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11.
Similarity of the oxidation products of L-cystathionine by L-amino acid oxidase to those excreted by cystathioninuric patients 总被引:1,自引:0,他引:1
G Ricci L Santoro M Achilli R M Matarese M Nardini D Cavallini 《The Journal of biological chemistry》1983,258(17):10511-10517
L-Cystathionine is oxidized by snake venom L-amino acid oxidase at a rate about half that with L-leucine at pH 8.5. The appearance of an absorbance at 296 nm and quantitation of the products of oxidation in the presence of catalase indicate formation in the solutions of a seven-membered ketimine ring produced by cyclization of the monoamino monoketo derivative of cystathionine. A limited double deamination has also been observed. In the absence of catalase, S-(carboxymethyl)homocysteine and S-(beta-carboxyethyl)cysteine have been identified together with ninhydrin-unreactive compounds yielding the above mentioned carboxy compounds upon hydrolysis with HCl. Authentic samples of the monoamino monoketo analogs of cystathionine have been prepared and compared with the enzymatic products. Cyclization of the synthetic products into the ketimine ring is pH-dependent as established by UV spectrum and other assays. Compounds derived from either the oxidation or the reduction of the ketimine have been prepared. It was found that many products of enzymatic and chemical changes of cystathionine and its ketimine described in the present paper are identical with those identified in the urine of cystathioninuric patients. This result indicates the occurrence in humans of secondary metabolic routes of cystathionine centered on the production of cystathionine ketimine, in equilibrium with the open form, which in cystathioninurics is revealed by the lack of cystathionase. 相似文献
12.
L Adoncecchi W Marrocco G Perrone A Santoro C Suraci P Pecora 《Bollettino della Società italiana di biologia sperimentale》1983,59(7):977-982
Serum glycerol and NEFA content variations are examined before and after labor in obese and normal weighing women (35 subjects). Blood glycerol and NEFA are shown to increase before delivery. Glycerol values are shown to drop to normal immediately after delivery, while NEFA values diminish to a lesser extent. Statistical analysis shown that blood glycerol increase could be pregnancy-dependent in both normal weighing and obese women, but that NEFA increase could be pregnancy-dependent in normal weighing women only. Obesity increases blood glycerol and NEFA concentration considerably, thus masking the effects of pregnancy. 相似文献
13.
T J Santoro W R Benjamin J J Oppenheim A D Steinberg 《Journal of immunology (Baltimore, Md. : 1950)》1983,131(1):265-268
Disturbances in immune interferon (IFN gamma) activity have been implicated in the development of human systemic lupus erythematosus (SLE) and the spontaneous disease sustained by autoimmune-prone mice. We therefore investigated the cellular basis for IFN gamma production in MRL-Ipr/Ipr mice and examined the relationship between synthesis of interleukin 2 (IL 2) and IFN gamma. In vitro IL 2 and IFN gamma production in 3 to 6-mo-old, autoimmune MRL-Ipr/Ipr and MRL-+/+ mice was compared with that seen in age- and sex-matched, immunologically normal CBA/J mice. 5 X 10(6) spleen cells were pulsed with 5 micrograms of concanavalin A (Con A), and the cellfree supernatant was assayed for IL 2 and IFN gamma activity at various times up to 72 hr. We found that peak levels of IL 2 in MRL mice were less than 10% of those in the CBA/J. Yet, production of IFN gamma by cells from the autoimmune and normal strains was quite comparable. The addition of murine IL 2 to optimally Con A-stimulated cells from the MRL-Ipr/Ipr or normal mice did not affect the subsequent peak production of IFN gamma. Although the primary producers of IFN gamma in cultures of normal mice bear the Lyt-2+ phenotype, the Lyt-1+2- T-cell subset was found to be the principal source of IFN gamma in the aged MRL-Ipr/Ipr. These data suggest that Lyt-1+ cells from MRL-Ipr/Ipr mice may be differentially responsive to the signal delivered by the same mitogenic lectin with respect to lymphokine production and may indicate a distorted commitment of such cells toward production of IFN gamma and repression of IL 2 synthesis. The relationship between hypoproduction of IL 2, this usual source of IFN gamma, and the autoimmune disease sustained by MRL-Ipr/Ipr mice remains unclear. 相似文献
14.
