Tamm Plasmon Resonance as Optical Fingerprint of Silver/Bacteria Interaction

The incorporation of responsive elements into photonic crystals is an effective strategy for fabricating active optical components to be used as sensors, actuators, and modulators. In particular, the combination of simple multilayered dielectric mirrors with optically responsive plasmonic materials has proven to be successful. Recently, Tamm plasmon (TP) modes have emerged as powerful tools for these purposes. These modes arise at the interface between a distributed Bragg reflector (DBR) and a plasmonic layer and can be excited at a normal incidence angle. Although the TP field is located usually at the DBR/metal interface, recent studies have demonstrated that nanoscale corrugation of the metal layer permits access to the TP mode from outside, thus opening exciting perspectives for many real-life applications. In this study, we show that the TP resonance obtained by capping a DBR with a nanostructured layer of silver is responsive to Escherichia coli. Our data indicate that the modification of the TP mode originates from the well-known capability of silver to interact with bacteria, within a process in which the release of Ag⁺ ions leaves an excess of negative charge in the metal lattice. Finally, we exploited this effect to devise a case study in which we optically differentiated between the presence of proliferative and nonproliferative bacteria using the TP resonance as a read-out. These findings make these devices promising all-optical probes for bacterial metabolic activity, including their response to external stressors.

Near-Infrared Plasmon-Induced Hot Electron Extraction Evidence in an Indium Tin Oxide Nanoparticle/Monolayer Molybdenum Disulfide Heterostructure

In this work, we observe plasmon-induced hot electron extraction in a heterojunction between indium tin oxide nanocrystals and monolayer molybdenum disulfide. We study the sample with ultrafast differential transmission, exciting the sample at 1750 nm where the intense localized plasmon surface resonance of the indium tin oxide nanocrystals is and where the monolayer molybdenum disulfide does not absorb light. With the excitation at 1750 nm, we observe the excitonic features of molybdenum disulfide in the visible range, close to the exciton of molybdenum disulfide. Such a phenomenon can be ascribed to a charge transfer between indium tin oxide nanocrystals and monolayer molybdenum disulfide upon plasmon excitation. These results are a first step toward the implementation of near-infrared plasmonic materials for photoconversion.

Effective medium optical modelling of indium tin oxide nanocrystal films

Doped semiconductor nanocrystal-based thin films are widely used for many applications, such as screens, electrochromic windows, light emitting diodes, and solar cells. Herein, we have employed spectroscopic ellipsometry to measure and model the complex dielectric response of indium tin oxide films fabricated by nanocrystal deposition and sintering. The films could be modelled as Bruggemann effective media, allowing estimation of the nanoscale interstitial porosity of the structure. The effective dielectric constants show the possibility of tuning the plasma frequency and the epsilon-near zero condition of the film.

Deciphering Photoinduced Charge Transfer Dynamics in a Cross-Linked Graphene-Dye Nanohybrid

The search for synthetic materials that mimic natural photosynthesis by converting solar energy into other more useful forms of energy is an ever-growing research endeavor. Graphene-based materials, with their exceptional electronic and optical properties, are exemplary candidates for high-efficiency solar energy harvesting devices. High photoactivity can be conveniently achieved by functionalizing graphene with small molecule organic semiconductors whose band-gaps can be tuned by structural modification, leading to interactions between the π-conjugated electronic systems in both the semiconductor and graphene. Here we investigate the ultrafast transient optical properties of a cross-linked graphene-dye (diphenyl-dithiophenediketopyrrolopyrrole) nanohybrid material, in which oligomers of the organic semiconductor dye are covalently bound to a random network of few-layer graphene flakes, and compare the results to those obtained for the reference dye monomer. Using a combination of ultrafast transient absorption and two-dimensional electronic spectroscopy, we provide substantial evidence for photoinduced charge transfer that occurs within 18 ps in the nanohybrid system. Notably, subpicosecond photoinduced torsional relaxation observed in the constituent dye monomer is absent in the cross-linked nanohybrid system. Through density functional theory calculations, we compare the competing effects of covalent bonding, increasing conjugation length, and the presence of multiple graphene flakes. We find evidence that the observed ultrafast charge transfer process occurs through a superexchange mechanism in which the oligomeric dye bridge provides virtual states enabling charge transfer between graphene-dye covalent bond sites.

