World Congress of the International Photodynamic Association最新文献

{"title":"Antimicrobial photodynamic therapy: from basis to clinical applications","authors":"M. Ribeiro, C. Sabino, S. Núñez","doi":"10.1117/12.2527918","DOIUrl":"https://doi.org/10.1117/12.2527918","url":null,"abstract":"Antimicrobial photodynamic therapy (APDT) combines the use of light with a photosensitizer (PS) and oxygen to kill microbial cells. Even though this technique was first reported in the beginning of the 20th century, APDT never took off as antimicrobial chemotherapy did. However, microbial resistance to chemotherapy is currently expanding in faster rates than drug discovery. Therefore, introduction of therapeutic alternatives that bypass mechanisms of drug resistance now presents an urgent status. Fortunately, the scientific and technological development related to APDT made it far more feasible for mainstream clinical applications. Our research group has been working on mechanisms and applications of APDT for almost 20 years. We have already reported that successful APDT results depend on a number of factors, such as PS and light parameters, cell type, and oxygen abundance, among others. We have also demonstrated that APDT is an effective adjuvant in endodontics and periodontics and can be a non-invasive treatment for caries, candidiasis and cutaneous leishmaniasis. In Veterinary Medicine, we have reported effective treatment for penguin pododermatitis, snake stomatitis and dog otitis. This presentation will give an integrated perspective from the basic APDT mechanisms, preclinical and clinical trials to protocol optimization and future perspectives.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"89 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124161578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of nano immunotherapy drug delivery in lung cancer cells","authors":"C. A. Kruger, M. Mokwena, H. Abrahamse","doi":"10.1117/12.2514043","DOIUrl":"https://doi.org/10.1117/12.2514043","url":null,"abstract":"Lung cancer has high incidence and mortality rates worldwide and so there is strong need for the development of novel therapies. Photodynamic therapy (PDT) is a photochemotherapeutic cancer treatment that utilizes a photosensitizer (PS) drug that, when activated by laser light at a specific wavelength, yields reactive oxygen species, which in turn induces cell death. However, due to the passive diffusion of PSs, normal surrounding cells are sometimes affected and their targeted concentrations in cancer cells tends to be minimal, thus limiting the effectiveness of this treatment. Therefore, a multicomponent drug targeting strategy is often applied to improve PS specific delivery and concentration in cancer cells, which in turn can improve the effectiveness of PDT. The intention of this study was to improve the PS drug delivery of Zn(II) Phthalocyanine tetrasulfonic acid (ZnPcS4) in lung cancer cells, by enhancing its chemical structure. ZnPcS4 was successfully conjugated to pegylated gold nanoparticles in order to maximize its solubility and stability, as well as bound to specific active tumour-associated antibody-antigens (Cetuximab: Anti-EGFR1 Ab) to aid specific targeted PS delivery. Within in vitro cultured lung cancer cells, this molecular drug delivery system noted improved and specific sub-cellular location of ZnPcS4. Furthermore, after conducting in vitro PDT experiments, a significant amount of cell death and cytotoxicity was found. Overall, this nano immunotherapy drug conjugation combination of ZnPcS4 with AuNP and Cetuximab, proved to enhance concentrated PS uptake in lung cancer cells and so improve PDT treatment outcomes for this form of cancer.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124673523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DOSINDYGO: DOSe finding for INtraoperative photoDYnamic therapy of GliOblastoma","authors":"C. Dupont, F. Lecomte, P. Deleporte, G. Baert, S. Mordon, N. Reyns, M. Vermandel","doi":"10.1117/12.2524949","DOIUrl":"https://doi.org/10.1117/12.2524949","url":null,"abstract":"Glioblastoma is a malignant brain tumor with a poor prognosis. Currently, complete resection is rarely feasible, since tumor cells usually infiltrate the surrounding brain. Recently, the INDYGO clinical trial has been achieved to assess the toxicity of photodynamic therapy (PDT) delivered intraoperatively to treat newly diagnosed glioblastoma. Today, we believe that the PDT effect obtained in the INDYGO clinical trial can be improved by a higher light dose. The DOSINDYGO clinical trial aims to achieve a light-dose escalation increasing up to four times the initial light dose used in the INDYGO trial. An increase of both light power and treatment time should allow to treat deeper in the surrounding tissues (up to 8mm) and thus decrease the recurrence risk. First light dose will be reached by doubling the treatment time used in the INDYGO trial, the other one will be achieved by increasing light power only. This methodology was chosen in order to maintain an acceptable treatment time for anesthesia but also to prevent higher fluence rate that could induce a lower tolerance as observed in our preclinical results. Primary endpoint will be to determine the optimum light-dose regarding the ratio efficacy and tolerance of the treatment. Primary criterion is the assessment of the progression free survival within the bed border’s cavity. Finally, although no adverse effect has been noticed during the INDYGO trial, increasing light dose in this DOSINDYGO trial could result in other direct and indirect biological effects.