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Complex Species (complex + species)
Kinds of Complex Species Selected AbstractsStructural, Spectroscopic, and Proton-Coupled Electron-transfer Behavior of Pyrazolyl-3,5-bis(benzimidazole)-Bridged Homo- and Heterochiral RuIIRuII, OsIIOsII, and OsIIRuII 2,2,-Bipyridine ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 4 2010Sujoy Baitalik Abstract The homo- and heterobimetallic complexes [(bpy)2MII(H2pzbzim)M,II(bpy)2](ClO4)3·nH2O (1, 3, 5) and their corresponding deprotonated complexes [(bpy)2MII(pzbzim)M,II(bpy)2](ClO4)·nH2O (2, 4, 6) [where MII, M,II = Ru (1, 2) = Os (3, 4); MII = Os and M,II = Ru (3, 5); bpy = 2,2,-bipyridine; H3pzbzim = pyrazole-3,5-bis(benzimidazole)] were synthesized, separated to their heterochiral (a, ,,/,,) and homochiral (b, ,,/,,) diastereoisomers, and characterized by elemental analyses, ESI-MS, and 1H NMR spectroscopy. The X-ray structures of 1a, 3a, and 5a show the involvement of two pyridine rings of two bpy ligands in strong intramolecular nonbonded ,,, interaction. The occurrence of a C,H···, interaction between an aromatic C,H and the ,-cloud of a pyridine ring leads to strong electronic shielding of this proton (1H NMR). In all cases, the two diastereoisomers show practically no differences in their absorption spectra, redox potentials, and pK values. The large shifts in the E1/2 values to less positive potentials and substantial redshifts in the MLCT bands that occur on deprotonation of 1, 3, and 5 are energetically correlated. From the profiles of E1/2(1), (2) vs. pH over the pH range 1,12, the equilibrium constants and standard redox potentials for all the complex species in the metal oxidation states II·II, II·III, and III·III and the bridged ligand in the protonation states H2pzbzim,, Hpzbzim2,, and pzbzim3, have been evaluated. Using these values the bond dissociation free energies for the benzimidazole N,H bonds have been estimated. Spectroelectrochemical studies have been carried out for 1a, 3a, and 5a in the range 400,1100 nm. With stepwise oxidation of the metal centers replacement of MLCT bands by LMCT bands occur gradually with the observation of sharp isosbestic points. In the case of 1a, a band observed at ,max = 910 nm for the RuIIRuIII species has been ascribed to intervalence charge transfer (IVCT) transition. [source] Metal Complexes of 4,11-Dimethyl-1,4,8,11-tetraazacyclotetradecane-1,8-bis(methylphosphonic acid) , Thermodynamic and Formation/Decomplexation Kinetic StudiesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2009Ivona Svobodová Abstract The macrocyclic ligand with two methylphosphonic acid pendant arms, 4,11-dimethyl-1,4,8,11-tetraazacyclotetradecane-1,8-bis(methylphosphonic acid) (1,8-H4Me2te2p, H4L3), was synthesized by a new simple approach. The product of the reaction of quarternized formaldehyde cyclam aminal with the sodium salt of diethyl phosphite was hydrolyzed to give a very high yield of the title ligand. The (H6L3)2+ cation in the solid state is protonated on all ring nitrogen atoms and on each phosphonate group. In the solid-state structure of [Cu(H3L3)][Cu(H2L3)]PF6·3H2O, neutral as well as positively charged complex species are present. Molecular structures of both species are very similar having the copper(II) ion in a coordination environment between square-pyramidal and trigonal-bipyramidal arrangements (, = 0.43 and 0.48) with one pendant arm non-coordinated. The ligand forms stable complexes with transition-metal ions showing a high selectivity for divalent copper atoms. The formation of complexes of the ligand with CuII, ZnII and CdII is fast, confirming the acceleration of complexation due to the presence of the strongly coordinating pendant arms. Acid-assisted decomplexation is fast for all three metal ions. Therefore, the copper(II) complex is not suitable for medicinal applications employing copper radioisotopes, but the title ligand motive can be employed in copper(II) separation. