This PDF file contains the front matter associated with SPIE Proceedings Volume 11939, including the Title Page, Copyright information, Table of Contents, and Conference Committee listings.

Atopic dermatitis (AD) is a common inflammatory skin disorder which affects ~20% of children and ~3% adults worldwide. There lacks a direct, non-invasive method of evaluating atopic dermatitis (AD) accurately. Here, the use a multispectral raster-scanning optoacoustic mesoscopy (MS-RSOM) as an objective imaging tool for AD is proposed. MS-RSOM is a novel, non-invasive optoacoustic imaging modality which can provide label-free, high resolution imaging up to 1.5 mm below the skin. It can provide useful information on melanin, oxyhemoglobin (HbO₂), deoxyhemoglobin (Hb) and oxygen saturation (sO₂) from the skin layers. This preliminary study was conducted on 4 AD patients and 2 healthy volunteers using MS-RSOM system. From the MS-RSOM images, the epidermis thickness and oxygen saturation were computed from the healthy volunteers as well as from the non-lesional and eczema lesional areas of the eczema subjects.

Antimicrobial photodynamic therapy (aPDT) in combination with antibiotics leads to a notable reduction in antibiotic minimum inhibitory concentration (MIC). Four antibiotic resistant bacterial strains (E. faecalis OG1RF(+), P. aeruginosa PA01, K. pneumoniae, E. coli ETEC) were evaluated with four antibiotics (ampicillin, kanamycin, tetracycline, chloramphenicol) in a combination treatment with methylene blue aPDT. Treatment involved co-culture of antibiotics with 1.0 μ𝑀 MB followed by exposure to 0 to 14.4 ^𝐽 _𝑐𝑚² of light over 0 to 10 minutes at a rate of 30 ^𝑚𝑊 _𝑐𝑚². MIC of test groups was compared to controls to evaluate direct effects on resistance, and further aPDT controls were used to evaluate measures of synergistic effect based on fractional inhibitory concentration index (FICI). It was found that 12 of 16 strain-antibiotic combinations have a reduction in antibiotic resistance during treatment, two of which are statistically significant. The calculated FICI values for these combinations contain 6 indifferent values between 1.0 and 1.5 and 10 additive values at or below 1.0, one of which was 0.43, qualifying as synergistic treatment. Overall, this survey provides a brief exploration of aPDT as an adjunct therapy for combatting antibiotic resistant bacteria. Further targeted research on strain-antibiotic combinations of interest may reveal valuable synergistic effects.

Companion and farm animals can be an important source of antimicrobial-resistance microorganisms. In pets like dogs and cats, urinary tract infections (UTI) are a common reason for using antibiotics, often prescribed empirically due to the high costs and long duration of the official laboratory tests. Therefore, chromogenic agars for in-clinic use have recently appeared, which offer bacteria species identification and antimicrobial susceptibility testing (AST). In our work, we employed machine vision for colony color and diameter determination of some prevalent companion animal bacteria, which grew after 24 or 48 hours of incubation on the commercially available chromogenic agar Uriselect. We analyzed 26 samples, including Staphylococcus pseudintermedius (10), Staphylococcus felis (4), Escherichia coli (4), Enterococcus faecalis (4), and Pseudomonas aeruginosa (4). Results showed that E. coli and Ent. faecalis exhibited unique colony colors (red, blue) and diameter (larger or smaller). Furthermore, the colony size did not change significantly during the entire incubation time. On the other hand, both staphylococcus colonies were small initially, but their size almost tripled in the following 24 hours, when colonies finally exhibited a pink color. P. aeruginosa proved to be orange-green. This study showed that our optical system could detect uniquely colored and sized canine and feline bacteria colonies, which grew on Uriselect chromogenic agar.