Photodynamic Inactivation Of Microbial Pathogens

Photodynamic therapy (PDT) was discovered over one hundred years ago after observing the death of microorganisms upon exposure to dyes and light. It is the combination of non-toxic dyes and harmless visible light that, in the presence of oxygen, produce highly toxic reactive species. The principal medical application during the last century was in cancer therapy but, in these days of rising antibiotic resistance, PDT shows increasing promise as an alternative approach to treating infections. PDT has also been used in blood product sterilization, peridontology, acne reduction, and the treatment of viral lesions such as those caused by human papilloma virus. It may also have potential as an environmentally friendly pesticide. This is the first and only book to comprehensively cover the use of light and photosensitising agents for controlling microbial pathogens. It provides a comprehensive and up-to-date coverage of an emerging field. There are several chapters on the design of antimicrobial photosensitizers, their use to kill pathogenic organisms and their success in treating infections in animal models. It has long been known that gram-positive bacteria are highly susceptible to photoinactivation but the book also discusses means of widening the range of microorganisms that can be tackled by PDT. Edited by two pioneers in the application of PDT to medical and environmental issues, this book covers the basic science, translational research in animals, and the clinical applications in various medical specialities. It represents an indispensable resource for microbiologists and infectious disease doctors as well as dentists, dermatologists, gastroenterologists and transfusion specialists.

Increasing resistance of bacteria to antibiotics is a serious worldwide problem, and to combat resistant bacteria, new antibacterial approaches are to be developed. One alternative to traditional antibiotic therapy is photodynamic antimicrobial chemotherapy (PACT). PACT is based on excitation of photosensitizers (PS) capable of transferring the absorbed light energy to dissolved molecular oxygen causing generation of reactive oxygen species, which irreversibly damage bacterial cell components. The overall efficiency of PACT has been proven for Gram-positive and Gram-negative bacteria. The effectiveness of PACT can be increased by encapsulation of PS in liposomes providing more concentrated delivery of PS, enhanced cytotoxicity, improved pharmacokinetic properties, sustained release, and prolonged action of the PS. For continuous and reusable application, PS can be immobilized in polymers. Chemiluminescence, sonodynamic treatment, and radiofrequency irradiation allow to perform excitation of PS in the dark without external illumination, opening prospects for combating internal infections. Combination of PS with antibiotics can gain a synergistic effect, allowing in some cases to overcome the resistance of bacteria to antibiotics.

Antimicrobial susceptibility profile and effect of stem bark extracts of Curtisia dentata on multi-drug resistant verotoxic Escherichia coli and Acinetobacter spp. isolates obtained from water and wastewater samples / Hamuel James Doughari [und weitere]. Antimicrobial utilization in intensive care units of a private tertiary care hospital / Pramil Tiwari, Vani Yadav and Shilpi Singh. Bacterial clearance from blood in mice infected by S. pneumoniae (penicillin MIC = 16 ug/ml) presenting specific IgG (non-protective levels) and treated with sub-therapeutic regimens of cefditoren (a highly bound cephalosporin) / Fabio Cafini [und weitere]. Characterisation of methicillin resistant Staphylococcus aureus isolates from hospitalised patients / Vladimir Kmet, Daniela Ohlasova and Milan Niks. Characterization of methicillin-resistant coagulase-negative Staphylococci isolates from blood cultures in a Brazilian University Hospital / Valeria Cataneli Pereira and Maria de Lourdes Ribeiro de Souza da Cunha. Control of bacterial contamination in boar semen doses / J.M. Morrell and Margareta Wallgren. Diffusion of extended-spectrum B-lactamase producing Enterobacter cloacae in a kidney transplantation unit / S. Hammami [und weitere]. Effect of antifungal agents on non-Candida albicans Candida species enzymatic activity / M. Negri [und weitere]. Effect of chitosan, nisin and storage time on the growth of Listeria innocua and Shewanella putrefaciens in fish homogenates / L.I. Schelegueda, M.F. Gliemmo and C.A. Campos. ESBL-producing Enterobacteriaceae in the northern Portugal - antimicrobial susceptibility and molecular epidemiology / R. Fernandes and C. Prudencio. Observations on the antimicrobial susceptibility of Staphylococcus pseudintermedius following the introduction of cefovecin for clinical use in Europe / Y. Chaudhry, A. Robinson and K.S. Godinho. Oxacillin resistance among Staphylococcus aureus isolated from peritoneal dialysis related peritonitis / C.H. Camargo [und weitere]. Resistance detection and susceptibility profile in Staphylococcus spp. isolated from patients with urinary tract infection (UTI) / Adriano Martison Ferreira [und weitere]. Resistance distribution profile of MBL, ESBL and multidrug resistant Gram negatives isolated at a tertiary care hospital in India / K.H. Bhutada and V.R. Shende

