Transient Plasma Photonic Crystals for High-Power Lasers.

A new type of transient photonic crystals for high-power lasers is presented. The crystal is produced by counterpropagating laser beams in plasma. Trapped electrons and electrically forced ions generate a strong density grating. The lifetime of the transient photonic crystal is determined by the ballistic motion of ions. The robustness of the photonic crystal allows one to manipulate high-intensity laser pulses. The scheme of the crystal is analyzed here by 1D Vlasov simulations. Reflection or transmission of high-power laser pulses are predicted by particle-in-cell simulations. It is shown that a transient plasma photonic crystal may act as a tunable mirror for intense laser pulses. Generalizations to 2D and 3D configurations are possible.

Adenoviral transfer of human aquaporin-1 gene to rat liver improves bile flow in estrogen-induced cholestasis.

Estrogens can cause liver cholestatic disease. As downregulation of hepatocyte canalicular aquaporin-8 (AQP8) water channels has been involved in estrogen-induced bile secretory failure, we tested whether the archetypal water channel AQP1 improves 17α-ethinylestradiol (EE)-induced cholestasis. EE administration to rats reduced bile flow by 50%. A recombinant adenoviral (Ad) vector encoding human AQP1 (hAQP1), AdhAQP1, or a control vector was administered by retrograde bile ductal infusion. Hepatocyte canalicular hAQP1 expression was confirmed by liver immunostaining and immunoblotting in purified membrane fractions. Accordingly, canalicular osmotic water permeability was markedly increased. Bile flow, either basal or bile salt-stimulated was significantly augmented by over 50%. The choleretic efficiency of endogenous bile salts (that is, volume of bile per µmol of excreted bile salt) was significantly increased by 45% without changes in the biliary bile salt composition. Our data suggest that the adenoviral transfer of hAQP1 gene to the livers of EE-induced cholestatic rats improves bile flow by enhancing the AQP-mediated bile salt-induced canalicular water secretion. This novel finding might have potential therapeutic implications for cholestatic diseases.

Sensory evolution of hearing in tettigoniids with differing communication systems.

In Tettigoniidae (Orthoptera: Ensifera), hearing organs are essential in mate detection. Male tettigoniids usually produce calling songs by tegminal stridulation, whereas females approach the males phonotactically. This unidirectional communication system is the most common one among tettigoniids. In several tettigoniid lineages, females have evolved acoustic replies to the male calling song which constitutes a bidirectional communication system. The genus Poecilimon (Tettigoniidae: Phaneropterinae) is of special interest because the ancestral state of bidirectional communication, with calling males and responding females, has been reversed repeatedly to unidirectional communication. Acoustic communication is mediated by hearing organs that are adapted to the conspecific signals. Therefore, we analyse the auditory system in the Tettigoniidae genus Poecilimon for functional adaptations in three characteristics: (i) dimension of sound-receiving structures (tympanum and acoustic spiracle), (ii) number of auditory sensilla and (iii) hearing sensitivity. Profound differences in the auditory system correlate with uni- or bidirectional communication. Among the sound-receiving structures, the tympana scale with body size, whereas the acoustic spiracle, the major sound input structure, was drastically reduced in unidirectional communicating species. In the unidirectional P. ampliatus group, auditory sensilla are severely reduced in numbers, but not in the unidirectional P. propinquus group. Within the P. ampliatus group, the number of auditory sensilla is further reduced in P. intermedius which lost acoustic signalling due to parthenogenesis. The auditory sensitivity correlated with the size of the acoustic spiracle, as hearing sensitivity was better with larger spiracles, especially in the ultrasonic range. Our results show a significant reduction in auditory structures, shaped by the differing sex roles during mate detection.

[Pharmaceutical therapy of bone metabolism disorders in chronic kidney disease mineral bone disorder (CKD-MBD) with special respect to antiresorptive substances]. / Medikamentöse Therapie von Knochenstoffwechselstörungen bei CKD-MBD ("chronic kidney disease - mineral bone disorder") unter besonderer Berücksichtigung antiresorptiver Wirkstoffe.

