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A pair of nanostructured mirrors made of a diffraction grating inscribed in the top layer of a Bragg mirror are designed such that a phase shift near π and different reflected amplitudes exist between transverse electric (TE) and magnetic (TM) reflected polarization states at normal incidence. When a standing wave laser resonator is formed with two such mirrors and the two mirrors’ principal axes are twisted one with respect to the other, this phase shift condition suppresses multiple longitudinal mode emission arising from axial spatial hole burning. In addition, the different amplitudes of TE and TM reflected polarizations create polarization eigenstates with different round-trip losses, suppressing one polarization eigenstate. Laser experiments made with a Yb3+-doped Y3Al5O12 active material reveal enhanced purity of the emission spectrum compared to similar lasers using conventional laser mirrors. The proposed design enables a miniature single mode laser, replacing more complex designs usually needed to achieve that goal.

Introduction: Atopic dermatitis (AD) is a chronic, inflammatory skin disorder with eczematous and pruritic lesions. Topical moisturisers and either topical corticosteroids or calcineurin inhibitors are usually recommended. Restoring the skin barrier function alleviates AD symptoms. Objective: To evaluate the efficacy of a new moisturiser compared to commercially available products in an AD murine model. Methods: Experimental AD was induced with topical applications of 2,4-DiNitroChloroBenzene (DNCB) on the shaved back skin of BALB/c mice from Day 1 to Day 38. Mice were randomized to either Vehicle/-, DNCB/-, or DNCB/Eczekalm (test product), DNCB/Atopiclair®, or DNCB/Lipikar (reference products) groups. Once daily application of either Eczekalm or Atopiclair® or Lipikar on the AD lesion was performed from Day 32 to Day 38. The AD severity index (ADSI) and animal behaviour were monitored throughout the study. The trans-epidermal water loss (TEWL) was measured on the sacrifice day (Day 39). Results: At Day39, ADSI in the DNCB/Eczekalm, DNCB/Lipikar, and DNCB/Atopiclair® groups were significantly lower by -70%, -68%, and -57%, respectively, as compared to DNCB/- (p Conclusion: Eczekalm treatment significantly reduced the inflammatory effects due to AD and itching episodes and restored the skin barrier function.

The optical properties of thin films are generally determined by direct photometric quantities. We show that additional insight into the properties of anisotropic thin films can be obtained by computing the polarization eigenstates and eigenvalues of their Jones matrices. We consider helically structured thin films, which display intriguing optical response, such as the circular Bragg resonance. Using numerical simulations and actual measurements, we show that the eigenvectors are mutually orthogonal in most regions of the wavevector space, except near the circular Bragg and the oblique resonances. Special wavevector values, called exceptional points, are found where the Jones matrix becomes defective and its eigenvectors coalesce. Exceptional points are also found in pairs of wavevector values differing only by a sample rotation by π around the direction normal to the sample; this property is shown to arise from Saxton - de Hoop’s reciprocity principle, which applies to lossy materials and contains time reversal symmetry, which only applies to lossless materials, as a special case.

A solar-pumped laser (SPL) that converts sunlight directly into a coherent and intense laser beam generally requires a large concentrating lens and precise solar tracking, thereby limiting its potential utility. Here, we demonstrate a fully-planar SPL without a lens or solar tracking. A Nd3+-doped silica fiber is coiled into a cylindrical chamber filled with a sensitizer solution, which acts as a luminescent solar collector. The body of the chamber is highly reflective while the top window is a dichroic mirror that transmits incoming sunlight and traps the fluorescence emitted by the sensitizer. The laser-oscillation threshold was reached at a natural sunlight illumination of 60% on the top window. Calculations indicated that a solar-to-laser power-conversion efficiency could eventually reach 8%. Such an SPL has potential applications in long-term renewable-energy storage or decentralised power supplies for electric vehicles and Internet-of-Things devices. Solar-pumped laser systems are attractive for applications including hydrogen generation and space propulsion, but current technologies are cumbersome and rely on accurate tracking of the sun’s light. Here, lasing is achieved using a planar, luminescent solar collector removing the need for lenses or tracking.

Exceptional points, where the polarization eigenstates of the Jones matrix coalesce into a unique state, were observed in reflection from helically structured thin films. Their application to ultrasensitive detectors or compact single-frequency lasers is discussed.

We show experimentally and theoretically that the phase conjugation of orbital angular momentum (OAM) in cylindrical vector beams does not happen in most regions of the higher-order Poincaré sphere, except near the poles where the beam reduces to a scalar beam and conjugation of OAM may take place.

The polarization states of a resonator made of anisotropic mirrors are shown to coalesce into a single eigenstate at the exceptional point and to eliminate spatial hole burning, thereby promoting single mode laser operation.

