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This paper deals with ionic species migration based on classical mass balance equations in conjunction with a charge balance equation and the electroneutrality condition. Two new methods are proposed to apply the electroneutrality condition, avoiding the elimination of one of the conservation equations of chemical species and permitting to explicitly apply boundary conditions on all species. The first method is based on variational principles and the second on a Lagrange multiplier. It is shown that the new methods are analytically equivalent to the more standard method in which one conservation equation is eliminated without any other consideration. The variational method is more complex to implement than the Lagrange multiplier method. The new methods were applied to a multi-ionic problem together with the charge conservation equation without capacitive effects. Different kinds of boundary conditions were applied: Neumann, Dirichlet and a nonlinear case based on Butler-Volmer kinetics. All methods gave the same results for non-complex problems. In the case of complex problems including chemical equilibrium between each ionic species, it was found that more investigations are necessary even for more conventional methods. [ABSTRACT FROM AUTHOR]

Gas diffusion in nanofibrous and microfibrous materials is of great interest in microfluidics. In this work, an analytical model is proposed, based on fractal theory, to quantify gas diffusion across fibrous media composed of nanofibers and microfibers. The fractal model is expressed in terms of pore area and tortuosity fractal dimensions, allowing statistical quantification of the geometrical structures of fibrous media. Knudsen diffusion in nanoscale pores is considered. To validate this model, moisture vapor diffusion rate through electrospun nanofibrous webs was measured using the inverted-cup method. The diffusivities predicted from the proposed model agree well with the experimental measurements in the present investigation and those reported in the literature for effective diffusivities of gas diffusion layers in fuel cells. Based on the model, the effect of porosity, fiber radius, and the ratio between the minimum and the maximum pore sizes on the effective diffusivity is analyzed. [ABSTRACT FROM AUTHOR]

We show that the coercivity of electrochemically grown cobalt nanowires (NWs) within the pores of a polycarbonate membrane can be changed to a large extent by tuning their diameters. The face centered cubic crystalline structure of the NWs having diameter in the range of 10 to 200 nm could be retained. Smaller diameter wires (below 30 nm) are found to be single crystalline and oriented in the [110] growth direction, but for higher diameter wires the crystallite size became very small. Magnetization measurements with an applied field parallel to the axis of the NWs show that the nature of the M- H loop changes from square to linear as the diameter of the NWs increases. The coercivity was found to be 1700 Oe and 480 Oe at 5 K (1000 Oe and 250 Oe at 300 K) for 10 nm and 100 nm wires, respectively. The observed changes in the nature of the M- H loop and in coercivity could be explained following the Stoner-Wohlfarth model and using the fact that the domain size reduces as the diameter of the wires increases. [ABSTRACT FROM AUTHOR]

Proton conductive inorganic-organic hybrid membranes were synthesized from Epoxycyclohexylethyltrimethoxysilane (EHTMS) and 1-hydroxyethane-1,1-diphosphonic acid (HEDPA) by the sol-gel method. In this paper, the effect of gel temperature, membrane-forming temperature and Si/P on hybrid membranes performance were discussed. FT-IR studies revealed the phosphonic acid was chemically bonded to the siloxane network. When the membrane-forming temperature is 150 °C, thermal analysis including TG and DTG confirmed that the hybrid membranes were thermally stability up to 250 °C and SEM images showed that the membranes surface smooth and dense, eliminating the phase separation phenomenon. The hybrid membranes with a molar ratio of Si/P = 6/1 possess better thermal stability and preferable flexibility. [ABSTRACT FROM AUTHOR]

Background and Purpose: To compare the efficacy of two different dose-fractionation schedules for radiotherapy of patients with benign painful shoulder syndrome.Patients and Methods: Between February 2006 and February 2010, 312 consecutive evaluable patients were recruited for this prospective randomized trial. All patients received radiotherapy with an orthovoltage technique. One radiotherapy course consisted of 6 single fractions in 3 weeks. In case of insufficient remission of pain after 6 weeks, a second radiation series was performed. Patients were randomly assigned to receive either single doses of 0.5 or 1.0 Gy. The endpoint was pain reduction. Pain was measured before, right after, and 6 weeks after radiotherapy using a visual analogue scale (VAS) and a comprehensive pain score (CPS).Results: The overall response rate for all patients was 83% directly after and 85% 6 weeks after radiotherapy. The mean VAS values before, directly after, and 6 weeks after treatment for the 0.5 and 1.0 Gy groups were 56.8 ± 23.7 and 53.2 ± 21.8 (p = 0.158), 38.2 ± 26.1 and 34.0 ± 24.5 (p = 0.189), and 33.0 ± 27.2 and 23.7 ± 22.7 (p = 0.044), respectively. The mean CPS before, directly after, and 6 weeks after treatment was 9.7 ± 3.0 and 9.5 ± 2.7 (p = 0.309), 6.1 ± 3.6 and 5.4 ± 3.6 (p = 0.096), 5.3 ± 3.7 and 4.1 ± 3.7 (p = 0.052), respectively. Despite a slight advantage in the VAS analysis for the 1.0 Gy group for delayed response, the CPS analysis revealed no statistically significant differences between the two single-dose trial arms for early (p = 0.652) and delayed response quality (p = 0.380).Conclusion: Radiotherapy is an effective treatment option for the management of benign painful shoulder syndrome. Concerning radiation protection, the dose for a radiotherapy series is recommended not to exceed 3-6 Gy. [ABSTRACT FROM AUTHOR]

