Optical techniques for the diagnosis and treatment of lesions induced by the human papillomavirus - A resource letter

Ultrasonic scalpel associated with photodynamic therapy in the treatment of refractory vulvar condyloma acuminatum

This is a case report of a patient with vulvar condyloma acuminatum associated with hyperkeratosis and folliculitis, which had been refractory to two previous therapies. The patient had been successfully treated using a combination of promising techniques: the ultrasonic scalpel and MAL photodynamic therapy.

Topical 5-Aminolevulinic Acid Photodynamic Therapy for Cervical High-Grade Squamous Intraepithelial Lesions

OBJECTIVE

To evaluate the efficacy of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in the treatment of high-grade squamous intraepithelial lesions of the cervix (HSIL).

METHODS

This retrospective study included 22 female patients with histologically confirmed HSIL and high-risk human papillomavirus (HR-HPV) infections. Patients were treated with ALA-PDT once a week for a total of 6 times. All patients had a follow-up period of 3 months and 6 months. The assessment of effectiveness of ALA-PDT was performed by ThinPrep cytology test (TCT), HPV DNA assay, HPV E6/E7 mRNA examination, colposcopy, biopsy, and immunohistochemistry detection.

RESULTS

Three months after 5-ALA PDT, the histologic disappearance rate was 81.82% (18/22), while the HPV clearance rate was 54.55% (12/22). At the 6 months checkpoint, the HSIL disappearance rate was 90.91% (20/22) and the HPV clearance rate was 86.36% (19/22). Before PDT, 68.18% of patients (15/22) were confirmed with TCT abnormalities, while only one patient (1/22, 4.55%) was abnormal in the TCT test at 6 months checkpoint. All participants were found HPV E6/E7 mRNA positive initially, while the HPV E6/E7 mRNA negative rate was 90.91% (20/22) at 6 months checkpoint. Additionally, we found a significant difference of the expression of CD4+ & CD8+ T cells and HPV E6 & E7 proteins before ALA-PDT and at 3 months follow-up (P < 0.01). No severe side effects were seen.

CONCLUSIONS

Topical 5-ALA PDT is an effective treatment for cervical HSIL with HR-HPV infection.

Photodynamic viral inactivation: Recent advances and potential applications

Antibiotic-resistant bacteria, which are growing at a frightening rate worldwide, has put the world on a long-standing alert. The COVID-19 health crisis reinforced the pressing need to address a fast-developing pandemic. To mitigate these health emergencies and prevent economic collapse, cheap, practical, and easily applicable infection control techniques are essential worldwide. Application of light in the form of photodynamic action on microorganisms and viruses has been growing and is now successfully applied in several areas. The efficacy of this approach has been demonstrated in the fight against viruses, prompting additional efforts to advance the technique, including safety use protocols. In particular, its application to suppress respiratory tract infections and to provide decontamination of fluids, such as blood plasma and others, can become an inexpensive alternative strategy in the fight against viral and bacterial infections. Diverse early treatment methods based on photodynamic action enable an accelerated response to emerging threats prior to the availability of preventative drugs. In this review, we evaluate a vast number of photodynamic demonstrations and first-principle proofs carried out on viral control, revealing its potential and encouraging its rapid development toward safe clinical practice. This review highlights the main research trends and, as a futuristic exercise, anticipates potential situations where photodynamic treatment can provide a readily available solution.

DNA Biosensor Based on Double-Layer Discharge for the Detection of HPV Type 16

DNA electrochemical biosensors represent a feasible alternative for the diagnosis of different pathologies. In this work, the development of an electrochemical method for Human Papillomavirus-16 (HPV-16) sensing is reported based on potential relaxation measurements related to the discharge of a complex double layer of a DNA-modified gold electrode. The method used allows us to propose an equivalent circuit (EC) for a DNA/Au electrode, which was corroborated by electrochemical impedance spectroscopy (EIS) measurement. This model differs from the Randles circuit that is commonly used in double-layer simulations. The change in the potential relaxation and associated charge transfer resistance were used for sensing the DNA hybridization by using the redox pair Fe(CN)₆^4-/Fe(CN)₆³⁺ as an electrochemical indicator. In order to determinate only the potential relaxation of the composed double layer, the faradic and double-layer current contributions were separated using a rectifier diode arrangement. A detection limit of 0.38 nM was obtained for the target HPV-16 DNA sequences. The biosensor showed a qualitative discrimination between a single-base mismatched sequence and the fully complementary HPV-16 DNA target. The results indicate that the discharge of the double-layer detection method can be used to develop an HPV DNA biosensor.

Nitrobenzene method: A keystone in meso-substituted halogenated porphyrin synthesis and applications

This review article briefly describes the available synthetic approaches for meso-arylporphyrins giving particular emphasis for one-pot nitrobenzene and nitrobenzene/NaY methods regarding the synthesis of meso-halogenated arylporphyrins. The review also describes the relevant applications of these halogenated porphyrins and their metalloporphyrin counterparts, prepared via nitrobenzene method, as photosensitizers for therapy (PDT and PDI), diagnostic (molecular contrast agents) and also for catalytic oxidation and CO2 cycloaddition reactions to epoxides.