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Orofacial granulomatosis is a clinical entity presenting with swelling of the facial and/or oral tissues in association with histologic evidence of noncaseating granulomatous inflammation. Exclusion of other entities like sarcoidosis, mycobacterial infections, foreign body reactions and biopsy helps to establish a correct diagnosis. Here with reporting a case of lip swelling in 35-year old female along with palatal lesion, which was treated lucratively with steroids.

A biocatalytic approach has been developed to synthesize conducting polyaniline (PANI) nanoparticles. The method involves the formation of nanocomposites of PANI and poly(acrylic acid) (PAA) by polymerizing aniline (AN)-camphorsulfonic acid (CSA) macromonomer (AN/CSA) using a biocatalyst in the presence of template PAA. The second step involves the separation of PANI polymers from PAA and CSA in the nanocomposites. The formation of PANI nanoparticles by this two-step approach is studied by transmission electron microscopy (TEM). High-resolution solution 13C NMR and UV/visible spectroscopic techniques have been used to characterize the formation of conducting PANI chains by the enzymatic method.

Topochemical solid state polymerization is a method of obtaining fully crystalline macromolecules. Herein, approaches to conjugated polymers via new solid state polymerizations and the properties of materials, especially polydiacetylenes(PDA), obtained via solid state polymerization are discussed. Our attempts to polymerize cyanoalkynes and to define the thermal reaction product of a dicyanodiazepine are presented. Certain PDA exhibit absorption, likely charge‐transfer, at energies below the exciton. Nanocrystals of PDA‐DCH react with liquid bromine to give the mixed polyacetylene PDA‐DCHBr6whose visible spectrum exhibits structure not observed in spectra of bulk crystals of PDA‐DCHBr6. The thermochromic PDA of the dialkylurethanes of 5,7‐dodecadiyn‐1,12‐diol were studied by variable temperature solid state 13C nmr. The upfield shift of the acetylene carbons as the temperature is raised above that of the thermochromic phase transition indicates the role of mechanical strains in achieving thermochromism.

The spectral features in the solid state13C CP/MAS NMR of poly (1,1,6,6-tetraphenylhexadiyn diamine) (poly(THD)) are compared with X-ray diffraction. The NMR data suggests that acetylenic carbons are nonequivalent in the unit cell resulting in two resonances. On the other hand, a single acetylenic carbon resonance was observed for poly (1,6-di-N-carbozolyl-2,4-hexadiyne) (poly(DCH)). The orientation of side groups in the crystal structures of poly(DCH) and poly(THD) are responsible for equivalence and nonequivalence of acetylenic carbons. The structural changes due to thermochromic transitions are monitored by variable temperature solid state NMR. The solid state VT NMR data suggest that the backbone and side chain conformations of blue phase and red phases of poly(bis-n-propyl urethane of 5,7-dodecadin-1,12-diol) (poly(PUDO)) are distinctly different. For the first time, we present a solid state NMR spectrum showing the presence of both the blue and red phases of this polymer at the thermochromic transition temperature (ca. 115–125°C).

One- and two-dimensional NMR experiments are used to study substituted piperidine derivatives in both free base and salt form. The investigation of 1-methyl-2-piperidine methanol has resulted in stereostructural elucidation of this compound in the salt form.

In vivo uptake and disposition of [14C]mirex by CD1 mouse liver subcellular fractions and cells of different nuclear ploidy were examined following single or multiple doses of mirex injected intraperitoneally. Significant amounts of mirex were rapidly taken up by liver (21-29%), suggesting that liver is one of the primary sites of accumulation of the chemical. Among subcellular fractions, mirex was predominantly distributed in mitochondria and microsomes in the irreversibly bound form (about 20%), although its levels fluctuated considerably with time. Mirex was completely dissociated with trichloroacetic acid treatment from both nuclear and plasma membrane fractions, although the total uptake by these fractions was markedly high. The time course of uptake and concentration-dependent disposition of mirex revealed that polyploid hepatocytes selectively accumulated higher amounts of the chemical (two to three times) compared to diploid hepatocytes. The increased affinity of polyploid cells to mirex may indicate a greater susceptibility of this cell type to the chemical insult and also may suggest a possible early involvement of polyploids in the tumorigenic process in rodent livers.