Disturbances in bone and mineral turnover are common complications in patients with impaired renal function. Besides an increased risk for cardiovascular events they promote skeletal events, such as bone pain and fractures. Evidence for the antifracture efficacy of antiresorptive and osteoanabolic treatment strategies has only been demonstrated for patients with osteoporosis. The use of osteotropic drugs in patients with impaired renal function requires large randomized placebo-controlled trials.

Molecular and classical chromosomal techniques reveal diversity in bushcricket genera of Barbitistini (Orthoptera).

The cytogenetic characteristics of 17 species of bushcricket belonging to eight genera of the tribe Barbitistini were examined by fluorescence in situ hybridization with 18S rDNA and (TTAGGn) telomeric as probes and by C-banding, silver, and fluorochrome staining. These markers were used to understand chromosomal organization and evolutionary relationships between genera or species within the same genus. The number of 18S rDNA clusters per haploid genome that co-localized with active nucleolus organizer regions (NORs) ranged from one to five, with the most common pattern being the presence of one NOR-bearing chromosome. This ribosomal cistron was preferentially located in the paracentromeric region of autosomes and very rarely in the sex chromosome. The results demonstrated coincidence between the localization of major ribosomal genes and active NORs and the position of C-band and GC-rich regions. The rDNA/NOR distribution and the composition of chromosome heterochromatin proved to be good cytogenetic markers for distinguishing species and phylogenetic lines and for understanding the genomic differentiation and evolution of Barbitistini. A comparison of cytogenetic and morphological or behavioral traits suggests that morphological and behavioral specialization in this group was not followed by major karyotype modification (except for Leptophyes). However, the occurrence and distribution of different repetitive DNA sites tends to vary among the taxa.

Formation and properties of spatially inhomogeneous plasma density gratings.

Volume plasma density gratings receive increasing interest since, compared to solid-state optical media, they posses significantly higher damage thresholds. The gratings are produced by counterpropagating laser pulses in underdense plasma. When analyzing their optical properties, usually they are assumed to be homogeneous in space. The latter assumption, however, breaks down, especially when the gratings are produced by short high-power laser pump pulses. Then, generically the plasma grating posses an inhomogeneous envelope which results from the superposition of the pump pulses envelopes. The present paper discusses the effect of grating inhomogeneity on reflection and transmission of probe pulses. A Gaussian plasma density grating becomes an apodized grating which offers significant improvement over homogeneous gratings due to side-lobe suppression while maintaining reflectivity and a narrow bandwidth. On the other hand, the reflected probe pulses receive a chirp which depends on the spatial scale. For a Gaussian grating a cubic spectral phase appears. Numerical particle-in-cell simulations are supported by theoretical analysis based on coupled mode equations as well as an effective medium approach.

Electrophilic PPARγ ligands inhibit corneal fibroblast to myofibroblast differentiation in vitro: a potentially novel therapy for corneal scarring.

A critical component of corneal scarring is the TGFß-induced differentiation of corneal keratocytes into myofibroblasts. Inhibitors of this differentiation are potentially therapeutic for corneal scarring. In this study, we tested the relative effectiveness and mechanisms of action of two electrophilic peroxisome proliferator-activated receptor gamma (PPARγ) ligands: cyano-3,12-dioxolean-1,9-dien-28-oic acid-methyl ester (CDDO-Me) and 15-deoxy-Δ(-12,14)-prostaglandin J(2) (15d-PGJ(2)) for inhibiting TGFß-induced myofibroblast differentiation in vitro. TGFß was used to induce myofibroblast differentiation in cultured, primary human corneal fibroblasts. CDDO-Me and 15d-PGJ(2) were added to cultures to test their ability to inhibit this process. Myofibroblast differentiation was assessed by measuring the expression of myofibroblast-specific proteins (αSMA, collagen I, and fibronectin) and mRNA (αSMA and collagen III). The role of PPARγ in the inhibition of myofibroblast differentiation by these agents was tested in genetically and pharmacologically manipulated cells. Finally, we assayed the importance of electrophilicity in the actions of these agents on TGFß-induced αSMA expression via Western blotting and immunofluorescence. Both electrophilic PPARγ ligands (CDDO-Me and 15d-PGJ(2)) potently inhibited TGFß-induced myofibroblast differentiation, but PPARγ was only partially required for inhibition of myofibroblast differentiation by either agent. Electrophilic PPARγ ligands were able to inhibit myofibroblast differentiation more potently than non-electrophilic PPARγ ligands, suggesting an important role of electrophilicity in this process. CDDO-Me and 15d-PGJ(2) are strong inhibitors of TGFß-induced corneal fibroblast to myofibroblast differentiation in vitro, suggesting this class of agents as potential novel therapies for corneal scarring warranting further study in pre-clinical animal models.