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Structure Comparison of Early and Late Lanthanide(III) Homodinuclear Macrocyclic Complexes with the Polyamine Polycarboxylic Ligand H8OHECEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2004Ulrike A. Böttger Abstract The solid-state structures of two new homodinuclear chelate complexes with the late lanthanide(III) ions Yb and Lu, [Na2(Yb2OHEC)].14.5H2O (1), and [Na2(Lu2OHEC)].14.5H2O (2) (H8OHEC = 1,4,7,10,14,17,20,23-octaazacyclohexacosane- 1,4,7,10,14,17,20,23-octaacetic acid), have been determined by X-ray crystal structure analysis. Each lanthanide(III) ion is coordinated by eight donor atoms of the ligand and the geometry of the coordination polyhedron approaches a bicapped trigonal prism. These structures are compared with those of the homodinuclear chelate complexes with the same ligand and the mid to early lanthanide(III) ions Gd, Eu, La and also Y. A distinctive structural change occurs across the lanthanide series. The centrosymmetric mid to early lanthanide(III) complexes are all ninefold-coordinated in a capped square antiprismatic arrangement with a water molecule coordinated in a prismatic position. This structure is maintained in aqueous solution, together with an asymmetric minor isomer. The late lanthanide(III) OHEC complexes not only lack the inner-sphere water, but the change of coordination sphere also results in a loss of symmetry of the whole complex molecule. The observed change of coordination mode and number of the lanthanide ion may offer a geometric model for the isomerization process in eight- and ninefold-coordinated complex species that are isomers in a possible coordination equilibrium observed by NMR in aqueous solution. This model may also explain the intramolecular rearrangements necessary during water exchange in the inner coordination sphere of the complex [(Gd2OHEC)(H2O)2]2, through a slow dissociative mechanism. Protonation constants of the H8OHEC ligand and complex formation constants of this ligand with GdIII, CaII, CuII and ZnII have been determined by solution thermodynamic studies. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Pro-inflammatory biomarkers during experimental gingivitis in patients with type 1 diabetes mellitus: a proof-of-concept studyJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2010Giovanni E. Salvi Abstract Aim: To compare gingival crevicular fluid (GCF) biomarker levels and microbial distribution in plaque biofilm (SP) samples for subjects with type 1 diabetes (T1DM) versus healthy subjects without diabetes during experimental gingivitis (EG). Materials and Methods: A total of nine T1DM patients and nine healthy controls of age and gender similar to the T1DM patients were monitored for 35 days during EG. Hygiene practices were stopped for 3 weeks, and GCF, SP, plaque index (PI) and gingival index were determined. IL-1,, IL-8, MMP-8 and MMP-9 were quantified by enzyme-linked immunosorbent assay, and SP samples were assessed by DNA,DNA hybridization for a panel of 40 subgingival microbial species. Results: IL-1, levels in T1DM patients were elevated compared with healthy individuals, and showed differences between groups at 7,21 days while healthy patients showed IL-1, increases from baseline to 14,21 days (p<0.05). Differences were observed in MMP-9 levels between patients with and without T1DM at 7,14 days (p<0.05). Orange complex species and PI measurements displayed a superior correlation with biomarker levels when compared with other complexes or clinical measurements during EG. Conclusions: The mean GCF biomarker levels for IL-1, and MMP-8 were most significantly elevated in T1DM subjects compared with healthy individuals during EG, not resulting from differences in the mean PI or microbial composition. [source] Scaling and root planing, systemic metronidazole and professional plaque removal in the treatment of chronic periodontitis in a Brazilian population II , microbiological resultsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 4 2005L. H. Carvalho Abstract Objective: The current investigation evaluated changes in levels and proportions of 39 bacterial species in subgingival plaque samples after scaling and root planing (SRP) alone or in combination with systemic metronidazole and/or professional cleaning in subjects with chronic periodontitis. Methods: Forty-four adult subjects (mean age 45±6 years) with periodontitis were randomly assigned in four treatment groups, a