Multi-Lagrangians for Integrable Systems

We propose a general scheme to construct multiple Lagrangians for completely integrable non-linear evolution equations that admit multi- Hamiltonian structure. The recursion operator plays a fundamental role in this construction. We use a conserved quantity higher/lower than the Hamiltonian in the potential part of the new Lagrangian and determine the corresponding kinetic terms by generating the appropriate momentum map. This leads to some remarkable new developments. We show that nonlinear evolutionary systems that admit $N$-fold first order local Hamiltonian structure can be cast into variational form with $2N-1$ Lagrangians which will be local functionals of Clebsch potentials. This number increases to $3N-2$ when the Miura transformation is invertible. Furthermore we construct a new Lagrangian for polytropic gas dynamics in $1+1$ dimensions which is a {\it local} functional of the physical field variables, namely density and velocity, thus dispensing with the necessity of introducing Clebsch potentials entirely. This is a consequence of bi-Hamiltonian structure with a compatible pair of first and third order Hamiltonian operators derived from Sheftel's recursion operator.Comment: typos corrected and a reference adde

Quantization with maximally degenerate Poisson brackets: The harmonic oscillator!

Nambu's construction of multi-linear brackets for super-integrable systems can be thought of as degenerate Poisson brackets with a maximal set of Casimirs in their kernel. By introducing privileged coordinates in phase space these degenerate Poisson brackets are brought to the form of Heisenberg's equations. We propose a definition for constructing quantum operators for classical functions which enables us to turn the maximally degenerate Poisson brackets into operators. They pose a set of eigenvalue problems for a new state vector. The requirement of the single valuedness of this eigenfunction leads to quantization. The example of the harmonic oscillator is used to illustrate this general procedure for quantizing a class of maximally super-integrable systems

Borelli's lactritmel agar induces conidiation in rare-macroconidia producing dermatophytic fungi

PubMedID: 22563856Macroconidia are among the most important indicators used to identify dermatophytic fungi, but several do not usually sporulate and/or produce macroconidia on Sabouraud glucose agar. Specifically, Microsporum audouinii, M. ferrugineum, Trichophyton concentricum, T. schoenleinii, T. verrucosum, and T. violaceum (including T. soudanense and T. yaoundei) rarely form macroconidia and, therefore, cannot be easily identified. In this study, we investigated the production of macroconidia on nine common laboratory media, including Borelli's lactritmel agar (BLA), modified Borelli's lactritmel agar (MBLA), brain heart infusion agar (BHIA), Christensen's urease agar in Petri dishes (UPA), cornmeal dextrose agar (CMDA), Lowenstein-Jensen agar (LJA), malt extract agar (MEA), oatmeal agar (OA), and potato dextrose agar (PDA). The performance of these media was evaluated using 18 rare-macroconidia producing isolates, including representative of the six species mentioned above. All cultures in this study were incubated at 26°C on the bench, and conidia formation on each was investigated at 5, 10, 15, 20, 25, and 30 days of incubation. BLA apparently improved macroconidia production after 15 days and was the most useful nutrient agar medium to induce these phenotypic characters in daily practice, closely followed by OA, PDA, and MBLA. © 2012 ISHAM

Comparison of the contamination rates of culture media used for isolation and identification of dermatophytes

PubMedID: 26281324Background/aim: Mycological media that promote spore production are essential for the diagnosis of dermatophytosis. However, these culture media frequently become contaminated by multiple fungal or bacterial species during culture. The aim of this study was to compare the contamination rates of 6 culture media used for the isolation and identification of dermatophytes, including Borelli’s lactritmel agar (BLA), brain-heart infusion agar (BHIA), Lowenstein–Jensen agar (LJA), malt extract agar (MEA), potato dextrose agar (PDA), and Sabouraud glucose agar (SGA). Materials and methods: Agar plates were inoculated with 43 well-characterized dermatophyte strains, belonging to the genera Arthroderma, Epidermophyton, Microsporum, or Trichophyton. The agar plates were incubated at 26 °C and examined every 5 days for 1 month. Results: By the end of the incubation period, 97 of the 258 plates (37.6%) were contaminated by fungi. No bacteria were detected. Overall, BLA demonstrated the lowest rate of contamination, followed by SGA, MEA, BHIA, PDA, and LJA. Sequencing of the internal transcribed spacer region rDNA of the contaminant fungi revealed that Aspergillus and Penicillium species were the most common contaminants. Conclusion: Tese results suggest that nonenriched culture media types, such as BLA or SGA, reduced contamination during dermatophyte subculture. © TÜBİTAK

