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2.
Phys Rev Lett ; 107(20): 202501, 2011 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-22181727

RESUMO

A new technique to measure (p,n) charge-exchange reactions in inverse kinematics at intermediate energies on unstable isotopes was successfully developed and used to study the (56)Ni(p,n) reaction at 110 MeV/u. Gamow-Teller transition strengths from (56)Ni leading to (56)Cu were obtained and compared with shell-model predictions in the pf shell using the KB3G and GXPF1A interactions. The calculations with the GXPF1A interaction reproduce the experimental strength distribution much better than the calculations that employed the KB3G interaction, indicating deficiencies in the spin-orbit and proton-neutron residual potentials for the latter. The results are important for improving the description of electron-capture rates on nuclei in the iron region, which are important for modeling the late evolution of core-collapse and thermonuclear supernovae.

3.
Am J Med ; 92(4): 368-74, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1558083

RESUMO

PURPOSE: To prospectively assess rheumatic manifestations of human immunodeficiency virus (HIV) disease in a municipal hospital clinic population in which intravenous drug use was the most common risk factor for HIV infection. PATIENTS AND METHODS: Patients with documented HIV infection were evaluated for rheumatic disease using a standardized questionnaire and examination. Patients with fibromyalgia were compared with HIV-infected patients without fibromyalgia and with fibromyalgia patients without known risk factors for HIV infection. RESULTS: Thirty-seven of 140 patients with HIV infection had muskuloskeletal symptoms. Three of these 37 patients had arthritis, but none had Reiter's syndrome or psoriatic arthritis. Thirty (81%) of 37 patients had chronic musculoskeletal symptoms (for 3 months or longer). Twenty of 30 patients with chronic musculoskeletal symptoms had polyarthralgia, and of those, 15 (75%) were found to have either definite or probable fibromyalgia syndrome. Therefore, fibromyalgia syndrome was found in 41% of HIV-infected patients with musculoskeletal symptoms and in approximately 11% of all HIV-infected patients. Fibromyalgia patients with HIV infection had a longer duration of HIV infection (p = 0.01) and more frequently reported past depressed mood (p = 0.001) than HIV-infected patients without fibromyalgia. Compared with 301 patients with fibromyalgia syndrome and no known risk behavior for HIV, known HIV-infected patients with fibromyalgia were more commonly male (p = 0.001) and reported current depressed mood more frequently (p = 0.0001). CONCLUSION: Few patients with arthritis were noted among HIV-infected patients who had intravenous drug use as risk behavior. By comparison, fibromyalgia syndrome appeared to be a common cause of musculoskeletal symptoms in this patient population.


Assuntos
Fibromialgia/complicações , Infecções por HIV/complicações , Doença Aguda , Adulto , Artrite/complicações , Doença Crônica , Depressão/complicações , Fadiga/complicações , Feminino , Humanos , Articulações/patologia , Masculino , Músculos/patologia , Estudos Prospectivos , Doenças Reumáticas/complicações , Fatores Sexuais , Transtornos do Sono-Vigília/complicações , Síndrome
4.
J Biol Chem ; 259(4): 2283-90, 1984 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-6698965

RESUMO

Heparan sulfate (HS), a prominent component of vascular endothelial basal lamina, is cleaved into large Mr fragments and solubilized from subendothelial basal lamina-like matrix by metastatic murine B16 melanoma cells. We have examined the degradation products of HS and other purified glycosaminoglycans produced by B16 cells. Glycosaminoglycans 3H-labeled at their reducing termini or metabolically labeled with [35S]sulfate were incubated with B16 cell extracts in the absence or presence of D-saccharic acid 1,4-lactone, a potent exo-beta-glucuronidase inhibitor, and glycosaminoglycan fragments were analyzed by high speed gel permeation chromatography. HS isolated from bovine lung, Engelbreth-Holm-Swarm sarcoma, and subendothelial matrix were degraded into fragments of characteristic Mr, in contrast to hyaluronic acid, chondroitin 6-sulfate, chondroitin 4-sulfate, dermatan sulfate, keratan sulfate, and heparin which were essentially undegraded. Heparin, but not other glycosaminoglycans, inhibited HS degradation. The time dependence of HS degradation into particular Mr fragments indicated that HS was cleaved at specific intrachain sites. In order to determine specific HS cleavage points, HS prereduced with NaBH4 was incubated with a B16 cell extract and HS fragments were separated. The newly formed reducing termini of HS fragments were then reduced with NaB[3H]4, and the fragments hydrolyzed to monosaccharides by trifluoroacetic acid treatment and nitrous acid deamination. Since 3H-reduced terminal monosaccharides from HS fragments were overwhelmingly (greater than 90%) L-gulonic acid, the HS-degrading enzyme responsible is an endoglucuronidase (heparanase).


