ESR

Distribution by Scientific Domains
Distribution within Medical Sciences

Terms modified by ESR

  • esr measurement
  • esr signal
  • esr spectroscopy
  • esr spectrum
  • esr studies
  • esr study

  • Selected Abstracts


    Spin-lattice relaxation of spin-½ nuclei in solids containing diluted paramagnetic impurity centers.

    CONCEPTS IN MAGNETIC RESONANCE, Issue 1 2003

    Abstract Dynamic nuclear polarization of nuclear spins via the solid-state and thermal mixing effects is discussed. Continuous-wave S- and X-band microwave radiation have been employed to measure 13C signal enhancements and polarization times for 13C nuclei in a natural type Ib diamond as a function of magnetic field. It was found that thermal mixing plays an important role in the 13C signal enhancement because the central electron spin resonance (ESR) line width HL , H0,C/,e, resulting in flip-flip and flip-flop forbidden transitions taking place simultaneously. On the other hand, the 13C spin-lattice relaxation rate is determined to a large extent by the solid-state effect (forbidden transitions). 13C polarization rates have also been measured for a suite of natural diamonds. It is shown that the polarization rate is proportional to the paramagnetic impurity concentration, in agreement with the theory. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson 19A: 36,43, 2003. [source]


    Effect of NaCl filler on ferroelectric phase and polaron configurations of PVDF films

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 4 2007
    I. S. ElashmawiArticle first published online: 8 MAR 200
    Abstract Polyvinyldene fluoride (PVDF) films filled with NaCl of mass fraction range 1 , W , 6 % were prepared by casting technique. Their crystalline structure, thermal, optical properties and Electron spin resonance (ESR) were examined. X-ray diffraction (XRD) and differential thermal analysis (DTA) measurements indicated a maximum ferroelectric ,-phase increment at 4%. DTA was used to identify the phase transition temperatures, the order of reaction and the activation energy of melting. The UV-Visible optical absorption implied a minimum value of the estimated optical energy gap at W = 4%. ESR spectra contained a Lorentizian signal exhibiting a minimum value of the symmetry factor at W = 4%. The energy levels of the optical gap boundaries were though to contribute to ESR transitions. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Association of components of the metabolic syndrome with the appearance of aggregated red blood cells in the peripheral blood.

    DIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 2 2005
    An unfavorable hemorheological finding
    Abstract Background Components of the metabolic syndrome are associated with low-grade inflammation. This can be accompanied by the synthesis of sticky proteins and erythrocyte aggregation. Methods The degree of erythrocyte aggregation was evaluated by a simple slide test and image analysis along with other markers of the acute-phase response, including the white blood cell count (WBCC), erythrocyte sedimentation rate (ESR), fibrinogen and high sensitivity C-reactive protein (hs-CRP) concentrations. Patients were categorized in four groups according to the absence or presence of 1, 2 and 3 or more components of the metabolic syndrome. Results We examined a total of 1447 individuals (576 women and 871 men) who gave their informed consent for participation. A significant cardiovascular risk factors, age and hemoglobin adjusted correlation was noted between the degree of erythrocyte aggregation and the number of components of the metabolic syndrome (r = 0.17, p < 0.0005). This correlation was better than that observed for clottable fibrinogen (r = 0.13 p < 0.0005), for ESR (r = 0.11 p < 0.0005) or WBCC (r = 0.13 p < 0.0005). A somewhat better correlation was noted for hs-CRP (r = 0.26 p < 0.0005). Conclusions The multiplicity of components of the metabolic syndrome is associated with enhanced erythrocyte aggregation, probably related to the presence of multiple adhesive macromolecules in the peripheral blood. The enhanced aggregation might contribute to capillary slow flow, tissue deoxygenation as well as vasomotor tone changes in the presence of multiple components of this syndrome. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    Potential role of soluble angiopoietin-2 and Tie-2 in patients with inflammatory bowel disease

    EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 2 2006
    I. E. Koutroubakis
    Abstract Background, Angiogenesis has been suggested to play an important role in inflammatory bowel disease (IBD). The aim of the study was to evaluate the serum markers of angiogenesis angiopoietin-2 (Ang-2) and soluble angiopoietin receptor Tie-2 in patients with ulcerative colitis (UC) and Crohn's disease (CD). Materials and methods, Serum Ang-2 and Tie-2 serum levels were measured in 160 IBD patients (79 UC and 81 CD) and in 80 matched healthy controls using commercially available enzyme-linked immunosorbent assays. Serum Ang-2 and Tie-2 levels were correlated with the disease activity, as well as the type, localization and treatment of the disease. Results, Median serum Ang-2 and Tie-2 levels were significantly higher in both the UC patients and the CD patients compared with the healthy controls (P < 0·05 and P < 0·001, respectively). The IBD patients with early disease (diagnosis < 2 years) had significantly higher (P = 0·04) median serum Ang-2 levels but significantly lower (P = 0·02) median serum Tie-2 levels as compared with IBD patients with late disease (diagnosis > 2 years). The CD patients with active disease had significantly higher levels of Ang-2 compared with non-active disease (P = 0·02). Serum levels of both Ang-2 and Tie-2 were not correlated with laboratory markers such as ESR, CRP, white blood cell count, platelet count and albumin. Conclusions, Serum Ang-2 and Tie-2 levels are elevated in patients with IBD. These markers may mediate angiogenesis and vascular permeability in the mucosa of patients with IBD. [source]


    HEPATITIS C AND ADDICTION: Chronic viral hepatitis is a significant contributor to the immunosenescent phenotype of parenteral drug addiction