A high prevalence of intersex or testicular oocytes (TO) in male smallmouth bass within the Potomac River drainage has raised concerns as to the health of the river. Studies were conducted to document biomarker responses both temporally and spatially to better understand the influence of normal physiological cycles, as well as water quality and land-use influences. Smallmouth bass were collected over a 2-year period from three tributaries of the Potomac River: the Shenandoah River, the South Branch Potomac and Conococheague Creek, and an out-of-basin reference site on the Gauley River. The prevalence of TO varied seasonally with the lowest prevalence observed in July, post-spawn. Reproductive maturity and/or lack of spawning the previous spring, as well as land-use practices such as application of manure and pesticides, may influence the seasonal observations. Annual, seasonal, and site differences were also observed in the percentage of males with measurable concentrations of plasma vitellogenin, mean concentration of plasma vitellogenin in females, and plasma concentrations of 17β-estradiol and testosterone in both sexes. Bass collected in the South Branch Potomac (moderate to high prevalence of TO) had less sperm per testes mass with a lower percentage of those sperm being motile when compared to those from the Gauley River (low prevalence of TO). An inverse relationship was noted between TO severity and sperm motility. An association between TO severity and wastewater treatment plant flow, percent of agriculture, total number of animal feeding operations, the number of poultry houses, and animal density within the catchment was observed. [ABSTRACT FROM AUTHOR]

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Karakaya and Sultansuyu Dam Lakes, located in the eastern part of Turkey, are important water sources, both for irrigation and fishery. The main goal of the study was to investigate water qualities of dam lakes using a set of biomarkers in the fish Cyprinus carpio. For this aim, field sample and laboratory-acclimated fish were compared to identify changes in selected biomarkers. The activities of ethoxyresorufin- O-deethylase, glutathione S-transferase, glutathione reductase, and carboxylesterase were determined in liver samples. Also, plasma and liver lactate dehydrogenase, aspartate aminotransferase, and alanine aminotransferase activities were assayed. Brain acetylcholinesterase and carboxylesterase activities were also determined. The hepatosomatic index and condition factors were calculated. Plasma vitellogenin assays were evaluated for the presence of xenoestrogen. Physicochemical values of water samples showed the existence of eutrophication risk, and also, some chemicals in both lakes were determined to be over tolerable limits. The comparisons of samples from both dam lake and laboratory-acclimated fish showed that the lakes may be at risk of pollution by some xenobiotics, namely xenoestrogens and acetylcholinesterase-inhibiting agents. [ABSTRACT FROM AUTHOR]

Recently, the Device for Intervertebral Assisted Motion (DIAMTM) has been introduced for surgery of degenerative lumbar disc diseases. The authors performed the current study to determine the survivorship of DIAMTM implantation for degenerative lumbar disc diseases and risk factors for reoperation. One hundred and fifty consecutive patients underwent laminectomy or discectomy with DIAMTM implantation for primary lumbar spinal stenosis or disc herniation. The characteristics of the 150 patients included the following: 84 males and 66 females; mean age at the time of surgery, 46.5 years; median value of followup, 23 months (range 1 −48 months); 96 spinal stenosis and 54 disc herniations; and 146 one-level (115, L4 −5; 31, L5 −6) and 4 two-level (L4 −5 and L5 −6). In the current study, due to lumbosacral transitional vertebra (LSTV) L6 meant lumbarization of S1 and this had a prominent spinous process so that the DIAMTM was implanted at L5 −6. Reoperations due to any reasons of the DIAMTM implantation level or adjacent levels were defined as a failure and used as the end point for determining survivorship. The cumulative reoperation rate and survival time were determined via Kaplan-Meier analysis. The log-rank test and Cox regression model were used to evaluate the effect of age, gender, diagnosis, location, and level of DIAMTM implantation on the reoperation rate. During a 4-year follow- up, seven patients (two males and five female) underwent reoperation at the DIAMTM implantation level, giving a reoperation rate of 4.7%. However, no patients underwent reoperation for adjacent level complications. The causes of reoperation were recurrent spinal stenosis (n = 3), recurrent disc herniation (n = 2), post-laminectomy spondylolisthesis (n = 1), and delayed deep wound infection (n = 1). The mean time between primary operation and reoperation was 13.4 months (range 2 −29 months). Kaplan-Meier analysis predicted an 8% cumulative reoperation rate 4 years post-operatively. Survival time was predicted to be 45.6 ± 0.9 months (mean ± standard deviation). Based on the log-rank test, the reoperation rate was higher at L5 −6 (p = 0.002) and two-level (p = 0.01) DIAMTM implantation compared with L4 −5 and one-level DIAMTM implantation. However, gender (p = 0.16), age (p = 0.41), and diagnosis (p = 0.67) did not significantly affect the reoperation rate of DIAMTM implantation. Based on a Cox regression model, L5 −6 [hazard ratio (HR), 10.3; 95% CI, 1.7 −63.0; p = 0.01] and two-level (HR, 10.4; 95% CI, 1.2 −90.2; p = 0.04) DIAMTM implantation were also significant variables associated with a higher reoperation rate. Survival time was significantly lower in L5 −6 (47 vs. 22 months, p = 0.002) and two-level DIAMTM implantation (46 vs. 18 months, p = 0.01) compared with L4 −5 and one-level DIAMTM implantation. The current results suggest that 8% of the patients who have a DIAMTM implantation for primary lumbar spinal stenosis or disc herniation are expected to undergo reoperation at the same level within 4 years after surgery. Based on the limited data set, DIAMTM implantation at L5 −6 and two-level in patients with LSTV are significant risk factors for reoperation. [ABSTRACT FROM AUTHOR]