Nanostructures for Antimicrobial Therapy discusses the pros and cons of the use of nanostructured materials in the prevention and eradication of infections, highlighting the efficient microbicidal effect of nanoparticles against antibiotic-resistant pathogens and biofilms. Conventional antibiotics are becoming ineffective towards microorganisms due to their widespread and often inappropriate use. As a result, the development of antibiotic resistance in microorganisms is increasingly being reported. New approaches are needed to confront the rising issues related to infectious diseases. The merging of biomaterials, such as chitosan, carrageenan, gelatin, poly (lactic-co-glycolic acid) with nanotechnology provides a promising platform for antimicrobial therapy as it provides a controlled way to target cells and induce the desired response without the adverse effects common to many traditional treatments. Nanoparticles represent one of the most promising therapeutic treatments to the problem caused by infectious micro-organisms resistant to traditional therapies. This volume discusses this promise in detail, and also discusses what challenges the greater use of nanoparticles might pose to medical professionals. The unique physiochemical properties of nanoparticles, combined with their growth inhibitory capacity against microbes has led to the upsurge in the research on nanoparticles as antimicrobials. The importance of bactericidal nanobiomaterials study will likely increase as development of resistant strains of bacteria against most potent antibiotics continues. Shows how nanoantibiotics can be used to more effectively treat disease Discusses the advantages and issues of a variety of different nanoantibiotics, enabling medics to select which best meets their needs Provides a cogent summary of recent developments in this field, allowing readers to quickly familiarize themselves with this topic area

This essential volume comprehensively discusses redox-active therapeutics, focusing particularly on their molecular design, mechanistic, pharmacological and medicinal aspects. The first section of the book describes the basic aspects of the chemistry and biology of redox-active drugs and includes a brief overview of the redox-based pathways involved in cancer and the medical aspects of redox-active drugs, assuming little in the way of prior knowledge. Subsequent sections and chapters describe more specialized aspects of central nervous system injuries, neurodegenerative diseases, pain, radiation injury and radioprotection (such as of brain, lungs, head and neck and erectile function) and neglected diseases (e.g., leishmaniasis). It encompasses several major classes of redox-active experimental therapeutics, which include porphyrins, salens, nitrones, and most notably metal-containing (e.g., Mn, Fe, Cu, Zn, Sb) drugs as either single compounds or formulations with nanomaterials and quantum dots. Numerous illustrations, tables and figures enhance and complement the text; extensive references to relevant literature are also included. Redox-Active Therapeutics is an invaluable addition to Springer’s Oxidative Stress in Applied Basic Research and Clinical Practice series. It is essential reading for researchers, clinicians and graduate students interested in understanding and exploring the Redoxome—the organism redox network—as an emerging frontier in drug design, redox biology and medicine.

This volume emphasizes the science underlying the various phototherapy procedures, which encompasses aspects of classical and molecular photophysics, biological photochemistry, photobiology and biophotonics. Suitable as an introductory reference or textbook.