    ADDICTION BIOLOGY, Issue 2 2009
    Albert S. Reece
    ABSTRACT Intravenous drug addiction is known to be associated with an inordinate morbidity and mortality. As our previous report had identified an immune phenotype consistent with accelerated ageing, we wished to investigate how much of this change may have been related to chronic viral hepatitis. A total of 12 409 clinical pathology results from the period 1995,2007 were reviewed. To control for the differences in age, only patients less than 48 years of age were considered. A total of 636 substance use disorder (SUD) and 6103 non-SUD (N-SUD) patients were studied. They had comparable ages (mean ± SD 31.32 ± 6.90 versus 31.57 ± 9.23, P -value not significant), but the SUD group had more males (74.37% versus 53.20%, P < 0.001). For most of the changes examined splitting the two SUD groups into hepatitis C positive (HCV+) and hepatitis C negative (HCV,) demonstrated that the majority of the described changes were most marked in the HCV+ group. The globulins were higher in the HCV+ group and the albumin was lower and fell more markedly with age than in N-SUD or HCV, (all P < 0.001). The globulin/albumin ratio was significantly higher in HCV+ than HCV, or N-SUD (both P < 0.0001) and rose more with age. These changes were paralleled by the ESR, elevations in the CRP and lymphocyte count. Transaminases were elevated in SUD and HCV+ groups compared with N-SUD (all P < 0.02). At multivariate analysis ESR, lymphocyte count, dual hepatitis B and C seropositivity, AST and HCVAb were significant predictors of the serum globulin level and accounted for 21% of the variance. These data extend our earlier report and show that much of the immunosenescent phenotype of SUD, encompassing the known immunosuppression and the observed immunostimulation, is statistically related to chronic viral hepatitis. Important theoretical and practical management (vaccination) implications ensue. [source]


    Study on the Photochromism of Ni,Al Layered Double Hydroxides Containing Nitrate Anions

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 14 2006
    Min Wei
    Abstract The photochromism of nitrate-containing nickel,aluminum layered double hydroxides (NiAl-NO3 -LDHs) has been studied. Powder X-ray diffraction (PXRD), FTIR, UV/Vis, XPS, ESR, EXAFS, and elemental analysis were used to investigate the structure, composition, and photochromic behavior of NiAl-NO3 -LDHs. A possible photochromic mechanism in NiAl-NO3 -LDHs has been proposed.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source]


    XAS, ESR and Potentiometric Studies of Three Dinuclear N,N, -para -Xylylenebis(tetraazamacrocycle)copper(II) Complexes , X-ray Crystal Structure of [N,N,- p -Xylylenebis(cyclen)]copper(II)

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2003
    Mathieu Soibinet
    Abstract Dicopper complexes with N,N, - p -xylylenebis(cyclam or cyclen) and with the heteroditopic N,N, - p -xylylenebis(cyclam-cyclen) were synthesized. An X-ray study of the N,N, - p -xylylenebis(cyclen)dicopper complex showed that the copper(II) ion is five-coordinate with an H2O molecule in apical position. With this ligand, a polymeric chain was also obtained in the presence of KSCN. The terminal donor atoms of the bridging NCS, anion are coordinated in apical position to the square-pyramidal copper(II) ion. Two alternating kinds of Cu2L4+ moieties are present in the chain, the first with two N4S chromophores and the second with two N5 chromophores. EXAFS and XANES results are in agreement with a five-coordinate copper ion in the cyclen unit and a six-coordinate copper ion in the cyclam unit. Thermodynamic constants were determined by potentiometry. The existence of dinuclear Cu2L4+ species (ligand/metal ratio < 1) and mononuclear CuLHn(2+n)+ species (ligand/metal ratio > 1) were confirmed by an ESR study at variable pH. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source]


    Radical Cation and Dication Derived from 4,8-Diethylbenzo[1,2- d:4,5- d,]bis[1,2,3]trithiole [DEBBT]: Change of Electronic State from Singlet-State Dication DEBBT(2+)- S to Triplet-State Dimer 2DEBBT(2+)- T in D2SO4 and CD3CN Solutions

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2003
    Takeshi Kimura
    Abstract 4,8-Diethylbenzo[1,2- d:4,5- d,]bis[1,2,3]trithiole [DEBBT] was oxidized using concentrated D2SO4, leading to the generation of the radical cation DEBBT(·+) which was verified by ESR spectroscopy. DEBBT(·+) in the solution was further oxidized to produce the dication DEBBT(2+), as determined by 1H and 13C NMR spectroscopy. DEBBT(2+) was also prepared by treating DEBBT 1-oxide [DEBBT 1-O] with concentrated D2SO4, and was verified by 1H and 13C NMR spectroscopy. The 13C NMR chemical shifts of DEBBT(2+), calculated by the density functional theoretical (DFT) method at the B3LYP6-31G** level, correlated well with those obtained experimentally. The ESR signal of DEBBT(2+) generated from DEBBT 1-O was observed in solution, which implies that the singlet-state dication DEBBT(2+)- S isomerizes to the triplet-state dication DEBBT(2+)- T, and that two molecules of DEBBT(2+)- T further form a spin pair at one trithiole ring with significant distance between the two radical centers. The oxidation of DEBBT with one or two equivalents of single-electron oxidizing reagents produced DEBBT(·+) and DEBBT(2+), and the salts were isolated in a stable form. However, the DEBBT(2+) that was prepared by oxidation with NOPF6 proved silent for NMR in CD3CN, while ESR was active. The stability, electronic state, and NMR and ESR spectroscopy of the dication are affected by solvation with D2SO4 and CD3CN. The optimized structures and the total energy of the singlet- and triplet-state dication were calculated using the DFT method at the B3LYP6-31G** level, which shows that the structures of the singlet- and triplet-state dications have a completely planar form with 1.7 kcal/mol as the total energy difference between them. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source]


    The tripartite ATP-independent periplasmic (TRAP) transporters of bacteria and archaea