Anisotropic mirrors are used to form a laser resonator exhibiting non-Hermitian, parity-time (PT) symmetric, polarization states. The relative angle of the two mirrors principal axes is used to control the degree of non-hermiticity. A sharp symmetry-breaking transition is observed at a specific angle, called the exceptional point, where the two states coalesce into a single polarization state and the interference pattern produced by counter-propagating (CP) waves vanishes. At a smaller angle, in the unbroken PT symmetry regime, the polarization state experiencing higher losses is suppressed. In the broken symmetry regime, the two polarization states coexist, but the orthogonality of the CP waves favors single longitudinal mode emission by suppressing the interference pattern of the standing wave. The two regimes meet at the exceptional point, where a unique polarization state exists in a resonator free from interference intensity pattern. Microchip PT-symmetric lasers operating at the exceptional point are thus an attractive solution to achieve single mode operation from a miniature monolithic device without any intra-cavity element., 29 pages, 5 figures

Helically-structured mirrors producing circular Bragg reflection, used as laser mirrors for the twisted-mode operation of compact single frequency microchip lasers, offer better suppression of dual polarization oscillation than linear birefringent nanostruchrred mirrors.

We demonstrate a solar-powered laser (SPL) that does not rely on any concentrator optics or solar tracking system. We believe that the utility of such “unconcentrated” SPLs has considerably increased for energy conversion applications. The proposed SPL consists of a Nd3+-doped fiber as an active medium, a liquid sensitizer, and a housing in which the transmittance of the front window is tailored to work as a luminescent solar collector. The very simple structure of the proposed SPL can be mass-produced easily at a low cost. The lasing threshold is 0.07 W/cm2 (70% of natural sunlight) which is four orders of magnitude smaller than those of conventional SPLs, and the output power at the pumping intensity of 0.1 W/cm2 is 0.25 mW. The SPL exhibits several lasing peaks between 1095 and 1105 nm.

Exceptional points (EPs) in the polarization space were observed in reflection on helically structured thin films. These films have form anisotropy at the nanoscale introduced through dynamic control of crystalline growth geometry by changing the orientation of the substrate with respect to the impinging vapor. They are simpler alternatives to metasurfaces, because they can be produced at low cost using conventional thin-film deposition techniques. The EPs were experimentally confirmed by eigenstate swapping on a closed circuit surrounding them and were predicted by numerical calculations. Reflective surfaces operating at an EP could be used to make ultrasensitive sensors.

The antihypertensive potential of a land snail by-product hydrolysate (SBH), obtained after an industrial treatment of the raw material, was studied in vitro and in vivo . The ACE inhibitory activity of SBH was characterised by an IC 50 value of 23 µg⋅mL −1 , which was not affected by in vitro digestion. SBH enhanced the Caco-2 intestinal cell metabolic activity and did not induce any toxicity in Wistar rats. The partial purification of SBH led to the obtainment of an active fraction characterised by an IC 50 of 0.007 µg⋅mL −1 . The sequences of the 17 most abundant peptides of the fraction were identified by LC/MS/MS analysis. Seven of them (YG, YA, VY, SF, FG, GF and VW) are known ACE inhibitory peptides. Finally, in vivo study on SHR rats showed that SBH significantly reduced systolic blood pressure. SBH represents therefore a new candidate as an ingredient for the design of functional foods against hypertension.

Multimode laser emission generally takes place in homogeneously broadened gain media placed inside a standing-wave resonator due to spatial hole burning. Solutions proposed to eliminate this phenomenon have so far involved the use of intracavity elements, such as an etalon, wave plates or saturable absorbers. We propose a monolithic solution, wherein birefringent layers of T i O 2 are deposited on both laser mirrors. This solution enables one to control the contrast of the interference pattern of the standing wave inside the resonator, and thus the strength of the spatial hole burning, by rotating one mirror around the optical axis. A monochromatic laser emission is demonstrated in a quasi-continuous-wave laser-diode-pumped Y b 3 + : Y A G laser experiment.

The concept of the twisted-mode laser operation, which suppresses spatial hole burning and produces single-mode operation in a standing-wave resonator, is revisited for the case of optically anisotropic laser mirrors presenting arbitrary birefringent and dichroic properties. Our analysis clarifies the relationship between the mirrors’ optical properties and the proximity of the polarization states of the counterpropagating waves, which determines the contrast of the standing-wave pattern inside the resonator. The intensity of the principal mode and the population of the upper laser level as a function of the pumping rate are then determined analytically, which enables estimates of the slope efficiency and threshold of multimode emission for a given contrast value of the standing wave. The inversion density is found to reach an upper bound as a function of the pumping rate for every value of the contrast except unity. The design rules for anisotropic mirrors to produce single-frequency operation are provided that are less strict than those to achieve pure twisted-mode operation.