The effect of feeding behaviour on the prey capture efficiency of young-of-the-year European perch and roach was investigated in laboratory experiments using planktonic crustaceans possessing different escape abilities- Daphnia sp. and Cyclops sp. Two sets of experiments were performed. In the first set, the feeding efficiency and behaviour of 270 fish individuals were determined by stomach content analyses and video record evaluations. In the second set of experiments, analysis of attack-effort, which was evaluated as attack-distance and repeated strikes, was undertaken. Except for situations in which Daphnia was offered at high densities, the feeding efficiency of perch was significantly higher compared to roach in all other combinations of prey types and densities. Roach consumed significantly less prey compared to perch when feeding exclusively on the evasive Cyclops and when it was offered in a 1:1 ratio mixture with Daphnia. The mean swimming speed was similar in both fish species, but behavioural differences were evident during prey search and capture. Perch swam through the aquaria in short and fast movements that were interrupted by many stops. Roach exhibited rather continuous swimming that was punctuated by slowdowns instead of stops. The perch attacks were very intensive and repeated strikes occurred, particularly when feeding on evasive Cyclops. On the other hand, roach revealed strong schooling behaviour restricting the fish during inspection of the experimental aquaria. The distinct differences in feeding efficiency between perch and roach were demonstrated to be closely related to differences in their feeding behaviour. Discontinuous searching for prey, vigorous attacks, occurrence of repeated strikes and the absence of schooling increased perch prey capture efficiency, particularly when foraging on evasive copepods. [ABSTRACT FROM AUTHOR]

The third and final part of a review on the extraction of noble metals by macrocyclic compounds, which is devoted to extraction with O-, S-, and N-containing calyxarenes with a generalization of References from 1978 to 2008, is presented. it is noted that no systematic investigations on the extraction of noble metals with calixarenes has been performed until now. most works are qualitative and do not consider the regularities of the influence of the compositions of aqueous and organic phases and the properties of the extractant on the degree of metal extraction. the studied solutions are unlike production ones in regards to composition, and the chemical state of extracted ions in aqueous solutions is not always taken into account. it is emphasized that there is only fragmentary information on reextraction in the literature. the problem of the selectivity of extraction of noble metals with calixarene esters is discussed. [ABSTRACT FROM AUTHOR]

The rhadinovirus herpesvirus saimiri (HVS) as a gene delivery vector allows large DNA insertions and long-termed gene expression. In the case of T-cell transduction, such vectors use the viral transformation-associated genes of HVS C488 for T-cell amplification. In this report, we investigated whether the gene for the catalytic telomerase subunit human telomerase reverse transcriptase (hTERT) can substitute for the transformation-associated genes in rhadinoviral T-cell transduction and amplification. By using virus mutants generated by en passant mutagenesis from bacterial artificial chromosomes, we observed a very early and functional transgene expression even by virus mutants without transformation-associated genes. The markers of T-cell transformation by HVS, namely CD2 hyperreactivity, overexpression of interleukin-26, and of the tyrosine kinase Lyn could neither be induced nor enhanced by ectopic hTERT expression. When the viral transformation-associated genes were replaced by the hTERT gene, it was not sufficient for growth transformation, although hTERT was efficiently transduced and functionally expressed by the rhadinovirus vector. Thus, the transformation-associated proteins StpC and Tip are responsible for the T-cell phenotype after transduction by HVS and, additionally, modulate telomerase activity independently of hTERT expression. [ABSTRACT FROM AUTHOR]

Extraction of microamounts of U(VI) and Th(IV) from HNO3 solutions in the form of complexes with polyfunctional organophosphorus acids was studied. The influence of the extractant structure on the efficiency and selectivity of the extraction of U(VI) and Th(IV) was examined, and the stoichiometry of the extractable complexes was determined. The possibility of preconcentration of U(VI), Th(IV), and REE(III) from nitric acid solutions with a complexing sorbent prepared by noncovalent immobilization of bis[2-(diphenylphosphinyl) phenoxymethyl]phosphinic acid on a macroporous polymeric matrix was demonstrated. [ABSTRACT FROM AUTHOR]

Organochlorine chemical residues and elemental concentrations were measured in piscivorous and benthivorous fish at 111 sites from large U.S. river basins. Potential contaminant sources such as urban and agricultural runoff, industrial discharges, mine drainage, and irrigation varied among the sampling sites. Our objectives were to provide summary statistics for chemical contaminants and to determine if contaminant concentrations in the fish were a risk to wildlife that forage at these sites. Concentrations of dieldrin, total DDT, total PCBs, toxaphene, TCDD-EQ, cadmium, chromium, mercury, lead, selenium, and zinc exceeded toxicity thresholds to protect fish and piscivorous wildlife in samples from at least one site; most exceedences were for total PCBs, mercury, and zinc. Chemical concentrations in fish from the Mississippi River Basin exceeded the greatest number of toxicity thresholds. Screening level wildlife risk analysis models were developed for bald eagle and mink using no adverse effect levels (NOAELs), which were derived from adult dietary exposure or tissue concentration studies and based primarily on reproductive endpoints. No effect hazard concentrations (NEHC) were calculated by comparing the NOAEL to the food ingestion rate (dietary-based NOAEL) or biomagnification factor (tissue-based NOAEL) of each receptor. Piscivorous wildlife may be at risk from a contaminant if the measured concentration in fish exceeds the NEHC. Concentrations of most organochlorine residues and elemental contaminants represented no to low risk to bald eagle and mink at most sites. The risk associated with pentachloroanisole, aldrin, Dacthal, methoxychlor, mirex, and toxaphene was unknown because NOAELs for these contaminants were not available for bald eagle or mink. Risk differed among modeled species and sites. Our screening level analysis indicates that the greatest risk to piscivorous wildlife was from total DDT, total PCBs, TCDD-EQ, mercury, and selenium. Bald eagles were at greater risk to total DDT and total PCBs than mink, whereas risks of TCDD-EQ, mercury, and selenium were greater to mink than bald eagle. [ABSTRACT FROM AUTHOR]