Cloning and sequencing of a full length cDNA coding for human retinol-binding protein. 总被引:12,自引:3,他引:9
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V Colantuoni V Romano G Bensi C Santoro F Costanzo G Raugei R Cortese 《Nucleic acids research》1983,11(22):7769-7776
We have isolated and sequenced a cDNA clone coding for human Retinol Binding Protein. The sequence indicates that Retinol Binding Protein is synthesized as a single polypeptide chain precursor which is then matured to the secreted protein by removal of a leader peptide. Southern and Northern blot analysis suggest that the gene is present in one or few copies per haploid genome and is transcribed in a single mRNA species. 相似文献
15.
Sequence of human haptoglobin cDNA: evidence that the alpha and beta subunits are coded by the same mRNA. 总被引:10,自引:3,他引:7
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G Raugei G Bensi V Colantuoni V Romano C Santoro F Costanzo R Cortese 《Nucleic acids research》1983,11(17):5811-5819
We have isolated and sequenced a cDNA clone coding for human haptoglobin. Our sequence shows that haptoglobin is very likely synthesized as a single polypeptide chain which is then cleaved at an Arg residue to generate its two characteristic alpha and beta subunit. Southern blot analysis suggests that there are at least two copies of the haptoglobin gene per haploid genome. 相似文献
16.
17.
Activated platelets express IL-1 activity 总被引:7,自引:0,他引:7
C M Hawrylowicz S A Santoro F M Platt E R Unanue 《Journal of immunology (Baltimore, Md. : 1950)》1989,143(12):4015-4018
Suspensions of washed human platelets express IL-1 activity after activation with agents such as thrombin, collagen, ADP, or epinephrine as judged by the ability of the platelet suspensions to support the growth of a T cell line, D10.G4.1, which exhibits a growth requirement for IL-1. Unactivated platelets express little IL-1 activity. The IL-1 activity expressed by activated platelets appears to be entirely associated with the platelet surface. No IL-1 activity was detected in supernatants derived from suspensions of activated platelets. A mAb specific for IL-1 beta inhibited 90% of the activity expressed by thrombin-activated platelets, whereas a mAb specific for IL-1 alpha inhibited approximately 20% of the activity. A control mAb was without an effect. These results indicate that activated platelets express surface-associated IL-1 activity. Platelet surface IL-1 may provide a mechanism for altering in an extremely localized and rapid manner the properties of IL-1 responsive cells with which platelets come in direct contact during processes of inflammation and vessel wall damage. 相似文献
18.
Wine vinegar is a product obtained from wine acidification which contains at least 5% by wt. of acetic acid, in general without any additives or colorings.
Aspects studied in this work include: the determination of the taste group thresholds (geometric mean of the individual best-estimate thresholds "BET") of two different acids (citric and acetic acids) in aqueous solution and spanish vinegars produced from table and sherry wines. The results obtained suggest that wine vinegar can be considered something more than just an acidulant agent.
In order to evaluate differences among wine vinegars, discriminant tests for twenty-five spanish vinegars (sherry, table and flavored vinegars) were applied. Six of the twelve attributes freely chosen by assessors allowed grouping of the spanish wine vinegars according to their sensory aspects. 相似文献
Aspects studied in this work include: the determination of the taste group thresholds (geometric mean of the individual best-estimate thresholds "BET") of two different acids (citric and acetic acids) in aqueous solution and spanish vinegars produced from table and sherry wines. The results obtained suggest that wine vinegar can be considered something more than just an acidulant agent.
In order to evaluate differences among wine vinegars, discriminant tests for twenty-five spanish vinegars (sherry, table and flavored vinegars) were applied. Six of the twelve attributes freely chosen by assessors allowed grouping of the spanish wine vinegars according to their sensory aspects. 相似文献
19.
João Ricardo Sato Claudinei Eduardo Biazoli Ana Paula Arantes Bueno Arthur Caye Pedro Mario Pan Marcos Santoro Jessica Honorato-Mauer Giovanni Abrahão Salum Marcelo Queiroz Hoexter Rodrigo Affonseca Bressan Andrea Parolin Jackowski Euripedes Constantino Miguel Sintia Belangero Luis Augusto Rohde 《Genes, Brain & Behavior》2023,22(2):e12838
20.