Increased copulation duration before ejaculate transfer is associated with larger spermatophores, and male genital titillators, across bushcricket taxa.

Copulation duration varies considerably across species, but few comparative studies have examined factors that might underlie such variation. We examined the relationship between copulation duration (prior to spermatophore transfer), the complexity of titillators (sclerotized male genital contact structures), spermatophore mass and male body mass across 54 species of bushcricket. Using phylogenetic comparative analyses, we found that copulation duration was much longer in species with titillators than those without, but it was not longer in species with complex compared with simple titillators. A positive relationship was found between spermatophore size and copulation duration prior to ejaculate transfer, which supports the hypothesis that this represents a period of mate assessment. The slope of this relationship was steeper in species with simple rather than complex titillators. Although the data suggest that the presence of titillators is necessary to maintain long copulation prior to ejaculate transfer, mechanisms underlying this association remain unclear.

[Recurrent choroidal detachment in a patient undergoing hormone therapy for prostate cancer]. / Rezidivierende Aderhautamotio bei einem Patienten mit hormonell therapiertem Prostatakarzinom.

An 85-year-old male patient receiving hormone therapy for prostate cancer and secondary open-angle pseudoexfoliation glaucoma developed peripheral choroidal detachment in both eyes. The patient had been admitted to the eye hospital for clarification of a vascular occlusion in the left eye. Cerebral magnetic resonance imaging could exclude metastases and a cerebral space-occupying lesion as the cause of the ocular findings. The local antiglaucomatous treatment was interrupted and as a result the intraocular pressure normalized and the choroidal detachment receded completely. Patients with prostate cancer who receive hormone therapy should also undergo regular ophthalmological screening including funduscopy and measurment of intraocular pressure.

Color center in amethyst quartz.

Treatment with x-rays increased the intensity of color of natural amethyst up to fivefold, and an electron paramagnetic resonance spectrum was detected. The intensity of the spectrum was proportional to the intensity of the optical absorption near 545 mmicro. The EPR spectrum of the color center corresponded to a positive hole trapped on a substitutional Fe(3+) ion in the quartz structure. We ascribe the color to a charge-transfer transition, Fe(4+) + O(2)- --> Fe(3+) + O(1-).

Plasma volume holograms for focusing and mode conversion of ultraintense laser pulses.

Beating of a broad laser reference beam with a quite general focused object beam inside a plasma volume generates a dynamic plasma hologram. Both beams may be of moderate intensity. The volume hologram can be read out by an ultraintense main beam (of similar structure as the reference beam) producing an object beam replica. For the latter, intensity in the focus may become extremely large. As an application, the possibility of a read-out focused Gaussian laser pulse with intensity of several 10^{19}W/cm^{2} in focus is shown by three-dimensional numerical simulations. Besides the focusing possibility, the hologram may also act as a mode converter for high-intensity laser pulses. Generating a plasma hologram with a focused Laguerre-Gaussian object beam results in a staggered plasma density grating, allowing the production of high-intensity vortex beam replica.