Trichophyton tonsurans scalp carriage among wrestlers in a national competition in Turkey

Trichophyton tonsurans tinea gladiatorum is an emerging epidemic among combat-sport athletes across the globe. In the present study, we investigated the prevalence of symptomatic and asymptomatic dermatophytic infections among wrestlers in the National Greco-Roman Championship in Turkey. In total, 194 wrestlers from 32 provinces and 72 clubs were examined for scalp, trunk, groin, and toe web dermatophytic infections. We also administered a questionnaire to obtain information on the participants' lifestyles, wrestling characteristics, and risk factors for dermatophytic infections. The hairbrush method was used for scalp and trunk sampling, whereas a cotton swab was used for groin, toe web, and mat sampling. Three wrestling mats in the gymnasium were surveyed for dermatophytes using the touch preparation method. A total of 17 (8.8%) wrestlers harbored dermatophytes, and 22 strains were isolated: 13 (59.1%) T. tonsurans and 9 (40.9%) T. rubrum. These isolates were found on the scalp (8), trunk (2), forearm (1), hand (1), groin (3), and feet (7). In addition, we recovered 8 dermatophyte strains from the 150 mat samples (5.3%): T. rubrum in 6 samples (75%) and T. tonsurans in two samples (25%). T. tonsurans was only recovered from 11 out of 194 (5.7%) wrestlers. Scalp carriage represents the predominant (72.7%) clinical picture of a T. tonsurans infection in these Greco-Roman wrestlers in Turkey. © 2011 Springer Science+Business Media B.V.Acknowledgments The present study was partly supported by the Turkish Wrestling Federation. We gratefully acknowledge Mr. Önder Yaks¸i, the General Coordinator of the Turkish Wrestling Federation, who kindly helped in the organization of this study, making the present study possible. In addition, we appreciate and give our sincere thanks to two anonymous reviewers for their critical comments on earlier drafts of this paper

Haemolytic and co-haemolytic (CAMP-like) activity in dermatophytes

PubMedID: 25476038Dermatophytes are some of the most common fungal pathogens in both humans and animals. These fungi release enzymes (e.g., keratinases) that play roles in their pathogenesis. Little is known about their haemolytic and co-haemolytic (CAMP-like) activities; however, in bacteria, these components play significant roles in pathogenesis. This study characterised these two factors in 45 dermatophyte strains (representing the genera Arthroderma, Epidermophyton, Microsporum and Trichophyton) using Columbia agar (CA) supplemented with 5% bovine, ovine and equine erythrocytes. Haemolysis was best observed on CA supplemented with ovine erythrocytes followed by equine and bovine erythrocytes, while CAMP-like reactions occurred using bovine and ovine but not equine erythrocytes. Haemolytic and CAMP-like activities were best observed using ovine and bovine erythrocytes in CA in 44 and 38 strains at 7 and 3 days respectively. Most dermatophytes recovered from both symptomatic and asymptomatic lesions had haemolytic and CAMP-like activities. We suggest that the haemolytic and CAMP-like activities are not correlated with ecological characteristics, isolation sites or clinical manifestations of dermatophytic fungi. We also believe that this study has the potential to contribute to the existing literature on dermatophytes and dermatophyte pathogenesis. © 2014 Blackwell Verlag GmbH

The Use of Albino Adult Hair and Blond Prepubertal Hair Yields Equivalent Results in an In Vitro Hair Perforation Test to Differentiate Between Different Dermatophytic Fungi

