Biomedical subjects

K Suyama

Publications and source records attributed to K Suyama.

At least 55 records · Page 3Linked to original sources

PubMed2000

Mesangial factor V expression colocalized with fibrin deposition in IgA nephropathy.

BACKGROUND: Factor V in its active form (Va) plays a key role at the termination of the intrinsic coagulation pathway, serving as a membrane-bound cofactor for the conversion of prothrombin to thrombin by factor Xa. Cross-linked fibrin (XFb) is often observed in mesangial areas in active types of human glomerulonephritis. In this study, to clarify contribution of factor V in intramesangial coagulation, mesangial factor V expression and its relationship to mesangial proliferation and fibrin deposition in IgA nephropathy (IgAN) were investigated. METHODS: Twenty-two patients with IgAN were studied. XFb was detected in renal biopsy specimens using anti-d-dimer antibody combined with plasmin exposure, and factor V was detected with rabbit antibody against human factor V. Double-labeling immunohistochemistry was used to investigate the relationship of the glomerular distribution of factor V to XFb. The relationship of factor V staining to the activity index or XFb deposition was evaluated. The expression of factor V mRNA was assessed by in situ hybridization in relationship to the antigen staining of alpha-smooth muscle actin (alpha-SMA). The ultrastructural distribution of factor V in glomeruli was studied by immunoelectron microscopy. RESULTS: XFb and factor V were observed in the mesangium and along capillary loops in seven and nine specimens, respectively. Factor V had intense, frequent expression in the proliferating and necrotizing areas, showing a significant relationship to XFb (P < 0.05). Furthermore, XFb deposition and factor V expression were markedly correlated with disease activity (P = 0.005 and P = 0.008, respectively). By double-labeling experiments, XFb and factor V were often seen colocalized in mesangial areas of the glomeruli, which showed necrotizing lesions and/or intense cellular proliferation. By in situ hybridization, factor V mRNA was detected mainly in the mesangial cells, which were positive for alpha-SMA, and partly in the endothelial cells. By immunoelectron microscopy, factor V presence was confirmed in the mesangium and endothelium. CONCLUSION: The present findings suggest that factor V is strongly expressed in mesangial cells in active IgAN accompanied with mesangial proliferation and may exert procoagulant activity, leading to intramesangial coagulation.

Actins↗

PubMed2000

Expression of Rh30 and Rh-related glycoproteins during erythroid differentiation in a two-phase liquid culture system.

BACKGROUND: To gain insight into the formation of the Rh complex during erythroid differentiation, the ways in which Rh30 and Rh-related glycoproteins, especially Rh50, were produced in a modified two-phase liquid culture system were studied. STUDY DESIGN AND METHODS: A mononuclear cell fraction from fresh peripheral blood was first cultured in a medium supplemented with conditioned medium collected from the culture of a bladder carcinoma cell line (5637) for 7 days. Nonadherent cells were then collected for culture in a secondary medium containing 2 U per mL of erythropoietin to initiate erythroid differentiation. The expression of Rh30 and Rh50 during secondary culture (16 days) was monitored by flow cytometry. RESULTS: D+ cells appeared after Day 4 and increased to 70 percent by Day 8. On Day 12, 90 percent of the total cells became D+ and remained so until the end of the culture. A similar expression profile was obtained for Rh50. As determined from mean fluorescence intensities recorded in flow cytometry, the number of both D and Rh50 antigenic sites per cell increased as the differentiation progressed. Rh-related glycoprotein, CD47, had expression patterns significantly different from those of Rh30 and Rh50. In addition, the cultured cells produced partially glycosylated protein (approx. 32 kDa) in Rh50. CONCLUSION: Expressions of Rh30 and Rh50 occur simultaneously during erythroid differentiation, and both proteins are most actively synthesized at the last stage of the differentiation. In contrast, CD47 may be involved in expression of Rh30 in a different manner from Rh50. The two-phase liquid culture system will be an excellent model for studying the interaction among the components of the Rh complex during protein synthesis and complex assembly on the cell membrane.

Anion Exchange Protein 1, Erythrocyte↗

PubMed2000

Effect of sodium channel blockers on ST segment, QRS duration, and corrected QT interval in patients with Brugada syndrome.