control (C, n=10) that received SRP and placebo and three test groups treated as follows: T1 (n=12): SRP and metronidazole (M, 400 mg tid) for 10 days; T2 (n=12): SRP, weekly professional supragingival plaque removal for 3 months (PC) and placebo; and T3 (n=10): SRP, M and PC. Subgingival plaque samples were taken from seven sites per subject at baseline and 90 days post-therapy. Counts of 39 subgingival species were determined using checkerboard DNA,DNA hybridization. Significance of differences over time was determined using the Wilcoxon signed ranks test and among groups using ancova. Results: The mean counts of the majority of the species were reduced post-therapy in the 4 treatment groups. Counts (× 105±SEM) of Porphyromonas gingivalis, Tannerella forsythensis and Treponema denticola were significantly reduced in groups T2 and T3. Levels of beneficial species, such as some Actinomyces species, Veillonella parvula, Streptococcus sanguis, Streptococcus oralis and Streptococcus gordonii were minimally affected in levels when the combined therapy was applied (T3). Mean proportions of red complex species decreased from 18.4% at baseline to 3% at 90 days post-therapy in group T3 (p<0.01), from 25.8% to 2.3% in group T2 (p<0.01), from 17.7% to 5.6% in group T1 (p<0.05) and from 19.4% to 8.8% in group C (NS). Proportions of the suspected periodontal pathogens from the orange complex were also markedly reduced in groups T2 and T3. Conclusions: All treatments reduced counts and proportions of red complex species. Adjunctive therapy appeared to have a greater effect and also affected members of the orange complex. [source] Relationship between periodontal pocket sulfide levels and subgingival speciesJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 11 2003G. Torresyap Abstract Background: Many species implicated in the pathogenesis of periodontal disease produce volatile sulfur compounds (VSC). This investigation examined the relationship between levels of sulfide and subgingival bacterial species in the same periodontal pockets. Material and Methods: Twenty chronic periodontitis subjects were measured clinically at six sites per tooth for plaque, gingivitis, bleeding on probing, suppuration, pocket depth and attachment level. Subgingival plaque samples, taken from the mesial aspect of each tooth, were individually analyzed for their content of 40 bacterial species using checkerboard DNA,DNA hybridization. Sulfide levels were measured at the same sites using a Diamond Probe/Perio 2000 system. Clinical and microbiological data were averaged for sulfide-positive and -negative sites separately in each subject and then averaged across subjects. Significance differences in clinical and microbial parameters between sulfide-positive and -negative sites were sought using the Wilcoxon signed ranks test. Results: Mean total DNA probe counts (×105, ±SEM) at sulfide-negative and -positive sites were 44.0±9.9 and 65.0±13.3, respectively (p<0.01). Seventeen species were found at significantly higher levels in sulfide-positive than -negative sites. These included abundant producers of VSC such as members of the genera Fusobacterium, Campylobacter, Prevotella, Treponema and Eubacterium, and Bacteriodes forsythus, Selenomonas noxia and Propionibacterium acnes. Prevotella intermedia, Bacteriodes forsythus, Prevotella nigrescens, Fusobacterium nucleatum ss vincentii and Treponema denticola exhibited the greatest difference in mean counts between sulfide-negative and -positive sites. Orange and red complex species were at higher counts at shallow (<4 mm) sulfide-positive than shallow sulfide-negative sites. Although not statistically significant, mean clinical parameters were somewhat higher at sulfide-positive than sulfide-negative sites. Conclusions: Intra-pocket sulfide levels reflect the levels of sulfide-producing species and may provide useful diagnostic information. Zusammenfassung Grundlagen: Viele Spezies, die mit der Pathogenese der Parodontalerkrankung verbunden sind produzieren flüchtige Schwefelkomponenten (VSC). Diese Studie untersuchte die Verbindung zwischen dem Sulfid-Niveau und subgingivalen Spezies in den gleichen parodontalen Taschen. Methode: 20 Patienten mit chronischer