Immunological studies on nucleic acids and their components.8.Antibodies specific to a deoxyribotrinucleotide sequence

Bovine serum albumin conjugates of two trinucleotides, dpTpTpA and dTpTpAp, were prepared by linking the trinucleotides through their end phosphates by the ‘carbodiimide method’. Antibodies were raised in rabbits by injecting the trinucleotide-bovine serum albumin conjugates. Analysis by double diffusion in agar gel, quantitative precipitin reaction and its inhibition by haptens showed clearly the presence of antibodies specific to the whole trinucleotide molecule. The titre of antibodies obtained by the trinucleotide-rabbit serum albumin conjugates with their respective antisera was approximately the same, indicating that linking the trinucleotide through either 5′ or 3′ phosphate does not have an appreciable effect on the titre of antibodies. The results also demonstrate that the nucleotide(s) away from the carrier protein is more immunodominant than the one linked directly to the protein.

Tombstone of Joseph Benjamin; Strangriede Cemetery, R83.8; Hannover Cemeteries Tombs

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Tombstones of Joseph Benjamin and Marianne Benjamin nee Sussmann; Strangriede Cemetery (R 83.8 and R 83.9); Hannover Cemeteries Tombs

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Tombstone of Joseph Benjamin; Strangriede Cemetery (R 83.8); Hannover Cemeteries Tombs

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The scientific basis and development of a matrix metalloproteinase (MMP) -8 specific chair-side test for monitoring of periodontal health and disease from gingival crevicular fluid

Matrix metalloproteinase (MMP) -8, collagenase-2, is a key mediator of irreversible tissue destruction in chronic periodontitis and detectable in gingival crevicular fluid (GCF). MMP-8 mostly originates from neutrophil leukocytes, the first line of defence cells which exist abundantly in GCF, especially in inflammation. MMP-8 is capable of degrading almost all extra-cellular matrix and basement membrane components and is especially efficient against type I collagen. Thus the expression of MMP-8 in GCF could be valuable in monitoring the activity of periodontitis and possibly offers a diagnostic means to predict progression of periodontitis. In this study the value of MMP-8 detection from GCF in monitoring of periodontal health and disease was evaluated with special reference to its ability to differentiate periodontal health and different disease states of the periodontium and to recognise the progression of periodontitis, i.e. active sites. For chair-side detection of MMP-8 from the GCF or peri-implant sulcus fluid (PISF) samples, a dip-stick test based on immunochromatography involving two monoclonal antibodies was developed. The immunoassay for the detection of MMP-8 from GCF was found to be more suitable for monitoring of periodontitis than detection of GCF elastase concentration or activity. Periodontally healthy subjects and individuals suffering of gingivitis or of periodontitis could be differentiated by means of GCF MMP-8 levels and dipstick testing when the positive threshold value of the MMP-8 chair-side test was set at 1000 µg/l. MMP-8 dipstick test results from periodontally healthy and from subjects with gingivitis were mainly negative while periodontitis patients sites with deep pockets ( 5 mm) and which were bleeding on probing were most often test positive. Periodontitis patients GCF MMP-8 levels decreased with hygiene phase periodontal treatment (scaling and root planing, SRP) and even reduced during the three month maintenance phase. A decrease in GCF MMP-8 levels could be monitored with the MMP-8 test. Agreement between the test stick and the quantitative assay was very good (κ = 0.81) and the test provided a baseline sensitivity of 0.83 and specificity of 0.96. During the 12-month longitudinal maintenance phase, periodontitis patients progressing sites (sites with an increase in attachment loss ≥ 2 mm during the maintenance phase) had elevated GCF MMP-8 levels compared with stable sites. General mean MMP-8 concentrations in smokers (S) sites were lower than in non-smokers (NS) sites but in progressing S and NS sites concentrations were at an equal level. Sites with exceptionally and repeatedly elevated MMP-8 concentrations during the maintenance phase were clustered in smoking patients with poor response to SRP (refractory patients). These sites especially were identified by the MMP-8 test. Subgingival plaque samples from periodontitis patients deep periodontal pockets were examined by polymerase chain reaction (PCR) to find out if periodontal lesions may serve as a niche for Chlamydia pneumoniae. Findings were compared with the clinical periodontal parameters and GCF MMP-8 levels to determine the correlation with periodontal status. Traces of C. pneumoniae were identified from one periodontitis patient s pooled subgingival plaque sample by means of PCR. After periodontal treatment (SRP) the sample was negative for C. pneumoniae. Clinical parameters or biomarkers (MMP-8) of the patient with the positive C. pneumoniae finding did not differ from other study patients. In this study it was concluded that MMP-8 concentrations in GCF of sites from periodontally healthy individuals, subjects with gingivitis or with periodontitis are at different levels. The cut-off value of the developed MMP-8 test is at an optimal level to differentiate between these conditions and can possibly be utilised in identification of individuals at the risk of the transition of gingivitis to periodontitis. In periodontitis patients, repeatedly elevated GCF MMP-8 concentrations may indicate sites at risk of progression of periodontitis as well as patients with poor response to conventional periodontal treatment (SRP). This can be monitored by MMP-8 testing. Despite the lower mean GCF MMP-8 concentrations in smokers, a fraction of smokers sites expressed very high MMP-8 concentrations together with enhanced periodontal activity and could be identified with MMP-8 specific chair-side test. Deep periodontal lesions may be niches for non-periodontopathogenic micro-organisms with systemic effects like C. pneumoniae and possibly play a role in the transmission from one subject to another.

