Altered postreceptor signal transduction of formyl-Met-Leu-Phe receptors in polymorphonuclear leukocytes of patients with non-insulin-dependent diabetes mellitus

The 5-HT1A receptor agonist (-)-(R)-2-[4-[[(3,4-dihydro-2H-1-benzopyran-2-yl)methyl]amino]butyl]-1,2 -benzisothiazol-3(2H)-one1,1-dioxide monohydrochloride (BAY x 3702) was recently shown to have pronounced neuroprotective effects in rat models of cerebral ischemia and traumatic brain injury. In the present study we investigated the neuroprotective effects of BAY x 3702 in primary cultures of hippocampal and cortical neurons. Cell death was induced by 25 nM of the apoptosis inducing agent staurosporine and analyzed 24 h later by release of lactate dehydrogenase, formation of apoptotic bodies and DNA fragmentation. A significant neuroprotection was seen after pretreatment of the affected neurons with 50 pM to 1 microM BAY x 3702. The effects of BAY x 3702 were completely blocked by the selective 5-HT1A receptor antagonist N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridinyl) cyclohexanecarboxamide trihydrochloride) (WAY-100635). These results indicate that low concentrations of BAY x 3702 protect cortical as well as hippocampal neurons from apoptotic cell death via a 5-HT1A receptor mediated pathway.     

Monoclonal antibodies detecting components of the bovine immune system in formaldehyde-fixed paraffin-embedded tissue specimens

Although the use of monoclonal antibodies in the diagnosis of fixed human material is a daily routine, the lack of suitable reagents recognizing epitopes resistant to formaldehyde fixation is an obvious limit to extending this approach to veterinary research and practice. To find reagents that retain their binding capacity to the recognized epitopes in formaldehyde-fixed samples, bovine lymphoid tissue sections were immunostained using various antigen retrieval procedures with monoclonal antibodies raised against ruminant leukocyte cell surface molecules. As a results, a set of antibodies could be established that allowed the identification of different immune cell types including all or a distinct subpopulation of B and T lymphocytes, monocytes, macrophages, granulocytes, red blood cells, and vascular endothelial cells.     

Comparison of the Efficacy of Two Novel Antitubercular Agents in Free and Liposome-Encapsulated Formulations

Tuberculosis is one of the top ten causes of death worldwide, and due to the appearance of drug-resistant strains, the development of new antituberculotic agents is a pressing challenge. Employing an in silico docking method, two coumaran (2,3-dihydrobenzofuran) derivatives—TB501 and TB515—were determined, with promising in vitro antimycobacterial activity. To enhance their effectiveness and reduce their cytotoxicity, we used liposomal drug carrier systems. Two types of small unilamellar vesicles (SUV) were prepared: multicomponent pH-sensitive stealth liposome (SUV_mixed) and monocomponent conventional liposome. The long-term stability of our vesicles was obtained by the examination of particle size distribution with dynamic light scattering. Encapsulation efficiency (EE) of the two drugs was determined from absorption spectra before and after size exclusion chromatography. Cellular uptake and cytotoxicity were determined on human MonoMac-6 cells by flow cytometry. The antitubercular effect was characterized by the enumeration of colony-forming units on Mycobacterium tuberculosis H₃₇Rv infected MonoMac-6 cultures. We found that SUV_mixed + TB515 has the best long-term stability. TB515 has much higher EE in both types of SUVs. Cellular uptake for native TB501 is extremely low, but if it is encapsulated in SUV_mixed it appreciably increases; in the case of TB515, quasi total uptake is accessible. It is concluded that SUV_mixed + TB501 seems to be the most efficacious antitubercular formulation given the presented experiments; to find the most promising antituberculotic formulation for therapy further in vivo investigations are needed.