Parodontitis wurden an 6 Stellen pro Zahn klinisch befundet hinsichtlich Plaque, Gingivitis, BOP, Eiterentleerung, Taschentiefe und Attachmentniveau. Unter Verwendung der Schachbrett-DNA,DNA-Hybridisierung wurden subgingivale Plaqueproben von der mesialen Stelle eines jeden Zahns individuell hinsichtlich des Vorkommens von 40 bakteriellen Spezies untersucht. An der gleichen Stelle wurde mittels des Diamond Probe/Perio 2000 Systems das Niveau des Sulfids gemessen. Von den klinischen und mikrobiologischen Daten wurden bei jedem Patienten getrennt für Sulfid-positiv und Sulfid-negativ ein Durchschnitt gebildet und anschließend der Durchschnitt für alle Patienten berechnet. Nach signifikanten Unterschieden in den klinischen und mikrobiologischen Parametern zwischen Sulfid-positiven und Sulfid-negativen Stellen wurde unter Verwendung des Wilcoxon signed ranks Test gesucht. Ergebnisse: Die mittlere Bakterienanzahl mit Gesamt-DNA-Sonden (× 105, ±SEM) betrug an den Sulfid-negativen Stellen und Sulfid-positiven Stellen 44.0±9.9 bzw. 65.0±13.3 (p<0.01). Bei 17 Spezies wurde ein signifikant höheres Niveau in den Sulfid-positiven Stellen vorgefunden. Die umfasste Bakterien die reichlich VSC produzieren, wie Mitglieder der Genera Fusobacterium, Campylobacter, Prevotella, Treponema und Eubacterium und B. forsythus, S. noxia und P. acnes. P. intermedia, B. forsythus, P. nigrescens, F. nucleatum ssvincentii und T. denticola zeigten den größten Unterschied zwischen Sulfid-positiven und Sulfid-negativen Stellen in der durchschnittlichen Bakterienanzahl. Spezies des orangen und roten Komplexes lagen in höherer Anzahl in flachen (<4 mm) Sulfid-positiven, als in flachen Sulfid-negativen Taschen vor. Obwohl statistisch nicht signifikant, lagen die durchschnittlichen klinischen Parameter bei den Sulfid-positiven etwas höher als bei den Sulfid-negativen Taschen Schlussfolgerungen: Die innerhalb der Taschen gemessenen Sufiid-Niveaus spiegeln das Niveau der Sulfid-produzierenden Spezies wieder und könnten eine nützliche diagnostische Information liefern. Résumé Plusieurs espèces impliquées dans la pathogenèse de la maladie parodontale produisent des composés de sulfate volatiles (VSC). Cette étude examine la relation entre les niveaux de sulfate et les espèces bactériennes sous-gingivales dans les mêmes poches parodontales. Vingt sujets avec parodontite chronique ont subi un examen clinique au niveau de six sites par dent pour la plaque dentaire, la gingivite, la profondeur de poche au sondage (BOP), la suppuration, la profondeur de poche et le niveau d'attache. Des échantillons de plaque sous-gingivale prélevés en mésial de chaque dent ont été analysés individuellement pour leur contenu de 40 espèces bactériennes à l'aide de l'hybridisation ADN-ADN croisée. Les niveaux de sulfate ont été mesurés au niveau des mêmes sites par le système de sonde Diamond/Perio 2000. Les moyennes des données cliniques et microbiologiques ont étéétablies pour les sites sulfate positif et négatif chez chaque sujet et par sujet. Des différences significatives dans les paramètres cliniques et microbiologiques entre les sites sulfate positif et négatif ont été observées via le test de Wilcoxon. Les moyennes totales des comptes de la sonde ADN (x105,+/,ES) au niveau des sites sulfate négatif et positif étaient respectivement de 44,0 +/,9,9 et 65,0+/,13,3 (p<0,01). Dix sept espèces ont été trouvées à des niveaux hautement plus significatifs dans des sites sulfate positif que négatif. Ceux-ci comprennaient d'abondants producteurs de VSC tels que les Fusobacterium, Catnpylobacter, Prevotella, Treponema, Eubacterium, B. forsythus, S. noxia etP. acnes, P. intermedia, B. forsythus, P. nigrescens, F. nucleatum ss vincentii et T. denticola qui montraient la plus grande différence dans la moyenne des comptes entre les sites sulfate négatif et positif. Les espèces complexe orange et rouge étaient plus nombreuses dans les sites de faible profondeur (<4 mm) sulfate positif que dans les sites peu profonds sulfate négatif. Bien que statistiquement non significative la moyenne des paramètres cliniques a été quelque peu plus élevée au niveau des sites sulfate positif qu'au niveau des négatifs. Les niveaux de sulfate intrapoche reflètent