Synergistic anti-tumor effects of mitomycin C and bile salts against L1210 cells

The effects of various adjuvants on the cytotoxicity of mitomycin C (MMC) were studied in L1210 mouse leukemia cells. Adjuvants examined in this study were sodium glycocholate (Na-GC), sodium deoxycholate (Na-DC), O-n-dodecyl-beta-D-maltopyranoside (LM), and sodium salicylate. Among various additives, bile salts such as Na-GC and Na-DC were the most effective for increasing the cytotoxicity of MMC against L1210 cells. A dose-dependent increase in cytotoxic effect of MMC was observed in the presence of these bile salts. To elucidate a possible mechanism for enhancing the cytotoxic effect of MMC by the bile salts, the cellular uptake of MMC with or without Na-GC was examined using L1210 cells. The cellular concentration of MMC was determined by a reversed-phase HPLC. When Na-GC was coadministered with MMC, the uptake of MMC into L1210 cells was significantly enhanced as compared with MMC alone. Furthermore, the membrane fluidity of L1210 cells, as determined by fluorescence polarization, was increased in the presence of Na-GC. These results suggested that the enhancement of cytotoxicity of MMC by the addition of Na-GC could be attributed to the increasing cellular uptake of MMC due to the increasing membrane fluidity of L1210 cells.

Demonstration of endothelin (ET) receptors on cultured rabbit chondrocytes and stimulation of DNA synthesis and calcium influx by ET-1 via its receptors

Endothelin (ET) receptors on chondrocytes were demonstrated using cultured rabbit costal chondrocytes. After crosslinking the receptors on the cells with 125I-ET-1, two major bands of 43 kDa and 46 kDa were separated by SDS-PAGE. Scatchard analysis demonstrated two classes of ET receptors with Kd values of 1 x 10(-10) M and 5 x 10(-9) M. The numbers of high- and low-affinity receptors were 1 x 10(4) and 2 x 10(5) per cell, respectively. The binding of ET-1 to chondrocytes was increased by treatment with PTH, DBcAMP, TGF-beta 1, IL-1 beta, RA and EGF. ET-1 stimulated DNA synthesis in cultured rabbit chondrocytes. ET-1 also stimulated calcium incorporation through the cell membrane of chondrocytes. These findings indicate that ET-1 has a physiological effect on chondrocytes via its receptors on the cells.

Luminal loss and site of restenosis after Palmaz-Schatz coronary stent implantation

Restenosis has frequently been observed at the articulation of the Palmaz-Schatz stent. However, the precise mechanism for this remains poorly understood. We measured the luminal diameter in 5 segments within the stent in 67 lesions of 63 patients with successful stenting. Luminal diameter at all 5 sites was significantly reduced 6 months after stent implantation (3.2 +/- 0.5 vs 2.4 +/- 0.7 mm, p < 0.05). Angiographic restenosis rate was 18%. Restenosis involving the articulation was found in 75% of the lesions, and that involving the articulation or edges in 83%. The diameter at the articulation was significantly smaller both immediately (3.0 +/- 0.5 mm vs 3.3 +/- 0.5 mm, p < 0.05) and 6 months after (2.1 +/- 0.8 mm vs 2.5 +/- 0.7 mm, p < 0.05) stenting than the diameter of other stent segments. The loss index was significantly greater at the proximal and distal edges than at the bodies of the stent (0.98 vs 0.60, p < 0.05). The edges of the Palmaz-Schatz stent tend to dilate more than the body of the stent during normal inflation. Although this anchoring system protects against dislodgment or migration of the stent, it may cause more injury. The articulation has 2 anchoring edges within only a 1 mm diameter. Thus, restenosis at the articulation may be ascribed to residual stenosis, increased intimal proliferation due to more severe injury, and delayed late vessel remodeling from lack of mechanical support. These characteristics may be attributed to stent design, and design improvement of the articulation may lead to more favorable results after stent implantation.

A warning detector for urinary incontinence for home health care

A telemetry system for monitoring urinary incontinence has been developed using two principles, temperature and impedance changes of a diaper. The system is composed of a pair of sensors, a transmitter, and a receiver. Temperature changes are monitored using thermistors, one in the center of the diaper and the other attached to the abdomen, and the temperature differences between them after urinary incontinence is detected. For the impedance method, two electroconductive cloths as electrodes placed in the diaper are used as sensors. Urine acts as a conductor to produce a current between the sensors. Clinical evaluation showed that both methods operate well; 13 of 17 incontinence episodes were detected using the temperature method and 32 of 35 with the impedance method. The misdetections were caused by faulty sensor arrangement for temperature measurement and by detection of exudates by the conductive sensors. These monitors may be used for the care of elderly people who use diapers for home health care, to save care time and help maintain hygiene.

