World Congress of the International Photodynamic Association最新文献

Light-induced permeabilization of liposomes 光诱导脂质体的渗透作用

World Congress of the International Photodynamic Association Pub Date : 2019-08-23 DOI: 10.1117/12.2526071

Paula Enzian, A. Link, C. Schell, Carina Malich, Ramtin Rahmanzadeh

{"title":"Light-induced permeabilization of liposomes","authors":"Paula Enzian, A. Link, C. Schell, Carina Malich, Ramtin Rahmanzadeh","doi":"10.1117/12.2526071","DOIUrl":"https://doi.org/10.1117/12.2526071","url":null,"abstract":"A central challenge in the treatment of different diseases is the delivery of therapeutic agents to a specific cellular site. Liposomes that can release their cargo upon an externally controlled trigger are attractive candidates for localized drug release. Light as external trigger can be controlled temporal and spatial with high precision. In this study, we investigate the potential of light sensitive liposomes with four different photosensitizers for light-induced release. To demonstrate permeabilization of the liposomes, we encapsulated calcein in high concentration inside liposomes, that calcein fluorescence is quenched. If calcein is released from the liposome, quenching is diminished and the fluorescence increases. We demonstrated that liposomes with the sensitizers Benzoporphyrine derivative monoacid (BPD), chlorine e6 (Ce6), Al(III) Phthalocyanine chloride disulfonic acid (AlPcS2) and a di-hydroxyphenyl porphyrine (5,10-DiOH) release cargo effectively after irradiation. Liposomes with 5,10-DiOH showed a quicker release compared to the other sensitizers. Further we observed through fractionated irradiation, that most of the release took place during light irradiation, while the permeability of the liposome decreased shortly after light exposure.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128149193","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}

引用次数: 0

Clinical evaluation of smartphone-based fluorescence imaging for guidance and monitoring of ALA PDT 基于智能手机的荧光成像对ALA PDT指导和监测的临床评价

World Congress of the International Photodynamic Association Pub Date : 2019-08-12 DOI: 10.1117/12.2526116

Shakir Khan, M. Hussain, Amjad P. Khan, Hui Liu, S. Siddiqui, S. Mallidi, Paola Leon, Liam Daly, Grant Rudd, Filip Cuckov, C. Hopper, S. Bown, S. Siddiqui, J. Celli, T. Hasan

{"title":"Clinical evaluation of smartphone-based fluorescence imaging for guidance and monitoring of ALA PDT","authors":"Shakir Khan, M. Hussain, Amjad P. Khan, Hui Liu, S. Siddiqui, S. Mallidi, Paola Leon, Liam Daly, Grant Rudd, Filip Cuckov, C. Hopper, S. Bown, S. Siddiqui, J. Celli, T. Hasan","doi":"10.1117/12.2526116","DOIUrl":"https://doi.org/10.1117/12.2526116","url":null,"abstract":"India has one of the highest rates of oral cancer incidence in the world, with an estimated 80,000 new cases per year, accounting for 30% of reported cancers. In rural areas, a lack of adequate medical infrastructure contributes to unchecked disease progression and dismal mortality rates. PDT emerges as a potential modality which can be implemented in resource limited settings, while photosensitizer fluorescence can be leveraged for treatment guidance. Here, as part of an ongoing clinical study evaluating low-cost technology for ALA PDT treatment, we evaluated the capability of a simple smartphone-based device for imaging ALA-induced PpIX fluorescence. The imaging device itself consists of an annulus of 405nm LEDs for PpIX excitation with emission filter in the center mounted over the phone camera. 18 subjects having <2 cm diameter (mean size; ~1.38 cm2) lesions with micro-invasive (≤5 mm. depth) moderately/well-differentiated squamous cell carcinoma were administered 60 mg/kg ALA in oral solution and imaged before and after delivery of 100 J/cm2 total light dose to the lesion surface. We will present comparative analysis of pre-and post-treatment fluorescence, white light, and ultrasound images. In general, PpIX fluorescence images obtained prior to therapeutic light delivery are able to resolve lesion margins while dramatic photobleaching in post-treatment images confirms the irradiated zone. Overall this approach is able to generate sufficient fluorescence contrast for treatment guidance and monitoring photobleaching while the use of a smartphone-based device provides a low-cost, widely available platform with potential for telemedicine integration.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132818338","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}

