Binding of Alz 50 depends on Phe8 in tau synthetic peptides and varies between native and denatured tau proteins.

Alz 50 is a monoclonal antibody that in Western blotting analysis recognizes both normal tau as well as hyperphosphorylated tau proteins associated with paired helical filaments (PHF-tau) in Alzheimer disease (AD). Within tissue sections of AD brain, however, Alz 50 immunolabels only PHF, which suggests that the antibody recognizes a conformational epitope. Using competitive enzyme-linked immunosorbent assay, we demonstrate that Alz 50 binds to tau synthetic peptides with low affinity (KD between 0.27 to 2.7 x 10(-5) M) and that the binding is specific for the RQEF sequence corresponding to N-terminal residues 5-8 of tau. The Alz 50 epitope appears to be largely dependent on Phe8, a strongly hydrophobic amino acid residue, since the substitution of Phe8 with Ala8 in the synthetic peptide abolishes Alz 50 binding. The effects of tau conformation on Alz 50 binding were studied with various normal tau proteins with either low or high phosphate content (adult vs. fetal) and PHF-tau proteins. The normal tau fractions were isolated from both adult and fetal human brains using affinity chromatography (native form) and heat/perchloric acid treatments (denatured form). PHF-tau was isolated as Sarcosyl-insoluble fraction. With competitive ELISA, the denatured form of normal tau (fetal and adult) bound Alz 50 with the same high affinity as did PHF-tau (KD between 1.3 to 1.8 x 10(-7) M). In contrast, the native form of tau from either brain was unable to fully compete for Alz 50 and at most only 50% of the Alz 50 binding sites in native tau were occupied. These results suggest that native tau may exist either in complexes with other proteins or in a form of dimers/oligomers, in which only some N-termini are available for binding (e.g. head-to-tail assembly). The results also suggest that denaturation rather than phosphorylation of tau has more significant effect on interactions of tau with Alz 50.

Treatment of localized prostate cancer with intermittent triple androgen blockade: preliminary results in 110 consecutive patients.

OBJECTIVES: To determine the effectiveness of triple androgen blockade as an alternative to watchful waiting, radical prostatectomy or radiation therapy in the management of patients with clinical stage T1 to T3 prostate cancer. METHODS: The records of 110 consecutive patients were retrospectively evaluated. Patients were treated with a three-drug androgen blockade regimen, consisting of a luteinizing hormone-releasing hormone agonist (leuprolide or goserelin) plus an antiandrogen (flutamide or bicalutamide) plus finasteride (a 5-alpha-reductase inhibitor), followed by finasteride maintenance therapy, as the sole intervention. All patients refused local therapy and had their prostates intact. Determinants of efficacy included serum prostate-specific antigen (PSA) levels and disease-specific survival. RESULTS: Patients were treated for a median of 13 months with triple androgen blockade. At baseline, mean PSA level was 13.2 +/- 1.2 ng/ml (range, 0.39-100 ng/ml), and mean Gleason score was 6.6 +/- 0.1 (range, 4-10). During treatment, PSA levels declined to < or =0.1 ng/ml in all patients, with a median time of 3 months. After a median follow-up of 36 months since initiation of treatment, PSA levels have remained stable in 105 of 110 patients (95.5%). At a median follow-up of 55 months (range, 38-125 months), the mean PSA level for the first 57 patients treated in this series is 1.88 +/- 0.1 (range, 0-11.0 ng/ml). Only 9 of 110 (8.1%) patients have a PSA level > or =4.0 ng/ml. To date, no patient has received a second cycle of hormone blockade. CONCLUSIONS: Although median follow-up is short, triple androgen blockade therapy followed by finasteride maintenance appears to be a promising alternative for the management of patients with clinically localized or locally advanced prostate cancer. Further study of this approach is warranted.

Breast self-examination among diagnosed breast cancer patients.

The practice of breast self-examination (BSE) was explored by personal interview in a sample of women with diagnosed breast cancer. Despite physician recommendations to practice BSE, only 43% of those interviewed were examining themselves regularly, a figure that is little different from that of the general population. Predictors of BSE were age (older women were less likely to practice) and practice of BSE before diagnosis. Factors contributing to nonpractice were judged to be: (1) the patients' beliefs that occasional examinations by physicians are a sufficient substitute for BSE; (2) the patients' perceptions that BSE is discretionary and not truly "medical"; and (3) the fact that BSE may raise patients' anxiety over cancer without affecting its likelihood. It was concluded that the practice of BSE among diagnosed patients could be increased if physicians stress its importance and provide systematic instruction or reinstruction in its practice.

Illness-related and treatment-related factors in psychological adjustment to breast cancer.

Seventy-eight breast cancer outpatients were interviewed and their medical records were reviewed to document illness-related and treatment-related factors associated with psychosocial adjustment. Poor prognosis and more radical surgery both independently predicted poor psychological adjustment. The effect of type of surgery appeared to be mediated by the patient's sense of disfigurement and by changes in the sexual and affectional patterns in the marriage, rather than by prognosis or disability. Degree of dysfunction and whether or not the patient had radiation therapy or chemotherapy had no independent effects on psychological adjustment. Results point to the problematic psychosocial outcomes associated with mastectomy and, more generally, to the illness- and treatment-related factors that may place a breast cancer patient at risk for psychosocial adjustment problems.