Early and late results of repair of tetralogy of Fallot with subarterial ventricular septal defect. A comparative evaluation of tetralogy with perimembranous ventricular septal defect

Between November 1966 and December 1990, 511 pediatric patients with tetralogy of Fallot underwent corrective operation at Tenri Hospital. There were 78 patients with subarterial ventricular septal defect. Mean age at repair was 5.6 +/- 3.3 years. The method of right ventricular outflow tract reconstruction was simple infundibulectomy in 14 patients, right ventricular ventricular outflow patch in 36, and transannular patch in 28. There were 7 (9.0%) early deaths as a result of low cardiac output syndrome and acute renal failure. The pressure ratio of the right ventricle to the left ventricle was 0.62 +/- 0.18 during the early postoperative catheterization. Follow-up was achieved for 442.6 patient-years and ranged from 0.5 to 27 years, with an average of 8.5 +/- 6.7 years. There were three late deaths (2 cardiac and 1 noncardiac). Actuarial survival was 94.8% +/- 4.0% at 20 years. Catheterization during late follow-up (6.8 +/- 4.7 years after repair) was done in 53 patients and the pressure ratio of the right ventricle to the left ventricle was 0.48 +/- 0.21. Fifteen patients underwent subsequent operation because of residual lesions, including ventricular septal defect in four patients, pulmonary stenosis in nine, combined ventricular septal defect and pulmonary stenosis in one, and pulmonary regurgitation in one, with no mortality. Actuarial rate of freedom from reoperation was 71.1% +/- 8.0% at 10 years and 58.8% +/- 16.8% at 20 years. Patients with tetralogy and subarterial ventricular septal defect were more likely to have the development of residual obstruction at the level of the pulmonary valve anulus after repair than were those with tetralogy and perimembranous ventricular septal defect.

The first characterization of a eubacterial proteasome: the 20S complex of Rhodococcus

BACKGROUND

The 26S proteasome is the central protease of the ubiquitin-dependent pathway of protein degradation. The proteolytic core of the complex is formed by the 20S proteasome, a cylinder-shaped particle that in archaebacteria contains two different subunits (alpha and beta) and in eukaryotes contains fourteen different subunits (seven of the alpha-type and seven of the beta-type).

RESULTS

We have purified a 20S proteasome complex from the nocardioform actinomycete Rhodococcus sp. strain NI86/21. The complex has an apparent relative molecular mass of 690 kD, and efficiently degrades the chymotryptic substrate Suc-Leu-Leu-Val-Tyr-AMC in the presence or absence of 0.05% SDS. Purified preparations reveal the existence of four subunits, two of the alpha-type and two of the beta-type, the genes for which we have cloned and sequenced. Electron micrographs show that the complex has the four-ringed, cylinder-shaped appearance typical of proteasomes.

CONCLUSIONS

The recent description of the first eubacterial ubiquitin, and our discovery of a eubacterial proteasome show that the ubiquitin pathway of protein degradation is ancestral and common to all forms of life.

Monitoring urine oxygen tension during acute change in cardiac output in dogs

To evaluate whether renal blood flow (RBF) can be monitored during acute change in cardiac index, ureter urine oxygen tension (PuO2) and bladder urine oxygen tension (PbO2) were measured in six mongrel dogs. PuO2, cardiac index, and RBF increased after dobutamine infusion and decreased after propranolol infusion. PuO2 had an excellent correlation with RBF (r = 0.94) and a fair correlation with cardiac index (r = 0.50) and mean blood pressure (r = 0.56); RBF had a fair correlation with mean blood pressure (r = 0.52, P < 0.05) but was not related to cardiac index. With multiple-regression analysis, PuO2 was found to be the significant factor related to RBF. PbO2 had a good correlation with PuO2 (r = 0.94) at control levels. Furthermore, when two dogs were added to evaluate relationships among PbO2, PuO2, and RBF, PbO2 had an excellent correlation with PuO2 (r = 0.92) and RBF (r = 0.91). These data indicate that PuO2 is a more sensitive predictor of RBF than cardiac index and mean blood pressure and that PbO2 can be a noninvasive indicator reflecting RBF during acute circulatory change in dogs.

