with colorectal cancer  

Microsoft Academic Search

There are now excellent data that patients with stage III colon cancer or stage II and III rectal cancer live longer if they receive, respectively, systemic or regional and systemic therapy after surgery. In addition, disease-free survival, particularly freedom from the symptom of regional recurrence, in the high risk rectal cancer patient population has been markedly improved by application of

Glenn Steele

1995-01-01

243

[Laparoscopic surgery and adjuvant therapy for colon cancer].  

PubMed

At present, about 10% of all oncological procedures in the colon are carried out laparoscopically. Acceptance is increasing. After successful R0 resection, the rule for stage III patients is: adjuvant therapy is indicated regardless of age. Regimens containing oxaliplatin should be used. If there are contraindications for oxaliplatin, then fluoropyrimidine monotherapy is indicated, with oral fluoropyrimidines (capecitabine) being given precedence over infusional schemes. The use of 5-FU bolus regimens is regarded as obsolete. For stage II, the following applies: If an adjuvant chemotherapy is planned in these patients on the basis of the QUASAR data, then fluoropyrimidine monotherapy (e. g. capecitabine) can be given. Since patients whose tumours show a high frequency of microsatellite instability (MSI) do not benefit from a fluoropyrimidine monotherapy, the MSI status should be determined before choosing therapy. PMID:19546595

Kubicka, Stefan; Geissler, Michael; Bruch, Hans-Peter; Trarbach, Tanja

2009-01-01

244

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

245

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

2013-07-14

246

Curative effect of photodynamic therapy of pulse laser on cancer detected by computer  

Microsoft Academic Search

The computer diagnosis apparatus for human diseases is used to detect the curative effect of photodynamic therapy (PDT). It directly takes the electric signals from auricular acupuncture points of patients turns the signals into data and displays the data on the screen. Comparing the data with the critical point, it gives out the diagnosis of the condition of the disease.

Xiuzhen Sun

1993-01-01

247

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

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

Analysis of acute vascular damage after photodynamic therapy using benzoporphyrin derivative (BPD)  

Microsoft Academic Search

Benzoporphyrin derivative monoacid ring A (BPD-MA, verteporfin) is currently under investigation as a photosensitizer for photodynamic therapy (PDT). Since BPD exhibits rapid pharmacokinetics in plasma and tissues, we assessed damage to tumour and muscle microvasculature when light treatment for PDT was given at short times after injection of photosensitizer. Groups of rats with chondrosarcoma were given 2 mg kg-1 of

V H Fingar; P K Kik; P S Haydon; P B Cerrito; M Tseng; E Abang; T J Wieman

1999-01-01

250

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

251

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

252

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

253

MR Imaging-Guided Interstitial Photodynamic Laser Therapy for Advanced Head and Neck Tumors  

Microsoft Academic Search

Summary: Photodynamic therapy (PDT) is a site-specific tumor treatment involving the administration of a photo- sensitizer activated by the local application of light. In interstitial PDT (IPDT), multiple laser fibers are inserted into the depth of the tumor. Image guidance is essential for accurate, safe, and uniform light delivery. We report a novel technique of IPDT for advanced head and

H. Rolf Jager; Magali N. Taylor; Tamer Theodossy; Colin Hopper

254

Photodynamic therapy suppresses tumor growth in an in vivo model of human hemangioma.  

PubMed

The authors investigated the efficacy of photodynamic therapy against infantile hemangioma using a hemangioma animal model. Eighty-three hemangioma specimens from five children were implanted into nude mice. The gross and volume changes of the implants were evaluated for up to 13 weeks. The histological change of the implant was evaluated at 5 weeks after transplantation. Photodynamic therapy was performed between 6 and 10 weeks after transplantation. The photosensitizer uptake of the implant was evaluated at 24 h after photosensitizer administration. The implant response was evaluated at 0, 12, and 24 h after light delivery. The change in ATF3 levels, a transcription factor induced under severe hypoxic conditions, was investigated immediately after treatment. The implant volume increased slowly during the first 4 weeks and then involuted. At 5 weeks after transplantation, plump endothelial cells formed tightly packed sinusoidal channels, and the endothelial cells were positive for CD31 and GLUT1 expression. At 24 h after photosensitizer administration, confocal analysis showed that the photosensitizer was present within CD31-positive cells. The implant volume was significantly decreased in the treated implants compared with the untreated implants (p < 0.0001). At 24 h after light delivery, most cells had collapsed. ATF3 expression increased gradually and then reached a maximum level at 4 h after treatment. Photodynamic therapy was effective in the treatment of infantile hemangioma. Apoptosis, a major mechanism of hemangioma destruction in the early phase, might be caused by ischemic injury as well as direct effects of photodynamic therapy. PMID:23784382

Choi, Jaehoon; Kim, Woo Jung; Park, Sang Woo; Xu, Lianji; Kim, Sang-Hyon; Min, Hye Sook; Kwon, Geun-Yong; Cho, Chung-Hyun; Kim, Sukwha; Choi, Tae Hyun

2014-01-01

255

In vivo optical imaging to visualize photodynamic therapy-induced immune responses  

Microsoft Academic Search

Motivated by recent successes in growing intradermal tumors in the ears of mice and establishing the feasibility of in vivo confocal imaging of anatomic vessels in these tumors using fluorophore-conjugated antibodies to CD31, we are exploring a number of applications of optical fluorescence imaging in superficial murine tumor models in vivo. Immune responses induced by photodynamic therapy (PDT) are dynamic

Soumya Mitra; Thomas H. Foster

2009-01-01

256

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

2013-11-25

257

Adjuvant Endocrine Therapy in Early Postmenopausal Breast Cancer  

PubMed Central

Summary Five years of adjuvant tamoxifen treatment has been the gold standard for women with early hormone-responsive breast cancer. Results from two large phase III, adjuvant studies have indicated that the third-generation aro-matase inhibitors (AIs) letrozole and anastrozole offer greater protection against recurrence than tamoxifen in upfront substitution strategies in the first 5 years. Similarly, changeover to an AI (exemestane or anastrozole) after 2-3 years of tamoxifen has been more efficient to prevent recurrence than 5 years of tamoxifen. Most early breast cancer recurrences occur 5 or more years after surgery. Letrozole has been shown to offer greater protection against recurrence than placebo in the 5 years after a standard course of tamoxifen. The optimal adjuvant use (duration and sequencing) of AIs requires further investigation. Safety implications of treatment with these AIs for 5 years or more are closely monitored. The anticipated effects of estrogen deprivation on bone health may be treatable with bisphosphonates. Effects on the cardiovascular system, and other estrogen-sensitive systems such as the central nervous system, are currently examined. The AIs letrozole, anastrozole, and ex-emestane have recently replaced tamoxifen as the recommended adjuvant endocrine therapy, on the basis of greater efficacy and better tolerability.

Mundhenke, Christoph; Schem, Christian; Jonat, Walter

2008-01-01

258

Chemiluminescent Nanomicelles for Imaging Hydrogen Peroxide and Self-Therapy in Photodynamic Therapy  

PubMed Central

Hydrogen peroxide is a signal molecule of the tumor, and its overproduction makes a higher concentration in tumor tissue compared to normal tissue. Based on the fact that peroxalates can make chemiluminescence with a high efficiency in the presence of hydrogen peroxide, we developed nanomicelles composed of peroxalate ester oligomers and fluorescent dyes, called peroxalate nanomicelles (POMs), which could image hydrogen peroxide with high sensitivity and stability. The potential application of the POMs in photodynamic therapy (PDT) for cancer was also investigated. It was found that the PDT-drug-loaded POMs were sensitive to hydrogen peroxide, and the PDT drug could be stimulated by the chemiluminescence from the reaction between POMs and hydrogen peroxide, which carried on a self-therapy of the tumor without the additional laser light resource.

Chen, Rui; Zhang, Luzhong; Gao, Jian; Wu, Wei; Hu, Yong; Jiang, Xiqun

2011-01-01

259

Adjuvant therapy for patients with high-risk malignant melanoma.  

PubMed

The role of adjuvant therapy in the treatment of patients with high-risk malignant melanoma remains an area of intense investigation. The initial enthusiasm for high-dose interferon has been tempered by the results of more recent studies that allow for conflicting interpretations. Vaccine therapy trials have failed to clearly demonstrate a survival benefit, although several trials are currently ongoing. Recent studies of the role of chemotherapy suggest there may be combinations that have a survival benefit which deserve further study. This article will address patient selection and staging workup, and review options for treatment. PMID:12170442

McClay, Edward F

2002-08-01

260

The role of adjuvant therapy in non-metastatic RCC.  

PubMed

Renal cell carcinoma (RCC) presents as localized disease in 54% of the cases. For these patients, surgery is the primary curative treatment. Unfortunately, up to 65% of all patients show recurrent disease. For metastatic RCC non-specific immunotherapy is currently the treatment of choice. Nevertheless, several new modalities, e.g. WX-G250, oncophage and anti-angiogenic compounds like sunitinib and sorafenib are being explored with favorable results. Still, their place in the primary treatment of advanced RCC has yet to be determined. Because of the high percentage of recurrent disease, there is a need to identify these patients with conventional and molecular risk factors. Furthermore, adjuvant therapy to reduce risk of recurrence of RCC following nephrectomy is of clinical relevance. A review of recent literature was performed on the topics prognostic models, risk factors and adjuvant treatment for non-metastasized RCC. Combining classical risk factors for progression of RCC has shown to be effective for stratifying patients into risk groups. The UCLA integrated staging system (UISS) is the currently the only validated prognostic model. Whether molecular markers are able to better identify high-risk patients is still under investigation. Adjuvant therapy has been explored in the treatment for RCC and the use of non-specific cytokine regimens has so far not shown to be effective in the adjuvant setting. More specific therapies, e.g. WX-G250, oncophage and anti-angiogenic drugs are clinically active in patients with advanced RCC. Large randomized clinical trials with these drugs are currently ongoing to evaluate their effect in patients with localized RCC. PMID:16672131

Bleumer, Ivar; de Mulder, Pieter H M; Mulders, Peter F A

2006-04-01

261

The evolving role of adjuvant therapy in endometrial cancer.  

PubMed

Extra-fascial total hysterectomy and bilateral salpingo-oophorectomy with or without lymph node dissection is the initial treatment for endometrial cancer. Unresolved scientific controversy exists regarding the selection of patients who may benefit from lymphadenectomy, the magnitude of such benefit, and the role of adjuvant therapy. External pelvic irradiation has been shown to reduce loco-regional recurrences without improving survival. Meta-analyses of randomized trials indicate that external pelvic irradiation offers a significant benefit in terms of survival only in high-risk disease (i.e. stage Ic grade 3). Intermediate risk patients (i.e. stage Ib grade 3 disease), therefore, may be treated with adjuvant intravaginal brachytherapy alone to avoid the risk of side effects associated with pelvic irradiation. Overall, patients with clinically early endometrial cancer develop relapses in less than 20% of cases, mostly at distant sites. Randomized trials comparing adjuvant external pelvic irradiation versus adjuvant chemotherapy have shown conflicting clinical results. Chemotherapy seems to prevent or delay distant spread more than radiotherapy, while radiotherapy appears to prevent or delay local relapses more than chemotherapy, although these trends fail to achieve statistical significance. Recent evidence from a randomized trial indicates that sequential external pelvic irradiation with or without brachytherapy and platinum-based chemotherapy result in significantly better progression-free survival than radiotherapy alone in patients with high-risk endometrial cancer. Reliable surgical/pathological variables predictive of high risk of distant failure may be used to identify a subset of patients suitable for randomized trials of adjuvant chemotherapy with or without external irradiation. PMID:20418109

Gadducci, Angiolo; Greco, Carlo

2011-05-01

262

Using nanoparticles to enable simultaneous radiation and photodynamic therapies for cancer treatment.  

PubMed

This paper describes research into a new approach to cancer treatment through a combination of radiation and photodynamic therapies. The assumption is that supplementing conventional radiation therapy with photodynamic therapy (PDT) will enable the use of lower doses of radiation. Under this concept, scintillation or persistent luminescence nanoparticles with attached photosensitizers such as porphyrins are used as an in vivo agent for photodynamic therapy. The nanoparticle PDT agents are delivered to the treatment site. Upon exposure to ionizing radiation such as X-rays, the nanoparticles emit scintillation or persistent luminescence, which, in turn, activates the photosensitizers; as a consequence, singlet oxygen (1O2) is produced. Studies have shown that 1O2 can be effective in killing cancer cells. This is the conventional way in which PDT can augment the effectiveness of ionizing radiation. The innovation described in this study involves the use of in vivo luminescent nanoparticles so that an external light source is not required to support PDT. Consequently, application of the therapy can be more localized and the potential of damage to healthy cells is reduced. This new modality will provide an efficient, low-cost approach to PDT while still offering the benefits of augmented radiation therapy at lower doses. PMID:16736782

Chen, Wei; Zhang, Jun

2006-04-01

263

Status of adjuvant endocrine therapy for breast cancer  

PubMed Central

Adjuvant endocrine therapy reduces the risk of recurrence and death from breast cancer in women with hormone receptor-positive early breast cancer. Tamoxifen has been the standard therapy for decades, and this is still the case for pre-menopausal women. Ovarian suppression is of similar efficacy but currently there is no strong evidence for adding this to tamoxifen and the additional morbidity can be considerable. Results from two important trials addressing this issue are imminent. In post-menopausal women, aromatase inhibitors (AIs) (letrozole, anastrozole, or exemestane) are superior to tamoxifen in preventing recurrence but only letrozole has been shown to improve survival. The main gain is against high-risk cancers, and tamoxifen gives very similar benefit for low-risk disease. Traditionally, treatment has been given for around 5 years, but many women remain at risk of relapse for 10 years or more. The AIs, and more recently tamoxifen, have been shown to reduce further the risk of late recurrence in women still in remission after 5 years of tamoxifen if given for a further 5 years. The comparative benefits of these two options and the selection of patients most likely to benefit from long-term adjuvant endocrine therapy are important topics for further research, as is the optimum duration of AI therapy started upfront.

2014-01-01

264

Photodynamic Therapy Oxidative Stress as a Molecular Switch Controlling Therapeutic Gene Expression for the Treatment of Locally Recurrent Breast Carcinoma.  

National Technical Information Service (NTIS)

Photodynamic therapy (PDT) is a developing therapeutic modality which continues to show promise in the clinical treatment of cancer, including locally recurrent breast carcinoma. Our application is directly related to using novel molecular technologies to...

C. J. Gomer

2001-01-01

265

Photodynamic Therapy Oxidative Stress as a Molecular Switch Controlling Therapeutic Gene Expression for the Treatment of Locally Recurrent Breast Carcinoma.  

National Technical Information Service (NTIS)

Photodynamic therapy (PDT) is a developing therapeutic modality which continues to show promise in the clinical treatment of cancer, including locally recurrent breast carcinoma. Our application is directly related to using novel molecular technologies to...

C. Gomer

2000-01-01

266

Photodynamic Therapy Oxidative Stress as a Molecular Switch Controlling Therapeutic Gene Expression for the Treatment of Locally Recurrent Breast Carcinoma.  

National Technical Information Service (NTIS)

Photodynamic Therapy (PDT) is a developing therapeutic modality which continues to show promise in the clinical treatment of cancer, including locally recurrent breast carcinoma. Our application is directly related to using novel molecular technologies to...

C. J. Gomer

2002-01-01

267

5-aminolevulinic acid in photodynamic diagnosis and therapy of urological malignancies  

NASA Astrophysics Data System (ADS)

Completeness and certainty of tumor detection are very important issues in clinical oncology. Recent technological developments in ultrasound, radiologic and magnetic resonance imaging diagnostics are very promising, but could not improve the detection rate of early stage malignancies. One of the most promising new approaches is the use of 5-aminolevulinic acid, a potent photosensitizer, in photodynamic diagnosis and therapy. 5-aminolevulinic acid is meanwhile a well-established tool in the photodynamic diagnosis of bladder cancer. It has been shown to improve the sensitivity of detection of superficial tumors and carcinoma in situ, which enables to reduce the risk of tumor recurrence related to undetected lesions or incomplete transurethral resection of the primary lesions. The use of 5-aminolevulinic acid is steadily expanding in diagnostics of urological malignancies. First clinical results are now reported in detection of urethral and ureteral lesions as well as in urine fluorescence cytology. Furthermore, due to the selective accumulation in transitional cell carcinoma of the bladder, 5-aminolevulinic acid may be an ideal candidate for photodynamic therapy in superficial bladder cancer. Summarizing the data of multiple clinical trials, 5-aminolevulinic acid is a promising agent in photodynamic diagnostics and treatment of superficial bladder cancer.

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

2003-06-01

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

2013-12-01

269

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

270

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

271

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

272

Second malignancies after breast cancer: The impact of adjuvant therapy  

PubMed Central

Second malignant neoplasms (SMNs) are potentially life-threatening late sequelae of the adjuvant therapy for breast cancer (BC). The increased risk of SMNs is associated with adjuvant chemotherapy (development of secondary acute myeloid leukemia and myelodysplastic syndrome) and hormonal therapy (risk of uterine cancer secondary to tamoxifen treatment). Previous studies have demonstrated an increased risk of SMNs associated with alkylating agents, topoisomerase-II inhibitors, granulocyte-stimulating factors and estrogen receptor modulators. Furthermore, analytical investigations have demonstrated that BC patients may be at an increased risk of leukemia following chemotherapy. In addition, correlations between an increased dose of hormonal therapy and solid tumor risk have been identified. Considering the ongoing alterations in the treatment of BC, with respect to lowering the daily as well as the cumulative dose of chemo-therapeutic agents, it is anticipated that leukemias will have a considerably lower impact on BC survivors in the future. However, diligent follow-up is required to accurately evaluate the long-term risks associated with chemotherapy.