Background There is a growing interest in the effects of probiotics for the prevention and treatment of skin diseases due to their immunomodulatory and antiinflammatory properties. Objective To assess a mixture of five bacterial strains in the prevention of chronic skin inflammation in mice. Methods Hairless SKH-1 mice received daily oral treatment with the probiotic mixture at the dose of 1x109 Colony-Forming Unit (CFU)/day (or vehicle) for three weeks. Chronic skin inflammation was induced by repeated applications of 12-O-tetradecanoylphorbol-13- acetate (TPA; control mice received acetone). Macroscopic and microscopic evaluations of skin lesions were performed and serum levels of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, IL-17, IL-22, IL-10 and IL-4 measured at the end of the study. Results Treatment with the probiotic mixture significantly limited the induced chronic skin inflammation at both the macroscopic and microscopic levels. This limitation was consistent with downregulated levels of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, IL- 17 and IL-22) and up-regulated levels of the anti-inflammatory cytokines, IL-10 and IL-4. Conclusion The results suggest that the probiotic mixture tested could help in preserving skin integrity and homeostasis and that its use could be beneficial in dermatological conditions such as atopic dermatitis and psoriasis.

We present the design and experimental characterization of nanostructured laser mirrors aimed at suppressing spatial hole burning (SHB) of a standing wave resonator. The dielectric Bragg mirrors were made by GLancing Angle Physical Vapor Deposition. Two designs are presented. First, helically-nanostructured materials that produce circular Bragg resonance at the wavelength matching the helical period. Second, thick anisotropic coatings deposited on ordinary mirrors, which act as half-wave plates to produce twisted mode laser operation. Both designs enable single longitudinal mode laser operation by suppressing SHB.

Introduction: Clenbuterol has been used to alleviate chronic obstructive pulmonary disease and elicit an anabolic response in muscles. The aim of this study was to determine the influence of muscle mass variation on physical capacities in rats. Methods: The left hindlimbs of Wistar rats were immobilized for 20 days in plantarflexion with a splint and then remobilized for 16 days. The effect of a non-myotoxic dose of clenbuterol during the immobilization period was evaluated. Physical capacities were coordination, free locomotion, grip strength, and bilateral deficit. Results: Immobilization induced a loss of muscle mass, coordination, and strength without any effect on free locomotion. The positive anabolic effect of clenbuterol did not prevent a loss of physical capacities resulting from immobilization. Conclusions: Muscle mass correlated strongly with coordination and isometric strength in untreated rats. Anabolic effect, fiber phenotype modification, and perturbation in neuromuscular communication with clenbuterol improved muscle mass, but it altered physical capacities. Muscle Nerve 52: 1078–1087, 2015

The green seaweed Ulva sp. contains a large amount of ulvans, a family of sulphated polysaccharides. The present study was designed to investigate in rats the antidepressant- and anxiolytic-like effects of a hydrophilic extract of Ulva sp. (MSP) containing about 45% of ulvans.After a 14-day administration of MSP at doses of 10, 20 and 40 mg/kg/day, 48 and 60 male adult Wistar rats were respectively tested in the elevated plus-maze (EPM) and the forced swimming test (FST). In the FST, MSP effects were compared to the reference antidepressant drug imipramine (IMI) (10 mg/kg/day). Acute and sub-chronic toxicities of the extract were also assessed in male and female rats following OECD guidelines.MSP treatment did not modify anxiety-related behaviour in the EPM. In contrast, MSP induced a dose-dependent reduction of immobility behaviour in the FST. At the highest tested dose of 40 mg/kg, MSP displayed a significant antidepressant-like effect similar to IMI. MSP did not modify the exploratory behaviour of rats in the open field test and did not produce any toxic effect.MSP may potentially represent a good adjunct or alternative to existing antidepressant therapeutics. Further studies are necessary to confirm the mechanism of action of MSP and its modulation of brain functioning.

The nanostructure of ytterbium-doped yttrium oxide thin films, produced using pulsed laser ablation of a Yb–Y alloy target together with a pulsed flow of oxygen, is examined using X-ray and electron diffraction as well as Scanning Transmission Electron Microscopy (STEM). As-produced coatings are amorphous and become nanocrystalline cubic yttria after annealing. STEM images taken in the Bright-Field (BF) and in the High-Angle Annular Dark-Field (HAADF) modes reveal different aspects of the nanostructure of yttria. Simulations of the bixbyite structure of yttria indicate that dark spots arranged in a honeycomb structure seen in the STEM-BF mode arise from the absence of oxygen ions at regular crystallographic locations, while those seen on the HAADF images arise from cationic distortions. These results spectacularly exemplify the complementarity of the BF and HAADF imaging modes. Luminescence properties of amorphous and crystalline samples are also studied. Excitation of Yb3+ ions with an infrared (IR) laser diode produce both IR luminescence from excited Yb3+ and visible luminescence from holmium impurities present in the starting materials. Yb3+ emission bands become increasingly narrower as crystallization takes place, testifying for the transition from inhomogeneous to homogeneous crystal field. Increased lifetime and more intense luminescence observed after annealing imply reduced nonradiative relaxation and higher quantum efficiency.