Elastic recoil following percutaneous transluminal coronary angioplasty and Palmaz-Schatz stent implantation

The post-procedural elastic recoil in 133 lesions treated with the Palmaz-Schatz stent was compared to 133 matched lesions treated with balloon angioplasty to determine the role of prevention of elastic recoil in the creation of a larger initial luminal diameter. Elastic recoil was defined as the difference between the maximal diameter of the inflated balloon and the minimal luminal diameter of the dilated segment immediately after the procedure and was evaluated by quantitative coronary angiography. Overdilatation was defined as a dilatation induced by a balloon with a maximal diameter larger than the pre-procedure reference diameter. The percent diameter stenosis was reduced from 73% to 31% in the balloon angioplasty group and from 72% to -4% in the stent group (31% vs. -4%, p < 0.01). Elastic recoil was significantly larger in the balloon angioplasty group than in the stent group (0.94 +/- 0.29 mm vs. 0.09 +/- 0.09 mm, p < 0.01). Overdilatation and lesion morphology had no significant effects on elastic recoil in the stent group. In the balloon angioplasty group, overdilatation, noncalcified lesions and eccentric lesions were associated with increased elastic recoil. These results indicated that the larger post-procedural luminal diameter associated with the Palmaz-Schatz stent was primarily the result of prevention of elastic recoil, which was not influenced by the degree of overdilatation or lesion morphology.

Correlation of therapeutic outcome in non-small cell lung cancer and DNA damage assayed by polymerase chain reaction in leukocytes damaged in vitro

A pilot study was conducted in patients with advanced non-small cell lung cancer to examine whether the gene-specific damage in mononuclear cells (MNCs) incubated with cisplatin in vitro correlates with chemotherapeutic outcome in cisplatin-based chemotherapy. Twenty-one patients received cisplatin-based chemotherapy, consisting of cisplatin (80 mg/m2 i.v. on day 1), vindesine (3 mg/m2 i.v. on days 1 and 8), with or without mitomycin (8 mg/m2 i.v. on day 1). MNCs from peripheral blood were obtained from each patient before chemotherapy. The cells were incubated with cisplatin for 3 h in vitro and the 2.7-kb fragment of the hypoxanthine phosphoribosyltransferase gene was amplified by PCR for quantitation of DNA damage. There was a 4-fold interpatient variation in DNA damage in MNCs. Seven of 21 patients had a partial response to chemotherapy. When the dose of cisplatin required to reduce amplification of the hypoxanthine phosphoribosyltransferase sequence by 63% (D63 value) of MNCs was compared in each patient (defined by a Poisson distribution as the dose that produced an average of one lesion per single strand of the 2.7-kb fragment), the mean D63 value in patients showing a partial response (n = 7; 52 +/- 11 micrograms/ml) was significantly lower than that in patients showing no change (n = 10; 81 +/- 20 micrograms/ml; P = 0.0045) and in patients with disease progression (n = 4; 115 +/- 34 micrograms/ml; P = 0.0012). The mean D63 in patients with no change was also significantly lower than that in the patients with disease progression (P = 0.0386). Seven (70%) of 10 patients with a D63 value < 70 micrograms/ml were responders. No relationship was observed between the D63 values and hematological and nonhematological toxicities. It is suggested that DNA damage in MNCs incubated by cisplatin treatment in vitro in responders was greater than that in nonresponders. Gene-specific damage in MNCs from peripheral blood incubated with cisplatin in vitro assayed by PCR may predict the chemotherapeutic response in cisplatin-based chemotherapy for non-small cell lung cancer.

Gene expression of liver-specific proteins in hepatocyte spheroids in primary culture

Adult rat hepatocytes assemble to form multicellular spheroids under non-adherent environments such as immobilized chondroitin sulfate-proteoglycan in primary culture. Previously, we demonstrated that hepatocyte spheroids exhibited various differentiated structures as observed in the liver tissue. It was also shown that hepatocyte growth was highly suppressed and several differentiated functions, including albumin production and gluconeogenesis, were well preserved in spheroids. To investigate the differentiated functions of cultured hepatocytes in relation to cell morphology, we compared the expression of the albumin and transferrin genes in spheroids with those in monolayers by Northern blot analysis. Production of these proteins in the culture medium was simultaneously examined by ELISA. Gene expression and protein production of both albumin and transferrin were better preserved in spheroids. We also examined changes in the expression of liver-specific genes in response to IL-6. Reduced mRNA levels of both albumin and transferrin was only found in spheroids and no change was observed in monolayers. These results suggest that the regulation of tissue-specific gene expression is better preserved in spheroids, in which hepatocytes are in close contact with each other.