The usefulness of the 2D-NMR techniques in the structure determination of the oligo ε-caprolactone ethyl glucopyranoside (oilgo(ε-CL) EGP) conjugate, synthesized by a lipase-catalyzed regioselective reaction, is described. Data from a 13C–13C COSY NMR spectrum of the ethyl glucopyranoside is used for complete and unambiguous assignments of the carbon resonances in the 13C NMR spectrum of the anomeric mixture of EGP. A comparison of the DEPT-135 spectrum of the product oilgo(ε-CL) EGP conjugate with that of the starting material, ethyl glucopyranoside (EGP), led to the conclusion that the lipase-catalyzed ring-opening of ε-CL initiated by a multifunctional initiator, EGP, proceeded in a regioselective fashion. Also, a detailed analysis of the NMR data has allowed determination of the site for lipase-catalyzed ring-opening polymerization of ε-CL. Our study suggests that among the possible four initiation sites in EGP only the hydroxyl group on carbon C-6 took part in the initiation process.

The enantiomer separation and the spectral simplification of overlapped resonances in a high-resolution 1H NMR spectrum of a model compound have been successfully accomplished with the use of paramagnetic shift reagent. Both 1H and 13C NMR have been applied to determine the composition of a mixture containing optically active enantiomers of (+/-)-2,2-dimethyl-1-phenyl-1-propanol.

In this report, we describe the use of in situ NMR spectroscopy to elucidate the mechanism of horseradish peroxidase-catalyzed oxidative free-radical coupling of phenols. We demonstrate the potential of the technique for the polymerization of 8-hydroxyquinoline-5-sulfonate (HQS). Based on the structural changes, we establish the involvement of ortho- and para-position protons (to the hydroxyl group) in the oxidative free-radical coupling polymerization with their relative preferences. For example, in HQS, we establish that the positions 2, 4, and 7 are involved in the chemical bonding with the order of preference being 7 ≥ 2 > 4. Analyses of ¹³C-NMR data suggest the formation of C—C- and C—O—C-type coupling bonds during enzymatic polymerization. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 1257–1264, 1998

The structural and morphological changes occurring in high-density polyethylene when exposed to gamma-radiation have been investigated by high-resolution solid state 13C NMR. NMR measurements are used to study the effect of gamma-radiation on crystalline and amorphous components. In addition, resonance peaks due to direct cross-links have been detected. The changes in main chain unsaturation are also studied.

There are several techniques and methods used to quantify the presence of low-level impurities in pharmaceutical compounds. At present it is a difficult task to determine their molecular structure unless the impurity is isolated from the pharmaceutical compound. A procedure, based on crystallization and nuclear magnetic resonance (NMR) analysis, is described for determining the molecular structure and concentration of an impurity in the presence of pharmaceutical compound, even though that impurity has not been isolated. Slow crystallization is done in order to enrich the impurity concentration to usable levels in either the solution or in some extracted powder or crystallites. High-resolution one- and two-dimensional NMR analysis of the original and enriched materials may then allow determination of the impurity's structure and its concentration in the original sample. A specific example illustrating the technique is described.

This article discusses floc formation using a computer simulation model by random conjunction of primary particles. The model flocs were generated by the successive addition to the growing floc in a random manner of primary particles, taken as spheres of unit radius. The article discusses the process, which was repeated until a floc containing the selected number of primary particles was formed. From the form of the model, it was expected that the flocs would approximate spherical symmetry; this was realized by the fact that the center of gravity of the 201‐particle flocs was never more than 1 to 1.5 particle radii from the origin. Several flocs varying in content from 101 to 401 primary particles were generated with this model. The characteristics of these flocs were then examined, and the findings generalized in terms of the floc size r (radius) and the volume fraction of solids pcfor a floc containing n primary particles.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

For Abstract see ChemInform Abstract in Full Text.

Cluster promotion programme launched during XI Five Year Plan period has been the flagship programme of Central Silk Board. The article showcases the impact of CPP programme on the qualitative aspects of bivoltine sericulture in Karnataka. [ABSTRACT FROM AUTHOR]