INTRODUCTION: Brugada syndrome is characterized by an ST segment elevation in leads V1-V3 and a high incidence of ventricular fibrillation (VF). A mutation in a cardiac Na+ channel gene, SCN5A, has been linked to Brugada syndrome, and sodium channel blockers have been shown to be effective in unmasking the syndrome when concealed. The aim of this study was to examine the effects of Na+ channel blockers on ST segment elevation, QRS, corrected QT (QTc) interval, and ventricular arrhythmias in patients with Brugada syndrome. METHODS AND RESULTS: We examined the effects of three different Na+ channel blockers (flecainide, disopyramide, and mexiletine) on the amplitude of the ST segment 20 msec after the end of QRS (ST20), QRS duration, QTc interval measured from 12-lead ECG, and ventricular arrhythmias in 12 Brugada and 10 control patients. Maximum ST20 observed in the V2 or V3 leads under baseline conditions was greater in the Brugada patients than in control patients, whereas QRS duration and maximum QTc interval were no different between the two groups. Flecainide and disopyramide, but not mexiletine, significantly increased maximum ST20 and QRS duration in both groups, although these effects were much more pronounced in the Brugada patients. The increases in ST20 and QRS duration with flecainide were significantly larger than those with disopyramide. An increase of 0.15 mV in ST20 with flecainide separated the two groups without overlap. Ventricular premature complexes developed only with flecainide in Brugada patients (3/12) displaying a marked ST elevation but not widening of QRS. CONCLUSION: Our findings suggest that Na+ channel blockers amplify existing I(Na) and possibly other ion channel defects, with a potency inversely proportional to the rate of dissociation of the drug from the Na+ channel, thus causing a prominent elevation of the ST segment and, in some cases, prolongation of QRS duration in patients with Brugada syndrome.

Adult↗

PubMed2000

Clinical characteristics of patients with spontaneous or inducible ventricular fibrillation without apparent heart disease presenting with J wave and ST segment elevation in inferior leads.

INTRODUCTION: The clinical characteristics of three patients with spontaneous or inducible ventricular fibrillation (VF) without apparent heart disease, who presented with J wave and ST segment elevation in inferior leads, are described. METHODS AND RESULTS: All patients were male and experienced syncope. Their symptoms occurred at night or early in the morning. Holter ECG revealed infrequent premature ventricular complexes. Injection with disopyramide 2 mg/kg augmented ST segment elevation. CONCLUSION: These characteristics were very similar to those of patients with Brugada syndrome. These three patients with these specific features might have a variant of Brugada syndrome.

Adult↗

PubMed2000

Recovery time dispersion measured from 87-lead body surface potential mapping as a predictor of sustained ventricular tachycardia in patients with idiopathic dilated cardiomyopathy.

INTRODUCTION: The clinical usefulness of QT dispersion in 12-lead ECG has been controversial in identifying subjects at risk for sustained ventricular tachycardia (VT) in patients with idiopathic dilated cardiomyopathy (DCM). We hypothesized that increasing the spatial resolution of the ECG improves the accuracy of risk stratification. The purpose of this study was to test the ability of recovery time dispersion measured from 87-lead body surface potential mapping (BSPM) to identify patients at risk for sustained VT in idiopathic DCM. METHODS AND RESULTS: We obtained 87-lead BSPM and 12-lead ECG in 33 patients with idiopathic DCM (15 patients with a history of sustained VT [VT(+) group] and 18 patients without a history of sustained VT [VT(-) group]) and in 20 normal control subjects. We measured the corrected QT dispersion and corrected recovery time dispersion from 12-lead ECG (QTc-12 dispersion and RTc-12 dispersion, respectively) and 87-lead BSPM (QTc-87 dispersion and RTc-87 dispersion, respectively). Signal-averaged ECG also was recorded in 25 patients. Neither the QTc-12 nor QTc-87 dispersion discriminated between the VT(+) and VT(-) groups patients. The VT(+) group patients had a larger but insignificant RTc-12 dispersion than the VT(-) group patients. In contrast, the RTc-87 dispersion was significantly larger in the VT(+) group patients than in the VT(-) group patients (236 +/- 39 msec vs 184 +/- 28 msec, P < 0.001). Receiver operating curve analysis indicated that the RTc-87 dispersion was as good as late potentials in predicting susceptibility to sustained VT; its sensitivity, specificity, and negative predictive value were 73%, 76%, and 76%, respectively (cutoff value 200 msec). RTc-87 dispersion >200 msec combined with positive late potentials provide high sensitivity (92%) and high negative predictive value (88%) for sustained VT. CONCLUSION: The RTc-87 dispersion is a useful tool to identify subjects at risk for sustained VT in patients with idiopathic DCM.