The Interstellar Boundary Explorer (IBEX) mission will provide maps of energetic neutral atoms (ENAs) originating from the boundary region of our heliosphere. On IBEX there are two sensors, IBEX-Lo and IBEX-Hi, covering the energy ranges from 10 to 2000 eV and from 300 to 6000 eV, respectively. The expected ENA signals at 1 AU are low, therefore both sensors feature large geometric factors. In addition, special attention has to be paid to the various sources of background that may interfere with our measurement. Because IBEX orbits the Earth, ion, electron, and ENA populations of the Earth’s magnetosphere are prime background sources. Another potential background source is the magnetosheath and the solar wind plasma when the spacecraft is outside the magnetosphere. UV light from the night sky and the geocorona have to be considered as background sources as well. Finally background sources within each of the sensors must be examined. [ABSTRACT FROM AUTHOR]

Inorganic–organic membranes are characterised by the presence of a certain amount of inorganic solid within an organic polymer that serves as the matrix component. From its origins some 15 years ago as a means of conferring proton conduction properties to an insulating polymer matrix by addition of a powdered inorganic proton conductor, the methods of preparation have developed and currently include a range of approaches that allow control over the localisation of the inorganic component preferentially in the hydrophilic or hydrophobic regions of an ionomer, and incite development of morphologies ranging from nanoparticulate to extended network forms. The presence of an inorganic phase is effective in enhancing interaction between components, in limiting dimensional change and in improving fuel cell performance under high temperature, low relative humidity conditions. These approaches have enabled the field to develop from the stage of different concepts of inorganic–organic fuel cell membranes to their implementation in fuel cell stacks. Novel approaches make use of further degrees of organisation of the organic and inorganic components, for example by use of nanoporogens or bimodal/spinodal transformations. [ABSTRACT FROM AUTHOR]

Fabry disease is an inborn error of glycolipid catabolism resulting from lesions in the gene encoding α-galactosidase (GLA). To elucidate the basis of Fabry disease, we constructed structural models of mutant GLAs responsible for the disease and calculated indexes, i.e., the numbers of atoms affected in the main chain and side chain of each mutant GLA, the root-mean-square distance values, and the solvent-accessible surface-area values, based on 212 Fabry amino acid substitutions previously reported (196 classic and 16 variant). As two therapeutic options, enzyme replacement and enzyme enhancement, are now available for this disease, proper prediction of the natural outcome and therapeutic efficiency based on the molecular evidence for individual cases are critical for patients’ quality of life. Our results revealed that structural changes in the classic Fabry group were generally large and tended to be in the core region of a protein or located in the functionally important region, including the active-site pocket. On the other hand, structural changes in the variant Fabry group were small or localized on the surface of the molecule far away from the active site. We focused on structural changes due to amino acid substitutions for which substrate analogues are effective for improving the stability or transportation of mutant GLAs, and the results of the study revealed that they are small or localized on the molecular surface, regardless of the phenotype. Coloring of affected atoms based on distances between wild type and mutant ones clearly showed the characteristic structural changes in the GLA protein geographically and subquantitatively. Structural investigation is useful for elucidation of the basis of Fabry disease and predicting disease outcome. [ABSTRACT FROM AUTHOR]

Membrane fusion can occur between cells, between different intracellular compartments, between intracellular compartments and the plasma membrane and between lipid-bound structures such as viral particles and cellular membranes. In order for membranes to fuse they must first be brought together. The more highly curved a membrane is, the more fusogenic it becomes. We discuss how proteins, including SNAREs, synaptotagmins and viral fusion proteins, might mediate close membrane apposition and induction of membrane curvature to drive diverse fusion processes. We also highlight common principles that can be derived from the analysis of the role of these proteins. [ABSTRACT FROM AUTHOR]

Circular dichroism and scanning probe microscopy were used to characterize the interaction of DNA with the nonhistone chromatin protein HMGB1 and its recombinant version HMGB1(A+B) devoid of the C-terminal acidic region. The AFM data corroborate the earlier suggestion concerning the action of tandem DNA-binding domains, and support a modulatory role of the C-terminal domain in HMG protein-DNA interactions. [ABSTRACT FROM AUTHOR]

Abstract  Two novel complexes, (AuCl)4L3(I) and (PdCl2)2L3(II) (L3 is calix[4]arene-thioether), were synthesized and their structures were determined. In complex I, one thioether group of molecule L3 is coordinated to every Au atom. In complex II, the bidentate coordination of L3 to the Pd atoms is observed; two thioether groups are in the trans-positions in the Pd square surrounding. Both complexes have the layered crystal lattices. In the Au complex, the layers are more stable due to the short contacts Au-Au (3.19–3.23 Å). [ABSTRACT FROM AUTHOR]

Abstract  Specific features of the behavior of the supramolecular metal complex catalysts based on calixarenes, cyclodextrins, and dendrimers in the reactions of hydroformylation, Wacker oxidation, hydroxylation of aromatics, 2-naphthol coupling, and oxidative coupling of styrenes and benzene were studied. The factors affecting the catalytic activity and selectivity are discussed. [ABSTRACT FROM AUTHOR]

Tetraarylresorcinarenes in a chair conformation of C2h symmetry were synthesized by sterically oriented condensation of aromatic aldehydes with resorcinol and 2-methylresorcinol. By further phosphorylation of resorcinarenes with phosphorous amides perphosphorylated derivatives were obtained with rctt configuration of substituents at internuclear methylidene bridges. Structure of these compounds was proved using NMR spectroscopy and X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Abstract  Monomeric and polymeric 1:2 complexes of a novel calix[4]arene-tetraphosphineoxide with Co(II) or Ni(II) nitrates were synthesized and analyzed by the X-ray method. In the monomeric complexes each metal cation is coordinated by two bidentate NO3-ligands as well as by two proximal P=O groups at the calixarene skeleton. In the nickel metallopolymer one sort of the cations is bound by the two proximal P=O-groups but other cations link neighboring calixarene molecules through Р=О���Ni���O=P chains. The complexes possess molecular cavities or channels filled by solvent molecules. [ABSTRACT FROM AUTHOR]