Assuntos
Glucuronidase , Glicosídeo Hidrolases/metabolismo , Melanoma/enzimologia , Animais , Linhagem Celular , Glicosaminoglicanos , Heparitina Sulfato , Cinética , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/secundário , Camundongos , Especificidade por Substrato
5.
Science ; 220(4597): 611-3, 1983 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-6220468

RESUMO

After transport in the blood and implantation in the microcirculation, metastatic tumor cells must invade the vascular endothelium and underlying basal lamina. Mouse B16 melanoma sublines were used to determine the relation between metastatic properties and the ability of the sublines to degrade enzymatically the sulfated glycosaminoglycans present in the extracellular matrix of cultured vascular endothelial cells. Highly invasive and metastatic B16 sublines degraded matrix glycosaminoglycans faster than did sublines of lower metastatic potential. The main products of this matrix degradation were heparan sulfate fragments. Intact B16 cells (or their cell-free homogenates) with a high potential for lung colonization degraded purified heparan sulfate from bovine lung at higher rates than did B16 cells with a poor potential for lung colonization. Analysis of the degradation fragments indicated that B16 cells have a heparan sulfate endoglycosidase. Thus the abilities of B16 melanoma cells to extravasate and successfully colonize the lung may be related to their capacities to degrade heparan sulfate in the walls of pulmonary blood vessels.


Assuntos
Glicosaminoglicanos/metabolismo , Heparitina Sulfato/metabolismo , Melanoma/fisiopatologia , Invasividade Neoplásica , Metástase Neoplásica , Animais , Linhagem Celular , Glicosídeo Hidrolases/metabolismo , Melanoma/enzimologia , Camundongos
6.
Anal Biochem ; 130(2): 461-8, 1983 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-6223541

RESUMO

A high-speed gel-permeation chromatographic system for analyzing glycosaminoglycans which uses two 0.7 X 75-cm stainless-steel columns containing Fractogel (Toyopearl) TSK HW-55(S), was developed. Glycosaminoglycans were applied and eluted with a 0.2 M sodium chloride solution and monitored by ultraviolet absorption at 210 nm or radioactivity. The best resolution of glycans was obtained at 55 degrees C at a flow rate of 1.0 ml/min. Acidic and neutral glycans in the molecular weight (Mr) range 600-60,000 eluted within 45 min. A linear relationship was found between retention time and molecular weight using standard glycosaminoglycans, chitin oligosaccharides, and a porcine thyroglobulin glycoprotide. This system was used to analyze the heparan sulfate synthesized by PYS-2 embryonic carcinoma cells and the degradation products produced by incubating it with extracted glycosidases from metastatic B16 melanoma cells. The results indicated that B16 melanoma cells contain at least two different heparan sulfate degradative activities, one of which appears to be an endoglycosidase.