Body Surface Potential Mapping↗

PubMed2000

Body surface distribution and response to drugs of ST segment elevation in Brugada syndrome: clinical implication of eighty-seven-lead body surface potential mapping and its application to twelve-lead electrocardiograms.

INTRODUCTION: Body surface distribution and magnitude of ST segment elevation and their reflection in 12-lead ECGs have not been clarified in Brugada syndrome. METHODS AND RESULTS: Eighty-seven-lead body surface potential mapping and 12-lead ECGs were recorded simultaneously in 25 patients with Brugada syndrome and 40 control patients. The amplitude of the ST segment 20 msec after the end of QRS (ST20) was measured from all 87 leads, and an ST isopotential map was constructed. The maximum ST elevation (maxST20) was distributed in an area of the right ventricular outflow tract in all Brugada patients, and it was larger than that in control patients (0.37 +/- 0.13 vs 0.12 +/- 0.04 mV; P < 0.0005). The maximum was observed on the level of the parasternal fourth intercostal space, on which the V1 and V2 leads of the standard 12-lead ECG were located, in 18 of the 25 Brugada patients in whom typical coved- or saddleback-type ST elevation was seen in leads V1 and V2. The maximum was located on the second intercostal space in the remaining seven Brugada patients in whom only a mild saddleback-type ST elevation was seen in leads V1 and V2 of the 12-lead ECG. Typical ST segment elevation was recognized in leads V1 and V2, which were recorded on the second or third intercostal space. ST elevation in Brugada patients was dramatically normalized by isoproterenol, a beta-adrenergic agonist (maxST20 = 0.17 +/- 0.08 mV; P < 0.0005 vs control conditions), and accentuated by disopyramide, an Na+ channel blocker (maxST20 = 0.50 +/- 0.15 mV; P < 0.0005 vs control conditions), without any change in the location of the maxST20. CONCLUSION: Our data indicate that recordings of leads V1-V3 of the 12-lead ECG on the parasternal second or third intercostal space would be helpful in diagnosing suspected patients with Brugada syndrome. The data suggest that Na+ channel blockers are capable of accentuating ST elevation in leads V1-V3.

Action Potentials↗

PubMed2000

Significant suppressive effect of low-dose temocapril, an ACE inhibitor with biliary excretion, on FGS lesions in hypertensive rats.

To investigate how the interruption of the renin-angiotensin system (RAS) and reduction of blood pressure (BP) affect the lesions of chronic focal and segmental glomerulosclerosis (FGS), we studied the effects of high and low doses of angiotensin-converting enzyme inhibitors (temocapril - TEM) a newly developed ACE inhibitor with biliary tract excretion, on the hypertensive model of FGS. A high dose of TEM significantly lowered BP and suppressed both intense proteinuria and glomerular extracapillary lesions including macrophage infiltration. On the other hand, although a low dose of TEM did not significantly lower BP throughout the experimental period, it prevented renal lesions almost in the same manner as high-dose TEM with suppression of c-myc gene expression in glomeruli. These findings suggest that in PAN-induced chronic FGS, the systemic BP elevation could not be the major factor for the progression of renal damage which TEM could prevent without significant lowering of BP.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed2000

Occlusion of transition metal ions by new adsorbents synthesized from plant polyphenols and animal fibrous proteins.

Removing and collecting heavy and rare metal ions from industrial effluents and waste aqueous solutions are important problems. Our previous studies showed that animal fibrous proteins (AFPs) such as hen eggshell membrane, chicken feather (CF), wool, and silk were stable and insoluble proteins and had an excellent ability to bind not only hard (Mn2+ and Fe3+) but also soft (Ag+, Au+, Pd2+, Pt2+, and Hg2+) acids from aqueous solutions. In this study, we synthesized some adsorbents for transition (Cr6+, Mn2+, Co2+, Ni2+, and Cu2+) and heavy (Cd2+) metal ions from AFPs (gelatin, CF, and wool) and plant polyphenols (lignin and tannin) by heating a mixture of AFPs and plant polyphenols under acidic conditions. In batch experiments, pH profile, time dependency, and isotherm analysis were performed to determine binding properties of adsorbents for transition and heavy metal ions. Column experiments were also performed to remove copper ion from aqueous solution. The results showed that the new adsorbents were effective for collecting and removing transition and heavy metal ions from aqueous solutions.

