团花(Anthocephalus chinensis)种子和果实中抑制物质的研究

团花的种子中有抑制物质,把种子和果实的其它部分分别用有机溶剂提取和分离,所得粗提物经柱层析和薄层层析纯化后,用气相色谱、高效液相色谱、气-质联用等仪器进行测定,并结合生物鉴定,证明种子和果实其它部分中均含有一定量的脱落酸。种子中的含量为11.7μg/g干重,其它部分15.8μg/g干重。     

Immunological comparison of glyoxalase I from yeast and mammals and quantitative determination of the enzyme in human tissues by radioimmunoassay

Antibodies to glyoxalase I from yeast, rat liver, porcine erythrocytes and human erythrocytes were raised in rabbits. Gel precipitation and immunotitration experiments demonstrated that the mammalian enzymes were immunologically related, but distinct from the yeast enzyme. Fab fragments of the antibodies to human glyoxalase I did not inhibit the catalytic activity, indicating that the antigen binding sites were not directed towards the active site of the enzyme. A radioimmunoassay for glyoxalase I was developed. Quantitative analysis of human adult as well as fetal organs demonstrated that glyoxalase I was present in a concentration of approximately 0.2 micrograms/mg protein in most human tissues.     

Phosphomannosyl receptors of lysosomal enzymes in cardiac and skeletal muscles of young and old mice

The endogenous activity and the binding of high-uptake beta-N-acetylglucosaminidase were assayed in the membranes of heart and skeletal muscles of young (2 months) and old (15 months) NMRI-mice (Mus musculus) to evaluate the age-related changes in the phosphomannosyl receptors of lysosomal enzymes in muscular membranes. The total activities of beta-N-acetylglucosaminidase were significantly higher in cardiac and skeletal muscles of old than young mice. The total and the specific (inhibited by mannose-6-phosphate) binding of beta-N-acetylglucosaminidase to the membranes of cardiac muscle, but not to those of skeletal muscle, were higher in old mice than in young ones. The endogenous activity of beta-N-acetylglucosaminidase was significantly higher in the membranes of skeletal muscles of old mice than in those of young mice. The membranes of heart muscles did not show any difference in the endogenous activities. The saturation properties of the binding of beta-N-acetylglucosaminidase to the phosphomannosyl receptors were very similar in the membranes of heart and skeletal muscles of both age groups. We conclude that during aging the number of phosphomannosyl receptors of lysosomal enzymes increases in the membranes of heart muscle while the occupancy of phosphomannosyl receptors with endogenous ligands increases in the membranes of skeletal muscle.     

Separation of isoenzymatic forms of human serum galactosyltransferase by chromatofocusing and isoelectric focusing. Application to cancerology

Chromatofocusing is used to separate the multiple isoenzyme forms of human serum galactosyltransferase. At least 11 major peaks of activity are observed in normal sera, which are eluted between pH 4.3 and 6.9; a fraction of activity is eluted above pH 7.0. The normal patterns are compared with those obtained with sera from cancer patients and with an ascitic fluid. Chromatofocusing appears as resolutive as agarose isoelectric focusing.     

Expression of the gene encoding protein A in Staphylococcus aureus and coagulase-negative staphylococci

Two shuttle vectors containing the gene for protein A (spa) from Staphylococcus aureus have been constructed to study expression of the gene in various strains of S. aureus and in the coagulase-negative species Staphylococcus epidermidis, Staphylococcus capitis, and Staphylococcus xylosus. One plasmid, pSPA15, contains the complete structural gene for protein A, which binds to the cell wall in various Staphylococcus species. The other plasmid, pSPA16, codes for a truncated protein A lacking the C-terminal part called region X. The latter is exclusively extracellular in all Staphylococcus species tested, which confirms the importance of region X for cell wall binding. The expression of the plasmid-coded protein A in various strains of S. aureus is strongly correlated to the expression of the chromosomal spa gene. The coagulase-negative species expressing plasmid-encoded protein A produce 12 to 30% of the amount coded by the chromosomal spa gene in S. aureus strains Cowan I and A676.     

