Polymorphic Light Eruption: What's New in Pathogenesis and Management

Polymorphic light eruption is the commonest photosensitive disorder, characterized by an intermittent eruption of non-scarring erythematous papules, vesicles or plaques that develop within hours of ultraviolet radiation exposure of patient skin. Together with the lesions, a terrible itch starts and increases with the spreading of the disease, sometimes aggravated by a sort of burning sensation. Clinical picture and symptoms can improve during the rest of the summer with further solar exposures. In the last years many advances have been performed in the knowledge of its pathogenesis and some news have been proposed as preventive, as well as therapeutic options. All this has been discussed in the current mini review

Fohotodermatoses and Skin Cancer

Preface Skin cancer is one of the most common types of tumors in Western countries. In the United States only, more than one million people are diagnosed with skin cancer each year. Although the absolute number of skin cancer patients is increasing, the death is inversely decreasing, due to the early detection and treatment. Basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma are three major types of skin cancer. BCC and SCC rarely have metastasis; over 95 percent BCC and SCC patients can be cured. Melanoma only accounts for a small percentage of skin cancer, but it causes 75 percent death of this disease. In this book, we invited a number of experts to present their latest accomplishments on skin cancer research. Although the topics are varied, the authors did great work to help readers better understand skin cancer and learn the knowledge to prevent this disease. There are three sections in this book, starting with etiology. Ultraviolet (UV) light exposure is overwhelmingly believed to be the most frequent cause of skin cancer. In this section, the association between UV and photodermatoses, as well as skin cancer is discussed. Desmosomal cadherins are important molecules in tumor cell adhesion and invasion, and their important roles in BCC are also presented in details. In the diagnosis and treatment section, a few new methodologies are described. As known, the outcome of malignant melanoma greatly depends on the thickness of the tumor at the time of treatment. Accurate determination of melanoma lateral and depth of margins using non-invasive imaging technologies is of importance when making sound decisions for treatment and evaluating a five year survival rate. A novel method named differential scanning calorimetry is capable of predicting metastasis of melanoma patients by monitoring the temperature changes of plasma. Electronic miniature X-ray brachytherapy is introduced as a new technology to treat nonmelanoms skin cancer. Although its potential has not yet been fully realized, chemoprevention, in terms of using chemical agents that naturally occur in foods, or are administered as pharmaceuticals to retard or reverse the process of carcinogenesis and progression of cancer, has been recognized to benefit individuals with precancerous lesions or genetic susceptibilities to cancer. In the prevention section, two chapters summarized the most recognized dietary phytochemicals and their potential application in skin cancer. X Preface This book would not have been possible without the contributions of all authors and the support from the publisher. Especially, I will convey my sincere appreciation to Ms. Tajana Jevtic, who has always been available and supportive of me to accomplish this project. Yaguang Xi, M.D., Ph.D. Assistant Professor of Oncologic Sciences, University of South Alabama, US

Novel Approach for Evaluation of Bacteroides fragilis Protective Role against Bartonella henselae Liver Damage in Immunocompromised Murine Model

Bartonella henselae is a gram-negative facultative intracellular bacterium and is the causative agent of cat-scratch disease. Our previous data have established that Bacteroides fragilis colonization is able to prevent B. henselae damages through the polysaccharide A (PSA) in an experimental murine model. In order to determine whether the PSA is essential for the protection against pathogenic effects of B. henselae in immunocompromised hosts, SCID mice were co-infected with B. fragilis wild type or its mutant B. fragilis 1PSA and the effects of infection on murine tissues have been observed by High-Frequency Ultrasound (HFUS), histopathological examination, and Transmission Electron Microscopy (TEM). For the first time, echostructure, hepatic lobes length, vascular alterations, and indirect signs of hepatic dysfunctions, routinely used as signs of disease in humans, have been analyzed in an immunocompromised murine model. Our findings showed echostructural alterations in all infected mice compared with the Phosphate Buffer Solution (PBS) control group; further, those infected with B. henselae and co-infected with B. henselae/B. fragilis 1PSA presented the major echostructural alterations. Half of the mice infected with B. henselae and all those co-infected with B. henselae/B. fragilis 1PSA have showed an altered hepatic echogenicity compared with the renal cortex. The echogenicity score of co-infected mice with B. henselae/B. fragilis 1PSA differed significantly compared with the PBS control group (p < 0.05). Moreover the inflammation score of the histopathological evaluation was fairly concordant with ultrasound findings. Ultrastructural analysis performed by TEM revealed no significant alterations in liver samples of SCID mice infected with B. fragilis wild type while those infected with B. fragilis 1PSA showed the presence of collagen around the main vessels compared with the PBS control group. The liver samples of mice infected with B. henselae showed macro-areas rich in collagen, stellate cells, and histiocytic cells. Interestingly, our data demonstrated that immunocompromised SCID mice infected with B. henselaeand co-infected with B. henselae/B. fragilis ΔPSA showed the most severe morpho-structural liver damage. In addition, these results suggests that the HFUS together with histopathological evaluation could be considered good imaging approach to evaluate hepatic alterations

Immuno-Pathogenesis of Chronic Inflammatory Skin Diseases: Novel Molecular Targets and Biomarkers

Chronic inflammation has a crucial pathogenetic role in many diseases, including cutaneous chronic inflammatory disorders, such as psoriasis, atopic dermatitis, hidradenitis suppurativa, and chronic urticaria [...]

Guselkumab for the treatment of psoriasis

Psoriasis is a chronic immune mediated disease in which the interplay of T cells and keratinocytes seems to play a key role. In this context, the interleukin (IL)-23/IL-17 axis is currently considered to be crucial in the pathogenesis of psoriasis and the selective inhibition of IL-23 may be viewed as an improvement of treatments blocking both IL-23 and IL-12, since its upstream actions. Areas covered: The authors performed a thorough and updated review on guselkumab, a fully human IgG1λ monoclonal antibody that blocks the p19 subunit of IL-23, analyzing efficacy and safety data from phase I, II and III trials. Expert opinion: Guselkumab represents a very promising therapy, providing an alternative mechanism of action with high efficacy and safety profiles, sustained total skin clearance, and rapid onset of effect also to psoriasis patients who previously failed or experienced an inadequate response to anti-TNF-α or anti-IL12/23. Guselkumab will definitively shift therapeutic goals of psoriasis management from PASI 75 to PASI 90 and 100 due to its exciting trials results, also favored by its increased treatment adherence due to its administering regimen (100 mg injection at week 0, 4 and then every 8 weeks)

Guselkumab for the treatment of psoriasis

Psoriasis is a chronic immune mediated disease in which the interplay of T cells and keratinocytes seems to play a key role. In this context, the interleukin (IL)-23/IL-17 axis is currently considered to be crucial in the pathogenesis of psoriasis and the selective inhibition of IL-23 may be viewed as an improvement of treatments blocking both IL-23 and IL-12, since its upstream actions. Areas covered: The authors performed a thorough and updated review on guselkumab, a fully human IgG1λ monoclonal antibody that blocks the p19 subunit of IL-23, analyzing efficacy and safety data from phase I, II and III trials. Expert opinion: Guselkumab represents a very promising therapy, providing an alternative mechanism of action with high efficacy and safety profiles, sustained total skin clearance, and rapid onset of effect also to psoriasis patients who previously failed or experienced an inadequate response to anti-TNF-α or anti-IL12/23. Guselkumab will definitively shift therapeutic goals of psoriasis management from PASI 75 to PASI 90 and 100 due to its exciting trials results, also favored by its increased treatment adherence due to its administering regimen (100 mg injection at week 0, 4 and then every 8 weeks)