A Narrative Review on Oral and Periodontal Bacteria Microbiota Photobiomodulation, through Visible and Near-Infrared Light: From the Origins to Modern Therapies.

Photobiomodulation (PBM) consists of a photon energy transfer to the cell, employing non-ionizing light sources belonging to the visible and infrared spectrum. PBM acts on some intrinsic properties of molecules, energizing them through specific light wavelengths. During the evolution of life, semiconducting minerals were energized by sun radiation. The molecules that followed became photoacceptors and were expressed into the first proto-cells and prokaryote membranes. Afterward, the components of the mitochondria electron transport chain influenced the eukaryotic cell physiology. Therefore, although many organisms have not utilized light as an energy source, many of the molecules involved in their physiology have retained their primordial photoacceptive properties. Thus, in this review, we discuss how PBM can affect the oral microbiota through photo-energization and the non-thermal effect of light on photoacceptors (i.e., cytochromes, flavins, and iron-proteins). Sometimes, the interaction of photons with pigments of an endogenous nature is followed by thermal or photodynamic-like effects. However, the preliminary data do not allow determining reliable therapies but stress the need for further knowledge on light-bacteria interactions and microbiota management in the health and illness of patients through PBM.

Progress of Phototherapy Applications in the Treatment of Bone Cancer.

Bone cancer including primary bone cancer and metastatic bone cancer, remains a challenge claiming millions of lives and affecting the life quality of survivors. Conventional treatments of bone cancer include wide surgical resection, radiotherapy, and chemotherapy. However, some bone cancer cells may remain or recur in the local area after resection, some are highly resistant to chemotherapy, and some are insensitive to radiotherapy. Phototherapy (PT) including photodynamic therapy (PDT) and photothermal therapy (PTT), is a clinically approved, minimally invasive, and highly selective treatment, and has been widely reported for cancer therapy. Under the irradiation of light of a specific wavelength, the photosensitizer (PS) in PDT can cause the increase of intracellular ROS and the photothermal agent (PTA) in PTT can induce photothermal conversion, leading to the tumoricidal effects. In this review, the progress of PT applications in the treatment of bone cancer has been outlined and summarized, and some envisioned challenges and future perspectives have been mentioned. This review provides the current state of the art regarding PDT and PTT in bone cancer and inspiration for future studies on PT.

Co-encapsulating indocyanine green and CT contrast agent within nanoliposomes for trimodal imaging and near infrared phototherapy of cancer.

X-ray CT imaging can be complementary to fluorescence and photoacoustic imaging (FLI and PAI), allowing for high spatial resolution and high-sensitivity multimodal imaging for imaging guided treatment. In this study, the CT contrast agent iohexol was co-encapsulated with indocyanine green (ICG) within nanoliposomes (NLs) to explore their interaction and possible application of this liposomal formulation (LGI) in cancer theranostics. The photophysical properties of LGI were studied to assess the effect of iohexol on ICG that can enhance the efficiency of ICG-based near infrared photodynamic therapy (PDT). The CT, FLI and PA imaging abilities of LGI were also investigated. Furthermore, the near infrared phototherapy of cancer cells in vitro was performed, exhibiting higher phototherapy efficacy of LGI in comparison with other ICG formulations. We conclude that LGI can serve as a highly efficient theranostic nanoplatform for multimodal (fluorescence, CT and PA) imaging and near infrared phototherapy.

Circadian Responses to Fragmented Light: Research Synopsis in Humans.

Light is the chief signal used by the human circadian pacemaker to maintain precise biological timekeeping. Though it has been historically assumed that light resets the pacemaker's rhythm in a dose-dependent fashion, a number of studies report enhanced circadian photosensitivity to the initial moments of light exposure, such that there are quickly diminishing returns on phase-shifting the longer the light is shown. In the current review, we summarize findings from a family of experiments conducted over two decades in the research wing of the Brigham and Women's Hospital that examined the human pacemaker's responses to standardized changes in light patterns generated from an overhead fluorescent ballast. Across several hundred days of laboratory recording, the research group observed phase-shifts in the body temperature and melatonin rhythms that scaled with illuminance. However, as suspected, phase resetting was optimized when exposure occurred as a series of minute-long episodes separated by periods of intervening darkness. These observations set the stage for a more recent program of study at Stanford University that evaluated whether the human pacemaker was capable of integrating fragmented bursts of light in much the same way it perceived steady luminance. The results here suggest that ultra-short durations of light-lasting just 1-2 seconds in total-can elicit pacemaker responses rivaling those created by continuous hour-long stimulation if those few seconds of light are evenly distributed across the hour as discreet 2-millisecond pulses. We conclude our review with a brief discussion of these findings and their potential application in future phototherapy techniques.

