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Cyclodextrin-modified electrokinetic chromatography (CD-EKC) was investigated for the separation of 12 monomethylbenz[a]anthracene (MBA) isomers. Combined use of a polymeric surfactant, poly(sodium 10-undecenyl sulfate) (poly-SUS), with various types of neutral cyclodextrins (CDs) [beta-CD, gamma-CD, dimethyl-beta-CD (DM-beta-CD), trimethyl-beta-CD (TM-beta-CD) and hydroxypropyl-beta-CD (HP-beta-CD)] were successful in CD-EKC separation of the MBA isomers. Baseline resolution of 10 of the 12 isomers, except for 9-MBA and 2-MBA, was achieved with gamma-CD at pH 9.75. The beta-CD, gamma-CD, and beta-CD derivatives (DM-beta-CD, TM-beta-CD, HP-beta-CD) were found to have different resolution and selectivity. Additionally, the tR/t0 values of isomers were found to be dependent on the type and concentration of the CD additives. In general, tR/t0 values of MBA isomers decrease with an increase in the concentration of beta-CD derivatives, whereas the reversed was true when the concentrations of native beta-CD and gamma-CD were varied. The combination of 5 mM gamma-CD, 0.5% (w/v) poly-SUS, 35% (v/v) acetonitrile at a pH of 9.75 provided the best selectivity and resolution of the MBA isomers with a separation time of 110 min. However, the use of 30 mM DM-beta-CD under similar EKC conditions resulted in much faster separation (ca. 16 min) of 10 MBA isomers.

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OBJECTIVE: To evaluate the possible protective effect of verapamil (a calcium channel blocking agent) against the traumatizing effects of high-energy shockwaves (HESW) and new stone formation, as indicated by crystal deposition in the renal parenchyma, an experimental study was performed in rabbits. METHODS: A total of 65 rabbits were included. During severe hyperoxaluria induced by continuous ethylene glycol (EG) (0.75%) administration, animals in the first group (N = 15) received EG only, and animals in the second group underwent administration of 500 to 1500 shockwaves, animals in the third group (N = 15) received verapamil (0.1 mg/kg) for 3 days prior to HESW application, a control group (N = 15) received various numbers (500 to 1500) of shockwaves alone. Sham-treated animals (N = 5) constituted the last group in our study. Three months after shockwave application, tissue sections obtained from treated and untreated kidneys were evaluated histopathologically under light microscopy and transmission electron microscopy (TEM) for the presence and degree of crystal deposition in the cortical parenchymal region subjected to HESW. RESULTS: Whereas crystal deposition was evident in the intercellular region and intratubular parts of the parenchyma in animals receiving EG and HESW, especially in those receiving relatively higher numbers of shockwaves), animals receiving verapamil demonstrated limited or no crystal formation. No significant crystal deposition could be noted in specimens from animals undergoing either EG or SWL alone, and sham-treated animals demonstrated no significant alteration, as expected. CONCLUSION: Using this model, the traumatic effects of HESW could be evaluated as a factor in new stone formation after SWL. Verapamil has been found to be protective against crystal deposition.

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A method for the separation of twelve monomethyl-substituted benz[a]anthracene isomers using poly-(sodium undecylenic sulfate) (poly-SUS) surfactant by means of electrokinetic capillary chromatography (EKC) is described. Several parameters such as concentration of acetonitrile (ACN), pH, as well as applied voltage were studied to optimize the EKC separation. ACN at a concentration of 35% v/v, 12.5 mM phosphate-borate buffer, 30 kV with 0.5% w/v poly-SUS at a pH of 9.5 provided a resolution of a mixture of nine out of twelve methylbenz[a]anthracene (MBA) isomers in 50 min. The results of this study suggest that molecular length of MBA rather than length-to-breath ratio plays an important role in the elution order of some isomers.

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A double alkyl chain di(2-ethylhexyl)phosphate (DEHP) is introduced as a potential anionic micellar pseudophase for a wide range of benzene derivatives and/or polycyclic aromatic hydrocarbons (PAHs). Several parameters such as concentration of phosphated surfactant, type and concentration of organic solvents (acetonitrile, isopropanol, and methanol), as well as capillary electrophoresis separation voltage were optimized to enhance resolution, efficiency and selectivity as well as to maximize peak capacities. The migration times and selectivity order for a number of PAHs differ significantly, depending on the type of organic solvent added to the DEHP surfactant. Acetonitrile at a concentration of 30% v/v in combination with 100 mM DEHP gave optimum separation for a mixture of 21 benzene derivatives and PAHs in under 16 min.