DONG, CHUNHUI; CHEN, LING

2014-01-01

273

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

274

Preclinical studies of photodynamic therapy of intracranial tissues  

NASA Astrophysics Data System (ADS)

The applicability and limitations of the photodynamic threshold model were investigated for an intracranial tumor (VX2) and normal brain tissues in a rabbit model. Photodynamic threshold values for four different photosensitizers, i.e., Photofrin, 5(delta) -aminolaevulinic acid (5(delta) -ALA) induced Protoporphyrin IX (PPIX), Tin Ethyl Etiopurpurin (SnET2), and chloroaluminum phthalocyanine (AlClPc), were determined based on measured light fluence distributions, macroscopic photosensitizer concentration in various brain structures, and histologically determined extent of tissue necrosis following PDT. For Photofrin, AlClPc, and SnET2, normal brain displayed a significantly lower threshold value than VX2 tumor. For 5(delta) -ALA induced PPIX and SnET2 no or very little white matter damage, equalling to very high or infinite threshold values, was observed. Additionally, the latter two photosensitizers showed significantly lower uptake in white matter compared to other brain structures and VX2 tumor. Normal brain structures lacking a blood- brain-barrier, such as the choroid plexus and the meninges, showed high photosensitizer uptake for all photosensitizers, and, hence, are at risk when exposed to light. Results to date suggest that the photodynamic threshold values iares valid for white matter, cortex and VX2 tumor. For clinical PDT of intracranial neoplasms 5(delta) -ALA induced PPIX and SnET2 appear to be the most promising for selective tumor necrosis.However, the photosensitizer concentration in each normal brain structure and the fluence distribution throughout the treatment volume and adjacent tissues at risk must be monitored to maximize the selectivity of PDT for intracranial tumors.

Lilge, Lothar D.; Sepers, Marja; Park, Jane; O'Carroll, Cindy; Pournazari, Poupak; Prosper, Joe; Wilson, Brian C.

1997-05-01

275

Magnetic chitosan nanoparticles as a drug delivery system for targeting photodynamic therapy.  

PubMed

Photodynamic therapy (PDT) has become an increasingly recognized alternative to cancer treatment in clinic. However, PDT therapy agents, namely photosensitizer (PS), are limited in application as a result of prolonged cutaneous photosensitivity, poor water solubility and inadequate selectivity, which are encountered by numerous chemical therapies. Magnetic chitosan nanoparticles provide excellent biocompatibility, biodegradability, non-toxicity and water solubility without compromising their magnetic targeting. Nevertheless, no previous attempt has been reported to develop an in vivo magnetic drug delivery system with chitosan nanoparticles for magnetic resonance imaging (MRI) monitored targeting photodynamic therapy. In this study, magnetic targeting chitosan nanoparticles (MTCNPs) were prepared and tailored as a drug delivery system and imaging agents for PS, designated as PHPP. Results showed that PHPP-MTCNPs could be used in MRI monitored targeting PDT with excellent targeting and imaging ability. Non-toxicity and high photodynamic efficacy on SW480 carcinoma cells both in vitro and in vivo were achieved with this method at the level of 0-100 microM. Notably, localization of nanoparticles in skin and hepatic tissue was significantly less than in tumor tissue, therefore photosensitivity and hepatotoxicity can be attenuated. PMID:19420486

Sun, Yun; Chen, Zhi-Long; Yang, Xiao-Xia; Huang, Peng; Zhou, Xin-Ping; Du, Xiao-Xia

2009-04-01

276

Magnetic chitosan nanoparticles as a drug delivery system for targeting photodynamic therapy  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) has become an increasingly recognized alternative to cancer treatment in clinic. However, PDT therapy agents, namely photosensitizer (PS), are limited in application as a result of prolonged cutaneous photosensitivity, poor water solubility and inadequate selectivity, which are encountered by numerous chemical therapies. Magnetic chitosan nanoparticles provide excellent biocompatibility, biodegradability, non-toxicity and water solubility without compromising their magnetic targeting. Nevertheless, no previous attempt has been reported to develop an in vivo magnetic drug delivery system with chitosan nanoparticles for magnetic resonance imaging (MRI) monitored targeting photodynamic therapy. In this study, magnetic targeting chitosan nanoparticles (MTCNPs) were prepared and tailored as a drug delivery system and imaging agents for PS, designated as PHPP. Results showed that PHPP-MTCNPs could be used in MRI monitored targeting PDT with excellent targeting and imaging ability. Non-toxicity and high photodynamic efficacy on SW480 carcinoma cells both in vitro and in vivo were achieved with this method at the level of 0-100 µM. Notably, localization of nanoparticles in skin and hepatic tissue was significantly less than in tumor tissue, therefore photosensitivity and hepatotoxicity can be attenuated.

Sun, Yun; Chen, Zhi-long; Yang, Xiao-xia; Huang, Peng; Zhou, Xin-ping; Du, Xiao-xia

2009-04-01

277

Photodynamic therapy in the treatment of choroidal neovascularization complicating central serous chorioretinopathy.  

PubMed

We report the favorable anatomic and functional outcome of photodynamic therapy with verteporfin in a case of chronic central serous chorioretinopathy complicated with choroidal neovascularization (CNV). This 37-year-old Chinese male with bilateral chronic central serous chorioretinopathy presented with central scotoma, reduced vision and metamorphopsia in his right eye. Fluorescein angiography (FA) disclosed macular hemorrhage, exudate and subfoveal classic CNV. Photodynamic therapy (PDT) with verteporfin was applied to the CNV according to standard protocol with 2.2-mm spot size. Best-corrected visual acuity (BCVA) improved from 6/20 to 6/10 1 month after PDT. BCVA recovered to 6/7.5 without leakage on FA 3 months after PDT. Neither recurrent CNV lesion nor new hemorrhage was noted over 12 months of follow-up. Short-term results suggest that PDT with verteporfin for CNV secondary to central serous chorioretinopathy is a safe and effective treatment modality. PMID:19762322

Yang, Chang-Sue; Chen, Kuan-Chieh; Lee, Shui-Mei; Lee, Fenq-Lih

2009-09-01

278

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

279

Photodynamic Therapy for Basal Cell Carcinoma in Recessive Dystrophic Epidermolysis Bullosa  

PubMed Central

A 22-year-old male with recessive dystrophic epidermolysis bullosa with a large superficial and nodular basal cell carcinoma on his right forehead was treated with photodynamic therapy. The treatment was well tolerated, and the site healed well. Patients with epidermolysis bullosa are at increased risk of developing skin cancers, particularly squamous cell carcinomas. However, basal cell carcinomas are rare in recessive dystrophic epidermolysis bullosa. As patients with epidermolysis bullosa have recurrent blistering and poor wound healing, surgery may not be the optimal choice in treating skin cancers. We present this case to highlight that photodynamic therapy may be a helpful and safe technique in the treatment of superficial skin cancers in patients with epidermolysis bullosa, as an alternative to more radical methods.

Lee, Myn Wee; Varigos, George; Foley, Peter; Ross, Gayle

2011-01-01

280

Predictive model for photodynamic therapy with gold nanoparticles as vehicle for the photosensitizer delivery  

NASA Astrophysics Data System (ADS)

Photodynamic Therapy offers multiple advantages to treat nonmelanoma skin cancer compared to conventional treatment techniques such as surgery, radiotherapy or chemotherapy. Among these advantages are particularly relevant its noninvasive nature, the use of non ionizing radiation and its high selectivity. However the therapeutic efficiency of the current clinical protocol is not complete in all the patients and depends on the type of pathology. Emerging strategies to overcome its current shortcomings include the use of nanostructures that can act as carriers for conventional photosensitizers and improve the treatment selectivity and provide a controlled release of the photoactive agent. In this work, a model for photodynamic therapy combined with gold nanocarriers for a photosensitizer commonly used in dermatology is presented and applied to a basal cell carcinoma in order to predict the cytotoxic agent spatial and temporal evolution.

Salas-García, I.; Fanjul-Vélez, F.; Ortega-Quijano, N.; Arce-Diego, J. L.

2013-06-01

281

Rose-bengal-conjugated gold nanorods for in vivo photodynamic and photothermal oral cancer therapies.  

PubMed

Gold nanorods (GNRs) conjugated with rose bengal (RB) molecules exhibit efficient singlet oxygen generation when illuminated by 532 nm green light and high photothermal efficiency under 810 nm near-infrared (NIR) irradiation. In vitro experiments show that reactive oxygen species generated by green light and hyperthermia produced by NIR light constitute two different mechanisms for cancer cell death. The RB-GNRs also exhibit improved photodynamic efficacy by enhancing the uptake of RB by cancer cells. In vivo experiments are conducted on hamster cheek pouches to resemble the human oral cancer conditions more accurately to assess the therapeutic effectiveness. Compared to the single photodynamic therapy (PDT) or photothermal therapy (PTT), the RB-GNRs with combined PDT-PTT capabilities provide better therapeutic effects against oral cancer and have large potential in cancer treatment. PMID:24331707

Wang, Beike; Wang, Jia-Hong; Liu, Qian; Huang, Hao; Chen, Ming; Li, Kaiyang; Li, Chengzhang; Yu, Xue-Feng; Chu, Paul K

2014-02-01

282

Combination therapy with antiangiogenic treatment and photodynamic therapy for the nude mouse bearing U87 glioblastoma.  

PubMed

The objective of this study was to evaluate the effects of combination therapy with photodynamic therapy (PDT) and a novel antiangiogenic regimen using monoclonal antibodies against both vascular endothelial growth factor receptors (VEGFR)-1 (MF1) and VEGFR-2 (DC101) on intracranial glioblastoma xenografts in nude mice. Nude mice bearing intracerebral U87 glioblastoma were treated with PDT and the antiangiogenic regimen (MF1 and DC101) either alone or in combination, while those left untreated served as tumor controls. Tumor volume and animal survival time were analyzed to evaluate the outcome of different treatment modalities. In addition, the immunohistochemical expression of VEGF in the brain adjacent to the tumor, von Willebrand factor (vWF), apoptotic, and proliferative markers in the tumor area were examined. PDT or MF1 + DC101 alone significantly reduced the tumor volume and prolonged the survival time of glioma-implanted animals. Combined therapy markedly reduced tumor volume and increased survival time with significantly better outcomes than both monotherapies. Both vWF and VEGF levels significantly increased after PDT while they both significantly decreased after antiangiogenic treatment, compared with no treatment. PDT plus antiangiogenic treatment led to significant decreases in both vWF and VEGF expression, compared with PDT alone. Either PDT or antiangiogenic treatment alone significantly increased tumor cell apoptosis compared with no treatment, while combination therapy resulted in further augmentation of apoptosis. Antiangiogenic treatment with or without PDT significantly decreased tumor cell proliferation, compared with either no treatment or PDT alone. In summary, we demonstrate both significant inhibition of tumor growth and extended survival of mice treated by the combination therapy with PDT and antiangiogenic agents, compared with each single treatment, suggesting that the combination therapy may be a promising strategy to improve clinical outcomes in glioblastoma. PMID:18173712

Jiang, Feng; Zhang, Xuepeng; Kalkanis, Steven N; Zhang, Zhenggang; Yang, Hongyan; Katakowski, Mark; Hong, Xin; Zheng, Xuguang; Zhu, Zhenping; Chopp, Michael

2008-01-01

283

Adjuvant therapy for hepatocellular carcinoma: current situation and prospect.  

PubMed

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide, accounting for 90% of primary liver cancers, and its incidence is still increasing. While the curative treatment for HCC is surgical resection and liver transplantation, most patients are in advanced stage, and lose the chance of surgery. Other palliative treatments include radiofrequency ablation, transarterial embolization, chemotherapy, and radiotherapy. Although there are so many treatments, the prognosis of HCC is still very poor. A major obstacle for the treatment for HCC is the high frequency of tumor recurrence even after curative resection and liver transplantation. Since HCC is frequently resistant to conventional chemotherapy and radiotherapy, clinical development of novel therapeutic agents against HCC has begun in earnest. Thus far, a series of adjuvant therapies for HCC have emerged, including small molecular target agents, monocolonal antibodies, microRNA, and Chinese herbal medicine. Some agents such as sorafenib have shown an advantage in prolonging the overall survival time, and has been approved by FDA for the treatment of advanced HCC. In this article we review the current situation and prospects of adjuvant therapies for HCC. PMID:24071575

Wang, Zhigang; Zhang, Guofeng; Wu, Jiacheng; Jia, Mingku

2013-08-01

284

Using antimicrobial adjuvant therapy in cancer treatment: a review  

PubMed Central

Recent clinical and pre-clinical data demonstrate that adjuvant antimicrobial therapy is beneficial in cancer treatment. There could be several reasons for this effect, which include treating cancer associated bacteria and viruses, prophylaxis of post-chemotherapy infections due to immunosuppression, and antiproliferative effect of certain antimicrobials. Targeting cancer associated viruses and bacteria with antimicrobial agents is currently used for gastric, cervical, hematopoietic, liver and brain cancer. However this treatment is effective only in combination with conventional therapies. Antimicrobials can also have a direct antiproliferative and cytotoxic effect, and can cause apoptosis. Moreover, some antimicrobials are known to be helpful in overcoming side effects of drugs commonly used in cancer treatment. Chemotherapy related bacteremia and neutropenia can be overcome by the appropriately timed use of antimicrobials. This review summarizes the data on the effects of antivirals and antibiotics on cancer treatment and describes their mechanisms.

2012-01-01

285

Immunological and Viral Factors Associated with the Response of Vulval Intraepithelial Neoplasia to Photodynamic Therapy1  

Microsoft Academic Search

Topical 5-aminolevulinic acid-based photodynamic therapy (PDT) has produced complete response rates of >90% for nonmelanoma skin car- cinomas, which are mostly human papillomavirus (HPV) negative. Using a similar treatment protocol, we observed a short-term response in only one third (10 of 32) of high-grade vulval intraepithelial neoplasia (VIN 2-3) lesions. Unifocal lesions were found more responsive than multifocal and pigmented

El-Said Abdel-Hady; Pierre Martin-Hirsch; Maggie Duggan-Keen; Peter L. Stern; James V. Moore; Gerald Corbitt; Henry C. Kitchener; Ian N. Hampson

286

Nanoparticle-mediated combination chemotherapy and photodynamic therapy overcomes tumor drug resistance  

Microsoft Academic Search

Tumor cells utilize multiple mechanisms to evade the cytotoxic effect of anticancer drugs. Overexpression of drug efflux transporters like P-glycoprotein (P-gp), altered tumor microenvironment, and sequestration of the drug in acidic cellular organelles are important factors that prevent the accumulation of effective cellular concentrations of anticancer drug. The hypothesis of this research is that nanoparticle-mediated combination chemotherapy and photodynamic therapy

Ayman Abed Khdair

2008-01-01

287

Therapeutic effects of systemic photodynamic therapy in a leukemia animal model using A20 cells  

Microsoft Academic Search

Photodynamic therapy (PDT) is attracting attention because of its noticeable inhibitory effects on the growth of dermatological\\u000a and other solid tumors. Here, we studied the use of PDT in systemic diseases such as leukemia, lymphoma, and metastatic cancer,\\u000a for which tumor formation areas cannot be clearly compartmentalized. We developed a systemic PDT method and examined its effect\\u000a in a leukemia

Lan Ying Wen; Su-Mi Bae; Heung-Jae Chun; Kye-Shin Park; Woong Shick Ahn

288

Photodynamic Therapy with 5-Aminolevulinic Acid Induces Apoptosis and Caspase Activation in Malignant T Cells  

Microsoft Academic Search

Background: Preliminary studies have suggested that photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) can improve\\u000a psoriasis and mycosis fungoides, two diseases where normal or malignant T cells play a central role. Objectives: To determine\\u000a if ALA-PDT induces apoptosis and caspase activation in Jurkat cells, a malignant T-cell line. Methods: Jurkat cells were incubated\\u000a with ALA in the presence of [14C]-thymidine

Faten Gad; Gilles Viau; Michele Boushira; Richard Bertrand; Robert Bissonnette

2001-01-01

289

Massive exudative retinal detachment following photodynamic therapy for retinal hemangioma in von Hippel-Lindau Syndrome.  

PubMed

Photodynamic therapy (PDT) is a common treatment on retinal capillary hemangioma. We applied PDT to a patient with von Hippel-Lindau(VHL) syndrome and she developed severe massive exudative retinal detachment the next day, which is a rare complication for PDT. After intraocular anti-VEGF agent and peribulbar dexamethasone several times to the patient, her subretinal fluid disappeared and hemangiomas atrophied. Treatment with Anti-VEGF agent and corticosteroid is effective for such complication. PMID:24632330

Chen, Yao; Liu, Hong; Zhang, Kun; Gao, Ling

2014-06-01

290

Modified porphyrin-brucine conjugated to gold nanoparticles and their application in photodynamic therapy.  

PubMed

Two porphyrin-brucine quaternary ammonium salts were immobilized on gold nanoparticles and their suitability for both in vitro and in vivo photodynamic therapy (PDT) was assayed using the basaloid squamous cell carcinoma PE/CA-PJ34 cell line. In vitro PDT experiments revealed that the gold nanoparticle-bound conjugates were less effective than unbound conjugates in killing cells. However, the same conjugates were more effective in reducing tumor size in vivo, with complete tumor regression observed. PMID:20485822

Záruba, Kamil; Králová, Jarmila; Rezanka, Pavel; Poucková, Pavla; Veverková, Lenka; Král, Vladimír

2010-07-21

291

Photodynamic therapy as a novel antimicrobial strategy against biofilm-based nosocomial infections: study protocols.  