    FEMS MICROBIOLOGY REVIEWS, Issue 4 2001
    David J Kelly
    Abstract Until recently, extracytoplasmic solute receptor (ESR)-dependent uptake systems were invariably found to possess a conserved ATP-binding protein (the ATP-binding cassette protein or ABC protein), which couples ATP hydrolysis to the translocation of the solute across the cytoplasmic membrane. While it is clear that this class of ABC transporter is ubiquitous in prokaryotes, it is now firmly established that other, unrelated types of membrane transport systems exist which also have ESR components. These systems have been designated tripartite ATP-independent periplasmic (TRAP) transporters, and they form a distinct class of ESR-dependent secondary transporters where the driving force for solute accumulation is an electrochemical ion gradient and not ATP hydrolysis. Currently, the most well characterised TRAP transporter at the functional and molecular level is the high-affinity C4-dicarboxylate transport (Dct) system from Rhodobacter capsulatus. This consists of three proteins; an ESR (DctP) and small (DctQ) and large (DctM) integral membrane proteins. The characteristics of this system are discussed in detail. Homologues of the R. capsulatus DctPQM proteins are present in a diverse range of prokaryotes, both bacteria and archaea, but not in eukaryotes. The deduced structures and possible functions of these homologous systems are described. In addition to the DctP family, other types of ESRs can be associated with TRAP transporters. A conserved family of immunogenic extracytoplasmic proteins is shown to be invariably associated with TRAP systems that contain a large DctQM fusion protein. All of the currently known archaeal systems are of this type. It is concluded that TRAP transporters are a widespread and ancient type of solute uptake system that transport a potentially diverse range of solutes and most likely evolved by the addition of auxiliary proteins to a single secondary transporter. [source]


    ESR isochron dating analyses at Bau de l'Aubesier, Provence, France: Clues to U uptake in fossil teeth

    GEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 7 2001
    Bonnie A.B. Blackwell
    At Bau de l'Aubesier, Provence, Mousterian artifacts and human teeth occur in inhomogeneous ("lumpy") sedimentary deposits that include bone and tooth fragments and extensive burnt horizons. Electron spin resonance (ESR) isochron analyses of mammal teeth, which use multiple subsamples with different U concentrations, can measure the external dose rate experienced by the tooth regardless of reworking and sedimentary dose rate changes. Isochron analyses do depend on the U uptake model assumed, but can also identify teeth that have experienced secondary U uptake or leaching. Using 11 teeth from six archaeological layers, the isochrons demonstrate that at least three teeth have experienced secondary uptake. For eight teeth, the U uptake has apparently not followed strictly early (EU), linear (LU), or recent uptake (RU), but more closely approximates LU-RU. Comparing volumetrically averaged sedimentary geochemistry with thermoluminescent dosimetry suggests that fossil tissues in the sediment have also experienced LU-RU uptake. LU-RU uptake can explain standard ESR ages that underestimate the true fossil age. © 2001 John Wiley & Sons, Inc. [source]


    Dating methods for sediments of caves and rockshelters with examples from the Mediterranean Region

    GEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 4 2001
    H. P. Schwarcz
    A wide range of potential dating methods may be applied to archaeological deposits found in caves and rockshelters, depending on the nature of the deposit and age range of the deposit. Organic sediments, including faunal and floral material, can be dated by radiocarbon (AMS and high-sensitivity beta-counting). Many karstic features contain speleothems which can be dated with high accuracy by U-series. Wind-blown detritus, where it is the dominant constituent of the cave deposits, can be dated by luminescence (TL, OSL, or IRSL), taking care to avoid material fallen into the deposits from the shelter/cave walls. Fireplaces contain burned rocks (including stone artifacts) which can be dated by TL. Enamel from the teeth of mammals is present in most sites, representing either animal residents of the shelter, or residues from food brought to the shelter by human residents. Electron spin resonance (ESR) dating of enamel is applicable over a wide time range, with high accuracy and reasonable precision where uranium accumulation in teeth is low, but with lower precision where uranium content in teeth is high. In general, multiple dating methods applied to a site may resolve ambiguities arising from uncertain model assumptions in some dating methods. © 2001 John Wiley & Sons, Inc. [source]


    Detection of diluted marine tertiary tephra by electron spin resonance and magnetic measurements

    GEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2003
    B. Ananou
    SUMMARY Oligocene sediments from ODP leg 115 (South Indian Ocean), Site 709 and Site 711, have been investigated using electron spin resonance (ESR) and magnetic susceptibility measurements, to detect volcanic tephra layers of supposed Ethiopian traps origin. The results obtained at room temperature, without separating the volcanic material from the bulk sediment, show that the ash-content strongly influences the lineshape and intensity of the ESR signal. As a result, the ESR alone, can be used as a powerful tool for characterizing the diluted ash-content of marine sediments. We have also found a strong similarity between the ESR spectra of the same tephra layers from the two sites. [source]


    Rich Phase Behavior in a Supramolecular Conducting Material Derived from an Organogelator

    ADVANCED FUNCTIONAL MATERIALS, Issue 6 2009
    Josep Puigmartí-Luis
    Abstract Organic conducting fiber-like materials hold great promise for the development of nanowires that can act as connections in miniature electronic devices, as an alternative to inorganic nanometer scale structures. This article presents a conducting organic tetrathiafulvalene-based supramolecular material which possesses a rich phase behavior with different packing of the molecules in the different forms, evidenced by electron spin resonance (ESR) spectroscopy. The distinct phases of conducting nanofibers can be easily fabricated through the temperature control of their preparation process from a xerogel by doping with iodine vapors. A total of four conducting phases have been identified conclusively using ESR spectroscopy as the key analytical tool. Three of the phases show a good long-term stability and areas in which the I,V curves have ohmic behavior when studied by current sensing (conducting) AFM. They offer promise for applications where electrical nanometer scale connections are required. [source]


    Sumatriptan Scavenges Superoxide, Hydroxyl, and Nitric Oxide Radicals: In Vitro Electron Spin Resonance Study

