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71.
The bactericidal activities of cattle and swine platelet microbicidal proteins (PMPs) with their comparison with human PMP were studied. Activities of PMP were tested against Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus lysodeikticus and Escherichia coli. B. subtilis and B. cereus were high susceptible to PMP at very low concentrations. Of the gram-positive cocci studied, M. lysodeikticus and S. aureus were the most, and S. epidermidis the least, susceptible. E. coli was found to be relatively resistant to the lethal action of all PMP. The findings of this study confirm that the existence of antimicrobial peptides is conserved among mammalian platelets.  相似文献   
72.
Nonsteroid antiinflammatory agents (NAIA) such as antipyrine, butadion, acetylsalicylic acid, sodium salicylate, stampyrine and 4-iodantipyrine are not interferonogenic. Still, they stimulated interferonogenic action of poly(G).poly(C) in studies on animals. Relation between the interferon-stimulating action of the NAIA and their effect on activity of prostaglandin and the influence on the immune system was suggested.  相似文献   
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Human altruism is a widespread phenomenon that puzzled evolutionary biologists since Darwin. Economic games illustrate human altruism by showing that behavior deviates from economic predictions of profit maximization. A game that most plainly shows this altruistic tendency is the Dictator Game. We hypothesized that human altruistic behavior is to some extent hardwired and that a likely candidate that may contribute to individual differences in altruistic behavior is the arginine vasopressin 1a (AVPR1a) receptor that in some mammals such as the vole has a profound impact on affiliative behaviors. In the current investigation, 203 male and female university students played an online version of the Dictator Game, for real money payoffs. All subjects and their parents were genotyped for AVPR1a RS1 and RS3 promoter-region repeat polymorphisms. Parents did not participate in online game playing. As variation in the length of a repetitive element in the vole AVPR1a promoter region is associated with differences in social behavior, we examined the relationship between RS1 and RS3 repeat length (base pairs) and allocation sums. Participants with short versions (308-325 bp) of the AVPR1a RS3 repeat allocated significantly (likelihood ratio = 14.75, P = 0.001, df = 2) fewer shekels to the 'other' than participants with long versions (327-343 bp). We also implemented a family-based association test, UNPHASED, to confirm and validate the correlation between the AVPR1a RS3 repeat and monetary allocations in the dictator game. Dictator game allocations were significantly associated with the RS3 repeat (global P value: likelihood ratio chi(2) = 11.73, df = 4, P = 0.019). The association between the AVPR1a RS3 repeat and altruism was also confirmed using two self-report scales (the Bardi-Schwartz Universalism and Benevolence Value-expressive Behavior scales). RS3 long alleles were associated with higher scores on both measures. Finally, long AVPR1a RS3 repeats were associated with higher AVPR1a human post-mortem hippocampal messenger RNA levels than short RS3 repeats (one-way analysis of variance (ANOVA): F = 15.04, P = 0.001, df = 14) suggesting a functional molecular genetic basis for the observation that participants with the long RS3 repeats allocate more money than participants with the short repeats. This is the first investigation showing that a common human polymorphism, with antecedents in lower mammals, contributes to decision making in an economic game. The finding that the same gene contributing to social bonding in lower animals also appears to operate similarly in human behavior suggests a common evolutionary mechanism.  相似文献   
75.
Infectious endocarditis can be caused by various microorganisms. Diagnostics of local infection by microbiological methods is not always effective. For that reason we performed a study aimed for direct detection of potential infectious agents by polymerase chain reaction in patients' heart valve tissue. DNA of infectious agents was revealed in 72% of heart valve tissue samples from patients with septic endocarditis; in studied samples, along with bacterial DNA, herpesviruses' DNA was detected. Obtained results confirm the presence of infection, which allows to perform specific diagnostics of infectious complications after implantation of prosthetic cardiac valves.  相似文献   
76.
