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Aminoferrocene-based prodrugs are activated in cancer cells by reactive oxygen species (ROS). They were shown to exhibit high cytotoxicity towards a variety of cancer cell lines and primary cancer cells, but remain not toxic towards non-malignant cells. However, these prodrugs have rather high lipophilicity leading to relatively low water solubility. In particular, an n-octanol/water partition coefficient for the best aminoferrocene-based prodrug (2) was found to be 4.51±0.03. Though the approaches for decreasing lipophilicity are straightforward and include the addition of polar residues to the drug structure, these modifications also lead to dramatic decrease of cell permeability and, correspondingly, lower the activity of the drug. Therefore, a delicate balance of polar and unpolar groups should be found to reduce lipophilicity without compromising the useful drug properties. In this study we optimized an N-alkyl substituent, which is a key element responsible for the stabilization of the aminoferrocene drug released in cancer cells from prodrug 2. We found that an N-propargyl residue is an optimal replacement for the N-benzyl fragment. In particular, such a substitution (prodrug 7a) leads to reduction of prodrug lipophilicity down to logP=3.78±0.05, improvement of its water solubility, decrease of its propensity towards aggregation and dramatic increase of its ROS-generating properties. Finally, we demonstrated that the optimized prodrug strongly suppresses growth of Guerin's carcinoma (T8) in vivo at the dose of 30mg/kg.

Gephyrin is a major postsynaptic scaffolding protein at GABAergic and glycinergic inhibitory synapses. Gephyrin-deficient (geph(-/-)) mice die after birth due to disinhibition of motor and sensory pathways resulting from a lack of postsynaptic glycine receptor and GABA(A) receptor clusters. Here, immunoelectron and confocal microscopy revealed that postsynaptic membrane specializations are formed in the absence of gephyrin. First, in brainstem sections obtained from newborn geph(-/-) mice inhibitory nerve terminals identified by immunogold labeling of either the vesicular inhibitory amino acid transporter (VIAAT) or GABA were found to be apposed to postsynaptic membrane areas decorated by electron-dense material. Second, neuroligin-2, a membrane protein of inhibitory postsynapses, was clustered beneath glutamate decarboxylase 65 (GAD-65) positive nerve terminals in geph(-/-) hippocampal cultures. These results indicate that proteins other than gephyrin define the ultrastructure of inhibitory postsynaptic membrane specializations.

We investigated immunohistochemically the cellular localization of multifunctional type II Ca 2+ /calmodulin-dependent protein kinase in the rat basal ganglia and intrastriatal grafts derived from fetal striatal primordia, in comparison with that of calcineurin, a reliable marker for striatal medium-sized spinous neurons. The type II Ca 2+ /calmodulin-dependent protein kinase-positive neurons were of medium size, with a mean diameter of 16.1 ± 1.8 μm ( average±S.D ., n = 72 , range 13.6–18.3 μm) and comprised approximately 70% of the total neuronal population in the striatum. Light microscopy showed that the type II Ca 2+ /calmodulin-dependent protein kinase-positive cells had round, triangular or polygonal cell bodies with relatively little cytoplasm. Analysis of serial sections showed that type II Ca 2+ /calmodulin-dependent protein kinase and calcineurin immunoreactivities were co-localized in the striatal neurons examined with a similar distribution pattern. Type II Ca 2+ /calmodulin-dependent protein kinase-positive cells were always immunoreactive for calcineurin and cells negative for type II Ca 2+ /calmodulin-dependent protein kinase showed no apparent calcineurin immunoreactivity. Type II Ca 2+ /calmodulin-dependent protein kinase-positive nerve fibers in the globus pallidus and substantia nigra almost disappeared following striatal ischemie injury produced by transient middle cerebral artery occlusion and cerebral hemitransection, respectively, suggesting that these immunopositive fibers were striatal projections. Thus, most type II Ca 2+ /calmodulin-dependent protein kinase-positive neurons in the rat striatum are considered to be of the medium-sized spinous type. Type II Ca 2+ /calmodulin-dependent protein kinase or calcineurin immunoreactivity was also observed in a large number of neurons in transplants derived from fetal striatal primordia grafted into striatal ischemie lesions. In addition, type II Ca 2+ /calmodulin-dependent protein kinase- or calcineurin-immunoreactive nerve fibers appeared in the deafferented globus pallidus of the host rats, suggesting that the striatopallidal pathway was reformed by striatal projection neurons of the transplants. This finding may also indicate that Ca 2+ /calmodulin-regulated enzymes are useful for tracing striatal projection fibers as endogenous marker proteins.

Developing countries have lost billions of dollars during the last decade due to the deterioration of their roads. The macroeconomic losses caused by the lack of adequate road maintenance could be avoided by improving maintenance practices. This paper describes a method to analyze and improve present road maintenance practices in developing countries, referring to a recently conducted study in Nepal. Road maintenance is understood to be not just a technical problem, but rather a complex system with various elements. Therefore, road maintenance problems have to be tackled with different approaches on different levels. Proceeding from the existing system deficiencies, or “problem areas,” and on the basis of a hierarchy of instrumental objectives, the development of measures and projects suited to improve road maintenance practices is described. The application of a standardized evaluation scheme can support governments and development organizations in choosing promising measures in this field.