    HEADACHE, Issue 9 2002
    DMSc, Yukio Ikeda MD
    Background.,The molecular mechanisms of migraine have not yet been clarified. Oxygen free radicals have been implicated in the genesis of many pathological processes, including migraine. Sumatriptan succinate is known to be a very effective drug for acute relief of migraine attack. Objective.,To investigate the direct scavenging activities of sumatriptan for superoxide, hydroxyl, and nitric oxide (NO) radicals using electron spin resonance (ESR) spectroscopy. Methods.,Measurement of superoxide and hydroxyl radical scavenging activities was performed by ESR using 5,5-dimethyl-1-pyrroline- N -oxide as a spin trap. NO was generated from 1-hydroxy-2-oxo-3-(N -3-methyl-3-aminopropyl)-3-methyl-1-triazene and analyzed by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl produced from the reaction between 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide and NO. Results.,The ESR study demonstrated that sumatriptan scavenged superoxide, hydroxyl, and NO in a dose-dependent manner. Conclusion.,Sumatriptan has direct scavenging activity on free radicals and NO. Acute migraine drugs with antioxidant properties may provide heretofore unheralded benefits via this mechanism. [source]


    Cover Picture: Spectroscopic and Photophysical Properties of a Highly Derivatized C60 Fullerol (Adv. Funct.

    ADVANCED FUNCTIONAL MATERIALS, Issue 1 2006
    Mater.
    Abstract The photo-oxidative stress in aqueous milieus can readily be generated in the presence of newly synthesized highly derivatized fullerenes (fullerols) reported in the Full Paper by Vileno and co-workers on p.,120. Their basic structural and photophysical properties were characterized using a range of methods, including X-ray photoelectron and IR spectroscopies, and electron spin resonance. Moreover, a significant drop of the local stiffness of a living cell was monitored using atomic force microscopy. This cell softening was attributed to the early effects of the photo-oxidative stress. Hydroxylated C60 molecules, also called fullerols, are a class of water-soluble fullerenes. Here we report the synthesis in acidic conditions of a highly derivatized fullerol (up to 36 carbons per C60 are oxidized). Spectroscopic investigations (X-ray photoelectron spectroscopy and infrared absorption) highlight the coexistence of both acidic and basic forms for the hydroxyl addends of derivatized C60. pH titrimetry reveals that, at millimolar concentrations, only ten protons per fullerol molecule are labile. Such a low value, as compared to 36 hydroxyl groups, is explained by the formation of clusters. A UV-vis absorption study performed over a large range of concentrations also points to the aggregation phenomenon. Moreover, this study shows that the clusters of fullerols appear at relatively low (micromolar) concentrations. An electron spin resonance (ESR) study, based on the attack of singlet oxygen (1,g) on 2,2,6,6-tetramethyl-4-piperidinol (TMP-OH), has proved the potential of hydroxylated C60 for performing efficient generation of singlet oxygen in aqueous solution. ESR measurements, which allow detection and quantification of 1,g, have also revealed the generation of reactive oxygen species (ROS). The yield of generation of 1,g and ROS is strongly correlated to the concentration of fullerol, thus also pointing to the aggregation of fullerol molecules. Exposing glioblastoma cells to oxidative stress in the presence of hydroxylated C60 and visible light has also been performed. Atomic force microscopy is used to monitor the relevant diminishment of the Young's modulus values for cells exposed to the oxidative stress. These results point to a possible application field of fullerols for performing bio-oxidations. [source]


    Defect-Related Optical Behavior in Surface Modified TiO2 Nanostructures

    ADVANCED FUNCTIONAL MATERIALS, Issue 1 2005
    M. Prokes
    Abstract The surface modification of TiO2 nanostructures to incorporate nitrogen and form visible light absorbing titanium oxynitride centers is studied. Anatase TiO2 structures in the 5,20,nm range, formed by a wet chemical technique, were surface modified and the nitridation of the highly reactive TiO2 nanocolloid surface, as determined by X-ray photoelectron spectroscopy (XPS) studies, is achieved by a quick and simple treatment in alkyl ammonium compounds. The nitriding process was also simultaneously accompanied by metal seeding resulting in a metal coating layer on the TiO2 structures. The structure of the resultant titanium oxynitride nanostructures remains anatase. These freshly prepared samples exhibited a strong emission near 560,nm (2.21,eV), which red-shifted to 660,nm (1.88,eV) and dropped in intensity with aging in the atmosphere. This behavior was also evident in some of the combined nitrogen doped and metal seeded TiO2 nanocolloids. Electron spin resonance (ESR) performed on these samples identified a resonance at g,=,2.0035, which increased significantly with nitridation. The resonance is attributed to an oxygen hole center created near the surface of the nanocolloid, which correlates well with the observed optical activity. [source]


    Generation and structure determination of 5,6-bis(methylthio)-4,7-diethylbenzo[1,2,3]trithiole dication MBT(2+)

    HETEROATOM CHEMISTRY, Issue 2 2005
    Takeshi Kimura
    5,6-Bis(methylthio)-4,7-diethylbenzo-[1,2,3]-trithiole [MBT] was oxidized with two equivalents of SbCl5 to produce a dication, MBT(2+),2SbCl, as a stable, dark-brown solid. MBT(2+) was unexpectedly silent for 1H-NMR in CD3CN, whereas it was active for ESR, suggesting that MBT(2+) is a triplet-state dication MBT(2+)-T. Meanwhile, treatment of 5- methylsulfinyl-6-methylthio-4,7-diethylbenzo[1,2,3]- trithiole [MBTMO] with D2SO4 produced MBT(2+), whose 1H-NMR gave no signals, whereas the solution is active for ESR. These results imply that MBT(2+) prepared from MBTMO is a triplet-state dication, and a singlet-state dication, MBT(2+)- S, initially generated by acidification of MBTMO, isomerized to the triplet-state dication, MBT(2+)- T. Since MBT(2+)- T is active for ESR at room temperature, two molecules of MBT(2+)- T should form a spin pair in the solution with a sufficient distance between the two radical centers. The structures of MBT(2+)- S and MBT(2+)- T were optimized with the DFT method at the B3LYP6-31G** level. The total energy difference between them was calculated to be 7.90 kcal/mol; MBT(2+)- T was shown to be more stable than MBT(2+)- S. A treatment of MBTMO with SbCl5 gave a 1:1 complex. The structure of the complex was determined with X-ray crystallography, which showed that the complex is the corresponding sulfonium salt, MBTMO,SbCl5. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:111,222, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20078 [source]