Abstract  Four new azocalix[4]arenes {5,11,17,23-tetrakis[(2-hydroxy-5-tert-butylphenylazo)]-25,26,27,28-tetrahydroxycalix[4]arene (1), 5,11,17,23-tetrakis[(2-hydroxy-5-nitro phenylazo)]-25,26,27,28-tetrahydroxycalix[4]arene (2), 5,11,17,23-tetrakis[(2-amino-5-carboxylphenylazo)]-25,26,27,28-tetrahydroxycalix[4]arene (3) and 5,11,17,23-tetrakis[(1-amino-2-hydroxy-4-sulfonicacidnapthylazo)]-25,26,27,28-tetrahydroxycalix[4]arene (4)} have been synthesized from p-tert-butylphenol, p-nitrophenol, p-aminobenzoic acid and 1-amino-2-hydroxy-4-sulphonic acid by diazo coupling reaction with p-aminocalix[4]arene. The resulting ligands (1–4) were treated with three transition metal salts (e.g., CuCl2�2H2O, NiCl2�6H2O or CoCl2�6H2O). Cu(II), Ni(II) and Co(II) complexes of the azocalix[4]arene derivatives were obtained and characterized by UV-vis, IR, 1H-NMR spectroscopic techniques and elemental analysis. All the complexes have a metal:ligand ratio of 2:1. The Cu(II) and Ni(II) complexes of azocalix[4]arenes are square-planar, while the Co(II) complexes of azocalix[4]arenes are octahedral with water molecules as axial ligands. The solvent extraction of various transition metal cations from the aqueous phase to the organic phase was carried out by using azocalix[4]arenes (1–4). It was found that, azocalix[4]arenes 1, 2 and 3 examined selectivity for transition metal cations such as Ag, Hg and Hg2. In addition, the thermal stability of metal:azocalix[4]arene complexes were also reported. [ABSTRACT FROM AUTHOR]

Abstract  New phosphorylated calix[4]resorcinarene and cavitands were synthesized. Their extraction ability toward LaIII, GdIII, and YbIII ions was studied. The cavitands are more efficient extracting agents than octasubstituted calix[4]resorcinarenes. The nature of substituents at the nitrogen atom at the upper rim and hydrophobic substituents at the lower rim exerts a substantial effect on the solubility of the extracted complex in chloroform. Coordination of two lanthanide ions with an extragent molecule results in their efficient but non-selective extraction. The literature and our spectral (31P NMR) data suggested that the ligand in the extracted complex has most probably a “kite” conformation. [ABSTRACT FROM AUTHOR]

The extractive properties of 5,11,17,23-tetra- tert-butyl-25,26,27,28-tetrakis(diphenylphosphinoylmethoxy)calix[4]arene towards thorium(IV) and europium(III) ions are studied. The conventional log-log analysis of the extraction data reveals that the stoichiometry of the extracted species is 1 : 1 metal ion to ligand ratio for the two metals. The effects of ligand concentration, types of diluent and concentration of the salting-out agents are investigated and discussed. The selectivity of the ligand for thorium and europium ions versus Mn2+, Pb2+, Cd2+, Fe2+, Ni2+ and Co2+ is examined. [ABSTRACT FROM AUTHOR]

We report a 16-year-old girl and her one-year-younger sister, both heterozygous for the c.34del24 mutation of the GLA (alpha-galactosidase A) gene, which they inherited from their father who is affected by Fabry disease (FD). Both girls presented with macrohematuria and rapidly progressing proteinuria. Urine analysis revealed glomerular hematuria and a nephrotic range of proteinuria suggesting a concomitant glomerulonephritis. Light microscopy of kidney biopsy was characteristic of IgA nephropathy (IgA deposits in mesangial areas and glomerular capillary loops, and mesangial hypercellularity), whereas electron microscopy showed changes typical of Fabry disease (multiple osmiophilic inclusions in the subendothelial and mesangial areas). These two cases and similar reports in the literature suggest that IgA nephropathy in FD is not merely coincidental. [ABSTRACT FROM AUTHOR]

Objective: To review histopathological and clinical data linking endocrine failure totraumatic brain injury (TBI) during acute neurosurgical treatment and rehabilitation.Methods: A focused search of the Medline (PubMed) medical literature database and theauthors'' files were used to identify selected publications.Results: Endocrine failure may produce clinically important consequences during acute andconvalescent care after TBI, and may be caused by direct injury to the hypothalamic-pituitary axis (HPA), neuroendocrinological effects from catecholamines and cytokines,or from systemic infection/inflammation that produces primary gland failure. Autopsyevidence of hemorrhage or ischemia in the HPA is common soon after TBI.The estimated incidence of acute hormone reduction is adrenal 15%, thyroid 5 - 15%,growth hormone 18%, vasopressin 3 - 37%, and gonadal (25 - 80%). Hyperprolactinemiaoccurs in more than 50% of patients. Inappropriate secretion of antidiuretic hormone(SIADH) and the euthyroid sick syndrome are common. Acute adrenal failure, centralhypothyroidism, SIADH, and diabetes insipidus (DI) may cause poor neurological outcomesincluding death, hypo/hypernatremia, hypotension, and increased vasoactive drugrequirements. Treatment of those conditions is warranted.Delayed diagnosis of hypopituitarism is often mistaken for symptoms of residual headinjury. Some chronic hormone deficiency occurs in 30 - 40% of selected patients after TBI,more than one deficiency in 10 - 15%, growth hormone in 15 - 20%, gonadal hormones in15%, and hypothyroidism in 10 - 30%. Chronic adrenal failure and DI are reported over awide incidence. Prolactin is elevated in 30%. All clinical symptoms respond favorably toreplacement therapy.Conclusions: Severe TBI associated with basilar skull fracture, hypothalamic edema,prolonged unres ponsiveness, hyponatremia, and/or hypotension is associated with ahigher occurrence of endocrinopathy. Greater awareness of this possible complication ofTBI and appropriate testing are encouraged. [ABSTRACT FROM AUTHOR]