Effects of long-term immobilisation on cortical bone mass after traumatic amputation of the phalanges estimated by digital X-ray radiogrammetry.

UNLABELLED: Osteopenia of the cortical and trabecular bone partition is a common finding after immobilisation. Digital X-ray radiogrammetry (DXR) seems to quantify cortical demineralisation caused by circular saw amputation already few days after accident. INTRODUCTION: The study analyses the extent of demineralisation caused by immobilisation in patients with digital amputation after a circular saw injury, and elucidates the period of time which discloses a significant deprivation of bone mineral density estimated at the metacarpalia II-IV using DXR. METHODS: Twenty-eight patients with digital amputations underwent measurements of bone mineral density, cortical thickness, bone width and metacarpal index using DXR-technology in a follow-up up to 902 days. RESULTS: The data showed a significant decline of bone mineral density (-10.47%), the metacarpal index (-4.38%), the bone width (-12.06%) and the cortical thickness (-7.04%) after trauma-related amputation. The cortical demineralisation of the metacarpals could already be revealed in two patients after the second day, according to the amputation of phalanges (-3.65%). CONCLUSIONS: The inhibition of the periosteal bone formation detected by DXR-technique seems to be a specific finding caused by amputation, which thus differs from normal age-related (i.e., endosteal) bone loss and from demineralisation following acute immobilisation (i.e., trabecular osteopenia).

Bone histomorphometry and biochemical markers of bone turnover in patients with chronic kidney disease Stages 3 - 5.

AIMS: Precise identification of renal osteodystrophy requires bone histomorphometry. Several markers of bone turnover may be useful to predict classification and severity of renal osteodystrophy, but there are only limited data whether these markers correlate with bone histomorphometry. METHODS: In 36 patients with chronic kidney disease (CKD) Stage 3/4 and in 96 patients with CKD Stage 5 bone histomorphometry was performed and renal osteodystrophy was classified according to the standardized international nomenclature. Blood samples were taken at the time of bone biopsy, stored and analyzed at the end of the study. RESULTS: Osteitis fibrosa (OF) was the most frequent histomorphometric form, occurred in 47.2% in CKD Stages 3 - 4 and in 61.4% in CKD Stage 5. There was no difference in the frequency of adynamic renal bone disease (ARBD). The correlation coefficients between bone turnover markers and histomorphometric parameters were higher in CKD 5 patients with high bone turnover lesions. The predictive value for high versus low/normal bone turnover status was comparable for alkaline phosphatase (APH), bone alkaline phosphatase (BAP), pyridinoline (Pyd), desoxypyridinoline (Dpyd), tartrat-resistent acid phosphatase (TRAP Vb) and parathyroid hormone (PTH) in CKD Stage 5 patients, but was insufficient for APH and TRAP Vb in CKD Stage 3 - 4 patients. CONCLUSIONS: Besides parathyroid hormone, biochemical parameters of bone turnover provide a moderate discrimination and prediction of bone turnover status only in patients with CKD Stage 5. Due to a large variability, they are of limited use in predicting the histomorphometric type of renal osteodystrophy. Bone histology remains necessary for an exact classification of underlying pathology.

Plasma-based polarizer and waveplate at large laser intensity.

A plasma photonic crystal consists of a plasma density grating which is created in underdense plasma by counterpropagating laser beams. When a high-power laser pulse impinges the crystal, it might be reflected or transmitted. So far only one type of pulse polarization, namely the so-called s wave (or TE mode) was investigated (when the electric field vector is perpendicular to the plane of incidence). Here, when investigating also so-called p waves (or TM modes, where the magnetic field vector is perpendicular to the plane of incidence), it is detected that the transmission and reflection properties of the plasma photonic crystal depend on polarization. A simple analytic model of the crystal allows one to make precise predictions. The first conclusion is that in some operational regime the crystal can act as a plasma polarizer for high-intensity laser pulses. Also, differences in phase velocities for grazing incidence between s and p polarization are found. Thus, secondly, the crystal can be utilized as a waveplate, e.g., transforming linearly polarized laser light into circular polarization. All these processes extend to laser intensities beyond the damage intensities of so far used solid state devices.