    Probiotic preparation VSL#3 induces remission in children with mild to moderate acute ulcerative colitis: A pilot study

    INFLAMMATORY BOWEL DISEASES, Issue 5 2009
    Hien Q. Huynh MD
    Abstract Background: Ulcerative colitis (UC) is a form of inflammatory bowel disease (IBD) that has periods of exacerbated symptoms and periods that are symptom-free. The treatment of active UC with probiotic bacteria could possibly induce remission. We evaluated the clinical efficacy and safety profile of probiotic preparation VSL#3 in the treatment of mild to moderate acute UC in the pediatric population. Methods: Eighteen eligible patients between the ages of 3,17 with mild to moderate acute UC received open-label VSL#3 daily in 2 divided doses for 8 weeks. The disease activity pre- and post-VSL#3 therapy was assessed by the simple clinical colitis activity index (SCCAI); Mayo ulcerative colitis endoscopic score; inflammatory markers: erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP); serum cytokine profiling; and rectal tissue microbial profiling done at baseline and at week 8. Results: Thirteen patients completed 8 weeks of VSL#3 treatment and 5 patients were withdrawn due to lack of improvement. Remission (defined as SCCAI ,3) was achieved in 56% of children (n = 10); response (decrease in SCCAI ,2, but final score ,5) in 6% (n = 1); and no change or worsening in 39% (n = 7). Post-VSL#3 treatments demonstrated a bacterial taxonomy change in rectal biopsy. The VSL#3 was well tolerated in clinical trials and no biochemical and clinical adverse effects attributed to VSL#3 were identified. Conclusions: Treatment of pediatric patients diagnosed with mild to moderate UC with VSL#3 resulted in a remission rate of 56% and a combined remission/response rate of 61%. (Inflamm Bowel Dis 2008) [source]


    Efficacy of infliximab in pediatric Crohn's disease: A randomized multicenter open-label trial comparing scheduled to on demand maintenance therapy

    INFLAMMATORY BOWEL DISEASES, Issue 3 2009
    Frank M. Ruemmele MD
    Abstract Background: Infliximab (IFX) is efficacious in inducing remission in severe forms of pediatric Crohn's disease (CD). Adult studies indicate that IFX is also safe and well tolerated as maintenance therapy. The present study aimed to evaluate in a prospective manner the efficacy and safety of IFX as maintenance therapy of severe pediatric CD comparing scheduled and "on demand" treatment strategies. Methods: Forty children with CD (nonpenetrating, nonstricturing as well as penetrating forms, mean age: 13.9 ± 2.2 years) with a severe flare-up (Harvey,Bradshaw Index [HBI] ,5, erythrocyte sedimentation rate [ESR] >20 mm/h) despite well-conducted immunomodulator therapy (n = 36 azathioprine, n = 1 mercaptopurine, n = 3 methotrexate) combined with steroids were included in this randomized, multicenter, open-label study. Three IFX infusions (5 mg/kg) were administered at week (W)0/W2/W6. At W10, clinical remission (HBI <5) and steroid withdrawal were analyzed and IFX responders were randomized to maintenance therapy over 1 year: group A, scheduled every 2 months; group B, "on demand" on relapse. Results: In all, 34/40 children came into remission during IFX induction therapy (HBI: 6.7 ± 2.5 (WO) vs. 1.1 ± 1.5 (W10); P < 0.001). At the end of phase 2, 15/18 (83%) patients were in remission in group A compared to 8/13 (61%) children in group B (P < 0.01), with a mean HBI of 0.5 versus 3.2 points (group A versus B, P = 0.011). In group A, 3/13 (23.1%) children experienced a relapse compared to 11/12 (92%) children in group B. No severe adverse event occurred during this trial. Conclusions: IFX is well tolerated and safe as maintenance therapy for pediatric CD, with a clear advantage when used on a scheduled 2-month basis compared to an "on demand" basis. (Inflamm Bowel Dis 2009) [source]


    Enhanced formation of advanced oxidation protein products in IBD

    INFLAMMATORY BOWEL DISEASES, Issue 6 2008
    Malgorzata Krzystek-Korpacka PhD
    Abstract Background: Advanced oxidation protein products (AOPPs) are new protein markers of oxidative stress with pro-inflammatory properties, accumulated in many pathological conditions. The issue of their enhanced formation in IBD has not been addressed yet. Methods: The concentration of relative AOPPs (rAOPP; concentration of AOPPs divided by albumin level) were measured in 68 subjects with ulcerative colitis (UC), 50 subjects with Crohn's disease (CD) and 45 healthy volunteers, and related to disease phenotype, clinical and biochemical activity, and therapeutic strategy. Diagnostic utility of rAOPP was evaluated by ROC analysis. Results: In comparison with controls (1.367 ,mol/g), rAOPP were increased in inactive (1.778 ,mol/g, P = 0.053) and active (1.895 ,mol/g, P = 0.013) UC and in active (1.847 ,mol/g, P = 0.003) CD. In CD, but not UC, rAOPP correlated with disease activity (r = 0.42, P = 0.013). Significant correlations with the inflammatory/malnutrition indices-erythrocyte sedimentation rate (ESR) (r = 0.53), leukocytes (r = 0.33), platelets (r = 0.38), IL-6 (r = 0.36), and transferrin (r = ,0.35) were demonstrated in CD. In UC, rAOPP correlated only with ESR (r = 0.35) and IL-6 (r = 0.30). Instead, associations with antioxidant dismutase (r = 0.29) and catalase (r = 0.22) were observed. The diagnostic power of rAOPP in discriminating diseased from non-diseased subjects was less than that of C-reactive protein (CRP). Simultaneous determination of rAOPP and CRP did not significantly improve the power of single CRP determination. Conclusions: IBD was associated with enhanced formation of AOPP, which differed between C and UC with respect to the relationship between rAOPP and disease activity, inflammatory and antioxidant response. These differences may reflect divergent ways that oxidative stress develops in CD and UC. The diagnostic power of rAOPP was insufficient for its clinical application. (Inflamm Bowel Dis 2008) [source]