Stress is closely linked by its biological mechanisms to inflammation and by its consequences to accelerated aging. Stress triggers a hormonal response along the hypothalamus-pituitary-adrenal (HPA) axis, which can disrupt the ortho/parasympathetic balance essential for a harmonious life. Proper nutrition, adequate physical activity, and limiting the harmful influence of stress play important roles in avoiding the development of disease and promoting healthy aging. d-Limonene, a monoterpene shown to reduce inflammatory parameters in several pre-clinical and clinical models, could also produce an anti-stress action by altering ortho/parasympathetic parameters as well as central neurotransmitter functions. Here we report on a rat model, where a functional observational battery (FOB) was performed by submitting animals to non-pathological stress. d-Limonene or its metabolite perillyl alcohol (POH) were administered per os at a dose of 10 mg/kg. FOB tests were performed 1 hr before gavage and then at 60, 120, and 180 min. These tests confirmed the stressed status of control rats fed vehicle. Conversely, a series of parameters were significantly less disturbed in treated rats, who retained a better activity and displayed less signs of stress. These effects were more pronounced and sustained after ingestion of d-limonene than POH, suggesting the role of endogeneous metabolization of the terpene. These studies show that d-limonene exerts, through its metabolite POH, a significant anti-stress action measurable by behavioral and physiologic parameters under the influence of the nervous system. In addition to its anti-inflammatory effects, a beneficial role as an anti-stress substance could thus be claimed for d-limonene used as a dietary supplement.

The orange-peel derived terpene d-Limonene, probably through its metabolite, perillyl alcohol (POH), has been reported to have tissue-repair properties. Two murine models of respectively 12-O-Tetradecanoylphorbol-13-Acetate (TPA)-induced dermatitis and mechanical skin lesion were used here to assess the efficacy of d-Limonene or POH applied topically. Macroscopic and microscopic evaluation of skin lesions was performed as well as that of P-selectin expression, together with measurements of serum concentrations of IL-1β, IL-6 and TNF-α in the first model. Healing and angiogenesis around the scar were examined in the second model. Because differences in angiogenesis were noted, the effect of both d-Limonene and POH was further tested on an in vitro model of endothelial microtubules formation. Both d-Limonene and POH reduced the severity and extension of TPA-induced skin lesions with significantly lowered macroscopic and microscopic scores (p

A Monte Carlo ray-tracing simulation was developed for a transversely excited solar-pumped fiber laser without focusing optics. To make this possible, the fiber is immersed in a liquid sensitizer and sandwiched between highly reflective mirrors. The top reflector is dichroic to transmit solar radiation but reflect fluorescence to confine photons that match the absorption band of the active fiber. Simulation was used to evaluate the validity of the concept and optimize device performance. For comparison with the calculations, preliminary experiments were conducted by illuminating a 30 cm aperture, laser module with a solar simulator. The observed gains were in good agreement with the calculations for various conditions, such as sensitizer concentration and mirror reflectivity. Finally, we show that the predicted output power reaches 29 mW when the fiber length is optimized, and it will be enhanced to 150 mW with 0.21% solar-to-laser efficiency under the assumption of a reabsorption-free sensitizer.

The neodymium-doped optical fiber operated at 1.1 μm is a very promising material for the solar-pumped laser without concentrator because of its strong absorption bands in the visible region and its extremely low optical losses. It is generally considered a true four-level system owing to the large energy gap of the lower level of the laser transition to the ground level. In this study, the exquisitely small thermally excited population in the I11/24 Stark level is shown to be primarily responsible for the absorption losses at the laser wavelength at room temperature. Thanks to its long geometry, the absorption cross section and linestrength of the laser transition could be directly measured, allowing easier estimation of the emission cross section than with usual methods relying on fluorescence decay time and quantum efficiency measurements, or a Judd–Ofelt analysis. Our measurements are corroborated by McCumber’s reciprocity principle. The small-signal gain spectrum measured in an amplifier experiment matches well with the emission cross section. Order-of-magnitude loss reduction is demonstrated by lowering the temperature to −34°C, implying substantial reduction of the laser oscillation threshold in cold solar-pumping environments.

The close connection between image formation in geometrical optics and beam transformation by a paraxial optical system is examined analytically using mathematical tools accessible to undergraduate students, such as the Fresnel diffraction integral and Fourier transforms, instead of the more complicated Wigner distribution or coherence functions frequently employed in the literature. It is shown that geometrical optics correctly predicts the plane where a beam is refocused and its magnification only for afocal optical systems or in the limit of point sources. We illustrate this theory by simulating the transformation of a flat-top beam by a pair of lenses.