PubMed

Hospital-acquired infections (HAIs), also known as nosocomial infections, are one of the most serious health-care issues currently influencing health-care costs. Among them, those sustained by microbial biofilm represent a major public health concern. Here, we describe the experimental protocols for microbial biofilm inactivation relying on antimicrobial photodynamic therapy (APDT) as a new strategy for the control of these kinds of infections. PMID:24664842

Giuliani, Francesco

2014-01-01

292

Vascular regrowth following photodynamic therapy in the chicken embryo chorioallantoic membrane  

Microsoft Academic Search

Photodynamic therapy (PDT) induces damage to the endothelium, which can lead to increased vascular permeability and, under\\u000a intensive PDT conditions, even to platelet aggregation, vasoconstriction, and blood flow stasis. Eventually, ischemia, hypoxia,\\u000a and inflammation can occur, resulting in angiogenesis. We studied the sequence of the vascular events after Visudyne®-PDT in the chicken chorioallantoic membrane (CAM) at day 11 of development.

Patrycja Nowak-SliwinskaJudy; Judy R. van Beijnum; Maaike van Berkel; Hubert van den Bergh; Arjan W. Griffioen

2010-01-01

293

Multifunctional hybrid nanoparticles for two-photon fluorescence imaging and photodynamic therapy  

Microsoft Academic Search

We review our work on several strategies to elaborate multifunctional nanoparticules for two-photon imaging or\\/and photodynamic therapy. Our first strategy is based on the incorporation of two-photon hydrophobic fluorophors in bio-compatible pluronic micelles using the mini-emulsion technique. Our second strategy is based on fluorescent organic nanocrystal grown in silicate spheres. These core-shell hybrid nanoparticles are obtained by a spray-drying process

Patrice L. Baldeck; Mathieu Maurin; Cecile Philipot; Soraya Zaiba; Thibault Gallavardin; Olivier Maury; Chantal Andraud; Fabien Dubois; Alain Ibanez; Frédéric Lerouge; Stéphane Parola; Olivier Stephan; Baudwin van der Sanden

2011-01-01

294

Randomised clinical trial of intravitreal Avastin vs photodynamic therapy and intravitreal triamcinolone: long-term results  

Microsoft Academic Search

PurposeTo compare 1-year functional and anatomic outcomes of intravitreal bevacizumab (IVB) and photodynamic therapy plus intravitreal triamcinolone (PDT+IVTA) combination in patients with neovascular age-related macular degeneration (AMD).MethodsIn this prospective, randomised, controlled clinical trial, 28 patients were included. All patients were randomised 1 : 1 to 0.04 ml\\/1 mg of IVB or PDT plus same day 0.1 ml\\/4 mg IVTA (PDT+IVTA).

S Sacu; S Michels; F Prager; G Weigert; R Dunavoelgyi; W Geitzenauer; C Pruente; U Schmidt-Erfurth

2009-01-01

295

Antibacterial activity of methyl aminolevulinate photodynamic therapy in the treatment of a cutaneous ulcer.  

PubMed

We describe a 79-year-old female with a chronic venous ulceration infected by Staphylococcus aureus and Enterococcus faecalis and not responsive to conventional treatments. The patient was treated with Methyl-Aminolaevulinate Photodynamic Therapy (MAL-PDT). After four weeks the cutaneous swabs become negative and we observed a significant clinical improvement. Therefore we suppose that MALPDT could represent a valid therapeutic option in the treatment of infected chronic ulcers. PMID:21978711

Devirgiliis, V; Panasiti, V; Fioriti, D; Anzivino, E; Bellizzi, A; Cimillo, M; Curzio, M; Melis, L; Roberti, V; Gobbi, S; Liteo, P; Richetta, A G; Calvieri, S; Chiarini, F; Nicosia, R; Pietropaolo, Valeria

2011-01-01

296

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

297

Infrared light utilized for photodynamic therapy by activation of rare earth phosphors for visible light generation  

Microsoft Academic Search

Introduction: Photodynamic therapy (PDT) is a treatment for cancer requiring activation of a photosensitizer for light-mediated tumor cytotoxicity. PDT is limited by tissue penetration because visible light is required for photosensitizer activation. SunstonesTM are rare-earth phosphors which up-convert energy from infrared wavelengths to emit higher energy in the visible spectrum. We utilized this unique characteristic to generate light of appropriate

Joshua E. Collins; Thiru V. Lakshman; Jarod E. Finlay; Ajith Kumar; Howard Bell; Ba T. Nguyen; Valery Belov; Jun Luo; Joseph S. Friedberg

2007-01-01

298

Kinetic Modeling of FDG uptake in rat tumors During photodynamic therapy  

Microsoft Academic Search

The aim of this work was to assess by kinetic modeling the effects of the photodynamic therapy (PDT) of cancer in two mammary adenocarcinoma tumors implanted in the axillary areas of rats. One tumor served as control while the other was treated with red light 24 hours after administration of two types of photosensitizers: AlPcS4 (n = 4) and ZnPcS2

M. Bentourkia; V. Berard; P. Boubacar; J. E. van Lier; R. Lecomte

2006-01-01

299

PET kinetic modeling of rat tumors simultaneously treated with photodynamic therapy: A reference tissue model  

Microsoft Academic Search

The aim of this work was to assess by kinetic modeling the effects of the photodynamic therapy (PDT) of cancer in two mammary adenocarcinoma tumors implanted in the axillary areas of rats. One tumor served as control while the other was treated with red light 24 hours after administration of two types of photosensitizers: AlPcS4 and ZnPcS2. PET scans were

Pate Boubacar; M'hamed Bentourkia; Otman Sarrhini; Johan E. van Lier; Roger Lecomte

2008-01-01

300

Photodynamic therapy efficacy and tissue distribution of hypericin in a mouse P388 lymphoma tumor model  

Microsoft Academic Search

The phototherapeutic properties and tissue distribution of hypericin were investigated in DBA\\/2 mice bearing subcutaneously transplanted P388 lymphoma cells. The efficacy of the photodynamic therapy (PDT) 2 h after administration of hypericin (2, 5, or 20 mg\\/kg, i.p., 120 J\\/cm2, 595 nm) was substantially greater than the efficacy after a 24 h interval. PDT with Photofrin (5 mg\\/kg, i.p., 24-h

Bin Chen; Peter A de Witte

2000-01-01

301

Fluorescence Resonance Energy Transfer Reveals a Binding Site of a Photosensitizer for Photodynamic Therapy1  

Microsoft Academic Search

Phthalocyanine (Pc) 4, like many photosensitizers for photodynamic therapy (PDT), localizes to intracellular membranes, especially mitochon- dria. Pc 4-PDT photodamages Bcl-2 and Bcl-xL, antiapoptotic proteins interacting with the permeability transition pore complex that forms at contact sites between the inner and outer mitochondrial membranes. These complexes and the inner membrane are unique in containing the phospholipid cardiolipin. Nonyl-acridine orange (NAO)

Rachel L. Morris; Kashif Azizuddin; Minh Lam; Jeffrey Berlin; Anna-Liisa Nieminen; Malcolm E. Kenney; Anna C. S. Samia; Clemens Burda; Nancy L. Oleinick

302

A case of small cell lung cancer treated with chemoradiotherapy followed by photodynamic therapy  

Microsoft Academic Search

Here, we present the case of a 51-year-old man with limited-stage small cell lung cancer (LS-SCLC) who received concurrent chemoradiotherapy and photodynamic therapy (PDT). The patient was diagnosed as having LS-SCLC with an endobronchial mass in the left main bronchus. Following concurrent chemoradiotherapy, a mass remaining in the left lingular division was treated with PDT. Clinical and histological data indicate

J E Lee; H S Park; S S Jung; S Y Kim; J O Kim

2009-01-01

303

Adjuvant therapy of stage II colorectal cancer – who will benefit from treatment?  

Microsoft Academic Search

Summary  Adjuvant treatment of stage II colon cancer remains an issue of controversy. Though there is evidence indicating that adjuvant\\u000a therapy is associated with a limited survival benefit, large clinical trials published so far did not provide enough evidence\\u000a to regard adjuvant therapy of stage II colon cancer as standard of care. The ultimate clinical decision should be based on\\u000a the

H. Zwierzina

2008-01-01

304

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

305

Photosensitizer-Conjugated Silica-Coated Gold Nanoclusters for Fluorescence Imaging-Guided Photodynamic Therapy  

PubMed Central

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.

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

2013-01-01

306

Cold water and pauses in illumination reduces pain during photodynamic therapy: a randomized clinical study.  

PubMed

Pain is the main acute adverse event during photodynamic therapy of skin lesions. The objective of this randomized study was to evaluate the pain-relieving effect of pauses and cooling during illumination. Twenty-four patients with actinic keratoses were treated with photodynamic therapy in two symmetrical areas and cooled with either cold-water-spray or cold-water-pack (CoolPack). Treatment areas were cooled during either the first or second period of illumination, which were separated by a 3-min pause in illumination. Pain intensity was scored from 0 to 10. Water-spray reduced the mean pain score by 1.2 points (p=0.030) and CoolPack by 1.3 points (p=0.007) during the first half of the illumination. Pain intensity decreased during the pause by 3.7 points in water-spray patients (p<0.0001) and 3.0 points in CoolPack patients (p<0.0001). In conclusion, cooling resulted in a minor reduction in pain intensity, while adding the intermediate pause in illumination reduced the pain considerably. Use of pauses and cooling during illumination is an easy and inexpensive way to make photodynamic therapy more tolerable for the patient. PMID:19325998

Wiegell, Stine Regin; Haedersdal, Merete; Wulf, Hans Christian

2009-01-01

307

Phenylthio-substituted phthalocyanines as new photosensitizers for photodynamic therapy  

NASA Astrophysics Data System (ADS)

Current work is devoted to investigation of tetra-3-phenylthio-tetra-5-t-butylphthalocyanine [(PhS) 4(t-Bu) 4PcH II], aluminium hydroxyde tetra-3-phenylthiophthalocyanine [(PhS) 4PcAlOH] and zinc tetra-3-phenylthiophthalocyanine [(PhS) 4PcZn] as potential photosensitizers of near-infrared range. Investigations were performed on F I mice bearing Erlich tumor. Photosensitizers were administered intravenously in liposomal form at doses of 4-10 mg/kg. Dynamic and selectivity of sensitizers' accumulation in tumor were estimated in vivo from fluorescence and absorption spectra of sensitized tissue. Photosensitizers have shown high selectivity of accumulation in tumor comparing to normal tissue of mice. Maxima of selectivity for (PhS) 4(t-Bu) 4PcH II, (PhS) 4PcZn and (PhS) 4PcAlOH achieve the values up to 2.5:1, 5:1 and 8:1 respectively. All photosensitizers completely clear from the normal tissue in 7-8 days. For PDT investigations tumors were irradiated using 732 nm laser with power density of 100-500 mW/cm2 and light dose density up to 400 J/cm2. The photodynamic efficiency was estimated using the parameter of tumor growth inhibition (TGI). All photosensitizers had shown high photodynamic efficiency of relatively large tumors. PDT using (PhS) 4PcAlOH and (PhS) 4(t-Bu) 4PcH II caused pronounced TGI exceeding 80%. Using (PhS) 4PcZn caused moderate TGI of 60%. Investigations have shown that liposomal forms of phenylthiosubstituted phthalocyanine derivatives may be used to develop new efficient photosensitizers for PDT.

Meerovich, Igor G.; Derkacheva, Valentina M.; Meerovich, Gennady A.; Oborotova, Natalia A.; Smirnova, Zoya S.; Polozkova, Alevtina P.; Kubasova, Irina Yu.; Lukyanets, Evgeny A.; Baryshnikov, Anatoly Yu.

2007-02-01

308

Cancer therapy improvement with mesoporous silica nanoparticles combining photodynamic and photothermal therapy.  

PubMed

In this work, we develop novel mesoporous silica composite nanoparticles (hm-SiO2(AlC4Pc)@Pd) for the co-delivery of photosensitizer (PS) tetra-substituted carboxyl aluminum phthalocyanine (AlC4Pc) and small Pd nanosheets as a potential dual carrier system to combine photodynamic therapy (PDT) with photothermal therapy (PTT). In the nanocomposite, PS AlC4Pc was covalently conjugated to a mesoporous silica network, and small Pd nanosheets were coated onto the surface of mesoporous silica by both coordination and electrostatic interaction. Since small Pd nanosheets and AlC4Pc display matched maximum absorptions in the 600-800 nm near-infrared (NIR) region, the fabricated hm-SiO2(AlC4Pc)@Pd nanocomposites can generate both singlet oxygen and heat upon 660 nm single continuous wavelength (CW) laser irradiation. In vitro results indicated that the cell-killing efficacy by simultaneous PDT/PTT treatment using hm-SiO2(AlC4Pc)@Pd was higher than PDT or PTT treatment alone after exposure to a 660 nm CW-NIR laser. PMID:24971525

Zhao, Z X; Huang, Y Z; Shi, S G; Tang, S H; Li, D H; Chen, X L

2014-07-18

309

Photodynamic therapy with recombinant adenovirus AdmIL-12 enhances anti-tumour therapy efficacy in human papillomavirus 16 (E6/E7) infected tumour model  

PubMed Central

Immunotherapy with photodynamic therapy (PDT) offers great promise as a new alternative for cancer treatment; however, its use remains experimental. Here we investigated the utility of adenoviral delivery of interleukin-12 (AdmIL-12) as an adjuvant for PDT in mouse tumour challenge model. PDT was performed by irradiating Radachlorin in C57BL/6 mice transplanted with TC-1 cells. PDT plus AdmIL-12 treatment for tumour suppression as well as specific immune responses were evaluated with the following tests: in vitro and in vivo tumour growth inhibition, interferon-? (IFN-?) and tumour necrosis factor-? (TNF-?) assay, and cytotoxic T lymphocyte (CTL) assay. Direct intratumoral injection of AdmIL-12 resulted in a significant suppression of tumour growth compared to the control group. Treatment of PDT along with AdmIL-12 further enhanced antitumour effects significantly higher than either AdmIL-12 or PDT alone. This combined treatment resulted in complete regression of 9-mm sized tumour in every animal. We also evaluated immune responses induced by these treatments. Combined treatment significantly increased the production level of IFN-? and TNF-? compared with that by AdmIL-12 or PDT alone. PDT plus AdmIL-12 enhanced antitumour immunity through increased expansion of the CTL subset mediated by CD8+ T cells. Taken together, these results indicate that the high anti-cancer activity of PDT with AdmIL-12 is a powerful tool against cancer therapy and is a promising subject for further investigation.

Park, Eun Kyung; Bae, Su-Mi; Kwak, Sun-Young; Lee, Sung Jong; Kim, Yong-Wook; Han, Chan-Hee; Cho, Hyun-Jung; Kim, Kyung Tae; Kim, Young-Jae; Kim, Hyun-Jung; Ahn, Woong Shick

2008-01-01

310

Photosensitizer-loaded magnetic nanoemulsion for use in synergic photodynamic and magnetohyperthermia therapies of neoplastic cells.  

PubMed

In this study a magnetic nanoemulsion (MNE) was developed from a mixture of two components, namely biodegradable surfactants and biocompatible citrate-coated cobalt ferrite-based magnetic fluid, for entrapment of Zn(II)-Phthalocyanine (ZnPc), the latter a classical photosensitizer (PS) species used in photodynamic therapy (PDT) procedures. The sample's stability was evaluated as a function of time using photocorrelation spectroscopy (PCS) for determination of the average hydrodynamic diameter, diameter dispersion and zeta potential. The ZnPc-loaded magneto nanoemulstion (ZnPc/MNE) formulation was evaluated in vitro assays to access the phototoxicity and the effect of application of AC magnetic fields (magnetohyperthermia damage) after incubation with J774-A1 macrophages cells. Darkness toxicity, phototoxicity and AC magnetic field exposures revealed an enhancement response for combined photodynamic and magnetohyperthermia (MHT) processes, indicating the presence of the synergic effect. PMID:19198320

Primo, Fernando L; Rodrigues, Marcilene M A; Simioni, Andreza Ribeiro; Lacava, Zulmira G M; Morais, Paulo C; Tedesco, Antonio C

2008-11-01

311

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

312

Photodynamic therapy in a teenage girl with xeroderma pigmentosum type C.  

PubMed

Despite aggressive sun protection, most individuals with xeroderma pigmentosum (XP) develop cutaneous neoplasia, including actinic keratoses. We describe the case of a 16-year-old girl with XP type C treated safely with photodynamic therapy (PDT). Although there is little if any evidence in the literature supporting the use of aminolevulinic acid PDT in individuals with XP, they may be the ideal candidates for PDT treatment because the profound post-treatment photosensitivity and strict post-therapy sun avoidance necessitated by PDT treatment is already part of the everyday lifestyle of people with XP. PMID:22277026

Larson, David M; Cunningham, Bari B

2012-01-01

313

Endonyx toenail onychomycosis caused by Trichophyton rubrum: treatment with photodynamic therapy based on methylene blue dye*  

PubMed Central

This study shows the effectiveness of photodynamic therapy based on methylene blue dye for the treatment of endonyx toenail onychomycosis. Four patients with endonyx onychomycosis caused by Trichophyton rubrum were treated with 2% methylene blue aqueous solution irradiated with light emission diode at 630 nm and an energy density of 36 J/cm2 for 6 months at 2-week intervals. The preliminary study showed the effectiveness of this therapy in the treatment of endonyx onychomycosis, and also indicated that the disease can be caused by T. rubrum.

