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Near‐Infrared‐II (NIR‐II) spans wavelengths between 1,000 to 1,700 nanometers, featuring deep tissue penetration and reduced tissue scattering and absorption characteristics, providing robust support for cancer treatment and tumor imaging research. This review explores the utilization of activatable NIR‐II photodiagnosis and phototherapy based on tumor microenvironments (e. g. reactive oxygen species, pH, glutathione, hypoxia) and external stimulation (e. g. laser, ultrasound, photothermal) for precise tumor treatment and imaging. Special emphasis is placed on the advancements and advantages of activatable NIR‐II nanomedicines in novel therapeutic modalities like photodynamic therapy, photothermal therapy, and photoacoustic imaging. This encompasses achieving deep tumor penetration, real‐time monitoring of the treatment process, and obtaining high‐resolution, high signal‐to‐noise ratio images even at low material concentrations. Lastly, from a clinical perspective, the challenges faced by activatable NIR‐II phototherapy are discussed, alongside potential strategies to overcome these hurdles. [ABSTRACT FROM AUTHOR]

Paracoccidioidomycosis (PCM) is a systemic mycosis that is diagnosed by visualizing the fungus in clinical samples or by other methods, like serological techniques. However, all PCM diagnostic methods have limitations. The aim of this study was to develop a diagnostic tool for PCM based on Fourier transform infrared (FTIR) spectroscopy. A total of 224 serum samples were included: 132 from PCM patients and 92 constituting the control group (50 from healthy blood donors and 42 from patients with other systemic mycoses). Samples were analyzed by attenuated total reflection (ATR) and a t-test was performed to find differences in the spectra of the two groups. The wavenumbers that had p < 0.05 had their diagnostic potential evaluated using receiver operating characteristic (ROC) curves. The spectral region with the lowest p value was used for variable selection through principal component analysis (PCA). The selected variables were used in a linear discriminant analysis (LDA). In univariate analysis, the ROC curves with the best performance were obtained in the region 1551–1095 cm−1. The wavenumber that had the highest AUC value was 1264 cm−1, achieving a sensitivity of 97.73%, specificity of 76.01%, and accuracy of 94.22%. The total separation of groups was obtained in the PCA performed with a spectral range of 1551–1095 cm−1. LDA performed with the eight wavenumbers with the greatest weight from the group discrimination in the PCA obtained 100% accuracy. The methodology proposed here is simple, fast, and highly accurate, proving its potential to be applied in the diagnosis of PCM. The proposed method is more accurate than the currently known diagnostic methods, which is particularly relevant for a neglected tropical mycosis such as paracoccidioidomycosis. [ABSTRACT FROM AUTHOR]

Photodiagnosis (PD) and photodynamic therapy (PDT) using the second-generation photosensitizer talaporfin sodium together with an exciting laser for primary intracranial malignant tumors is well recognized in Japan, and many medical institutions are introducing this new therapeutic option. In particular, intraoperative PDT using talaporfin sodium for infiltrating tumor cells in the cavity walls after the resection of malignant glioma is now covered by health insurance after receiving governmental approvement, and this method has been recommended in therapeutic guidelines for primary malignant brain tumors in Japan. On the other hand, experimental and clinical studies on the development of novel therapeutic strategies for malignant spinal cord tumors have not been reported to date, although their histological features are almost identical to those of intracranial malignant tumors. Therefore, the clinical outcomes of malignant spinal cord tumors have been less favorable than those of malignant brain tumors. In this report, we performed the PD and PDT using talaporfin sodium on a patient with a metastatic lumbar lesion that was detected on magnetic resonance image (MRI) 50 months after the resection of cerebellar medulloblastoma who presented with lumbago and sciatica. We were able to detect the target lesion in the conus medullaris using a surgical microscope, and detected the disseminated medulloblastoma cells floating in the cerebrospinal fluid using a compact fluorescence microscope. Furthermore, we performed PDT to the resected lumbar lesion with the adjuvant platinum-based chemotherapy, and the patient survived a meaningful life for more than 2 years after the lumbar surgery. This report describes the first case of a human patient in whom the efficacy of PD and PDT was demonstrated for a malignant spinal cord tumor. [ABSTRACT FROM AUTHOR]

Molecular fluorescence-guided surgery has shown promise for tumor margin delineation but is limited by its depth profiling capability. Interestingly, most fluorophores, either clinically approved or in clinical trials, can also be used as photoacoustic contrast agents, yet their use is limited due to the low light fluence permitted for clinical use and the limited sensitivity of current photoacoustic imaging systems. There is therefore an urgent unmet need to establish methods for enhancing contrast in molecular targeted PA imaging which could potentially complement and overcome limitations in molecular fluorescence guided therapies. In this study, we compare the photoacoustic (PA) and fluorescence imaging capabilities of a cetuximab-IRDye800 conjugate in a subcutaneous tumor xenograft model. We demonstrate that while the fluorescence signal increases steadily over time after administration of cetuximab-IRDye800, PA signal peaks early (~2 fold higher at 6-hour as compared to pre-injection controls) and then decreases (~1.3 fold higher at 24-hour as compared to pre-injection controls). This pattern aligns with previous findings using other antibody-conjugated PA contrast agents. Mechanistically, we demonstrate that the formation of H-aggregates upon antibody conjugation enhances PA contrast of the IRDye800. The disruption of these H-aggregates, as the antibody-dye conjugate is degraded post receptor-mediated endocytosis, decreases PA signal intensity. The timeframe of maximum PA signal and decrease thereafter is consistent with the time frame of receptor-mediated endocytosis of cetuximab-IRDye800. Our data suggests that tumor cell surface binding results in peak PA signal while lysosomal localization and degradation results in a significant drop in PA signal. Our study sheds light on the distinct temporal dynamics of PA and fluorescence signals of Cetuximab-IRDye800 conjugate and we propose that optimizing IRDye800 conjugation to antibodies can further enhance PA signal intensity when timed to precisely to capture IRDye800 in an H-aggregate form., Competing Interests: Conflict of interest: The authors declare that they have no conflict of interest

Bladder carcinoma in situ (CIS) is a potentially invasive tumor whose early detection is a key step to ensuring the preservation of the bladder, reducing mortality, and improving the quality of patients' life. The early diagnosis of bladder cancer requires a sensitive technique that can detect the lesion to determine its stage and grade. ALA induced-PpIX makes it possible to detect tumors with 90% sensitivity. ALA hexyl ester (hALA) increases the sensitivity to 95%. Macroscopic techniques require a histological biopsy to define the tumor invasiveness. Imaging with Fibered Optic Confocal Fluorescence Microscopy allows the optical sectioning of examined tissues providing images with subcellular resolution after labeling with adequate fluorescent dye chosen based on the sensitivity of the used device. Available fluorescent agents are compatible with used devices; however, their toxicity and mutagenesis studies are unsatisfactory. During imaging, an optical fiber is introduced into the bladder via the urethra and placed in contact with the bladder wall. The distinction between the different types of epithelial cells is based on the cell size, morphology, and signal intensity. Although not fully adopted for clinical application, the FOCM represents a real asset that reduces invasiveness and complements the fluorescence-based endoscopy. [ABSTRACT FROM AUTHOR]