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"161 7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129088738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Singlet oxygen formation in photodynamic therapy using guaiazulene and red laser: an in vitro study","authors":"Ampika Mangkhalathon, Aroon Teerakapong, N. P. Morales, S. Morkmued, Teerasak Damrongrungruang","doi":"10.1117/12.2525414","DOIUrl":"https://doi.org/10.1117/12.2525414","url":null,"abstract":"Guaiazulene is one of the natural azulene derivatives, which has anti-inflammatory as well as photosensitizer property and can be activated by highly penetrating red light. The proper singlet oxygen from this activation will lead to a useful strategy for specific treating unwanted cells. Objective: To measure in vitro amount of singlet oxygen produced from PDT reaction using various guaiazulene concentrations and red laser energies. Methods: Guaiazulene were prepared by diluting in methanol and mixed with 2,2,5,5-tetramethyl-3-pyrroline-3-carboxamide (TPC) to obtain 1, 2, 5, 15, 25, 35, 100, and 500 μM. Erythrosine (10 μM in each light energies) were used as positive control. Then, irradiations were performed with various red laser energies (625 nm, 151.5 mW/cm2, distance from laser tip to bottom of the well = 8 mm, and continuous mode) at 0, 4, and 8 J/cm2 in a black 96-well plate. The amount of singlet oxygen was measured in triplicate by electron spin resonance spectrometer (Bruker, Germany) at 0, 3, and 5 minutes after irradiation. Kruskal-Wallis and Mann-Whitney U test were used for statistical analyses with significant differences at p-value < 0.05. Results: The average singlet oxygen of 5 μM group significantly different from no guiazulene group (p < 0.01). Regarding the energy, both 4 and 8 J/cm2 resulted in relatively equal amounts of singlet oxygen. Conclusion: Five μM of guaiazulene activated by 625 nm laser at energy densities 4 - 8 J/cm2 dramatically generated singlet oxygen in current in vitro setting.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122103212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antimicrobial PDT in South America","authors":"L. M. de Freitas, M. Baptista","doi":"10.1117/12.2527507","DOIUrl":"https://doi.org/10.1117/12.2527507","url":null,"abstract":"Researchers all over the world have turned their attention to find novel antibiotics and non-antibiotic-based alternatives to fight infections caused by resistant bacteria. Among the alternatives, antimicrobial photodynamic therapy (aPDT) has gained attention due to its non-specific nature of killing, which is unlikely to induce new forms of resistance due mainly to its broad spectrum of action. Most research groups working in aPDT are based in the North and South Americas, and Brazil leads this research field, accounting for 26% of all the aPDT publications in the world, 55% of the Americas and more than 95% of the publications in South America alone. As far as the databases show, aPDT is the only research topic in which Brazil publishes more papers than any other country in the world. Brazilian researchers have been contributing extensively to unveil molecular mechanisms of aPDT, developing treatment protocols for oral, dermatologic and veterinary infections, and to improve and optimize the technique so it can finally become a clinical reality. However, if one analyses the average citation per paper, one will find that Brazilian papers, although abundant, receive fewer citations than almost all other countries in the top 10. This finding is not specific to this area of research since other scientometric studies have shown the same profile in many other research areas. The low global impact of Brazilian – and South America’s - research might be due to the immaturity of our community and/or unfamiliarity or lack of access to techniques that can help improve the robustness of the work. Therefore, collaborations among aPDT groups can be of the utmost importance in increasing the impact of science in South America. In this paper, we cover the numbers of South America’s research and provide a full network list to encourage scientific collaborations.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125674146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of protoporphyrin IX production induced by aminolevulinic acid combined with thermogenic and/or vasodilator substances","authors":"M. D. Stringasci, J. D. Vollet Filho, L. Moriyama, C. Kurachi, V. Bagnato","doi":"10.1117/12.2525696","DOIUrl":"https://doi.org/10.1117/12.2525696","url":null,"abstract":"One of the limiting factors of photodynamic therapy is cutaneous permeation of a photosensitizer or precursor. Studies report that there is a strong relationship between temperature and porphyrin synthesis in biological tissue. The use of thermogenic and/or vasodilator substances may favor both ALA/methyl-ALA permeation and protoporphyrin IX (PpIX) production in the tissue. In this study, menthol, methyl nicotinate, and ginger extract were incorporated into either the ALA or methyl-ALA cream to investigate the PpIX production in rat skin. Fluorescence spectra were collected to quantify the PpIX present in tissues. The methyl nicotinate was the one with the highest optimization effect of PpIX production after three hours of incubation of the cream. Its association with methyl-ALA caused the production to be about 50% higher than that observed for methyl-ALA alone. These results are promising as a possible strategy for decreasing the incubation time of the precursor cream in various clinical protocols and increasing the photosensitizer production in lesions.