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1.
2.
Lodovica Vergani Marina Fanin Andrea Martinuzzi Andrea Galassi Andrea Appi Rosalba Carrozzo Maurizio Rosa Corrado Angelini 《Molecular and cellular biochemistry》1990,98(1-2):225-230
Summary FABPs in the various tissues play an important role in the intracellular fatty acid transport and metabolism. Reye's syndrome (RS) and multisystemic lipid storage (MLS) are human disorders characterized by a disturbance of lipid metabolism of unknown etiology. We investigated for the first time L-FABP in these two conditions. Affinity purified antibodies against chicken L-FABP were raised in rabbits, and found to cross-react specifically with partially purified human L-FABP. L-FABP content in liver samples of two patients with RS and MLS was investigated by immuno-histochemistry, SDS-PAGE and ELISA. L-FABP immuno-histochemistry showed increased reactivity in the liver of RS patient and normal reactivity in MLS liver. L-FABP increase in RS liver was confirmed by densitometry of SDS-PAGE and ELISA method. By these two methods the increase amounted to 180% and 199% (p < 0.02), respectively, as compared to controls. A possible role of L-FABP in the pathogenesis of RS is discussed. 相似文献
3.
Fish skin bacteria: Colonial and cellular hydrophobicity 总被引:1,自引:0,他引:1
Dental plaque is a complex community of bacteria coexisting in an environment frequently limited by carbon and energy sources. UnlikeStreptococcus mutans, other oral streptococci such asS. milleri andS. sanguis have an absolute requirement for and actually consume all available arginine when grown glucose limited in a chemically defined medium. The conditions, particularly in terms of arginine concentration, under which the dental plaque bacteriaS. mutans andS. milleri would coexist under glucose-limiting conditions were investigated. The minimum level of arginine supporting optimal growth ofS. milleri was found to be ca. 50M, and above this level these strains outcompetedS. mutans. However, coexistence withS. mutans could be achieved at arginine levels of 14–40M, depending upon theS. milleri andS. mutans strains used. Under such dual limitation,S. milleri was unable to respond to glucose pulses but did respond to pulses of arginine and arginine plus glucose. One of the twoS. milleri strains did not tolerate low pH. In contrast,S. mutans did not tolerate high pH whereasS. milleri was unaffected. This is relevant to dental plaque where arginine catabolism produces a pH rise. Additionally, arginine is an important nutrient since it can be used as an energy source by some oral streptococci. 相似文献
4.
Fioretta Rambelli Maurizio Brigotti Simonetta Sperti Lucio Montanaro 《Bioscience reports》1987,7(9):737-743
Diphtheria toxin fragment A interacts with Cibacron blue in solution, although it is not retained by blue Sepharose columns. Difference spectral titration of fragment A with the dye gives a dissociation constant of the order of 10–5 M and a 11 stoichiometry for the complex. In equilibrium dialysis experiments Cibacron blue behaves as a competitive inhibitor of the binding of NAD to diphtheria toxin fragment A. The dye inhibits in a non-competitive way the fragment A-catalysed transfer of ADP-ribose from NAD to elongation factor 2 (EF2). By affinity chromatography on blue Sepharose a binding of EF2 and of ADP-ribosyl-EF2 with the dye is also demonstrated. GDP, GTP and GDP(CH2)P are able to displace EF2 from blue Sepharose. 相似文献
5.
Summary A new distinctive feature between the two Mediterranean species of Tethya, T. aurantium and T. citrina has been found in the body arrangement of different types of micrasters. Contrary to the previous assumptions, T. aurantium has two clearly distinct categories of micrasters: the chiaster-tylaster in the cortex and the larger, slender oxyaster in the choanosome. T. citrina has only slightly differentiated micraster sets in the cortex and choanosome; in the latter the shape of micrasters is close to that of oxyasters. SEM analysis shows that differences in micraster shape depend on the cylindrical or conical form of rays and on the distribution, density and strength of the microspines along their axis. The relationship between the degree of micraster differentiation and the development of the cortex in the two species is discussed. 相似文献
6.
Fiorenzo A. Peverali Maurizio D'Esposito Dario Acampora Giuseppe Bunone Mario Negri Antonio Faiella Anna Stornaiuolo Maria Pannese Enrica Migliaccio Antonio Simeone Giuliano Della Valle Edoardo Boncinelli 《Differentiation; research in biological diversity》1990,45(1):61-69
Mammalian genes containing a class-I homeobox (HOX genes) are highly expressed in the embryonic nervous system. As a first step towards the molecular analysis of the role these genes play in neural cells, we studied the expression of four human HOX genes in five neuroblastoma (NB) cell lines - SK-N-BE, CHP-134, IMR-32, SK-N-SH and LAN-1 - during the process of differentiation induced by treatment with retinoic acid (RA). The four genes, HOX1D, 2F, 3E and 4B, located at corresponding positions in the four HOX loci, share a high degree of sequence similarity with the Drosophila Deformed homeotic gene and constitute a homology group, group 10. One of these genes, HOX1D, is not expressed in the cells used, whereas the other three are highly expressed in untreated and RA-induced NB cells, even though the expression pattern in the various lines is slightly different for the three genes. Our analysis reveals a complex and specific expression pattern in these lines, paving the way to an identification of different NB-cell populations by means of specific HOX gene expression schemes. On the other hand, in every line studied, morphological maturation toward a neuronal differentiated phenotype appears to be associated with increased HOX gene expression. 相似文献
7.