les niveaux des espèces produisant du sulfate et pourraient apporter une information de diagnostic pratique. [source] Microbial composition of supra- and subgingival plaque in subjects with adult periodontitisJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 10 2000Laurie Ann Ximénez-Fyvie Abstract Background, aims: The purpose of the present study was to compare and relate the microbial composition of supra and subgingival plaque in 23 adult periodontitis subjects (mean age 51±14 years). Methods: A total of 1,170 samples of supra and subgingival plaque were collected from the mesial aspect of every tooth (up to 28 supra and 28 subgingival samples) from each subject and evaluated for the presence and levels of 40 bacterial taxa using whole genomic DNA probes and checkerboard DNA-DNA hybridization. Clinical assessments including dichotomous measures of gingival redness, bleeding on probing, plaque accumulation and suppuration, as well as duplicate measures of pocket depth and attachment level, were made at 6 sites per tooth. The counts (levels), % DNA probe count (proportion) and % of sites colonized (prevalence) of each species in supra and separately in subgingival plaque were computed for each subject. Significance of differences between supra and subgingival plaque for each species was sought using the Wilcoxon signed ranks test and adjusted for multiple comparisons. Results: All 40 taxa were detected in both supra and subgingival plaque. Actinomyces species were the most prevalent taxa in both habitats. 75 to 100% of supra and 62 to 100% of subgingival sites were colonized by at least one of the 5 Actinomyces species. Supragingival samples exhibited significantly higher counts of Actinomyces naeslundii genospecies 1, Actinomyces israelii, Actinomyces odontolyticus, Neisseria mucosa, Streptococcus gordonii, Capnocytophaga ochracea and Capnocytophaga sputigena when compared with mean counts in subgingival samples taken from the same tooth surfaces. Subgingival plaque samples presented significantly higher counts of Prevotella nigrescens, Prevotella intermedia, Bacteroides forsythus and Porphyromonas gingivalis. Subgingival samples exhibited a significantly higher proportion of "red" and "orange complex" species, while supragingival plaque exhibited higher proportions of "green" and "purple" complex species as well as Actinomyces species. Suspected periodontal pathogens could be detected in supragingival plaque from sites where subgingival samples were negative for the same species. Conclusions: The data indicate that supragingival plaque can harbor putative periodontal pathogens, suggesting a possible rôle of this environment as a reservoir of such species for the spread or reinfection of subgingival sites. [source] Factors affecting human supragingival biofilm composition.JOURNAL OF PERIODONTAL RESEARCH, Issue 4 2009Background and Objective:, Little is known about the factors that affect the microbial composition of supragingival biofilms. This study was designed to examine the relationship between total DNA probe counts of supragingival biofilm samples, clinical parameters and supragingival biofilm composition. Material and Methods:, Supragingival plaque samples were taken from 187 systemically healthy adult subjects (n = 4745 samples). All samples were individually analyzed for their content of 40 bacterial species using checkerboard DNA,DNA hybridization. The relationship between total DNA probe counts and microbial composition was examined by subsetting the data into 10 groups based on 10 percentile increments of the total DNA probe counts. Differences among groups in terms of species counts and proportions were sought, as well as relationships of total plaque DNA probe count and clinical parameters. Results:, There was a wide distribution in mean total DNA probe counts among the 187 subjects. With increasing total plaque levels there was a change in the proportions of individual species and microbial complexes. ,Small plaques' were characterized by high proportions of species in the yellow, orange, purple and ,other' complexes; plaques of moderate mass were characterized by high proportions of Actinomyces and purple complex species, while ,large plaques' exhibited