Spacer Acquisition Rates Determine the Immunological Diversity of the Type II CRISPR-Cas Immune Response

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The antimetastatic effect of macrophages restored by indomethacin: concomitant tumor immunity model

The role of macrophages acting as immunologic antitumor effectors and promoters of tumor growth are poorly understood as yet. We investigated the role of macrophage in model of concomitant immunity (CI), a phenomenon of secondary tumor rejection during the primary tumor growth. It has been shown that the period of CI weakening can coincide with appearance of tumor metastases. We used mammary carcinoma (MC) artificial lung metastases to evaluate the influence of macrophages from various period of CI on the development of metastases in mice. Our results indicated that macrophages are responsible for the late period of CI weakening and suppression. To investigate weather prostaglandins can mediate suppressive effect of macrophages we used experiments with indomethacin and we found that inhibition of prostaglandin E2 synthesis by indomethacin restored antimetastatic effect of concomitant immune macrophages.     

Human Y‐chromosome short tandem repeats: A tale of acculturation and migrations as mechanisms for the diffusion of agriculture in the Balkan Peninsula

Southeastern Europe and, particularly, the Balkan Peninsula are especially useful when studying the mechanisms responsible for generating the current distribution of Paleolithic and Neolithic genetic signals observed throughout Europe. In this study, 404 individuals from Montenegro and 179 individuals from Serbia were typed for 17 Y‐STR loci and compared across 9 Y‐STR loci to geographically targeted previously published collections to ascertain the phylogenetic relationships of populations within the Balkan Peninsula and beyond. We aim to provide information on whether groups in the region represent an amalgamation of Paleolithic and Neolithic genetic substrata, or whether acculturation has played a critical role in the spread of agriculture. We have found genetic markers of Middle Eastern, south Asian and European descent in the area, however, admixture analyses indicate that over 80% of the Balkan gene pool is of European descent. Altogether, our data support the view that the diffusion of agriculture into the Balkan region was mostly a cultural phenomenon although some genetic infiltration from Africa, the Levant, the Caucasus, and the Near East has occurred. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc.     

Hierarchical structure of cascade of primary and secondary periodicities in Fourier power spectrum of alphoid higher order repeats

Background  

Identification of approximate tandem repeats is an important task of broad significance and still remains a challenging problem of computational genomics. Often there is no single best approach to periodicity detection and a combination of different methods may improve the prediction accuracy. Discrete Fourier transform (DFT) has been extensively used to study primary periodicities in DNA sequences. Here we investigate the application of DFT method to identify and study alphoid higher order repeats.     

Highly reactive cysteine residues are part of the substrate binding site of mammalian dipeptidyl peptidases III

Dipeptidyl peptidase III (DPP III) is a cytosolic zinc-exopeptidase involved in the intracellular protein catabolism of eukaryotes. Although inhibition by thiol reagents is a general feature of DPP III originating from various species, the function of activity important sulfhydryl groups is still inadequately understood. The present study of the reactivity of these groups was undertaken in order to clarify their biological significance.The inactivation kinetics of human and rat DPP III by sulfhydryl reagent p-hydroxy-mercuribenzoate (pHMB) was monitored by determination of the enzyme's residual activity with fluorimetric detection.Inactivation of this human enzyme exhibited pseudo-first-order kinetics, suggesting that all reactive SH-groups have equivalent reactivity, and the second-order rate constant was calculated to be 3523+/-567M(-1)min(-1). Rat DPP III was hyperreactive to pHMB and showed biphasic kinetics indicating two classes of reactive SH-groups. The second-order rate constants of 3540M(-1)s(-1) for slower reacting sulfhydryl, and 21,855M(-1)s(-1) for faster reacting sulfhydryl were obtained from slopes of linear plots of pseudo-first-order constants versus reagent concentration. Peptide substrates protected both mammalian DPPs III from inactivation by pHMB. Physiological concentrations of biological thiols and H(2)O(2) inactivated the rat DPP III. Human enzyme was resistant to H(2)O(2) attack and less affected by reduced glutathione (GSH) than the rat homologue. A significantly lower DPP III level, determined by activity measurement and Western blotting, was found in the cytosols of highly oxygenated rat tissues.These results provide kinetic evidence that cysteine residues are involved in substrate binding of mammalian DPPs III.