Animals↗

PubMed2000

Octreotide improved ventricular arrhythmia in an acromegalic patient.

We saw a remarkable effect of octreotide, the long-acting somatostatin analogue, in reducing the number of ventricular premature complexes (VPCs) in a 59-year-old woman with acromegaly. Her basal GH and IGF-1 levels were up to 22.9 ng/ml and 934.9 ng/ml respectively. MRI revealed a 14 x 12 x 10 mm mass lesion in the pituitary gland. She had hypertension and echocardiography showed an increase in left ventricular wall thickness. Electric cardiography showed the presence of frequent VPCs and 24-h Holter monitoring revealed 24,277 beats of multifocal VPCs/24 h. She was treated with 300 microg/day of octreotide for four weeks before transsphenoidal surgery. After octreotide treatment, GH and IGF-1 were suppressed to 1.8 ng/ml and 145.3 ng/ml respectively, and the tumor size was remarkably reduced. Furthermore, the number of VPCs was also dramatically reduced to 2062 VPCs/24-h (8.5% of pretreatment) with 24-h Holter monitoring. This case shows that VPCs of acromegalic patients can be controlled by suppressing GH and IGF-1 with octreotide, and this agent is useful for reducing both tumor size and frequency of VPCs prior to surgery.

Acromegaly↗

PubMed2000

Mechanism of formation of elastin crosslinks.

We examined the formation of quaternary pyridinium crosslinks of elastin formed by condensation of lysine and allysine residues using the model compounds propanal (allysine) and n-butylamine (lysine) under quasi-physiological conditions. The resulting pyridinium compounds were characterized and the structure compared with the known pyridinium crosslinks. Three pyridinium compounds were identified and the structures were identical with the skeleton of the crosslinking amino acids, desmosine (DES), isodesmosine (IDE), and pentasine. We concluded that a non-enzymatic pathway is available for the spontaneous generation of pyridinium crosslinks. To elucidate the intermediates and the mechanism of the formation of DES and IDE, we synthesized model intermediates from propanal and n-butylamine, and they were allowed to react in three kinds of solvents. Then, the products were analyzed by an ion-pair reverse-phase HPLC. The results of this model system indicated that DES and IDE can be formed by condensation of dehydromerodesmosine with dehydrolysinonorleucine and by condensation of allysine with dehydrolysinonorleucine, respectively. We also describe the mechanism of DES and IDE crosslinking.

2-Aminoadipic Acid↗

PubMed2000

[Two cases of primary carcinoma developed in a vesical diverticulum treated with ileal neobladder for total bladder replacement].

Two cases of carcinoma developed in vesical diverticulum were encountered. Both these males, the first, 66-year-old and the second case, 68-year-old gentleman, visited our clinic with a complaint of asymptomatic gross hematuria. Total cystectomy was performed, and an ileal neobladder was constructed for total bladder replacement in both two cases. Pathological examination of the first case revealed transitional cell carcinoma, and the second case showed adenocarcinoma mixed with transitional cell carcinoma. Although primary carcinoma developed in vesical diverticulum was initially reported by Williams in 1883, adenocarcinoma is very rare. The diagnosis is often challenging and the prognosis is dire. Both our cases were successfully treated with total cystectomy and an ileal neobladder was constructed for total bladder replacement. Careful management and aggressive therapy for such patients may make even cure possible.

Adenocarcinoma↗

PubMed1999

Cyclopentenosine, major trifunctional crosslinking amino acid isolated from acid hydrolysate of elastin.

A trifunctional crosslinking amino acid named cyclopentenosine (CP) was isolated from the hydrolysate of bovine nuchal ligament elastin. CP and its derivatives were identified by spectroscopic methods. CP was found to consist of a 2-cyclopenten-1-one structure and its imine-enamine tautomers with enantiomers in H(2)O. A model reaction for the formation of the CP crosslink using model compounds for allysine (propanal) and lysine (n-butylamine) demonstrated that CP is composed of 2-cyclopenten-1-one and alpha, beta, gamma, delta-unsaturated aldehyde derived from three allysine residues. An ion-paired high-performance liquid chromatographic method for the determination of CP was developed. Among various bovine tissues the nuchal ligament had the highest concentration of CP. The age-related changes in the concentration of CP were examined in the aorta from rat (short-lived species) and bovine (long-lived species). The CP content was very low in the newborn rat but increased markedly with growth. After maturity, the CP content remained nearly the same or slightly decreased. In bovine aorta, the CP content scarcely changed from 7 months to 16 years.