引用次数: 1

Cyclodextrin-based photoactive liposomal nanoparticles for tumor targeting 靶向肿瘤的环糊精光活性脂质体纳米颗粒

World Congress of the International Photodynamic Association Pub Date : 2019-08-07 DOI: 10.1117/12.2524210

I. Yakavets, H. Lassalle, V. Zorin, L. Bezdetnaya

{"title":"Cyclodextrin-based photoactive liposomal nanoparticles for tumor targeting","authors":"I. Yakavets, H. Lassalle, V. Zorin, L. Bezdetnaya","doi":"10.1117/12.2524210","DOIUrl":"https://doi.org/10.1117/12.2524210","url":null,"abstract":"The present study is aimed at the development of drug-in-cyclodextrin-in-liposome (DCL) nanoconstruct by coupling two independent delivery systems: cyclodextrin/mTHPC inclusion complexes and liposomal vesicles to improve the transport of mTHPC to the target tissue and to strengthen its intra-tissue accumulation in the tumor. Liposomes offer an excellent opportunity to achieve selective drug, targeting what is expected to prevent local irritation and reduce drug toxicity. Сyclodextrins (CDs) have been utilized as independent carriers for improvement of pharmaceutical properties such as solubility, stability, and bioavailability of various drug molecules, including mTHPC. Therefore, we assumed that encapsulation of CD-complexed drug into liposomes might increase drug loading capacity, entrapment efficiency, may restrain the dissociation of drug-CD complexes and prolong its systemic circulation. DCL nanoparticles have been prepared with various compositions to optimize the structure aiming to alter more favorably the distribution of temoporfin in tumor tissue. To enhance the encapsulation efficiency, double loaded DCLs, which include mTHPC in lipid bilayer along with (CD-mTHPC) inclusion complexes in the inner aqueous lumen, were prepared. It was demonstrated that DCLs possessed higher serum stability compared with conventional mTHPC liposomes (Foslip). In fine, we showed that the presence of serum in the medium less affected cellular uptake of mTHPC delivered by double loaded MDCL compared with Foslip.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"1 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":"124835116","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}

引用次数: 2

Photodynamic therapy of basal cell carcinoma with Levulon local application levvulon局部应用光动力治疗基底细胞癌

World Congress of the International Photodynamic Association Pub Date : 2019-08-07 DOI: 10.1117/12.2525825

E. Filonenko, A. Kaprin, A. Urlova, N. Grigorievykh

引用次数: 2

A pilot study of antimicrobial photodynamic therapy of encapsulated Aspergillus fumigatus in a rabbit maxillary sinus model 包封烟曲霉抗菌光动力治疗兔上颌窦模型的初步研究

World Congress of the International Photodynamic Association Pub Date : 2019-08-07 DOI: 10.1117/12.2526225

C. Romo, N. Loebel, D. Meller, R. Andersen

引用次数: 3

Antimicrobial effects of Photodynamic Therapy to gram negative bacteria envelope revealed by Cryo-electron tomography 光动力疗法对革兰氏阴性菌包膜的抑菌作用

World Congress of the International Photodynamic Association Pub Date : 2019-08-07 DOI: 10.1117/12.2525451

