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111.
Jamal Bayad Nicole Sabolovic Denyse Bagrel Athanase Visvikis Maria Wellman Gerard Siest 《Cell biology and toxicology》1990,6(2):157-170
Eighteen IgGl monoclonal antibodies (blabs) have been produced against gamma-glutamyl transferase (GGT) from rat kidney. They were specific to the light subunit of the enzyme with affinity constants ranging from 0.3 to 7.5 108 M–1, while they did not react with GGT from other sources i.e. human and pig kidney, rat and guinea pig liver, suggesting species and organ specificity. Two of the blabs (N° 11 and 21) lost their immunoreactivities towards rat kidney GGT in the presence of N-acetyl-neuraminic acid, while immunoreactivities of the other blabs were unchanged. Furthermore, Mabs No 11 and 21 did not react with desialylated rat kidney GGT. These findings suggest that N-acetyl-neuraminic acid is involved in the epitopes recognized by these two Mabs.Abbreviations ELISA
enzyme linked immunosorbent assay
- GGT
gamma-glutamyltransferase
- Mab
monoclonal antibody
- SDS-PAGE
sodium dodecyl sulfate-polyacrylamide gel electrophoresis 相似文献
112.
Elvira D'Alessandro Corinna De Matteis Vaccarella Maria Luisa Lo Re Francesco Cappa Angela D'Alfonso Stefania Discepoli Maria Rosa Della Penna Giuseppe Del Porto 《Human genetics》1988,80(2):203-204
Summary Pericentric inversion of chromosome 19 has been found in several members of three unrelated families from a restricted geographical region. In one of the families, an additional pericentric inversion of chromosome 9 was observed. Reproductive problems, multiple abortions in two families and a neonatal death in the third, were present. A review of previously described cases is included, and the genetic risk connected with this type of rearrangement is also discussed. 相似文献
113.
Maria Di Bello Valeria Lucchini Stefania Chiari Roberto Colleoni Nicoletta Colombo Alberto Mantovani Paola Allavena 《Cancer immunology, immunotherapy : CII》1988,27(1):63-68
Summary Expression of HLA-DR antigens by purified preparations of human ovarian carcinoma cells freshly isolated from surgical specimens was examined in parallel with the capacity of tumor cells to elicit a blastogenic response from autologous lymphocytes in mixed lymphocyte-tumor culture (MLTC) assay. Of 21 tumor preparations, 11 (52%) reacted with monoclonal antibodies 279 and/or 949 specific for a monomorphic determinant of HLA-DR antigens, with heterogeneous positivity, ranging between 30% and 95%. In this series of patients positive MLTC occurred in 8/21 individual experiments. The HLA-DR expression was proportionally similar in tumors giving positive MLTC (4/8=50%) and negative MLTC (7/13=53%). The lack of correlation between DR expression on tumor cells and stimulatory activity in autologous MLTC and the fact that DR-negative tumors could induce lymphocyte stimulation, support the hypothesis that blastogenesis occurs upon recognition of tumor-associated antigens, different from DR molecules, possibly tumor-specific antigens. 相似文献
114.
Bianca Colonna Maria Bernardini Gioacchino Micheli Francesco Maimone Mauro Nicoletti Mariassunta Casalino 《Plasmid》1988,20(3):221-231
Tn1935, a 23.5-kb transposon mediating resistance to ampicillin, kanamycin, mercury, spectinomycin, and sulfonamide was isolated from pZM3, an IncFIme virulence plasmid from Salmonella wien. Tn1935 possesses the entire sequence of Tn21 and contains two additional DNA segments of 0.95 and 2.7 kb carrying the ampicillin and kanamycin resistance genes, respectively. The latter is part of a composite element since it is flanked by two IS15-like insertion sequences (IS1936) in direct orientation. IS1936 is about 800 bp long and is closely related to IS15 delta, IS26, IS46, IS140, and IS176. Functional analysis of IS1936-mediated cointegrates shows that both insertion sequences are active and able to form cointegrates at the same frequency. Resolution of the cointegrates requires the presence of the host Rec system. The presence of the composite IS1936-element within Tn1935 supports the hypothesis that multidrug resistance transposons evolved by insertion of antibiotic determinants which are themselves transposable. 相似文献
115.
The characterization of centromeric proteins is facilitated using anti-centromere antibodies present in the sera of patients with the CREST variant of scleroderma. We have employed these sera to determine whether or not those proteins are present in different mammalian species, as well as to study their tissue distribution. Here, we describe the immunofluorescent pattern and the proteins recognized by CREST sera in dividing and resting cells from mouse, rat, swine, hamster, rabbit, and man. In nuclear preparations from cultured cells, thymocytes and spermatozoa from these species, the antigens recognized by CREST sera are proteins of 18 to 20 kDa in all species tested, except in rat. Additionally, two peptides of 80 and 140 kDa were observed in human preparations. In contrast, a 50 kDa peptide is the primary protein detected by the sera in rat nuclei. 相似文献
116.