A Review on the Scope of Photothermal Therapy-Based Nanomedicines in Preclinical Models of Colorectal Cancer.

Oncologic thermal ablation involves the use of hyperthermic temperatures to damage and treat solid cancers. Thermal ablation is being investigated as a method of treatment in colorectal cancers and has the potential to complement conventional anticancer treatments in managing local recurrence and metastatic disease. Photothermal therapy utilizes photosensitive agents to generate local heat and induce thermal ablation. There is growing interest in developing nanotechnology platforms to deliver such photosensitive agents. An advantage of nanomedicines is their multifunctionality, with the capability to deliver combinations of chemotherapeutics and cancer-imaging agents. To date, there have been no clinical studies evaluating photothermal therapy-based nanomedicines in colorectal cancers. This review presents the current scope of preclinical studies, investigating nanomedicines that have been developed for delivering multimodal photothermal therapy to colorectal cancers, with an emphasis on potential clinical applications.

Complications of laser and light-based devices therapy in patients with skin of color.

Lasers and light-based devices are indispensable to an aesthetic dermatology practice. The growing popularity of lasers has been matched by a sharp increase in the incidence of complications. The Indian skin with its high melanin content is more prone to injury and careful setting of laser parameters, early detection of complications and immediate therapy are vital to avoiding permanent sequelae. We review the various complications that occur during laser procedures and their management.

Polymer-based gadolinium oxide nanocomposites for FL/MR/PA imaging guided and photothermal/photodynamic combined anti-tumor therapy.

Recently, ultrasmall gadolinium oxide (Gd2O3) nanoparticles with high longitudinal relaxation rate have received enormous attention. However, it can't be concentrated in tumor site through intravenous administration due to its ultrasmall size. In this project, we coated ultrasmall Gd2O3 nanoparticles with a near-infrared (NIR) light-absorbing polymer polypyrrole (PPy), modifying with hyaluronic acid (HA) and loaded aluminum phthalocyanine (AlPc), the Gd2O3@PPy/AlPc-HA nanoparticles could be used for fluorescence (FL)/magnetic resonance (MR)/photoacoustic (PA) imaging guided as well as remotely controlled PTT/PDT combined anti-tumor therapy. Polymerized PPy with high photothermal conversion efficiency was introduced to assemble the ultrasmall Gd2O3 nanoparticles which have high longitudinal relaxation rate and signal-to-noise ratio, thus obtaining Gd2O3@PPy nanoparticles which possess a larger particle size and can be more suitable for tumor targeting based on the EPR effect. HA and AlPc were adsorbed on PPy for HA-mediated tumor targeting and photodynamic therapy respectively. The in vivo triple-modal imaging revealed that Gd2O3@PPy/AlPc-HA nanoparticles possess enhanced tumor uptake effect after intravenous injection. More importantly, the nanoparticles exhibited an obvious photothermal effect, which can trigger the release and de-quench of AlPc. The anti-tumor efficiency further corroborated that the combined therapy achieved an excellent tumor inhibition therapeutic effect which was much better than any other mono-therapy. Consequently, our work encouraged further exploration of polymer-based multifunctional theranostic nanoparticles for cancer combination therapy under remote near-infrared (NIR) light controls.

Science to Practice: Enhancing Photothermal Ablation of Colorectal Liver Metastases with Targeted Hybrid Nanoparticles.