Assuntos
Glucuronidase , Glicosaminoglicanos/análise , Glicosaminoglicanos/isolamento & purificação , Glicosídeo Hidrolases/metabolismo , Heparitina Sulfato/isolamento & purificação , Teratoma/metabolismo , Animais , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Camundongos , Neoplasias Experimentais/enzimologia , Neoplasias Experimentais/metabolismo , Teratoma/enzimologia
8.
Carbohydr Res ; 96(2): 271-90, 1981 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-6458358

RESUMO

The disaccharide 2-acetamido-2-deoxy-beta-D-glucopyranosyl-(1 goes to 3)-D-[1-3H]-galactitol, prepared from keratan sulfate, was rapidly hydrolyzed by the A and B isoenzymes of normal human liver hexosaminidase (EC 3.2.1.30), and by the B isoenzyme prepared from the liver of a patient who had died of Tay-Sachs disease. The disaccharide substrate was also hydrolyzed by extracts of normal, cultured-skin fibroblasts, and fibroblasts of patients with Tay-Sachs disease, whereas it was not hydrolyzed by fibroblast extracts of patients with Sandhoff disease. Thus, effective degradation of keratan sulfate, secondary to a defect of the beta subunits present in the A and B isoenzymes of hexosaminidase, may contribute to the appearance of skeletal lesions in patients affected by Sandhoff disease.


Assuntos
Acetilglucosaminidase/metabolismo , Glicosaminoglicanos , Hexosaminidases/metabolismo , Isoenzimas/metabolismo , Sulfato de Queratano , Fígado/enzimologia , Acetilglucosaminidase/isolamento & purificação , Células Cultivadas , Fibroblastos/enzimologia , Humanos , Pele/enzimologia , Especificidade por Substrato , Doença de Tay-Sachs/enzimologia
9.
Biochim Biophys Acta ; 674(2): 178-87, 1981 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-6786361

RESUMO

The interaction in vitro of several sulfated glycosaminoglycans with low density lipoproteins (LDL) has been studied. Chondroitin 6-sulfate and heparin were the only ones to produce turbidity when added to LDL in presence of Ca2+. However, when these two glycosaminoglycans were applied to LDL-affinity columns in presence of Ca2+, only chondroitin 6-sulfate was retained. Partially desulfated chondroitin 6-sulfate was not retained on LDL-affinity column, indicating the relevance of sulfate groups in the binding of LDL. Since chondroitin 4-sulfate and heparin, with a sulfate content respectively equal to and greater than that of chondroitin 6-sulfate, are not retained on LDL-affinity columns, the factors relevant to the binding of LDL are probably the conformation of the glycan in solution and the orientation of its sulfate groups.


Assuntos
Sulfatos de Condroitina/metabolismo , Condroitina/análogos & derivados , Lipoproteínas LDL/metabolismo , Cromatografia de Afinidade , Glicosaminoglicanos/metabolismo , Heparina/metabolismo , Humanos , Substâncias Macromoleculares , Peso Molecular , Nefelometria e Turbidimetria
10.
Experientia ; 37(3): 221-3, 1981 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-6263673

RESUMO

Treatment of radioactively labeled guinea-pig skin soluble collagen or calf skin collagen with the flavonoid (+)-catechin makes the collagen resistant to the action of mammalian collagenase but not to the action of bacterial collagenase. Complete resistance to the action of the mammalian enzyme may be achieved by incubating 0.6 mg of collagen (dry weight) with 0.1 mM (+)-catechin, followed by dialysis to remove the unbound flavonoid. Since incubation of the mammalian enzyme with (+)-catechin does not inhibit its activity, it is postulated that (+)-catechin binds tightly to collagen and modifies its structure sufficiently to make it resistant to enzyme degradation.


Assuntos
Benzopiranos/farmacologia , Catequina/farmacologia , Colágeno/metabolismo , Colagenase Microbiana/metabolismo , Animais , Géis , Cobaias , Humanos , Especificidade por Substrato
11.
Carbohydr Res ; 88(1): 93-105, 1981 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-6451291

RESUMO

An extract of bacterial cells Pseudomonas sp. IFO-13309 grown on medium containing 0.1% bovine cornea keratan sulfate of low sulfate content degraded exhaustively bovine cornea keratan sulfate to give 2-acetamido-2-deoxy-beta-D-gluco-pyranosyl 6-sulfate-(1 goes to 3)-D-galactose, isolated by gel filtration on Sephadex G-25 and purified by preparative paper chromatography. This was reduced with sodium borotritide to give 2-acetamido-2-deoxy-beta-D-glucopyranosyl 6-sulfate-(1 goes to 3)-D-[1-3H]galactitol, purified by gel filtration on Sephadex G-15, which was an excellent substrate for the measurement of 2-acetamido-2-deoxy-D-glucose 6-sulfate sulfatase. The reduced, radioactive monosulfated disaccharide was desulfated with methanolic 70mM hydrogen chloride and purified by gel filtration on Sephadex G-15 to give O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-(1 goes to 3)-D-[1-3H]galactitol, which allowed the measurement of (1 goes to 3)-N-acetyl-beta-D-glucosaminidase. This enzyme may participate in the normal degradation of keratan sulfate.