Short-term outcome and long-term follow-up of percutaneous coronary intervention in patients aged 40 years or younger

Forty five patients aged 40 years or younger were treated with coronary intervention in our institution between 1983 and 1994. This young Japanese population had a strong predisposition to risk factors but did not have extensive disease. These patients underwent 50 elective interventional procedures for angina pectoris or old myocardial infarction and 6 direct balloon angioplasty procedures for acute myocardial infarction. The initial successful result was obtained in 41 of the 45 patients (91%). The mean follow-up was 43 +/- 35 months. Angiographic follow-up was available in 31 of the 41 eligible patients (76%). Angiographic restenosis was seen in 9 of these 31 patients (29%), and in 12 of the 38 lesions (32%) with initial successful intervention. There were no deaths among the successfully treated patients. Event-free survival rate without death, myocardial infarction, or coronary artery bypass surgery was 94%; however, event-free survival rate without death, myocardial infarction, coronary artery bypass surgery, or repeat intervention was 66% at 43 months. Ninety three percent of the eligible patients were free from angina at follow-up. These short- and long-term results suggest that young Japanese patients can be treated safely and effectively with coronary interventions.

Efficient sampling strategies for forecasting pharmacokinetic parameters of irinotecan (CPT-11): implication for area under the concentration-time curve monitoring

A linear two-compartment Bayesian pharmacokinetic model was developed using a standard two-stage population method for the novel anti-cancer agent CPT-11 from 11 adult patients with refractory cancer. The accuracy and efficiency of this Bayesian model for estimating pharmacokinetic parameters including the area under the concentration-time curve (AUC) was then evaluated using two different sampling strategies in a new study cohort of 13 patients with cancer. Sampling strategies included either one, two, or three nonsteady-state feedback levels determined empirically and from optimal sampling theory (D-optimality). All 24 patients in this study received CPT-11 (60 mg/m2) as a 90-min infusion. Pharmacokinetic parameters derived from the Bayesian model combined with these limited sampling strategies were compared with those parameters obtained from the full sample data sets (n = 10) analyzed by weighted nonlinear least squares regression (reference method). The least-bias and most precise sampling times for estimating AUC were 3.5; 3.5 and 9.5; and 0.5, 3.5, and 9.5 h, respectively. At these times, only marginal improvement in precision of the AUC estimate was observed using two versus three samples. However, the precision of the estimate of clearance was not improved using two versus three samples. The sampling times derived from optimal sampling theory were 0.25, 3.5, 8.5, and 24 h and correlated closely to the actual and best empirical sampling times of 0.5, 3.5, 9.5, and 24 h. These results strongly suggest that Bayesian estimation combined with only two optimally timed samples accurately predicts the AUC of CPT-11 and should be useful for implementing adaptive control dosing for monitoring CPT-11 systemic exposure in patients with cancer.

Myocardial damage after successful thrombolysis is associated with the duration of ST re-elevation at reperfusion

The purpose of this study was to investigate the significance of ST re-elevation at reperfusion using strict criteria for patient inclusion and exclusion. Twenty-nine patients who had a first anterior infarction with single-vessel disease, successful recanalization by intracoronary thrombolysis (ICT) with urokinase, and an angiographically confirmed patent infarct-related artery after 4 weeks, were divided into three groups according to the deviation of the ST segment at reperfusion: Group A, 10 patients with sustained ST re-elevation; Group B, 10 patients with transient ST re-elevation; and Group C, 9 patients with ST reduction. Left ventricular (LV) function was evaluated from cineventriculograms performed in the 30 degrees right anterior projection 4 weeks after ICT. LV ejection fraction and regional wall motion of the infarct area, evaluated by the centerline method (SD/chords), were significantly lower in Group A (44 +/- 10%, -3.2 +/- 0.4) than in Group B (61 +/- 9%, -1.9 +/- 0.7) and Group C (60 +/- 5%, -2.0 +/- 0.4) (p < 0.01). Peak creatine kinase (CK) activity was significantly higher in Group A (5848 +/- 2112 IU) than in Group B (2485 +/- 1254 IU) and Group C (1889 +/- 1525 IU) (p < 0.05). These data suggest that a sustained ST re-elevation at reperfusion was strongly associated with marked LV dysfunction and higher peak CK activity. It was concluded that sustained, not transient, ST re-elevation associated with successful reperfusion indicates extensive myocardial damage.