Gene therapy is a new therapeutic approach for the treatment of human cancers. Gene expression systems that can be regulated by drugs have been developed to improve the safety and efficacy of therapeutic transgene delivery. One of the most promising systems is the tetracycline (Tet)-responsive system in the Tet-On configuration. A major problem of the Tet-On system if used in viral vectors is the high basal activity of the Tet response element (TRE) promoter leading to leaky expression of transgenes under uninduced conditions. We therefore evaluated novel TRE promoters for controlling gene expression in an adenovirus vector (AdV) Tet-On system and further investigated them for expression of the pro-apoptotic CD95/Fas ligand (FasL) in human epithelial carcinoma cell line (HeLa) and lung cancer cells. Plasmid-based reporter gene assays showed that modifications within the tetO 7 and minimal immediate early cytomegalovirus promoter (CMV)min sequence of the TRE promoter reduced its leakiness and led to a markedly improved regulatability by doxycycline. Among several TRE promoters tested, a new construct (TRE-Tight1) containing modifications of both the tetO 7 sequence and the CMVmin showed 11-fold reduced leakiness and 1.5-fold increased absolute transgene expression levels after induction, as compared to the original TRE. Under induced conditions, a TRE-Tight1 promoter-dependent AdV expressing the pro-apoptotic CD95L/FasL induced apoptosis and cell lysis in HeLa cells as efficiently as an AdV containing the original TRE promoter. In contrast to the latter, however, the vector with the modified TRE promoter left cells totally unaffected in the absence of the inducer. Stringently regulated induction of apoptosis and cell death by TRE-Tight1-AdV was also demonstrated in three human lung cancer cell lines. These data show that the novel TRE-Tight1 promoter has a high potential for closely controlled and efficient expression of cytotoxic genes in AdV-based anti-cancer approaches. [ABSTRACT FROM AUTHOR]

The leafhoppers, planthoppers and their allies (collectively known as the Auchenorrhyncha) are presented as a group of insects that are highly appropriate for studying grassland ecology and conservation, evaluating the conservation status of sites and monitoring environmental and habitat change. Semi-natural grasslands typically support dense populations and a wide range of species with diverse ecological strategies. Their numerical dominance in many grasslands means that they have considerable functional significance, both as herbivores and as prey for higher trophic levels. Population and assemblage studies are supported by good ecological knowledge about most species and modern identification keys. Hitherto, most studies have focused on the composition and structure of assemblages and how they are affected by conservation management. However, grasslands support many rare species with small and fragmented populations which deserve conservation attention in their own right, and recent work has started to reflect this. The effects of management on the composition and structure of grassland leafhopper populations and assemblages are described and an assessment is given of the main threats facing individual species and overall diversity. There is a need to synthesise the scattered literature on grassland leafhoppers, to provide a model for how the composition and structure of populations and assemblages respond to major environmental and anthropogenic gradients across large biogeographic areas. Such an analysis could help predict the impact of likely future changes in land use and climate. [ABSTRACT FROM AUTHOR]

Purpose: To clarify the association between disturbed thyroid hormone metabolism (lowT3 syndrome) and release of cytokines and markers of cell-mediated immune response. Material and Methods: Concentrations of cytokines as well as of thyroid hormones were determined in 32 patients suffering from severe traumatic brain injury: interleukin-(IL-)1, IL-6, IL-10, tumor necrosis factor, transforming growth factor-(TGF-)β, soluble interleukin-2 receptor (slL-2R), neopterin, and β2-microglobulin (β2m) in serum and cerebrospinal fluid; triiodothyronine (T3), free T3, thyroxine (T4), free T4, thyrotropin, thyroxine-binding globulin,and albumin in serum. Additionally, clinical parameters were assessed: Glasgow Coma Score, CT scan, intracranial pressure, Glasgow Outcome Score,and occurrence of pneumonia. Results: Among 31 patients with a low T3 syndrome, those with additional low serum T4 levels (n = 13) showed a prolonged suppression of serum β2m, neopterin, and slL-2R, and a higher secondary increase of serum β2m, neopterin,and TGF-β,as well as lower T3 levels (all p < 0.05).These patients also had a longer stay in the intensive care unit (34 ± 6 days vs. 22 ±12 days; p = 0.008). Increased levels of β2m correlated with a preceding decrease of thyrotropin (cerebrospinal fluid: r = -0.53; p = 0.004; serum: r = -0.41; p = 0.029). Associations of thyroid hormone metabolism with either other cytokines or with clinical parameters were not detected. Conclusion: These results show that low T3 syndrome is a very common pathophysiological feature after severe traumatic brain injury. The association of a low T3 syndrome in combination with low serum T4 levels, with an altered time course of markers of cell-mediated immunity led the authors to hypothesize that a disturbed thyroid hormone metabolism may be interrelated with a prolonged cellular immune dysfunction after traumatic brain injury. [ABSTRACT FROM AUTHOR]

