Fisheries & Stream Quality Update for the Kankakee River Basin

Author keywords: stream quality, index of biotic integrity, walleye stocking Scholarship domain: community applicatio

Fisheries & Stream Quality Update for the Kankakee River Basin

Author keywords: stream quality, index of biotic integrity, walleye stocking Scholarship domain: community applicatio

The Role of Heme Chirality in the Circular Dichroism of Heme Proteins

The rotational strength (R) of the Soret transition in sperm-whale myoglobin (SW Mb), the hemoglobin from Chirononms thummi thummi (C17 Hb), and human hemoglobin (hHb) has been calculated using 20 high-resolution ( R-aro > R-pep. For CTT Hb and hHB, the orders were, respectively, R-int > R-pep > R-aro and R-int > R-aro approximate to R-pep. Human Hb alpha chains showed the same trend as CTT Hb. Only in the hHb beta chains did R-aro predominate, with the order R-aro > R-iot > R-pep. The total predicted R-tot for SW Mb, CTT Hb, and hHb averaged +0.77 +/- 0.10 (0.56-0.80), -0.37 +/- 0.12 (-0.5), and +0.31 +/- 0.17 DBM (0.23-0.50), respectively. (Values in parentheses are experimental values.) Thus, contrary to the currently accepted view, coupling with aromatic side-chain or peptide transitions is not the dominant factor in the Soret circular dichroism (CD) of these proteins. The Soret CD is dominated by intrinsic CD of the heme chromophore, of which vinyl torsion is the major determinant. This result suggests an explanation for the large effect of heme isomerism on the Soret CD of Mb and Hb. Rotation about the alpha-gamma axis may be associated with large changes in vinyl torsion and thus substantially alter the intrinsic CD, even reversing its sign

Chiroptical Properties in Thin Films of π-Conjugated Systems

Chiral π-conjugated molecules provide new materials with outstanding features for current and perspective applications, especially in the field of optoelectronic devices. In thin films, processes such as charge conduction, light absorption, and emission are governed not only by the structure of the individual molecules but also by their supramolecular structures and intermolecular interactions to a large extent. Electronic circular dichroism, ECD, and its emission counterpart, circularly polarized luminescence, CPL, provide tools for studying aggregated states and the key properties to be sought for designing innovative devices. In this review, we shall present a comprehensive coverage of chiroptical properties measured on thin films of organic π-conjugated molecules. In the first part, we shall discuss some general concepts of ECD, CPL, and other chiroptical spectroscopies, with a focus on their applications to thin film samples. In the following, we will overview the existing literature on chiral π-conjugated systems whose thin films have been characterized by ECD and/or CPL, as well other chiroptical spectroscopies. Special emphasis will be put on systems with large dissymmetry factors (gabs and glum) and on the application of ECD and CPL to derive structural information on aggregated states

Impact and amplification of chirality in the aggregation of leucine-appended poly(p-phenylene ethynylene) (PPE)

A leucine-appended poly(p-phenyleneethynylene) (PPE) was prepared in enantiomeric stereoregular (L-1 and D-1) and stereorandom (rac-1) forms. The solution aggregates of L-1, D-1, rac-1, and mixtures of L-1/D-1, were characterized by absorption, electronic circular dichroism and emission spectra. Both rac-1 and L-1/D-1 mixtures are more prone to aggregate than L-1 and D-1. Upon aggregating, the enantiomeric mixtures manifest an apparent majority-rules effect, which is mostly due to the greater tendency to form heterochiral aggregates with respect to homochiral ones. The impact of chirality on the aggregation behaviour of the aminoacid-appended PPE is demonstrated

Circularly polarized light at the mirror: Caveats and opportunities

Moving from the simple concept that reflection onto a mirror surface changes the handedness of circularly polarized light, we describe what happens to the emergent polarization in two different cases after reflection on a back mirror. In the first case, a regular emitter is taken into account, where reflection has the effect to destroy the emergent polarization. In the second case, we show what could happen when a hypothetical apparently non-reciprocal emitting material undergoes a similar experiment. These simple concepts have important implications in the design of efficient circularly polarized emitting devices

Inherently chiral calix[4]arenes with planar chirality: two new entries to the family

The synthesis of two new inherently chiral calix[4]arenes (ICCs, 1 and 2), endowed with electron-rich concave surfaces, has been achieved through the desymmetrization of a lower rim distal-bridged oxacyclophane (OCP) macrocycle. The new highly emissive ICCs were resolved by chiral HPLC, and the enantiomeric nature of the isolated antipodes proved by electronic circular dichroism (CD). Using time-dependent density functional calculations of CD spectra, their absolute configurations were established. NMR studies with (S)-Pirkle's alcohol unequivocally showed that the host-guest interactions occur in the chiral pocket comprehending the calix-OCP exo cavities and the carbazole moieties