Chlorinated Hypoelectronic Dimetallaborane Clusters: Synthesis, Characterization, and Electronic Structures of (eta(5)-C5Me5W)(2)B5HnClm (n=7, m=2 and n=8, m=1)

Pyrolysis of (eta(5)-C5Me5WH3)B4H8, 1, in the presence of excess BHCl2 center dot SMe2 in toluene at 100 degrees C led to the isolation of (eta(5)-C5Me5W)(2)B5H9, 2, and B-Cl inserted (eta(5)-C5Me5W)(2)B5H8Cl, 3, and (eta(5)-C5Me5W)(2)B5H7Cl2, (four isomers). All the Chlorinated tungstaboranes were isolated as red and air and moisture sensitive solids. These new compounds have been characterized in solution by H-1, B-11, C-13 NMR, and the structural types were unequivocally established by crystallographic analysis of compounds 3, 4, and 7. Density functional theory (DFT) calculations were carded out on the model molecules of 3-7 to elucidate the actual electronic structures of these chlorinated species. On grounds of DFT calculations we demonstrated the role of transition metals, bridging hydrogens, and the effect of electrophilic substitution of hydrogens at B-H vertices of metallaborane structures.

1H and 13C NMR spectral studies of C-2 substituted isomeric exo- and endo-5-methyl-bicyclo[3.2.1]octane-6,8-diones

A detailed analysis of the 1H and 13C NMR spectra of C-2 aryl and alkyl/desalkyl substituted isomeric exo- and endo-5-methylbicyclo[3.2.1]octane-6,8-diones is presented. The chemical shift of the C-5 angular methyl, the C-2 alkyl/olefinic (C-10)/C-2 methine protons, the aromatic proton shieldings and the characteristic AMX and ABX spectral pattern of the ketomethylene and bridgehead protons were found to be sensitive to the phenyl ring orientation (anisotropy). These distinctive features could be used for configurational distinction for this class of compounds. With increasing ortho-methoxy substitution on the phenyl ring, considerable deshilelding of the bridgehead proton was observed (ca. 0.6 ppm). Absence of the C-2 alkyl group in the desalkyl isomers resulted in substantial changes in the chemical shifts of different protons. A study of the NMR spectra of the corresponding bicyclic compounds with C-2 methoxy/hydroxy substitution instead of the aryl group revealed that the anisotropy of the phenyl ring and the electronegative oxygen substituents have opposite effects. The 13C NMR spectral assignment of each carbon resonance of C-2 aryl and alkyl/desalkyl substituted isomeric exo- and endo-5-methylbicyclo[3.2.1]octane-6,8-diones and the corresponding C-2 methoxy/hydroxy/chloro and methyl bicyclic compounds are reported. Additional ortho-methoxy substitution on the phenyl ring was found to produce considerable high field shifts of the C-10 and C-1 carbon resonances. A high-field shift was observed for the C-6 and C-8 carbonyl carbons, presumably due to 1,3-dicarbonyl interactions. The chemical shifts of C-1 aromatic, C-10 alkyl and C-2 carbons, which are sensitive to exo/endo isomerism, could be utilized in differentiating a pair of isomers.

Tombstone of Joseph Benjamin; Strangriede Cemetery, R83.8; Hannover Cemeteries Tombs

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Tombstones of Joseph Benjamin and Marianne Benjamin nee Sussmann; Strangriede Cemetery (R 83.8 and R 83.9); Hannover Cemeteries Tombs

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Tombstone of Joseph Benjamin; Strangriede Cemetery (R 83.8); Hannover Cemeteries Tombs

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Structure of (6S,13bR)-1,2,3,5,6,13b-hexahydro-6-isopropyl-8H-pyrrolo[1',2':1,2]pyrazino[3,4,-b]quinazoline-5,8-dione

C17H19N302, monoclinic, P21, a = 5.382 (1), b = 17.534(4), c = 8.198(1)/L ,8 = 100.46(1) °, Z= 2, d,, = 1.323, dc= 1.299 Mg m-3, F(000) = 316, /~(Cu .Ka) = 0.618 mm -1. R = 0.052 for 1284 significant reflections. The proline-containing cispeptide unit which forms part of a six-membered ring deviates from perfect planarity. The torsion angle about the peptide bond is 3.0 (5) ° and the peptide bond length is 1.313 (5)A. The conformation of the proline ring is Cs-Cf~-endo. The crystal structure is stabilized by C-H... O interactions.

Structure of 2-(2,6-Dimethoxyphenyl)-2,5-dimethylbicyclo[3.2. l]octane-6,8-dione

C18H2204, orthorhombic, P212~21, a = 7.343 (4), b = 11.251 (4), c = 19.357 (4)A, Z = 4, Dr, ' = 1.20, D e = 1.254 g cm -3, F(000) = 648, p(Mo Ka) = 0.94 cm -~. X-ray intensity data were collected on a Nonius CAD-4 diffractometer and the structure was solved by direct methods. Full-matrix least-squares refinement gave R = 0.052 (R w = 0.045) for 1053 observed reflections. The stereochemical configuration at C(2) has been shown to be 2-exo-methyl-2-endo- (2,6-dimethoxyphenyl), i.e. (3) in contrast to the structure (2) assigned earlier based on its ~H NMR data.

Margarete Oppenheimer geb. Busch : 29. Mai 1883 - 8. August 1935.

Memorial book with the speeches by Leo Baeck and Hugo Jacobi.

Unusual products of oxidation with Cr(VI) of methyl 5-methyl-7-methoxy-8-isopropyl-3,4-2-naphthoate

Abstract is not available.