Previous studies have found that use of hexaminolevulinate (HAL) and blue light cystoscopy (BLC) during treatment of bladder cancer had a positive impact on overall survival after later cystectomy, indicating a potential treatment effect beyond improved diagnostic accuracy. The aim of our study was to determine whether HAL and BL mimicking clinically relevant doses in an orthotopic rat model could have therapeutic effect by inducing modulation of a tumor-specific immune response. We also assessed whether administration with a checkpoint inhibitor could potentiate any effects observed. Rats were subjected to HAL BL alone and in combination with anti-PD-L1 and assessed for anti-tumor effects and effects on immune markers. Positive anti-tumor effect was observed in 63% and 31% of rats after, respectively, 12 and 30 days after the procedure, together with a localization effect of CD3+ and CD8+ cells after 30 days. Anti-tumor effect at 30 days increases from 31% up to 38% when combined with intravesical anti-PD-L1. In conclusion, our study demonstrated treatment effects with indications of systemic immune activation at diagnostic doses of HAL and blue light. The observed treatment effect seemed to be enhanced when used in combination with intravesically administrated immune checkpoint inhibitor. [ABSTRACT FROM AUTHOR]

5‐Aminolevulinic acid‐based photodynamic therapy (ALA‐PDT) comprises photochemical and biological reactions, finally generating tumor destruction. Tumor selectivity of ALA‐PDT relies on the disturbed heme synthesis pathway in neoplastic cells. Tumor pretreatment with ALA induces two reactions: the first, self‐activation of the key enzyme porphobilinogen synthase and then protoporphyrin (PpIX) synthesis at low Fe++ availability. We emphasize that the toxic mechanism of ALA‐PDT triggered by 1O2 targets intracellular organelle destruction death pathways. PpIX fluorescence of tumors, particularly in glioblastoma, is used clinically for fluorescence guidance during neurosurgery. Targeting residual and metastatic cancer stem cells is a crucial challenge of ALA‐PDT, plausibly combined with other therapeutic modalities to encounter metastatic recurrences. We overview the different aspects of ALA‐PDT mechanism and future research and prospects. [ABSTRACT FROM AUTHOR]

[Display omitted] • FTIR/OPLS-DA models by transflectance for diagnostic of SARS-CoV-2 virus infection. • Detection of SARS-CoV-2 can be obtained in a few minutes of spectral evaluation. • Prediction of SARS-CoV-2 with 100 % sensitivity, specificity and accuracy. The Coronavirus Disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has required the search for sensitive, rapid, specific, and lower-cost diagnostic methods to meet the high demand. The gold standard method of laboratory diagnosis is real-time reverse transcription polymerase chain reaction (RT-PCR). However, this method is costly and results can take time. In the literature, several studies have already described the potential of Fourier transform infrared spectroscopy (FTIR) as a tool in the biomedical field, including the diagnosis of viral infections, while being fast and inexpensive. In view of this, the objective of this study was to develop an FTIR model for the diagnosis of COVID-19. For this analysis, all private clients who had performed a face-to-face collection at the Univates Clinical Analysis Laboratory (LAC Univates) within a period of six months were invited to participate. Data from clients who agreed to participate in the study were collected, as well as nasopharyngeal secretions and a saliva sample. For the development of models, the RT-PCR result of nasopharyngeal secretions was used as a reference method. Absorptions with high discrimination (p < 0.001) between GI (28 patients, RT-PCR test positive to SARS-CoV-2 virus) and GII (173 patients who did not have the virus detected in the test) were most relevant at 3512 cm−1, 3385 cm−1 and 1321 cm−1 after 2nd derivative data transformation. To carry out the diagnostic modeling, chemometrics via FTIR and Discriminant Analysis of Orthogonal Partial Least Squares (OPLS-DA) by salivary transflectance mode with one latent variable and one orthogonal signal correction component were used. The model generated predictions with 100 % sensitivity, specificity and accuracy. With the proposed model, in a single application of an individual's saliva in the FTIR equipment, results related to the detection of SARS-CoV-2 can be obtained in a few minutes of spectral evaluation. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) is involved in the regulation of physiological and pathological mechanisms of the cardiovascular, nervous and immune systems; and plays an important role in cancer being involved in tumor growth and suppressing processes depending on its concentration. The development of a near-infrared excitable nanoprobe, consisting of gold nanoparticles functionalized with a two-photon excitable NO probe, for the detection of intracellular NO is reported. The nanoprobe showed good selectivity towards NO over cellular interferences and excellent stability in aqueous-medium over time. The nanoprobe was able to selectively detect endogenous and exogenous NO in different cell lines and it accumulated in the acidic organelles showing negligible toxicity. Importantly, the nanoprobe showed potential to quantify intracellular NO concentrations in breast cancer cells. The novel gold-based two-photon nanoprobe showed an excellent performance and versatility and could potentially be applied for the spatiotemporal monitoring of in vivo NO levels. [ABSTRACT FROM AUTHOR]

• Detectability of CIS varies depending on the endoscopic equipment used for PDD-TURBT. • Differences in endoscopic equipment may affect RFS and recurrence frequency. • Detection of CIS leads to appropriate selection of postoperative adjuvant therapy. Photodynamic diagnosis-assisted transurethral resection of bladder tumor (PDD-TURBT) for nonmuscle-invasive bladder cancer is superior to conventional white-light TURBT for cancer detection. However, when performing PDD-TURBT, cystoscopy findings vary depending on the quality of the endoscopic equipment. In this study, we compared the effects of different types of endoscopic equipment on postoperative outcomes. Patients who underwent their first PDD-TURBT at our clinic were selected. Patients on whom PDD-TURBT was performed using endoscopic equipment A were sorted into Group A, and patients on whom PDD-TURBT was performed using equipment S were sorted into Group S. The characteristics, recurrence-free survival (RFS), and recurrence frequency of these patients were retrospectively investigated and compared. The prognostic factors for RFS were also analyzed. A total of 49 patients were included in Group A and 46 in Group S. In Group S, a higher detection rate (8.2% vs. 30.4 %, p < 0.01) of carcinoma in situ (CIS) was noted. RFS tended to be better in Group S (HR 0.63, p = 0.15). The frequency of recurrence also tended to be lower in Group S (4.92 vs. 3.66 per 10,000 person-days, p = 0.08). Furthermore, CIS (HR 0.30, p = 0.04) and Bacillus Calmette–Guerin therapy (HR: 0.26, p = 0.01) were significant favorable prognostic factors for RFS. The quality of the endoscopic equipment may influence postoperative recurrence after PDD-TURBT. Higher-quality endoscopic instruments have superior CIS detection capabilities, which can lead to improvements in postoperative outcomes with the appropriate selection of postoperative adjuvant therapy. [ABSTRACT FROM AUTHOR]

Previous studies have found that use of hexaminolevulinate (HAL) and blue light cystoscopy (BLC) during treatment of bladder cancer had a positive impact on overall survival after later cystectomy, indicating a potential treatment effect beyond improved diagnostic accuracy. The aim of our study was to determine whether HAL and BL mimicking clinically relevant doses in an orthotopic rat model could have therapeutic effect by inducing modulation of a tumor-specific immune response. We also assessed whether administration with a checkpoint inhibitor could potentiate any effects observed. Rats were subjected to HAL BL alone and in combination with anti-PD-L1 and assessed for anti-tumor effects and effects on immune markers. Positive anti-tumor effect was observed in 63% and 31% of rats after, respectively, 12 and 30 days after the procedure, together with a localization effect of CD3+ and CD8+ cells after 30 days. Anti-tumor effect at 30 days increases from 31% up to 38% when combined with intravesical anti-PD-L1. In conclusion, our study demonstrated treatment effects with indications of systemic immune activation at diagnostic doses of HAL and blue light. The observed treatment effect seemed to be enhanced when used in combination with intravesically administrated immune checkpoint inhibitor.