Souza, Linton Wallis Figueiredo; Souza, Simone Vilas Trancoso; Botelho, Ana Cristina de Carvalho

2013-01-01

314

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

315

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

316

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

317

Adjuvant androgen deprivation therapy augments cure and long-term cancer control in men with poor prognosis, nonmetastatic prostate cancer  

Microsoft Academic Search

Historically, adjuvant androgen deprivation therapy has been viewed as a palliative treatment option for patients with poor-prognosis non-metastatic prostate cancer. In addition, guidelines from bodies such as the European Association of Urology and American Society for Clinical Oncology do not specifically categorize adjuvant hormonal therapy as being curative in intent. We propose that adjuvant androgen deprivation therapy should now be

N. Fleshner; T. E. Keane; C. A. Lawton; P. F. A. Mulders; H. Payne; S. S. Taneja; T. Morris

2008-01-01

318

Novel LED array used for photodynamic therapy (PDT)  

NASA Astrophysics Data System (ADS)

Light Sciences Corporation has developed a novel LED array that was designed and manufactured to treat large bulky tumors. We describe our LED design process, culminating in the manufacture of a flexible silicone catheter currently under investigation in a Phase 1 clinical trial. The performance characteristics of the wire-bonded die to a flexible polyimide substrate forming a linear array are discussed. The LED array consists of 100 die arranged asymmetrically on the substrate with 50 LED's on either side producing up to 60mW total optical power at 38°C (500mA) over a spectral bandwidth 645-670nm FWHM. The LED's are encapsulated within biocompatible silicon for interstitial placement within the treatment tissue. The effect of time, temperature and humidity on the device performance was investigated. Optical power ranged from -2.5% to +0.5% of the normalized original power over 50 hours in 100% RH within the control group. Over a temperature range of 35°C to 50°C the optical power decreased at a rate of 0.56% per °C. Preliminary non-clinical experiments carried out in normal swine muscle demonstrate a significant treatment zone and are consistent with threshold models for photodynamic effect.

Daly, Steven R.; Zheng, Frank; Krouse, Mike; Guo, Zihong; Mahoney, Paula; McIlroy, Brian W.

2003-07-01

319

Postoperative adjuvant therapy for completely resected early-stage non-small cell lung cancer  

Microsoft Academic Search

Consensus on adjuvant therapy for completely resected non-small cell lung cancer until 2002 was as follows. (1) There was no significant impact of postoperative adjuvant chemotherapy based on meta-analysis and previous clinical trials. (2) Confirmatory studies are necessary in large-scale prospective clinical trials. However, recent mega trials have introduced epoch-making changes for postoperative adjuvant chemotherapy in clinical practice since ASCO

Harubumi Kato; Masahiro Tsuboi; Yasufumi Kato; Norihiko Ikeda; Tetsuya Okunaka; Chikuma Hamada

2005-01-01

320

Population Pharmacokinetics of the Photodynamic Therapy Agent 2-(1- Hexyloxyethyl)-2-devinyl Pyropheophorbide-a in Cancer Patients1  

Microsoft Academic Search

Photodynamic therapy is an effective and often curative treatment for certain solid tumors. The porphyrin-based photosensitizer Photofrin, the only Food and Drug Administration-approved drug for this therapy, suffers from certain disadvantages: its complex chemical nature; retention by skin (leading to protracted cutaneous photosensitivity); and less than optimal photophysical properties. In this study, we examine the popula- tion pharmacokinetics and cutaneous

David A. Bellnier; William R. Greco; Gregory M. Loewen; Hector Nava; Allan R. Oseroff; Ravindra K. Pandey; Takaaki Tsuchida; Thomas J. Dougherty

2003-01-01

321

Efficacy of photodynamic therapy against larvae of Aedes aegypti: confocal microscopy and fluorescence-lifetime imaging  

NASA Astrophysics Data System (ADS)

Recently a few demonstration on the use of Photodynamic Reaction as possibility to eliminate larvae that transmit diseases for men has been successfully demonstrated. This promising tool cannot be vastly used due to many problems, including the lake of investigation concerning the mechanisms of larvae killing as well as security concerning the use of photosensitizers in open environment. In this study, we investigate some of the mechanisms in which porphyrin (Photogem) is incorporated on the Aedes aegypti larvae previously to illumination and killing. Larvae at second instar were exposed to the photosensitizer and after 30 minutes imaged by a confocal fluorescence microscope. It was observed the presence of photosensitizer in the gut and at the digestive tract of the larva. Fluorescence-Lifetime Imaging showed greater photosensitizer concentration in the intestinal wall of the samples, which produces a strong decrease of the Photogem fluorescence lifetime. For Photodynamic Therapy exposition to different light doses and concentrations of porphyrin were employed. Three different light sources (LED, Fluorescent lamp, Sun light) also were tested. Sun light and fluorescent lamp shows close to 100% of mortality after 24 hrs. of illumination. These results indicate the potential use of photodynamic effect against the LARVAE of Aedes aegypti.

de Souza, L. M.; Pratavieira, S.; Inada, N. M.; Kurachi, C.; Corbi, J.; Guimarães, F. E. G.; Bagnato, V. S.

2014-03-01

322

Silicon naphthalocyanines derivatives: delivery systems as modulators of pharmacokinetics and photodynamic therapy (PDT) outcomes  

NASA Astrophysics Data System (ADS)

Photodynamic therapy of neoplastic tissues is a new treatment modality that combines the in- vivo administration of a photosensitizer followed by its excitation with visible light, which leads to a photochemical reaction and tissue destruction. Naphthalocyanine derivatives are a class of second-generation photosensitizers that have excellent prospects as photodynamic therapeutic agents. Relevant to these types of applications are their photochemical properties, their tumor-localizing abilities, and their ability to elicit photodynamic responses. Bis(di- isobutyloctadecylsiloxy)silicon 2,3-naphthalocyanine (isoBOSINC) illustrates some of the above promising photoproperties: absorption in the red at 776 nm with an extinction coefficient greater than 105 M-1 cm-1, a triplet state lifetime of 331 microseconds and singlet oxygen yields of approximately 0.20. Due to their high degree of hydrophobicity, metallonaphthalocyanines require a variety of approaches before they can be administered to cells in vitro or injected in vivo. One approach is the selection of solubilizing agents or vehicles such as a solution of Tween 80 in saline or emulsions of Cremophor EL in saline. This paper describes studies in (a) drug uptake by tumors and other tissues as a function of isoBOSINC's dose; (b) drug levels in normal versus tumor-bearing rats; (c) in-vitro photostability of isoBOSINC; (d) effects of delivery systems on photosensitizer tissue levels and pharmacokinetics, and PDT outcome.

Kreimer-Birnbaum, Martha; Zuk, Maria M.; Rihter, Boris D.; Kenney, Malcolm E.; Rodgers, Michael A.

1996-01-01

323

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

324

Novel Methods to Incorporate Photosensitizers Into Nanocarriers for Cancer Treatment by Photodynamic Therapy  

PubMed Central

Objective A hydrophobic photosensitizer, 2-[1-hexyloxyethyl]-2-devinyl pyropheophorbide-a (HPPH), was loaded into nontoxic biodegradable amine functionalized polyacrylamide (AFPAA) nanoparticles using three different methods (encapsulation, conjugation, and post-loading), forming a stable aqueous dispersion. Each formulation was characterized for physicochemical properties as well as for photodynamic performance so as to determine the most effective nanocarrier formulation containing HPPH for photodynamic therapy (PDT). Materials and Methods HPPH or HPPH-linked acrylamide was added into monomer mixture and polymerized in a microemulsion for encapsulation and conjugation, respectively. For post-loading, HPPH was added to an aqueous suspension of pre-formed nanoparticles. Those nanoparticles were tested for optical characteristics, dye loading, dye leaching, particle size, singlet oxygen production, dark toxicity, in vitro photodynamic cell killing, whole body fluorescence imaging and in vivo PDT. Results HPPH was successfully encapsulated, conjugated or post-loaded into the AFPAA nanoparticles. The resultant nanoparticles were spherical with a mean diameter of 29 ± 3 nm. The HPPH remained intact after entrapment and the HPPH leaching out of nanoparticles was negligible for all three formulations. The highest singlet oxygen production was achieved by the post-loaded formulation, which caused the highest phototoxicity in in vitro assays. No dark toxicity was observed. Post-loaded HPPH AFPAA nanoparticles were localized to tumors in a mouse colon carcinoma model, enabling fluorescence imaging, and producing a similar photodynamic tumor response to that of free HPPH in equivalent dose. Conclusions Post-loading is the promising method for loading nanoparticles with hydrophobic photosensitizers to achieve effective in vitro and in vivo PDT. Lasers Surg. Med. 43:686–695, 2011.

Wang, Shouyan; Fan, Wenzhe; Kim, Gwangseong; Hah, Hoe Jin; Lee, Yong-Eun Koo; Kopelman, Raoul; Ethirajan, Manivannan; Gupta, Anurag; Goswami, Lalit N.; Pera, Paula; Morgan, Janet; Pandey, Ravindra K.

2013-01-01

325

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

326

Impact of Selection Bias on the Utilization of Adjuvant Therapy for Pancreas Adenocarcinoma  

Microsoft Academic Search

Background  Improved outcomes have been associated with the use of adjuvant therapy after resection of pancreas adenocarcinoma. However,\\u000a the frequency with which patients receive adjuvant therapy and the factors impacting its use remain largely undefined. We\\u000a hypothesized that nonutilization of adjuvant therapy was primarily associated with patient comorbidity and onset of postoperative\\u000a complications.\\u000a \\u000a \\u000a \\u000a Methods  A prospectively maintained database was reviewed to identify

Andrew J. Russ; Sharon M. Weber; Robert J. Rettammel; David M. Mahvi; Layton F. Rikkers; Clifford S. Cho

2010-01-01

327

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

NASA Astrophysics Data System (ADS)

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.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. Electronic supplementary information (ESI) available: More data on singlet oxygen generation capability of Au NRs, RB and ICG under one- and two-photon excitation; extinction spectra of Au NRs/CTAB and Au NRs/PVP dispersed in DI water; stability of Au NRs/PVP dispersed in DMEM and EB fluorescence imaging of Au NRs/PVP and RB-loaded HeLa cells without laser irradiation; viability of cancer cells in the presence of Au NRs after CW laser irradiation at 808 nm; fs laser induced temperature change; effect of aggregation of Au NRs on singlet oxygen generation. See DOI: 10.1039/c2nr32196c

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

2012-11-01

328

Should Adjuvant Therapy Remain the Standard of Care for Patients With Resected Adenocarcinoma of the Pancreas?  

Microsoft Academic Search

Adenocarcinoma of the pancreas continues to be a formidable disease. In the United States, patients who have had resected disease are generally offered adjuvant chemoradiation. The current National Comprehensive Cancer Network practice guidelines uniformly support this practice. We reviewed seven selected series to evaluate the efficacy of adjuvant therapy for patients who had resected adenocarcinoma of the pancreas. Current evidence-based

Quyen D. Chu; Nikhil Khushalani; Miland M. Javle; Harold O. Douglass; John F. Gibbs

2003-01-01

329

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

330

Who Benefits From Adjuvant Radiation Therapy for Gastric Cancer? A Meta-Analysis  

SciTech Connect

Purpose: Large randomized trials have demonstrated significant survival benefits with the use of adjuvant chemotherapy or chemoradiation therapy for gastric cancer. The importance of adjuvant radiation therapy (RT) remains unclear. We performed an up-to-date meta-analysis of randomized trials testing the use of RT for resectable gastric cancer. Methods and Materials: We searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials for randomized trials testing adjuvant (including neoadjuvant) RT for resectable gastric cancer. Hazard ratios describing the impact of adjuvant RT on overall survival (OS) and disease-free survival (DFS) were extracted directly from the original studies or calculated from survival curves. Pooled estimates were obtained using the inverse variance method. Subgroup analyses were performed to determine whether the efficacy of RT varies with chemotherapy use, RT timing, geographic region, type of nodal dissection performed, or lymph node status. Results: Thirteen studies met all inclusion criteria and were used for this analysis. Adjuvant RT was associated with a significant improvement in both OS (HR = 0.78, 95% CI: 0.70-0.86, P<.001) and DFS (HR = 0.71, 95% CI: 0.63-0.80, P<.001). In the 5 studies that tested adjuvant chemoradiation therapy against adjuvant chemotherapy, similar effects were seen for OS (HR = 0.83, 95% CI: 0.67-1.03, P=.087) and DFS (HR = 0.77, 95% CI: 0.91-0.65, P=.002). Available data did not reveal any subgroup of patients that does not benefit from adjuvant RT. Conclusion: In randomized trials for resectable gastric cancer, adjuvant RT provides an approximately 20% improvement in both DFS and OS. Available data do not reveal a subgroup of patients that does not benefit from adjuvant RT. Further study is required to optimize the implementation of adjuvant RT for gastric cancer with regard to patient selection and integration with systemic therapy.

Ohri, Nitin, E-mail: ohri.nitin@gmail.com [Department of Radiation Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States)] [Department of Radiation Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States); Garg, Madhur K. [Department of Radiation Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States)] [Department of Radiation Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States); Aparo, Santiago; Kaubisch, Andreas [Department of Medical Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States)] [Department of Medical Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States); Tome, Wolfgang [Department of Radiation Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States)] [Department of Radiation Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States); Kennedy, Timothy J. [Department of Surgical Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States)] [Department of Surgical Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States); Kalnicki, Shalom; Guha, Chandan [Department of Radiation Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States)] [Department of Radiation Oncology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York (United States)

2013-06-01

331

Near infrared light-triggered drug generation and release from gold nanoparticle carriers for photodynamic therapy.  

PubMed

A photoprecursor Pc 227 is covalently bound onto gold nanoparticles (Au NPs) to produce the known photodynamic therapy (PDT) drug Pc 4 upon 660 nm photoirradiation. The photochemical formation of the photoproduct Pc 4 is identified by spectroscopy, chromatography, and mass spectrometry and its PDT efficacy is equal to Pc 4 when administered non-covalently by Au NPs, with the added benefit of improved covalent delivery and targeted NIR-triggered release from the covalent Pc 227-Au NP conjugate, while during transport the attached Pc 227 is quenched by the Au NP and PDT inactivated. PMID:24515950

Cheng, Yu; Doane, Tennyson L; Chuang, Chi-Hung; Ziady, Assem; Burda, Clemens

2014-05-14

332

Near Infrared Light-Triggered Drug Generation and Release from Gold Nanoparticle Carriers for Photodynamic Therapy  

PubMed Central

A photoprecursor Pc 227 is covalently bound onto gold nanoparticles (Au NPs) to produce the known photodynamic therapy (PDT) drug Pc 4 upon 660 nm photoirradiation. The photochemical formation of the photoproduct Pc 4 is identified by spectroscopy, chromatography, and mass spectrometry and its PDT efficacy is equal to Pc 4 when administered non-covalently by Au NPs, with the added benefit of improved covalent delivery and targeted NIR-triggered release from the covalent Pc 227-Au NP conjugate, while during transport the attached Pc 227 is quenched by the Au NP and PDT inactivated.

Cheng, Yu; Doane, Tennyson L.; Chuang, Chi-Hung; Ziady, Assem; Burda, Clemens

2014-01-01

333

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

334

Multifunctional hybrid nanoparticles for two-photon fluorescence imaging and photodynamic therapy  

NASA Astrophysics Data System (ADS)

We review our work on several strategies to elaborate multifunctional nanoparticules for two-photon imaging or/and photodynamic therapy. Our first strategy is based on the incorporation of two-photon hydrophobic fluorophors in bio-compatible pluronic micelles using the mini-emulsion technique. Our second strategy is based on fluorescent organic nanocrystal grown in silicate spheres. These core-shell hybrid nanoparticles are obtained by a spray-drying process from sol-gel solutions. Our third strategy consists in the encapsulation of hydrophilic molecules in the water core of gold nanospheres. They are obtained by a stabilized emulsion in biphasic liquid-liquid medium without surfactant.

Baldeck, Patrice L.; Maurin, Mathieu; Philipot, Cecile; Zaiba, Soraya; Gallavardin, Thibault; Maury, Olivier; Andraud, Chantal; Dubois, Fabien; Ibanez, Alain; Lerouge, Frédéric; Parola, Stéphane; Stephan, Olivier; van der Sanden, Baudwin

2011-02-01

335

Oleic Acid as Optimizer of the Skin Delivery of 5-Aminolevulinic Acid in Photodynamic Therapy  

Microsoft Academic Search

\\u000a Purpose  In photodynamic therapy (PDT), topically applied aminolevulinic acid (5-ALA) is converted to protoporphyrin IX (PpIX), which\\u000a upon light excitation induces tumor destruction. To optimize 5-ALA-PDT via improving the highly hydrophilic 5-ALA limited\\u000a penetration into the skin, we propose the use of the known skin penetration enhancer, oleic acid (OA).\\u000a \\u000a \\u000a \\u000a Methods  In vitro skin penetration and retention of 5-ALA (1% w\\/w) were measured

Maria Bernadete Riemma Pierre; Eduardo Ricci Jr; Antonio Cláudio Tedesco; Maria Vitória Lopes Badra Bentley

2006-01-01

336

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

337

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\\u000a of a specific wavelength. We report a novel delivery method—intra-arterial drug delivery for PDT of the prostate—in a canine\\u000a model.\\u000a \\u000a \\u000a \\u000a Methods  To evaluate drug distribution, the prostatovesical artery was selectively cannulated and photosensitizers alone or in conjunction\\u000a with 99m-technetium-labeled macro-aggregated albumin (99mTc-MAA) were injected via

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

2008-01-01

338

A method for video-assisted thoracoscopic photodynamic therapy (VAT-PDT).  

PubMed

A technique is described for application of photodynamic therapy (PDT) to peripheral pulmonary and other intrathoracic malignant tumours. For video-assisted thoracoscopic-PDT we advocate the use of the flexible fibreoptic bronchoscope through an appropriately placed port. This, together with the standard thoracoscope and attached monitor can provide three-dimensional visualisation of the intrathoracic lesion and more importantly allow the accurate delivery of laser light to the tumour. At the present time we have successfully used this method without complication in three patients with advanced inoperable disease. PMID:17670074

Moghissi, Keyvan; Dixon, Kate; Thorpe, J Andrew C

2003-09-01

339

Combined effects of singlet oxygen and hydroxyl radical in photodynamic therapy with photostable bacteriochlorins: evidence from intracellular fluorescence and increased photodynamic efficacy in vitro.  