Soluble receptor activator of NFkappa B-ligand and osteoprotegerin in rheumatoid arthritis - relationship with bone mineral density, disease activity and bone turnover.

The aim of our study was to investigate determinants of bone mineral density (BMD) measured by dual X-ray absorptiometry at the lumbar spine (BMD-LS) and at the femoral neck (BMD-FN) in patients with rheumatoid arthritis (RA) with special respect to bone resorbing proinflammatory cytokines and their physiological antagonists. In 142 RA patients the following parameters were measured in parallel with BMD: serum levels of soluble receptor activator of nuclear factor kappa-B-ligand (sRANKL), osteoprotegerin (OPG), interleukin (IL)-6, soluble glycoprotein 130 (sgp130), 25-hydroxyvitamin D3 (25OHD(3)), 1,25-dihydroxyvitamin D3 (1,25[OH](2)D(3)), intact parathyroid hormone, osteocalcin, ionized calcium, renal excretion of pyridinolin and deoxypyridinolin, C-reactive protein, and erythrocyte sedimentation rate (ESR). No significant differences of sRANKL, OPG, IL-6, and spg130 were found between patients with osteoporosis (47.9% of patients), osteopenia (36.6%), and normal BMD (15.5%). However, total sRANKL was significantly higher in postmenopausal women with osteoporosis at FN than in those without (p < 0.05) and showed a negative correlation with BMD-LS in patients older than 60 years (p = 0.01). BMD-LS and BMD-FN (p < 0.001) and total sRANKL (p < 0.01) were negatively related with the age of the patients. Only IL-6 (positive correlation, p < 0.001) and 1,25(OH)(2)D(3) (negative correlation, p < 0.001) but not sRANKL, OPG, and sgp130 were related to disease activity. Using multiple linear regression analysis, menopause was identified as the crucial negative determinant of BMD-LS (R (2) = 0.94, p = 0.001), whereas cumulative glucocorticoid dose (beta = -0.80, p = 0.001) and ESR (beta = -0.44, p = 0.016) were the negative determinants of BMD-FN (R (2) = 0.86, p = 0.001). The results indicate that influences of age and gender must be considered in investigations on the relationship between BMD and sRANKL in RA and that high serum levels of sRANKL seems to be associated with osteoporosis only in subgroups of RA patients.

Renal osteodystrophy after successful renal transplantation: a histomorphometric analysis in 57 patients.

Renal transplantation is the treatment of choice for patients with end-stage renal disease. It corrects most of the metabolic abnormalities that cause renal osteodystrophy. Nevertheless, renal osteodystrophy persists in many transplant recipients. The aim of this study was to investigate frequency and histomorphometric pattern of bone disease after renal transplantation. Bone biopsy specimens were taken from the iliac crest of 57 patients, including 28 women (26-70 years old) and 29 men (27-67 years old). Indications for biopsy were hypercalcemia, elevation of parathyroid hormone, and, in 19 cases, without suspected bone abnormalities based on laboratory parameters. The mean time of dialysis prior to renal transplantation was 43 months (range, 6-91 months in women and 10-111 months in men) and the mean interval between transplantation and bone biopsy was 53.5 months (range, 4-191 months in women and 5-90 months in men). Fourteen patients were treated with either 25-hydroxyvitamin D3 and/or 1-alpha hydroxyvitamin D3 or 1,25 dihydroxyvitamin D3, 3 with phosphate-binding agents. The immunosuppression consisted of cyclosporine, azathioprine, and prednisolone. The cumulative dosage of corticosteroids was 5569+/-5305 mg. For static and dynamic histomorphometry, we used American Society of Bone and Mineral Research nomenclature. Mild osteitis fibrosa and osteitis fibrosa, the most frequent forms of renal osteodystrophy, were observed in 13. (22.8%) and 14 patients (24.6%), respectively. Mixed uremic osteodystrophy was found in 7 patients (12.3%), adynamic renal bone disease in 3 patients (5.3%), and osteomalacia in 2 patients (3.5%). In 13 patients (22.8%), reduced bone mass and structural damage without typical signs of renal osteodystrophy, such as endosteal fibrosis or osteoclasia, were detected, and 5 patients (8.7%) showed normal histomorphometric parameters. We concluded that renal osteodystrophy, especially forms with high bone turnover, persisted in many patients after successful renal transplantation. This finding may be due to preexisting conditions, such as duration of dialysis and degree of hyperparathyroidism. Bone disease is increased by corticosteroid and immunosuppressive therapy after renal transplantation and requires close monitoring.

