Dr. Laura Marise de Freitas Profile

Dr. Laura Marise de Freitas

Doctoral Candidate at UNESP

SPIE Involvement:

Author

Publications (2)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 7 August 2019 Paper

Antimicrobial PDT in South America

Laura de Freitas, Maurício Baptista

Proceedings Volume 11070, 110708L (2019) https://doi.org/10.1117/12.2527507

KEYWORDS: Bacteria, Photodynamic therapy, Databases, Resistance

Read 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.

Proceedings Article | 14 March 2018 Presentation

Antimicrobial photodynamic therapy proved not to induce bacterial resistance (Conference Presentation)

Laura de Freitas, Ana Blanco, Carla Fontana

Proceedings Volume 10479, 1047919 (2018) https://doi.org/10.1117/12.2287268

KEYWORDS: Resistance, Photodynamic therapy, Picosecond phenomena, Oxygen, Therapeutics, Plating, Blood

Read Abstract +

The World Health Organization has been alerting that the “post-antibiotic era” is approaching, making the search for alternative antimicrobial therapies mandatory. Antimicrobial photodynamic therapy (aPDT) has been gaining prominence due to its non-specific mechanism of action, which relies on the generation of reactive oxygen species upon the activation of a photosensitizer (PS) by light of a specific wavelength in the presence of oxygen. However, the discussion of whether or not aPDT can induce bacterial resistance is controversial. In that sense, the aim of this study was to determine if multiple cycles of suboptimal doses of aPDT could induce resistance in Enterococcus faecalis. First, we determined optimal and suboptimal conditions of aPDT employing chlorin-e6 (Ce6) and methylene (MB) for planktonic E. faecalis. The combinations of light dose and PS concentration that induced bacterial reductions between 1 log10 and 3 log10 of CFU/mL were selected to start the cycles (21 µM of Ce6 + 45 J/cm²; and 78 µM of MB + 80 J/cm²). The cycling consisted of treatment, plating on PS-free blood agar and recovering grown colonies to start again. By the end of four cycles, cells treated with both Ce6-aPDT or MB-aPDT were completely eliminated, after sustaining a stable survival rate through the first three cycles. We employed two different PS and observed the same outcomes for both of them, indicating the results were not PS-dependent. Our findings are of paramount importance since they are in the way to prove that bacterial resistance cannot be induced by this approach.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

;

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years