Plaque psoriasis in children and adolescents – the role of etanercept

Federica Ricceri, Lara Tripo, Leonardo Pescitelli, Francesca PrignanoDivision of Clinical, Preventive and Oncology Dermatology, Department of Critical Care Medicine and Surgery, University of Florence, Florence, ItalyBackground: Childhood-onset psoriasis affects approximately one-third of the psoriatic population. Among many potential treatments of childhood psoriasis, biological agents are emerging as a valuable option in the management of this disease. In Europe, etanercept has recently been approved for children aged 6 years and over. Data from a well-designed clinical trial indicate that in children, etanercept effectively reduces psoriasis symptoms, with beneficial effects evident as early as 4 weeks after the onset of therapy. The treatment is generally well tolerated; mild injection site reactions are the most common adverse events reported in the literature. Published data of etanercept use in children show promising results, but further clinical studies are necessary to confirm its long-term efficacy and safety.Keywords: pediatric psoriasis, anti-TNF-α, etanercep

Itch in psoriasis: epidemiology, clinical aspects and treatment options

F Prignano, F Ricceri, L Pescitelli, T LottiDepartment of Dermatological Sciences, University of Florence,Florence, ItalyBackground: Pruritus is an important symptom in psoriasis vulgaris, may be severe and seriously affect the quality of life of patients, but published data on its frequency and characteristics are limited.Objective: The study objective was to characterize the prevalence of itch in psoriatic patients and the effect of treatment modalities by using a comprehensive itch questionnaire of our own design.Methods: A structured itch questionnaire was given to 90 patients with moderate to severe chronic-plaque psoriasis selected consecutively from the patients visiting the Department of Dermatology of the University of Florence. The questionnaire concerned the areas involved in psoriasis and pruritus, the pruritus characteristics, the worsening and relieving factors and treatment modalities. Itch intensity was reflected by a 10 point visual analog scale (VAS) and the degree of symptoms discriminated between mild (1–3), moderate (4–7) and severe (8–10).Results: Almost 85% of psoriatic patients suffered from itching; the frequency of pruritus was daily and mean intensity by VAS scale was moderate. Presence and intensity of pruritus and body mass index (BMI) were correlated. 40% of patients with pruritus were overweight (BMI > 25 < 30) and 10% obese (BMI > 30). Almost all patients appeared unsatisfied with the available treatment modalities for pruritus in psoriasis. Emollients, topical steroids and calcipotriol cream could relieve pruritus but their effect was temporary. Among the antipsoriatic therapies, phototherapy with narrow band ultraviolet B (nb-UVB) was the most effective treatment in reducing pruritus. Biological therapies, mainly etanercept and efalizumab, proved useful in its control.Conclusions: The questionnaire was a useful tool to characterize itch, and the results might help us to better understand pruritus in psoriasis. The results confirmed the need for a global study of psoriasis with regard to both the cutaneous manifestations and the itch symptom.Keywords: itch, psoriasis, pruritus, epidemiology, phototherapy, etanercept, efalizuma

Stage-dependent effects of retinoic acid on regenerating urodele limbs

Following amputation through the distal zeugopodium, regenerating limbs of larvalAmbystoma mexicanum and pre and post-metamorphic Pleurodeles waltlii were treated with 150 μg of retinoic acid (RA) per gram of body weight, at the dedifferentiation, early bud, medium bud, late bud or early redifferentiation stages of regeneration. The effect of RA on regenerate morphogenesis differed as a function of the stage at which it was administered. When given during dedifferentiation or at early bud stages, RA evoked proximodistal duplications of stump segments in the regenerates. The maximum duplication index (DI) in Abystoma was achieved when RA was injected at 4 days post-amputation, which corresponds to the stage of dedifferentiation; and inPleurodeles at 10 days post-amputation, which corresponds to a stage midway between early bud and medium bud. When RA was administered at later stages, the DI declined progressively to zero or nearly zero by the stage of early redifferentiation in both species. The decline in DI was due to a decreased frequency of duplication, not to a decrease in the magnitude of duplication in individual regenerates. At the same time, there was an increase in hypomorphism and aberrant morphogenesis of both duplicating and non-duplicating regenerates. These results indicate that regenerative cells are differentially sensitive to RA in a stage-dependent way