A. Garcez, M. Kaplan, S. Núñez, G. Jensen

{"title":"Antimicrobial effects of Photodynamic Therapy to gram negative bacteria envelope revealed by Cryo-electron tomography","authors":"A. Garcez, M. Kaplan, S. Núñez, G. Jensen","doi":"10.1117/12.2525451","DOIUrl":"https://doi.org/10.1117/12.2525451","url":null,"abstract":"Cryo-electron tomography (cryo-ET) is an emerging technology that enables thin samples, including small intact prokaryotic cells, to be imaged in three dimensions in a near-native 'frozenhydrated' state to a resolution sufficient to recognize very large macromolecular complexes in situ. This methodology has been fundamental to provide information about cellular ultrastructure. This study used cryo-ET to evaluate the photodynamic effect on the viability and envelope architecture of a Gram-negative bacteria. Bacterial suspension of E. coli minicells were submitted to photodynamic treatment with methylene blue solution (100μM) and a 100mW low power diode laser emitting at 660nm with 6 and 18J of energy. As a control group, a suspension of minicells were submitted to 462 IU/mL penicillin G for 60 min at 30 °C, to compare the damage in cell wall structure. After treatment bacteria were immediately plunge-frozen across EM grids and standard cryo-ET tilt series were collected, 3D images reconstructions were calculated and recorded. The imagens showed detachment of the bacterial cell walls and mesosome-like structures. In addition, some sites showed interrupted stretches in both inner and outer membranes and cell wall degradation, indicating bacterial envelope damage. Cryo-electron tomography revealed that the effects of photodynamic therapy on Gram negative bacteria was based on damage to the outer membrane, cell wall and inner membrane and occurs in an energy-dependent manner.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"19 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":"122990557","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}

引用次数: 0

Photodynamic inactivation of Candida albicans using a synthesized bacteriochlorin as a photosensitizer 利用合成的细菌氯作为光敏剂进行白色念珠菌的光动力灭活

World Congress of the International Photodynamic Association Pub Date : 2019-08-07 DOI: 10.1117/12.2526403

Laura C. A. Martins, T. Q. Corrêa, S. Pratavieira, M. P. Uliana, K. D. de Oliveira, V. Bagnato, C. D. de Souza

{"title":"Photodynamic inactivation of Candida albicans using a synthesized bacteriochlorin as a photosensitizer","authors":"Laura C. A. Martins, T. Q. Corrêa, S. Pratavieira, M. P. Uliana, K. D. de Oliveira, V. Bagnato, C. D. de Souza","doi":"10.1117/12.2526403","DOIUrl":"https://doi.org/10.1117/12.2526403","url":null,"abstract":"In this study, Candida albicans in its planktonic form, was used as target microorganism. This species frequently appears in superficial and invasive infections because of its pathogenic potential, and it is becoming highly resistant. Bacteriochlorin was used as a photosensitizer, presenting absorption around 780 nm and low toxicity in the absence of light. The objective was to evaluate its photodynamic inactivation potential in Candida albicans. The photosensitizer was synthesized from the extraction of bacteriochlorophylls derived from non-sulfurous purple bacteria and the converted to bacteriochlorin. The inoculum of Candida albicans was grown for 24 hours and adjusted to the concentration of 106 CFU/mL. The device used for the emission of light was a homemade device with LEDs of 780 nm wavelength. The quantitative evaluation of viable cells was performed by spread plate in Sabouraud Dextrose Agar. The results showed that this new bacteriochlorin is not much stable in its absorption peak, being necessary a better chemical characterization to verify its antimicrobial potential.","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":"129143698","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}

引用次数: 1

Optical techniques for the microbiological control of blood 血液微生物控制的光学技术

World Congress of the International Photodynamic Association Pub Date : 2019-08-07 DOI: 10.1117/12.2524885

