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Biomedical subjects

J Solomon

Publications and source records attributed to J Solomon.

At least 73 records · Page 4Linked to original sources
PubMed1989

Inhibition of soybean lipoxygenase and mouse skin tumor promotion by onion and garlic components.

Onion and garlic essential oils were previously shown to inhibit mouse skin tumor promotion, as were the enzymes, lipoxygenase, and cyclooxygenase. In the present study, the inhibition of soybean lipoxygenase (EC 1.13.11.12) by onion and garlic components and related compounds was investigated. The IC50 values as well as the kinetic inhibition constants were determined for the most active compounds. Di-(1-propenyl) sulfide, an analog of the substrate moiety required for oxygenase action, was the only irreversible inhibitor observed with Ki = 59 microM and k3 = 0.53/min. Inhibition in the presence of substrate was uncompetitive at 88 and 132 microM linoleic acid with Ki = 129 microM. At 173 microM linoleic acid, however, inhibition was competitive with Ki = 66 microM. Dially trisulfide, allyl methyl trisulfide, and diallyl disulfide were competitive inhibitors, while 1-propenylpropyl sulfide and (E, Z)-4,5,9-trithiadodeca-1,6,11-triene 9-oxide (ajoene) were mixed inhibitors. Nordihydroguaiaretic acid (NDGA), the most potent lipoxygenase inhibitor, was a competitive inhibitor with Ki = 0.29 microM. The results indicate a relative potency of inhibition for structural features in the following order: di(1-propenyl) sulfide greater than an alkenyl trisulfide greater than an alkenyl disulfide. Di(n-propyl) disulfide, a major onion oil component, inhibited neither lipoxygenase nor promotion. Di(1-propenyl) sulfide and ajoene inhibited both. This suggests that the inhibition of lipoxygenase may be involved in antipromotion.

Allium↗
PubMed1989

A comparative study of proliferating (borderline) and invasive epithelial ovarian tumours in young women.

A series of 18 patients with proliferating or borderline ovarian tumours and 18 with invasive ovarian tumours is discussed. Proliferating tumours occurred at a younger mean age than invasive disease, and presented at an earlier stage, both contributing factors to their more favourable outlook. Histopathological assessment revealed that the majority of both proliferating and invasive tumours were of serous origin. Mucinous cell type occurred less often as did the endometrioid and clear cell types. The management of the proliferating tumours involved 'radical' surgical procedures in 11 of 18 (61.6%) patients. Only 7 patients (38.8%) had conservative surgical procedures performed. Six patients (33%) had adjuvant chemotherapy while 2 (11%) also underwent abdominopelvic irradiation. All patients with invasive disease had radical surgery and adjuvant chemotherapy and 2 also received abdominopelvic irradiation. The fact that epithelial malignancies of the ovary do occur in younger women needs to be remembered by gynaecologists contemplating surgical procedures on younger patients with adnexal masses. Proliferating or borderline tumours tend to occur more frequently in the younger age groups, and contrary to the implication of their name, they are associated with significant morbidity and mortality.

Adolescent↗
PubMed1989

Characterization of glomerular thromboxane receptor sites in the rat.

The aim of this study was to identify and characterize thromboxane (Tx) receptor sites in renal glomeruli. Binding studies were performed on freshly isolated glomeruli using the stable TxA2 receptor antagonist, [3H]SQ 29548. Specific binding was saturable, reversible, and varied with glomerular protein. Scatchard plots revealed a single class of high-affinity receptor sites (Kd = 14.3 +/- 2.4 nM, Bmax = 361 +/- 22 fmol/mg; n = 5). Specific binding was inhibited by Tx agonists (U-46619 and U-44069) and antagonist (SQ 29548) and was highly specific for Tx, since prostaglandin (PG)E2 and PGF2 alpha were 1,000-fold less potent in inhibiting binding. In vivo, U-46619 (1.75 micrograms.kg-1.min-1) was without effect on mean arterial pressure, but reduced renal blood flow by 71% (P less than 0.01) and glomerular filtration rate by 67% (P less than 0.01) and increased filtration fraction by 24% (P less than 0.05). SQ 29548 (10 micrograms.kg-1.min-1) completely blocked the renal effects of U-46619. These studies demonstrate the presence of specific receptor sites for Tx on renal glomeruli that are linked to modulation of renal hemodynamics.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1988

Carbohydrate structures of the human-immunodeficiency-virus (HIV) recombinant envelope glycoprotein gp120 produced in Chinese-hamster ovary cells.

The present paper describes the structures of the N-linked oligosaccharides of the human-immunodeficiency-virus (HIV) envelope glycoprotein gp120 (cloned from the HTLV-III B isolate and expressed as a secreted fusion protein after transfection of Chinese-hamster ovary cells), which is known to bind with high affinity to human T4-lymphocytes. Oligosaccharides were released from peptide by hydrazinolysis, fractionated by paper electrophoresis, high-performance lectin-affinity chromatography and Bio-Gel P-4 column chromatography, and their structures determined by sequential exoglycosidase digestions in conjunction with methylation analysis. The glycoprotein was found to be unique in its diversity of oligosaccharide structures. These include high-mannose type and hybrid type, as well as four categories of complex-type chains: mono-, bi-, tri- and tetra-antennary, with or without N-acetyl-lactosamine repeats, and with or without a core-region fucose residue. Among the sialidase-treated oligosaccharides, no less than 29 structures were identified as follows: (formula; see text) where G is galactose, GN is N-acetylglucosamine, M is mannose, F is fucose, and '+/- ' means that residues are present in a proportion of chains. The actual number of oligosaccharide structures is much greater, since before desialylation there was evidence that, among the hybrid and complex-type chains, all but 6% contained sialic acid at the C-3 position of terminal galactose residues, and partially sialylated forms of the bi- and multi-antennary chains were present. Detailed evidence for the proposed oligosaccharide sequences will be published as a supplementary paper [T. Mizuochi, M. W. Spellman, M. Larkin, J. Solomon, L. J. Basa & T. Feizi (1988) Biomed. Chromatogr., in the press].