A study on Laguerre-Gaussian (LG) modes selection in cw and pulsed Nd:YAG or Yb:YAG ceramic lasers pumped by diodes or an external laser source was carried out. Methods of scalar and vector LG modes selection from low to high orders, involving shaping of the pump profile, usage of intra-cavity lenses, uniaxial crystals and polarization selective mirrors, are considered. CCD camera images of beam profiles of hollow scalar LGpm modes (p -radial, m -azimuth indices) of record high-orders and Bessel-like multi-ring modes with highly directional propagation properties are presented. CW and pulsed ceramic lasers with radially or azimuthally polarized LG vector modes of low and high orders are also demonstrated. Applications of the developed laser schemes and LG beams are discussed. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The TLC-Ag dressings, a combination of technology lipido-colloid and silver salts, are used to promote healing in wounds with risks or signs of local infection, thanks to the antimicrobial properties of the silver salts. Nanocrystalline silver dressings containing nanocrystalline silver, also used to improve wound healing, present both antimicrobial and anti-inflammatory effects. The aim of this study was to investigate the anti-inflammatory effects of TLC-Ag dressings in a model of chronic skin inflammation induced by repeated application of 12-O-tetradecanoylphorbol-13-acetate to the skin of hairless mice, in comparison with TLC dressing, Silcryst nanocrystalline dressing, desonide cream 0.05%, a corticoid cream used as positive control, and gauze. Daily treatments of the mice began 7 days after the start of induction of chronic skin inflammation and lasted for 7 days. A macroscopic score was performed daily during the treatment period until the mice killing on day 15 and skin samples were taken for histopathological analysis. TLC-Ag reduced significantly the macroscopic score of chronic skin inflammation from day 10 in comparison with gauze and TLC dressing, similarly to Silcryst nanocrystalline dressing and desonide cream, which presented the best anti-inflammatory effects. No significant differences were observed between TLC dressing and gauze. TLC-Ag reduced significantly the microscopic score of chronic skin inflammation in comparison with TLC dressing and gauze, similarly to Silcryst nanocrystalline dressing but significantly less than desonide cream. These results demonstrate that TLC-Ag dressings present significant anti-inflammatory effects on chronic skin inflammation. They can improve wound healing, due to both the antimicrobial and anti-inflammatory properties.

The increasing prevalence and social burden of subclinical anxiety in the western world represents a significant psychosocial and financial cost. Consumers are favouring a more natural and nonpharmacological approach for alleviating the effects of everyday stress and anxiety. The gamma-aminobutyric acid (GABA) receptor is the primary mediator of central inhibitory neurotransmission, and GABA-receptor agonists are well known to convey anxiolytic effects. Using an in vitro screening approach to identify naturally occurring phytochemical GABA agonists, we discovered the plant secondary metabolite p-coumaric acid to have significant GABAergic activity, an effect that could be blocked by co-administration of the specific GABA-receptor antagonist, picrotoxin. Oral administration of p-coumaric acid to rodents induced a significant anxiolytic effect in vivo as measured using the elevated plus paradigm, in line with the effects of oral diazepam. Given that p-coumaric acid is reasonably well absorbed following oral consumption in man and is relatively nontoxic, it may be suitable for the formulation of a safe and effective anxiolytic functional food.

Chlorella sp. is a green microalgae containing nutrients, vitamins, minerals, and chlorophyll. In some communities, Chlorella sp. is a traditional medicinal plant used for the management of inflammation-related diseases. In a rat model, ROQUETTE Chlorella sp. (RCs) benefits were investigated on visceral pain and associated inflammatory parameters related to cystitis both induced by cyclophosphamide (CYP). RCs was orally administered every day from day 1-16 (250 and 500 mg/kg body weight). Six hours after an intraperitoneal injection of 200 mg/kg body weight of CYP, body temperature, general behavior, food intake, and body weight were recorded. Twenty-four hours after CYP injection, rats were tested in two behavioral tests, an open field and the aversive light stimulus avoidance conditioning test, to evaluate the influence of pain on general activity and learning ability of rats. After euthanasia, bladders were weighed, their thickness was scored, and the urinary hemoglobin was measured. RCs orally administered at the two dosages significantly reduced visceral pain and associated inflammatory parameters related to cystitis both induced by CYP injection, and improved rat behavior. To conclude, RCs demonstrated beneficial effects against visceral pain and cystitis.

Juglans regia L. (walnut) is a plant traditionally used for the treatment of diarrhea. We investigated the antidiarrheal effects of a hydroethanolic leaf extract (HLE) of J. regia against castor oil-induced diarrhea in rats after screening phenolic compounds in the extract. J. regia HLE (0.5, 1, and 2 g/kg by gavage) produced a dose-dependent delay in the onset of diarrhea compared to the vehicle. It also significantly reduced the number of diarrheal feces, fresh weight and water content of the feces, body weight loss and pain at the two highest doses. Loperamide was effective in inhibiting diarrhea and body weight loss but failed to reduce pain. Our findings show that J. regia HLE has a beneficial effect on diarrhea symptoms and associated pain suggesting that it could be an interesting alternative to standard anti-motility drugs. Flavonoids and hydroxycinnamic acids detected in the extract might explain the effects observed.