Image-guided percutaneous thermal ablation has been one of the principal tools in management of unresectable liver malignancies, including colorectal liver metastases (CRLM) ( 1 ). Currently, however, this technique is suitable mainly for tumors less than 4-5 cm in diameter and also results in incomplete ablation at tumor margins ( 2 ). To solve these problems, efforts have been made to combine thermal ablation with other treatment options, such as systemic and intra-arterial administration of therapeutics ( 3 - 5 ). In this issue of Radiology, White et al ( 6 ) introduced their work on development of an alternative approach by using biofunctionalized hybrid magnetic gold nanoparticles (HNPs) as catalysts for photothermal ablation of CRLM. They found that (a) the targeted (anti-MG1) HNPs are noncytotoxic and have greater than 20% intratumoral accumulation and (b) systemic administration of anti-MG1 HNPs can enlarge a tumor's necrotic zone with photothermal ablation. The results of this study establish the proof of the concept that targeted HNPs can enhance the therapeutic effect of photothermal ablation, which presents an exciting strategy for complete removal of CRLM by integrating two rapidly advancing scientific fields-interventional radiology and nanotechnology.

Circadian MicroRNAs in Cardioprotection.

The most dramatic feature of life on Earth is our adaptation to the cycle of day and night. Throughout evolutionary time, almost all living organisms developed a molecular clock linked to the light-dark cycles of the sun. In present time, we know that this molecular clock is crucial to maintain metabolic and physiological homeostasis. Indeed, a dysregulated molecular clockwork is a major contributing factor to many metabolic diseases. In fact, the time of onset of acute myocardial infarction exhibits a circadian periodicity and recent studies have found that the light regulated circadian rhythm protein Period 2 (PER2) elicits endogenous cardioprotection from ischemia. Manipulating the molecular clockwork may prove beneficial during myocardial ischemia in humans. MicroRNAs are small non-coding RNA molecules capable of silencing messenger RNA (mRNA) targets. MicroRNA dysregulation has been linked to cancer development, cardiovascular and neurological diseases, lipid metabolism, and impaired immunity. Therefore, microRNAs are gaining interest as putative novel disease biomarkers and therapeutic targets. To identify circadian microRNA-based cardioprotective pathways, a recent study evaluated transcriptional changes of PER2 dependent microRNAs during myocardial ischemia. Out of 352 most abundantly expressed microRNAs, miR-21 was amongst the top PER2 dependent microRNAs and was shown to mediate PER2 elicited cardioprotection. Further analysis suggested circadian entrainment via intense light therapy to be a potential strategy to enhance miR-21 activity in humans. In this review, we will focus on circadian microRNAs in the context of cardioprotection and will highlight new discoveries, which could lead to novel therapeutic concepts to treat myocardial ischemia.

A Systematic Review of Light Emitting Diode (LED) Phototherapy for Treatment of Psoriasis: An Emerging Therapeutic Modality.

Background: Psoriasis is a chronic, inflammatory skin condition. The economic burden of psoriasis is approximately $35.2 billion in the United States per year, and treatment costs are increasing at a higher rate than general inflation. Light emitting diode (LED) phototherapy may represent a cost-effective, efficacious, safe, and portable treatment modality for psoriasis.

Objective: The goal of our manuscript is to review the published literature and provide evidence-based recommendations on LED phototherapy for the treatment of psoriasis.

Methods & Materials: A search of the databases Pubmed, EMBASE, Web of Science, and CINAHL was performed on April 5, 2016. Key search terms were related to psoriasis and LED-based therapies.

Results: A total of 7,793 articles were generated from the initial search and 5 original articles met inclusion criteria for our review. Grade of recommendation: B for LED-blue light. Grade of recommendation: C for LED-ultraviolet B, LED-red light, and combination LED-near-infrared and LED-red light.

Conclusion: We envision further characterizing the effects of LED phototherapy to treat psoriasis in patients may increase adoption of LED-based modalities and provide clinicians and patients with new therapeutic options that balance safety, efficacy, and cost.

J Drugs Dermatol. 2017;16(5):482-488.

Recent Advances of Light-Mediated Theranostics.