increased proportions of green and orange complex species. Measures of gingival inflammation, pocket depth and recession were significantly positively associated with total DNA probe counts. Increased plaque numbers were related to increased pocket depth irrespective of presence or absence of gingival inflammation. Conclusion:, The proportions of individual species and microbial complexes in supragingival biofilms are influenced by the total numbers of organisms in the biofilm. [source] Variability in starch physicochemical and functional properties of yam (Dioscorea sp) cultivated in Ivory CoastJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2004N'Guessan Georges Amani Abstract An Erratum has been published for this article in Journal Of the Science of Food and Agriculture 85(5), 889 (2005). Native starches were extracted from 21 cultivars of four yam species representative of the yam population of Ivory Coast. They were first characterized for their proximate composition, starch physico-chemical properties (amylose content, particle size distribution, crystallinity, thermal properties and intrinsic viscosity). Some functional properties (swelling, solubility and pasting behaviour and paste clarity) were then determined. Analysis of variance and principal component analysis showed that three homogenous groups could be distinguished, mainly based on starch physico-chemical properties. The first group contained all yam starches of the D alata and the D cayenensis-rotundata complex species. It was characterized by a large diameter grain (approximately 25 µm), a high amylose content (around 25% db), a high intrinsic viscosity (mean of 190 cm3 g,1), and a high apparent viscosity and clarity of the paste. The second group contained the D esculenta varieties, characterized by a small granule size (diameter 6 µm), a low intrinsic viscosity (121 cm3 g,1), a high gelatinization enthalpy change (19 J g,1) and a low paste viscosity. The D dumetorum sample differed from the D esculenta group by having a pure A-type crystalline form and an opaque paste. A multiple regression showed that the volume fraction of the dispersed phase and native granule size (or amylose content) could account for close to 80% of the variability of paste apparent viscosity. Gel clarity appeared mainly linked to granule size, small granules from D dumetorum and D esculenta giving the most opaque gels. Copyright © 2004 Society of Chemical Industry [source] Isolation and characterization of microsatellite loci in a cooperatively breeding corvid, the American crow (Corvus brachyrhynchos)MOLECULAR ECOLOGY RESOURCES, Issue 1 2007L. A. SCHOENLE Abstract We describe 11 microsatellite loci isolated from the American crow (Corvus brachyrhynchos), the most wide-spread cooperatively breeding bird in North America. Polymorphism at these loci ranged from four to 43 alleles, and observed heterozygosities from 0.53 to 0.92. Genetic parentage analyses using these markers will allow us to describe the mating system of this common but socially complex species, and to interpret their behavioural interactions in light of relatedness. [source] The microbiota on different oral surfaces in healthy childrenMOLECULAR ORAL MICROBIOLOGY, Issue 3 2009W. Papaioannou Introduction:, Knowledge of the early oral colonization patterns could provide a better understanding of oral biofilm development and disease initiation that in turn could be the basis for early preventive programmes. Methods:, Microbial samples were collected from five different oral habitats from a total of 93 children (age 3,12 years), attending the Dental School of the University of Athens, who were split into three age groups. A total of 38 microbial species were sought out by the checkerboard DNA,DNA hybridization technique. Results:, All of the test species, except Parvimonas micra and Porphyromonas gingivalis, differed significantly among sample locations providing quite distinct microbial profiles for the different oral surfaces. Supragingival and subgingival plaque had similar profiles and exhibited higher proportions of Actinomyces species and Green complex while soft tissue samples were dominated by streptococci of the Yellow complex. The profiles of