Solvent extraction of tetravalent thorium and trivalent europium ions from nitrate media into dichloromethane solution of triphenylphosphine oxide (TPPO) has been studied. The extractant was shown to be more efficient for europium than for thorium. A conventional log-log analysis reveals that the extraction of both metal nitrates takes place via the formation of the species with 1 : 2 metal to ligand ratio. Thermodynamic parameters i.e., ΔG°, ΔH° and ΔS° of the extraction process using 1,2-dichloroethane as diluent have been calculated based on the influence of the temperature on extraction equilibria in the range 293-313 K. While the extraction of europium is controlled by enthalpy changes, the extraction of thorium is an endothermic process and is driven by entropy changes. A comparison of these data with those obtained for the extraction of europium and thorium nitrates by two other related phosphorylated ligands, tri-n-octylphosphine oxide (TOPO) and diphenyl-N,N-dimethylcarbamoylmethylphosphine oxide (DФDMCMPO), indicates that DФDMCMPO coordinates presumably as a chelating ligand. [ABSTRACT FROM AUTHOR]

Objective: To investigate the incidence and type of endocrine abnormalities in critical care patients with traumatic brain injury (TBI) and to examine their relationships to possible predisposing factors.Design: Prospective study.Setting: General intensive care unit in a university hospital.Patients and Participants: Thirty-four TBI patients (27 men, 7 women), having a mean age of 37+/-16 years, were studied after weaning from mechanical ventilation.Interventions: Baseline endocrine assessment was carried out by measuring cortisol, corticotropin, dehydroepiandrosterone sulfate, free thyroxine, thyrotropin (TSH), testosterone, oestradiol, follicle stimulating hormone (FSH), luteinizing hormone, prolactin, growth hormone and insulin-like growth factor I. Dynamic evaluation was performed by human corticotropin releasing hormone and growth hormone releasing hormone in all patients. Male patients underwent additional investigation with gonadotropin-releasing hormone. Severity of neurological derangement was graded according to Glasgow Coma Scale (GCS), Marshall Computerized Tomographic Classification and intracranial pressure (ICP) levels.Measurements and Results: Eighteen of the 34 patients (53%) had an abnormal result in at least one hormonal axis tested, with cortisol hyporesponsiveness and gonadal dysfunction being equally common, affecting 24% of patients. Endocrine abnormalities were associated with a higher brain CT-scan classification score ( p=0.02). The GCS on admission correlated positively with baseline FSH (r=0.37, p=0.03), peak FSH (r=0.41, p=0.03), testosterone (r=0.44, p=0.02) and TSH (r=0.39, p=0.03). There were no relations between ICP(max) and any baseline or dynamic hormone measurements.Conclusions: Patients with TBI receiving critical care show changes in their neuroendocrine responses, which depend upon clinical and radiological measures of head injury severity. Most common abnormalities include cortisol hyporesponsiveness and hypogonadism. [ABSTRACT FROM AUTHOR]

The influence of the concentration of dimethylaminomethylated calix[4]resorcinolarene I, pH, supporting electrolyte, and additions of 1, 10-phenanthroline to the organic phase on the distribution of Eu(III) and Am(TTT) between the aqueous and organic phases was studied. Compound I extracts Am and Eu ions from neutral aqueous solutions more efficiently when dissolved in 1-heptanol, compared to dichloroethane. Extraction is accompanied by formation of the third phase containing large amounts of the metals. As the concentrations of I and supporting electrolyte are increased, the Am/Eu separation factor grows, but in this case noticeable amounts of the metals appear in the third phase, which restricts the applicability of this system. Additions of 1,10-phenanthroline to the organic phase decrease by 2-3 orders of magnitude the concentration of I required for efficient extraction of Am and Eu, showing a synergistic effect. [ABSTRACT FROM AUTHOR]

Amide local anaesthetics used for regional anaesthesia in paediatric patients are potent sodium channel blockers with marked stereospecificity, which consistently influences their action, especially their toxic action on the heart. At toxic concentrations, they induce severe arrhythmias with the potential for cardiac arrest. These agents are all bound to serum proteins, mainly to α1-acid glycoprotein (AAG), but also to human serum albumin. Protein binding ranges from 65% (lidocaine) to more than 95% (bupivacaine, ropivacaine). Because AAG is a major acute phase protein, its concentration rapidly increases when inflammatory processes develop, particularly during the postoperative period. Neonates and infants have a lower AAG concentration in serum as compared with adults; therefore, their free fraction of local anaesthetics is increased accordingly. This has important clinical implications since, at least at steady state, the toxic effects of local anaesthetics are directly related to the free (unbound) drug concentration. After injection into the epidural space, absorption into the bloodstream follows a biphasic process. The buffering properties of the epidural space are important and prevent a rapid rise in concentration. In infants and children, the epidural space seems to protect patients in a similar manner. Moreover, it has been observed that the peak plasma concentration (Cmax) of ropivacaine is delayed in infants and children when compared with adults. The time to Cmax decreases from 90–120 minutes in infants aged less than 6 months to 30 minutes in children aged more than 8 years. This delay in Cmax may also be related to the lower clearance observed in younger patients. Local anaesthetics are metabolised by cytochrome P450 (CYP). The main CYP isoforms involved are CYP3A4 for lidocaine and bupivacaine and CYP1A2 for ropivacaine. CYP3A4 is not mature at birth but is partly replaced by CYP3A7. The intrinsic clearance of bupivacaine is only one-third of that in adults at 1 month of age, and two-thirds at 6 months. CYP1A2 is not fully mature before the age of 3 years. Indeed, the clearance of ropivacaine does not reach its maximum before the age of 5 years. However, at birth this clearance is not as low as expected, and ropivacaine may be used even in younger patients. [ABSTRACT FROM AUTHOR]

Larvae of Maculinea rebeli, one of the most endangered European butterflies, are obligatory social parasites of Myrmica ants. At present, this relationship is thought to be highly specific, with Myrmica schencki being regarded as the primary host. Here we present data on six populations from Poland and Austria, including the first record of Myrmica specioides as a host, together with published data from other central European countries, which severely questions the inference that M. schencki is the exclusive host of M. rebeli. Our results indicate that Myrmica sabuleti is the most frequently used host ant in central Europe, whereas M. scabrinodis, M. sulcinodis, M. specioides and M. schencki are used as secondary hosts. Possible explanations for this highly variable host use include (1) regional differences in semiochemicals, behaviour or social structure of the potential Myrmica host species and (2) the existence of different ecological subspecies or cryptic species of M. rebeli. Finally, we emphasize the importance of identifying local host ant species prior to further conservation strategies in order to avoid failure of management programs or even damage to populations on the edge of extinction. [ABSTRACT FROM AUTHOR]