Objective: The aim of this study was to demonstrate the clinical feasibility of intraoperative photodiagnosis (PD) of malignant brain tumor using talaporfin sodium (TPS), which is an agent used in photodynamic therapy (PDT) for cancers.Methods: Forty-seven patients diagnosed with malignant gliomas by preoperative imaging (42 patients with gliomas and 5 patients with other brain tumors) received an intravenous injection of TPS at 40 mg/m2 24 h before resection. During surgery, these patients were irradiated with diode laser light at 664 nm, and tumor fluorescence was observed. The fluorescence intensity was visually rated on a 3-point rating scale [strong fluorescence, weak fluorescence and no fluorescence]. TPS concentrations in 124 samples from 47 cases were measured by HPLC (High performance liquid chromatography).Results: The fluorescence intensity was confirmed to be weak in all patients with Grade II gliomas and strong in almost all patients with Grade III or IV gliomas, reflecting the histological grade of malignancy. In patients with non-glioma brain tumors except for 1 patient with a metastatic brain tumor, the fluorescence intensity was strong. The mean TPS concentration in tissues was 1.62 μg/g for strong fluorescence areas, 0.67 μg/g for weak fluorescence areas and 0.19 μg/g for no fluorescence areas.Conclusions: Establishment of an appropriate fluorescence observation system enabled fluorescence-guided resection of malignant brain tumors using TPS, and the fluorescence intensity of tumors correlated with the TPS concentrations in tissues. These results suggest that TPS is a useful photosensitizer for both intraoperative fluorescence diagnosis and photodynamic therapy.

• The Quantum Dots-Folic Acid conjugates are selective to KB cells. • Targeting ability of folic acid quantum dots was confirmed in 3D spheroid model. • The penetration profile for both types of quantum dots were similar in spheroids. • The crucial role of FRα receptor as a target was confirmed in vitro. Quantum dots (QDs) bring new insights in cancer theranostics. Exceptional brightness together with the simple possibility to modify surface with targeting molecules make QDs attractive agents in fluorescence guided surgery and photodynamic therapy. Currently, many targeted QDs have been developed for theranostic purpose. However, their targeting ability was tested mainly in two dimensional monolayer tumor cell models, while our study includes 3D tumor model reflecting the specificity of in vivo tumor environment. Core/multilayer shell CdSe/CdS/ZnS QDs were conjugated with folic acid (FA) and characterized spectroscopically. Cytotoxicity of QDs on KB and A549 cells lines were evaluated using the MTT assay. Cellular uptake of QDs was assessed by epifluorescent microscopy. To study the distribution of QDs in tumor tissue, KB spheroids were prepared by means of the liquid overlay technique and then frozen cut of spheroids treated with QDs were imaged by epifluorescence microscopy. We confirmed the specificity of QD-FA for the folic acid receptor positive KB cells. In 3D tumor spheroid model we demonstrated uptake enhancement of QD-FA compared with non-targeted QD. It was demonstrated that penetration profiles were similar for both QDs with penetration depth never exceeding 100 μm. We have demonstrated the effectiveness of FA conjugated QDs to target tumor spheroids thus confirming the crucial role of FRα receptor as a target. Further improvement of QD-FA targeting ability could be performed using dual targeting different targeting agents, such as FA and cyclic RGD. [ABSTRACT FROM AUTHOR]

In the pursuit of new potent photosensitizers (PSs) for photodynamic therapy (PDT) with better efficacy, a series of 5,15-diaryltetranaphtho [2,3]porphyrins (Ar 2 TNPs) with two or four carboxyalkoxy groups were designed, synthesized, and evaluated. These new compounds exhibited strong, broad and red-shifted UV–vis absorptions at 729 nm and other strong absorptions at 446, 475, 650, 659, 714 nm for tumors and other diseases of varying sizes and depths. They possess high molar extinction coefficients (0.95 × 105–1.48 × 105 M−1 cm−1), good singlet oxygen quantum yields and photodynamic antitumor effects towards Eca-109 cells in vitro. It is suggested that the extension of porphyrin with naphthalene into Ar 2 TNP results into remarkable improvement of photophysical characteristics, while the introduction of carboxyalkoxy groups on meso -phenyl can significantly improve the solubility and photodynamic effects in vitro and in vivo. Notably, compound II 3 can localize primarily in lysosomes of Eca-109 cells and induce substantial cell apoptosis after PDT. It can also selectively accumulate in tumor tissues and be traced real-timely through in vivo fluorescence imaging with distinctive inhibition of tumor growth. Therefore, compound II 3 deserves to be considered as a promising PDT drug candidate for individualized tumor real-time tracing and treatment. [Display omitted] • A series of 5,15-diaryltetranaphtho [2,3]porphyrins were designed and synthesized. • They exhibited red-shifted UV–vis absorptions and high molar extinction coefficients. • Compound II 3 showed stronger antitumor activity in vivo than Verteporfin. • II 3 selectively accumulated at the tumor site traced by in vivo fluorescence imaging. [ABSTRACT FROM AUTHOR]

Cutaneous leishmaniasis (CL) is a polymorphic and spectral skin disease caused by Leishmania spp. protozoan parasites. CL is difficult to diagnose because conventional methods are time-consuming, expensive, and low-sensitive. Fourier transform infrared spectroscopy (FTIR) with machine learning (ML) algorithms has been explored as an alternative to achieve fast and accurate results for many disease diagnoses. Besides the high accuracy demonstrated in numerous studies, the spectral variations between infected and noninfected groups are too subtle to be noticed. Since variability in sample set characteristics (such as sex, age, and diet) often leads to significant data variance and limits the comprehensive understanding of spectral characteristics and immune responses, we investigate a novel methodology for diagnosing CL in an animal model study. Blood serum, skin lesions, and draining popliteal lymph node samples were collected from Leishmania ( Leishmania ) amazonensis -infected BALB/C mice under experimental conditions. The FTIR method and ML algorithms accurately differentiated between infected (CL group) and noninfected (control group) samples. The best overall accuracy (∼72%) was obtained in an external validation test using principal component analysis and support vector machine algorithms in the 1800-700 cm -1 range for blood serum samples. The accuracy achieved in analyzing skin lesions and popliteal lymph node samples was satisfactory; however, notable disparities emerged in the validation tests compared to results obtained from blood samples. This discrepancy is likely attributed to the elevated sample variability resulting from molecular compositional differences. According to the findings, the successful functioning of prediction models is mainly related to data analysis rather than the differences in the molecular composition of the samples.

Summary Background Medulloblastoma (MB) is the most common malignant primary brain tumor of childhood. High risk patients still have a poor outcome, and especially young patients suffer from standard therapy induced sequelae. Therefore, other therapeutic options need to be explored. In glioblastoma (GBM), application of 5-aminolaevulinic acid (5-ALA) results in selective accumulation of protoporphyrin IX (PPIX) in the tumor cells, which can be exploited during fluorescence-guided surgery to increase the extent of resection or for photodynamic therapy (PDT) induced phototoxicity. It is not entirely clear, whether MB cells accumulate PPIX and are sensitive to PDT. Methods Human MYC -amplified (Med8A and D283) and non-amplified (UW228–2 and ONS76) MB cell lines were incubated for 2, 4 or 6 h with increasing doses (0–100 μg/ml) of 5-ALA, and PPIX accumulation was determined by flow cytometry. To assess sensitivity to 5-ALA/PDT, cells were incubated with 5-ALA and subsequently exposed to laser light of 635 nm wavelength (18.75 J/cm2). After an additional 24 h culture period, viability of cells was quantified using the WST-1 assay. Expression of ferrochelatase was detected by reverse transcription and quantitative polymerase chain reaction. Ferrochelatase activity was quantified by measuring the enzymatic conversion of PPIX to zinc-protoporphyrin. Expression of the ABCG2 transporter protein CD338 was detected by flow cytometry. Results All MB cell lines showed a time- and dose-dependent accumulation of PPIX after exposure to exogenous 5-ALA and became sensitive to 5-ALA/PDT-induced phototoxicity. PPIX accumulation was reduced compared to U373 GBM cells at shorter incubation periods and limiting 5-ALA doses. Moreover, not all MB cells became PPIX positive and overall phototoxicity was lower in the MB cell lines. Notably, the MYC -amplified MB cells demonstrated a more pronounced photosensitivity compared to their non-amplified counterparts. There was no difference in expression of ferrochelatase, but enzymatic activity appeared to be reduced in the MB cells compared to U373 GBM cells, whereas CD338 was expressed on the MB cells only. Conclusion Medulloblastoma cell lines accumulate PPIX after application of 5-ALA and become sensitive to PDT, associated with low ferrochelatase expression and activity. Photosensitivity is more pronounced in MYC -amplified cell lines. In contrast to GBM cells, however, PPIX accumulation appears to be reduced, restricted to a subset of cells and associated with lower photosensitivity of the MB cell lines, possibly due to expression of the ABCG2 transporter protein CD338 on MB cells. [ABSTRACT FROM AUTHOR]