PubMed

Sulfonamides of halogenated bacteriochlorins bearing Cl or F substituents in the ortho positions of the phenyl rings have adequate properties for photodynamic therapy, including strong absorption in the near-infrared (?(max) ? 750 nm, ? ? 10(5) M(-1) cm(-1)), controlled photodecomposition, large cellular uptake, intracellular localization in the endoplasmic reticulum, low cytotoxicity, and high phototoxicity against A549 and S91 cells. The roles of type I and type II photochemical processes are assessed by singlet oxygen luminescence and intracellular hydroxyl radical detection. Phototoxicity of halogenated sulfonamide bacteriochlorins does not correlate with singlet oxygen quantum yields and must be mediated both by electron transfer (superoxide ion, hydroxyl radicals) and by energy transfer (singlet oxygen). The photodynamic efficacy is enhanced when cellular death is induced by both singlet oxygen and hydroxyl radicals. PMID:22285766

D?browski, Janusz M; Arnaut, Luis G; Pereira, Mariette M; Urba?ska, Krystyna; Simões, Sérgio; Stochel, Gra?yna; Cortes, Luísa

2012-04-01

340

Neo-adjuvant therapy for hepatocellular carcinoma before liver transplantation: Where do we stand?  

PubMed Central

Liver transplantation (LT) for hepatocellular carcinoma (HCC) within Milan criteria is a widely accepted optimal therapy. Neo-adjuvant therapy before transplantation has been used as a bridging therapy to prevent dropout during the waiting period and as a down-staging method for the patient with intermediate HCC to qualify for liver transplantation. Transarterial chemoembolization and radiofrequency ablation are the most commonly used method for locoregional therapy. The data associated with newer modalities including drug-eluting beads, radioembolization with Y90, stereotactic radiation therapy and sorafenib will be discussed as a tool for converting advanced HCC to LT candidates. The concept “ablate and wait” has gained the popularity where mandated observation period after neo-adjuvant therapy allows for tumor biology to become apparent, thus has been recommended after down-staging. The role of neo-adjuvant therapy with conjunction of “ablate and wait” in living donor liver transplantation for intermediate stage HCC is also discussed in the paper.

Fujiki, Masato; Aucejo, Federico; Choi, Minsig; Kim, Richard

2014-01-01

341

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.

342

Combination of chemotherapy and photodynamic therapy using graphene oxide as drug delivery system.  

PubMed

Previous research indicated that graphene oxide (GO) can be used to deliver photosensitive anticancer drug, Hypocrellin A (HA), in photodynamic therapy (PDT). However, the anticancer activity of HA was obviously decreased after been loaded on GO. To solve this problem, a chemotherapy drug, 7-ethyl-10-hydroxycamptothecin (SN-38), was co-loaded on the HA loaded GO (HA/SN-38/GO) as a multimodal carrier for the synergistic combination of PDT and chemotherapy for cancer. In vitro results showed that the combination therapy exhibited a synergistic antiproliferative effect compared with PDT and chemotherapy alone. Therefore, HA/SN-38/GO delivery system has the potential to offer dual therapies for the synergistic combination of PDT and chemotherapy for the treatment of cancer. PMID:24792568

Zhou, Lin; Zhou, Lin; Wei, Shaohua; Ge, Xuefeng; Zhou, Jiahong; Jiang, Huijun; Li, Fuyou; Shen, Jian

2014-06-01

343

Synchronous postoperative adjuvant chemoradiation therapy for locally advanced carcinoma of the rectum  

Microsoft Academic Search

Background and aimsThe adjuvant management of locally advanced rectal cancer has been the subject of much debate over the past 10 years. Whilst it is now widely accepted that combined chemoradiation therapy is the treatment of choice for adjuvant therapy following resection of high-risk tumours, there is still no clear answer on the sequencing of the two modalities in the postoperative

Bryan H. Burmeister; David Schache; Elizabeth A. Burmeister; Andrew Bell; Michael G. Poulsen; Euan T. Walpole; John Mackintosh

2004-01-01

344

Feasibility of a randomized trial on adjuvant radio-iodine therapy in differentiated thyroid cancer  

Microsoft Academic Search

BACKGROUND: Justification for adjuvant radio-iodine (I-131) therapy in differentiated thyroid cancer (DTC) is purely based on retrospective data. This is true for ablative therapy and even more so for high-dosage adjuvant schedules. Randomized trials on the latter application are considered impossible due to anticipated formidable sample sizes required in a disease with an overall excellent prognosis like DTC. OBJECTIVE: To

C. Dragoiescu; O. S. Hoekstra; D. J. Kuik; P. T. A. M. Lips; M. A. B. D. Plaizier; P. T. R. Rodrigus; D. A. K. C. J. M. Huijsmans; J. G. Ribot; J. Kuijpens; J. W. W. Coebergh; G. J. J. Teule

2003-01-01

345

Neoadjuvant and adjuvant therapy in the management of locally advanced non-small-cell lung cancer  

Microsoft Academic Search

The role of adjuvant therapy in non-small-cell lung cancer continues to be defined. We review the most recent major reports of adjuvant trials. Three large randomized trials of postoperative chemotherapy and\\/or radiation therapy for stage I and II patients have noted improvement trends in median and long-term survival. Two large preoperative phase II trials for stage III A patients have

Michael T. Jaklitsch; Gary M. Strauss; David J. Sugarbaker

1993-01-01

346

Adjuvant Therapy for Adenocarcinoma of the Pancreas: Analysis of Reported Trials and Recommendations for Future Progress  

Microsoft Academic Search

The delivery of postoperative combined modality adjuvant therapy for completely resected pancreatic cancer was initially shown\\u000a to be beneficial on the basis of a prospective, randomized trial published in 1985. Since then, oncologists have debated whether\\u000a chemotherapy, chemoradiation, or both is optimal adjuvant therapy after pancreatectomy for ductal adenocarcinoma of the pancreas;\\u000a no global consensus has emerged. Unfortunately, despite the

Robert A. Wolff; Gauri R. Varadhachary; Douglas B. Evans

2008-01-01

347

[Adjuvant antihormonal therapy for postmenopausal women with primary operable breast cancer].  

PubMed

Adjuvant hormonal therapy results in substantial improvements in disease-free and overall survival for women with operable breast cancer. Many randomised trials of adjuvant tamoxifen have been published, and an updated overview of their results is presented in this paper. The third-generation aromatase inhibitors have recently been compared with tamoxifen. These studies are also reviewed in this paper. The Danish Breast Cancer Cooperative Group recommends adjuvant hormonal therapy consisting of tamoxifen for 2.5 years followed by the aromatase inhibitor for 2.5 years, or 5 years of the aromatase inhibitor for women with contraindications to tamoxifen. PMID:17274922

Tuxen, Malgorzata K; Nielsen, Dorte L; Lindberg, Henriette; Kamby, Claus

2007-01-22

348

Photodynamic therapy for pancreatic and biliary tract carcinoma  

Microsoft Academic Search

The prognosis of patients with pancreatic and biliary tract cancer treated with conventional therapies such as stent insertion\\u000a or chemotherapy is often poor, and new approaches are urgently needed. Surgery is the only curative treatment but is appropriate\\u000a in less than 20% of cases, and even then it is associated with a 5-yr survival of less than 30% in selected

Lakshmana Ayaru; Stephen G. Bown; Stephen P. Pereira

2005-01-01

349

Permanent Occlusion of Feeding Arteries and Draining Veins in Solid Mouse Tumors by Vascular Targeted Photodynamic Therapy (VTP) with Tookad  

Microsoft Academic Search

BackgroundAntiangiogenic and anti-vascular therapies present intriguing alternatives to cancer therapy. However, despite promising preclinical results and significant delays in tumor progression, none have demonstrated long-term curative features to date. Here, we show that a single treatment session of Tookad-based vascular targeted photodynamic therapy (VTP) promotes permanent arrest of tumor blood supply by rapid occlusion of the tumor feeding arteries (FA)

Noa Madar-Balakirski; Catherine Tempel-Brami; Vyacheslav Kalchenko; Ori Brenner; David Varon; Avigdor Scherz; Yoram Salomon; Timothy W. Secomb

2010-01-01

350

Tissue uptake study and photodynamic therapy of melanoma-bearing mice with a nontoxic, effective chlorin.  

PubMed

Chlorins have intense red absorptions and high tumor affinities that make them interesting candidates for photodynamic therapy (PDT) of cancer. This paper reports cytotoxicity, phototoxicity, in vitro cellular uptake, and in vivo biodistribution and PDT efficacy of a synthetic chlorin derivative (TCPCSO?H) towards Cloudman melanoma cells (S91). No cytotoxic effects were observed in vitro at concentrations up to 20??m, and no toxicity was observed in vivo in DBA mice with doses up to 2?mg?kg?¹. Pharmacokinetics and biodistribution of TCPCSO?H were evaluated in vivo in DBA mice bearing S91 tumors. TCPCSO?H demonstrated preferential accumulation in S91 mouse melanoma, with tumor-to-normal tissue ratios of 5 and 11 for muscle and skin, respectively, 24?h after intravenous injection of 2?mg?kg?¹. Photodynamic therapy performed under these conditions with 70?mW?cm?² diode laser irradiation at 655?nm for 25?min (total light dose=105?J?cm?²) resulted in scab formation, followed by temporary or permanent (>60 days) tumor remission. According to the Kaplan-Meier analysis, the median survival time of the control group was 9?days, whereas that of the treated group was 38?days. PMID:21732537

D?browski, Janusz M; Krzykawska, Martyna; Arnaut, Luis G; Pereira, Mariette M; Monteiro, Carlos J P; Simões, Sérgio; Urba?ska, Krystyna; Stochel, Gra?yna

2011-09-01

351

Red diode laser for photodynamic therapy: a small animal efficacy study  

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 efficiently couple that power into optical fibers have dictated their use. Dye lasers, metal vapor lasers, or ion gas lasers have been used in the past as the excitation source for PDT, largely because they provided the only available alternatives. These laser systems are very large and complex, and are very expensive to operate. The introduction of high power visible red laser diodes have provided a cost effective alternative to existing lasers for use in PDT. This paper will describe the features of a prototype preclinical red laser diode source for photodynamic therapy, and will present the results of an animal study conducted with this device. The study, using the photosensitizer SnET2, compared the efficacy of PDT performed with the diode laser system with the results obtained from a traditional dye laser system. Future plans for a clinical version of the system will also be discussed.

Lytle, A. Charles; Doiron, Daniel R.; Selman, Steven H.

1994-07-01

352

Meso-tetraphenylporphyrin in liposomes as a suitable photosenzitizer for photodynamic therapy of tumors.  

PubMed

The suitability of a liposomal form of hydrophobic nonsulfonated meso-tetraphenyl porphyrin (TPP) for the photodynamic therapy of tumors was investigated. TPP was solubilized in small unilamellar lipid vesicles prepared by extrusion on a LIPOSOFAST apparatus. These samples were studied by laser-excited time resolved luminescence and triplet-triplet absorption spectroscopy. In this lipid environment TPP was still an efficient singlet oxygen producer, as indicated by the characteristic singlet oxygen phosphorescence at 1270 nm in D2O, when excited with a 28 ns laser pulse at 412 nm. Moreover, unlike with sulfonated TPP (TPPS4), liposomal TPP showed the reduced decay rates of TPP triplet-states with the increasing time of pre-illumination by a Xenon lamp. This was shown in an indirect way, based upon the appearance of a second component of the luminescence decay at 1270 nm in D2O; and by direct TPP triplet state monitoring, detecting triplet-triplet absorption at 440 nm in H2O. The deactivation of higher triplet states was delayed upon pre-illumination. This reflects an irreversible interaction of singlet oxygen with membrane lipids, thus demonstrating the potential of the liposomal form of TPP to efficiently disintegrate tumor cell membranes and to be a suitable preparation for the photodynamic therapy. PMID:10517287

Lovcinský, M; Borecký, J; Kubát, P; Jezek, P

1999-06-01

353

Simultaneous photodynamic and photothermal therapy using photosensitizer-functionalized pd nanosheets by single continuous wave laser.  

PubMed

In this work, we prepared chlorin e6 (Ce6)-functionalized Pd nanosheets (Pd-PEI-Ce6) for the photodynamic and photothermal combined therapy that use a single laser. To fabricate the Pd-PEI-Ce6 nanocomposite, photosensitizer Ce6 were chemically conjugated to polyethylenimine (PEI) and the formed Ce6-PEI conjugates were then anchored onto Pd nanosheets by electrostatic and coordination interaction. The prepared Pd-PEI-Ce6 nanocomposite were about 4.5 nm in size, exhibited broad, and strong absorption from 450 to 800 nm, good singlet oxygen generation capacity and photothermal conversion efficiency, and excellent biocompability. Significantly greater cell killing was observed when HeLa cells incubated with Pd-PEI-Ce6 were irradiated with the 660 nm laser, attributable to both Pd nanosheets-mediated photothermal ablation and the photodynamic destruction effect of photosensitizer Ce6. The double phototherapy effect was also confirmed in vivo. It was found that the Pd-PEI-Ce6 treated tumor-bearing mice displayed the enhanced therapeutic efficiency compared to that of Pd-PEI, or Ce6-treated mice. Our work highlights the promise of using Pd nanosheets for potential multimode cancer therapies. PMID:24801639

Zhao, Zengxia; Shi, Saige; Huang, Yizhuan; Tang, Shaoheng; Chen, Xiaolan

2014-06-11

354

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

NASA Astrophysics Data System (ADS)

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 a convenient interface with the bacterial cell walls. At the same time photodynamic therapy was delivered by administration of Indocyanine Green (ICG), whose spectrum of molecular excitation overlaps the plasmonic oscillations of gold nanorods (~ 800 nm). Therefore irradiation with NIR light from a low power diode laser resulted into simultaneous photothermolysis and generation of reactive oxygen species and cytotoxic byproducts of ICG. We assessed the inhibition of the bacterial colony forming ability under different NIR light exposures, and compared the performance of the combined treatment (gold nanorods plus ICG) with the projected addition of the separate treatments (either gold nanorods or ICG). Our preliminary results may originate from the interplay of synergistic and conflicting interactions, which may include e.g. the enhanced intake of cytotoxic species due to permeabilization of the bacterial cell walls, quenching of ICG and modification of the bleaching of ICG due to the noble metal surface.

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

2011-02-01

355

System for interstitial photodynamic therapy with online dosimetry: first clinical experiences of prostate cancer  

NASA Astrophysics Data System (ADS)

The first results from a clinical study for Temoporfin-mediated photodynamic therapy (PDT) of low-grade (T1c) primary prostate cancer using online dosimetry are presented. Dosimetric feedback in real time was applied, for the first time to our knowledge, in interstitial photodynamic therapy. The dosimetry software IDOSE provided dose plans, including optical fiber positions and light doses based on 3-D tissue models generated from ultrasound images. Tissue optical property measurements were obtained using the same fibers used for light delivery. Measurements were taken before, during, and after the treatment session. On the basis of these real-time measured optical properties, the light-dose plan was recalculated. The aim of the treatment was to ablate the entire prostate while minimizing exposure to surrounding organs. The results indicate that online dosimetry based on real-time tissue optical property measurements enabled the light dose to be adapted and optimized. However, histopathological analysis of tissue biopsies taken six months post-PDT treatment showed there were still residual viable cancer cells present in the prostate tissue sections. The authors propose that the incomplete treatment of the prostate tissue could be due to a too low light threshold dose, which was set to 5 J/cm2.

Swartling, Johannes; Axelsson, Johan; Ahlgren, Göran; Kälkner, Karl Mikael; Nilsson, Sten; Svanberg, Sune; Svanberg, Katarina; Andersson-Engels, Stefan

2010-09-01

356

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

357

Integral photodynamic therapy of bladder cancer using 5-ALA and white light  

NASA Astrophysics Data System (ADS)

We report on clinical experiences with photodynamic therapy in patients with recurrent, multifocal superficial transitional cell carcinoma of the urinary bladder. PDT is performed by intravesically applied 5-aminolevulinic acid and a Xe arc lamp as a light source delivering more than 5 Watt white light for activation of 5-ALA induced Protoporphyrin IX. For whole bladder wall irradiation a special irrigation catheter system has been developed. Based on that technology we determined whether this treatment modality was effective in destroying urothelial carcinoma and preventing recurrent disease. The study should help defining the optimal target group of patients and is considered as basis for a long term and multicenter clinical trial. The initial clinical results indicate that white light photodynamic therapy with 5-ALA is an effective organ-preserving procedure for treating multifocal superficial transitional cell carcinoma of the bladder, even in patients with refractory urothelial carcinoma and is effective in selectively destroying flat neoplastic lesions like carcinoma in situ. None of the patients showed phototoxic skin reactions or loss of bladder capacity.

Baumgartner, Reinhold; Waidelich, Raphaela; Beyer, Wolfgang; Stepp, Herbert G.; Knuechel-Clarke, Ruth; Hofstetter, Alfons

2005-04-01

358

Cell-Penetrating Peptide Enhanced Intracellular Raman Imaging and Photodynamic Therapy  

PubMed Central

We present the application of a theranostic system combining Raman imaging and photodynamic therapy (PDT) effect. The theranostic nanoplatform was created by loading the photosensitizer, Protoporphyrin IX, onto a Raman-labeled gold nanostar. A cell-penetrating peptide, TAT, enhanced intracellular accumulation of the nanoparticles in order to improve their delivery and efficacy. The plasmonic gold nanostar platform was designed to increase the Raman signal via the surface-enhanced resonance Raman scattering (SERRS) effect. Theranostic SERS imaging and photodynamic therapy using this construct were demonstrated on BT-549 breast cancer cells. The TAT peptide allowed for effective Raman imaging and photosensitization with the nanoparticle construct after a 1-hour incubation period. In the absence of the TAT peptide, nanoparticle accumulation in the cells was not sufficient to be observed by Raman imaging, or to produce any photosensitization effect after this short incubation period. There was no cytotoxic effect observed after nanoparticle incubation, prior to light-activation of the photosensitizer. This report shows the first application of combined SERS imaging and photosensitization from a theranostic nanoparticle construct.