Prevention of early loss of bone mineral density after liver transplantation by prostaglandin E1.

INTRODUCTION: As a result of preexisting chronic liver disease and immunosuppression, the majority of liver transplant patients develop bone mineral density (BMD) loss in the first 3 to 6 months posttransplantation, leading to an increased fracture risk. Using basic prophylaxis and treatment by administration of vitamin D, calcium, and bisphosphonates, BMD loss may be controlled in the long term. In contrast, there is no established medical concept for prevention of early posttransplant BMD loss. MATERIAL AND METHODS: The aim of this trial was to evaluate the effect of prostaglandin E1 on BMD after liver transplantation. Between 1998 and 2004, 29 patients were enrolled in this study. BMD measurement was performed at lumbar spine and femoral neck using dual energy x-ray absorptometry pretransplant, and 3, 6, 12, and 24 months posttransplant. All patients received calcium and vitamin D as basic prophylaxis. In 13 patients, prostaglandin E1 (PGE) was additionally administered for 12 days posttransplant. RESULTS: BMD loss was significantly lower at 3 and 6 months posttransplant in the PGE group (lumbar spine, P < .03; femoral neck, P < .009). Development of BMD loss was comparable between both groups during further follow-up. In the PGE group there was a significantly lower fracture rate compared with the controls (P < .02). CONCLUSION: The application of PGE 1 proved to be beneficial in compensating the early posttransplant BMD loss and in subsequently reducing fracture rate. These positive effects of PGE 1 could be demonstrated in both the femoral neck and lumbar spine.

Bioequivalence comparison between hydroxyethyl starch 130/0.42/6 : 1 and hydroxyethyl starch 130/0.4/9 : 1.

OBJECTIVE: The aim of this study was to investigate whether a recently developed low molecular, low substituted hydroxyethyl starch (HES 130/0.42/6 : 1), altered in molar substitution and C2/C6 ratio, is bioequivalent to the former standard HES preparation (130/0.4/9 : 1). METHODS: The two HES solutions were infused (60g as a single dose within 30 minutes) in healthy volunteers using a randomised, crossover design. HES serum concentrations were used for computation of pharmacokinetic parameters; area under the concentration-time curve from infusion start until 24 hours thereafter (AUC(24)) and maximum serum concentration (C(max)) were the primary criteria. Haemodilution, colloid osmotic pressure and plasma viscosity were measured as secondary criteria. Pentastarch (HES 200/0.5/5:1) was investigated in the same volunteers and manner during a subsequent period. RESULTS: Using non-compartmental analysis, significant differences were found for AUC(24) (45.97 +/- 8.97 mg . h/mL vs 58.32 +/- 9.23 mg . h/mL; HES 130/0.42/6 : 1 vs HES 130/0.4/9 : 1) and total apparent clearance (CL; 1.14 +/- 0.4 L/h vs 0.81 +/- 0.34 L/h). C(max) and elimination half-life (t(1/2)) were similar, while the AUC(24), t(1/2) and CL of pentastarch were significantly different from those of low substituted HES solutions. CONCLUSION: Being equivalent with pentastarch and HES 130/0.4/9 : 1 in terms of colloid osmotic and haemodilution effect, HES 130/0.42/6 : 1 shows the fastest clearance from the circulation.