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"258 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115597273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TSPO-targeted agents for PDT of aggressive tumors (Withdrawal Notice)","authors":"Meng Su, Qing Xie, Dawei Zhang, M. Bai","doi":"10.1117/12.2525334","DOIUrl":"https://doi.org/10.1117/12.2525334","url":null,"abstract":"This paper, originally published on 7 August 2019, was withdrawn at the request of the authors on 12 August 2019.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"491 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124433051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Possible approaches to fluorescence diagnosis and photodynamic therapy for deep-seated tumors","authors":"V. Loschenov, T. Savelieva, P. Grachev, K. Linkov, Yuliya Maklygina, I. Romanishkin, A. Ryabova, D. Kustov, S. Goryajnov, A. Potapov","doi":"10.1117/12.2526013","DOIUrl":"https://doi.org/10.1117/12.2526013","url":null,"abstract":"The limited penetration of laser radiation into biological tissue prevents the widespread distribution of photodiagnostics (PD) and photodynamic therapy (PDT) methods to clinical practice. We have investigated several approaches for PD and PDT of deep-seated tumors: 1. Stereotactic biopsy cannula with a laser spectroscopic control. Special fiber ports for long-term installation in the tumor removal area were developed in order to cause tumor cells to migrate not into the depth of brain but along the fibers with occasional laser irradiation for PD and PDT. The fibers are coated with a special compound containing photosensitizer (PS) and nutrients for cancer cells. 2. Neurosurgical aspirator with the function of video-fluorescence and spectroscopic analysis system. More than 500 patients with various types of brain tumors were operated on using fluorescent navigation based on 5-aminolevulinic acid (5-ALA) induced protoporphyrin IX (Pp IX) fluorescence under laser excitation in red spectral range. 3. Diagnostics and navigation of tumors when fluorescence is excited in the red and near infrared ranges. We used indocyanine green (ICG) as near infrared dye to observe blood and lymph vasculature of laboratory animals. This method could be useful while examining tumor bed and adjacent area. 4. Joint action of radiopharmaceuticals and PS based on Cherenkov radiation. Cell death by PDT mechanism via Pp IX excitation by Cherenkov radiation in mitochondria during 18F-fludeoxyglucose decay. This idea achieved good results on rats with C6 glioma. The results of using this approach with chlorin e6 PS in comparable doses are negative. 5. Action through photodynamic inactivation of tumor-associated macrophages and microglia. Idea of minimally invasive method for determining macrophage (microglia) phenotype and their polarization in tumors and their immediate vicinity in situ. This would allow evaluating the effectiveness of the treatment, including PDT. The most promising results were obtained with Pp IX and aluminum phthalocyanine nanoparticles. Studies have been conducted on experimental animals with grafted tumors and, in part, on cancer patients in the clinic.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"11070 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129937024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-term effectiveness and HPV clearance of low and high-grade cervical lesions treated with photodynamic therapy","authors":"N. Inada, C. A. de Castro, H. Buzzá, W. Lombardi, V. Bagnato","doi":"10.1117/12.2524706","DOIUrl":"https://doi.org/10.1117/12.2524706","url":null,"abstract":"Cervical cancer is the fourth most frequent cancer in women worldwide. For Brazil, there are estimated 16,370 new cases of cervical cancer for each year of the biennium of 2018-2019, with an estimated risk of 15.43 cases per 100,000 women, occupying the third position [1]. Persistent infection with Human papillomavirus (HPV) has been identified as the major cause of the Cervical Intraepithelial Neoplasia (CIN), a precursor of cervical cancer. The classification of CIN is based on the cellular features to discriminate dysplasia levels, being CIN 1 as mild dysplasia and CIN 2/3 as moderate or severe dysplasia [2]. Cervical cancer can be prevented with a early CIN diagnosis and treatment [3].","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"138 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133165562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A lead BODIPY-phenylanthracene dyad for application in photodynamic therapy","authors":"S. Callaghan, M. Filatov, H. Savoie, R. Boyle, M. Senge","doi":"10.1117/12.2525246","DOIUrl":"https://doi.org/10.1117/12.2525246","url":null,"abstract":"Over the past four years we have developed BODIPY dyads capable of triplet state generation from charge transfer states generated by photoinduced electron transfer. In the current work we identify a lead compound for application in photodynamic therapy. This system is composed of a phenylanthracene electron donor unit and a dimethyl-substituted BODIPY acceptor unit. We have demonstrated that this compound, in sub-micromolar concentrations, can effectively generate singlet oxygen in polar solvents and induce cytotoxicity in human breast cancer cells (MDA-MB-468) when exposed to light. The photophysical properties of these compounds are chemically tunable and thus open the door not only to a new class of photodynamic therapy photosensitizers, but also agents for triplet-triplet annihilation up-conversion applications.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"138 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134019694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}