A hemagglutinating activity was detected in a synaptic vesicle-enriched fraction prepared from adult rat brain, using trypsinized glutaraldehyde-fixed rabbit erythrocytes. The specific activity of the fraction, in two series of experiments, was 7.5 and 16-fold higher than in the other subcellular fractions. The activity was absent from the synaptosome cytosol. In a study using twenty-five different carbohydrates and glycoproteins, best inhibitors were N-acetylneuraminic acid and N-glycolylneuraminic acid, together with bovine submaxillary mucin and a glycopeptide fraction prepared from rabbit erythrocyte membranes. The activity was thermolabile and very sensitive to proteolytic enzymes (but insensitive to neuraminidase) indicating that a protein (agglutinin) is responsible for the activity. Experiments using detergents and high ionic strength showed that the agglutinin is tightly bound to membranes, inactivated by the so-called non denaturing detergents, and stable in diluted sodium dodecyl sulphate. Hypotheses are discussed on the possible function of the agglutinin. 相似文献
8.
9.
Dr. G. Schleicher W. E. Stumpf U. Drews K. U. Thiedemann M. Sar 《Histochemistry and cell biology》1985,82(5):453-461
Summary The distribution of specific nuclear binding sites for androgens and estrogens in the male accessory sex organs of the mouse
was assessed by autoradiography with3H dihydrotestosterone (3H DHT) and3H estradiol (3H E2).
With3H DHT nuclear labeling differed among the epithelia of the organs. It was high in seminal vesicle and ampullary gland, moderate
in ventral prostate, urethral gland, prostatic excretory ducts and the ampulla ductus deferentis, low in dorsal prostate and
low or absent in coagulation gland. With3H E2, in contrast, epithelial nuclear labeling was high only in coagulation gland, moderate or low in seminal vesicle, low or
absent in ventral and dorsal prostate and absent in ampullary gland and ampulla ductus deferentis. In the lamina propria of
all organs nuclear labeling with3H DHT was generally moderate and existed only in some cells, with the highest number in the ampulla ductus deferentis. With3H E2, nuclear labeling in the lamina propria showed a high intensity in all organs, except in ventral and dorsal prostate which
remained unlabeled. Many labeled cells were found in the deferent duct and its ampulla, while in the other organs only a few
cells showed nuclear labeling with3H E2. In the smooth muscle sheath of all organs, some muscle cells were moderately labeled with3H DHT, but not with3H E2.
The results indicate the presence of nuclear receptors in male accessory sex organs for both dihydrotestosterone and estradiol.
The differential patterns of3H DHT and3H E2 nuclear uptake suggest differential sensitivities of the individual organs and their tissue compartments for androgens and
estrogens.
Supported by PHS grant NSO9914 to W.E.S. and Deutsche Forschungsgemeinschaft Dr94/4 to U.D. The work of Dr. Schleicher and
his stay in Chapel Hill were additionally sponsored by Studienstiftung des Deutschen Volkes and Boehringer-Ingelheim Fonds 相似文献
10.
Structural Genes for a Newly Recognized Acetolactate Synthase in Escherichia coli K-12 总被引:23,自引:15,他引:8 下载免费PDF全文
Maurilio De Felice John Guardiola Bruno Esposito Maurizio Iaccarino 《Journal of bacteriology》1974,120(3):1068-1077
Evidence is reported that shows the presence in Escherichia coli K-12 of a newly found acetolactate synthase. This enzyme is the product of two genes, ilvH and ilvI, both located very close to leu. Amber mutations have been found in both genes and therefore their products are polypeptides. Mutations in the ilvH gene cause the appearance of an acetolactate synthase activity which is relatively resistant to valine inhibition and can be separated by adsorption on hydroxylapatite from another activity present in the extract and more sensitive to valine inhibition than the former. A mutant altered in the ilvI gene was isolated among the revertants sensitive to valine inhibition of an ilvH mutant. Such a mutant lacks the resistant acetolactate synthase. A temperature-sensitive revertant of the ilvI mutant contained a temperature-sensitive acetolactate synthase. Thus ilvI is the structural gene for a specific acetolactate synthase. The activity of the ilvH gene product has been measured by adding an extract containing it to a purified ilvI acetolactate synthase, which, upon incubation, became more sensitive to valine inhibition. Conversely, a valine-sensitive acetolactate synthase (the product of the ilvH and the ilvI genes) became more resistant to valine inhibition upon incubation with an extract of a strain containing a missense ilvH gene product. 相似文献