Clinical pharmacokinetics and pharmacodynamics of paclitaxel: a 3-hour infusion versus a 24-hour infusion

The present study was conducted to compare the pharmacokinetics and pharmacodynamics (PD) of paclitaxel between Phase I trials of 3- and 24-h infusions and to determine the most informative pharmacokinetic parameter to describe the PD. Twenty-seven patients were treated in a Phase I study of paclitaxel by a 3-h infusion at one of six doses: 105, 135, 180, 210, 240, and 270 mg/m2. Pharmacokinetic data were obtained from all patients. Paclitaxel concentrations were measured in the plasma and urine using HPLC. The pharmacokinetics and PD were compared with those of a Phase I trial of paclitaxel by a 24-h schedule previously performed. The maximum tolerated dose of paclitaxel by a 3-h infusion was determined to be 240 mg/m2. The major toxicities were granulocytopenia, neuromuscular toxicities, and hypotension. Apparent differences in pharmacodynamic relationships for the change in granulocytes with dose, peak concentration, and areas under the concentration versus time curve were observed between the 3- and 24-h schedules. However, the relationship between the duration of plasma concentration above 0.05 microM and the change in granulocytes could be fitted to the same sigmoid maximum effect model in either schedule (P < 0.01). There were no clear relationships between peripheral neuropathy or hypotension and any pharmacokinetic parameters. The pharmacokinetics and PD of paclitaxel were schedule dependent. The duration of plasma concentration above 0.05 microM could be a common pharmacokinetic parameter predicting granulocytopenia for both schedules.

Effects of endurance training on gene expression of insulin signal transduction pathway

Alternative splicing of insulin receptor mRNA and gene expression of insulin receptor, IRS-1 and MAP kinase isoforms were examined in skeletal muscle of trained and sedentary rats. Adult male Sprague-Dawley rats were trained for 9 weeks on a treadmill: 30 m/min at 6 degrees incline, 90 min/day, 5 days/week. Endurance training increased insulin receptor mRNA level without change in alternative splicing of insulin receptor mRNA in skeletal muscle. The levels of IRS-1 and MAP kinase (ERKI) mRNA were significantly higher in trained rats than sedentary rats. Our findings provide the first evidence that gene expression of insulin receptor and postreceptor signal transduction pathway is enhanced by endurance training, without affecting alternative splicing of insulin receptor isoforms.

[Videofluorographic analysis of the swallowing disorders in spinocerebellar degeneration]

Clinical and videofluorographic (VF) studies of swallowing were performed in 11 patients with spinocerebellar degeneration (SCD). Eight patients had a subjective symptom of dysphagia. In VF study, seven patients represented abnormal findings in an oral phase such as residue on the tongue (2 patients), reduced tongue control (3 patients), uncontrolled bolus or premature loss of liquid (6 patients), and piecemeal deglutition (4 patients). Seven patients showed abnormality in a pharyngeal phase such as vallecular residue after swallow (5 patients), residue in pyriform sinuses after swallow (4 patients), delayed onset of laryngeal elevation (5 patients), and aspiration during swallow (5 patients). Aspiration was more obvious when barium liquid was swallowed. When the patients aspirated, techniques such as the chin down posture and the supraglottic swallow were tried in 4 of the 5 patients with the evidence of aspiration. The aspiration was prevented in 2 patients. It was suggested that in SCD the change in the form and volume of food is recommended for prevention of aspiration and that the rehabilitation techniques such as the chin down posture and the supraglottic swallow may also improve the dysphagia.

