Gamow-Teller transition strengths from 56Ni.

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.

Heparan sulfate degradation: relation to tumor invasive and metastatic properties of mouse B16 melanoma sublines.

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.

Deficiencies of glucosamine-6-sulfate or galactosamine-6-sulfate sulfatases are responsible for different mucopolysaccharidoses.

[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.

The glycosaminoglycans of human plasma.

A method is proposed for the measurement of glycosaminoglycans (GAG) on 5-10 ml of plasma. It is based on the adsorption of GAG on small ECTEOLA columns followed by measurement of the hexuronic acid in the NaCl eluates. Routine use of the method has indicated the presence of a GAG fraction that adsorbs readily on ECTEOLA ("free" GAG) and of another that adsorbs on it only after treatment with papain ("bound" GAG). "Free" and "bound" GAG have been measured in normal adults, normal children, and children affected by mucopolysaccharidosis type I; the results obtained are in good agreement with those previously reported in the literature.Various analyses performed on purified "free" and "bound" GAG have confirmed that chondroitin-4-sulfate is the main glycosaminoglycan of normal human plasma where it occurs both free and bound to protein and at various levels of sulfation. The presence of small amounts of heparan sulfate and keratan sulfate has also been demonstrated. Metabolic experiments performed in rabbits have indicated that plasma GAG derive from peripheral tissues and increase sharply after papain injection. In young animals the "free" GAG have a faster turnover than the "bound," possibly a reflection of active processes of remodeling and calcification. The synthesis of the "free" and "bound" GAG, as measured with (85)S-sulfate incorporation, seems to proceed at the same rate, and the hypothesis has been advanced that as a result of the action of tissue proteases, part of the "bound" GAG may be transformed into "free" GAG, the latter being immediately extruded from the tissues into the circulatory system.

N-acetylgalactosamine-6-sulfate sulfatase in man. Absence of the enzyme in Morquio disease.

Human N-acetylgalactosamine-6-sulfate sulfatase (6-sulfatase) activity is measured by using as a substrate a sulfated tetrasaccharide obtained by digesting purified chondroitin-6-sulfate (C-6-S) with testicular hyaluronidase. The amount of inorganic sulfate released is measured turbidimetrically. The enzyme from human kidney has a pH optimum of 4.8; its activity is augmented by low levels of NaCl and inhibited by phosphate and high levels of NaCl. Free glucuronate, acetylgalactosamine, inorganic sulfate, polymeric C-6-S, or tetrasaccharide obtained from chondroitin-4-sulfate do not affect the enzyme activity. The method may be used for the diagnosis of Morquio disease since extracts of Morquio fibroblasts are devoid of 6-sulfatase activity.

The binding of chondroitin 6-sulfate to plasma low density lipoprotein.

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.

Fibromyalgia syndrome in patients infected with human immunodeficiency virus. The Boston City Hospital Clinical AIDS Team.

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.

Reliability of the Booth-Nadler technique for the detection of Hunter heterozygotes.

Skin fibroblasts from three obligated and one potential heterozygotes for the Hunter gene displayed abnormal metabolism of glycosaminoglycans four to six weeks after rapid freezing in liquid nitrogen. The technique seems to be useful for the identification of Hunter carriers, especially when the degradation of 35SO4-labeled, intracellular glycosaminoglycans, rather than the uptake of 35SO4, is measured.

The urinary excretion of collagen degradation products by quadriplegic patients and during weightlessness.

Urinary total hydroxyproline, peptide-bound hydroxyproline, hydroxylysine glycosides, and calcium were measured in three healthy individuals subjected to weightlessness for eighty-four days and in three young quadriplegic patients. The former group had significant calciuria but no evidence of collagen degradation. The latter group, however, had conspicuous calciuria and also excreted large amounts of collagen breakdown products. This documented degradation of matrix may be related to the continuous calciuria, osteoporosis, and cutaneous dystrophic changes occurring in quadriplegics.

Preparation from keratin sulfate of substrates for the measurement of 2-acetamido-2-deoxy-D-glucose 6-sulfate sulfatase and (1 goes to 3)-N-acetyl-beta-D-glucosaminidase.

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.

A substrate for direct measurement of L-iduronic acid 2-sulfate sulfatase.

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.

Cleavage of the (1 goes to 3)-2-acetamido-2-deoxy-beta-D-glucopyranosyl linkage present in keratan sulfate. The A and B isoenzymes of human liver hexosaminidase (EC 3.2.1.30).

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.

Collagen breakdown and ammonia inhalation.

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.

Amino aciduria in weightlessness.

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.