    Fecal S100A12 and fecal calprotectin as noninvasive markers for inflammatory bowel disease in children

    INFLAMMATORY BOWEL DISEASES, Issue 3 2008
    Marc A. Sidler MD
    Abstract Background: Fecal calprotectin is a sensitive marker for gut inflammation. Recently, we have established that a related protein, S100A12, is elevated in the feces of children with inflammatory bowel disease (IBD). This may represent a specific and sensitive disease marker. The objective was to investigate the utility of fecal S100A12, in comparison to fecal calprotectin and standard inflammatory markers, as a screening marker for IBD in children with gastrointestinal symptoms. Methods: Stool samples were obtained from 61 children presenting with gastrointestinal symptoms requiring endoscopy. Fecal S100A12, calprotectin, and serum S100A12 levels were measured and correlated to final diagnosis and standard tests (ESR, CRP, platelet count, and albumin). Results: Children diagnosed with IBD (n = 31) had elevated fecal S100A12 (median 55.2 mg/kg) and calprotectin (median 1265 mg/kg) levels compared with the children without IBD (n = 30; S100A12: median 1.1 mg/kg, P < 0.0001; calprotectin: median 30.5 mg/kg; P < 0.0001). The sensitivity and specificity of fecal S100A12 (cutoff 10 mg/kg) for the detection of IBD were both 97%, whereas fecal calprotectin (cutoff 50 mg/kg) gave a sensitivity of 100% and a specificity of 67%. Conclusions: Both fecal markers were superior to the sensitivities and specificities of any standard inflammatory test. Both fecal S100A12 and calprotectin are sensitive markers of gastrointestinal inflammation, but fecal S100A12 provided exceptional specificity in distinguishing children with IBD from children without IBD. Fecal S100A12 is a simple, noninvasive test that can be used to screen and select children warranting further invasive and laborious procedures such as endoscopy for the investigation of their gastrointestinal symptoms. (Inflamm Bowel Dis 2007) [source]


    Local and systemic interleukin-18 and interleukin-18-binding protein in children with inflammatory bowel disease

    INFLAMMATORY BOWEL DISEASES, Issue 1 2008
    Steven T. Leach
    Abstract Background: Interleukin-18 (IL-18) is increased in the inflamed mucosa of patients with Crohn's disease (CD). The balance between this pleiotropic proinflammatory cytokine and its natural inhibitor, IL-18-binding protein (IL-18BP), may contribute to the pathogenesis of inflammatory bowel disease (IBD). Methods: Serum and mucosal biopsies were collected from children with IBD, from children with celiac disease, and from controls. Biopsies were maintained in culture for 24 hours, and supernatant was collected. Serum and supernatant IL-18 and IL-18BPa concentrations were measured by immunoassay. Disease activity score (PCDAI) and standard serum inflammatory markers (albumin, platelets, ESR, and CRP) were recorded. Results: Serum IL-18 was greater in children with CD (537 pg/mL) than in controls (335 pg/mL; P < 0.05) but not in children with ulcerative colitis (UC) or IBD type unclassified (IBDU). Mucosal IL-18 was greater in children with CD and UC/IBDU than in controls (P < 0.01). Serum IL-18BPa was increased in children with CD compared with that in controls (3.9 versus 2.6 ng/mL; P < 0.05), but was not elevated in children with UC/IBDU. Furthermore, calculated free-serum IL-18 was elevated in CD, but not UC/IBDU, compared with that in controls (P = 0.001). Total and free-serum IL-18 were elevated in severe CD relative to in mild/moderate disease. Conclusions: IL-18, produced in the colons of children with IBD, may contribute to local inflammatory changes. Systemic IL-18 level may be a useful indicator of gut inflammation. Furthermore, free IL-18 is greatly elevated in children with CD, suggesting that compensatory increases in IL-18BPa are insufficient. Further exploration of the role of this cytokine in the pathogenesis of IBD is now required. (Inflamm Bowel Dis 2007) [source]


    Steroid responsiveness in a case of Riedel's thyroiditis and retroperitoneal fibrosis

    INTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 3 2004
    P.K. Moulik
    Summary Riedel's thyroiditis is a rare chronic inflammatory disease of the thyroid characterised by an invasive fibrotic process. We present a lady with newly diagnosed hypothyroidism, rapidly enlarging hard, fixed goitre, strongly positive thyroid antibodies and raised erythrocyte sedimentation rate (ESR). A tru-cut biopsy confirmed Riedel's struma. Regression of the goitre and reduction of antibody titres occurred after starting prednisolone, which was stopped after 10 months. Six months later, she presented with renal failure due to retroperitoneal fibrosis that was successfully treated by reinstitution of steroids and ureteric stenting. Very high titres of thyroid antibodies and hypothyroidism predating development of goitre suggest coexistence of Hashimoto's thyroiditis and Riedel's thyroiditis. Tru-cut biopsy obviated the need for open thyroidectomy. A predominantly inflammatory as opposed to fibrotic thyroid histology may predict good response to steroids. Relapse following steroid withdrawal may not only be in the thyroid but also at other sites. [source]