the tongue dorsum and saliva were also similar. Many of the species were in similar proportions in all three age groups for a given location. Periodontal pathogens showed increases in proportions with increasing age. Specifically, the Red complex species (Tannerella forsythia, P. gingivalis, Treponema denticola) showed a significant increase in proportion with age (P < 0.05) in all sample locations. Conclusions:, The results showed a pattern of colonization in children similar to that previously found in adults. Differences in the profile between age groups suggest a gradual maturation of the oral microbiota, with it being made up of an increasing number of Orange and Red complex species. [source] Increased interleukin-18 in gingival crevicular fluid from periodontitis patientsMOLECULAR ORAL MICROBIOLOGY, Issue 2 2008C. M. Figueredo Introduction:, This study aimed to measure the levels of interleukin-18 (IL-18) in inflamed shallow sites and inflamed deep sites in patients with periodontitis and to compare the data with results from inflamed shallow sites in patients with gingivitis. A secondary aim was to examine the composition of the subgingival microbiota in the sampled sites. Methods:, Gingival crevicular fluid was collected from five gingivitis sites and five periodontitis sites from 18 patients with chronic periodontitis, and from five gingivitis sites from 15 patients with gingivitis. Samples from each site category were pooled and IL-18 levels were measured using an enzyme-linked immunosorbent assay. The subgingival microbiota was analyzed by checkerboard DNA,DNA hybridization. Results:, All clinical parameters and gingival crevicular fluid volumes were higher in periodontitis sites compared with gingivitis sites from patients with periodontitis and gingivitis. The total amount of IL-18 was higher in periodontitis sites than gingivitis sites in both periodontitis (P = 0.018) and gingivitis (P = 0.002) patients and was higher in gingivitis sites from periodontitis patients than in those from gingivitis patients (P = 0.015). There were higher levels of Tannerella forsythia, Porphyromonas gingivalis, and Treponema denticola (red complex species) in periodontitis sites compared with gingivitis sites in both the periodontitis and gingivitis patients (P < 0.001). Conclusion:, Levels of IL-18 were higher in patients with chronic periodontitis compared with patients with gingivitis, even at sites with similar pocket depths. The presence of similar levels of red complex species in gingivitis sites from periodontitis patients and from gingivitis patients suggested that the higher levels of IL-18 were not associated with a different microbial challenge. [source] Distribution of 10 periodontal bacterial species in children and adolescents over a 7-year periodORAL DISEASES, Issue 7 2008K Nakano Objective:, There is scant information available regarding the distribution of periodontal bacterial species in children and adolescents over an extended period. The purpose of this study was to compare bacterial profiles in the same individuals over a period of 7 years. Subject and methods:, Twenty-six children and adolescents from whom dental plaque and saliva specimens were obtained during both the first (1999,2000) and second (2006,2007) periods, were analyzed. Bacterial DNA was extracted from each specimen and the presence of 10 periodontal bacterial species was determined using a PCR method, with a focus on the red complex species of Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia. Results:, Subjects with red complex species in saliva specimens obtained during the second collection possessed a significantly higher number of total bacterial species than those without. The detection rate of the red complex species in the second collection period samples was significantly greater in subjects who had two or more species detected in samples taken during the first collection compared with the other subjects. Conclusion:, Subjects possessing red complex species may be at possible risk for infection with a high number of periodontal bacterial species during adolescent and younger adult years. [source] Effect of organic additives on formation and structure of polyelectrolyte-oppositely