Ochratoxin A in pig blood: method of analysis and use as a tool for feed studies

A procedure is presented for screening the quality of feed in respect to ochratoxin A contamination based upon the analysis of ochratoxin A in pig blood. Representative samples from large feed lots may be obtained by using pigs as in vivo sample collectors which enrich the toxin and forms homogeneous samples in the blood. The spectrofluorometric procedure for ochratoxin A analysis (K. Hult and S. Gatenbeck, J. Assoc. Off. Anal. Chem. 59:128-129, 1976) has been adapted to pig blood and has been simplified to involve only three extraction steps. A volume of 2.5 ml of blood or plasma is needed, and the detection limit is 2 ng of ochratoxin A per ml. The disappearance of ochratoxin A from pig blood as a function of time has been studied. A feeding experiment with ochratoxin A has been performed, and the time course of the concentration of ochratoxin A in blood has been followed during the experiment.     

Ochratoxin A in pig blood: method of analysis and use as a tool for feed studies.

A procedure is presented for screening the quality of feed in respect to ochratoxin A contamination based upon the analysis of ochratoxin A in pig blood. Representative samples from large feed lots may be obtained by using pigs as in vivo sample collectors which enrich the toxin and forms homogeneous samples in the blood. The spectrofluorometric procedure for ochratoxin A analysis (K. Hult and S. Gatenbeck, J. Assoc. Off. Anal. Chem. 59:128-129, 1976) has been adapted to pig blood and has been simplified to involve only three extraction steps. A volume of 2.5 ml of blood or plasma is needed, and the detection limit is 2 ng of ochratoxin A per ml. The disappearance of ochratoxin A from pig blood as a function of time has been studied. A feeding experiment with ochratoxin A has been performed, and the time course of the concentration of ochratoxin A in blood has been followed during the experiment.     

Analysis of HGPRT- CRM+ human lymphoblast mutants.

Three 6-thioguanine-resistant mutants of the human diploid lymphoblast line MGL-8 were studied. The inactivation by heat of both HGPRT activity and antigenicity of the HGPRT immunologically cross-reacting material of the A30 mutant cells were not protected by PRPP, indicating that the HGPRT in A30 cells has an altered PRPP binding site, leading to lack of stabilization and rapid degradation of the enzyme. Two dimensional separations of the immunoprecipitates from extracts of the parental and mutant cell lines showed that the A35 mutant CRM has a more acidic isoelectric pH, while the A30 CRM has a more basic isoelectric pH and that the A30 protein has a faster rate of degradation than the wild-type HGPRT. The A30 CRM also has a smaller molecular size than the wild-type enzyme.     

Saponin Adjuvants. IV. Evaluation of The Adjuvant Quil a in the Vaccination of Cattle Against Foot-And-Mouth Disease

The saponin adjuvant Quil A has been investigated in the vaccination of cattle against foot-and-mouth disease. Using a Frenkel type vaccine a dose-response relationship has been established between Quil A and neutralizing antibody titres. Ten ml of vaccine was combined with 0, 50, 200, 800, and 3200 µg of Quil A. The combinations were each injected into 4 animals. The local reaction on the site of injection produced by injection of the vaccine alone and in combination with different doses of Quil A has been estimated. On this basis a therapeutical dose at 1 mg of Quil A has been estimated to combine maximum adjuvant effect with a minimum of adverse reactions. This dose has been tested in the vaccination of cattle with FMD vaccines derived from BHK suspension cell virus of type O and A respectively. The vaccines were tested in 10 ml and 5 ml doses with or without Quil A, and each in 4 animals. It is concluded that Quil A is a valuable adjuvant for use in the induction of neutralizing antibodies against foot-and-mouth disease in cattle.     

Bacteria of the genus Acinetobacter. Their systematics and ecological analysis

The content of A. lwoffi and A. calcoaceticus in water and sewage has been determined. A considerable prevalence of A. lwoffi in both objects has been revealed. The most definite results have been obtained with the use of selective media: ethanol-ammonium medium and Baumann's modified nitrate-acetate medium. The seasonal dynamics of both species in water has been determined, the peak being observed in June and the decrease (and with A. calcoaceticus even disappearance), in August.     

Surface properties of monomolecular films of oxidized and reduced cytochrome c and f.

The surface properties of monomolecular films of oxidized and reduced cytochromes f and c were measured at an air-water interface. Area/molecular (A) and surface potential (deltaV) for oxidized and reduced forms of the cytochromes were measured as a function of pH. Oxidized cyt f has a maximum for both A and deltaV at pH 7.5. At a surface pressure of 6 dyn/cm the maximum A equals 2600 plus or minus 50 A2 and the maximum deltaV equals 200 plus or minus 10 mV. Reduced cyt f as a function of pH has a minimum value for both A (2200 A2) and deltaV (95 mV). Oxidized cyt c as a function of pH has minima for A (140 A2) and deltaV (188 mV) at pH 7.0 and 7.3, respectively. On the other hand, reduced cyt has maximum values for A (220 A2) and deltaV (260 mV) at pH 7.0 and 7.3, respectively.     