Highlights • Human papillomaviruses (HPV) are the most common sexually-transmitted virus. • Carcinogenic HPV strains cause virtually all cervical cancer and precursor lesions. • HPV-related diseases have relevant impact in patient welfare and public healthcare. • This report collects data concerning HPV-induced lesions management and challenges. Abstract Human papillomaviruses (HPV) are the most common sexually-transmitted virus, and carcinogenic HPV strains are reported to be responsible for virtually all cases of cervical cancer and its precursor, the cervical intraepithelial neoplasia (CIN). About 30% of the sexually active population are considered to be affected by HPV. Around 600 million people are estimated to be infected worldwide. Diseases related to HPV cause significant impact from both the personal welfare point of view and public healthcare perspective. This resource letter collects relevant information regarding HPV-induced lesions and discusses both diagnosis and treatment, with particular attention to optical techniques and the challenges involved to the implementation of those approaches. [ABSTRACT FROM AUTHOR]

Treatment of cancer cells by clinically approved hexyl ester of 5-aminolevulinic acid (ALA-Hex) induces accumulation of fluorescent porphyrins in tumors. This allows fluorescence photodiagnosis (PD) of bladder cancer by blue light illumination. However, PD of other cancers is hampered by acute toxicity of the compound limiting its use to local applications. We have designed and synthesized a new prodrug of ALA-Hex that tackles the stability-activity paradox of amino-modified 5-ALA prodrugs. The glucuronide prodrug Glu-ALA-Hex demonstrates excellent stability under physiological conditions and activation in the presence of the target enzyme. β-glucuronidase-triggered release of 5-ALA is programmed to yield fluorescence in tumor environment with elevated β-glucuronidase activity, a characteristic of many solid tumors. Glu-ALA-Hex produces similar levels of fluorescence as ALA-Hex in breast cancer MCF7 cells in vitro but with much lower non-specific cell toxicity. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is an evolving method of treating superficial tumours that is non-invasive and carries minimal risk of toxicity. It combines tumour-selective photosensitiser dyes, tissue oxygen and targeted illumination to generate cytotoxic reactive oxygen species (ROS) within the tumour. In addition to directly acting on tumour cells, PDT damages and restricts tumour microvasculature, and causes a local inflammatory response that stimulates an immune response against the tumour. Unlike surgery or radiotherapy, the surrounding extracellular matrix is unaffected by PDT; thus, tissue healing is excellent and PDT seldom causes scars. This, combined with the ease of light application, has made PDT a popular treatment for cancers and pre-cancerous conditions in human beings. Moreover, because photosensitiser dyes are fluorescent and selectively accumulate in tumour tissues, they can additionally be used to visualise and discriminate tumour from normal tissues, thereby improving the accuracy of tumour surgery. In veterinary practice, PDT has been used successfully for treatment of superficial squamous cell carcinomas of the feline nasal planum; urinary tract, urinary bladder and prostate neoplasia in dogs; and equine sarcoids. The purpose of this article is to provide a comparative review of the current literature on PDT in human and veterinary medicine, and to establish a basis for future development of PDT in veterinary medicine. [ABSTRACT FROM AUTHOR]

Background The use of ALA to identify the parathyroid glands had been investigated both experimentally and clinically with promising results but the side effects from the systemic use of this photosensitizer reduce its widespread in clinical use. The aim of this study is to test the formulation of ALA in nano-stealth liposomes for better photodiagnosis of parathyroid glands intraoperatively with less ALA dose. Materials and Methods: Preparation of ALA nanovesicles and in vitro characterization for the drug encapsulation percentage, vesicle size and Zeta potential then the study of nanovesicles stability and in vitro drug release profile was done. The study compared nano-stealth liposomes and nano-liposomes with the free ALA solution, intraperitoneal administration of these different ALA formulations in rats and observing the ability to identify parathyroids intraoperatively and evaluation of fluorescence differences between these groups. Results and conclusion: Stealth liposomes were insignificantly higher in drug encapsulation%, in vitro drug release and zeta potential compared to conventional liposomes. Additionally, they needed less time for the start of the photosensitization and recorded the highest signal after spectrometry compared to the other two preparations. These data provide a new evidence of the potentiality of ALA-stealth Liposomes for identification of PTGs intraoperatively and could lead to propose a non-invasive procedure with reduced postoperative side effects. [ABSTRACT FROM AUTHOR]

Metabolic alterations of oral epithelial cells under oxidative stress are important signatures for early diagnosis of oral cancer. Amongst different metabolic alterations, non-invasive photo-diagnostic methods have been extensively used for determining cellular heme metabolism and accumulation of protoporphyrin IX (PpIX) under administration of suitable photosensitizer. In this study, we report these metabolic alterations by direct analysis of oral exfoliated cells obtained from individuals with prolonged smoking habit without the exogenous administration of any photosensitizer. The relative expression level of relevant biomolecules of study groups were compared with clinically diagnosed and histopathologically confirmed leukoplakia (OLPK) and oral squamous cell carcinoma (OSCC) patients. The energy imbalance and variation in ‘redox ratio’ were examined through spectroscopic studies which showed an increasing trend (p < 0.001) in smokers to OSCC groups in comparison to nonsmoker control. Gene expression of important intermediates of the heme metabolic pathway ( viz . 5-aminolevulinate synthase 1 (ALAS1), Ferrochelatase (FECH), hemeoxygenase 1 (HO-1) and ATP binding cassette subfamily G member 2 (ABCG2)) which affect production of PpIX was assessed. Relative mRNA level of ALAS1 and HO1 was upregulated whereas mRNA level of other genes ( viz . FECH and ABCG2) were found to be downregulated in smokers as well as in cancer groups. Outcome of different spectroscopic studies on exfoliated cells ( viz . fluorescence, atomic absorption and Fourier transform infrared spectroscopy) corroborated with the expression of biomarkers related to cellular endogenous metabolism related to heme cycle. This study indicates significant alterations in endogenous metabolic products, and cellular functional groups in oral epithelial cells among the study groups. Our study reports a strong possibility of diagnosis of early cancer signatures amongst habitual smokers by direct and non-invasive assessment of metabolic status of oral epithelial cells without exogenous administration of photosensitizers. The knowledge accrued from the study may guide clinicians in precise detection of precancer trend in the susceptible population through a noninvasive rapid screening method. [ABSTRACT FROM AUTHOR]