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To evaluate the possible traumatizing effect of high-energy shockwaves (HESW) on new stone formation as indicated by crystal deposition in the renal parenchyma, we performed an experimental study in 50 rabbits. During severe oxaluria induced by continuous ethylene glycol (0.75%) administration, animals in the first group (N = 15) received 500 to 1500 shockwaves. Animals in the second group (N = 15) underwent no specific therapy apart from ethylene glycol administration. In a third group of animals (N = 15), only shockwave administration was applied. Sham group animals constituted the last group in our study (N = 5). Three months after shockwave application, tissue sections obtained from treated and untreated kidneys were evaluated histopathologically under light and transmission electron microscopy (TEM) for the presence and degree of crystal deposition in the cortical parenchymal region subjected to HESW. Crystal deposition was evident in the intercellular region and intratubular parts of the parenchyma in animals subjected to HESW application, especially in those receiving relatively high (1000 or 1500) numbers of shockwaves. On the other hand, no crystal formation and deposition was detectable in animals undergoing only ethylene glycol therapy or shockwave administration alone. Sham group animals demonstrated no significant renal histopathology. The traumatic effects of HESW should be evaluated as a factor in new stone formation after SWL.

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The resolution of cerebral vasospasm and protection of endothelial damage by Iloprost was evaluated with multicisternal injections. Sixteen adult mongrel dogs (18-20 kg) were assigned to one of three experimental groups. All animals received a total amount of 15 ml fresh unheparinized arterial blood via three injections into the cisterna magna. Selective vertebral angiography was performed on day 0 and subsequently blood injections were performed on the 2nd and 3rd days after the first injection. On the 7th day angiography was reperformed to determine the chronic vasospasm. The first group (5 dogs) was the control group and received intrathecal saline which was equal to the amount of saline in which Iloprost was diluted. The second group (5 dogs) did not receive any treatment until the 7th day. The third group (6 dogs) received Iloprost intrathecally (total 10 micrograms kg-1). In the first two groups angiographic vasospasm was prominent. For the second group intraarterial Iloprost was given on the 7th day in order to evaluate its acute effect. However there was no evidence of resolution of vasospasm. In the third group, resolution of vasospasm was verified on angiograms. Electron microscope studies of basilar arteries of the first two groups revealed degenerative changes of the endothelial cells which were separated from each other and the elastic lamina was irregularly arranged. In the intrathecal Iloprost-treated group there was little thickening in the elastic lamina and the endothelial cells were almost normal in structure. These results can be considered as the evidence of the prophylactic effect of Iloprost given by the intrathecal route in the prevention of chronic cerebral vasospasm.

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A study was undertaken to investigate bone regeneration in guinea pig mandibles implanted with Pyrost in comparison with artificial bone defects as controls. Bone defects were prepared in the angles of mandibles of 30 guinea pigs. The findings demonstrated that this bone substitute material stimulated bone healing, i.e. bone regeneration, in comparison with empty control cavities. Bone regeneration and new bone formation were found to be more extensive in Pyrost-implanted areas than in controls.

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Persistent retraction pockets causes erosion by adhering to ossicles and other structures of the middle ear. These are characterized by lysis of fibrous layer. Being in contact the squamous epithelium and the middle ear mucosa, it comprises the precursor mechanism of cholesteatoma. The present study discards the classical theories assuming epithelial migration through marginal or attic perforation; and demonstrates that these secondarily develop as a result of cholesteatoma. Retraction pocket specimens obtained from 10 cases of adhesive otitis media were examined with light and transmission electron microscopy and the presence of papillary ingrowth of the squamous epithelium was demonstrated.

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Carrageenan is a high molecular weight sulfated polygalactose extracted from the marine algae and several biological and immunological properties. Carrageenan granuloma induced subcutaneously in guinea pigs has been widely used in connective tissue studies. Carrageenan is also commonly used as an excellent phylogistic agent for inducing experimental edema. In the present investigation carrageenan granuloma produced on the dorsum of guinea was compared with the inflammatory reaction produced in the cheek. The histopathologic investigations showed that the inflammatory reaction occurred in the buccal tissues was more powerful and the healing manifestations appeared earlier and continued more rapidly in the cheek.

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An ultrastructural investigation was made to study the tissue changes occurring under complete dentures. Biopsy from 45 patient specimens were obtained from lesions of hard palate mucosa. Narrow intercellular space with less distinct bridges, loosely knit arrangement of tonofilaments, prominent endoplasmic reticulum, and vacuolar conformation of mitochondria were observed in the cells of epithelium. The underlying connective tissue was characterized by a preponderance of newly formed collagen fibers and numerous fibroblasts. Macrophages were located in the lamina propria and perivascular regions. Lymphocytes, neutrophils, and plasma cells were seen in moderate numbers. These cells, when present in clusters, should be considered as a component of the defense system.

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