A polarizing laser mirror made with glancing angle deposition of TiO2 could withstand a train of 2.7 ns pulses with peak power density of around 800 MW/cm2 and a polarization extinction ratio of 1000 when used as an output coupler of a passively Q-switched (Yb0.1Y0.9)3Al5O12 ceramic laser.

Probiotics have been shown to have preventive and therapeutic effects on diarrhea. Because effects tend to be strain specific, benefit of a strain or mixture has to be substantiated by experimental evidence. The aim of this study was to investigate the antidiarrheal and antinociceptive effects of a probiotic mixture (Lactibiane Imedia®, PiLeJe). Castor oil-induced diarrhea test was performed in Wistar rats following oral administration of probiotics (20 × 109, 30 × 109 or 40 × 109 CFU/kg), loperamide (5 mg/kg) or vehicle (water; 10 mL/kg). Time to initial evacuation, number of feces and diarrheal feces, fresh weight and water content of the feces and body weight loss were monitored. Behavioral parameters (eye closing, abnormal posture, activity, fur aspect) were used as pain indices. Probable mechanisms of action were evaluated by using the castor oil-induced enteropooling and charcoal meal transit tests. Probiotics significantly and dose-dependently delayed onset time to first feces and had a beneficial effect on all other parameters (p 90%) at the two highest doses tested (30 × 109 or 40 × 109 CFU/kg) without completely blocking defecation (65.7% at 30 × 109 CFU/kg). Behavioral parameters were improved with probiotics compared to vehicle, improvement that was not observed with loperamide. Probiotics significantly and dose-dependently decreased the volume of intestinal fluid (p

Over the last twenty years, diode pumping of solid-state lasers has opened new prospects for the mode control and formation of Laguerre-Gaussian (LG) beams, enabling a large variety of applications. Experiments on scalar and vector LG modes selection in Nd3+- and Yb3+-doped ceramics and crystal lasers carried out at the Institute for Laser Science, Tokyo are reviewed. Selection of LG modes from low to high orders using intra-cavity elements, polarization-selective mirrors, or shaping the pump beam profile, is considered. Illustrations of record-high-order LG hollow modes, multiring modes with highly directional propagation properties, characteristics of cw and pulsed lasers with radially or azimuthally polarized beams of high polarization purity are presented. General solutions of the wave equation for the axi-symmetric electric field, which describe LG beams of various profiles, are proposed for data analysis. In parallel, a short review on LG modes selection studies carried out at other laboratories is given.

Fluorene is one of the most abundant polycyclic aromatic hydrocarbons (PAHs) in the environment by reason of its high volatility. Demonstrated to be a neurotoxicant through inhalation, it was also identified as a contributive PAH to food contamination. Since no data are available on its oral neurotoxicity, the purpose of the present study was to assess the behavioral and physiological toxicity of repeated oral administration of fluorene to adult Wistar male rats. Animals were daily treated with fluorene at 1, 10 or 100 mg/kg/day for 28 consecutive days. Administration was intraperitoneal (i.p.) or oral (p.o.) to evaluate the influence of the route of exposure on fluorene toxicity. Following this period of treatment, animals in both groups were subjected to similar cognitive evaluations, namely anxiety (elevated-plus maze), locomotor activity (open-field) and learning and memory abilities (eight-arm maze and avoidance test of an aversive light stimulus), as well as physiological measurements. The behavioral testing occurred from the 28th to the 60th day of the experiment during which fluorene treatment continued uninterrupted. At the end of this period, the concentration levels of fluorene and of three of its monohydroxylated metabolites in blood and brain were determined using a GC MS/MS method. The results demonstrated a reduction in rat anxiety level at the lowest doses administered (1 and 10 mg/kg/ day) regardless of the treatment route, whereas locomotor activity and learning abilities remained unchanged. Moreover, a less significant weight gain was noticed in animals i.p.- and p.o.-treated with 100 mg/kg/day during the 28-day period of treatment, which, upon comparison with the three other groups, induced a body weight gap that was maintained throughout the experiment. Significant increases in relative liver weight were also observed in a dose-dependent manner in orally treated rats and only in animal treated i.p. with 100 mg/kg/day. According to the dose, higher concentration levels of fluorene and its monohydroxylated metabolites were measured in blood and brain compartments of i.p.treated rats compared to p.o.-treated animals. In conclusion, fluorene reduced the anxiety level of rats related to dose, treatment route, duration of exposure and blood concentration levels of metabolites.