Bovine brucellosis diagnosis is a major problem to be solved; the disease has a tremendous economic impact with significant losses in meat and dairy products, besides the fact that it can be transmitted to humans. The sanitary measures instituted in Brazil are based on disease control through diagnosis, animal sacrifice, and vaccination. Although the currently available diagnostic tests show suitable quality parameters, they are time-consuming, and the incidence of false-positive and/or false-negative results is still observed, hindering effective disease control. The development of a low-cost, fast, and accurate brucellosis diagnosis test remains a need for proper sanitary measures at a large-scale analysis. In this context, spectroscopy techniques associated with machine learning tools have shown great potential for use in diagnostic tests. In this study, bovine blood serum was investigated by UV–vis spectroscopy and machine learning algorithms to build a prediction model for Brucella abortus diagnosis. Here we first pre-treated the UV raw data by using Standard Normal Deviate method to remove baseline deviation, then apply principal component analysis – a clustering method - to observe the group formation tendency; the first results showed no clustering tendency with a messy sample score distribution, then we properly select the main principal components to improve clusterization. Finally, by using machine learning algorithms (SVM and KNN), the predicting models achieved a 92.5% overall accuracy. The present methodology provides a test result in an average time of 5 min, while the standard diagnosis, with the screening and confirmatory tests, can take up to 48 h. The present result demonstrates the method's viability for diagnosing bovine brucellosis, which can significantly contribute to disease control programs in Brazil and other countries. [Display omitted] • Feature Selection Recursive Feature Elimination (RFE) algorithm enabled the elimination of usual PCs with high data variance. • The method can provide a test result in an average time of 5 min, while the standard diagnosis can take up to 48 h. • Methodology proposed (UV–Vis + ML) identified antibodies against B. abortus in cattle with 92.5% overall accuracy. [ABSTRACT FROM AUTHOR]

This paper evaluates how effectively chloroaluminum phthalocyanine (ClAlPc) entrapped in colloidal nanocarriers, such as nanocapsule (NC) and nanoemulsion (NE), induces photodamage in human prostate cancer cells (LNCaP) during photodynamic therapy (PDT). The MTT cell viability assay showed that both ClAlPc-NC and ClAlPc-NE induced phototoxicity and efficiently killed LNCaP cells at low ClAlPc-NC and ClAlPc-NE concentrations (0.3 μg mL −1 ) as well as under low light doses of 4 J cm −2 and 7 J cm −2 , respectively, upon PDT with a 670-nm diode laser line. Confocal imaging studies indicated that ClAlPc-NC and ClAlPc-NE were preferentially localized in the perinuclear region of LNCaP cells both in the dark and upon irradiation with laser light. After PDT treatment, ClAlPc-NC-treated LNCaP cells exhibited a higher green fluorescence signal, possibly due to the larger shrinkage of the actin cytoskeleton, compared to ClAlPc-NE-treated LNCaP cells. Additionally, ClAlPc-NC or ClAlPc-NE and mitochondria showed a relatively high co-localization level. The cellular morphology did not change in the dark, but confocal micrographs recorded after PDT revealed that LNCaP cells treated with ClAlPc-NC or ClAlPc-NE underwent morphological alterations. Our preliminary in vitro studies reinforced the hypothesis that biocompatible theranostic ClAlPc-loaded nanocarriers could act as an attractive photosensitizer system in PDT and could serve as an interesting molecular probe for the early diagnosis of prostate cancer and other carcinomas. [ABSTRACT FROM AUTHOR]

• Photodynamic diagnosis (PDD)-TURBT contributes to lower recurrence rates. • Intravesical BCG therapy with PDD-TURBT significantly improves recurrence free survival (RFS). • Tumor resection by PDD-TURBT may have a positive impact on subsequent BCG therapy. Intravesical Bacille Calmette–Guerin (BCG) therapy has been reported to be effective in preventing recurrence and progression in non-muscle invasive bladder cancer. Furthermore, photodynamic diagnosis (PDD)-assisted transurethral resection of bladder tumor (TURBT) improves the accuracy of cancer diagnosis and contributes to lower recurrence rates. The purpose of this study is to investigate whether more tumor resection with PDD-TURBT rather than conventional TURBT before BCG therapy outweighs the benefit of BCG therapy alone. Patients who underwent intravesical BCG therapy following TURBT in our institution from 2010 to 2021 were included. They were divided into the following two groups: those who received PDD-TURBT before BCG treatment (PDD + BCG group) and those who received conventional TURBT before BCG treatment (WL + BCG group). The 2-year recurrence-free survival (RFS) and progression-free survival (PFS) of the two groups were retrospectively analyzed and compared. The 2-year RFS was significantly improved in the PDD + BCG group (hazard ratio [HR]: 2.41, 95% confidence interval [CI]: 1.26–4.60; p = 0.025). No significant difference in 2-year PFS was noted between the two groups. Analysis of prognostic factors for RFS showed that PDD-TURBT w We think that this text does not adequately express the meaning that we want to deliver to the reader.as a significant prognostic factor in univariate analysis (HR: 0.41, 95% CI: 0.18–0.92; p = 0.03). BCG treatment following PDD-TURBT significantly improved RFS more than BCG therapy following WL-TURBT. More accurate tumor localization and more efficient tumor resection by PDD-TURBT may have a positive impact on subsequent BCG treatments even if the treatment is administered postoperatively. [ABSTRACT FROM AUTHOR]

• ALA-mediated accumulation of protoporphyrin appears to be greater in older bladder tumour cells. • This effect is correlated with the presence of an outward transport process mediated by a carrier termed ABCG2. • It is proposed that inhibition of this outward transport process could promote efficacy of ALA-PDT in cell types that express higher levels of ABCG2. Aminolevulinic acid-photodynamic diagnosis (ALA-PDD) is a promising alternative method to detect cancer cells because of its high specificity and low rate of side effects. Exogenous ALA is administered and accumulates as protoporphyrin IX (PpIX) in cancer cells, which then emit red fluorescence following light irradiation to enable surgeons to accurately identify and remove cancerous tissue. Recent reports suggested that PpIX failed to accumulate in some patients who underwent ALA-PDD. We hypothesized that cell senescence, which is a relatively inactive state, affects porphyrin accumulation in bladder cancer cells. In this study, we evaluated the relationship between cell senescence and porphyrin accumulation in affecting the efficacy of ALA-PDD. First, we utilized three bladder cancer cell lines to evaluate senescence-related indicators and establish a cell senescence model. Then, we identified the differences in porphyrin production and the proteins involved in porphyrin accumulation between old and young cells. We found that compared with young cells, old cells possessed higher concentration of PpIX and had lower ABCG2 expression. The increase in PpIX levels following ABCG2 inhibition is three times higher in old cells than in young cells, suggesting that cell senescence was closely related with porphyrin accumulation in cancer. In conclusion, we found that the efficacy of ALA-PDD and porphyrin accumulation was relatively high in senescent cancer cells and that inhibition of ABCG2 could improve the efficacy of ALA-PDD in young bladder cancer cells. [ABSTRACT FROM AUTHOR]

The time- and spectral-resolved set-up for measurements of weak infrared luminescence of photosensitizers (PSs) and singlet oxygen using optical lightguides was used on skin of laboratory animals in vivo. Wistar rats with abdominal incisions treated by methylis aminolevulinitis (MAL) were used as a model. A control group of animals with abdominal incisions was also tested. Spectrally resolved fluorescence of the PS was acquired during the treatment from the same spot. The intensity and spectral profile of the fluorescence signal from the skin can be used to guide the detection setup to the investigated spots in the lesion. The rate of bleaching of Protoporphyrin IX band and appearance of a band of its photoproducts during the treatment can be characterized by the exposition ED, under which the latter becomes dominant feature in fluorescence spectrum. ED value differs statistically significantly between the normal skin and the lesion treated by MAL. No direct proportionality was found between the fluorescence signal and singlet oxygen production. Nevertheless, the strong fluorescence signal is necessary but not a sufficient condition for higher singlet oxygen production in vivo. ED value correlates rather well with production of singlet oxygen, but differently in lesion and normal skin. Lifetimes of singlet oxygen differ between spots outside and in the lesion. PS triplet state lifetimes exhibit weak difference between spots treated and untreated by MAL.