    Formation of Lipid Emulsions and Clear Gels by Liquid Crystal Emulsification

    INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2007
    T. Suzuki
    Recently developed emulsion technologies for the formation of fine emulsions, lipid emulsions and clear gels by liquid crystal emulsification were reviewed. As a basic information on liquid crystal emulsification, the structures and characteristic behaviours of lyotropic liquid crystals were summarized. Formation of a liquid crystalline phase was often seen in emulsions and biological systems. The significance of liquid crystal formation during emulsification was analysed by comparing the states and stabilities of emulsions prepared by different processes. Then uses of liquid crystals for formation of the characteristic emulsions and gels were also discussed. In liquid crystal emulsification, an oil phase is dispersed directly into the lamellar liquid-crystalline phase composed of surfactant, glycerol and water to prepare a gel-like oil-in-liquid crystal emulsion. This is followed by dilution with the remaining water to produce an emulsion. From the phase behaviour during emulsification and analysis of the local motion of the liquid crystal membrane by fluorometry, it was confirmed that the interaction between surfactant and a polyol molecule such as glycerol promotes hydrogen bonding and enhances the strength of the lamellar liquid crystal membranes, which results in the formation of oil-in-liquid crystal emulsions. The interaction between the liquid crystal and oil was analysed from the changes in molecular motion of the membrane at the oil-liquid crystal interface using the spin label technique of electron spin resonance (ESR). The fluidity of the liquid crystal membrane did not change when oil was added, and therefore oil-in-liquid crystal emulsions of various oils were prepared by the identical process. This lack of dependence of the liquid crystal membrane on oil results in the unique properties of liquid crystal emulsification, which can be used for oils of various polarity and different molecular constituents. When a self-organizing artificial stratum corneum lipid containing pseudo-ceramide was used as a principal component of the oil, a multilamellar emulsion of concentric lamellar structure was formed. The multilamellar emulsion supplements the physiological function of stratum corneum by the identical mechanism as natural intercellular lipids. High-pressure treatment of the lipid emulsion produced a gel-like emulsion crystal, in which the homogeneous nanoemulsion droplets were arranged in a hexagonal array. This review paper was presented at the Conference of the Asian Societies of Cosmetic Scientists 2005 in Bangkok. [source]


    Progressive macular hypomelanosis in Singapore: a clinico-pathological study

    INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 6 2006
    Sujith Prasad W. Kumarasinghe MBBS
    Introduction, Progressive macular hypomelanosis (PMH), a condition of uncertain etiology, is characterized by asymptomatic hypopigmented macules predominantly located on the trunk. To date, there are no reports from South-East Asia concerning this condition. We sought to record the clinical features of PMH in Asian patients, identify etiologic factors, and study the structural and ultrastructural features of melanocytes in this disorder. Methods, Patients who presented to the National Skin Center with acquired, hypopigmented macules on the trunk, without a history of inflammation or infection, were recruited. Erythrocyte sedimentation rate (ESR), complete blood count, fasting blood glucose, liver function tests, skin scrapings for fungi, and skin biopsy specimens (from lesional and normal skin) were obtained. Biopsies were stained with hematoxylin and eosin (H&E), Fontana Masson, an immunohistochemical panel for identification of melanocyte differentiation antibodies (HMB 45, Melan A, and S100) and CD 68. Electron microscopy (EM) was also performed. The patients were evaluated every 3 months. Results, During a 9 month period, eight patients (all Chinese) presented with hypopigmented, ill-defined, confluent macules involving the lower aspect of the trunk. There were four men and four women, and the mean age was 25.9 years (range 19,45 years). Skin scrapings were negative for fungi and laboratory tests were normal. Microscopic evaluation of skin biopsy speciments showed reduced pigmentation of lesional as compared with normal appearing skin, but H&E-stained sections revealed only minimal histologic differences between lesional and normal skin. EM demonstrated a statistically significant (P = 0.047, Wilcoxon Signed Rank Test, Wilcoxon 95% CI 0.02,0.62) higher ratio of stage IV and late stage III (dark) melanosomes in normal vs. lesional skin. Conclusions, PMH may occur among young adults in Singapore. Its etiology is uncertain. The melanin content of lesional skin appears to be less than that in normal sites. EM shows a higher ratio of immature melanosomes in lesional vs. normal skin. [source]


    Juvenile psoriatic arthritis with nail psoriasis in the absence of cutaneous lesions

    INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 1 2000
    Carola Duran-McKinster MD
    A 4-year-old white boy without a significant family history had morning stiffness and painful swelling of his left knee and ankle, right elbow, and dorsolumbar region of 2 months' evolution. The following laboratory studies were within normal limits: complete blood cell count, C-reactive protein (CRP), latex, antistreptolysin, and antinuclear antibodies. Rheumatoid factor was negative and an increase in the erythrocyte sedimentation rate (ESR) was detected (56 mm/h). The pediatric department made an initial diagnosis of juvenile rheumatoid arthritis, and treatment with acetylsalicylic acid at 100 mg/kg/day and naproxen at 10 mg/kg/day was started. A thick, yellowish toenail was diagnosed as onychomycosis. No mycologic investigations were performed. Intermittent episodes of painful arthritis of different joints were present. The radiographic features of the peripheral joints included: narrow joint spaces, articular erosions, soft tissue swelling, and diffuse bony demineralization. Characteristic bilateral sacroiliitis and a swollen tendon sheath on the left ankle were detected. At 11 years of age the nail changes had extended to five other toenails and to four fingernails, were yellow,brown in color, and showed marked subungual hyperkeratosis ( Figs 1, 2). The rest of the nails showed significant nail pitting. Trials of griseofulvin alternated with itraconazole in an irregular form for five consecutive years resulted in no clinical improvement, which prompted a consultation to our dermatology department. On three different occasions, KOH nail specimens were negative for fungus, but the presence of parakeratotic cells aroused the suspicion of psoriasis. A complete physical examination was negative for psoriatic skin lesions. A nail bed biopsy specimen was characteristic of nail psoriasis ( Fig. 3). Figure 1. Thickened nails with severe subungual hyperkeratosis in five fingernails Figure 2. Secondary deformity of nail plate. No "sausage" fingers were observed Figure 3. Light microscopic appearance of a nail biopsy specimen showing parakeratotic hyperkeratosis, elongation of interpapillary processes, and Munroe abscess (arrow) (hematoxylin and eosin stain, ×40) The following human leukocyte antigens (HLAs) were positive: A9, A10, B12, B27, Cw1, Bw4, DR6, DR7, DQ1, DQ2, and DR53. A diagnosis of juvenile psoriatic arthritis associated with nail psoriasis was made. Toenail involvement became so painful that walking became very difficult. Occlusive 40% urea in vaseline applied to the affected toenails for 48 h resulted in significant improvement. Currently, the patient is 20 years old with nail involvement, but no psoriatic skin lesions have ever been observed. [source]


