210Pb and 210Po Content in Air,Water, Foodstuffs,and the Human Body

Concentrations of ²¹⁰Pb and ²¹⁰Po in air, drinking water, foodstuffs, and human tissues are reported. The main route of ²¹⁰Pb and ²¹⁰Po intake in the human body is ingestion with foodstuffs. The absorption coefficient of ²¹⁰Po into the blood from the digestive tract was estimated to be 35%. The highest concentration of ²¹⁰Pb and ²¹⁰Po in the body was observed in the skeleton and hair. The body burden of humans was 773 pCi of ²¹⁰Pb and 513 pCi of ²¹⁰Po. Excretion of these radionuclides from the body in urine was 14 to 15 times less than in feces. The calculated annual radiation doses of ⁷¹⁰Po in the bone, liver, and kidneys were 2.1 to 5.0 millirad/yr, and in other soft tissues, 0.3 to 0.9 millirad/yr.     

Binding of human EPF to receptors on PMBC as a first signal of pregnancy immunomodulation

The interaction between human early pregnancy factor (EPF) anda specific receptor present on human peripheral blood mononuclearcells (PMBC) has been assessed. EPF was radio-iodiated by thelactoperoxidase method to a high specific activity, and the[¹²⁵I]EPF obtained bound in a specific and saturable mannerto the receptors on PBMC. Saturation of the binding sites occurredat 10^–9 M. There were 6600 specific binding sites percell in cells partially purified from pregnant women and fewerin those from non-pregnant women. Unlabelled EPF was capableof competing for binding sites with [¹²⁵I]EPF, while the bindingof [¹²⁵I]EPF was not inhibited by human chorionic gonadotrophin.A new assay was used that permits the culture of PBMC and thedetection of the surface IgG expression in the same microplate.With this method the influence in vitro of human EPF on lymphocyteexpression was tested. The results demonstrated a specific inhibitionof surface IgG expression of PBMC using a very low concentrationof EPF (10 pg/ml).     

Copolymers prepared on the basis of isopropenyl derivatives of o-carborane

New mono- and bifunctional isopropenyl derivatives of o-carborane were synthesized according to the Witting reaction, from the corresponding acetyl derivatives and methylenetriphenylphosphorane. The radical copolymerization with methyl methacrylate was investigated and thermal and thermomechanical characteristics of the obtained copolymers were studied. In copolymers prepared on the basis of a monofunctional carborane-containing monomer, the increase of glass transition temperature takes practically a linear course with increasing boron content. In crosslinked copolymers the presence of o-carborane fragments leads to the widening of the glass transition temperature range, predominantly at low temperatures, irrespective of the type of bifunctional monomer used.     

Genetic mapping of autosomal dominant primary open-angle glaucoma (POAG) in Sardinia

Primary open-angle glaucoma (POAG) can be subdivided into two groups according to age of onset: (1) the more prevalent middle to late-age-onset chronic open-angle glaucoma (COAG) diagnosed after age 40, and (2) the less common form, juvenile open-angle glaucoma (JOAG), which occurs between 3 years of age and early adulthood. Susceptibility to either COAG or JOAG has been found to be inherited. The discovery of several genetic markers spanning the region 1q21-q24 in genetic linkage with autosomal dominant juvenile open-angle glaucoma (adJOAG) represents a major breakthrough towards the localisation of gene(s) responsible for the disease. Linkage analysis is a powerful means of distinguishing disease loci in large families with dominant disease. However the size of the group of families may represent a crucial factor for the linkage analysis. Sardinia is an island with a relatively isolated ethnic group showing a relatively high frequency of ad JOAG and COAG (Fossarello et al., 1994) and it is genetically more homogeneous than most Western populations. Therefore it represents an ideal ethnic group to search for linkage. We identified 18 families affected by POAG in which the disease appears to be inherited as autosomic dominant trait. In all families but two, occurrence of both JOAG and COAG in the same kindred was observed. Identification of adPOAG locus was performed by linkage analysis using 9 microsatellite markers spanning the region 1q21-q24. No significant linkage was observed. Our findings provide further evidence for genetic heterogeneity in autosomal dominant primary open angle glaucoma, even in a geographic area where a relatively homogeneous genetic background exists.     

Eudragit RS100 nanosuspensions for the ophthalmic controlled delivery of ibuprofen.

Topical application of non-steroidal anti-inflammatory drugs on the eye is a common treatment used to contrast the miosis induced by surgical traumas, such as cataract extraction. With the aim of improving the availability of sodium ibuprofen (IBU) at the intraocular level, IBU-loaded polymeric nanoparticle suspensions were made from inert polymer resins (Eudragit RS100). The nanosuspensions were prepared by a modification of the quasi-emulsion solvent diffusion technique using variable formulation parameters (drug-to-polymer ratio, total drug and polymer amount, stirring speed). Nanosuspensions had mean sizes around 100 nm and a positive charge (zeta-potential of +40/+60 mV), this makes them suitable for ophthalmic applications. Stability tests (up to 24 months storage at 4 degrees C or at room temperature) or freeze-drying were carried out to optimize a suitable pharmaceutical preparation. In vitro dissolution tests indicated a controlled release profile of IBU from nanoparticles. In vivo efficacy was assessed on the rabbit eye after induction of an ocular trauma (paracentesis). An inhibition of the miotic response to the surgical trauma was achieved, comparable to a control aqueous eye-drop formulation, even though a lower concentration of free drug in the conjunctival sac was reached from the nanoparticle system. Drug levels in the aqueous humour were also higher after application of the nanosuspensions; moreover, IBU-loaded nanosuspensions did not show toxicity on ocular tissues.     

Morphological differentiation of the conjunctival goblet cells in the chick (Gallus domesticus)

Background: These is no consensus in the literature regarding the differentiation of conjunctival goblet cells in vertebrates. Method: The conjunctival epithelium of the chick was studied before and after hatching in order to demonstrate the morphological evolution of the goblet cells. The entire conjunctiva was processed for light microscopy either on semithin sections stained with toluidine blue-pironine or on traditional sections stained with Alcian blue pH 2.5-PAS. Results: It was possible to demonstrate that goblet cells underwent remarkable changes in their secretory activity. At 12 h after hatching, isolated Alcian blue-positive cells were present in the fornix. At 24 h after hatching, cells positive for both Alcian blue and PAS were scattered among epithelial cells. Two days after hatching, cells which reacted positively only to PAS were also present. Conclusion: It is suggested that the differentiation of conjunctival goblet cells occurs first in the fornix, probably due to the particular vascular environment of this region, and then spreads all over the conjunctiva.