The photodynamic therapy (PDT) is an alternative technique that can be indicated for superficial basal cell carcinoma (sBCC), Bowen’s disease and actinic keratosis with high efficiency. The objective of this study is to present the importance of fluorescence imaging for PDT guidance and monitoring in real time. Confirming that the lesion is well prepared and the photosensitizer shows a homogenous distribution, the outcome after few PDT sessions will be positive and the recurrence should be lower. Our proposition in this study is use the widefield fluorescence imaging to evaluate the PDT protocol in situ and in real time for each lesion. This evaluation procedure is performed in two steps: first with the monitoring of the production of protoporphyrin IX (PpIX) induced by methyl aminolevulinate (MAL), an derivative of 5-aminolevulinic acid (ALA) and second with the detection of PpIX photobleaching after illumination. The fluorescence images provide information correlated with distinct clinical features and with the treatment outcome. Eight BCC lesions are presented and discussed in this study. Different fluorescence patterns of PpIX production and photobleaching could be correlated with the treatment response. The presented results show the potential of using widefield fluorescence imaging as a guidance tool to customized PDT.

Background Photodermatoses are typically investigated by analyzing the individual or combined effects of ultraviolet A ( UVA), ultraviolet B ( UVB), and visible light using light sources that simulate portions of the solar spectrum. Infrared radiation ( IRR), however, accounts for 53% of incident solar radiation, but its effects are not taken into account in standard phototest protocols. Aims The aim was to analyze the effects of IRR, alone and combined with UVA and visible light on solar urticaria lesions, with a distinction between infrared A ( IRA) and infrared B ( IRB). Methods We performed standard phototests with UVA and visible light in four patients with solar urticaria and also tested the effects after blocking IRB with a water filter. To analyze the direct effect of IRR, we performed phototests with IRA and IRB. Results Initial standard phototests that were all positive found the induction of erythema and whealing, while when IRR was blocked from the UVA and visible light sources, three of the patients developed no lesions, while the fourth developed a very small wheal. Conclusion These results suggest that IRR has the potential to produce and exacerbate lesions caused by other types of radiation. Consideration of these effects during phototesting could help prevent diagnostic errors. [ABSTRACT FROM AUTHOR]

Visible and near-infrared radiation is now widely employed in health science and technology. Pre-clinical trials are still essential to allow appropriate translation of optical methods into clinical practice. Our results stress the importance of considering the mouse strain and gender when planning pre-clinical experiments that depend on light–skin interactions. Here, we evaluated the optical properties of depilated albino and pigmented mouse skin using reproducible methods to determine parameters that have wide applicability in biomedical optics. Light penetration depth (δ), absorption (μ a ), reduced scattering (μ′ s ) and reduced attenuation (μ′ t ) coefficients were calculated using the Kubelka–Munk model of photon transport and spectrophotometric measurements. Within a broad wavelength coverage (400–1400 nm), the main optical tissue interactions of visible and near infrared radiation could be inferred. Histological analysis was performed to correlate the findings with tissue composition and structure. Disperse melanin granules present in depilated pigmented mouse skin were shown to be irrelevant for light absorption. Gender mostly affected optical properties in the visible range due to variations in blood and abundance of dense connective tissue. On the other hand, mouse strains could produce more variations in the hydration level of skin, leading to changes in absorption in the infrared spectral region. A spectral region of minimal light attenuation, commonly referred as the “optical window”, was observed between 600 and 1350 nm. [ABSTRACT FROM AUTHOR]

Objective This study investigated the efficacy and safety of a newly designed LED device used in photodiagnosis and photodynamic therapy of moderate to severe acne vulgaris in Chinese patients. Methods Forty-six patients with moderate to severe facial acne showing high degrees of fluorescence by ultraviolet light examination were illuminated during ALA-PDT with two wavelengths of light (543–548 nm, and 630 ± 6 nm, respectively) after 2 h of incubation with ALA. Each patient received treatment once every 30 days for two or three sessions. Two independent investigators assigned an acne severity score at baseline, one week after each treatment, as well as 4, 8, and 12 weeks after the completion of treatment. Adverse effects were recorded during and after each treatment. All patients rated their satisfaction with the results of treatment at a 12-week follow up visit. Results The ALA-PDL treatment regimen showed an overall effectiveness rate of 89.13% (41/46 patients). Some degree of clinical efficacy was seen in 71.42%, 86.67%, and 95.83% of patients with grades IV, V, and VI acne, respectively, and the rate of clinical effectiveness increased with increasing acne severity. When compared with baseline scores, significant reductions in acne scores were obtained at 8, and 12 weeks after completion of treatment. Maximum efficacy was shown at the 12 week follow up. No severe adverse events were observed. Conclusion ALA-PDT administered with the newly designed LED device was an effective treatment for moderate to severe acne vulgaris, and side effects were mild and reversible. [ABSTRACT FROM AUTHOR]

• Green fluorescent FA/HA-functionalized carbon dots (FA-CDs and HA-CDs) were prepared by one-step hydrothermal method and then amide reaction. • FA-CDs and HA-CDs had good water solubility, cytocompatibility, excellent fluorescence properties and targeted function, laying a foundation for their application in human breast cancer cells imaging. • FA-CDs and HA-CDs could accurately identified breast cancer cells and normal cells. Green fluorescent carbon dots (CDs) were prepared by one-step hydrothermal method and then modified into folic acid functionalized carbon dots (FA-CDs) and hyaluronic acid functionalized carbon dots (HA-CDs) with targeted function to study their application in breast cancer cells imaging. The microstructure of the CDs observed through TEM showed the CDs with a scale of 2.69 nm. FT-IR and XPS showed the changes of bonds and functional groups that confirmed the transformation of COOH and NH 2 to amide bonds. FA-CDs and HA-CDs had good water solubility and cytocompatibility, which laid a foundation for their application in human breast cancer cells imaging. At the same time, FA-CDs and HA-CDs had strong fluorescence excitation, and the optimal emission wavelength was about 450 nm. In fluorescence imaging of cells, carbon dots had bright green fluorescence in both breast cancer cells (MCF-7 cells) and normal cells (EC cells). After targeted endocytosis, FA-CDs and HA-CDs could emit bright green fluorescence in cancer cells but could not in normal cells, which proved that the synthesized FA-CDs and HA-CDs had targeting properties. FA-CDs and HA-CDs could be used to accurately identify breast cancer cells and normal cells as cancer diagnosis material, which had the potential application in early cancer diagnosis. [ABSTRACT FROM AUTHOR]

Non-invasive treatment monitoring is one of the key elements to assess the photosensitizer activation during the photochemical process underlying Photodynamic Therapy (TFD) by its fluorescence. Furthermore the photosensitizer fluorescence can be employed to discriminate the pathological tissue from the healthy one. In this work the superficial fluorescence patterns in three different types of nonmelanoma skin cancer tumors and their photodynamic treatment response are analysed by a fluorescence based dosimetric model for PDT with topical MAL-PpIX. Results show differences of even more than 50% in the fluorescence patterns as the treatment progresses depending on the malignant tissue type. They demonstrate the great relevance of the biological media as an additional dosimetric factor within the photodynamic context. These results contribute to the development of a future customized therapy with the assistance of dosimetric tools to interpret the fluorescence images obtained during the treatment monitoring as well as in differential photodiagnosis. [ABSTRACT FROM AUTHOR]

