Preparation of anti-inhibitor serum and its effect on the multiplication of influenza virus

Antiserum был подготовлен противингибитор вируса haemagglutination (IVH)одна из эмбриона chorioallantoic мембр анныепутем иммун изации морских св инокЭто анти-инги битора в сыворотке заблокирован ингибирование IVH из chorioallantoicмембран в haemagglutination испытанияно ника кого влияния на ре цепторы эритроци товСыворотке кро] ви не влияет рост chorioallantoic мембраны клет ок инет нейтрализ овать воздействи е на вирус гриппа Она снизилась спо собность chorioallantoic мембр ан для adsorb вируса гри ппа, а также степен ь размножения вир усав такого рода тканиАвторы хоте ли бы поблагодари ть г-н Г. Ruttkay-Ne -палубе и для проведения эле ктрофореза меру ния.     

Transposition, amplification, and divergence in the origin of the DNF15 loci, a polymorphic repetitive sequence family on chromosomes 1 and 3

The loci DNF15S1 and DNF15S2 are members of a small repetitive sequence family at discrete chromosomal locations, namely, 1p36 and 3p21, respectively. Studies of the structure, arrangement, and interrelations of the family suggest that the single copy on chromosome 3 is the original member and that this gave rise to the several members on chromosome 1 by transposition, partial duplication, and amplification. Several restriction fragment length polymorphisms have been discovered at the DNF15S1 locus and these have been assigned to the different subfamilies of the repeat at this locus. The existence of these RFLPs, and the nonallelic restriction site variation also found in this sequence family, suggests that transposition and amplification occurred as discrete events. We sequenced across the ancient junction between chromosomes 1 and 3 and noted features which might explain the mechanics of the transposition and amplification events.     

Priming of the respiratory burst in human eosinophils is accompanied by changes in signal transduction

Addition of platelet-activating factor (PAF) to human eosinophils leads to the modulation of eosinophil responses. The respiratory burst, induced by opsonized particles, consists of an initiation and a propagation phase and is greatly enhanced ("primed") after pretreatment with PAF. This priming event induces the following changes in signal transduction between the opsonin receptors (in particular the CR3 receptor) and activation of the respiratory burst: 1) an enhanced activation of protein kinase C (PK-C): the initiation of the respiratory burst in untreated eosinophils is not sensitive to PK-C inhibition (via staurosporine) and is not accompanied by accumulation of diglycerides and changes in [Ca2+]i. After pretreatment with PAF, the initiation of the response is partly sensitive to inhibition of PK-C (via staurosporine) and is accompanied by accumulation of diglycerides and a fast and sustained increase in [Ca2+]i; and 2) an enhancement of a PK-C-independent initiation of the respiratory burst. The propagation phase in both primed and unprimed cells is sensitive for inhibition by staurosporine. Our results indicate that in eosinophils the phospholipase(s) responsible for the accumulation of the diglycerides and changes in [Ca2+]i during the initiation phase of the serum-treated zymosan response seem(s) to become associated with the signal transduction route only after priming with PAF. This results in the occurrence of two signal transduction routes that can act independently of each other.     

Isolation of Glutamyltaurine from Bovine Brains and Proof of Its γ-Linkage by the B/E Linked Scan SIMS Technique

We isolated a glutamyltaurine from bovine brains and determined its structure as gamma-glutamyltaurine (gamma-Glu-Tau; glutaurine) by use of a new mass spectrometric technique [B/E linked scan sputtered ion mass spectrometry (SIMS)], which we have recently shown to be useful for distinguishing the gamma- from the alpha-isomer of glutamyl-dipeptides. Neither the alpha-isomer of glutamyltaurine nor any aspartyltaurines could be detected in bovine brain.     