Currently, precision theranostics have been extensively demanded for the effective treatment of various human diseases. Currently, efficient therapy at the targeted disease areas still remains challenging since most available drug molecules lack of selectivity to the pathological sites. Among different approaches, light-mediated therapeutic strategy has recently emerged as a promising and powerful tool to precisely control the activation of therapeutic reagents and imaging probes in vitro and in vivo, mostly attributed to its unique properties including minimally invasive capability and highly spatiotemporal resolution. Although it has achieved initial success, the conventional strategies for light-mediated theranostics are mostly based on the light with short wavelength (e.g., UV or visible light), which may usually suffer from several undesired drawbacks, such as limited tissue penetration depth, unavoidable light absorption/scattering and potential phototoxicity to healthy tissues, etc. Therefore, a near-infrared (NIR) light-mediated approach on the basis of long-wavelength light (700-1000 nm) irradiation, which displays deep-tissue penetration, minimized photo-damage and low autofluoresence in living systems, has been proposed as an inspiring alternative for precisely phototherapeutic applications in the last decades. Despite numerous NIR light-responsive molecules have been currently proposed for clinical applications, several inherent drawbacks, such as troublesome synthetic procedures, low water solubility and limited accumulation abilities in targeted areas, heavily restrict their applications in deep-tissue therapeutic and imaging studies. Thanks to the amazing properties of several nanomaterials with large extinction coefficient in the NIR region, the construction of NIR light responsive nanoplatforms with multifunctions have become promising approaches for deep-seated diseases diagnosis and therapy. In this review, we summarized various light-triggered theranostic strategies and introduced their great advances in biomedical applications in recent years. Moreover, some other promising light-assisted techniques, such as photoacoustic and Cerenkov radiation, were also systemically discussed. Finally, the potential challenges and future perspectives for light-mediated deep-tissue diagnosis and therapeutics were proposed.

Caracterización de pacientes pediátricos usuarios de fototerapia en el Servicio de Dermatología, Hospital Clínico Universidad de Chile (2007-2015) / Characterization of pediatrics patients users of phototherapy in dermatology service, Hospital Clínico Universidad Chile (2007-2015)

Phototherapy is the use of specific wavelenghts of light that have shown effectiveness in the treatment of several cutaneous diseases. Current indications for phototherapy in Dermatology include multiple pathologies and it is considered to be costeffective. Literature about its use in children is rare, there are no studies on phototherapy in Chilean children. Patients and methods: Observational, descriptive, retrospective study. Clinical records of pediatric patients treated with phototherapy at University of Chile Clinical Hospital between 2007 and 2015, were studied. For each patient, the following parameters were analyzed: age of starting treatment, sex, skin phenotype, diagnosis, prescribed phototherapy and weekly frecuency. Results: 146 patients, 85 girls and 51 boys, average age 11.7 +/- 4.0 years. Predominant skin phenotype, was Fitzpatrick type III. Vitiligo was identified as the most common indication for phototherapy (52,2 percent), followed by psoriasis (22,6 percent). By a large margin, the most used type of phototherapy was nb UVB (96.6 percent). Most of the patients were treated twice per week (69.2 percent). Discussion: The obtained results in this group are similar to those results described in the international literature. Further studies are required for a better knowledge about efficacy and possible long-term effects of phototherapy on Chilean children.

Review of the 94th Annual Meeting of the British Association of Dermatologists, Glasgow 2014.

This is a review of the 94th Annual Meeting of the British Association of Dermatologists, held in Glasgow from 1 to 3 July 2014. The conference covered some of the latest developments in the treatment of atopic dermatitis, psoriasis and cancer, a follow-up on the methylisothiazolinone contact allergy epidemic, advances in genetically inherited disorders and somatic mutations underlying birth marks. In addition, there was an international perspective on vitiligo, leprosy and HIV, and a session discussing the regulatory process behind pharmaceutical development.

Near-infrared Light Activatable Multimodal Gold Nanostructures Platform: An Emerging Paradigm for Cancer Therapy.

Traditional therapy for cancer is subject to some evident obstacles, including low effectiveness, resistance, systemic complication, etc. Gold nanostructures responsive to near-infrared (NIR) light are attractive for non-invasive and targeted therapy because of their unique physical properties especially strong absorption and scattering, and high surface area-to-volume ratio as well as the ease of which their surface chemistry can be manipulated to enhance biocompatibility surface modification and functionalization. In this Review, the progress of photothermal therapy (PTT) as well as the targeted delivery of anticancer agents as the predominant applications of gold nanostructures is detailed, with a focus on imaging-guided therapy and optimizing operational parameters. The NIR light-controlled targeted delivery and/or photothermal ablation of gold nanostructures in the treatment of metastasis are also briefly discussed. These gold nanostructures pave the way for developing better therapeutic strategies of cancer.