PubMedID: 23591622An in vitro hair perforation test is used to differentiate isolates of Trichophyton mentagrophytes and Trichophyton rubrum complexes because morphological criteria are insufficient. Here, we performed in vitro hair perforation tests using blond prepubertal hair and albino adult hair to determine whether they differentiate between fungal species. We tested 43 well-characterized dermatophyte strains, Arthroderma spp. [n = 4], Epidermophyton floccosum [n = 1], Microsporum spp. [n = 8], and Trichophyton spp. [n = 30], and examined hair perforation at 3-30 days postinoculation (p.i.). The perforation times were not significantly different between the two hair types (P > 0.05). The T. mentagrophytes complex strains perforated hair 4-5 days p.i., whereas T. rubrum complex strains perforated hair 13-30 days p.i., except for Trichophyton violaceum, which perforated hair after 6-7 days. Thus, the hair perforation test is highly sensitive (100 %) and specific (100 %) for differentiating T. mentagrophytes from T. rubrum complexes 5 days p.i. At 14 and 30 days, the sensitivity and negative predictive value of the test remained unchanged (100 %), but the specificity was reduced (64.3 and 14.3 %, respectively). Consistent with previous reports, we observed "perforating organs" of zoophilic Microsporum canis and geophilic Microsporum gypseum at 4 and 3 days, respectively. This paper offers a "low-cost" and "low-tech" alternative to differentiating dermatophyte species where standard morphological techniques fail and/or where molecular techniques are not a viable option. © 2013 Springer Science+Business Media Dordrecht

Epidemiology of dermatophytosis in junior combat and non-combat sports participants

PubMedID: 22621172Participation in competitive sports is popular and widely encouraged worldwide. Herein, we investigated 252 male and 67 female sports players, aged 16.4±1.3years, active in 15 different types of combat (n=143) and non-combat (n=176) sports. Of the 319 participants in this study, 11 (3.5%) players, including six wrestlers, four football players and one handball player, all of whom were men, harboured dermatophytic fungi. Briefly, Trichophyton tonsurans was present in three athletes, who were scalp carriers of the fungus. Furthermore, T. rubrum (4), T. interdigitale (3) and Arthroderma simii (1) were recovered from eight participants with tinea inguinalis (4), tinea pedis (2) or both (1). One patient was a trunk carrier of concomitant tinea pedis. All dermatophytic fungi were identified using both direction sequence of the rDNA regions spanning the internal transcribed spacers (ITS1 and ITS2) and 5.8 rRNA gene. Although sports-active individuals are active and sweat more, we observed a low prevalence of dermatophytosis, both in combat (5.2%) and non-combat sports participants (3.4%) (P>0.05). However, dermatophyte infections require more attention and appropriate management to eradicate the infection and to prevent possible outbreaks. This study also documents the first case of zoophilic A. simii in Turkey. © 2012 Blackwell Verlag GmbH

Virulence markers of opportunistic black yeast in Exophiala

PubMedID: 26857806The black yeast genus Exophiala is known to cause a wide variety of diseases in severely ill individuals but can also affect immunocompetent individuals. Virulence markers and other physiological parameters were tested in eight clinical and 218 environmental strains, with a specific focus on human-dominated habitats for the latter. Urease and catalase were consistently present in all samples; four strains expressed proteinase and three strains expressed DNase, whereas none of the strains showed phospholipase, haemolysis, or co-haemolysis activities. Biofilm formation was identified in 30 (13.8%) of the environmental isolates, particularly in strains from dishwashers, and was noted in only two (25%) of the clinical strains. These results indicate that virulence factors are inconsistently present in the investigated Exophiala species, suggesting opportunism rather than pathogenicity. © 2016 Blackwell Verlag GmbH

Asymptomatic groin dermatophyte carriage detected during routine gynaecologic examinations

PubMedID: 23006021We investigated the epidemiological characteristics of both symptomatic and asymptomatic dermatophytic groin infections in 1970 women (age: 36.2±12.5) during routine gynaecologic examinations. Bilateral groin samples were collected with sterile cotton swabs premoistened with sterile physiological saline. The samples were then separately inoculated onto Sabouraud glucose agar. Fungi were identified by sequencing the rDNA internal transcribed spacer region. Dermatophytes were recovered from five patients (four Trichophyton rubrum and one Arthroderma vanbreuseghemii, 0.25%) with a diagnosis of asymptomatic carriers (four) and tinea inguinalis (one). In one case, groin carriage converted into tinea inguinalis after 3weeks. Analysis of risk factors indicated that patients of at least 49years were more likely to be positive for dermatophyte isolation (P=0.002). In conclusion, groin dermatophyte carriage is more common than tinea inguinalis and can potentially convert into a symptomatic infection. © 2012 Blackwell Verlag GmbH