Fales, Andrew M.; Yuan, Hsiangkuo; Vo-Dinh, Tuan

2013-01-01

359

Comparison of light emitting diodes and semiconductor laser inducing photodynamic therapy of cancer cells in vitro  

NASA Astrophysics Data System (ADS)

The goal of anticancer therapy is achievement of balance between destruction of tumour cells and tissues and conservation of physiological functions of noncancer cells. Photodynamic therapy (PDT) is one of novel alternative treatment modality of malignant neoplasms. This method is based on cytotoxic action of excited sensitizers in the oxygen-rich environment. Sensitizers bound to cells and are excited by light source identical to absorption maximum of sensitizer. Photodynamic reactions lead to production of reactive oxygen species (ROS), which cause necrosis or apoptosis of cancer cells. The objective of our work was to analyse of phototoxicity in the sense of DNA damage in cancer cells after PDT by single cell gell electrophoresis (SCGE, comet assay) using ZnTPPS4 (zinc(II)-5,10,15,20-tetrakis(4-sulphonatophenyl) porphyrine and disulfonated chloraluminium phthalocyanine ClAlPcS2 as sensitizers. Violet light emitting diodes (LEDs; 1.5 mJ.cm-2.s-1; 418 nm) and semiconductor laser (50mW; 675 nm) were used as sources of radiation. Level of DNA fragmentation was detected after application of different light doses.

Macecek, Jaroslav; Kolarova, Hana; Bajgar, Robert; Strnad, Miroslav

2007-03-01

360

Quantitative approach to skin field cancerization using a nanoencapsulated photodynamic therapy agent: a pilot study  

PubMed Central

Background This paper introduces a new nanoformulation of 5-aminolevulinic acid (nano-ALA) as well as a novel quantitative approach towards evaluating field cancerization for actinic keratosis and/or skin photodamage. In this pilot study, we evaluated field cancerization using nano-ALA and methyl aminolevulinate (MAL), the latter being commercialized as Metvix®. Methods and results Photodynamic therapy was used for the treatment of patients with selected skin lesions, whereas the fluorescence of the corresponding photosensitizer was used to evaluate the time evolution of field cancerization in a quantitative way. Field cancerization was quantified using newly developed color image segmentation software. Using photodynamic therapy as the precancer skin treatment and the approach introduced herein for evaluation of fluorescent area, we found that the half-life of field cancerization reduction was 43.3 days and 34.3 days for nano-ALA and MAL, respectively. We also found that nano-ALA targeted about 45% more skin lesion areas than MAL. Further, we found the mean reduction in area of skin field cancerization was about 10% greater for nano-ALA than for MAL. Conclusion Although preliminary, our findings indicate that the efficacy of nano-ALA in treating skin field cancerization is higher than that of MAL.

Passos, Simone K; de Souza, Paulo EN; Soares, Priscila KP; Eid, Danglades RM; Primo, Fernando L; Tedesco, Antonio Claudio; Lacava, Zulmira GM; Morais, Paulo C

2013-01-01

361

Characterization of antimicrobial photodynamic therapy-treated Streptococci mutans: an atomic force microscopy study.  

PubMed

Abstract Objective: The aim of the present study was to examine the size and shape of Streptococcus mutans bacterial cells of infected dentin substrate subjected to photodynamic therapy (PDT) using atomic force microscopy (AFM). Background data: New trends in the application of AFM have been developed in the field of dentistry, making AFM a useful technique in high resolution imaging of biological structures and processes. Materials and methods: PDT was completed using an efficient light-emitting diode source (LED - ?=620-660?nm) with total light dose of 94?J/cm(2) in the presence of the photosensitizer toluidine blue O (TBO). Dentin specimens were immersed in brain heart infusion (BHI) broth inoculated with S. mutans for 5 days to induce caries in vitro. After demineralization, the samples were subjected to a series of treatments in which carious dentin infected by S. mutans was exposed to 0.9% sodium chlorite (NaCl) solution (control) for 10?min, or subjected to PDT-TBO photosensitizer followed by light exposure (energy density of 94?J/cm(2)). Results: Three-dimensional (3-D) images and cross-sectional measurements showed rod and diplococcic cell shapes. Photoinactivated bacterial cells did not differ from the control with respect to their cross-sectional shape, but they did show a reduction in size. Conclusions: Photodynamic therapy decreased the diameter of S. mutans cells and AFM may be used as a technique for bacterial cell analysis. PMID:23421628

de Melo, Mary Anne Sampaio; Rolim, Juliana Paiva Marques Lima; Zanin, Iriana Carla Junqueira; Barros, Eduardo Bede; da-Costa, Erivelton Façanha; Rodrigues, Lidiany Karla Azevedo

2013-03-01

362

Release of regulators of angiogenesis following Hypocrellin-A and B photodynamic therapy of human brain tumor cells  

Microsoft Academic Search

Photodynamic therapy (PDT) is an innovative strategy for the treatment of solid neoplasms of the brain. Aside from inducing cell death in tumor cells, PDT induces endothelial cell death and promotes formation of blood clots; however, exact mechanisms that trigger these phenomena remain largely unknown. We now used Western blotting to analyze secretion of regulators of angiogenesis to the supernatants

Martin H Deininger; Toni Weinschenk; Matthias H Morgalla; Richard Meyermann; Hermann J Schluesener

2002-01-01

363

Celecoxib and NS398 Enhance Photodynamic Therapy by Increasing In vitro Apoptosis and Decreasing In vivo Inflammatory and Angiogenic Factors  

Microsoft Academic Search

Photodynamic therapy (PDT) elicits both apoptotic and necrotic responses within treated tumors and produces microvascular injury leading to inflammation and hypoxia. PDT also induces expression of angiogenic and survival molecules including vascular endothelial growth factor, cyclooxygenase-2 (COX-2), and matrix metalloproteinases. Adjunctive administration of inhibitors to these molecules improves PDT responsiveness. In the current study, we examined how the combination of

Angela Ferrario; Anita M. Fisher; Natalie Rucker; Charles J. Gomer

2005-01-01

364

Treatment of Mestastatic Breast Cancer by Photodynamic Therapy Induced Anti-Tumor Immunity in a Murine Model.  

National Technical Information Service (NTIS)

One in 8 women in the United States will develop breast cancer during her lifetime. Deaths are due to tumors that have metastasized. Photodynamic therapy (PDT) is a promising cancer treatment in which a photosensitizer (PS) accumulates in tumors and is su...

A. P. Castano

2005-01-01

365

Development of an alternative light source to lasers for photodynamic therapy: 2. Comparative in vivo tumour response characteristics  

Microsoft Academic Search

The performance of a low cost, table-top\\/portable light source was tested against an argon ion pumped dye laser for in vivo photodynamic therapy (PDT). The prototype delivers up to 1 W via a 4 mm flexible lightguide within a 30 nm bandwidth centred at any wavelength from 300 nm to 1200 nm at fluence rates of up to 8 W

C. Whitehurst; J. D. Humphries; J. V. Moore

1995-01-01

366

Reduction in the response to coronary and iliac artery injury with photodynamic therapy using 5-aminolaevulinic acid  

Microsoft Academic Search

Objective: Photodynamic therapy (PDT) uses red light (non-thermal, non-ionising) to activate a previously administered photosensitis- ing drug. This inhibits neointimal hyperplasia in injured arteries in small animals where it appears safe and well tolerated. Our aim was to develop a method for percutaneous application of PDT to iliac and coronary arteries in a large animal model and investigate its influence

Michael P. Jenkins; Giovanni A. Buonaccorsi; Richard Mansfield; Christopher C. R. Bishop; Stephen G. Bown; Jean R. McEwan

367

Efficiency of photodynamic therapy in the treatment of diffuse facial viral warts in an immunosuppressed patient: towards a gold standard?  

PubMed

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. PMID:21537372

Caucanas, M; Gillard, P; Vanhooteghem, O

2010-01-01

368

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

369

Retrospective Review of Eyes with Neovascular Age-related Macular Degeneration Treated with Photodynamic Therapy with Verteporfin and Intravitreal Triamcinolone  

Microsoft Academic Search

Aim: To review the outcomes of eyes with neovascular age-related macular degeneration (AMD) treated with photodynamic therapy (PDT) with verteporfin and intravitreal triamcino- lone acetonide injection. Materials and Methods: We retrospectively reviewed the outcomes of consecutive eyes with neovascular AMD that received an intravitreal triamcinolone injection within 1 week of their first PDT and had at least 6 months of

Tamara K Fackler; Shantan Reddy; Srilaxmi Bearelly; Sandra Stinnett; Sharon Fekrat; Michael J Cooney

370

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

371

Mechanisms in photodynamic therapy: part two--cellular signaling, cell metabolism and modes of cell death  

PubMed Central

Summary Photodynamic therapy (PDT) has been known for over a hundred years, but is only now becoming widely used. Originally developed as a tumor therapy, some of its most successful applications are for non-malignant disease. In the second of a series of three reviews, we will discuss the mechanisms that operate in PDT on a cellular level. In Part I [Castano AP, Demidova TN, Hamblin MR. Mechanism in photodynamic therapy: part one—photosensitizers, photochemistry and cellular localization. Photodiagn Photodyn Ther 2004;1:279–93] it was shown that one of the most important factors governing the outcome of PDT, is how the photosensitizer (PS) interacts with cells in the target tissue or tumor, and the key aspect of this interaction is the subcellular localization of the PS. PS can localize in mitochondria, lysosomes, endoplasmic reticulum, Golgi apparatus and plasma membranes. An explosion of investigation and explorations in the field of cell biology have elucidated many of the pathways that mammalian cells undergo when PS are delivered in tissue culture and subsequently illuminated. There is an acute stress response leading to changes in calcium and lipid metabolism and production of cytokines and stress proteins. Enzymes particularly, protein kinases, are activated and transcription factors are expressed. Many of the cellular responses are centered on mitochondria. These effects frequently lead to induction of apoptosis either by the mitochondrial pathway involving caspases and release of cytochrome c, or by pathways involving ceramide or death receptors. However, under certain circumstances cells subjected to PDT die by necrosis. Although there have been many reports of DNA damage caused by PDT, this is not thought to be an important cell-death pathway. This mechanistic research is expected to lead to optimization of PDT as a tumor treatment, and to rational selection of combination therapies that include PDT as a component.

Castano, Ana P.; Demidova, Tatiana N.; Hamblin, Michael R.

2013-01-01

372

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

373

Adjuvant Medical Therapy for HER2-Positive Breast Cancer  

MedlinePLUS

... based validation of the prognostic model ADJUVANT! for early breast cancer. J Clin Oncol 2005; 23:2716. Harris L, Fritsche H, Mennel R, et al. American Society of Clinical Oncology 2007 update of recommendations for the use ...

374

Quality of Life Issues During Adjuvant Endocrine Therapy  

Microsoft Academic Search

When the media report the results from studies reporting the latest breakthrough in adjuvant drug treatments, they are usually\\u000a described in terms of relative rather than absolute benefits. Many women with early stage breast (EBC) cancer may not realise\\u000a that they do not necessarily require any further adjuvant treatments and that claims for example of a 50% reduction in risk

Lesley Fallowfield; Valerie Jenkins

375

Adjuvant therapy for colon cancer based on pharmacogenomics?  

Microsoft Academic Search

The impact of adjuvant chemotherapy for patients with localized colon adenocarcinoma is obvious for stage III and high-risk\\u000a stage II patients but remains somewhat controversial for low-risk stage II. Until now, the decision of an adjuvant chemotherapy\\u000a is based on pathologic and clinical data. However, some important questions remain. In stage III, how can we improve the results?\\u000a In low-risk

Erick Gamelin; Michele Boisdron-Celle; Alain Morel; Olivier Capitain; Olivier Coqueret

2007-01-01

376

Adrenocortical carcinoma: is adjuvant therapy indicated? A single institution experience  

Microsoft Academic Search

Background. Adrenocortical carcinomas are rare tumors with an aggressive natural history. Complete surgical resection of the tumor is\\u000a possible only in few patients, and even after complete resection many patients develop local recurrence of tumor or distant\\u000a metastases. The role of adjuvant chemotherapy is not established, and there are no published series on the probable benefit\\u000a of adjuvant cisplatin-based chemotherapy.

Rojymon Jacob; Jayaprakash Madhavan; Rema Jyothirmayi; Madhavan Krishnan Nair

2000-01-01

377

Studies on Preparation of Photosensitizer Loaded Magnetic Silica Nanoparticles and Their Anti-Tumor Effects for Targeting Photodynamic Therapy.  

PubMed

As a fast developing alternative of traditional therapeutics, photodynamic therapy (PDT) is an effective, noninvasive, nontoxic therapeutics for cancer, senile macular degeneration, and so on. But the efficacy of PDT was compromised by insufficient selectivity and low solubility. In this study, novel multifunctional silica-based magnetic nanoparticles (SMNPs) were strategically designed and prepared as targeting drug delivery system to achieve higher specificity and better solubility. 2,7,12,18-Tetramethyl-3,8-di-(1-propoxyethyl)-13,17-bis-(3-hydroxypropyl) porphyrin, shorted as PHPP, was used as photosensitizer, which was first synthesized by our lab with good PDT effects. Magnetite nanoparticles (Fe(3)O(4)) and PHPP were incorporated into silica nanoparticles by microemulsion and sol-gel methods. The prepared nanoparticles were characterized by transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and fluorescence spectroscopy. The nanoparticles were approximately spherical with 20-30 nm diameter. Intense fluorescence of PHPP was monitored in the cytoplasm of SW480 cells. The nanoparticles possessed good biocompatibility and could generate singlet oxygen to cause remarkable photodynamic anti-tumor effects. These suggested that PHPP-SMNPs had great potential as effective drug delivery system in targeting photodynamic therapy, diagnostic magnetic resonance imaging and magnetic hyperthermia therapy. GRAPHICAL ABSTRACT: Novel multifunctional photosensitizer loaded magnetic silica nanoparticles were strategically prepared with low toxicity, good biocompatibility and remarkable photodynamic anti-tumor efficacy. The nanoparticles were believed to be of great value as drug delivery system in targeting photodynamic therapy, diagnostic magnetic resonance imaging and magnetic hyperthermia therapy. PMID:20596490

Chen, Zhi-Long; Sun, Yun; Huang, Peng; Yang, Xiao-Xia; Zhou, Xing-Ping

2009-01-01

378

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

379

Pheophorbide a mediated photodynamic therapy against human epidermoid carcinoma cells (A431)  

NASA Astrophysics Data System (ADS)

The objective of this study was to characterize the death mechanism of human epidermoid carcinoma cells (A431) triggered by photodynamic therapy (PDT) with pheophorbide a. First of all, significant inhibition on the survival of A431 cells (< 20 %) was observed when an irradiation dose of 5.1 J/cm2 combined with 125 ng/ml of pheophorbide a was applied. Survival rate of human keratinocyte cells was over 70 % under the same PDT parameters, suggesting that pheophorbide a killed cancer cells selectively. Mitochondria were the main target sites where pheophorbide a accumulated. Formation of reactive oxygen species (ROS) was detected after PDT. Addition of antioxidant N-Acetyl cysteine prevented ROS production and increased cell survival thereafter. The decrease in cellular ATP level was also observed at 6 hrs after PDT. Typical apoptotic cellular morphology and a collapse of mitochondrial membrane potential occurred after PDT. The loss of mitochondrial membrane potential led to the release of cytochrome c from the mitochondria to the cytosol, followed by activation of caspase-9 and caspase-3. The activation of caspase-3 resulted in poly(ADP-ribose) polymerase (PARP) cleavage in A431 cells, followed by DNA fragmentation. In conclusion, the results demonstrated that pheophorbide a possessed photodynamic action against A431 cells, mainly through apoptosis mediated by mitochondrial intrinsic pathway triggered by ROS.

Chen, Yi-Chun; Li, Wen-Tyng

2011-02-01

380

Two combined photosensitizers: a goal for more effective photodynamic therapy of cancer  

PubMed Central

Photodynamic therapy (PDT) is a clinically approved therapeutic modality for the treatment of diseases characterized by uncontrolled cell proliferation, mainly cancer. It involves the selective uptake of a photosensitizer (PS) by neoplastic tissue, which is able to produce reactive oxygen species upon irradiation with light, leading to tumor regression. Here a synergistic cell photoinactivation is reported based on the simultaneous administration of two PSs, zinc(II)-phthalocyanine (ZnPc) and the cationic porphyrin meso-tetrakis(4-N-methylpyridyl)porphine (TMPyP) in three cell lines (HeLa, HaCaT and MCF-7), using very low doses of PDT. We detected changes from predominant apoptosis (without cell detachment) to predominant necrosis, depending on the light dose used (2.4 and 3.6?J/cm2, respectively). Analysis of changes in cytoskeleton components (microtubules and F-actin), FAK protein, as well as time-lapse video microscopy evidenced that HeLa cells were induced to undergo apoptosis, without losing adhesion to the substrate. Moreover, 24?h after intravenous injection into tumor-bearing mice, ZnPc and TMPyP were preferentially accumulated in the tumor area. PDT with combined treatment produced significant retardation of tumor growth. We believe that this combined and highly efficient strategy (two PSs) may provide synergistic curative rates regarding conventional photodynamic treatments (with one PS alone).

Acedo, P; Stockert, J C; Canete, M; Villanueva, A

2014-01-01

381

Necrosis response to photodynamic therapy using light pulses in the femtosecond regime.  