Synthesis and structure-activity studies of a series of 1-oxa-8-azaspiro[4.5]decanes as M1 muscarinic agonists

2,8-Dimethyl-1-oxa-8-azaspiro[4,5]decan-3-one (17), designed by incorporating the tetrahydrofuran ring moiety of muscarone into an 8-azaspiro[4,5]decane skeleton, and related 1-oxa-8-azaspiro[4.5]decanes were synthesized and assessed as M1 muscarinic agonists for the symptomatic treatment of dementia of Alzheimer's type. The compounds were tested for central muscarinic M1 and M2 receptor affinity and in vivo muscarinic activities: namely, amelioration of scopolamine-induced impairment in rat passive avoidance tasks, and induction of hypothermia, tremor, and salivary secretion. Compound 17 exhibited potent muscarinic activities in vitro and in vivo with no selectivity. Systematic modifications of 17 were conducted, and a number of compounds, including the 2-ethyl analogue (18), 3-methylene analogue (29), 3-dithioketal analogues (26, 28), and 3-oxime analogue (37) were found to display preferential affinity for M1 receptors over M2 receptors and, in addition, to exhibit potent antiamnesic activity sufficiently separated from hypothermia-inducing activity, taken as an index of cholinergic side effects, compared with the reference compound RS86 (1). Structure-activity relationships are discussed in comparison with those for muscarone analogues. Of these compounds only two, 2-ethyl-8-methyl-1-oxa-8-azaspiro[4.5]decan-3-one (18) and 2,8-dimethyl-3-methylene-1-oxa-8-azaspiro[4.5]decane (29), stimulated phosphoinositide hydrolysis in rat hippocampal slices, indicating partial agonistic activity for M1 muscarinic receptors. The optical resolution of 18 and 29 was performed. Eudismic ratios of both compounds in binding affinity were low, but M1 agonist activity resided preferentially in the (-)-isomers. The absolute configuration of (-)-29 was determined by X-ray crystal structure analysis to be S, being the same as that of muscarone. Based on the in vivo selectivity, (-)-29 was selected for clinical studies.

Synthesis of fluoroacetate from fluoride, glycerol, and beta-hydroxypyruvate by Streptomyces cattleya

Streptomyces cattleya produces fluoroacetate and 4-fluorothreonine from inorganic fluoride added to the culture broth. We have shown by 19F nuclear magnetic resonance (NMR) spectrometry that fluoroacetate is accumulated first in the culture broth and that accumulation of 4-fluorothreonine is next. To show precursors of the carbon skeleton of fluoroacetate, we carried out tracer experiments with various 14C- and 13C-labeled compounds. Radioactivity of [U-14C]glucose, [U-14C]glycerol, [U-14C]serine, and [U-14C]beta-hydroxypyruvate was incorporated into fluoroacetate to an extent of 0.2 to 0.4%, whereas [3-14C]pyruvate, [2,3-14C]succinate, and [U-14C]aspartate were less efficiently incorporated (0.04 to 0.08%). The addition of [2-13C]glycerol to the mycelium suspension of Streptomyces cattleya caused exclusive enrichment of the carboxyl carbon of fluoroacetate with 13C; about 40% of carboxyl carbon of fluoroacetate was labeled with 13C. We studied the radioactivity incorporation of [3-14C]-, [U-14C]-, and [1-14C]beta-hydroxypyruvates to show that C-2 and C-3 of beta-hydroxypyruvate are exclusively converted to the carbon skeleton of fluoroacetate. These results suggest that the carbon skeleton of fluoroacetate derives from C-1 and C-2 of glycerol through beta-hydroxypyruvate, whose hydroxyl group is eventually replaced by fluoride.

1H NMR characterization of a hen ovalbumin tyrosinamide N-linked oligosaccharide library

A library of 15 N-linked oligosaccharide structures was prepared from ovalbumin and characterized using high-field NMR and mass spectrometry. The oligosaccharides were enzymatically released from ovalbumin glycopeptides, and the reducing ends were reacted with ammonium bicarbonate to form oligosaccharide-glycosylamines. These reacted with Boc-tyrosine-N-hydroxysuccinimide ester, resulting in a mixture of tyrosinamide-oligosaccharides. The Boc group was removed to expose an amine terminus which enhanced the resolution of tyrosinamide-oligosaccharides when chromatographed on reverse-phase HPLC. Ten major and five minor oligosaccharides were purified on a micromole scale and characterized using 1H NMR and FAB-MS. The structures include high-mannose, hybrid, and complex oligosaccharides possessing from two to five antenna, providing the most complete definition of ovalbumin N-linked oligosaccharides to date. The resulting library is well suited to biological studies due to the presence of a single terminal tyrosine residue on each oligosaccharide that allows radioiodination or the attachment of additional probes to these glycoconjugates prior to biological studies.