Assuntos
Acetilglucosaminidase/metabolismo , Glicosaminoglicanos , Hexosaminidases/metabolismo , Sulfato de Queratano , Pseudomonas/enzimologia , Sulfatases/metabolismo , Animais , Bovinos , Córnea , Dissacarídeos , Especificidade por Substrato
14.
Acta Astronaut ; 6(10): 1323-33, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11902175

RESUMO

Urinary excretion of amino acids by the 9 Skylab crewmen was studied as an indicator of the metabolic effects caused by exposure to the space flight environment. Intake was consistent in quality and quantity throughout the 28, 59 and 84-day flights for each of the crewmen and complete collections were accomplished. The results indicated an increased excretion in most amino acids during the first month of flight which remained elevated in the second and third months but to a lesser extent. Additional indications of change in muscle and skeletal metabolism were observed. These results point to the desirability of obtaining additional indices of alterations in protein synthetic processes in conjunction with future space flights.


Assuntos
Adaptação Fisiológica , Aminoácidos/metabolismo , Aminoácidos/urina , Voo Espacial , Ausência de Peso , Metabolismo Energético/fisiologia , Humanos , Hidroxilisina/análogos & derivados , Hidroxilisina/metabolismo , Hidroxilisina/urina , Hidroxiprolina/metabolismo , Hidroxiprolina/urina , Masculino , Metilistidinas/metabolismo , Metilistidinas/urina
15.
Arch Environ Health ; 34(2): 83-7, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-434936

RESUMO

Measurement of several urinary metabolites of hydroxylysine indicates that considerable collagen degradation occurred in four individuals immediately after they had inhaled concentrated ammonia vapors. Since clinical and/or radiological evidence of intense upper respiratory and pulmonary inflammation were evident, it is likely that collagen degradation occurred at the level of the respiratory system.


Assuntos
Amônia/intoxicação , Colágeno/metabolismo , Hidroxilisina/urina , Adolescente , Criança , Creatinina/urina , Exposição Ambiental , Feminino , Humanos , Hidroxilisina/metabolismo , Lactente , Masculino , Doenças Respiratórias/induzido quimicamente
17.
Circ Res ; 43(2): 234-8, 1978 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-208802

RESUMO

Formalinized, tannic acid-treated sheep erythrocytes coated with low density lipoproteins (LSL) or apoprotein B (apo-B) are are agglutinated by anti-apo-B immunserum. Those coated with high density lipoproteins (HDL) or apoprotein A-I(apo-A-I) are agglutinated by anti-apo-A-I immunserum. These coated formocells have been used to study the interactions of lipoproteins and apoproteins with plasma glycosaminoglycans (GAG). The sulfate-rich species of plasma GAG agglutinates cells coated with LDL, HDL, apo-B, and apo-A-I at ionic concentrations above 0.15 M. The less-sulfated species of plasma GAG does not agglutinate the coated cells but inhibits the agglutination caused by the sulfate-rich species. Treatment of the sulfate-rich GAG with papain causes a reduction in molecular weight by one-half and also causes a loss of its agglutinating activity. These results suggest that the sulfate-rich plasma GAG, consisting of two glycan chains linked to a peptide backbone, cause agglutination by binding to two or more formocells. In contrast, the less-sulfated plasma GAG, consisting of single, short glycan chains, are incapable of causing agglutination but may prevent it by covering specific binding sites present on the coated cells.