Isolation of a yeast vector marked by the mutation of multiple resistance to antibiotics

The plasmid mutation AntR determining multiple resistance to antibiotics--tetracycline and cycloheximide in Saccharomyces cerevisiae was earlier obtained and genetically characterized. In this work we describe experiments on cytoduction and transformation, proving the localization of this mutation in the yeast 2 mu DNA. As a result of cotransformation of the sensitive cells carrying a double mutation in the gene LEU2 with the yeast vector marked by LEU2 and 2 mu DNA obtained from the yeast AntR mutant, the Leu+ AntR clones were selected. Though the primary co-transformans contain both plasmids in an unlinked state, we managed to get clones in which the markers AntR and LEU2 were linked. The putative recombinant molecules were cloned in Escherichia coli and then introduced into the yeast recipient cells, differing by the presence of the endogenous 2 mu DNA. Retransformation of cir0 cells results in the appearance of the clones in which LEU2 and AntR markers segregate together. Thus, the result of cotransformation and selection in vivo is that the mutation of multiple resistance was included into the yeast vector plasmid, presumably, in its 2 mu part.     

Effect of various gas atmospheres on the growth and survival of Campylobacter jejuni on beef

Pieces of fresh beef were inoculated with three strains of Campylobacter jejuni. The meat was then allocated to three treatments: (a) vacuum packaged, (b) packaged in an atmosphere of 20% CO2 + 80% N2, and (c) packaged into sterile Petri dishes in anaerobic cultivation boxes, which were filled with a gas mixture of 5% O2 + 10% CO2 + 85% N2. The packaging material in the first two treatments was PA 80/PE 100-PE 100/PA 80/PE 100. The survival of Campylobacter cells was followed at 37 degrees C, 20 degrees C and 4 degrees C for 48 h, 4 days and 25 days, respectively. At 37 degrees C the counts of two Campylobacter strains increased in each package treatment for 48 h. At 20 degrees C and at 4 degrees C the counts of the same two strains decreased by 1 to 2 log units and 0.5 to 1 log unit, respectively, during storage. The survival of the two strains was about the same in all package treatments. The third strain was the most sensitive of the strains studied. At 37 degrees C its numbers increased only in the optimal gas atmosphere; at 20 degrees C the strain was not detectable after 24 to 48 h storage and at 4 degrees C after 4 days storage. The aerobic plate counts were determined for all samples at the same time as Campylobacter counts. The high indigenous bacterial numbers of the meat samples did not appear to have a great effect on the survival or growth of campylobacters.     

Comparative anatomic studies of the vomeronasal complex and the rostral palate of various mammals

The structures of the rostral palate in regard to the vomeronasal complex of different species of mammals were studied. In all cases, we find a very interesting system of furrows which preserves a connection between the nasopalatine ducts and the preoral surroundings. For rodents, lagomorphs, Solenodon, Setifer, and Echinops, we find a special situation in this part of the palate. Here the incisors are not separated by a diastema nor the oral openings of the nasopalatine ducts are overgrown by a bipartite caudal branch of the rhinarium. The results of the anatomic studies of the vomeronasal complex and the rostral palate of the mammals investigated are discussed: First of all, some elements of the vomeronasal complex needed to be analysed in regard to structure and nomenclature, specifically the cartilago paraseptalis with its outer bar, the cartilago ductus nasopalatini and the cartilago palatina. Because of 2 criterions, the vomeronasal complex could be classified as either primitive or progressive. We find a primitive one in Didelphis, Tupaia, Solenodon, Oryctolagus, and all rodents. In contrast, the other insectivores studied and all primates show progressive structures at their vomeronasal complex. Finally, conclusions in regard to the function of the organs of Jacobson are derived from these studies. The significance of the "flehmen" mechanism for the functioning of the organs is questioned.