The time- and spectral-resolved set-up for measurements of weak infrared luminescence of photosensitizers (PSs) and singlet oxygen using optical lightguides was used on skin of laboratory animals in vivo. Wistar rats with abdominal incisions treated by methylis aminolevulinitis (MAL) were used as a model. A control group of animals with abdominal incisions was also tested. Spectrally resolved fluorescence of the PS was acquired during the treatment from the same spot. The intensity and spectral profile of the fluorescence signal from the skin can be used to guide the detection setup to the investigated spots in the lesion. The rate of bleaching of Protoporphyrin IX band and appearance of a band of its photoproducts during the treatment can be characterized by the exposition ED, under which the latter becomes dominant feature in fluorescence spectrum. ED value differs statistically significantly between the normal skin and the lesion treated by MAL. No direct proportionality was found between the fluorescence signal and singlet oxygen production. Nevertheless, the strong fluorescence signal is necessary but not a sufficient condition for higher singlet oxygen production in vivo. ED value correlates rather well with production of singlet oxygen, but differently in lesion and normal skin. Lifetimes of singlet oxygen differ between spots outside and in the lesion. PS triplet state lifetimes exhibit weak difference between spots treated and untreated by MAL. [ABSTRACT FROM AUTHOR]

Background Basal cell carcinoma ( BCC) is the most frequent malignant tumor of the skin. The high prevalence of BCC, the risk of local recurrence, and the difficult clinical identification of the excision margins emphasize the importance of studying new approaches, ensuring complete surgical excision that allows preservation of normal tissue, especially for BCCs located on cosmetically important areas such as the mid face. Photodiagnosis ( PD) is a pre-operative technique that allows a more accurate distinction of neoplastic lesions from surrounding healthy skin in vivo. Purpose The aim of this study is to assess the usefulness of PD for the evaluation of tumor margins in 10 patients with recurrent BCC of the face. Methods We study the red fluorescence emitted by neoplastic tissue under a Wood's lamp irradiation, after accumulation of methyl amino levulinate ( MAL) cream in 10 patients with recurrent BCC. Results Our histologic analysis of perilesional skin by PD allowed to delineate more precise tumor margins, thus achieving radical excision in 90% of patients. Conclusion PD represents a diagnostic method that helps to distinguish between tumor tissue and surrounding healthy tissue especially in case of recurrent BCC of the face when the clinical delimitation is not clear. [ABSTRACT FROM AUTHOR]

Paracoccidioidomycosis (PCM) is a systemic granulomatous mycosis endemic to Latin America, whose etiologic agents are fungi of the genus Paracoccidioides. PCM is usually diagnosed by microscopic observation of the fungus in biological samples, combined or not with other techniques such as serological methods. However, all currently used diagnostic methods have limitations. The objective of this study was to develop a method based on Fourier transform infrared spectroscopy (FTIR) and chemometric analysis for PCM diagnosis. We included 224 serum samples: 132 PCM sera, 24 aspergillosis sera, 10 cryptococcosis sera, 8 histoplasmosis sera, and 50 sera from healthy blood donors. Samples were analyzed by attenuated total reflection (ATR), and chemometric analyses including exploratory analysis through principal component analysis (PCA) and a classification method (PCM and non-PCM) through orthogonal partial least squares discriminant analysis (OPLS-DA). The spectra were similar, with the main bands up to approximately 1652 cm–1 and 1543 cm–1 (amide I and amide II bands). This same region was mainly responsible for the partial separation of the samples in PCA. The OPLS-DA model correctly classified all serum samples with only one latent variable, with a determination coefficient (R²) higher than 0.999 for both the calibration set and prediction set. Sensitivity and specificity were 100% for both sets, showing better performance than the reference diagnostic methods. Therefore, the use of FTIR/ATR together with OPLS-DA modeling proved to be a promising method for PCM diagnosis. • It is possible to diagnose paracoccidioidomycosis (PCM) using FTIR of serum. • Differences between sera from patients with PCM and other sera were explored. • The main differences are found in the protein regions. • The proposed chemometric diagnostic model showed high sensitivity and specificity. [ABSTRACT FROM AUTHOR]

This study investigated the ability of cholesterol-phosphatidylcholine liposomes loaded with chloride aluminum phthalocyanine (CL-AlClPc) to discriminate between healthy (MCF-10A) and neoplastic (MCF-7 and MDA-MB-231) breast cells for breast cancer diagnosis and treatment by photodynamic therapy (PDT) using a new drug delivery system consisting of CL-AlClPc. When PDT treatment was applied at an energy fluence of 700 mJ/cm², CL-AlClPc was more cytotoxic to neoplastic cells than to healthy breast cells because CL-AlClPc was better internalized by the tumor cells. An even higher fluorescence signal is expected for neoplastic cells during clinical treatment than for healthy cells, which will be useful for precise and targeted tumor cell detection. CL-AlClPc also facilitated better drug distribution and targeting of essential organelles inside the cells. This selectivity is critical for future in vivo diagnosis and treatment; it prevents side effects because it prioritizes tumor cells and tissues instead of healthy ones. The CL-AlClPc system designed herein had a small size (150 nm), low zeta potential (-6 mV), low polydispersity (0.16), high encapsulation rate efficiency (82.83%), and high shelf stability (12 months). [ABSTRACT FROM AUTHOR]

We conducted a prospective study to evaluate visualization of laryngeal lesions using AFE videoendoscopy, which is a new illumination system that allows for real-time WLE, but also makes it possible to switch to AFE endoscopy by the press of a single button. In total, 78 patients (53 men and 25 women) with signs or symptoms suggesting laryngeal dysfunction were included in this analysis. Histopathology revealed 30 cases (24%) of benign lesions such as granullomas, polyps, chronic laryngitis and papillomas. Mild dysplasia occurred in 35 cases (28%), moderate dysplasia in 18 cases (14.4%), severe dysplasia or carcinoma in situ in 32 cases (25.6%) and early invasive carcinoma in 10 cases (8%). Our results similar to other studies, have demonstrated a sensitivity by white light laryngoscopy of 88% and specificity of 77%. The sensitivity by autofluorescence laryngoscopy was 94% and specificity to 87%. The diagnosis accuracy by white light laryngoscopy was 73% (n=57) and that of autofluorescence 84% (n=66). Interest in fluorescence diagnostics in vivo has increased considerably in the last few years, as a result of several factors: the availability, decreasing cost and clinical suitability of the required technologies, development of new exogenous fluorophores and more detailed understanding of autofluorescence. [ABSTRACT FROM AUTHOR]