Assuntos
Glicosaminoglicanos/sangue , Lipoproteínas/sangue , Apoproteínas/imunologia , Testes de Hemaglutinação , Humanos , Soros Imunes/farmacologia , Lipoproteínas HDL/metabolismo , Lipoproteínas VLDL/metabolismo , Sulfatos/metabolismo
19.
Carbohydr Res ; 64: 225-35, 1978 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-98232

RESUMO

Commercially available sodium heparinate has been sequentially treated with methanolic 0.06M hydrogen chloride and nitrous acid. The nondegraded material was separated by gel filtration from the nonsulfated and monosulfated disaccharides produced. The latter ones, obtained in 10% yield, have been used as a substrate for the direct measurement of the enzyme L-iduronic acid 2-sulfate sulfatase present in human plasma and fibroblast homogenates. Studies of the kinetics and pH optimum of the enzyme, by use of plasma of a patient with mucolipidosis II, indicated an apparent Km of 2.5mM and a pH optimum of 4.6--4.8. The levels of activity in normal plasma and plasma of a patient with Hunter's disease were found to be 20.4 +/- 1.22 units (mumol sulfate/24 h/g protein) and 3.25 +/- 0.35 units, respectively. In homogenates of cultured skin fibroblasts, the levels were 137.6 +/- 10.7 units for normal controls and 6.4 +/- 5.1 for patients with Hunter's disease. The plasma two obligated heterozygotes gave intermediate levels of activity, whereas the plasma of two possible heterozygotes gave either intermediate levels or entirely normal levels of activity.


Assuntos
Heparina/metabolismo , Iduronato Sulfatase/metabolismo , Mucopolissacaridose II , Mucopolissacaridose II/enzimologia , Sulfatases/metabolismo , Dissacarídeos/metabolismo , Feminino , Fibroblastos/enzimologia , Heterozigoto , Humanos , Iduronato Sulfatase/análise , Mucopolissacaridose II/genética
20.
Science ; 199(4324): 79-81, 1978 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-17569489

RESUMO

[1-3H]Galactitol-6-sulfate, N- [1-3H]acetylgalactosaminitol-6-sulfate, N-[1-3H]acetylglucosaminitol-6-sulfate, N-acetylglucosamine-6-sulfate, and 6-sulfated tetrasaccharides from chondroitin-6-sulfate have been used for the measurement of 6-sulfatase activity of extracts of normal skin fibroblasts and of fibroblasts cultured from patients with genetic mucopolysaccharidoses. With these substrates, extracts of fibroblasts derived from Morquio patients lack or have greatly reduced activities for galactitol-6-sulfate, N-acetylgalactosaminitol-6-sulfate, and 6-sulfated tetrasaccharides but have normal activity for N-acetylglucosamine-6-sulfate and its alditol; those derived from a patient with a newly discovered mucopolysaccharidosis have greatly reduced activity for N-acetylglucosamine-6-sulfate and its alditol but normal activity for galactitol-6-sulfate, N-acetylgalactosaminitol-6-sulfate, and the 6-sulfated tetrasaccharides. These findings demonstrate the existence of two different hexosamine-6-sulfate sulfatases, specific for the glucose or galactose configuration of their substrates. Their respective deficiencies, causing inability to degrade keratan sulfate and heparan sulfate in one case and keratan sulfate and chondroitin-6-sulfate in the other, are responsible for different clinical phenotypes.


Assuntos
Condroitina Sulfatases/deficiência , Mucopolissacaridoses/enzimologia , Mucopolissacaridose IV/enzimologia , Sulfatases/deficiência , Acetilgalactosamina/análogos & derivados , Acetilgalactosamina/metabolismo , Acetilglucosamina/análogos & derivados , Acetilglucosamina/metabolismo , Células Cultivadas , Pré-Escolar , Sulfatos de Condroitina/metabolismo , Condroitina Sulfatases/metabolismo , Fibroblastos/enzimologia , Galactitol/metabolismo , Heparitina Sulfato/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Sulfato de Queratano/metabolismo , Masculino , Mucopolissacaridose III/enzimologia , Pele/citologia , Pele/enzimologia , Especificidade por Substrato , Sulfatases/metabolismo
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