T. Q. Corrêa, K. Blanco, N. Inada, C. Kurachi, V. Bagnato

{"title":"Optical techniques for the microbiological control of blood","authors":"T. Q. Corrêa, K. Blanco, N. Inada, C. Kurachi, V. Bagnato","doi":"10.1117/12.2524885","DOIUrl":"https://doi.org/10.1117/12.2524885","url":null,"abstract":"Blood can be the target of bacterial, viral and parasitic contamination, which can trigger serious diseases. In this study, photodynamic inactivation and ultraviolet radiation were evaluated in the in vitro decontamination of whole blood, erythrocytes, and platelet-rich plasma with S. aureus. For PDI, Photogem and 630 nm light were evaluated, and risks of toxicity of the treatment were determined by hemolysis and cell viability assays. The reductions of S. aureus in whole blood, erythrocytes, and platelet-rich plasma at 15 J/cm2 and 50 μg/mL porphyrin were 1.0 log, 1.3 log and 0.4 log CFU/mL, respectively. Hemolysis rate for erythrocytes in whole blood was 10.7%. However, erythrocytes hemolysis was 100% when in the absence of plasma. The cell viability assay showed 14% apoptosis rates in isolated erythrocytes, indicating damaging action of PDI, and no damage in platelet. For UVC radiation (254 nm), different light doses were analyzed, and the cell viability assay determined the toxicity of technique. The reductions of S. aureus in whole blood, erythrocytes and platelet-rich plasma at 23 J/cm2 were 1.7 log, 1.1 log and 2.5 log CFU/mL, respectively. Relatively small differences were observed in plasma as a function of irradiation time, suggesting some degradation of plasma proteins with 23 J/cm2. The cell viability assay showed normal rates for erythrocytes, however, in the platelets, a high apoptosis rate was observed (74%). Therefore, the optical techniques showed opposite damage effects in each blood component, and the use of one or another technique should be evaluated considering the better microbial inactivation and blood components preservation conditions.","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":"129094739","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}

引用次数: 0

Autofluorescence endoscopic surveillance and photodynamic treatment of Barrett's esophagus Barrett食管的自体荧光内镜监测和光动力治疗

World Congress of the International Photodynamic Association Pub Date : 2019-08-07 DOI: 10.1117/12.2525522

W. Latos, A. Sieroń, G. Cieślar, A. Kawczyk-Krupka

{"title":"Autofluorescence endoscopic surveillance and photodynamic treatment of Barrett's esophagus","authors":"W. Latos, A. Sieroń, G. Cieślar, A. Kawczyk-Krupka","doi":"10.1117/12.2525522","DOIUrl":"https://doi.org/10.1117/12.2525522","url":null,"abstract":"Background. This study assessed the efficacy of autofluorescence endoscopy (AFE) using the Onco-LIFE system and numerical color value (NCV) estimation in comparison to white light endoscopy (WLE) in endoscopic surveillance for identification of early dysplasia in Barrett’s esophagus (BE). In the case of dysplasia photodynamic treatment (PDT) was carried out. Methods. AFE, performed simultaneously during WLE, with biopsy was performed in 24 patients with BE. None of these patients had any obvious mucosal abnormalities in WLE. A total of 376 biopsies were taken, include 325 randomly collected according to Seattle Protocol (SP) and 51 additional biopsies, taken from the sites with pathological AF and NCV, and then compared to histological examinations. The PDT was performed using 5-aminolevulinic acid (ALA) and DIOMED 630nm light source. Results. In the case of 248 biopsies taken from sites with NCV below 1.0, two cases of unspecified dysplasia were recognized; in 14 biopsies with NCV above 2.0 in all cases the various grades of dysplasia were documented. Dysplasia was found in 42% of AFE+NCV- guided biopsy specimens, and in 7.1% of WLE-guided biopsy specimens. AFE+NCV detected high-grade dysplasia in 7 patients, 6 more than according to SP in WLE. In the group patients with dysplasia, PDT was successfully carried out. Conclusion: The results indicate that AFE+NCV using the Onco-LIFE system leads to improved BE lesion visualization for targeted biopsy with accurate histologic correlation compared to WLE and SP guided biopsy, and can serve to minimize additional biopsies. PDT is an effective therapeutic method in BE.","PeriodicalId":267589,"journal":{"name":"World Congress of the International Photodynamic Association","volume":"12 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":"126333110","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}

引用次数: 0

Photodynamic therapy activity of new porphyrin-xylan-coated silica nanoparticles in a human colorectal cancer in vivo model 新型卟啉-木聚糖包覆二氧化硅纳米颗粒在人结肠直肠癌体内模型中的光动力治疗活性

World Congress of the International Photodynamic Association Pub Date : 2019-08-07 DOI: 10.1117/12.2525033

L. Bretin, D. Léger, A. Pinon, Soukaina Bouramtane, Frédérique Brégier, Vincent Sol, V. Chaleix, B. Liagre

引用次数: 2