Occurrence of a Large Ca2+ -Independent Release of Glutamate During Anoxia in Isolated Nerve Terminals (Synaptosomes) 总被引:2,自引:0,他引:2
Isolated rat cerebral cortical synaptosomes made anoxic by addition of cyanide developed an inhibition of the Ca2+-dependent release of glutamate 2 min after the addition of the metabolic inhibitor when the intrasynaptosomal ATP/ADP ratio decreased below 1.7. In contrast, cyanide induced a continuous efflux of glutamate through a Ca2+-independent pathway that accounted for the release of 25% of total intrasynaptosomal glutamate in 5 min. The results suggest that a Ca2+-independent release of glutamate could be implicated in the neurotoxic action of this amino acid during anoxia. 相似文献
117.
Anna Maria Greco Pasquale Gambardella Raffaella Sticchi Diego D'aponte Pietro De Franciscis 《Chronobiology international》1988,5(3):217-225
Circadian rhythms of serotonin (5HT), its precursors tryptophan (TP) and 5-hydroxy-tryptophan (5HTP) and its acid catabolite 5-hydroxy-indoleacetic acid (5HIAA), were determined in the hypothalamus of control rats and rats which had been treated continuously with subcutaneous imipramine (10 mg/kg/day) for 2 weeks.
Rats were individually housed and entrained to LD12:12. Controls showed the 5HT and TP peaks in the light and dark periods respectively, as reported in the literature, but no inverted correlation (antiphase) between SHT and 5HIAA rhythms.
Imipramine significantly modified circadian rhythm characteristics: the 5HT acrophase was advanced, that of TP and 5HIAA was delayed. Imipramine also significantly increased hypothalamic SHT and TP concentrations. 相似文献
Rats were individually housed and entrained to LD12:12. Controls showed the 5HT and TP peaks in the light and dark periods respectively, as reported in the literature, but no inverted correlation (antiphase) between SHT and 5HIAA rhythms.
Imipramine significantly modified circadian rhythm characteristics: the 5HT acrophase was advanced, that of TP and 5HIAA was delayed. Imipramine also significantly increased hypothalamic SHT and TP concentrations. 相似文献
118.
C Beas-Zárate A R del Angel Meza A Morales-Villagran A Feria Velasco 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1988,89(2):173-177
1. Endogenous serotonin (5-HT), 5-hydroxyindol acetic acid (5-HIAA) content and exogenous 5-HT uptake (Km and Vmax) were measured in different brain regions (cerebellum, diencephalon, brain stem and telencephalon) of rats fed with a corn diet and restricted protein (8%) diet during 6 weeks. 2. A reduction of 5-HT levels was found in all regions studied of animals fed a corn diet, whereas, 5-HIAA was only decreased in brain stem and diencephalon. 3. An important increase in Km and Vmax were registered in brain stem and diencephalon of protein restricted animals, whereas, an increase of 5-HT uptake affinity in cerebellum, brain stem and telencephalon (35, 42 and 33% respectively) was observed. Simultaneously, under corn diet conditions, the Vmax decreased 40, 30 and 34% respectively in those regions. 4. It is suggested that the brain stem was the more sensitive area under nutritional restricted conditions and the development of some possible compensatory mechanisms of the 5-HTergic system is discussed. 相似文献
119.
Peter Aaby Jette Bukh Ida Maria Lisse Maria Clotilde da Silva 《BMJ (Clinical research ed.)》1988,296(6631):1225-1228
The mortality from measles was studied in an urban area of Guinea-Bissau one year before and five years after the introduction of a vaccination programme. The years after the introduction of immunisation saw a decline in mortality among unvaccinated children with measles. This decline occurred despite a lower age at infection and an increasing prevalence of malnourished children. State of nutrition (weight for age) did not affect the outcome of measles infection. The incidence of isolated cases, however, increased in the period after the introduction of measles vaccination. As mortality was lower among these cases, diminished clustering explained some of the reduction in mortality. Comparison between the urban district and a rural area inhabited by the same ethnic group showed a lower age at infection, less clustering of cases, and lower case fatality ratios in the urban area.Endemic transmission of measles in urban districts leads to less clustering of cases, which may help explain the usually lower case fatality ratios in these areas. As measles vaccination increases herd immunity and diminishes clustering of cases, it may reduce mortality even among unvaccinated children who contract the disease. 相似文献
120.
M. Pilar López M. Jose Gómez-Lechón Jose V. Castell 《In vitro cellular & developmental biology. Plant》1988,24(6):511-517
Summary This study examines the factors involved in the rapid glycolysis and glycogenolysis that occur during the first stages of
hepatocyte culture: a) Shortly after seeding glycolysis, estimated as lactate released to culture medium, increased 10 times
in comparison to that reported in vivo. By 8 to 9 h of culture, hepatocytes were nearly glycogen-depleted even in the presence
of insulin. b) 6-Phosphofructo-2-kinase remained 100% active during this period. The proportion of the initial active phosphorylase
(87%) decreased to 57% by 7 h of culture. c) Fructose 2,6-bisphosphate content was initially similar to that found in liver
of fed animals, decreased after seeding and increased thereafter up to four times the initial concentration. In spite of changes
in the concentration of this activator, the glycolytic rate remained high and constant. d) ADP and AMP increased sharply after
cell plating, reaching values 1.7 and 3.5 times higher. The rise in AMP levels may be involved in the activation of glycolysis
and glycogenolysis, because this metabolite is known to act as an allosteric activator of phosphofrucktokinase and glycogen
phosphorylase. This metabolic situation resembles that of cells under hypoxia.
Part of this work was presented at the 38th Annual Meeting of the Tissue Culture Association, Washington, DC, May 1987. 相似文献