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A series of calix[6]arenes substituted with phosphoryl functional groups were prepared by the Arbuzov reaction of hexakis(chloromethyl)calix[6]arene hexamethyl ether with isopropyl esters of trivalent phosphorus acids, followed by appropriate chemical transformations. Molecular modeling and NMR data show that phosphorylated calix[6]arenes exist in the stereochemically labile 1,2- alternate conformation. The extractive power of these compounds with respect to americium and europium was studied. Due to the cooperative binding of the metal cation with phosphoryl groups, the phosphorylated calixarenes are more effective extractants than their acylcic analogs and commercial organophosphorus extractants. [ABSTRACT FROM AUTHOR]

Despite the high prevalence of lumbosacral transitional vertebra (LSTV), little is known about the biomechanics of this condition. In addition, as previous studies have focused solely on symptomatic and elderly LSTV patients, the relationship between LSTV and congenital or developmental spinal stenosis remains uncertain. In the present study, the spinal canal diameters were measured in young subjects in whom degenerative changes have not yet become significant. Seventeen young adults with LSTV and 24 normal controls were included in this study. The spinal canal sagittal diameter, interpedicular distance, interfacet distance and lateral recess diameter were measured using CT scans. There was no significant difference in the measured values between the two groups. In conclusion, the results indicate that there is no relationship between LSTV and a congenitally narrower canal. [ABSTRACT FROM AUTHOR]

O,O-Dibutyl- N-benzylamino- and O,O-dibutyl- N-phenylaminomethylphosphonate derivatives of tetramethylcalix[4]resorcinolarenes were prepared and characterized. Their effectiveness in the extraction of lanthanum(III) ions from water to chloroform in the presence of picrate ions is demonstrated. This extraction is accompanied by the formation of a complex of the composition La(Pic)3(L)2. [ABSTRACT FROM AUTHOR]

Objectives: To assess the incidence of myocardial ischemia in meningococcus-induced purpura fulminans in pediatric patients, to compare troponin I (cTnI) levels with changes in electrocardiogram (ECG) and to evaluate whether cTnI is related to myocardial function and contractility, to severe acquired anticoagulant deficiency and to the severity of disease.Methods: Twenty-two patients with acute meningococcemia, supported with inotropes or vasoactive agents, were studied, Blood samples for the determination of serum cTnI and conventional myocardial ischemia and coagulopathy markers were drawn daily. Measurements of cardiac index (CI), ejection (EF) and shortening fractions (SF) and ECGs were performed daily.Results: The Leclerc score, the Neisseria sepsis index (NESI) and the pediatric risk of mortality (PRISM) score predicted a mean mortality rate of 34%, 27% and 23%, respectively. Four patients died (18%). Five patients (23 %) presented with myocardial ischemia. Their ECG ischemic changes were associated with pathologically high cTnI levels (1.93 +/- 0.13 vs 0.18 +/- 0.08 ng/ml, p < 0.001 for patients with or without ischemic changes) and depressed myocardial contractility (mean difference +/- SE -14 +/- 5%, p = 0.01, for the EF and -7.4 +/- 3, p < 0.02, for the SF). High cTnI values were significantly correlated to low protein C (PC) (p < 0.0001), factor VIII (p < 0.04) and antithrombin III (AIII, p = 0.01) levels, but not to the PRISM, Leclerc or the NESI scores. Means of AIII, VII, and especially of VIII, and PC, were significantly lower in ischemic than in non-ischemic patients, although severity scoring systems and inotropic support did not differ between the two groups. Survivors tended to significantly higher PC (p < 0.01) and factor VIII levels (p = 0.001) than non-survivors and, also, to lower levels of cTnI (p = 0.05) and CPK-MB (p < 0.05), while in meningococcal shock.Conclusions: The incidence of myocardial ischemia is increased in acute meningococcemia in pediatric patients and correlates with myocardial dysfunction. High cTnI is associated with severe coagulopathy, but not with clinical prognostic scores or inotropic support. Early recognition of myocardial injury, myocardial support and early replacement therapy with PC, AIII, factor VIII or fibrinogen might improve outcome in acute meningococcemia in children. [ABSTRACT FROM AUTHOR]

Discovered in the 1940’s, [1n]metacyclophanes with the common name calix[n]arenes which is derived from for the molecule’s shape enjoyed a remarkable interest in almost all fields of chemistry since the 1980’s, which is highlighted by several books [1–8]. Over 50 reviews concerning their synthesis, properties and applicabilities were published, many of those with emphasis on organic synthesis and structural properties are cited in ¶[P. 5–6 in 2]. Of interest for analytical chemists are reviews on calixarenes and the structurally related resorcin[n]arenes (or calix[n]resorcarenes) and calixpyrroles concerning potentiometric sensors [9–12], chromo- and fluorophores [13, 14], molecular switches [15], metal ion binding in solution [16–19], redox properties [20] and anion binding [21–24]. Other recent reviews deal with thermodynamic aspects [25], organometallic compounds [26], P-containing calixarenes [27–29], as well as molecular dynamics modeling [30–33]. It is a vital field with over 200 publications per year. Therefore, this article presents only selected results on complexation, solvent extraction and membrane transport with the emphasis on ion and molecular recognition which can be used for analytical purposes, without attempting to cover all available references. [ABSTRACT FROM AUTHOR]