Revealing excited states dynamics in cross-linked covalent hybrids of graphene and diketopyrrolopyrrole oligomers via ultrafast transient absorption spectroscopy

We report on ultrafast dynamics in cross-linked covalent hybrids of graphene and diketopyrrolopyrrole (TDPP) oligomers. Comparisons between non-polymerizing (EXG-TDPP) and polymerizing (c-EXG-TDPP) hybrids show that charge/energy transfer occurs faster than 50 ps in EXGTDPP, while the c-EXG-TDPP system shows quenching within 18 ps. The transient response of c-EXGTDPP is completely quenched (>99%), while in EXG-TDPP full quenching occurs after 1.39 ns. Photocurrent studies of c-EXG-TDPP films show IPCE > 2%, indicating ultrafast charge transfer between TDPP and graphene.

Investigational Drug Therapies for Overactive Bladder Syndrome: The Potential Alternatives to Anticolinergics

Background

Overactive bladder is a high prevalent and quality of life affecting disease. The mainstay of the medical therapy is represented by antimuscarinic drugs, but their side effects markedly affect patient compliance and prompt studies on novel investigational drugs.

Methods

A systematic literature search of peer-reviewed papers and meeting abstracts published by December 2008 was performed. PubMed databank was searched for original English articles, by using the following search terms: “overactive bladder” or “detrusor overactivity” or “urinary incontinence” and “treatment”, alone and linked to any potential molecular target or novel drug cited in the literature.

Results

Effective alternative pharmacological treatments are currently scarce, but many new promising compounds are emerging which target key molecular pathways involved in micturition control. The most promising potential therapeutic targets include central nervous system GABAergic inhibitory pathway, dopaminergic and serotoninergic systems, b-adrenoceptors and cAMP metabolism, nonadrenergic-noncholinergic mechanisms such as purinergic and neuropeptidergic systems, vanilloid receptor, bladder sensory nervous terminals, nonneuronal bladder signalling systems including urothelium and interstitial cells, prostanoids, Rho-kinase and different subtypes of potassium and calcium channels.

Conclusions

Despite the enormous amount of new biologic insight, very few novel pharmacological therapies seems to have passed the proof-of-concept clinical stage. The ultimate clinical utility of new drugs will depend on the ability to exploit tissue-specific differences and disease-related changes in molecular expression/function and to improve storage phase dysfunctions without interfering with the emptying phase. Further preclinical investigations and controlled clinical trials are urgently needed in this challenging field.

Sports and Genitourinary Traumas

Introduction

Statistical data referring to sports-related traumas of the urinary tract are quite scarce; nevertheless, it is possible to draw general data on the relationship between sports and urological traumas.

Methods

Literature review of peer-reviewed articles published by May 2009.

Results

Urological traumas account for about 10% of all traumas, and about 13% of them is sports-related. Genitourinary traumas are among the most common cause of abdominal injuries in sports. Blunt injuries are more common than penetrating ones and renal injuries are by far the most common, followed by testicular injuries; ureters, bladder and penis injuries are much more infrequent. Considering chronic microtraumas, injuries of bulbar urethra are also common in sports that involve riding. Overall, the incidence of genitourinary trauma due to sports is low. Renal traumas in sports injuries usually consist of grade 1–11 lesions and usually do not require surgical treatment. Cycling is the sporting activity most commonly associated with genitourinary injuries, followed by winter sports, horse riding and contact/collision sports. Literature data suggest that significant injuries are rare also in athletes with only one testicle or kidney. General preventive measures against sport-related injuries, along with the use of protective cups for male external genitalia, are generally sufficient to reduce the incidence of urogenital trauma.