PubMed

One of the clinical limitations of the photodynamic therapy (PDT) is the reduced light penetration into biological tissues. Pulsed lasers may present advantages concerning photodynamic response when compared to continuous wave (CW) lasers operating under the same average power conditions. The aim of this study was to investigate PDT-induced response when using femtosecond laser (FSL) and a first-generation photosensitizer (Photogem) to evaluate the induced depth of necrosis. The in vitro photodegradation of the sensitizer was monitored during illumination either with CW or an FSL as an indirect measurement of the PDT response. Healthy liver of Wistar rats was used to evaluate the tissue response. The photosensitizer was endovenously injected and 30 min after, an energy dose of 150 J?cm(-2) was delivered to the liver surface. We observed that the photodegradation rate evaluated via fluorescence spectroscopy was higher for the FSL illumination. The FSL-PDT produced a necrosis nearly twice as deep when compared to the CW-PDT. An increase of the tissue temperature during the application was measured and was not higher than 2.5 °C for the CW laser and not higher than 4.5 °C for the pulsed laser. FSL should be considered as an alternative in PDT applications for improving the results in the treatment of bulky tumors where higher light penetration is required. PMID:23064891

Grecco, Clóvis; Moriyama, Lilian Tan; Cosci, Alessandro; Pratavieira, Sebastião; Bagnato, Vanderlei Salvador; Kurachi, Cristina

2013-07-01

382

Effect of 1O2 quencher depletion on the efficiency of photodynamic therapy.  

PubMed

Al(III) phthalocyanine chloride tetrasulfonic acid (AlPcS4) fluorescence and photodynamic oxygen consumption were monitored during AlPcS4-photodynamic therapy (PDT) of Mat LyLu cells in suspension. These measurements were used to calculate the PDT efficiency, which is defined as the oxygen consumption rate divided by the sensitizer concentration. As a function of the intracellular oxygen concentration consumed by PDT, the normalized PDT efficiency fell off more quickly at lower photosensitizer concentrations. The changes in PDT efficiency were compared to models of PDT in which the photosensitizer (PS) and singlet oxygen quencher (A) were either free to diffuse or were fixed. The model in which PS and A are free to diffuse did not agree with the experimental data because this model predicts that the reduction in PDT efficiency is independent of [PS]. A Monte Carlo model was written to simulate PDT when both PS and A are stationary. This model was found to describe the experimental data when the initial intracellular [A] = 90 mM and when the initial and final (i.e. after all A has been depleted) singlet oxygen lifetimes were 0.4 and 1.2 ?s respectively. PMID:24296529

Weston, Mark A; Patterson, Michael S

2014-01-01

383

Two combined photosensitizers: a goal for more effective photodynamic therapy of cancer.  

PubMed

Photodynamic therapy (PDT) is a clinically approved therapeutic modality for the treatment of diseases characterized by uncontrolled cell proliferation, mainly cancer. It involves the selective uptake of a photosensitizer (PS) by neoplastic tissue, which is able to produce reactive oxygen species upon irradiation with light, leading to tumor regression. Here a synergistic cell photoinactivation is reported based on the simultaneous administration of two PSs, zinc(II)-phthalocyanine (ZnPc) and the cationic porphyrin meso-tetrakis(4-N-methylpyridyl)porphine (TMPyP) in three cell lines (HeLa, HaCaT and MCF-7), using very low doses of PDT. We detected changes from predominant apoptosis (without cell detachment) to predominant necrosis, depending on the light dose used (2.4 and 3.6?J/cm(2), respectively). Analysis of changes in cytoskeleton components (microtubules and F-actin), FAK protein, as well as time-lapse video microscopy evidenced that HeLa cells were induced to undergo apoptosis, without losing adhesion to the substrate. Moreover, 24?h after intravenous injection into tumor-bearing mice, ZnPc and TMPyP were preferentially accumulated in the tumor area. PDT with combined treatment produced significant retardation of tumor growth. We believe that this combined and highly efficient strategy (two PSs) may provide synergistic curative rates regarding conventional photodynamic treatments (with one PS alone). PMID:24625981

Acedo, P; Stockert, J C; Cañete, M; Villanueva, A

2014-01-01

384

Monte Carlo simulations for optimal light delivery in photodynamic therapy of non-melanoma skin cancer  

NASA Astrophysics Data System (ADS)

The choice of light source is important for the efficacy of photodynamic therapy (PDT) of non-melanoma skin cancer. We simulated the photodynamic dose (PDD) delivered to a tumour during PDT using theoretical radiation transfer simulations performed via our 3D Monte Carlo radiation transfer (MCRT) model for a range of light sources with light doses up to 75 J cm-2. The PDD delivered following superficial irradiation from (A) non-laser light sources, (B) monochromatic light, (C) alternate beam diameters and (D) re-positioning of the tumour within the tissue was computed. (A) The final PDD deposited to the tumour at a depth of 2 mm by the Paterson light source was 2.75, 2.50 and 1.04 times greater than the Waldmann 1200, Photocure and Aktilite, respectively. (B) Tumour necrosis occurred at a depth of 2.23 mm and increased to 3.81 mm for wavelengths 405 and 630 nm, respectively. (C) Increasing the beam diameter from 10 to 50 mm had very little effect on depth of necrosis. (D) As expected, necrosis depths were reduced when the tumour was re-positioned deeper into the tissue. These MCRT simulations show clearly the importance of choosing the correct light source to ensure optimal light delivery to achieve tumour necrosis.

Valentine, R. M.; Wood, K.; Brown, C. T. A.; Ibbotson, S. H.; Moseley, H.

2012-10-01

385

Monte Carlo simulations for optimal light delivery in photodynamic therapy of non-melanoma skin cancer.  

PubMed

The choice of light source is important for the efficacy of photodynamic therapy (PDT) of non-melanoma skin cancer. We simulated the photodynamic dose (PDD) delivered to a tumour during PDT using theoretical radiation transfer simulations performed via our 3D Monte Carlo radiation transfer (MCRT) model for a range of light sources with light doses up to 75 J cm(-2). The PDD delivered following superficial irradiation from (A) non-laser light sources, (B) monochromatic light, (C) alternate beam diameters and (D) re-positioning of the tumour within the tissue was computed. (A) The final PDD deposited to the tumour at a depth of 2 mm by the Paterson light source was 2.75, 2.50 and 1.04 times greater than the Waldmann 1200, Photocure and Aktilite, respectively. (B) Tumour necrosis occurred at a depth of 2.23 mm and increased to 3.81 mm for wavelengths 405 and 630 nm, respectively. (C) Increasing the beam diameter from 10 to 50 mm had very little effect on depth of necrosis. (D) As expected, necrosis depths were reduced when the tumour was re-positioned deeper into the tissue. These MCRT simulations show clearly the importance of choosing the correct light source to ensure optimal light delivery to achieve tumour necrosis. PMID:22990348

Valentine, R M; Wood, K; Brown, C T A; Ibbotson, S H; Moseley, H

2012-10-21

386

Photodynamic therapy based on 5-aminolevulinic acid and its use as an antimicrobial agent.  

PubMed

Exogenous 5-aminolevulinic acid (ALA) is taken up directly by bacteria, yeasts, fungi, and some parasites, which then induces the accumulation of protoporphyrin IX (PPIX). Subsequent light irradiation of PPIX leads to the inactivation of these organisms via photodamage to their cellular structures. ALA uptake and light irradiation of PPIX produced by host cells leads to the inactivation of other parasites, along with some viruses, via the induction of an immune response. ALA-mediated PPIX production by host cells and light irradiation result in the inactivation of other viruses via either the induction of a host cell response or direct photodynamic attack on viral particles. This ALA-mediated production of light-activated PPIX has been extensively used as a form of photodynamic therapy (PDT) and has shown varying levels of efficacy in treating conditions that are associated with microbial infection, ranging from acne and verrucae to leishmaniasis and onychomycosis. However, for the treatment of some of these conditions by ALA-based PDT, the role of an antimicrobial effect has been disputed and in general, the mechanisms by which the technique inactivates microbes are not well understood. In this study, we review current understanding of the antimicrobial mechanisms used by ALA-based PDT and its role in the treatment of microbial infections along with its potential medical and nonmedical applications. PMID:21793017

Harris, Frederick; Pierpoint, Lynne

2012-11-01

387

The neovessel occlusion efficacy of 15-hydroxypurpurin-7-lactone dimethyl ester induced with photodynamic therapy.  

PubMed

In this study, the photodynamic therapy (PDT) induced efficacy of a semi-synthesized analogue 15(1)-hydroxypurpurin-7-lactone dimethyl ester or G2, in terms of chick chorioallantoic membrane blood vessel occlusion was evaluated in reference to verteporfin. Early formulation studies showed that G2 prepared in a system of cremophor EL 2.5% and ethanol 2.5% in saline was biocompatible up to 20 microL volume of injection. Following injection, G2 accumulation peaked within the first minute and its extravasation from intra- to extra-vascular occurred somewhat slower as compared with verteporfin. In the PDT study, closure of capillaries and small neovessels was observed with 4 microg per embryo of G2 and a light dose of 20 J cm(-2) at a fluence rate of 40 mW cm(-2) filtered at 400-440 nm-a result that may be considered optimum for the treatment of age-related macular degeneration (AMD). Also, partial occlusion of the large vessels was observed using the same dose of G2 and light-an effect which is desirable for cancer treatment. From this study, we conclude that G2 has the potential to be developed as a therapeutic agent for photodynamic treatment for AMD and cancer. PMID:20074086

Lim, Siang Hui; Nowak-Sliwinska, Patrycja; Kamarulzaman, Fadzly Adzhar; van den Bergh, Hubert; Wagnières, Georges; Lee, Hong Boon

2010-01-01

388

Protein modified upconversion nanoparticles for imaging-guided combined photothermal and photodynamic therapy.  

PubMed

In this work, we develop a multifunctional nano-platform by coating upconversion nanoparticles (UCNPs) with bovine serum albumin (BSA), obtaining UCNP@BSA nanoparticles with great solubility and stability in physiological environments. Two types of dye molecules, including a photosensitizer, Rose Bengal (RB), and an NIR-absorbing dye, IR825, can be simultaneously loaded into the BSA layer of the UCNP@BSA nanoparticles. In this carefully designed UCNP@BSA-RB&; IR825 system, RB absorbs green light emitted from UCNPs under 980-nm excitation to induce photodynamic cancer cell killing, while IR825 whose absorbance shows no overlap with upconversion excitation and emission wavelengths, offers nanoparticles a strong photothermal perform under 808-nm laser irradiation. Without showing noticeable dark toxicity, the obtained dual-dye loaded nanoparticles are able to kill cancer via combined photothermal and photodynamic therapies, both of which are induced by NIR light with high tissue penetration, by a synergetic manner both in vitro and in vivo. In addition, the intrinsic paramagnetic and optical properties of Gd(3+)-doped UCNPs can further be utilized for in vivo dual modal imaging. Our study suggests that UCNPs with well-designed surface engineering could serve as a multifunctional nano-platform promising in cancer theranostics. PMID:24412081

Chen, Qian; Wang, Chao; Cheng, Liang; He, Weiwei; Cheng, Zhengping; Liu, Zhuang

2014-03-01

389

Lipid coated upconverting nanoparticles as NIR remote controlled transducer for simultaneous photodynamic therapy and cell imaging.  

PubMed

The application of photodynamic therapy in deep tissue is constrained by some pending problems, such as the limited penetration depth of excitation light and lacking of targeting ability. In this paper, a new kind of lipid coated upconverting nanoparticles consisiting of upconerting nanocrystal core and targeted lipid polymer shell was first reported for NIR triggered photodynamic therapy and cell imaging simultaneously. The lipid coated upconverting nanoparticles offers advantages to overcome the problem mentioned above. The UCN core works as a transducer to convert deeply penetrating near-infrared light to visible lights for activating photosensitizer and cell fluorescence imaging simultaneously. The amphiphilic lipid polymer RGD peptide conjugated poly (maleic anhydride-alt-1-octadecene) grafted dioleoyl l-?-phosphatidylethanolamine (RGD-PMAO-DOPE) acts as a shield. It can protect the system from catching by RES and target the whole system to the lesions. The experiment results show that the lipid coated upconverting nanoparticle is individual nanosphere with an average size of 20 nm. The drug loading can reach 9%. After NIR exposed, the MC540 was activated to produce singlet oxygen (ROS) successfully by the upconverting fluorescence emitted from UCN. Importantly, compared with nanoparticle without RGD decoration, the lipid coated upconverting nanoparticle can co-deliver the MC540 and UCNs into the same cell with higher efficiency. Besides, the MC540 loaded UCN/RGD-PMAO-DOPE nanoparticles showed significant inhibitory effect on tumor cells after NIR shining. Our data suggests that MC540 loaded UCN/RGD-PMAO-DOPE nanoparticle may be a useful nanoplatform for future PDT treatment in deep-cancer therapy. PMID:24657139

Wang, Hanjie; Dong, Chunhong; Zhao, Peiqi; Wang, Sheng; Liu, Zhongyun; Chang, Jin

2014-05-15

390

Comparison of photodynamic therapy with different excitation wavelengths using a dynamic model of aminolevulinic acid-photodynamic therapy of human skin  

NASA Astrophysics Data System (ADS)

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.

Liu, Baochang; Farrell, Thomas J.; Patterson, Michael S.

2012-08-01

391

Long-Term Outcome of Photodynamic Therapy with Systemic Chemotherapy Compared to Photodynamic Therapy Alone in Patients with Advanced Hilar Cholangiocarcinoma  

PubMed Central

Background/Aims Patients with cholangiocarcinoma usually present at an advanced stage, and more than 50% of cases are not resectable at the time of diagnosis. Recently, photodynamic therapy (PDT) has been proposed as a palliative and neoadjuvant modality. We evaluated whether combination of PDT and chemotherapy is more effective than PDT alone. Methods In total, 161 patients with cholangiocarcinoma diagnosed between February 1999 and September 2009 were evaluated. Sixteen patients were treated with PDT and chemotherapy (group A), and 58 were treated with PDT (group B). Results The median survival was 538 days (95% confidence interval [CI], 475.3 to 600.7) in group A and 334 days (95% CI, 252.5 to 415.5) in group B (p=0.05). Lymph node metastasis status, serum bilirubin of pretreatment, tumor node metastasis stage, treatment method (PDT with chemotherapy vs PDT alone), time to PDT and the number of PDT sessions were prognostic factors with statistical significance in the univariate analysis. A multivariate analysis showed that PDT with chemotherapy and more than two sessions of PDT were significant independent predictors of longer survival in advanced cholangiocarcinoma (hazard ratio [HR], 2.23; 95% CI, 1.18 to 4.20; p=0.013 vs HR, 1.79; 95% CI, 1.044 to 3.083; p=0.034). Conclusions PDT with chemotherapy results in longer survival than PDT alone.

Hong, Mi Jin; Lee, Eung Jun; Lee, Tae Yoon; Shim, Chan Sup

2014-01-01

392

Chronic myelogenous leukemia after postoperative adjuvant S-1 therapy for rectal cancer: a case report  

PubMed Central

We report a case in which chronic myelogenous leukemia (CML) developed after postoperative adjuvant S-1 therapy for rectal cancer. A 56-year-old man was diagnosed with rectal adenocarcinoma, which was treated with abdominoperineal resection followed by a year of adjuvant S-1 therapy. At 39 postoperative months, he was diagnosed with CML. Although it remains unclear that CML that develops after treatment involving cytotoxic agents is treatment-related, clinicians should be aware of the possibility of CML developing after S-1 therapy.

Manabe, Masahiro; Nishii, Takafumi; Okita, Junya; Nagasaki, Johji; Harada, Naonori; Aoyama, Yasutaka; Kumura, Takeo; Ohta, Tadanobu; Furukawa, Yoshio; Takeuchi, Kazuhiro; Mugitani, Atsuko

2013-01-01

393

Antimicrobial Effects of Photodynamic Therapy on Patients with Necrotic Pulps and Periapical Lesion  

PubMed Central

This study analyzed the antimicrobial effect of photodynamic therapy (PDT) in association with endodontic treatment. Twenty patients were selected. Microbiological samples were taken after accessing the canal, endodontic therapy, and PDT. At the end of the first session, the root canal was filled with Ca(OH)2, and after 1 week, a second session of the therapies was performed. Endodontic therapy gave a mean reduction of 1.08 log. The combination with PDT significantly enhanced the reduction (1.83 log, p = 0.00002). The second endodontic session gave a similar diminution to the first (1.14 log), and the second PDT was significantly more effective than the first (p = 0.002). The second total reduction was significantly higher than the second endodontic therapy (p = 0.0000005). The total first + second reduction (3.19 log) was significantly different from the first combination (p = 0.00006). Results suggest that the use of PDT added to endodontic treatment leads to an enhanced decrease of bacterial load and may be an appropriate approach for the treatment of oral infections.

Garcez, Aguinaldo Silva; Nunez, Silvia Cristina; Hamblin, Michael R.; Ribeiro, Martha Simoes

2010-01-01

394

Adjuvant electrochemotherapy in veterinary patients: a model for the planning of future therapies in humans  

Microsoft Academic Search

The treatment of soft tissue tumors needs the coordinated adoption of surgery with radiation therapy and eventually, chemotherapy. The radiation therapy (delivered with a linear accelerator) can be preoperative, intraoperative, or postoperative. In selected patients adjuvant brachytherapy can be adopted. The goal of these associations is to achieve tumor control while maximally preserving the normal tissues from side effects. Unfortunately,

Enrico P Spugnini; Gennaro Citro; Alfonso Baldi

2009-01-01

395

Neoadjuvant or adjuvant therapy for resectable esophageal cancer: a clinical practice guideline  

Microsoft Academic Search

BACKGROUND: Carcinoma of the esophagus is an aggressive malignancy with an increasing incidence. Its virulence, in terms of symptoms and mortality, justifies a continued search for optimal therapy. A clinical practice guideline was developed based on a systematic review investigating neoadjuvant or adjuvant therapy on resectable thoracic esophageal cancer. METHODS: A systematic review with meta-analysis was developed and clinical recommendations

Richard A Malthaner; Rebecca KS Wong; R Bryan Rumble; Lisa Zuraw

2004-01-01

396

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

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 Central

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. Table 1. Immunohistochemistry staining pattern Abbreviations: CA, cancer antigen; CK, cytokeratin; ER, estrogen receptor; GCDFP, gross cystic disease fluid protein; PAX, paired box; PR, progesterone receptor; TTF, thyroid transcription factor; WT, Wilms' tumor.