Animals↗
PubMed1988

Structural characterization by chromatographic profiling of the oligosaccharides of human immunodeficiency virus (HIV) recombinant envelope glycoprotein gp120 produced in Chinese hamster ovary cells.

This report together with the paper by T. Mizuochi, M. W. Spellman, M. Larkin, J. Solomon, L. J. Basa and T. Feizi (1988) Biochem. J. 254, 599-603 describes the structural elucidation of the N-linked oligosaccharides of the HIV envelope glycoprotein, gp120 (cloned from the HTLV-III B isolate and expressed as a secreted fusion protein after transfection of Chinese hamster ovary cells), which is known to bind with high affinity to human T4 lymphocytes. Oligosaccharides were released from peptide by hydrazinolysis, fractionated by paper electrophoresis, high performance lectin affinity chromatography and Bio-Gel P-4 column chromatography, and their structures determined by sequential exoglycosidase digestions in conjunction with methylation analysis. The glycoprotein was found to be unique in its diversity of oligosaccharide structures. These include high-mannose type and hybrid type, as well as four categories of complex type chains: mono-, bi-, tri- and tetra-antennary, with or without N-acetyllactosamine repeats, and with or without a core region fucose residue. Among the sialidase-treated oligosaccharides no less than 29 structures were identified as follows: (formula; see text) where G = galactose; GN = N-acetylglucosamine; M = mannose; F = fucose; +/- = residues present in a proportion of chains. The actual number of oligosaccharide structures is much greater since before desialylation there was evidence that among the hybrid and complex type chains all but 6% contained sialic acid at the C-3 position of terminal galactose residues, and partially sialylated forms of the bi- and multiantennary chains were present.

Animals↗
PubMed1988

The role of surgical reexploration following chemotherapy in ovarian cancer.

Two hundred and eighty three patients with FIGO Stages III-IV ovarian epithelial cancer were entered on a randomized trial of chlorambucil with or without cisplatin. Eighty two of these patients have subsequently undergone surgical reexploration. Ten of these were for surgical indications (intestinal obstruction, etc.), and 7 were interval reexplorations at about 6 months on patients who had not been adequately debulked at primary surgery. The remaining 65 patients had elective operations after 12 months chemotherapy, and in 52 of these there was no pre-operative clinical evidence of residual disease. Complete Surgical Response rate (CRS) was similar in the 2 treatment arms (8% v 9.7%); 42.3% of patients in apparent remission at 12 months had negative reexploration and 57.5% of these were alive after 4 years (post-reexploration median survival greater than 4 1/2 years). The remaining 57.7% of patients had residual disease at reexploration and their 4-year survival was 15% (median survival 73 weeks). A further group of 13 patients had 'responding' and probably resectable residual disease at 12 months. These patients were reexplored with a view to secondary debulking. Their 4-year postoperation survival was 15% (median survival, 70 weeks). There were 9 patients who, though in apparent remission at 12 months, were not subjected to surgical reexploration. The median survival for this group was 33 weeks, calculated from the mean theoretical time when they should have had reexploration. This was significantly inferior to the results for the 52 patients, also in apparent remission, who underwent reexploration (4-year survival 32.5%, median survival 123 weeks, p = 0.002).

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1987

Non-infectious corneal vascularization.

A 26-year-old white female presented with a complaint of tearing and light sensitivity of several weeks duration. Examination revealed a translucent foreign body embedded in the temporal aspect of the right cornea. The fragment embedded in the cornea produced localized corneal inflammation and vascularization. The foreign body was removed and the eye was pressure patched overnight. One day after removal of the foreign body, the eye was white and quiet and the patient was comfortable. This case report represents a unique in vivo observation into the pathogenesis of non-infectious corneal vascularization.

Adult↗
PubMed1986

Early exposure to delta 9-tetrahydrocannabinol influences neuroendocrine and reproductive functions in female rats.

Sexual differentiation of the rat brain is affected by certain compounds administered during the neonatal period. We evaluated the effects of exposure to THC during the critical period of sexual differentiation of the female rat brain on postpubertal estrous cycles and brain neurotransmitter levels. Newborn female rats were injected either with vehicle (oil) or with different doses of THC (0.38; 1.9 or 3.8 mg/100 g) subcutaneously during the first 5 days after birth. The rats were examined daily by vaginal lavage smears from 3 to 10 months of life for phases of estrous cyclicity. The animals were then sacrificed and the anterior hypothalamus preoptic area (AHPOA) and medial basal hypothalami (MBH) were collected, processed and the methionine-enkephalin (met-enkephalin), beta-endorphin-like immunoreactivity (beta-end LI), LHRH and substance-P were measured by radioimmunoassays. In addition, serum LH and prolactin levels were measured by radioimmunoassay. Compared with the control rats, the rats perinatally exposed to THC exhibited either constant metestrus diestrus type vaginal smears or irregular estrous cycles. In the THC-treated animals, the met-enkephalin and beta-end LI levels were lower in the AHPOA and higher in the MBH. The LHRH levels of THC-treated rats were significantly lower in the MBH. The substance-P levels were significantly lower in the AHPOA of THC treated animals. In the THC-treated rats, serum LH was low but, the prolactin levels were not significantly different from the control animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