Conclusions

Overall, studies show that urogenital injuries are uncommon in team and individual sports, and that most of them are low-grade injuries. Participation in sports that involve the potential for contact or collision needs to be carefully assessed in the athletes with only one testicle or kidney, even though urogenital injuries should not preclude sports participation to an appropriately informed and counseled patient. Further research is needed to acquire more knowledge on genitourinary injuries according to age, sports type and technical skill.

Prostatitis Syndromes and Sporting Activities

Introduction

Prostatitis-like syndromes are high prevalent health problems and frequently considered by patients and physicians as strictly correlated to sports causing perineal compression. These syndromes and their relationships with sporting activities have been discussed in this report.

Methods

We reviewed peer-reviewed scientific articles published by May 2009 and searched according to the following term selection: prostatitis, pudendal nerve, sport, cycling.

Results

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a major healthcare burden heavily affecting patients’ Quality of Life. No clear evidence of any direct etiologic relationship has been found in literature between prostatitis, either bacterial or non-bacterial, and sports activities. On the other hand, some types of sport causing perineal compression, such as cycling, can exacerbate symptoms of acute and chronic prostatitis; a temporary sport discontinuation is justified in these patients. CP/CPPS may be often caused by pudendal nerve entrapment (PNE). Prostatitis-like urogenital neuropathic pain together with voiding and sexual dysfunctions are the hallmark of PNE. A common feature is that flexion activities of the hip, such as climbing, squatting, cycling provoke or worsen urogenital pain or pelvic pain. Many of the patients with PNE are cyclists, played American football, lifted weights, or wrestled as teenagers and young adults. PNE represents the most common bicycling associated urogenital problems.

Conclusions

Overall, studies show that no causal relationship has been demonstrated between prostatitis and sporting activities. Conversely, urologists should be aware that sports involving vigorous hip flexion activities or prolonged perineal compression are a potential and not an infrequent cause of uroand rological symptoms caused by pudendal nerve entrapment.

Bladder Tumor Markers: A Review of the Literature

Bladder cancer is among the top eight most frequent cancers. Its natural history is related to a combination of factors that impact on its aggressiveness. Cystoscopy and urine cytology are the currently used techniques for the diagnosis and surveillance of non-invasive bladder tumors. The sensitivity of urine cytology for diagnosis is not high, particularly in low-grade tumors. The combination of voided urine cytology and new diagnostic urine tests would be ideal for the diagnosis and follow-up of bladder cancer. However, in order to have some clinical utility, new diagnostic and/or prognostic markers should achieve better predictive capacity that the currently used diagnostic tools. None of the markers evaluated over the last years showed remarkable sensitivity or specificity for the identification of any of the diverse types of bladder cancer in clinical practice. The limitations of the known prognostic markers have led to the research of new molecular markers for early detection of bladder cancer. This research focused in particular on the discovery of biomarkers capable of reducing the need for periodic cystoscopies or, ideally, offering a non-invasive examination instead. In this review, we will examine various new markers of bladder cancer and their value in the diagnosis and follow-up of non-muscle-invasive bladder cancer. When compared with urine cytology, which showed the highest specificity, most of these markers demonstrated an increased sensitivity.