Aging↗

PubMed1999

Lysyl oxidase coupled with catalase in egg shell membrane.

The activity of lysyl oxidase was found in egg shell membrane (ESM) of hens. The activity was determined by measuring the enzymatic conversion of n-butylamine and Nalpha-acetyl-L-lysine to n-butyraldehyde and Nalpha-acetyl-L-allysine, respectively. ESM lysyl oxidase was significantly inhibited by beta-aminopropionitrile, chelating agents, and deoxygenation, consistent with the known properties of lysyl oxidase. Nevertheless, ESM lysyl oxidase was insoluble in urea solution, suggesting that it complexes with ESM. These findings support previous reports indicating the presence of lysine-derived cross-links in ESM and the necessity of lysyl oxidase located in the isthmus of the hen oviduct for the biosynthesis of ESM. Lysyl oxidase secreted around the egg white from the isthmus may initiate the cross-linking reaction of ESM protein, and remain as the constituent of ESM. Moreover, the H(2)O(2) released by lysyl oxidase in ESM was completely decomposed by coexisting catalase activity. ESM lysyl oxidase activity was greatly elevated in the presence of H(2)O(2), probably due to the O(2) produced by catalase. These findings indicate that lysyl oxidase is coupled with catalase in ESM. This coupling enzyme system was considered to be involved in the biosynthesis of ESM and to protect the embryo against H(2)O(2).

Animals↗

PubMed1999

Observations of prostate specific antigen doubling time in Japanese patients with nonmetastatic prostate carcinoma.

BACKGROUND: To understand better the natural history and biology of prostate carcinoma occurring in Japanese patients, the authors attempted to define changes with time in prostate specific antigen (PSA) measurements in 48 men with clinically resectable T1-T3 nonmetastatic disease. METHODS: The authors analyzed PSA changes prospectively in prostate carcinoma patients who were managed by watchful waiting. PSA doubling time was calculated by linear regression. These values and their distribution were compared with clinical parameters and with published series of prostate carcinoma patients. RESULTS: The mean age of the 48 patients at the time of diagnosis was 74.2 years. The median follow-up from the time of diagnosis was 24.0 months. The median PSA doubling time was 35.7 months. In 27.1% of patients, there was no increase in the PSA level over the observation period. A rapid rise in PSA (doubling time of <2 years) was observed in 29.2% of patients. These results in Japanese patients are virtually the same as those reported in Western countries. There was no statistically significant relation between calculated PSA doubling time and clinical disease stage, tumor grade, PSA level at the time of diagnosis, probability of extraprostatic disease, patient age at diagnosis, or prostate volume (P > 0.05). CONCLUSIONS: Prostate carcinoma may not differ significantly by race once it becomes clinically manifest. The magnitude of positive changes in PSA over a given period of observation may not be helpful in determining the need for therapy. The previously reported incidence of clinically insignificant prostate carcinoma, which primarily was based on pathologic findings in surgical specimens, may have been an underestimation.

Aged↗

PubMed1999

Mutagenic activity of 2-phenylbenzotriazole derivatives related to a mutagen, PBTA-1, in river water.

A mutagen, 2-[2-(acetylamino)-4-[bis(2-methoxyethyl)amino]-5-methoxyphenyl]5-ami no-7-bromo-4-chloro-2H-benzotriiazole (PBTA-1), isolated from water of the Nishitakase River in Kyoto exhibits potent mutagenic activity in Salmonella typhimurium TA98 with S9 mix and has characteristic moieties, including bromo, chloro, acetylamino, bis(2-methoxyethyl)amino and primary amino groups on a 2-phenylbenzotriazole skeleton. The mutagenicities of PBTA-1, its congeners and five related 2-phenylbenzotriazoles were examined in S. typhimurium TA98 with S9 mix in order to elucidate the structure-activity relationships. The data obtained suggest that a primary amino group plays an essential role in the mutagenic activity as do aromatic amines including heterocyclic amines in cooked foods. The effect of planarity of the 2-phenylbenzotriazole ring was significant, and in addition, halogen groups of PBTA-1 influenced the enhancement of the mutagenic activity.