Crystallization and preliminary X-ray crystallographic studies on Type III antifreeze protein.

Type III antifreeze protein, more specifically the recombinant QAE-Sephadex-binding isoform, has been crystallized in 50-55% saturated ammonium sulfate, 0.1 M sodium acetate, pH 4.0-4.5. The resultant crystals belong to the orthorhombic space group P212121 with a = 32.60 A, b = 39.00 A, and c = 46.57 A and diffract to at least 1.7 A. A set of 1.7-A native data has been collected, with completeness 93.4% and Rsym of 0.069. Initial screening for heavy-atom derivatives has yielded a Pt-bound derivative.     

Structural and dynamic properties of a fluorouracil-adenine base pair in DNA studied by proton NMR

An oligodeoxynucleotide duplex containing the chemotherapeutic agent 5-fluorouracil (FU) has been constructed by solid phase phosphotriester synthesis and has been studied in solution by proton NMR. In this study, we provide the first structural characterization of a DNA complex containing a FU.A base pair. It has been determined that the 7-mer duplex containing a central FU.A base pair adopts a normal right-handed configuration and the A residue in the FU.A pair is oriented in the normal anticonfiguration giving a Watson-Crick base pair. The significant difference between T.A and FU.A base pairs is dynamic, not structural: the FU.A base pair opens faster than normal base pairs in the oligonucleotide studied. We provide evidence that the FU.A base pair has a significantly enhanced opening rate resulting form decreased stacking of the 5-fluorouracil residue and not from the enhanced acidity of the 5'-fluorouracil imino proton.     

Phylogeny and distribution of the phoracanthine genus Atesta (Coleoptera: Cerambycidae) from Australia

The phylogeny of the phoracanthine genus Atesta (thirty-four species) is analysed using cladistic methods. The monophyly of Atesta is confirmed. Three major monophyletic species groups are recognized: (1) the thorntoni -group including twelve species: A.thorntoni, A.balteata, A.latifasciata, A.mediana, A.patula, A.newi, A.angasi, A.bifasciata, A.besti, A.ciliata, A.paratasmanica and A.tasmanica ; (2) the sisyrioides -group consisting of seventeen species: A.ibidionoides, A.carteri, A.longoelytrata, A.pubescens, A.stigmosa, A.sita, A.vittata, A.sparsa, A.minuta, A.tropicalis, A.unifasciata, A.sisyrioides, A.nigrihumerus, A.apicalis, A.brittoni, A.antennalis and A.brooksi , and (3) the houstoni -group containing five species: A.mapida, A.houstoni, A.tripartita, A.dixoni and A.centroaustralica. The distribution patterns of Atesta are described and discussed. Five distinct areas of endemism are found for Atesta: the Torresian, Timorian, Kosciuskan, Western and Eyrean Subregions. The Torresian Subregion has nine species, three of which are endemic to the subregion; the Timorian has four species, two of which are endemic; the Kosciuskan has twenty-three species, sixteen of which are endemic, the Western has five species, four of which are endemic, and the Eyrean has three species, one of which is endemic. Two kinds of distribution patterns for Atesta are identified: the wet adapted (peripherial), including the thorntoni -group and sisyrioides -group, and the wide-adapted, consisting of the houstoni -group. The thorntoni -group is typically a southern Australian species group, distributed in south-eastern and south-western Australian continent and Tasmania. The sisyrioides -group is mainly distributed in southeastern, eastern and northern Australian continent and Tasmania. The distribution of the houstoni -group includes central and peripherial Australian continent.     

渔游蛇雄性生殖周期及其肾性节的生殖生理学研究:Ⅱ.肾性节对精子的体外效应及生化分析

通过精子体外短期孵育表明：渔游蛇（Ｎａｔｒｉｘ ｐｉｓｃａｔｏｒ）肾性节具有营养精子的功能。聚丙烯酰 胺凝胶制备性电泳分离得到了肾性节特异性蛋白Ａ、Ｂ、Ｃ三因子。其中Ａ因子能显著提高精子在 体外的存活率，由Ａ１Ａ２两个亚基构成，分子量分别为６００００和３２０００。而Ｂ、Ｃ因子对精子存活 率无明显的影响。     

Preliminary X-ray investigation of a bifunctional inhibitor from Indian finger millet (ragi).

A bifunctional alpha-amylase/trypsin inhibitor that has two binding sites has been purified from ragi. The inhibitor has been crystallized from its ammonium sulphate solution by the vapour diffusion method. The crystals belong to the orthogonal space group P2(1)2(1)2(1) with unit cell dimensions a = 30.49 A, b = 56.30 A, c = 73.65 A and Z = 4.     

A family of repetitive nucleotide sequences (Sau 3A family) in the genome of 2 forms of the sockeye salmon Oncorhynchus nerka

A family of DNA sequences (Sau3A repeat sequences) has been revealed in genomes of two forms of O. nerka. A DNA fragment belonging to this "family" has been cloned in bacterial plasmid. Its copy number (in genomes of normal (570 +/- 33) and dwarf (66 +/- 12) forms) has been counted. The structural organization of sequences of Sau3A family in genomes of males and females of normal form is not the same. The organization of Sau3A sequences is the same in genomes of dwarf males and dwarf females of normal form, but the quantity of Sau3A sequences copies is smaller. It is supposed that the DNA sequences of Sau3A family bear the sex determination of dwarf form of O. nerka. The fragment of rRNA gene of nerka has been cloned and the number of rRNA gene copies in genomes of normal (200 +/- 62) and dwarf (1690 +/- 24) forms has been defined.     