    ESR detection of irradiated broad bean (Vicia faba L.) and kinetics of the radiation induced free radical and Mn2+ signals

    INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2003
    Mustafa Polat
    Summary An ESR (Electron Spin Resonance) investigation on irradiated dry broad bean gave a spectrum which was composed of an equally spaced sextet and a single resonance line. These lines appeared at g = 2.0045 (±0.0005) and originated from Mn2+ ions and radiation induced radicals, respectively. Ground broad bean was used throughout the work to avoid any artefacts arising from a microwave cavity filling factor. Free radical signal intensity was observed to increase exponentially in relation to the increase in absorbed dose over the dose range 1.25,15 kGy. Although the Mn2+ signal increases below room temperature, the signal due to the natural and radiation induced radicals decreases. Above room temperature, they both decreased and these decreases were irreversible. The kinetics of these decreases were studied in detail over a temperature range of 308,373 K by annealing samples at different temperatures for various times. [source]


    Electron spin resonance studies on ,-irradiated coffee bean parts

    INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 1 2003
    Brij Bhushan
    Summary Using electron spin resonance (ESR) free radicals, present naturally or formed after ,-irradiation of parts of coffee bean, were examined by entrapping the sample in potassium chloride powder in ESR quartz tubes. The ESR signal at g=2.002 was more prominent in the spermoderm than in the whole seed portion of the coffee beans. The ,-irradiation of coffee beans with doses of 5 or 10 kGy, normally used for decontamination, resulted in a dose-dependent increase of a signal at g=2.002 which was accompanied by a weak triplet (aH c. 3.0 mT), and which was also more prominent in the spermoderm. While short-term storage (24 h at 25 ± 0.5 °C) of irradiated beans resulted in a substantial loss of signal at g=2.002, annealing at 50 ± 0.5 °C for 16 h increased this signal intensity in greater proportion than caused by irradiation alone, suggesting that generation of free radicals in the two varieties of coffee beans is not unique to the irradiation processing alone. [source]


    Interleukin-10 gene promoter polymorphism in Polish rheumatoid arthritis patients

    INTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 4 2010
    A. Paradowska-Gorycka
    Summary Interleukin (IL)-10 is an important multifunctional cytokine with both anti-inflammatory and immunoregulatory effects in rheumatoid arthritis (RA). In the present study, we evaluated the frequency and potential impact of IL-10 promoter polymorphisms on susceptibility to and severity of RA in Polish in , patients with a high disease activity (mean DAS 28 C-reactive protein 5.25). DNA was obtained from 244 RA patients and 106 healthy controls. The ,592C/A and ,1082G/A IL-10 gene polymorphisms were amplified by polymerase chain reaction with restriction endonuclease mapping. The frequency of the IL-10-592CA, -592AA genotypes (respectively: 30% vs 5% and 7% vs 0%) and allele ,592A (37% vs 5%) were significantly higher in RA patients as compared with a control group. We did not find any association of the IL-10-592C/A genotype distribution with disease parameters, except for an increased ESR (erythrocyte sedimentation rate) in patients with the ,592CC genotype as compared with those with ,592CA or ,592AA genotypes (P = 0.01). The frequency of the IL-10-1082GG genotype was lower (P = 0.0001), and that of the IL-10-1082GA genotype was higher (P = 0.009) in RA patients comparing with the control group. In RA patients with ,1082GA or ,1082AA genotypes the time duration of the disease (P = 0.03), Health Assessment Questionnaire (HAQ) Score (P = 0.04) and PLT count (P = 0.001) were significantly increased as compared with subjects with ,1082GG genotype. Presented findings indicate that IL-10-592C/A and IL-10-1082G/A polymorphisms may be considered genetic risk factors for RA susceptibility and severity. [source]


    Evaluation of Ves-Matic Cube 200 , an automated system for the measurement of the erythrocyte sedimentation rate

    INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1p2 2010
    E. PEROVIC
    Summary Ves-Matic Cube 200 is fully automated analyzer that performs erythrocyte sedimentation rate (ESR) measurement using the standard ethylenediaminetetraacetic acid blood sample tube, thus markedly reducing the analytical time and avoiding the need for an extra blood sample. The aim of this study was to assess the automatic Ves-Matic Cube 200 system for the measurement of ESR in comparison with the original International Council for Standardization in Hematology reference method (Westergren). The evaluation comprised accuracy which was established using a 95% confidence interval (CI) for the mean difference between Ves-Matic Cube 200 and Westergren method (mean of difference: 0.47 ± 6.84 mm/h; 95% CI: ,0.376 to 1.325 mm/h), within-run imprecision for samples with ESR values of 9, 42 and 95 mm/h (coefficients of variation: 9.19%, 13.88% and 5.66%, respectively) and method comparison (, = 0.95; Passing-Bablok regression equation: Y = ,0.0435 + 1.0435 X; bias: ,0.5; limits of agreement: ,13.9 to 12.9). Stability was estimated after 24 h storage either at 4 °C and room temperature (mean of differences: ,1.91 mm/h; 95% CI: ,4.852 to 1.037 mm/h and mean of differences: ,12.48 mm/h; 95% CI: ,16.580 to ,8.390 mm/h, respectively). The obtained results suggest that the Ves-Matic Cube 200 automated analyzer is reliable system for the measurement of ESR in clinical laboratories. [source]