Multiple T and B cell epitopes in the S1 subunit ("A"-monomer) of the pertussis toxin molecule

The immunogenicity and reactogenicity of Bordetella pertussis vaccine are mediated in part by the S1 subunit of pertussis toxin (PT). To identify the immune epitopes in the S1 subunit of PT, synthetic peptides were prepared and tested for their capacity to induce antibodies in mice with different MHC genotypes. In BALB/c mice, peptides corresponding to sequences 1-17, 70-82 and 189-199 generate T cell proliferative responses, induce the production of antibodies capable of neutralization of the toxin in the Chinese hamster ovary-cell assay, and protect mice from a shock-like syndrome caused by alternate injections of BSA and PT. Protection and neutralization correlated with the ability of these peptides to elicit high anti-PT titers. Different B cell epitopes were detected in other inbred mouse strains. The antibody reactivity against synthetic peptides from two infants vaccinated with pertussis vaccine was tested. These infants had antibodies reactive to a variety of epitopes in the S1 subunit, including peptides 1-17, 70-82, 99-112, 135-145, and 189-199. Thus, it appears that there are multiple T and B cell epitopes in the S1 subunit of PT.     

Dual mechanisms in priming of the chemoattractant-induced respiratory burst in human granulocytes. A Ca2+-dependent and a Ca2+-independent route

After interaction with so-called priming agents, the respiratory burst in human granulocytes does not become activated, but is enhanced upon subsequent stimulation with the chemoattractant FMLP. Investigating the mechanism of the priming reaction, we found that a transient rise in the cytosolic free calcium concentration [( Ca2+]i) suffices to irreversibly prime human granulocytes. Thus, platelet-activating factor (PAF) induced a transient increase in [Ca2+]i and primed the cells to an enhanced respiratory burst upon subsequent interaction with FMLP. Artificially, the transient rise in [Ca2+]i was mimicked by addition and subsequent removal of the Ca2+ ionophore ionomycin; this treatment too, primed the respiratory burst of the granulocytes. The priming induced by ionomycin was completely abolished when [Ca2+]i changes were buffered during exposure of the cells to the ionophore. The priming induced by PAF was only partially inhibited under [Ca2+]i-buffering conditions during priming, indicating that multiple pathways exist in the priming of granulocytes by PAF.     

The effect of dehydration on the functional activity of the interrenal gland in adenohypophysectomized Rana catesbeiana frogs. A preliminary report

A significant increase of the content of corticosterone in the blood collected from intravenous cannula or by intracardiac punction has been detected using radioimmunoassay in non-operated and adenohypophysectomized frogs Rana catesbeiana subjected to dehydration in 6.2% mannitol solution during 24 hours. The osmolality of the blood plasma of these animals also increases although less significantly than the growth of plasma corticosterone content. There is a tendency to substantial increase of plasma arginine-vasotocin level prior to the growth of corticosterone level, already after 6 hours of dehydration. Based on the present results and literature data, it is suggested that in adenohypophysectomized frogs lacking endogenous ACTH just the increase of blood arginine-vasotocin level results in a substantial activation of corticosteroid-producing cells of the interrenal gland and in the growth of plasma content of corticosterone.     

The effects of xylazine and alpha-adrenoreceptor antagonists on bovine uterine contractility in vitro

The effects of alpha-adrenoreceptor antagonists prazosin (alpha-1), yohimbine (alpha-2), and idazoxan (alpha-2) on xylazine-induced bovine uterine contractility were tested in vitro. Uterine strips from proestrous/estrous and diestrous cows were mounted in tissue baths containing Tyrode's solution. Changes in uterine contractility were measured by strain gauge. The following results were observed: 1) Xylazine increased uterine contractility in a dose dependent manner (cumulative concentrations: 10(-8), 3x10(-8), 10(-7), 3x10(-7) and 10(-6)M). 2) Idazoxan (10(-8), 10(-7) and 10(-6)M) and yohimbine (10(-6), 10(-5) and 10(-4)M) antagonized uterine contractility induced by xylazine in a dose-dependent manner. Idazoxan was approximately 50 to 100 times more potent than yohimbine. 3) Prazosin (10(-5)M) did not alter the effect of xylazine on uterine contractility. These results suggested that xylazine-induced uterine contractility in the cyclic cow is directly mediated by myometrial alpha-2 adrenoreceptors.