charged surfactant complexes,POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 11-12 2006J. A. Zakharova Abstract Effect of butanol and Triton X-100 on formation, supramolecular organization and local dynamics of poly(N -ethyl-4-vinylpyridinium)-dodecyl sulfate complexes have been studied by UV spectroscopy, high-speed sedimentation, laser light scattering and electron spin resonance (ESR) spectroscopy. It was found that solubilization of butanol promotes aggregation of the complex species in solution and results in contraction of the region in which water-soluble complexes are formed. On the contrary, highly aggregated complexes disaggregate up to molecularly dispersed state upon addition of Triton X-100. It was found that under the experimental conditions neither butanol (up to 3,wt%) nor Triton X-100 ([Triton X-100]/[sodium dodecylsulfate],,,1:1) cause destruction of the complexes. The results of ESR spin probe and spin label studies show that in both cases supramolecular realignments are accompanied by a slight increase of the local molecular mobility of surfactant ions in the complex micelles, segmental mobility of polyelectrolyte being unchanged. Copyright © 2006 John Wiley & Sons, Ltd. [source] Theoretical and experimental study of the complexation of valinomycin with ammonium cationBIOPOLYMERS, Issue 12 2008í Dybal Abstract The interactions of valinomycin, macrocyclic depsipeptide antibiotic ionophore, with ammonium cation NH4+ have been investigated. Using quantum mechanical density functional theory (DFT) calculations, the most probable structure of the valinomycin-NH4+ complex species was predicted. In this complex, the ammonium cation is bound partly by three strong hydrogen bonds to three ester carbonyl oxygen atoms of valinomycin and partly by somewhat weaker hydrogen bonds to the remaining three ester carbonyl groups of the valinomycin ligand. The strength of the valinomycin-NH4+ complex was evaluated experimentally by capillary affinity electrophoresis. From the dependence of valinomycin effective electrophoretic mobility on the ammonium ion concentration in the background electrolyte, the apparent binding (association, stability) constant (Kb) of the valinomycin-NH4+ complex in methanol was evaluated as log Kb = 1.52 ± 0.22. © 2008 Wiley Periodicals, Inc. Biopolymers 89: 1055,1060, 2008. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] Binding of quercetin with human serum albumin: A critical spectroscopic studyBIOPOLYMERS, Issue 6 2003Bidisa Sengupta Abstract Flavonols are plant pigments that are ubiquitous in nature. Quercetin (3,3,,4,,5,7-pentahydroxyflavone) and other related plant flavonols have come into recent prominence because of their usefulness as anticancer, antitumor, anti-AIDS, and other important therapeutic activities of significant potency and low systemic toxicity. Quercetin is intrinsically weakly fluorescent in aqueous solution, showing an emission maximum at ,538 nm. Upon binding to human serum albumin (HSA), quercetin undergoes dramatic enhancement in its fluorescence emission intensity, along with the appearance of dual emission behavior, consisting of normal and excited-state proton transfer (ESPT) fluorescence. In addition, the occurrence of a third emitting species has been noted for the first time. This is attributed to a electronic ground-state complex formed in the protein environment. High values of the fluorescence anisotropy (r) are obtained in the presence of HSA for the ESPT tautomer (r = 0.18), as well as the complex species (r = 0.37) of quercetin, indicating that the precursor ground-state molecules for both these emitting species of quercetin molecules are located in the motionally constrained sites of HSA. The steady-state emission data suggest that quercetin binds to two distinct sites in HSA from which the emissions from the normal tautomer and complex species take place. The preliminary results of studies on emission decay kinetics are also reported herein. Studies by far-UV circular dichroism spectroscopy reveal that binding of quercetin induces no significant perturbation in the secondary structure of HSA. © 2003 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy), 2003 [source] | |||||||||||||