Animals↗

PubMed1999

Use of RhD fusion protein expressed on K562 cell surface in the study of molecular basis for D antigenic epitopes.

The human D antigens, one of the most clinically important blood groups, are presented by RhD protein with a putative 12 transmembrane topology. To understand the molecular basis for the complex antigenic profile of RhD protein, we expressed a series of RhD fusion proteins using different portions of Duffy protein as a tag in erythroleukemic K562 cells. Because the reactivity of monoclonal anti-RhD antibody, LOR15C9, depends mainly on the sequence coded by exon 7 of RhD, we altered DNA sequence corresponding to the amino acid residues 323-331(A) and 350-354(B) in the exon 7. The mutation in region B resulted in a severe reduction in LOR15C9 binding by flow cytometry analysis, suggesting that region B may play an important role in constituting antigen epitopes recognized by LOR15C9. On the other hand, a slight decrease in the antibody binding was observed for the region A mutant, suggesting that the intracellularly located region A may elicit a long distance effect on the formation of exofacial antigen epitopes. In addition, using various monoclonal antibodies against RhD, we compared the antigenic profile of expressed RhD fusion protein with that of endogenous RhD in K562 cells as well as in erythrocytes.

Amino Acid Sequence↗

PubMed1999

Exercise-induced ST elevation in patients with arrhythmogenic right ventricular dysplasia.

To test the hypothesis that local or diffuse wall motion abnormalities in the right ventricle in patients with arrhythmogenic right ventricular dysplasia (ARVD) may induce the ST-segment elevation in response to exercise, we examined exercise electrocardiograms in patients with ARVD. In 17 patients with ARVD, who demonstrated right ventricular wall motion abnormalities without organic coronary lesions, we conducted a treadmill exercise test. Significant exercise-induced ST-segment elevation (ESTE) was defined as a 0.1 mV or more ST-segment elevation at J point. ESTE was observed in 11 patients (65%). It manifested most frequently in right-sided precordial leads. Severe right ventricular asynergy was seen in all but one (91%) among 11 with ESTE, whereas it was seen only in two (33%) among six without ESTE (P<.05). The maximal magnitude of ESTE inversely correlated with right ventricular ejection fraction (r = -0.58, P<.05). ESTE was seen in two thirds of ARVD patients, helping us noninvasively diagnose ARVD. The fact that ventricular wall motion abnormalities could cause ESTE in the absence of organic coronary lesions suggested the critical role of mechanical factors in the genesis of ESTE.

Adolescent↗

PubMed1999

Limited suppression of prostate-specific antigen after salvage radiotherapy for its isolated elevation after radical prostatectomy.

OBJECTIVES: To investigate the clinical outcome and degree of prostate-specific antigen (PSA) suppression after salvage radiotherapy performed because of isolated PSA elevation after radical prostatectomy. METHODS: We examined the outcomes of 32 patients who underwent radiotherapy after radical prostatectomy. Hypersensitive, as well as conventional, PSA assays were used to measure PSA levels after irradiation. RESULTS: Of 125 patients who underwent radical prostatectomy for clinically resectable prostate cancer, 42 (33.6%) developed detectable PSA an average of 13.5 months postoperatively. Thirty-two patients underwent salvage radiotherapy. In 13 patients (40.6%), PSA became undetectable (less than 0.1 ng/mL) at a mean of 1.2 months. Two of these patients later developed detectable PSA within 1 2 months. Of 22 patients who had at least 12 months of follow-up, 8 had a durable PSA response. Of 13 patients who attained an undetectable PSA postoperatively and then showed a delayed progressive increase, 7 exhibited a durable response lasting for more than the 12 months after irradiation. By contrast, only 1 of 9 patients with persistently elevated postoperative PSA showed undetectable levels after irradiation. Frozen sera from the 8 patients with a durable response to irradiation were available to measure levels less than 0.1 ng/mL by hypersensitive assay. The mean value was 0.035 ng/mL at an average of 26.9 months after irradiation. Only 3 patients had levels less than 0.01 ng/mL. CONCLUSIONS: Although radiotherapy may be beneficial in a small number of patients, many patients continue to have measurable levels of PSA (more than 0.01 ng/mL) after irradiation. Our results suggest that this treatment in its current form is inadequate to eradicate residual carcinoma.

Aged↗