Zhu, Andrew X.; Knox, Jennifer J.

2012-01-01

399

The application of hyaluronic acid-derivatized carbon nanotubes in hematoporphyrin monomethyl ether-based photodynamic therapy for in vivo and in vitro cancer treatment  

PubMed Central

Carbon nanotubes (CNTs) have shown great potential in both photothermal therapy and drug delivery. In this study, a CNT derivative, hyaluronic acid-derivatized CNTs (HA-CNTs) with high aqueous solubility, neutral pH, and tumor-targeting activity, were synthesized and characterized, and then a new photodynamic therapy agent, hematoporphyrin monomethyl ether (HMME), was adsorbed onto the functionalized CNTs to develop HMME-HA-CNTs. Tumor growth inhibition was investigated both in vivo and in vitro by a combination of photothermal therapy and photodynamic therapy using HMME-HA-CNTs. The ability of HMME-HA-CNT nanoparticles to combine local specific photodynamic therapy with external near-infrared photothermal therapy significantly improved the therapeutic efficacy of cancer treatment. Compared with photodynamic therapy or photothermal therapy alone, the combined treatment demonstrated a synergistic effect, resulting in higher therapeutic efficacy without obvious toxic effects to normal organs. Overall, it was demonstrated that HMME-HA-CNTs could be successfully applied to photodynamic therapy and photothermal therapy simultaneously in future tumor therapy.

Shi, Jinjin; Ma, Rourou; Wang, Lei; Zhang, Jing; Liu, Ruiyuan; Li, Lulu; Liu, Yan; Hou, Lin; Yu, Xiaoyuan; Gao, Jun; Zhang, Zhenzhong

2013-01-01

400

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

401

Light dosimetry for photodynamic therapy of superficial tumors in the bladder  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) of tumors in the urinary bladder requires a homogeneous light distribution on the whole organ wall. The light applicator recently developed consists of a catheter-supported isotropic emitter and a concentric outer balloon, which guarantees a centric position. For dosimetry a detector fiber with conical end is axially placed half way between center and bladder outlet. It detects the light backscattered from the bladder wall. It has been tested by means of a bladder phantom model with variable backscattering properties. To study the limits of this irradiation and dosimetry concept in case of nonspherical bladder shapes the light distributions in hollow ellipsoids with backscattering surface have been investigated by computer simulation. It shows that the ratio of the largest to the smallest fluence rate and the ratio of the largest to the smallest diameter of the bladder are nearly equal.

Beyer, Wolfgang; Pongratz, T.; Hofstetter, Alfons G.; Jocham, Dieter; Unsoeld, Eberhard

1994-03-01

402

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

403

On the photodynamic therapy action spectrum of zinc phthalocyanine tetrasulphonic acid in vivo.  

PubMed

The photodynamic therapy (PDT) activity of zinc phthalocyanine tetrasulphonic acid in a rodent tumour model was shown to be critically dependent on the wavelength of the excitation laser light over a relatively small wavelength range. Thus the sensitizer showed a doubling of the PDT activity with fibrosarcoma LSBD1 in BDIX rats when the wavelength of the illuminant was displaced from 680 to 692 nm. Under these conditions, the sensitizer is approximately three times more effective than polyhaematoporphyrin, whereas previously it has been considered to be of low PDT activity. This wavelength effect is attributed to a red shift of the absorption spectrum of the sensitizer in cells compared with that in solution. Fluorescence excitation studies with sensitizer absorbed in mouse 3T3 fibroblast cells are consistent with such a red shift. PMID:7646616

Griffiths, J; Cruse-Sawyer, J; Wood, S R; Schofield, J; Brown, S B; Dixon, B

1994-08-01

404

Interstitial photodynamic therapy for cancers of cavum oris, skin, and cervix  

NASA Astrophysics Data System (ADS)

Interstitial photodynamic therapy, in which the straight cut optical fiber was directly inserted into tumors and the insertion points were rationally arranged on an entire lesion area, was performed on 31 oral cancers, 6 skin cancers, and 4 cervix cancers in 41 patients. A highly satisfactory rate of complete response (90%) was obtained via only one treatment. And no severe complication occurred in any of the treatments. The follow-up record for 33 cases with a CR curative effect shows 12 cases have survived free of tumor more than 4 years and only 5 cases relapsed within a year. In this paper, the factors affecting therapeutic effectiveness and the selection of indication are discussed.

Zeng, Chao-Ying; Yang, Dong; Wang, Kaihua; Cao, Qingqing

1993-03-01

405

Photodynamic Therapy for Diffuse Choroidal Hemangioma in Sturge-Weber Syndrome  

PubMed Central

Purpose. To report the treatment outcome of photodynamic therapy with verteporfin (PDT) for exudative retinal detachment (RD) associated with diffuse choroidal hemangioma in Sturge-Weber syndrome (SWS). Methods. An interventional case report of a 10-year-old girl with SWS who developed an exudative RD (visual acuity hand motions) that was treated with PDT. She was treated with a first session of multispot PDT. Posteriorly, a choroidotomy for drainage of subretinal fluid was created, combined with an intravitreal injection of gas (SF6) and cryoapplication. Finally, a second session of PDT was applied. Results. Subretinal fluid resolved over a period of one year and visual acuity increased to 20/125. Conclusions. PDT is an effective therapeutic option for exudative RD associated with diffuse choroidal hemangioma.

Monteiro, Silvia; Casal, Ines; Santos, Marinho

2014-01-01

406

Improved low-power semiconductor diode lasers for photodynamic therapy in veterinary medicine  

NASA Astrophysics Data System (ADS)

Cryogenically cooling semiconductor diode lasers provides higher power output, longer device lifetime, and greater monochromaticity. While these effects are well known, such improvements have not been quantified, and thus cryogenically operated semiconductor lasers have not been utilized in photodynamic therapy (PDT). We report quantification of these results from laser power meter and photospectrometer data. The emission wavelengths of these low power multiple quantum well semiconductor lasers were found to decrease and become more monochromatic with decreasing temperature. Significant power output improvements also were obtained at cryogenic temperatures. In addition, the threshold current, i.e. the current at which lasing begins, decreased with decreasing temperature. This lower threshold current combined with the increased power output produced dramatically higher device efficiencies. It is proposed that cryogenic operation of semiconductor diode lasers will reduce the number of devices needed to produce the requisite output for many veterinary and medical applications, permitting significant cost reductions.

Lee, Susanne M.; Mueller, Eduard K.; Van de Workeen, Brian C.; Mueller, Otward M.

2001-05-01

407

Serous retinal detachment following combined photodynamic therapy and intravitreal bevacizumab injection.  

PubMed

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. PMID:19568365

Kim, Eui Yon; Kim, Jong Wan; Kim, Jun Bum; Lew, Ho Min

2009-06-01

408

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

409

Relevance of PDT-induced inflammatory response for the outcome of photodynamic therapy  

NASA Astrophysics Data System (ADS)

The treatment of solid cancerous lesions by photodynamic therapy (PDT) elicits an acute host reaction primarily manifested as a strong, rapidly developing inflammatory response. It is becoming increasingly clear that the destructive impact of the inflammatory process is directly responsible for the so-called indirect damage in PDT-treated tumors. The loss of vascular homeostasis followed by massive damage to vascular and perivascular regions in PDT- treated tumors and the ensuing tumor antigen-specific immunity, are direct consequences of critical initiating events including the action of complement, activation of poly(ADP-ribose)polymerase (PARP) and ischemia/reperfusion insult, and the associated cascades of tissue-destructive responses. Hence, the effectiveness of PDT as an anti- cancer modality is largely owed to the fact that it instigates a comprehensive engagement of powerful innate host defense mechanisms.

Korbelik, Mladen; Cecic, Ivana; Sun, Jinghai

2001-07-01

410

Corneal heat scar caused by photodynamic therapy performed through an implanted corneal inlay.  

PubMed

A 60-year-old man had a combination of laser in situ keratomileusis and Kamra corneal inlay implantation to correct presbyopia. Although the outcome was favorable postoperatively, central serous chorioretinopathy was observed in the left eye along with a decrease in the uncorrected (UDVA) and corrected (CDVA) distance visual acuities and the corrected near visual acuity (CNVA). Photodynamic therapy (PDT) was later performed in a university hospital. After PDT, the patient experienced a decline in the visual acuity and came to our clinic a month after the PDT. Degeneration and a scar were observed at the location of the inlay due to the heat and burning. Flattening of the corneal topography was also observed where the corneal scar was located, along with a significant decrease in CDVA in the left eye. Prior to any surgery in which the corneal inlay is an impediment, surgeons should take advantage of the reversibility of the Kamra inlay by explanting the inlay. PMID:24160386

Mita, Mariko; Kanamori, Tomomi; Tomita, Minoru

2013-11-01

411

Photodynamic therapy with gold vapor laser in the treatment of bladder cancer  

NASA Astrophysics Data System (ADS)

Vhe paper reports that 149 bladder tumors in 40 patients were treated by gold vapor laser photodynamic therapy in the period from June 1989 to August 1991. The light fiber output power of gold vapor laser is more than 2 W, that spread through a spherical diffuse light leading fiber. Focusing the irradiation on the tumor and the whole bladder the power density was 70.77 mw/cm2 to approximately 509.55 mw/cm2. After a follow-up of 4 to 24 months we found the following results: cured 28 cases (70%); good effect in 11 cases (27.5%); improved 1 case (2.5%); and regenerated 4 (10%).

Zhu, Qing; Zhang, Hui-Guo; Lu, Mei-Er; Zhu, Bang-Ji; Dai, Shen-Guo; Jiang, Yu; Wu, Jia-Jun

1993-03-01

412

Individual in-vitro sensitivities of human pancreatic carcinoma cell lines to photodynamic therapy  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) is a promising alternative in the treatment of pancreatic cancer in man, due to the low sensitivity of the normal pancreas to PDT as shown in preclinical studies. Investigations on four human pancreatic cancer lines (MIA PaCa-2, PaCa 1, PaCa 3, and CAPAN 2) in vitro demonstrated a considerable variety in PDT-sensitivity proportional to the degree of differentiation, which was related to photosensitizer-uptake (PhotofrinTM). The well differentiated pancreatic tumor line Capan 2 showed a close relationship between high cell density and increased PDT-resistance. The Photofrin uptake of Capan 2 at high cell densities could be increased by short trypsinization prior to photosensitizer exposure. The data supports the hypothesis that a complex intercellular organization reduces the cell surface available for photosensitizer uptake and may cause the relative PDT resistance of normal pancreatic tissues and highly differentiated tumors.

Moesta, K. Thomas; Dmytrijuk, Andrew; Schlag, Peter M.; Mang, Thomas S.

1992-06-01

413

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

414

Dye laser photodynamic therapy for Bowen's disease in a patient with epidermodysplasia verruciformis.  

PubMed

Epidermodysplasia verruciformis (EV) is a rare heritable skin disease that results in unusual susceptibility to infection with specific types of human papillomavirus (HPV). Here we report a 53-year-old man with EV who developed Bowen's disease on his lower eyelid and the chest. Mutation analysis of EVER1 gene revealed homozygous splice acceptor site mutation (IVS8-2, A > T). In this patient, HPV3, HPV14, and HPV38 had been identified from the skin lesions. The Bowen's skin lesion on the left lower eye-lid was treated by photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) and pulsed dye laser (PDL). After two rounds of the PDT treatment, the skin lesion disappeared and a skin biopsy confirmed the efficacy of the treatment. This method was simple, less invasive than other treatments, and achieved a satisfactory cosmetic result. PMID:23610850

Sunohara, Mari; Ozawa, Toshiyuki; Morimoto, Kuniyuki; Harada, Teruichi; Ishii, Masamitsu; Fukai, Kazuyoshi

2012-12-01

415

An alternative model for photodynamic therapy of cancers: Hot-band absorption  

NASA Astrophysics Data System (ADS)

The sulfonated aluminum phthalocyanine (AlPcS), a photosensitizer for photodynamic cancer therapy (PDT), has an absorption tail in the near-infrared region (700-900 nm) which is so-called hot band absorption (HBA). With the HBA of 800 nm, the up-conversion excitation of AlPcS was achieved followed by the anti-Stocks emission (688 nm band) and singlet oxygen production. The HBA PDT of AlPcS seriously damaged the KB and HeLa cancer cells, with a typical light dose dependent mode. Particularly, the in vitro experiments with the AlPcS shielding solutions further showed that the HBA PDT can overcome a self-shielding effect benefiting the PDT applications.

Wang, Jing; Chen, Jiyao

2013-12-01

416

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

417

Primary stage of photodestruction of malignant cells under photodynamic therapy of tumors  

NASA Astrophysics Data System (ADS)

In this work we present the experimental results indicating that under photodynamic therapy the primary stage of the photodestruction of malignant cells is based on the irreversible photodestruction of glycolysis enzymes located, first of all, in mitochondria playing a key role in the energy supply for the tumor cells. It was shown that the formation of complexes between glycolysis enzymes and a sensitizer promotes an effective destruction of the formers. The formation of strong complexes was demonstrated for a number of glycolysis enzymes (glyceraldehyde-2-phosphate dehydrogenase, pyruvate kinase, lactate dehydrogenase) with the use of water-soluble pigments chlorin e6 and tetra(carboxyphenyl)porphyrin (T(CP)P) as sensitizers. The direct correlation was shown between the effectiveness of the photodestruction of enzyme molecules and the enzyme-sensitizer binding constant.

Mostovnikov, Vasili A.; Mostovnikova, Galina R.; Plavski, Vitali Y.; Tretjakova, Antonina I.

1996-01-01

418

Ultrastructural changes in Tritrichomonas foetus after treatments with AlPcS4 and photodynamic therapy.  

PubMed

The Tritrichomonas foetus is an amitochondrial parasitic protist which causes bovine trichomoniasis, a major sexually transmitted disease in cattle. No effective drugs for this disease have been approved to this date. Photodynamic therapy (PDT) is an experimental treatment that shows great potential for treating bacteria, fungi, yeasts, and viruses. However, the cytotoxic effect of PDT on protozoan has been poorly studied. In this study, PDT with aluminum phthalocyanine tetrasulfonated (AlPcS4) photosensitizer was efficient in killing T. foetus. The mode of cell death in T. foetus after PDT was investigated by transmission electron microscopy. Morphological changes, such as membrane projections, nucleus fragmentation with peripheral masses of heterochromatin, endoplasmic reticulum proliferation, intense cytoplasmic vacuolization, fragmented axostyle-pelta complex, and internalized flagella could be observed. This is the first report to demonstrate cell death in T. foetus after PDT, and thus will open up new lines of investigation to develop new treatments for bovine trichomoniasis. PMID:17399904

da Silva, Newton Soares; Ribeiro, Claudia de Mello; Machado, Aline Helena Araujo; Pacheco-Soares, Cristina

2007-05-15

419

Fluorescence tissue distribution of methylene blue used for photodynamic therapy of Helicobacter Pylori  

NASA Astrophysics Data System (ADS)

Helicobacter pylori is associated with a wide range of pathologies in the upper gastrointestinal tract. Current treatments employing antibiotics are disappointing, and an endoscopic PDT might offer a better alternative. Methylene blue is a widely known histological dye and has been in use for photodynamic therapy experimentally for some years. A prospective application of MB is photosensitization of Helicobacter pylori, but little is known about its effect with light on normal mucosa of the stomach. We studied the fluorescence microscopy of the stomachs of 3 ferrets which had been sensitized by oral route with three different concentrations of MB 1 hour prior to sacrifice. MB at all doses was seen to concentrate on the surface of the mucosa and shows little deeper penetration. As Helicobacter lie on the superficial mucosa, this study suggests that oral dosing with MB should sensitize these bacteria. These findings are an important preliminary to an in vivo trial of PDT for the treatment of H pylori.

Millson, Charles E.; Buonaccorsi, Giovanni A.; MacRobert, Alexander J.; Mlkvy, Peter; Bown, Stephen G.

1994-10-01

420

Fluorescence tissue distribution of methylene blue used for photodynamic therapy of Helicobacter Pylori  

NASA Astrophysics Data System (ADS)

Helicobacter pylori is associated with a wide range of pathologies in the upper gastrointestinal tract. Current treatments employing antibiotics are disappointing, and an endoscopic PDT might offer a better alternative. Methylene blue is a widely known histological dye and has been in use for photodynamic therapy experimentally for some years. A prospective application of MB is photosensitization of Helicobacter pylori, but little is known about its effect with light on normal mucosa of the stomach. We studied the fluorescence microscopy of the stomachs of 3 ferrets which had been sensitized by oral route with three different concentrations of MB 1 hour prior to sacrifice. MB at all doses was seen to concentrate on the surface of the mucosa and shows little deeper penetration. As Helicobacter lie on the superficial mucosa, this study suggests that oral dosing with MB should sensitize these bacteria. These findings are an important preliminary to an in vivo trial of PDT for the treatment of H pylori.

Millson, Charles E.; Buonaccorsi, Giovanni A.; MacRobert, Alexander J.; Mlkvy, Peter; Bown, S. G.