Morphological and some biological specific features of nine samples of the southern form of Dolly Varden trout Salvelinus malma krascheninnikovi from water bodies of Sakhalin were studied. Comparative analysis was performed of our own estimates and estimates made by other authors of meristic characters of Sakhalin populations of Dolly Varden trout, as well as of samples from water bodies of the Kuril Islands and Western Kamchatka. Sakhalin populations of S. malma krascheninnikovi are characterized by a low level of morphological differentiation and the absence of geographic structure. No clinal latitudinal variation in sample averages was revealed in either of the nine studied meristic characters, including the number of vertebrae for populations of S. malma krascheninnikovi in the range from Bol’shoi Shantar Island to the south of Sakhalin. The cline in vertebral number from Kamchatka, along the Kuril Islands to Hokkaido, is most likely explained by specific features of distribution and introgressive hybridization at the secondary contact of populations of the northern and southern forms of Dolly Varden trout that originated from different glacial refugia and had a different vertebral number rather than by the temperature gradient.  相似文献   
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The present work deals with localization of previously unknown polymerization sites of the fibrin DD-fragment. D-dimer we obtained has a pronounced inhibitory effect on fibrin polymerization (IC50 = 0.06 M). The inhibitory effect of the D-fragment disappeared after reduction and carboxymethylation. However, polypeptide chains DD (B134-461) and DD (63-411)2 of the DD-fragment, isolated by preparative electrophoresis, displayed their inhibitory activity. For instance, the rates of fibrin protofibril lateral association were decreased twice in the presence of DD and DD chains at their molar ratios to fibrin of 0.40 and 0.15, respectively. The IC50 values for DD and DD were 0.24 and 0.10 M, respectively. Highly specific inhibition of protofibril lateral association suggests that the protofibril lateral association sites are located in B134-461 and 63-411 regions of the fibrin D-domain. Our data confirm those reported by Doolittle et al. regarding the -chain and a hypothesis about -chain of fibrin D-domain (Yang, Z., Mochalkin, I., and Doolittle, R. F. (2000) Biochemistry, 97, 14156-14161).  相似文献   
79.
Formation of palmitic acid/Ca(2+) (PA/Ca(2+)) complexes was suggested to play a key role in the non-classical permeability transition in mitochondria (NCPT), which seems to be involved in the PA-induced apoptosis of cardiomyocytes. Our previous studies of complexation of free fatty acids (FFA) with Ca(2+) showed that long-chain (C:16-C:22) saturated FFA had an affinity to Ca(2+), which was much higher than that of other FFA and lipids. The formation of FFA/Ca(2+) complexes in the black-lipid membrane (BLM) was demonstrated to induce a nonspecific ion permeability of the membrane. In the present work, we have found that binding of Ca(2+) to PA incorporated into the membrane of sulforhodamine B (SRB)-loaded liposomes results in an instant release of a part of SRB, with the quantity of SRB released depending on the concentration of PA and Ca(2+). The pH-optimum of this phenomenon, similar to that of PA/Ca(2+) complexation, is in the alkaline range. The same picture of SRB release has been revealed for stearic, but not for linoleic acid. Along with Ca(2+), some other bivalent cations (Ba(2+), Sr(2+), Mn(2+), Ni(2+), Co(2+)) also induce SRB release upon binding to PA-containing liposomes, while Mg(2+) turns out to be relatively ineffective. As revealed by fluorescence correlation spectroscopy, the apparent size of liposomes does not alter after the addition of PA, Ca(2+) or their combination. So it has been supposed that the cause of SRB release from liposomes is the formation of lipid pores. The effect of FFA/Ca(2+)-induced permeabilization of liposomal membranes has several analogies with NCPT, suggesting that both these phenomena are of similar nature.  相似文献   
80.
Affinity labeling of methyltransferase MvaI by DNA duplexes containing oxidized 2'-O-beta-D-ribofuranosylcytidine or 1-beta-D-galactopyranosyl)thymine residues was performed. Partial chemical hydrolysis of the covalently bound methylase in the conjugates with the dialdehyde-containing DNA allowed us to determine the amino acid region in the C terminus of methylase MvaI that interacts with DNA.  相似文献   
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