Value of current chemotherapy and surgery in advanced and metastatic bladder cancer

The aim of the present paper was to review findings from the most relevant studies and to evaluate the value of current chemotherapy and surgery in advanced unresectable and metastatic bladder cancer. Studies were identified by searching the MEDLINE® and PubMed® databases up to 2011 using both medical subject heading (Mesh) and a free text strategy with the name of the known individual chemotherapeutic drug and the following key words: 'muscle-invasive bladder cancer', 'chemotherapeutics agents', and 'surgery in advanced bladder cancer'. At the end of our literature research we selected 141 articles complying with the aim of the review. The results showed that it has been many years since the MVAC (methotrexate, vinblastine, adriamycin, cisplatin) regimen was first developed. The use of cisplatin-based combination chemotherapy is associated with significant toxicity and produces long-term survival in only approximately 15-20% of patients. Gemcitabine + cisplatin represents the gold standard in the treatment of metastatic bladder cancer. In conclusion, the optimal approach in the management of advanced urothelial cancer continues to evolve. Further progress relies on the expansion of research into tumor biology and an understanding of the underlying molecular 'fingerprints' that can be used to enhance diagnostic and therapeutic strategies. Cisplatin-based therapy has had the best track record thus far.

[Prostatitis syndromes and sporting activities]

INTRODUCTION

Prostatitis-like syndromes are high prevalent health problems and frequently considered by patients and physicians as strictly correlated to sports causing perineal compression. These syndromes and their relationships with sporting activities have been discussed in this report.

METHODS

We reviewed peer-reviewed scientific articles published by May 2009 and searched according to the following term selection: prostatitis, pudendal nerve, sport, cycling.

RESULTS

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a major healthcare burden heavily affecting patients' Quality of Life. No clear evidence of any direct etiologic relationship has been found in literature between prostatitis, either bacterial or non-bacterial, and sports activities. On the other hand, some types of sport causing perineal compression, such as cycling, can exacerbate symptoms of acute and chronic prostatitis; a temporary sport discontinuation is justified in these patients. CP/CPPS may be often caused by pudendal nerve entrapment (PNE). Prostatitis-like urogenital neuropathic pain together with voiding and sexual dysfunctions are the hallmark of PNE. A common feature is that flexion activities of the hip, such as climbing, squatting, cycling provoke or worsen urogenital pain or pelvic pain. Many of the patients with PNE are cyclists, played American football, lifted weights, or wrestled as teenagers and young adults. PNE represents the most common bicycling associated urogenital problems.

CONCLUSIONS

Overall, studies show that no causal relationship has been demonstrated between prostatitis and sporting activities. Conversely, urologists should be aware that sports involving vigorous hip flexion activities or prolonged perineal compression are a potential and not an infrequent cause of uroandrological symptoms caused by pudendal nerve entrapment.

[Sports and genitourinary traumas]

INTRODUCTION

Statistical data referring to sports-related traumas of the urinary tract are quite scarce; nevertheless, it is possible to draw general data on the relationship between sports and urological traumas.

METHODS

Literature review of peer-reviewed articles published by May 2009.

RESULTS

Urological traumas account for about 10% of all traumas, and about 13% of them is sports-related. Genitourinary traumas are among the most common cause of abdominal injuries in sports. Blunt injuries are more common than penetrating ones and renal injuries are by far the most common, followed by testicular injuries; ureters, bladder and penis injuries are much more infrequent. Considering chronic microtraumas, injuries of bulbar urethra are also common in sports that involve riding. Overall, the incidence of genitourinary trauma due to sports is low. Renal traumas in sports injuries usually consist of grade I-II lesions and usually do not require surgical treatment. Cycling is the sporting activity most commonly associated with genitourinary injuries, followed by winter sports, horse riding and contact/collision sports. Literature data suggest that significant injuries are rare also in athletes with only one testicle or kidney. General preventive measures against sport-related injuries, along with the use of protective cups for male external genitalia, are generally sufficient to reduce the incidence of urogenital trauma.

CONCLUSIONS

Overall, studies show that urogenital injuries are uncommon in team and individual sports, and that most of them are low-grade injuries. Participation in sports that involve the potential for contact or collision needs to be carefully assessed in the athletes with only one testicle or kidney, even though urogenital injuries should not preclude sports participation to an appropriately informed and counseled patient. Further research is needed to acquire more knowledge on genitourinary injuries according to age, sports type and technical skill.