Ukhtomski?--the teacher (based on memoirs and letters)]

This article has been written by pupil of A.A. Ukhtomsky, well-known professor of Moscow State University M.V. Kirzon. The article discovers the personal qualities of outstanding biologist A.A. Ukhtomsky, who has founded one of the famed physiological scientific schools in the Soviet Union.     

Activation of human pepsinogens

Human pepsinogen A3 and A5 have been purified to chromatographic and electrophoretic homogeneity. At pH 2 pepsinogen A3 activates at a much faster rate than pepsinogen A5. Leu-23-Lys-24 is the first bond cleaved during activation of pepsinogen A3. This bond is also cleaved in pepsinogen A5, but together with the cleavage of Asp-25-Phe-26. Amino acid sequencing shows that pepsinogen A3 has Glu at position 43, whereas pepsinogen A5 has Lys.     

Molecular-genetic organization of plasmid R89S of the incompatibility group Q

A new IncQ plasmid R89S has been analysed by molecular-genetic methods. A restriction map of this plasmid has been constructed and regions of homology with the plasmid RSF1010 have been identified. A genetic map of the plasmid R89S has been prepared based on the deletion and insertion plasmid derivatives. The phenotypic analysis of the derivatives has identified the location of genes coding for replication, incompatibility, mobilization for genetic transfer and resistance to streptomycin in the genome of R89S.     

First crystallization of a phosphoenolpyruvate carboxylase from Escherichia coli

Two different forms of crystal for a phosphoenolpyruvate carboxylase from Escherichia coli were obtained by the hanging-drop vapor diffusion technique, using polyethylene glycol 4000 as precipitant. The hexagonal crystal in space group P6(2)22 (or P6(4)22) has cell dimensions of a = 131 A and c = 325 A, whereas the orthorhombic crystal in space group I222 has a = 119 A, b = 252 A and c = 83 A. A tetrameric molecule (396,244 Mr), a subunit of which contains 883 amino residues, has a crystallographic 2 symmetry in the hexagonal crystal or 222 symmetry in the orthorhombic crystal, respectively.     

The SPR-based biosensor test system for analysis of small compounds interaction with human cytochrome P450 51A1 (CYP51A1)

The SPR-based test for human cytochrome P450 51A1 (CYP51A1) ligand screening has been developed. Applicability of this system has been validated with known azole inhibitors of cytochromes P450. The studied azoles selectively interacted with human cytochrome P450 51A1, which showed the highest affinity towards ketoconazole. The efficiency of the SPR based assay has been tested using 19 steroid and triterpene compounds, which have not been investigated as potential ligands of CYP51A1.     

Crystallization and preliminary diffraction analysis of cholesterol esterase from Candida cylindracea

Cholesterol esterase (EC 3.1.1.13) from the microorganism Candida cylindracea has been crystallized in two forms. Crystals, typically 0.30 x 0.15 x 0.10 mm in size, diffract rotating anode generated x-rays to beyond 3 A are suitable for data collection for an x-ray crystallographic investigation. A monoclinic crystal form in the space group P2(1) was found to have cell dimensions of a = 122.9 A, b = 101.0 A, c = 95.2 A and beta = 108.3 degrees. The asymmetric unit of the cell contains two dimers of 129 kDa each. A second crystal form, in the triclinic space group P1, has cell dimensions of a = 58.6 A, b = 88.7 A, c = 58.6 A, alpha = 93.3 degrees, beta = 113.8 degrees and gamma = 96.0 degrees, and has one dimer per asymmetric unit.     

Determination of protein A I staphylococcus aureus strains isolated from monkeys

Protein A content in Staphylococcus aureus isolated from 6 species of monkeys at the Sukhumi Monkey Nursery has been studied. Protein A has been detected in 73% of the studied strains. One strain isolated from a rhesus macaque has been found to release high amounts of protein A into the environment.     

Single-sweep polarographic investigation of concanavalin A and its interaction with polysaccharide.

A simple, rapid, and sensitive single-sweep polarographic method has been developed for investigation of concanavalin A (con A) and its interaction with selected polysaccharides. In a solution containing 0.001 M 2,2'-bipyridine, 0.015 M hexamethylenetetramine, and 0.1 M sodium chloride, con A exhibits a single-sweep polarographic wave, and the cathodic peak potential is -1.50 V (vs SCE). The peak current varies linearly with con A concentration over a range of 1.0 x 10(-8) to 1.2 x 10(-7) M by derivative single sweep polarography. A preliminary discussion on properties of the con A polarographic wave has been made. In addition, it has been demonstrated that single sweep polarography can be a useful method for studies on interactions of con A with its complementary polysaccharides in solution.