Summary Background Reduction of myocardial ischemia-reperfusion injury in the patients undergoing cardiac surgery under cardiopulmonary bypass represents an important goal. Intraoperative monitoring of myocardial metabolic state using continuous registration of nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) fluorescence might contribute to the solution of the problem. The successful application of fluorescent spectroscopy in the clinical field requires additional refinement of the technique, particularly using excitation of both NADH and FAD with different wavelengths. Methods The experiments were performed on the isolated Langendorff-perfused rat hearts ( n = 28) subjected to either regional or global ischemia-reperfusion. Two principles of NADH and FAD autofluorescence (AF) measurement were used for ischemia monitoring: (1) analysis of photographs and videos obtained with multispectral organoscopy technique allowing the assessment of both spatial and temporal characteristics of the process ( n = 16); (2) continuous registration of tissue redox state in a representative area of the heart by application of local spectroscopy, assisted by fiber optic spectrometer ( n = 12). Results It was found that regional myocardial ischemia resulted in a rapid, substantial increase in the intensity of NADH AF excited at 360 nm in the ischemic versus non-ischemic area of the heart. The same result was obtained when the heart was made globally ischemic, while the restoration of perfusate flow completely reversed the increase in NADH AF. During the transition from ischemia to reperfusion, the spatial heterogeneity of myocardial AF was noted on video recordings, probably reflecting the microheterogeneity of myocardial blood flow. Local spectroscopy studies demonstrated opposite changes in the NADH and FAD AF during ischemia. Using both methodological approaches, we found that repetitive brief episodes of global myocardial ischemia resulted in progressive decrease in the magnitude of AF elevation, which might point to preconditioning effect. Conclusions The application of multispectral fluorescent organoscopy offers the advantage of monitoring myocardial redox state at the level of the entire heart. Local spectroscopy is characterized by better precision and, in addition, provides the unique opportunity to measure AF in different parts of the spectrum. AF measurements are non-invasive, rapid, and technically easy to perform. For future clinical applications, it might be recommended to combine the measurement of redox state of both NADH and FAD, using excitation wavelength and emission filter optimal for each fluorophore. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) and photodiagnosis based on the intracellular production of the photosensitizer protoporphyrin IX (PPIX) by administration of its metabolic precursor δ-aminolevulinic acid (ALA) achieved their breakthrough upon the clinical approval of MAL (ALA methyl ester) and HAL (ALA hexyl ester). For newly developed ALA derivatives or application in new tumor types, in vitro determination of PPIX formation involves multiparametric experiments covering variable pro-drug concentrations, medium composition, time points of analysis, and cell type(s). This study uses a fluorescence microplate reader with a built-in temperature and atmosphere control to investigate the high-resolution long-term kinetics (72 h) of cellular PPIX fueled by administration of either ALA, MAL, or HAL for each 10 different concentrations. For simultaneous proliferation correction, A431 cells were stably transfected with green fluorescent protein. The results indicate that the peak PPIX level is a function of both, incubation concentration and period: maximal PPIX is generated with 1 to 2-mM ALA/MAL or 0.125-mM HAL; also, the PPIX peak shifts to longer incubation periods with increasing prodrug concentrations. The results underline the need for detailed temporal analysis of PPIX formation to optimize ALA (derivative)-based PDT or photodiagnosis and highlight the value of environment-controlled microplate readers for automated in vitro analysis. [ABSTRACT FROM AUTHOR]

Summary: Background: New treatment strategies for malignant gliomas are indispensible, due to the poor prognosis for patients. Fluorescence diagnosis (FD) and photodynamic therapy (PDT) are currently under intensive investigation and seem to improve the prognosis. Especially for deep seated malignant brain lesions and in order to optimize therapy new diagnostic tools are needed. Methods: In a syngeneic subcutaneous glioma mouse model we investigated the time dependent hypericin (HYP) uptake in malignant tumor tissue by microendoscopically fluorescence measurements. The HYP fluorescence in tumor was also detected by fluorescence microscopy (FM) and was compared to endoscopic data. Results: Both methods, microendoscopy and FM, demonstrated time dependent HYP uptake in subcutaneously implanted mouse glioma. Maximum of HYP uptake was achieved after 6h, measured with both methods. FM reached a 10-fold increase in fluorescence intensity compared to the autofluorescence. Measured by microendoscopy a 2.2-fold HYP fluorescence intensity compared to the autofluorescence was detected. Microendoscopy enables visualization of small vessels even in healthy brain tissue by intravascular HYP fluorescence. Conclusion: The new developed microendoscope enables not only fluorescence based discrimination of tumor and healthy tissue, but also semiquantitative measurements of fluorescence intensities in vivo. Individual repetitive fluorescence diagnosis will become possible by this method and opens up new possibilities for determining optimal settings of light applications for PDT. [Copyright &y& Elsevier]

This paper describes the elimination of porphyrins by feces. It was demonstrated that porphyrin accumulates substantially more in tumors than in normal tissues, and consequently more PPIX reaches the blood of patients and animals with tumors, and then, it needs to be eliminated. The fluorescence of feces revealed that there are large amounts of PPIX in the excreta of animals with cancer comparing with healthy animals. The autofluorescence of feces porphyrin extracted with acetone was analyzed using fluorescence spectroscopy of animals inoculated with DU145 cells into the prostate and healthy animals to monitor the PPIX concentration. Emission spectra were obtained by exciting the samples at 405 nm. Significant differences were observed in autofluorescence intensities measured in the 575-725 nm spectral regions for the studied groups. The results showed a noninvasive, simple, rapid and sensitive method to detect cancer by feces analysis. [ABSTRACT FROM AUTHOR]

Abstract: Aims: We aimed to demonstrate that Hypericin, a component of St. Johns Wort, selectively visualizes malignant gliomas. Hypericin is known as one of the most powerful photosensitizers in nature with excellent fluorescent properties. Methods: In five patients with a recurrence of a malignant glioma a newly developed water soluble formulation of hypericin was given intravenously (0.1 mg/kg body weight) 6 h before the surgical procedure. Tumor resection was performed under white light and fluorescence mode. The intensity grade of the tissue fluorescence was categorisized by the surgeon in three grades, highly fluorescent, weakly fluorescent and not fluorescent. In these areas tissue samples were taken and investigated by two blinded independent neuropathologists. Tissue samples were histologically classified differentiating between tumor tissue, tumor necrosis, tissue with scattered tumor cells and normal brain tissue. Results: In all patients tumor tissue was clearly distinguishable by its typically red fluorescence color from normal brain tissue which was colored blue under a special fluorescent filter. Histological evaluation of the 110 tissue samples showed a specificity of 100% and sensitivity of 91% for one of the two neuropathologists, whereas specificity for second pathologist was 90% and sensitivity 94%. The i.v. application of Hypericin proofed to be safe in all cases and there were no side effects observed. Conclusion: Hypericin in its water soluble form is a well tolerated drug. In addition to its high photosensitizing properties hypericin will open up interesting new therapeutic possibilities especially when used in combination with fluorescence detection and simultaneously photodynamic therapy. [Copyright &y& Elsevier]

Summary: Background: The objective of this study was to improve the feasibility of applying topic 5-aminolevulinic acid (ALA) in photodiagnosis (PD) and treatment of condyloma caused by human papillomavirus (HPV) using two homemade handheld devices and to discuss the photodynamic therapy (PDT) as a suitable alternative for each of the cases studied. Both, protoporphyrin IX production and photodegradation were analyzed, and the pain experienced during the illumination was correlated with the light intensities. Methods: A total of 40 women with different grades of lesions caused by HPV were chosen from patients of the School of Medicine of Ribeirão Preto (University of Sao Paulo) and of the Unit of Public Health of Araraquara, Sao Paulo. Results: We did not encounter any unexpected difficulties using our devices during the treatment. The existence of an easily observable reddish fluorescence with large intensity concentrated on the lesions is the clinical indication of the penetration and the selective concentration of protoporphyrin IX in the clinical and subclinical lesions rather than in the healthy tissue. The aesthetic results were much better than those obtained by conventional techniques as surgery or cryogenics, with no recurrence reported after two years of treatment. Conclusions: Our results are proof for the various advantages using ALA cream for the PD and PDT in many different cases of condyloma by HPV. This study will be continued to investigate the PpIX photobleaching and the irradiance and fluence rate to optimize conducting the clinical trials, to improve the devices and therefore increase the treatment response. [Copyright &y& Elsevier]