Seaweed extract of Ascophyllum nodosum, ID-alG™, was evaluated for its chronic effects on weight management in high-fat-fed Sprague-Dawley rats. ID-alG™ was orally administered daily during 9 weeks at doses of 40 and 400 mg/kg/day with fat-enriched diet (FED) in comparison with two control groups consuming standard diet (negative control) or FED (positive control) and orally treated with vehicle. Body weight, percentage of body fat mass and lipid parameters were measured. After 9 weeks, the oral administration of ID-alG™ at both doses decreased significantly the mean body weight gains (MBWG) of rats submitted to the FED in comparison to the positive control (-6.8% and -11.8%). ID-alG™ at both doses improved significantly the MBWG of rats and decreased significantly the percentage of body fat mass of rats (-9.8% and -19.0%), in comparison to the positive control. In the same way, the triglyceride blood level was also significantly improved for the dose of 400 mg/kg/day (-30.6% vs. +49.9% for the positive control); and the dose of 40 mg/kg/day just lead to a trend. Moreover, in both controls and ID-alG™-treated groups, total cholesterol, LDL and HDL blood levels were not modified. The seaweed extract of Ascophyllum nodosum, ID-alG™, demonstrated beneficial effects on weight management of rats submitted to a high-fat diet.

Dehydrated extract of the prickly pear fruit Opuntia ficus indica, Cacti-Nea, was evaluated for its chronic diuretic and antioxidant effects in Wistar rats. Cacti-Nea was orally administered daily for seven days at the dose of 240 mg/kg/day. A positive group was orally treated with hydrochlorothiazide at the dose of 10 mg/kg/day and a control group with vehicle. Daily measurements of body weight, urine volume, and concentration of sodium, potassium and uric acid in urine were performed for each rat. At the end of the study, the blood globular level of glutathione peroxidase was determined. Cacti-Nea significantly increased the urine volumes excreted by rats in comparison with the control group and it showed a trend to reduce significantly the body weight gain of rats. No significant differences were observed in the urine concentration of sodium, potassium and uric acid in comparison with the control group. The chronic diuretic effects of Cacti-Nea were comparable with that of the standard drug hydrochlorothiazide. Chronic oral administration of Cacti-Nea significantly increased the blood globular levels of glutathione peroxidase in comparison with control and hydrochlorothiazide groups. The prickly pear fruit extract Cacti-Nea demonstrated chronic diuretic and antioxidant effects in Wistar rats with respect to the excretion of the metabolites.

Numerous studies have indicated that increased vulnerability to oxidative stress may be the main factor involved in functional declines during normal and pathological ageing, and that antioxidant agents, such as polyphenols, may improve or prevent these deficits. We examined whether 1-year administration of a cocoa polyphenolic extract (Acticoa powder), orally delivered at the dose of 24 mg/kg per d between 15 and 27 months of age, affects the onset of age-related cognitive deficits, urinary free dopamine levels and lifespan in old Wistar-Unilever rats. Acticoa powder improved cognitive performances in light extinction and water maze paradigms, increased lifespan and preserved high urinary free dopamine levels. These results suggest that Acticoa powder may be beneficial in retarding age-related brain impairments, including cognitive deficits in normal ageing and perhaps neurodegenerative diseases. Further studies are required to elucidate the mechanisms of cocoa polyphenols in neuroprotection and to explore their effects in man.

Benign prostatic hyperplasia (BPH) is a non-malignant enlargement of the prostate that results in obstructive lower urinary tract symptoms. Plant extracts are frequently used to treat BPH rather than therapeutics that can cause severe side effects. ACTICOA() (Ba0rry Callebaut France, Louviers, France) powder (AP) is a cocoa polyphenolic extract, and we have shown in a previous study that oral treatment with AP prevented prostate hyperplasia. This study investigated whether AP could improve established prostate hyperplasia using the same testosterone propionate (TP)-induced prostate hyperplasia model in rats. Male Wistar-Unilever rats were randomly divided in four groups of 12 rats: one group injected with corn oil and orally treated with the vehicle (negative control) and three groups injected subcutaneously with TP and orally treated with the vehicle (positive control) or AP at 24 (AP24) and 48 (AP48) mg/kg/day. Treatments started 1 week after the start of the induction of prostate hyperplasia and lasted for 2 weeks. The influence of TP and AP on body weights, food and water consumptions, plasma polyphenolic concentration, and serum dihydrotestoterone (DHT) level of rats was examined. At completion of the study, rats were sacrificed, and the prostates were removed, cleaned, and weighed. The prostate size ratio (prostate weight/rat body weight) was then calculated. TP significantly influenced the body weight gain of the rats and their food and water consumptions, while AP reduced significantly these differences in a dose-dependent manner. AP significantly reduced serum DHT level and prostate size ratio in comparison with positive controls also dose-dependently. In conclusion, AP orally administered was effective for reducing established prostate hyperplasia, especially at the dose of 48 mg/kg/day.