Phototherapy for mycosis fungoides.

BACKGROUND: Both phototherapy and photochemotherapy have been used in all stages of mycosis fungoides since they improve the symptoms and have a favourable adverse effect profile. MATERIALS AND METHODS: We performed an extensive search of published literature using keywords like "phototherapy", "photochemotherapy", "NBUVB", "PUVA", "UVA1", "mycosis fungoides", and "Sezary syndrome", and included systematic reviews, meta-analysis, national guidelines, randomized controlled trials (RCTs), prospective open label studies, and retrospective case series. These were then arranged according to their levels of evidence. RESULTS: Five hundred and forty three studies were evaluated, of which 107 fulfilled the criteria for inclusion in the guidelines. CONCLUSIONS AND RECOMMENDATIONS: Photochemotherapy in the form of psoralens with ultraviolet A (PUVA) is a safe, effective, and well tolerated first line therapy for the management of early stage mycosis fungoides (MF), that is, stage IA, IB, and IIA (Level of evidence 1+, Grade of recommendation B). The evidence for phototherapy in the form of narrow-band UVB (NB-UVB) is less robust (Level of evidence 2++, Grade of recommendation B) but may be considered at least as effective as PUVA in the treatment of early-stage MF as an initial therapy. In patients with patches and thin plaques, NB-UVB should be preferentially used. PUVA may be reserved for patients with thick plaques and those who relapse after initial NB-UVB therapy. For inducing remission, three treatment sessions per week of PUVA phototherapy or three sessions per week of NB-UVB phototherapy may be advised till the patient achieves complete remission. In cases of relapse, patients may be started again on PUVA monotherapy or PUVA may be combined with adjuvants like methotrexate and interferon (Level of evidence 2+, Grade of recommendation B). Patients with early-stage MF show good response to combination treatments like PUVA with methotrexate, bexarotene or interferon-α-2b. However, whether these combinations hold a significant advantage over monotherapy is inconclusive. For late stage MF, the above-mentioned combination therapy may be used as first-line treatment (Level of evidence 3, Grade of recommendation C). Currently, there is no consensus regarding maintenance therapy with phototherapy once remission is achieved. Maintenance therapy should not be employed for PUVA routinely and may be reserved for patients who experience an early relapse after an initial course of phototherapy (Level of evidence 2+, Grade of recommendation B). Bath-water PUVA may be tried as an alternative to oral PUVA in case the latter cannot be administered as the former may show similar efficacy (Level of evidence 2-, Grade of recommendation C). In pediatric MF and in hypopigmented MF, both NB-UVB and PUVA may be tried (Level of evidence 3, Grade of recommendation D).

Recent advances in primary cutaneous T-cell lymphoma.

PURPOSE OF REVIEW: Cutaneous T-cell lymphoma (CTCL) is a heterogeneous group of skin-homing T-cell neoplasms, which represent approximately 75% of all primary cutaneous lymphomas. Currently available drug therapies, when effective, simply control disease and the only option for curing CTCL is stem cell transplant. RECENT FINDINGS: In the last year, there has been an incredible effort made to improve the understanding and treatment of CTCL. Recent findings indicate that epigenetic aberrations are integral to active disease. Furthermore, multiple tumor-derived immunological factors have also been shown to inhibit viability, proliferation, and cytokine production of nonmalignant T cells. Several novel targeted therapies show great potential, most promising being antibody drug conjugates targeting surface markers such as CD30 in some CTCL subtypes. Additional attractive targets involve the global modulation of epigenetic markers such as demethylation agents or HDAC inhibitors, either as single agents or in combination therapies. SUMMARY: This is a concise review of recent advances in the field of CTCL with special focus on research articles over the preceding year.

[What's new in paediatric dermatology?]. / Quoi de neuf en dermatologie pédiatrique?

Regular analysis of the major journals in dermatology and paediatrics has been used to select forty articles which are representative of the past year in paediatric dermatology. This selection is not exhaustive but rather reflects the interests of the author and also the dominant topics in paediatric dermatology in 2013-2014.