Plant extracts are useful in the management of benign prostatic hyperplasia (BPH). This study investigates whether ACTICOA (Barry Callebaut France, Louviers, France) powder (AP), a cocoa polyphenolic extract, could prevent prostate hyperplasia induced by testosterone propionate (TP) in rats. Male Wistar-Unilever rats were randomly divided in four groups of 12 rats: one negative control group receiving subcutaneous injections of corn oil and treated with vehicle and three groups injected subcutaneously with TP and treated with the vehicle (positive control) or AP at 24 (AP24) and 48 (AP48) mg/kg/day. Treatments were given orally and started 2 weeks before the induction of prostate hyperplasia. The influence of TP and AP on body weights and food and water consumption of rats was examined. On day 36, rats were sacrificed, and the prostates were removed, cleaned, and weighed. The prostate size ratio (prostate weight/rat body weight) was then calculated. TP significantly influenced the body weight gain of the rats and their food and water consumption, while AP at both doses tested reduced significantly these differences. TP significantly increased prostate size ratio (P < .001), and this induced increase was significantly inhibited in AP-treated rats in comparison with positive controls (P < .001) in a dose-dependent manner. We conclude that AP can prevent TP-induced prostate hyperplasia and therefore may be beneficial in the management of BPH.

International audience; Inflammation adversely affects the health of millions of people worldwide, and there is an unmet medical need for better anti-inflammatory drugs. We evaluated the therapeutic interest of mycolactone, a polyketide-derived macrolide produced by Mycobacterium ulcerans. Bacterial production of mycolactone in human skin causes a combination of ulcerative, analgesic, and anti-inflammatory effects. Whereas ulcer formation is mediated by the proapoptotic activity of mycolactone on skin cells via hyperactivation of Wiskott-Aldrich syndrome proteins, analgesia results from neuronal hyperpolarization via signaling through angiotensin II type 2 receptors. Mycolactone also blunts the capacity of immune cells to produce inflammatory mediators by an independent mechanism of protein synthesis blockade. In an attempt to isolate the structural determinants of mycolactone’s immunosuppressive activity, we screened a library of synthetic subunits of mycolactone for inhibition of cytokine production by activated T cells. The minimal structure retaining immunosuppressive activity was a truncated version of mycolactone, missing one of the two core-branched polyketide chains. This compound inhibited the inflammatory cytokine responses of human primary cells at noncytotoxic doses and bound to angiotensin II type 2 receptors comparably to mycolactone in vitro. Notably, it was considerably less toxic than mycolactone in human primary dermal fibroblasts modeling ulcerative activity. In mouse models of human diseases, it conferred systemic protection against chronic skin inflammation and inflammatory pain, with no apparent side effects. In addition to establishing the anti-inflammatory potency of mycolactone in vivo, our study therefore highlights the translational potential of mycolactone core-derived structures as prospective immunosuppressants.

The thermal diffusivity of yttria–zirconia (Y2O3–ZrO2) single crystals, with YO1.5 concentrations in the range of 0–60 mol%, has been determined using a new method that is based on spatially resolved (20 μm) infrared mapping of a modulated thermal field. The decreasing trend of the thermal conductivity (K), as a function of the YO1.5 content (up to 20 mol%), can be described using a model based on a Debye approach that has been modified by introducing a cut-off length for the phonon mean free path. At higher concentrations, K increases, as a result of a possible ordering of the point defects.

We developed a model of orthotopic transplantation of bladder tumor cells in female Fischer rats using a new reproducible technique. After first performing the mechanical abrasion of a portion of the bladder urothelium with an Abrader© inserted transurethrally via a catheter, we administered a suspension of 5–40 × 106 viable AY-27 tumor cells in sterile phosphate-buffered saline to the bladder cavity. This rapidly led to a tumor growth incidence of approximately 100%. The induced bladder tumors grew expansively into the bladder cavity from the surface (mucosa) and gradually invaded the submucosa, muscles, serosa and surrounding tissue (high-stage invasive transitional cell carcinoma). Size and staging were related to the quantity of tumor cells instilled into the bladder cavity. This model matches the characteristics of human bladder tumor more closely than other bladder cancer models induced with tumor cells. Moreover, it presents many advantages: the method is reproducible, tumors grow rapidly, they are directly attached to the bladder surface and they are always located on the bladder wall, in line with the urethra. This proves especially helpful for evaluating chemotherapeutic agents by different means such as in vivo fluorescence spectroscopy, a noninvasive method used in photodynamic therapy, or other methods designed to detect and treat transitional cell carcinoma. © 2002 Wiley-Liss, Inc.

Birefringent TiO2 thin films were characterized using spectroscopic ellipsometry. Ellipsometric data were fitted to a model, taking into account the anisotropic nature of the film and the coherence length of the source being shorter than the thickness of the substrate. Using a conventional gradient-based algorithm often produced a wrong set of optical constants corresponding to a local minimum of the objective function, unless the initial guess was carefully chosen. Using an optimization algorithm inspired by the foraging behavior of ants makes it possible to systematically find that small region in the parameter space where the best solution lies, without a priori knowledge of the optical properties of the sample. The proposed method is especially suitable for samples with unknown optical properties or complex materials, such as anisotropic thin films, for which a large number of parameters are needed to describe them.